A Change of Heart (IMAGE) University of Pennsylvania School of Medicine Caption tCardiomyocyte (center), showing protein distribution (green and red colors) indicative of a young cardiomyocyte. Credit Tae Kyung Kim, PhD, Perelman School of Medicine, University of Pennsylvania Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.