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A woman’s risk for breast cancer declines as she grows older,researchers conclude.That’s because as women age,their milk –producing glands(lobules)start to shut down.This natural process is called lobular regression,or involution.Since its believed that breast cancer originates in the lobules,a reduction in their size and number reduces cancer risk.The Mayo study of over 8,700 women found that those benign breast disease and little or no involution were twice as likely to develop breast cancer compared to women whose breast glandular tissues had been replaced with connective and fatty tissue.The researchers also found that 53% of women ,age 70 and older had complete involution.
Women who had never used hormone replacement therapy were more likely to have complete involution than those who did(22.9%vs.20.3%), the women researchers add.27% women who had no children had complete involution, compared to18% women who had more than three children. Breast-feeding had no impact on involution, the study found. This study is the first to establish that the extent of breast involution relates directly to risk for breast cancer.

Children who are successfully treated for brain tumours and leukaemia are more likely to have strokes later in life,says a new study.
Childhood cancer survivors,who received higher doses of cranial radiation therapy to kill the cancer,showed greater risk of stroke in later years.It is important because leukaemia and brain tumours are the most common types of childhood cancer,representing more than half of childhood cancers.
Other studies have shown that survivors of childhood leukaemia or brain cancer are also at higher risk for cardiac dysfunction,obesity,short stature,and hormone and neurocognitive deficits.The study found that leukaemia survivors were two to three times more likely to suffer a stroke than their siblings,whereas brain cancer survivors were eight to ten times more prone to have a stroke.

If you’re thinking about liposuction, forget the vacuum and say hello to the laser. The US Food and Drug administration has just approved a new, less- invasive technique for liposuctions better and safer than the traditional surgery.
“If you do traditional liposuction, you can make the skin look worse. It is pretty much like a deflated balloon,” said Bruce Kartz, director of the Juva Skin and Laser Center. “ This technology allows us to melt the fat and tighten the skin at the same time.”
Using a local anaesthetic, doctor insert a small tube with a laser under the skin. “As the laser tip comes into contact with the fat cells, it literally melts the fat,” said Karen Kim, dermatologic surgeon. The melted fat then drains away from the body. “There’s very minimal bruising. There’s minimal swelling afterwards. The incision site that you enter into the skin is very small, so you don’t even have to put a stitch into it,” Kim said.
The new procedure isn’t for everybody . Doctors say the laser system is best suited for targeting small fat deposits in otherwise healthy people, and it is not a cure for obesity.
“In the age of technology and cosmetic surgery, there are such dramatic improvements in technology that sometimes the hype goes beyond what can actually be accomplished,” said Paul Jarrod Frank, a dermatologic surgeon.
“There will never be a magic wand of cosmetic surgery.”

A remarkable new anti-viral polymer can be applied like paint and could help reduce the spread of germs in public areas and hospitals. The "biocidal paint" was developed by MIT's Alexander Klibanov.
In a graphic demonstration , a regular commercial glass slide and another one coated with alkylated PEI "paint" were sprayed with aqueous suspensions of Staphylococcus cells, and then incubated. Some 200 bacterial colonies are seen on the unprotected slide—and only 4 on the protected one.
Klibanov writes:
Our recent studies have resulted in a new, "non-release" strategy for rendering common materials (plastics, glass, textiles) permanently microbicidal. This strategy, involving covalent attachment of certain long, moderately hydrophobic polycations to material surfaces, has been proven to be very effective against a variety of pathogenic bacteria and fungi, both airborne and waterborne. This work continues along with a quest for creating material coatings with anti-viral and anti-sporal activities.
Klibanov and his colleagues found that the prickly polymer worked on bacteria; they tested it with the smaller flu virus and found the same effects. They applied droplets of a flu solution to glass slips painted with the polymer. After a few minutes' exposure, they were unable to recover any active virus from the samples, meaning the coating reduced the pathogen's abundance by at least a factor of 10,000.
How does it work? In the case of bacteria, the polymer seems to gouge holes in a microbe's cell wall and then spill out its contents. The polymer molecules stay rigid because they are all positively charged and repel each other; they are like strands of hair standing on end from a static charge. The spikes have sufficiently few charges, however, that they can breach bacterial walls, which repel strongly charged molecules. The polymer probably neutralizes flu because the virus has an envelope around it suitable for spearing, Klibanov says.

Some "chocoholics" who just couldn't give up their favorite treat to comply with a study to test blood stickiness have inadvertently done their fellow chocolate lovers - and science - a big favor.Their "offense," say researchers at Johns Hopkins led to what is believed to be the first biochemical analysis to explain why just a few squares of chocolate a day can almost halve the risk of heart attack death in some men and women by decreasing the tendency of platelets to clot in narrow blood vessels."What these chocolate 'offenders' taught us is that the chemical in cocoa beans has a biochemical effect similar to aspirin in reducing platelet clumping, which can be fatal if a clot forms and blocks a blood vessel, causing a heart attack," says Diane Becker, M.P.H., Sc.D., a professor at The Johns Hopkins University School of Medicine and Bloomberg School of Public Health.Becker cautions that her work is not intended as a prescription to gobble up large amounts of chocolate candy, which often contains diet-busting amounts of sugar, butter and cream. But as little as 2 tablespoons a day of dark chocolate - the purest form of the candy, made from the dried extract of roasted cocoa beans - may be just what the doctor ordered.Researchers have known for nearly two decades that dark chocolate, rich in chemicals called flavonoids, lowers blood pressure and has other beneficial effects on blood flow. The latest Hopkins findings, to be presented Nov. 14 at the American Heart Association's annual Scientific Sessions in Chicago, identified the effect of normal, everyday doses of chocolate found in ordinary foods, unlike previous studies that found decreased platelet activity only at impractically high doses of flavonoids equivalent to eating several pounds of chocolate a day."Eating a little bit of chocolate or having a drink of hot cocoa as part of a regular diet is probably good for personal health, so long as people don't eat too much of it, and too much of the kind with lots of butter and sugar," says Becker.In the study, 139 people Becker - whom Becker somewhat tongue in cheek calls "chocolate offenders" - were disqualified from a much larger study looking at the effects of aspirin on blood platelets. The Genetic Study of Aspirin Responsiveness (GeneSTAR) was conducted at Hopkins from June 2004 to November 2005 and enrolled more than 500 men and 700 women participants nationwide.Shortly before aspirin dosing began for the subjects, they were told to stay on a strict regimen of exercise and to refrain from smoking or using foods and drinks known to affect platelet activity. These included caffeinated drinks, wine, grapefruit juice - and chocolate.The non-compliers - who admitted to eating chocolate - were a diverse group who got their flavonoid "fix" from a variety of sources, including chocolate bars, cups of hot cocoa, grapes, black or green tea, and strawberries. And while they were excluded from the aspirin study, Becker and her team scoured their blood results for chocolate's effect on blood platelets, which the body recycles on a daily basis.When platelet samples from both groups were run through a mechanical blood vessel system designed to time how long it takes for the platelets to clump together in a hair-thin plastic tube, the chocolate lovers were found to be less reactive, on average taking 130 seconds to occlude the system. Platelets from those who stayed away from chocolate as instructed clotted faster, at 123 seconds.In another key test of urine for waste products of platelet activity, primarily urinary thromboxane (11-dehydro-thromboxane B2), scientists found that chocolate eaters showed less activity and waste products on average, at 177 nanograms per millimol of creatinine, versus an average of 287 nanograms per millimol of creatinine in the group that abstained.Participants ranged in age from 21 to 80; 31 percent were black and the rest were white. In total, more than 200 different tests of platelet reactivity were performed and analyzed in the study. Because whole blood contains other cells that affect platelet aggregation, testing was repeated using a purified version of test samples made up of strictly platelet-rich plasma.None of the "offenders" had previous histories of heart problems, such as a heart attack, but all were considered to be at slightly increased risk of heart disease because of family history. Fifty percent of women participants were postmenopausal."These results really bring home the point that a modest dietary practice can have a huge impact on blood and potentially on the health of people at a mildly elevated risk of heart disease," says study co-author Nauder Faraday, M.D., an associate professor at Hopkins. "But we have to careful to emphasize that one single healthy dietary practice cannot be taken alone, but must be balanced with exercise and other healthy lifestyle practices that impact the heart."

Students, don't cringe, but new research suggests that the very act of taking a test is enough to enhance long-term memory. Furthermore, testing helps students remember not only what they studied for the test, but also related, non-tested concepts.
The results "imply that as long as students retrieved a concept, other related concepts should also receive a boost," the researchers write in the November issue of the Journal of Experimental Psychology: General.
In one experiment, a group of 84 undergraduates were given two sets of facts about the biology and lifestyle of tropical toucan birds. The researchers divided the students into three groups, with one group taking a test immediately after studying the first set of facts, before receiving the second set to study for a final test.
Another group received both sets of toucan facts at once, before being dismissed. A third set of students served as a control group, and only studied the first set of toucan facts before being dismissed.
All the students came back one day later to take a final test containing questions culled from both the first and second set of toucan facts. Students tested twice significantly outperformed both the students who did not take a previous test and the control group.
Based on the results, the researchers, led by Jason Chan of Washington State University in St. Louis, recommend that "educators might consider increasing the frequency of testing to enhance long-term retention for both the tested and the related, non-tested material."

French researchers say they've discovered a natural painkiller in human saliva that's several times more potent than morphine used in animal studies.
The researchers have named the pain inhibitor opiorphin, because it acts on the same pathways as morphine and other opiate painkillers. The finding could lead to improved pain medications because opiorphin is a naturally occurring molecule that is quickly metabolized, according to a report by researchers at the Pasteur Institute, in Paris.
Not much is known as yet about opiorphin, said study author Dr. Catherine Rougeot, director of the institute's Laboratory of Pharmacology of Neuroendocrine Regulation.
"We found it in saliva, that was the first step," she said. "Now, we are exploring its presence in other human biological tissues. Maybe it is localized in the blood, the brain. Now, I cannot answer."
It's not even known where in the body the substance is produced, Rougeot added. "We need more information to answer this question. Now, we need to characterize its function at physiological levels and learn by which tissues it is produced," she added.
The study was published in this week's issue of the Proceedings of the National Academy of Sciences.
The discovery was made after the researchers identified a powerful pain-inhibiting molecule in rats. Their search for a similar molecule in humans turned up opiorphin. In rat studies, injections of 1 milligram of opiorphin per kilogram of body weight equaled the painkilling power of 3 to 6 milligrams of morphine per kilogram. Opiorphin was equally effective against chemical-induced inflammation and acute physical pain.
In addition to studying opiorphin, Rougeot and her colleagues plan to make and study variations of the original molecule. "It is important to mimic such compounds," she said.
A painkiller arising from the research could have important applications for human use, Rougeot said. "Opiorphin is natural, so it is quickly metabolized," she said, so its effects on the body would be more limited than those of existing painkillers.
Rougeot already has contacted a pharmaceutical company about funding for more research on opiorphin. "To complete this program, I need very much money," she explained.
Identification of opiorphin is "a potentially very significant finding," said Dr. Max Kelz, an assistant professor of anesthesiology and critical care at the University of Pennsylvania. "This new compound could serve as a potentially useful therapy for fighting pain in a number of conditions."
Kelz agreed that the discovery was just a beginning. "More has to be done to elucidate how this affects other endogenous painkillers," he said. "But the results are certainly promising."
Dr. Ed Ross, director of the pain management center at Brigham and Women's Hospital in Boston, said opiorphin could be an important addition to the only other natural painkillers found in the human body -- endorphins.
"Endorphins have been around for quite a while, but they are weak and have a short half-life, so the problems in using them clinically are very significant," Ross said. "Now, this is a compound that has much more strength than the endorphins. It also suggests a potential for other synthetic compounds that work on different receptors that we have known before, and, for a pain doctor, that is very significant."
Another paper in the same issue of the journal described the discovery of toxins from two species of snails that hold promise for relief of severe nerve pain such as sciatica. The toxins lock onto nerve cell receptors to block nerve pain, said the report by researchers at the University of Utah.
One of the toxins, designated Vc1.1, is being developed by an Australian company and already is undergoing trials in human patients. It is administered by injection.
It may be possible to develop a version that could be taken orally, but that might require 10 years, said a statement by J. Michael McIntosh, a research professor of biology and a member of the team reporting the discovery.
"There really is no highly effective treatment available for this kind of severe pain, so having a new way to treat it is exciting," he said.

That tattoo you decided to get in college may look cool, but it might also be decreasing your skin’s sensitivity to touch.
University of Northern Colorado psychologist Todd Allen tested 21 undergraduates who had gotten tattoos within the last couple years, most commonly on their lower back for females and upper arm for males, and found tattooed areas were less sensitive than matching non-tattooed areas.
Allen tested sensitivity with an aesthesiometer—a sort of caliper with two plastic points. The points were gradually moved closer together on the skin until the person could only feel one point of pressure instead of two. Tattooed individuals felt this point sooner on their tattoo than on the same part of the corresponding non-tattooed body part.
Allen told LiveScience he sees three possible explanations for the change in sensitivity, all of which he said are difficult to test.
One possibility is that the tattoo ink disrupts the transmission of pressure from the surface of the skin to receptors deep in the skin
Another is that the tattoo gun. could over-activate the receptors so that they become less sensitive.
The third, and least likely possibility to Allen, is that “somehow the tattooing process has just damaged or killed the receptors in the skin.". This possibility is unlikely because these receptors generally grow back when damaged, he explained.
To test the third possibility, researchers would have to look at a tattooed cadaver and stain the nerve endings under the tattoo to see if they were damaged.
The decrease in sensitivity doesn’t hinder tattooed individuals, mostly because tattoos aren’t in places that require sensitivity. “It’s not a big deal in reality,” Allen said.
Allen would like to explore whether the number or size of tattoos further affects sensitivity.

Risk of lymphedema is greatly increased when a posterior axillary boost of radiation is delivered after breast cancer surgery, researchers at the Fox Chase Cancer reported Wednesday during the 48th annual meeting of the American Society of Therapeutic Radiology and Oncology (ASTRO), being held this week in Philadelphia.
"Lymphedema can be a big problem for our patients," principal investigator Dr. Shelly B. Hayes told meeting attendees. "It's a long-term side effect, lasting for 6 months to as long as 1 or 2 years."
She presented findings for 405 patients with non-metastatic breast cancer at stage T1 or T2 and any number of positive lymph nodes. Patients were treated between 1995-2005 with lumpectomy and axillary lymph node dissection. Patients also received radiation to the breast and supraclavicular lymph nodes with a median dose of 46 Gy, and 45% received an additional dose to the posterior axillary nodes.
Dr. Hayes reported that 27% overall developed lymphedema. The risk of lymphedema was 31% in patients receiving an axillary dose and 23% in those receiving radiation to the supraclavicular nodes only.
Lymphedema severity was not significantly different, regardless of whether an axillary dose was delivered. Lymphedema was mild in 55%, moderate in 34% and severe in 10%.
The number of positive axillary nodes and nodal status were risk factors for the complication, as were older age and a higher body mass index.
Patients with four or more positive nodes were four times more likely to develop lymphedema if they received both supraclavicular and axillary radiation compared with their counterparts who received only supraclavicular radiation, Dr. Hayes reported.
On the other hand, Dr. Hayes said, recurrence rates were lower in patients who received the extra axillary boost than in those who received supraclavicular treatment only.
"This was a retrospective study," Dr. Hayes emphasized in an interview with Reuters Health before her presentation. "It's hard to say that the axillary radiation was causative. Dose didn't fall out as being significant, but most patients received the same dose."
And while cause and effect were not studied, and incidence rates only have been analyzed, Dr. Hayes suggested "people might take pause when considering an extra axillary dose of radiation."

Dreaded vaccinations could be as simple as sticking Band-Aid—ouchless and do it yourself. Early tests of skin patch vaccines are beginning in hundred of volunteers,one version designed to protect against the flu and another to prevent travellers’diarrhoea.
Patch developer Iomai Corp proposes that the mailman,not a doctor,deliver flu vaccine during a pandemic.
Once a vaccine is brewed,simply ship patches to people’s homes with instructions to slap one on.Doctors may not like the method.But the technology’s promise may be in developing countries.Unlike syringe-based vaccines,patches wouldn’t need refrigeration-nor pose the risk of reused needles,a continuing problem.

Crushing pills to make them swallow may cause serious side-effects that can sometimes be fatal.A group of experts,including pharmacists and lawers,said that pills are often coated with a special material that governs their release into the body,but crushing them disturbs the system.David Wright,who led the group,saidthat rather than crushing pills,people should take them in patches,liquids or inhalers.He also said that drugs like tamoxifen and morphine,which are used in the treatment of breast cancer,should never be crushed,as it cuold trigger a fatally fast release of the drug inside the body.Wright said that Nifedipine,the angina and blood pressure drug ,can cause dizziness,headaches and an increased risk of stroke or heart attack when consumed in crushed form.Crushing pills increase the risk of side-effects,of the patientgetting a large dose of a drug which should be released slowly,or a drug being cleared from the body to earlybefore it could do anythingFatalities can happen,although not that common.