Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:
AIDS Cases On the Rise in U.S.
The number of new AIDS cases appears to have begun rising again in the United States for the first time in a decade, federal estimates say.
The number of Americans diagnosed with AIDS increased 2.2 percent in 2002, the first time the incidence of the disease has risen since 1993, according to preliminary data from the federal Centers for Disease Control and Prevention in Atlanta.
The increase could mark a disturbing turning point in the AIDS epidemic in the United States, which had appeared to be stabilizing because of decades of intensive safe sex campaigns and the introduction of powerful new anti-viral drugs, the Washington Post reports.
The overall increase may be driven by a rise in new infections of HIV, the virus that causes AIDS, among gay men. "Our biggest concern is what appears to be a resurgent epidemic in gay men," Harold Jaffe, director of the CDC's National Center for HIV, STD and TB Prevention, told the Post.
Data from 25 states show the number of new HIV diagnoses among gay and bisexual men increased 7.1 percent from 2001 to 2002, marking the third consecutive year that infections have risen in that high-risk group. HIV diagnoses among gay and bisexual men have increased by 17.7 percent since they hit an all-time low in 1999.
On the positive side, the number of deaths from AIDS continued to decline in 2002, dropping 5.9 percent, says Jaffe, who presented the new data Monday at the National HIV Prevention Conference in Atlanta.
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Chemical That Influences Nerve Growth Found
Johns Hopkins University scientists in Baltimore have identified a chemical that can influence the growth of nerve cells, which eventually may allow doctors to repair damaged spinal cords and other nerve tissue.
The substance, semaphorin-7a, appears to encourage nerve cells to grow in a particular direction -- toward where the chemical is applied. Spinal cord injury patients often lose permanent function because any nerve cells that the body regenerates don't grow between severed or diseased pieces of the spinal cord, reports BBC News Online.
Lead author Prof. Alex Kolodkin cautions that the research is preliminary, and that doctors have to figure out how to harness the chemical's power to influence nerve growth without causing undesirable growth elsewhere.
Results of the study are published in the journal Nature.
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Land O' Lakes Recalls Contaminated Butter
Land O' Lakes says it's recalling certain lots of salted stick butter in one-pound packages that may be contaminated with small fragments of metal. No injuries have been reported.
The product was distributed in: Alabama, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Michigan, Minnesota, Missouri, Mississippi, Montana, Nebraska, North Carolina, North Dakota, Oklahoma, South Carolina, South Dakota, Tennessee, Texas, Wisconsin and Wyoming.
The butter -- sold in grocery stores between June 11 and July 26 -- has one of the following production codes listed after the date, which is located above the "nutrition facts" information on the packaging:
(date) KE 107P
(date) KE 108P
(date) KE 109P
No other Land O' Lakes products are affected. You can return any of the recalled product to the place of purchase for a full refund.
For more information, call the Land
O' Lakes toll-free hotline at 1-800-328-4155.
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Two in Florida Develop Malaria
South Florida is reporting its first cases of malaria since 1996, reports the Sun-Sentinel newspaper.
The mosquito-borne disease has been confirmed in two men in a Palm Beach County neighborhood west of Lake Worth. Both were at a July 4 neighborhood block party, where they may have been bitten by the same mosquito or one of several infected insects, state health department officials speculate. Both became ill within days of each other.
Neither infected man is believed to have traveled outside the country in the last year, so officials are busy investigating a possible source or carrier, the newspaper reports. A third person hospitalized with symptoms of the disease may also be infected, the report adds.
Symptoms of malaria include headache, vomiting, chills, fever and chattering teeth. The strain affecting the South Florida men is believed to be mild.
It is possible, but considered highly unlikely, that the illness originated in the United States. Of the 1,092 U.S. malaria cases in 2002, all but one came from abroad, according to the Centers for Disease Control and Prevention.
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Addictive Nicotine Levels in Cigarettes Vary Sharply: Study
Some cigarette brands contain up to 20 times more of the most addictive form of nicotine than other brands, according to a new report.
A study by Oregon Health and Science University found a wide range of concentrations of "free-base" nicotine in 11 popular brands of American cigarettes, according to a CBC report. Free-base nicotine is missing a hydrogen ion, which allows it to vaporize easily into a gas during smoking.
Lead researcher James Pankow says the study, which is published in the journal Chemical Research in Toxicology, is a major step in understanding nicotine addiction. "Gaseous nicotine is known to deposit super-quickly in the lungs. From there, it's transported rapidly to the brain," Pankow says. "[A] drug becomes more addictive when it is delivered to the brain more rapidly."
The researchers compared the first three puffs of smoke from each brand to measure what percentage of the nicotine is in the free-base form. They found some brands had only 1 percent free-base nicotine and others up to 36 percent.
Marlboro contained up to 9.6 percent freebase nicotine. Camel had 2.7 percent; Winston 5 percent to 6.2 percent; Gauloises Blondes, 5.7 percent to 7.5 percent. In many cases, the freebase content was higher in the first puffs. Marlboro had a freebase nicotine level of 9.6 percent in the first three puffs and 2.7 percent in later puffs, according to news wire reports.
