1. Faculty of Medicine, Rīga Stradiņš University (RSU), LV-1007 Riga, Latvia
2. Department of Human Physiology and Biochemistry, Rīga Stradiņš University (RSU), LV-1007 Riga, Latvia
3. Department of Dermatology and Venerology, Rīga Stradiņš University (RSU), LV-1010 Riga, Latvia