CHECKUP UCLA MEDICAL EARNS ACCOLADES.

Byline: - Staff and wire reports

UCLA Medical Center was named one of the nation's most outstanding hospitals in the 2002 U.S. News and World Report rankings.

The rankings, published in the July 22 issue, looked at 17 specialties, including cancer, pediatrics, heart surgery and geriatrics. The Johns Hopkins Hospital in Baltimore topped the list, with UCLA Medical Center ranked fifth.

Six other medical centers received high rankings in specific categories.

Childrens Hospital Los Angeles ranked 11th for pediatrics. Kaiser Foundation Hospital in Los Angeles placed 30th in rheumatology. Los Angeles County-Harbor UCLA Medical Center in Torrance came in 30th for hormonal disorders. Los Angeles County-King Drew Medical Center ranked 28th in geriatrics. Los Angeles County-USC Medical Center placed 31st in gynecology, 48th in neurology and neurosurgery, and 39th in rheumatology. And Rancho Los Amigos National Rehabilitation Center in Downey was ninth in rehabilitation. For more information, visit www.usnews.com.

OBESITY LINK: The hormone leptin, linked to appetite control, may hold the key to treating obesity, UCLA researchers have found. Dr. Julio Licinio, professor of medicine, conducted a study on three adults from Turkey with a rare genetic mutation that prevents their bodies from producing leptin. After 10 months of leptin therapy, all three lost half of their body weight - more than 150 pounds each.

Scientists have looked at leptin before, but discovered that many obese people produce too much of the hormone and that their bodies stop responding to appetite cues. However, in some cases people become obese because they manufacture too little leptin.

Leptin plays an important role in the human body, controlling appetite by signaling fullness. Further research at UCLA will examine such areas as the interactions of leptin and other hormones in the elderly and how leptin replacement influences the human endocrine system.

BREATHE EASIER: Your risk of catching a cold while traveling is no greater on newer airplanes that recirculate cabin air than in older ones that pump in fresh air from the outside, claims a new study published recently in the Journal of the American Medical Association.

Modern jets recycle about half their cabin air as a way to reduce strain on the engines and improve gas mileage. Many older planes, though increasingly obsolete, use 100 percent compressed fresh air to ventilate the seating area.

Studies have shown that poorly ventilated spaces - such as airplanes and office buildings - can increase the risk of germ and virus transmission. While airplanes that recirculate their cabin air have fine filters to trap pathogens, experts have wondered whether the technology might put passengers at risk of disease by steeping them at least partly in other people's breath.

The answer, according to the latest study, is no.

A research team led by an assistant clinical professor of medicine at the University of California, San Francisco, compared rates of colds and other respiratory ailments in 1,100 air travelers going between San Francisco and Denver in 1999. Slightly more than half flew in new jets with air-recycling systems.

Within a week of their trip, 19 percent of the group that had flown on a new plane complained of a cold, compared with 21 percent of the other passengers - a statistically insignificant difference, the researchers say. Rates of runny nose and cold together - 10 percent vs. 11 percent - and one strict definition of illness, a cluster of eight upper-respiratory symptoms (3 percent), were also identical.