1. Metabolic, Departments of the L. Boltzmann Institute for Metabolic Diseases and Nutrition, City Hospital Vienna-Lainz Vienna, Austria
2. Surgical, Departments of the L. Boltzmann Institute for Metabolic Diseases and Nutrition, City Hospital Vienna-Lainz Vienna, Austria
3. Biomedical Engineers Group Siemens AG, Erlangen, Germany
4. Pharma-Research Hoechst AG, Frankfurt, Germany