Science briefs: Reheads at higher melanoma risk?
- November 3, 2012 - 4:35 PM
REDHEADS MAY BE AT HIGHER MELANOMA RISK
Doctors have long urged people with red hair and fair skin to avoid the sun's ultraviolet rays. Now, a study suggests that those with ginger hair and fair complexions face an elevated risk of the disease -- even when covered up. The study, published online in the journal Nature, suggests that pheomelanin -- the reddish-yellow pigment that gives rise to rusty locks and an inability to tan -- is itself a potential trigger in the development of melanoma, the deadliest form of skin cancer. Researchers discovered that redheaded mice showed almost three times as much damage due to oxidative stress than darker haired mice, leading authors to conclude that pheomelanin itself was the culprit. Evolutionary biologists say that humans evolved fair skin as they migrated to high northern latitudes, where light was less abundant in winter. By having more pheomelanin, fairer-skinned humans were better able to synthesize vitamin D, a process that's activated by sunlight. This function is so important that the trait survived despite the increased cancer risk that comes with it.
LOS ANGELES TIMES
SECOND ILLNESS EMERGING IN MENINGITIS CASES FROM TAINTED STEROIDS
Some people recovering from meningitis in a national outbreak caused by a contaminated steroid drug have been struck by a second illness. The new problem, called an epidural abscess, is an infection near the spine at the site where the drug -- contaminated by a fungus -- was injected to treat back or neck pain. The abscesses are a localized infection, different from meningitis, which affects the membranes covering the brain and spinal cord. But in some cases, an untreated abscess can cause meningitis.
The problem has just begun to emerge, so far mostly in Michigan, which has had more people sickened by the drug -- 112 out of 404 nationwide -- than any other state. "We don't have a good handle on how many people are coming back," said Dr. Tom Chiller, the deputy chief of the mycotic diseases branch of the Centers for Disease Control and Prevention. Experts said they were especially puzzled that the infections could occur even though patients were taking drugs that, at least in tests, appeared to work against the fungus causing the infection, a type of black mold called Exserohilum.
The main symptom is severe pain near the injection site. But the abscesses are internal, so it takes an MRI scan to make the diagnosis. Some patients have more than one abscess. In some cases, the infection can be drained by a neurosurgeon. But sometimes fungal strands and abnormal tissue are wrapped around nerves and cannot be surgically removed, said Dr. Carol A. Kauffman. In such cases, all doctors can do is give a combination of antifungal drugs and hope for the best.
NEW YORK TIMES
© 2014 Star Tribune