1. Laboratory for Radiopharmacy, Faculty of Pharmaceutical Sciences, K.U. Leuven, Leuven, Belgium, Department of Nuclear Medicine, K.U. Leuven, Leuven, Belgium, Rega Institute for Medical Research, K.U. Leuven, Leuven, Belgium, and Division of Molecular Medicine, K.U. Leuven, Leuven, Belgium