1. Cardiological Outpatients, Medicor, Myszków, Poland
2. Department of Pediatrics, SMDZ in Zabrze, SUM in Katowice, Poland
3. Department of Medical and Molecular Biology, SMDZ in Zabrze, SUM in Katowice, Poland
4. Pediatric Nephrology Ward, Public Clinical Hospital, Zabrze, Poland