Research notes

What works to keep weight off?

Suzanne Phelan made a media splash last month after presenting a weight-loss paper at the annual meeting of the North American Association for the Study of Obesity.

Phelan, an assistant professor of psychiatry at the Medical School and a staff psychologist at The Miriam Hospital, is co-principal investigator of the National Weight Control Registry, a database of about 5,000 people who've lost at least 30 pounds and kept the weight off for at least a year.

With nine years of data to mine, Phelan wanted to see whether successful weight loss strategies had changed over time. The answer: More weight losers eat a diet that is higher in fat and lower in carbohydrates. Phelan said this phenomenon is likely due to the popularity of low-carb diets.

Phelan said that dieters on low-carb or low-fat diets had equal success in losing weight as long as they were consistent. But the people most likely to regain weight consumed more calories, ate more fat, and stopped exercised regularly.

Her findings were picked up by news outlets around the country, including USA Today and CNN. Phelan was surprised. "This is not earth-shattering news," she said. "If you want to keep weight off, keep your fat intake low, keep your calories down and exercise. This message has been around for a long time."

Improvements in nursing home pain management

Researchers from the Center for Gerontology and Health Care Research at the Medical School published an innovative study in the December issue of the Journal of the American Geriatrics Society. Community health professors and research staff - Joan Teno, David Gifford, Therese Rochon and Debra DeSilva - teamed up with health care improvement experts at Quality Partners of Rhode Island to improve pain management in nursing homes.

The team found that a comprehensive, collaborative improvement process - one that quickly changes how staff assess and treat pain - produces results. In the 17 Rhode Island nursing homes studied, researchers found a 41 percent drop in pain among residents. Comparatively, all 95 nursing homes in Rhode Island only had a 12 percent reduction in pain during the study period.

Rosa Baier, a project manager at Quality Partners who recently earned her master's degree in public health at Brown, was the lead author of the study. Baier said nursing homes' success was due to the multifaceted nature of the improvement plan, which included mentoring and staff training. Staff also tested several pain-relief strategies ranging from more frequent pain assessments to aromatherapy and massage.

"We know we have to improve pain management Ð and we know what evidence-based strategies can get us there," said Gifford, medical director of Quality Partners and associate professor at Brown Medical School. "What we've shown is that when an organization puts these strategies in place, they get results."

The riddle of the sea urchin egg

Sea urchin eggs, a common model for human fertility research, create a protein shield just minutes after fertilization. In the December issue of Developmental Cell, Brown biologists Julian Wong, Gary Wessel and Robbert Creton revealed their discovery of an enzyme that generates hydrogen peroxide, a free radical critical to this protective process.

Their finding solves a century-old biology riddle. In most animals, such as sea urchins, fish, mice and humans, only one sperm fertilizes an egg. If multiple sperm fuse with the egg, a process known as polyspermy, the embryo will die. So the fertilized egg quickly creates protective barriers. Scientists have known for more than 30 years that, in sea urchins, hydrogen peroxide is a key player in this process. Until now, they didn't know how that potentially toxic substance was produced or controlled.

Wessel said that human eggs also create a barrier against polyspermy after fertilization. While the production of peroxide in this process hasn't been proven in humans, Wessel said scientists suspect a similar process occurs. If true, a damaged or missing peroxide-producing gene could explain one source of infertility.

Wong, a Brown research associate and lead researcher on the project, set out to find the gene responsible for pumping out this peroxide. In the Sea Urchin Genome Project database, Wong found a gene that he suspected was key for this process because it looked similar to one that produces peroxide in the human thyroid.

After a series of experiments using sea urchins, Wong found that his guess was correct. While the egg matures, this gene is turned on and creates an enzyme known as urchin dual oxidase, or Udx1. Immediately after fertilization, Udx1 is activated to produce peroxide. The peroxide is then used to "stitch" together proteins on a thin layer surrounding the egg, hardening it into a tough coating. The process is complete about five minutes after fertilization.

Compiled by Wendy Y. Lawton