1. Section on Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA.
2. Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA.
3. Department of Surgery, Hypertension and Vascular Research Center, Wake Forest School of Medicine BioTech Place, Winston-Salem, North Carolina, USA.
4. Department of Pathology, Perinatal/Autopsy Pathology, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA.