1Department of Microbiology and Immunology, Diabetes and Medical Genetics, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, 29425
2Division of Endocrinology, Diabetes, and Medical Genetics, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, 29425
3Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, 20208
4Ralph H. Johnson VA Medical Center, Diabetes and Medical Genetics, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, 29425