When recovering from a heart attack or stroke, the body must restore blood flow in order to resupply cells with oxygen. Ironically, the process of reoxygenation - so necessary for full recovery - also generates reactive oxygen species (ROS), molecules that induce apoptosis, or cellular death. Now, researchers at the University of Pennsylvania School of Medicine and the University of Iowa have identified a biochemical strategy to block ROS - which effectively prevents cellular damage and death. Their study is published in February’s Proceedings of the Natural Academy of Sciences.