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vCJD in Hong Kong
A Chinese woman is confirmed to have variant Creutzfeldt-Jakob disease, the fatal brain-wasting human equivalent of mad cow disease. This is the first known case in Hong Kong, adding to the list of approximately 100 confirmed cases worldwide. British neurologist Richard Kay believes the woman probably contracted the disease from eating beef in Britain, where she was a frequent visitor.
Crohn's Disease Linked to Dairy Bacterium
Many scientists believe Crohn's disease is caused by the same bacterium that causes Johne's (YO-nees) disease, an infection found in at least one in five U.S. dairy herds. Now U.S. dairy farmers are asking Congress for $1.3 billion to identify and kill infected cows.
Crohn's disease affects more than 500,000 people in the United States, causing such severe intestinal inflammation that hospitalization and even surgery are sometimes required.
Foot-and-Mouth Disease Causes Human Illness
In a review of 17 scientific studies on foot-and-mouth disease, Michael Greger, M.D., has determined that the illness can spread from animals to humans and that 400 cases across several continents have been reported.
Those at highest risk for the disease are butchers, livestock auctioneers, farm workers, veterinarians, lab workers, and children. The most frequent route of infection, however, is through ingestion of cheese and other dairy products. Symptoms include fever, headache, thirst, tonsillitis, and sometimes painful blisters on the hands, feet, and mouth. Laboratory research has shown that person-to-person infection can occur through coughing, sneezing, and breathing.
ALTERNATIVES TO ANIMAL EXPERIMENTATION
Rat Tests Under Fire
Although animal experiments often fail to accurately predict hazardous biological effects in humans, U.S. government agencies rely on these tests to evaluate a chemical's potential to cause cancer. The reliability of cancer tests using rats was once again called into question by a recent report showing that when the experiments were repeated, the results were the same only 57 percent of the time.
Gottman E, Kramer S, Pfahringer B, Helma C. Data quality in predictive toxicology: reproducibility of rodent carcinogenicity experiments. Environ Health Perspect. 2001;109:509-514.
Who Protects Animals in University Labs?
It is the job of animal care committees to scrutinize university animal experiments, but a new study shows their judgments to be as random as a coin toss.
As reported in Science, Scott Plous of Wesleyan University and Harold Herzog of Western Carolina University presented 150 research proposals to 50 randomly selected animal care committees from various U.S. colleges and universities, with each proposal evaluated by two separate committees. In most cases, proposals that were disapproved by one committee were approved by a second, even for experiments on dogs, cats, and primates that involved painful surgeries and death.
The approval process for animal experiments has remained largely unchanged since the mid-1980s.
Plous S, Herzog H. Reliability of protocol reviews for animal research. Science. 2001;293:608-609.
A Single Fatty Meal Can Harm Your Heart
Australian researchers fed volunteers a ham and cheese sandwich, a glass of whole milk, and a dish of ice cream. Just hours later, their cholesterol levels were elevated, and they experienced a 25-percent reduction in elasticity of their arteries—both important risk factors of heart attack.
The fat content of the experimental meal was 50 grams, still well below that of a typical fast-food meal such as a chicken sandwich and fries.
Nestel PJ, Shige H, Pomeroy S, Cehun M, Chin-Dusting J. Post-prandial remnant lipids impair arterial compliance. J Am Coll Cardiol. 2001;37:1929-1935.
AHA Issues New Warnings on Hormone Therapy
The American Heart Association (AHA) says there is not enough evidence to support the widely reported notion that hormone replacement therapy (HRT) protects the heart. In its new clinical recommendations, the AHA advises postmenopausal women with cardiovascular disease not to take hormones to try to improve heart health. Instead, they should quit smoking, get regular physical activity, and lose excess weight.
Risks of HRT include blood clots, endometrial cancer, breast cancer, and gallbladder disease.
Mosca L, Collins P, Herrington DM, et al. Hormone replacement therapy and cardiovascular disease: a statement for healthcare professionals from the American Heart Association. Circulation. 2001;104:499-503.
Clean Living Adds Years to Life Span
A new study finds that Seventh-day Adventists, many of whom follow a vegetarian diet, exercise regularly, and don't smoke, live significantly longer than their non-Adventist counterparts.
Researchers at Loma Linda University compared California Adventists to other Californians, all 30 and older, finding males gained more than seven years of life and women nearly four and one-half years. Although a great deal of evidence suggests that healthy lifestyle habits discourage many illnesses, this is the best study to illustrate that clean living is linked to longevity.
Fraser GE, Shavlik DJ. Ten years of life: is it a matter of choice? Arch Intern Med. 2001;161:1645-1652.
Birth Defects Decline with Folic Acid Fortification
A new study has found a 19-percent reduction in neural tube birth defects since folic acid fortification of the U.S. food supply.
The U.S. Public Health Service recommended in 1992 that all reproductive-aged women consume 400 micrograms of folic acid. However, a 1998 survey found that only 29 percent of U.S. women were doing so. In response, the FDA mandated folic acid supplementation in enriched grain products, expecting to add 100 micrograms of the nutrient to the daily diet of the average person. The most common neural tube defects are spina bifida and anencephaly.
Honein MA, Paulozzi LJ, Mathews TJ, Erickson JD, Wong LC. Impact of folic acid fortification of the U.S. food supply on the occurrence of neural tube defects. JAMA. 2001;285:2981-2986.
Vegan Diet Meets Children's Nutritional Needs
Children raised on a healthy, vegan diet of vegetables, fruits, whole grains, legumes, nuts, and seeds gain significant protection against overweight and diabetes and have much higher intakes of fiber, important antioxidants, and minerals than omnivorous children.
The American Dietetic Association has given the vegan diet the green light for children, saying it can provide all the necessary nutrients for growing infants, toddlers, and adolescents. Meal planning guidelines for nutritionists assisting vegan parents can be found in the June 2001 issue of the Journal of the American Dietetic Association.
Messina V, Mangels AR. Considerations in planning vegan diets: children. J Am Diet Assoc. 2001;101:661-677.