4-30-19 Newly recognised form of dementia could now be easier to diagnose
Researchers have published guidelines for diagnosing a newly recognised form of dementia that progresses more slowly than Alzheimer’s disease and tends to affect people near the end of their lives. Unlike people who have Alzheimer’s disease, people with limbic-predominant age-related TDP-43 encephalopathy (LATE) don’t accumulate beta-amyloid or tau proteins in their brains. But previous studies have implicated a misshapen form of a different protein, called TDP-43, in the condition. In its healthy form, TDP-43 helps regulate gene activity in the brain, and misfolded TDP-43 is also thought to play a role in motor neurone disease, a rare condition. However, misfolded TDP-43 is very common in older adults, and the team behind the new guidelines say that roughly a quarter of people over the age of 85 have enough abnormal TDP-43 to affect their memory and thinking ability. “Now that the scientific community is on the same page about LATE, further research into the ‘how’ and ‘why’ can help us develop disease-specific drugs that target the right patients,” says Peter Nelson, of the University of Kentucky, who co-chaired the international group that drew up the guidance. It is possible to have both Alzheimer’s and LATE, in which case people tend to experience a more rapid decline in mental function.
4-30-19 A mysterious dementia that mimics Alzheimer’s gets named LATE
It’s possible about a quarter of people age 85 and older have the newly described disease. A newly described dementia strikes people in their last decades of life. The disease, aptly named LATE, comes with symptoms that resemble Alzheimer’s disease, but is thought to be caused by something completely different. An international team of scientists and clinicians describe the disease and officially christen it LATE, which stands for the more technical description, “limbic-predominant age-related TDP-43 encephalopathy,” online April 30 in Brain. Study coauthor Peter Nelson, a neuropathologist at the University of Kentucky in Lexington, helped organize a meeting last year that addressed a growing realization among doctors and scientists: “There’s this disease, and it doesn’t have a name,” he says. Estimates vary, but it’s possible that about a quarter of people age 85 and older have LATE, Nelson says. “This is a disease that really attacks the very latest portion of the human aging spectrum,” he says. LATE comes with memory trouble and dementia — symptoms that mirror Alzheimer’s, Nelson says. But instead of the plaques and tangles that mark the brains of people with Alzheimer’s disease, LATE is characterized by a lesser-known protein called TDP-43. In LATE, that protein accumulates and spreads through parts of the brain that are key to thinking and memory, including the amygdala and hippocampus. In Brain, Nelson and his colleagues describe the signs of LATE in the brain in a series of stages, from less severe to most severe. But the trouble is that these signs, which include the spread of TDP-43 and occasionally signs of damage to the hippocampus, can be found only after a person has died.
4-30-19 Sales of opioid painkiller codeine have halved in Australia
Sales of codeine have halved in Australia since it became a prescription-only drug, and fears that the change would drive people toward stronger opioids appear to be unfounded. The decision to ban over-the-counter sales of the opiate painkiller came amid a growing concern about the opioid epidemic sweeping through the US. Similar problems were emerging in Australia as codeine-related deaths had more than doubled in the decade to 2009. Before February 2018, Australians could buy low-dose codeine in combination with other painkillers such as paracetamol and ibuprofen without a prescription. But codeine, like other opioids, can lead to dependence and tolerance. Consuming large amounts of codeine in these formulations also puts people at risk of harms from the other ingredients, including liver and gastrointestinal damage, blood potassium imbalances and heart attack. While the ban was popular among doctor groups, critics warned it would put pressure on addiction services and lead to an uptick in demand for high-strength opioids. Now an analysis of codeine sales by Australia’s Therapeutic Goods Administration has found that Australians only bought half as many packets of codeine-containing products once they became prescription-only, from an average of 35 million per year between 2014 and 2017, down to 17 million in 2018. This is equivalent to 7000 kilograms of codeine less than would have been expected without the ban. Nevertheless, sales of the higher strength, 30 milligram packets remained similar. “Our analysis does not support the assertion that many patients were switched from low- to high-strength codeine medicines after up-scheduling,” the Therapeutic Goods Administration said in a statement.
4-30-19 Weird chromosome may have spurred evolution of thousands of songbirds
There’s more to songbird sex than we thought. It seems that all of them have an extra chromosome in their sex cells that isn’t seen elsewhere in their bodies. The extra DNA could help explain why songbirds account for roughly 5000 of the 10,000 known bird species. Songbirds typically have 40 pairs of chromosomes in most cells of their body. But in the late 1990s, biologists studying zebra finches made an odd discovery. Some of the cells involved in sexual reproduction, called germline cells, carried an additional pair of chromosomes. At the time zebra finches were considered a genetic oddity, says Pavel Borodin at Russia’s Institute of Cytology and Genetics in Siberia, and few researchers bothered to investigate any further. But now Borodin and his colleagues have discovered other songbirds have a 41st chromosome pair too. They examined the chromosomes of 14 species scattered across the family tree of songbirds, including finches, skylarks and canaries, along with chromosomes from eight non-songbird species. All 14 songbirds carried the extra chromosome in their germline cells, but none of the non-song birds did. Borodin says this suggests the extra chromosome may have first appeared in the last common ancestor of all songbirds, which lived about 35 million years ago and as such is probably present in all modern songbirds. Borodin thinks the 41st chromosome may help during sexual reproduction by providing more protein and nutrients for developing sperm and egg cells. Two studies published last year that looked at the zebra finch’s extra chromosome in more detail back up the idea. They found evidence that it contains additional copies of protein-generating genes found elsewhere in the genome.
4-29-19 How holes in herd immunity led to a 25-year-high in U.S. measles cases
Too many unvaccinated people are helping the virus spread. Measles is so contagious that the virus can unerringly find the unvaccinated. That knack, combined with the number of people in the United States who haven’t been vaccinated against the disease, has given measles an opening that it hasn’t had in the country for decades. U.S. measles cases have surged to a 25-year high of 704, the U.S. Centers for Disease Control and Prevention reported April 29. The record-breaking number of cases largely stems from an outbreak in Washington, which officials now say is over, and ongoing outbreaks in New York City and New York state. The vast majority of the cases, 88 percent, originated in close-knit communities that have low rates of vaccination, according to the CDC. And 503 of the 704 cases were in those who have not been vaccinated. The virus is eliminated in the United States, which means that it is no longer endemic, but travelers can still bring it into the country. “When measles is imported into a community with a highly vaccinated population, outbreaks either don’t happen or are small,” Nancy Messonnier, the director of CDC’s National Center for Immunization and Respiratory Diseases, said in a news briefing. But once introduced into a community with low vaccine coverage, “it is difficult to control the spread of disease,” she said. Cases are reported in 22 states, with new outbreaks (defined as at least three cases) in Maryland, Georgia and Los Angeles County. The six infected people in that county included students who potentially exposed the campuses of UCLA and California State University, Los Angeles to measles. To contain the outbreak, health officials told hundreds of students and staff to stay home until they could prove that they’d been vaccinated.
4-29-19 A science-themed escape room gives the brain a workout
A quantum physicist discusses what he learned from starting LabEscape. Professor Schrödenberg is missing, and evil agents want to use her quantum computing research for nefarious purposes. Stopping them is up to you, but completing your mission will require solving some mind-bending puzzles —based on science. If you are up for the challenge, you can test your wits at LabEscape, a science-themed escape room at the Lincoln Square Mall in Urbana, Ill. Escape rooms are a popular group activity, in which a team of players is enclosed in a room and must solve puzzles to either escape the room or accomplish a goal within a certain amount of time. LabEscape, created by a bona fide physicist and a crew of physics students, requires no previous scientific knowledge to play. But it does take a willingness to think creatively and work together as a team. Science News had the opportunity to try out a different version of LabEscape in Boston at a meeting of the American Physical Society in March. In this case, the challenge was to decode the fictional Professor Schrödenberg’s password to submit her grant proposal. The tasks necessary to break the code had our small group, consisting of adults and children, scientists and science rookies, running from one side of the room to the other, fiddling with lasers, polarized glasses, thermal imaging cameras and more. Many puzzles required discovering the specific action necessary to reveal a cleverly hidden message — often eliciting excited gasps from our group. Solving one puzzle led to others, until finally, we cracked the code and saved the day.
4-29-19 An Indian village has many more twins than can be explained
A small village in India is seeing an explosion in the number of twins born – and no one knows why. Kodinhi, in the southern state of Kerala, now has one thousand twins in a population of eleven thousand and the twin birth rate is still increasing. “It’s out of this world,” says Lorena Madrigal of the University of South Florida. The background rate of twin births in India is about one in a hundred, so the twin numbers in Kodinhi stand out. The phenomenon came to global attention in 2009, but the explanation is a mystery. So Madrigal’s team went to the village to see if they could find any clues about possible genetic or environmental causes. They spoke to households that included nearly half the twins in the village, and drew up family trees comprising about 1800 people going back to the 1860s. Though they didn’t manage to pinpoint why the trend was happening, they did manage to rule out a few suggested explanations. Firstly, marriage within families does not to appear to be the cause. As some genes raise the chance of having twins, it was thought the village’s tradition of marriage between first cousins and between uncles and nieces could be concentrating these genes in certain families. However, the team found twins were not more likely from such unions. The recent start and steep rise in twin births also points against cousin marriage being the trigger, says Madrigal. “They have always practised it.” Another possible explanation suggested in previous media reports was a past disease epidemic. People with genes that favoured twins could have been more likely to survive the disease for some reason.
4-29-19 How aphids sacrifice themselves to fix their homes with fatty goo
When a predator bites a hole in a colony’s home, soldiers gush white gluey stuff for a patch. However badly that home renovation goes, be glad you’re not a young aphid. Colonies of tiny Nipponaphis monzeni aphids in eastern Asia use their own young as part repair crew, part repair goo. The tiny fluffs of juvenile insects end up dying after gushing white glop from their bodies to repair a hole in the wall protecting their colony in Asian winter hazel trees. New details of this patching chemistry suggest that these doomed young aphids are a colony’s version of immune system cells, researchers report April 15 in the Proceedings of the National Academy of Sciences. The need for repair can arise while hundreds or thousands of these aphids live inside a hard-shelled, closed lump called a gall, which forms on the trees and balloons around the insects over several years. When a caterpillar manages to chew through the wall, white wingless aphid youngsters called soldiers, swollen almost to bursting with fluids, rush to the breach. Some soldiers mob and sting the intruder. Others get on with patching the hole. They “erupt,” says evolutionary biologist and entomologist Takema Fukatsu of the National Institute of Advanced Industrial Science and Technology in Tsukuba, Japan. From paired openings, or cornicles, near the rear, each soldier pops out huge (in aphid terms) white gobs of fatty substances and other compounds that plaster the hole. Some aphids get fatally stuck in the hardening patch, and some perish marooned outside the gall. As for the rest, releasing so much fluid shrivels the half-millimeter-long youngsters down to about a third of their body size. That means “the soldiers must die sooner or later,” Fukatsu says.
4-28-19 Why hasn't evolution cured aging?
With all the remarkable things evolution has done, you'd think it would have solved this problem by now. Life pits the order and intricacy of biology against the ceaseless chaos of physics. The second law of thermodynamics, or the thermodynamic arrow of time, states that any natural system will always tend towards increasing disorder. Biological aging is no different, making death inevitable. However, one of the least-addressed questions of aging is the apparent paradox between the optimizing drive of evolution, and the inevitable deterioration of the body. Considering the 3.5 billion years in which we have evolved from single-cell organisms, why hasn't life countered the inefficiency of aging? Or more accurately, how has aging persisted within the Darwinian framework of evolution? For evolution to occur, there must first be genetic variation, a difference between individuals within a population for a measurable characteristic (phenotype) arising from genetic and environmental factors; inheritance of these genetic factors from parents to their offspring; and differential reproductive success, such that certain genetic factors manifest themselves in an individual's capability to survive and reproduce (i.e., fitness). Consider aging in this evolutionary framework. There is an obvious variation in lifespan across different individuals throughout the world, impacted by genetic factors, but also influenced strongly by external factors such as the country's gross domestic product. Lifespan is also an inherited trait, with approximately 23 to 26 percent of the variation in lifespan between individuals caused by genetic factors, otherwise known as heritability. Moreover, it makes sense that an increased lifespan, or improved health over your life leading to an increased lifespan, would render you more attractive to the other sex, and increase your likelihood of reproductive success. So if these three evolutionary criteria have been met for the trait of longevity, why don't we live for an unheralded number of years? (Webmaster's comment: Nature cares only that you reproduce and raise the kids. After you've done that get out of the way.)
4-28-19 Why war’s emotional wounds run deeper for some kids and not others
‘Environmental sensitivity’ raises PTSD risk for Syrian refugee kids. After her husband’s death in Syria’s civil war, Amouna Sharekh Housh gathered her eight children and headed for safety in the neighboring country of Lebanon. At the Lebanese border, Islamic State (ISIS) militants demanded that Housh hand her children over to them. She refused, even when an ISIS soldier put a gun against the head of her then 9-year-old son, Manar. After passing through that hellish checkpoint, the still-intact family moved into a Lebanese refugee camp. Their house was a tent. Food was scarce, and sanitation was absent. A year later, the entire family was struggling. Once-calm children were now jittery and emotionally volatile. Manar’s condition had taken a particularly bad turn. He suffered from post-traumatic stress disorder (PTSD), a condition that includes having tormenting thoughts and dreams about distressing events, feeling detached from others, staying in a constant state of high-alert for potential dangers and reacting violently to minor frustrations. Housh shared her family’s trials with workers at a Beirut therapy and vocational training center run by the New York City–based nonprofit Art of Hope, and gave them permission to tell her story on the organization’s website. Housh’s family represents one drop in a sea of tears pouring out of Syria. Since civil war erupted in early 2011, the U.N. High Commission on Refugees (UNHCR) estimates that more than 5 million Syrians have fled the country; another 6.6 million people displaced from their homes are still living in Syria. UNHCR has registered about 1 million Syrian refugees in Lebanon, more than half of whom are 17 or younger — though the Lebanese government pegs the total number of Syrian refugees there at more than 1.5 million.
4-26-19 Health care: An allergic reaction to Medicare for All
“Health-care stocks have a Washington, D.C., problem that is likely to linger,” said Charley Grant in The Wall Street Journal. Companies across the health-services industry, from insurance giant UnitedHealth Group to Johnson & Johnson and pharma firm Abbott Laboratories, have been getting hammered in the stock market in recent weeks even though they’ve posted strong earnings. The reason is that investors are panicking about a future threat to those earnings: Medicare for All. Pushed by Sen. Bernie Sanders and other leading contenders for the Democratic Party’s presidential nomination, the policy would broaden government-run insurance to cover all Americans. It might be a death sentence for private health insurance companies, and—by giving the government the power to negotiate more favorable terms with providers—would likely slash profits “for hospitals and manufacturers of drugs and devices.” The sell-off is “reviving memories of the 2008 financial crisis,” said Cristin Flanagan and Tatiana Darie in Bloomberg.com. Insurance and hospital stocks lost $28 billion in market value in one day last week. While this kind of volatility is not unprecedented ahead of a presidential election, a full recovery could “hinge on whether it appears a single-payer policy would truly ban private health insurance policies.” Health-care stakeholders are taking no chances, said Dan Diamond in Politico.com, and some are going on the offensive. The Massachusetts Health & Hospital Association, which represents some of the state’s largest health-care facilities, has come out against Medicare for All, saying it would “inhibit access and harm health-care quality across the country.” Yet shaking up our health-care system still has “potent political appeal, and not just for those on the Left,” said Max Nisen in Bloomberg.com. Sanders received cheers when he brought up the idea at a Fox News town hall last week. UnitedHealth CEO David Wichmann has tried to push back, saying radical reform isn’t needed because “health care’s relative burden on society has lessened” over the past 16 months. But Americans are painfully aware that they spend more than any other country on health care and get worse results. If the “stock slide says anything, it’s that health-care companies need to sharpen their arguments.” (Webmaster's comment: And at least as low cost and effective as Europeon healthcare.)
4-26-19 Measles: Can parents be forced to vaccinate?
Measles “has made a comeback,” said Madeline Marshall in Vox.com, and its return has sparked a government crackdown on parents who don’t vaccinate their kids. The completely preventable viral disease was declared eradicated in 2000, but in the first few months of 2019, officials have reported 626 cases nationwide—more than in all of 2018. The highly contagious virus can cause fatal complications such as pneumonia and encephalitis, particularly among young children, adults with compromised immune systems, and the elderly. The outbreaks have been mostly confined to small, insular communities, including Russian-speaking immigrants in Washington state and Orthodox Jews in New York. Since creating “herd immunity” requires 95 percent of a population to vaccinate, the outbreaks have pitted the needs of society against the individual liberty of anti-vax parents. That fight is particularly intense in New York City, said Jennings Brown in Gizmodo.com. The city has logged 359 cases—almost all in Brooklyn’s Orthodox Jewish neighborhoods. Health officials have ordered compulsory vaccinations in four hard-hit ZIP codes under threat of $1,000 fines. Five mothers retaliated by suing the city, arguing that the emergency order violated their religious liberty. But Brooklyn Judge Lawrence Knipel dismissed their case in a strongly worded opinion. “A fireman,” he noted, “need not obtain the informed consent of the owner before extinguishing a house fire. Vaccination is known to extinguish the fire of contagion.” This is undoubtedly a “sensitive issue,” said Elad Hakim in TheFederalist.com. But it appears Knipel’s decision is founded on solid legal precedent. The U.S. Supreme Court took up the question of mandatory vaccinations in 1902 amid a smallpox outbreak in Massachusetts. The court ruled in favor of the state, stating, “There are manifold restraints to which each person is necessarily subject for the common good.” For Orthodox Jews, this isn’t truly a religious issue, said Julia Belluz in Vox.com. Indeed, even most Orthodox rabbis believe vaccinating is a moral duty. But “anti-vaccine propagandists” still peddling debunked claims about autism specifically targeted the Orthodox commuçnity, because its members “live outside the mainstream” and are suspicious of modernity and technology. City officials now hope that educating them about the safety of vaccinations—combined with some legal coercion—will change their minds.
4-26-19 Measles outbreak: Trump tells Americans to 'get their shots'
President Trump has told Americans to "get their shots" as measles cases spread across the country. "The vaccinations are so important," he told reporters outside the White House. Nearly 700 cases have been reported across 22 states amid a resurgence of the highly infectious disease, the US Centers for Disease Control and Prevention (CDC) says. Mr Trump has previously appeared to link vaccines and autism. Public health experts say there is no link. Vaccination rates have dropped steadily in the US with many parents objecting for philosophical or religious reasons. Others, known as "anti-vaxxers", believe discredited information that vaccines cause autism in children. The CDC says measles cases have reached a level not seen since 2000, when the disease was eliminated from the US. Mr Trump's warning comes as hundreds of staff and students at universities in the Californian city of Los Angeles have been quarantined over fears they may have contracted measles. Those who were at risk of being infected were asked to stay at home unless they could prove their immunity. As of Thursday, 82 people at the University of California (UCLA) were unable to provide vaccination records, the university says. At California State University, 156 people - including library employees and students - could not provide records and remain in quarantine, AP news agency reported.
4-26-19 Senate to consider raising smoking age
Senate Majority Leader Mitch McConnell said he will introduce a bill later this month to raise the national smoking age from 18 to 21. The minimum age would also apply to purchasing vaping devices, which were used last year by 4.9 million middle school and high school students, according to a recently published Food and Drug Administration survey. Nearly nine out of 10 cigarette smokers try smoking by age 18, and in McConnell’s tobacco-producing state of Kentucky, 34 percent of cancers are tied directly to smoking. Twelve states and 450 localities have already raised the smoking and vaping age to 21. McConnell said he was primarily responding to an “unprecedented spike” in the number of teenagers who were vaping, or smoking e-cigarettes.
4-26-19 Kids swallowing batteries
The number of young children seen in emergency rooms after swallowing coins, batteries, toys, and other small objects has nearly doubled in two decades. Researchers from the Nationwide Children’s Hospital in Columbus, Ohio, found that more than 759,000 kids ages 6 and under were brought to ERs from 1995 to 2015 because they’d swallowed something. The average annual rate rose by 92 percent over that period: There were nearly 43,000 cases in 2015, up from about 22,000 in 1995. Most of the children were 1 to 3 years old, and 10 percent required hospitalization. The researchers believe the surge in cases is mainly due to the proliferation of electronic devices running on button batteries, reports ABCNews.com. Battery ingestions—the second-biggest cause for hospitalizations, after coins—increased 150-fold. Button batteries are particularly dangerous if swallowed, because they can trigger chemical reactions that cause potentially fatal internal burns. “What is of paramount importance is practicing safe storage,” says lead author Danielle Orsagh-Yentis. “If children can’t see them, they can’t be enticed by them.”
4-26-19 How space changes the body
A pioneering “twins study” by NASA has found that astronaut Scott Kelly experienced notable physiological changes during his year in space but no major long-term effects. Kelly lived on the International Space Station for 340 days in 2015 and 2016, while his identical twin brother, Mark Kelly, a former astronaut, served as a comparison subject back on Earth. Perhaps the most important finding was that Kelly’s telomeres—the protective structures at the end of chromosomes that usually shorten with age and stress—actually lengthened during his time in space. They reverted to average length when Kelly returned to Earth, before shortening even further. Kelly also experienced several changes in his gene expression—how genes turn on and off—particularly in relation to his immune system. The researchers said the findings contained nothing that would definitively rule out sending humans on a lengthy space voyage, such as a mission to Mars. But they emphasized that the study was limited, and that astronauts on the space station are protected from most harmful radiation. “We need to get [them] outside of low Earth orbit,” researcher Susan Bailey, from Colorado State University, tells The Washington Post. “Radiation exposure will certainly be a very big concern.”
4-26-19 Reviving ‘dead’ brains with artificial blood
In a landmark experiment that raises profound moral and philosophical questions about the line between life and death, scientists have partially restored cellular activity in the brains of slaughtered pigs. Researchers at Yale University acquired the brains of 32 pigs that had been killed at an abattoir, and four hours after they’d been without blood, pumped them with a chemical cocktail intended to slow or reverse the death of brain cells. The brains did not regain anything resembling consciousness—the artificial blood was designed to block nerve signals—but certain brain cells did regain metabolic activity, even responding to drugs, reports The New York Times. When researchers examined slices of brain tissue, they spotted electrical activity in some neurons. The experiment upends the long-held assumption that the brain dies quickly and irreversibly without oxygen. “What we are showing is the process of cell death is a gradual, stepwise process,” says study leader Nenad Sestan, “and that some of those processes can be either postponed, preserved, or even reversed.” Sestan and his team acknowledge that the research raises ethical questions and might change the protocols for organ donation, which rely on a donor being judged “brain dead.” But the breakthrough could also lead to new treatments to restore function in the brains of patients who have suffered strokes and traumatic brain injuries or are living with diseases like Alzheimer’s.
4-26-19 Your new distant relative
Mankind has a new ancestor: an unusual species of human that researchers believe lived in the Philippines as recently as 50,000 years ago. Remains of Homo luzonensis were first discovered in a cave on the island of Luzon in 2007, reports NPR.org. The fossilized body parts—which include teeth, part of a femur, and hand and foot bones—suggest the diminutive hominins stood no more than 4 feet tall, and used their toes for climbing trees as well as walking. Homo luzonensis is the fourth extinct human found in recent years, after the discoveries of Homo floresiensis in Indonesia in 2003, the Denisovans in Siberia in 2010, and Homo naledi in South Africa in 2013. Taken together, these finds suggest that human evolution was more variable than previously thought, with different groups adapting to conditions all over the world. Moreover, several different species may have coexisted with early modern humans. The discoveries will “play havoc with any easy classification” of our ancestors, says the Smithsonian’s Rick Potts, who wasn’t involved in the study. “The evolution of Homo is getting weirder and weirder.”
4-26-19 Hundreds of thousands of viruses in oceans
The oceans contain almost 200,000 different viral populations, according to the latest count. Marine viruses were found from the surface down to 4,000m deep and from the North to the South Pole. Though most are harmless to humans, they can infect marine life, including whales and crustaceans. And scientists are only just starting to understand how these tiny organisms play a role in the life and chemistry of the seas. Researchers drew up a global map of marine viruses based on seawater samples from nearly 80 sites around the world. Their viral tally is almost 12-fold higher than previous estimates. They were surprised to find that the viruses fell into just five groups based on their location and depth. "When we examined the genes of the viruses in each of those communities, we found evidence of genetic adaptation to the different zones of the ocean," said researcher Ann Gregory of KU Leuven in Belgium. The second surprise was that the Arctic Ocean had lots of different types of viruses. It had been thought that hotspots for microbial diversity would be at the equator. The world's oceans are teeming with viruses, yet we are at the edge of our understanding on how they impact ocean health and function. Among previous discoveries are "giant" marine viruses, which can infect green algae. A litre of seawater typically contains billions of viruses - the vast majority of which remain unidentified. In the latest dataset, 90% of the populations could not be classified to a known group. Better knowledge of ocean viruses is important because of their influence on other marine microbes, including bacteria and fungi. Viruses have an impact on all other tiny marine organisms, such as plankton, which produce more than half of the oxygen we breathe and absorb carbon dioxide from the atmosphere. "Without microbes, the Earth, its oceans, and even our human bodies come to a halt," said Matthew Sullivan of the University of Ohio. "Our lab is helping researchers finally 'see' the hidden viruses that infect these microbes."
4-26-19 How did the ancient Egyptians catch and mummify millions of ibises?
They were mummified in their millions. Stacks and stacks of sacred ibises were interred roughly 2,500 years ago as prayer offerings. At one site alone there are 1.75 million ibis mummies – where did the Egyptians get all these birds? DNA locked inside some of the avian mummies has now been extracted and analysed. The findings suggest that the birds were not reared on large industrial-scale farms as described in ancient hieroglyphs, but rather captured from the wild before sacrifice and mummification. Sally Wasef at Griffith University in Australia and colleagues ground up powdered bone and tissue from 40 well-preserved ibises. They then extracted DNA from the mitochondria, the energy-generating component in cells, using molecules designed to bind to it. The team used mitochondrial DNA because even in ancient samples there’s a good chance that it has been preserved. There are around 1,000 copies of it in each cell, says Wasef. From 40 mummified ibises, the team managed to sequence 14 complete mitochondrial genomes. They compared these with mitochondrial DNA from 26 modern day wild ibises and found a similar pattern of diversity. Had generations of the birds been reared on large farms, one would expect their DNA to be less diverse, a result of breeding bottlenecks. Wasef and her colleagues say that this shows that the ibises used in mummification were not taken from small, inbred populations. “It’s an impressive bit of work,” says Martin Collinson, at the University of Aberdeen. However, as the team only examined a small number of ibises, another explanation could be that birds were farmed on a large scale but topped up with wild birds regularly, says Collinson. “There could be an inbetweeny answer,” he says.
4-25-19 Peanut allergy immunotherapy may actually do more harm than good
For people with peanut allergies, undergoing immunotherapy may actually increase their risk of having allergic or anaphylactic reactions. Immunotherapy is an experimental treatment for allergies that involves repeated exposure to the allergen in gradually increasing doses, aiming to desensitise the patient’s immune system. To get a better understanding of how safe and effective it is, Derek Chu of McMaster University, Canada, and colleagues compiled data from 12 trials involving 1041 patients in total, most of them children aged five to 12. Some of the trials compared immunotherapy with a placebo, while in others, the comparison group were simply told to avoid peanut exposure. Patients who received immunotherapy had a 22 per cent risk of anaphylaxis – a life-threatening allergic reaction – during the follow-up period, which lasted around a year in most studies. That’s around three times higher than the risk for patients who did not have the therapy. Despite this, many trials have reported that immunotherapy is successful because participants passed a test in the clinic in which they eat some peanut without having a reaction. Chu says these tests are not the most important outcome measure for patients. Even if patients don’t show a reaction in the clinic, they may not be fully protected, and can go on to have severe reactions. “Common situations patients face can break their protection, often in an unpredictable manner,” says Chu. “Maybe they’re sick that day or tired or have an empty stomach; even having a hot shower – that can break their protection.” Immunotherapy usually involves daily doses of allergen, often taken by the patient at home. If doses are missed, this can also result in a loss of protection and an allergic reaction to the next dose.
4-25-19 Is China losing the battle against an incurable pig virus?
Global pandemics that impact on food supplies are scary things. The latest threat comes from African swine fever, a highly contagious virus with no known cure, and a near zero survival rate for infected pigs. The good news is that the disease is not harmful to human health. The bad news is that it will probably hurt our wallets. The epicentre of the current crisis is China, the world's biggest producer and consumer of pork. It alone accounts for more than half of the world's pig population. China is struggling to contain the disease, which has spread to every part of the country since August last year. After months of claiming the situation was under control, Beijing is now warning that pork prices in China could rise by more than 70% in the second half of this year. This in turn would have a knock-on impact on China's economy, given that pork prices are an important contributor to its inflation levels. Official data released over the past week reinforce the seriousness of the situation. China's National Bureau of Statistics says the country's pig population has fallen by nearly 40 million to 375.3 million from a year earlier, because of the swine fever outbreak. However some analysts believe that China has been under-reporting the situation, partly due to local farmers withholding information about outbreaks. Looking ahead, the epidemic could decimate around 200 million pigs in China, according to a grim report by Rabobank. It forecasts that China's pork output will fall by 30% this year, creating implications for global commodity markets."To give you some context, the decline here in China is now almost as much as the total amount of pork produced in the EU as a whole," says Rabobank global strategist Justin Sherrard. He says that China cannot import enough pigs to make up the shortfall. "We don't believe there's enough animal protein available in the world to make up the difference.
4-25-19 A lack of circular RNAs may trigger lupus
Balancing levels of these molecules could help rein in an overactive immune system. A lack of certain mysterious genetic molecules may spin the immune system out of control and lead to lupus. People with lupus have lower than normal levels of circular RNAs, triggering an immune reaction meant to fight viruses, biochemist Lingling Chen of the Shanghai Institute of Biochemistry and Cell Biology and her colleagues discovered. Switching on the body’s virus-fighting mechanisms when no harmful viruses are around may lead the immune system to attack the body. The team found that raising levels of these RNAs, known as circRNAs, in cells taken from lupus patients restored normal activity of a protein involved in rousing one arm of the immune system. The research, reported April 25 in Cell, raises “an intriguing possibility that introduction of certain circRNAs can dampen autoimmunity associated with lupus, suggesting circular RNA as a therapeutic strategy,” says Howard Chang, a geneticist at Stanford University who was not involved in the work. The most common type of lupus, systemic lupus erythematosus, is an autoimmune disorder in which the immune system attacks the body’s own tissues and organs. Though the exact number of people with this form of lupus isn’t known, estimates range between 161,000 and 322,000 people in the United States.
4-25-19 A global survey finds that the Arctic Ocean is a hot spot for viruses
Knowing where viruses are illuminates where carbon may be sinking. Arctic waters turn out to be teeming with some of the world’s smallest entities — viruses. Water samples taken during a three-year expedition around the world’s oceans identified around 200,000 virus species, roughly 12 times the number found in a previous smaller survey. And 42 percent of those viruses were found exclusively in the Arctic, researchers report April 25 in Cell. The results come from the Tara Oceans global oceanographic research expedition. From 2009 to 2013, researchers dropped tanks off of an aluminum sailboat called Tara to collect 145 water samples from dozens of sites worldwide, at water depths from 0 to 4,000 meters. Scientists collected everything ranging in size from fish eggs down to viruses. Filtering isolated the viruses, which were then genetically compared. The researchers identified 195,728 virus species parsed into five global regions that are home to distinct viral communities. The most diversity was found in shallow, temperate and tropical waters, followed closely by Arctic waters. Almost all of the viruses were bacteriophages, which attack bacteria — not people. “So you can swim in the ocean and not worry about it,” says Ahmed Zayed, a microbiologist at Ohio State University in Columbus. Bacteriophages and other viruses are credited with killing roughly 20 percent of bacteria in the ocean every day. That process stops carbon in the bacteria from passing up the food chain, and instead releases the carbon back into the ocean for other microorganisms — some of which also consume carbon dioxide. These microbes eventually produce a form of carbon that can’t be recycled and stays stored in the ocean.
4-25-19 Neanderthals may have prized golden eagle claws for symbolic value
Neanderthals seem to have placed special value on golden eagle talons, above those of other birds, based on a study of the frequency of different bird remains found in prehistoric human sites. This suggests the claws had a symbolic value, adding to the growing evidence that Neanderthals had more sophisticated lives than we thought, says Clive Finlayson at The Gibraltar National Museum, whose group did the analysis. When modern humans came to Europe forty thousand years ago, they overlapped with Neanderthals, our prehistoric cousins, for a few thousand years before Neanderthals went extinct. For a long time it was assumed we survived when they didn’t because we were smarter, but that has been challenged by recent finds of Neanderthal cave art and probable shell jewellery. Other finds include cut-marked bird talons and wing bones with feathers removed from many types of crows and birds of prey. Three talons from a white-tailed eagle were found in a Neanderthal site in Croatia, which have small matching notches suggesting they were strung on a necklace. Finlayson’s team noticed that cut-marked talons and bones were especially common from golden eagles, with nine such finds reported from Neanderthal caves. To see if this was just because golden eagles were more common at the time, they compared this figure with numbers of unmarked bones found in caves, for golden eagles, as well as other birds. For most bird species, the number of cut-marked remains correlated with the general prevalence of their bones. But golden eagle talons stood out as being more likely to show marks from human intervention – as if they were preferred.
4-25-19 21 million children miss first dose of measles vaccine every year
An estimated 169 million children worldwide have missed out on getting the first dose of a measles vaccine, according to an analysis by the children’s charity Unicef. This includes nearly 2.6 million children in the US, 608,000 children in France, and more than half a million children in the UK. The study analysed global data from 2010 to 2017, and found that an average of 21.2 million children are missing their first dose of vaccine every year. Children need two doses of the MMR vaccine for protection. An estimated 110,000 people – most of them children – are thought to have died from measles in 2017, a 22 per cent increase on the previous year. In the first three months of 2019, more than 110,000 measles cases were reported worldwide, up almost 300 per cent on the same period the year before. “The measles virus will always find unvaccinated children,” says Henrietta Fore, of Unicef. “If we are serious about averting the spread of this dangerous but preventable disease, we need to vaccinate every child, in rich and poor countries alike.” The World Health Organisation recommends that 95 per cent of people need to be vaccinated against measles to achieve herd immunity, which stops the infection spreading through populations. There is some good news – in 2016 and 2017, uptake of the first dose of the MMR vaccine in five-year-olds in the UK exceeded 95 per cent for the first time. However, uptake of the second dose of MMR in five-year-old children is 88 per cent. Unicef says low vaccination rates worldwide reflect “lack of access, poor health systems, complacency, and in some cases fear or scepticism about vaccines“.
4-24-19 U.S. measles cases hit a record high since the disease was eliminated in 2000
About 169 million kids worldwide didn’t get a measles shot in 2010–2017, easing disease spread. U.S. measles cases have soared to the highest number since the disease was declared eliminated in the country in 2000. The 2019 tally now stands at 695 cases, the U.S. Centers for Disease Control and Prevention reports. That surpasses the previous high of 667 cases in 2014. “The high number of cases in 2019 is primarily the result of a few large outbreaks — one in Washington State and two large outbreaks in New York that started in late 2018,” according to a statement released by the CDC April 24. “The outbreaks in New York City and New York State are among the largest and longest lasting since measles elimination in 2000. The longer these outbreaks continue, the greater the chance measles will again get a sustained foothold in the United States.” Years of inadequate childhood measles vaccination coverage throughout the world have set the stage for the resurgence in the United States as well as in many other countries. An estimated 169 million children globally were not vaccinated against measles from 2010 to 2017 — or an average of 21.1 million per year, according to data released April 24 by UNICEF to kick off World Immunization Week. “It is unfortunate where we stand in 2019 on measles control, given the fact that we have such an effective, safe and, very importantly, inexpensive vaccine available,” says Robin Nandy, Chief of Immunization at UNICEF in New York City. Among high-income countries, the United States tops the list of those with the largest numbers of kids who have not received the measles vaccine. UNICEF, the United Nations Children’s Fund, reports more than 2.5 million U.S. children went unvaccinated against the virus from 2010 to 2017. France has the next highest number, with more than 600,000 during those years, followed by the United Kingdom’s 527,000. The high U.S. and European numbers are explained mostly by parental resistance to vaccines (SN Online: 11/30/18).
4-24-19 Anti-ageing has often been seen as quack science. Not any more
HISTORY is littered with the corpses of people who claimed to have found the fountain of youth. So caution is warranted with claims of the imminent arrival of drugs to slow ageing. But the field of anti-ageing medicine is now a serious one. A decade ago you could go to conferences and hear outlandish predictions about people living to 150 years old or more, often accompanied by rolling eyes from many scientists in the room. Now the emphasis is no longer on radical life extension, but on ensuring we stay healthier for longer. If this translates into verified drugs, that could presage a medical, economic and social revolution. Keeping at bay the age-related conditions that are now the leading cause of mortality in the developed world will be a humanitarian triumph on a par with sanitation or vaccines. Of course there are possible downsides, for example if larger numbers of sprightly older people refuse to budge from jobs or homes coveted by younger folk. But such problems are fixable. Wouldn’t we rather that than a world in which the nursing home is the only way out?
4-24-19 The great wonder and strangeness of the human brain
A dazzling exhibition in Lisbon celebrates the most complex of human organs with art that makes the brain sing – as well as revealing how chimps can outsmart us. A FEW steps inside the Gulbenkian Foundation’s latest exhibition, a crowd of visitors halts, entranced. There is a faint collective “Wow” as they look up. In a twilight space, an enormous video screen shows a slice of human brain, but with its long, looping pathways and layers of nerve cells shimmering in gold. Colours change, the viewpoint slowly shifts and zooms, explores fine tangles of dendrites and the curves of axons before returning slowly to the big view. It takes a minute to see that this isn’t a real brain slice; it is a video of a hyper-real, microetched representation of the brain, computer-generated by neuroscientist Greg Dunn and physicist Brian Edwards. They call the work Self Reflected. In its idealised perfection we see what a wonder the brain is, and how astonishing it is that these soft loops and tangles are what creates the feeling of being “me”. The exhibition, Cérebro (Brain), is off to an extraordinary start. Its curator, Rui Oliveira, a neurobiologist at Portugal’s Gulbenkian Science Institute, tells me that he wanted to bring arts and science together to create an “emotional, sensorial and intimate environment that would make people feel amazed and instantly engaged”. He has succeeded, because what follows is an exhibition that continually renews our wonder at what science reveals. Laid out in elegant diagrams on pale grey surfaces in an intimately lit space, there is plenty to read on three big themes: the brain’s origins and complexity; the emergence of the mind; and the future of the brain in AI and robotics. But the wonder comes from the many exhibits that “enable people to experience their own brain in action”, as Oliveira puts it.
4-24-19 A neural implant can translate brain activity into sentences
Decoding the brain’s instructions to vocal tracts could someday help the speechless speak. To communicate, people unable to talk often rely on small eye movements to spell out words, a painstakingly slow process. Now, using signals picked up by a brain implant, scientists have pulled entire sentences from the brain. Some of these reconstructed words, spoken aloud by a virtual vocal cord, are a little garbled. But overall, the sentences are understandable, researchers from the University of California, San Francisco report in the April 25 Nature. Creating the audible synthetic sentences required years of analysis after brain signals were recorded, and the technique is not ready to be used outside of a lab. Still, the work shows “that just using the brain, it is possible to decode speech,” says UCSF speech scientist Gopala Anumanchipalli. The technology described in the new study holds promise for ultimately restoring people’s abilities to speak fluently, says Frank Guenther, a speech neuroscientist at Boston University. “It’s hard to overstate the importance of that to these people…. It’s incredibly isolating and practically nightmarish to not be able to communicate needs or socially connect. Existing speech aids that rely on spelling words are tedious, often producing about 10 words a minute. Earlier studies have used brain signals to decode smaller bits of speech, such as vowels or words, but with a more limited vocabulary than the current work.
4-24-19 'Exhilarating' implant turns thoughts to speech
Scientists have developed a brain implant that can read people's minds and turn their thoughts to speech. The team at the University of California, San Francisco says the technology is "exhilarating". They add that their findings, published in the journal Nature, could help people when disease robs them of their ability to talk. Experts said the findings were compelling and offered hope of restoring speech. The mind-reading technology works in two stages. First an electrode is implanted in the brain to pick up the electrical signals that manoeuvre the lips, tongue, voice box and jaw. Then powerful computing is used to simulate how the movements in the mouth and throat would form different sounds. This results in synthesised speech coming out of a "virtual vocal tract". You might think it would be easier to scour the brain for the pattern of electrical signals that code for each word. However, attempts to do so have only had limited success. Instead it was focusing on the shape of the mouth and the sounds it would produce that allowed the scientists to achieve a world first. Prof Edward Chang, one of the researchers, said: "For the first time, this study demonstrates that we can generate entire spoken sentences based on an individual's brain activity. "This is an exhilarating proof of principle that, with technology that is already within reach, we should be able to build a device that is clinically viable in patients with speech loss." (Webmaster's comment: It's pretty good, but not yet perfect.)
4-24-19 A marine parasite’s mitochondria lack DNA but still churn out energy
The missing genetic material turned up in the microbe’s nucleus. One parasite that feeds on algae is so voracious that it even stole its own mitochondria’s DNA. Mitochondria — the energy-generating parts of cells — of the parasitic plankton Amoebophyra ceratii seem to have transferred all of their DNA to the cell’s nucleus, researchers report April 24 in Science Advances. The discovery is the first time that scientists have found an oxygen-using organism with fully functional mitochondria that don’t have any mitochondrial DNA. (Some anaerobic organisms, which don’t need oxygen, and thus mitochondria, to survive, have also lost mitochondrial DNA.) Mitochondria are thought to be bacteria that were captured by other cells and eventually became standard parts of eukaryotic cells — cells that encase their DNA and other parts in membranes. Mitochondria reside outside of the nucleus in a cell’s jellylike guts, the cytoplasm. Part of the settling-in process involved relocating some genes needed for mitochondria’s function to the nucleus of host cells. But most mitochondria kept at least a few genes. (Human mitochondria held on to 37 genes.) Not so for A. ceratii, Uwe John of the Alfred Wegener Institute in Bremerhaven, Germany, and colleagues discovered. The parasite, which infects algae that can cause toxic blooms, has two mitochondria during the free-living stage of its life cycle. Both are able to produce energy, the researchers found. But the team couldn’t spot any DNA inside the mitochondria.
4-24-19 Over 400 languages spoken today may have originated in northern China
Although Chinese, Tibetan and Burmese languages sound completely different from one another, they are all derived from a common ancestral tongue. A new analysis suggests the ancient language might have emerged in northern China and spread to the south and west with agriculture. Mandarin, Cantonese, Tibetan and about 400 other languages all belong to a group called Sino-Tibetan languages because of their shared origin. The languages are spoken by over 20 per cent of the world’s population, only second to the Indo-European language group that includes English and Spanish. Menghan Zhang at Fudan University in Shanghai and his colleagues wanted to find out where the Sino-Tibetan languages originated. Because languages evolve and diverge just like biological species, the team applied statistical tools commonly used by biologists to build an evolutionary tree for Sino-Tibetan languages. The team compared how words that shared the same meaning are pronounced in different languages. Generally, two languages with many words sounding alike are more closely related than two languages with fewer similar words. The team produced an evolutionary tree for the languages and combined this with archaeological evidence of how people moved, such as the spreading of pottery and architecture styles, to conclude that the ancestral language to Sino-Tibetan languages arose in present-day northern China. Although it’s still unclear when the ancient language was first spoken, it split into two major branches about 6,000 years ago. One spread southwards, and the other spread to Tibet and south Asia. This timeline aligns with the spread of agriculture in ancient Asia, says Zhang.
4-24-19 Foragers may have settled in the Amazon 10,000 years ago
Evidence of human foragers have been found in the savannahs of the southwest Amazon that date back to between 4000 and 10,600 years ago. People are thought to have entered the area between 13,000 and 17,000 years ago, but these groups are thought to have moved around often. More settled foraging societies – which have more of an impact on the local land and animals – weren’t thought to have lived in the same region until about 2500 years ago. But José Capriles at Pennsylvania State University and his colleagues have found evidence to the contrary during their exploration of three Bolivian “forest islands” – circular patches of forest on the savannah that are like an oasis in the desert. As they dug down to 2 metres below the surface of the soil, they found burned earth, ceramic shards, seeds, charcoal remnants and the remains of five humans. The burials included both men and women. Their teeth were complete but heavily worn, which suggests that they were older adults who ate a diet high in shellfish, according to the team. Carbon dating of the soil layers suggests these people were buried between 6250 and 6820 years ago. Layers excavated beneath the burials included bones of deer, carnivores, armadillos, rodents and a few birds. Remains of fish and eels, which are common in archaeological sites in the area, were also found. The gastropod shells found throughout the sites suggest that these areas were near wetlands and the people inhabiting them collected and transported shellfish to be eaten in their settlements. In one of the forest islands, they found clumps of burnt clay that had hardened into ceramics in what may have been a kind of hearth, suggesting that these foragers had persistent or high-temperature fires.
4-24-19 Excavations show hunter-gatherers lived in the Amazon more than 10,000 years ago
Foragers may have laid the groundwork for farming’s ascent thousands of years later. Hunter-gatherers occupied the southwestern Amazon rainforest by around 10,600 years ago — at least several thousand years earlier than previously thought. Excavated food remains and human burials at several locations in Bolivia support a scenario in which hunter-gatherers regularly occupied those spots for large parts of the year. The unearthed evidence also indicates that the hunter-gatherers were living in the southwestern Amazon until around 4,000 years ago, anthropological archaeologist José Capriles of Penn State University and colleagues report online April 24 in Science Advances. If hunter-gatherers developed a preference for living in one place for months at a time, that may have led to the rise of farming societies in the southwestern Amazon around 2,500 years ago, the scientists speculate.Capriles’ team focused on three small, forested mounds of earth located in dry grasslands that flood during rainy months. The researchers uncovered deposits of burned clay and wood bits likely produced by fireplaces of some kind, snail shells and bones of fish and small mammals. Skeletons of five people buried at the three sites were also found. Radiocarbon dating places the ages of these graves at around 6,250 years old or more. As a drier climate took hold between roughly 8,000 and 5,500 years ago, hunter-gatherers in the southwestern Amazon may have intensified their occupations of campsites near patchy, seasonal wetlands for part of the year. By interring some of their dead at those sites, foraging communities may have claimed that valuable property and nearby wetland resources as theirs, the team suspects.
4-24-19 Anti-ageing drugs are coming that could keep you healthier for longer
Longevity research is no longer aimed at prolonging lives, it is trying to keep us fit right until the end. New anti-ageing drugs may finally be here to make that happen. MICHAEL WEST got talking to a guy next to him on an aeroplane. “The man asked what I did and I told him,” says West. The man seemed impressed and West continued, thinking he had a friendly audience. “But after a while he said: ‘You’re lying to me. I read everything and I’ve never heard any of this. This is so amazing and so revolutionary that if it was true, I would know about it already’.” The unbelievable story that West told his neighbour was about the science of ageing. An account of how biologists had finally figured out what causes us to grow old and die, and how biotechnologists like him – he founded biotech firm Geron in 1990 – were closing in on a cure. A cure for ageing. West realised his life’s work had an image problem. “Rejuvenation, age reversal – I completely believe it is possible,” he says. But “the gap between what scientists know and what even the educated public knows is huge.” Make no mistake: you are going to want to know about this. In a few weeks, an anti-ageing pill will be launched. In a few years, the first scientifically validated anti-ageing drugs could be on the market. Biotech companies are springing up to commercialise discoveries, and investors are betting serious money on what many predict will become the biggest industry of all time. As somebody who is approaching 50, I want to know about it too. The wrinkling, sagging and greying that are the outward manifestations of my inner decay are already upon me, and it is downhill from here. Before we go any further, let’s address the bugbear that haunts this field. History is filled with charlatans and hype-mongers who claimed ageing would be cured in their lifetimes or that immortality was within reach. This time it really is different. “In the past decade, we have made a major discovery,” says Richard Miller, a gerontologist at the University of Michigan. “We have proven that you can slow the ageing process using drugs. Ten years ago, people would have said, ‘That’s science fiction, there’s no reason to suspect that can ever be done’,” he says. “Those people have been proven wrong. It’s doable.” This isn’t just slowing ageing in worms, flies or even mice, it is in humans too. “It’s completely different to the old stuff, which was a bunch of cowboys, really awful,” agrees David Gems at University College London. Unlike many other biogerontologists, he has no commercial interests in anti-ageing medicines. “These are proper scientists working to normal standards. At the moment, it looks great.”
4-24-19 See beautiful fossils from top Cambrian sites around the world
You’ve heard of the Burgess Shale, but what about Sirius Passet? For most of the nearly 3.5 billion years of documented life on Earth, creatures were simple, dominated by organisms such as bacteria, algae and fungi (SN: 10/13/18, p. 10). Then, beginning about 541 million years ago, life quickly diversified into an array of new, complex forms. This flourishing, called the Cambrian explosion, took place within about 25 million years. Fossils from the period have been preserved in rocks at more than 50 known sites worldwide, the most famous of which is Canada’s Burgess Shale, discovered in 1909. At five standout Cambrian sites, hundreds to thousands of different species were buried in the soft mud of long-ago seafloors. Rapid burial led to the exceptional preservation of soft-bodied animals as well as of soft tissues, such as brains, guts, eyes and skin, that typically don’t fossilize well. A newly reported site, Qingjiang in China, holds a wealth of exquisitely preserved soft-bodied animals such as jellyfish and comb jellies. Here are some examples of the remarkable diversity of weird and wonderful Cambrian life found at these five sites:
- Marrella: Canada’s Burgess Shale (1909) 508 million years old
- Fuxianhuia: China’s Chengjiang (1984) 518 million years old
- Ctenophore: China’s Qingjiang (2007; reported 2019) 518 million years old
- Anomalocaris: Australia’s Emu Bay Shale (1979) 514 million years old
- Halkieria: Greenland’s Sirius Passet (1984) 515 million years old
4-23-19 Genetically modified virus may shrink incurable brain cancers
People with incurable melanomas and brain or breast cancers are to get injections of tumour-fighting viruses. The trial will test the safety of a virus that has been engineered to shrink tumours – an approach that holds promise for a range of cancers, including deadly brain tumours. The idea of using viruses to kill cancers goes back more than a century, inspired by anecdotal reports of some people with viral infections being cured of malignancies. But turning viruses that can infect and kill human cells into a safe and effective treatment that targets only tumour cells has proved tricky. Researchers are making progress at last. In 2015, the US Food and Drug Administration approved the first ever virus-based cancer treatment – a genetically modified herpes virus for advanced melanomas that can’t be completely removed by surgery. Many other virus-based treatments are in development. Amin Hajitou at Imperial College London and his colleagues have come up with an unusual form of viral treatment, based on a phage – a kind of virus that normally only attacks bacteria. In principle, it should be safer to use engineered phages in people than viruses that normally infect humans. The phages are designed to bind to cancer cells and inject DNA into them, but these modified phages can’t replicate. This means that they can’t spread to healthy tissue, unlike viruses that normally attack humans. Hajitou and his team developed this phage by giving it genetic instructions that enable it to bind to a protein often found on the outside of cancer cells, and then inject its DNA into them. They also gave it genes that code for toxic proteins. Once injected with these genes, cancer cells begin to make the proteins, and then die.
4-23-19 Medicaid expansion may help shrink health gaps between black and white babies
Better access to health care is reducing disparities, a study of 15.6 million infants finds. Black babies in the United States are twice as likely as white infants to be born at low birth weight, and 1.5 times as likely to be born prematurely. But states that expanded Medicaid health care coverage as part of the 2010 Affordable Care Act may be shrinking that racial health gap, a study finds. Researchers analyzed birth certificate data in 18 states plus Washington, D.C., that had expanded Medicaid coverage to include more low-income citizens from 2014 to 2016, and in 17 states that did not. The team compared health outcomes of about 15.6 million babies born from 2011 to 2016 of all ethnicities across four categories: very preterm (born before 37 weeks), preterm (before 32 weeks), very low birth weight and low birth weight. Disparities in health outcomes for black and white babies across all four categories shrank following the expansion of Medicaid in affected states, but were unchanged or increased in nonexpansion states. For instance, for low birth rate babies, black babies fared better so the gap between black and white infants decreased 7.7 percent for expansion states, but increased 4 percent in nonexpansion states, the team reports April 23 in JAMA. Premature or small babies can go on to have healthy lives, but are at a higher risk of infant mortality and of long-term health problems, compared with full-term babies born at a healthy weight. The new research shows that improved access to health care translates to thousands of black lives saved or transformed, says pediatrician Consuelo Beck-Sagué of Florida International University in Miami, who was not part of the study.
4-23-19 Innovative child malaria vaccine to be tested in Malawi
A large-scale pilot of what has been called the world's first malaria vaccine to give partial protection to children has begun in Malawi. The RTS,S vaccine trains the immune system to attack the malaria parasite, which is spread by mosquito bites. Earlier, smaller trials showed that nearly 40% of the 5-to-17-month-olds who received it were protected. Malaria cases appear to be on the rise again after a decade of success in combating the deadly disease. "This is a landmark moment for immunisations, malaria control, and public health," Dr Kate O'Brien, Director of Immunisation and Vaccines at the World Health Organization, told the BBC. According to the most recent annual figures, global malaria cases are no longer falling, sparking concerns about its resurgence. Malawi is the first of three countries chosen for the pilot to roll out the vaccine. It aims to immunise 120,000 children aged two years and below. The other two countries, Ghana and Kenya, will introduce the vaccine in the coming weeks. The three countries were picked because they already run large programmes to tackle malaria, including the use of bed nets, yet still have high numbers of cases. Malaria kills some 435,000 people around the world each year, the majority of them children. Most of these deaths are in Africa, where more than 250,000 children die every year, according to the World Health Organization (WHO). Dr O'Brien said that malaria is "a really difficult disease to develop a vaccine against". An early trial of the vaccine began in 2009. "There were seven countries participating in a large trial where over 15,000 children participated," Dr David Schellenberg, who has been working on the development of the vaccine with the WHO, told the BBC's Newsday programme. "[The trial] showed pretty clearly that this vaccine is safe and it is efficacious in terms of its ability to prevent clinical malaria episodes and also severe malaria episodes," he said.
4-23-19 How an obscure sexually transmitted parasite tangoes with the immune system
Trichomonas vaginalis also enlists helpers to battle other microbes. Frances Mercer runs a fight club. In one corner, the parasite Trichomonas vaginalis, which causes a widespread sexually transmitted infection that many people have never heard of. In the other corner are neutrophils, the immune system cells best equipped to take down the aggressor. Watching the two battle it out, Mercer, an immunoparasitologist at California State Polytechnic University in Pomona, has learned a lot about the parasite. And she’s shown exactly how neutrophils manage to take down T. vaginalis — using a maneuver that scientists didn’t even know the immune cells possessed. A focus on T. vaginalis has been a long time coming. In 2016, the parasite was responsible for about 156 million worldwide cases of the sexually transmitted infection called trichomoniasis in men and women. In the United States, trichomoniasis is the third most common sexually transmitted infection after HPV, or human papillomavirus, and herpes. Today, scientists are just beginning to get a handle on how the parasite causes trouble — including increasing risk for HIV infection, infertility and preterm delivery — and how the human immune system fights back. Complicating the picture is the fact that T. vaginalis doesn’t work alone. Other microbes living inside the vagina, and some inside the parasite itself, get into the fray. The infection “is not taken very seriously; it’s thought of as making women a bit itchy down there,” says Jane Carlton, a parasitologist at the New York University Center for Genomics and Systems Biology. As its name suggests, T. vaginalis colonizes the vagina, but it can also find a home in the urethra, which carries urine, in both men and women.
4-23-19 ‘An Elegant Defense’ explores the immune system’s softer side
A new book overturns simplistic notions of our body’s "war machine". We like to think of the immune system as our own personal military, ready to attack foreign invaders. Slice your finger, and immune cells rush in to destroy rogue pathogens. But it’s misleading to think of the immune system as solely a war machine. It must also keep the peace, assessing each threat and, in many cases, deciding to stand down. (This often-overlooked peacekeeping role is what allows the microbiome, the collection of microorganisms that live in and on the body, to thrive.) In An Elegant Defense, Pulitzer Prize–winning journalist Matt Richtel argues that it is this ability — to differentiate friend from foe (or neutral party) and act accordingly — that makes the immune system so powerful and so elegant. “It is a system precisely and delicately tailored to stay in balance, keep the peace and do as little damage as possible to us and our surroundings,” he writes. And that balance is central to our health. An Elegant Defense offers a sweeping overview of immunology’s history, from Élie Metchnikoff’s observations in the 1800s of immune cells swarming splinters in starfish larvae to recent discoveries underpinning cancer immunotherapy. Richtel explains all of this science through the stories of four individuals deeply affected by their immune systems. Richtel’s childhood friend Jason Greenstein is battling a stubborn form of Hodgkin’s disease that seems to be invisible to his immune response. Bob Hoff contracted HIV in 1977, but his immune system managed to keep the virus in check. And the lives of Linda Segre and Merredith Branscombe have been radically altered by their overactive immune systems. Richtel, who covers science and technology for the New York Times, once joked that the paper’s writing will always remain “dry and lifeless.” But that’s not Richtel’s style. The prose in An Elegant Defense is vibrant, conversational, direct and often funny. He introduces one story like this: “A Dane, an Argentinian Jew and a German walk into a research lab…”
4-22-19 Ancient sculptors made magnetic figures from rocks struck by lightning
Guatemalan ‘potbelly’ sculptures suggest people knew about magnetism more than 2,000 years ago. People living at least 2,000 years ago near the Pacific Coast of what’s now Guatemala crafted massive human sculptures with magnetized foreheads, cheeks and navels. New research provides the first detailed look at how these sculpted body parts were intentionally placed within magnetic fields on large rocks. Lightning strikes probably magnetized sections of boulders that were later carved into stylized, rotund figures — known as potbellies — at the Guatemalan site of Monte Alto, say Harvard University geoscientist Roger Fu and his colleagues. Artisans may have held naturally magnetized mineral chunks near iron-rich, basalt boulders to find areas in the rock where magnetic forces pushed back, the scientists say in the June Journal of Archaeological Science. Predesignated parts of potbelly figures — which can stand more than 2 meters tall and weigh 10,000 kilograms or more — were then carved at those spots. Potbellies represented dead but still revered ancestors of high-ranking families, suspects art historian Julia Guernsey of the University of Texas at Austin. Sculptures that repelled magnetized objects would have been seen as demonstrating the presence and authority of deceased ancestors in rapidly expanding societies (SN: 6/1/13, p. 12), she suggests. Fu’s results also indicate that Mesoamericans attributed special powers to certain body parts, such as the face and midsection, Guernsey adds. The researchers studied 11 potbelly sculptures, six heads and five bodies, now displayed in a Guatemalan town. At least 127 such sculptures have been found at sites in Mesoamerica, an ancient cultural region that runs from central Mexico through much of Central America.
4-21-19 When anxiety happens as early as preschool, treatments can help
Young children may need a different kind of therapy to accommodate their developing brains. When Molly was 10 months old, her parents took her to a Halloween party with other young families. While the other babies explored their surroundings, Molly sat and watched. She’s always been cautious, says Molly’s mom, Rachel. Early on, though, the little girl’s shyness didn’t raise red flags. By the time Molly turned 4, however, life was getting harder — for everyone. Even though she loved to dance, Molly refused to engage in class without her parents nearby. She clung to her mom in public and became whiny and upset. The family began avoiding outings. Dance classes ceased, as did gymnastics. Playdates were rare and had to be held in Molly’s home. “Our world was getting smaller,” says Rachel, who asked to use only first names to protect her daughter’s privacy. In kindergarten, Molly’s anxiety escalated. Parents were supposed to drop their children off in front of the school so a teacher could walk them inside, but Molly struggled. “She would … chase us into the road,” Rachel says. Concerned for Molly’s safety, school administrators eventually gave the family permission to escort her inside. Once at school, Molly latched onto another girl, trying hard to dress exactly like her. It seemed to Rachel that Molly “wanted to be invisible.” Fears about going to school consumed Molly, who felt sick every night before school. “She had stomachaches,” Rachel says. “She was constipated.” Molly’s issues may appear extreme, but anxiety is surprisingly common among young children. Estimates vary widely, but most studies indicate that 10 to 20 percent of U.S. preschoolers suffer from one of several anxiety disorders. When anxiety hits young, it often holds on into adolescence and adulthood. Children diagnosed with clinical anxiety early have double the risk of anxiety and substance abuse in their teen years, compared with children who don’t have an anxiety disorder. That later anxiety has been linked to missed school, drug abuse, depression and even suicide.
4-21-19 The medical right not to know
Do you have a right to ignorance about your health?. familiar scenario: As part of having your cholesterol checked, your clinician also orders a standard blood panel — a red blood-cell count, and then a breakdown showing the proportions of five types of white blood cells. Less familiar: Your cholesterol is fine (congratulations), but the white blood-cell counts are off, with values that could mean something fairly mild, such as a viral infection, or point to a serious, potentially fatal problem, such as cancer. Would you want your clinician to tell you about this abnormal finding? If you said "yes," then you are expressing your right to know about the result. If you said "no," then you are expressing the opposite: the right not to know. In most cases, the clinician would tell the patient about such an abnormal finding and discuss it. But what if the finding turned up in samples donated for medical research instead of taken for medical testing? That's exactly what's happened in Iceland. In the 1990s, researchers began collecting donated samples from the country's genetically distinct population. The chief officer of the company collecting and analyzing these samples — which come from half the country's residents — says that 1,600 of them suggest a risk for a deadly cancer. But the government is keeping Kári Stefánsson, a neurologist, and his company, deCODE Genetics, from telling the donors. Why? The nation's privacy laws and the concept of the right not to know are in the way. Back when the collection started, deCODE did not get explicit consent from those donating samples to share such information with them. Indeed, the company was founded in 1996, and one of the cancer-related gene variants in the samples, BRCA2, was discovered only the year before. It would have been hard to foresee how genetic samples might be so revealing 20 years down the line.
4-21-19 Huge dinosaur may have stood on its toes with fleshy pads for balance
A 24-tonne dinosaur appears to have stood on its tip toes. A fossil analysis reveals how its bone structure meant it couldn’t have flattened its feet on the ground, and instead may have stood on its toes with fleshy pads for balance. Rhoetosaurus brownie lived around 170 million years ago and was a type of sauropod dinosaur. Sauropoods walked on all fours and had long necks and tails. They are the largest land animals ever known to exist and the group includes Diplodocus. Andréas Jannel at the University of Queensland in Australia and her colleagues analysed a foot fossil of R. Brownie to see how it could have supported itself. They found its bone structure meant its heels couldn’t touch the ground without breaking its ankles and that it lacked the skeletal structure associated with hooves. This means that despite being so enormous, R. Brownie may have walked on its tiptoes. Footprints of sauropods that lived a few million years later have suggested these giants had feet that resemble modern elephants. Elephants stand on their toes and have a thick layer of soft tissue that touches the ground. R. brownie was five times the size of an elephant, so may have needed similar soft padding to support they humongous body and give them balance, says Jannel. However, there is no direct fossil evidence of such a heel pad on R. brownie or other sauropods because soft tissue is rarely preserved. Sauropods underwent rapid body growth from their ancestors. As a result, not all parts of their bodies were prepared for such an expansion, says Denver Fowler at the Dickinson Museum Center in North Dakota. To adapt, sauropods had to evolve new weight support systems, and heel pads would have been very useful, he says.
4-19-19 ‘Invisible Women’ spotlights a gaping and dangerous gender data gap
A new book explains how the failure to study women harms their health. The recent cancellation of the first all-female spacewalk occurred after the publication of Caroline Criado Perez’s Invisible Women. But the news — the lack of enough space suits for the women, suits which weren’t designed for the shape of women’s bodies in the first place — would fit right in to Criado Perez’s scathing takedown of a world that ignores the needs of half the population by not using or even gathering data on women. This gaping gender data gap, Criado Perez convincingly argues, is costing women their health and their lives. From city infrastructure to car safety to health, journalist Criado Perez details what’s at stake when (largely male) planners, politicians and researchers turn a blind eye to women’s needs. For example, many cities have been designed to accommodate cars, a choice that favors men over women, who are more likely to walk or take public transportation. Criado Perez argues that this bias toward cars may lead to more injuries for women when it snows and sidewalks aren’t prioritized for clearing. A study of pedestrian injuries in Sweden found that 79 percent took place in winter, and 69 percent of people injured in single-person incidents, such as a fall, were women, Criado Perez writes. When women do drive, they do so in vehicles with safety features designed to protect men. Women tend to be shorter than men, and this means they need to sit farther forward in a car to reach the pedals. Yet this is not considered the standard seating position, making women who shift forward “out of position” drivers, Criado Perez notes. This necessity, unaccounted for in a car’s design, puts women at greater risk of injury in frontal crashes. And the risk extends to collisions from behind, as today’s seats are too firm to protect women from whiplash, throwing them forward faster than men. The result? Although men are more likely than women to be in a car crash, a woman in a collision “is 47% more likely to be seriously injured than a man … [and] 17% more likely to die,” Criado Perez says.
4-19-19 The downside of online learning
More and more students are taking online courses. But new research shows this might not be a good thing. For more and more of today's university students, screen time is competing with seat time. According to the most recent statistics (from 2016–17), 33 percent of college students take at least one online class, 17.6 percent mix online and in-class coursework, and 15.4 percent exclusively take online classes. Each statistic represents an increase over the year prior, a trend that has continued since 2011. Advocates of online education are quick to celebrate this increase, but the rise of screen time in higher education may harbor some detrimental consequences. Online courses have obvious benefits: They cut costs and are popular with working students seeking scheduling flexibility. At a number of campuses they also increase educational access. The Orlando Sentinel reports, for example, that the University of Central Florida, a school with an extensive online catalog, can serve 66,000 students due to that catalog, as opposed to the 40,000 its physical campus can accommodate. Thomas Cavanagh, UCF vice provost for digital learning, explains that demand for online offerings is at an ever-increasing level. "Students," he says, "are clearly voting with their behaviors." But the educational benefits of online courses are less clear. A Brookings Institution report found that students taking online courses "perform substantially worse than students in traditional in-person courses and that experience in these online courses impacts performance in future classes and likelihood of dropping out of college as well." The New York Times opinions page editorialized in 2013 that the "online revolution" was "distressing," threatening as it does to "shortchange the most vulnerable students." A new study out of Kent State suggests a specific reason for the problems plaguing online coursework: multitasking. In a survey of 452 undergraduates at public universities in the American Midwest, researchers confirmed "significantly greater multitasking behavior in online versus face-to-face courses." Students enrolled online reported higher rates of texting, emailing, checking in with online social networks, watching videos — none of these activities related to class — while also playing video games and listening to music. The study's lead author, Andrew Lepp, was inspired to explore the topic of online-course multitasking when he witnessed a student taking a biology class in his library basement while streaming a Netflix video. Lepp notes that his study's findings have "immediate implications" for undergraduate education, in part because "an abundance of research demonstrates that multitasking during educational activities significantly reduces learning." On this point, the evidence is quite strong, if not alarming. By nearly every measure, multitasking is bad for the brain — and may even damage it. A University of London study found that students who multitasked experienced a drop in IQ comparable to the mental decline caused by staying up all night or smoking pot. And this drop may be more than temporary. A 2014 study published in PLoS One found that multitasking might permanently diminish the brain's density. Specifically, researchers discovered that people with a high "Media Multitasking Index" — that is, big multitaskers — "had smaller grey matter density" in the anterior cingulate cortex section of the brain. Needless to say, this kind of mental development runs contrary to the most basic mission of higher education.
4-19-19 The herbal supplement kratom comes with risks
The supplement may be behind a small but growing number of deaths. Kratom, an herbal supplement available at vape shops and online stores, has been linked to 91 deaths over 18 months from July 2016 to December 2017, according to a report by the U.S. Centers for Disease Control and Prevention. Those deaths made up less than 1 percent of the 27,338 overdose fatalities analyzed for the report, released online on April 12. Although small, the numbers point to increasing numbers of people using the plant to combat pain, depression and even opioid addiction. Interest in, and exposure to, kratom is apparently rising. “We’d see about 10 cases a year, and now we’re seeing hundreds,” says toxicologist Henry Spiller of the Central Ohio Poison Center in Columbus. The supplement is mashed leaves from the tropical tree Mitragyna speciosa, a coffee cousin that grows in the warm, wet forests of Southeast Asia. Pulverized leaves create a green powder that can be dissolved in tea, packed into pill capsules or extracted into alcohol. Traditionally, workers chew the leaves in search of a mild stimulant effect during the day, and then drink tea to relieve pain, says pharmacologist and toxicologist Oliver Grundmann of the University of Florida in Gainesville. In a survey of about 8,000 kratom users in the United States, 68 percent used kratom for pain, and 66.5 percent used it for emotional or mental conditions, Grundmann reported in Drug and Alcohol Dependence in 2017. A smaller fraction of people used kratom to help with drug dependency.
4-18-19 A drug-resistant germ goes global
A deadly drug-resistant fungus is quietly spreading through hospitals around the world. Candida auris, which infects people with weakened immune systems, has wreaked havoc in hospital units in Spain and Britain; taken root in India, Pakistan, and South Africa; and been added to the Centers for Disease Control and Prevention’s list of “urgent threats.” There have been at least 587 cases in the U.S. since 2013; nearly half of patients who contract C. auris die within 90 days. While public health officials have long warned that excessive use of antibiotics is creating drug-resistant “superbugs,” the spread of C. auris shows that there’s a similar problem with fungi. An estimated 700,000 people worldwide die from drug-resistant infections each year. Yet because hospitals are reluctant to disclose outbreaks for fear of being seen as infection hubs, the extent of the problem is not fully clear. Scientists can’t even establish where C. auris originated. “It is a creature from the black lagoon,” Tom Chiller, head of the CDC’s fungal branch, tells The New York Times. “It bubbled up and now it is everywhere.”
4-18-19 Measles spreads
Measles cases in Africa are up 700 percent so far this year, compared with the same period in 2018, the United Nations reported this week. The worst outbreak is in Madagascar, where tens of thousands of people have been sickened and 800 have died since September. Measles cases have quadrupled globally in the past year, largely because of difficulties obtaining vaccines in poor countries and unfounded safety concerns in rich ones. Worldwide, there were 112,163 measles cases reported to the World Health Organization in the first three months of this year, compared with 28,124 cases during the same period in 2018. But the WHO says the true number of cases is much larger, because only about 1 in 10 infections is reported. Measles kills about 100,000 people, mostly children, every year.
4-18-19 Men with beards
The hirsute, with new research showing that men with beards carry more bacteria than dogs do in their fur, with nearly 40 percent of beards tainted with microbes that are hazardous to human health. “Dogs can be considered as clean compared with bearded men,” said Professor Andreas Gutzeit, of Switzerland’s Hirslanden Clinic.
4-18-19 Bad diets kill more than smoking
Unhealthy diets cause more deaths worldwide than smoking or high blood pressure, new research has found. And while the researchers found that consumption of red meat, sugary drinks, and other unhealthy options play a part in that toll, they concluded that the majority of these deaths are the result of people not eating enough healthy foods. Covering 195 countries between 1990 and 2017, the Global Burden of Disease study tracked consumption of 15 dietary elements. The main risk factors for premature death, researchers found, were eating too few fruits, vegetables, nuts, seeds, and whole grains and consuming too much salt. Overall, researchers estimate, poor diet accounts for 10.9 million deaths around the world, a fifth of total preventable fatalities. By comparison, tobacco is linked to 8 million deaths and high blood pressure to 10.4 million. Lead author Ashkan Afshin, from the University of Washington, says health authorities should focus on encouraging healthy eating rather than trying to persuade people to cut down on sugar, fat, or even salt. “Generally in real life people do substitution,” he tells The Guardian (U.K.). “When they increase the consumption of something, they decrease the consumption of other things.”
4-18-19 Supplements may be harmful
Dietary supplements don’t reduce your risk of early death, and may even be harmful in large quantities, reports NBCNews.com. Researchers from Tufts University examined data from a health survey involving more than 30,000 people ages 20 and older. After accounting for lifestyle factors, they found that people who ingested adequate amounts of magnesium, zinc, and vitamins A and K had a lower risk of death over the study period—but only when those nutrients came from food rather than supplements. Furthermore, the participants who took more than 1,000 mg of calcium supplements a day had a higher risk of death from cancer, while those who took more than 400 IU of vitamin D supplements had a higher risk of death from any cause. “It’s becoming more and more clear,” says study co-author Fang Fang Zhang, “that the regular use of dietary supplements is not beneficial in reducing the risk of mortality among the general population.”
4-18-19 We must all work to avoid disputes over the care of very ill children.
New advice will help reduce conflict between medical professionals and the parents of desperately sick children, says Mike Linney. Modern medicine has the power to enhance and prolong the lives of seriously ill children. This is clearly good news, but sometimes it leads to ethical dilemmas. If health professionals and parents cannot agree on what is in a child’s best interest, the decision may be taken to court. Recently, there have been several high-profile disputes, such as the one between the parents of Alfie Evans and Alder Hey Children’s Hospital in Liverpool, UK, over whether or not to withdraw life support. Parents are right to fight for their children. They want what is best for them and health professionals understand that. However, the rise of the internet and social media has made conflict more likely by giving families in desperately sad situations quick and easy access to information about new treatments – some robustly tested and available in the UK and some not. This extends hope to families, which can be helpful. But it can also make matters worse when parents want their children to have treatments that doctors consider inappropriate or likely to cause more harm than good. It is, for instance, what led to a court battle in 2017 between Great Ormond Street Hospital for Children in London and the parents of Charlie Gard, who wanted to take their son to the US for treatment. Where such conflicts occur, they can have profound mental and physical effects on all involved. In some cases, we have even seen protests on hospital sites and abusive messages directed at clinicians – actions that have sent shock waves through the medical community.
4-18-19 A genetic scorecard could predict your risk of being obese
Critics counter that genetics are only partly to blame for too much weight gain. There’s a new way to predict whether a baby will grow into an obese adult. Combining the effect of more than 2.1 million genetic variants, researchers have created a genetic predisposition score that they say predicts severe obesity. People with scores in the highest 10 percent weighed, on average, 13 kilograms (about 29 pounds) more than those with the lowest 10 percent of scores, the team reports April 18 in Cell. The finding may better quantify genes’ roles in obesity than previous prediction scores, but still fails to account for lifestyle, which may be more important in determining body weight, other researchers say. Still, the study shows that “your genetics really start to take hold very early in life,” says coauthor Amit Khera, a cardiologist at Massachusetts General Hospital and the Broad Institute of MIT and Harvard. Weight differences showed up as early as age 3, and by age 18, those with the highest scores weighed 12.3 kilograms more on average than those with the lowest scores, Khera and his colleagues found. Some people with high genetic scores had normal body weights, but those people may have to work harder to maintain a healthy weight than others, he says. People with the highest scores were 25 times more likely to have severe obesity — a body mass index (BMI) greater than 40 — than those with the lowest scores. BMI is a measurement of body fat based on height and weight. A BMI of 18.5 (calculated as kilograms per meters squared of height) to 24.9 is considered healthy. BMIs 30 and above are considered obese. The nearly 13-kilogram difference between people dealt a good genetic hand versus those dealt a bad one equals about five BMI points. “Five points is a lot,” Khera says. “That’s what takes you from normal to obese, from obese to severely obese.” High scores were also associated with increased risk of heart disease, diabetes, high blood pressure and stroke.
4-18-19 Dog owners are more likely to get the recommended amount of exercise
It may be a dog-eat-dog world, but our furry friends bring at least one important health benefit: getting more exercise. In news that will surprise few dog owners, researchers found that those with pet pooches are much more likely to meet weekly targets for time spent engaging in physical activity. The UK government’s guidelines recommend that adults spend at least 150 minutes a week doing moderate-intensity activities, such as brisk walking or cycling. But only 66 per cent of men and 58 per cent of women in England achieve that benchmark. Carri Westgarth at the University of Liverpool, UK, and her colleagues surveyed 385 households in north west England, which included 191 dog-owning adults, 455 adults without dogs, and 46 children. To check the accuracy of people’s self-reported figures, 28 of the adults also wore an accelerometer for a week to track their activity levels. According to the self-reported data, 80 per cent of dog owners met the weekly physical activity target, compared with 62 per cent of non-dog owners. The accelerometers showed that dog walkers clocked up 2000 more steps and 13 more minutes of moderate-to-vigorous physical activity a day than non-dog owners. Dog walking does not appear to replace other forms of exercise – in fact, dog owners are more likely to go running or jogging than non-dog owners. The results show a bigger effect of having a dog on activity levels than other studies have found in the US and Australia. That might be because dog owners in warmer climates let their dogs roam freely outside, and don’t make as much of an effort to walk them. In the UK, where bad weather often makes outdoor activities less enticing, having a dog may be the best way to encourage adults to exercise, says Westgarth. “If the weather’s not good, people still dog walk.”
4-18-19 Evidence of rabbits in UK in Roman times, say academics
Rabbits have been hopping around the UK since Roman times, experts have been able to prove for the first time. Scientific tests on a rabbit bone, found at Fishbourne Roman Palace in West Sussex, have shown the animal was alive in the first century AD. The 1.6in (4cm) piece of a tibia bone was found in 1964 but it remained in a box until 2017, when a zooarchaeologist realised that it came from a rabbit. Academics believe the animal could have been kept as an exotic pet. Analysis, including radiocarbon dating, was carried out by researchers at the universities of Exeter, Oxford and Leicester. Rabbits are native to Spain and France and it had been thought they were introduced to Britain during the medieval period. Prof Naomi Sykes, from the University of Exeter, said there have been many previous claims of discoveries of Roman rabbits, and even some from the Bronze Age, but they had not been backed up by evidence. "The bone fragment was very small, meaning it was overlooked for decades, and modern research techniques mean we can learn about its date and genetic background as well," she said. Researchers say they believe the rabbit was kept as a pet, as the signature in its bones suggests it ate its own faecal pellets. "When they are in a hutch they tend to eat their own poo, and that gives them a really interesting signature in their bones, wild rabbits don't do that to the same extent," said Prof Sykes. She added: "This is a tremendously exciting discovery and this very early rabbit is already revealing new insights into the history of the Easter traditions." It is not clear when, why or how the rabbit became linked to Easter. Rabbits usually give birth to a big litter of babies (called kittens), and so they became a symbol of new life. The first historical mention of an "Easter Bunny" is actually an Easter hare, and was found in a German text from 1682. Some believe the association is due to the spread of Christian religious beliefs and Paganism, when Emperor Constantine merged Pagan rituals with Christian festivals.
4-18-19 'Giant lion' fossil found in Kenya museum drawer
A new species of giant mammal has been identified after researchers investigated bones that had been kept for decades in a Kenyan museum drawer. The species, dubbed "Simbakubwa kutokaafrika" meaning "big African lion" in Swahili, roamed east Africa about 20 millions years ago. But the huge creature was part of a now extinct group of mammals called hyaenodonts. The discovery could help explain what happened to the group. Hyaenodonts - so called because their teeth resemble those of a modern hyena - were dominant carnivores more than 20 million years ago, National Geographic reports. But they are not related to hyenas. "Based on its massive teeth, Simbakubwa was a specialised hyper-carnivore that was significantly larger than the modern lion and possibly larger than a polar bear," researcher Matthew Borths is quoted by AFP news agency as saying. In 2013 he was doing research at the Nairobi National Museum when he asked to look at the contents of a collection labelled "hyenas", National Geographic says. The creature's jaw and other bones and teeth had been put there after being found at a dig in western Kenya in the late 1970s. Mr Borths teamed up with another researcher, Nancy Stevens, and in 2017 they began analysing the unusual fossil specimens. Their findings were reported in the Journal of Vertebrate Paleontology this week.
4-17-19 Pig brains partially revived four hours after death
US scientists have partially revived pig brains four hours after the animals were slaughtered. The findings could fuel debate about the barrier between life and death, and provide a new way of researching diseases like Alzheimer's. The study showed the death of brain cells could be halted and that some connections in the brain were restored. However, there were no signals from the brain that would indicate awareness or consciousness. The surprise findings challenge the idea that the brain goes into irreversible decline within minutes of the blood supply being cut off. Thirty-two pig brains were collected from an abattoir. Four hours later the organs were connected to a system made by the team at Yale University. It rhythmically pumped (to mimic the pulse) a specially designed liquid round the brain, which contained a synthetic blood to carry oxygen and drugs to slow or reverse the death of brain cells. The pig brains were given the restorative cocktail for six hours.The study, published in the journal Nature, showed a reduction in brain cell death, the restoration of blood vessels and some brain activity. The researchers found working synapses - the connections between brain cells that allow them to communicate. The brains also showed a normal response to medication and used up the same amount of oxygen as a normal brain. This was all 10 hours after the pigs were decapitated. Crucially there was no sign of the brain-wide electrical activity in an electroencephalogram (EEG brain scan) that would signal awareness or perception. Fundamentally they were still dead brains. The research transforms ideas about how the brain dies, which many thought happened quickly and irreversibly without a supply of oxygen. Prof Nenad Sestan, a professor of neuroscience at Yale University, said: "Cell death in the brain occurs across a longer time window that we previously thought. "What we are showing is the process of cell death is a gradual, stepwise process. "And that some of those processes can be either postponed, preserved or even reversed."
4-17-19 Dead pig brains bathed in artificial fluid showed signs of cellular life
Nerve cell activity was detected hours after death. Scientists have restored cellular activity to pig brains hours after the animals’ death — an unprecedented feat. This revival, achieved with a sophisticated system of artificial fluid, took place four hours after the pigs’ demise at a slaughterhouse. “This is a huge breakthrough,” says ethicist and legal scholar Nita Farahany of Duke University, who wasn’t involved in the research. “It fundamentally challenges existing beliefs in neuroscience. The idea of the irreversibility of loss of brain function clearly isn’t true.” The results, reported April 17 in Nature, may lead to better treatments for brain damage caused by stroke or other injuries that starve brain tissue of oxygen. The achievement also raises significant ethical puzzles about research on brains that are not alive, but not completely dead either. In the study, the brains showed no signs of the widespread neural activity thought to be required for consciousness. But individual nerve cells were still firing. “There’s this gray zone between dead animals and living animals,” says Farahany, who coauthored a perspective piece in Nature. The experiments were conducted on pigs that had been killed in a food processing plant. These animals were destined to become pork. “No animals died for this study,” the authors of the new work write in their paper. After decapitation, about 300 pig heads were put on ice and transported to a Yale University laboratory, where researchers surgically removed the brains. Four hours post mortem, researchers put 32 of these brains in an artificial system known as BrainEx — a chamber with specially designed blood replacement fluid that pumps through the blood vessels, delivering oxygen, sugar and other sustaining ingredients at body temperature to keep the brains operating.Description
4-17-19 A virus we thought was harmless to humans may worsen cystic fibrosis
People with cystic fibrosis may experience more severe bacterial infections if they carry a certain type of virus – even though the virus actually targets bacteria. The so-called filamentous bacteriophage seems to prevent antibiotics from reaching the bacteria, making infections harder to treat. Cystic fibrosis is a genetic disease that leads to the build-up of thick mucus in organs including the lungs. The mucus can provide a breeding ground for harmful bacteria, such as Pseudomonas aeruginosa. Elizabeth Burgener at Stanford University, California, and her colleagues tested mucus samples taken from 58 people who have cystic fibrosis and a P. aeruginosa infection. They found that 21 of them – 36 per cent – carried bacteria-infecting viruses called filamentous bacteriophages. “We know bacteriophages exist everywhere,” says Burgener, but they are often overlooked by health researchers because they don’t target human cells. What’s more, those who carried the virus had significantly more P. aeruginosa in their mucus than non-carriers. And some of this P. aeruginosa seemed to be resistant to three of the common antibiotics used to treat such infections. Filamentous bacteriophages are known to be able to bind to other molecules in the mucus, such as DNA and proteins, to form a very viscous film. The film serves as a shield that antibiotics can’t penetrate, says Burgener, which may be why the P. aeruginosa appears drug-resistant in the presence of the virus. “There is a need to take this bacteriophage more seriously,” says Joanna Goldberg at Emory University in Georgia. Antibiotic resistance is a major concern for people with cystic fibrosis because they are left with fewer options to treat life-threatening infections. Goldberg suggests doctors may need to test for the presence of the virus before deciding which type of antibiotics to use.
4-17-19 Viewing media coverage of traumatic events may fuel long-term distress
When something terrible happens in the world, it’s not uncommon to scroll through social media or flip through television channels in search of news coverage. But such media exposure may fuel post-traumatic stress symptoms for as much as two years afterwards – and could also drive someone to consume further distressing media. “With high-consequence events where we don’t know why they happened, there’s a fundamental drive to want to consume information until you get your head around it,” says Kenneth Lachlan at the University of Connecticut. “It may be a function of threat avoidance or wanting to return to some kind of rational understanding of the world around us.” Roxane Silver at the University of California, Irvine, and her colleagues surveyed a representative sample of more than 4400 US residents in the days following the 2013 Boston Marathon bombing. Each person was also asked how many hours of related media coverage they consumed in three follow-up periods: six months after the bombing, on its second anniversary and five days after the 2016 mass shooting in the Pulse nightclub in Florida. After the first survey, the team found that those previously diagnosed with mental health conditions or who had experienced violence first hand consumed more media coverage about the Boston bombing, and also experienced more symptoms of post-traumatic stress. On average, the people surveyed consumed about 6 hours of media a day about the Boston bombing immediately after the event and a little more than 3 hours per day of media about the Pulse shooting. Those who sought out more media about the bombing – whether or not they had a history of mental health conditions – were more likely to have trauma-related stress symptoms, such as upsetting thoughts, flashbacks and emotional distress, six months later. Two years after the bombing, such people were also more likely to worry about other events of mass violence or terrorism occuring in the future.
4-17-19 Ancient urine reveals early prehistory of domestic sheep and goats
Early farmers living in Turkey increased their reliance on domestic sheep and goats over a period of 1000 years. The shift in practices has been revealed by the animals’ urine, which is preserved in the soil as distinctive salts.. “For the first time, we can get a quantitative estimate of the number of organisms it would take to produce these salts,” says geochemist Jordan Abell of Columbia University in New York. This offers an idea of the herd sizes at the time, he says. Abell and his colleagues studied a Stone Age site called As¸ikli Höyük in Turkey, which was discovered in the 1960s and has been excavated on and off since the 1980s. It was occupied between about 10,400 and 9300 years ago. The people living there built oval houses of wattle and daub, which were closely packed together. As¸ikli Höyük is one of many places in and around the Middle East where people gradually abandoned hunter-gathering to focus on farming. Previous excavations have revealed an increasing reliance on sheep and goats for meat, including evidence that young male animals were selectively culled. Crops including wheat and lentils were important too. To track the growth of the animal herd, the team studied salts rich in sodium, chlorine and nitrate, which were preserved in the layers of sediment. Most of these salts seem to have come from urine, either from humans or their domestic animals. The team first subtracted other potential contributors, such as wood ash. Then they looked up how much the average human or sheep urinates per day. The question, says Abell, was: “how many organisms would it take to produce that much salt?” The team tracked the preserved urine through four layers of sediment, which span 1000 years of occupation. This allowed them to estimate how many large animals (including humans) lived in As¸ikli Höyük at different times.
4-17-19 Statisticians want to abandon science’s standard measure of ‘significance’
Here’s why “statistically significant” shouldn’t be a stamp of scientific approval. In science, the success of an experiment is often determined by a measure called “statistical significance.” A result is considered to be “significant” if the difference observed in the experiment between groups (of people, plants, animals and so on) would be very unlikely if no difference actually exists. The common cutoff for “very unlikely” is that you’d see a difference as big or bigger only 5 percent of the time if it wasn’t really there — a cutoff that might seem, at first blush, very strict. It sounds esoteric, but statistical significance has been used to draw a bright line between experimental success and failure. Achieving an experimental result with statistical significance often determines if a scientist’s paper gets published or if further research gets funded. That makes the measure far too important in deciding research priorities, statisticians say, and so it’s time to throw it in the trash. More than 800 statisticians and scientists are calling for an end to judging studies by statistical significance in a March 20 comment published in Nature. An accompanying March 20 special issue of the American Statistician makes the manifesto crystal clear in its introduction: “‘statistically significant’ — don’t say it and don’t use it.” There is good reason to want to scrap statistical significance. But with so much research now built around the concept, it’s unclear how — or with what other measures — the scientific community could replace it. The American Statistician offers a full 43 articles exploring what scientific life might look like without this measure in the mix.
4-16-19 Surprising ways the changing Earth shaped human evolution and society
From the development of our remarkable brains to the geographic divides in the way we vote, our shape-shifting planet has guided the path of humanity. HUMANITY today is actively reshaping the planet. Our appetite for natural resources and large-scale industrial activity is eradicating species, warming the oceans and disrupting the global climate on an unprecedented scale. So profound is our impact that some have called for the times we live in to be declared a new geological period: the Anthropocene, the age of humanity. But this ability to shape our environment on such a scale is a recent phenomenon. For most of our history, it is our environment that has shaped us. The physical features of the planet we live on enabled our species to arise, nurtured our remarkable brains, facilitated our spread across the planet and even encouraged the birth of the first cities. This is the remarkable story of the way Earth has moulded humanity, and how we have turned the tables to shape the world. Some 55.5 million years ago, Earth’s thermostat did something unexpected. In the space of 100,000 years, barely the blink of an eye on geological timescales, the temperature of the planet jerked up by between 5°C and 8°C, hovered for a bit, and then came back down. This brief planetary fever was hugely disruptive to life on Earth, driving the rapid evolution and divergence of whole new orders of animals, including our own. The principal culprit is thought to have been methane. As a powerful greenhouse gas, its presence in air makes our atmosphere trap more of the sun’s heat than it usually would, raising the temperature on the surface. Then, as now, huge deposits of methane lay on the sea floor, a by-product of decaying organic matter. Under the extreme pressures and low temperatures found at such depths, the gas became trapped within crystals of ice, safely locked away so long as the ice didn’t melt. In planetary terms, it was a barrel of gunpowder waiting for a match. The fateful spark is thought to have been a cluster of volcanic eruptions that peppered the atmosphere with enough carbon dioxide to cause an initial temperature rise. This, in turn, melted ice on the sea floor, causing methane to bubble up through the water and into the atmosphere, leading to a further temperature rise that melted yet more methane. The sweltering climate resulted in a burst of evolutionary diversification. The fossil record shows that ungulates, which include modern species like the cow, goat, pig, sheep, llama, camel and horse, first emerged during this period. These families of large herbivores are utterly critical to human societies around the world, providing not just a reliable source of meat, milk, hide, wool and leather, but also means of transport. We ride them, load them with packs and put them to work hauling carts or ploughs, all in the service of human development. But the most significant group of mammals that sprang up during this heatwave were the primates, the group that our own species belongs to. These early ancestors of ours, physically similar to lemurs, emerged and then rapidly dispersed across Asia, Europe and North America. But it was in the unique geology of East Africa that they took their first unsteady steps towards humanity.
4-16-19 Protein mania: The problem with the West’s latest diet obsession
THE bars and shakes were just the start. These days, there are high-protein cereals and high-protein yogurts, protein-fortified bread and cheese, protein-dense noodles and even ice creams loaded with the muscle-building macronutrient. What next, protein water? Well, yes actually. What will it be: still, sparkling or diet whey protein water? Stroll through your local supermarket today and you can hardly fail to notice the P word. Usually accompanied with “high” or “extra”, it seems to be emblazoned on the packaging of almost every foodstuff possible. Many of us have come to see protein as a sort of elixir of health. Not only does it apparently help you build muscle, it will guarantee weight loss by keeping you fuller for longer. Hence the desire for all those high-protein products. But is there actually any evidence to suggest that these foods and drinks are beneficial? Our bodies certainly demand protein. Together with fat and carbohydrate, it makes up the trio of basic macronutrients that humans need. Proteins are assembled from a repertoire of 20 amino acids, the basic building blocks of bone, muscle, skin and blood. It is especially important that we get enough of the eight so-called essential amino acids because, unlike the others, our bodies cannot make them. So the protein we get from our food is vital. We have known that for a long time. In recent years, however, many of us have become convinced we need more of the stuff. Even if you haven’t come across Weetabix Protein Crunch, say, or the Mars Hi Protein bar, the stats are instructive. The number of food and drink products launched with a high-protein claim in the UK rose by a whopping 498 per cent between 2010 and 2015, according to market research firm Mintel. More recently, in the three years to 2017, the proportion of new food and drink products launched with a high-protein claim jumped from 1.8 per cent to 4.3 per cent, and in the first three months of 2018 some 35 per cent of adults said they bought a non-sporting product branded as high in protein.
4-16-19 ‘Added sugar’ food labels may prevent heart disease and diabetes
The U.S. Food and Drug Administration announced the updated nutrition labeling in 2016. Nutrition label changes aimed at curbing America’s sweet tooth could have a sizable payoff for public health. to a food or drink, could help the average U.S. adult cut sugar consumption by around half a teaspoon a day. If that happens, the labeling change could prevent around 350,000 cases of cardiovascular disease and nearly 600,000 cases of diabetes over the next two decades, scientists report online April 15 in Circulation. The estimates come from a simulation, covering the years 2018 to 2037, that was based on a representative U.S. population of about 220 million adults aged 30 to 84, and that used data on sugar intake from a national health and nutrition survey. The updated sugar labeling is part of a series of nutritional label changes announced by the U.S. Food and Drug Administration in 2016, to be fully implemented by 2021. The U.S. government also released updated dietary guidelines in 2016, recommending that people consume no more than 10 percent of their daily calories in added sugar (SN Online: 1/7/16). Added sugar accounted for 17 percent of an adult’s calorie intake, on average, in the United States in 2012, according to a study published in the Journal of the Academy of Nutrition and Dietetics. Consuming too much sugar, especially in the form of sugar-sweetened beverages, has been tied to an increased risk of cardiovascular disease and diabetes. This link may be due in part because the body becomes resistant to the glucose-regulating hormone insulin.
4-16-19 People with stress disorders like PTSD are at higher risk of heart disease
A new study looks beyond men and veterans to find the link. People coping with psychological trauma have a heightened risk of developing cardiovascular disease, a large-scale study finds. Researchers used national health registers to identify 136,637 Swedish patients with no history of cardiovascular disease who were diagnosed with a stress-related disorder — a cluster of mental health conditions, including post-traumatic stress disorder, triggered by acute trauma — from 1987 to 2013. The team compared each of these patients with siblings and with unrelated people of the same age and sex, both of whom had a clear bill of mental and heart health. In the patients’ first year after being diagnosed, those with a stress-related disorder had a 64 percent higher risk of developing cardiovascular disease than their siblings without a mental health diagnosis, and a 70 percent higher risk than unrelated patients, the scientists report. The cardiovascular disease accounted for included heart failure, arrhythmia, stroke, hypertension and heart attack. The study found that those with a stress-related disorder were most vulnerable in the year following their mental health diagnosis: They had four times the relative risk of heart failure compared with their siblings. After one year, the patients with a stress diagnosis had a 29 percent higher risk for all cardiovascular disease than their siblings. Over the course of 27 years, 10.5 percent of patients with stress-related disorders developed cardiovascular disease — compared with 8.4 percent of the sibling group and 6.9 percent of the general population group. The study, published April 10 in the British Medical Journal, builds on a growing body of research linking mental health with heart disease.
4-16-19 Statins may not lower cholesterol enough in half those who take them
A study of more than 165,000 people suggests that fewer than half of those who are prescribed statins reach the desired level of cholesterol within two years of starting to take the drugs. In England, doctors are recommended to prescribe statins to people deemed to be of a high risk of heart disease, with the goal of lowering their LDL cholesterol levels by 40 per cent or more. But the analysis, which looked at data from between 1990 and 2016, found that statins achieved this within two years in only 49 per cent of those taking them. Those who didn’t see their cholesterol drop by the target amount were found to be 22 per cent more likely to develop cardiovascular disease than those who did. The team behind the work say these people “will experience significantly increased risk” of heart disease in future. “These findings contribute to the debate on the effectiveness of statin therapy and highlight the need for personalised medicine in lipid management for patients,” the team, from the University of Nottingham, UK, write.Statins work by lowering blood cholesterol levels. Some researchers argue that there is no link between cholesterol levels in the blood and levels of atherosclerosis – the furring of the arteries that can lead to heart attacks – but this claim is strongly rejected by many cardiologists and cholesterol researchers. Metin Avkiran, at Kings College London, says statins are an “important and proven treatment for lowering cholesterol and reducing the risk of a potentially fatal heart attack or stroke”. Avkiran says people currently taking statins should continue to take them as prescribed. “Although this study suggests that not everyone who is prescribed statins manages to reduce their cholesterol sufficiently, it doesn’t explain why,” he says.
4-16-19 Men who have children later in life may prime their kids for longevity
MEN who have children later in life may pass on changes acquired from their environment, a phenomenon reminiscent of Lamarckian evolution. French naturalist Jean-Baptiste Lamarck thought that if organisms changed their bodies during their life to adapt to their environment, those changes could be passed to children. Giraffes stretching their necks to reach tall trees, and then passing longer necks on the next generation, is a classic example of this incorrect theory of evolution. We now know organisms evolve through random DNA mutations: giraffes with mutations that caused longer necks passed these changes to their offspring. But a study of children of older dads suggests it may be possible to pass adaptations to subsequent generations in other ways. Dan Eisenberg at the University of Washington in Seattle and his team have studied telomeres, stretches of repetitive DNA at the ends of our chromosomes. These shorten each time a cell divides, so usually get shorter over a lifetime. If telomeres get too short, cells may stop dividing or even die. A woman’s eggs are all made before she is born, but the cells in men’s testes divide throughout their lives. Because we inherit telomere lengths from the egg and sperm cells that make us, the children of older fathers should in theory have shorter telomeres, but they don’t. This is probably because an enzyme called telomerase, which extends telomeres by adding more DNA to them, is very active in the testes. Several studies have shown that sperm from older men have longer telomeres than average. This may enable older men to reproduce without having children with dangerously short telomeres. Because telomerase adds DNA to a chromosome, it may be possible that they pass this acquired, non-genetic trait – longer telomeres – to offspring. Studying the DNA of nearly 3000 grandparents, plus their children and grandchildren, Eisenberg’s team found that this may be the case. A child’s telomere length correlates with the age at which their fathers and grandfathers reproduced, Eisenberg told a meeting of the American Association of Physical Anthropologists in Ohio.
4-16-19 ‘Cities’ reveals common ground between ancient and modern urban life
A new book chronicles 6,000 years of metropolitan history. Ancient Rome’s Monte Testaccio and modern Tokyo’s Tsukiji fish market reveal a lot about the nature of cities. Monte Testaccio is a hill made of broken pottery in the middle of Rome. Around 2,000 years ago, people tossed empty wine and olive oil vessels onto what was then a garbage heap. Tokyo’s vast seafood emporium, also known as Toyosu Market, includes passageways where forklifts deposit and remove containers of every sea creature imaginable, as chefs and home cooks bid for the day’s catch. These metropolitan destinations illustrate how mass production and consumption of goods — along with public markets, complex infrastructure and trash — have always characterized cities, archaeologist Monica Smith writes in Cities. She argues that cities provide work and leisure opportunities that, once invented around 6,000 years ago, people couldn’t do without. Trash was part of the deal, along with poverty and pollution — all of which remain city challenges. Ancient human traits and behaviors contributed to cities’ rapid ascendance, even if it took a few hundred thousand years for agriculture and other cultural developments to spark that urban transition, Smith writes. As a restless, talkative species searching for meaning in the world, people eventually started building gathering spots for religious pilgrimages. One of the earliest such places was Göbekli Tepe in what’s now Turkey, dating back 10,000 years or more. Public structures there set the stage for farmers and herders to create the oldest known city, Tell Brak, about 4,000 years later in Syria. Cities everywhere have been organized in remarkably similar ways to provide jobs, entertainment and other features, the author holds. People have always been drawn to those benefits, both for survival and for excitement, she writes.
4-16-19 Newly translated Cherokee cave writings reveal sacred messages
The inscriptions were found in Manitou Cave in Alabama. Shortly before being forced out of their homeland in the 1830s, Cherokee people of the southeastern United States left written accounts on cave walls of secretive rituals. Now researchers have translated some of those messages from long ago. Cherokee inscriptions in Alabama’s Manitou Cave, now a popular tourist destination, describe religious ceremonies and beliefs using written symbols for 85 syllables — enough sounds to replicate the Cherokee spoken language. Cherokee scholar Sequoyah devised this writing system not long before his tribe’s banishment down the Trail of Tears, a series of forced relocations of Native Americans to the west. An historian and a cave photographer first recognized the inscriptions, some of which are written in charcoal, in 2006. A team led by archaeologist Beau Duke Carroll of the Tribal Historic Preservation Office of the Eastern Band of Cherokee Indians in Cherokee, N.C., describes what the writing says in the April Antiquity. One inscription on a wall deep inside the cave, shown above, translates as, “leaders of the stickball team on the 30th day in their month April 1828.” Carroll and his colleagues suspect that the word “their” refers to European Americans. Cherokee stickball was, and still is, a version of lacrosse played between pairs of communities to achieve spiritual renewal. The inscription commemorates a team’s private ritual preparations before a game, the scientists say. A nearby inscription probably refers to the same team’s pregame rituals. That passage identifies the team’s spiritual leader as Richard Guess, the English name of one of Sequoyah’s children.
4-16-19 Stonehenge: DNA reveals origin of builders
The ancestors of the people who built Stonehenge travelled west across the Mediterranean before reaching Britain, a study has shown. Researchers compared DNA extracted from Neolithic human remains found across Britain with that of people alive at the same time in Europe. The Neolithic inhabitants appear to have travelled from Anatolia (modern Turkey) to Iberia before winding their way north. They reached Britain in about 4,000BC. Details have been published in the journal Nature Ecology & Evolution. The migration to Britain was just one part of a general, massive expansion of people out of Anatolia in 6,000BC that introduced farming to Europe. Before that, Europe was populated by small, travelling groups which hunted animals and gathered wild plants and shellfish. One group of early farmers followed the river Danube up into Central Europe, but another group travelled west across the Mediterranean. DNA reveals that Neolithic Britons were largely descended from groups who took the Mediterranean route, either hugging the coast or hopping from island-to-island on boats. Some British groups had a minor amount of ancestry from groups that followed the Danube route. When the researchers analysed the DNA of early British farmers, they found they most closely resembled Neolithic people from Iberia (modern Spain and Portugal). These Iberian farmers were descended from people who had journeyed across the Mediterranean. From Iberia, or somewhere close, the Mediterranean farmers travelled north through France. They might have entered Britain from the west, through Wales or south-west England. Indeed, radiocarbon dates suggest that Neolithic people arrived marginally earlier in the west, but this remains a topic for future work. In addition to farming, the Neolithic migrants to Britain appear to have introduced the tradition of building monuments using large stones known as megaliths. Stonehenge in Wiltshire was part of this tradition. Although Britain was inhabited by groups of "western hunter-gatherers" when the farmers arrived in about 4,000BC, DNA shows that the two groups did not mix very much at all. The British hunter-gatherers were almost completely replaced by the Neolithic farmers, apart from one group in western Scotland, where the Neolithic inhabitants had elevated local ancestry. This could have come down to the farmer groups simply having greater numbers.
4-16-19 Did the ancestor of all humans evolve in Europe not Africa?
THE jaws of an ancient European ape might speak volumes about the origins of our ancestors. A new analysis of these fossils supports a controversial idea: that the apes which gave rise to humans evolved in south-east Europe instead of Africa. Hominins are a group of primates that includes modern humans, extinct humans like Neanderthals and Denisovans, and our immediate ancestors, including australopiths like the famous Lucy. In his 1871 book The Descent of Man, Charles Darwin suggested that the hominin group originated in Africa – an idea most anthropologists believe today. But he also wrote that the group may have arisen in Europe because, at that time, fossils of large apes had already been uncovered there. “Darwin was open-minded,” says David Begun at the University of Toronto, Canada. Almost 150 years later, Begun thinks two fossilised chunks from an upper and lower jaw may support a European origin of hominins. They were found in the 1990s in 8 to 9-million-year-old deposits at Nikiti in northern Greece. Initially assigned to the extinct ape Ouranopithecus, Begun thinks the small yet pointy canines suggest the specimen is a male animal from what may be a previously unknown species. Small canines are a hallmark of hominin species. Begun doesn’t think the Nikiti ape was a hominin, but he thinks it might represent the ancestral group the hominins evolved from, which would suggest the first hominins lived in south-east Europe. Begun outlined the idea at a conference of the American Association of Physical Anthropologists in Cleveland, Ohio, in March. Begun and his colleagues have previously examined fossils of a 7.2-million-year-old ape called Graecopithecus that also once lived in what is now Greece. This animal seemed to have small canines too, plus hominin-like “fused” roots to one of its premolars. In 2017, the team cautiously concluded that Graecopithecus might be a very early hominin. Under this scenario, the 8 to 9-million-year-old Nikiti ape could represent a group of “proto-hominins” that gave rise to hominins in Europe, represented by Graecopithecus at 7.2 million years old. Hominins then migrated into Africa by about 7 million years ago.
4-16-19 Measles has made a shocking return to the US. Can it be stopped?
Insight is your guide to the science and technology that is transforming our world, giving you everything you need to know about the issues that matter most. MEASLES is making a comeback in the US. Public health departments are starting to take serious measures to curb the disease, but in an age of misinformation, simply telling people to get vaccinated may not be enough. New York City is taking drastic action. On 9 April, mayor Bill de Blasio declared a state of emergency in the borough of Brooklyn, and mandated that anyone living in the four zip codes where a measles outbreak has raged since October must be vaccinated or face fines of up to $1000. The unprecedented move was a result of the staggering rise in the number of measles cases, which have mostly been confined to the Orthodox Jewish community in Williamsburg, the mayor said in a press conference. In 2017, there were two cases of measles in New York City. In the past six months, there have been 285. “That’s got our full attention,” said de Blasio, adding that the city will offer free vaccines for those without health insurance. These measures are required because the city is really fighting two epidemics. Measles is fast-spreading and can be deadly. So is the anti-vaccine movement, which has infected the US over the past 20 years, aided by social media platforms and organised misinformation campaigns. There have already been 465 cases of measles in the US this year, according to the Centers for Disease Control and Prevention (CDC). If the disease continues to spread at that rate, there could be more than 1800 cases by the end of the year. (Webmaster's comment: The parents not vaccinating their children against measles are crimnals. They have deliberately endangered everyone including other children with DEATH! Their children should be quarantined and the parents should be imprisioned!)
4-15-19 U.S. measles outbreaks show no signs of slowing down
International travel and hot spots where too few people are vaccinated is fueling the spread. The year has just started, but it’s already a bad one for measles. The viral disease has sickened at least 555 people in 20 states, according to numbers released April 15 by the U.S. Centers for Disease Control and Prevention. That’s more than the 372 cases reported for all of 2018 — and it’s only April. If the outbreak doesn’t get under control, this year could surpass the 2014 high of 667 cases since measles was eliminated from the United States in 2000 (SN Online: 11/30/18). Elimination means that the virus is no longer endemic, or constantly present, though it can still be brought in by overseas travelers. Internationally, outbreaks are ongoing in Ukraine, Israel, the Philippines and Brazil, among other countries. Imported disease is the just the spark. What’s fueling measles outbreaks in the United States are pockets of vulnerability in the country, especially within states that have made it easier for parents to skip vaccinating their children. As public health officials grapple with containing the disease, here’s the lowdown on this not-so-conquered virus. The first signs of an infection include a fever and cough, followed about four days later by a rash of flat, red spots. There’s no treatment for measles, other than managing symptoms with fever reducers, for example. Those who have been exposed to the virus but aren’t immunized can get vaccinated within 72 hours to protect against the illness. Measles can lead to severe medical complications — particularly for babies and young children — including pneumonia or a swelling of the brain that may result in deafness. A decade before the vaccine became available in the United States in 1963, measles sickened around 3 million to 4 million people and killed hundreds each year.
4-15-19 Prescriptions for UTIs may be making antibiotic resistance even worse
WHEN it comes to prescribing antibiotics, doctors are in a jam. Giving them too often risks perpetuating the development of resistance to these drugs in bacteria. That is a serious threat to society. But withholding them is also risky. If the decision is wrong, a patient could develop a life-threatening infection. Even if the doctor is right, this decision often upsets people. I have heard stories of medics being threatened with everything from bad online reviews to physical violence unless they dish the pills. One of the most dangerous areas of medicine in this regard is urinary tract infections. Many fit and healthy people recover from UTIs without antibiotics. But if drugs are needed, they must be administered quickly, or sepsis might set in. That is why doctors often err on the side of caution and give antibiotics for UTIs before they are sure drugs are needed. Previous estimates from the US and Australia suggested that about 30 per cent of antibiotic prescriptions given out for UTIs in hospitals and outpatient settings are inappropriate. Now research presented at a conference by Laura Shallcross of University College London suggests the true figure is much higher: between 60 and 70 per cent. This is based on real test results from patients entering an emergency department in a UK hospital, so there is reason to think the shocking figure is accurate. How do we fix this? The charity I lead, Antibiotic Research UK, aims to help fund the development of one new antibiotic treatment and have it on the market by the early 2020s. But this is a tall order. The pharmaceutical industry isn’t putting enough resources into developing new antibiotics. There isn’t enough profit in them because they are only used for short periods. Governments are also partly to blame. Most haven’t put in place financial incentives to encourage more research by pharmaceutical firms.
4-15-19 A touch-feely part of the brain helps you enjoy a gentle caress
A part of the brain called the insular cortex appears to be behind why a tender stroke can feel so nice. Parts of the skin that have hairs on them, such as the backs of hands but not the palms, have nerve fibres, which respond to gentle touch. Normally when mammals are touched, these fibres send a signal through the spinal cord to the part of the brain called the primary somatosensory cortex, which responds to changes on the surface of the body. But for pleasurable touch, this signal takes a detour to the insular cortex first, which is involved in self-awareness. To understand how these pleasure signals are processed, Louise Kirsch at Sorbonne University in France and her colleagues compared touch responses of 59 people who had strokes with 20 healthy people. The team gently touched the participants with a soft-bristled brush on their right and left forearms at two speeds – the slower of the two is known to stimulate the pleasure-sensing nerve fibres. They asked everyone to rate how intensely they felt the touch and how pleasant it was on a scale of 0 to 10, where 0 was the feeling of sandpaper and 10 was the feeling of velvet. All the participants found the slower brush stroke speed more pleasurable, but some of those who had experienced a stroke rated it less so than the healthy control group. When the team analysed the brain scans of the participants, they found that over 80 per cent of people who’d had a stroke and reported less sensitivity to pleasant touch on their arm had a lesion on the their insular cortex, suggesting that the disruption in enjoying pleasurable touch is tied to this part of the brain.
4-15-19 Some people may have genes that hamper a drug’s HIV protection
Newly discovered genetic variants could explain why a common medication doesn’t protect all. Some people’s genes may stop an antiretroviral drug from protecting them against HIV, a genetics study suggests. The drug, called tenofovir, is used for preventing as well as treating an HIV infection. But success in prevention has been mixed, with studies reporting between 78 to 92 percent success rates. It wasn’t clear why the drug didn’t protect everyone. Now, studies reveal that rare genetic variants can prevent tenofovir from becoming active in the body, pharmacologist Namandjé Bumpus of Johns Hopkins University School of Medicine reported April 8 at the 2019 Experimental Biology meeting. People who have HIV or who are at risk of contracting HIV, such as someone whose partner has the virus, take an inactive form of the drug that must be activated in the body in a two-step process. Scientists knew enzymes called kinases are required, but weren’t sure which of the many kinases in the human body convert the drug to its active form. An enzyme called adenylate kinase 2 attaches one phosphate atom and another enzyme, creatine kinase, tacks on a second to spur the drug to action, Bumpus and colleagues discovered. Variants of the kinases are rare: Only 18 adenylate kinase 2 variants were found among 906 people whose DNA was tested. Separately, the researchers tested whether the variants affected the ability of adenylate kinases to activate tenofovir. Of 477 people taking the drug, seven people with variants predicted to disable the enzyme didn’t have the active version of tenofovir in their blood. That result hints that the variants do affect the drug’s effectiveness.
4-14-19 The benefit of learning the arts as a kid
Studies show that learning music, theater, or art can boost kids' learning capabilities. Does your middle schooler want to study music, theater, or dance? Do you fear it will be a distraction from academics and put their grades at risk? A rigorously designed, decade-long study of more than 30,000 Florida students suggests the exact opposite is more likely. It found students who took an elective arts class in sixth, seventh, or eighth grade had significantly higher grade point averages (GPAs), and better scores on standardized reading and math tests, than their peers who were not exposed to the arts. This held true after the researchers took into account "all the ways that students who did and did not take the arts in middle school were initially different." While much research has suggested music and arts training confers academic benefits, the chicken-and-egg question has made definitive declarations difficult. At least one major study concluded music students do better at school largely because smarter, more capable kids are more likely to choose to study music. The new study, in the journal Psychology of Aesthetics, Creativity, and the Arts, addresses that issue by following a large group of low-income students from kindergarten through eighth grade. This allowed the researchers to create a baseline level of each youngster's academic accomplishments, and determine if arts classes boosted their achievement level. The short answer is they did. The research team, led by George Mason University psychologist Adam Winsler, focused on middle school, reasoning it is both a key period for brain development and "the first time students can choose to take full elective arts courses, and they can still enroll in these arts-related classes with limited skills." Using data from the Miami School Readiness Project, the researchers tracked the progress of 31,322 ethnically diverse, primarily low-income students. They noted each child's level of school readiness at age four, including cognitive, language, and social skills, as well as their scores on standardized math and reading tests in fifth grade.
4-13-19 Gene-silencing: 'New class' of medicine reverses disease porphyria
Doctors have used a new type of medicine called "gene silencing" to reverse a disease that leaves people in crippling pain. The condition, acute intermittent porphyria, also causes paralysis and is fatal in some cases. The novel approach fine-tunes the genetic instructions locked in our DNA. Doctors say they are "genuinely surprised" how successful it is and that the same approach could be used in previously untreatable diseases. Sue Burrell, from Norfolk, has endured pain few could imagine and needed to take strong opioid painkillers every day. At one point her porphyria was causing severe attacks every couple of weeks and needed hospital treatment. But even then morphine did not stop the pain. She told the BBC it was worse than child-birth, saying: "It's so intense - so strong it's in your legs, in your back, and it just resonates everywhere. It's really, really unbearable." Her sister was affected even more severely and was completely paralysed in hospital for two years. There are several types of porphyria, but each is caused by the body being unable to produce enough of a substance called haem. Haem is a key component of the haemoglobin in red blood cells that transport oxygen around the body. Problems in the body's haem manufacturing process can lead to a build up of toxic proteins. These cause the attacks of physical pain in Sue's form of the disease. In other porphyrias the proteins can cause skin problems. Sue was one of the patients on the trial and is now taking the drug. She says her life has been transformed. "I've had pain for 10 years, I didn't expect that could go away. I'm seeing friends and they're [asking] 'you're not taking any painkillers?' and I was [saying] 'no!'." A clinical trial on 94 people across 18 countries was presented at the International Liver Congress in Vienna.
4-12-19 Immunization emergency
With 285 confirmed cases of measles since a citywide outbreak began last fall, Mayor Bill de Blasio declared a public health emergency. Saying it’s “time to take a more muscular approach,” he threatened fines of $1,000 for people in affected neighborhoods who fail to vaccinate their kids. The outbreak is concentrated among ultra-Orthodox Jewish children in Williamsburg, Brooklyn. After a ban preventing unvaccinated students from attending schools there proved ineffective, de Blasio said the city could temporarily shut down yeshivas that defy city guidelines. Rabbis largely endorse vaccinations, though a pamphlet has circulated in Williamsburg claiming the measles vaccine “kills more kids than the disease would.” The New York Civil Liberties Union called de Blasio’s “forced vaccination” illegal, and last week a judge in nearby Rockland County struck down an order barring unvaccinated children from public places.
4-12-19 IVF and childhood cancer
New research suggests that some rare childhood cancers are more common in children conceived through in vitro fertilization—though the overall risk remains extremely low. Researchers from the University of Minnesota compared nearly 276,000 children conceived via IVF in the U.S. from 2004 to 2013 with 2.3 million kids conceived naturally during the same period. They found that the IVF children were 17 percent more likely to develop childhood cancer, largely because they were more than twice as likely to have liver tumors. While the study was observational, and so didn’t prove causation, the authors suggest the increased risk could be linked to the advanced average age of parents who try IVF or to underlying issues linked to their infertility. But lead author Logan Spector tells Reuters.com that the few cancers associated with the increased risk are “extremely rare,” and that there’s nothing patients or providers “should be doing differently.”
4-12-19 The day the dinosaurs died
Paleontologists have discovered an extraordinary trove of fossils that appears to capture the moments after an asteroid slammed into Earth some 66 million years ago, dooming the dinosaurs to extinction. When the 7.5-mile-wide asteroid smashed into what is now the Gulf of Mexico, it ripped a hole in Earth’s crust some 50 miles wide and 18 miles deep. Mega-earthquakes and colossal tsunamis rippled out from the impact site, and billions of tons of molten rock was hurled into the sky and across thousands of miles. That debris fell back to Earth as tiny globs of glass known as tektites, reports NationalGeographic.com, in a pulverizing rain that lasted for 45 minutes. The new excavation site, near Bowman, N.D., is full of fossils of sea creatures that were swept inland by giant waves, tangled together with a mass of trees, flowers, and land-inhabiting vertebrates. The gills of fish at the site are clogged with tektites. The cataclysm “essentially stockpiled the rarest and most poorly represented things in [the rock formation] in one deposit that we can study for decades,” said Robert DePalma, the paleontologist who found the fossil bed. He says the site also contains dinosaur fossils, which he will examine in further studies.
4-12-19 96 bags of human waste
Astronauts from NASA’s six Apollo moon missions left 96 bags of human waste on the moon. If a future moon mission discovers that any of the microorganisms in that waste were able to survive the intense temperatures and bombardment of radiation on the lunar surface, it might indicate that hardy microbes can spread life throughout the universe.
4-12-19 How chemical exposure early in life is ‘like a ticking time bomb’
Diet as an adult determined whether mouse pups exposed to BPA developed health problems. Being exposed to a chemical early in life can be a bit like a choose-your-own-adventure book: Some things that happen early on may hurt you later, but only if you make certain choices, an unpublished study in mice suggests. Mouse pups were exposed to the chemical bisphenol A (BPA) for only five days after birth, a crucial time during which mice’s livers develop. BPA, once common in plastics, has been linked to a host of health problems in people, from diabetes to heart disease (SN: 10/11/08, p. 14). But depending on diet as adults, the mice either grew up to be healthy or to have enlarged livers and high cholesterol. As long as the BPA-exposed mice ate mouse chow for the rest of their lives, the rodents remained healthy, molecular biologist Cheryl Walker of Baylor College of Medicine in Houston reported April 7 at the 2019 Experimental Biology meeting. But researchers switched some BPA-exposed mice to a high-fat diet as adults. Those mice had larger livers, higher cholesterol and more metabolic problems than mice who ate a high-fat diet but were not exposed to BPA as pups, Walker said. BPA exposure immediately altered epigenetic marks at more than 5,400 genes, including 3,000 involved in aging. Epigenetic marks are chemical tags on DNA or on histones — protein around which DNA winds in a cell — that don’t change information in genes themselves, but affect gene activity. Some genes with histone epigenetic marks that were reprogrammed early in life are like “ticking time bombs that remain silent until a later life challenge,” Walker said. For instance, BPA altered histone marks on the EGR1 gene in mouse pups, but activity of the gene didn’t change unless mice ate a high-fat diet as adults. That gene helps control metabolism.
4-11-19 Ketamine cultivates new nerve cell connections in mice
Helping the regrowth of synapses may be the key to the drug’s antidepressant effects. Ketamine banishes depression by slowly coaxing nerve cells to sprout new connections, a study of mice suggests. The finding, published in the April 12 Science, may help explain how the hallucinogenic anesthetic can ease some people’s severe depression. The results are timely, coming on the heels of the U.S. Food and Drug Administration’s March 5 approval of a nasal spray containing a form of ketamine called esketamine for hard-to-treat depression (SN Online: 3/21/19). But lots of questions remain about the drug. “There is still a lot of mystery in terms of how ketamine works in the brain,” says neuroscientist Alex Kwan of Yale University. The new study adds strong evidence that newly created nerve cell connections are involved in ketamine’s antidepressant effects, he says. While typical antidepressants can take weeks to begin working, ketamine can make people feel better in hours. Scientists led by neuroscientist Conor Liston suspected that ketamine might quickly be remodeling the brain by spurring new nerve cell connections called synapses. “As it turned out, that wasn’t true, not in the way we expected, anyway,” says Liston, of Cornell University. Newly created synapses aren’t involved in ketamine’s immediate effects on behavior, the researchers found. But the nerve cell connections do appear to help sustain the drug’s antidepressant benefits over the longer term. To approximate depression in people, researchers studied mice that had been stressed for weeks, either by being restrained daily in mesh tubes, or by receiving injections of the stress hormone corticosterone. These mice began showing signs of despair, such as losing their taste for sweet water and giving up a struggle when dangled by their tails.
4-12-19 Why some low-income neighborhoods are better than others
Exposure to lead, violence and incarceration affects kids’ upward mobility. Chicago’s mayor-elect Lori Lightfoot pledged in her victory speech on April 2 to “make Chicago a place where your zip code doesn’t determine your destiny.” But turning that pledge into reality will require addressing more than poverty, according to a study that followed the lives of thousands of children in the city. Kids from low-income neighborhoods that are beset by high rates of violence, incarceration and lead exposure earn less money, on average, in adulthood than equally poor children from less hazardous neighborhoods, researchers found. Children from these grittier neighborhoods are also more likely to become pregnant as teenagers or to be jailed in their 20s or 30s as children from less “toxic” communities, the team reports April 1 in the Proceedings of the National Academy of Sciences. “One thing that’s particularly painful about poverty right now is you’re getting hit from all these different angles,” from higher local crime and violence statistics to more environmental contaminants like lead, says study coauthor Robert Manduca, a sociologist at Harvard University. Both black and white children who grew up in these toxic communities suffered the long-term effects. But, citywide, black children were more exposed to the hazards than white. Chicago’s neighborhoods remain largely segregated, and predominately black neighborhoods tend to have higher crime and pollution levels, on average, than white neighborhoods, the team says. In particular, the new results show that if a black boy had grown up with the lower hazards present in a poor white neighborhood, his odds of being jailed by the time he reached adulthood would have dropped from about 12 to 6 percent. And his income in his 30s would have been about $4,200 higher, the team reports. A black girl’s likelihood of teen pregnancy would likewise drop, from 54 to 44 percent.
4-11-19 What happened when one twin went to space and the other stayed home?
NASA astronaut Scott Kelly spent a year in space and came back a slightly changed man – at least, in comparison to his twin brother Mark, who was earthbound while Scott was aboard the International Space Station. This experiment, conducted from March 2015 to March 2016, will help us plan for astronauts to travel for years to Mars or beyond. Scott and Mark (himself a former astronaut) both gave NASA scientists samples of their blood, urine and faeces before, during and after the year-long flight – Scott’s samples were ferried back to Earth in Soyuz capsules returning other astronauts from the ISS. Scott’s DNA saw some changes, compared to his twin. His telomeres – the endcaps of chromosomes that usually shorten as we age – lengthened over the 340 days he spent in space. This could be due to exposure to space radiation, according to the NASA team that released these results. Within 2 days of returning to Earth, his telomeres rapidly shortened and returned to their pre-flight length within months. One big difference between the twins was seen in their urine. Their metabolites – the products of metabolic processes – were similar in their blood plasma, but 32 urinary metabolites were significantly altered during spaceflight. On the other hand, their faecal samples retained similar microbial communities – both dominated by bacteria from the Firmicutes and Bacteroidetes phyla. Mark’s faecal microbiome varied more than Scott’s from pre- to post-flight, but the changes were not significant. NASA also found that Scott’s immune system responded similarly to Mark’s when given a flu vaccine, suggesting that immunisations in space should work as we expect, if they are needed in the future. We’re only just beginning to understand the long-term effects of living in low gravity and exposure to space radiation, and while this study helps further our knowledge, it’s based on just one astronaut.
4-11-19 NASA’s Twins Study reveals effects of space on Scott Kelly’s health
A comparison with his twin looks at the impact of long-term spaceflight on the human body. For nearly a year, U.S. astronauts and identical twins Scott and Mark Kelly lived lives that were as separate as Earth and space — literally. While Mark enjoyed retirement in Tucson, his brother floated in microgravity aboard the International Space Station orbiting about 400 kilometers above the planet. Ten science teams studied the twins’ physiology, memory abilities and genes before, during and after that year, looking for any deviations that might suggest Scott’s 340 days in space affected him physically. While researchers have dropped tantalizing hints about what NASA’s Twins Study found, now a comprehensive study published in the April 12 Science confirms that lengthy space travel triggers stressors that can manipulate genes, send the immune system into overdrive or impair mental reasoning abilities and memory. Whether these stressors have long-term health repercussions is still unclear. This is “the most comprehensive view that we’ve ever had of the response of the human body to spaceflight,” says Susan Bailey, a radiation cancer biologist at Colorado State University in Fort Collins who led one of the research teams. Within the first few days after Scott entered space in March 2015, he took blood samples that were sent back to Earth. Tests revealed epigenetic tags on more than 1,000 of his genes that weren’t in his preflight samples or samples from Mark. These chemical markers, which can turn a gene on or off when added or removed, can be caused by environmental factors and are reversible. Most affected were genes regulating the repair of DNA and the length of telomeres, the tips of chromosomes, Bailey’s team found.
4-11-19 A gene linked to alcohol habits may influence who you choose to marry
Should you go on that second date? A gene that influences how much alcohol we drink may also shape our decisions when choosing a partner. It’s no secret that many couples have similar patterns when it comes to alcohol use, but pinning down the underlying reason has been tricky. One explanation could be that a couple’s drinking habits become more alike over time. Laurence Howe at the University of Bristol says previous studies on the link between alcohol use and partner choice have relied mostly on self-reported data. “We wanted to disentangle the possibilities using a genetic approach,” he says. Howe and his team analysed the genetic data of 47,000 couples in the UK Biobank and compared this with each person’s reported alcohol consumption. In particular, they were interested in a variant of the ADH1B gene, which is known to be associated with heavier drinking. They found that regular drinkers were more likely to pair up with similar drinkers, and that each person in such a pair was more likely to have this gene variant. People who didn’t drink very often tended to form relationships with other light drinkers, and both partners in such a couple were more likely to have a different variant of the same gene – one that is associated with experiencing unpleasant alcohol side effects. “This suggests that alcohol consumption directly influences mate choice, adding to the growing evidence that humans are more likely to select a similar mate,” says Howe. “Our genotypes cannot be changed by our partner’s habits.” However, the study did suggest a person’s partner can have a small influence on their drinking habits. Each unit increase in a partner’s weekly alcohol intake was linked to an average 0.26 unit increase in their significant other’s weekly consumption.
4-11-19 First 3-parent baby born in clinical trial to treat infertility
A Greek woman has given birth to a baby boy using a controversial technique that combines DNA from three people, in the first clinical trial of its kind to treat infertility. The boy was born on 9 April, to a 32-year-old woman with a history of multiple IVF failures and poor egg quality. Both the mother and the baby are in good health, announced researchers at The Institute of Life, in Athens, Greece, where the procedure was performed. The team claim they are making medical history, but several researchers have expressed concern over the use of the technique for infertility, as this is not what it is originally developed for. Instead it was meant as a way for mothers to avoid passing on mitochondrial disease to their children. The technique is called spindle nuclear transfer, in which the nucleus from the mother is transferred into a donor egg that has had its nucleus removed. The donor egg is then fertilised with sperm from the father and returned to the mother. The resulting child would possess genetic material from the mother and the father and a small number of genes from the donor. The first child created using this technique was born in 2016 in Mexico, a little boy, whose mother carried genes for Leigh syndrome, a fatal neurological disorder linked to genes in mitochondria. In the Athens trial, the woman who gave birth did not have mitochondrial problems, says Gloria Calderon at Spanish company Embryotools, which was involved with the trial. “She has fertility problems related with poor egg quality and had four failed IVF attempts due to poor embryo development,” says Calderon. The trial’s official clinical record states that it aims to recruit 25 women under 40, who have been diagnosed with infertility due to poor egg quality, who have had at least two failed IVF attempts.
4-11-19 ‘Three-person’ baby boy born in Greece
Fertility doctors in Greece and Spain say they have produced a baby from three people in order to overcome a woman's infertility. The baby boy was born weighing 2.9kg (6lbs) on Tuesday. The mother and child are said to be in good health. The doctors say they are "making medical history" which could help infertile couples around the world. But some experts in the UK say the procedure raises ethical questions and should not have taken place. (Webmaster's comment: It wasn't in Gods plan. What a bunch of Crap!)The experimental form of IVF uses an egg from the mother, sperm from the father, and another egg from a donor woman. It was developed to help families affected by deadly mitochondrial diseases which are passed down from mother to baby. It has been tried in only one such case - a family from Jordan - and that provoked much controversy. But some fertility doctors believe the technology could increase the odds of IVF too. This is all about mitochondria - they are the tiny compartments inside nearly every cell of the body that convert food into useable energy. They are defective in mitochondrial diseases so combining the mother's DNA with a donor's mitochondria could prevent disease. But there is also speculation mitochondria may have a role in a successful pregnancy too. That claim has not been tested. The patient was a 32-year-old woman in Greece who had endured four unsuccessful cycles of IVF. She is now a mother, but her son has a tiny amount of his genetic makeup from the donor woman as mitochondria have their own DNA.
4-11-19 Pollinators may have evolved 40 million years before flowers existed
Many flowers make nectar to attract visits from pollinating insects – a classic example of a mutually beneficial relationship refined by millions of years of evolution. But a reanalysis of a Jurassic fly suggests pollinators may have been flying around on Earth long before the first flowers bloomed. Alexander Khramov, of the Borissiak Palaeontological Institute in Moscow, Russia, and his colleagues have been studying a specimen of Archocyrtus kovalevi, a late Jurassic fly first described in 1996. When the team zoomed in on a long, straight structure lying underneath the fly’s compressed body with microscopes, they realised it wasn’t a piece of vegetation, as previously assumed, but rather a part of the fly. The structure isn’t enriched in carbon, as would be expected for vegetation, and a food canal running through its middle is clearly visible. They report that A. kovalevi was about a centimeter long with a large, drinking straw-like proboscis nearly twice its body-length. As it doesn’t have any piercing structures, the team think the proboscis was for sucking nectar, not blood. But at about 160 million years old, the fly is over 40 million years older than the emergence of the angiosperms, the group of flowering plants. “Finding a fossil insect of that age with such a wonderfully long proboscis is like finding a caveman with an AK-47,” says Khramov. Since A. kovalevi lived in a flowerless world, Khramov thinks the fly’s giant straw was for reaching into the cones of gymnosperms, the group of plants that includes conifers. One candidate is Bennettiales, a now-extinct type of plant with almost flower-like cones that may have lured pollinators with hidden sugar drops. The fly’s proboscis is about the right length for the job, and fossils of these plants’ cones were found in the same layer of rock.
4-10-19 'Dismantling cancer' reveals weak spots
Scientists have taken cancer apart piece-by-piece to reveal its weaknesses, and come up with new ideas for treatment. A team at the Wellcome Sanger Institute disabled every genetic instruction, one at a time, inside 30 types of cancer. It has thrown up 600 new cancer vulnerabilities and each could be the target of a drug. Cancer Research UK praised the sheer scale of the study. The study heralds the future of personalised cancer medicine. At the moment drugs like chemotherapy cause damage throughout the body. One of the researchers is Dr Fiona Behan, whose mother died after getting cancer for the second time. The first course of chemotherapy damaged her mother's heart, so she was not physically strong enough for many treatments the second time around. Dr Behan told the BBC: "This is so important because currently we treat cancer by treating the entire patient's body. We don't target the cancer cells specifically. "The information we have uncovered in this study has identified key weak-spots of the cancer cells, and will allow us to develop drugs that target the cancer and leave the healthy tissue undamaged." Cancer is caused by mutations inside our body's own cells that change the instructions written into our DNA. Mutations corrupt cells leading to them growing uncontrollably, spreading around the body and eventually killing people. The researchers embarked on a gargantuan feat of disabling each genetic instruction - called a gene - inside cancers, to see which were crucial for survival. They disrupted nearly 20,000 genes in more than 300 lab-grown tumours made from 30 different types of cancer. They used a tool called Crispr - the same genetic technology that was used to re-engineer two babies in China last year. It is a relatively new, easy and cheap tool for manipulating DNA, and this study would have been an impossible feat just a decade ago. The results, published in the journal Nature, revealed 6,000 crucial genes which at least one type of cancer needs to survive. Some were unsuitable for developing cancer drugs, as they are also essential in healthy cells. Others are already the target of precision drugs like Herceptin in breast cancer - the team called this a "sanity check" that proves their method works. And yet more are beyond current science to develop suitable drugs, so the researchers narrowed down a shortlist of 600 potential new targets for drugs to attack.
4-10-19 Medicare for All: Can Bernie Sanders overhaul US healthcare?
Democratic presidential hopeful Bernie Sanders is unveiling his vision for a national health care plan that is expected to be adopted by several other leading White House candidates. So what is it? It's widely known that the US has the most expensive healthcare system in the world, and health outcomes vary according to your means. President Barack Obama tried to overhaul it. But even after his landmark Affordable Care Act, some 27 million Americans remain uninsured. His successor in the White House has tried to dismantle that legislation, making healthcare a central issue in next year's presidential election. Senator Sanders' plan - called Medicare for All - will play a big part in the debate. So what's in it? Medicare for All is a proposal to expand Medicare into a single-payer health system. That means the federal government would be the sole, nationwide insurance provider for all essential and preventative healthcare. It is not a universal health care system where the government would own and operate hospitals - instead, the government would pay private providers an agreed upon rate for their services. Under Senator Bernie Sanders' proposal, first introduced in 2017 and re-introduced in April, Medicare for All would expand Medicare's coverage to include vision, dental, prescription drugs, nursing home care and reproductive health services. The 2019 update to the plan also includes a long-term care coverage for patients with disabilities - amending one of the criticisms of his earlier plan. The change also brings Mr Sanders' plan more in line with the version of Medicare for All proposed in the House of Representatives by congresswoman Pramila Jayapal of Washington state. In four years, Mr Sanders' plan would have the country phase out of private insurance plans so everyone would receive insurance from the federal government. The Affordable Care Act would also end, as users would be enveloped into the national plan. Private insurance companies and employers would be banned from selling any manner of duplicate plans for services covered under the government's programme, though plans for non-essential medical services like cosmetic surgery could remain. Mr Sanders' proposal would see an end to the "cost sharing" that makes up the current system: No deductibles, no premiums, no co-payments for care. The only out-of-pocket expense under Mr Sanders' plan would be for some non-generic prescription drugs, but any cost to the patient would be capped at $200 annually. For comparison, US patients in 2016 paid over $535bn for prescription drugs, according to government estimates. (Webmaster's comment: Why is American Healthcare so expensive? Because it's a for profit system, healthcare is a secondary objective!)
4-10-19 New species of human discovered in a cave in the Philippines
IN CALLAO cave on the island of Luzon in the Philippines, history may be repeating itself. About 16 years ago, archaeologists working on the relatively nearby island of Flores discovered the remains of a previously unknown ancient human species. Now a different team says Luzon was once home to a mysterious human species that it has named Homo luzonensis. The discovery raises an obvious question: did further human species evolve on other islands in the region? The first signs of ancient humans on Luzon came in 2007, when a team co-led by Florent Détroit at the French National Museum of Natural History and Armand Salvador Mijares at the University of the Philippines discovered a 67,000-year-old human foot bone. They tentatively assigned it to our species, but by 2016 there were rumours that Détroit and Mijares had found more fossils and that they looked too primitive to belong to Homo sapiens. Now we have confirmation. The team has found 12 more fossils: seven teeth, two finger bones, two toe bones and part of a thigh bone. Some of the teeth have been dated as 50,000 years old. This means the fossils are roughly the same age as some of the “hobbit” human remains found about 3000 kilometres to the south on Flores in 2003. But the Luzon fossils have distinct features and so belong to a different species, according to Détroit and Mijares. Détroit says it isn’t yet possible to know whether this species was small in stature like the Homo floresiensis hobbits because there are so few fossils. But William Jungers at Stony Brook University in New York says that the teeth are extraordinarily small, “even in comparison to small-bodied populations of modern humans from the Philippines”.
4-10-19 A new hominid species has been found in a Philippine cave, fossils suggest
The newly dubbed Homo luzonensis lived at least 50,000 years ago, scientists say. A new member of the human genus has been found in a cave in the Philippines, researchers report. Fossils with distinctive features indicate that the hominid species inhabited the island now known as Luzon at least 50,000 years ago, according to a study in the April 11 Nature. That species, which the scientists have dubbed Homo luzonensis, lived at the same time that controversial half-sized hominids named Homo floresiensis and nicknamed hobbits were roaming an Indonesian island to the south called Flores (SN: 7/9/16, p. 6). In shape and size, some of the fossils match those of corresponding bones from other Homo species. “But if you take the whole combination of features for H. luzonensis, no other Homo species is similar,” says study coauthor and paleoanthropologist Florent Détroit of the French National Museum of Natural History in Paris. If the find holds up to further scientific scrutiny, it would add to recent fossil and DNA evidence indicating that several Homo lineages already occupied East Asia and Southeast Asian islands by the time Homo sapiens reached what's now southern China between 80,000 and 120,000 years ago (SN: 11/14/15, p. 15). The result: an increasingly complicated picture of hominid evolution in Asia. Excavations in 2007, 2011 and 2015 at Luzon’s Callao Cave yielded a dozen H. luzonensis fossils at first — seven isolated teeth (five from the same individual), two finger bones, two toe bones and an upper leg bone missing its ends, the scientists say. Analysis of the radioactive decay of uranium in one tooth suggested a minimum age of 50,000 years. Based on those fossils, a hominid foot bone found in 2007 in the same cave sediment was also identified as H. luzonensis. It dates to at least 67,000 years ago.
4-10-19 Homo luzonensis: New human species found in Philippines
There's a new addition to the family tree: an extinct species of human that's been found in the Philippines.It's known as Homo luzonensis, after the site of its discovery on the country's largest island Luzon. Its physical features are a mixture of those found in very ancient human ancestors and in more recent people. That could mean primitive human relatives left Africa and made it all the way to South-East Asia, something not previously thought possible. The find shows that human evolution in the region may have been a highly complicated affair, with three or more human species in the region at around the time our ancestors arrive. One of these species was the diminutive "Hobbit" - Homo floresiensis - which survived on the Indonesian island of Flores until 50,000 years ago. Prof Chris Stringer, from London's Natural History Museum, commented: "After the remarkable finds of the diminutive Homo floresiensis were published in 2004, I said that the experiment in human evolution conducted on Flores could have been repeated on many of the other islands in the region." That speculation has seemingly been confirmed on the island of Luzon... nearly 3,000km away." (Webmaster's comment: Another missing link in the human evolutionary tree.)
4-10-19 We contain microbes so deeply weird they alter the very tree of life
Newly discovered life forms inside our bodies profoundly affect our health – and provide a glimpse of the vast and mysterious biological "dark matter" within us. ERIC BAPTESTE is on a hunt for life, but not as we know it. He doesn’t think we have to sift through Martian soils or trawl lunar oceans to find these entities. His hunting ground is far closer to home: the human body. “Biology is full of surprises,” says Bapteste, an evolutionary biologist at the Pierre and Marie Curie University in Paris. “Since we have not yet exhaustively sampled all the DNA in the world, there is still room for finding rare, strange creatures.” A realist might say that Bapteste’s mission is doomed to fail. After all, we are in the 2010s, not the 1710s. It is unthinkable that biologists can unearth new divisions of life on Earth – let alone make those discoveries in the intimately familiar environment of the human body. They would be wrong. Recent research shows that our bodies are home to microbes unlike anything science has encountered before – some so alien that they are rewriting the tree of life. What’s more, this microbial “dark matter” could be having a profound effect on our health, for better and worse. The body is home to some 39 trillion microbes, which outnumber our 30 trillion human cells. Our skin has a billion bacteria per square centimetre. Earlier this year, a study found that as many as 2000 different species can thrive in the human gut – although a smaller subset of these live in or on any one individual. For years we assumed these microbes were harmful, but we now know that many of them are actually our allies, closely linked with our health and well-being (see “The human zoo”). Thanks to new technology, we can now study them in unprecedented detail.
4-10-19 The world's largest stone circle started out as a humble ancient home
AVEBURY henge contains the world’s largest stone circle, but unlike its more famous neighbour Stonehenge, we know little about it. Now buried structures have been found at the monument that suggest the ancient complex began as a simple dwelling. The monument in Wiltshire, UK, is just 30 kilometres from Stonehenge. It comprises a 332-metre-wide stone circle, containing two further stone circles and avenues of paired standing stones. The entire site is surrounded by a circular ditch and embankment. But Avebury’s origins have been uncertain, as it hasn’t been investigated to the same extent as Stonehenge. The last major excavation took place in the 1930s, and couldn’t determine whether Avebury was constructed gradually over time, or as one large entity. To investigate, Mark Gillings at the University of Leicester, UK, and his colleagues used ground-penetrating radar to look for buried structures, as well as re-examining records of earlier investigations. The team focused on the southern inner stone circle, which is 100 metres wide. The radar survey found a square of standing stones buried in the middle of the circle, with sides 30 metres long. “To find a square megalithic structure is very unusual,” says team member Joshua Pollard of the University of Southampton, UK. The square was built around another structure, which appears to be the remains of a Neolithic house, in the geometric centre of the southern inner stone circle. This leads the team to believe that the monument started out as a house in the early Neolithic era. Flint tools at the site and the age of similar dwellings elsewhere suggest this was around 3700 BC.
4-9-19 Salmonella can hijack immune cells to spread around the body
Salmonella can hijack immune cells and use them to spread around the body. Experiments in mouse cells suggest that the bacteria causing the infection do this by disrupting electrical signals in the gut. Our intestines have small electric fields, caused by charged ions, such as potassium and chloride, flowing in and out of intestinal cells. Salmonella infections, which can feature food poisoning, disrupt these electric fields because they damage the cells, which alerts the body’s immune cells to come and clean up the mess. Usually, the immune system is good at limiting the infection to the gut. But sometimes the bacteria that cause salmonella escape by riding inside macrophages, a type of immune cell that doesn’t normally leave the gut, to other organs like the liver and spleen. To investigate the process, Yaohui Sun at the University of California, Davis, and his colleagues placed gut membrane cells from mice in an electric field to mimic an infected gut. The team found that without the presence of the bacteria, nearly all macrophages moved towards the positively charged end of the field, corresponding to the interior of the intestines. However, after engulfing Salmonella enteritidis, the most common species associated with food poisoning, about 41 per cent of macrophages reversed direction, moving towards the negatively charged end, corresponding to leaving of the gut. We knew that the Salmonella bacteria have proteins that help them survive within macrophages, but it is unclear how they flip the electric charge the macrophages are attracted to, says Sun. It is possible that bacteria release enzymes that damage the charge-sensing sugar structures on the macrophages’ surface, he says.
4-9-19 Promising treatment for chronic fatigue syndrome fails large trial
A medicine that people hoped would treat chronic fatigue syndrome (CFS) has failed its first large placebo-controlled trial. The drug, called rituximab, is used to treat cancer and autoimmune diseases in which the immune system makes antibodies that turn against the body. The medicine works by killing the cells that make antibodies. A few people who had cancer and also happened to have CFS saw their symptoms of fatigue resolve after taking rituximab. Øystein Fluge of Haukeland University Hospital in Norway thought rogue antibodies could be involved in CFS, also known as myalgic encephalomyelitis (ME). These initial findings were borne out by some small studies. Fluge and his colleagues’ latest trial was larger, involving 151 people. Half had regular infusions of rituximab for a year, while the rest got placebo infusions. Their symptoms were measured over this time and for a further year, as the drug can take several months to work. About 25 per cent of people in the treatment group saw their tiredness alleviate – but so did 35 per cent of people in the placebo group. Rituximab also caused a higher rate of side effects that required going to hospital, such as infections. Fluge says the first people who got better after taking rituximab may have done so because of the placebo effect, or because their condition naturally resolved. Alternatively, they could have been different in some way from other people with CFS. The results are a blow to the idea that antibodies cause CFS, says Fluge, “but it doesn’t exclude that other parts of the immune system are active in this disease”.
4-9-19 Chickens stand sentinel against mosquito-borne disease in Florida
Antibodies in the birds reveal when certain viral pathogens are being transmitted locally. For 40 years, they’ve held the front line in Florida’s fight against mosquito-borne diseases. And it turns out that the chickens standing sentinel in cities, marshes, woodlands and residential backyards are clucking good at their job. Last year, chickens in 268 coops in over a third of Florida’s counties provided scientists weekly blood samples that revealed whether the birds had been bitten by mosquitoes carrying West Nile virus or the Eastern equine encephalitis or St. Louis encephalitis viruses. If a chicken’s blood tests positive for antibodies to one of those viruses, authorities know that the pathogen is circulating. And if enough birds have the antibodies, state officials can ratchet up mosquito-killing measures such as pesticide spraying to help halt disease spread. The sentinel chicken surveillance programs are “a really good way of monitoring” for certain virus activity, says Thomas Unnasch, a biologist who studies vector-borne diseases at the University of South Florida in Tampa. The birds “are sampling literally hundreds or thousands of mosquitoes every day,” he says. (The chickens can’t keep tabs on dengue or Zika; the mosquitoes carrying those viruses prefer to bite people rather than birds.) In 2018, 833 chickens tested positive for West Nile virus antibodies in Florida, but only 39 people did, according to data from the state’s health department. For Eastern equine encephalitis virus, 154 chickens tested positive in 2018, compared with only three people. Chickens that test positive for the viruses being surveyed don’t transmit them, and people don’t either. Both are considered “dead-end hosts,” meaning that the viral concentration in the blood doesn’t get high enough to infect another mosquito after it bites.
4-9-19 Our brains sculpt each other. So why do we study them in isolation?
Minds may best be understood as they exist, in social settings Brains have long been star subjects for neuroscientists. But the typical “brain in a jar” experiments that focus on one subject in isolation may be missing a huge part of what makes us human — our social ties. “There’s this assumption that we can understand how the mind works by just looking at individual minds, and not looking at them in interactions,” says social neuroscientist Thalia Wheatley of Dartmouth College. “I think that’s wrong.” To answer some of the thorniest questions about the human brain, scientists will have to study the mind as it actually exists: steeped in social connections that involve rich interplay among family, friends and strangers, Wheatley argues. To illustrate her point, she asked the audience at a symposium in San Francisco on March 26, during the annual meeting of the Cognitive Neuroscience Society, how many had talked to another person that morning. Nearly everybody in the crowd of about 100 raised a hand. Everyday social interactions may seem inconsequential. But recent work on those who have been isolated, such as elderly people and prisoners in solitary confinement, suggests otherwise: Brains deprived of social interaction stop working well (SN: 12/8/18, p. 11). “That’s a hint that it’s not just that we like interaction,” Wheatley says. “It’s important to keep us healthy and sane.” Part of the tendency toward studying solitary brains is due to a lack of ways to tease apart life’s rich social interactions. Functional MRI brain scanners are built for one person at a time, for example, and they usually can’t accommodate the movement that comes from talking.
4-8-19 When an older person’s brain waves are in sync, memory is boosted
A brain stimulating technique could lead to noninvasive therapies for dementia. Nudging an older person’s brain waves into sync temporarily boosts her recall powers. After about a half hour of precisely calibrated stimulation, people were better able to mentally juggle images seen on a screen, researchers report April 8 in Nature Neuroscience. The results are the latest example of technology that aims to improve thinking by reshaping brain waves, an approach that may ultimately lead to noninvasive therapies for disorders including dementia, schizophrenia and autism. In the new study, researchers attempted to synchronize brain wave patterns of 42 people who were 60 to 76 years old. External electrodes on a head cap delivered an alternating electric current designed to coordinate brain waves in two parts of the brain: the left prefrontal cortex and the left temporal cortex, both thought to be involved in working memory. After 25 minutes of stimulation, these older people could better remember whether an image on a screen was the same as a previous version, or slightly changed. Their performance on the task rivaled that of people in their 20s, report neuroscientists Robert Reinhart and John Nguyen, both of Boston University. When 18 younger people’s brain waves were thrown out of whack with the device, their working memory suffered, other experiments revealed. Brain stimulation benefits lasted at least 50 minutes. In a news conference with reporters on April 2, Reinhart said he suspects that the benefits last longer than that.
4-8-19 3D facial analysis could help identify children with rare conditions
Children with rare conditions could be diagnosed quicker thanks to 3D facial analysis software. Richard Palmer at Curtin University in Western Australia and his colleagues have developed a tool that can spot subtle, but important, differences in facial geometry. Around one in three rare and genetic diseases show up in facial features. For example, Foetal Alcohol Spectrum Disorders (FASD), a group of conditions caused by alcohol exposure in the uterus, often leads to a thin upper lip, a smoother area between the top lip and bottom of the nose and a shorter distance between the corners of the eyes. The team’s tool, called Cliniface, scans a person’s face. It then creates a 3D image of the face and measures the distances between the person’s facial features. It compares this with the average measurement for their age, sex and ethnicity. The way you would expect a face to change as someone ages depends on their ethnicity and sex. If the measurements taken by Cliniface are too far from the average for someone in that demographic, it will flag the deviations and label the symptom. A human clinician would still make the diagnosis. At the moment, the tool uses databases with predominantly European Caucasian measurements, but Palmer says users can add other databases to the system. “Many of the syndromes we deal with are incredibly rare, so as an individual clinician you may not have seen the condition the patient in front of you has,” says Natasha Brown at the Victorian Clinical Genetic Service in Australia, who wasn’t involved in the work. Currently, diagnosing some conditions requires doctors to measure the face with callipers and look at a set of reference images, which is a difficult process.
4-8-19 A common food additive may make the flu vaccine less effective
Mice eating the preservative had more inflammation and took longer to recover from the flu. A common food additive may make it more difficult to fight the flu. Vaccinated mice that got food containing the additive, tert-butylhydroquinone (tBHQ), took three days longer to recover from the flu than mice that ate tBHQ-free food. The unpublished result suggests the common additive may make flu vaccines less effective, toxicologist Robert Freeborn of Michigan State University in East Lansing reported April 7 at the 2019 Experimental Biology meeting. The additive helps stabilize fats and is used as a preservative for a wide variety of foods, including some cooking oils, frozen meat products — especially fish fillets — and processed foods such as crackers, chips and other fried snacks. Food manufacturers aren’t required to put the ingredient on labels, so “it’s hard to know everything it’s in,” says Freeborn. In separate experiments, unvaccinated mice eating tBHQ in their food had more virus RNA in their lungs than mice that didn’t eat it. The tBHQ eaters also had inflammation and increased mucus production deeper in their lungs than usual, Freeborn and colleagues found. The researchers don’t know exactly how the additive hampers flu fighting, but it may be because it increases activity of an immune system protein called Nrf2. Increased activity of that protein might reduce the number of virus-fighting immune cells in the mice. That possibility remains to be tested.
4-8-19 NASA says the International Space Station is covered in bacteria
There are currently six astronauts on board the International Space Station, but they are not alone. NASA has created a comprehensive catalogue of all the microbes on the space station, and found it is teeming with non-human life. The agency hopes this knowledge will help it develop safety precautions for future long-term space travel, such as sending humans to Mars. Microbes thrive on the ISS thanks to its unique combination of microgravity, radiation and tightly confined living space. A lack of competition from microbes normally found on the ground also helps certain strains to spread. To understand which bacteria and fungi are present on the ISS, Kasthuri Venkateswaran at NASA’s Jet Propulsion Laboratory in California and his colleagues asked astronauts to take samples from eight different locations on the space station. Some were in high-traffic places, such as the bathroom and dining table, while others were in less frequented storage areas. Using sterile wipes, astronauts took samples at three time periods – two a few months apart in 2015, and a third a year later. The specific locations were marked so that even when the crew changed, new astronauts knew exactly where to take samples from. For the first time, the team used sequencing methods to identify microorganisms that can’t be grown in a Petri dish, which they estimate make up between 40 and 60 per cent of all microbes on the ISS. They found hundreds of thousands of strains. “The majority of bugs we see on the ISS are benign, as we see in our home or office,” says Venkateswaran. It is likely they have been there since humans first started inhabiting the space station in 2000, he says.
4-7-19 Here are 5 RNAs that are stepping out of DNA’s shadow
These molecules play crucial roles in human health and disease. DNA is the glamour molecule of the genetics world. Its instructions are credited with defining appearance, personality and health. And the proteins that result from DNA’s directives get credit for doing most of the work in our cells. RNA, if mentioned at all, is considered a mere messenger, a go-between — easy to ignore. Until now. RNAs, composed of strings of genetic letters called nucleotides, are best known for ferrying instructions from the genes in our DNA to ribosomes, the machines in cells that build proteins. But in the last decade or so, researchers have realized just how much more RNAs can do — how much they control, even. In particular, scientists are finding RNAs that influence health and disease yet have nothing to do with being messengers. The sheer number and variety of noncoding RNAs, those that don’t ferry protein-building instructions, give some clues to their importance. So far, researchers have cataloged more than 25,000 genes with instructions for noncoding RNAs in the human genome, or genetic instruction book (SN: 10/13/18, p. 5). That’s more than the estimated 21,000 or so genes that code for proteins. Those protein-coding genes make up less than 2 percent of the DNA in the human genome. Most of the rest of the genome is copied into noncoding RNAs, and the vast majority of those haven’t been characterized yet, says Pier Paolo Pandolfi of Boston’s Beth Israel Deaconess Medical Center. “We can’t keep studying just two volumes of the book of life. We really need to study them all.” Scientists no longer see the RNAs that aren’t envoys between DNA and ribosomes as worthless junk. “I believe there are hundreds, if not thousands, of noncoding RNAs that have a function,” says Harvard University molecular biologist Jeannie Lee. She and other scientists are beginning to learn what these formerly ignored molecules do. It turns out that they are involved in every step of gene activity, from turning genes on and off to tweaking final protein products. Those revelations were unthinkable 20 years ago.
4-7-19 Will the tiny inherit the Earth?
Bigger species have all the advantages. But they might just be outlived. As I scuba dive in Oslob Bay off Cebu Island in the Philippines, I see a tiny shadow dart over the surface of the spherical coral block — a minute fish, a goby of the genus Eviota, among the smallest vertebrates in existence, only about a centimeter long and weighing less than 1/10th of a gram. It's about a million times smaller than myself, with the same basic vertebrate body: a spinal cord, a bony skull, a brain, kidneys, and a liver. With the exception of gills and lungs, the tiny fish and I share similar sets of organs, just at a very dissimilar size. But looking at gobies is not why I came to Oslob. I leave the coral block, and swim towards the shore as the sun darkens — not because of clouds but, rather, a truly gigantic fish swimming directly above me. It's what I had hoped to see: a whale shark, Rhincodon typus, the largest living fish. Large adults weigh up to 34 tons, more than 300 times my own weight. The difference in weight between the tiny goby and the whale shark is a startling eight orders of magnitude. Some truly gigantic animals populate the Earth. These massive disparities in animal sizes have fascinated biologists for more than a century. And there are enormous advantages that come with being large. Big animals have an easier time avoiding predators: Some of the tiny gobies have an attrition rate to predation of more than 6 percent per day, while whale sharks live for decades, and are known to have survived tiger shark attacks. Bigger animals can also invest more in reproduction: While a female goby's body produces only about 250 tiny eggs per lifetime to hatch into larvae, a female whale shark can give birth to a few hundred fully developed shark pups in a lifetime, each more than half a meter in length. And there are more advantages to a big body size. In large warm-blooded animals, maintaining a constant body temperature is easier due to their better surface-to-volume ratio. And in large herbivores, the larger volume of the intestines leads to more effective fermentation processes, which are needed to break down plant material. It pays to be big. Indeed, many lineages of animals have vastly increased in size during the course of their evolution. This trend is called Cope's rule, named after the 19th-century paleontologist Edward Drinker Cope. Prominent examples of lineages following Cope's rule are dinosaurs, which originated from an already sizeable two-meter-long reptile alive in the mid-Triassic (231 million years ago). During the following 165 million years, dinosaurs evolved into the largest land animals ever, the Titanosaurs (up to 37 meters long), and the largest land predator ever, the mighty Tyrannosaurus rex. Another striking example are the cetaceans: whales and dolphins. These secondary marine mammals descended from a cat-sized amphibious omnivore roaming around India 48 million years ago called Indohyus. When becoming fully aquatic, the cetaceans' size increased, with the ancient Basilosaurid whales 41 million years ago already up to 25 meters long. The size increase of baleen whales further accelerated during the past 10 million years, and today's blue whale is the largest animal to ever live, with adults attaining lengths of up to 30 meters and weighing close to 200 tonnes. Given all these advantages of large body sizes, an obvious question to ask is: Why aren't all animal species big? One reason is that species of small animals give rise to new species more rapidly. In a recent theoretical study, we connected the well-established fact that small animals are more numerous (there are more gobies than whale sharks in the ocean) to the insight that larger populations give rise to new species — a process called speciation — at a faster rate.
4-5-19 Doctors in China are using 5G internet to do surgery from far away
The future of surgery could be remote. Doctors in China successfully directed a team hundreds of kilometres away to perform heart surgery using a 5G mobile internet connection. This follows on from a surgeon who recently used the same technology to remotely control a surgical robot during a procedure. The appeal of long-distance surgery is that the leading specialist can help with or even intervene in operations far away from where they live. But having a reliable and fast enough connection has been a stumbling block. On 3 April, cardiologist Huiming Guo directed surgery on a 41-year-old woman who had a hole in her heart due to a birth defect. Guo was in Guangdong General Hospital in Guangzhou, whilst the patient was in Gaozhou People’s Hospital about 400 kilometers away. Before the procedure, Guo’s team worked out a surgical plan based on a 3D model of the defected heart. The model was put together by an artificial intelligence using medical images such as CT and MRI scans and then 3D printed, according to a press conference held on Wednesday in Guangzhou. Guo and his colleagues gave instructions, such as where to make cuts and stitches, through video conference to the operating team whilst watching a live-stream from the operating room in 4K—ultra-high definition. The team also monitored the procedure via a live video from a camera probe inserted through the patient’s chest and heart ultrasound. The surgery lasted 4 hours. “Advanced internet technology can save our doctors a lot of time because they don’t have to travel as much. They can use that time to safe more lives,” said Zhiwei Zhang at Guangdong General Hospital in a press conference. A similar surgery to correct a patient’s deformed chest wall was performed at Yangshan Hospital in Guangdong with doctors 200 kilometers away in Second People’s Hospital in Guangdong giving instructions. (Webmaster's comment: They didn't copy this from the United States. They have now taken the lead in almost all technolgy. We should be copying them!)
4-5-19 Early trauma and the brain
Trauma suffered during childhood may cause physical changes to the brain that make the victim more susceptible to depression later in life. That’s the conclusion of a new study by scientists at the University of Münster in Germany, reports USNews.com. The research involved 110 adults, ages 18 to 60, who had been hospitalized for serious depression. The participants completed a detailed questionnaire about early life trauma—including physical or emotional abuse or neglect, or sexual abuse—and received an MRI scan to assess their brain structure. The scans revealed that those who had experienced some form of childhood abuse tended to have a smaller insular cortex, a part of the brain connected to emotion and stress. Researchers also monitored the patients for further bouts of serious depression over the next two years and again found that those who had a history of childhood abuse were more likely to relapse. “Given the impact of the insular cortex on brain functions such as emotional awareness,” says study leader Nils Opel, “it’s possible that the changes we saw make patients less responsive to conventional treatments.”
4-5-19 Our regenerating brains
For decades, neuroscientists have argued over whether or not humans can make new neurons after their brains stop developing in adolescence. Now a team of Spanish scientists has found evidence that we do keep making fresh neurons well into our 90s, reports BBC.com, and that production drops rapidly in people with Alzheimer’s—even when the disease has only recently taken hold. The researchers examined the brains of 58 people who died at ages 43 to 97, focusing on the hippocampus, a part of the brain involved in memory and emotion. The researchers were able to spot immature, or “new,” neurons and noted that their production declined slightly with age in healthy brains. “I believe we would be generating new neurons as long as we need to learn new things,” says co-author Maria Llorens-Martín, from the Autonomous University of Madrid. “And that occurs during every single second of our life.” But the brains of people at the very beginning of Alzheimer’s—when symptoms have not yet manifested—had 30 percent fewer new neurons than healthy brains of the same age. By measuring levels of new brain cells, doctors might eventually be able to diagnose Alzheimer’s at an earlier stage than currently possible and recommend exercise and other interventions to boost neuron production.
4-5-19 An Elegant Defense: The Extraordinary New Science of the Immune System
If you don’t understand the human immune system, don’t feel too bad, said Dan Friedman in the Los Angeles Review of Books. “After all, you’re no different from most scientists until the very recent past.” But that’s why Matt Richtel’s new book is so useful. Immunology has been transformed in the past decade by discoveries that may soon enable medical professionals to outsmart cancer, AIDS, and other deadly diseases. Richtel, a Pulitzer Prize–winning New York Times reporter, “has exactly the right set of tools” to demystify the science. And because Richtel focuses on four people who were gravely afflicted or miraculously saved by their immune systems, the learning arrives alongside “deeply affecting” drama. Richtel begins by introducing Jason, a friend of his since childhood, said Matt McCarthy in USA Today. Jason was in his mid 40s when he was diagnosed with Hodgkin’s lymphoma, and by the time we meet him he is ready to take a chance on an experimental drug that promises to disrupt cancer’s power to trick the immune system into helping it grow. We also meet Merredith Branscombe and Linda Segre, both debilitated by immune systems that are attacking their healthy cells. Together with Bob Hoff, whose immune system has somehow kept HIV in check, these four provide what Richtel calls “a kind of immunological Goldilocks story”—a chance to see the effects of individual immune systems that are too weak, too strong, and just right. He offers some more curious analogies as well, likening autoimmune disorders to xenophobia and even Nazism. “Yet it’s this outside-of-the-box thinking that makes Richtel’s book so rich and engaging.”
4-5-19 Peruvian fossils yield a four-legged otterlike whale with hooves
The find is the oldest whale skeleton in the New World. An ancient four-legged whale walked across land on hooved toes and swam in the sea like an otter. The newly discovered species turned up in 2011 in a cache of fossilized bones in Playa Media Luna, a dry coastal area of Peru. Jawbones and teeth pegged it as an ancient cetacean, a member of the whale family. And more bones followed. “We were definitely surprised to find this type of whale in these layers, but the best surprise was its degree of completeness,” says Olivier Lambert, a paleontologist at the Royal Belgian Institute of Natural Sciences in Brussels. Jaw, tooth and spine features, described April 4 in Current Biology, don’t quite match anything else in the fossil record, setting the skeleton apart as a new species, dubbed Peregocetus pacificus (meaning “the traveling whale that reached the Pacific Ocean”). At 42.6 million years old, it’s the oldest whale skeleton found in the New World, though some fossilized whale teeth from North America may be even older. Big, possibly webbed feet and long toes would have allowed P. pacificus to dog-paddle or swim freestyle. And like modern otters and beavers, this whale’s vertebrae suggest that its tail also functioned as a paddle. With tiny hooves and strong legs and hips, the animal could walk on land. But “it was definitely a better swimmer than walker,” Lambert says. Whales got their start on land and gradually adapted to a water-dwelling lifestyle. The first amphibious whales emerged more than 50 million years ago near what’s now India and Pakistan. The new species shares some similar features with Maiacetus and Rodhocetus, two early whales from that area. P. pacificus’ age supports the idea that whales migrated across the South Atlantic and around South America to the Pacific Ocean in their first 10 million years of existence.
4-5-19 Fossil treasure trove
A “mind-blowing” haul of fossils that includes dozens of species never seen before has been discovered in China, offering a glimpse at the sheer diversity of life on Earth some 500 million years ago. The new site, called Qing jiang, sits on the banks of the Dan shui River in southern China. It is one of only a handful of sites worldwide that offer a glimpse into the Cam brian explosion, the massive burst in animal diversity at the dawn of animal life. Paleontologists have so far unearthed 4,351 fossils, representing 101 different species, 53 of them new. The creatures, which were likely entombed and preserved by an underwater mudslide 518 million years ago, include primitive forms of jelly fish, worms, and arthropods. The animals are so well preserved that their soft tissues—including muscles, guts, and gills—are still visible. “Most fossil localities throughout all of time are going to preserve the shelly things, the hard things,” Joanna Wolfe, a Har vard paleontologist who wasn’t involved in the study, tells National Geographic. But the fossils at Qing jiang “give you anatomy. These are the best of the best.”
4-5-19 Telling us to stop washing our hands is dangerous and unacceptable
Media misinterpretations of the hygiene hypothesis are encouraging us to stop washing our hands - and it's undermining our public health, says Sally Bloomfield. “Two-second rule!” our children shout as they snatch food off the floor and pop it into their mouths. It is oft stated that our lives and homes are too clean, that we need to get dirtier for the sake of our health. You have probably heard it referred to as the hygiene hypothesis. This concept, first introduced back in 1989, was quite specific, proposing that rising levels of allergies might be linked to lack of exposure to childhood infections, due to higher standards of hygiene. This hypothesis is now known to be incorrect. Yes, microbes and our contact with them is vital to our health, but the devil is in the detail. It is now thought that during human evolution, microbes evolved an essential role in regulating our immune system. The most promising theories suggest that the microbes involved in this aren’t those that cause infections, but friendly microbes that make up our diverse human microbiome. These are acquired by exposure to other people and animals, and from our natural environment. They ensure that our immune system doesn’t overreact to harmless stimuli like pollen, foods and our own tissues. Without them, we are at higher risk of developing allergies and immune disorders like type 2 diabetes or multiple sclerosis. A range of lifestyle changes including an increase in C-section births, less breastfeeding, smaller family sizes and less time outdoors are now seen as the likely causes of reduced exposure to friendly microbes, together with altered diet and antibiotic use, which adversely affect the composition of our microbiome. But there is little evidence that personal or household cleanliness – as suggested by the hygiene hypothesis – is involved. The common childhood infections that hygiene measures are designed to combat appeared much too late in our evolutionary history to have evolved an essential role in the development of our immune system.
4-5-19 Testing mosquito pee could help track the spread of diseases
West Nile and other diseases were detected in excretions from wild insects caught in traps. There are no teensy cups. But a urine test for wild mosquitoes has for the first time proved it can give an early warning that local pests are spreading diseases. Mosquito traps remodeled with a pee-collecting card picked up telltale genetic traces of West Nile and two other worrisome viruses circulating in the wild, researchers in Australia report April 4 in the Journal of Medical Entomology. The tests were based on an innovative saliva monitoring system unveiled in 2010: traps that lure mosquitoes into tasting honey-coated cards. Among its advantages, this card-based medical testing doesn’t need the constant refrigeration that checking whole mosquitoes does. And it’s not as labor intensive as monitoring sentinel chickens or pigs for signs of infection. But testing traces of mosquito saliva left on these cards comes close to the limits of current molecular methods for detecting viruses. In part, it’s an issue of volume. A mosquito drools fewer than five nanoliters of saliva when it tastes a card. In comparison, mosquitoes excrete about 1.5 microliters of liquid per pee, offering a veritable flood of material. So Dagmar Meyer of James Cook University in Cairns, Australia and her colleagues created urine collectors using standard overnight light traps and longer-standing traps that exhale delicious carbon dioxide, a mosquito come-hither. The team set out 29 urine traps in two insect-rich spots in Queensland along with traps equipped to catch mosquito saliva. When mosquitoes fell for the trick and entered a urine trap, their excretions dripped through a mesh floor onto a collecting card. Adding a moist wick of water kept trapped mosquitoes alive and peeing longer, thus improving the sample. Pee traps picked up three viruses — West Nile, Ross River and Murray Valley encephalitis — while the saliva ones detected two, the researchers report.
4-5-19 50 years ago, scientists were unlocking the secrets of bacteria-infecting viruses
Excerpt from the April 5, 1969 issue of Science News. Viruses, which cannot reproduce on their own, infect cells and usurp their genetic machinery for use in making new viruses.... But just how viruses use the cell machinery is unknown.… Some answers may come from work with an unusual virus, called M13, that has a particularly compatible relationship with ... [E. coli] bacteria. — Science News, April 5, 1969. M13 did help unlock secrets of viral replication. Some bacteria-infecting viruses, called bacteriophages or simply phages, kill the host cell after hijacking the cell’s machinery to make copies of themselves. Other phages, including M13, leave the cell intact. Scientists are using phage replication to develop drugs and technologies, such as virus-powered batteries (SN: 4/25/09, p. 12). Adding genetic instructions to phage DNA for making certain molecules lets some phages produce antibodies against diseases such as lupus and cancer. The technique, called phage display, garnered an American-British duo the 2018 Nobel Prize in chemistry (SN: 10/27/18, p. 16).
4-5-19 Fossil of ancient four-legged whale found in Peru
The fossil of a 43-million-year-old whale with four legs, webbed feet and hooves has been discovered in Peru. Palaeontologists believe the marine mammal's four-metre-long (13 ft) body was adapted to swim and walk on land. With four limbs capable of carrying its weight and a powerful tail, the semi-aquatic whale has been compared to an otter or a beaver. Researchers believe the discovery could shed light on the evolution of the whale and how it spread. "This is the most complete specimen ever found for a four-legged whale outside of India and Pakistan," Dr Olivier Lambert, a scientist at the Royal Belgian Institute of Natural Sciences and co-author of the study, said. It was found in marine sediments 1km (0.6 miles) inland from Peru's Pacific coast, at Playa Media Luna. The location has piqued researchers' interest as the first whales are thought to have first evolved in South Asia around 50 million years ago. As their bodies became better suited to water, they migrated further afield to North Africa and North America, where fossils have been found. The latest discovery suggests early whales managed to swim there from South America. "Whales are this iconic example of evolution," Travis Park, an ancient whale researcher at the Natural History Museum in London, said. "They went from small hoofed mammals to the blue whale we have today. It's so interesting to see how they conquered the oceans."
4-4-19 How emus and ostriches lost the ability to fly
Changes in regulatory DNA, not gene mutations, are the culprit, scientists say. Evolutionary tweaks to DNA that bosses genes around may have grounded some birds. New genetic analyses show that mutations in regulatory DNA caused ratite birds to lose the ability to fly up to five separate times over their evolution, researchers report in the April 5 Science. Ratites include emus, ostriches, kiwis, rheas, cassowaries, tinamous and extinct moa and elephant birds. Only tinamous can fly. Regulatory DNA gets its name because it’s involved in regulating when and where genes are turned on and off. It doesn’t contain instructions for making proteins. Researchers have long debated whether big evolutionary changes, such as gaining or losing a trait like flight, occur mostly because of mutations to protein-making genes tied to the trait, or result mainly from tweaks to the more mysterious regulatory DNA. Revealing the importance of regulatory DNA in shaping evolution could shed light on how closely related species with the same genes, such as chimps and humans or moas and tinamous, can develop vastly different looks and abilities. Scientists have tended to stress the importance of protein-coding changes affecting the evolution of various traits in many organisms. Examples are relatively easy to find. For instance, a previous study of flightless Galápagos cormorants suggested that mutations in a single gene shrank the birds’ wings (SN: 6/11/16, p. 11). In general, mutations that alter proteins are likely to be more damaging than changes to regulatory DNA, and thus easier to spot, says Camille Berthelot, an evolutionary geneticist at the French national medical research institute INSERM in Paris. A protein may be involved in many biological processes throughout the body. “So everywhere this protein is [made], there’s going to be consequences,” she says.
4-4-19 Scotland's HPV vaccine linked to 'near elimination' of cervical cancer
The routine vaccination of schoolgirls against the human papillomavirus (HPV) in Scotland has led to a dramatic reduction in cervical cancer in later life. Some forms of the sexually-transmitted HPV are linked to cervical cancer – one of the most common cancers in women aged under 35 in the UK. A decade ago, the UK government introduced a UK-wide immunisation programme for girls aged 12 and 13. Compared with unvaccinated women born in 1988, vaccinated women born in 1995 and 1996 showed reductions of up to 90 per cent in cases of cervical intraepithelial neoplasia (CIN), a pre-cancerous abnormal growth of cells and lesions on the cervix linked to invasive cervical cancer. Unvaccinated women also showed a reduction in disease. The researchers say this suggests routinely vaccinating girls aged 12 and 13 in Scotland has created substantial “herd protection”. The findings were made by Tim Palmer at the University of Edinburgh and his colleagues by analysing vaccination and screening records for 138,692 women born between 1988 and 1996, who had a screening test at age 20. The study’s co-author, Kevin Pollock at Glasgow Caledonian University, says the HPV vaccine has exceeded expectations. “[The vaccine] is associated with near elimination of both low and high-grade cervical disease in young Scottish women eight years after the vaccine programme started.” Cervical cancer cases in women in Scotland aged 20-24 have reduced by 69 per cent since 2012. Scotland’s public health minister Joe FitzPatrick says the programme will be enlarged. “We are, of course, building on this success and extending the HPV vaccine programme to boys later this year.”
4-4-19 People with autism are less likely to fall for an out-of-body illusion
People with autism don’t seem to experience a virtual reality illusion about their body that people who don’t have autism usually fall for. Some autistic people view autism as a different way of seeing the world. Jane Aspell at Anglia Ruskin University in the UK and her team wondered if people with autism may perceive a particular illusion differently. This illusion involves wearing virtual reality goggles that let you view your own body as if you are looking at someone else. Wearers of the goggles see this avatar being stroked on its back, at the same time as their own back is stroked in real life. This commonly makes people feel like they are starting to embody the virtual avatar, and their sense of where they are located shifts towards it. Aspell’s team recreated this illusion for 51 volunteers, about half of whom had autism. Questionnaires afterwards found that the autistic participants weren’t susceptible to the illusion. This suggests that, in autism, “the way the brain is generating a sense of self is somehow different”, says Aspell. Before the virtual reality task, the volunteers were asked to carry out a test that measured the size of the area surrounding them that they unconsciously saw as personal space. “Our sense of self doesn’t end at the skin – there’s a hazy bubble around us,” says Aspell. The volunteers with autism had a personal space about 10 centimetres smaller than those who didn’t have the condition. Other work has shown people with autism are also less susceptible to the “rubber hand illusion”, a similar scenario to the virtual body illusion that tricks people into feeling that a rubber hand is their own hand.
4-4-19 Had a genetic test? You should be told if its implications change
Genetic test results that once seemed life-threatening now look less risky. Guidance on what to tell people doesn't go far enough, say Rachel Horton and Anneke Lucassen. Imagine a doctor tells you that you have a version of a gene called BRCA1 that means you have a high chance of developing breast and ovarian cancer. You might make choices about screening or surgery. You might tell your family so they can get tested too. But now imagine that new evidence suggests that your risk of cancer is far lower than was thought when you had your test a few years ago. Would you want to know? People often expect genetic results to be certain, but sometimes this isn’t the case. As it gets quicker and cheaper to analyse the genetic code, we are gathering more data about the wide range of genetic variation, and finding that the context in which genetic variants are found can determine how serious they are. Our understanding can change even for variants in well-known genes like BRCA1: some of these have turned out not to be as closely linked to cancer as we thought a few years ago. As clinicians researching ethical issues, we are interested in what should happen in situations like this. Should people be re-contacted if interpretation of their genetic results changes? How significant does the change need to be? We don’t want people’s health choices to be based on inaccurate information. But equally, contacting a person might be stressful for them, especially if they have already made big decisions based on their old result.
4-4-19 Amazing four-legged fossil shows how walking whales learned to swim
A fossil of a 43-million-year-old whale that was still able to walk on land on four legs has been found in Peru. It is the first amphibious whale found in the southern hemisphere, and suggests that whales managed to swim across the South Atlantic early in their evolution. The 3-metre-long animal looked a bit like an otter or a beaver, with four legs and a large tail for swimming. “It was still capable of bearing its weight on its limbs,” says Olivier Lambert at the Royal Belgian Institute of Natural Sciences, a member of the team that made the discovery. “It was intermediate between fully walking and fully aquatic.” Whales started evolving in South Asia around 50 million years ago, from a dog-like creature related to deer and hippos. As they became more aquatic, these early whales began spreading along coasts. Fossils of semi-aquatic whales have recently been found in West Africa. The latest discovery suggests that these early whales managed to swim from there to South America at least 43 million years ago. At the time, the West African coast was just 1200 kilometres from what is now Brazil, and there was a westward current. But it would still have taken a week or two to make the crossing. That may suggest that these whales were already capable of surviving without fresh water, and of sleeping at sea. They soon reached North America too, where fossil teeth dating to around 41 million years ago have been found. The last common ancestor of all modern whales and dolphins lived 37 million years ago, so the new discovery may be one of the ancestors of modern whales. However, it is far more likely to be a cousin – a member of a side branch that died off, says Lambert.
4-3-19 It's not an illusion, you have free will. It's just not what you think
The idea that free will doesn't exist is based on misguided intuitions of what it means to be a biological machine, as a famous insect, the digger wasp, reveals. A SIMPLE insect can help us understand free will, and the lack of it. When a female digger wasp is ready to lay her eggs, she hunts down a cricket or similar prey, paralyses it with a sting, drags it back to the lip of her burrow, and then enters to check for blockages. If you move the cricket a few centimetres away before she re-emerges, she will again drag it to the threshold and again leave it to check for blockages. She will do this over and over. The wasp has no choice. This mindlessly inflexible behaviour has led to the wasp, Sphex ichneumoneus, becoming a byword among biologists for determinism, the idea that what we think of as a “choice” is in fact a path dictated by pre-existing factors. It is tempting to think that we aren’t like the wasp – that what we do is the result of choices that are freely made. Yet the more we learn about the neuroscience of decision-making, the more “sphexish” we seem to be. You hear people arguing that humans are mere biological machines trapped in cycles of behaviour that are ultimately beyond our control – that free will is just an illusion. As a cognitive scientist who studies decision-making, I disagree. Of course, humans are animals. The problem, I believe, is our misguided intuitions of what it means to be a biological machine. In an attempt to dispel some of these misconceptions, I have created an interactive essay on Twitter called The Choice Engine. How Sphex came to be linked with free will is a long story. Charles Darwin was studying this wasp while working on his theory of evolution. We know from his notebooks that its behaviour had a big impact on him. He wasn’t aware that it would ceaselessly check its burrow – that discovery was made decades later by Nikolaas Tinbergen, the founder of ethology, the science of animal behaviour. What interested Darwin was what the wasp does once it has dragged a cricket into its burrow: it lays its eggs in the body of the immobilised but still living prey. When the larvae hatch they eat it from the inside out.
4-3-19 What we know and don’t know about how mass trauma affects mental health
Researchers are trying to figure out who is most at risk of self-harm. In March, three people connected to mass school shootings died by suicide, raising questions about the lingering effects of such trauma on a person’s mental health. Two teenagers who survived the 2018 shooting at Marjory Stoneman Douglas High School in Parkland, Fla., took their own lives within days of each other. The father of a child killed in the 2012 Sandy Hook Elementary School shooting in Newtown, Conn., died by suicide a few days later. Suicide can occur in clusters, especially among teens. But it’s too early to tell if these deaths are connected in any way, are related to having experienced similar mass traumas — or if they simply occurred close together by chance, says April Foreman. A psychologist in Baton Rouge, La., and board member of the American Association of Suicidology, Foreman is familiar with all three suicides. “These are really complicated events,” she says. (One thing they aren’t, some researchers say, is contagious; a person can’t catch suicide like a common cold.) But the deaths do shine light on a question that researchers are trying hard to answer: How does being connected to a mass trauma event like a school shooting affect a person’s later risk for mental health problems and self-harm? Here’s what scientists know — and don’t know.
- Who is most at risk for developing mental health problems following a mass shooting?
- Who is most at risk for self-harm, including suicide?
- Are teens at greater risk for self-harm following a mass shooting than adults?
- What drives clusters of suicides?
- How do we help those most at risk?
- The shootings happened a while ago. Why are we seeing these suicides now?
- Should everyone connected to a mass shooting receive mental help?
4-3-19 Mystery illnesses reveal the power of our minds to influence health
A group of troubling disorders cause very real symptoms, but have no discernible physical cause. Finding out why is revealing how we can all unlock the power of mind over matter. AMANDA PAYNE’S seizures weren’t going away, despite taking strong epilepsy drugs. One time she felt the warning signs just before getting off a bus on a busy road in Glasgow. She only just made it to the pavement before collapsing and convulsing. Payne was sent for further investigations. Like many people with epilepsy, she had been diagnosed based on a history of sudden blackouts, but had never undergone a definitive test to record her brain’s electrical activity during such an episode. This time, she was admitted to hospital where she wore electrodes on her head for four days. By the end the doctors knew one thing: whatever was wrong, it wasn’t epilepsy. Despite four years of apparent seizures, her brain was to all appearances working fine. As to the real problem, the doctors had no simple explanation. But they had seen this before. Payne is one of a group of people with neurological symptoms – those affecting the nervous system – that defy all the usual medical tests. As well as seizures, other manifestations include paralysis, tremor, blindness and pain – but no physical cause can be found. Until recently, those who experienced these disorders were routinely dismissed by medical professionals as attention-seekers and fakers.
4-3-19 This Greek philosopher had the right idea, just too few elements
Empedocles didn’t make a periodic table, but identified basic concepts of matter and force. Long before there was a periodic table of the elements, there was no need for a table — just four chairs. From ancient through medieval into early modern times, natural philosophers could count the known elements with the fingers of only one hand (with no need for the thumb). All material reality, nearly every authority concurred, was built from only four elements. And those four elements had been identified in the fifth century B.C. by the imaginative and somewhat idiosyncratic Greek philosopher known as Empedocles of Acragas. Even though Empedocles had the true number of elements wrong, and the substances he identified aren’t actually elements anyway, he had more or less (less, I guess) the right idea. In fact, stripped of the literary embellishment in his poetic metaphors (and ignoring a few really weird ideas that didn’t make much sense), Empedocles articulated much of what passes today for sound scientific concepts. He basically identified the essence of modern notions of matter and force, and he dreamed up a theory of the universe that shares features with some current cosmological speculations.
4-3-19 Mystery illnesses show how you can think yourself ill - and well again
AMANDA PAYNE’S seizures weren’t going away, despite taking strong epilepsy drugs. One time she felt the warning signs just before getting off a bus on a busy road in Glasgow. She only just made it to the pavement before collapsing and convulsing. Payne was sent for further investigations. Like many people with epilepsy, she had been diagnosed based on a history of sudden blackouts, but had never undergone a definitive test to record her brain’s electrical activity during such an episode. This time, she was admitted to hospital where she wore electrodes on her head for four days. By the end the doctors knew one thing: whatever was wrong, it wasn’t epilepsy. Despite four years of apparent seizures, her brain was to all appearances working fine. As to the real problem, the doctors had no simple explanation. But they had seen this before. Payne is one of a group of people with neurological symptoms – those affecting the nervous system – that defy all the usual medical tests. As well as seizures, other manifestations include paralysis, tremor, blindness and pain – but no physical cause can be found. Until recently, those who experienced these disorders were routinely dismissed by medical professionals as attention-seekers and fakers. In the past decade, though, neurologists have come to understand how real these symptoms are, and how people with them experience injustice and abuse. This shift has led to techniques that help people regain control over their bodies. What’s more, it is shedding light on some puzzling bodily experiences we all may have and even the nature of consciousness itself. “An awful lot of strange things we have noticed about the brain might fall into place if this is right,” says Andy Clark, a cognitive scientist at the University of Edinburgh, UK.
4-3-19 Albino lizards are the world’s first genetically modified reptiles
The CRISPR genome-editing technique has been used to make the world’s first genetically modified reptiles: two albino lizards. The breakthrough may have a wide variety of uses, from studying human eye disorders to tackling invasive pythons. Our ability to tweak the genomes of animals like mice and zebrafish has been hugely useful for medical research. But there are some conditions that are hard to study in existing lab animals. For instance, people with albinism often have vision problems because the genetic variants that cause albinism affect the development of the fovea in the eye – the part of the retina that provides the most detailed picture of the world. Mice and zebrafish don’t have fovea – but lizards do. Until now, however, there has been no way to make deliberate changes to the genome of any reptile, because the techniques used in other animals don’t work as well for egg-laying animals. Douglas Menke at the University of Georgia and his team anaesthetised female brown anole lizards (Anolis sagrei) and injected the CRISPR genome-editing machinery directly into eggs developing in their ovaries. The trick is to inject eggs at the right stage of development. If it is done too soon, it doesn’t work well; too late and there is a high risk of damaging important structures inside the egg. The team used the technique to create albino lizards because their lack of pigmentation makes it easy to tell when the gene editing has worked, and because team member Jim Lauderdale hopes to use gene-edited lizards to study how albinism affects the fovea. In the team’s initial study, nine out of 146 eggs that were injected were successfully gene edited. The team says it has managed to improve this efficiency rate.
4-3-19 Two-million-year-old toothache may have killed an early human
It must have been agony. Two million years ago, an early human likely once tossed and turned, unable to sleep as the front of their mouth throbbed incessantly. Their teeth were worn down so much that root canals had been exposed. And above those upper incisors lay at least one dental abscess – a mass of pus growing inside the jaw, caused by bacterial infection. Of course, there were no dentists to relieve the pain. It’s possible the individual may even have eventually died from blood poisoning caused by the troublesome abscess. This is the sorry situation revealed by new analysis of a rare hominin specimen, SK 847, which was discovered in South Africa in 1969. Researchers recently inspected around 20 early human jaw fossils from southern Africa and found a rare example of a dental abscess in one, SK 847 – the specific species of the individual is disputed. The find may be the earliest dental abscess in the genus Homo ever found, though there is one other jaw bone of a similar age from Europe that also has signs of abscess-like formations. SK 847 definitely suffered from the condition, says Ian Towle at Liverpool John Moores University, as it has a small rim around a hole in the upper jaw. “That’s where the bone started to remodel where the abscess had been,” he says. “I knew straightaway that that one had formed during life.” The abscess appears to have been caused by bacteria attacking the individual’s teeth. The teeth themselves were likely worn down after eating hard, uncooked food that – thanks to a lack of culinary hygiene – probably also carried grit into the mouth.
4-3-19 Your heartbeat may help you sync up with other people to cooperate
Your heartbeat might help you cooperate. When we make a movement, even a small one, it is most likely to end exactly in the middle of each heartbeat – and this synchronisation happens when we watch someone else do the same behaviour. This could be how our bodies help us align our actions with others. “We don’t yet know if the heartbeat is guiding the action or responding to it,” says Eleanor Palser at the University of California San Francisco. She and her colleagues examined how heartbeats sync with actions using electrocardiograms (ECGs), which measure the electrical activity of the heart. Previous work has shown that heartbeats sync with walking speed, but this test measured heart activity while using fine motor skills. The team asked 26 people to sit in pairs across from each other at a table equipped with four touch-sensitive pads and a marble. The pairs took turns moving the marble from pad to pad after memorising a sequence on a screen. The team found that the end of each movement was significantly more likely to occur between heartbeats than during a heartbeat. They also found that the heartbeats of people who were watching their partner move the marble lined up with the action in the same way. Palser says these findings suggest our bodies may help us sync with others to perform a task. Some hypotheses suggest the synchronisation may be driven by a feedback loop between the heart and the brain, which involves cells called baroreceptors that signal the brain when the heart muscle contracts.
4-2-19 Health regulator takes step towards lifting vaginal mesh implant ban
The UK health regulator has taken the first step towards NHS England lifting a temporary ban on the use of vaginal mesh implants. The implants are used to treat incontinence and prolapse in women, often after childbirth. Their use was paused last year to allow for a safety review, after women reported severe pain and complications. Around one in 10 recipients have had complications within five years of surgery, according to one study. Now the National Institute for Health and Care Excellence (NICE) has said the ban could be lifted if certain conditions are met. These include establishing a national database to record procedures and complications, and that only specialist surgeons at specialist centres carry out the surgery. The guidelines also recommend that people are offered booklets, called “decision aids”, that clearly set out the possible risks of vaginal mesh implants. Women who opt for surgery over physical therapies should be warned that the implants may cause pain, including during sex. But campaigners say the new guidelines aren’t materially different from ones published 16 years ago. “They are so weak, they clear the way for the next generation of women to be harmed,” Kath Sansom of Sling The Mesh said in a statement.
4-2-19 Bacteria can be coaxed into making the toughest kind of spider silk
The engineered stands could help design more sturdy materials. Bacteria are helping to make engineered silk that rivals the strength and stretchiness of a spider’s stiff dragline silk, the type from which the arachnids dangle. Pound for pound, dragline silk is stronger and tougher than steel. Engineers have tried for decades to create a synthetic mimic from genetically modified bacteria, yeast and even goat milk, but have always fallen short. Part of the challenge is that the genetic information for dragline silk is a long string of repeating DNA. And those previously tested organisms’ cell machinery haphazardly alters or chops up such series. To overcome this issue, researchers precisely separated the repeating DNA into bits and inserted each repeating piece into an E. coli microbe. These smaller pieces were less likely to be further altered within the bacteria, and each microbe then followed the genetic instructions to produce a short strand of silk. The researchers added to the end of each strand a chemical tag that glued the individual fibers together. The resulting material behaved like dragline silk. Its tensile strength, or resistance to being pulled apart, was measured at 1.03 gigapascals, about the same as for naturally produced dragline silk. The engineered silk’s toughness measured 114 megajoules per cubic meter, compared with around 100 megajoules for silk made by spiders. And the engineered silk strands could stretch 18 percent before breaking, the same as natural dragline silk. “We can now use bacteria to produce something as good as nature,” says synthetic biologist Fuzhong Zhang of Washington University in St. Louis who presented the research April 2 at the American Chemical Society’s annual meeting in Orlando, Fla.
4-2-19 Foreigners may have conquered ancient Egypt without invading it
An analysis of teeth suggests the Hyksos dynasty arose from outsiders marrying into power. A mysterious foreign dynasty that ruled ancient Egypt for about a century gained power not by force, as often thought, but by marrying into royalty, new evidence suggests. Hyksos people, thought to have come from somewhere in West Asia, reigned as Egypt’s 15th dynasty from around 3,650 to 3,540 years ago. Although later, homegrown Egyptian pharaohs described these people as invaders, no remains of battles fought by Hyksos people against Egyptians have been found. An influx of mostly female immigrants may have occurred at Tell el-Dab’a, the former Nile Valley Hyksos capital, shortly before the foreigners took over. “Hyksos people in Egypt appear to have been an elite group that gained power from within,” biological anthropologist Christina Stantis of Bournemouth University in Poole, England, said March 29 at the annual meeting of the American Association of Physical Anthropologists. She and Bournemouth colleague Holger Schutkowski analyzed strontium in teeth from 71 individuals previously excavated at Tell el-Dab’a. Around half died within a few centuries before Hyksos rule; the rest died during the Hyksos dynasty. Measures of strontium, which gets absorbed into bones by regularly eating local plants and animals, are geographically distinct, indicating regions where people have lived. Twenty-one of 27 females interred in elite graves dating to shortly before Hyksos rule came from outside the Nile Valley, Stantis said. Only a few nonlocal, elite males came from that time period. That female-skewed immigration fits a scenario in which Hyksos women married into Egyptian royal families, she said.
4-2-19 New fossils may capture the minutes after the dinosaur-killing asteroid impact
A North Dakota site appears to hold fish, other organisms swiftly buried in the strike’s wake. About 66 million years ago, a giant asteroid smashed into Earth off the coast of what’s now Mexico. Less than an hour later, the impact sent water in a riverbed 3,000 kilometers away sloshing violently back and forth, swiftly burying freshwater fish, plants and other organisms in the heavy sediment, a new study finds. Evidence of those surges, as well as tiny traces of the impact itself, appear to be preserved in a meter-thick layer of rock in southwestern North Dakota. Set off by the impact, an immense earthquake — equivalent to a magnitude 10 or even 11.5 — sent seismic waves pulsing through Earth’s crust, triggering that sloshing, researchers argue online April 1 in the Proceedings of the National Academy of Sciences. If true, the scenario would add a new kill mechanism to the mass extinction event that marks the boundary between the Cretaceous and Paleogene Periods, often called the KPg. Some 75 percent of land-based species, including all nonbird dinosaurs, died in the event (SN: 2/4/17, p. 16). The site, found in the Hell Creek Formation and dubbed Tanis, represents a unique snapshot of what happened on land in the immediate aftermath of the impact, says paleontologist Robert DePalma of the University of Kansas in Lawrence. “It’s a critical moment in time,” DePalma says. “We have a high-resolution image of the first couple of hours after the impact. That level of detail is not really known elsewhere.”
4-2-19 Pre-eclampsia blood test could help diagnose the condition earlier
NHS England is rolling out a blood test for pre-eclampsia after a study showed it can help diagnose the pregnancy condition earlier. Pre-eclampsia is suspected in around 10 per cent of UK pregnancies, affecting approximately 80,000 women annually. The condition usually occurs during the second half of pregnancy, from around 20 weeks, or soon after a baby is delivered, and is characterised in part by high blood pressure and protein in the mother’s urine. Complications can cause premature birth and, in extreme cases, can kill the mother and baby. The new tool involves measuring a particular protein called placental growth factor (PlGF) in a woman’s blood. By doing this, a team at King’s College London were able to diagnose pre-eclampsia on average two days sooner. “For the last hundred years, we have diagnosed pre-eclampsia through measuring blood pressure and checking for protein in a woman’s urine. These are relatively imprecise and often quite subjective,” says Lucy Chappell at King’s. “We knew that monitoring PlGF was an accurate way to help detect the condition but were unsure whether making this tool available to clinicians would lead to better care for women. Now we know that it does,” she says. The team studied 1,035 women with suspected pre-eclampsia from 11 maternity units across the UK. The women were randomly split into two groups, one of which had the results of their PlGF test revealed to their medical teams. Their results showed the test reduced the average time to pre-eclampsia diagnosis from 4.1 days to 1.9 days. Serious complications before birth were reduced from from 5 per cent to 4 per cent.
4-2-19 A Nobel Prize winner argues banning CRISPR babies won’t work
A registry could keep human gene editing aboveboard, David Baltimore says. Scientists are vigorously debating how, and if, they can put the human gene-editing genie back in the bottle. There is widespread agreement that it’s currently “irresponsible” to make heritable changes in human cells. Gene editors, even the much lauded CRISPR/Cas9 molecular scissors, have not yet been proven safe and effective enough to use to alter genes in the human germline; embryos, eggs, sperm or the cells that give rise to eggs and sperm. But that didn’t stop Chinese scientist Jiankui He from announcing in 2018 the births of two gene-edited babies. Now in the wake of almost universal outrage over He’s actions, efforts are under way to prevent others from doing the same thing. Some scientists have recently proposed a temporary moratorium on editing that would result in babies that carry heritable changes. Such a ban would last for perhaps five years to buy enough time to improve the technology and to allow for public debate (SN Online: 3/13/19). An advisory committee to the World Health Organization has alternatively proposed a global registry of work on human gene editing. Such a database would provide transparency and a better understanding of the state of gene-editing science, committee representatives said in a news conference March 19. Science News talked with Nobel laureate David Baltimore, who is president emeritus of Caltech, about the ongoing debate. Baltimore, a virologist and immunologist, chaired two international summits on human gene editing. The interview has been edited for brevity and clarity.
4-1-19 Pumping may be linked to an altered microbial mix in breast milk
Milk from women who pump contains different amounts and types of bacteria than milk from women who breastfeed their babies directly, a study finds. In the midst of breastfeeding my third child, I once started to calculate how many hours of my life I’ve spent attached to a breast pump. I quickly and smartly gave up, after realizing that “a lot” was a satisfying answer. Like many mothers who breastfeed, I’ve relied on pumping multiple times a day to express milk for my babies’ bottles. And probably like many mothers, I’ve wondered whether those bottles are the same as nursing directly. The answer, at least in some aspects, is no, according to a new study that compares the microbial makeup of pumped breast milk with that of milk received directly from the breast. Milk from breastfeeding women who do not pump and milk from women who pump at all (exclusively, occasionally or infrequently) differed in their bacterial makeup, researchers reported February 13 in Cell Host & Microbe. That finding, taken from 393 mother-baby pairs in a larger dataset called the CHILD study, suggests that all breast milk is not, strictly speaking, the same. Along with microbiologist Shirin Moossavi and colleagues, epidemiologist Meghan Azad of the University of Manitoba in Winnipeg, Canada, found two main differences between the mothers’ milk. Milk from women who pumped had more of the bacteria that can cause infections under the right conditions. It also had fewer bifidobacteria, which are generally thought to be beneficial. It’s too soon to say whether these bacterial differences are good or bad for infant health — or completely irrelevant. “We just show they are different,” Azad says.
4-1-19 We may have bred with Denisovans much more recently than we thought
Our species may have been interbreeding with Denisovans as recently as 15,000 years ago, according to a detailed analysis of the DNA of people living in Indonesia and Papua New Guinea. We already know that, after Homo sapiens first migrated out of Africa, our species repeatedly interbred with a number of now-extinct hominin species, including the Neanderthals and Denisovans. The signs are in our DNA today – all people of non-African descent carry some Neanderthal DNA, while some Asian people also have Denisovan DNA. Not much is known about the mysterious Denisovans. Their only physical remnants discovered so far are a few teeth and fragments of bone unearthed in a cave in Siberia. But DNA analyses have found that the Denisovans must have lived much further east and south of Siberia too. Genetic evidence suggested our species interbred with Denisovans at least twice, in Asia and Australasia, and that the genomes of people from Papua New Guinea may be up to 5 per cent Denisovan. Until now, such genetic studies have generally looked at only a small fraction of people’s DNA to draw these conclusions. To get a fuller picture, Murray Cox of Massey University, New Zealand, and his colleagues have done the first large-scale study of whole genomes from people living in Indonesia and Papua New Guinea, sequencing all the DNA of 161 different people. This reveals that our ancestors in this part of the world seem to have interbred with at least two distinct groups of Denisovans – one group about 50,000 years ago, as previously thought, and a second group much more recently. (Webmaster's comment: Many if not most human males will attempt to breed with anything that has a hole in it, including fence posts! If there was a human shaped creature around with a hole in it human males would certainly have tried breeding with it!)
4-1-19 Incredible fossil find may be first victims of dino-killer asteroid
A remarkable fossil deposit found in North Dakota seems to offer an unprecedented record of the mass extinction that wiped out most of the dinosaurs 66 million years ago. The fossils appear to be animals that were killed within minutes of an asteroid striking Earth, in a flood triggered by the shattering impact. “I have never seen a site like it,” says palaeontologist Phil Manning of the University of Manchester, UK, a member of the team studying the fossils. “You can almost see the event happening.” The findings were made public last week by the New Yorker magazine, rather than a traditional scientific paper. This has led many palaeontologists to be publicly sceptical of both the work and the researchers behind it. However, a paper has now been published in the Proceedings of the National Academy of Sciences (PNAS) journal and researchers are expressing cautious enthusiasm. The mass extinction 66 million years ago wiped out a swathe of species. Contrary to popular belief, it didn’t obliterate the dinosaurs: birds are a kind of dinosaur and they are still around. However, no non-avian dinosaurs survived. The extinction allowed mammals to flourish, paving the way for the evolution of primates and ultimately humans. The main cause seems to have been a 10-kilometre-wide asteroid that slammed into what is now Chicxulub on the Yucatán Peninsula in Mexico. The immediate blast was devastating, but the explosion also led to years of cold weather because so much dust was thrown up into the air, blocking sunlight. However, there were also huge volcanic eruptions in what is now India, which may also have contributed to the extinction. The asteroid impact would have sent powerful vibrations hurtling through the planet, causing widespread earthquakes and floods. The fossil deposit at the centre of the controversy preserves the site of a river, which would have experienced a flash flood as water hurtled inland. It is a mix of mud and sand that contains a densely packed collection of fossilised fish and other organisms. Everything seems to have been laid down in a single flood.
4-1-19 In ‘The Perfect Predator,’ viruses vanquish a deadly superbug
A scientist recounts the battle to save her husband from an antibiotic-resistant infection. Epidemiologist Steffanie Strathdee and her husband, Thomas Patterson, went to Egypt in 2015 expecting to come home with some photos and souvenirs. Instead, Patterson was hit with his own version of the 10 plagues. At first, doctors in Egypt thought Patterson had pancreatitis. But his health worsened after treatment, and he started hallucinating. Once flown to Germany, he was diagnosed with a multidrug-resistant bacterial infection in his pancreas. He was then airlifted to a hospital at Strathdee’s home institution, the University of California, San Diego. There, Patterson suffered several episodes of septic shock and spent months in a coma. The Perfect Predator chronicles the couple’s encounter with a bacterium that was resistant to every available antibiotic, and the rush to find an alternative treatment to save Patterson’s life. During the ordeal, Strathdee used her scientific training to research solutions and stumbled upon phage therapy. The idea is that even the most resistant bacteria can be defeated by their natural predators, viruses called bacteriophages. The nearly century-old treatment had been all but forgotten in the United States, in large part because of the invention of antibiotics, but was being used in parts of the former Soviet Union. Doctors needed the right phage, one capable of parasitizing the bacteria infecting Patterson. So Strathdee asked a team of scientists to drop everything and check their phage collections while also hunting for environmental samples for a virus that could be turned into an experimental treatment. Within three weeks, two sets of researchers found phages that were a match. Patterson was treated successfully, and the first phage therapy center in the United States opened last year at UC San Diego.