Health Highlights: May 27, 2008

HealthDay SHARE
  • Sodium Nitrite Stimulates Blood Vessel Growth
  • Evolving Bird Flu Viruses May Pose Pandemic Threat
  • Warm Weather Workouts Require Common-Sense Precautions
  • Poll: Wounded Iraq Soldiers Get Substandard Care From VA
  • Caressing Preemies May Help With Pain of Medical Procedures
  • New York City Man Dies After Taking Aphrodisiac From Toad Venom

Here are some of the latest health and medical news developments, compiled by editors of HealthDay:

Sodium Nitrite Stimulates Blood Vessel Growth

Daily injections of sodium nitrite stimulated the growth of new blood vessels and restored blood flow to tissues damaged by simulated vascular disease in just three to seven days, a new U.S. study found.

Researchers induced ischemia (reduced blood flow) in the hind legs of mice by tying off the rodents' femoral arteries. The mice then received twice-a-day injections of low-dose sodium nitrite, Agence France-Presse reported.

Within three days, the animals' hind legs were showing signs of new blood vessel growth (angiogenesis). Within seven days, the blood supply in their hind legs was almost back to normal. In a group of mice that received no treatment, it took 28 days for circulation in their hind legs to return to normal.

Ischemia occurs in people with conditions such as peripheral artery disease and diabetes.

"The treatment has tremendous potential for stimulating angiogenesis to alleviate the discomfort caused by ischemia, and at the dosages we used, sodium nitrite is safe and far below any toxicity threshold," said Christopher Kevil, an associate professor of pathology at Louisiana State University Health Science Center in Shreveport, AFP reported.

"Moreover, our work suggests that sodium nitrite therapy could be beneficial for stimulating angiogenesis and tissue healing after ischemic events seen in stroke and heart attacks," Kevil said.

The study appears in the journal Proceedings of the National Academy of Sciences.


Evolving Bird Flu Viruses May Pose Pandemic Threat

U.S. researchers have identified certain strains of bird flu that appear to be moving closer to developing traits that could trigger a human pandemic.

They found that a few of the H7 virus strains that caused minor, non-transmissible infections among people in North America between 2002 and 2004 may be evolving the same human tracheal cell sugar-binding properties seen in flu viruses that caused global pandemics in 1918, 1957 and 1968, Agence France-Presse reported.

"These findings suggest that the H7 class of viruses are partially adapted to recognize the receptors that are preferred by the human influenza virus," said Terrence Tumpey, a senior microbiologist with the U.S. Centers for Disease Control and Prevention.

If these H7 viruses continue this type of evolution, they may be able to pass more easily between animals and people, said the researchers, who called for strict surveillance of avian flu viruses, AFP reported.

The study appears in the journal Proceedings of the National Academy of Sciences.


Warm Weather Workouts Require Common-Sense Precautions

Memorial Day is considered the unofficial start of summer, and that means more people will be heading outdoors to pursue favorite exercises and physical activities.

With that in mind, the American College of Sports Medicine, the American Medical Association and more than 50 supporting organizations, including the National Athletic Trainers' Association, have launched the "Exercise is Medicine" initiative. It includes a list of tips that people of all ages can follow to enjoy physical activity and exercise while reducing the risk of "exertional heat illness."

"Many cases of heat illness are preventable and can be successfully treated if such conditions are properly recognized and appropriate care is provided in a timely manner," said certified athletic trainer Brendon McDermott, of the University of Connecticut. "We're hoping to educate athletes, coaches, parents and health-care providers about what can be done to prevent and treat heat illnesses."

To guard against heat illnesses, the trainers' association recommends the following steps:

  • Gradually increase activity in terms of intensity and duration in the heat. This prepares your body for more intense, longer duration exercise in warm conditions, and helps prevent injury and heat illness.
  • Mix in periods of rest during activity and assure adequate rest between exercise bouts. Rest breaks are an important defense against heat illness, and proper sleeping habits decrease your risk as well.
  • Begin outdoor activities only after you're properly hydrated. Drink water or sports drinks throughout physical activity in the heat.
  • A darker urine color is a quick sign of dehydration. Your urine should look more like lemonade than apple juice.
  • Exercise during cooler portions of the day -- early morning or late evening, if possible.
  • Don't participate in intense exercise if you show signs of an existing illness, such as fever, diarrhea or extreme fatigue. These can decrease your body's tolerance for heat and increase your risk of a heat illness.