October 28, 2005

CELL BIOLOGY: Two Genomes Cause Double Trouble In Cell
Cell division can backfire if the duplicated chromosomes are not evenly split between the two new daughter cells. A single chromosome misdirection can trigger the cells to fuse back together into one cell with a double genome contained in two mismatched nuclei. New research shows this may occur more often than anyone thought and, when combined with other genetic abnormalities, may lead to cancer, according to a pair of papers in the Oct. 13 Nature from the labs of Randy King and David Pellman. The findings are believed to be the first direct evidence backing a century-old idea that cell division failure alone may set the stage for some cancers.

MICROBIOLOGY: Sublethal Force: New Antibiotic Aims to Tame Bacterial Toxins
Using an innovative screening approach, John Mekalanos and Deborah Hung have identified a new class of antibiotics active against the cholera bacterium. While traditional antibiotics kill bacteria outright by interfering with processes essential for their survival, the new agents block production of bacterial proteins that promote infection and cause cholera symptoms. “What we’ve done is made a custom, organism-specific antibiotic against Vibrio cholerae,” said Mekalanos. The approach, described in the Oct. 13 online edition of Science, can be readily applied to other important pathogens, most of which produce their own toxins or other virulence factors.

HMS STATE OF THE SCHOOL: Martin Describes Growing Local, Global Network
In his eighth annual State of the School speech, HMS dean Joseph Martin described the School’s growth and changes in the context of increasing globalization. Martin highlighted changes in HMS’s internet and intranet services that allow students, researchers, and professors to exchange information or collaborate no matter where they are located; new programs in systems and chemical biology that bring the strategies and expertise of outside disciplines to bear on medical problems; and HMS publications that are reprinted in languages including Arabic, Indonesian, Turkish, and Russian.

HSPH STATE OF THE SCHOOL: Bloom and Ware Discuss Public Health Challenges
HSPH dean Barry Bloom (at right) and dean for academic affairs James Ware gave an overview of the School's accomplishments, fiscal health, and future goals in the fourth annual HSPH State of the School address. Among hundreds of public health challenges, the School has chosen the following major, cross-cutting agendas that exert a tremendous impact on the world and that need further study: the unfinished efforts against infectious diseases; the coming epidemic of chronic diseases; the unnecessary epidemic of violence, injury, and environmental threats; health disparities; and health system development and reform.

NEUROLOGY: Barrier Found to Nerve Regeneration
Adult neurons of the central nervous system cannot regenerate after injury; they face an inhibitory environment and have lost their intrinsic capacity to grow. Researchers hope it will be possible to encourage growth if they can identify the restraints. A study in the Oct. 7 Science from the lab of Zhigang He uncovers a surprising new player on the side of inhibition—the well-known epidermal growth factor (EGF) receptor. The molecule appears to mediate the inhibitory signals of both myelin and proteoglycans from the glial scar—a convergence of pathways in a field that has become increasingly complex.