1. Pantarhei Bioscience , 3700 AL Zeist , The Netherlands
2. Terminal 4 Communications , 1217 SK Hilversum , The Netherlands
3. Andros Clinics , 6842 CV Arnhem , The Netherlands
4. Institute of Reproductive and Developmental Biology, Imperial College London , London SW7 2AZ , UK
5. Division of Urology, University Clinic Saint-Luc , 1200 Brussels , Belgium