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Biomedical subjects

G Durand

Publications and source records attributed to G Durand.

At least 253 records · Page 14Linked to original sources
PubMed1984

Zone immunoelectrophoresis assay applied to alpha 1-acid glycoprotein secretion by isolated rat hepatocytes.

A method for measuring proteins in low concentrations applying the zone immunoelectrophoresis assay is reported. The low detection limit makes it possible to measure alpha 1-acid glycoprotein in rat serum and also to quantify the secretion of this protein after concentration of the incubation media containing less than 10(7) isolated rat hepatocytes. The method is simple and consumes very small quantities of antiserum.

Animals↗
PubMed1984

An immunochemical procedure to evaluate the degree of desialylation of alpha 1-acid glycoprotein in rat serum.

When radial immunodiffusion (RID) and electroimmunodiffusion (EID) were used for the determination of rat alpha 1-acid glycoprotein (alpha 1-AGP) a significant discrepancy in the results was encountered depending on the degree of sialylation. When alpha 1-AGP was desialylated, the amounts estimated by EID were much lower than those actually present as assayed by the RID method. The relationship between the percentage of desialylation of alpha 1-AGP and the percentage of its underestimation by EID relative to RID was determined and a calibration curve was plotted to evaluate the degree of desialylation of rat alpha 1-AGP. When compared to other procedures (rat membrane inhibition assay and isoelectrofocusing), the proposed method was easier to perform and allowed the specific evaluation of the degree of undersialylation of the glycoprotein.

Animals↗
PubMed1984

Lipogenesis from U14C lactate in obese Zucker rat hepatocytes. Effect of albumin-bound oleate.

Lipogenesis from U(14C) lactate was studied in hepatocytes isolated from obese Zucker rats (fa/fa) their lean littermates (Fa/?) and Sprague Dawley rats. The distribution of radioactive carbon between the glycerol and the fatty acid moieties of the acylglycerols were studied. Radioactive lactate was better utilized for glycerol formation than it was for fatty acid formation in the obese rats. However, when oleate was added to the hepatocytic incubation medium, radioactive lactate was preferentially incorporated into the fatty acid moiety of the acylglycerols. Zucker obesity classified as a "metabolic obesity" by Meyer (1) depends upon abnormalities in carbohydrate metabolism associated with increased lipogenesis. This might be explained by biochemical shifts in the utilization of nutrients (2). Among the nutrients, lactate seems to be a better source of carbon than glucose for lipid synthesis (3). It has been shown that there is an increased hepatic portal blood concentration of lactate several hours after eating: about 4 mM in Wistar rats (4) and 10-15 mM in obese Zucker rats (3). We are interested in determinating the incorporation of carbon from lactate either into glycerol or into fatty acyl moieties of hepatic acylglycerols, and in determining the influence of exogenous fatty acids on acylglycerol synthesis, since a high level of circulating fatty acids in Zucker obese rats has been reported (5). Our purpose was to determine the incorporation of lactate into glycerol and fatty acyl moieties of acylglycerols, under the influence of oleate. Hepatocytes were isolated from ad libitum fed obese Zucker rats (fa/fa), their lean littermates (Fa/?) and Sprague-Dawley rats (SD). Incorporation of lactate was studied for three hours, in order to exclude short-term regulation effects and to allow oleate to be distributed into all cellular compartments.

Albumins↗
PubMed1984

Asialoorosomucoid degradation by normal and diabetic rat hepatocytes.

Using high concentrations of extracellular [3H]asialoorosomucoid we obtained the steady-state level of [3H]asialoorosomucoid endocytosis by isolated hepatocytes from normal and streptozotocin diabetic rats. At the steady-state of the overall reaction, the intracellular amount of [3H]asialoorosomucoid did not change with time, the apparent overall rate of [3H]asialoorosomucoid degradation was close to that of [3H]asialoorosomucoid internalization, in both normal and diabetic rat hepatocytes. Although in diabetic cells the intracellular amount of [3H]asialoorosomucoid was about three-times lower than in normal cells, the same fraction of intracellular asialoorosomucoid was degraded per time interval by both normal and diabetic cells. The apparent first-order rate constant of steady-state degradation was about 0.011 min-1 for both normal and diabetic cells. In diabetic rat hepatocytes, the decrease of the clearance of serum asialoglycoproteins was directly correlated to the variation of cell surface receptor number, without any modification of internalization and degradation steps.

Animals↗
PubMed1984

[Tubal sterility: fertilization in vitro or microsurgery].

In this review paper the respective places of microsurgery and in vitro fertilization in the treatment of tubal infertility are evaluated. The best and current results of the two methods are compared and their future is considered. Most of the indications for microsurgery remain, while some (e.g. poor prognosis salpingostomy, repeated tuboplasty, tubal transplantation) require discussion and new ones are appearing. The advent of in vitro fertilization has introduced some technical changes in surgery of the ovaries and surrounding tissues and has given rise to new techniques. It has also modified the initial investigations in infertile women and the use of pre-operative and second-look laparoscopy. It has exerted little influence on microsurgeons specialized in problems of reproduction but has obliged their teams to be reorganized on a multidisciplinary basis in order to cope with new techniques.

Fallopian Tube Diseases↗
PubMed1984

Alterations in the fatty acid composition of rat brain cells (neurons, astrocytes, and oligodendrocytes) and of subcellular fractions (myelin and synaptosomes) induced by a diet devoid of n-3 fatty acids.

Rats were fed through four generations with a semisynthetic diet containing 1.0% sunflower oil (6.7 mg/g n-6 fatty acids, 0.04 mg/g n-3 fatty acids). Ten days before mating, half of the animals received a diet in which sunflower was replaced by soya oil (6.6 mg/g n-6 fatty acids, 0.8 mg/g n-3 fatty acids) and analyses were performed on their pups. Fatty acid analysis in isolated cellular and subcellular material from sunflower-fed animals showed that the total amount of unsaturated fatty acids was not reduced in any cellular or subcellular fraction (except in 60-day-old rat neurons). All material from animals fed with sunflower oil showed an important reduction in the docosahexaenoic acid content, compensated (except in 60-day-old rat neurons) by an increase in the n-6 fatty acids (mainly C22:5 n-6). When comparing 60-day-old animals fed with soya oil or sunflower oil, the n-3/n-6 fatty acid ratio was reduced 16-fold in oligodendrocytes, 12-fold in myelin, twofold in neurons, sixfold in synaptosomes, and threefold in astrocytes. No trienes were detected. Saturated and monounsaturated fatty acids were hardly affected. This study provides data on the fatty acid composition of isolated brain cells.

Animals↗
PubMed1983

[Veralipride and menopause].

Twenty post-menopausal women (10 natural and 10 surgical menopauses) with climateric manifestations consisting mainly in hot flushes were given veralipride. Overall satisfactory results obtained in two-thirds of cases evidence the value of tis non-hormonal therapy, especially in cases of natural menopause which responded consistently. Clinical tolerance of veralipride proved satisfactory. Biological investigations (total and differential blood cell counts, glucid and lipid metabolism, BUN, transaminases) before and after three twenty-day courses of veralipride showed no modifications. Hormonal assays done in four patients showed no action of veralipride on FSH and LH.

Castration↗
PubMed1983

Diabetes-induced variation in hepatic binding protein.

The total capacity of hepatocytes to bind asialoorosomucoid was measured on normal and streptozotocin diabetic rats. 4 days after the streptozotocin injection, a slight decrease of total receptor concentration was observed while a more marked reduction of cell surface receptor occurred. In animals sacrificed 11 days after the streptozotocin injection, the total capacity of hepatocytes to bind asialoorosomucoid was about 70% of the normal level.

Animals↗
PubMed1983

Membrane lipids of hepatocytes, Kupffer cells and endothelial cells.

The membrane lipid composition of isolated hepatocytes, Kupffer cells and endothelial cells was determined. The hepatocytes are characterized by a lower quantity of gangliosides, cholesterol, sphingomyelin and a reduced cholesterol/phospholipid molar ratio when compared to the two other liver cell types. The main gangliosides of Kupffer and endothelial cells are the GM3 species, and those of hepatocytes are of the polysialogangliosides species.

Animals↗
PubMed1983

in vivo Ageing of human erythrocytes and cell-surface labeling by metaperiodate and sodium borotritide.

Young and old human erythrocytes, separated in vitro according to age, were labeled at the surface-sialic acid residues by sodium periodate and borotritide treatment. No qualitative difference was observed between the sialic acid derivatives of young- and old-erythrocyte membranes. The number of labeled residues was significantly decreased in the in vivo aged erythrocytes (12 +/- 2.8 X 10(6); n = 8) when compared to the young ones (19.4 +/- 2.8 X 10(6); n = 8). Analysis of the labeled glycoproteins by sodium dodecyl sulfate gel-electrophoresis showed that this decrease affects the PAS-1, PAS-4, PAS-2, and PAS-3 bands (glycophorins A and B) of the old-erythrocyte membranes.

ABO Blood-Group System↗
PubMed1983

Relative contribution of the main tissues and organs to body fatty acid synthesis in the rat.

Tritiated water was used to measure the rate of fatty acid synthesis in the main tissues and organs of 7-week old Wistar male rats in order to determine the relative contribution of each tissue to body fatty acid synthesis. We reached the following conclusions: (a) the liver is the main site of fatty acid synthesis, it alone synthesizes 42% of the newly synthesized fatty acids in the body. (b) The dissectable white adipose tissues synthesize 27% of the fatty acids in the body. This group of tissues is heterogeneous because the mesenteric adipose tissue alone contains 40% of the labeled fatty acids present in the white adipose tissues. (c) Besides the intestines, organs other than the liver play a negligible role (2% of the total) in fatty acid synthesis. (d) The skin contributes 7% of the body fatty acid synthesis. (e) The rest of the carcass, essentially composed of the musculature and the skeleton, contributes 18% of body fatty acid synthesis and accounts for 33% of the extrahepatic tissue fatty acid synthesis.

Adipose Tissue↗
PubMed1983

Lipogenic capacity and relative contribution of the different tissues and organs to lipid synthesis in male rat.

The rates of 3H2O incorporation into total lipids and fatty acids were measured in vivo in the different organs and tissues of 7-week old male Wistar rats to compare the lipogenic capacity of those organs and tissues and to determine their relative contributions to body lipid synthesis. Our results were the following; (1) liver was the major site of the synthesis of total lipids and fatty acids (37 and 42%, respectively, of body synthesis); (2) white adipose tissues synthesized about 24% of the total lipids; mesenteric adipose tissue alone synthesizing 40% of the fatty acids produced in dissectable white adipose tissues; (3) skin showed low lipid synthesis but played an appreciable role in that synthesis (8% of the total) due to its large contribution to total body weight; (4) other organs (excluding liver) showed low lipid synthesis; however, that of the small intestine was 1-2% of body synthesis; (5) the rest of the carcass (mainly musculature and skeleton) contributed 25% to body lipid synthesis. The putative roles of the different tissues and organs in adipose tissue development have been discussed.

Adipose Tissue↗
PubMed1983

Effects of age and weaning on enzyme activities of abomasum and pancreas of the lamb.

The effect of age and weaning on enzyme activities of abomasum and pancreas of the lamb was studied. Sixty-nine lambs were either maintained at the preruminant stage until 42 days of age or weaned between 20 and 30 days. They were slaughtered between birth and 100 days, and the mucosa of their abomasum and their pancreas were collected. At 2 days of age there was a threshold of glandular growth and of development of enzyme secretory potentialities. Pancreas showed an extensive hyperplasia without growth until day 2; its weight increased after day 7 but only by hypertrophy. Quantities of gastric enzymes in relation to empty live weight increased between birth and 2 days, but that of chymosin then decreased, whereas pepsin did not change significantly; effects of weaning were similar. The evolution of pancreatic enzyme activity was usually the reverse of that of chymosin; however, trypsin activity was low at birth and that of colipase did not increase at weaning. The ratio of colipase to lipase was always higher than 1, showing that lipase always was saturated in the lamb. The pancreas seemed to take over the secretion of abomasal proteolytic enzymes. Potentialities of enzyme digestion appeared to be influenced mainly by the age or weight of the animal; these potentialities were minimal for at least several days during the first neonatal week and, if there was enzymatic adaptation to the amounts of the ingested substrate, it did not occur rapidly.

Abomasum↗
PubMed1983

[Predicting ovulation by detecting the preovulatory rise of estrogens and LH in the urine].

The preovulatory LH surge induces final maturation of the ovocyte which makes it suitable for in vitro fertilization. The spontaneous LH peak can be detected in blood or in the urine. Whatever the method of determination, the diagnosis of the triggering LH surge can be done only on strict criteria. This work defines these criteria when urinary Higonavis is used: a rise in the plus signs in two successive samples or a positive result in urine diluted fourfold.

Estrogens↗
PubMed1982

[Plasma level monitoring of psychotropic drugs in children. II -- Antidepressants (author's transl)].

Children and young adolescents with either depressive syndromes or enuresis were treated with clomipramine for periods of 1 to 9 months. Plasma concentrations of the drug and of its demethylated metabolite were monitored and compared with clinical effects. In children, clomipramine proved rapidly absorbed by the oral route, and its rate of distribution seemed to be related to age since the dose-concentration ratio was lower in the youngest subjects. There was a clear correlation between side-effects and clomipramine levels but not demethyl-chlorimipramine levels. In enuresis, a therapeutic effect was obtained with clomipramine levels of 20 to 60 ng/ml; lower levels were associated with ineffectiveness and higher levels with side-effects. The relationship between daily doses and plasma concentrations varied considerably from one patient to another but was almost constant in the same individual. The results obtained underline the usefulness of routinely monitoring antidepressant plasma levels in children.

Adolescent↗