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71.
The role of lipid components of the diet in the regulation of the fatty acid composition of the rat liver endoplasmic reticulum and lipid peroxidation 总被引:5,自引:2,他引:3 下载免费PDF全文
The fatty acid compositions of the lipids and the lipid peroxide concentrations and rates of lipid peroxidation were determined in suspensions of liver endoplasmic reticulum isolated from rats fed on synthetic diets in which the fatty acid composition had been varied but the remaining constituents (protein, carbohydrate, vitamins and minerals) kept constant. Stock diet and synthetic diets containing no fat, 10% corn oil, herring oil, coconut oil or lard were used. The fatty acid composition of the liver endoplasmic reticulum lipid was markedly dependent on the fatty acid composition of the dietary lipid. Feeding a herring-oil diet caused incorporation of 8.7% eicosapentaenoic acid (C20:5) and 17% docosahexaenoic acid (C22:6), but only 5.1% linoleic acid (C18:2) and 6.4% arachidonic acid (C20:4), feeding a corn-oil diet caused incorporation of 25.1% C18:2, 17.8% C20:4 and 2.5% C22:6 fatty acids, and feeding a lard diet caused incorporation of 10.3% C18:2, 13.5% C20:4 and 4.3% C22:6 fatty acids into the liver endoplasmic-reticulum lipids. Phenobarbitone injection (100mg/kg) decreased the incorporation of C20:4 and C22:6 fatty acids into the liver endoplasmic reticulum of rats fed on a lard, corn-oil or herring-oil diet. Microsomal lipid peroxide concentrations and rates of peroxidation in the presence of ascorbate depended on the nature and quantity of the polyunsaturated fatty acids in the diet. The lipid peroxide content was 1.82±0.30nmol of malonaldehyde/mg of protein and the rate of peroxidation was 0.60±0.08nmol of malonaldehyde/min per mg of protein after feeding a fat-free diet, and the values were increased to 20.80nmol of malonaldehyde/mg of protein and 3.73nmol of malonaldehyde/min per mg of protein after feeding a 10% herring-oil diet in which polyunsaturated fatty acids formed 24% of the total fatty acids. Addition of α-tocopherol to the diets (120mg/kg of diet) caused a very large decrease in the lipid peroxide concentration and rate of lipid peroxidation in the endoplasmic reticulum, but addition of the synthetic anti-oxidant 2,6-di-t-butyl-4-methylphenol to the diet (100mg/kg of diet) was ineffective. Treatment of the animals with phenobarbitone (1mg/ml of drinking water) caused a sharp fall in the rate of lipid peroxidation. It is concluded that the polyunsaturated fatty acid composition of the diet regulates the fatty acid composition of the liver endoplasmic reticulum, and this in turn is an important factor controlling the rate and extent of lipid peroxidation in vitro and possibly in vivo. 相似文献
72.
Constantinos J. Limas Catherine Limas 《Biochimica et Biophysica Acta (BBA)/General Subjects》1978,540(3):543-546
Sialyltransferase activity was compared in homogenates and microsomal fractions from hearts of cardiomyopathic Syrian hamsters and age-matched normal controls. Decreased enzymatic activity was found in cardiomyopathic hamsters, with most of the decline occurring between the first and second month of life; it was associated with a parallel fall in mcirosomal sialic acid content. Since membrane-bound sialic acid may control Ca2+ exchangeability in cardiac muscle (and, indirectly, tension development), these results provide a biochemical basis for the development of cardiac failure in the Syrian hamster. 相似文献
73.
Catherine Grenot Claude-Yves Cuilleron 《Biochemical and biophysical research communications》1977,79(1):274-279
An electrophoretic elution procedure of antibodies retained on affinity columns is described. It afforded a 60% recovery of the binding activity of a high affinity (Ka ~ 1010 M?1) antiserum to 5α-dihydrotestosterone retained on antigen-linked Sepharose 4B affinity columns. These purified unbound antibodies, (Ka ~ 1010 M?1) when applied again on identical antigen-linked affinity columns, were all retained and totally recovered after a new electrophoretic elution. Comparable results were obtained by elution with 1M NH4OH.The residual 40% binding activity remaining on the antigen-linked Sepharose gel after electrophoretic elution was totally recovered by elution with an excess of 5α-dihydrotestosterone. It corresponded to antibodies of higher affinity (Ka ~ 1011 M?1). On the other hand the residual 40% fraction of antibodies resistant to NH4OH elution was denaturated. 相似文献
74.
Gerald J. Putterman Badaruddin Shaikh Margarette R. Hallmark Cheryl G. Sawyer Catherine V. Hixson Fulvio Perini 《Analytical biochemistry》1979,98(1):18-26
Procedures are presented for the simultaneous analysis of hypoxanthine, xanthine, allopurinol, oxipurinol, and uric acid in standard mixtures and physiological fluids using gas chromatography (gc) or high-pressure liquid chromatography (hplc). Excellent correlation was obtained between the two methods for hypoxanthine, xanthine, oxipurinol, and uric acid. There are advantages and disadvantages to both methods. hplc requires no prior derivatization, uses isocratic elution with a buffer containing no organic solvent, and has 50- to 100-fold greater sensitivity than gc. Simpler methods of prepurification, readily adapted to clinical laboratories, can be used for hplc analysis. Although substances that are found in some urine samples from cancer patients interfere with hplc, separations by gc are not affected by these substances. 相似文献
75.
Distribution of the Luminous Bacterium Beneckea harveyi in a Semitropical Estuarine Environment 总被引:8,自引:6,他引:2 下载免费PDF全文
Bioluminescent bacteria were found in the water column, sediment, shrimp, and gastrointestinal tract of marine fishes from the semitropical estuarine environment of the East Lagoon, Galveston Island, Tex. Populations in the water column decreased during cold weather while sedimentary populations persisted. The highest percentages of luminous organisms were isolated from the gastrointestinal tract of marine fishes, where they persisted during 5 days of starvation. The presence of chitin temporarily increased intestinal populations. All isolates were Beneckea harveyi, whose natural habitat appears to be the gut of fishes and whose free-living reservoir appears to be marine sediments. 相似文献
76.
Early ventricular fibrillation occurs in approximately 5% of patients admitted for acute myocardial infarction. Although late ventricular fibrillation (> 48 hours postinfarction) may occur in stable patients, it occurs more commonly when severe left ventricular power failure is present. We have encountered late ventricular fibrillation in three of 42 (7%) patients treated with intraaortic balloon pumping (IABP) for profound cardiogenic shock secondary to myocardial infarction. These patients progressed to our hemodynamic Class A prior to weaning, and were thought to be stable prior to IABP removal. They were the only ones who expired after achieving Class A status. The episodes of late ventricular fibrillation occurred after the patients had been successfully weaned from IABP and were free of arrhythmias. This experience suggests that prolonged antiarrhythmic therapy may be indicated for postinfarction patients who have had ventricular dysrhythmias during IABP support. 相似文献
77.
Catherine E. Bach 《Oecologia》1979,44(3):319-326
Summary Experimental field plantings showed that plant diversity strongly affected the population dynamics of a specialist herbivore, the striped cucumber beetle, Acalymma vittata (Fab.) (Coleoptera: Chrysomelidae). Population densities over time were characterized by two peaks in numbers (from colonization and reproduction, respectively) and were consistently higher in cucumber monocultures (Cucumis sativus L.) than in polycultures of cucumbers, corn (Zea mays L.), and broccoli (Brassica oleracea L.). Greater abundances in monocultures appear to result from two factors: (1) per individual reproductive rates were greater in monocultures than in polycultures, and (2) mark-recapture studies confirmed that beetles stay in monocultures for a longer period of time than in polycultures. Differences in predation did not appear to contribute to the overall differences in herbivore abundances.The primary impact of A. vittata on its host plant, C. sativus, is the dissemination of bacterial wilt disease, Erwinia tracheiphila (E.F.Sm.). Greater numbers of beetles led to greater plant mortality in monocultures. It is suggested that factors other than numbers of beetles (e.g., shading, allelopathy, microclimate) are more important in influencing plant reproduction, since cucumber plants in monocultures had greater yields than did plants grown in polycultures. However, time of beetle colonization strongly affected plant parameters, indicating that the length of time during which herbivores are interacting with plants is of critical importance to plant survivorship, and thus reproduction. 相似文献
78.
79.
Dominique Weil Nguyen Van-Cong Catherine Finaz R. Rebourcet Chantal Cochet J. de Grouchy J. Frézal 《Human genetics》1977,36(2):205-211
Summary 22 independent man-hamster (HGPRT–) hybrids using male human cells with balanced reciprocal translocation t(X;2)(p22;q32) were analysed for human genes localized on chromosome 2 (IDHS, MDHS), on chromosome X (PGK, GAL, G6PD) and for the different chromosomes in relation with the balanced reciprocal translocation (chr.2, chr.2q–, chr.Xp+).The following results were obtained:The chromosomes 2 and 2q– are absent in the 22 hybrids.In 9 hybrids, the absence of MDHS in spite of the presence of the chromosome Xp+ indicates that the gene for MDHS is not localized on this chromosome (or that the gene for MDHS is not on the segment 2q32-2qter translocated on X).In 14 hybrids, the three markers of X (PGK, GAL, G6PD) and IDHS are expressed in the presence of the chromosome Xp+. This result indicates that the genes for these markers are on Xp+ or that the genes PGK, GAL, G6PD are on X without the Xp22-Xter segment, translocated on the chr.2, and that the gene for IDHS is on the 2q32-2qter segment translocated on X.In 8 hybrids, in the absence of the intact chromosome Xp+, the higher percentage of the presence of G6PD (7 hybrids) and the lower percentage of the presence of IDHS (3 hybrids) are explained by the fact that these hybrids selected in HAT medium had to retain a segment of Xp+ bearing the human gene HGPRT. G6PD appeared very close to HGPRT and IDHS very distant from HGPRT.The study of the different correlations between the presence and the absence of these four markers on Xp+ in the different hybrids indicates the following order on the chromosome Xp+ from p to q: IDHs — PGK — GAL — G6PD.
Groupe INSERM: Directeur J. Frézal
Groupe CNRS, ER, 149: Directeur J. de Grouchy 相似文献
Groupe INSERM: Directeur J. Frézal
Groupe CNRS, ER, 149: Directeur J. de Grouchy 相似文献
80.
Catherine Richard Claude Delaude Louisette Le Men-Olivier Jean Le Men 《Phytochemistry》1978,17(3):539-541
The structure of a new bisindole alkaloid has been elucidated by chemical correlation and analysis of 13C NMR spectra. 相似文献