2.5. Biochemical Analysis
SEPARATION
After sampling, 5 mL of venous blood was used for serum separation. Serum samples were stored at −20 °C until the day of analysis. The ELISA method was used for analyzing the activity of myeloperoxidase (MPO) and acetylcholinesterase enzymes (AchE) in Iranian subjects (ELISA Kit, Eastbiopharm, Hangzhou, Zhejiang, China).