1. Department of Medicine, Penn State College of Medicine , Hershey, PA , USA
2. Université de Poitiers , Poitiers , France
3. Department of Surgery, Division of Colon and Rectal Surgery, Penn State Milton S. Hershey Medical Center , Hershey, PA , USA
4. Department of Medicine, Feinberg School of Medicine, Northwestern University , Chicago, IL , USA
5. Department of Internal Medicine, University of Utah School of Medicine , Salt Lake City, UT , USA
6. Department of Biochemistry and Molecular Biology, Penn State College of Medicine , Hershey, PA , USA
7. Department of Internal Medicine, College of Medicine, University of Kentucky , Lexington, KY , USA