1. Second Department of Neurology, Attikon Hospital, University of Athens, Athens, Greece.
2. First Department of Neurology, Aeginition Hospital, University of Athens, Athens, Greece.
3. Second Department of Medicine, Renal Unit, Attikon Hospital, University of Athens, Athens, Greece.
4. Department of Neurology, Democritus University of Thrace, University Hospital of Alexandroupolis, Alexandroupolis, Greece.