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RESEARCH ETHICS By Kristie Stoick, M.P.H., and John J. Pippin, M.D., F.A.C.C.
Scientists at the University of New South Wales, Australia, have developed a way to test airborne toxicants for effects on human cells. Until now, the effects of airborne contaminants on the lungs have been assessed by forcing rats or other animals to inhale specific concentrations of chemicals for certain periods of time.
Dr. Amanda Hayes, along with her university colleagues Shahnaz Bakand and Chris Winder, has developed a way to expose cultured human lung cells on a porous polyester membrane to airborne pollutants or chemicals. The method’s performance compared favorably to animal-based tests.
In recognition of their work, Dr. Hayes and her colleagues were awarded the 2006 Australian Museum Voiceless Eureka Prize for Research, which rewards scientists for work that reduces the use of animals in science.
Research has demonstrated that this method, which measures a contaminant’s effects on cell growth and other biological endpoints, can predict the effects of industrial chemicals like formaldehyde, as well as pollutants such as cyanide and ammonia. Researchers believe that the method will be especially useful in evaluating new technologies like nanoparticles—miniscule particles of commonly used materials such as carbon or silver.
Most importantly, this method will allow assessment of the effects of pollutants directly on human lung cells, instead of animal cells. “In vitro toxicity tests can improve the scientific, economic, and ethical value of research and play a significant role in the screening of toxic chemicals and the replacement of animals,” Dr. Hayes said.
University of New South Wales Web site. Available at: http://www.unsw.edu.au/news/pad/articles/2007/feb/soft_cell.html. Accessed February 16, 2007.
Bookmark Your Browsers: Alternatives in Toxicology Database Launched
Scientists looking for alternatives to using animals in their research now have a new online tool: DB-ALM. The European Centre for the Validation of Alternative Methods has launched an online database containing the latest non-animal toxicology testing methods. Methods are categorized into in vitro and in silico (computer-based) selections. The database also includes an extensive bibliographic section with thousands of supporting research papers, validation reports, and specific protocols for use of the methods.
European Centre for the Validation of Alternative Methods Web site. Available at: http://ecvam-dbalm.jrc.cec.eu.int. Accessed February 16, 2007.
Human Cellular Metabolism—Computerized
By collecting and analyzing decades worth of research on metabolic pathways and combining this data with the decoding of the human genome, Dr. Natalie Duarte and colleagues have used a supercomputer to do what no scientist working with genetically modified animals has ever been able to do: create a model of detailed metabolic processes at work in human cells. This very promising new technology, developed at the University of California at San Diego, could allow researchers to study and potentially alter the metabolic underpinnings of some diseases. It also could be used to model metabolic reactions to chemicals using human cells, which would help improve in vitro toxicity test methods.
Duarte N, Becker S, Jamshidi N, et al. Global reconstruction of the human metabolic network based on genomic and bibliomic data. PNAS. 2007;104:1777-1782.
NUTRITION By Dulcie Ward, R.D., and Susan Levin, M.S., R.D.
Plant Sources of Omega-3 Fatty Acids Beneficial to Bone Health
A study at Pennsylvania State University showed that omega-3 fatty acids from plant sources (for example, walnuts and flaxseed) promote bone formation and inhibit bone loss. A randomized crossover study looked at 23 adult participants on three different diets with varying ratios of omega-6 to omega-3 acids. The group with the lowest omega-6-to-omega-3 ratio had significantly lower levels of a biomarker for bone loss compared with the other two groups. Experts often emphasize the ratio (with a smaller ratio being ideal) of omega-6 to omega-3 and not the total consumption of omega-3. Consumption of walnuts and flaxseed has also shown a beneficial effect on risk of cardiovascular disease.
Griel AE, Kris-Etherton PM, Hilpert KF, et al. An increase in dietary n-3 fatty acids decreases a marker of bone resorption in humans. Nutr J. 2007;6:2.
Red Meat Linked to Heart Disease in Women with Diabetes
A new study finds increased iron intake and red meat consumption add additional risk for heart disease among women with type 2 diabetes. Researchers from the Harvard School of Public Health studied 6,161 women with type 2 diabetes from the Nurses’ Health Study. Women with the highest intake of heme iron (iron found mainly in red meats, poultry, and fish) had a 50 percent greater risk of coronary heart disease than those with the lowest intake. Red meat in particular was associated with an increased risk. Adults with diabetes are already at least twice as likely as others to have heart disease or a stroke.
Qi L, VanDam RM, Rexrode K, Hu FB. Heme iron from diet as a risk factor for coronary heart disease in women with type 2 diabetes. Diabetes Care. 2007;30:101-106.
Medical Students and Vegetarian diets
A new study shows that many medical students now follow vegetarian diets and that these students had better health and improved nutrition compared with their non-vegetarian classmates. Emory University researchers examined the prevalence of vegetarian diet patterns among nearly 900 medical students and found that 7.2 percent of students identified themselves as vegetarians. This number declined slightly throughout the years of
medical school, paralleling an unfortunate overall decline in positive health-related habits among doctors in training.
Spencer EH, Elon lk, Frank E. personal and professional correlates of uS medical students’ vegetarianism. J Am Diet Assoc. 2007;107:72-78.