[Determination of the high density lipoprotein (HDL) cholesterol in blood serum. Comparison of 3 methods: ultracentrifugation and precipitations (author's transl)].

Three methods of assaying the high density lipoprotein cholesterol were applied simultaneously to a hundred of human sera: ultracentrifugation, precipitation by concavalin A and phosphotungstic acid. The obtained results were compared by statistical means: it was shown that the three procedures were equivalent. Some of their analytical features are discussed.

[Comparative study of total cholesterol, HDL cholesterol, LDL + VLDL cholesterol. Two methods: precipitation by concanavalin A and ultra centrifugation (author's transl)].

The authors determined in 3 populations (37 controls, 59 asymptomatic hyperlipemias, and 20 cases of arterial hyperlipemia) the total cholesterol, the HDL cholesterol and the LDL + VLDL cholesterol and their ratio by two methods : precipitation by concanavalin A and ultracentrifugation (AirFuge). These various lipid parameters were compared between 3 populations in order to determine their more or less discriminant character; furthermore, was established the degree of correlation between the results obtained by precipitation with concanavalin A and by ultracentrifugation. The results show : firstly, that the LDL + VLDL was significantly higher and the ratio HDL/LDL + VLDL significantly lower in hyperlipemia and in arterial disease compared with controls ; the HDL was significantly lower in arterial disease than in controls.

[Modifications of peptide hydroxyprolinuria during Paget's disease and osteoma (author's transl)].

The values of hydroxyprolinuria were determined in 314 cases of Paget's disease and 91 cases of osteoma. During Paget's disease, the values found were related to the degree of the bony disorder. A more detailed study of the hydroxyproline polypeptides was undertaken, comparatively in a few cases of these two diseases.

[Type IIb primary hyperlipoproteinemia. An homogenous series of 412 cases].

On the basis of a homogeneous series of 412 cases of type IIb primary hyperlipoproteinaemia, the authors compare their experience with findings in the literature. The prevalence of this type of hyperlipoproteinaemia in the general population has been underestimated at 3%. Biological diagnosis remains simple (identification of a double and distinct excess in beta and pre beta lipoproteins).