1. Department of Clinical Biochemistry, College of Medicine and Allied Sciences, King Abdulaziz University, P.O. Box 9029, Jeddah, Saudi Arabia.
2. King Fahd Medical Research Center, College of Medicine and Allied Sciences, King Abdulaziz University, P.O. Box 9029, Jeddah, Saudi Arabia.
3. Department of Surgery, College of Medicine and Allied Sciences, King Abdulaziz University, P.O. Box 9029, Jeddah, Saudi Arabia 21413.
4. Department of Biochemistry, University of Oxford, South Parks Road, Oxford OXI 3QU, U.K.