1. Department of Physiology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104.
2. Section of Cardiology, Department of Clinical Studies, Veterinary Hospital of the University of Pennsylvania, Philadelphia, PA 19104.
3. Department of Physical Therapy, University of Florida, Gainesville, FL 32610.
4. Departments of Pathology and Laboratory Medicine, Neurology, and the Gene Therapy Center, University of North Carolina–Chapel Hill, Chapel Hill, NC 27514.
5. Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL 32610.