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A study by UCLA psychologists provides strong evidence that a certain region of the brain plays a critical role in memory recall. The research, published in the Journal of Cognitive Neuroscience, also shows for the first time that using an electrical current to stimulate that region, the left rostrolateral prefrontal cortex, improves people's ability to retrieve memories.

"We found dramatically improved memory performance when we increased the excitability of this region," said Jesse Rissman, a UCLA assistant professor of psychology, and of psychiatry and biobehavioral sciences, the study's senior author.

The left rostrolateral prefrontal cortex is important for high-level thought, including monitoring and integrating information processed in other areas of the brain, Rissman said. This area is located behind the left side of the forehead, between the eyebrow and the hairline.

"We think this brain area is particularly important in accessing knowledge that you formed in the past and in making decisions about it," said Rissman, who also is a member of the UCLA Brain Research Institute.

The psychologists conducted experiments with three groups of people whose average age was 20. Each group contained 13 women and 11 men.

Participants were shown a series of 80 words on a computer screen. For each word, participants were instructed to either imagine either themselves or another person interacting with the word, depending on whether the words "self" or "other" also appeared on the screen. (For example, the combination of "gold" and "other" might prompt them to imagine a friend with a gold necklace.)

The following day, the participants returned to the laboratory for three tests -- one of their memory, one of their reasoning ability and one of their visual perception. Each participant wore a device that sent a weak electrical current through an electrode on the scalp to decrease or increase the excitability of neurons in the left rostrolateral prefrontal cortex. Increasing their excitability makes neurons more likely to fire, which enhances the connections between neurons, Rissman said.

(The technique, called transcranial direct current stimulation, or tDCS, gives most people a warm, mild tingling sensation for the first few minutes, said the study's lead author, Andrew Westphal, who conducted the study as a UCLA doctoral student and is now a postdoctoral scholar in neurology at UC San Francisco.)

For the first half of the hour-long study, all participants received "sham" stimulation -- meaning that the device was turned on just briefly, to give the sensation that something was happening, but then turned off so that no electrical stimulation was applied. This allowed the researchers to measure how well each participant performed the tasks under normal conditions. For the next 30 minutes, one group of participants received an electrical current that increased their neurons' excitability, the second group received current that suppressed neuron activity and the third group received only the sham stimulation. The researchers analyzed which group had the best recall of the words they saw the previous day.

First, the scientists noted that there were no differences among the three groups during the first half of the study -- when no brain stimulation was used -- so any differences in the second half of the experiment could be attributed to the stimulation, Westphal said.

Memory scores for the group whose neurons received excitatory stimulation during the second half of the study were 15.4 percentage points higher than their scores when they received the sham stimulation.

Scores for those who received fake stimulation during both sessions increased by only 2.6 percentage points from the first to the second session -- a statistically insignificant change that was likely was due to their increased familiarity with the task, according to the paper. And scores for the group whose neuron activity was temporarily suppressed increased by just five percentage points, which the authors also wrote was not statistically significant.

"Our previous neuroimaging studies showed the left rostrolateral prefrontal cortex is highly engaged during memory retrieval," Rissman said. "Now the fact that people do better on this memory task when we excite this region with electrical stimulation provides causal evidence that it contributes to the act of memory retrieval.

"We didn't expect the application of weak electrical brain stimulation would magically make their memories perfect, but the fact that their performance increased as much as it did is surprising and it's an encouraging sign that this method could potentially be used to boost people's memories."

The study's reasoning task asked participants to decide in seven seconds whether certain pairs of words were analogies. Half of the trials featured word pairs that were true analogies, such as "'moat' is to 'castle' as 'firewall' is to 'computer.'" (In both pairs, the first word protects the second from invasion.) The other half had word pairs that were related but not actually analogous.

Researchers found no significant differences in performance among the three groups.

For the final task, focusing on perception, subjects were asked to select which of four words has the most straight lines in its printed form. (One example: Among the words "symbol," "museum," "painter" and "energy," the word "museum" has the most straight lines.) Again, the researchers found no significant differences among the three groups -- which Rissman said was expected.

"We expected to find improvement in memory, and we did," Rissman said. "We also predicted the reasoning task might improve with the increased excitability, and it did not. We didn't think this brain region would be important for the perception task."

Why do people forget names and other words? Sometimes it's because they don't pay attention when they first hear or see it, so no memory is even formed. In those cases, the electrical stimulation wouldn't help. But in cases where a memory does form but is difficult to retrieve, the stimulation could help access it.

"The stimulation is helping people to access memories that they might otherwise have reported as forgotten," Westphal said.

Although tDCS devices are commercially available, Rissman advises against anyone trying it outside of supervised research.

"The science is still in an early stage," he said. "If you do this at home, you could stimulate your brain in a way that is unsafe, with too much current or for too long."

Rissman said other areas of the brain also play important roles in retrieving memories. Their future research will aim to better understand the contributions of each region, as well as the effects of brain stimulation on other kinds of memory tasks.

In ongoing research to find a treatment for acute kidney injury, Wake Forest Institute for Regenerative Medicine (WFIRM) scientists have further advanced a promising approach using therapeutic factors produced by stem cells by creating a more efficient delivery method that would improve tissue regeneration.

WFIRM researchers wanted to determine if any of the growth factors could lead to kidney function recovery. They developed a gel-based system that contained a cocktail of stem cell derived growth factors.

"The results indicate that stem cell-secreted factors can mitigate kidney injury, and a well-controlled delivery system is needed to achieve maximized and sustained beneficial outcomes," said James Yoo, M.D., Ph.D., lead author of the paper and a professor of regenerative medicine at WFIRM.

The study was released today in the journal Stem Cells Translational Medicine.

Increasing incidence of acute kidney injury is contributing to the global health burden of chronic kidney disease. More than 30 million American adults are affected by the disease and millions more are at risk of developing it, according to the National Kidney Foundation. The current management for kidney failure is dialysis or organ transplantation. One possible approach for the treatment of kidney injury is to regenerate damaged tissues using therapeutic cells and cellular products.

For this study, a pre-clinical model of kidney failure was created. To test the feasibility of the controlled delivery, stem cell-derived conditioned medium was physically encapsulated within the gel and the release of the biological factors was assessed.

WFIRM researchers injected the growth factor gel into the model and observed significant improvement of kidney function over seven days using blood analysis.

"We found that using a growth factor cocktail significantly enhanced cell proliferation and survival in vitro, leading to a more rapid functional recovery," said Sunil George, Ph.D., a WFIRM research fellow and co-author who has been a part of the studies.

Yoo said that future research will also help determine if stem cell-derived conditioned medium with a sustained and controlled delivery system can be developed as a therapy that could block the progression of acute kidney injury to chronic kidney disease.

PHILADELPHIA--Growing up in poverty and experiencing traumatic events like a bad accident or sexual assault can impact brain development and behavior in children and young adults. Low socioeconomic status (L-SES) and the experience of traumatic stressful events (TSEs) were linked to accelerated puberty and brain maturation, abnormal brain development, and greater mental health disorders, such as depression, anxiety, and psychosis, according to a new study published this week in JAMA Psychiatry. The research was conducted by a team from Perelman School of Medicine at the University of Pennsylvania and Children's Hospital of Philadelphia (CHOP) through the Lifespan Brain Institute (LiBI).

"The findings underscore the need to pay attention to the environment in which the child grows. Poverty and trauma have strong associations with behavior and brain development, and the effects are much more pervasive than previously believed," said the study's lead author Raquel E. Gur, MD, PhD, a professor of Psychiatry, Neurology, and Radiology at the Perelman School of Medicine at the University of Pennsylvania, and director of the Lifespan Brain Institute.

Parents and educators are split into opposing camps with regard to the question of how childhood adversity affects development into mature, healthy adulthood. Views differ from "spare the rod and spoil the child" to concerns that any stressful condition such as bullying will have a harmful and lasting effects. Psychologists and social scientists have documented lasting effects of growing up in poverty on cognitive functioning, and clinicians observed effects of childhood trauma on several disorders, though mostly in the context of post-traumatic stress disorders (PTSD). There are also anecdotal observations, supported by some research, that adversity accelerates maturation--children become young adults faster, physically and mentally. Neuroscientists, who are aware of the complexity of changes that the brain must undergo as it transitions from childhood to young adulthood, suspected, and more recently documented that childhood adversity affects important measures of brain structure and function. But this study was the first to compare the effects of poverty (L-SES) to those who experienced TSEs in the same sample set.

The researchers analyzed data from the Philadelphia Neurodevelopmental Cohort, which included 9,498 participants aged 8 to 21 years for the study. The racially and economically diverse cohort includes data on SES, TSEs, neurocognitive performance, and in a subsample, multimodal neuroimaging taken via MRI.

The researchers found specific associations of SES and TSE with psychiatric symptoms, cognitive performance, and several brain structure abnormalities.

The findings revealed that poverty was associated with small elevation in severity of psychiatric symptoms, including mood/anxiety, phobias, externalizing behavior (oppositional-defiant, conduct disorder, ADHD), and psychosis, as compared to individuals who did not experience poverty. The magnitude of the effects of TSEs on psychiatric symptom severity was unexpectedly large. TSEs were mostly associated with PTSD, but here the authors found that even a single TSE was associated with a moderate increase in severity for all psychiatric symptoms analyzed, and two or more TSEs showed large effect sizes, especially in mood/anxiety and in psychosis. Additionally, these effects were larger in females than in males.

With neurocognitive functioning, the case was reversed; poverty was found to be associated with moderate to large cognitive deficits, especially in executive functioning--abstraction and mental flexibility, attention, working memory--and in complex reasoning. TSEs were found to have very subtle effects, with individuals who experienced two or more TSEs showing a mild deficit in complex cognition, but demonstrating slightly better memory performance.

Both poverty and TSEs were associated with abnormalities across measures of brain anatomy, physiology, and connectivity. Poverty associations were widespread, whereas TSEs were associated with more focused differences in the limbic and fronto-parietal regions of the brain, which processes emotions, memory, executive functions and complex reasoning.

The researchers also found evidence that adversity is associated with earlier onset of puberty. Both poverty and experiencing TSEs are associated with the child physically maturing at an earlier age. The researchers also found the same effects on the brain, with findings revealing that a higher proportion of children who experienced adversity had characteristics of adult brains. This affects development, as the careful layering of the structural and functional connectivity in the brain requires time, and early maturity could prevent the necessary honing of skills.

"Altogether our study shows no evidence to support the 'spare the rod' approach, to the contrary we have seen unexpectedly strong effects of TSEs on psychiatric symptoms and of poverty on neurocognitive functioning, and both are associated with brain abnormalities," Gur said. "The study suggests that it makes sense for parents and anyone involved in raising a child to try and shield or protect the child from exposure to adversity. And for those dealing with children who were already exposed to adversity--as is sadly the case today with refugees around the world--expect an increase in symptoms and consider cognitive remediation, a type of rehabilitation treatment which aims to improve attention, memory, and other cognitive functions."

"Traumas that happen to young children can have lifelong consequences," said the study's senior author Ruben C. Gur, PhD, a professor of Psychiatry, Radiology, and Neurology, and director of the Brain Behavior Laboratory. "Obviously it would be best if we could ameliorate poverty and prevent traumatic events from occurring. Short of that, the study calls for paying more attention to a child's socioeconomic background and to effects of trauma exposure. Parents and educators should become more aware of the special needs of children who are exposed to either adversity. Additionally, mental health professionals should be particularly on notice that traumatic events are associated not only with PTSD, but with elevations across domains including mood, anxiety, and psychosis."

A new report in Science provides the first evidence of a mammal -- the highveld mole-rat -- being immune to pain from exposure to allyl isothiocyanate, or AITC, the active ingredient of wasabi.

The scientists who studied the animals say that understanding how these African rodents evolved to be insensitive to this specific type of pain could point to new directions for solving pain in humans.

"Mole-rats are extremely curious animals and we have been studying them at UIC for more than 20 years," said study co-author Thomas Park, professor of biological sciences at the University of Illinois at Chicago College of Liberal Arts and Sciences. "This new discovery -- that they have evolved to be insensitive to certain pain stimuli common in their environment -- is another example of the cool biological lessons to be learned from studying them."

Park worked alongside scientists from the Max Delbruck Center for Molecular Medicine in Berlin and the University of Pretoria in Pretoria, South Africa, on the study. The research was conducted at UIC and in South Africa.

They exposed the paws of eight species of mole-rats to three compounds that induce a pain-like response -- AITC, an acidic solution with a pH similar to lemon juice and capsaicin, the spicy ingredient in chili peppers. The scientists monitored behaviors, such as the time an animal spent licking its paws after being exposed to a small drop of the chemicals. They compared these observed behaviors with those they observed in mice when exposed to the same compounds. Following euthanasia, the scientists also extracted spinal cord tissue and nerve tissues for analysis.

Three of the species were immune to the acidic solution and two were immune to capsaicin, but the naked mole-rat was the only species immune to both.

They also found that the highveld mole-rate was immune to exposure to the AITC compound.

"This is an awesome finding because the highveld mole-rat is the only mammal known to be immune to 'wasabi pain,'" Park said. "It turns out that highveld mole-rats share their tunnels, their natural environment in Africa, with a stinging ant species, the natal droptail ant. The ant's sting normally activates the same pain receptors that respond to wasabi. Over time, the highveld mole-rats evolved to become unaffected by the sting."

Park and his colleagues also analyzed genetic materials from the samples they took from the mole-rats and found that the nerves of highveld mole-rats had an unusually large number of tiny structures called leak channels on their surface.

"Nature and evolution solved a pain problem for the highveld mole-rat. The leak channels make the nerves unable to convey messages about wasabi pain to the brain," Park said. "Instead of delivering the signal from the receptor to the brain, the leak channels divert the signal."

The researchers say that this finding is particularly interesting, as the evolutionary change for this species of mole-rate occurred over a short period of time -- 7 million years. The naked mole-rats also developed their immunity to the acidic solution and capsaicin quickly.

"That may seem like a long time, but in evolutionary biology, 7 million years is considered to be quite rapid," Park said.

"When we find out how to add leak channels to our own pain cells, we'll have a new way of fighting pain, without the side effect of addiction from external pain killers," he said.

CORVALLIS, Ore. - Researchers at Oregon State University have made an important advance in understanding the roles that gut bacteria play in human health.

Learning the mechanisms by which gut microbes affect the health of their hosts opens the door to the development of better, more personalized diagnostic methods and therapies.

Most studies so far have focused on how the composition of the microbiome - i.e., which organisms are present, and in what amounts - associates with health in general or various diseases.

The OSU research led by Ph.D. student Courtney Armour goes a step further by looking not just at which organisms are in the microbiome, but also what functions they might be performing. Findings were published in mSystems.

Armour, working under microbiology and statistics researcher Thomas Sharpton in OSU's College of Science, analyzed data and findings from eight different studies encompassing seven different diseases in a metagenomic meta-analysis.

Metagenomics refers to the study of genetic material recovered directly from environmental samples - in this case, human fecal samples - as opposed to from organisms cultured in a lab. A meta-analysis is a statistical technique for combining data from multiple studies.

The meta-analysis performed by Armour, Sharpton and their collaborators involved metagenomic data from nearly 2,000 stool samples collected for studies involving colorectal cancer, Crohn's disease, liver cirrhosis, obesity, rheumatoid arthritis, type 2 diabetes and ulcerative colitis.

The gut microbiota features more than 10 trillion microbial cells from about 1,000 different bacterial species. The microbial ecosystem stays in balance via cell-to-cell signaling and the release of antimicrobial peptides that keep in check certain bacterial clades.

Gut microbes interact with their human host as well, sometimes in ways that promote health, other times in ways that contribute to disease development. Dysbiosis, or imbalance, in the microbiome is commonly associated with detrimental effects to the host's health.

"In our study, we looked at how gut microbiome protein family richness, composition and dispersion relate to disease," Sharpton said.

Proteins are large, complex molecules that do most of the work in cells and are required for the structure, function and regulation of tissues and organs.

"Our analysis of protein family richness showed that patients with Crohn's disease, obesity, type 2 diabetes or ulcerative colitis feature a smaller number of protein families compared to their respective control populations," Sharpton said. "On the other hand, people with colorectal cancer had a larger number of microbiome protein families than their controls."

The researchers also looked at "beta-dispersion," which measures the compositional variation of the microbiome among a group of individuals.

"Prior work linked disease to an increase in taxonomic beta-dispersion," Sharpton said. "We looked at whether gut microbiome functional beta-dispersion is different between healthy and diseased populations and saw an increase in functional beta-dispersion in patients with colorectal cancer, Crohn's disease and liver cirrhosis. Individuals with obesity displayed reduced beta-dispersion relative to their controls."

The amount of overlap - functions associating with multiple diseases - was striking, said Armour, who added there's much more to learn.

"We really need more data," she said. "And we need more information about the subjects in the studies, about other things that may be affecting the microbiome, things like diet and geography. We need more data from diverse locations and populations to account for sources of variations."

The long-term goal, Sharpton said, is for doctors to be able to use information derived from metagenomics to diagnose diseases "more specifically, more quickly and less invasively."

"Our work points to information coded in the metagenome that could be used for that, but that requires more data to make those diagnoses more robust," he said. "We're trying to disentangle cause and effect, to resolve these needles in haystacks and find the links between the microbiome and health. Future research can leverage this new knowledge to test microbiome functions against the presence and severity of various diseases."

Have you ever spent half an hour trying to take the best photo of your pets but they won't stay still in the perfect angle? This is also true for small animal imaging research using positron emission tomography (PET). Because of this, the use of anesthesia is a widespread practice in animal imaging. It's one of the biggest limitations to imaging studies because anesthesia alters the animal's normal physiological state, blurring the answers to the questions that many researchers have been asking.

Thanks to a collaborative effort between McGill University, Montreal Canada and the University of Antwerp, Belgium this no longer needs to be the case. A new study, published in NeuroImage by researchers from the Molecular Imaging Center Antwerp (MICA) and the Douglas Mental Health University Institute of McGill University, describes a new PET imaging platform capable of simultaneously scanning multiple animals while they are awake.

The platform uses an insert developed by Min Su (Peter) Kang and Reda Bouhachi (Pedro Rosa-Neto's Team, McGill University) and an algorithm developed by MICA researchers Alan Miranda and Professor Jeroen Verhaeghe, that tracks a single animal's head movements. This collaborative effort enabled the Douglas researchers adapted the algorithm to track two animals' movements simultaneously in a PET scanner, with the help of imaging experts from The Neuro (Montreal Neurological Institute and Hospital).

"We think our breakthrough will open a new era of small animal PET imaging research and unprecedented experimental designs that many researchers have been anxious to test for a long time," says Pedro Rosa-Neto, Associate Professor in McGill's departments of Neurology & Neurosurgery and Psychiatry and a researcher at McGill's Translational Neuroimaging Laboratory.

Previous methods developed to avoid using anesthesia required external tracking or surgical implantation of devices to scan the brain of moving animals. The new method developed through this collaboration thus offers a less invasive means of conducting imaging studies and allow animals to interact in a "natural" manner during scans.

"From the start of this project our goal was to develop a practical approach to imaging awake animals. After more than 3 years of development, we delivered an approach that can be easily implemented so scientists can focus on new exciting biology questions that can be answered rather than on technical issues," says Jeroen Verhaeghe, Professor at the Molecular Imaging Center Antwerp (MICA), part of the University of Antwerp and the University Hospital Antwerp.

Thanks to this innovative platform, TNL and MICA will continue their collaboration in the hopes to answer questions that have long eluded scientists, for example, the extent to which brain cells use glucose as the main energy source. The new scanning method could also help understand the neurochemical basis of sympathy, fear, learning and memory in real time in awake animals, questions that could not previously be answered because of the use of anesthesia.

AURORA, Colo. (May 30, 2019) - Cannabis use among older adults is growing faster than any other age group but many report barriers to getting medical marijuana, a lack of communication with their doctors and a lingering stigma attached to the drug, according to researchers.

The study, the first to look at how older Americans use cannabis and the outcomes they experience, was published this month in the journal Drugs & Aging.

"Older Americans are using cannabis for a lot of different reasons," said study co-author Hillary Lum, MD, PhD, assistant professor of medicine at the University of Colorado School of Medicine. "Some use it to manage pain while others use it for depression or anxiety."

The 2016 National Survey of Drug Use and Health showed a ten-fold increase in cannabis use among adults over age 65.

The researchers set out to understand how older people perceived cannabis, how they used it and the positive and negative outcomes associated with it.

They conducted 17 focus groups in in senior centers, health clinics and cannabis dispensaries in 13 Colorado counties that included more than 136 people over the age of 60. Some were cannabis users, others were not.

"We identified five major themes," Lum said.

These included: A lack of research and education about cannabis; A lack of provider communication about cannabis; A lack of access to medical cannabis; A lack of outcome information about cannabis use; A reluctance to discuss cannabis use.

Researchers found a general reluctance among some to ask their doctors for a red card to obtain medical marijuana. Instead, they chose to pay more for recreational cannabis.

Lum said this could be driven by feeling self-conscious about asking a doctor for cannabis. That, she said, points to a failure of communication between health care providers and their patients.

"I think [doctors can] be a lot more open to learning about it and discussing it with their patients," said one focus group respondent. "Because at this point I have told my primary care I was using it on my shoulder. And that was the end of the conversation. He didn't want to know why, he didn't want to know about effects, didn't want to know about side effects, didn't want to know anything."

Some said their doctors were unable or unwilling to provide a certificate, the document needed to obtain medical marijuana. They also said physicians need to educate themselves on the latest cannabis research.

Some older users reported positive outcomes when using cannabis for pain as opposed to taking highly addictive prescription opioids. They often differentiated between using cannabis for medical reasons and using it recreationally.

"Although study participants discussed recreational cannabis more negatively than medical cannabis, they felt it was more comparable to drinking alcohol, often asserting a preference for recreational cannabis over the negative effects of alcohol," the study said.

The researchers also found that despite the legalization of cannabis in Colorado and other states, some older people still felt a stigma attached to it.

"Some participants, for example, referred to the movie `Reefer Madness' (1936) and other anti-marijuana propaganda adverts that negatively framed cannabis as immoral and illegal," the researchers said.

The study adds to the growing literature on the diversity of marijuana use patterns in older adults, said co-author Sara Honn Qualls, PhD, ABPP, professor of psychology and director of the Gerontology Center at the University of Colorado Colorado Springs.

"Older adults who use marijuana are ingesting it in a variety of ways for multiple purposes," she said. "This and other papers from the same project show growing acceptance of marijuana use for medical purposes by older adults, and a clear desire to have their primary health providers involved in educating them about options and risks.

Lum agreed.

She said Colorado, the first state to legalize recreational marijuana, provides a unique laboratory to gauge public attitudes toward cannabis.

"From a physician's standpoint this study shows the need to talk to patients in a non-judgmental way about cannabis," she said. "Doctors should also educate themselves about the risks and benefits of cannabis and be able to communicate that effectively to patients."

New research out of Loma Linda University Health suggests that unsupportive parenting styles may have several negative health implications for children, even into their adult years.

The study found that the telomeres -- protective caps on the ends of the strands of DNA -- of subjects who considered their mothers' parenting style as "cold" were on average 25% smaller compared to those who reported having a mother whose parenting style they considered "warm."

Research has found that early-life stress is associated with shorter telomeres, a measurable biomarker of accelerated cellular aging and increased disease risk later in life.

"Telomeres have been called a genetic clock, but we now know that as early life stress increases, telomeres shorten and the risk of a host of diseases increases, as well as premature death," said Raymond Knutsen, MD, MPH, lead author of the study and associate professor at Loma Linda University School of Public Health. "We know that each time a cell divides, the telomeres shorten, which shortens its lifespan."

Interestingly, mutations in genes maintaining telomeres cause a group of rare diseases resembling premature aging. "However, we know that some cells in the body produce an enzyme called telomerase, which can rebuild these telomeres," Knutsen said.

Released earlier this month, the study, "Cold parenting is associated with cellular aging in offspring: A retrospective study," uses data from 200 subjects who participated in two prospective cohort studies of Seventh-day Adventist men and women: the Adventist Health Study-1 (AHS-1) with 34,000 Californians in 1976 and AHS-2 with 96,000 subjects from the United States and Canada in 2002-2007.

The research takes a closer look at the impact parenting style has on telomere succession. "The way someone is raised seems to tell a story that is intertwined with their genetics," Knutsen said.

The study also examined the impact education and body mass index (BMI) may have on the association between cold parenting and telomere length.

"The association with parenting style was greatest among those with less education, and those who stayed overweight/obese or put on weight during follow-up, suggesting both higher education and normal BMI may provide some resilience against cold parenting and cellular aging," the study stated.

People with autism often suffer from gut problems, but nobody has known why. Researchers have now discovered the same gene mutations - found both in the brain and the gut - could be the cause.

The discovery confirms a gut-brain nervous system link in autism, opening a new direction in the search for potential treatments that could ease behavioural issues associated with autism by targeting the gut.

Chief Investigator Associate Professor Elisa Hill-Yardin, RMIT University, said scientists trying to understand autism have long been looking in the brain, but the links with the gut nervous system have only been recently explored.

"We know the brain and gut share many of the same neurons and now for the first time we've confirmed that they also share autism-related gene mutations," Hill-Yardin said.

"Up to 90% of people with autism suffer from gut issues, which can have a significant impact on daily life for them and their families.

"Our findings suggest these gastrointestinal problems may stem from the same mutations in genes that are responsible for brain and behavioural issues in autism.

"It's a whole new way of thinking about it - for clinicians, families and researchers - and it broadens our horizons in the search for treatments to improve the quality of life for people with autism."

The autism gene and the gut-brain link

The study reveals a gene mutation that affects neuron communication in the brain, and was the first identified as a cause of autism, also causes dysfunction in the gut.

The research brings together new results from pre-clinical animal studies with previously unpublished clinical work from a landmark 2003 study led by Swedish researchers and a French geneticist.

The study of two brothers with autism by Professor Christopher Gillberg (University of Gothenburg), Professor Maria Råstam (Lund University) and Professor Thomas Bourgeron (Pasteur Institute) was the first to identify a specific gene mutation as a cause of the neurodevelopmental disorder.

This mutation affects communication by altering the "velcro" between neurons that keeps them in close contact.

While the 2003 study was focused on identifying the genetic basis for autism, Gillberg and Råstam also took detailed clinical notes of the brothers' significant gastrointestinal problems.

Researchers in the Gut-Brain Axis team at RMIT have built on this clinical work with a series of studies on the function and structure of the gut in mice that have the same "velcro" gene mutation.

They team found this mutation affects:

gut contractions

the number of neurons in the small intestine

the speed that food moves through the small intestine

responses to a critical neurotransmitter important in autism (well known in the brain but not previously identified to play any major role in the gut)

Collaborator Associate Professor Ashley Franks (La Trobe University) also found significant differences in the gut microbes of mice with the mutation and those without it, even though both groups were kept in identical environments.

While this specific "velcro" mutation is rare, it is one of more than 150 autism-related gene mutations that alter neuronal connections, Hill-Yardin said.

"The link we've confirmed suggests a broader mechanism, indicating that the mutations that affect connections between neurons could be behind the gut problems in many patients."

New research horizons on the gut-brain axis

Hill-Yardin, an ARC Future Fellow and Vice-Chancellor's Senior Research Fellow in the School of Health and Biomedical Sciences at RMIT, said the work identifies a new a target for the development of therapies specifically designed to work on neurotransmitters in the gut.

"We've also identified that there's a need to better understand how existing autism medications that target neurotransmitters in the brain are affecting the gut," she said.

"Another promising path for future research is investigating how gene mutations in the nervous system relate with microbes in the gut.

"We know these microbes interact with the brain via the gut-brain axis, so could tweaking them improve mood and behaviour?

"While this wouldn't reverse the gene mutation, we might be able to tone down its effects, and make a real difference in the quality of life for people with autism and their families."

Successful new field tests of a continuous-variable quantum key distribution (CV-QKD) system over commercial fiber networks could pave the way to its use in metropolitan areas.

That is the key achievement from a joint team of Chinese scientists, published today in Quantum Science and Technology, which demonstrates CV-QKD transmission over commercial deployed fiber link with a distance of 50 kilometres.

Team leader and lead author, Prof. Hong Guo, from a joint team of Peking University and Beijing University of Posts and Telecommunications (PKU-BUPT joint team), Beijing, said: "CV-QKD provides, in principle, unconditional secret keys to protect people's data - such as banking information, emails and passwords.

"It has attracted much attention in the past few years, because it uses standard telecom components that operate at room temperature, instead of specific quantum devices such as single photon detectors etc, and it has potentially much higher secret key rates. However, most previous long-distance CV-QKD demonstrations were only done in laboratory fiber, without the disturbances caused by the field environment."

Lead authors Dr. Yichen Zhang and Prof. Song Yu, from the PKU-BUPT joint team, Beijing, said: "There are several challenges to bringing a practical CV-QKD system from a laboratory setup to the real world. Deployed commercial dark fibers are inevitably subject to much stronger perturbations from changing environmental conditions and physical stress. This in turn causes severe disturbances of the transmitted quantum states.

"They also suffer from higher losses due to splices, sharp bends and inter-fiber couplings. The software and hardware of CV-QKD modules must not only be designed to cope with all the conditions affecting the transmission fiber, but must also be robustly engineered to operate in premises designed for standard telecom equipment. Furthermore, as the systems need to run continuously and without frequent attention, they need to be designed to automatically recover from any errors and shield end users from service interruptions."

The PKU-BUPT joint research team carried out two field tests of CV-QKD over commercial fiber networks in two cities of China - Xi'an and Guangzhou - achieving transmission distances of 30.02 km (12.48 dB loss) and 49.85 km (11.62 dB loss), respectively.

Prof. Hong Guo said: "The longest previous field tests of a CV-QKD system were over a 17.52 km deployed fiber (10.25 dB loss) and a 17.7 km deployed fiber (5.6 dB loss), where the secret key rates were 0.2 kbps and 0.3 kbps, respectively.

"Comparing with these results, our results show a more than twice transmission distance, and a two orders-of-magnitude higher secret key rates, though in more lossy commercial fiber links.

"This is a significant step in bringing CV-QKD closer to everyday use. It has pushed CV-QKD towards a more practical setting, and, naturally, one may expect that a quantum-guaranteed secure metropolitan network could be built within reach of current technologies."

A study conducted by scientists from Brazil, the United States and Portugal investigated the accuracy and consistency of different satellite data collections with regard to the location and size of burned areas in the Cerrado biome, the Brazilian savanna.

The results, published in the International Journal of Applied Earth Observation and Geoinformation will help improve the output produced by Programa Queimadas, a program run by Brazil's National Space Research Institute (INPE) to monitor wildfires and burns by satellite and to calculate and forecast forest fire risk.

The study was linked to the Brazilian Fire-Land-Atmosphere System (BrFLAS), a project supported by São Paulo Research Foundation - FAPESP. Its principal investigator was Renata Libonati, a professor at the Federal University of Rio de Janeiro (UFRJ) in Brazil, in collaboration with researchers at the University of Maryland (USA) and the University of Lisbon (Portugal). The study was also one of several projects conducted as follow ups to the master's research of the first author Júlia Abrantes Rodrigues.

Several previous studies showed that fire - which can be used intelligently as part of a properly considered strategy with total area zoning and a rotating fire schedule - is indispensable to renewal the Cerrado (read more at agencia.fapesp.br/26064).

The indiscriminate, often criminal, use of fire to eliminate native plants and prepare land for crops and extensive cattle raising is a different story. "In this case, areas are burned repeatedly at very short intervals, almost always in the dry season, and no vegetation can survive. Natural adaptation is impossible," environmental engineer Alberto Setzer). Setzer is a researcher at INPE and a coauthor of the article.

"A most important aspect to consider is the atmospheric emissions from burning. Depending on the year, they can account for between 28% and 75% of Brazil's total carbon emissions, contributing substantially to global estimates, as Brazil ranks seventh among the world's countries that are the largest sources of carbon emissions. Even 28% is very significant, while 75% is extremely serious," Setzer said.

"The Amazon was the main concern in the past as far as fire was concerned, but the burning in the Cerrado has become very alarming. This biome, particularly the part known as MaToPiBa [an acronym that designates the area at the intersection between the states of Maranhão, Tocantins, Piauí and Bahia], has become a magnet for large-scale agricultural projects. For example, western Bahia has undergone brutal devastation, and almost all the natural vegetation has been removed."

Setzer noted that this change has been very drastic and swift and that the scientific community is practically unaware of it. Hence, the timeliness of this new study, which set out to answer the following question: "How much of the Cerrado is being burned?"

Data from satellites operated by reliable organizations such as NASA and the European Space Agency (ESA) are global in scale and relatively imprecise for the study of regional phenomena, according to Setzer.

"It was in this specific respect that we set out to enhance the quality of INPE's output for use in measuring burned areas," Setzer said. "The study shows the limitations and errors of both global-scale estimates and those produced by INPE. The aim was to refine our data to arrive at more precise information on burned areas, including what, when and where data, as well as the resulting emissions."

The Programa Queimadas portal offers current data on the subject. At a resolution of 1 km, it is possible to obtain data on the total burned area and burned areas by biome, year by year and month by month, as well as each biome's percentage of total burned area. The maps also show each biome's fire scars. The portal offers LANDSAT quadrant images, maps, and other detailed information for the Cerrado at a resolution of 30 m.

"In our study, we calculated the errors and uncertainties of the data provided by the satellite images. It's the first study of the kind for the Cerrado. We also found that the data are more reliable for the northern than for the southern Cerrado. This is because properties in the southern part of the biome are far smaller, so the use of fire occurs in relatively small areas rather than over very large swathes of land. In the northern portion, in areas such as Bananal Island, we measured almost continuous fires in areas as large as 10,000 km2 in some years. That never happens in parts of northern São Paulo or southern Minas Gerais [Southeast Brazil], where the land-use pattern is quite different. It's an important finding because it shows you can't have a single algorithm for the entire biome," Setzer explained.

At present, the impact on the Cerrado is greatest in areas of arable land. "The Cerrado is being practically destroyed, and the land is being converted to crops or pasture. In most cases, this is being done in breach of the environmental legislation. In the Amazon, the law requires that 80% of any property must be left untouched. In the Cerrado, this requirement applies to only 30%, but even that small proportion isn't enforced," he said.

Scientists at Texas A&M University are harnessing the combined power of organic nanomaterials-based chemistry and a natural product found in crustacean exoskeletons to help bring emergency medicine one step closer to a viable solution for mitigating blood loss, from the hospital to the battlefield.

Hemorrhage is a leading cause of death in traumatic injuries, ranking fourth in the United States at a total cost of $671 billion in 2013. Working with an interdisciplinary team involving collaborators from Assiut University in Egypt, Texas A&M chemist Karen Wooley's research group has developed a bioabsorbable wound dressing that builds on the already proven blood-flow-staunching properties of chitosan - a natural material widely used in commercial wound dressings - by taking them nanoscale to boost their effectiveness and impact.

Wooley's team, led by Texas A&M chemistry Ph.D. student and NASA Space Technology Research Fellow Eric Leonhardt, successfully encapsulated highly entangled nanofibers of chitosan within a sugar-based hydrogel that dissolves in as little as seven days, leaving behind a significantly larger available wound-healing surface while eliminating the need for subsequent physical removal. Their results are published in Nature Communications.

"Bioabsorbable wound dressings that can be applied and left in the injury site are desirable for a variety of blood loss scenarios -- for example, to control bleeding in traumatic injuries and to save lives on both civilian and military fronts," said Leonhardt, who served as first author on the team's paper. "The composite materials we've developed are malleable and could be easily administered to wound sites. They have also performed significantly better in terms of reducing the amount of blood loss and the time required to achieve hemostasis against commercially available bioabsorbable wound dressing in several animal models."

Team members in addition to Leonhardt include Texas A&M materials science and engineering Ph.D. student Nari Kang; Dr. Mahmoud Elsabahy, assistant director of the Texas A&M Laboratory for Synthetic-Biologic Interactions and director of the Assiut Clinical Center of Nanomedicine at Al-Rajhy Liver Hospital; and Dr. Mostafa A. Hamad, a professor in the Department of Surgery within the Assuit Faculty of Medicine.

Elsabahy recognized that, while chitosan is a desirable option in such dressings due to its proven efficacy in slowing blood flow and because it offers bonus antimicrobial properties, it also has a tendency to clump, rendering it difficult to incorporate into a bioabsorbable material. The team overcame that obstacle by loading chitosan into a nanostructured template scaffold to better disperse it and increase its interaction with blood components, thereby speeding up both absorption and healing.

As a first step in their breakthrough discovery process, the researchers developed hydrogels from cyclodextrins - a type of saccharide with hydrolytically degradable linkages - designed with sites that were capable of ionically interacting with and binding to chitosan molecules. After freeze-drying the resulting composite material, they exposed it to a solution that removed the template scaffold. They then used scanning electron microscopy to further analyze the chitosan, which they determined had assembled into mats of highly entangled nanofibers measuring about 10-to-20 nanometers in diameter.

"Not only are these fibers considerably smaller than what has been previously reported for chitosan, they also are highly desirable, given that the corresponding increase in surface area is expected to greatly enhance hemostatic effect," said Elsabahy, who conceived the project. "We believe this work will enhance the scope of chitosan as a hemostatic technology through the demonstration of its fabrication and use as a bioabsorbable wound dressing."

To date, the team has applied their composite wound dressings to liver injuries in rats, rabbits and pigs, measuring the amount of blood loss, time to hemostasis and mean arterial pressure in each case to gauge effectiveness. The dressings also were implanted in the liver and imaged after seven days to evaluate the biodegradation of the composite materials. No residues could be observed in any of the settings.

"Hemorrhage is responsible for more than 35 percent of pre-hospital deaths and more than 40 percent of deaths within the first 24 hours of injury," Leonhardt said. "Hemostatic dressings have the potential to reduce morbidity and mortality through the early control of hemorrhage. These dressings can be included in first aid kits and carried by soldiers to save lives in the battlefield, and they can be also utilized to control bleeding in various injury scenarios and surgical procedures in hospitals. Absorbable hemostatic dressing can be left in the injury site and eliminate the necessity for carrier removal, which reduces the risk of re-bleeding -- in case of carrier removal of non-absorbable dressings -- and decreases the duration required for the surgical interventions."

Wooley intends to extend this initial work to the evaluation of the materials in studies that simulate lethal hemorrhage scenarios, followed by clinical trials. In addition, she would like to conduct future fundamental studies to further explore the mechanism of chitosan nanofiber formation within the template scaffolds, with the aim of ultimately achieving control over the assembly to enable tuning and optimization of the resulting morphology of the wound dressings.

BUFFALO, N.Y. -- A new University at Buffalo study based on levels before, during and after the Beijing Olympics reveals how air pollution affects the human body at the level of metabolites.

Researchers found that 69 metabolites changed significantly when air pollution changed. Their results were published today (May 29) in the journal Environmental Health Perspectives.

The study identified two major metabolic signatures, one consisting of lipids and a second that included dipeptides, polyunsaturated fatty acids, taurine, and xanthine. Many of those metabolites are involved in oxidative stress, inflammation, cardiovascular and nervous systems, researchers note.

The findings are based on the Beijing Olympics Air Pollution study, conducted during the 2008 Olympic Games in China, when temporary air pollution controls were implemented. The study was led by UB epidemiologist Lina Mu.

The study enrolled 201 adults prior to Beijing's air quality improvement initiative, when air pollution was high. Researchers followed them during the Games, when air pollution was low, and afterward, when levels returned to their usual high in the city of 21 million people. A subset of 26 non-smokers aged 30 to 65 was selected for the metabolomics analysis.

Metabolites are small molecules that are the end products of environmental exposures, such as air pollution, and body metabolism. "Think of our body as a society. These metabolites fulfill different positions, such as teacher, farmer, worker, soldier. We need each one functioning properly in order to maintain a healthy system," said Mu, PhD, associate professor of epidemiology and environmental health in UB's School of Public Health and Health Professions.

"Our study found that the human body had systemic changes at the metabolite level before, during and after the 2008 Beijing Olympics, when ambient air pollution changed drastically," said Zhongzheng Niu, a PhD candidate and a paper co-author.

The molecules mostly belonged to the lipid and dipeptide families.

The study provides researchers with a broader view of the molecular mechanism underlying the impact of air pollution on the human body. Most previous studies only looked at a small number of molecules. However, the human body is complex and molecules affect one another.

Mu and her colleagues used the "omics" method, a new platform that can measure a whole collection of all detectable metabolites -- 886 in their study -- simultaneously. Instead of examining these molecules one by one, Mu and her team used network analysis to analyze them all together.

"We found that these metabolites together depicted a relatively comprehensive picture of human body responses to air pollution," said paper co-author Rachael Hageman Blair, associate professor of biostatistics at UB. She and her team developed the novel analysis method used in the study

The responses include cellular stability, oxidative stress, anti-oxidation and inflammation.

Researchers measured metabolomics repeatedly when air pollution was high, low and high. Such a design mimicked a "natural experiment" while controlling for variations unrelated to air pollution changes. This provided stronger evidence than previous studies.

Air pollution is an environmental exposure that can't be avoided by people who live in places like Beijing. The World Health Organization reports that 91 percent of the world's population lives in places where air quality exceeds WHO guidelines.

Once inhaled, air pollutants stimulate the body's respiratory system, including the nose and lungs. Some cells in the body may be directly insulted by these air pollutants, their membrane may be broken, their secretion may be disordered, and they may send out signaling molecules to other organs for subsequent responses, Mu explains. Metabolites are all these broken membranes, secreted products and signals.

"Capturing these molecules tells us what is going on when people are exposed to air pollution," Mu said.

Air pollution also induces cellular oxidative stress, which breaks cell membranes.

Researchers found that some molecules that serve as building blocks of cell membranes were elevated when air pollution levels rose. Broken cell membranes release different kinds of lipid molecules. Some of these lipid molecules, with the help of enzymes, turn to inflammatory molecules, which could be harmful to the body.

"The good thing is that we also found some protective molecules, namely antioxidants, also increased when air pollution is high, indicating our body has a defense system to reduce harm," Mu said.

Studies such as this one may help identify individuals most vulnerable to air pollution, as well as finding potential biological pathways to guide treatment that reduces harm to the body, Mu said.

EAST BOOTHBAY, Maine - New research connects recent changes in the movement of North Atlantic right whales to decreased food availability and rising temperatures in Gulf of Maine’s deep waters. Right whales have been showing up in unexpected places in recent years, putting the endangered species at increased risk. The study, which was published in Oceanography and conducted by scientists from more than 10 institutions, provides insights to this key issue complicating conservation efforts.

“The climate-driven changes rippling throughout the Gulf of Maine have serious consequences for the small number of remaining right whales,” said Nick Record, a senior research scientist at Bigelow Laboratory for Ocean Sciences and lead author on the paper. “Climate change is outdating many of our conservation and management efforts, and it’s difficult to keep up with the rapid evolution of this ecosystem.”

Climate change has shifted circulation patterns in the North Atlantic Ocean, including the currents that flow into the Gulf of Maine’s depths. This study found that some of these deep waters have warmed nearly 9 degrees Fahrenheit since 2004 – twice as much as the fastest warming waters at the surface. These changes have drastically reduced the supply of right whale's primary prey – a high-fat, rice-sized crustacean called Calanus finmarchicus.

“Ocean conditions determine where right whales go and when they go there,” said Dan Pendleton, a research scientist at the New England Aquarium and an author on the paper. “For decades, we have known where and when to find right whales. Now that paradigm is breaking down, and we’re seeing changes to behaviors that had remained consistent since before people starting observing them.”

Right whales have historically made an autumn journey to the mouth of the Bay of Fundy to feast in preparation for winter. In the absence of abundant Calanus in that region, right whales are following their food – which means foraging well outside of the areas established to protect them.

The misalignment between conservation measures and the whales’ current behavior makes them much more vulnerable to lethal encounters with ships and fishing gear. However, the researchers believe that the strong connection between water temperature, Calanus, and right whales makes it possible to predict where new right whale habitats develop, and to plan accordingly.

“Calanus is the primary reason that right whales, and many other marine animals, including herring, have thrived in the Gulf of Maine,” said Jeff Runge, a research scientist at the Gulf of Maine Research Institute and professor at the University of Maine. “But Calanus finmarchicus is a subarctic species living at the southern edge of its range here. Its presence and ability to store high energy fat is at risk by the warming of deep waters, where it spends part of its life cycle.”

As part of previous research in 2012, Record and Pendleton used data about Calanus and oceanographic conditions to develop an algorithm to identify right whale habitats. Working with collaborators, including Andrew Pershing from the Gulf of Maine Research Institute, they determined that the region south of Nantucket might be a previously unknown right whale habitat. Recent surveys have revealed the area is indeed a hotspot for the species, and the researchers now hope to develop similar tools to help people predict and prepare for future movement of right whales.

Good data are critical to accurate predictions, however, and routine measurements to monitor change in Calanus abundance in the Gulf of Maine have been drastically reduced due to a lack of funding. Runge and others in the research community are working hard to recover this capability in the region, and Record hopes that he may be able to develop models that use alternative data sources to forecast right whale locations, such as monitoring seawater for signs of whale DNA and collecting observations by citizen scientists.

“Conservation in this age of climate change requires a proactive approach,” Record said. “Developing computer models that can anticipate change is our best chance at getting the edge we need to protect right whales and other species in the rapidly changing Gulf of Maine.”

A Florida State University researcher has found gender inequality in U.S. states is bad for everybody's health.

In a new study published in the American Sociological Review, FSU Assistant Professor Patricia Homan developed a new structural sexism approach to the study of gender inequality and health. Her approach goes beyond sexist mistreatment by individuals to examine how the degree of systematic gender inequality in power and resources -- i.e. structural sexism -- in a society can impact people's health.

"Researchers have known for decades that the experience of being sexually harassed or discriminated against can have a harmful effect on a woman's health," Homan said. "But much less is known about the broader health consequences of living in a social environment where power, resources, roles and opportunities are unequally distributed along gender lines."

Structural sexism can be evident in major social institutions, such as the government and the economy, in interpersonal interactions and relationships, such as marriages and in individuals' beliefs and identities. Homan established concrete ways to measure structural sexism within U.S. states, within heterosexual marriages and at the individual level and examined its effects on men's and women's health.

To conduct her research, Homan compiled data from multiple sources including the U.S. Census and the National Longitudinal Study of Youth. Based on a sample of more than 3,300 U.S. adults, Homan found that at the state level structural sexism resulted in worse health outcomes for both men and women alike.

Those living in states with the highest levels of structural sexism, such as Utah, Wyoming, Mississippi, Louisiana and Oklahoma, reported higher levels of chronic conditions, worse self-reported health and had worse physical function at age 40 and 50.

"This means that at the macro level structural sexism is universally harmful for population health," Homan said.

To illustrate the magnitude of the health effects, Homan noted, that women exposed to high levels of structural sexism in their home state had roughly twice as many health issues as women living in states with lower levels.

Put differently, a woman living in a state with high structural sexism looked seven years older in terms of her health profile than her counterpart in a state with low levels of structural sexism. Homan found the states with the lowest structural sexism were Maryland, California, Massachusetts, Vermont and Hawaii.

Homan created several measures of state level structural sexism designed to capture the degree to which men and women are unequal in four arenas of society -- political, economic, cultural and physical/reproductive.

The measures included: the gender wage gap, gender differences in labor force participation and poverty rates, the proportion of state legislature seats occupied by men, the prevalence of religious conservatives in each state -- which is linked to traditional gender roles and the exclusion of women from leadership positions -- and the proportion of women who live in a county without an abortion provider.

"Public health scholars and international human rights organizations consider reproductive choice and access to a full range of reproductive health care services to be a fundamental human right," Homan said. "It's also considered a precondition for women's equal citizenship and participation in social, political and economic life."

Homan said there are several policy implications to consider as a result of her research.

"The first thing we need to realize is that gender inequality in the United States is not only a human rights issue, but also a public health problem," she said. "Therefore, gender equity policy is health policy."

This means that policies aiming to close the gender wage gap, increase women's political representation, protect and expand access to reproductive health services, or otherwise promote gender equity, also have the potential to improve health for all members of society.