[1] Univ Sao Paulo, Clin Hosp Ribeirao Preto, Ribeirao Preto, Brazil
[2] Univ Sao Paulo, Ribeirao Preto, Brazil
[3] Univ Sao Paulo, Clin Hosp Ribeirao Preto, Ribeirao Preto, Brazil
[4] UCL Queen Sq Inst Neurol, Dept Neuromuscular Dis, London, England
[5] Sao Paulo State Univ, Sch Med Ribeirao Preto, Ribeirao Preto, Brazil