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Overexposure to the sun's harmful ultraviolet radiation (UVR) kills 60,000 people a year, but most of these deaths are almost entirely preventable through simple protective measures, according to the World Health Organization.
UVR causes sunburn, triggers cold sores and ages the skin, according to its report, the first to outline the global health burden of sun exposure. Simple measures, such as covering up when in the sun, could cut the deaths, the BBC reported on Thursday. "We all need some sun, but too much sun can be dangerous -- and even deadly," said Dr Maria Neira, Director for Public Health and the Environment at WHO.
Of the 60,000 deaths, 48,000 are caused by malignant melanomas and 12,000 by other skin cancers, the report found. Small amounts of UVR are needed for good health and play an essential role in the production of vitamin D by the skin.
HealthDay News, 6/27/2006
Simply asking patients to map their moles on a drawing of their back after a monthly skin self-exam is an easy, low-cost way of reducing melanoma deaths, researchers report.
Melanoma is the deadliest form of skin cancer. It has a 95 percent survival rate if it's detected early but only a 16 percent survival rate if it's detected after it has begun to spread.
One of the best methods of detecting melanoma and other skin cancers is for patients to conduct monthly skin self-exams. However, it can be difficult for patients to accurately examine their skin without a method of remembering the location and size of existing moles, the study noted.
"Most melanomas are discovered by patients. So, we looked for a way to improve the accuracy of skin self-exams. Conducting the skin self-exam with the help of a diagram showing the location of moles, scars and other marks on the skin can help a person more easily notice any changes or new lesions, which are important warning signs for melanoma," study co-author Dr. Martin A. Weinstock, of Veterans Affairs Medical Center in Providence, R.I., said in a prepared statement.
The study, published in the August issue of the Journal of the American Academy of Dermatology, included 88 people who were educated about skin cancer and skin self-examination. The researchers took digital photos of the patients' upper and lower backs and instructed the patients to perform a self-exam before their next visit.
The patients were randomly selected to receive either a blank piece of paper (46 patients) or a "mole-mapping diagram" (42 patients). Those who received the diagram were told to draw their moles on it before their return appointment.
Between the patients' initial and return visits, the researchers randomly altered the photographs of the patients' backs, adding the image of a lesion. On their return visit, the patients were asked to indicate any changes on their photos.
Of the patients who received the mole-mapping diagrams, more than half were able to identify the changes made to their photos.
"The results suggest that asking the participants to create a mole-mapping diagram may improve the accuracy of skin self-exam, particularly identifying a new lesion," Weinstock said.
HealthDay News, 7/20/06
Educating the siblings of melanoma patients about their own cancer risk encourages them to undergo regular skin self-examinations that can catch the disease early, researchers report.
"For skin self-examination, we found that an intensive education intervention has a moderately strong effect among siblings of melanoma patients -- with intervention increasing the likelihood they will carefully examine their skin by 82 percent," said study author Alan Geller, a research associate and professor in the department of dermatology at the Boston University School of Medicine.
Experts estimate that the brothers and sisters of people with melanoma face two to eight times the usual risk for the disease.
However, the Boston study found that melanoma education does not boost the use of sunscreen or visits to the dermatologist in this high-risk group.
Melanoma arises from pigmented cells called melanocytes which can rapidly spread throughout the body. Prolonged exposure to the ultraviolet rays of the sun or a tanning bed elevate the risk for developing the disease.
According to the American Cancer Society, roughly 62,000 Americans will be diagnosed with melanoma this year, and more than 7,900 will die as a result. The researchers note that almost 630,000 Americans are already living with the cancer.
Such figures underscore the fact that melanoma is a growing problem in the United States. Diagnoses are up by a factor of 15 over the last 50 years, the authors noted. And while other cancer death rates having been dropping in recent decades, melanoma mortality numbers have risen by 28 percent over the last 25 years.
To gauge to what degree screening education might improve early detection among high-risk groups, Geller and his team focused on 494 brothers and sisters of 360 patients diagnosed with melanoma in the Boston vicinity shortly before the two-year study began in 1998.
All the siblings were white and over the age of 18. Almost all had health insurance, and none had a prior melanoma diagnosis.
A little less than half the siblings participated in a one-year screening education program, where they were offered a combination of motivational and counseling support by phone, printed material specifically tailored to each patient, and information on free screening facilities.
The other half of the siblings received no intervention beyond what the researchers viewed as "standard procedure": the informing of the initial melanoma patient that his or her siblings and parents are themselves at higher risk for the disease and should seek screening.
Surveys were conducted at the start of the study and six and 12 months down the line, although not all the patients completed all the polls.
The researchers found that after six months, siblings exposed to the program had better improvements in their knowledge about melanoma. By 12 months, participants in the program had fewer practical or psychological obstacles (such as how to find and pay for a dermatologist, or disliking sunscreens) to keeping watch on their skin, seeing a doctor, or using sun protection.
Most important, the program participants were more likely to conduct a careful self-examination compared to non-participants.
By six months, 67 percent of the participants conducted thorough self-exams, including examining the back, as compared with 52 percent of non-participants.
However, the education effort did not impact on either the routine use of sunscreens or wearing sun-protective clothing.
As well, no difference between the groups was found for seeking a dermatologist-conducted screening, although the frequency of such screenings doubled among all the siblings by 12 months.
The news is still good, however, because self-exams are the most basic form of spotting melanoma.
"I'm pleased with the results," said Geller, "because I think skin self-examination is a really important technique that should be learnt. And the beauty of this whole thing is that melanoma is the only visible tumor. So every family member can play really strong role in this -- helping if the subject can't look at his or her back. So this is basically a family education program."
Marianne Berwick, head of the Cancer Epidemiology and Prevention Program at the University of New Mexico Health Sciences Center, Albuquerque, said the study has the potential to help health professionals promote early detection and lower the melanoma death rate.
"Of course, we don't yet have any direct proof that skin self-examination will prevent mortality," said Berwick, who is also associate director for population science for the Cancer Research and Treatment Center at the university center. "But it's something that we think might help. So, my view is that this finding will be a valuable building-block in helping to direct a cancer-education message that will get people to engage in efforts that could be helpful in the long-run."
A second study, also published in the August issue of Cancer, further explored the potential benefits of melanoma education interventions.
A team of Australian researchers found that men over the age of 50 are more likely to get screened for the disease if they are fully informed about major risk factors and are encouraged by their doctor.
The authors, led by Joanne Aitken of the Viertel Centre for Research in Cancer Control at the Queensland Cancer Fund in Brisbane, focused on the screening habits of 3,355 men over the age of 50 who were exposed to a melanoma education effort targeted at people over the age of 30.
Although the intervention boosted screening generally, clinic data revealed that the strongest rise occurred among men over 50.
Aitken and her colleagues noted that among males 50 and over, self-exams doubled by the end of the program, while physician-led screenings increased four-fold.
Phone surveys revealed that the screening increases among the men were linked to a better recognition of their own risk factors, a more positive outlook on screening, and concern over an existing mole or having undergone a prior removal of a mole.
Increased awareness is important among this group, the researchers said, because men over 50 currently account for almost half of all melanoma deaths in developed countries.
By Alan Mozes, HealthDay News, July 12, 2006
Specific hormones may play a key role in longevity and healthy aging, two new studies suggest.
Researchers found one hormone, adiponectin, at higher-than-average concentrations in 100-year-old women, while another study found that stimulating the body's production of growth hormone brought a youthful pep back to people in their 60s to 80s.
Both studies were presented Wednesday at the 6th International Congress of Neuroendocrinology, in Pittsburgh.
In the first study, Dr. Agnieszka Baranowska-Bik and colleagues from the University of Poland studied 133 women from 20 to 102 years of age, including 25 women who were 100 to 102 years old. The researchers were particularly interested in the women's levels of adiponectin.
Adiponectin is made by fat tissue and may be an important determinant of longevity. It is a peptide protein with anti-inflammatory properties that helps keep blood vessels clear of fatty deposits. Adinopectin also plays an important role in metabolism, particularly in the regulation of cholesterol and sugar.
Low levels of adiponectin may contribute to obesity, insulin resistance, diabetes or plaque deposits in the arteries. This combination of conditions is also called metabolic syndrome.
"We found significant differences in the centenarian women compared to other groups," Baranowska-Bik said. "We found that our centenarian women were healthier than the other women."
"The most important finding was that adiponectin levels were significantly higher in centenarian women," Baranowska-Bik added. "This may be connected with metabolic status and also with getting old and longevity."
The Polish team found that the "100-plus" group of women, in addition to having significantly higher levels of adiponectin, also had much lower levels of both insulin and the fat hormone leptin. They also scored better with respect to insulin resistance and total cholesterol.
Moreover, compared with the obese women, the oldest women had significantly fewer signs of high blood pressure and other symptoms of metabolic syndrome. "In addition, these women had significantly lower incidence of high cholesterol and insulin resistance, which are the symptoms of metabolic syndrome," Baranowska-Bik said.
The second study dealt with improving physical functioning in older adults by increasing the body's production of growth hormone.
Aging results in a lower level of growth hormone that, in turn, brings on steady declines in muscle mass, strength and exercise capacity. This can lead to a level of frailty that brings an end to independent living.
Lead researcher Dr. George R. Merriam, of the University of Washington/VA Puget Sound Health Care System, said his team sought to determine if hormonal and functional declines were related, and if boosting growth hormone levels might help halt or reverse that decline.
In their study, Merriam and his colleagues studied the effect of the growth-hormone stimulator capromorelin on 395 men and women 65 to 84 years old. Capromorelin is an investigational medication developed by the Pfizer drug company.
All of the participants had some mild limitation in their physical functioning. During the year of the trial, some patients received capromorelin, while others were given a placebo.
Merriam's group found that, compared with a placebo, capromorelin, at any dose, caused an increase in growth hormone production. In clinical terms, this treatment resulted in an increase in muscle mass, improved heel-to-toe walking, and better stair-climbing ability.
"After six months people on the active drug showed improvement in tandem walking, and they continued to show improvement at 12 months," Merriam said. "At 12 months there was also a significant improvement in stair-climbing in the treatment group."
But whether capromorelin will be available commercially anytime soon is problematic, Merriam said.
"It's very difficult to get a drug for normal aging on the market, because the FDA does not consider aging to be a disease and therefore sets the bar very high," he said. "I would not consider these results conclusive. Drugs in this category may have hope for improving physical function and thereby hopefully prolonging older people's ability to live independently."
One expert is cautious about supplementing hormone levels to fight aging, because scientists simply doesn't yet understand the consequences of long-term use of these agents.
"The problems with all the hormones is that they have other effects," said Rafael de Cabo, an investigator at the Laboratory of Experimental Gerontology, part of the U.S. National Institute on Aging.
There can be many possible unintended effects, de Cabo said. "Before you can even think of giving these to humans, you have to be sure it is safe and doesn't have other implications," he said.
"Any time you try to tweak the neuroendocrine system, all the knobs are interconnected, so if you move one up or down there is an immediate response from the rest of them," de Cabo said. "It is not a golden bullet or an easy shot to fix the metabolism by a single compound."
By Steven Reinberg, HealthDay News, June 21, 2006
Blacks and Hispanics with melanoma, the potentially deadly skin cancer, tend to have it diagnosed at a later, more advanced stage than whites, researchers report.
Over the past decade, melanoma has become more common, with the rate of new cases increasing 2.4 percent every year in the United States. Because whites are at higher risk for the disease, most prevention and detection efforts have targeted them.
This may be why survival rates among whites have increased from 68 percent in the 1970s to 92 percent today. Unfortunately, the same improvement in survival hasn't been replicated among blacks and Hispanics, the University of Miami researchers noted.
"We found that patients who were black and Hispanic were diagnosed later for melanoma than white patients in Miami-Dade County, Florida," said lead researcher Dr. Robert Kirsner, professor and vice chairman of dermatology and cutaneous surgery at the University of Miami Sylvester Comprehensive Cancer Center.
Their findings appear in the June issue of the Archives of Dermatology.
In their study, the researchers looked at 1,690 melanoma cases reported in Miami-Dade County between 1997 and 2002. Among these, 1,176 occurred in white patients, 485 in Hispanic patients and 29 in non-Hispanic black patients. The population of whites and blacks in Miami-Dade County is approximately the same.
Compared with whites, the Hispanic and black patients were more likely to have advanced-stage melanomas. Sixteen percent of Hispanics and 31 percent of blacks had cancer that had metastasized -- spread to other organs or tissues -- compared with 9 percent of whites.
Moreover, 52 percent of black patients had regional or distant-stage melanoma, the most severe stages, compared with 26 percent of Hispanic and 16 percent of white patients.
Kirsner isn't sure why these differences exist. It's possible that blacks and Hispanics have a more aggressive type of melanoma, he speculated. "More likely, there is less awareness among patients and health-care providers that melanoma can occur in ethnic populations and patients with darker pigmentation," Kirsner said.
As a consequence, these patients aren't screened as often, and lesions are not detected as early as in the white population, Kirsner said. "So a diagnosis is delayed until a late stage and that correlates with worse survival," he said. "Patients' diagnoses with thin melanomas have nearly a 100 percent survival. However, if it has spread, then survival goes down to 16 percent. So survival is worse in Hispanics and blacks."
This is a public health issue, Kisner said. "Greater awareness is needed both by doctors and patients. Awareness by patients and health-care providers can, hopefully, turn that tide and lead to the same improvement in survival that has been demonstrated in white populations."
Dr. Jeffrey C. Salomon, an assistant clinical professor of plastic surgery at Yale University School of Medicine, agreed that it's important to educate blacks and Hispanics about the risk of melanoma.
"Clearly the awareness of melanoma risk in dark-skinned populations is less than in fair-skinned, sunburn-prone people. More could and should be done to raise the awareness that melanoma is not a disease exclusively of Caucasians," he said.
"Pigmentary changes on soles of feet, on palms, and under nails may be the only early warning sign of trouble in dark-skinned people," Salomon said. "This message needs to be sent out to people at risk. You can never make a diagnosis without thinking of it."
But another doctor thinks that since melanoma is largely a disease that strikes Causasians, it might be unwise to divert too many health-care dollars from education programs for whites.
"If you stop to think about how much impact you are going to have on melanoma by infusing money into the system, because melanoma is about 50 times more common in whites than in blacks, the fact is you have a lot more bang for your buck in reducing death from melanoma if that money is targeted at whites," said Dr. Jean-Claude Bystryn, a professor of dermatology at New York University School of Medicine.
Bystryn said spending the same amount of money on blacks and whites to reduce deaths from melanoma by 50 percent would save 500 lives among whites compared with 15 among blacks in Dade County.
"From a public health point of view, it is better to focus on the group that is most at risk," Bystryn said
HealthDay News, June 19, 2006
Skin cancer is the most common form of cancer suffered by people, accounting for more than half of all malignancies, according to the American Cancer Society.
So when you're out lounging in the sun this summer, working on that tan, remember that you're putting your body's largest organ at risk for cancer.
But preventing skin cancer can be as easy as limiting sun exposure between 10 a.m. and 2 p.m. and keeping a close eye on your skin for suspicious growths and moles. And recent research breakthroughs may aid treatment, particularly with melanoma, the most deadly form of skin cancer.
People rarely die from nonmelanoma skin cancer, which includes basal cell and squamous cell cancers. These malignancies claim the lives of about 2,800 Americans each year, compared with more than 1 million new cases diagnosed annually.
"Basal cell skin cancer is like a rust spot on a car door," said Dr. Ken Gross, a clinical professor of dermatology at the University of California, San Diego. "If you ignore it, it'll eat through that spot, but it will never reach the engine or the transmission."
Melanoma is a far more menacing threat. There are expected to be 62,190 new cases of melanoma diagnosed in the United States this year, and about 7,910 deaths from the cancer. Overall, the mortality rate for the disease has increased by 50 percent since the 1970s, according to the American Cancer Society.
However, new research could help treat, and perhaps prevent, melanoma. In a study published in the November issue of the New England Journal of Medicine, researchers found that there are at least several distinct types of melanoma, each potentially responding to its own individual treatment.
"It's very clear the landscape is changing because more and more genetic abnormalities are being found, and there are targeted therapies available for some of them," said study author Dr. Boris Bastian, an assistant professor of dermatology and pathology at the University of California, San Francisco.
Bastian found that there are differences between melanomas arising from skin on different parts of the body: chronically sun-damaged skin, skin without sun damage, skin rarely exposed to the sun, and mucous membranes.
"Therapies may only work for specific genetic abnormalities," Bastian said. "We're going to see, like in other cancer types, a breakup of the disease for treatment."
People at greatest risk for skin cancer are those who spend a lot of time in the sun and have fair skin. "We know that sunburn and chronic sun exposures bump up the risk of skin cancer," Gross said.
Family history also plays a part in determining whether you're apt to get skin cancer, he added. People with relatives who have contracted skin cancer should pay closer attention to abnormalities on their skin.
"Things that might be a little suspicious on someone else might be quite suspicious on you, and you might want to worry a little more," Gross said.
People with freckles or moles are at increased risk of melanoma, so they should inspect their moles often and keep track of any changes in them. You also should note any changes in your skin, including odd sores, lumps, blemishes or markings.
"Pay attention for the ugly duckling, the mole that doesn't fit in, the mole that has changed," Bastian said.
Once you've found a skin lesion or mole that gives you pause, you should go to a dermatologist as soon as possible to have it looked at, Gross said.
He recommends a dermatologist over your family physician because the specialist knows more about the different types of skin blemishes and cancers and can make a more informed diagnosis.
"Most patients come in saying, 'I've got a mole, and it's changing, that makes me suspicious. I want it biopsied,' " Gross said.
People might want to consider having regular skin screenings, particularly as they get older, he said. That way, doctors can track the progress of various blemishes and moles and note any suspicious changes.
Even if a growth has been removed, Gross recommends paying close attention to the place it came from. It could recur without warning.
"The most important thing you can remember is just because I say something is alright, that doesn't make it so," Gross said.
Gross said people who want to avoid skin cancer need only use common sense.
"When we go out, we wear a brimmed hat and long sleeves," he said. "I don't sunbathe, and I stay as far away from indoor tanning beds as possible."
Sunscreens can be useful, but are not a solution you should count on, Bastian said.
"Usually, people don't put on enough sunscreen," he said. "My recommendation is not to rely on sunscreens, but to avoid the sun during peak hours."
HealthDay News, June 16. 2006
British scientists have discovered a tantalizing new wrinkle in our understanding of smoking's unhealthy effects.
Middle-aged smokers whose faces were heavily wrinkled were five times as likely to have chronic obstructive pulmonary disease (COPD) than smokers whose faces were relatively smooth, the study found.
The authors speculated that both COPD and wrinkling may be linked by a common mechanism and that facial wrinkling might indicate susceptibility to the potentially deadly lung disease.
It's unclear, however, what kind of clinical relevance the findings hold.
"It's certainly biologically plausible," said Dr. Norman Edelman, chief medical officer for the American Lung Association. "This may be of use in educating patients but, in terms of detection of lung disease, we [already] have a simple breathing test. We don't have to look for wrinkles."
The research appears in the June 14 online edition of Thorax, which is published by the British Medical Journal.
COPD refers to a group of progressive chronic lung diseases, including emphysema and bronchitis, that block the airways and restrict oxygen flow.
Some 13.5 million Americans suffer from COPD, and the World Health Organization predicts that the condition will become the third leading cause of death worldwide by 2020.
Smoking is the biggest risk factor for COPD, and dermatologist have long noted that smoking causes premature aging of the skin.
However, not all smokers go on to develop COPD. "Obviously, people vary in their response to what's in the smoke," Edelman said.
In the study, the team wanted to see if genetic factors that predispose smokers to COPD might also predispose them to wrinkles.
The researchers, based at Royal Devon and Exeter NHS Foundation Trust, analyzed data on 149 current and former middle-aged smokers, 68 of whom (45.6 percent) had COPD. The participants came from 78 families.
Eighty-three percent had no facial wrinkling or only minor lines, but close to 17 percent had considerable wrinkling.
Lung strength and function, measured in all participants, turned out to be significantly lower in those with extensive wrinkling than in those with smoother faces.
People with heavy wrinkles were also five times more likely to have COPD than those without wrinkles. People with facial wrinkling also had triple the risk of suffering from more severe emphysema.
The authors theorized that smoking-linked changes in cells' collagen and elastin may be important for the development of both lung disease and wrinkles.
The findings are more likely to be helpful in spurring new research than in providing any direct benefit to patients, Edelman said.
"I think this will be of use to basic biologists," he explained. "Maybe you can start doing experiments on the skin, maybe that's an easier model to use than the lung to figure out what the mechanisms are."
HealthDay News, June 14, 2006
Women under 40 are showing higher incidences of nonmelanoma skin cancer, according to a new study appearing in The Journal of the American Medical Association. Rates for basal cell and squamous cell cancers have increased from 13 per 100,000 women to 32 per 100,000 over the last 30 years. Experts cite tanning as a possible reason for the rise. “Tan is still accepted as a sign of health and a sign of beauty,” says Leslie Christenson, MD, dermatologist and study author at the Mayo Clinic in Rochester, MN. Christenson recommends prevention at an early age, limiting sun exposure and always applying sunscreen.
American males aren't getting or heeding warnings on sun protection, researchers report, with the bulk of magazine ads for sunscreen appearing in publications aimed at women, not men.
A new U.S. study shows that 77% of the 783 sunscreen ads reviewed were published in women's magazines.
Researchers reviewed 579 magazines -- all May to September issues from 1997 to 2002 for 24 different publications.
While the average was about four ads for sunscreen per women's magazine, the average was less than one in each issue of parenting and family magazines. The average in outdoor and recreation magazines typically read by men was less than one per six issues.
"There's a huge opportunity to reach an untapped market," Alan Geller, an associate professor of research with the Boston University School of Medicine, said in a prepared statement. The ads should also better explain how to properly use sunscreen and other sun-care products, he said, as none of the ads contained the recommended guidelines for appropriate use of sunscreen.
His team published their findings in the May/June issue of the American Journal of Health Promotion.
"We know that men know much less about sun protection than women," Geller said, adding that "research has shown us that many, many people use sun protection products and still get burned." These advertisements provide a good opportunity to educate people on how to use sunscreen properly, he added.
"With my contacts, I've argued that advertising and communications should go on in boating, tennis and golf magazines," David J. Leffell, a professor of dermatology and surgery at the Yale School of Medicine, said in a prepared statement. Leffell was not involved in the study, but consults for a large U.S. manufacturer of sun-care products.
The results of the study show a need for working relationships between product marketing departments and advocates for skin cancer prevention, as well as more ads geared toward "potentially higher-risk groups such as children, men and outdoor recreation users," said Geller.
HealthDay News, May 29, 2006
Exposure to cats shortly after birth raises a child's risk of eczema, new research suggests.
The study, which tracked 486 children until the age of 1, was presented Sunday at the American Thoracic Society International Conference in San Diego.
While 27.6 percent of kids with cats as pets developed eczema in that time, only 17.8 percent of kids without cats developed the dry skin condition.
On the other hand, being around two or more dogs in the home conferred a slightly protective effect, said lead researcher Dr. Esmeralda Morales, a pediatric pulmonary fellow at the University of Arizona, in Tucson.
"Other studies have found that having cats or dogs at home seems to be protective against allergic disease, so we expected to have similar findings," Morales said in a statement.
Morales noted that the children in the study who developed eczema by the age of 1 might still wind up having a reduced risk of asthma or allergies later in life. "The findings do seem to add more questions about pets and asthma and allergies. Since there are a lot of contradictory data out there already, clearly it's a topic that needs further research," she added.