1. Endocrine Unit, Specialised Diagnostic Centre, Institute for Medical Research, National Institutes of Health, Ministry of Health Malaysia , 50588 Kuala Lumpur , Malaysia
2. Clinical Research Centre, Hospital Tuanku Fauziah, Ministry of Health Malaysia , 01000 Perlis , Malaysia
3. College of Biomedical Sciences, Larkin University , Miami, FL 18301 , USA
4. Biochemistry Unit, Specialised Diagnostic Centre, Institute for Medical Research, National Institutes of Health, Ministry of Health Malaysia , 50588 Kuala Lumpur , Malaysia