[1] Univ Glasgow, Dept Clin Oncol, Beatson Oncol Ctr, Glasgow G11 6NT, Lanark, Scotland
[2] Univ Glasgow, So Gen Hosp, Dept Neurosurg, Glasgow G51 4TF, Lanark, Scotland
[3] Univ Glasgow, Inst Virol, Div Virol, Glasgow G11 5JR, Lanark, Scotland
[4] So Gen Hosp, Inst Neurol Sci, Neurovirol Res Labs, Glasgow G51 4TF, Lanark, Scotland