Gene therapy slows down cognitive decline
PARIS
An experimental treatment for Alzheimer disease where genetically modified tissue is surgically inserted into the patient's brain appears to reduce the rate of cognitive decline, according to preliminary results of a study published in Nature Medicine.
In the first-ever gene therapy for Alzheimer, the study by researchers at the University of California in San Diego found that the rate of disease progression seemed to be reduced by 36 to 51 percent for a mean period of nearly two years using two common measures of cognitive function.
In the six to 18 months immediately following the treatment, cognition apparently improved or stabilized in five of the six subjects who completed the therapy, the study said. Current approved medications for treating Alzheimer have an estimated impact on these cognitive measures of five percent, and are not known to affect decline over prolonged periods.
"If validated in further clinical trials, this would represent a substantially more effective therapy than current treatments for Alzheimer disease," said Mark Tuszynski, principal investigator.
The study, however, did not include a comparative placebo group, and researchers cautioned that the preliminary results were only for the phase-I trial and more clinical tests were needed.
Potential "potent" treatment for Alzheimer
CHICAGO
Researchers in Chicago have conducted experiments that they say could lead to a breakthrough in the treatment of
Alzheimer disease. The experiments involving mice have been successful in both preventing and reversing the development of Alzheimer's plaque in the brain. "I think this is a very potent treatment for Alzheimer," said lead researcher Terry Lichtor, an associate professor at Rush University Medical Center. Lichter presented the findings at the annual meeting of the American Association of Neurological Surgeons in April.
Lichtor's group found that by injecting the brains of mice with antibodies, they could prevent the early onset of Alzheimer. His most recent study looked at the impact of injections on mice in the later stages of Alzheimer.
"In this study I showed I could reverse it quite dramatically," he said. "We got about a 70-percent plaque reduction. Is that enough to cure them? It's a pretty good start."
Lichtor said he is now ready to begin the application process to launch a clinical trial. Should the clinical trial be successful, the treatment could become widely available within four to five years.
Around 4.5 million Americans currently suffer from Alzheimer, estimated to grow to 16 million by 2050.
The experiment improves upon earlier studies that had to be halted during clinical trials because patients developed inflammation in their blood vessels. By injecting antibodies directly into the brain, Lichtor said his group was able to avoid inflammation.
Preventive treatment for malaria shows promise
PARIS
A standard antimalaria drug administered to African infants in their first months of life protected many of them against the disease, according to an innovative trial that monitored them until age two.
Around 700 children in Tanzania were enrolled in the scheme, in which they were given sulfadoxine-pyrimethamine three times, when they were given other vaccinations at two, three, and nine months of age. In the first year, prevalence of malaria among this group was 59-percent lower than among infants who had not received the drug. By the end of the second year, the rate was 36-percent lower.
In another study, also published in The Lancet, London doctors suggest a combination of two drugs--artemether and lumefantrine--are an effective way of combating malaria in areas of Africa where resistance to frontline drugs is high. Plasmodium falciparum, the mosquito-borne parasite that causes malaria, is resistant to the antimalaria drug chloroquine in nearly every area where the disease is rife.
Ageing father boosts risk of miscarriage
PARIS
The father's age, like the age of the mother, plays a major role in the risk of miscarriage, according to a study, which suggests that the danger increases by nearly a third among men aged over 35.
The research in the American Journal of Epidemiology draws on background details from 5,000 Californian women who enrolled in a study in the 1990s that assessed pregnancy outcome. "Among men who are older than 35, the risk of a miscarriage increases by around 30 percent, regardless of the woman's age. Overall, the risk doubles from the age of 20 to 50," said lead researcher Remy Slama of France's National Institute for Health and Medical Research (Inserm).
The cause lies in the higher probability of chromosomal damage in sperm as a man gets older, said Slama. The flawed DNA causes the fetus to develop abnormally and be aborted.
Among the miscarriages recorded in the 1990s study, 20 percent could be attributed to the age of the father.
Previous research has already highlighted the mother's age as a risk factor for miscarriage. A woman aged 40 is three times likelier to miscarry than a woman aged 25.
Women twice as likely as men to suffer sleepless nights
PARIS
Women are around twice as likely as men to suffer insomnia, although the more educated a woman is, the better her chances of sleeping through the night. The findings are based on a Taiwanese survey of nearly 40,000 men and women aged 15 and older.
Among both sexes, insomnia was more common among people who were older, divorced or separated, had low income, were unemployed, were in poor health, or had children living at home. Among women, a higher level of education was linked with better quality of sleep, but the reverse was true among men.
One likely factor that keeps women awake at night is biological, such as the effects of the menopause or menstrual cycle on physical comfort, the authors say. But other causes could be sociological, such as the fatigue and anxiety of shouldering more of the burden of housekeeping and child-rearing than men, and the poor recognition given to this work.
The paper by Chen Ying-Yeh of the Taipei City Psychiatric Center, appears in the Journal of Epidemiology and Community Health.
Antinicotine vaccine could help smokers
ORLANDO, Florida
An experimental antinicotine vaccine has shown encouraging results in helping smokers kick the habit. Almost 60 percent of the 341 smokers who took the vaccine stopped smoking for at least six months, said Jacques Cornuz, a Swiss researcher who led the vaccine study. Cornuz, of the Centre Hospitalier Universitaire Vaudois in Lausanne, Switzerland, presented the results at the 2005 annual conference of the American Society of Clinical Oncology (ASCO). He said a third of those who developed lower levels of antibodies stopped smoking, about the same as those who received placebo.
The vaccine, developed by Cytos Biotechnology of Zurich, is based on a bacteriophage virus, which attacks bacteria. The bacteriophage in the vaccine neutralizes the nicotine before it can stimulate the brain.
Exposure to pollution increases risk of heart attack
STOCKHOLM
Long-term exposure to high levels of air pollution greatly increases the risk of suffering a heart attack, according to a new Swedish study.
"We have found that if you live in an area with high emission levels, your chances of having a heart attack could be as much as 50-percent higher compared to people who live in places with very low emission levels," said Mats Rosenlund, an associate professor at the Karolinska Institute in Stockholm who headed the study.
The "environmental factors in cardiovascular disease" study, a countrywide case-control study, involved 2,246 cases of myocardial infarction and 3,206 population controls between 1992 and 1994.
"We have taken into consideration factors like smoking and diet to show air pollution's role" in provoking heart attacks, Rosenlund said, pointing out, however, that noise pollution may also have been a contributing factor. The study also concluded that passive smoking "clearly increases the risk of heart attack," Rosenlund said. He added, however, that people who had been exposed to passive smoke at home or at work but who changed their environment, appeared to return to normal risk levels within six to seven years.
A separate part of the study, based on a poll of 15,000 Swedes in 1997, concluded that living near an airport can dramatically increase the chance of high blood pressure. "There is a fairly strong connection between living close to an airport and high blood pressure. The closer people live to Arlanda (Stockholm's airport), the more likely it was for them to suffer from high blood pressure," Rosenlund said.
Parkinson linked to pesticide
PARIS
Fears that pesticides may cause Parkinson disease have been strengthened by research that says the greater the exposure to these chemicals, the higher the risk of developing the disease, New Scientist reports. Low users of pesticides such as amateur gardeners are nine percent likelier than nonusers to develop Parkinson, while high users, such as farmers, are 43 percent likelier, the study says.
The so-called Geoparkinson study, head-authored by University of Aberdeen scientist Anthony Seaton, investigated the background of 767 volunteers in Scotland, Italy, Sweden, Romania, and Malta who had Parkinson's disease. These were compared against 1,989 controls--people who had similar backgrounds but were healthy.
The study does not identify which pesticides could be to blame, and says there are other risk factors for Parkinson that are much higher. For instance, having a family history of the disease boosts the risk by 350 percent; being knocked unconscious raises the risk by 32 percent; and those who have been knocked out several times face an increased risk of 174 percent.
Vitamin E may fend it off
PARIS
Diets rich in vitamin E may offer protection against Parkinson, a study in Lancet Neurology suggests. People who had moderate to high amounts of vitamin E in their diets were less likely to develop Parkinson, while vitamin C and beta carotene seemed to have no effect, it says. But pills and other supplements of vitamin E--as opposed to vitamin E that occurs naturally in food--may not have this protective effect.
The paper is a metaanalysis of previous studies on Parkinson and nutrition. Its authors trawled through two big databases to find eight research projects in this area, spanning 1966 to March 2005. They found that people who had a pronounced intake of vitamin E in their diets were 19-percent less likely to develop Parkinson.
The authors, led by Mahyar Etminan of the Royal Victoria Hospital and McGill University in Montreal, Canada, suggest that vitamin E may be more effective in naturally occurring form rather than as a supplement because it is a slightly different molecule that is more "bioactive" than its synthetic counterpart. As to why vitamin C--a highly powerful antioxidant--does not appear to combat the risk of Parkinson, the authors suggest that the molecule may get filtered out by barriers to the brain, diminishing its "neuroprotective potential." They, however, warn that before doctors recommend any shift in diets, the results would have to be confirmed by a large trial to compare the outcome of matched people who have different levels of dietary vitamin E and are then monitored to see whether they develop the disease.
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