1. Thomas Jefferson University, Philadelphia, PA, USA
2. Kantonsspital Baselland, Liestal, Switzerland
3. University of Pennsylvania, Philadelphia, PA, USA
4. Clinica Universitaria de Navarra, Navarra, Spain
5. Cleveland Clinic Foundation, Cleveland, OH, USA
6. Keck School of Medicine of the University of Southern California, Los Angeles, CA, USA
7. Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
8. Wayne State University, Detroit, MI, USA