1 Department of Physiology and Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
2 High-Throughput Screening Core, University of Pennsylvania, Philadelphia, PA, USA.
3 Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, USA.
4 Department of Physiology and Pennsylvania Muscle Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA. [email protected].