health ‘ sci briefs

(MCT) SEATTLE – Dreary northern winters are infamous for inducing depression. But being… (MCT) SEATTLE – Dreary northern winters are infamous for inducing depression. But being starved for sunlight can do more than kick you into a psychic hole.

A growing body of evidence suggests it can raise your risk of cancer, increase susceptibility to heart attack, diabetes and other disorders and at least partly account for the region’s sky-high rates of multiple sclerosis.

The reason is vitamin D, an essential nutrient produced in abundance by skin exposed to the sun’s rays. Long dismissed as being important mainly for strong bones, the so-called sunshine vitamin is now recognized as a key player throughout the body, including the immune system.

Experts say vitamin D deficiency is much more common than previously believed -especially in northern climates, where solar radiation from October to March is too puny to maintain healthy levels.

“You’re in a dark, gloomy place,” said Bruce Hollis, a leading vitamin D researcher at the Medical University of South Carolina. “In the winter, you could stand outside naked for five hours and nothing is going to happen.”

Increased use of sunscreen has turned a seasonal shortfall into a year-round condition for many people. A recent survey in Britain found 87 percent of adults tested during winter and more than 60 percent in summer had sub-par vitamin D levels. Doctors in many parts of the world, including California, report a resurgence of childhood rickets, soft bones caused by lack of vitamin D.

While supplements offer a cheap and easy solution, Hollis and other researchers argue the recommended intake is too low to provide many health benefits. A Canadian medical organization advises that pregnant and nursing women take 10 times the amount suggested in the United States.

“You’re more likely to live longer and you’re less likely to die of serious chronic disease if you have adequate vitamin D on board,” said Michael Holick of Boston University School of Medicine, one of the world’s top experts. “It may well be the most important nutrient of the decade.” -By Sandi Doughton, The Seattle Times

(MCT) PHILADELPHIA – For the first time, researchers have slowed and possibly stopped the AIDS virus from reproducing in patients by using a gene therapy that tricks it into self-destructing.

The results, announced Wednesday, are heartening not just for people infected with HIV but also for the field of gene therapy, which remains highly experimental more than 20 years after scientists figured out how to use viruses to insert therapeutic genes into a cell’s genome.

Mostly, the results are a big step forward for the biotech start-up that is developing the novel therapy and for its collaborators at the University of Pennsylvania.

“The buzzword in the field is viral ‘fitness,’ meaning how well the virus can replicate,” said Gary McGarrity, executive vice president for scientific affairs at Virxsys Corp., in Gaithersburg, Md.

“In eight of the nine patient samples we studied, we see diminished HIV fitness up to two years after treatment.”

That raises the hope that even if medical science cannot come up with the Holy Grail of AIDS research – a vaccine to prevent HIV infection – patients may be able to keep HIV under control, perhaps without relying on the toxic drug cocktails that commuted what was once a death sentence.

“I think the Virxsys report is very important,” said John Rossi, a molecular biologist at the City of Hope in California, who is also working on a gene therapy treatment for HIV.

“A lot of HIV patients are over 60 now and they’re suffering the consequences of these toxic drugs. This shows there are alternatives.” -By Marie McCullough, The Philadelphia Inquirer

(MCT) WASHINGTON – Like the rumble of distant thunder, bird flu continues to spread across Asia, Africa and Europe. Although it’s been out of the news lately in the United States, scientists say that avian influenza, as it’s also known, remains a serious threat to human and animal health.

The lethal H5N1 version of the virus is mutating rapidly and rampaging through bird flocks throughout those parts of the world, infecting and often killing people who come in contact with them.

The fear is that the virus will change into a form that makes human-to-human transmission quick and easy. At least seven slightly different subtypes already have been identified.

“New genes are being formed all the time,” said Henry Niman, a molecular geneticist who tracks bird-flu outbreaks around the world.

Although H5N1 hasn’t reached the Western Hemisphere, Joseph Domenech, the chief veterinary officer for the United Nations Food and Agriculture Organization, warned last month that it “could still trigger a human influenza pandemic.” A pandemic is a worldwide outbreak such as the 1918 Spanish flu, which killed tens of millions of people in the United States and Europe.

The virus “continues to cause human disease with high mortality and to pose the threat of a pandemic,” the latest situation report from the World Health Organization says.

As of Wednesday, bird flu had infected 362 people and killed 228 of them in 14 countries in Asia, Africa and Europe.

In the last year, the WHO confirmed 98 new human cases, including 69 deaths, an alarming 70 percent death rate. It was the second worst year for bird flu, topped only by 2006, when 115 cases and 79 deaths (69 percent) were reported.

Since the major outbreak in China in 2003, the virus has killed millions of chickens, ducks and geese along with pigs, cats and other mammals in some 50 countries.

Almost all the people who’ve been infected caught the disease from close contact with domestic poultry and occasionally from wild ducks, geese or swans. In a handful of cases, scientists think the virus passed from one human to another, usually among relatives or people living close together. -By Robert S. Boyd, McClatchy Newspapers