Most Popular in:

Skin Science

New in Skin Science (page 89 of 92)Sign up for this RSS Feed!

Oct
03
2006

Drug-resistant Acne Runs in the Family

An antibiotic-resistant acne germ can spread among family members, Swedish researchers find.

The germ is Propionibacterium acnes. Skin colonized by P. acnes tends to erupt into the blotches and pustules of acne. Since the 1960s, doctors have fought P. acnes with antibiotics. The bug fought back. It's now common to find P. acnes strains resistant to several common antibiotics.

Doctors hoped that the only people carrying the drug-resistant acne bugs would be patients on long-term antibiotic therapy. That isn't the case, find Carl Eric Nord, MD, PhD, and colleagues at Karolinska Institute in Stockholm, Sweden.

Nord and colleagues took skin samples from 10 acne patients, all on antibiotic therapy, and from two close family contacts of each patient. Twelve healthy, acne-free volunteers -- who were not taking antibiotics and did not have family members with acne -- served as a comparison group.

Nord and colleagues found that nearly half of the family members carried drug-resistant acne bacteria on their skin. Genetic analysis showed that these family members carried the same strain of P. acnes as the acne patient among them.

The good news is that the family members fought off the drug-resistant germs -- but only after the acne patient in their family stopped using antibiotics.

On the other hand, you apparently can't avoid drug-resistant acne germs by avoiding people with acne. A third of the healthy comparison group also carried drug-resistant P. acnes on their skin.

Nord reported the findings at last week's 46th Interscience Conference on Antimicrobial Agents and Chemotherapy, held Sept. 27-30 in San Francisco.

SOURCES: 46th Interscience Conference on Antimicrobial Agents and Chemotherapy, San Francisco, Sept. 27-30, 2006.

By Daniel DeNoon, WebMD, October 2, 2006

Oct
02
2006

Beauty is Easy on the Brain

"Easy on the mind" rather than "easy on the eyes" may be a better way to describe something that’s beautiful, according to a new study.

Researchers found objects and animals that conform to a prototype rather than deviate from it are easier for the brain to process and, therefore, are perceived as more pleasing to the eye.

"What you like is a function of what your mind has been trained on," says researcher Piotr Winkielman of the University of California, San Diego, in a news release. "A stimulus becomes attractive if it falls into the average of what you've seen and is therefore simple for your brain to process. In our experiments, we show that we can make an arbitrary pattern likeable just by preparing the mind to recognize it quickly."

Researchers say the findings build a phenomenon known as "beauty-in-averageness effect," which was discovered in the late 1800s. The theory holds that prototypical images are rated as more beautiful or appealing than variations of the same thing.

'Beauty' Experiments

To test the theory, researchers had groups of students undergo different experiments. In one experiment, a group of students were presented prototypes of random groupings of dots. Then distortions of the dots in these prototypes were created and presented to the students.

In a second experiment, a group of students rated the attractiveness of random dot patterns and those that conformed to common geometric patterns, like a diamond or square.

The results, published in Psychological Science, showed that the participants categorized patterns quicker and rated them as more attractive when they were closer to their respective prototypes.

A third experiment had students looking at dots also, but this time also examined cheek muscle for smiling action and brow muscle for frowning action.

Researchers also found that the less time it took participants to classify a pattern, the more attractive they found it.

"This parsimonious explanation," says Winkielman, "accounts for cultural differences in beauty -- and historical differences in beauty as well -- because beauty basically depends on what you've been exposed to and what is therefore easy on your mind."

SOURCES: Winkielman, P. Psychological Science, September 2006; vol 17: pp 799-806. News release, University of California, San Diego.

By Jennifer Warner, WebMD, September 29, 2006

Sep
29
2006

Melanoma Surgery Gets Broader Scope

Melanoma surgery may get more aggressive to help plan treatment and ultimately improve survival.

A study and editorial in The New England Journal of Medicine support checking the "sentinel" lymph node near melanoma for signs of cancer.

Melanoma is the most serious type of skin cancer, with more than 53,600 new cases per year diagnosed in the U.S., according to the National Cancer Institute.

The body's lymph system makes, stores, and carries white blood cells that fight infections and other diseases. Lymph nodes are part of the lymph system; they're clustered around the body.

Cancer can spread to lymph nodes. It usually first shows up in one or two "sentinel" nodes that are closest to the cancer site.

In sentinel lymph node biopsy, doctors surgically check the sentinel lymph node or nodes for signs of cancer.

If the biopsy shows cancer in the sentinel node or nodes, that means cancer has spread beyond its original location and would be more likely to be in the other lymph nodes in the area. Sentinel node biopsies are also used with other types of cancer, including breast cancer.

Sentinel Node Study

The new study comes from researchers including Donald Morton, MD, of the John Wayne Cancer Institute at Saint John's Health Center in Santa Monica, Calif.

Morton's team studied 1,269 people who had surgery to remove isolated skin melanomas of medium thickness.

The researchers randomly assigned 60% of the patients to get sentinel node biopsy. Patients with cancerous sentinel nodes had all the other lymph nodes near the sentinel nodes removed.

The remaining 40% of the patients got careful checkups every few months, without sentinel node biopsy. They kept all of their lymph nodes unless doctors suspected cancer's spread, which happened months or even years later.

Why not just automatically remove all lymph nodes closest to a melanoma? Doing so could have complications and offers no advantage if those nodes are cancer-free.

Study's Results

The researchers followed the patients for five years.

During that time, the overall survival rate between the two groups was similar (around 87%).

But there was an important exception for patients with cancerous lymph nodes.

Of the patients who got sentinel node biopsies that showed cancerous sentinel nodes and had their nearby lymph nodes immediately removed, 72% were alive five years later.

But the five-year survival rate was much lower -- 52% -- for patients with cancerous lymph nodes that were spotted later because they didn't get sentinel lymph node biopsy.

In patients with skin melanomas of medium thickness, sentinel node biopsy "should be preferred to observation," write Morton and colleagues.

That conclusion is "convincing" and "justified," based on the study's results, write editorialists Charles Balch, MD, and Natale Cascinelli, MD.

Balch works in Baltimore, Md., at the Johns Hopkins Medical Institutions. Cascinelli works at the National Tumor Institute in Milan, Italy.

SOURCES: Morton, D. The New England Journal of Medicine, Sept. 28, 2006; vol 355: pp 1307-1317. Balch, C. The New England Journal of Medicine, Sept. 28, 2006; vol 355: pp 1370-1371. National Cancer Institute: "What You Need to Know About Melanoma."

By Mirandi Hitti, WebMD, September 27, 2006

Sep
27
2006

Compulsive Skin Picking

By Judi Bailey

Learn more about identifying this disorder and helping clients who demonstrate its symptoms.

Sep
25
2006

Key to a Safe Tan for Fair-Skinned People Discovered

Fair-skinned people who yearn for a suntan -- even though they know it's hopeless and unhealthy -- may one day have cause for celebration.

Harvard scientists have discovered new information about how the skin tans or -- in the case of fair-skinned people -- stubbornly refuses to tan due to a genetic defect. Using a skin treatment, they have turned pale skin dark, while also protecting it from ultraviolet-induced skin skin cancer.

"Darkening a person's skin may mimic the protective benefit seen in people who otherwise make a large amount of pigment," says researcher David E. Fisher, MD, PhD, director of the Melanoma Program at Dana Farber Cancer Institute in Boston. And that could translate into a reduction in the toll of the potentially deadly skin cancer melanoma, expected to be diagnosed this year in 62,000 people in the U.S. and to result in 8,000 deaths, according to American Cancer Society projections.

The study appears in the Sept. 21 edition of the journal Nature. Fisher cautions that the study was done only in animals. Using a topical cream instead of the sun's rays, Fisher's team was able to switch on the tanning mechanism in the skin cells of fair-skinned mice, turning them into olive-skinned animals. "This has not been demonstrated in people and there is a lot that needs to be proven before it's ready for even a first attempt in clinical subjects," Fisher says.

Even so, the study was called intriguing by Meenhard Herlyn, DVM, PhD, a tumor biologist at The Wistar Institute, a research center on the campus of the University of Pennsylvania. "What he clearly has shown is ... you can induce a pigmentation, tanning, and the purpose is that people who are very susceptible to skin cancer, including melanoma, can be protected."

By Kathleen Doheny, WebMD, September 20, 2006

Sep
20
2006

CTFA Files Comments With FDA on the Use of Nanotechnology in Personal Care Products

The Cosmetic, Toiletry, and Fragrance Association (CTFA) announced today that it has filed comprehensive comments with the Food and Drug Administration (FDA) on the science and regulation of nanoparticles in personal care products.  CTFA comments, which can be found at www.ctfa.org, specifically address issues raised in a petition filed with the FDA earlier this year on the use of nanotechnology in personal care products, in particular, sunscreen products.
 
“Nanoparticles in sunscreens are very small particles that have been reviewed and approved by FDA.  They have been used safely and effectively by consumers for decades to protect from harmful UV rays and to prevent skin cancer,” said John Bailey, executive vice president for science at CTFA and former FDA official.  “These ingredients have properties that provide a greater degree of protection from the sun, are transparent when applied and aesthetically pleasing, and therefore encourage greater consumer acceptance.”
 
The nanoparticles in sunscreens, titanium dioxide and zinc oxide, are established, efficacious sunscreen filters that have been on the market for decades. In 1996, FDA concluded that smaller, micronized particles of titanium dioxide are not new substances and that there is no evidence demonstrating that these micronized particles are unsafe.  Nano-sized titanium dioxide and zinc oxide, unlike the larger particle size ingredient, form a transparent rather than a thick, white coating, which leads to greater consumer acceptance and use of sunscreen products, and therefore greater protection from skin cancer and other damaging effects of the sun.  The same improvement in formulation esthetics also applies to the use of these materials in cosmetics.
 
“Nanoparticle ingredients in personal care products sit on top of the skin, are used in small amounts, and are not absorbed into the body.  The general scientific consensus is that there is no risk to human health.  But we don’t rest on this knowledge alone,” Bailey said.  “We take the science of safety very seriously, and that is why we review the latest and most comprehensive scientific research, including nanotech research, before bringing a product to market.”
         
According to widely accepted independent research studies, the size of these nanoparticles does not make them inherently different in terms of toxicity or impact on human health than larger particles. It is also important to note that humans have long been exposed to some types of nanoparticles in the atmosphere such as smoke from candles, fireplaces and other sources. 
 
In the case of the sunscreen ingredients zinc oxide and titanium dioxide, the overwhelming weight of the scientific evidence states that these substances are safe and non-toxic, including when used in cosmetics and sunscreens.  
 
 
Authoritative bodies that have thoroughly reviewed titanium dioxide and zinc oxide include:
 
-          The FDA:  
Concluded that these substances are safe for use in cosmetics.  Titanium dioxide has been approved for use as a color additive in food, drugs, cosmetics, and contact lenses.  Zinc oxide is approved for use as a food ingredient, a color additive in drugs and cosmetics, and as a protectant for injured skin.
 
Concluded that these substances are safe for use in OTC drug products, including sunscreens, skin protectants, and other products.
 
-          The Scientific Committee for Cosmetic Products in the European Union:
Considered more than 100 titanium dioxide safety studies and concluded that these substances are safe for use in cosmetics.
 
-          Germany BfR, Federal Agency for Risk Assessment: 
In 2006, reviewed these two substances and found that the nanoparticles did not penetrate the skin, and that the biological properties of the nanoparticles were not necessarily different from those of larger particles.
 
-          The Australian government Department of Health and Aging:  
In 2006, published a comprehensive review of the science on zinc oxide and titanium dioxide and found no evidence that sunscreens containing these materials in nanoparticle form pose any risk. 
         
“The FDA has broad authority to ensure that personal care products and ingredients utilizing nanotechnology are safe for consumers and has consistently exercised that authority,” CTFA’s Bailey added.  “Sunscreens, some of which utilize sun-protecting nanoparticles, are required to go through an extensive pre-market review process to prove they are safe and effective.”
 
The FDA comprehensively regulates the safety of consumer health products.  Under the Federal, Food, Drug, and Cosmetic Act (FFDCA), FDA has erected a complex and comprehensive regulatory system to safeguard the public health.  This regulatory system has worked to ensure that, among other things, the food eaten by US consumers, the medical technology used by physicians and patients, and the personal care products used by countless citizens are among the safest in the world.
         
Based in Washington, D.C., CTFA is the trade association representing the cosmetic, toiletry, and fragrance industry in the United States and globally. Founded in 1894, CTFA has a membership of approximately 600 companies including manufacturers, distributors, and suppliers of the vast majority of finished personal care products marketed in the United States.

 

Sep
08
2006

Eczema Rates Stabilizing in U.K.

Rates of eczema and hay fever in the United Kingdom appear to have stabilized, after charting a steady rise over recent decades.

However, the study also found that rates of systemic allergic reactions -- including the severe condition known as anaphylaxis -- have surged in the past 20 years.

The researchers analyzed data gathered from numerous sources: national surveys, primary care doctors, prescription and hospital admission records, and death records.

Over the past three decades, diagnoses of allergic rhinitis and eczema in children have tripled, but there appears to have been a recent decrease in the prevalence of symptoms. Hospital admissions for eczema have stabilized since 1995, the researchers found, while admissions for allergic rhinitis have decreased to about 40 percent of their 1990 levels.

Between 1971 and 1991, the number of consultations with family doctors about hay fever increased by 260 percent and by 150 percent for eczema. However, these rates have stabilized in the past 10 years, the study said.

Hospital admissions for anaphylaxis have soared by 700 percent, for food allergy by 500 percent, and for the skin allergy urticaria by 100 percent.

Prescriptions for all types of allergies have increased since 1991.

The researchers said that some of the trends could be related to changes in medical practice and care but could also be explained by changes in the sources of allergic disease.

The study was published in the current issue of Thorax.

HealthDay News, September 7, 2006

Sep
06
2006

CTFA Requests Public Comments on Skin Absorption

The Cosmetic, Toiletry, and Fragrance Association (CTFA) is requesting public comments by September 25, 2006, on a new Safety Evaluation Guideline addressing the topic of Skin Absorption.

The guideline describes in vitro test methods for evaluating skin absorption.

The CTFA Safety Evaluation Guidelines provide manufacturers with guidance regarding the use of preclinical and clinical safety testing as a means to substantiate the safety of both ingredients and finished cosmetic products.  They are part of the CTFA Technical Guidelines series.

 Each Guideline undergoes an extensive development and review process by CTFA technical committees and staff, as well as public review by CTFA member companies, nonmember companies, federal government agencies, and scientific professional societies. 

An electronic copy of the draft guidelines is available from the CTFA Public Affairs Department by contacting Lisa Powers, (202) 446-0489 or email at powersl@ctfa.org.

Sep
05
2006

FDA Seeks Ban on OTC Skin Bleaching Products

The FDA is seeking to ban over-the-counter sales of skin bleaching drug products.

The FDA cites the possible risk of cancer and skin discoloration from hydroquinone typically found in these products.

However, those cancer studies were done on rats, not people.

"The actual risk to humans from use of hydroquinone has yet to be fully determined," the FDA states in its proposal, published in the U.S. government's Federal Register.

The type of skin discoloration noted by the FDA is called exogenous ochronosis, a darkening of the skin. The FDA cites research linking the condition to hydroquinone use.

The FDA isn't proposing a ban on prescription skin bleaching drug products. But all such products would need to submit a new drug application for the FDA's review.

Not all skin lighteners contain hydroquinone. The FDA knows of 200 products containing hydroquinone in strengths from 0.4% to 5%, about two-thirds of which "appear to be marketed as OTC [over-the-counter] drugs," says the FDA.

The FDA is taking comments on its proposal until Dec. 27.

Expert's Views

WebMD spoke with dermatologist Susan Taylor, MD, of Society Hill Dermatology in Philadelphia, and the Skin of Color Center in New York about the FDA's proposal.

"I feel that hydroquinones are safe and effective treatment for pigmentary disorders," Taylor says. "I feel comfortable recommending that my patients continue to use hydroquinones if they have a pigmentary disorder."

"I think the evidence is quite weak with the link between hydroquinones and cancer," Taylor tells WebMD.

"Data on rats and mice cannot necessarily be extrapolated to human data," she says.

"In Africa, people have used hyrdoquinones for long periods of time ... meaning years, 10, 20, 30, years ... and at high concentrations," Taylor says. "We've not seen a proliferation of various types of cancers reported from that population.

Exogenous ochronosis is rare in the U.S., Taylor notes.

"If you look at the case reports, it's probably less than 200," Taylor says. "So it's really not a significant problem here in the United States."

Millions of Users

Taylor points out that "many patients have disorders that are truly disfiguring and devastating. And these conditions can be improved significantly with hydroquinone products."

"It's important therapy and it's used by millions and millions of people," Taylor says.

She says hydroquinone products are primarily used to lighten dark areas of the skin due to conditions including injury, rashes, acne, and sun damage.

"So there are real problems and this is a real solution," Taylor says. She adds that filing new drug applications can cost millions of dollars.

"My concern is that we could lose prescription products that we have," Taylor says. "That would have major consequences, I think."

"It's safe, effective; it's the gold standard, and I think our patients would benefit from continued use for these problems. I think those three points sum it up for me," Taylor says.

SOURCES: U.S. Government Printing Office, Federal Register, Aug. 29, 2006; vol 71: pp 51146-51155. Susan Taylor, MD, Society Hill Dermatology, Philadelphia, Skin of Color Center, New York.

By Miranda Hitti, WebMD, August 30, 2006

Aug
30
2006

Combating Cultural Stress

By Howard Murad, MD

Find out how spa professionals can combat cultural stress in today's society.