A. Oxidative balance ratio: All samples will be analyzed for total hydroperoxides (TH) and biological antioxidant capacity (BAP) using the Free Radical Analytical System (FRAS4 analyzer, H&D SRL, Parma, Italy) as described in our previous study. TH represents the total of radical O2 metabolites produced by peroxidation of protein, lipids and amino acids, measures oxidative damage and serves as a biomarker of overall free radical attack. BAP measures both endogenous and exogenous antioxidative capacity of serum to reduce oxides by inactivating, and eliminating free radicals and reactive O2 species. BAP by exploiting the chemical principle of the well-known ferric reducing ability of plasma provides a reliable measure of biological antioxidant potential of plasma. To estimate the global balance between oxidative stress and antioxidant potential, the oxidative balance ratio (BAP/TH) will be calculated.