1. Department of Neurology, University of Michigan, Ann Arbor, Michigan;
2. Department of Internal Medicine, Division of Metabolism, Endocrinology, and Diabetes, University of Michigan, Ann Arbor, Michigan;
3. Sigma-Tau Research, Sigma-Tau Pharmaceuticals, Gaithersburg, Maryland;
4. Departments of Pathology and Neurology, Wayne State University, Detroit, Michigan.