1. Department of Neurology; University of Michigan; Ann Arbor MI
2. Department of Endocrinology and Metabolism; Peking University People's Hospital; Beijing China
3. Department of Endocrinology and Metabolism; Beijing Pinggu Hospital; Beijing China
4. School of Public Health; University of Michigan; Ann Arbor MI
5. Division of Metabolism, Endocrinology and Diabetes; Department of Internal Medicine; University of Michigan; Ann Arbor MI