Low testosterone levels may herald the subsequent development of rheumatoid arthritis in men, suggests research published online in the Annals of the Rheumatic Diseases. Sex hormones are thought to play a part in the development of rheumatoid arthritis, and both men and women with the condition tend to have lower levels of testosterone in their blood than healthy people. But it is not clear whether this is a contributory factor or a consequence of the disease. The researchers based their findings on participants of the Swedish Malmo Preventive Medicine Program (MPMP), ...

In an advance for HIV vaccine research, scientists have for the first time determined how both the virus and a resulting strong antibody response co-evolved in one HIV-infected individual. The findings could help researchers identify which proteins to use in investigational vaccines to induce antibodies capable of preventing infection from an array of HIV strains. Previously, a study of antibody genetics enabled scientists to deduce the step-by-step evolution of certain broadly neutralizing antibodies—those that can prevent infection by the majority of HIV strains found ...

The Gilbert Island reefs in the Central Pacific were once home to two species of sharks not previously reported in historic records or contemporary studies. The species were discovered in a new analysis of weapons made from shark teeth and used by 19th century islanders, reported in a study published April 3 in the open access journal PLOS ONE by Joshua Drew from Columbia University and colleagues from the Field Museum of Natural History. Sharks were culturally important to the Gilbertese Islanders; historic records indicate a complex ritual system surrounding shark fishing ...

WHAT: National Institutes of Health (NIH) researchers have developed a model of infection in rhesus macaques that will help scientists around the world better understand how an emerging coronavirus, first identified in September 2012, affects people. The virus has so far infected at least 17 people in the Middle East and Europe, killing 11 of them. The NIH team established the nonhuman primate model in December 2012 and is using it to study how the virus causes disease and to evaluate potential vaccines and antiviral treatments. The model shows that clinical signs ...

By stimulating one part of the brain with laser light, researchers at the National Institutes of Health (NIH) and the Ernest Gallo Clinic and Research Center at UC San Francisco (UCSF) have shown that they can wipe away addictive behavior in rats – or conversely turn non-addicted rats into compulsive cocaine seekers. "When we turn on a laser light in the prelimbic region of the prefrontal cortex, the compulsive cocaine seeking is gone," said Antonello Bonci, MD, scientific director of the intramural research program at the NIH's National Institute of Drug Abuse (NIDA), ...

SAN FRANCISCO -- About 4 to 5 million years ago, the Earth was warmer than today. Now that greenhouse gas pollution has the planet's temperature rising again, researchers want to know more about why this early Pliocene period was so warm, with the hopes of improving future climate predictions. A new study in the journal Nature concludes that it is difficult to model the exact conditions behind the pattern of warming in the early Pliocene. None of the proposed mechanisms—from high carbon dioxide levels to changes in global ocean circulation patterns—can explain why the ...

A huge pool of warm water that stretched out from Indonesia over to Africa and South America four million years ago suggests climate models might be too conservative in forecasting tropical changes. Present in the Pliocene era, this giant mass of water would have dramatically altered rainfall in the tropics, possibly even removing the monsoon. Its decay and the consequential drying of East Africa may have been a factor in Hominid evolution. Published in Nature today, the missing data for this phenomenon could have significant implications when predicting the future ...

PITTSBURGH, April 3, 2013 – A reformulated version of an anti-HIV gel developed for vaginal use was found safe and acceptable by HIV-negative men and women who used it rectally, according to a Phase I clinical trial published today in PLOS ONE. The study, led by researchers with the U.S. National Institutes of Health (NIH)-funded Microbicide Trials Network (MTN), tested a reduced glycerin formulation of tenofovir gel, and has spurred the development of an expanded safety study of the gel, expected to launch later this year. Rectal microbicides, gel-based antiretroviral ...

More useful projections of sea level are possible despite substantial uncertainty about the future behavior of massive ice sheets, according to Princeton University researchers. In two recent papers in the journals Nature Climate Change and the Proceedings of the National Academy of Sciences (PNAS), the researchers present a probabilistic assessment of the Antarctic contribution to 21st-century sea-level change. Their methodology folds observed changes and models of different complexity into unified projections that can be updated with new information. This approach ...

ATLANTA – Humans' closest animal relatives, chimpanzees, have the ability to "think about thinking" – what is called "metacognition," according to new research by scientists at Georgia State University and the University at Buffalo. Michael J. Beran and Bonnie M. Perdue of the Georgia State Language Research Center (LRC) and J. David Smith of the University at Buffalo conducted the research, published in the journal Psychological Science of the Association for Psychological Science. "The demonstration of metacognition in nonhuman primates has important implications ...

VIDEO: This animation shows the seasonal change in the extent of the Arctic sea ice between March 1, 2012 and February 28, 2013. The annual cycle starts with the maximum extent... Click here for more information. Last September, at the end of the northern hemisphere summer, the Arctic Ocean's icy cover shrank to its lowest extent on record, continuing a long-term trend and diminishing to about half the size of the average summertime extent from 1979 to 2000. During the cold ...

ANN ARBOR—The rare Green Pea galaxies discovered by the general public in 2007 could help confirm astronomers' understanding of reionization, a pivotal stage in the evolution of the early universe, say University of Michigan researchers. Reionization occurred a few hundred million years after the Big Bang as the first stars were turning on and forming the first galaxies. During this period, the space between the galaxies changed from an opaque, neutral fog to a transparent charged plasma, as it is today. Plasma is gas that's electrically charged. As for how this happened, ...

Jumping silicon atoms are the stars of an atomic scale ballet featured in a new Nature Communications study from the Department of Energy's Oak Ridge National Laboratory. The ORNL research team documented the atoms' unique behavior by first trapping groups of silicon atoms, known as clusters, in a single-atom-thick sheet of carbon called graphene. The silicon clusters, composed of six atoms, were pinned in place by pores in the graphene sheet, allowing the team to directly image the material with a scanning transmission electron microscope. The "dancing" movement ...

The mountain ranges of the North American Cordillera are made up of dozens of distinct crustal blocks. A new study clarifies their mode of origin and identifies a previously unknown oceanic plate that contributed to their assembly. The extensive area of elevated topography that dominates the Western reaches of North America is exceptionally broad, encompassing the coastal ranges, the Rocky Mountains and the high plateaus in between. In fact, this mountain belt consists of dozens of crustal blocks of varying age and origin, which have been welded onto the American continent ...

The initial clinical trial of a novel approach to treating amyotrophic lateral sclerosis (ALS) – blocking production of a mutant protein that causes an inherited form of the progressive neurodegenerative disease – may be a first step towards a new era in the treatment of such disorders. Investigators from Massachusetts General Hospital (MGH) and Washington University School of Medicine report that infusion of an antisense oligonucleotide against SOD1, the first gene to be associated with familial ALS, had no serious adverse effects and the drug was successfully distributed ...

New research out of St. Michael's Hospital has found that multiple factors independently predict what makes youth more likely to make repeat suicide-related behaviour. The study, led by Dr. Anne Rhodes, a research scientist at the hospital's Suicide Studies Research Unit, looked at whether factors such as permanent removal from the parental home by the courts due to maltreatment, neighbourhood size or income, gender, severity of first visit to an emergency department, age or having a mental disorder made youth significantly more likely to repeat suicide-related behavior. "We ...

Washington–A new study from The Pew Charitable Trusts, "Making Hard Choices: Navigating the Economic Shock of Unemployment," examines how American families cope with unexpected financial setbacks and how those periods of economic uncertainty draw down financial resources. The report studies families across race and income levels, revealing different experiences resulting from unemployment and the difficult choices many of them face. Building upon Pew's prior research, this report underscores the significance of financial resources other than income, particularly savings ...

Researchers at Moffitt Cancer Center have determined that the overexpression of microRNA-155 (miR-155), a short, single strand of ribonucleic acid encoded by the miR-155 host gene, promotes the growth of blood vessels in tumors, tumor inflammation, and metastasis. As a therapeutic target, miR-155 could potentially provide a new avenue of treatment when targeted with drugs to suppress its activity. The study was published in an online issue of Oncogene in January. MiR-155, which plays an important role in various physiological and pathological processes, is considered ...

JUPITER, FL, April 3, 2013 – Human diseases caused by misfolded proteins known as prions are some of most rare yet terrifying on the planet—incurable with disturbing symptoms that include dementia, personality shifts, hallucinations and coordination problems. The most well-known of these is Creutzfeldt-Jakob disease, which can be described as the naturally occurring human equivalent of mad cow disease. Now, scientists from the Florida campus of The Scripps Research Institute (TSRI) have for the first time identified a pair of drugs already approved for human use that ...

PubMed Central may draw readership away from biomedical journal sites, with this effect increasing over time. This finding—that PubMed Central directly competes with biomedical publishers—was published online in The FASEB Journal. In the study, Phillip M. Davis shows that as articles are deposited in PubMed Central, they draw readership away from the scientific journal even when journals themselves are providing free access to the articles. Over time, this may weaken the ability of journals to build communities of interest around research papers, impede the communication ...

University of Notre Dame researchers have successfully created three-dimensional anatomical models from CT scans using 3-D printing technology, a process that holds promise for medical professionals and their patients. A paper by the researchers, "3D Printing of Preclinical X-ray Computed Tomographic Data Sets," was published in the Journal of Visualized Experiments this week. The strategy was initiated last spring by then-freshman Evan Doney, a Glynn Family Honors student in the laboratory of W. Matthew Leevy, research assistant professor at the Notre Dame Integrated ...

Coral Gables, Fla. – April 2, 2013 -- New research from the University of Miami School of Business Administration offers marketers a strategy for how best to structure free giveaways with products in order to maximize sales. The study, just published in the Journal of Marketing, shows that when a product that triggers more emotion (called affect), such as makeup, is offered with a free gift, shoppers are more likely to buy that product if the type of gift is unknown than if the type of gift is revealed. So much so, that in this case, it can up to double the purchase ...

Bottom-up synthesis of nanowires through metal-catalyzed vapor phase epitaxy is a very attractive process to generate high-quality nanowires thus providing an additional degree of freedom in design of innovative devices that extend beyond what is achievable with the current technologies. In this nano-fabrication process, nanowires grow through the condensation of atoms released from a molecular vapor (called precursors) at the surface of metallic nano-droplets. Gold is broadly used to form these nano-droplets. This self-assembly of nanowires takes place spontaneously ...

Could drug addiction treatment of the future be as simple as an on/off switch in the brain? A study in rats has found that stimulating a key part of the brain reduces compulsive cocaine-seeking and suggests the possibility of changing addictive behavior generally. The study, published in Nature, was conducted by scientists at the Intramural Research Program of the National Institute on Drug Abuse (NIDA), part of the National Institutes of Health, and the University of California, San Francisco. "This exciting study offers a new direction of research for the treatment ...

Scientists have decoded the genome of the western painted turtle, one of the most abundant turtles on Earth, finding clues to their longevity and ability to survive without oxygen during long winters spent hibernating in ice-covered ponds. Understanding the natural mechanisms turtles use to protect the heart and brain from oxygen deprivation may one day improve treatments for heart attacks or strokes, the researchers say. Both can lead to severe disability or death within minutes in patients deprived of oxygen. The research team includes scientists at Washington University ...