Logistic discriminant analysis of lipids and apolipoproteins in a population of coronary bypass patients and the significance of apolipoproteins C-III and E.

The lipid and apolipoprotein states of 74 men (mean age 49.96 +/- 5.9 years) were studied 24 h before coronary bypass surgery and their results were compared with those of a control group of 78 men (mean age 48.88 +/- 5.41 years). Apolipoproteins C-III (apo C-III) and E (apo E) were determined in particles with (LpB) and without (nonLpB) apo B separated using a concanavalin A reagent. Apo C-III was significantly increased in LpB particles (P less than 0.001), and apo E in LpB (P less than 0.001) and nonLpB (P less than 0.001) particles. The significant variables selected in logistic discriminant stepwise analysis were total cholesterol/HDL-cholesterol, apo E-nonLpB and apo C-III-LpB. This last parameter, which is more discriminant than triglycerides, provides a more specific indication of dyslipoproteinemia in coronary bypass patients; in association with the other two variables, it significantly improved the percentage of correctly classified individuals.

[Serum myoglobin: evaluation of two immunolatex methods. Comparison with a radioimmunoassay method]. / Myoglobine sérique: évaluation de deux méthodes aux immunolatex. Comparaison avec une méthode radio-immunologique.

Latex immunoturbidimetric (ITA) and immunonephelemetric (INA) assays, were evaluated and compared to a radioimmunological assay (RIA) for the determination of serum myoglobin. Within-run and between-run assays and accuracy and linearity studies gave satisfactory results, very similar to those of RIA. Results were closely correlated with those of RIA for 100 samples of up to 2,000 micrograms/l (correlation coefficients respectively 0.96 and 0.97 for ITA and INA). Reference values (150 men and 150 women; range 20-65 years) were determined and expressed in percentiles. It is concluded that the two latex immunologic assays facilitate laboratory myoglobin evaluation (no radioactive material, short performance time). ITA is more suitable for emergency analysis and INA is more convenient for serial analysis and particular samples (presence of hemoglobin or chylomicrons).

Study of lipoprotein particles LpAI and LpAI:AII in patients before coronary bypass surgery.

Lipids, apolipoproteins, and LpAI and LpAI:AII particles were studied in 43 men (mean age 51, SD 7, years) 24 h before their coronary bypass surgery and in 54 control men (mean age 46 SD 9, years). LpAI and LpAI:AII were analyzed by electroimmunodiffusion and by a noncompetitive enzyme-linked immunoassay, respectively. Concentrations of LpAI and LpAI:AII in the bypass patients were significantly lower (P less than 0.001) than those in the controls. Apolipoprotein AI was significantly correlated with LpAI (P less than 0.001) and LpAI:AII (P less than 0.01) in controls, but only with LpAI:AII (P less than 0.001) in bypass patients. Discriminant analysis between controls and patients showed apolipoprotein AI to be the most powerful discriminant factor; the addition of LpAI and LpAI:AII did not improve discriminant power. We conclude that the determination of LpAI and LpAI:AII particles reflects metabolic disorders in patients but does not significantly influence the discrimination of such patients into risk groups.