Shock resistance
The bodies of most teenage women are well protected against toxic shock syndrome (TSS)—an infection associated with the use of tampons. And African-Americans of any age are slightly more susceptible than whites and Hispanics. Those are key findings of a new DMS study. Infectious disease specialist Jeffrey Parsonnet, M.D., and colleagues looked at ratios between the bacterium that causes TSS and the antibodies that fight it in 3,012 menstruating North American women aged 13 to 40. Since 70% of women in the United States, Canada, and much of Western Europe use tampons, the team noted, TSS—although rare—remains of interest.

Birthright
Low birth weight is closely tied to where a baby is born, found a recent DMS study. Even after adjusting for socioeconomic status, race, and the mother's health, threefold variations persisted in this key risk factor for infant mortality. The researchers plan to "look more closely at the types of available care and the services received by women in these regions," says DMS pediatrician David Goodman, M.D. "The areas with better-than-expected rates of low birth weight may be regions with better reproductive and perinatal services."

Smoke screen
When movie stars light up, adolescents often follow suit, according to the first national study to look at the connection between smoking in movies and smoking initiation. After adjusting for other influences, DMS researchers found that adolescents with the highest exposure to smoking in movies were 2.6 times more likely to smoke than those with the lowest exposure. Onscreen smoking "is a very strong social influence on kids ages 10 to 14," says DMS pediatrician James Sargent, M.D. "Its impact on this age group outweighs whether peers or parents smoke or whether the child is involved in other activities, like sports."

Dirty pool
Cholera—a bacterial disease that's transmitted through contaminated drinking water—relies on a single gene and protein to colonize the human intestine, DMS researchers reported in Nature. "We've identified a factor that works both in the environment and in the human body," stated Ronald Taylor, Ph.D., who led the research. Though a vaccine for cholera exists, it's effective only 50% of the time. This finding "has a strong potential for vaccine and therapeutic development," according to Taylor, whose group will continue to look for other ways cholera bacteria infect humans.

Age-old disparities
Elderly blacks receive fewer life-saving surgeries than whites, researchers from DMS and Harvard reported in the New England Journal of Medicine. The team looked at how often certain high-cost operations—such as coronary artery bypasses—were performed on Medicare enrollees from 1992 to 2001. In all 158 hospital-referral regions the group examined, rates were higher for whites. "We found no evidence," wrote DMS's Elliott Fisher, M.D., M.P.H., and colleagues, "either nationally or locally, that efforts to eliminate racial disparities in the use of high-cost surgical procedures were successful."

Hip-huggers
Elderly patients who have elective hip replacements live longer than their counterparts. But why? Does the surgery itself make a difference? Or are patients who choose surgery healthier to begin with? A group of DMS biostatisticians found that hip replacement patients do indeed start out healthier, with a 30% lower prevalence of most serious diseases. But even after adjusting for that fact, the life-prolonging effects of the surgery persisted. "Some effect of the procedure itself cannot be ruled out," researcher Jane Barrett, M.Sc., and her team concluded.

Revealing genes
Advanced testicular cancer can often be cured with conventional chemotherapy, and DMS pharmacologists are trying to find out why. In the journal Oncogene, they revealed 46 genes that are upregulated by chemotherapy and five that are repressed. Several of the upregulated genes are known to be affected by another gene, called p53. The activation of p53, the researchers now believe, is linked to testicular cancer's hypersensitivity to chemotherapy. "Many of the gene products" identified in this study "may participate in the unique curability of this disease," they concluded.

Enough is enough
Giving heart-surgery patients anti-inflammatory hormones—a common practice—may have limited benefit, says a study from DMS. The body produces enough of the anti-inflammatory hormone cortisol on its own during and after surgery, researchers found in a study of 60 patients. Patients who received antiinflammatory medication—glucocorticoids (GCs)—did have more anti-inflammatory agents in their blood, but there were "no identifiable clinical differences between the treatment groups," reported lead author Mark Yeager, M.D., and his coauthors in the journal Critical Care Medicine.

Joseph Cravero, M.D., studied 10,552 pediatric sedation cases and found a near zero rate of severe injury; rates of minor problems were lower for anesthesiologists than for other specialists.

An analysis of myths about irritable bowel syndrome by Brian Lacy, M.D., Ph.D., showed that 43% of 261 patients think it's caused by food allergies and 68% by depression.

Scientists in Dartmouth's Toxic Metals Research Program, with colleagues at SUNY-Stony Brook, got a $1.4-million grant to study how heavy metals move through the food web in estuaries.

A paper on circadian rhythms by Hildur Colot, M.A., a research associate in genetics, was highlighted for its special significance in the "In-Cytes" section of Molecular Biology of the Cell.