STANFORD, Calif. — Stanford University School of Medicine scientists have used bioengineered mice with livers composed largely of human cells to characterize a drug about to enter early-stage clinical development for combating hepatitis C. Tests using the new mouse model accurately predicted significant aspects of the drug's behavior in humans — including its interaction with another drug and the profile of its major breakdown products in the body (called metabolites) — far more accurately than would have been achieved using current methods. The study will be published ...

PITTSBURGH, Oct. 31, 2012 – Reforming Medicare payments based on large geographic regions may be too bluntly targeted to promote the best use of health care resources, a new analysis from the University of Pittsburgh Graduate School of Public Health suggests. The analysis will be published in the Nov. 1 issue of the New England Journal of Medicine. "Much policy attention has been drawn to the large geographic variation in health care spending across regions, and for good reason – because regional variation points to inefficient use of resources," said lead author Yuting ...

Berkeley — The more time it takes for an earthquake fault to heal, the faster the shake it will produce when it finally ruptures, according to a new study by engineers at the University of California, Berkeley, who conducted their work using a tabletop model of a quake fault. "The high frequency waves of an earthquake — the kind that produces the rapid jolts — are not well understood because they are more difficult to measure and more difficult to model," said study lead author Gregory McLaskey, a former UC Berkeley Ph.D. student in civil and environmental engineering. ...

The well-established elevated risk of melanoma among people with red hair and fair skin may be caused by more than just a lack of natural protection against ultraviolet (UV) radiation. In an article receiving Advance Online Publication in Nature, Massachusetts General Hospital (MGH) Cutaneous Biology Research Center (CBRC)and Cancer Center researchers report finding that the type of skin pigment predominantly found in red-haired, fair-skinned individuals may itself contribute to the development of melanoma. "We've known for a long time that people with red hair and ...

This month's special issue of Physics World is devoted to animal physics, and includes science writer Stephen Ornes explanation of how pond skaters effortlessly skip across water leaving nothing but a small ripple in their wake. As Ornes writes, our current understanding of the mechanisms adopted by the pond skater is down to the efforts of David Hu, who as a mathematics graduate from the Massachusetts Institute of Technology spent four years studying their behaviour. Hu, along with his PhD supervisor John Bush, found that pond skaters use the middle of their three ...

A new study suggests that increasing the amount of sleep that adults get could lead to reduced food intake, but the hormonal process differs between men and women. "Restricting sleep in healthy, normal weight participants has limited effects on metabolic risk factors and may affect food intake regulating hormones differently in men and women," said Marie-Pierre St-Onge, PhD, FAHA, the study's principal investigator. "We were surprised by the lack of a significant effect of sleep on glucose and insulin, leptin, and sex differences in the hunger-stimulating hormone ghrelin ...

Completing the second phase of the 1000 Genomes Project, a multinational team of scientists reports that they have sampled a total of 1092 individuals from 14 different populations and sequenced their full genomes. The researchers described the feat as a collegial effort to equip biologists and physicians with information that can be used to understand the normal range of human genetic variants so that a patient's disease genome can be interpreted in a broader context. A report on the research, published online in Nature on Nov. 1 represents the culmination of five years ...

HOUSTON -- (Nov. 1, 2012) – First, there was the single human reference genome completed in 2003. Then there was the HapMap project to identify the common genetic variants occurring in human beings with the first map published in 2005. Now an international consortium has released the first phase of the 1,000 Genomes Project that profiles the rare and common genetic variations in 1,092 people drawn from 14 human populations from Europe, Africa, East Asia and the Americas. The next phase of the project will include as many as 3,000 individuals, said Dr. Fuli Yu (www.bcm.edu/genetics/index.cfm?pmid=23673 ), ...

Crohn's disease (CD) and ulcerative colitis (UC) – inflammatory diseases of the gastrointestinal tract – have puzzled the scientific community for decades. Ten years ago, researchers recognized that both genes and the environment contributed to these diseases but knew little about precisely how and why illness occurred. To begin to narrow in on the key pathways involved, they would need thousands of patients' samples, millions of data points, and the commitment of physicians and scientists at dozens of institutions. Today, researchers from across the CD and UC communities ...

Fear of math can activate regions of the brain linked with the experience of physical pain and visceral threat detection, according to research published Oct 31 by Ian Lyons and colleagues at the University of Chicago in the open access journal PLOS ONE. The researchers found that in individuals who experience high levels of anxiety when facing math tasks, the anticipation of math increases activity in regions of the brain associated with the physical sensation of pain. The higher an individual's math anxiety, the more such neural activity was increased. According ...

Children as young as five are generous when others are aware of their actions, but antisocial when sharing with a recipient who can't see them, according to research published Oct. 31 in the open access journal PLOS ONE by Kristin Lyn Leimgruber and colleagues from Yale University. Adults are more likely to behave in ways that enhance their reputation when they are being watched or their actions are likely to be made public than when they are anonymous, but this study examines the origins of such behavior in young children for the first time. For their study, the researchers ...

When there is little water available for plants to grow, their roots form alliances with soil microbes that can promote plant growth even under water-limiting conditions, according to research published Oct. 31 by Daniele Daffonchio and colleagues from the University of Milan, Italy in the open access journal PLOS ONE. Symbiotic relationships between plants and soil microbial communities are critical to the health of plants. Though the effects of drought on plants are well-known, little is known about how lack of water affects the bacteria around plant roots. In this ...

A large proportion of aspen in the western U.S. sport an extra set of chromosomes in their cells, a phenomenon termed triploidy, according to new research published Oct. 31 in the open access journal PLoS ONE by Karen Mock from Utah State University and colleagues at several other institutions. In some areas of southern Utah and Colorado, over 60% of aspen trees are triploid. Though triploid trees are not uncommon, this genetic anomaly can cause altered physical traits including sterility or reduced fertility. Although a triploid aspen clone may reproduce with root ...

In one of the largest studies of its kind, researchers have identified 71 genetic regions newly associated with inflammatory bowel disease (IBD), increasing the total number discovered to date to 163. This new information reveals that there is a vast amount of genetic overlap between Crohn's disease and Ulcerative colitis (the two most common subtypes of IBD), suggesting that they share common biological pathways. In addition, analyzing these regions reveals that IBD may result from the body's immune response over-reacting, the result of a long-term evolutionary balancing ...

Australia's giant eucalyptus trees are the tallest flowering plants on earth, yet their unique relationship with fire makes them a huge puzzle for ecologists. Now the first global assessment of these giants, published in New Phytologist, seeks to end a century of debate over the species' classification, a debate which may determine their future. Gigantic trees are as rare as they are awe inspiring. Of the 100,000 global tree species only 50, less than 0.005%, reach over 70 meters in height. While many of these giants live in Pacific North America, Borneo and similar habitats, ...

A drug which 'reboots' a person's immune system has been shown to be an effective treatment for multiple sclerosis (MS) patients who have already failed to respond to the first drug with which they were treated (a 'first-line' therapy), as well as affected individuals who were previously untreated. The results of these two phase III clinical trials were published today in the journal The Lancet. The new studies, sponsored by Genzyme (a Sanofi company) and Bayer Schering Pharma, showed that alemtuzumab significantly reduces the number of attacks (or relapses) experienced ...

Halving the amount of nitrogen fertiliser used in certain areas of China would substantially decrease greenhouse gas emissions without affecting crop productivity and the area's natural carbon sink. This is according to a new study, published today, 1 November, in IOP Publishing's Environmental Research Letters, which showed that a 60 per cent reduction in fertiliser use would significantly reduce emissions from areas that are, anyway, "over-fertilised", such as the North China Plain and middle and lower reaches of the Yangtze River Basin. China is currently tasked ...

A landmark project that has sequenced 1,092 human genomes from individuals around the world will help researchers to interpret the genetic changes in people with disease. The first study to break the '1000 genomes barrier' will enable scientists to begin to examine genetic variations at the scale of the populations of individual countries, as well as guiding them in their search for the rare genetic variations related to many diseases. The vast majority of genetic variation is shared with populations around the world but it is thought that a lot of the contribution ...

When people worry about math, the brain feels the pain Mathematics anxiety can prompt a response in the brain similar to when a person experiences physical pain, according to new research at the University of Chicago. Using brain scans, scholars determined that the brain areas active when highly math-anxious people prepare to do math overlap with the same brain areas that register the threat of bodily harm—and in some cases, physical pain. "For someone who has math anxiety, the anticipation of doing math prompts a similar brain reaction as when they experience pain—say, ...

Patients newly diagnosed with type 2 diabetes feel "left in the dark" and unsure what they can and can't eat whilst sometimes waiting months to receive diabetes education, according to a new study published online today in the journal Primary Health Care Research & Development (1). The research carried out by Dr Michelle McKinley and colleagues at Queen's University Belfast, explored the views of people recently diagnosed with diabetes and discovered that whilst waiting for a referral to a diabetes education programme, they received little or no information about what to ...

Short-term alcohol intake can increase the activity of functional connections across the human brain when it is at rest, according to research published Oct 31 in the open access journal PLOS ONE by Panagiotis Bamidis and colleagues from the Aristotle University of Thessaloniki, Greece. Previous studies have shown that alcohol intake increases transmission of signals by the neurotransmitter GABA, present in 40% of the connections between nerve cells in the brain. Here, the researchers monitored resting brain activity in healthy social drinkers who had consumed one drink, ...

New Haven, Conn. — A Yale-led scientific team has produced the most comprehensive family tree for birds to date, connecting all living bird species — nearly 10,000 in total — and revealing surprising new details about their evolutionary history and its geographic context. Analysis of the family tree shows when and where birds diversified — and that birds' diversification rate has increased over the last 50 million years, challenging the conventional wisdom of biodiversity experts. "It's the first time that we have — for such a large group of species and with such a ...

The world's first family tree linking all living bids and revealing when and where they evolved and diversified since dinosaurs walked the earth has been created by scientists from the University of Sheffield. Experts used the family tree to map out where the almost 10,000 species of birds live to show where the most diversification has taken place in the world. Researchers, from the University of Sheffield, Yale University, University of Tasmania and Simon Fraser University, say the creation of new species has speeded-up over the last 50 million years. Surprisingly, ...

Uncontrolled high blood pressure damages the brain's structure and function as early as young middle-age, and even the brains of middle-aged people who clinically would not be considered to have hypertension have evidence of silent structural brain damage, a study led by researchers at UC Davis has found. The investigation found accelerated brain aging among hypertensive and prehypertensive individuals in their 40s, including damage to the structural integrity of the brain's white matter and the volume of its gray matter, suggesting that vascular brain injury "develops ...

Like a movie star constantly retouching her makeup, the protoplanet Vesta is continually stirring its outermost layer and presenting a young face. New data from NASA's Dawn mission show that a common form of weathering that affects many airless bodies like Vesta in the inner solar system, including the moon, surprisingly doesn't age the protoplanet's outermost layer. The data also indicate that carbon-rich asteroids have been splattering dark material on Vesta's surface over a long span of the body's history. The findings are described in two papers published ...