Combined hormone replacement therapy boosts stroke, dementia

Last March, a multi-center national study made headlines by concluding that taking a combination of the hormones estrogen and progestin did not improve the quality of life for women who are free of menopause-related symptoms but did expose them to a slightly higher risk of heart attacks, strokes and breast cancer. For that reason, many medical scientists began recommending against the combined therapy in the absence of such symptoms, saying the risks of estrogen plus progestin outweighed the benefits.

Hidden chlamydia epidemic found in China

Researchers at the University of North Carolina at Chapel Hill School of Medicine have helped identify a large, undetected epidemic of the sexually transmitted disease chlamydia in China. The new findings appear in the Journal of the American Medical Association. The collaboration involving UNC, the University of Chicago and researchers in China points to a chlamydia epidemic that developed in that country during the last 20 years ? and represents the first nationwide study of its kind to combine reported behavior with physical evidence of the consequences of sexual activity.

Study may help explain sunlight's role in melanoma development

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.

HIV-positive inmates say often have unprotected sex before, after release

Inmates infected with HIV, the virus that causes AIDS, engaged in unprotected sex both before imprisonment and after their release at “exceedingly high rates,” according to a new University of North Carolina at Chapel Hill School of Medicine study. Seventy-eight percent of N.C. men and women prisoners carrying the virus who had a main sex partner reported unprotected sex with that person in the year before they were locked up, the study showed. Twenty-six percent of them interviewed again soon after release admitted to already having sex without condoms with their main sex partners.

Researchers turn rat stem cells into mouse marrow cells

Researchers in North Carolina have successfully demonstrated that genetically altered stem cells from one species can be turned into a different sort of cell in another. Specifically, the researchers converted adult liver stem cells cloned from a male rat into functional adult bone marrow cells in female mice. The accomplishment, known as hematopoietic transdifferentiation, may prove useful for tapping the potential for tissue repair using human adult stem cells.

Vigorous leisure activity may reduce risk of preterm birth

Women who engage in vigorous leisure activity during their first and second trimesters of pregnancy may experience a decreased risk of preterm birth, a new study suggests. Vigorous leisure activity includes exercise programs such as swimming laps, jogging at a moderate to fast pace, aerobics or aerobic dance, other fast dancing and moderate to fast bicycling. Preterm birth is defined as delivery before completion of 37 weeks gestation.

Nearness of markets boosts people’s intake of nutritious fruits and vegetables

Black Americans’ fruit and vegetable intake increased by 32 percent for each additional supermarket in the neighborhoods where they lived, according to a new University of North Carolina at Chapel Hill School of Public Health study. White Americans’ fruit and vegetable consumption increased by 11 percent with the presence of one or more supermarket in their neighborhoods, the study showed. “We don’t know why we saw a larger influence of supermarkets on the diets of black Americans compared to white Americans,” said Dr. Kimberly Morland of the Mt. Sinai School of Medicine. “Based on our previous research showing a lack of private transportation in predominately black neighborhoods, we suspect that white Americans may have a larger geographic area in which to select places to patronize.