1. Gerontology Research Center, School of Health Sciences, University of Tampere, Finland.
2. Gerontology Research Center, Department of Health Sciences, University of Jyväskylä, Finland.
3. Department of Health, Functional Capacity and Welfare, National Institute for Health and Welfare, Turku, Finland.
4. Science Center of Pirkanmaa Hospital District, Tampere, Finland.
5. Microbiology and immunology, University of Tampere, School of Medicine, Finland.
6. Fimlab Laboratories Ltd., Pirkanmaa Hospital District, Finland.
7. Department of Clinical Chemistry, University of Tampere, School of Medicine, Tampere, Finland.