The steroid hormone testosterone regulates the expression of reproductive behaviors and sexual traits of many animal species. While high levels of testosterone are required for reproductive activities or for the expression of sexual traits, these are often costly, and can lead, for instance, to increased parasite infection. Such costs would also ensure honesty in sexual signals or behavior used by animals for assessing the healthiness of a potential mate.

The mechanisms linking elevated

Johns Hopkins researchers have discovered that a single protein regulates secretion levels in the fruit fly’s salivary gland and its skin-like outer layer.

Described in the May 15 issue of Development, the finding improves understanding of how cells become specialized for secretion, which is a critical ability of certain glands and cell types in organisms from insects to humans.

The researchers discovered that a protein called CrebA single-handedly controls the entire

Study focuses on hepatoma

Primary liver cancer is much more likely to take root when a naturally occurring enzyme is in short supply, a team of researchers has found at Mount Sinai Hospital’s Samuel Lunenfeld Research Institute.

Using a knockout mouse model, the team has found that the likelihood of hepatoma, or primary liver cancer, increases substantially when half the normal amount of an enzyme called Plk4 is present. Furthermore, 60 per cent of patients with h

When a pharmaceutical company puts drug samples into the hands of residents as a form of marketing, how does it influence their prescribing behavior? To what extent are treatment decisions based on which samples are available and further, what are the implications for patient care as well as resident education? While this is a frequently debated issue, there has been little objective data describing how drug samples affect resident physicians. In a study published in the August issue of The America

If men thought they were frittering away money wining and dining a girl to win her hand, they should think again. Dr Peter Sozou and Professor Robert Seymour from University College London (UCL) have developed a mathematical model that shows how expensive but worthless gifts may help facilitate courtship.

Reporting in the journal Proceedings of the Royal Society of London B they analysed the function of a courtship gift and what the characteristics of a ‘good’ gift are.

Th

How alike are you and your husband or wife — or, you and your best friend? Probably more alike than you realize. A study of twins shows that people’s spouses and best friends are much more similar to them than was previously recognized — about as close as brothers and sisters. The research also suggested that the preference for partners who are similar to us is partly due to our genes.

The research was conducted by J. Philippe Rushton and Trudy Ann Bons of the University

Happy, sad, angry, scared: Some of us are good at hiding these everyday emotions, while others are unable to disguise them. Whether subtle or intense, facial expressions are the key to how we identify human emotion.

Most studies of how we recognize facial expressions have used static models of intense expressions. But new research indicates that facial motion—seeing the range of movement in the arching of an eyebrow or the curve of a smile—is in fact an extremely important part of w

Study sets foundation for new generation of vaccines for HIV, influenza

Scientists have taken a major step toward the goal of altering viruses, bacteria and tumor cells so that they demand attention from immune cells designed to destroy them. According to research published today in the journal Immunity, researchers at the University of Rochester Medical Center have determined for the first time a single biochemical feature of disease-causing molecules (pathogens) that, if chang

What will retirement look like for you? Will you buy that 40-foot sailboat and sail between your summer home in Maine and your winter home in the Caribbean? Or will you plan for three daughters’ weddings, older parents, and other unexpected but unavoidable costs? One scenario pits you as being solidly independent; the other looks pretty interdependent. How consumers make such choices and set goals is the focus of an article in the September 2005 issue of the Journal of Consumer Research.

Scientists at University College London (UCL) have developed a method of tracking someone’s stream of consciousness based on their brain activity alone. In a study published in the latest issue of Current Biology, the UCL team found that brain activity measured in volunteers who were viewing a visual illusion could be used to accurately track their subjective experience while it underwent many spontaneous changes

In the study, funded by the Wellcome Trust, John-Dylan Haynes and Gerai

Blinking temporarily switches off parts of your brain, according to a study published in the latest issue of Current Biology. The University College London (UCL) team found that the brain actively shuts down parts of the visual system each time you blink, even if light is still entering the eyes. Their findings could explain why you don’t notice your own blinks.

Scientists from the UCL Institute of Neurology designed a special device to study the effects of blinking on the brain.

A testosterone patch may produce modest increases in sexual desire and frequency of satisfying sexual experiences in women who develop distressful, low sexual desire following hysterectomy and removal of the fallopian tubes and ovaries, according to a study in the July 25 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.

Diminished sexual desire has been reported by 30 to 50 percent of women who undergo surgical menopause (menopause induced by the surgi

A paper in this month’s PLoS Medicine concludes that socioeconomic position in adulthood can significantly affect later health. Nancy Krieger and colleagues from Harvard School of Public Health studied 308 pairs of adult female twins from San Francisco who had been raised together until at least age 14. They found that identical twins who had differing socioeconomic position in adulthood differed in their later health.

In identical twins who differed in social class in adulthood,

Two recent studies suggest that multiple rare mutations within a single gene may increase risk for autism, according to investigators with the Vanderbilt Center for Molecular Neuroscience and the Vanderbilt Kennedy Center for Research on Human Development

While debate still rages over the ’cause’ of autism, mounting evidence suggests that genetic factors play a major role in the disease. Two recent studies led by James Sutcliffe, Ph.D., and Randy Blakely, Ph.D., inves

U-M Health System study finds patient education video is excellent teaching tool but doctors are better at calming fears

In an age when people often learn health information from surfing the Web and watching television shows set in hospitals, researchers have found that showing patients an educational video about their condition teaches them the facts about their disease even better than when their doctor tells them about the condition.

But the power of videotaped infor

A mixture of bacteria developed in part by University of Alberta researchers has been proven highly effective in treating people suffering from ulcerative colitis.

The findings, published in the July, 2005 issue of American Journal of Gastroenterology showed that the majority of patients taking a probiotic mixture of 8 bacteria (VSL#3) for 6 weeks improved their ulcerative colitis. Probiotics are preparations of living microbial cells that, when ingested, are thought to posit