 Hope for Multiple Sclerosis Patients
Pioneering human trial shows statins appear to halt lesions
RISKY CLONING CHEMICAL
SANTIAGO, Chile
Researchers at the University of Chile have warned the scientific community that the use of a certain chemical compound in the cloning of animal and human embryos could cause mutation.
Chilean scientist Ruby Valdivia and Japanese professor Motoe Kato issued the alert after a bacteria cloned in a university laboratory with the chemical 6-DMAP (6-dimethylaminopurine) was found to have mutated.
"We are issuing an alert, because there could be a risk if this chemical is used in human experiments, because it has a mutating effect," Valdivia said.
The Chilean researchers said 6-DMAP, which is used to stimulate DNA in a cloned cell, should not be used in experiments with human embryos. "From our results, it can be concluded that there exists a high probability of mutation during the cloning process using this compound," Valdivia said.
The chemical is being used by scientists who are studying cloning on mammals in the laboratory of Dr. Woo Suk Hwang in South Korea. The lab has produced cloned pigs, cats, sheep, and cattle. It is the same South Korean lab where researchers using 6-DMAP have cloned human embryos, the journal Science reported in February.
The Chilean scientists said a bioanalysis center in Tokyo substantiated their findings.
STATINS SHOW PROMISE FOR MULTIPLE SCLEROSIS
PARIS
The first tests of cholesterol-busting drugs on people with multiple sclerosis (MS) have yielded encouraging results. The trial, although only small-scale, has been eagerly awaited. Doctors around the world have been hoping the outcome will confirm lab evidence using cell samples and mice that statins appear to halt MS.
MS is a slowly progressive inflammatory disease of the brain and central nervous system in which the body's immune system attacks a fatty insulative sheath around nerve fibers. The symptoms range from numbness and tingling to muscle weakness and spasms, cramps, nausea, depression and memory loss. In the worst cases, patients are unable even to swallow or breathe properly.
Inderjit Singh of the Medical University of South Carolina and colleagues recruited 30 people aged 18 to 55 with a "relapsing-remitting" form of MS. People with this condition suffer from new symptoms of the disease, while old symptoms can reemerge and get worse.
The 30, who later fell to 28 after two patients dropped out, were each given an 80mg dose of oral simvastatin for six months and underwent magnetic resonance imaging (MRI) to monitor lesions on their brain. By the end, the number and size of these lesions fell by 44 percent compared with pretreatment.
None of the patients had any side effects from the statins, according to the study, published in The Lancet.
Singh's team believes that the statins work because they inhibit part of the inflammatory process that causes the lesions. Previous research had suggested that statins prevent accumulation of leucocytes, one of the front-line troops in the immune system.
In an independent review, Dutch expert Chris Polman of the VU Medical Center in Amsterdam said the findings marked "a big step forward" by confirming the experimental interest in statins for tackling MS. "But it is only a first step."
He noted that only a small number of volunteers were involved in the trial and that there was no "control" group to vet whether the results may have been skewed by psychological or other factors. The next step has to be a large-scale trial with volunteers chosen randomly and assigned either to treatment or control group, he said.
Polman said doctors, patients, and drug companies had to work urgently to see whether statins were effective and safe, and if so, how the drugs could be used properly. Without that knowledge, the door would be flung open to cowboy treatment-doctors who prescribe the statins for a desperate patient. This would be a "dangerous boomerang," warned Polman.
Statins have created much excitement in the world of MS treatment not just because of the hope that they could be effective. As an oral medication, they would be far less troublesome as a treatment option than injections. In addition, they are cheap and widely tolerated by patients.
DIABETES RAISES ALZHEIMER'S RISK
WASHINGTON
The risk of developing Alzheimer's disease (AD) increases by 65 percent among people aged 65 or older who suffer from diabetes, according to a study published in the May issue of the Archives of Neurology.
Researchers studied 824 Catholic nuns, priests, and monks for five years and six months. Within this group, 151 people developed Alzheimer's disease, including 31 who were diabetic, leading the researchers to conclude that the risk increases by 65 percent for older people with diabetes mellitus.
"The research on a possible link between diabetes and increased risk of AD is intriguing, and this study gives us important additional insights," said Neil Buckholtz of the National Institute on Ageing, which is part of the National Institutes of Health. "Further research, some currently underway, will tell us whether therapies for diabetes may in fact play a role in lowering risk of AD or cognitive decline," he said.
The study was led by Dr. Zoe Arvanitakis and Dr. David Bennett of the Rush University Medical Center in Chicago.
BREAST IS BEST FOR THE HEART, TOO
PARIS
The first major long-term assessment of the cardiovascular benefits of breast-feeding says mother's milk helps curb the fatty proteins that contribute to heart problems.
British investigators measured the cholesterol levels of 216 teenagers aged 13 to 16 who, in their infant years, had taken part in a trial involving more than 900 babies who had been given either milk formula or breast milk. Those who had been breastfed had a 14-percent lower ratio of "bad" to "good" cholesterol in their blood compared with those who had been given infant formula. This group also had lower concentrations of C-reactive protein (CRP), deemed a herald of future clogged arteries.
"Infant nutrition permanently affects the lipoprotein profile later in life," proposes lead researcher Atul Singhal of London's Institute of Child Health. "Our findings suggest that breast-milk feeding has a major beneficial effect on long-term cardiovascular health."
Singhal says the study, which appears in The Lancet, is sufficiently wide in numbers, scope, and duration to draw a clear conclusion about the benefits.
Last November, an overview published in the British Medical Journal of the effects of breast-feeding on adult blood pressure said the claims of benefit were unfounded. It said that published studies had been based on small numbers of volunteers, which exposed the findings to the risk of statistical bias.
SARS VIRUS MAY SPREAD VIA SWEAT, FOOD, SEWAGE, TOUCH
PARIS
The SARS virus has been found in sweat glands and the intestine, according to a new study, which says that in theory the disease may spread via contaminated sewage, food or even a handshake, not just by airborne droplets.
Pathologists from the First Military Medical University in Guangzhou in southern China warn that if further research proves that SARS can be transmitted by these unexpected routes, the implications for public health are major.
The team devised two methods of testing for the presence of the coronavirus (SARS-CoV) that causes the disease. One was an antibody that binds specifically to the virus, and the other was amplification of telltale fragments of viral DNA.
Using these two markers, they tested tissue taken from four people who had died of SARS, and from four "controls," people who had died of other causes. The results were remarkable, according to their study published in the Journal of Pathology.
As expected, they found the lungs of SARS victims to be riddled with the virus. Up to 49 percent of the tissue cells they viewed had been infected. This is unsurprising because SARS is already known to be a disease that can be carried by droplets expelled in sneezes and coughs, its prime target area is the airways, and its symptoms are akin to pneumonia.
"Strikingly," the authors add, "SARS-CoV was also detected in many other organs and tissues, including stomach, small intestine, distal convoluted renal tubule, sweat gland, parathyroid, pituitary, pancreas, adrenal, liver, and cerebrum." Viral infection in the small intestine and renal system reached 25 to 49 percent of cells, and the same figure was seen for the skin. In the liver, pancreas, and brain, 24 percent or less of cells were infected.
Lead researcher Ding Yangqing said that, like the respiratory tract, the gastrointestinal system could be "a primary target" for the virus. "This suggests that the gastrointestinal system may also be an entry route for SARS-CoV [if it is] present in food or water," he said. "Although there is no report of such transmission, caution should be exercised by the at-risk population during the SARS-CoV endemic season. This finding supports the hypothesis that SARS-CoV may be released into the environment via feces from individuals [with the disease]."
As viral traces were found in the kidneys, urine may also theoretically transmit the disease.
Yangqing also noted that the virus had, for the first time, been found in sweat gland cells in the skin, suggesting, "Another route of transmission, since this virus may be excreted in sweat and infect other people who are in direct contact with the patient's skin."
The repercussions for public health may be far-reaching, the study warns. If, for instance, skin contact is confirmed as a transmission route, it would mean that SARS patients may have to wear gloves, disposable gowns, and eye goggles, in addition to a full N95 face mask, and avoid kissing or touching other people.
SEASONAL CHOLESTEROL
WASHINGTON
Cholesterol levels among people vary with the seasons and peak during winter months, according to a US study published in the Archives of Internal Medicine. Researchers studied 517 healthy people in the northeastern state of Massachusetts whose cholesterol levels were monitored every three months for a year. They recorded the participants' eating habits, physical activity, and exposure to light.
Cholesterol among the men increased by an average of 3.9 milligrams per deciliter of blood, peaking in December. It increased by an average of 5.4 milligrams among women, whose cholesterol peaked in January.
People who started off with high cholesterol levels experienced higher increases. In the group, the men's cholesterol level averaged 222 milligrams, while the average was 213 for women.
"The information provided by this study could assist in the continuous development of guidelines for the treatment of hypercholesterolemia; however, we do not believe that season-specific guidelines would be justified," the study said.
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