2006 DEC 4 - (NewsRx.com) -- Johns Hopkins scientists have successfully grown large numbers of stem cells taken from adult pigs' healthy heart tissue and used the cells to repair some of the tissue damage done to those organs by lab-induced heart attacks. Pigs' hearts closely resemble those in humans, making them a useful model in such research. Following up on previous studies, Hopkins cardiologists used a thin tube to extract samples of heart tissue no bigger than a grain of rice within hours of the animals' heart attacks, then grew large numbers of cardiac stem cells in the lab...