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NATURE NONE SCI Science

Early humans gained height to survive in savannah

A comprehensive new study that looked at hominin fossils over a span of 4 million years suggests that early humans gained stature as they moved out of the forests and into the savannahs.

The study is published in the journal Royal Society Open Science.

The research, which is the largest-ever study of early human body sizes involving 311 specimens dating from the earliest upright species to modern humans, also found that early humans’ stature and weight increased at different speeds over time.

“An increase solely in stature would have created a leaner physique, with long legs and narrow hips and shoulders,” said lead author Dr. Manuel Will at the University of Cambridge’s Department of Archaeology and a Research Fellow at Gonville and Caius College, in a university statement. “This may have been an adaptation to new environments and endurance hunting, as early Homo species left the forests and moved to more arid African savannahs.”

Will explained that because a larger skin surface increases the ability to evaporate sweat, the higher surface-to-volume ratio of tall, lanky body would benefit the hunter forced to stalk animals for long hours in the arid heat.

“The later addition of body mass coincides with ever-increasing migrations into higher latitudes, where a bulkier body would be better suited for thermoregulation of colder Eurasian climates,” Will said.

While height increased dramatically between 1.4 and 1.6 million years ago, consistently heavier hominins do not appear in the fossil record until about a million years later.

“From then onwards, average body height and weight stays more or less the same in the hominin lineage, leading ultimately to ourselves,” added Will.

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HEALTH NATURE NONE SCI Science

Wounds heal quicker during the day, study reports

Wounds heal more quickly during the day than they do at night, a new study published in Science Translational Medicine reports.

This discovery comes from researchers at the UK’s MRC Laboratory of Molecular Biology, who found that burns sustained at night often take much longer to heal than ones sustained during the day. 

In the study, researchers examined 118 patients at NHS burn units. They then recorded what time of day the patients got their burns as well as how long the wounds took to heal. Burns that occurred at night took roughly 11 days longer — 28 compared to 17 — to get better.

Researchers explained this odd difference by looking at fibroblasts, the skin cells that rush to the site of injury to close up wounds. This revealed that the cells change their abilities depending on the time of day. While the sun is out, fibroblasts are primed to react to injury. However, they lose that ability at night.

“It is like the 100 meter,” study co-author John O’Neill, a researcher at the MRC Laboratory of Molecular Biology, told BBC News  “The sprinter down on the blocks, poised and ready to go, is always going to beat the guy going from a standing start.”

This finding is important because doctors could use the new information to improve surgery. That is because certain drugs — such as the steroid cortisol — can reset an individual cell’s body clock. As a result, it may help night-time procedures by making the body better at healing.

In addition, as every person’s internal clock runs differently, it may also be beneficial to schedule procedures in time with the patients’ 24-hour “circadian rhythms.”

However, such theories need to be tested before they are put into practice. Researchers plan to continue their research into this topic to see what else it could tell them about health.

“By taking these [circadian factors] into account, not only could novel drug targets be identified, but also the effectiveness of established therapies might be increased through changing what time of day they are given,” added John Blaikley, a clinician scientist at the University of Manchester.

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NATURE NONE SCI Science

EPA approves genetically-modified mosquitoes

The Environmental Protection Agency (EPA) has given MosquitoMate permission to use male mosquitoes infected with the bacteria Wolbachia pipientis to keep Asian tiger mosquito populations in check.

The agency first gave approval to the biotech company last Friday to release mosquitoes into the environment.

For the process, researchers first infect male mosquitoes — which do bit humans — with the bacteria. Then, when those males mate with wild female mosquitoes, the fertilized eggs to not hatch.

“It’s a non-chemical way of dealing with mosquitoes, so from that perspective, you’d think it would have a lot of appeal,” said David O’Brochta, an entomologist at the University of Maryland, according to Newsweek. “I’m glad to see it pushed forward, as I think it could be potentially really important.”

The new approval last five years and will go into effect for Washington, D.C., California, Connecticut, Delaware, Illinois, Indiana, Kentucky, Massachusetts, Maine, Maryland, Missouri, New Hampshire, New Jersey, Nevada, New York, Ohio, Pennsylvania, Rhode Island, Tennessee, Vermont, and West Virginia.

Scientists hope that, as more bacteria-infected males are released into the wild, the population of Asian tiger mosquitoes will decrease. Other insects and species of mosquitoes will not be harmed.

If the new method proves to be successful at fighting populations, there is a chance the company could begin to sell bacteria-infected mosquitoes next summer to both homeowners and larger municipalities. However, in order to do that, MosquitoMate would need to register in each individual state where the bugs are used.

This is the first time genetically modified mosquitoes will be distributed over such a large area. However, MosquitoMate has already tested the process on a different species of mosquito — known as Aedes aegypti — in the both the Florida Keys and Fresno, California. 

This technology is important because, if it proves to be successful on widespread levels, it could be a big step toward preventing mosquito-borne diseases across the world. The newest product targets insects that can spread a many different illnesses, including Zika, yellow fever, chikungunya, and dengue. While those issues are not prevalent in America, diseases like dengue affect 96 million people across the world.

“Over a very short period of time, the Wolbachia was able to invade the wild mosquito population until close to 100 percent of all mosquitoes had the Wolbachia infection — and so we presume, greatly reduced ability to transmit dengue between people,” Australian researcher Scott O’Neill told NPR.

These findings come from a report in the journal Nature.

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NATURE NONE SCI Science

Medical miracle: Gene therapy gives boy whole new skin

A seven-year-old boy suffering from a genetic disease that caused most of his outer skin layer to peel away has been saved by researchers who grew him a new skin using his own genetically modified stem cells.

An international team of researchers from Germany, Austria, and Italy report the results in the journal Nature.

The boy has a condition known as junctional epidermolysis bullosa (JEB), a form of a condition also known as butterfly disease. The debilitating disorder is the result of several mutations in proteins affecting the thin layer of skin between the epidermis and dermis.

The defect causes the skin to become very fragile, with resulting blisters and severe peeling that can leave mortal wounds and increase the risk of skin cancer.

“We got this kid transferred in summer 2015 from another tertiary care hospital,” explained Dr. Tobias Rothoeft at the Department of Neonatology and Pediatric Intensive Care of University Children’s Hospital at Ruhr University Bochum in Germany, in a press briefing, as reported by Medical News Today. “He was admitted there because he had developed an infection in which he rapidly lost nearly two-thirds of his body surface area.”

After several treatments failed, the medical team was ready to give up, feeling sure the boy would die. But then, after re-studying the literature, they approached Dr. Michele De Luca, a professor of biochemistry and director of the Centre for Regenerative Medicine “Stefano Ferrari” at the University of Modena and Reggio Emilia in Italy.

Dr. De Luca has spent his career developing therapies for skin and eye conditions. He assured Dr. Rothoeft that he could grow enough skin to heal the boy. To correct the boy’s genetic defect, De Luca and his team used a virus to insert a normal copy of the faulty gene into the cells.

After three operations and eight months in the intensive care unit the boy went home with 80 percent of body covered in brand-new skin.

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HEALTH NATURE NONE SCI Science

Painkillers just as effective as opioids, study reports

Simple, over-the-counter painkillers may be just as effective as opioids when it comes to fighting pain, new research published in the journal JAMA reports.

This new finding is important because America’s opioid epidemic continues to grow with each passing year. More than 500,000 people have died from drug overdoses since 2000, and opioids were the cause of a lot of those deaths. As a result, doctors have been attempting to find more effective ways to help patients deal with pain.

This study may provide an answer.

“The results did surprise me,” said study co-author Andrew Chang, a professor of emergency medicine at Albany Medical Center, according to TIME. “Most physicians reflexively give opioids to patients with fractures or broken bones. This study lends evidence that opioids aren’t always necessary even in the presence of fractures.”

 

In the study, researchers from the Albany Medical Center analyzed whether alternative painkillers could help treat pain in emergency rooms of hospitals. They looked at over 400 people who came to two different emergency rooms in the Bronx for strains, sprains, or fractures. Then, they randomly assigned either non opioid painkillers — a combination of ibuprofen and acetaminophen (Tylenol) — or one of three variations of opioid-based pain killers to the subjects.

After two hours, the doctors asked the subjects to rate their pain on an 11-point scale and compared the different responses. This showed that the generic pills did as much to quell pain as more advanced opioids.

This discovery is important because it could change the way doctors prescribe painkillers. Addiction is a serious problem, and it will only continue to grow unless something is done. Switching away from opioids could be a step in the right direction.

“Preventing new patients from becoming addicted to opioids may have a greater effect on the opioid epidemic than providing sustained treatment to patients already addicted,” Demetrios Kyriacou, an emergency medicine specialist at Northwestern University, wrote in an accompanying editorial, according to The Washington Post.

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HEALTH NATURE NONE SCI Science

Even light drinking can increase cancer risk, study reports

The American Society of Clinical Oncology (ASCO) reports that alcohol consumption heavily increases a person’s risk for cancer, according to a new study in the Journal of Oncology.

This discovery follows a survey that found 70 percent of Americans do not recognize drinking alcohol as a risk factor for cancer. That is concerning because alcohol consumption is known to increase the risk of several cancers, including head, neck, esophageal, liver, breast, and colorectal.

Alcohol is officially classified as a carcinogen by the International Agency for Cancer Research. Roughly 3.5 percent of all U.S. cancer deaths — roughly 19,500 deaths — are related to alcohol. While the greatest risks are linked to heavy, long-term use, even low alcohol consumption (defined as less than one drink per day) or moderate consumption (up to two drinks per day for men, and one drink per day for women) can increase risk.

In addition, researchers found that, among women, light drinkers have a four percent increased risk of breast cancer, while moderate drinkers have a 23 percent increased risk of the disease. Heavy drinkers who consume more than eight drinks a day have a 63 percent increased risk of breast cancer.

Both men and women who drink heavily have a much greater chance of head, neck, and oral cancers as well because those tissues come into direct contact with alcohol carcinogens.

“Alcohol consumption is one of the most difficult dietary factors to accurately ascertain,” Anne McTiernan, a cancer prevention researcher at the Fred Hutchinson Cancer Research Center in Seattle who was not involved in the study, told Reuters.”Most people don’t know how much they’ve drunk (in terms of ounces), or how much alcohol is in what they drink. And most don’t accurately recall how often they drink.” 

Researchers hopes to draw attention to the strong links between drinking alcohol and risks for several types of cancer. They hope studies such as this one could help more people understand the risks of drinking and perhaps lead to new policy changes as well.

“The more you drink, the higher the risk,” said Clifford A. Hudis, the chief executive of ASCO who was not involved in the research, according to The New York Times. “It’s a pretty linear dose-response.”

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NATURE NONE SCI Science

Dinosaur extinction may be the reason mammals are active during the day

Researchers from Tel Aviv University and University College London believe they have successfully traced the origins of humans diurnal lifestyle, and can explain why mammals tend to sleep at night.

Though most mammals have been going to sleep at night and waking up in the morning for hundreds of thousands of years, that was not always the case. Early species were first nocturnal, and then slowly became diurnal. Though nobody knows why this change occurred, the team in the study believes it is linked to the dinosaurs.

The first mammals evolved long before dinosaurs died off. However, the beasts likely had a large influence on the smaller creatures. As they were constantly under threat from being eaten, it would make sense that the first mammals hid during the day and only came out at night.

“We were very surprised to find such close correlation between the disappearance of dinosaurs and the beginning of daytime activity in mammals, but we found the same result unanimously using several alternative analyses,” said study co-author Roi Maor, a Ph.D. student at Tel Aviv University and University College London, in a statement.

In the study, the team used computer algorithms to look at 2,415 modern animal species and identify how they acted millions of years ago. By focusing on two different mammal family trees, researchers discovered that nearly all early species became active during the day shortly after the dinosaurs died off.

First, the species transitioned to activities that took place during both day and night. After a few millions of years, they completely made the transition.

The research also showed the mammals who would eventually turn into simian primates — a group that includes monkeys and apes — were the first to wake up during the day. That would help explain why simians have excellent day vision compared to other mammals.

However, while the study present compelling evidence, the team states that they cannot assume the fall of the dinosaurs directly led to the shift in sleeping patterns. It is likely, but more research needs to be done before such claims can be made.

“It’s very difficult to relate behavior changes in mammals that lived so long ago to ecological conditions at the time, so we can’t say that the dinosaurs dying out caused mammals to start being active in the daytime,” said study co-author Kate Jones, a researcher at University College London, according to Newsweek “However, we see a clear correlation in our findings.”

This research is published in the journal Nature Ecology & Evolution.

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NATURE NONE SCI Science

Fossils from earliest modern mammals uncovered in England

Researchers from Portsmouth University have uncovered fossils from the oldest-known ancestors of most living mammals in southern England, a new study in Acta Palaeontologica Polonica reports.

The 145-million-year-old teeth belonged to extinct shrew-like animals that existed during the time of the dinosaurs. The team in the study analyzed the remains and came to the conclusion that they are the earliest remains ever found from mammals in the line the eventually led to humans.

”Here we have discovered from the Jurassic coast a couple of shrew-like things that are to date unequivocally our earliest ancestors,” said lead author Steve Sweetman, a researcher at Portsmouth University, according to BBC News.

The ancient mammals were small, furry creatures that likely first existed under the cover of night. Scientists believe they burrowed through the ground and dined on both insects and plants. Their teeth could pierce, cut, and crush food — which made them quite advanced for their time — and they were also worn. That suggests the shrews lived during a time where they thrived.

Researchers first uncovered the fossils while sifting through rock samples collected at Durlston Bay near Swanage. They have named the species Durlstotherium newmani.

This study is important because it could help shed light on a long-debated topic and help researchers build a better evolutionary timeline. Recent discoveries have dated the earliest mammals to 160 million years ago, but molecular data has directly refuted such claims. The new findings could put that debate to rest.

The ancient animals are the second oldest placental mammals ever found, suggesting that there is still a lot to learn about evolution during the Jurassic and Cretaceous period.

“The Jurassic Coast is always unveiling fresh secrets and I’d like to think that similar discoveries will continue to be made right on our doorstep,” said study co-author Dave Martill, a Professor of Palaeobiology at the University of Portsmouth, according to The Guardian.

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HEALTH NATURE NONE SCI Science

Mumps cases on the rise, despite vaccines

Mumps is making a comeback — even among people who were vaccinated in childhood, according to the U.S. Centers for Disease Control and Prevention (CDC).

Last year, reported mumps cases in the United States totaled 6,000, the highest number in a decade. By comparison, in 2010, total annual cases numbered only in the hundreds.

The recent cases tend to occur in localized outbreaks among people between 18-22 years old.

“Mumps outbreaks are on the rise,” said Dr. Janell Routh, a pediatrician and medical officer on the CDC’s mumps team, as reported by The New York Times. “We’re seeing it in a young and highly vaccinated population.”

Mumps is a virus that causes painful swelling of the salivary glands under the ears, along with fever and fatigue. It can be spread by coughing and sneezing, sharing eating utensils, and living in close contact with a carrier.

While the mumps vaccine can weaken over time in some people, it still offers significant protection against serious complications, such as orchitis, an inflammation of the testicles in young males that can result in low sperm counts and decreased fertility.

During an outbreak of more than 450 cases of mumps at the University of Iowa and the surrounding area in 2015-16, the state health department decided to offer people a third dose of the vaccine.

“Should this situation occur again, we would give third dose,” said Dr. Patricia Quinlisk, the medical director and state epidemiologist of the Iowa Department of Public Health, in a recent article in The New England Journal of Medicine. “In our outbreak it did substantially decrease the risk of other students getting mumps, and was instrumental in stopping the outbreak.”

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NATURE NONE SCI Science

Hydrothermal conditions on Enceladus spark hope for presence of alien life

Saturn’s icy moon Enceladus has a warm liquid ocean that makes it especially intriguing to scientists looking for extraterrestrial life.

Now, a new study suggests that the moon’s wet gravelly core creates enough tidal friction to keep the ocean liquid for billions of years.

The study appears Nov. 6 in the journal Nature Astronomy.

Scientists from the University of Nantes looked at observations from the now-defunct Cassini spacecraft, which studied Saturn and its moons for 13 years.

“What we have in mind is not a sponge like porosity, it’s more like a pile of sand or gravel,” said co-author Gaël Choblet, in a report by Popular Mechanics.

When Cassini detected giant geysers shooting hundreds of miles into space from Enceladus’ south pole, scientists eventually concluded that a massive liquid ocean lurked beneath the moon’s surface.

While the north pole shows some indication of geologic activity, the south pole is much more active, according to Choblet. This is partly because the ice is much thicker at the north pole. In addition, the south pole has enough cracks in the ice to let water seep out into interstellar space.

“Where Enceladus gets the sustained power to remain active has always been a bit of a mystery, but we’ve now considered in greater detail how the structure and composition of the moon’s rocky core could play a key role in generating the necessary energy,” Choblet said, in a statement by the European Space Agency.

It will take future missions to analyze the organic molecules present in Enceladus’ water plumes before scientists know if the hydrothermal conditions on the moon have allowed life to take hold, according to Nicolas Altobelli, ESA’s Cassini project scientist.