1. Biopharmaceutical Research Laboratories of Dong-A Pharmaceutical Co., Ltd., Kyunggi-Do 446-905, Korea.
2. Interdisciplinary Program of Biochemical Engineering and Biotechnology, Seoul National University, Seoul 151-744, Korea.
3. Department of Molecular Genetics and Biochemistry, University of Pittsburgh School of Medicine, Pennsylvania PA15261, USA.
4. Faculty of Pharmacy, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea.
5. Department of Surgery, University of Pittsburgh School of Medicine, Pennsylvania PA15261, USA.