[1] Boston Univ, Med Ctr, Dept Pediat, Boston, MA 02118 USA
[2] Boston Univ, Sch Med, Boston, MA 02118 USA
[3] Univ Massachusetts, Med Ctr, Dept Pediat, Program Mol Med, Worcester, MA USA
[4] Frontier Sci & Technol Res Fdn, Brookline, MA USA
[5] Frontier Sci & Technol Res Fdn, Amherst, NY USA
[6] Boehringer Ingelheim Pharmaceut Inc, Ridgefield, CT 06877 USA
[7] Pediat AIDS Clin Trials Grp Operat Ctr, Rockville, MD USA
[8] Mt Sinai Hosp, Mt Sinai Sch Med, Dept Obstet Gynecol, New York, NY 10029 USA
[9] San Francisco Gen Hosp, Dept Obstet Gynecol, San Francisco, CA 94110 USA
[10] Univ Calif San Diego, Dept Pediat, La Jolla, CA 92093 USA
[11] San Juan City Hosp, Dept Pediat, San Juan, PR USA
[12] Northwestern Univ, Sch Med, Chicago, IL USA
[13] Childrens Mem Hosp, Dept Pediat, Chicago, IL 60614 USA