[1] Johns Hopkins Univ, Sch Med, Inst Cell Engn, Stem Cell Biol Program, Baltimore, MD 21218 USA
[2] Johns Hopkins Univ, Sch Med, Mckusick Nathans Inst Genet Med, Baltimore, MD USA
[3] Johns Hopkins Univ, Sch Med, Cellular Imaging Sect & Vasc Biol Program, Inst Cell Engn, Baltimore, MD USA
[4] Johns Hopkins Univ, Sch Med, Div MR Res, Russell H Morgan Dept Radiol & Radiol Sci, Baltimore, MD USA
[5] Johns Hopkins Univ, Whiting Sch Engn, Dept Chem & Biomol Engn, Baltimore, MD USA
[6] Johns Hopkins Univ, Sch Med, Dept Gynecol & Obstet, Baltimore, MD USA