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F Mainard

Publications and source records attributed to F Mainard.

36 records · Page 2Linked to original sources
PubMed1988

Variations in the composition of low- and high-density lipoproteins during the acute phase of myocardial infarction.

We analyzed correlations between apolipoprotein B (apo B), cholesterol and phospholipids (preponderant lipids) in low-density lipoproteins (LDL) as well as between apolipoprotein A1 (apo A1) and these same lipids in high-density lipoproteins (HDL), during the acute phase of myocardial infarction. In LDL, a very elevated and stable correlation (r) was observed between these parameters, and the coefficients of regression (b) did not differ significantly during the period studied. In HDL, there was a decrease in r and b values from day 1 to day 2, then an increase after day 2. We hypothesize that these disturbances in HDL composition may be due to a greater endocytosis of LDL at day 2, leading to intracellular increase in cholesterol and phospholipids. Part of these lipids could be taken up by HDL molecules, causing a transient overload.

Aged↗
PubMed1987

Are 'precipitated LDL' really low density lipoproteins?

Cholesterol, phospholipid and Apo B levels were determined in low density lipoproteins (LDL) precipitated by amphipathic polymers (Biomérieux kit, Marcy-l'Etoile, France) and compared to those of ultracentrifuged LDL. For 113 sera (triglyceride level less than 4.5 mmol/l, absence of very low density lipoproteins-remnants) LDL-cholesterol values were significantly higher (p less than 0.001), and those of LDL-phospholipids (p less than 0.001) and LDL-Apo B (p less than 0.005) significantly lower. The correlations between the 3 constituents studied gave statistically different regression coefficients for the two methods. It is likely that discrepancy in results is due to the effect of ultracentrifugation and precipitation removing from the lipoprotein spectrum different sections which nonetheless have some common physicochemical or immunological properties. It would seem that the term 'LDL' is inappropriate to designate these precipitated lipoproteins.

Apolipoproteins B↗
PubMed1986

[Cholesterol, phospholipid and apoB composition of LDL: comparison of precipitation and ultracentrifugation methods].

Cholesterol, phospholipid and apoB levels were determined in LDL precipitated by amphiphatic polymers (Biomérieux kit, Marcy-l'Etoile, France). Intra-assay and inter-assay analysis performed on 4 serum pools were satisfactory. For 113 sera (triglyceride level less than 4.5 mmol/l, absence of VLDL-remnants), the 3 variables were well correlated with those of centrifuged LDL (0.93 less than r less than 0.98); however, LDL-cholesterol values were significantly higher (p less than 0.001), and those of LDL-phospholipids (p less than 0.001) and LDL-apoB (p less than 0.005) significantly lower. The correlations between the 3 constituents studied gave statistically different regression coefficients for the two methods. It is concluded that these precipitated lipoproteins do not seem to correspond to LDL but to "LDL markers".

Apolipoproteins B↗
PubMed1985

Study of a myoglobin test in patients hospitalized for suspected myocardial infarction.

An immunoagglutination latex test was studied in comparison with a plasma myoglobin radioimmunoassay in 103 subjects with suspected myocardial infarction. The test provided an early and reliable indication of raised plasma myoglobin (greater than 85 micrograms/l), a biochemical marker for the early phase (12 h) of myocardial infarction. The diagnostic values (sensitivity and specificity) studied over a 36 h period were the same as those for the plasma myoglobin assay. The sensitivity was similar to that of creatine kinase activity and better than that of the creatine kinase MB/creatine kinase ratio; the lower specificity was due to false-positive results in some subjects with angina. The myoglobin test, which provides rapid results, may be substituted in early diagnosis of myocardial infarction for the plasma myoglobin assay which is unsuitable for emergency analysis.

Aged↗
PubMed1984

[Blood and plasma hyperviscosity in primary hyperlipidemia].

Plasma and blood viscosities were studied in 15 hyperlipidemic (HLP) patients and in 10 healthy volunteers. Viscosities were measured at 25 degrees C using a couette type viscosimeter. Plasma and blood viscosities were significantly increased in HLP patients. This increase in viscosity was better correlated with triglyceride than with cholesterol level. This result might partially account for the clinical differences observed between hypertriglyceridemia and hypercholesterolemia.

Blood Viscosity↗
PubMed1978

[Mechanism of induction of tyrosine in rat liver by phenothiazine derivatives and related chemical compounds].

Increase of hepatic tyrosine-alpha-ketoglutarate transaminase is observed in Rats (Wistar strain) after intraperitoneal administration of tricyclic compounds (phenothiazin and related structure derivatives). This is an induction process: actinomycine D inhibits this effect. This action is not mediated by glucocorticoids: induction persists in adrenalectomized Rats. The mechanism of action is different too: additive effects are found after simultaneous injection of glucocorticoid and tricyclic drug.

Adrenal Glands↗
PubMed1978

[Induction of hepatic tyrosine transaminase in rats by phenothiazine derivatives and analogs].

We have showed induction of tyrosine-alpha-ketoglutarate transaminase in hepatic cytosol of Rats (Wistar strain) five hours after intraperitoneal administration of tricyclic compounds (phenothiazine, iminodibenzyl, thioxanthene, thiophenylpyridylamin, dibenzocycloheptadiene, dibenzoxepin derivatives). Chemical structure of these molecules is very important: sulfur atom (phenothiazine, thioxanthene), some substituants like chlorine (chlorpromazine, chlorprothixene) and 2'-dimethylaminopropyl chain (promethazine) increase this inductive effect.

Animals↗
PubMed1977

[Study of magnesium level in myocardium and aorta tissues from subjects free of ishemic necrosis (author's transl)].

Before carrying out a study on the levels of magnesium in the myocardium and the aorta in subjects who had died of coronary thrombosis, we determined the reference levels of magnesium in the right and left ventricles and in the aorta of sixteen normal subjects. The samples were homogenized and digested with nitric acid/hydrochloric acid mixture before the measurement itself was made; this was carried out by atomic absorption spectrophotometry. The magnesium values are expressed in microng/g of wet tissue, in mg/g of tissular proteins, in mg/ of total lipids in the aortic wall. The differences between the concentrations of proteins or magnesium in the left and right ventricles are significant magnesium in the left and right ventricles are significant (P less than 0,001). They probably derive from anatomic and physiological differences. We have found a correlation which is significantly positive between magnesium level and protein level in the ventricle. In the aorta, the results for proteins, lipids and magnesium are extremely dispersed because of the heterogeneous nature of biochemical composition of this tissue according to age and area which it has been taken from.

Aorta↗
PubMedDate not supplied

[Circadian rhythms in man. Their incidence in endocrinology (author's transl)].

The authors, after a classification of the main biological rhythms, mention the parameters of the circadian rhythm deduced by mathematical analysis of so-called "Cosinor". They then devote their study to the main hormones, the secretion of which depends on circadian periodicity. They emphasize the effect that their biorhythm has on the value of plasma concentrations depending on the time of sampling. They suggest standardisation of this time in drawing up international norms.

Adolescent↗