1. Neurology Research; Veterans Affairs Medical Center; Oregon Health Sciences University; Portland OR 97201 U.S.A.
2. Department of Neurology; Oregon Health Sciences University; Portland OR 97201 U.S.A.
3. Department of Cell Biology and Anatomy; Oregon Health Sciences University; Portland OR 97201 U.S.A.
4. Neurological Sciences Center; Good Samaritan Hospital and Medical Center; Portland OR 97210 U.S.A.