Medical digest: Study warns of ibuprofen, aspirin mix
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BOSTON — The popular pain reliever ibuprofen blocks the heart-protecting effects of aspirin, according to a study that sounds a warning for people who take both medicines.
"It would not do you a lot of good to take one medication only to have another wipe out its effects," said Dr. Muredach Reilly, a University of Pennsylvania cardiologist who took part in the 30-patient study reported in today's New England Journal of Medicine.
Many heart patients regularly take aspirin because it thins blood and prevents clots that cause heart attacks. Ibuprofen, in Motrin and Advil, is used widely for arthritis and other aches and pains.
In the study, when patients took a single dose of ibuprofen beforehand, aspirin lost 98 percent of its blood-thinning power. When aspirin was taken first, three daily doses of ibuprofen sapped aspirin of 90 percent of its benefit.
The researchers think ibuprofen clogs a channel inside a clotting enzyme known as cyclooxygenase-1. Aspirin becomes stuck at the bottleneck and cannot reach its active site inside the enzyme.
The study, funded partly by the National Institutes of Health and aspirin maker Bayer, found no conflict between aspirin and three other arthritis drugs: rofecoxib, diclofenac and acetaminophen, the active ingredient in Tylenol.
But the researchers suggested that other drugs with ibuprofen-like structures, such as indomethacin, similarly will block aspirin.
Researchers think they've unraveled French Paradox
Researchers say they have discovered the key component in red wine that explains the so-called French Paradox, or the way the French can eat lots of cheese, buttery sauces and other rich foods and still suffer less heart disease than Americans.
The explanation is pigments known as polyphenols.
The pigments are not present in white wine or rosé, and they seem to be less potent when present in grape juice.
Polyphenols inhibit the production of endothelin-1, a peptide that contributes to hardening of the arteries, researchers from the London School of Medicine & Dentistry report in today's issue of the journal Nature.
Red grape juice, which has plenty of the pigment, was markedly less potent in reducing endothelin-1 than red wine. The researchers suggested that something in the winemaking process changes the pigment's properties.
Researchers think the pigment comes from red wine skins. In white wine and rosé, the grape skins are taken out before fermentation.
Human Genome Project maps chromosome 20
British scientists have mapped chromosome 20, the third and longest chromosome to be sequenced in the Human Genome Project.
Chromosome 20 is best known for harboring genes that contribute to forms of the brain-wasting Creutzfeldt-Jakob disease and severe-combined immunodeficiency, an illness in which the immune system is crippled.
Genes on chromosome 20 also have been linked to various cancers and some metabolic disorders, including type 2 diabetes and obesity, and Graves' disease, a thyroid disorder.
Chromosome 20 contains 727 genes and accounts for about 2 percent of the total human genetic material, according to researchers at the Wellcome Trust Sanger Institute in Cambridge, Mass. The map is published in today's issue of the journal Nature.
Risks thought to be less in newer birth-control pills
BOSTON — The latest generation of birth-control pills appears to carry a smaller risk of heart attack than its predecessor, a Dutch study found.
The study of 1,173 women found that those who took second-generation pills had 2½ times the heart-attack risk of other women. But women who took the current, third-generation pills essentially had the same risk as other women, according to findings published today in The New England Journal of Medicine.
Second-generation pills, which often carry the hormone levonorgestrel, date to the 1970s. Third-generation contraceptives, which often contain desogestrel or gestodene, became available in the United States mostly in the 1990s.
Doctors said women should not necessarily switch to the newer pill. For one thing, an earlier study came to an opposite conclusion.