1. Faculty of Medicine and Life Sciences, Hasselt University, Martelarenlaan 42, B-3500 Hasselt, Belgium
2. Applied and Analytical Chemistry, NMR Group, Institute for Materials Research (Imo-Imomec), Hasselt University, Agoralaan 1, B-3590 Diepenbeek, Belgium
3. Department of Respiratory Medicine, Ziekenhuis Oost-Limburg, Synaps Park 1, B-3600 Genk, Belgium
4. Department of Respiratory Medicine, University Hospital Leuven, Herestraat 49, B-3000 Leuven, Belgium
5. Department of Respiratory Medicine, Algemeen Ziekenhuis Vesalius, Hazelereik 51, B-3700 Tongeren, Belgium
6. Department of Nuclear Medicine, Ziekenhuis Oost-Limburg, Synaps Park 1, B-3600 Genk, Belgium