In Brief; November 1999; Scientific American Magazine; by Yam; 2 Page(s)
Neural Fountain of Youth Age-related changes to the brain may be physically reversible,say Mark Tuszynski of the University of California at San Diego and his colleagues.Using rhesus monkeys,they targeted cholinergic neurons,which regulate cortical and hippocampal areas-the main sites of cognitive functions.Grafted with neural tissue that had been genetically modified to produce nerve growth factor, the cholinergic neurons,which normally shrivel with age and lose function, nearly returned to normal size;92 percent of the old neurons began functioning again.The team,which reported the study in the Proceedings of the National Academy of Sciences,is now examining whether the grafts produced behavioral and functional changes.
Planet of the Grapes Sixteen venerable wine grapes,including chardonnay, aligote and gamay noir, had at one point in their ancestry a variety called gouais blanc-considered so poor that it is no longer planted in France and was a target of a medieval ban. A U.S.-French collaborative describes in the September 3 Science how it took leaf samples from 300 grape varieties and generated DNA profiles for each to determine that the 16 types originally descended from pinot,a noble red grape of Burgundy and Champagne, and gouais blanc. The genetic diversity of the two may explain the quality of the resulting offspring,and knowing the lineage should help grape breeders avoid bad hybrids.