1. a Brigham and Women's Hospital, MGH Institute of Health Professions , Boston , MA , USA
2. b University of North Carolina , Wilmington , NC , USA
3. c Universidad del Valle , Cali , Colombia
4. d Texas A & M University , Corpus Christi , TX , USA
5. e Hunter College, City University of New York , New York City , NY , USA
6. f University of California, San Francisco , San Francisco , CA , USA
7. g Ben Taub General Hospital , Houston , TX , USA
8. h Rutgers University , Newark , NJ , USA
9. i Greenwich House , New York City , NY , USA
10. j University of Pennsylvania , Philadelphia , PA , USA
11. k Ohio State University , Columbus , OH , USA
12. l University of Oslo , Oslo , Norway
13. m National Institutes of Health/National Institute of Neuromuscular Diseases Section , Bethesda , MD , USA
14. n Chang Gung University , Toa-Yuan , Taiwan
15. o University of Puerto Rico , San Juan , Puerto Rico
16. p Massachusetts General Hospital , Boston , MA , USA
17. q New England AIDS Education and Training Center , Boston , MA , USA