[1] IRCCS Osped Pediat Bambino Gesu, Rome, Italy
[2] Hosp Sick Children, Toronto, ON M5G 1X8, Canada
[3] Roche Prod Ltd, Welwyn Garden City AL7 3AY, Herts, England
[4] Chugai Pharmaceut Co Ltd, Tokyo, Japan
[5] Yokohama City Univ, Sch Med, Yokohama, Kanagawa 232, Japan
[6] Kagoshima Univ, Fac Med, Sch Hlth Sci, Kagoshima 890, Japan
[7] Italy Univ Genoa, Genoa, Italy
[8] Ist Giannina Gaslini, I-16148 Genoa, Italy