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RESEARCH ETHICS By Kristie Sullivan, M.P.H., and Nancy Beck, Ph.D.
Europeans Develop Nonanimal Marine Toxin Tests
Several European universities are working together to develop nonanimal tests to detect toxins emitted by certain types of algae. Currently, these aquatic toxins are detected by using mice in a painful, sometimes deadly test. In addition to ethical objections, this test method has raised serious concerns about accuracy. The universities are developing cell- and biosensor-based assays that could replace the use of mice. They intend to validate the tests for use in coastal communities worldwide at the end of a two-year grant. For more information, visit Alarmtox.net.
Nonanimal Model Aids Neurology Research
A new model of the motor nerves will help researchers better understand nerve structure and function and more easily test treatments for diseases like diabetic neuropathy and multiple sclerosis. This is the first lab-grown nerve model to contain functioning nodes of Ranvier and myelin sheaths, parts of nerve cells implicated in some diseases of the nervous system.
Researcher James Hickman, Ph.D., and colleagues at the University of Central Florida grew the cells for this breakthrough model without using fetal calf serum, which is derived from prenatal calves whose mothers are slaughtered while pregnant. The scientists used serum-free media instead. Many scientists are seeking alternatives to fetal calf serum because of ethical and scientific concerns about its use.
The new model also offers an improvement over animal-based models of diabetic neuropathy and multiple sclerosis, because scientists can view nerve processes as they are happening. “Being able to study these fully developed structures means we can really start looking at these things in a way that just wasn’t possible before,” says Dr. Hickman.
Rumsey JW, Das M, Stancescu M, Bott M, Fernandez-Valle C, Hickman JJ. Node of Ranvier formation on motoneurons in vitro. Biomaterials. 2009;30:3567-3572.
U.K. Using More Animals in Experiments
The numbers of animals used in laboratories in the United Kingdom rose to 3.7 million in 2008, a 14 percent increase from 2007. The U.K. Home Office reports that the rise was mainly due to increased use of fish, mice, primates, and some birds. Genetically modified mice were used in 38 percent of the procedures. The numbers of rats, guinea pigs, rabbits, and beagles decreased. Eighty-seven percent of the animals were used for research, such as immunological studies, pharmaceutical research and development, and cancer experiments. The rest were used for toxicology testing of products and chemicals, which is a reduction from 1995 levels but a 16 percent increase from 2007 levels. Laboratories in the United States also seem to be using more genetically modified mice, but comparisons with the U.K. are difficult because no U.S. agency tracks the number of mice, rats, and birds used in experiments. These species are excluded from the protections of the Animal Welfare Act.
U.K. Home Office. Statistics of Scientific Procedures on Living Animals, Great Britain 2008. Available at: http://www.homeoffice.gov.uk/rds/pdfs09/spanimals08.pdf. Accessed August 2009.
NUTRITION By Susan Levin, M.S., R.D., and Kathryn Strong, M.S., R.D.
Vegan Diets Get Thumbs Up for Bone Health
A lifelong vegan diet has no adverse effects on bone mineral density compared with an omnivorous diet, according to a new study of Vietnamese women. Researchers compared 105 postmenopausal Buddhist nuns following a vegan diet with 105 omnivorous women. The researchers analyzed bone mass at the lumbar spine, femoral neck, and whole body, and collected a food questionnaire for each participant. The vegan women consumed less calcium and their total protein intake was significantly less, but the two groups had comparable bone density.
Ho-Pham LT, Nguyen PLT, Le TTT, et al. Veganism, bone mineral density, and body composition: a study in Buddhist nuns. Osteoporos Int. 2009. Available at: http://www.springerlink.com/content/480pu7m6q1817w61/. Accessed August 2009.
Healthful Diets May Lower Risk of Respiratory Disease
Although chronic obstructive pulmonary disease, or COPD, is strongly related to smoking, new evidence shows that a healthy diet can help protect against COPD and other respiratory problems. In a study published in the June issue of Respiratory Research, researchers in Japan compared the diets of 278 adults with COPD with those of 340 healthy adults. They found that the healthy people consumed more soy products, more fruits and vegetables, and less red meat.
Hirayama F, Lee AH, Binns CW, et al. Soy consumption and risk of COPD and respiratory symptoms: a case-control study in Japan. Respir Res. 2009;10:56.
Fish and Fish Oil Linked to Diabetes Risk
Fish and omega-3 oil consumption is linked to increased risk of type 2 diabetes, according to a recent Harvard study in the American Journal of Clinical Nutrition. Researchers followed 195,204 adults for 14 to 18 years and found that the more fish or omega-3 fatty acids participants consumed, the higher their risk of developing diabetes. The increase in risk was modest for occasional fish eaters, but rose to a 22 percent increased risk for women consuming five or more fish servings per week.
Kaushik M, Mozaffarian D, Spiegelman D, Manson JE, Willett WC, Hu FB. Long-chain omega-3 fatty acids, fish intake, and the risk of type 2 diabetes mellitus. Am J Clin Nutr. 2009;90:613-620.
Processed Meats Increase Risk of Diabetes and Alzheimer’s
Consumption of nitrites, an additive used in many processed meats, may increase the risk of type 2 diabetes and other chronic diseases. Researchers examined mortality from diabetes, Alzheimer’s, and other conditions, and its relation to exposure to nitrites through processed and preserved foods, finding a positive correlation. Nitrites convert to nitrosamines in the body and can cause DNA damage, cell death, and cancer. The American Institute for Cancer Research recommends avoiding processed meats because of their link to colorectal cancer.
De la Monte SM, Neusner A, Chu J, Lawton M. Epidemiological trends strongly suggest exposures as etiologic agents in the pathogenesis of sporadic Alzheimer’s disease, diabetes mellitus, and non-alcoholic steatohepatitis. J Alzheimer’s Dis. 2009;17:519-529.