September 1998

A proposed plan to screen about 15,000 commercial chemicals that may interact harmfully with the endocrine system could be one of the most ambitious and expensive such efforts ever. The first tier of the two-part plan would cost an estimated $200,000 per chemical for high throughput screening. Those screens would test chemicals for interactions with five endocrine receptors, including estrogen, androgen, and thyroid receptors. Chemicals testing positive would move on to the next level, which co

Also See: Breadth of Biodiversity After months of complaints, hundreds of scientists will finally be able to use a long-coveted recombinant technology without looking over their shoulders. On August 19, National Institutes of Health Director Harold Varmus announced an agreement with DuPont Pharmaceuticals that will enable NIH and NIH-supported researchers to use a DuPont-developed technology, called Cre-lox, without compromising the company's ability to receive the appropriate value for commer

For a thing that is "nothing," placebo has been much in the news lately. Whenever the media have mentioned placebo this year, it often has been in the context of clinical trials overseas for treatments to prevent perinatal HIV transmission. The studies were controversial because most of them employed placebo controls with the various treatments being tested, although trials in the United States and France already had indicated that the antiretroviral drug zidovudine (AZT) reduced the incidence

Antifreeze proteins produced in some fish have hooked the attention of industry. But chemists are still casting inquiries into how these proteins act to prevent some species of flounder, cod, and sculpin from icing up in below-zero Centigrade water. RED HERRING: Although antifreeze proteins produced by the flounder are the most studied, they may be the least representative. Scientists at the 216th American Chemical Society Meeting in Boston last month trolled through the merits of a number of

BIODIVERSITY ABOUNDS: Algae and sponges line the underwater ledges of Navassa, a tiny, uninhabited island in the Caribbean that recently got a rare visit from scientists. A recent expedition has revealed an unexpected breadth of biological diversity on a rare untouched patch of wilderness. Led by Center for Marine Conservation (CMC) scientists Michael Smith and Nina Young, 14 researchers set out to survey a tiny U.S.-owned island 40 miles west of Haiti in the Greater Antilles. Part of the Unite

A fat substitute made its public debut in an oatmeal raisin cookie last month. The substitute, a coarse beige-yellow flourlike substance called Nu-Trim, contains high percentages of ß glucans--the soluble fibers that lower cholesterol through the same mechanisms as oat bran. While those mechanisms are not well understood, they are effective, remarked the product's developer, George E. Inglett , of the U.S. Department of Agriculture (USDA) Agricultural Research Service in Peoria, Ill. Ear

J.E. Brenman, D.S. Chao, S.H. Gee, A.W. McGee, S.E. Craven, D.R. Santillano, Z.Q. Wu, F. Huang, H.H. Xia, M.F. Peters, S.C. Froehner, D.S. Bredt, "Interaction of nitric oxide synthase with the postsynaptic density protein PSD-95 and alpha 1-syntrophin mediated by PDZ domains," Cell, 84:757-67, 1996. (Cited in more than 215 papers since publication) Comments by David S. Bredt, assistant professor of physiology at the University of California at San Francisco School of Medicine Nitric oxide (

C.E. Yu, J. Oshima, Y.H. Fu, E.M. Wijsman, F. Hisama, R. Alisch, S. Matthews, J. Nakura, T. Miki, S. Ouais, G.M. Martin, J. Mulligan, G.D. Schellenberg, "Positional cloning of the Werner's syndrome gene," Science, 272:258-62, 1996. (Cited in more than 175 papers since publication) Comments by Gerard D. Schellenberg, associate director for research, Geriatric Research Education and Clinical Center, Veterans Affairs Medical Center, Seattle Aging is a real stumper. Is it the result of natural we

What do I do with aqueous low-level radioactive waste? As a radiation safety officer for a small biotechnology company, I found solving that problem to be the most difficult and time-consuming aspect of my job. Faced with limited access to disposal sites, budget-busting costs, and a small waste storage room, I've had to rely completely on decay-in-storage to cope with low-level radioactive waste. Typically, we hold radioactive waste with half-lives less than 90 days for a period equal to 10 ha

Particles from PerSeptive Biosystems PerSeptive Biosystems' BioMag® product line includes streptavidin-coupled superparamagnetic particles that can be used to capture biotinylated compounds. The company has recently developed a more efficient method for coupling streptavidin to the BioMag® particles. The resultant BioMag® Streptavidin Ultra-Load Particle has more attached streptavidin, and therefore a greater biotin-binding capacity, than did previous versions of the product. The im

Date: September 14, 1998 Catalog Peptide Providers Table In the last 20 years or so, numerous peptides with a diverse array of biological activities have been identified. In the same time period, the advent of automated peptide synthesis has made these reagents cheap and easy to produce in large quantities. These developments have created a new class of research reagents, known as biologically active peptides. Many biologically active peptides occur naturally; however, many others have been de

Date: September 14, 1998Tables 1-4 While at one time RNA isolation was a painstaking endeavor, requiring careful sterilization of reagents, treatment of equipment, and lengthy centrifugation--often stretching over several days--kits for total RNA purification now provide rapid protocols with RNase-free reagents that can cut prep time down to under an hour. As important as saving time, these quick, often single-step protocols also reduce the possibility of degradation, always a concern with RNA