1. University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555, USA
2. Northwestern University, Feinberg School of Medicine, 201 East Huron Street, Chicago, IL 60611, USA
3. Otsuka Maryland Research Institute, Inc., 2440 Research Boulevard, Rockville, MD 20850, USA
4. University of Texas Medical Branch, Division of Cardiology, 5106 John Sealy Annex, 301 University Boulevard, Galveston, TX 77555-0553, USA.