1. Uzdrowisko Ustroń, Grupa American Heart of Poland, Ustroń, Poland
2. Department of Biochemistry and Medical Genetics, Faculty of Health Sciences in Katowice, Medical University of Silesia, Katowice, Poland
3. Department of Gastroenterology and Hepatology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland