Growing a Spare
World-first process uses abdominal cavity to grow replacement organs and veins from bone-marrow cells
Less stress, more exercise helps heart
WASHINGTON
Stress management and exercise can reduce the threat of heart attacks in people with cardiovascular disease.
Researchers tested 134 men and women ages 40 to 84 suffering from coronary-artery disease to see how regular exercise and techniques to reduce stress would affect their illness. Over 16 weeks, they were grouped into those receiving routine medical treatment, those with treatment and an exercise regime, and a third group that practiced stress management in addition to exercising. All were given stress tests, including making challenging public speeches before critical judges and tracing difficult figures from a mirror reflection.
Researchers found within the third group, which underwent 90 minutes of stress management training a week, a significant reduction in key risk indicators for cardiovascular problems compared with the others. Those who exercised also showed better indicators than those who received only routine medical treatment.
"Results of this randomized, controlled trial demonstrate that behavioral treatments provide added benefits to routine medical management in patients" with stable coronary-artery disease, said study leader James Blumenthal of Duke University Medical Center in North Carolina.
The study was published by the Journal of the American Medical Association.
One-meter waistline is guide to diabetes, heart risk
PARIS
People with a waistline of one meter (39.3 inches) or more are at serious risk of insulin resistance, a precursor to diabetes and heart disease, according to a study published in the British Medical Journal.
The guideline is suggested by researchers in Sweden who compared girth with biological markers that predict insulin sensitivity among 2,700 adult volunteers of various ages and body shapes.
"A waist circumference of less than 100 centimeters (39 inches) excludes insulin resistance in both sexes," said the study, led by Hans Wahrenberg, associate professor at Stockholm's Karolinska University Hospital.
The one-meter measurement is a handy replacement for more complex arithmetic--such as body-mass index and the waist-hip ratio--that is sometimes used as a predictor of insulin resistance.
Insulin deficiency can lead to heart and blood disorders that are responsible for 50 to 80 percent of the deaths that occur among diabetics.
People with severe forms of the disease can also suffer from blindness, loss of limbs and kidney failure.
Insulin resistance is the cause of type 2 diabetes, which accounts for about 90 percent of all cases of this disease and usually shows up in adults aged 40 or above. Incidence of type 2 diabetes has rocketed alongside rates of obesity, triggered by consumption of sweet and fatty foods and a sedentary lifestyle.
Gene injection triggers growth of new blood vessels
JERUSALEM
Medics in Israel have performed the first operation to inject genes into a cardiac patient, stimulating the growth of new blood vessels. The new blood vessels improved the flow of blood to the unnamed 68-year-old patient's heart, allowing such a rapid recovery that he was released from hospital on the day after the operation.
The injection was administered through a catheter and the patient remained conscious throughout and suffered no pain. "This experiment marks a major breakthrough in the field of genetics and catheterization," said Ran Kornowski, a cardiac specialist from the Rabin Medical Center. "We believe and hope that this revolutionary, innovative research will lead to a major breakthrough in the field of gene transplantation for the treatment of cardiac patients."
Australian researchers grow spare body parts
SYDNEY
Australian researchers unveiled a pioneering procedure that they said will allow the body to grow some of its own spare parts and help prolong lives, notably for kidney patients. The world-first process uses a patient's abdominal cavity as a kind of "bioreactor" to grow replacement organs and veins from cells derived from bone marrow.
The University of Queensland researchers have already grown new tissue in the body cavities of rats and dogs and then used it to replace diseased tissue without the problems of organ rejection and infection.
Clinical trials are due to begin soon of the procedure, developed by husband and wife team Julie and Gordon Campbell. Julie Campbell said the process uses the body's natural reaction to foreign objects-an inflammatory response in which any item inserted into a body cavity becomes encapsulated in bone-marrow cells many layers thick. She said the process took only two or three weeks, after which the foreign object was removed and the tissue harvested.
"The type of organs which we can grow are not your kidney, not your heart, not your brain, but organs that have smooth-muscle-cell walls, like an artery, a vein, a uterus, or a bladder," she said. "It's a bit like putting a piece of sand into a pearl oyster and the encapsulation of cells is just like a pearl being formed around that grain of sand."
Doctors said the procedure offers new hope for replacing blocked or damaged blood vessels, and could help people who require dialysis treatment due to kidney disease.
Australians report breakthrough in battle against malaria
SYDNEY
Australian scientists have reported a breakthrough in efforts to understand how malaria parasites attack the body, a discovery that could save millions of lives. A six-year research project at Melbourne's Walter and Eliza Hall Institute has uncovered how the parasite Plasmodium falciparum disguises itself to avoid detection by the human immune system.
Scientists have known since 1996 that the malaria parasite hides from the immune system by depositing a protein on the surface of infected red blood cells that effectively make them invisible to the body's disease-fighting mechanism. The Australian team led by molecular biologists Alan Cowman and Brendan Crabb say the research is the first to unravel how the masking system works. It found that the parasite uses 60 different protein-masking systems in a deadly game of hide and seek. As soon as the immune system learns to recognize one protein and starts making antibodies against it, the bug switches to another form of the protein.
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Cowman said that while the parasite used one mask, known as a var gene, it kept the other 59 invisible to the human body's immune system by wrapping them in bundles. He said the discovery gave scientists a new understanding of how the parasite works and opened up avenues of research on how to interrupt the process so the body's immune system could defeat the disease.
"If you could work out a way of causing the parasite to switch all the var genes on, then the body would see all the variations of var genes, and the immune system would be able to control the infection," Cowman said. He said researchers still had a lot of work to do on better understanding exactly how the var genes are activated so that drugs could be developed to interfere with the process.
Pneumonia vaccine could slash child mortality
PARIS
A vaccine tested in Gambia could save the lives of hundreds of thousands of poor children at risk for pneumonia, according to a study published in March in The Lancet.
The vaccine was 77-percent effective in preventing infections caused by the pneumococcal bacterium, which causes a dangerous form of pneumonia as well as meningitis and septicemia. Cases of pneumonia as confirmed by chest X-ray fell by 37 percent among vaccinated children, and incidence of meningitis and septicemia plummeted by half. Mortality from these diseases fell by 16 percent. The World Health Organization said the results held out great promise.
The pneumococcal conjugate vaccine made by Wyeth was previously tested in the United States. It was tested in Gambia among 17,437 children who either received the vaccine or a placebo to see how effective it could be in the setting of a country where medical resources are scarce.
Superbug hits 42 patients at Singapore hospital
SINGAPORE
Vancomycin-resistant enterococci (VRE) have been detected in 42 patients at the Singapore General Hospital. Of the 42, only one is an infected patient; the rest are carriers.
According to a hospital spokeswoman, there have been no fatal cases of VRE and no medical treatment is required unless a patient has been infected with the bacteria. Patients infected by VRE
To contain the spread of the bacteria, the hospital is continuing to screen all its inpatients for VRE, which is spread by touching infected areas or items contaminated by the bacteria.
Traffic fumes linked to DNA damage
PARIS
Traffic fumes can damage DNA, according to a study published in March in Occupational and Environmental Medicine.
Researchers led by Lai Ching-Huang of Taiwan's National Defense Medical Center took blood and urine samples from 47 workers at the First Highway toll station located 10 kilometers from Taipei. The samples were compared with those from a reference group comprising 27 female office workers.
The toll workers had nearly twice the urine levels of a chemical called 8-OHdG, a marker of DNA damage inflicted by free radicals. In parallel with that, they also had higher levels in their blood of 1-OHP, a metabolic byproduct from inhaling exhaust gases. Free radicals are blamed for causing cell mutation, cancer, and ageing.
Cloned cattle produce normal milk, beef
WASHINGTON
Beef and milk from cloned cattle are similar to those produced by normal animals, according to a Japanese-US study published by the Annals of the American Academy of Sciences, the first to investigate the nutritional value and possible health risks of products from animal clones. "We conclude that most parameters of the composition of the meat and milk from somatic animal clones were not significantly different from those of their genetically matched comparators or industry breed comparators," said Xiangzhong Yang, head biologist from the Center for Regenerative Biology at the University of Connecticut, who took part in the study. "All parameters examined in this study were within the normal range of beef and dairy products approved for human consumption," he said.
The Food and Drug Administration has not authorized the sale of beef and dairy products from animal clones in the United States after it publicly raised concerns in 2003 on the possible health risks of such products.
In 2002, the American Academy of Sciences concluded that products from cloned animals should not pose health risks to humans, although it noted the few studies conducted on the matter.
Researchers from the University of Connecticut and the Kagoshima Reproductive Institute of Japan analyzed and compared around 100 parameters such as proteins, fat density, antibodies, and lactose in more than 1,000 samples of meat and milk from cloned and normal animals. The cloned milk came from four clones of a 13-year-old Holstein cow, while the cloned beef came from two clones of a 17-year-old Japanese "black bull."
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