1. Department of Medicine, Division of Endocrinology, University of Texas Health Science Center at San Antonio , San Antonio, TX 78229
2. Sam and Ann Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio , San Antonio, TX 78229 , USA
3. Geriatric Research, Education, and Clinical Center, South Texas Veterans Health Care System , San Antonio, TX 78229 , USA