The Big Brushoff: Latest Plaque Fighter Passes Test
Triclosan, a popular germ-killer used in deodorants and soaps for decades, was added to toothpaste three years ago. A new technology enabled the antimicrobial to stick to teeth and gums for hours, killing the microbes that thrive in plaque. After two clinical trials and safety studies, the Food and Drug Administration granted Colgate, which holds the patent for the technology, the right to claim that its triclosan-containing Total Toothpaste worked against gingivitis. Now the powerful ingredient has been tested as the latest thing in toothbrushing, a liquid tooth cleaner. The results are published in the current issue of the Journal of the American Dental Assn.
A study of 124 men and women who had at least moderate plaque buildup showed that the triclosan-fortified liquid reduced plaque three times more effectively than the placebo liquid. Co-author Dr. Martin Giniger, director of diagnostic sciences at the New Jersey Dental School in Newark, said that after six months, triclosan diminished gingivitis, the earliest form of gum disease, twice as well as the placebo.
Liquid tooth cleansers have been available in Europe since 1994, but have only recently debuted in the U.S. Crest, Rembrandt and Colgate have liquids--sometimes called liquid gels--on drugstore shelves now. No triclosan-containing liquid has yet been evaluated by the American Dental Assn., and no such product has reached the market in the United States.
Antidepressant Studied as Hot-Flash Treatment Without Hormones
Hormone replacement therapy relieves hot flashes in most menopausal women, but those who can’t take estrogen have to put up with the troublesome and embarrassing symptom. A solution for them may be the antidepressant venlafaxine (Effexor).
A four-week study of 221 women showed that venlafaxine reduced the frequency of hot flashes in the treated group by as much as 60%, depending on the dosage. Those flashes that did occur were less severe as well. All the women either had been treated for breast cancer or thought they were at high risk of the disease and so did not want to undergo the therapy. To see if the benefit of the antidepressant would last and what dose worked best, the Mayo Clinic researchers continued to follow 102 of the women taking the non-hormonal treatment for another eight weeks.
The results of this study were recently published in Oncology Nursing Forum, a medical journal. The researchers found that the hot flashes continued to decrease in frequency and severity during the two-month study period. And, says investigator Charles Loprinzi, a Mayo Clinic oncologist, “The women got significant relief from half the dose that is usually given to treat depression.” The advantage of that low dose is fewer side effects.
Late-Night Snacking Might Be Prompted by Hormonal Imbalance
Habitual midnight snacking may signal a stressed-out hormone system more than a stress-filled life. Night eating, scientists are beginning to think, isn’t about hunger, but more likely the result of a hormonal imbalance. Norwegian researcher Grethe Birketvedt and her colleagues have studied a group of five people who eat more than half their daily calories after bedtime and found that the night eaters all have a weak hormonal response to stress.
Birketvedt reports in the American Journal of Physiology: Endocrinology and Metabolism that the hormones produced by two glands that regulate sleeping and eating, and a third that releases cortisol, a stress hormone, may be slightly off-kilter in the night eaters, compared to healthy study participants. Birketvedt explains that the interplay of these off-balance chemical messengers causes biological confusion. The person tends to wake up in the middle of the night instead of sleeping through. And, sure enough, the appetite clicks in then too.
It’s not known what causes a weakness in the trio of glands known as the HPA axis (for hypothalamic-pituitary-adrenal axis), but there may be a genetic connection. “Night eating does run in families,” says Birketvedt, a researcher at the Institute of Clinical Medicine at the University of Tromso in Norway. Disturbances in the HPA axis also have been linked to fatigue syndrome, anorexia and depression.
New Vaccine Shows Promise as a Way to Ward Off Staph Infections
Some unfortunate people with weakened immunity become even sicker in the hospital. They cannot resist infection by the potentially deadly staph organism, and the invading bacteria multiply unimpeded in their blood. From the bloodstream, the bacteria may travel to the bones, the lining of the heart, the lungs and other internal organs. Staph infection is the 13th leading cause of death in hospitalized patients. Making the threat even worse is the increasing resistance of the bacteria to antibiotics.
The solution may be a vaccine that recognizes the coating on the bacteria, alerts the body to the danger and stimulates the production of antibodies to destroy the bacteria. The first vaccine to do this was tested in 892 very sick patients undergoing kidney dialysis at 73 centers, mostly in California. A control group of 906 patients received a placebo injection of saline.
One shot of StaphVAX cut the number of infections by nearly 60%, and immunity lasted about 10 months. During the course of the yearlong study, 86% of those tested had a high level of staph-killing antibodies in their blood. Next year, Nabi, the biotechnology firm that developed the vaccine, will begin final testing to confirm these results.
Day-Care Toddlers’ Frequent Colds Lead to Benefit Later, Researchers Say
Doctors often like to reassure parents that the frequent colds that plague toddlers in day care will give the children immunity to bugs when they get older. The problem is that the common-sense assertion has never been proven. Studies have yielded conflicting results. Now, the first long-term study of nearly 1,000 children finally gives firm scientific credence to the adage that a cold is an educational experience for a child’s immune system.
University of Arizona researchers report in the Archives of Pediatric and Adolescent Medicine that toddlers in large day-care centers had twice as many colds as those cared for at home. The payoff was that between ages 6 and 11, the kids from large day-care centers had the fewest colds. During grade school years, stay-at-home children and those who attended centers caring for fewer than five children had colds with about the same frequency. By age 13, the protective effect of early bouts with cold viruses disappeared, and all children had about the same number of infections. But by then, at least, a cold for the child doesn’t always mean a sick day for a parent.
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Dianne Partie Lange can be reached by e-mail at DianneLange@cs.com.
