[1] Med Univ Innsbruck, Dept Neurol, Innsbruck, Austria
[2] AOU Citta Salute & Sci Torino, Multiple Sclerosis Ctr & Neurol IU, Dept Neurosci & Mental Hlth, Turin, Italy
[3] Reg Hosp Horsens, Dept Clin Biochem, DK-8700 Horsens, Denmark
[4] Univ Med Ctr Ljubljana, Dept Neurol, Ljubljana, Slovenia
[5] Univ Perugia, Dept Med & Surg, Sect Neurol, Perugia, Italy
[6] Univ Appl Sci, FH Campus Wien, Vienna, Austria
[7] Amsterdam UMC, Dept Neurol & Neurophysiol, Amsterdam Neurosci, VUMC, Amsterdam, Netherlands
[8] UCLouvain, Clin Univ St Luc, Brussels, Belgium
[9] Univ Hosp Southern Denmark, Sygehus Sonderjylland, Dept Reg Hlth Res, Hadersleben, Denmark
[10] Klinikum Ottakring, Dept Neurol, Vienna, Austria
[11] Univ Gothenburg, Inst Neurosci & Physiol, Sahlgrenska Acad, Dept Clin Neurosci, Gothenburg, Sweden
[12] Univ Ljubljana, Fac Med, Ljubljana, Slovenia
[13] Vrije Univ, Dept Clin Chem, Neurochem Lab, Amsterdam Neurosci,Amsterdam UMC, Amsterdam, Netherlands
[14] Maggiore Carita Univ Hosp, Dept Translat Med, Neurol Unit, Novara, Italy