1. Institute of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, Leipzig Universität, 04103 Leipzig, Germany, Department of Neurology, Kuopio University, Kuopio, Finland, and Section of Neuropathology, Kuopio University, Kuopio, Finland, Department of Genetics and Pathology, Uppsala University, S-75185, Uppsala, Sweden