1 Nashville VA Medical Center and Section of Surgical Sciences and Department of Cell and Developmental Biology and Epithelial Biology Center and Vanderbilt University, Nashville, Tennessee. Electronic address: jim.goldenring@vanderbilt.edu.
2 Division of Gastroenterology, Departments of Medicine, Pathology & Immunology, Developmental Biology, Washington University School of Medicine, St. Louis, Missouri. Electronic address: jmills@wustl.edu.