[1] Massachusetts Gen Hosp, Shriners Burns Inst, Boston, MA 02114 USA
[2] Harvard Univ, Sch Med, Dept Surg, Boston, MA 02114 USA
[3] Inst Armand Frappier, Inst Natl Rech Sci, Laval, PQ H7V 1B7, Canada
[4] Stanford Univ, Sch Med, Dept Biochem, Stanford, CA 94305 USA