1. University of Edinburgh; Centre for Clinical Brain Sciences; The Chancellor's Building 49 Little France Crescent Edinburgh UK EH16 4SB
2. Danderyd Hospital; Department of Clinical Sciences, Karolinska Institutet; Stockholm Sweden SE-182 88
3. Oslo University Hospital; Department of Internal Medicine; Oslo Norway NO-0407
4. University of Washington; Department of Medicine (Division of Hematology), Department of Neurology; 325 Ninth Avenue Box 359756 Seattle Washington USA 98104