1. University of Pittsburgh; Pittsburgh PA USA
2. University at Buffalo; Buffalo NY USA
3. University of Michigan; Ann Arbor MI USA
4. University of California; Los Angeles Los Angeles, CA USA
5. Brigham and Women's Hospital; Boston MA USA
6. University of Massachusetts Medical School; Worcester MA USA
7. The University of Tennessee Health Science Center; Memphis TN USA
8. University of Florida College of Medicine; Gainesville FL USA
9. Vanderbilt University Medical Center; Nashville TN USA