Results from a new study in laboratory mice show that nighttime exposure to artificial light stimulated the growth of human breast tumors by suppressing the levels of a key hormone called melatonin. The study also showed that extended periods of nighttime darkness greatly slowed the growth of these tumors.

The study results might explain why female night shift workers have a higher rate of breast cancer. It also offers a promising new explanation for the epidemic rise in breast c

Polio is on track to become only the second disease ever eradicated. In two studies in the Dec. 15 issue of The Journal of Infectious Diseases, now available online, scientists are working to ensure that once it is gone, it stays gone. One study reduces concerns that people whose immune systems were weakened by HIV would re-introduce poliovirus into the community. The other study looks at the how switching forms of vaccine from a live, attenuated vaccine to an inactivated version may affect

Discovery in rodents may explain why some antidepressants require weeks of use before they work

The beneficial effects of a widely used class of antidepressants might be the result of increased nerve-fiber growth in key parts of the brain, according to a Johns Hopkins study being published in the January 2006 issue of the Journal of Neurochemistry.

The study on rats, led by Vassilis E. Koliatsos, M.D., a neuropathologist at the Johns Hopkins University School of Medicine,

A derivative of the sweet wormwood plant used since ancient times to fight malaria and shown to precisely target and kill cancer cells may someday aid in stopping breast cancer before it gets a toehold. In a new study, two University of Washington bioengineers found that the substance, artemisinin, appeared to prevent the onset of breast cancer in rats that had been given a cancer-causing agent. The study appears in the latest issue of the journal Cancer Letters.

“Based on earli

Research from the Friedman School of Nutrition Science and Policy at Tufts University

With the population of the world increasing rapidly, the number of people aged 60 years and older is expected to nearly triple by 2050. The majority of these elderly people will be living in the developing world, where the burden of disease is greater. In a special article published in Nutrition Reviews, researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) at Tufts

Novel computational neuroscience model offers new areas for experimentation

Our ability to understand speech or decide which fruit in the store is freshest depends on the brain’s dexterity in integrating information over time. The prefrontal cortex, where working memory resides, plays a critical role in helping us make these countless everyday decisions. A novel computational study by Brandeis researchers in this week’s issue of the Proceedings of the National Academy o

There is a strong, progressive association between tooth loss and heart disease, researchers report in a study published in the latest issue of American Journal of Preventive Medicine.

Heart disease was present in 4.7 percent of those without tooth loss, 5.7 percent of those with 1 to 5 missing teeth, 7.5 percent of those with 6 to 31 missing teeth, and 8.5 percent of those with total tooth loss, reports lead investigator Catherine Okoro, epidemiologist in the Division of Adult

Almost half of lung cancers detected by a chest x-ray were early-stage cancers, according to baseline results of a large, randomized clinical trial that is testing the efficacy of a chest x-ray as a screening test for lung cancer. The study results are published in the December 21 issue of the Journal of the National Cancer Institute.

Lung cancer causes one million deaths worldwide every year. When patients begin to experience symptoms of lung cancer, the cancers are often ad

A decreased ability to repair chromosomal damage caused by exposure to ultraviolet B (UV-B) radiation in test tubes may be associated with an increased risk of the common skin cancers basal cell carcinoma and squamous cell carcinoma, but not of melanoma, according to a study in the December 21 issue of the Journal of the National Cancer Institute.

Exposure to UV radiation from sunlight is a risk factor for the two most common skin cancers, basal cell carcinoma and squamous cell carcinom

When it comes to the information in a mammogram, Purdue scientists say less is more – and their findings could bring medical care to many far-flung communities.

A team of researchers, including Bradley J. Lucier, has found that digitized mammograms, the X-ray cross sections of breast tissue that doctors use to search for cancer, are actually interpreted more accurately by radiologists once they have been “compressed” using techniques similar to those used to lessen the memory deman

New York University School of Medicine researchers provide some of the most compelling evidence yet that long-term exposure to air pollution–even at levels within federal standards–causes heart disease. Previous studies have linked air pollution to cardiovascular disease but until now it was poorly understood how pollution damaged the body’s blood vessels.

In a well-designed mouse study, where animals breathed air as polluted as the air in New York City, the researchers pi

A new study supports previous research done that used guided health imagery to help smokers quit. Guided health imagery – a technique to help patients relax their muscles and open their minds to images of health and healthy living – has long been used to help surgery and cancer patients, as well as for reducing pain and reversing negative thoughts resulting from traumatic events including rape and other types of sexual assault.

This study, published in the Journal of Nursing Scholars

JBS 2: Joint British Societies’ guidelines on prevention of cardiovascular disease in clinical practice

New joint guidelines published by six professional societies today in Heart significantly widen the criteria for prevention of heart disease and stroke in primary care, and are set to boost the numbers of patients targeted for screening and preventive treatment.
The evidence based guidelines are a collaborative effort from the British Cardiac Society, the British Hyper

Researchers have discovered that drugs, such as heart burn medications, which reduce gastric acidity, are potential risk factors for Clostridium difficile infection outside of hospitals. The new research to be published in the Journal of the American Medical Association (JAMA) tomorrow focuses on community-acquired C. difficile, and is a follow-up to previous work by the same group that demonstrated an increased risk from these medications in hospital settings.

“We believe drugs that reduc

In recent years horizontal, or lateral, gene transfer has been seen frequently in prokaryotes and also occasionally in eukaryotes. This lateral transfer involves the movement of genetic material between species as opposed to the vertical transfer of genes from parent to progeny. Horizontal transfer has been observed between the mitochondrial DNA of different plant species. Until now, however, no one had found evidence for horizontal transfer in the nuclear DNA of plants.

In a new

At the Institut Curie, an Inserm team has just identified the molecular mechanism long suspected to account for the formation of malignant cells in the most frequent leukemia – acute myeloid leukemia. For a cell to become leukemic, it must not only proliferate but also no longer become specialized. Mutations in its gene confer autonomous activity on the Kit receptor, thereby allowing cells to proliferate in the absence any external signal.This study was published in the 12 December 2005 issue