1. WCU Department of Molecular Medicine and Biopharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul 151-742, Republic of Korea
2. Department of Materials Science and Engineering, Yonsei University, Seoul 120-749, Republic of Korea
3. Department of Otolaryngology, Asan Medical Center, College of Medicine, University of Ulsan, Seoul 138-736, Republic of Korea
4. Department of Bioengineering, College of Engineering, and Institute for Bioengineering and Biopharmaceutical Research, Hanyang University, Seoul 133-791, Republic of Korea
5. Hanyang University Institute of Aging Society, Seoul 133-791, Republic of Korea
6. Research and Development Center, Mediplex Corp., Seoul 151-742, Republic of Korea