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Findings from a new study confirm that tea extracts applied to the skin promote the repair of damage from radiotherapy, and shed light on the mechanisms involved in the injury...
Scientists have long sought to learn whether and how stress can lead to skin problems. A new study in mice shows that a stress-triggered hormone could worsen or even cause skin disorders like psoriasis and eczema.
The scientists found that blocking the hormone called glucocorticoid—which increases in stressful times—resulted in better skin.
Understanding how glucocorticoids work could help scientists come up with ways to prevent human skin problems triggered by psychological stress, said lead researcher Kenneth Feingold of the Veterans Affairs Medical Center, San Francisco and the University of California at San Francisco.
"Here you have things going on in your mind that affect what's going on in your skin," Feingold told LiveScience.
The outermost layer of your skin, the epidermis, is composed of dead skin cells, which form a permeability barrier to prevent water loss. Every day tens of thousands of these dead cells slough off as tiny flakes. Typically, cells at the bottom of the epidermis grow, move to the surface and differentiate into skin cells to replace the lost flakes.
Previous research showed that psychological stress decreases cell growth and inhibits differentiation into skin cells.
In the new study, scientists subjected hairless mice to stress while either blocking the production of glucocorticoids or blocking the action of the hormone. Some mice weren't treated at all. The stress was created by placing the mice in small cages in constant light with a radio playing for 48 hours.
The two groups of mice treated with a type of glucocorticoid-blocker showed much better skin function compared with untreated and stressed mice.
While the researchers hope the study will lead to a way to treat people who suffer these skin conditions, there is still a long way to go. Besides needing to test the effect in people, blocking glucocorticoids could have negative side effects that are worse than exacerbations of skin disorders.
The research is detailed in the December issue of the American Journal of Physiology-Regulatory, Integrative and Comparative Physiology.
By Jeanna Bryner, LiveScience Staff Writer, December 7, 2006
By: Kirsten Sheridan
Discover the importance of a balanced internal and external pH in slowing the aging process.
Personal misuse of super-strength botulinum toxin caused a Florida osteopath, his girlfriend, and two of his patients to become paralyzed and hospitalized for months in 2004.
Details of the much-publicized incident—which ended in the practitioner being sentenced to three years in prison—are only now published in this week's issue of the Journal of the American Medical Association.
At the time of the incident, Bach McComb was an osteopathic physician who was continuing to practice in Oakland Park, Fla., after his license had been suspended. In the four cases described, McComb did not use a medical version of Allergan Inc.'s Botox.
Instead, he mistakenly gave himself and the three others four to six injections of a preparation of paralyzing botulinum toxin that was 2,800 times stronger than that typically used on patients, according to the authors of the JAMA article. This formulation was only intended for laboratory work.
The vial's labeling clearly marked the product as not being suitable for human use.
"The fact that clinical practitioners were using an unlicensed product was very disturbing," said Dr. Christopher R. Braden, a medical epidemiologist at the U.S. Centers for Disease Control and Prevention, and an author of the report. "It needed to be highlighted and the issue dealt with so that it does not recur."
"A 100-microgram vial of toxin taken from the same manufacturer's lot as the toxin administered to the case patients contained a toxin amount sufficient to kill approximately 14,286 adults if disseminated evenly," according to the JAMA report.
McComb, his two patients, Eric and Bonnie Kaplan, and McComb's girlfriend, Alma Hall, were each paralyzed by the time they were admitted to a hospital.
All of the patients eventually survived but were hospitalized for months and required assistance for basic functions such as breathing, speaking and walking. McComb was later sent to prison for three years.
The incident does not reflect on the safety of standard treatments of Botox, stressed Dr. John Canady, a professor of plastic surgery at the University of Iowa and vice president of the American Academy of Plastic Surgeons.
"This was clearly not Botox," Canady said. "More than 3 million people got Botox injections in 2005, which is the last year we have statistics on, and I don't believe any reaction such as this has been reported."
The real Botox is carefully packaged by its manufacturer, Allergan, Canady explained. "Botox comes in a vial that does not have an excessive dose, and it is reconstituted in the same vial," he said. "None of these safeguards were in place" in the Florida case, Canady added.
Basic precautions against such misuse are obvious, Canady said.
"It is important to go to a board-certified plastic surgeon," he said. "You should feel free to ask that person what his track record has been in the use of Botox. Probably the biggest take-home message is that it is important to do your homework before any medical procedure, and that includes Botox."
In addition, "It's absolutely fair to ask what material is being injected into you personally," Canady said. "I don't think it's too much to ask to see the container or the material."
And Braden cautioned consumers about bargain-hunting.
The last time he looked at the Internet, he saw advertisements for "Botox-like" medications. "I would be very suspect of those kinds of products," Braden said.
By Ed Edelson, HealthDay Reporter, November 21, 2006
Marathon runners can be proud of their stamina, but all that time outdoors boosts their risk of skin cancer, including the potentially deadly malignant melanoma, according to a study in the Archives of Dermatology.
"We are the first to report this," researcher Christina M. Ambros-Rudolph, MD, tells WebMD in an e-mail interview.
Ambros-Rudolph is a consultant dermatologist at the Medical University of Graz, Austria.
She and her co-researchers, all runners, conducted the study after caring for eight ultra-marathon runners with malignant melanoma over the past decade.
Comparing Runners and Nonrunners
In the study, the researchers evaluated 210 marathon runners, men and women, aged 19 to 71.
They compared the runners' skin cancer risks with those of 210 men and women matched for age and gender who were not long-distance runners.
All participants underwent a skin cancer exam and answered questions about personal and family skin cancer history, as well as changes in skin lesions, sunburn history, sun sensitivity, and physical characteristics such as skin and eye color.
Even though more of the nonrunners had higher sun sensitivity, reflected by their light eyes and sensitive skin types, the runners had more atypical moles and more lesions called solar lentigines—often called "liver spots"—which are associated with a higher risk of malignant melanoma.
Not surprisingly, the more intense the training regimen, the more likely a marathon runner was to have the lesions and moles, Ambros-Rudolph found. While some runners logged about 25 miles a week, others put in more than 44 miles a week.
No lesions suggestive of malignant melanoma were found, but 24 marathoners and 14 from the control group were referred to dermatologists to evaluate growths that looked like nonmelanoma skin cancers (such as basal cell and squamous cell skin cancers).
What's behind the increased risk?
The study reflects what dermatologists see in practice, says Diane Madfes, MD, a New York City dermatologist and a spokeswoman for the Skin Cancer Foundation.
Among her patients who are long-distance runners, Madfes says she has seen many cases of abnormal moles as well as nonmelanoma cancers, though not much melanoma, she says.
Greater ultraviolet exposure, of course, is one explanation for the increased risk, say the Austrian researchers.
Nearly 97% of the runners studied said they wore running shorts and short-sleeved or sleeveless shirts.
Only 56% said they regularly use sunscreen; nearly 2% never do.
Also, long-term, high-intensity exercise suppresses the immune system, the Austrian researchers write. They note that patients who have undergone transplants and had immunosuppressive therapy have an increase in all types of skin cancers.
Reducing the Risk
Ambros-Rudolph advises runners to cover up, train when sunlight exposure is less intense, and slather on the sunscreen—in spray or lotion form. An SPF of 15 or higher is recommended.
The type of product preferred varies by gender, Ambros-Rudolph has observed. "Men usually hate using lotions, and sprays are quicker to apply and easier to apply on hairy skin, while women often suffer from dry skin and love lotions that moisturize at the same time."
Reapplying a water-resistant sunscreen every two hours is important, adds Madfes.
She suggests runners consider bicycling attire, especially the long-sleeved shirts made of newer wicking materials that draw away moisture from sweat.
About 62,000 new cases of malignant melanoma are expected this year in the U.S., along with more than a million nonmelanoma skin cancers, says the American Cancer Society.
About 8,000 are expected to die this year from malignant melanoma; nonmelanoma skin cancers will claim about 2,000 lives.
By Kathleen Doheny, WebMD Medical News, November 20, 2006
The Australian government has launched an advertising campaign aimed at raising awareness among teenagers of the dangers of skin cancer.
A graphic series of TV ads shows that overexposure to the sun can cause skin cancer in people of all ages.
Australia's chief medical officer, John Horvath, told the Australian Broadcasting Corporation many teenagers are unaware of the facts about skin cancer and they are too young to remember earlier public education campaigns.
"You have to get the message out there again and dispel some of the myths that, 'if you don't get sunburned you'll be all right,' or that a suntan or an olive skin protects you. None of those things are true," Horvath said.
United Press International, November 19, 2006
Finally, there may be something duct tape can't fix: the lowly wart.
Despite claims in an earlier study, covering warts with duct tape may not make them vanish faster after all, say Dutch researchers, including Maastricht University's Marloes de Haen, MD.
The Dutch researchers had heard of a study in which duct tape showed promise as a home remedy for warts -- the skin infections caused by the human papillomavirus.
So de Haen's team conducted their own study, now published in the Archives of Pediatrics & Adolescent Medicine.
The study included 103 Dutch kids aged 4-12 who had at least one wart.
For six weeks, half the children wore duct tape over one of their warts, while the rest wore corn pads over one of theirs.
Once a week, the children uncovered the wart, soaked it in warm water for five minutes, then rubbed the wart gently with a pumice stone.
During the study, the warts covered by duct tape were only slightly more likely to heal than those covered by corn pads.
"After six weeks, the wart had disappeared in 16% of the children in the duct tape group, compared with 6% in the placebo [corn pad] group," the researchers write.
That margin was so slim that it may have been due to chance, de Haen's team says.
Most of the kids in the duct tape group -- 81% -- said the tape didn't stick well to their skin. And 15% reported skin irritations, including rashesrashes.
"Further research with longer follow-up would only be useful with a tape that is better sticking," write the researchers.
By Miranda Hitti, WebMD Medical News, November 8, 2006
Plagued by poison ivy allergy? It might be possible to coax the body to build up immunity to poison ivy.
That news comes from researchers including Mary Morris, MD, of Allergy Associates of La Crosse in La Crosse, Wis.
They studied 115 people with a history of severe skin reactions to poison ivy who were treated at their clinic over the past 15 years.
The treatment was a small amount of poison ivy extract placed under the tongue. The goal was to train the body's immune system not to overreact to poison ivy.
The patients took skin tests to see if the treatment helped.
Those tests showed that after treatment, patients had a much higher threshold for allergic skin reactions to poison ivy.
Ninety percent of the patients said they had "far fewer" skin reaction episodes. Patients who said they still got skin rashesrashes reported milder rashes that were quicker to heal than before treatment.
Further tests are needed. If those tests go well, the treatment may help people whose jobs and hobbies expose them to poison ivy, the researchers note.
The findings were presented in Philadelphia at the American College of Allergy, Asthma, and Immunology's annual scientific meeting.
By Miranda Hitti, WebMD Medical News, November 14, 2006
The Abbott Laboratories drug Humira (adalimumab) has been given expanded approval by the U.S. Food and Drug Administration to slow structural joint damage in people with psoriatic arthritis. The condition affects people who have skin psoriasis.
Humira was initially approved for overall treatment of psoriatic arthritis in October 2005. It's also been sanctioned to treat moderate-to-severe rheumatoid arthritis, and an inflammatory disease of the spine called ankylosing spondylitis.
Psoriatic arthritis combines symptoms of arthritis—including joint pain and inflammation—with those of psoriasis, including painful red lesions on the skin. Clinical testing on 313 people who hadn't responded to NSAID therapy found that people given Humira had significantly less joint damage than study participants who took a non-medicinal placebo, Abbott said in a statement.
People who took Humira also demonstrated increased ability to perform daily functions such as getting dressed, walking, and climbing stairs, the company said.
HealthDay News, November 14, 2006
The bumps (papules) and pimples (pustules) of rosacea, a poorly-understood facial disorder affecting an estimated 14 million Americans, may be the result of an allergy-like reaction to environmental and emotional triggers, according to new study results presented at the National Rosacea Society (NRS) research workshop during the annual meeting of the Society for Investigative Dermatology and reported in Rosacea Review.
"We are very excited about these findings because they may provide the basis for improving the treatment and management of this condition," said Dr. Richard Gallo, chief of the division of dermatology at the University of California-San Diego and lead investigator of the NRS-funded study. "By defining the process leading to the inflammation, new medications might be developed to block these effects."
Dr. Gallo explained that when the normal immune system is faced with any of a broad range of potential dangers—such as sun exposure, emotional stress, heat and spicy foods, among many others—receptors recognize potential threats and protect the body by prompting the production of protective substances that isolate and neutralize any harmful effects. With rosacea, however, these protective substances turn the body on itself like overzealous guards, leading to inflammation.
Using advanced mass spectrometry technology to analyze the biochemical composition of proteins in rosacea patients, the researchers discovered an abnormality in the production of protective molecules known as cathelicidins, Dr. Gallo said. In normal patients, the cathelicidins are found in a form that is inactive and would not lead to bumps and pimples. In rosacea patients, the forms of cathelicidins are different and lead to skin inflammation. The cause of this abnormality in cathelicidins seems to be due to an equally important problem in rosacea—an overabundance of yet another substance, called kallikrein, which can spur dormant cathelicidins into action.
"It appears that the combination of these two substances at abnormally high levels is a double whammy for rosacea patients," Dr. Gallo noted.
The researchers recently completed the picture when they were able to demonstrate that this process is linked to the actual formation of rosacea signs and symptoms. The skin of mice injected with the cathelicidins found in rosacea patients showed a dramatic inflammatory response—including bumps and pimples—while mice injected with normal cathelicidins showed no inflammation, either visually or under a microscope.
"The next step is to test these findings in human subjects through various therapeutic interventions," Dr. Gallo said. "As we gain a thorough understanding in humans, we can look for new medications that block this process in order to treat or prevent the inflammation associated with rosacea."
Rosacea is a chronic disorder that primarily affects the cheeks, nose, chin or forehead, and is often characterized by flare-ups and remissions. It typically begins as a flushing or redness that comes and goes, and visible blood vessels may also appear. Inflammatory bumps and pimples often develop, and in severe cases, the nose may become swollen and enlarged from excess tissue.
In addition to long-term medical therapy to bring the condition under control and maintain remission, patients are advised to keep a diary to identify and avoid lifestyle and environmental factors that may affect their individual cases. Some of the most common rosacea triggers include sun exposure, emotional stress, hot or cold weather, wind, heavy exercise, alcohol, hot baths and spicy foods.