Ibuprofen May Counteract Effect of Aspirin
The ibuprofen that you take to ease arthritis pain can counteract the aspirin that you take to protect your heart, according to researchers at the University of Pennsylvania School of Medicine.
Dr. Garrett A. FitzGerald and his colleagues reported in the Dec. 20 issue of the New England Journal of Medicine that the two painkillers bind at nearly the same site on the COX-1 enzyme, which plays a role in blood clotting.
Aspirin binds irreversibly to COX-1, dramatically impairing the ability of platelets to form clots. Ibuprofen, which binds less strongly and for shorter periods of time, has only a minor effect on clot formation.
Working with volunteers, FitzGerald’s group found that by first administering ibuprofen, the action of aspirin is blocked.
Administering aspirin first allows it to work properly. But when ibuprofen is given in the doses usually used by arthritics--three times a day--enough is left in the bloodstream the next day to block aspirin’s action.
The same effect was not observed with the over-the-counter painkiller diclofenac or with the prescription drug Vioxx. The study was sponsored by the National Institutes of Health and Bayer.
“Patients taking aspirin to protect against heart attack should seek the advice of their doctors before commencing additional treatments for pain or inflammation,” FitzGerald said.
Carcinoids Could Increase Risk of Other Cancers
People with a type of colorectal cancer called carcinoids have an unusually high risk of developing other types of cancer, according to a new study.
Colorectal cancer strikes 140,000 Americans annually, causing 60,000 deaths. Carcinoids, tumors of the small intestine, account for about 1% of colorectal tumors.
Using a National Cancer Institute database, Dr. David S. Tichansky and his colleagues at Jefferson Medical College and Thomas Jefferson University Hospital in Philadelphia analyzed 2,086 carcinoid patients diagnosed with the disease between 1973 and 1996. They then compared their incidence of selected tumors with the incidence in the population as a whole.
The team reported in the January issue of Diseases of the Colon & Rectum that patients with carcinoids were more than seven times more likely to develop additional colorectal tumors, 38 times more likely to develop small bowel tumors, and more than two times more likely to develop cancers of the lung, esophagus, urinary tract and prostate.
After their treatment, Tichansky said, patients with carcinoids should be monitored carefully for the development of other cancers.
Researchers Explore Benefits of Red Wine
Researchers may have discovered how red wine protects against heart disease, helping to explain the so-called French paradox--that the French can eat cheeses, sauces and other foods high in cholesterol and still suffer less heart disease than Americans. The secret seems to lie in pigments called polyphenols, which are present in red wine but not white wine or rose, and which seem to be less potent in grape juice.
In laboratory tests with cells from the blood vessels of cows, researchers from the London School of Medicine & Dentistry found that red wine reduced the amount of a chemical called endothelin-1, which is released by the blood vessels. The reduction was proportional to the amount of polyphenols present.
Endothelin-1 is a potent blood vessel constrictor; its overproduction is thought to be a key factor in the clogging of arteries by fat deposits.
The team reported in the Dec. 20 issue of Nature that white and rose wines have virtually no effect on endothelin-1 levels, and that grape juice has only a modest effect.
Vaccine May Prevent Urinary Infections
A new vaccine may prevent recurrent urinary infections in many women who have several bouts of the infection each year.
The vaccine, a vaginal suppository that is given monthly, does not provide long-lasting immunity. But taking it monthly is a better alternative than constantly taking antibiotics, said Dr. Walter Hopkins of the National Institutes of Health, who conducted the research.
The vaccine consists of 10 killed strains of Eschericia coli and other germs that frequently cause urinary infections.
The vaccine prompts the body to attack the bacteria on the surface of the vagina, where they live and enter the urinary tract.
Hopkins and his colleagues studied 54 women with recurrent infections. Half received the vaccine for six months and half received a placebo.
Hopkins reported last week at the Chicago Interscience Conference on Antimicrobial Agents and Chemotherapy that half of the women who got the vaccine had no new infections during the period, compared with only 20% of those who received the placebo.
Adult Sickle Cell Drug Also Helps Children
A drug useful for treating sickle cell disease in adults also works in children, according to a new study.
Most drugs used primarily in adults are assumed to have similar benefits in children, but most have not been tested in that group.
Dr. Russell Ware and his colleagues at Duke University reported in the December Journal of Pediatrics that use of hydroxyurea in children ages 6 to 24 months resulted in improved blood counts, had minimal side effects, and might delay organ damage caused by the disease. It also reduced pain during sickle crises.
Antibiotic May Reduce Severity of MS Attacks
A common antibiotic may have potential as a treatment for multiple sclerosis, according to a German-American team.
The researchers reported in the Dec. 21 Annals of Neurology that administering minocycline to rats with an autoimmune disorder closely related to MS significantly reduced the severity of disease attacks and often blocked the onset of relapses.
The group hopes to begin clinical trials in humans in 2002.
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Medical writer Thomas H. Maugh II can be reached at thomas.maugh@latimes.com.
