New EMS system dramatically improves survival from cardiac arrest

A new system that sent patients to designated cardiac receiving centers dramatically increased the survival rate of victims of sudden cardiac arrest in Arizona, according to a study published online in Annals of Emergency Medicine.”We knew lives would be saved if the hospitals implemented the latest cutting edge guidelines for post-cardiac arrest care and we were able to get cardiac arrest patients to those hospitals, similar to what is done for Level 1 trauma patients,” said lead study author Daniel Spaite, MD, Director of EMS Research at the University of Arizona Emergency Medicine Research Center in Phoenix and Tucson and a professor and distinguished chair of emergency medicine at the University of Arizona College of Medicine. “Taking these patients directly to a hospital optimally prepared to treat cardiac arrest gave patients a better chance of survival and of preventing neurologic damage, a common result of these cardiac events.”Under the study, 31 hospitals, serving about 80 percent of the state’s population, were designated as cardiac receiving centers between December 2007 and November 2010. Approximately 55 emergency medicine service agencies also participated in the study.The study shows that the survival rate increased by more than 60 percent during the four-year period of the study, from 2007 to 2010. More importantly, when the results were adjusted for the various factors that significantly impact survival (such as age and how quickly the EMS system got to the patients after their arrest), the likelihood of surviving an arrest more than doubled. In addition, the likelihood of surviving with good neurological status also more than doubled.This statewide effort was accomplished through the Save Hearts Arizona Registry and Education-SHARE Program, a partnership involving the Arizona Department of Health Services, the University of Arizona, over 30 hospitals and more than 100 fire departments and EMS agencies. The SHARE Program is part of a network of statewide cardiac resuscitation programs dedicated to improving cardiac arrest survival and working together as the HeartRescue Project.”We worked closely with the hospitals around the state to implement these Guidelines and then formally recognized the hospitals as Cardiac Receiving Centers (CRCs) ,” said Ben Bobrow, MD, Medical Director of the Bureau of Emergency Medicine Services and Trauma System for the Arizona Department of Health Services in Phoenix, Ariz. “We then developed protocols for our EMS agencies to transport post-cardiac arrest patients to those centers. Our overarching goal was to have more cardiac arrest victims leave the hospital in good shape and be able to return to their families and careers. As we suspected, ‘regionalizing’ the care for these critically-ill patients markedly increased their likelihood of survival and good neurologic outcome.”Dr. Bobrow, who is also a professor of emergency medicine at the University of Arizona College of Medicine-Phoenix and an emergency physician at Maricopa Medical Center, said the study shows that just transporting these patients to the nearest emergency department does not maximize the likelihood of a positive outcome. …

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Daylight saving impacts timing of heart attacks

Still feeling the residual effects of springing ahead for daylight saving time? The hour of sleep lost — or gained — may play a bigger, perhaps more dangerous role in our body’s natural rhythm than we think. It seems moving the clock forward or backward may alter the timing of when heart attacks occur in the week following these time changes, according to research to be presented at the American College of Cardiology’s 63rd Annual Scientific Session.Data from the largest study of its kind in the U.S. reveal a 25 percent jump in the number of heart attacks occurring the Monday after we “spring forward” compared to other Mondays during the year — a trend that remained even after accounting for seasonal variations in these events. But the study showed the opposite effect is also true. Researchers found a 21 percent drop in the number of heart attacks on the Tuesday after returning to standard time in the fall when we gain an hour back.”What’s interesting is that the total number of heart attacks didn’t change the week after daylight saving time,” said Amneet Sandhu, M.D., cardiology fellow, University of Colorado in Denver, and lead investigator of the study. “But these events were much more frequent the Monday after the spring time change and then tapered off over the other days of the week. It may mean that people who are already vulnerable to heart disease may be at greater risk right after sudden time changes.”Heart attacks historically occur most often on Monday mornings. Sandhu explains that in looking at other “normal” Mondays, there is some variation in events, but it is not significant. However, when he and his team compared admissions from a database of non-federal Michigan hospitals the Monday before the start of daylight saving time and the Monday immediately after for four consecutive years, they found a consistent 34 percent increase in heart attacks from one week to the next (93 heart attacks the Monday before compared to 125 the week after the start of daylight saving time for the duration of the study.).Although researchers cannot say what might be driving the shift in heart attack timing after the start of daylight saving time, they have a theory.”Perhaps the reason we see more heart attacks on Monday mornings is a combination of factors, including the stress of starting a new work week and inherent changes in our sleep-wake cycle,” Sandhu said. …

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Hubble witnesses an asteroid mysteriously disintegrating

The NASA/ESA Hubble Space Telescope has photographed the never-before-seen break-up of an asteroid, which has fragmented into as many as ten smaller pieces. Although fragile comet nuclei have been seen to fall apart as they approach the Sun, nothing like the breakup of this asteroid, P/2013 R3, has ever been observed before in the asteroid belt.”This is a rock. Seeing it fall apart before our eyes is pretty amazing,” said David Jewitt of UCLA, USA, who led the astronomical forensics investigation.The crumbling asteroid, designated P/2013 R3, was first noticed as an unusual, fuzzy-looking object on 15 September 2013 by the Catalina and Pan-STARRS sky surveys. Follow-up observations on 1 October with the Keck Telescope on Mauna Kea, Hawaii, revealed three co-moving bodies embedded in a dusty envelope that is nearly the diameter of Earth.”Keck showed us that this thing was worth looking at with Hubble,” Jewitt said. With its superior resolution, the space-based Hubble observations soon showed that there were really ten distinct objects, each with comet-like dust tails. The four largest rocky fragments are up to 200 metres in radius, about twice the length of a football pitch.The Hubble data showed that the fragments are drifting away from each other at a leisurely 1.5 kilometres per hour — slower than the speed of a strolling human. The asteroid began coming apart early last year, but the latest images show that pieces continue to emerge.”This is a really bizarre thing to observe — we’ve never seen anything like it before,” says co-author Jessica Agarwal of the Max Planck Institute for Solar System Research, Germany. “The break-up could have many different causes, but the Hubble observations are detailed enough that we can actually pinpoint the process responsible.”The ongoing discovery of more fragments makes it unlikely that the asteroid is disintegrating due to a collision with another asteroid, which would be instantaneous and violent in comparison to what has been observed. Some of the debris from such a high-velocity smash-up would also be expected to travel much faster than has been observed.It is also unlikely that the asteroid is breaking apart due to the pressure of interior ices warming and vaporising. The object is too cold for ices to significantly sublimate, and it has presumably maintained its nearly 480-million-kilometre distance from the Sun for much of the age of the Solar System.This leaves a scenario in which the asteroid is disintegrating due to a subtle effect of sunlight that causes the rotation rate to slowly increase over time. …

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Promising cervical cancer study: Combining drugs, chemo to extend life

Research on cervical cancer performed by a physician at the University of Arizona Cancer Center at St. Joseph’s Hospital and Medical Center has been published in the New England Journal of Medicine. The multi-site research project by Bradley J. Monk, MD, is expected to change the standard of care for women with advanced cervical cancer.The featured research revealed that women with advanced cervical cancer live about four months longer with the combined use of bevacizumab (Avastin) and chemotherapy compared to chemotherapy alone. Women who combined bevacizumab with chemotherapy lived an average of 17 months after diagnosis, while those who received chemotherapy alone lived 13.3 months.”This research proves that there are new options for patients with metastatic cervical cancer,” says Dr. Monk, the project’s senior author. “I predict that adding bevacizumab to chemotherapy will become the new standard of care.” Dr. Monk is nationally recognized for his expertise in cervical cancer and chairs the Gynecologic Oncology Cervical Cancer Committee for the National Cancer Institute funded Gynecologic Oncology Group. Krishnansu S. Tewari, MD, at the University of California Irvine was the first author on the study published online February 20 in the Journal.The research was conducted between April 2009 and January 2012. …

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Artificial leaf jumps developmental hurdle

In a recent early online edition of Nature Chemistry, ASU scientists, along with colleagues at Argonne National Laboratory, report advances toward perfecting a functional artificial leaf.Designing an artificial leaf that uses solar energy to convert water cheaply and efficiently into hydrogen and oxygen is one of the goals of BISfuel — the Energy Frontier Research Center, funded by the Department of Energy, in the Department of Chemistry and Biochemistry at Arizona State University.Hydrogen is an important fuel in itself and serves as an indispensible reagent for the production of light hydrocarbon fuels from heavy petroleum feed stocks. Society requires a renewable source of fuel that is widely distributed, abundant, inexpensive and environmentally clean.Society needs cheap hydrogen.”Initially, our artificial leaf did not work very well, and our diagnostic studies on why indicated that a step where a fast chemical reaction had to interact with a slow chemical reaction was not efficient,” said ASU chemistry professor Thomas Moore. “The fast one is the step where light energy is converted to chemical energy, and the slow one is the step where the chemical energy is used to convert water into its elements viz. hydrogen and oxygen.”The researchers took a closer look at how nature had overcome a related problem in the part of the photosynthetic process where water is oxidized to yield oxygen.”We looked in detail and found that nature had used an intermediate step,” said Moore. “This intermediate step involved a relay for electrons in which one half of the relay interacted with the fast step in an optimal way to satisfy it, and the other half of the relay then had time to do the slow step of water oxidation in an efficient way.”They then designed an artificial relay based on the natural one and were rewarded with a major improvement.Seeking to understand what they had achieved, the team then looked in detail at the atomic level to figure out how this might work. They used X-ray crystallography and optical and magnetic resonance spectroscopy techniques to determine the local electromagnetic environment of the electrons and protons participating in the relay, and with the help of theory (proton coupled electron transfer mechanism), identified a unique structural feature of the relay. This was an unusually short bond between a hydrogen atom and a nitrogen atom that facilitates the correct working of the relay.They also found subtle magnetic features of the electronic structure of the artificial relay that mirrored those found in the natural system.Not only has the artificial system been improved, but the team understands better how the natural system works. This will be important as scientists develop the artificial leaf approach to sustainably harnessing the solar energy needed to provide the food, fuel and fiber that human needs are increasingly demanding.ASU chemistry professors involved in this specific project include Thomas Moore, Devens Gust, Ana Moore and Vladimiro Mujica. The department is a unit of the College of Liberal Arts and Sciences. Key collaborators in this work are Oleg Poluektov and Tijana Rajh from Argonne National Laboratory.This work would not have been possible without the participation of many scientists driven by a common goal and coordinated by a program such as the Energy Frontier Research Center to bring the right combination of high-level skills to the research table.The Department of Chemisry and Biocehmistry is an academic unit in ASU’s College of Liberal Arts and Sciences.Story Source:The above story is based on materials provided by Arizona State University College of Liberal Arts and Sciences. …

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Study on flu evolution may change textbooks, history books

A new study reconstructing the evolutionary tree of flu viruses challenges conventional wisdom and solves some of the mysteries surrounding flu outbreaks of historical significance.The study, published in the journal Nature, provides the most comprehensive analysis to date of the evolutionary relationships of influenza virus across different host species over time. In addition to dissecting how the virus evolves at different rates in different host species, the study challenges several tenets of conventional wisdom, for example the notion that the virus moves largely unidirectionally from wild birds to domestic birds rather than with spillover in the other direction. It also helps resolve the origin of the virus that caused the unprecedentedly severe influenza pandemic of 1918.The new research is likely to change how scientists and health experts look at the history of influenza virus, how it has changed genetically over time and how it has jumped between different host species. The findings may have implications ranging from the assessment of health risks for populations to developing vaccines.”We now have a really clear family tree of theses viruses in all those hosts — including birds, humans, horses, pigs — and once you have that, it changes the picture of how this virus evolved,” said Michael Worobey, a professor of ecology and evolutionary biology at the University of Arizona, who co-led the study with Andrew Rambaut, a professor at the Institute of Evolutionary Biology at the University of Edinburgh. “The approach we developed works much better at resolving the true evolution and history than anything that has previously been used.”Worobey explained that “if you don’t account for the fact that the virus evolves at a different rates in each host species, you can get nonsense — nonsensical results about when and from where pandemic viruses emerged.””Once you resolve the evolutionary trees for these viruses correctly, everything snaps into place and makes much more sense,” Worobey said, adding that the study originated at his kitchen table.”I had a bunch of those evolutionary trees printed out on paper in front of me and started measuring the lengths of the branches with my daughter’s plastic ruler that happened to be on the table. Just like branches on a real tree, you can see that the branches on the evolutionary tree grow at different rates in humans versus horses versus birds. And I had a glimmer of an idea that this would be important for our public health inferences about where these viruses come from and how they evolve.””My longtime collaborator Andrew Rambaut implemented in the computer what I had been doing with a plastic ruler. We developed software that allows the clock to tick at different rates in different host species. Once we had that, it produces these very clear and clean results.”The team analyzed a dataset with more than 80,000 gene sequences representing the global diversity of the influenza A virus and analyzed them with their newly developed approach. The influenza A virus is subdivided into 17 so-called HA subtypes — H1 through H17 — and 10 subtypes of NA, N1-N10. …

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Geographic variation of human gut microbes tied to obesity

People living in cold, northern latitudes have bacteria in their guts that may predispose them to obesity, according to a new study by researchers at the University of California, Berkeley, and the University of Arizona, Tucson.The researchers’ analysis of the gut microbes of more than a thousand people from around the world showed that those living in northern latitudes had more gut bacteria that have been linked to obesity than did people living farther south.The meta-analysis of six earlier studies was published this month in the online journal Biology Letters by UC Berkeley graduate student Taichi Suzuki and evolutionary biology professor Michael Worobey of the University of Arizona.”People think obesity is a bad thing, but maybe in the past getting more fat and more energy from the diet might have been important to survival in cold places. Our gut microbes today might be influenced by our ancestors,” said Suzuki, noting that one theory is that obesity-linked bacteria are better at extracting energy from food. “This suggests that what we call ‘healthy microbiota’ may differ in different geographic regions.””This observation is pretty cool, but it is not clear why we are seeing the relationship we do with latitude,” Worobey said. “There is something amazing and weird going on with microbiomes.”To Worobey, the results are fascinating from an evolutionary biology perspective. “Maybe changes to your gut community of bacteria are important for allowing populations to adapt to different environmental conditions in lots of animals, including humans,” he said.Body size increases with latitudeSuzuki proposed the study while rotating through Worobey’s lab during his first year as a graduate student at the University of Arizona. Studies of gut microbes have become a hot research area among scientists because the proportion of different types of bacteria and Archaea in the gut seems to be correlated with diseases ranging from diabetes and obesity to cancer. In particular, the group of bacteria called Firmicutes seems to dominate in the intestines of obese people — and obese mice — while a group called Bacteroidetes dominates in slimmer people and mice.Suzuki reasoned that, since animals and humans in the north tend to be larger in size — an observation called Bergmann’s rule — then perhaps their gut microbiota would contain a greater proportion of Firmicutes than Bacteriodetes. While at the University of Arizona, and since moving to UC Berkeley, Suzuki has been studying how rodents adapt to living at different latitudes.”It was almost as a lark,” Woroby said. “Taichi thought that if Firmicutes and Bacteroidetes are linked to obesity, why not look at large scale trends in humans. When he came back with results that really showed there was something to it, it was quite a surprise.”Suzuki used data published in six previous studies, totaling 1,020 people from 23 populations in Africa, Europe, North and South America and Asia. …

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Humans, urban landscapes increase illness in songbirds, researchers find

Humans living in densely populated urban areas have a profound impact not only on their physical environment, but also on the health and fitness of native wildlife. For the first time, scientists have found a direct link between the degree of urbanization and the prevalence and severity of two distinct parasites in wild house finches.The findings are published in the Feb. 4 issue of the journal PLOS ONE.A team of researchers from Arizona State University made the discovery while investigating intestinal parasites (Isospora sp.) and the canarypox virus (Avipoxvirus) found in house finches. The group also studied the effects of urbanization on the stress response system of the finches.Specifically, the team studied male house finches found at seven sites throughout Maricopa County in central Arizona. Each site varied in the number of people living within one kilometer (about five-eighths of a mile) — from nearly a dozen to over 17 thousand.Researchers also considered whether the soil in each location had been disturbed and the vegetation cultivated or left in a natural state. In all, they quantified 13 different urbanization factors. They also assessed the potential relationship between oxidative stress, the degree of urbanization and parasitic infections to see whether increased infections are associated with increased stress levels.”Several studies have measured parasite infection in urban animals, but surprisingly we are the first to measure whether wild birds living in a city were more or less infected by a parasite and a pathogen, as well as how these infections are linked to their physiological stress,” said Mathieu Giraudeau, a post-doctoral associate who previously worked with Kevin McGraw, ASU associate professor with the School of Life Sciences. Giraudeau now works with the University of Zurich in Switzerland.”We also capitalized on data gathered by the Central Arizona Phoenix-Long Term Ecological Research program to accurately measure the degree to which the landscapes at each study site were natural or disturbed by humans,” added Giraudeau.House finches (Haemorhous mexicanus) are native to the desert southwest in the U.S., but are now found abundantly throughout North America. Male finches are five to six inches long and have colorful red, orange or yellow crown, breast and rump feathers.Emerging infectious diseases transmitted from animals to humansAccording to the study, more than half of the world’s population now lives in cities. Natural habitats and ecosystems have been dramatically altered from their original states, and there is rising concern about the spread of diseases that can be passed from urban wildlife to humans. …

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Drug trafficking leads to deforestation in Central America

Add yet another threat to the list of problems facing the rapidly disappearing rainforests of Central America: drug trafficking.In an article in the journal Science, seven researchers who have done work in Central America point to growing evidence that drug trafficking threatens forests in remote areas of Honduras, Guatemala, Nicaragua and nearby countries.Traffickers are slashing down forests, often within protected areas, to make way for clandestine landing strips and roads to move drugs, and converting forests into agribusinesses to launder their drug profits, the researchers say.Much of this appears to be a response to U.S.-led anti-trafficking efforts, especially in Mexico, said Kendra McSweeney, lead author of the Science article and an associate professor of geography at The Ohio State University.”In response to the crackdown in Mexico, drug traffickers began moving south into Central America around 2007 to find new routes through remote areas to move their drugs from South America and get them to the United States,” McSweeney said.”When drug traffickers moved in, they brought ecological devastation with them.”For example, the researchers found that the amount of new deforestation per year more than quadrupled in Honduras between 2007 and 2011 — the same period when cocaine movements in the country also spiked.McSweeney is a geographer who has done research in Honduras for more than 20 years, studying how indigenous people interact with their environment. The drug trade is not something she would normally investigate, but it has been impossible to ignore in recent years, she said.”Starting about 2007, we started seeing rates of deforestation there that we had never seen before. When we asked the local people the reason, they would tell us: “los narcos” (drug traffickers).”There were other indications of drug trafficking taking place in the area.”I would get approached by people who wanted to change $20 bills in places where cash is very scarce and dollars are not the normal currency. When that starts happening, you know narcos are there,” she said.When McSweeney talked to other researchers in Central America, they had similar stories.”The emerging impacts of narco-trafficking were being mentioned among people who worked in Central America, but usually just as a side conversation. We heard the same kinds of things from agricultural specialists, geographers, conservationists. Several of us decided we needed to bring more attention to this issue.”In the Science article, McSweeney and her co-authors say deforestation starts with the clandestine roads and landing strips that traffickers create in the remote forests. The infusion of drug cash into these areas helps embolden resident ranchers, land speculators and timber traffickers to expand their activities, primarily at the expense of the indigenous people who are often key forest defenders.In addition, the drug traffickers themselves convert forest to agriculture as a way to launder their money. While much of this land conversion occurs within protected areas and is therefore illegal, drug traffickers often use their profits to influence government leaders to look the other way.McSweeney said more research is needed to examine the links between drug trafficking and conservation issues. But there is already enough evidence to show that U.S. drug policy has a much wider effect than is often realized.”Drug policies are also conservation policies, whether we realize it or not,” McSweeney said.”U.S.-led militarized interdiction, for example, has succeeded mainly in moving traffickers around, driving them to operate in ever-more remote, biodiverse ecosystems. …

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Rings, dark side of Saturn glow in new Cassini image

Oct. 21, 2013 — The gauzy rings of Saturn and the dark side of the planet glow in newly released infrared images obtained by NASA’s Cassini spacecraft.”Looking at the Saturn system when it is backlit by the sun gives scientists a kind of inside-out view of Saturn that we don’t normally see,” said Matt Hedman, a participating scientist based at the University of Idaho, Moscow, Idaho. “The parts of Saturn’s rings that are bright when you look at them from backyard telescopes on Earth are dark, and other parts that are typically dark glow brightly in this view.”It can be difficult for scientists to get a good look at the faint outer F, E and G rings, or the tenuous inner ring known as the D ring when light is shining directly on them. That’s because they are almost transparent and composed of small particles that do not reflect light well. What’s different about this viewing geometry?When these small particles are lit from behind, they show up like fog in the headlights of an oncoming vehicle. The C ring also appears relatively bright here; not because it is made of dust, but because the material in it — mostly dirty water ice — is translucent. In fact, in the 18th and 19th centuries, it was known as the “crepe ring” because of its supposed similarity to crepe paper. The wide, middle ring known as the B ring — one of the easiest to see from Earth through telescopes because it is densely packed with chunks of bright water ice — looks dark in these images because it is so thick that it blocks almost all of the sunlight shining behind it. Infrared images also show thermal, or heat, radiation. While a visible-light image from this vantage point would simply show the face of the planet as dimly lit by sunlight reflected off the rings, Saturn glows brightly in this view because of heat from Saturn’s interior.In a second version of the image, scientists “stretched” or exaggerated the contrast of the data, which brings out subtleties not initially visible.Structures in the wispy E ring — made from the icy breath of the moon Enceladus — reveal themselves in this exaggerated view. …

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Beware: Flesh Rotting Street Drug "Krokodil"

Krokodil Drug – May Have Come From Russia to the US Over a year ago the nation was shocked by the synthetic drug known as bath salts that was suspected in a horrific act of violence in Miami, Florida. Since then there have been national crackdowns on head shops and gas stations that sold the synthetic drug and news reports of it have dwindled. Last week a new drug, that proves just as, if not more, horrifying than bath salts may have hit the streets in the US.The drug is called “krokodil” because it causes users to break out in scaly sores like a crocodile. These sores aren’t a result of picking, as with meth addicts but from contaminants in the drug that cause human flesh to…

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Effects of climate change on West Nile virus

Sep. 9, 2013 — The varied influence of climate change on temperature and precipitation may have an equally wide-ranging effect on the spread of West Nile virus, suggesting that public health efforts to control the virus will need to take a local rather than global perspective, according to a study published this week in the scientific journal Proceedings of the National Academy of Sciences.University of Arizona researchers Cory Morin and Andrew Comrie developed a climate-driven mosquito population model to simulate the abundance across the southern United States of one type of mosquito known to carry and spread West Nile virus to humans. They found that, under the future climate conditions predicted by climate change models, many locations will see a lengthening of the mosquito season but shrinking summer mosquito populations due to hotter and dryer conditions allowing fewer larvae to survive.However, these changes vary significantly depending on temperature and precipitation. For example, drops in summer mosquito populations are expected to be significant in the South, but not further north where there will still be enough rain to maintain summer breeding habitats and extreme temperatures are less common. These findings suggest that disease transmission studies and programs designed to control populations of disease-carrying mosquitoes must be targeted locally to maximize their effectiveness, the authors argue.”It used to be an open question whether climate change is going to make disease-carrying mosquitoes more abundant, and the answer is it will depend on the time and the location,” said Morin, who did the study as part of his doctoral dissertation in the lab of Comrie, UA provost and professor in the UA’s School of Geography and Development. Morin is now a postdoctoral researcher on Comrie’s team.”One assumption was that with rising temperatures, mosquitoes would thrive across the board,” Morin said. “Our study shows this is unlikely. Rather, the effects of climate change are different depending on the region and because of that, the response of West Nile virus transmitting mosquito populations will be different as well.””The mosquito species we study is subtropical, and at warmer temperatures the larvae develop faster,” Morin explained. “However, there is a limit — if temperatures climb over that limit, mortality increases. Temperature, precipitation or both can limit the populations, depending on local conditions.”In the southwestern U.S. …

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Spider venom reveals new secret: Once injected into a bite wound, venom of brown recluse spider causes unexpected reaction

Aug. 29, 2013 — Venom of the brown recluse spider causes a reaction in the body that is different from what researchers previously thought, a discovery that could lead to development of new treatments for spider bites.University of Arizona researchers led a team that has discovered that venom of spiders in the genus Loxosceles, which contains about 100 spider species including the brown recluse, produces a different chemical product in the human body than scientists believed.The finding has implications for understanding how these spider bites affect humans and for the development of possible treatments for the bites.One of few common spiders whose bites can have a seriously harmful effect on humans, the brown recluse has venom that contains a rare protein that can cause a blackened lesion at the site of a bite, or a much less common, but more dangerous, systemic reaction in humans.”This is not a protein that is usually found in the venom of poisonous animals,” said Matthew Cordes, an associate professor in the UA’s department of chemistry and biochemistry and member of the UA BIO5 Institute who led the study, published today in the journal PLOS ONE.The protein, once injected into a bite wound, attacks phospholipid molecules that are the major component of cell membranes. The protein acts to cleave off the head portion of the lipids, leaving behind, scientists long have assumed, a simple, linear, headless lipid molecule.The research team has discovered that in the test tube, the venom protein causes lipids to bend into a ring structure upon the loss of the head portion, generating a cyclical chemical product that is very different than the linear molecule it was assumed to produce.”The very first step of this whole process that leads to skin and tissue damage or systemic effects is not what we all thought it was,” Cordes said.The lipid knocks off its own head by making a ring within itself, prompted by the protein from the spider venom, Cordes explained. “Part of the outcome of the reaction, the release of the head group, is the same. So initially scientists believed that this was all that was happening, then that became established in the literature.”The research team includes Cordes; Vahe Bandarian, an associate professor also in the UA’s department of chemistry and biochemistry; and Greta Binford, an associate professor of biology at Lewis and Clark College in Portland, Ore. who, completed her doctorate and a postdoc at the UA.Cordes, Bandarian and Daniel Lajoie, a PhD candidate in Cordes’s lab, tested venom from three species of brown recluse spiders from North and South America. Binford, an arachnologist who has traveled the world in search of the eight-legged creatures, collected the spiders, isolated their DNA and milked their venom, which was then frozen and shipped to the UA labs for analysis.”We didn’t find what we thought we were going to find,” Cordes added. “We found something more interesting.”The cyclical shape of the headless molecule means that it has different chemical properties than the linear headless lipid believed to be generated by the protein, Cordes explained. The biological effects of either molecule in human membranes or insects aren’t completely known, he said, but they are likely to be very different.”We think it’s something about that ring product generated by this protein that activates the immune system,” Binford said.”The properties of this cyclic molecule aren’t well-known yet, but knowing that it’s being produced by toxins in venoms might heighten interest,” Cordes said. “Knowing how the protein is actually working and making this cyclic molecule could also lead to better insights on how to inhibit that protein.”For those who do have a reaction to the venom, the most common response is inflammation that after one to two days can develop into a dark lesion surrounding the bite site. …

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How sleep helps brain learn motor task

Aug. 20, 2013 — Sleep helps the brain consolidate what we’ve learned, but scientists have struggled to determine what goes on in the brain to make that happen for different kinds of learned tasks. In a new study, researchers pinpoint the brainwave frequencies and brain region associated with sleep-enhanced learning of a sequential finger tapping task akin to typing, or playing piano.You take your piano lesson, you go to sleep and when you wake up your fingers are better able to play that beautiful sequence of notes. How does sleep make that difference? A new study helps to explain what happens in your brain during those fateful, restful hours when motor learning takes hold.”The mechanisms of memory consolidations regarding motor memory learning were still uncertain until now,” said Masako Tamaki, a postdoctoral researcher at Brown University and lead author of the study that appears Aug. 21 in the Journal of Neuroscience. “We were trying to figure out which part of the brain is doing what during sleep, independent of what goes on during wakefulness. We were trying to figure out the specific role of sleep.”In part because it employed three different kinds of brain scans, the research is the first to precisely quantify changes among certain brainwaves and the exact location of that changed brain activity in subjects as they slept after learning a sequential finger-tapping task. The task was a sequence of key punches that is cognitively akin to typing or playing the piano.Cap of SensorsIn a sleep lab on Brown’s campus researchers use now using caps of EEG sensors in studies of how the brain works to consolidate learning visual tasks. Here graduate student Aaron Berard models the cap.Specifically, the results of complex experiments performed at Massachusetts General Hospital and then analyzed at Brown show that the improved speed and accuracy volunteers showed on the task after a few hours sleep was significantly associated with changes in fast-sigma and delta brainwave oscillations in their supplementary motor area (SMA), a region on the top-middle of the brain. …

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Explosion illuminates invisible galaxy in the dark ages

Aug. 6, 2013 — More than 12 billion years ago a star exploded, ripping itself apart and blasting its remains outward in twin jets at nearly the speed of light. At its death it glowed so brightly that it outshone its entire galaxy by a million times. This brilliant flash traveled across space for 12.7 billion years to a planet that hadn’t even existed at the time of the explosion — our Earth. By analyzing this light, astronomers learned about a galaxy that was otherwise too small, faint and far away for even the Hubble Space Telescope to see.”This star lived at a very interesting time, the so-called dark ages just a billion years after the Big Bang,” says lead author Ryan Chornock of the Harvard-Smithsonian Center for Astrophysics (CfA).”In a sense, we’re forensic scientists investigating the death of a star and the life of a galaxy in the earliest phases of cosmic time,” he adds.The star announced its death with a flash of gamma rays, an event known as a gamma-ray burst (GRB). GRB 130606A was classified as a long GRB since the burst lasted for more than four minutes. It was detected by NASA’s Swift spacecraft on June 6th. Chornock and his team quickly organized follow-up observations by the MMT Telescope in Arizona and the Gemini North telescope in Hawaii.”We were able to get right on target in a matter of hours,” Chornock says. “That speed was crucial in detecting and studying the afterglow.”A GRB afterglow occurs when jets from the burst slam into surrounding gas, sweeping that material up like a snowplow, heating it, and causing it to glow. As the afterglow’s light travels through the dead star’s host galaxy, it passes through clouds of interstellar gas. …

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Extreme wildfires in Western U.S. likely fueled by climate change

Aug. 1, 2013 — Climate change is likely fueling the larger and more destructive wildfires that are scorching vast areas of the American West, according to new research led by Michigan State University scientists.These erratic fires are harder to contain and often result in catastrophic damage and loss of property and life. Although not analyzed in the study, the recent Arizona wildfire that began with a lightning strike and killed 19 firefighters appeared to be such an unpredictable, fast-spreading blaze, according to a state report.The MSU-led study, which appears in the Journal of Applied Meteorology and Climatology, predicts the trend will continue in the western United States.”Our findings suggest that future lower atmospheric conditions may favor larger and more extreme wildfires, posing an additional challenge to fire and forest management,” said Lifeng Luo, MSU assistant professor of geography and lead author on the study.The researchers analyzed current and future climate patterns projected by multiple regional climate models and their effect on the spread of fire in a mountainous region that includes Arizona, Idaho, Nevada, New Mexico, Utah and Wyoming. The study focused on August, the most active month for wildfires in the western United States.August 2012 saw 3.6 million acres burn in the region, the most of any August since 2000. However, there were only 6,948 fires in August 2012 — the second fewest in that 12-year timeframe — meaning the fires were much larger.Large wildfires are mainly driven by natural factors including the availability of fuel (vegetation), precipitation, wind and the location of lightning strikes. In particular, the researchers found that exceptionally dry and unstable conditions in the earth’s lower atmosphere will continue contributing to “erratic and extreme fire behavior.””Global climate change may have a significant impact on these factors, thus affecting potential wildfire activity across many parts of the world,” the study says.Co-authors include Ying Tang and Shiyuan Zhong from MSU, and Xindu Bian and Warren Heilman from the USDA Forest Service.

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Learning from a virus: Keeping genes under wraps

July 30, 2013 — An international collaboration of researchers including Felicia Goodrum of the University of Arizona’s immunobiology department has studied how a human herpes virus carried by the majority of the population packages its genetic information during infection.The discoveries improve the chances of developing more targeted therapies in place of existing drugs, which do not always work or come with side effects.Experts estimate that 60 to 90 percent of the world’s population carry the human cytomegalovirus, or CMV, which is one of the eight herpes viruses that infect humans.In healthy individuals, the virus lies dormant and does not cause overt disease. However, it poses a significant risk when contracted by unborn children — whose immune system has not matured yet — and individuals with compromised immune function.CMV is the leading cause of birth defects resulting from any infectious agent. It affects one in 150 births in the US and most commonly results in hearing loss, but can also cause cognitive or physical anomalies and cerebral palsy. Once infected, the virus stays in the body for life and flares up only when the immune system is suppressed, for example in AIDS patients, transplant patients and cancer patients undergoing intensive chemotherapy.For the study, published in the scientific journal Proceedings of the National Academy of Sciences (PNAS), Goodrum teamed up with collaborators in Germany and Israel.The researchers investigated how a fundamental aspect of the human cell regulates the virus: the mechanism by which genetic information is packaged and stored. Understanding how the viral DNA behaves in the human host cells during dormancy and reactivation of the virus provides the basis for the development of drugs that could prevent the virus from “waking up” and causing disease.”The human immune system is very sophisticated, and the way this virus has managed to stealthily integrate into our biology to ensure its own survival is no small feat,” said Goodrum, also a member of the UA’s BIO5 Institute.”CMV is a master of human cell biology. From transcribing DNA into blueprints for proteins to the manufacturing of those proteins, from cell division to cellular metabolism, there is not a process this virus has not tweaked,” Goodrum also said.That mastery, she explained, is the reason the virus is so elusive to vaccine, and there currently is no way to eradicate it. Goodrum noted that with other herpes viruses, like Epstein-Barr or chicken pox, the infection is obvious. But that is not the case with CMV.”From the perspective of a virus, that is the pinnacle of mastery — to infect without ever making its presence known,” Goodrum said.”To develop more effective antiviral strategies, we must understand the biology of the virus infection and how the virus manages to persist for our lifetimes,” she said. “We are trying to understand how our cellular mechanisms are being used by this virus and discover targets for drugs to control it.”Each human cell contains a thread of DNA that is about 6 feet long, stowed away in its nucleus and tightly packaged by proteins called histones. One such package of genetic material is called a chromosome.”You can imagine histones as a spool, and the thread is DNA that wraps around the spool,” Goodrum said. …

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Honey bee gene targeting offers system to understand food-related behavior

July 25, 2013 — On July 25th JoVE, the Journal of Visualized Experiments will publish a new technique that will help scientists better understand the genes that govern food-related behavior in honey bees. The impact of this study could take scientists one-step closer toward understanding — and perhaps changing — undesirable food-related behavior in humans via gene control.”Our technique has already helped to unravel [the] complex gene networks behind biological processes and behavior, such as gustatory perception,” said Dr. Ying Wang of Arizona State University. She and a team of scientists are behind the experiment, titled RNAi-mediated Double Gene Knockdown and Gustatory Perception Measurement in Honey Bees. “Honey bees are much less complex than mammals and humans, but [we] share many major genes,” said Wang, “therefore, honey bees have become an emerging system for us to understand food related behavior in humans.”In Wang’s previous study, she found that carbohydrate metabolism and insulin pathway genes were involved in honey bee gustatory perception. Her new article introduces two strategies for targeting and simultaneously down-regulating multiple genes in honey bees via RNA interference. This allows for further research in examining the role of insulin metabolism in gustatory perception. The team believes it will be important to understanding how insulin pathways play a role in food-related behavior.Wang’s multiple gene knockdown method is a first in entomology, and it overcomes the many shortfalls associated with typical single-gene targeting methods. A common problem associated with single gene suppression is that it is not sufficient to show the interrelationship of a gene network.In the article published today, Wang’s team has also provided a technique to measure the resulting changes in honey bee behavior, and this has led them to interesting observations. “Gustatory perception is a behavioral predictor for honey bee social behavior,” said Wang. …

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Evolution too slow to keep up with climate change

July 9, 2013 — Many vertebrate species would have to evolve about 10,000 times faster than they have in the past to adapt to the rapid climate change expected in the next 100 years, a study led by a University of Arizona ecologist has found.Scientists analyzed how quickly species adapted to different climates in the past, using data from 540 living species from all major groups of terrestrial vertebrates, including amphibians, reptiles, birds and mammals. They then compared their rates of evolution to rates of climate change projected for the end of this century. This is the first study to compare past rates of adaption to future rates of climate change.The results, published online in the journal Ecology Letters, show that terrestrial vertebrate species appear to evolve too slowly to be able to adapt to the dramatically warmer climate expected by 2100. The researchers suggested that many species may face extinction if they are unable to move or acclimate.”Every species has a climatic niche which is the set of temperature and precipitation conditions in the area where it lives and where it can survive,” explained John J. Wiens, a professor in UA’s department of ecology and evolutionary biology in the College of Science. “For example, some species are found only in tropical areas, some only in cooler temperate areas, some live high in the mountains, and some live in the deserts.”Wiens conducted the research together with Ignacio Quintero, a postgraduate research assistant at Yale University.”We found that on average, species usually adapt to different climatic conditions at a rate of only by about 1 degree Celsius per million years,” Wiens explained. “But if global temperatures are going to rise by about 4 degrees over the next hundred years as predicted by the Intergovernmental Panel of Climate Change, that is where you get a huge difference in rates. What that suggests overall is that simply evolving to match these conditions may not be an option for many species.”For their analysis, Quintero and Wiens studied phylogenies — essentially evolutionary family trees showing how species are related to each other — based on genetic data. These trees reveal how long ago species split from each other. The sampling covered 17 families representing the major living groups of terrestrial vertebrates, including frogs, salamanders, lizards, snakes, crocodilians, birds and mammals.They then combined these evolutionary trees with data on the climatic niche of each species to estimate how quickly climatic niches evolve among species, using climatic data such as annual mean temperature and annual precipitation as well as high and low extremes.”Basically, we figured out how much species changed in their climatic niche on a given branch, and if we know how old a species is, we can estimate how quickly the climatic niche changes over time,” Wiens explained. …

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Clues about autism may come from the gut

July 4, 2013 — Bacterial flora inhabiting the human gut have become one of the hottest topics in biological research. Implicated in a range of important activities including digestion, fine-tuning body weight, regulating immune response, and producing neurotransmitters that affect brain and behavior, these tiny workers form diverse communities. Hundreds of species inhabit the gut, and although most are beneficial, some can be very dangerous.In new research appearing in the journal PLOS ONE, a team led by Rosa Krajmalnik-Brown, a researcher at Arizona State University’s Biodesign Institute, present the first comprehensive bacterial analysis focusing on commensal or beneficial bacteria in children with autism spectrum disorder (ASD).After publishing earlier research exploring crucial links between intestinal microflora and gastric bypass, Krajmlanik-Brown convinced James Adams — director of the ASU Autism/Asperger’s Research Program — that similar high throughput techniques could be used to mine the microbiome of patients with autism. (Previously, Adams had been studying the relationship between the gut microbiome and autism using traditional culturing techniques.)”One of the reasons we started addressing this topic is the fact that autistic children have a lot of GI problems that can last into adulthood,” Krajmalnik-Brown says. “Studies have shown that when we manage these problems, their behavior improves dramatically.”Following up on these tantalizing hints, the group hypothesized the existence of distinctive features in the intestinal microflora found in autistic subjects compared to typical children. The current study confirmed these suspicions, and found that children with autism had significantly fewer types of gut bacteria, probably making them more vulnerable to pathogenic bacteria. Autistic subjects also had significantly lower amounts of three critical bacteria, Prevotella, Coprococcus, and Veillonellaceae.Krajmalnik-Brown, along with the paper’s lead authors Dae-Wook Kang and Jin Gyoon Park, suggest that knowledge gleaned through such research may ultimately be used both as a quantitative e diagnostic tool to pinpoint autism and as a guide to developing effective treatments for ASD-associated GI problems. The work also offers hope for new prevention and treatment methods for ASD itself, which has been on a mysterious and rapid ascent around the world.A disquieting puzzleAutism is defined as a spectrum disorder, due to the broad range of symptoms involved and the influence of both genetic and environmental factors, features often confounding efforts at accurate diagnosis. The diseases’ prevalence in children exceeds juvenile diabetes, childhood cancer and pediatric AIDS combined.Controversy surrounds the apparent explosive rise in autism cases. Heightened awareness of autism spectrum disorders and more diligent efforts at diagnosis must account for some of the increase, yet many researchers believe a genuine epidemic is occurring. …

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