[1] John Radcliffe Hosp, Weatherall Inst Mol Med, Dept Clin Neurol, Oxford OX3 9DS, England
[2] John Radcliffe Hosp, Weatherall Inst Mol Med, Neurosci Grp, Oxford OX3 9DS, England
[3] Univ Hosp Leichester, Dept Neurol, Leicester, Leics, England
[4] Univ Hosp Coventry, Dept Neurol, Coventry, W Midlands, England
[5] Warshire NHS Trust, Coventry, W Midlands, England
[6] Morriston Hosp, Dept Neurol, Swansea, W Glam, Wales
[7] Shinshu Univ, Sch Med, Dept Med 3, Matsumoto, Nagano 390, Japan