SANTA CRUZ, CA--A 30,000-year-old finger bone found in a cave in southern Siberia came from a young girl who was neither an early modern human nor a Neanderthal, but belonged to a previously unknown group of human relatives who may have lived throughout much of Asia during the late Pleistocene epoch. Although the fossil evidence consists of just a bone fragment and one tooth, DNA extracted from the bone has yielded a draft genome sequence, enabling scientists to reach some startling conclusions about this extinct branch of the human family tree, called "Denisovans" after ...

EDITOR'S PICK: What sex are you? Sex in mammals is genetically determined. In humans, females have two X chromosomes, while males have one X and one Y chromosome. However, some individuals are born with male genitalia despite having two X chromosomes, a condition known as XX male sex reversal. A team of researchers, led by Paul Thomas, University of Adelaide, Australia, has now determined that overexpression of the Sox3 gene in mice causes frequent XX male sex reversal. The clinical relevance of this was highlighted by the discovery of genomic rearrangements in the regulatory ...

BOSTON (December 22, 2010) -- Is quality in the eye of the beholder? Researchers at Harvard Medical School and Massachusetts General Hospital have found wide disparities among four common measures of hospital-wide mortality rates, with competing methods yielding both higher- and lower-than-expected rates for the same Massachusetts hospitals during the same year. The findings, published Dec. 23 in a special article in the New England Journal of Medicine, stoke a simmering debate over the value of hospital-wide mortality rates as a yardstick for health care quality. ...

BOSTON, Mass. (December 22, 2010) — The sequencing of the nuclear genome from an ancient finger bone found in a Siberian cave shows that the cave dwellers were neither Neandertals nor modern humans. An international team of researchers led by Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology in Leipzig (Germany) has sequenced the nuclear genome from a finger bone of an extinct hominin that is at least 30,000 years old and was excavated by archaeologists from the Russian Academy of Sciences in Denisova Cave in southern Siberia, Russia, in 2008. A ...

For most of us, the "placebo effect" is synonymous with the power of positive thinking; it works because you believe you're taking a real drug. But a new study rattles this assumption. Researchers at Harvard Medical School's Osher Research Center and Beth Israel Deaconess Medical Center (BIDMC) have found that placebos work even when administered without the seemingly requisite deception. The study published on December 22 in PLoS ONE. Placebos—or dummy pills—are typically used in clinical trials as controls for potential new medications. Even though they contain ...

Specially designed probiotics can modulate the physiology of host fat cells say scientists writing in Microbiology. The findings could lead to specialised probiotics that have a role in the prevention or treatment of conditions such as obesity. Scientists from the Alimentary Pharmabiotic Centre (APC), Cork, University College Cork and Teagasc, in Ireland engineered a strain of Lactobacillus to produce a version of a molecule called conjugated linoleic acid (CLA). When this engineered bacterial strain was fed to mice, the researchers found that the composition of the mice's ...

Scientists today published catalogs of the fruit fly and roundworm's functional genomic elements: DNA sequences in the genome that carry the instructions and determine which genes are turned on and off at various times in different cells. Initially sequenced as part of the Human Genome Project, the genomes of the fruit fly, Drosophila melanogaster, and the roundworm, Caenorhabditis elegans, are powerful models for understanding human biology and disease, as many functional genomic elements have been conserved across the vast evolutionary distances separating each organism. ...

Penn State researchers have found that native pollinators, like wild bees and wasps, are infected by the same viral diseases as honey bees and that these viruses are transmitted via pollen. Their research published on December 22nd in PLoS ONE, an online open-access journal for the communication of all peer-reviewed scientific and medical research. This multi-institutional study provides new insights into viral infections in native pollinators, suggesting that viral diseases may be key factors impacting pollinator populations. According to Diana Cox-Foster, co-author ...

In the past decade researchers have made astonishing progress in the rapid and accurate sequencing of genomes from all realms of life. Yet the listing of chemical base pairs has gotten far ahead of understanding how the information they contain becomes functional. Even the best-understood genomes conceal mysteries. Genetic information carried by DNA and RNA operates together with the patterns and physical organization of chromosomes to produce a working organism. Major advances in understanding these complex relationships are published this week by the "model organism ...

DALLAS – Dec. 22, 2010 – UT Southwestern Medical Center researchers have pinpointed a tiny site in the brain where the hormone leptin may help trigger the onset of puberty. The findings in mice indicate that a site within the hypothalamus called the ventral premammillary nucleus, or PMV, is the target where the hormone leptin effectively kick starts puberty in females. Researchers have known that puberty starts when individuals have enough energy stores or fat to meet the demands of reproduction, and that leptin – a hormone produced by fat cells – acts in the brain ...

Australian scientists have discovered that changes to a gene involved in brain development can lead to testis formation and male genitalia in an otherwise female embryo. Lead Melbourne researcher Professor Andrew Sinclair, of the Murdoch Childrens Research Institute and the University of Melbourne, said the breakthrough would improve diagnosis and clinical management of patients with disorders of sex development (DSD). These conditions occur when the testes or ovaries do not develop properly in the embryo, causing genital abnormalities in one in 4500 babies. The gene, ...

University of Adelaide researchers are a step closer to unraveling the mysteries of human sexual development, following genetic studies that show male mice can be created without a Y chromosome – through the activation of an ancient brain gene. Males usually have one Y chromosome and one X chromosome, while females have two X chromosomes. A single gene on the Y, called SRY, triggers testes development in the early embryo, and once these begin to form, the rest of the embryo also becomes male. However, Adelaide researchers have discovered a way of creating a male mouse ...

Shouldering family demands and worries seems to increase the risk of angina, the precursor to coronary artery disease, reveals research published online in the Journal of Epidemiology and Community Health. Previous research has indicated that rewarding personal relationships are a boost for heart health, so the authors wanted to know if the reverse might also be true. They tracked the heart health of more than 4,500 randomly selected men and women in their 40s and 50s for six years. None had any heart problems at the start of the study in 1999. In 2006 all participants ...

Complementary medicines (CAM) can be dangerous for children and can even prove fatal, if substituted for conventional medicine, indicates an audit of kids' CAM treatment published online in the Archives of Disease in Childhood. But parents often misguidedly think CAM treatments are better for their children because they are "natural" and therefore less likely to have harmful side effects, say the authors. They base their findings on monthly reporting of adverse events associated with CAM to the Australian Paediatric Surveillance Unit between 2001 and 2003. During ...

Teen girls living in the most deprived areas are five times as likely to be assaulted as their affluent male and female peers, reveals research published online in Emergency Medicine Journal. Young men are twice as likely to be a victim of assault as young women, but the link between deprivation and assault is far stronger for their female peers, the study shows. Violence is the third leading cause of death among 15 to 19 year olds and the 14th leading cause of death among 10 to 14 year olds worldwide. In 2007, around 66,000 children and teens in England and Wales were ...

Running and swimming records are broken again and again at almost every international athletics event. But, can human performance continue to improve indefinitely? Will runners continue to accelerate off the starting blocks and reach the finish line in faster and faster times? Will swimmers always be able to dive into the record books with a quicker kick? Writing in the International Journal of Applied Management Science, researchers from South Korea have analyzed data from sports events over the last one hundred years and have calculated that we could reach the upper ...

Searching the web usually involves typing keywords or a phrase into a search engine and clicking the "search now" button. It's very effective and several large companies have become prominent in the field by providing users with searchable access to millions, if not billions of web pages in this way. However, according to researchers at Hewlett Packard in Palo Alto, California and Chinese technology company, Innovation Works, general search engines, while very effective at tracking down information, are nevertheless unstructured, which limits the user's ability to further ...

Trinitramid – that's the name of the new molecule that may be a component in future rocket fuel. This fuel could be 20-30 percent more efficient in comparison with the best rocket fuels we have today. The discovery was made at the Royal Institute of Technology (KTH) in Sweden. "A rule of thumb is that for every ten-percent increase in efficiency for rocket fuel, the payload of the rocket can double. What's more, the molecule consists only of nitrogen and oxygen, which would make the rocket fuel environmentally friendly. This is more than can be said of today's solid ...

A major new fossil site in south-west China has filled in a sizeable gap in our understanding of how life on this planet recovered from the greatest mass extinction of all time, according to a paper co-authored by Professor Mike Benton, in the School of Earth Sciences, and published this week in the Proceedings of the Royal Society B. The work is led by scientists from the Chengdu Geological Center in China. Some 250 million years ago, at the end of the time known as the Permian, life was all but wiped out during a sustained period of massive volcanic eruption and devastating ...

Albert Einstein once said that science without religion is lame, and religion without science is blind. Now a Tel Aviv University researcher is one of the first to explore the link between these two realms in the Muslim world. Clinical psychologist Dr. Hisham Abu-Raiya of Tel Aviv University's Bob Shapell School of Social Work is investigating how various Islamic beliefs and practices impact the psychological well-being of its adherents. Among American Muslims, he's attempting to scientifically quantify how the after-effects of the 9/11 attacks have affected mental ...

While there are still couples who wait for a deep level of commitment before having sex, today it's far more common for two people to explore their sexual compatibility before making long-term plans together. So does either method lead to better marriages? A new study in the American Psychological Association's Journal of Family Psychology sides with a delayed approach. The study involves 2,035 married individuals who participated in a popular online marital assessment called "RELATE." From the assessment's database, researchers selected a sample designed to match ...

NASA and the National Science Foundation launched a scientific balloon on Monday, December 20, Eastern Standard time, to study the effects of cosmic rays on Earth. It was the first of five scientific balloons scheduled to launch from Antarctica in December. The Cosmic Ray Energetics And Mass (CREAM VI) experiment was designed and built at the University of Maryland. CREAM is investigating high-energy cosmic-ray particles that originated from distant supernovae explosions in the Milky Way and reached Earth. Currently, CREAM VI is floating 126,000 ft above Antarctica with ...

A team at the Institut de recherches cliniques de Montréal (IRCM) led by Dr. Tarik Möröy, President and Scientific Director of the institute and Director of the Hematopoiesis and Cancer research unit, will be publishing an important breakthrough in tomorrow's issue of Immunity, a scientific journal from the Cell Press group. The researchers identified a new regulator playing a critical role in the development B cells, which produce antibodies. Antibodies circulate through the blood and protect against infectious diseases originating from bacteria or viruses. A lack of ...

PITTSBURGH—An international team of researchers led by Carnegie Mellon University's Manojkumar Puthenveedu has discovered the mechanism by which signaling receptors recycle, a critical piece in understanding signaling receptor function. Writing in the journal Cell, the team for the first time describes how a signaling receptor travels back to the cell membrane after it has been activated and internalized. Signaling receptors live on the cell membrane waiting to be matched with their associated protein ligand. When they meet, the two join together like a lock and key, ...

TORONTO, December 22, 2010 − Research from York University is revealing which regions in the brain "fire up" when we suppress an automatic behaviour such as the urge to look at other people as we enter an elevator. A York study, published recently in the journal Frontiers in Human Neuroscience, used fMRI (functional Magnetic Resonance Imaging) to track brain activity when study participants looked at an image of a facial expression with a word superimposed on it. Study participants processed the words faster than the facial expressions. However, when the word did ...