 The trial is approved by the Institutional Review Boards for Human Studies of the Medical Faculties of the Johann Wolfgang Goethe-University FrankfurtMain 15906 and the University of Heidelberg ABmu-1792006 as well as the German Federal Drug Authority Bundesamt für Arzneimittel und Medizinprodukte. All participating individuals are informed on risks, benefit and the procedures of the study. All give written informed consent. The study is registered under the EudraCT-Nr. 2006-001367-36 and under the number NCT01030666. 