A strong link exists between lifetime exposure to ultraviolet light, particularly lifetime sunburns, and the development of melanoma – the most lethal form of skin cancer.

Now, for the first time, scientists have identified a specific molecular pathway within cells that becomes mutated by ultraviolet light exposure, thereby speeding up melanoma development.

New findings published in the Feb. 4 issue of Proceedings of the National Academy of Sciences may have implications fo

The first laboratory population study of genetically modified mosquitoes identifies issues that need to be faced in the task of turning mosquitoes from disease carriers into disease fighters.

Scientists from Imperial College London report in Science today that populations including genetically modified mosquitoes quickly lose their test marker gene when they are bred with unmodified mosquitoes.

The scientists say their results have several lessons for further work on developing GM m

Researchers from the University of Pennsylvania and the University of Sheffield report in the Feb. 21 issue of Science that they have created tree-like molecules that assemble themselves into precisely structured building blocks of a quarter- million atoms. Such building blocks may be precursors to designing nanostructures for molecular electronics or photonics materials, which “steer” light in the same way computer chips steer electrons.

Virgil Percec, the P. Roy Vagelos Chair and Profes

B cell chromatin study strikes physiological chord

Some cells sing with the chorus, while others unwittingly achieve fame on their own. The immune system’s B cell is a true diva that spends its early days preparing for the ultimate audition. Its repertoire of possible antibodies to invading microbes totals 50 million. For the immune system, this repertoire means the difference between destroying a potentially lethal antigen or not.

Since the late 1970s, the genes for makin

Greater insight into human brain disease may emerge from studies of a new genetic mutation that causes adult fruit flies to develop symptoms akin to Alzheimer’s disease.

“This is the first fruit fly mutant to show some of the outward, physical manifestations common to certain major human neurodegenerative diseases,” said principal investigator Michael McKeown, a biology professor at Brown University.

A research team found the mutation in a gene they named “blue cheese.” Reporting i

Increasing hormone causes increase of appetite, eating

Researchers at Oregon Health & Science University (OHSU) have identified a key hormone involved in appetite control and demonstrated its effect on the brain. Scientists have shown that the hormone, called ghrelin, activates specialized neurons in the hypothalamus involved in weight regulation. The research involved scientists at several collaborating institutions, including: Yale Medical School, Baylor College of Medicine, the Uni

Forget sharp metal picks or X-rays-in the future, your dentist may search for cavities using a painless laser-based technique developed at U of T that can detect cracks or defects at an early stage of development. v “Using the technique, we can see all the way to the pulp-more than five millimetres inside a tooth,” says Professor Andreas Mandelis of U of T’s Department of Mechanical and Industrial Engineering. “It can reveal suspicious regions invisible to the naked eye below the surface of

Dr. Kouros Motamed is studying endothelial cells where they live, in the complex environment that provides, not only support and structure, but regulation and direction.

As he studies these cells that line blood vessels, this vascular biologist at the Medical College of Georgia focuses on the proteins and growth factors that regulate their normal processes, including proliferation, differentiation, migration and death.

He wants to better understand how these cells interact with th

A common genetic variant influences individual responses and adaptation to pain and other stressful stimuli and may underlie vulnerability to many psychiatric and other complex diseases, reports David Goldman, M.D., Chief, Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, and colleagues at NIAAA and the University of Michigan. COMT val158met Genotype Affects m-Opioid Neurotransmitter Responses to a Pain Stressor appears in the February 21 issue of Science (299:1240, 200

The universe has been mapped! Not the universe of stars, planets, and black holes, but the protein universe, the vast assemblage of biological molecules that are the building blocks of living cells and control the chemical processes which make those cells work. Researchers with the Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California at Berkeley have created the first three-dimensional global map of the protein structure universe. This map provides important insight i

Montreal Neurological Institute researcher Dr. Wayne Sossin has discovered that nerve cells can bypass the cell’s normal protein-making machinery in the same way that viruses do when they infect a cell. In a study published on-line today in Nature Neuroscience, Dr. Sossin and colleagues describe the first example of regulated IRES (internal ribosome entry site) usage after a physiological stimulus in neurons.

When a virus infects a cell, its goal is to make more virus particles. To do t

Since the 1980s most experts have assumed that heterosexual sex transmitted 90% of HIV in Africa. In the March International Journal of STD and AIDS, an international team of HIV specialists presents groundbreaking evidence to challenge this consensus, with “profound implications” for public health in Africa.

In a series of articles, Dr David Gisselquist, Mr John Potterat and colleagues argue that the spread of HIV infections in Africa is closely linked to medical care. In their unique stud

A Mediterranean diet significantly lessens the symptoms of rheumatoid arthritis, shows a small Swedish study in the Annals of the Rheumatic Diseases. But it takes a minimum of six weeks for the diet to take effect, the study shows.

The researchers were only able to study 51 people out of a possible 300, because of the various combinations of drugs patients were taking. In the end, 26 people with stable rheumatoid arthritis were assigned to an experimental Mediterranean/Cretan, diet for three

The effect of spinal cord stimulation, in chronic pain treatment, can be drastically improved using continuous distance detection. The strength of the stimulation pulses then depends on the distance measured between the electrodes and the spinal cord. In this way, negative side-effects belong to the past. These side-effects arise with a varying distance, causing diminished pain treatment in case of a distance that is too large, or unwanted sensations when the distance is too small. Emiel Dijkstra of

Tamoxifen appears to reduce the risk of benign breast disease and may result in fewer biopsies, according to an analysis of data from a major randomized clinical trial of tamoxifen. The findings appear in the February 19 issue of the Journal of the National Cancer Institute.

Tamoxifen was shown in the Breast Cancer Prevention Trial to reduce the incidence of invasive and noninvasive breast cancer by as much as 50% compared to placebo. Other studies have suggested that tamoxifen can also dec

We all know people who can take pain or stress much better than we can, and others who cry out at the merest pinprick. We’ve heard stories of people who did heroic deeds despite horrible injuries, and stereotypes about women’s supposedly sensitivity to pain that don’t mesh with their ability to withstand childbirth’s pain.

But what accounts for all these differences in how individuals feel and respond to pain? And why are some people, especially women, more frequently pr