1. Leiden/Amsterdam Center for Drug Research, Department of Pharmacochemistry, Faculty of Chemistry, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
2. Department of Clinical Animal Laboratory, Faculty of Medicine, Vrije Universiteit, Van der Boechorststraat 7, 1081 HV Amsterdam, The Netherlands
3. Data Sciences International, 4211 Lexington Avenue North, St Paul, MN 55126-6164, USA