1. Clinical Research Services Core, Translational Research Institute, University of Arkansas for Medical Sciences (UAMS), Little Rock, AR, USA
2. Department of Biostatistics, College of Medicine, University of Arkansas for Medical Sciences (UAMS), Little Rock, AR, USA
3. Department of Obstetrics and Gynecology, College of Medicine, University of Arkansas for Medical Sciences (UAMS), Little Rock, AR, USA
4. Department of Pathology, College of Medicine, University of Arkansas for Medical Sciences (UAMS), Little Rock, AR, USA