1. Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
2. Department of Neurosurgery, Nakamura Memorial Hospital, Sapporo, Japan
3. Department of Neurosurgery, Hokkaido Neurosurgical Memorial Hospital, Sapporo, Japan
4. Department of Cancer Pathology, Faculty of Medicine, Hokkaido University, Sapporo, Japan
5. Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo, Japan