1. From the Division of Biopharmaceutics (R.O., M.H., R.B.H., I.M., Z.L., T.J.C.V.B., M.V.E.), Leiden/Amsterdam Center for Drug Research, Gorlaeus Laboratories, Leiden University, Leiden, The Netherlands; From the Center for Liver, Digestive and Metabolic Diseases (J.K., F.K.), Laboratory of Pediatrics, University Medical Center Groningen, Groningen, The Netherlands.