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RESCUING BRAIN CELLS FROM THE BRINK OF SUICIDEFor several days after a patient suffers a stroke, brain cells are bombarded with molecular "pro-death" signals carrying such bad news about their environment that the cells are tempted, even urged by other molecules, to commit suicide.Many do. It's the main reason most strokes aren't limited to a tiny area of the brain but damage a larger region as well. Now, in a bid to give faint-hearted brain cells the will to live, scientists have enlisted an unlikely ally: the herpes virus. In an article published in the Journal of Neuroscience, a Rochester team announced a series of experiments in which it used the virus to modify brain cells of mice, making the cells more resistant to death after a stroke. Like psychologists talking a despondent man down from the ledge, the scientists kept cells from suicide by thwarting the molecular machinery--a process known as apoptosis--normally involved in persuading them to self-destruct. Once the brain has been traumatized by the low oxygen levels, or hypoxia, that stroke causes by choking off the blood supply, it unleashes a flurry of molecular signals encouraging still-healthy cells to kill themselves, magnifying the effects of the initial attack. The widespread self-destruction takes place for days or even a week after the initial stroke. It's a big reason why strokes are the leading cause of long-term disability in the United States, where there are about 4 million stroke survivors, roughly the same number as those who have Alzheimer's disease. "Stroke is all about how cells deal with hypoxia," says neuroscientist Howard Federoff, who did the study with graduate student Marc Halterman and dermatologist Craig Miller.
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