1. Departments of Neurology OLVG; OLVG West, Jan Tooropstraat 164, 1061 AE, Amsterdam and Zaans Medisch Centrum; Zaandam the Netherlands
2. Radboud University Nijmegen Medical Center; Nijmegen the Netherlands
3. Assistance Publique Hôpitaux de Paris, Service de Biochimie, Hôpital Pitié-Salpêtrière; Paris France