1. Faculty of Medicine, Riga Stradinš University, Riga, Latvia
2. Faculty of Medicine, ‘Carol Davila’ University of Medicine and Pharmacy, Bucharest, Romania
3. Faculty of Medicine, Teaching University Geomedi LLC, Tbilisi, Georgia
4. Faculty of Medicine, Vilnius University, Vilnius, Lithuania
5. Faculty of Medicine, Lille University School of Medicine, Loos, Lille, France
6. Joint Electron Microscopy Laboratory, Institute of Anatomy and Anthropology, Riga Stradinš University, Riga, Latvia
7. Department of Biology and Microbiology, Riga Stradinš University, Riga, Latvia