Findings
Updated: 2013-04-07 07:44
(The New York Times)
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Coffee: Not just caffeine
People who live on the Greek island of Ikaria are known to have remarkably high life expectancies, and researchers have been studying them carefully to learn why. Now a new report suggests that one reason may be the coffee they drink.
"This boiled coffee seems to generate antioxidant substances," said Dr. Gerasimos Siasos, a professor at the University of Athens Medical School and an author of the study, which appears in the journal Vascular Medicine.
He and his colleagues found that older islanders who drank the boiled coffee had better functioning endotheliums - the layer of cells that line blood vessels.
"When there is dysfunction here, the arteries become more stiff, and we have heart attacks and arterial occlusions," said Dr. Siasos, who did the research with a colleague.
Coffee is only one factor. "It has to do with their way of living," Dr. Siasos said. "People sleep over eight hours a night, there is increased socializing, and they have much less stress than people in Athens."
The islanders also eat a Mediterranean diet that includes many fruits, vegetables, olive oil and fish. Most also nap every day and walk and garden regularly, Dr. Siasos said.
The researchers will journey to Ikaria this summer to study how the island's water, minerals and air quality might also be contributing to longevity.
SINDYA N. BHANOO
Aspirin and skin cancer
Researchers report that a woman's regular use of aspirin may decrease her risk of melanoma, the most serious kind of skin cancer.
The study, published online in the journal Cancer, included 59,806 women ages 50 to 79. Researchers gathered health and lifestyle data at the start of the study, and the women reported their health in yearly questionnaires over an average 12 years of follow-up. The women brought in their medicine bottles for the researchers to examine and record.
There were 548 incidents of melanoma during the period. After controlling for sun exposure, sunscreen use, a history of skin cancer and many other factors, the researchers found that women who reported using aspirin had an average 21 percent lower risk of melanoma compared with nonusers, and the longer they used aspirin, the lower their risk.
The reasons for the effect are unclear, but the authors suggest that aspirin's known effect in promoting cell death and activating tumor suppressor genes may be factors.
The senior author, Dr. Jean Y. Tang, an assistant professor of dermatology at Stanford University in California, said the study was observational, not a clinical trial, and that correlation does not equal causation.
"It's an important finding for high-risk women to discuss with their doctors," Dr. Tang said, adding, "but it's way too early to recommend that everyone go take aspirin to prevent melanoma."
NICHOLAS BAKALAR
Wolf's perplexing origin
The Falkland Islands wolf, long extinct, is the only land-based mammal native to the islands. European explorers in the 17th century were puzzled by the presence of this lone mammalian species, as was Charles Darwin.
Now, researchers writing in Nature Communications suggest that the wolf traveled across a thin, shallow strait from the mainland to the islands during the last glacial maximum. During this period, about 18,000 to 25,000 years ago, the strait would periodically freeze over.
"This wolf was likely tracking penguins, seals and sea birds that were hauling out onto the ice," said Dr. Alan Cooper, an evolutionary biologist at the University of Adelaide in Australia.
The scientists believe the wolf crossed the strait from what is now Argentina. "The question is, how did this great big mammal get over when rodents didn't?" he said.
Dr. Cooper and his colleagues compared DNA samples from the wolf with those of one of its closest mainland relatives, an extinct foxlike species called Dusicyon avus. They found that the two species separated about 16,000 years ago, coinciding with the last glacial maximum and the frozen marine strait.
Previously, it had been theorized that the wolf was semi-domesticated and brought to the island by humans.
The last Falkland Islands wolf was spotted in the late 19th century.
SINDYA N. BHANOO
(China Daily 04/07/2013 page11)