Health Report: Apr. 18, 1994

THE GOOD NEWS

-- A protein that plays a crucial role in Alzheimer's may hold the key to developing a test for early detection of the disease. The protein, beta amyloid, destroys a brain cell's ability to regulate potassium, the chemical that triggers signals governing memory. Since the protein also affects other cells, scientists hope to develop a skin test to detect the onset of Alzheimer's.

-- Alzheimer's sufferers received another ray of hope in the finding that the drug tacrine can significantly -- though temporarily -- improve memory. Unfortunately, tacrine in high doses can damage the liver and cause such other side effects as nausea.

THE BAD NEWS

-- Some domestic cats in the rural Southwest have become carriers of human plague. A new report says the cats can pick up the disease from rodents or fleas and transmit it via licks, bites or scratches. Only 15 cases of plague have been traced to cats, however, and such simple precautions as removing trash where rodents thrive can limit risk to humans.

-- A panel of experts has concluded that standard screening tests for ovarian cancer are too imprecise to justify their costs. Blood tests and ultrasound often produce false alarms, which prompt doctors to perform unnecessary exploratory surgery.

Sources -- GOOD: Journal of the American Medical Association; Science. BAD: Centers for Disease Control and Prevention; National Institutes of Health.