Culture

Research published in the journal BMC Evolutionary Biology has shed new light on why some grey squirrels are black.

The study was led by Dr Helen McRobie of Anglia Ruskin University (ARU), who has previously mapped the spread of black squirrels across the UK. Black squirrels are the same species as grey squirrels, with the only difference being their fur colour.

The new work builds on Dr McRobie's research from 2014, which found that the black fur is caused by the grey squirrel having a pigment gene with a missing piece of DNA.

Working with colleagues from the University of Cambridge and the Virginia Museum of Natural History in the United States, Dr McRobie has found that the faulty pigment gene in grey squirrels is identical to a faulty gene found in the closely-related fox squirrel, a species which is native to North America and also has black variants.

Testing DNA from grey and fox squirrels found across the United States and British Columbia, Canada, the researchers discovered that other "signatures" on the mutated gene are more closely related to the fox squirrel. This suggests it is highly likely the mutation first arose in the fox squirrel and passed to the grey squirrel through interbreeding.

Dr McRobie, Senior Lecturer in Biomedical Science at Anglia Ruskin University (ARU), said: "Squirrels take part in 'mating chases' where a female squirrel is pursued by lots of male squirrels and eventually one male mates with the female.

"People have spotted 'mixed species' mating chases, with a mix of grey and fox squirrels pursing a female. The most likely explanation for the black version of the gene being found in the grey squirrel is that a male black fox squirrel mated with a female grey squirrel.

"The fact black grey squirrels have become so common right across North America is possibly because black fur offers a thermal advantage, helping them inhabit regions with extremely cold winters. This may have contributed to the expansion of the grey squirrel's range during the past 11,000 years, following the end of the most recent ice age, helping them spread further north into Canada."

The black squirrels living in the UK are believed to have escaped from a private zoo, having been imported from the United States. The first wild black squirrel was recorded in Woburn, Bedfordshire, in 1912, and they are now found across many parts of South East England.

The pain-relieving effect of salicylic acid, now sold as Aspirin, has been known for thousands of years. Besides being a useful drug with numerous health applications, it is a stress hormone made by plants which is essential in enabling them to fight off damaging pathogens. What was not known, however, is how plants generated this hormone. Now, an international research team led by the University of Göttingen with the University of British Columbia in Vancouver have at last unravelled the biosynthesis of this crucial hormone. Their results were published in Science.

As far back as Neanderthal times, bark containing salicylic acid was chewed to self-medicate; the first chemical extraction was in the 1820s, and an improved version has been marketed as Aspirin for over 120 years. But no-one understood how plants actually made it. Then, 20 years ago researchers using the plant Arabidopsis thaliana discovered the first gene involved in salicylic acid synthesis. Ever since, countless groups have tried to identify the missing steps on the way to salicylic acid.

Dmitrij Rekhter and colleagues from the Department of Plant Biochemistry at the University of Göttingen found a way to investigate. They used special Arabidopsis plants isolated by Professor Zhang's team at the University of British Columbia, which have extremely elevated levels of salicylic acid. Then the researchers found that the precursor to salicylic acid accumulates in these plants if a gene of previously unknown function (PBS3) is removed. The team in Göttingen was therefore able to deduce the action of the gene product.

As first author Rekhter explains, "PBS3 attaches isochorismic acid to glutamic acid resulting in the formation of the previously unknown compound isochorismate-9-glutamate. This highly unstable substance decomposes spontaneously into salicylic acid and by-product." Solving the riddle of how plants biosynthesise salicylic acid was a joint effort of the teams of Professor Ivo Feußner, Dr Marcel Wiermer and Professor Volker Lipka at the University of Göttingen together with the team of Professor Yuelin Zhang at the University of British Columbia in Vancouver, within the International Research Training Group "PRoTECT".

Furthermore, it looks like this pathway applies across the plant kingdom. Feußner from the Department of Plant Biochemistry at the University of Göttingen says, "This research not only increases our understanding of how plants synthesise this hormone, but also opens up new opportunities to breed crops that are more resistant to disease. The important role of salicylic acid for plants in their battle against disease make these findings of fundamental importance for research areas such as plant immunity and therefore also food production."

OAK BROOK, Ill. - A drug used to treat attention-deficit/hyperactivity disorder (ADHD) appears to affect the development of the brain's signal-carrying white matter in children with the disorder, according to a study published in the journal Radiology. The same effects were not found in adults with ADHD.

Methylphenidate (MPH), sold under trade names including Ritalin and Concerta, is a commonly prescribed treatment for ADHD that is effective in up to 80 percent of patients. However, not much is known about its effect on the development of the brain, including the brain's white matter, which is important for learning and brain functions and coordinating communication between different brain regions.

To find out more about MPH's effects on white matter development, Dutch researchers performed a study of 50 boys and 49 young adult men diagnosed with ADHD. All patients were medication-naïve; that is, they had never received MPH prior to the study.

"Previous studies all have tried to statistically control for the effects of ADHD medications," said study senior author Liesbeth Reneman, M.D., Ph.D., from the Department of Radiology and Nuclear Medicine at the Academic Medical Center, University of Amsterdam, the Netherlands. "But we are the first to study medication-naïve patients in this context, which, of course, is crucial if you want to know how ADHD medications affect the developing brain."

Patients received either MPH or a placebo for 16 weeks. Before and one week after treatment cessation, the participants underwent MRI including diffusion tensor imaging (DTI), a technique that helps assess white matter. DTI provides a measure called fractional anisotropy (FA), which is thought to reflect important aspects of white matter such as nerve fiber density, size and myelination--the process of coating nerve fibers to protect the nerve and help it carry signals more efficiently.

In boys with ADHD, four months of treatment with MPH was associated with increased white matter FA. The effects were age dependent, as they were not observed in adults treated with MPH.

"The results show that ADHD medications can have different effects on the development of brain structure in children versus adults," Dr. Reneman said. "In adult men with ADHD, and both boys and adult men receiving placebo, changes in FA measures were not present, suggesting that the effects of methylphenidate on brain white matter are modulated by age."

Dr. Reneman and colleagues are studying the long-term implications of these findings on ADHD behavior, which have yet to be established. Many ADHD patients are on medications for years, so the long-term effects of MPH treatment represent a vital area of research. In the meantime, the researchers want to see tighter regulations for prescribing ADHD medications, since MPH is being prescribed not only to increasing numbers of children, but also at younger ages.

"What our data already underscore is that the use of ADHD medications in children must be carefully considered until more is known about the long-term consequences of prescribing methylphenidate at a young age," Dr. Reneman said. "The drug should only be prescribed to children who actually have ADHD and are significantly affected by it."

According to the Center for Disease Control and Prevention, based on parent reporting, approximately 5.2 percent of American children between the ages of 2 and 17 take ADHD medication.

A team of scientists from the University of Southampton, Bangor University and the National Oceanography Centre have discovered several artificially introduced species in the coastal waters of southern England, using a technique that could help the early detection of non-native species if adopted more widely.

Among the species identified during the study was Cephalothrix simula, a worm, originating from the North West Pacific Ocean, which contains neurotoxins that are potentially fatal if they enter the human body.

The researchers, led by Luke Holman, a PhD student at the University of Southampton, collected water and sediment from four marinas around the UK and analysed the DNA of each sample to determine which species had been present in the ecosystems.

Organisms leave traces of their DNA in water systems through a variety of means, for example fish can lose scales and many species can release sperm or eggs during the spawning season. The team were able to extract this genetic material, known as environmental DNA (eDNA), and compare it to global DNA databases to identify the presence of species.

Luke Holman said "We are enormously excited about the potential for eDNA in the detection of invasive species. This initial work gives us confidence that the technique could be invaluable both for catching invasions early on and also for monitoring the success of eradication efforts."

There are many ways in which species that are not native to the UK arrive on our shores. They can be carried in ballast water tanks or on ship hulls from one international harbour to another, something especially common in places like Southampton. They can also hitch a lift on live fish stocks and oysters imported for British fish farms.

In total the team identified 18 non-indigenous species across the four sampled marinas - in Southampton Water, Anglesey, The Bristol Channel and the River Blackwater. The Cephalothrix simula worm had not been previously detected in the UK when this study was carried out in May 2017 although it was subsequently found in Cornwall the following year; a discovery which has been documented by the Centre for Environment, Fisheries and Aquaculture Science (Cefas). Other recently introduced species the researchers detected included Arcuatula senhousia (Asian date mussel) and another type of worm known as Paranais frici.

If not caught early, invasive species can have devastating effects on the country's native wildlife habitats. For example, Asian date mussels can alter sediment through the thread like cocoons they produce which weave together and change the seafloor from a muddy to a thick, sandy material. This in turn changes the creatures that inhabit the area.

Luke Holman added "We know that the muddy flats of Southampton water and the Solent area provide a great deal of food for foraging birds so we should be worried about any species with an ability to change the sediment."

eDNA metabarcoding surveys are increasingly common in biodiversity monitoring, but their use for the detection of invasive species remains limited and this study, published in the journal Scientific Reports, is the first of its kind in the UK.

The team hopes to build on their research by providing guidance for routine monitoring of non-indigenous species to natural resource agencies both in the UK and elsewhere.

In the human body the salt content of cells and their surrounding is regulated by sophisticated transport systems. Special channels in the cell membrane selectively permit salt ions to flow in and out of cells. A research team led by Professor Thomas Jentsch at the FMP and MDC has now identified the molecular components of a previously unknown ion channel.

The membranes that encase cells and cell organelles are normally impermeable for charged particles such as salt ions. But there are loopholes: Transmembrane proteins can form channels that pass ions. In most cases, such ion channels open or close on receiving a particular signal transmitted, for example, voltage or a signaling molecule. The channels are often specialized to allow only specific ions - such as chloride, potassium, or sodium - to pass.

A team led by Professor Thomas Jentsch from Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP) and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) has now identified a new transmembrane protein called TMEM206 as a new chloride ion channel. It is characterized by a so-far unique activation mechanism: When the pH level decreases in the cell environment, the channel opens and allows chloride, depending on the cell type, to flow out or into the cell. This type of ion channels may play a role in the development of heart attacks, strokes, and tumors, for these diseases are accompanied by an acidification in the affected tissue.

The starting point for the current research was an ion channel called ASOR (Acid-Sensitive Outwardly Rectifying anion channel). More than ten years ago, electrophysiological studies had detected and characterized pH-regulated chloride currents in cells of various vertebrates. "But the structure of the underlying channel had remained unknown. Back then, technology had not been advanced enough to perform a genome-wide screen to identify it. We have now discovered the gene encoding the protein that forms the ASOR channel," explains Professor Thomas Jentsch, head of the research group on Physiology and Pathology of Ion Transport at the MDC and FMP.

It took about four years to complete the study. Many methods had to be adapted or newly developed. For example, the team devised a special optical detection assay for the function of the ASOR channel that is compatible with high-throughput methods.

In order to search for DNA sequences relevant to the ASOR channel, the researchers performed a siRNA screen. This involves using small pieces of RNA (small interfering RNA, or siRNA) to systematically shut down genes one by one in cultured cells and then analyzing the functional consequences.

They also employed CRISPR-Cas9 technology and mutations changing channel properties to confirm that the thus identified gene was in fact coding for the channel. "For us, it was extremely helpful that the Screening Unit at the FMP, which has a facility specializing in these high-throughput methods, was our direct neighbor," says Jentsch. "There are numerous robots there that pipette the samples, and it is equipped with automated cell culture systems." The Screening Unit's siRNA library contains siRNAs for all 20,000 human genes, each of which must be evaluated separately. To be on the safe side, three runs were performed so that in the end a total of 60,000 individual results had to be analyzed bioinformatically.

"The identification of TMEM206 as central component of the ASOR channel is a major breakthrough. This opens the door to finally uncover the currently unknown physiological roles of the channel," summarizes Jentsch. Chloride ions are among the most important and prevalent electrolytes in the body. Their concentration can vary substantially between the extracellular space, the cytoplasm, and various intracellular organelles. The cell membrane forms a barrier for the negatively charged chloride, but special membrane proteins enable it to cross this barrier. Chloride ions either move along concentration gradients through channels or, by coupling to other ions, can be actively pumped across the membrane by transporter proteins. Chloride channels carry out very diverse biological functions. The underlying proteins are also molecularly very diverse. They are regulated in a host of ways to regulate the transport of chloride according to the need of the cell and the organism.

There is strong evidence that the ASOR channel plays a role in acid-induced cell death. The channel allows the passage of chloride ions only when the extracellular milieu is very acidic. Even though the channel is found in every mammalian cell, this occurs only in a few specialized cell types or under pathological conditions such as stroke or heart attack or within tumors. However, the fact that ASOR plays a harmful role in disease does not explain why it is found in all mammalian cells.

There are still many unanswered questions, says Jentsch. What is the significance of the strong pH-dependence of the channel? Why do all cells apparently have this ASOR channel? And where exactly is the channel located inside the cells? Is it also present in acidic organelles, such as lysosomes and endosomes? In order to further elucidate the structure and physiological functions of ASOR, the research group has developed antibodies against TMEM206 and are generating mice in which the gene for the channel is destroyed. They want to find out in which cell the channel protein is expressed and where exactly it is localized within the cells. In the future, they also hope to clarify the physiological function by using their mouse models.

A new study analyzing samples from patients with and without acute flaccid myelitis (AFM) provides additional evidence for an association between the rare but often serious condition that causes muscle weakness and paralysis, and infection with non-polio enteroviruses. The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, funded the research, which was conducted by investigators at Columbia University's Center for Infection and Immunity and investigators from the Centers for Disease Control and Prevention. The findings are reported in the online journal mBio.

There have been 570 confirmed cases since CDC began tracking AFM in August 2014. AFM outbreaks were reported to the CDC in 2014, 2016 and 2018. AFM affects the spinal cord and is characterized by the sudden onset of muscle weakness in one or more limbs. Spikes in AFM cases, primarily in children, have coincided in time and location with outbreaks of EV-D68 and a related enterovirus, EV-A71. Both of these viruses typically cause mild respiratory illness from which most people recover fully. Despite the epidemiological link between enterovirus circulation and AFM cases, evidence of direct causality has not been found.

The researchers first looked for direct evidence of enterovirus infection in the cerebrospinal fluid (CSF) of 13 children and one adult diagnosed with AFM in 2018. They also examined five CSF samples taken from people with other central nervous system diseases. The team used a new tool they developed called VirCapSeq-VERT, which can detect any viral genetic material that is at least 60% like that of any known vertebrate virus. They found enteroviral genetic material (EV-A71) in only the one adult AFM case and genetic material from another enterovirus (echovirus 25) in one of the non-AFM cases.

The investigators also sought indirect evidence of enterovirus infection by looking for antibodies to enteroviruses made by the immune system in response to an infection. The team developed a microchip assay, AFM-SeroChip-1, that detects the presence of antibodies generated in response to any human enterovirus (EV-A, EV-B, EV-C or EV-D) infection. Using this assay, the team tested the same 14 CSF samples from the AFM patients. They also tested CSF samples taken from 11 adults with central nervous system conditions, such as multiple sclerosis, and from 10 children with Kawasaki disease, none of whom had AFM.

EV-specific antibodies were detected in the CSF of 79% (11 of 14) of the AFM cases. Of those, six samples were positive for EV-D68, strongly indicating that enterovirus had been in the central nervous system, even though it had not been detected by VirCapSeq-VERT. None of the CSF samples from children with Kawasaki disease had antibodies that reacted with any enterovirus.

While other etiologies of AFM continue to be investigated, this study provides further evidence that enterovirus infection may be a factor in AFM. In the absence of direct detection of a pathogen, antibody evidence of pathogen exposure within the central nervous system can be an important indicator of the underlying cause of disease, the researchers note.

NEW YORK, August 13, 2019 -- Exposure to violence, social conflict, and other stressors increase risk for psychiatric conditions such as depression and post-traumatic stress disorder. Not everyone who experiences significant stress will develop such a response, however, and the cellular and molecular basis for an individual's underlying resilience or susceptibility to stressful events has remained poorly understood. Now, a newly published paper in the journal eLife from researchers at the Advanced Science Research Center (ASRC) at The Graduate Center, CUNY suggests that the behavior of oligodendrocytes -- the glial cells that produce the myelin sheath that protects nerve fibers -- plays a critical role in determining whether we succumb to or tolerate stress.

"Through our study, we were able to identify brain-region-specific differences in the number of mature oligodendrocytes and in the content of myelin between two groups of mice who were categorized based on their resilience or susceptibility to an identical social-defeat stressor," said the paper's corresponding author Jia Liu, a research associate professor with the ASRC's Neuroscience Initiative. "After repeated exposure to an aggressive mouse, some animals, called "susceptible," avoided any sort of social interaction with their peers, while others remained resilient and continued to be socially engaged."

In follow-up brain tissue analysis, the research team detected fewer mature oligodendrocytes and irregular myelin coverage in the medial prefrontal cortex -- a brain region that plays a critical role in emotional and cognitive processing -- in the susceptible mice. In contrast, healthy numbers of oligodendrocytes and myelin were detected in resilient mice.

Methodology

For the study, researchers exposed test mice to an aggressor for five minutes daily over 10 days. Following this period, the mice were placed in the presense of unfamiliar mouse and categorized either as susceptible if they showed signs of social withdrawal or resilient if they still showed interest in socializing with the new mouse -- a social behavior that is typically detected in normal mice.

Reseachers next sought to determine if there were myelination differences between susceptible and resilient mice. They looked at two areas of the brain that are known to play a critical role in determining the individual's response to stress. In one of those areas -- the medial prefrontal cortex -- they found that the myelinated segments of nerve fiber in susceptible mice were shorter in length and thinner than typical. They did not find this condition in the resilient or control mice groups. They also investigated the state of each mouse group's glial cells, and discovered that in susceptible mice fewer of these cells had differentiated into myelin-producing oligodendrocytes.

In a final experiment, researchers found that induced damage to the myelin in the medial prefrontal cortex caused altered social behavior in mice, but the behavior returned to normal when new myelin was formed.

"Dr. Liu's research has highlighted the importance of stressful social events in changing the epigenetic code of oligodendrocyte progenitors, which may account for the increased susceptibility to developing chronic psychiatric disorders in some individuals," said Patrizia Casaccia, founding director of the ASRC Neuroscience Initiative. "Her data suggest that oligodendrocyte progenitor differentiation can be affected by emotional and psychological events, and this provides a new concept for preventing and treating depression. Current treatments target neuronal function, but Dr. Liu's work identifies potential new therapy targets as it suggests glial cell dysfunction could be a cause of stress-related mental disorders."

Sufferers of recurring urinary tract infections (UTIs) could expect more effective treatments thanks to University of Queensland-led research.

UTIs are one of the most common bacterial infections according to Professor Mark Schembri from UQ's School of Chemistry and Molecular Biosciences.

"They're a major burden on global healthcare," he said.

"Approximately 25 per cent of women who suffer UTI will experience recurrent UTI within six months of initial infection.

"It's a problem magnified by increasing antibiotic resistance - antibiotic treatments can sometimes just stop working on these patients, with dire results."

The study, performed in collaboration with researchers from the University of Utah, followed a long-term recurrent UTI sufferer, using genetic analysis to find out whether the infection came from a single bacterial 'reservoir' in the body.

"The patient we examined has suffered from recurring UTIs for 45 years, since 1974," Professor Schembri said.

"The longest period she can recall being UTI-free is nine months.

"During that time she's taken almost every type of antibiotic and the same bacteria has been able to survive and escape treatment, even when the patient used some of the strongest antibiotics available in our armoury."

The research team isolated E. coli from the patient's urine during repeat infections and determined its entire DNA sequence.

UQ's Associate Professor Scott Beatson said the analysis showed the bacteria causing recurring UTIs were identical.

"This was proof - her infections did indeed originate from a common reservoir," he said.

"To find the reservoir, we also collected and sequenced the DNA of E. coli recovered from the patient's faecal samples.

"These E. coli were the same as those that caused the recurring UTI, proving that the woman had a persistent reservoir of E. coli residing in her intestine - the source of her infections.

"We now know that bacteria can reside in the intestine for very long periods and cause recurring UTIs, despite antibiotic treatment.

"Therefore, it's time we consider using antibiotics that will not just treat the UTI in the bladder, but also eliminate the infection reservoir in the intestine that seeds recurrent infection of the bladder."

The paper's first author, UQ's Dr Brian Forde, said when a patient suffered a UTI episode, a faecal sample could determine if the infecting strain also resided in the intestine, by combining bacterial culture with genome sequencing technology.

"If the same strain keeps being identified, we could design tailored treatment to eliminate the bacteria from not just the patient's urine, but also the intestinal reservoir," he said.

"We predict a treatment like this would lead to reduced incidences of recurring UTI in patients suffering from this debilitating, chronic disease for which there is currently no effective cure." Professor Schembri said.

Deforestation in Colombia has been linked to armed conflict and forests' proximity to coca crops, the plant from which cocaine is derived.

A University of Queensland-led study found that conflict between illegal groups and the governmental military forces, proximity to coca plantations, mining concessions, oil wells and roads were all associated with increased deforestation.

UQ PhD student Pablo Negret said the study identified how local drivers of deforestation in tropical countries affect deforestation risk.

"The relationship between conflict and deforestation is far from simple," he said.

"Many factors interact to increase or decrease deforestation risk, but stable governance can help forest retention."

Mr Negret said establishing governmental control where Colombia's largest dissident group, the Revolutionary Armed Forces of Colombia (FARC), was present was essential to avoiding further deforestation.

"We need clear policy and action to stop the uncontrolled deforestation that has occurred since the official peace treaty between the Colombian Government and FARC was signed in 2016.

"Our research shows that conservation projects need to work in parallel with social projects and substituting illegal coca crops.

"One way to do this is to work with the communities in Indigenous reserves and Afro-Colombian collective lands to reach conservation objectives, while fostering economic activity."

The researchers used forest cover information collected from satellites between 2000 and 2015, analysing the association of 17 variables with deforestation patterns in the country.

Fellow study author Professor Martine Maron said by determining the drivers of deforestation the study could help prompt action to save at-risk forests.

"We must stop the full-scale destruction of the world's forests if we are to control the biodiversity and climate crisis," she said.

"And by teasing out the complex factors that threaten forests in a country like Colombia, we may be able to find effective solutions for addressing social and environmental ills across the globe.

"Peace and sustainability make good bedfellows."

The existing astronomical observatories on Maunakea returned to operations this weekend, and it didn't take long for a significant result to be achieved, not only for science, but for assuring the safety of the Earth.

Observations of the near-Earth asteroid 2006 QV89 made on August 11 with the Canada-France-Hawaii Telescope (CFHT) have ruled out any potential future impact threat to the Earth by this asteroid for the next century.

2006 QV89 was discovered on August 29, 2006, with a telescope in Arizona, and observations were only possible through September 8, 2006, when the asteroid became unobservable from telescopes on Earth. The orbit determined from these limited observations had significant uncertainty, and it was not possible to rule out the low probability of the asteroid impacting Earth in the future, possibly as early as 2019. Last month, observations with the European Southern Observatory's Very Large Telescope (VLT) in Chile did not find the asteroid where it would have appeared if it was on a trajectory that would impact Earth this September. This ruled out an impact in 2019, but an impact for 2020 remained a possibility, along with nearly two dozen more over the next hundred years, with eight of those in the next decade.

"There is a big difference between knowing where a hazardous asteroid isn't, and knowing where it is," said David Tholen, astronomer at the University of Hawai'i's Institute for Astronomy, who led the effort to recover 2006 QV89.

This summer provided the first clear opportunity to recover the asteroid since its discovery, but the uncertainty in its position on the sky spanned roughly 30 degrees (60 times the diameter of the moon) in mid-July, growing even larger as the asteroid approached the Earth. "That made the use of a large telescope with a wide-field camera absolutely essential," noted Tholen. Only a fraction of that uncertainty region had been imaged with CFHT on July 14, but operations at the existing telescopes were suspended on July 16, due to the protest on Maunakea.

"We found at least a dozen asteroids in the July 14 data that fell close to the region where 2006 QV89 could have been, but the suspension of operations prevented us from confirming which, if any, of those objects was 2006 QV89," said Tholen.

With access to the Maunakea telescopes blocked, Tholen enlisted the aid of Marco Micheli of the European Space Agency's NEO Coordination Centre in Frascati, Italy. Micheli is a UH graduate who led the effort to rule out the 2019 impact scenario with ESO's VLT. He pointed a telescope in Spain at the position for the best of the candidate objects, but after two hours of data collection, the object at the predicted position could not be convincingly distinguished from electronic noise in the data. It came as a great relief to learn that CFHT would resume operations last weekend.

"Our highest priority target for Saturday night was the best 2006 QV89 candidate, and despite some thin cirrus clouds and a lot of moonlight, we needed only four minutes of data to obtain proof that we had found the right object," said Tholen.

The International Astronomical Union's Minor Planet Center announced the recovery to the world on Sunday, and the impact monitoring services at the Jet Propulsion Laboratory and the University of Pisa/SpaceDys in Italy immediately began crunching the numbers to update the impact predictions. A little over an hour later, Davide Farnocchia of Center of Near-Earth Object Studies at NASA's Jet Propulsion Laboratory in Pasadena reported that all the impact scenarios for the next century had been eliminated.

"This result is only one example of the telescopes on Maunakea protecting Earth by observing and studying the asteroids that enter Earth's neighborhood," said Kelly Fast, manager of the Near Earth Object Observations Program in NASA's Planetary Defense Coordination Office, which supported the observations.

Much in the same way that meteorologists use weather satellite imagery to track hurricanes to determine whether they represent a hazard to people and property, astronomers use telescopes to track asteroids near the Earth to determine whether they represent an impact hazard. "A different asteroid, 2019 NX5, got away from us while the Maunakea telescopes were shuttered, which is regrettable," Tholen said. "We are relieved that we were able to catch 2006 QV89 before our window closed. We are even more relieved that it won't impact the Earth."

Philadelphia, August 13, 2019 - The maturation of skin microbial communities during childhood is important for the skin health of children and development of the immune system into adulthood, but only a few studies have analyzed the microbiota in young children. In a new study, investigators in China found that bacterial genera in children were more similar to those of their own mothers than to those of unrelated women. Their data suggest that the mode of delivery at birth could be an important factor in shaping the child's microbiome. They report their findings in the Journal of Investigative Dermatology, published by Elsevier.

"To date, research into the maternal influence on her child's skin microbiome has been mostly limited to a narrow postpartum window in children younger than one year old and fewer studies have explored the maternal relationship with the child's microflora after infancy," explained lead investigator Zhe-Xue Quan, Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Institute of Biodiversity Science, School of Life Sciences, Fudan University, Shanghai, China. "Therefore, we expanded the scope of our analysis to include sampling from different body sites and direct comparison to the mother of the child in order to provide novel insights."

Investigators examined the changes in the skin microbiota and analyzed relationships between the skin microbiome and microenvironment as well as between the microbiota composition of children and mothers in 158 children between one and ten years old. The mothers of 50 of these children were randomly selected and recruited to represent different child age groups. Microbiota structures between the children and their mothers were compared using 16S rRNA gene amplicon sequencing. Samples were taken from three skin sites: center of the cheek; one quarter of the length of the forearm from the hand; and the center of the calf. Data for 474 samples (three skin sites per child) were pooled into 36 groups according to age, gender, and skin site.

Sample location and age were the primary factors determining a child's skin bacterial composition, which differed significantly among the three sites. However, there was negative correlation between the abundances of Streptococcus and Granulicatella and age. The relative abundances of most bacterial genera in children were more similar to those of their own mothers than those of unrelated women. The facial bacterial composition of 10-year-old children was strongly associated with whether they were born by Caesarian section or vaginal delivery.

"By analyzing the microbial community structure at three very different skin sites of children, we demonstrated that the skin microbiome is strongly impacted by the surrounding microenvironment and that the alpha diversity of the skin microbiome increases during childhood," noted Professor Quan. "Our results suggest that the bacterial population on a child's skin is to a large extent similar to that of their mothers and is affected in the long term by the way they were delivered at birth. One possible explanation is that the developing skin microbiome interacts with the immune system, which may be educated by exposure to microbes during a critical window early in life. It means that microbial colonization runs in parallel with immune system development."

The skin serves as the body's first line of defense against environmental insult. It hosts approximately ten billion bacterial cells per 1.8 square meters. Skin-associated bacteria constitute a large proportion of the human microbiome and interact with the host immune system via numerous pathways. Depending on the skin microenvironment, certain bacteria can act as either beneficial microbes or opportunistic pathogens.

Researchers at EMBL's European Bioinformatics Institute (EMBL-EBI), the Babraham Institute and collaborators have used the epigenetic clock to explore the molecular mechanisms that may drive ageing in humans. They found one gene, called NSD1, that seems to be closely linked to the process. This type of research could advance our understanding of ageing.

There are different ways of measuring an organism's age. Chronological age is a measure of how long an organism has been alive, while biological age is a measure of how well the organism is functioning on a molecular level.

One useful tool for measuring biological age is the epigenetic clock, proposed first by Trey Ideker, and independently by Steve Horvath in 2013.

What is an epigenetic clock?

An epigenetic clock is a mathematical model that predicts age by measuring DNA methylation levels in different sites across the genome. DNA methylation is a process by which methyl groups are added to the DNA molecule, which can modify the function of a gene without changing its underlying DNA sequence. DNA methylation is essential for the healthy growth and development of cells and it is affected by lifestyle and environmental factors.

Epigenetic clocks can be used to estimate the biological age of a tissue, cell type or organ. By comparing 'DNA methylation age' or biological age with chronological age in different tissues, scientists can gain insights into how ageing works, the factors influencing it, and how ageing is linked to cancer, obesity, Alzheimer's disease and many other conditions.

A promising tool

The researchers examined different datasets - many of them publicly available - of people with developmental disorders, to see whether there were any associations between specific genes and an acceleration of biological age. They found that individuals with a mutation in gene NSD1 had an accelerated biological age according to the epigenetic clock, meaning they were ageing faster at a molecular level.

"The epigenetic clock is the most accurate tool available to measure the ageing process in humans," explains Daniel Elías Martín-Herranz, who recently completed his PhD at EMBL-EBI. "We wanted to 'peer inside' and better understand how it works. Specifically, we wanted to see if we could identify specific genes or proteins from the epigenetic machinery that accelerate or slow down the ageing process. The fact that we found one gene that, when mutated, results in a significant acceleration of biological age is very encouraging. It shows that the epigenetic clock is a promising tool for understanding ageing and that we may unravel the molecular mechanisms that control its ticking rate.

"There is a lot of potential for such studies, but it's also worth noting that they are not possible without access to relevant public datasets. We would like to thank our collaborators who made the data available to us."

Professor Wolf Reik from the Babraham Institute agrees. "Following on from the work with the mouse epigenetic ageing clock two years ago, this paper continues the productive collaboration between the Babraham Institute and EMBL-EBI on mammalian ageing," he says. "It's exciting to see that genes can be identified that may underlie an epigenetic ageing program and that they can make molecular sense. The gene identified here is implicated in ageing in other organisms, and in the regulation of the epigenome during the ageing process."

The RTS,S malaria vaccine could enhance the production of protective antibodies upon subsequent parasite infection, according to a study led by the Barcelona Institute for Global Health (ISGlobal), an institution supported by "la Caixa". The results, published in BMC Medicine, identify the antigens (or protein fragments) that could be included in future, more effective multivalent vaccines.

Immunity to a pathogen can be acquired by natural exposure to the microorganism or through vaccination. The mechanisms underlying both types of immunity are not always the same, particularly in the case of parasites with complex life cycles, such as Plasmodium falciparum, that causes malaria. Over the last few years, ISGlobal researcher Carlota Dobaño and her team have been investigating the immune response induced by the RTS,S, the most advanced malaria vaccine that will be tested at large scale in sub-Saharan Africa this year.

In this study, the authors investigated how vaccination affects natural immunity to the parasite upon subsequent exposure. "To date, most studies had focused on evaluating vaccine-specific responses but not responses towards other parasite antigens," explains Gemma Moncunill, last author of the study. The RTS,S vaccine contains one single parasitic antigen: a fragment of the CSP protein.

The research team analysed serum samples obtained from 195 children, vaccinated or not, who made part of the phase III RTS,S clinical trial and were followed up during 12 months. 78 were from Kintampo, Ghana, a region with high malaria transmission, and 115 were from Manhiça, Mozambique, where transmission is low to moderate. They studied the levels and type of antibodies recognising a total of 38 P. falciparum antigens, including the CSP protein, before and after vaccination.

They found three patterns of antibody responses to these antigens: those that decrease after vaccination, those that are unchanged, and those that increase. Many antibodies in the first group are considered markers of parasite exposure and were associated with a higher malaria risk. Those in the third group were associated with protection - they reduced by half the risk of developing the disease. These protective antibodies mostly recognised antigens expressed by parasite stages that circulate in the blood ant that infect red blood cells.

"We think that the partial efficacy of the vaccine allows low infection levels upon subsequent parasite exposure which in turn leads to the production of protective antibodies," explains Carlota Dobaño. "This effect would be observed especially in regions with low to moderate transmission levels," she adds. Importantly, these results identify antigens that could be included in future and more effective multivalent vaccines.

From not being able to cook to not liking the taste of vegetables - a new study from the University of East Anglia reveals why young men are not eating their 'five-a-day'.

A study published today in the journal Nutrients shows why British men aged 18-24 are struggling to eat even three portions of fruit and vegetables a day.

As well as not having the culinary skills to cook for themselves, the researchers found that young men are more focused on gaining muscle and improving their physique than eating a healthy diet.

Young men with the best diets had a more positive attitude towards healthy food, enjoyed preparing and eating a wide range of fruit and veg, and had a more holistic view of health and diet.

Lead researcher Dr Stephanie Howard Wilsher said: "In England about half of men eat less than three portions of fruit and veg a day, and young men aged 18-24 eat the least.

"This is really worrying because men are more likely than women to suffer health problems later in life such as coronary heart disease.

"We wanted to find out why many young men aren't eating their five-a-day, and also what motivates those who do."

The research team led focus groups involving 34 young men aged 18-24, who were of normal weight, in urban and rural areas in England. They used magazine images and health promotion materials as talking points to instigate discussions about health, diet and fitness.

The participants kept food diaries for four days, and were separated into groups of high consumers - who regularly ate more than four portions of fruit and veg a day, and low consumers - who managed less than three portions.

Dr Howard Wilsher said: "We found that the young men with the best diets really believed in their ability to afford, shop for, prepare and cook fruit and vegetables. These high consumers felt that they had good control of their diet and health, and had positive attitudes towards healthy food. For example they found that cooking and eating healthy food gave them enjoyment, satisfaction and better mood.

"They had a holistic view of health, liked the taste and variety of flavours in fruit and veg and they had learned to cook for themselves.

"Those who weren't eating enough either could or would not cook. For this group, convenience foods were easier and fruit and vegetables were viewed as expensive, not readily available and their preparation time-consuming.

"They had more negative attitudes such as not liking the taste of vegetables, and not finding fruit and veg very filling. Some weren't very open to trying new foods, and most didn't prioritise good health. They hoped they would stay healthy, even though many had close family members suffering from chronic health conditions. Low consumers were also more driven by social influences from friends, family, and social norms.

"Interestingly, both groups believed that fruit and vegetables benefitted health and were nutritious.

"But none of the young men were aware that eating fruit and vegetables could lower the risk of developing chronic health conditions such as diabetes and heart disease, however, low consumers didn't think too much about their future health and had a 'live for today' attitude.

"This research helps us understand the motivations of a hard-to-reach group, in order to develop and target diet and health interventions.

"Those who didn't eat much fruit and veg had a mistrust of health information. They thought that diet and health promotions should be better designed around their interests - such as sex, exercise and sports, with real examples of male health and fitness.

"Policy makers need to adopt different approaches to engage young men with health messages and improve their dietary choices."

DENVER/August 12, 2019 – Wild female Tasmanian devils have mating habits that could pose a challenge for conservationists trying to maintain genetic diversity in species recovery programs, found Morris Animal Foundation-funded researchers at the University of Sydney.

The research team discovered that Tasmanian devil females can be polyandrous, or have multiple mating partners, and their male partners can be younger than once thought. The team published their findings in the Biological Journal of the Linnean Society.

Devil facial tumor disease 1 (DFT1) and the recently discovered devil facial tumor 2 (DFT2) have decimated wild Tasmanian devil populations. Save the Tasmanian Devil Program, an initiative by the Tasmanian and Australian governments, was established to maintain an enduring, ecologically functional population of Tasmanian devils in the wild with a captive, insurance population of animals free from DFT1 and DFT2.

“The good news is that these devils may be changing their life history to adapt to life with the disease in their midst,” said Dr. Tracey Russell, biologist at the University of Sydney and lead author of the paper. “There are benefits to multiple paternity, including increased genetic diversity of offspring, but this may be problematic in a captive situation, where females have access to more than one male, making the parentage of the offspring unknown and needing to be determined.”

Multiple paternity of litters has been recorded in numerous marsupial species but had not been reported in Tasmanian devils. Dr. Russell’s team studied a population of devils on the Forestier Peninsula, in southeast Tasmania. Researchers extracted DNA from samples of each individual and compared those of the pups to those of potential fathers to identify sires.

The researchers discovered four out of the nine litters tested showed multiple siring of offspring. Even more interestingly, some of the sires were yearlings. Devils are thought to be sexually mature at 2 years old. While females have been observed to breed as yearlings in disease-ravaged areas, this is the first record of males doing so.

As this is a newly discovered phenomenon, it’s not yet known if multiple paternity increases offspring survival in the wild. However, in many species, polyandry offers potential benefits, such as reduced risk of male infanticide of offspring and increased genetic diversity of offspring.

DFTD1 and DFT2 are highly unique forms of transmissible cancers that are passed from one devil to another through biting, a common behavior that takes place during feeding and mating. Most infected Tasmanian devils die within three to six months of developing visible tumors. Primary tumors typically develop on the face or inside the mouth, and quickly grow into large tumors that metastasize to the internal organs.

When these cancers ravage a population, it is usually the older devils that succumb to the disease, since they tend to be the ones inflicting penetrating bites to each other. As the older devils die, younger devils are left without competition from larger males to breed with the females.

“This newly discovered potential adaptation is an important finding, in addition to efforts to find a cure for both diseases, as we seek to save the Tasmanian devil from extinction,” said Dr. Janet Patterson-Kane, Morris Animal Foundation Chief Scientific Officer. “The devils are in an evolutionary arms race with devil facial tumor disease and we continue to do all we can to increase their odds of success.”