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Table of Contents NRC Denies Poisened Postdoc's Request No Human Clones A Funny Spin to Science Anti-Obesity Drug Withdrawn Haverford Finds Friend in Science More Than Padded Cells Cancer Checkpoint Super Grant STILL A MYSTERY: The identity of the person who poisoned Maryann Wenli Ma and Bill Wenling Zheng, shown here with their son, remains unknown. On September 17, the Nuclear Regulatory Commission (NRC) turned down a petition by Maryann Wenli Ma, the visiting Chinese postdoc at the National Institutes of Health who was poisoned in 1995 with 32P while 17 weeks' pregnant, and her husband, Bill Wenling Zheng, also an NIH postdoc, to suspend or revoke NIH's nuclear materials license. NRC, however, did cite NIH for two violations: exceeding the annual occupational radiation dose limit for an employee (for Ma), and exceeding the NRC dose limit for a member of the public (for one of the 25 NIH employees contaminated by water from a water cooler in the same incident). Because NIH was cooperative during the investigation and, according to NRC documents, did not contribute "directly or indirectly to the deliberate misuse of licensed material," and "could not reasonably have foreseen that an employee would maliciously misuse licensed material," no further enforcement action will be taken against it in this case. Earlier this summer, NRC let stand a civil penalty of $2,500 on NIH, which NIH had appealed. The mysterious poisoning occurred when Ma and Zheng worked in the National Cancer Institute's (NCI's) Laboratory of Molecular Pharmacology (M.E. Watanabe, The Scientist, Feb. 5, 1996, page 1). NRC officially closed its books on this case with this decision, which still leaves the perpetrator and source of the 32P unknown. An investigative report released by NRC clears NCI senior research investigator John Weinstein, who brought the couple to the United States, of Ma and Zheng's charges that he tried to pressure Ma to have an abortion, interceded in her treatment for radiation poisoning, and prevented her from declaring her pregnancy to NIH prior to the incident. The report, says Weinstein, "succinctly puts the entire matter in proper perspective, exonerating me completely point by point." David Marshall of the Washington, D.C., law firm of Bernabei and Katz, an attorney for Ma and Zheng, states that the NRC report is "a whitewash, and it's part of the continuing cover-up of government responsibility for Dr. Ma's contamination." CLONE-FREE: Ralph Yount announced FASEB's voluntary moratorium on human cloning, arising from the recent news of a cloned sheep. In the wake of news about Dolly, the cloned sheep, the Federation of American Societies for Experimental Biology (FASEB) has adopted a voluntary moratorium on cloning humans. FASEB, a coalition of 14 life sciences societies with total membership exceeding 52,000 biomedical and biological scientists, represents most people in America with the capability to clone humans. A number of bills opposed to human cloning are in various stages of development at both the federal and state levels. "We believe a voluntary moratorium can be more effective than legislation," said the federation's president, Ralph G. Yount, a professor of chemistry in the department of biochemistry and biophysics at Washington State University, in a press briefing on September 18. He added that the moratorium is not a response to specific proposed laws but is meant as a policy statement that could be helpful to legislators. Unanimously approved by FASEB's public affairs executive committee, the resolution defines human cloning as "the duplication of an existing or previously existing human being by transferring the nucleus of a differentiated, somatic cell into an enucleated human oocyte and implanting the resulting product for intrauterine gestation and subsequent birth." Yount indicated this does not preclude experimentation on repair and regeneration of human tissues for treating various diseases. He said he has not heard of any opposition to the moratorium. In accord with recommendations from the National Bioethics Advisory Commission, the moratorium will be reviewed after five years for possible renewal. FUNNY TOME: In September, Weekly Reader launched Science Spin, a lighthearted look at science in the news. After 50 years of serious reporting, the world's largest newspaper for children can no longer keep a straight face. In September, Weekly Reader, based in Stamford, Conn., launched Science Spin. The monthly publication's lighthearted reports on science in the news are targeted to children from kindergarten through sixth grade. For example, instead of dryly listing facts about how the senses work, the editors of Science Spin enlist the help of a frog that tastes food by vomiting. Forrest Stone, executive editor at Weekly Reader, explains, "We thought that this was an opportunity to use humor to teach because kids really respond well to it. So we tried to be impeccably accurate with science, but inject it with fun. We hope that this approach will help to sustain their interest and desire in science during tough times of development." Weekly Reader began to circulate preview issues of Science Spin in April after marketing studies showed elementary teachers requesting more literature support in science. By September, circulation for the first edition was already at 600,000. The main publication, Weekly Reader, has a circulation of more than 7 million and is used by one in four teachers in the United States. Current Science and Current Health, which target secondary-school students, complete Weekly Reader's stable of science publications. On September 15, the Food and Drug Administration (FDA) announced that the maker of anti-obesity drugs dexfenfluramine and fenfluramine had agreed to withdraw the products from the market. Wyeth-Ayerst Laboratories of Philadelphia manufactures and markets dexfenfluramine as Redux for Interneuron Pharmaceuticals Inc. Lexington, Mass. American Home Products Corp., the Madison, N.J.-based parent company of Wyeth-Ayerst, also makes and markets fenfluramine as Pondimin. FDA moved to withdraw the products after physicians studied users of the fen-phen and dexfen-phen drug combinations who had no signs of heart disease. Echocardiograms revealed about 30 percent of 291 asymtomatic patients had abnormal heart valves. Animal models also demonstrated that each of the drugs could cause brain damage in animal models (U.D. McCann et al., JAMA-Journal of the American Medical Association, 278:666-72, 1997). FDA is not moving to withdraw phentermine from the market, as studies attribute heart valve damage risk to only fenfluramine and dexfenfluramine. Phentermine is made and marketed as Ionamin by Medeva Pharmacueticals Inc., based in Rochester, N.Y. Just a month earlier, FDA made headlines when it proposed a ban on the over-the-counter laxative ingredient phenolphthalein. Studies show that rats given 100 times the human dose of the drug develop tumors. Other studies show that 30 times the human dose administered for six months caused tumors and genetic damage in mice. RESEARCHER TAKES HELM: Thomas Tritton, a cancer researcher by trade, became the 12th president of Haverford College. A cancer researcher has been named president of Haverford College in suburban Philadelphia. Thomas R. Tritton, former provost at the University of Vermont, had spent 25 years in cancer research prior to his appointment at Haverford, a Society of Friends (Quaker) institution. Tritton, 48, was inaugurated as the 12th president of the 164-year-old college on September 27. From the perspective of a scientist, Tritton believes that the future of Haverford is bright. "One of our focuses will be building a new facility to house the sciences under one roof," he says. "The sciences are facilities-intensive and have certain infrastructure needs. By bringing all the sciences into a single facility, we hope to enable people to rub shoulders and exchange ideas. This kind of exchange produces the most exciting and innovative science. We want our infrastructure to reflect this newness and exchange." Tritton's career in academic science began as a chemistry student at Ohio Wesleyan College, where he converted to Quakerism despite the college's Methodist affiliation. After receiving a Ph.D. in biochemistry from Boston University, Tritton spent two years as a postdoctoral fellow at Yale University. In 1985, he began a seven-year tenure as deputy director of the Vermont Comprehensive Cancer Center while also serving as a professor in pharmacology at the University of Vermont. By isolating nerve cells from glia, the brain cells that wrap around them, Stanford University researchers have shown that glia play an active role in brain function. Glia have in the past been considered passive-the insulation to the nerve cell's wire. When Barbara A. Barres, an associate professor of neurobiology, and postdoctoral fellow Frank W. Pfrieger, now a group leader at the Max Delbück Center for Molecular Biology in Berlin, cultured rat retinal ganglion cells separately from their glia, the ganglion cells formed synapses and passed on some electrical messages (F.W. Pfrieger, B.A. Barres, Science, 277:1684-7, 1997). But the frequency of postsynaptic currents increased by 70-fold in ganglion cells with glia cells. Glia cultured alone produced an as-yet-unidentified protein or chemical factor that may facilitate the electrochemical communication. Adding that factor to the ganglion increased synaptic activity almost as much as adding the glia cells. "The next step is to purify and identify the molecule that the glia cells are releasing," Barres says. Other questions remain as well. The ganglion cells in the study use glutamate to send positive signals. Less prevalent cells in the brain use other chemicals to send negative signals. While the study demonstrates the importance of glia in isolated cell cultures, future research should probe how glia work in the intact brain, where they make up about 90 percent of the cells. CELLULAR SIGNALS: Helen Piwnica-Worms and a team of Washington University researchers identified potential ways to make cancer cells divide before their genetic material has been replicated. Short-circuiting cell cycle checkpoints-molecular traffic signals that control the order and timing of cell cycle transitions-could combat cancer by telling the rogue cells to divide prematurely, a team of Washington University researchers has found (C.-Y. Peng et al., Science, 277:1501-5, 1997). The researchers examined Cdc25C, a protein that gives the green light for a cell to divide after DNA and RNA replication. They found that the protein loses a phosphate group at a potentially important site prior to mitosis. In a mutant version of the protein without the phosphate, the cells began to divide before their genetic material was replicated. Without the whole Cdc25C, "the cells can't detect a problem, and they keep going," says Helen Piwnica-Worms, an associate professor of cell biology and physiology at Washington University in St. Louis and an associate investigator with the Howard Hughes Medical Institute. The researchers also identified a yeast protein called Chk1 that halts cellular division when it detects damage. Piwnica-Worms and collaborators at the Baylor College of Medicine in Houston identified a gene that performs the same function in humans (Y. Sanchez et al., Science, 277:1497-1501, 1997). Cancer drug researchers could key on both Cdc25C and Chk1 to develop new cancer treatments, Piwnica-Worms says. "This work establishes targets for drug discovery." REEVE MEDALIST: The Salk Institute's Fred Gage received the $50,000 Christopher Reeve Research Medal for his work in cellular regeneration. Christopher Reeve, the actor once most known for his portrayal of Superman and now the person most responsible for raising awareness of spinal cord injury research, presented Fred. H. Gage, a genetics professor at the Salk Institute for Biological Studies in La Jolla, Calif., an award for $50,000 last month. The Christopher Reeve Research Medal was funded by philanthropist Joan Irvine Smith, who is helping establish the Reeve-Irvine Research Center at the University of California, Irvine. Gage's work involves making genetically engineered cells that can induce cellular regeneration. "We developed methods for engineering cells to make and express neurotrophic cells," he explains. Gage credits Reeve for supporting basic science research during a time when government budgets may be tilting toward applied science. The actor has also made more research possible through his high-profile campaign for more funds and more research devoted to spinal cord injuries. "He's helped the private sector get involved in this and increased the amount of giving by research foundations," Gage says.

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