[1] Univ Basel Hosp, CH-4031 Basel, Switzerland
[2] Univ Rochester, Rochester, NY 14627 USA
[3] Mt Sinai Sch Med, New York, NY USA
[4] St Michaels Hosp, Toronto, ON M5B 1W8, Canada
[5] Vrije Univ Amsterdam Med Ctr, Amsterdam, Netherlands
[6] Biogen Idec Inc, Cambridge, MA USA