2.2. Plasma lipids and apoM levels. Plasma apoM concentration was estimated by dot-blot analysis using monoclonal mouse anti-human apoM antibody (ABNOVA, Taipei, Taiwan) following previously established protocols [14, 15] . Recombinant human apoM (ABNOVA, Taipei, Taiwan) was used as protein standard after serial dilution. The mean signal densities of each specimen and protein standards in triplicate measures were determined by ImageJ 1.42q software (http://rsbweb.nih.gov/ij/). ApoM concentration was derived from the standard curves developed using the recombinant apoM protein.