1. Department of Oral Pathology, School of Dentistry, Institute of Oral Bioscience, Brain Korea 21, Chonbuk National University, Jeonju 561-756, Republic of Korea
2. Department of Biochemistry, College of Medicine, Soonchunhyang University, Cheonan 330-090, Republic of Korea
3. Department of Oral Periodontology, School of Dentistry, Institute of Oral Bioscience, Chonbuk National University, Jeonju 561-756, Republic of Korea
4. Neural Injury Research Laboratory, Department of Neurology, Asan Life Science Institute, College of Medicine, University of Ulsan, Seoul 138-736, Republic of Korea
5. Department of Dental Hygiene, Division of Health Sciences, Cheongju University, Cheongju, 360-764, Republic of Korea