1. Division of Endocrinology, Diabetes and Metabolism Department of Medicine University of Illinois at Chicago Chicago IL USA
2. Mass Spectrometry Core Research Resource Center Office of Vice Chancellor for ResearchUniversity of Illinois at Chicago Chicago IL USA
3. Division of Pulmonary and Critical Care Medicine Department of Medicine Faculty of Medicine Chulalongkorn University Bangkok Thailand
4. Excellence Center for Sleep Disorders King Chulalongkorn Memorial Hospital Thai Red Cross Society Bangkok Thailand
5. Division of Endocrinology and Metabolism Department of Medicine Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok Thailand
6. Jesse Brown Veterans Affairs Medical Center Chicago IL USA
7. Research Informatics Core Research Resources Center University of Illinois at Chicago Chicago IL USA