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Revolutionary treatment for urinary incontinence developed Sydney. Oct 29: Scientists have developed a potential treatment for severe incontinence, the involuntary loss of urine from the bladder, that could benefit millions of sufferers worldwide. One of the causes of the most common type of urinary incontinence, known as stress incontinence, is when the sphincter muscle no longer dependably keeps urine in the bladder. University of Melbourne researchers have found a way of creating a ring of muscle from the patient's own body and transplanting it to the bladder where it acts as a replacement sphincter. The replacement sphincter is controlled by an implanted electrical stimulator that should, for the first time, give sufferers of severe stress incontinence, a reliable method of passing urine only when they want. "The only surgical solutions available until now have involved prosthetic devices that have had problems with leakage, failure and adverse tissue reactions," says University of Melbourne's Professor John Furness and one of the inventors of the treatment. "This treatment has the potential to revolutionise the management of severe urinary incontinence which afflicts tens of thousands of people worldwide. This is a miserable condition, and if not effectively managed, can result in people entering nursing homes or institutions because they are unable to cope," he says. "The most common cause of a defective sphincter muscle is trauma to the area, for example as a complication of prostate surgery in men, or more frequently in women as they reach menopause, particularly if they have had children," says Furness. Ginger, herbs help prevent cancer: Study (Go To Top) Washington, Oct 29: A recent study shows that common spices and herbs contain ingredients that may prevent the formation of major tumors, such as intestinal and prostate cancers. According to research presented on Tuesday at the American Association for Cancer Research, recent studies have shown that ginger extract and a traditional Chinese medicinal herb have notable cancer prevention potential. Drs. Ann M. Bode and Zigang Dong, researchers at the Hormel Institute, University of Minnesota, recently determined that ginger compounds might be effective in preventing and potentially treating colorectal cancer. The theory was tested on human colorectal carcinoma cells (HCT116) in athymic nude mice that are incapable of rejecting implanted human tumor cells. Following injection, the mice were weighed and tumors were measured by calipers twice each week. Overall results showed that tumor development was significantly slower in those mice fed gingerol. All mice in the control group developed tumors by day 28, as compared to day 38 for the gingerol group. Preliminary results also suggest that many of the tumors in the control group were invasive into the abdominal cavity, whereas the gingerol group appeared to be less invasive. "These results strongly suggest that our hypothesis on the value of ginger is correct", said Dr. Bode, lead author of the study. "As we continue to study the spice in other tumor areas, we hope it will translate into significant anti-cancer properties for humans". Following in the same line, a traditional Chinese herb Scutellaria barbata (SB), a species related to mint of the Labiate family, has also been used to treat several illnesses, including cancers of the liver, lung and rectum. In this study, presented by researchers from Union College in Nebraska, SB was found to slow the progression of prostate tumors in mice, suggesting potential chemopreventive effects. "We are finding that, in this case, the therapeutic value of natural herbs is presenting itself as clinically valid", said Brian Wong, Ph.D., of Union College, and lead author of the study. The most recent research data demonstrated that SB has a similar effect in the induction of apoptosis in a human prostate cancer cell line and also modulates the Poly ADP-Ribose Polymerase, an enzyme required for the detection of DNA strand interruptions of the same cell line. "These studies are extremely important and must be continued to help us understand better ways of preventing cancer which do not require extraordinary measures", said Raymond DuBois, M.D., Ph.D., of Vanderbilt University. Scientists unravel secrets of sleep (Go To Top) Washington, Oct 28: Researchers at the Johns Hopkins Institute have discovered a key step in the body's regulation of melatonin, a major sleep-related chemical in the brain. The findings appearing in the online section of 'Nature Structural Biology' reports finding the switch that causes destruction of the enzyme that makes melatonin - no enzyme, no melatonin. Melatonin levels are high at night and low during the day, and even at night, melatonin disappears after exposure to bright light. This response contributes to its normal daily cycle, but plagues shift workers and jet setters by leading to sleeplessness. To help understand melatonin's light-induced disappearance, the Hopkins researchers resorted to the enzyme that makes it, a protein called AANAT. One way cells turn proteins like AANAT on and off is by modifying them, attaching or removing small bits, such as phosphate groups, to particular spots along the protein's backbone. For AANAT, the key spot turns out to be building block number 31, the researchers have found. "We have discovered that addition and removal of the phosphate group at this position is the key step in regulating the enzyme's stability," Philip Cole, professor and director of pharmacology and molecular sciences in Hopkins' Institute for Basic Biomedical Sciences. To test the importance of the phosphate group to the enzyme's stability, research associate Weiping Zheng, Ph.D., developed a mimic of the key building block with the equivalent of a permanently affixed phosphate group. He inserted the mimic into the appropriate place in the enzyme. The altered enzyme stayed intact in the cells much longer than the normal enzyme, whose phosphate group can easily be removed, experts added. The researchers then determined how exposure to light accelerates removal of the phosphate and destruction of the enzyme, leading to a rapid drop off in melatonin. "Now we can fish for unknown players in the degradation of the enzyme and hopefully find the trigger than leads to its light- activated destruction," Zheng said. Viagra, the answer to prostate cancer patients: Study (Go To Top) Salt Lake City, Oct 26: A new study shows that Viagra will work in nearly 70 per cent of the men who have radiation- associated erectile dysfunction for years to come. However, the durability of the response is still under study. Michael Zelefsky, MD, of Memorial Sloan-Kettering Cancer Centre, N.Y., tells WebMD that the radiation-associated erectile dysfunction usually begins about six months after the patients have concluded therapy, but can occur at any time during or after treatment. In the new study, presented at the 45th Annual Meeting of the American Society for Therapeutic Radiology and Oncology, Zelefsky and his colleagues studied the "durability" of response by following 360 men with radiation-induced erectile dysfunction who initially responded to the drug. The results, he says, were surprising. "I didn't really expect them to still be taking the drug and I expected that for many men the effect would diminish with time". But after almost four years, 96 per cent of the men who initially responded to Viagra, were still taking the drug and all but six of those men said the drug was still effective. Zelefsky says the men who reported that Viagra stopped working were those who were treated with extremely high-dose external radiation. "The study is important since it shows that treatment with (Viagra) can deliver a durable response. We don't really know how often they are taking the drug. We know that with repeated use tolerance develops for many drugs and we expect it for this drug as well", says Richard Valicenti, MD, associate professor radiation oncology, at Thomas Jefferson University Hospital, in Philadelphia. If tolerance does develop, the new erectile dysfunction drug, Levitra, could be an option says Zelefsky. His group is conducting a study with this newly approved drug it will be sometime before the results are available. Meanwhile, he says that he is trying Levitra in men who don't initially respond to Viagra. Now, a simple blood test to detect cancer (Go To Top) Washington, Oct 23: Early detection of cancer is now possible by studying a protein that expresses itself during the onset of the disease. According to Case Western Reserve University scientists, who studied the changes in the protein by carrying out a simple blood test, understanding the processes that create this can help them in developing new therapy regimens that improve the chances of recovery. The research team discovered that the human body increases production of the protein clusterin as a signal of cell distress and provides a reliable gauge of the general health of a cell. The findings were reported in a recent issue of the scientific journal Cancer Biology and Therapy. According to the study, clusterin should behave in blood as it does in cells examined in the laboratory. The team observed clusterin levels rise in response to the presence of cancer. Researchers said this rise would indicate that if a baseline clusterin level was established for a healthy person, a simple blood test could detect any deviation in clusterin levels, indicating the potential presence of cancer. The researchers used cells from humans and mice to establish their findings. "Trying to understand how genes influence cancer requires either a guess or mice, because we can't expose humans to the radiation that helped us get to these findings. Humans and mice share many genes, so it was much easier to use strains of genetically identical mice," David Boothman, professor of radiation oncology and pharmacology and associate director of basic research at Case and University Hospitals of Cleveland, said. Soon, you can pick a blood vessel off the shelf (Go To Top) Washington, Oct 23: In a first time study of its kind, American researchers have developed a technique by which tiny blood vessels taken from rats can be implanted in a new animal. The findings could benefit people who have already had vascular bypass surgery and need new blood vessels for subsequent procedures. Previous research has used similar techniques with larger blood vessels, like those used in cardiac bypass surgery. This is the first study to look at these very small blood vessels. Essentially, University of Michigan Health System researchers take these hair-width arterial grafts from a donor rat, remove all living cells from the rest of the tissue, insert vascular cells from the new host and then reimplant the graft. Using the host's own cells increases the likelihood of success by reducing the chance of rejection. "Small blood vessels are needed all the time for grafts to use in heart bypass surgery, lower extremity bypasses and tissue transfer. The biggest problem is finding a source for these vessels. A typical source is some other blood vessel in the patient's body. To be able to have something that we can manufacture ahead of time or be able to take off the shelf, would be advantageous to many patients," says lead researcher David L. Brown, assistant professor in the Division of Plastic Surgery at the U-M Medical School. "You'd expect that the smaller the vessel is, the greater the chance that it would clot. But in our study, the blood vessels stayed open, despite being only 1 millimetre in diametre," says Gregory Borschel, a resident surgeon in the Division of Plastic Surgery at the U-M Medical School. Clotting becomes a problem when reattaching the vessels. "Tissue engineered blood vessels may provide further options for patients who need vascular bypass procedures yet have no suitable donor vessels of their own," says Borschel, who presented his findings Wednesday at the American College of Surgeons 89th Annual Clinical Congress in Chicago. Nitric Oxide study paves way for potent anti-clotting drugs (Go To Top) Washington, Oct 18: Biologists have for long been wondering how nitric oxide (NO) - the molecular messenger that contributes to body functions as wide-ranging as cell death, new blood vessel growth and erections - blocks blood vessel inflammation and prevent clotting. Johns Hopkins University researchers now have the answer. Reporting in the Oct. 17 issue of the journal Cell, cardiologist Charles J Lowenstein and his team observed that NO has the power to inhibit endothelial cells lining blood vessels from releasing inflammatory substances. Normally, these cells activate a process called exocytosis (a release of substances) to start inflammation, releasing packets of molecules into the bloodstream that, like tiny hand grenades, explode and discharge compounds that trigger inflammation. NO can move in and target a protein within the endothelial cells, N- ethylmaleimide-Sensitive Factor (NSF), that stops the process from happening by blocking the ability of NSF to push out the molecules. "Nitric oxide may regulate exocytosis this way in a variety of diseases," says Lowenstein, an associate professor of medicine at Hopkins. "For example, nitric oxide blocks exocytosis from platelets, preventing blood clots; exocytosis from neurons, decreasing neurotoxicity in strokes; and exocystosis from lymphocytes, reducing autoimmune damage." The Hopkins scientists discovered NO's protective role in both cells and mice. They added NO to human endothelial cells in culture and discovered that it blocked the release of inflammatory compounds. The researchers then found that platelets stuck to blood vessels more often in mice that could not make NO, compared to normal mice. The findings already have led Lowenstein's team to develop a novel drug to block exocytosis, thereby acting as an anti- clotting agent. It is a peptide that blocks exocytosis by a mechanism similar to that of nitric oxide. In laboratory tests in mice, the drug prevented tiny, disk-shaped platelets from sticking and causing blood clots. The therapy has potential to limit the amount of heart muscle damage following heart attack, or to treat people with blood-clotting disorders, Lowenstein says, but clinical trials are still years away. Even shorter flights can cause blood clots: Study (Go To Top) London, Oct17: It's not just longer flights that can cause deep vein thrombosis among air passengers. According to an Italian researcher, shorter flights of around two hours are equally bad. Professor Gianni Belcaro screened passengers in the 25-65-year age-group by ultrasound for clots before and after their trip from Stansted, UK, to Italy. Clots were found in 4.3 per cent of high-risk subjects. Two passengers went on to develop pulmonary embolisms. "It shows a risk of developing blood clots even on short flights. The problem can be worsened if travellers are then transferring to a car or coach for a long journey, or if they wait hours in airports," the Sun quoted Belcaro as saying. He recommended passengers to exercise during a trip, drink water and wear flight socks. Meanwhile, experts say that taking 150 mg of aspirin the day before and three days after a flight can also help. Age not a factor in coronary bypass surgery: Study (Go To Top) Washington, Oct 16: If you thought that coronary artery bypass surgery benefits only younger people, then you're wrong. If a study published in the October 15 issue of the Journal of the American College of Cardiology is to be believed, the surgery also improves the quality of life of older people. "Age used to be a more important indicator of the risks and benefits of procedures than it is today," HealthDayNews quoted study author Dr. John Spertus, a professor of medicine at the University of Missouri-Kansas City, as saying. "While older patients did have a slower pace of recovering physical function, relief of (chest pain) was just as brisk as it was for the younger patients and the quality of life improvements were just as much," added Spertus, who's also director of cardiovascular outcomes research at the Mid America Heart Institute of Saint Luke's Hospital in Kansas City. Coronary artery bypass surgery is an invasive procedure in which surgeons take a piece of a healthy blood vessel and use it to make a detour around the blocked portion of a coronary artery. Spertus and his colleagues asked 690 people, 156 of whom were in the 75 and above age-group, undergoing the surgery to complete a questionnaire designed to assess their quality of life and physical functioning before the surgery and a year later. They also asked 224 participants to complete questionnaires monthly for the first six months. It was found that the mortality rate during surgery was just over two percent for the below 75-year group and slightly higher for the group over 75. People over 75 were also more likely to die in the year following surgery - 11.5 percent as compared to 5.4 percent for the younger patients. But, when it came to symptom relief, the older group fared just as well as the younger group. As Spertus puts it: "There's a sense that doing a very invasive, open procedure like bypass surgery on older patients subjects them to a lot of risk and potential pain, so one would want to be sure that there were benefits to offset the risk. "What we found was that compared to younger patients, older patients got just as much benefit in terms of quality of life," he added. Fashionable contact lenses can cause blindness: Expert (Go To Top) Washington, Oct 14: If you are planning to buy cosmetic contact lenses that change the colour or the appearance of your eyes with designs, then beware! According to Dr. H. Dwight Cavanagh, vice chairman of ophthalmology at University of Texas South-western Medical Centre at Dallas and editor-in-chief of the scientific journal, Eye and Contact Lens, using such lenses without a doctor's prescription or monitoring can damage the eyes and even cause blindness. "Letting an underage member of the family use these lenses without supervision is like giving them the car keys without a licence and without an adult in the front seat. By purchasing contact lenses over the counter, you would abrogate every single safety guarantee in place," he says. "Remember, a lot of permanent damage can be done after only a few hours of wear," adds Cavanagh. According to him, ill-fitting over-the-counter contact lenses rub a patient's cornea, causing infection and damage that could lead to blindness. The lenses could also cause irreversible scarring, inflammation and even loss of the eye. However, when a patient is prescribed contact lenses - regardless of whether the lenses are worn to correct vision - an ophthalmologist or optometrist examines the eye to make sure lenses don't aggravate existing problems. They measure the eye to ensure the best possible fit and teach the patient how to handle the lenses properly and how to keep them sterile. The doctor will monitor the patient to make sure problems don't develop later. "If you want blue or orange or yellow eyes, you can have it. Just go to a licensed professional to get them," says Cavanagh. While the risk for corneal ulcers among prescription contact lens users is one in 2,500 for daily wear and one in 500 if patients sleep in the lenses. The risks are much higher in over-the- counter contact lenses because none of the regular safety procedures are followed, he says. Science Bone broken? New surgery will give you a `natural one' (Go To Top) Washington, June 14: A new method of treating broken or crushed bones will, it is believed, do away with the requirement of processes like bone grafting and amputation. This may facilitate the way for a bone to grow on its own, thereby leaving the patient with "natural bone". Mulligan's company has invented a technique that might lead to a revolution as far as bone surgeries are concerned. It goes this way. If, for instance, the humerus bone in the arm is injured and damaged, a CT scan or MRI image can be made of the good arm bone and converted to a "growth code" - a 3-D virtual image - of the replacement bone segment needed. Using that data, the rapid prototyping technology then creates a micro-porous calcium phosphate coated polymer `bone' which is then surgically implanted into the arm where the damaged bone has been removed. The calcium phosphate coating is very thin and allows the bone cells to attach themselves to the implant. Growth factors could be added to the calcium phosphate to encourage the bone growth at faster rates. Those who found the new surgery technique say what is left of the real bone attaches itself to the polymer bone after about eight weeks. Then the real bone begins to `grow through' the porous frame. As it does, it `eats' the frame and the body naturally excretes the calcium phosphate material. In about 18 months, the bone is expected to find full shape, leaving the patient with "natural bone." -ANI |
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