1. Division of Rheumatology, Department of Medicine, Beth Israel Hospital, the Charles A. Dana Research Institute, the Harvard-Thorndike Laboratory, Harvard Medical School, Boston, MA 02215.
2. Department of Medicine, Brigham and Women's Hospital, Harvard School of Public Health, Boston, MA 02115.
3. Center for Neurologic Diseases, Division of Neurology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115.