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New in Physiology (page 61 of 72)
Research is shedding new light on sunscreens that might someday prevent or treat skin cancer by reversing dangerous gene mutations caused by overexposure to the sun.
The Journal of Cosmetic Dermatology has published a report claiming that topically applied caffeine is a succesful slimming agent.
Women seeking an acne medicine that can cause severe birth defects may find it a little easier to fill their prescription: The government announced some changes Wednesday designed to ease access to the troublesome drug.
A program called iPledge was designed to ensure that every user of Accutane or its generic competitors—and every doctor who prescribes it and every pharmacy that sells it—follows strict rules to make sure that women don't get pregnant while on the drug. Among those rules are month-by-month prescriptions based on passing pregnancy tests.
But last summer, the Food and Drug Administration heard evidence that iPledge hasn't ended the problem: There were 122 pregnancies in the program's first year and another 37 in the four months since. Another 19 pregnancies occurred in women who managed to get the drug despite never enrolling in iPledge.
Still, in October the FDA agreed to a few changes to the program, and announced Wednesday that iPledge is now implementing these changes:
* Women of childbearing age who don't fill a prescription within seven days of a pregnancy test will be allowed to get another test and then fill the prescription—with the exception of the initial prescription. Until now, those who didn't act within seven days were frozen out of the program for the next 23 days.
* Those women will have to fill the prescription within seven days of a pregnancy test rather than within seven days of first seeing their doctor.
Associated Press, December 5, 2007
Researchers at the Stanford University School of Medicine have reversed the effects of aging on the skin of mice.
Researchers have identified a batch of genes that not only prevent cancer but slow the aging process in worms, and say they are now looking to see if the genes have the same properties in humans.
Many of the genes in the worms are already known to have counterparts in humans, and the team at the University of California, San Francisco, say they hope to better understand some of the processes that cause both aging and cancer. Drugs that mimic the effects of these genes might help people both avoid cancer and also live longer, they wrote in an issue of the journal Nature Genetics.
Biologist Cynthia Kenyon is perhaps best known for discovering that a change in just one gene, called daf-2, could double the life span of small roundworms called Caenorhabditis elegans.
She and graduate student Julie Pinkston-Gosse screened as many genes as they could that were affected by daf-2. They looked at 734 in total, and found that 29 of them either stimulated tumor growth or suppressed it. Some caused cell proliferation—which goes haywire to help a tumor grow and spread—while others initiated a programmed suicide process called apoptosis, used by the body to destroy faulty cells, including tumor cells.
"About half of these genes also affected normal aging, thereby linking these two processes mechanistically," the two researchers wrote.
"There is a widely held view that any mechanism that slows aging would probably stimulate tumor growth," Kenyon said in a statement. "But we found many genes that increase life span, but slow tumor growth. Humans have versions of many of these genes, so this work may lead to treatments that keep us youthful and cancer-free much longer than normal."
The genes that stimulated tumor growth also accelerated aging, Kenyon found. The genes that prevented tumor growth slowed down the aging process and extended life span in the worms.
Kenyon said the findings strengthen theories that the controls of life span and cancer have deep, common roots.
Small creatures that researchers work on, such as the C. elegans roundworm, often share genes with humans, and these genes often underlie key biological processes.
Reuters, October 15, 2007
The changing of the season brings cooler weather, shorter days and more people heading to health clubs for a healthy dose of indoor exercise. While experts agree that exercise is one of the most beneficial activities a person can do to improve one’s overall health, dermatologists want gym-goers to be aware of the hidden dangers of exercise–bothersome skin conditions that can be painful and inhibit further physical activity if left untreated.
In recognition of National Healthy Skin Month, dermatologist Brian B. Adams, MD, MPH, FAAD, associate professor of dermatology at the University of Cincinnati and director of dermatology at the Veterans Administration Medical Center, both in Cincinnati, Ohio, spoke at the American Academy of Dermatology’s (Academy) SKIN Academy on the most common skin conditions to which people who engage in regular indoor exercise are susceptible and how to treat them.
“Despite its positive effect on a person’s physical and psychological health, regular exercise does not necessarily improve our skin health and may in fact lead to a rash of skin conditions that require treatment,” said Adams. “While exercising indoors eliminates the threat of skin cancer and sun damage, it is important for people who frequent health clubs to be aware of the risks to their skin as well.”
Blisters form when friction between an area of the body and athletic equipment causes a splitting of the top layer of skin, allowing fluid build-up. Runners and those who routinely lift weights often develop blisters. Adams suggests that the key to preventing blisters is to reduce friction by creating more distance from the equipment to the skin.
“Wearing moisture-wicking socks, applying a thin layer of petroleum jelly between the sock and the shoe, and using gloves to lift weights can help prevent blisters from forming,” said Adams. “Also, there is no better dressing for blisters than your own skin, so you should not peel off the top layer of a blister. If it comes off, keep the blister covered with petroleum jelly and a bandage.”
While blisters normally do not become infected, Adams cautioned that redness appearing on the skin in the vicinity of the blister could indicate an infection and should be treated by a dermatologist.
Unfortunately, health clubs are breeding grounds for all kinds of fungus–from swimming pool floors and diving boards to showers and locker rooms. The most common contagious fungal infection that exercise enthusiasts are prone to developing is tinea pedis, or athlete’s foot. This fungus grows best in dark, moist and warm environments, making sweaty feet tucked inside running shoes perfect targets.
Perhaps the most bothersome symptom of athlete’s foot is the itching and burning sensation people feel on their feet. In some individuals, the skin between the toes peels, cracks and scales, while others may experience redness, scaling or dryness on the soles and along the sides of the feet. Some people who develop athlete’s foot also may be at risk for toenail fungus, which can be difficult to treat without dermatologic care.
“The best defense against athlete’s foot is to never go barefoot in a health club,” advised Adams. “Wear shoes, socks, sandals or aquatic shoes at all times.”
Adams added that most cases of athlete’s foot respond well to over-the-counter medications, but persistent or recurring infections will require prescription-strength medications from a dermatologist.
Regular exercisers also may be susceptible to acne mechanica, a form of acne that can occur under athletic equipment or tight-fitting clothing. Acne mechanica typically develops in warm, moist environments–especially areas prone to friction. Wearing tight-fitting exercise shorts made of non-breathable fabrics can even cause an acne flare-up on the buttocks.
“Changing your workout attire by eliminating tight-fighting clothing and adding more breathable, moisture-wicking fabrics can help prevent acne mechanica,” said Adams. “If these preventive measures are not working, your dermatologist can prescribe prescription medications that are effective in treating this type of acne.”
Originally termed for outdoor athletes, turf burns (or road rash) are nasty abrasions that can occur on an area of the body–usually the arms or legs–if athletic padding is not used. Most cases of indoor turf burns are caused by sliding on the basketball court or from constant contact with exercise mats or carpet.
“For the quickest healing and to avoid scarring, turf burns need to be cleaned and covered with petroleum jelly and a bandage,” said Adams. “If there are any signs of an infection or it doesn’t seem to be healing properly, see your dermatologist.”
Indoor Tanning: Take a Pass
Unfortunately, not everything in a health club is “healthy.” Perhaps the biggest health threat is indoor tanning devices, which are still offered at some health clubs across the country despite their link to skin cancer. Ultraviolet light, whether from natural sunlight or artificial light sources, increases a person’s risk of developing skin cancer.
In September 2007, President Bush signed the Tanning Accountability and Notification Act (TAN Act) into law, which calls for the U.S. Food and Drug Administration to determine if the current language and positioning of warning labels on indoor tanning devices is adequate to effectively warn consumers of the known dangers of indoor tanning–including the risk of skin cancer.
“As dermatologists, we see the serious health consequences skin cancer poses for patients every day,” said Adams. “There is absolutely nothing healthy about indoor tanning that should allow it to be offered to health club patrons, who are in some cases being misled to think that this form of UV-exposure is safe and that a tan is somehow healthy. Hopefully this new law will force health clubs to re-examine their choice about offering a disservice like indoor tanning to their patrons.”
In addition, Adams offered these sun-safety tips for outdoor fitness buffs:
* If possible, seek shade between 10 a.m. and 4 p.m. when UV rays are the strongest.
* Runners and those engaging in other outdoor sports should wear broad-spectrum sunscreen with an SPF of 15 or higher and reapply frequently when sweating. Stash sunscreen in your pockets as a reminder to reapply and wear dark-colored clothing which has built-in SPF, if possible. Hats should always be worn, and men should never run with their shirts off.
* Skiers should be aware that snow is 80% reflective, even in shaded areas, and skiers are more likely to burn at higher altitudes.
* “Being aware of the skin problems that can arise from indoor or outdoor exercise is a crucial first step in keeping your skin healthy and getting the most out of your workouts,” said Adams. “If you have a concern about your skin, whether or not it’s related to exercise, it’s important to see a dermatologist for diagnosis and treatment.”
Researchers now believe they have found a key mechanism that drives rosacea.
Experts now believe that a lifetime of overeating sugar can make skin dull and wrinkled.
A team at Procter & Gamble Beauty sequenced the genome of Malassezia globosa, a fungus that grows on the skin of between 50-90% of the population.
Scientists have discovered that an extract of broccoli sprouts protects the skin against the sun's harmful ultraviolet rays.