Medicine’s dream of growing new human hearts and other organs to repair or replace damaged ones received a significant boost Sunday when University of Minnesota researchers reported success in creating a beating rat heart in a laboratory. Experts not involved in the Minnesota work called it ‘a landmark achievement’ and ‘a stunning’ advance. But they and the Minnesota researchers cautioned that the dream, if it is ever realized, was still at least 10 years away. Dr. Doris A. Taylor, the head of the team that created the rat heart, said she followed a guiding principle of her laboratory: ‘give nature the tools, and get out of the way.’ ‘We just took nature’s own building blocks to build a new organ,’ Dr. Taylor said of her team’s report in the journal Nature Medicine. The researchers removed all the cells from a dead rat heart, leaving the valves and outer structure as scaffolding for new heart cells injected from newborn rats. Within two weeks, the cells formed a new beating heart that conducted electrical impulses and pumped a small amount of blood. With modifications, scientists should be able to grow a human heart by taking stem cells […]