1. Department of Internal Medicine, Institute of Endocrine Research, Yonsei University College of Medicine, Seoul, Korea.
2. Brain Korea 21 Plus Project for Medical Science, Yonsei University, Seoul, Korea.
3. Department of Internal Medicine, Chaum Life Center, CHA University College of Medicine, Seoul, Korea.
4. Department of Ophthalmology, Institute of Vision Research, Yonsei University College of Medicine, Seoul, Korea.