1. Anatomy Department and Stem Cell Unit, College of Medicine, King Saud University, Riyadh, KSA
2. Pathology Department, College of Medicine, King Saud University, Riyadh, KSA
3. Physiology Department, College of Medicine, King Saud University, KSA
4. Pharmacology and Toxicology Department, Faculty of Pharmacy, King Saud University, Riyadh, KSA
5. Genetics and Cytology Department, National Research Centre, Cairo, Egypt
6. Common First Year Deanship, King Saud University, Riyadh, KSA
7. Pharmacology and Toxicology Department, College of Pharmacy, Zagazig University, Zagazig, Egypt
8. Biochemistry Department, College of Science, King Saud University, Riyadh, KSA