Monkey caloric restriction study shows big benefit; contradicts earlier study

The latest results from a 25-year study of diet and aging in monkeys shows a significant reduction in mortality and in age-associated diseases among those with calorie-restricted diets. The study, begun at the University of Wisconsin-Madison in 1989, is one of two ongoing, long-term U.S. efforts to examine the effects of a reduced-calorie diet on nonhuman primates.The study of 76 rhesus monkeys, reported Monday in Nature Communications, was performed at the Wisconsin National Primate Research Center in Madison. When they were 7 to 14 years of age, the monkeys began eating a diet reduced in calories by 30 percent. The comparison monkeys, which ate as much as they wanted, had an increased risk of disease 2.9 times that of the calorie-restricted group, and a threefold increased risk of death.”We think our study is important because it means the biology we have seen in lower organisms is germane to primates,” says Richard Weindruch, a professor of medicine at the School of Medicine and Public Health, and one of the founders of the UW study. “We continue to believe that mechanisms that combat aging in caloric restriction will offer a lead into drugs or other treatments to slow the onset of disease and death.”Restricting the intake of calories while continuing to supply essential nutrients extends the lifespan of flies, yeast and rodents by as much as 40 percent. Scientists have long wanted to understand the mechanisms for caloric restriction. “We study caloric restriction because it has such a robust effect on aging and the incidence and timing of age related disease,” says corresponding author Rozalyn Anderson, an assistant professor of geriatrics. “Already, people are studying drugs that affect the mechanisms that are active in caloric restriction. There is enormous private-sector interest in some of these drugs.”Still, the effects of caloric restriction on primates have been debated. …

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New, inexpensive production materials boost promise of hydrogen fuel

Generating electricity is not the only way to turn sunlight into energy we can use on demand. The sun can also drive reactions to create chemical fuels, such as hydrogen, that can in turn power cars, trucks and trains.The trouble with solar fuel production is the cost of producing the sun-capturing semiconductors and the catalysts to generate fuel. The most efficient materials are far too expensive to produce fuel at a price that can compete with gasoline.”In order to make commercially viable devices for solar fuel production, the material and the processing costs should be reduced significantly while achieving a high solar-to-fuel conversion efficiency,” says Kyoung-Shin Choi, a chemistry professor at the University of Wisconsin-Madison.In a study published last week in the journal Science, Choi and postdoctoral researcher Tae Woo Kim combined cheap, oxide-based materials to split water into hydrogen and oxygen gases using solar energy with a solar-to-hydrogen conversion efficiency of 1.7 percent, the highest reported for any oxide-based photoelectrode system.Choi created solar cells from bismuth vanadate using electrodeposition — the same process employed to make gold-plated jewelry or surface-coat car bodies — to boost the compound’s surface area to a remarkable 32 square meters for each gram.”Without fancy equipment, high temperature or high pressure, we made a nanoporous semiconductor of very tiny particles that have a high surface area,” says Choi, whose work is supported by the National Science Foundation. “More surface area means more contact area with water, and, therefore, more efficient water splitting.”Bismuth vanadate needs a hand in speeding the reaction that produces fuel, and that’s where the paired catalysts come in.While there are many research groups working on the development of photoelectric semiconductors, and many working on the development of water-splitting catalysts, according to Choi, the semiconductor-catalyst junction gets relatively little attention.”The problem is, in the end you have to put them together,” she says. “Even if you have the best semiconductor in the world and the best catalyst in the world, their overall efficiency can be limited by the semiconductor-catalyst interface.”Choi and Kim exploited a pair of cheap and somewhat flawed catalysts — iron oxide and nickel oxide — by stacking them on the bismuth vanadate to take advantage of their relative strengths.”Since no one catalyst can make a good interface with both the semiconductor and the water that is our reactant, we choose to split that work into two parts,” Choi says. “The iron oxide makes a good junction with bismuth vanadate, and the nickel oxide makes a good catalytic interface with water. So we use them together.”The dual-layer catalyst design enabled simultaneous optimization of semiconductor-catalyst junction and catalyst-water junction.”Combining this cheap catalyst duo with our nanoporous high surface area semiconductor electrode resulted in the construction of an inexpensive all oxide-based photoelectrode system with a record high efficiency,” Choi says.She expects the basic work done to prove the efficiency enhancement by nanoporous bismuth vanadate electrode and dual catalyst layers will provide labs around the world with fodder for leaps forward.”Other researchers studying different types of semiconductors or different types of catalysts can start to use this approach to identify which combinations of materials can be even more efficient,” says Choi, whose lab is already tweaking their design. “Which some engineering, the efficiency we achieved could be further improved very fast.”Story Source:The above story is based on materials provided by University of Wisconsin-Madison. The original article was written by Chris Barncard. Note: Materials may be edited for content and length.

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Evidence mixed on the usefulness of echinacea for colds

For people seeking a natural treatment for the common cold, some preparations containing the plant Echinacea work better than nothing, yet “evidence is weak,” finds a new report from The Cochrane Library. The evidence review revealed no significant reductions in preventing illness, but didn’t rule out “small preventive effects.”The six authors conducted reviews on this subject in 1998, 2006 and 2008 and wanted to do an update to include several new trials conducted since then. “We’ve been doing this for so long and are very familiar with past research — which has been mixed from the very beginning,” said author Bruce Barrett, M.D., Ph.D. in the department of family medicine at the University of Wisconsin in Madison.The research team reviewed 24 randomized controlled trials to determine whether Echinacea was a safe and effective cold prevention and treatment. Trials included 4631 participants and 33 preparations, along with placebo. Echinacea products studied in these trials varied widely according to characteristics of three different plant species, the part of the plant used and method of manufacturing.People who get colds spend $8 billion annually on pharmaceutical products, including supplements such as Echinacea, Barrett noted. The authors’ meta-analyses suggest that at least some Echinacea preparations may reduce the relative risk of catching a cold by 10 to 20 percent, a small effect of unclear clinical significance. The most important recommendation from the review for consumers and clinicians is a caution that Echinacea products differ greatly and that the overwhelming majority of these products have not been tested in clinical trials.Barrett added that “it looks like taking Echinacea may reduce the incidence of colds. For those who take it as a treatment, some of the trials report real effects — but many do not. Bottom line: Echinacea may have small preventive or treatment effects, but the evidence is mixed.””The paper does support the safety and efficacy of Echinacea in treating colds and highlights the main issue of standardizing herbal medicines,” commented Ron Eccles, Ph.D., director of the Common Cold Centre & Healthcare Clinical Trials at Cardiff University’s School of Biosciences in Wales.Story Source:The above story is based on materials provided by Health Behavior News Service, part of the Center for Advancing Health. …

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Freshwater biodiversity put on the map for planners and policymakers

Oct. 16, 2013 — When it comes to economic growth and environmental impacts, it can seem like Newton’s third law of motion is the rule — for every action, there is an equal and opposite reaction — and that in most cases, the economy prospers and the environment suffers.A team of UW-Madison researchers is hoping to help change that narrative and add a little ecology to economic decision making by forecasting how future policies regarding urban development and agricultural cultivation may impact aquatic ecosystems, which harbor astounding amounts of biodiversity and provide humans with vital goods and services.”The idea is to see what future land use changes may look like under different policies, and think about where potential threats to freshwater would be most severe,” says Sebastián Martinuzzi, a post-doctoral researcher at the University of Wisconsin-Madison. “We are not trying to predict the ‘true’ future, but rather to visualize potential economic trends and their environmental consequences.”Martinuzzi, who works in Professor Volker Radeloff’s lab in the Department of Forest and Wildlife Ecology, is lead author of a report entitled “Land Use Change and Freshwater Conservation,” published Oct. 15 in the journal Global Change Biology. In the study, a team of UW ecologists and collaborating economists mapped out various economic development scenarios and connected them to impacts on freshwater species diversity across the United States.Every acre of crops put into production and each paved cul-de-sac in a new subdivision can change how water moves across the land, its temperature, and the levels of sediment and pollutants flowing into downstream freshwater ecosystems.Using computer modeling and GIS mapping, Martinuzzi and the team developed four different scenarios to help illustrate future human endeavors. In their models, the researchers found that the news isn’t all bad. Crop cover is actually projected to go down under certain policy scenarios in the Midwest, which could signal an opportunity to purchase fallow fields for conservation purposes. However, in places like California and the southeastern U.S., urbanization is likely going to be a big stressor that could portend a tough future for fishes and amphibians.The study was also able to put a number on the give-and-take of economic and ecological considerations. For example, under a “business as usual” scenario where policies remain as they are today, 34 percent of watersheds are expected to be impacted by urban development while, in an “urban containment” scenario, only 13 percent of watersheds would be affected as the spread of urban areas is minimized.”At a minimum, we hope this can help policy makers or planners think about ways we could minimize the impact from future land development,” says Stephanie Januchowski-Hartley, from UW-Madison’s Center for Limnology and a contributing author of the paper. “If a certain amount [of urban development or crop cover] is going to push 10 or 20 percent of freshwater ecosystems beyond a healthy threshold, then we, as a society, have to start asking ourselves if that is something that we’re all willing to live with.”

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Panda poop microbes could make biofuels of the future

Sep. 10, 2013 — Unlikely as it may sound, giant pandas Ya Ya and Le Le in the Memphis Zoo are making contributions toward shifting production of biofuels away from corn and other food crops and toward corn cobs, stalks and other non-food plant material.Scientists presented an update today on efforts to mine Ya Ya and Le Le’s assets for substances that could do so during the 246th National Meeting & Exposition of the American Chemical Society (ACS). And if things work out, giant pandas Er Shun and Da Mao in the Toronto Zoo will be joining the quest by making their own contributions.”The giant pandas are contributing their feces,” explained Ashli Brown, Ph.D., who heads the research. “We have discovered microbes in panda feces might actually be a solution to the search for sustainable new sources of energy. It’s amazing that here we have an endangered species that’s almost gone from the planet, yet there’s still so much we have yet to learn from it. That underscores the importance of saving endangered and threatened animals.”Brown and her students, based at Mississippi State University, now have identified more than 40 microbes living in the guts of giant pandas at the Memphis Zoo that could make biofuel production from plant waste easier and cheaper. That research, Brown added, also may provide important new information for keeping giant pandas healthy.Ethanol made from corn is the most common alternative fuel in the U.S. However, it has fostered concerns that wide use of corn, soybeans and other food crops for fuel production may raise food prices or lead to shortages of food.Brown pointed out that corn stalks, corn cobs and other plant material not used for food production would be better sources of ethanol. However, that currently requires special processing to break down the tough lignocellulose material in plant waste and other crops, such as switchgrass, grown specifically for ethanol production. Breaking down this material is costly and requires a pretreatment step using heat and high pressure or acids. …

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Massive storm pulls water and ammonia ices from Saturn’s depths

Sep. 3, 2013 — Once every 30 years or so, or roughly one Saturnian year, a monster storm rips across the northern hemisphere of the ringed planet.In 2010, the most recent and only the sixth giant storm on Saturn observed by humans began stirring. It quickly grew to superstorm proportions, reaching 15,000 kilometers (more than 9,300 miles) in width and visible to amateur astronomers on Earth as a great white spot dancing across the surface of the planet.Now, thanks to near-infrared spectral measurements taken by NASA’s Cassini orbiter and analysis of near-infrared color signatures by researchers at the University of Wisconsin-Madison, Saturn’s superstorm is helping scientists flesh out a picture of the composition of the planet’s atmosphere at depths typically obscured by a thick high-altitude haze.The key finding: cloud particles at the top of the great storm are composed of a mix of three substances: water ice, ammonia ice, and an uncertain third constituent that is possibly ammonium hydrosulfide. According to the Wisconsin researchers, the observations are consistent with clouds of different chemical compositions existing side-by-side, although a more likely scenario is that the individual cloud particles are composed of two or all three of the materials.Writing in the current edition (Sept. 9, 2013) of the journal Icarus, a team led by UW-Madison Space Science and Engineering Center planetary scientists Lawrence Sromovsky, and including Kevin Baines and Patrick Fry, reports the discovery of the icy forms of water and ammonia. Water in the form of ice has never before been observed on Saturn.”We think this huge thunderstorm is driving these cloud particles upward, sort of like a volcano bringing up material from the depths and making it visible from outside the atmosphere,” explains Sromovsky, a senior scientist at UW-Madison and an expert on planetary atmospheres. “The upper haze is so optically pretty thick that it is only in the stormy regions where the haze is penetrated by powerful updrafts that you can see evidence for the ammonia ice and the water ice. Those storm particles have an infrared color signature that is very different from the haze particles in the surrounding atmosphere.”Scientists believe Saturn’s atmosphere is a layered sandwich of sorts, with a deck of water clouds at the bottom, ammonia hydrosulfide clouds in the middle, and ammonia clouds near the top, just below an upper tropospheric haze of unknown composition that obscures almost everything.The latest great storm on Saturn and the presence of the Cassini probe now orbiting the planet gave scientists a chance to peek beneath the haze and learn more about the dynamics and chemical composition of the planet’s deep atmosphere.First noticed by amateur astronomers, the massive storm works like the much smaller convective events on Earth, where air and water vapor are pushed high into the atmosphere, resulting in the towering, billowing clouds of a thunderstorm. On Saturn, not only are the storms much bigger, they are far more violent, with models predicting vertical winds of more than 300 miles per hour for these rare giant storms.The effect, Sromovsky says, is to loft the aerosols found deep in the atmosphere to the visible cloud tops, providing a rare glimpse of normally hidden materials. “It starts at the water cloud level and develops a huge convective tower. …

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Researchers develop software tool for cancer genomics

Aug. 26, 2013 — Researchers at the Medical College of Wisconsin (MCW) have developed a new bioinformatics software tool designed to more easily identify genetic mutations responsible for cancers. The tool, called DrGaP, is the subject of a new paper published in the American Journal of Human Genetics.Xing Hua, Ph.D., postdoctoral fellow in biostatistics at the National Cancer Institute, and a former visiting scholar at MCW, is the first author of the paper. Yan Lu, Ph.D., assistant professor of physiology, is corresponding author; and Pengyuan Liu, Ph.D., associate professor of physiology at MCW, is the co-corresponding author.Cancers are caused by the accumulation of genomic alterations, or mutations. Genomic sequencing identifies two specific types of mutations: driver mutations, which are responsible for cancer, and passenger mutations, which are irrelevant to tumor development. A major challenge in cancer genome sequencing is discriminating between the two types of mutations.The authors incorporated statistical methods and bioinformatics tools into the computational tool DrGaP, which stands for “Driver Genes and Pathways.””DrGaP is immediately applicable to cancer genome sequencing studies and will lead a more complete identification of altered driver genes and driver signaling pathways in cancer,” said Dr. Liu. “Biological knowledge of the mutation process is fully integrated into the models, and provides several significant improvements and increased power over current methods.”The researchers note that DrGaP not only recaptured a large majority of driver genes previously reported in other studies, but also identified much longer list of additional candidate genes whose mutations may be linked to cancer. This data demonstrates the extreme complexity of tumor cells and has important implications in targeted cancer therapy.

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The concussed brain at work: fMRI study documents brain activation during concussion recovery

Aug. 19, 2013 — For the first time, researchers have documented irregular brain activity within the first 24 hours of a concussive injury, as well as an increased level of brain activity weeks later — suggesting that the brain may compensate for the injury during the recovery time.The findings are published in the September issue of the Journal of the International Neuropsychological Society.Thomas Hammeke, PhD, professor of psychiatry and behavioral medicine at the Medical College of Wisconsin, is the lead author. Collaborators at the Cleveland Clinic; St. Mary’s Hospital in Enid, Okl.; the University of North Carolina; Franklin College in Franklin, Ind., and the Marshfield Clinic in Marshfield, Wis., co-authored the paper.To study the natural recovery from sports concussion, 12 concussed high school football athletes and 12 uninjured teammates were evaluated at 13 hours and again at seven weeks following concussive injury.The concussed athletes showed the expected postconcussive symptoms, including decreased reaction time and lowered cognitive abilities. Imaging via fMRI (functional magnetic resonance imaging) showed decreased activity in select regions of the right hemisphere of the brain, which suggests the poor cognitive performance of concussion patients is related to that underactivation of attentional brain circuits.Seven weeks post-injury, the concussed athletes showed improvement of cognitive abilities and normal reaction time. However, imaging at that time showed the post-concussed athletes had more activation in the brain’s attentional circuits than did the control athletes.”This hyperactivation may represent a compensatory brain response that mediates recovery,” said Dr. Hammeke. “This is the first study to demonstrate that reversal in activation patterns, and that reversal matches the progression of symptoms from the time of the injury through clinical recovery.””Deciding when a concussed player should return to the playing field is currently an inexact science,” said Dr. Stephen Rao, director of the Schey Center for Cognitive Neuroimaging at the Cleveland Clinic and a senior author. “Measuring changes in brain activity during the acute recovery period can provide a scientific basis for making this critical decision.”Each year, an estimated 3.8 million people sustain a traumatic brain injury (TBI). …

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Psychiatric patients given smoking-cessation treatment less likely to be rehospitalized

Aug. 15, 2013 — Patients who participated in a smoking-cessation program during hospitalization for mental illness were able to quit smoking and were less likely to be hospitalized again for their psychiatric conditions, according to a new study led by a Stanford University School of Medicine scientist.The findings counter a longstanding assumption, held by many mental-health experts, that smoking serves as a useful tool in treating some psychiatric patients.Smoking among such patients has been embedded in the culture for decades, with cigarettes used as part of a reward system. Indeed, clinicians sometimes smoke alongside patients as a way of creating a rapport with them, said Judith Prochaska, PhD, MPH, associate professor of medicine at the Stanford Prevention Research Center and lead author of the study.The result is that psychiatric patients are among the country’s most prolific smokers and among those most likely to die of smoking-related ailments, Prochaska said. Nearly half of the cigarettes sold in the United States are to people with psychiatric or addictive disorders, according to data from the U.S. Centers for Disease Control and Prevention. The average life expectancy for people with severe mental illness is 25 years less than that of the general population, and their leading cause of death is chronic illness, mostly tobacco-related.Prochaska said it has long been thought that if these patients quit smoking, it would be detrimental to their recovery — that they would lose a critical crutch for coping with stress. However, she pointed out that the daily cycle of nicotine withdrawal a smoker experiences creates a great deal of stress, and that mental-health providers are well-equipped to assist patients with developing healthier forms of coping.The new study showed that a simple intervention that included periodic contact with a counselor, written and computerized materials, and the use of nicotine patches could support, rather than harm, the patients’ mental health, she said.”This is a very low-cost, brief intervention that helped patients quit smoking and offers evidence that it may have helped their mental health recovery,” said Prochaska, who focuses on developing interventions to treat tobacco dependence in people with mental illness or addictive disorders.She said the study, done in collaboration with researchers at UC-San Francisco, is the first to examine the impact of a stop-smoking intervention in adult psychiatric patients. It will be published online Aug. 15 in the American Journal of Public Health.Michael Fiore, MD, MPH, director of the University of Wisconsin Center for Tobacco Research and Intervention and a leader in national policy for tobacco treatment who was not involved in the study, said the paper “provides powerful evidence that evidence-based tobacco dependence treatments can substantially increase quit rates among psychiatric inpatients. We know that psychiatric patients smoke at very high rates and are at tremendous risk from their smoking. …

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Newly identifed molecules necessary for memory formation

Aug. 14, 2013 — Memory decline is a part of aging for most people, but very few treatments are available to reverse this loss because the deeper cellular mechanisms underlying memory formation are not fully known.A new paper from researchers at the University of Wisconsin-Milwaukee (UWM), led by Professor of Psychology Karyn Frick, identifies a new cellular mechanism necessary for memory.Frick and her team investigated a cell-signaling pathway in the hippocampus — an area of the brain critical to learning and memory — and found that it must be activated for learning and memory to take place. Findings were recently published in the Journal of Neuroscience.The Wnt signaling pathway has been associated with learning and shown to play a role in neuron development, but not specifically in memory formation.Using female mice, the team found that learning about objects not only activated the canonical Wnt pathway in the hippocampus, but also that Wnt signaling was necessary for the mice to form a memory of the objects. These data suggest a vital new role for this molecular pathway in hippocampal memory formation.Because Wnt signaling is impaired in aging and Alzheimer’s disease, these findings point to Wnt signaling as a new target for drug discovery.”This information is essential for understanding what happens in the brain when memory formation doesn’t happen properly, like during aging and in Alzheimer’s disease,” says Frick. “The goal of my lab’s research is to identify the specific molecules in the brain that are necessary for memory formation, which could lead to the development of new drugs for age-related memory loss that target these specific molecules.”Now Frick’s team plans to determine whether treatments that activate canonical Wnt signaling can reverse memory deficits in aged female mice.Other authors of the paper included Ashley Fortress, Sarah Schram and Jennifer Tuscher in Frick’s lab. This study was funded by UWM and by an Ellison Medical Foundation/American Federation for Aging Research Postdoctoral Fellowship in Aging.

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Children exposed to lead three times more likely to be suspended from school

Aug. 14, 2013 — Children who are exposed to lead are nearly three times more likely to be suspended from school by the 4th grade than children who are not exposed, according to a new University of Wisconsin-Madison study funded jointly by the Robert Wood Johnson Foundation and the Wisconsin Partnership Program Education and Research Committee.”Students who are suspended from school are at greater risk of dropping out, twice as likely to use tobacco, and more likely to engage in violent behavior later in life,” says first author Michael Amato, a doctoral candidate in psychology and the Nelson Institute for Environmental Studies at UW-Madison. “Our study found that children exposed to lead were more than twice as likely to be suspended in the 4th grade, which means that lead may be more responsible for school discipline problems than many people realize.”Nationally, African-American students are three times more likely to be suspended than white students. The same discipline gap was found in the Wisconsin study, but 23 percent of the disparity was explained by differences in rates of lead exposure. Many previous studies have documented disparities in school discipline, but few have specified the underlying factors.”We knew that lead exposure decreases children’s abilities to control their attention and behavior, but we were still surprised that exposed children were so much more likely to be suspended,” said Sheryl Magzamen, a public health researcher who also worked on the UW-Madison study. Magzamen is now an assistant professor at the University of Oklahoma.Researchers cross-referenced medical data of nearly 4,000 children exposed to lead with 4th grade disciplinary records in the Milwaukee school district. They found that children who had been exposed to lead were nearly three times more likely to be suspended in the fourth grade than children who had not been exposed, even after controlling for income, race/ethnicity, and gender.Experiments on non-human animals prove that lead exposure causes decreased attention and decreased control over behavior when subjects are startled or touched. The study team reasoned that if exposed children were affected the same way, they would be more likely to engage in disruptive classroom behaviors that could result in suspension. The results of the study supported that hypothesis.”Children exposed to lead don’t get a fair start and it affects them for their whole lives,” adds study coauthor Colleen Moore, a UW-Madison psychology professor emerita affiliated with the Nelson Institute.According to the Centers for Disease Control and Prevention, African-American children are more than twice as likely as whites to have elevated lead levels. The reason, say the researchers, is that African-American children are more likely to live in lower-income neighborhoods and rental housing where lead remains in the buildings and soil, a common situation in major American cities.Moore notes that in the city of Milwaukee, lead abatement orders are currently active in more than 100 residential properties. …

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Eavesdropping plants prepare to be attacked

Aug. 7, 2013 — In a world full of hungry predators, prey animals must be constantly vigilant to avoid getting eaten. But plants face a particular challenge when it comes to defending themselves.”One of the things that makes plants so ecologically interesting is that they can’t run away,” says John Orrock, a zoology professor at the University of Wisconsin-Madison. “You can’t run, you can’t necessarily hide, so what can you do? Some plants make themselves less tasty.”Some do this either by boosting their production of toxic or unpleasant-tasting chemicals (think cyanide, sulfurous compounds, or acids) or through building physical defenses such as thorns or tougher leaves.But, he adds, “Defense is thought to come at a cost. If you’re investing in chemical defenses, that’s energy that you could be putting into growth or reproduction instead.”To balance those costs with survival, it may behoove a plant to be able to assess when danger is nigh and defenses are truly necessary. Previous research has shown that plants can induce defenses against herbivores in response to airborne signals from wounded neighbors.But cues from damaged neighbors may not always be useful, especially for the first plant to be attacked, Orrock says. Instead he asked whether plants — here, black mustard, a common roadside weed — can use other types of cues to anticipate a threat.In a presentation Aug. 6 at the 2013 Ecological Society of America Annual Meeting in Minneapolis, he and co-author Simon Gilroy, a UW-Madison botany professor, reported that the plants can eavesdrop on herbivore cues to mount a defensive response even before any plant is attacked.Slugs and snails are generalist herbivores that love to munch on mustard plants and can’t help but leave evidence of their presence — a trail of slime, or mucus. Where there’s slime, there’s a snail. …

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Borneo’s orangutans are coming down from the trees; Behavior may show adaptation to habitat change

July 29, 2013 — Orangutans might be the king of the swingers, but primatologists in Borneo have found that the great apes spend a surprising amount of time walking on the ground. The research, published in the American Journal of Primatology found that it is common for orangutans to come down from the trees to forage or to travel, a discovery which may have implications for conservation efforts.An expedition led by Brent Loken from Simon Fraser University and Dr. Stephanie Spehar from the University of Wisconsin Oshkosh, travelled to the East Kalimantan region of Borneo. The region’s Wehea Forest is a known biodiversity hotspot for primates, including the Bornean orangutan subspecies, Pongo pygmaeus morio, the least studied of orangutan subspecies.”Orangutans are elusive and one reason why recorded evidence of orangutans on the ground is so rare is that the presence of observers inhibits this behaviour,” said Loken. “However, with camera traps we are offered a behind the scenes glimpse at orangutan behaviour.”The team positioned ground-based cameras across a 38-square-kilometre region of the forest and succeeded in capturing the first evidence of orangutans regularly coming down from the trees. The amount of time orangutans spent on the forest floor was found to be comparable to the ground-dwelling pig-tailed macaque, Macaca nemestrina, which is equally abundant in Wehea Forest. Over 8-months orangutans were photographed 110 times, while the macaques were photographed 113 times.The reason orangutans come down from the trees remains a mystery. However, while the absence of large predators may make it safer to walk on the forest floor, a more pressing influence is the rapid and unprecedented loss of Borneo’s orangutan habitat.”Borneo is a network of timber plantations, agro-forestry areas and mines, with patches of natural forest,” said Loken. “The transformation of the landscape could be forcing orangutans to change their habitat and their behaviour.”This research helps to reveal how orangutans can adapt to their changing landscape; however, this does not suggest they can just walk to new territory if their habitat is destroyed. The orangutan subspecies P. …

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Borneo’s orangutans are coming down from the trees

July 29, 2013 — Orangutans might be the king of the swingers, but primatologists in Borneo have found that the great apes spend a surprising amount of time walking on the ground. The research, published in the American Journal of Primatology found that it is common for orangutans to come down from the trees to forage or to travel, a discovery which may have implications for conservation efforts.An expedition led by Brent Loken from Simon Fraser University and Dr. Stephanie Spehar from the University of Wisconsin Oshkosh, travelled to the East Kalimantan region of Borneo. The region’s Wehea Forest is a known biodiversity hotspot for primates, including the Bornean orangutan subspecies, Pongo pygmaeus morio, the least studied of orangutan subspecies.”Orangutans are elusive and one reason why recorded evidence of orangutans on the ground is so rare is that the presence of observers inhibits this behaviour,” said Loken. “However, with camera traps we are offered a behind the scenes glimpse at orangutan behaviour.”The team positioned ground-based cameras across a 38-square-kilometre region of the forest and succeeded in capturing the first evidence of orangutans regularly coming down from the trees. The amount of time orangutans spent on the forest floor was found to be comparable to the ground-dwelling pig-tailed macaque, Macaca nemestrina, which is equally abundant in Wehea Forest. Over 8-months orangutans were photographed 110 times, while the macaques were photographed 113 times.The reason orangutans come down from the trees remains a mystery. However, while the absence of large predators may make it safer to walk on the forest floor, a more pressing influence is the rapid and unprecedented loss of Borneo’s orangutan habitat.”Borneo is a network of timber plantations, agro-forestry areas and mines, with patches of natural forest,” said Loken. “The transformation of the landscape could be forcing orangutans to change their habitat and their behaviour.”This research helps to reveal how orangutans can adapt to their changing landscape; however, this does not suggest they can just walk to new territory if their habitat is destroyed. The orangutan subspecies P. …

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Distinctive brain blood flow patterns associated with sexual dysfunction

July 16, 2013 — Premenopausal women who aren’t interested in sex and are unhappy about this reality have distinctive blood flow patterns in their brains in response to explicit videos compared to women with normal sexual function, researchers report.A study of 16 women — six with normal sexual function and 10 with clear symptoms of dysfunction — showed distinct differences in activation of brain regions involved in making and retrieving memories, and determining how attentive they are to their response to sexual stimuli, researchers report in the journal Fertility and Sterility.Up to 20 percent of women may have this form of sexual dysfunction, called hypoactive sexual desire disorder, for which there are no proven therapies, said Dr. Michael P. Diamond, Chairman of the Department of Obstetrics and Gynecology at the Medical College of Georgia at Georgia Regents University.Researchers hope that a clearer understanding of physiological differences in these women will provide novel therapy targets as well as a method to objectively assess therapies, said Diamond, the study’s senior author.”There are site-specific alterations in blood flow in the brains of individuals with hypoactive sexual disorders versus those with normal sexual function,” Diamond said. “This tells me there is a physiologic means of assessing hypoactive sexual desire and that as we move forward with therapeutics, whether it’s counseling or medications, we can look to see whether changes occur in those regions.”Viagra, developed in the 1990s as way to increase the heart rate of sick babies, was approved by the Food and Drug Administration in 1998 to also treat male impotence, a major cause of sexual dysfunction. While several more options for men have been developed since, no FDA-approved options are available for women experiencing hypoactive sexual desire, Diamond said. He notes that a possible critical flaw in developing and evaluating therapies for women may be the inability to objectively measure results, other than with a woman’s self-reporting of its impact on sexual activity.Years ago, Diamond, a reproductive endocrinologist, became frustrated by the inability to help these women. In fact, many women did not bother discussing the issue with their physicians, possibly because it’s an awkward problem with no clear solutions, he said.While still at Wayne State University, he and his colleagues began looking for objective measures of a woman’s sexual response, identifying sexually explicit film clips, then using functional magnetic resonance imaging, which measures real-time brain activation in response to a stimulus, to look at responses.Their latest study links acquired hypoactive sexual desire disorder to a distinct pattern of blood flow in the brain, with significant activation of cortical structures involved in attention and reflection about emotion and mental state. Researchers noted that paying more attention to response to sexual stimuli already is implicated in sexual dysfunction. They also note activation of the anterior cingulate gyrus, an area involved in a broad range of emotions including homeostasis, pain, depression, and apathy. Another key area was the amygdala, which has a central role in processing emotion, learning, and memory.Women with normal sexual function showed significantly greater activation of areas such as the right thalamus — a sort of relay station for handling sensory and motor input — that also plays a role in sexual arousal. …

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How cranberries impact infection-causing bacteria

July 15, 2013 — Consuming cranberry products has been anecdotally associated with prevention of urinary tract infections (UTIs) for over 100 years. But is this popular belief a myth, or scientific fact?In recent years, some studies have suggested that cranberries prevent UTIs by hindering bacteria from sticking to the walls of the urinary tract, thanks to phytochemicals known as proanthocyanidins (PACs). Yet the mechanisms by which cranberry materials may alter bacterial behaviour have not been fully understood.Now, researchers in McGill University’s Department of Chemical Engineering are shedding light on the biological mechanisms by which cranberries may impart protective properties against urinary tract and other infections. Two new studies, spearheaded by Prof. Nathalie Tufenkji, add to evidence of cranberries’ effects on UTI-causing bacteria. The findings also point to the potential for cranberry derivatives to be used to prevent bacterial colonization in medical devices such as catheters.In research results published online last month in the Canadian Journal of Microbiology, Prof. Tufenkji and members of her laboratory report that cranberry powder can inhibit the ability of Proteus mirabilis, a bacterium frequently implicated in complicated UTIs, to swarm on agar plates and swim within the agar. The experiments also show that increasing concentrations of cranberry powder reduce the bacteria’s production of urease, an enzyme that contributes to the virulence of infections.These results build on previous work by the McGill lab, showing that cranberry materials hinder movement of other bacteria involved in UTIs. A genome-wide analysis of an uropathogenic E. coli revealed that expression of the gene that encodes for the bacteria’s flagellar filament was decreased in the presence of cranberry PACs.The team’s findings are significant because bacterial movement is a key mechanism for the spread of infection, as infectious bacteria literally swim to disseminate in the urinary tract and to escape the host immune response.”While the effects of cranberry in living organisms remain subject to further study, our findings highlight the role that cranberry consumption might play in the prevention of chronic infections,” Tufenkji says. …

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Test can accurately and swiftly detect most leading causes of bacterial blood stream infections

July 2, 2013 — A new automated diagnostic test can quickly and accurately identify most leading causes of Gram-positive bacterial blood stream infections and the presence of three antibiotic resistance genes, according to a new study published this week in PLOS Medicine. The findings from the study, conducted by a team of researchers led by Nathan Ledeboer from the Medical College of Wisconsin (MCW), USA, suggest that the new technology could lead to faster diagnosis and treatment of patients suffering from sepsis.Share This:Severe sepsis is a life-threatening condition that is usually triggered by a bacterial infection of the bloodstream. In the most severe cases of sepsis multiple organs can fail and in the US alone sepsis causes up to 250,000 deaths a year. The outcome of sepsis is affected by many factors, but fast, accurate identification of the bacterial infection and determination of its antibiotic susceptibility is essential to ensure that patients receive appropriate antibiotics. In the study published this week the researchers evaluated a new test, called Verigene BC-GP, that has been designed to simultaneously detect the DNA of 12 species of Gram-positive bacteria, which are the most common cause of bacterial bloodstream infections, and three antibiotic resistance genes in cultures grown from patient blood samples.The researchers evaluated the Verigene BC-GP test using 1252 blood cultures from five US clinical centers and 397 contrived cultures (that contained rarer bacterial species found in blood stream infections) compared to standard culture techniques. They found that the test was able to correctly identify patients who were positive for a specific infection in 92.6% to 100% of samples and to correctly determine patients that did not have a specific infection in 94.5-100% of samples. However, about 7.5% of cultures contained Gram-positive bacteria that the test was not designed to detect. The researchers also found that the test was able accurately identifying three bacterial resistance genes (the mecA, vanA, and vanB genes), which confer resistance to the antibiotics vancomycin and methicillin. The test takes about 2 hours to run and in an analysis of 107 blood culture broths the researchers found the test was able to return a result about 42 hours faster than the conventional culture methods.The researchers say, “[t]he high sensitivity and specificity characteristics of this test, coupled with on-demand testing capability and a [2 hour turnaround time] enable reporting of both the identification and antimicrobial resistance genes of bacteria obtained from blood culture significantly faster than using routine culture methods.”The faster diagnosis should improve the care of patients with sepsis by allowing physicians to prescribe appropriate antibiotics much earlier than is currently possible.Share this story on Facebook, Twitter, and Google:Other social bookmarking and sharing tools:|Story Source: The above story is reprinted from materials provided by Public Library of Science. Note: Materials may be edited for content and length. …

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New catalyst could cut cost of making hydrogen fuel

July 2, 2013 — A discovery at the University of Wisconsin-Madison may represent a significant advance in the quest to create a “hydrogen economy” that would use this abundant element to store and transfer energy.Theoretically, hydrogen is the ultimate non-carbon, non-polluting fuel for storing intermittent energy from the wind or sun. When burned for energy, hydrogen produces water but no carbon dioxide. Practically speaking, producing hydrogen from water, and then storing and using the gas, have proven difficult.The new study, now published online at the Journal of the American Chemical Society, introduces a new catalyst structure that can facilitate the use of electricity to produce hydrogen gas from water.Significantly, the catalyst avoids the rare, expensive metal platinum that is normally required for this reaction. (Catalysts speed up chemical reactions without themselves being consumed.)The material under study, molybdenum disulfide, contains two common elements, notes Mark Lukowski, a Ph.D. student working with associate professor Song Jin in the UW-Madison chemistry department. “Most people have tried to reduce the cost of the catalyst by making small particles that use less platinum, but here we got rid of the platinum altogether and still got reasonably high performance.”The research group has produced milligram quantities of the catalyst, “but in principle you could scale this up,” says Lukowski. “Molybdenum disulfide is a commercially available product. To control purity and structure, we go through the trouble of synthesizing it from the bottom up, but you could buy it today.”To make the new material, Lukowski and Jin deposit nanostructures of molybdenum disulfide on a disk of graphite and then apply a lithium treatment to create a different structure with different properties.Just as carbon can form diamond for jewelry and graphite for writing, molybdenum disulfide can be a semiconductor or a metallic phase, depending on structure. When the compound is grown on the graphite, it is a semiconductor, but it becomes metallic after the lithium treatment. Lukowski and Jin discovered that the metallic phase has far greater catalytic properties.”Like graphite, which is made up of a stack of sheets that easily separate, molybdenum disulfide is made up of individual sheets that can come apart, and previous studies have shown that the catalytically active sites are located along the edges of the sheets,” says Lukowski.”The lithium treatment both causes the semiconducting-to-metallic phase change and separates the sheets, creating more edges. …

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Antioxidant shows promise in Parkinson’s disease

June 19, 2013 — Diapocynin, a synthetic molecule derived from a naturally occurring compound (apocynin), has been found to protect neurobehavioral function in mice with Parkinson’s Disease symptoms by preventing deficits in motor coordination.The findings are published in the May 28, 2013 edition of Neuroscience Letters.Brian Dranka, PhD, postdoctoral fellow at the Medical College of Wisconsin (MCW), is the first author of the paper. Balaraman Kalyanaraman, PhD, Harry R. & Angeline E. Quadracci Professor in Parkinson’s Research, chairman and professor of biophysics, and director of the MCW Free Radical Research Center, is the corresponding author.In a specific type of transgenic mouse called LRRK2R1441G, the animals lose coordinated movements and develop Parkinson’s-type symptoms by ten months of age. In this study, the researchers treated those mice with diapocynin starting at 12 weeks. That treatment prevented the expected deficits in motor coordination.”These early findings are encouraging, but in this model, we still do not know how this molecule exerts neuroprotective action. Further studies are necessary to discover the exact mode of action of the diaopocynin and other molecules with a similar structure,” said Dr. Kalyanaraman.Clinicians have expressed a need for earlier disease detection in Parkinson’s Disease patients; the researchers believe further study of this specific mouse model may allow them to identify new biomarkers that would enable early disease detection, and ultimately allow for better patient care and quality of life.Other authors of the paper include Joy Joseph, PhD, associate professor of biophysics; Jacek Zielonka, PhD, research scientist; and Allison Gifford, research technologist, all of MCW; Anumantha Kanthasamy, MS, M.Phil, PhD, W.E. Lloyd Endowed Chair in Neurotoxicology and chair of the biomedical sciences department and distinguished professor; and Anamitra Ghosh, research fellow; both of the Iowa State University College of Veterinary Medicine. This research was funded by NIH grants NS039958 (to B.K.) and NS074443 (to A.K.), and by the Henry R. …

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A step closer to artificial livers: Researchers identify compounds that help liver cells grow outside body

June 2, 2013 — Prometheus, the mythological figure who stole fire from the gods, was punished for this theft by being bound to a rock. Each day, an eagle swept down and fed on his liver, which then grew back to be eaten again the next day.Modern scientists know there is a grain of truth to the tale, says MIT engineer Sangeeta Bhatia: The liver can indeed regenerate itself if part of it is removed. However, researchers trying to exploit that ability in hopes of producing artificial liver tissue for transplantation have repeatedly been stymied: Mature liver cells, known as hepatocytes, quickly lose their normal function when removed from the body.”It’s a paradox because we know liver cells are capable of growing, but somehow we can’t get them to grow” outside the body, says Bhatia, the John and Dorothy Wilson Professor of Health Sciences and Technology and Electrical Engineering and Computer Science at MIT, a senior associate member of the Broad Institute and a member of MIT’s Koch Institute for Integrative Cancer Research and Institute for Medical Engineering and Science.Now, Bhatia and colleagues have taken a step toward that goal. In a paper appearing in the June 2 issue of Nature Chemical Biology, they have identified a dozen chemical compounds that can help liver cells not only maintain their normal function while grown in a lab dish, but also multiply to produce new tissue.Cells grown this way could help researchers develop engineered tissue to treat many of the 500 million people suffering from chronic liver diseases such as hepatitis C, according to the researchers.Lead author of the paper is Jing (Meghan) Shan, a graduate student in the Harvard-MIT Division of Health Sciences and Technology. Members of Bhatia’s lab collaborated with researchers from the Broad Institute, Harvard Medical School and the University of Wisconsin.Large-scale screenBhatia has previously developed a way to temporarily maintain normal liver-cell function after those cells are removed from the body, by precisely intermingling them with mouse fibroblast cells. For this study, funded by the National Institutes of Health and Howard Hughes Medical Institute, the research team adapted the system so that the liver cells could grow, in layers with the fibroblast cells, in small depressions in a lab dish. This allowed the researchers to perform large-scale, rapid studies of how 12,500 different chemicals affect liver-cell growth and function.The liver has about 500 functions, divided into four general categories: drug detoxification, energy metabolism, protein synthesis and bile production. David Thomas, an associate researcher working with Todd Golub at the Broad Institute, measured expression levels of 83 liver enzymes representing some of the most finicky functions to maintain.After screening thousands of liver cells from eight different tissue donors, the researchers identified 12 compounds that helped the cells maintain those functions, promoted liver cell division, or both.Two of those compounds seemed to work especially well in cells from younger donors, so the researchers — including Robert Schwartz, an IMES postdoc, and Stephen Duncan, a professor of human and molecular genetics at the University of Wisconsin — also tested them in liver cells generated from induced pluripotent stem cells (iPSCs). Scientists have tried to create hepatocytes from iPSCs before, but such cells don’t usually reach a fully mature state. However, when treated with those two compounds, the cells matured more completely.Bhatia and her team wonder whether these compounds might launch a universal maturation program that could influence other types of cells as well. …

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