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1.
Localization of cathepsin D in rat liver. Immunocytochemical study using post-embedding immunoenzyme and protein A-gold techniques 总被引:1,自引:0,他引:1
Light and electron microscopic localization of cathepsin D in rat liver was investigated by post-embedding immunoenzyme and protein A-gold techniques. By light microscopy, cytoplasmic granules of parenchymal cells and Kupffer cells were stained for cathepsin D. Weak staining was also noted in sinusoidal endothelial cells. In the parenchymal cells many of positive granules located around bile canaliculi. In the Kupffer cells and the endothelial cells, diffuse staining was noted in the cytoplasm in addition to granular staining. By electron microscopy, gold particles representing the antigenic sites for cathepsin D were seen in typical secondary lysosomes and some multivesicular bodies of the parenchymal cells and Kupffer cells. The lysosomes of the endothelial cells and fat-storing cells were weakly labeled. Quantitative analysis of the labeling density in the lysosomes of these three types of cells demonstrated that the lysosomes of parenchymal cells and Kupffer cells are main containers of cathepsin D in rat liver. The results suggest that cathepsin D functions in the intracellular digestive system of parenchymal cells and Kupffer cells but not so much in that of the endothelial cells. 相似文献
2.
A method for enzyme immunoassay of thyroid-stimulating hormone (TSH) is described, TSH was conjugated with horseradish peroxidase according to periodate oxidation method. Separation of the bound and free was obtained by double-antibody solid-phase technique using Sepharose 4B-anti-rabbit immunogiobulin G (IgG)-geat IgG. The fluorescence reaction using tyramine and hydrogen peroxide as substrates was used for the determination of enzyme activity in order to increase the sensitivity of enzyme immunoassay. The standard curve for serum TSH was satisfactory to recognize TSH concentrations as 0.06 μU/tube. TSH values obtained by this method correlated well with those obtained by radioimmunoassay (r, 0.96). The coefficients of variation were 1.8 to 5.3% (within assay) and 5.1 to 10.5% (between assay). The method is about equal to radioimmunoassay with respect to sensitivity. Since it requires minimal equipment and is less expensive than radioimmunoassay, it is possible to perform routine assays even in laboratories with limited facilities. 相似文献
3.
Takemi Yoshida Akio Uchida Toshinori Yamamoto Yukio Kuroiwa 《Biochimica et Biophysica Acta (BBA)/General Subjects》1981,677(2):280-286
The activities of mitochondrial type A and B monoamine oxidase were determined in the liver of rats fed a diet containing 2-acetylaminofluorene (AAF). Three days after the initiation of AAF-feeding, there was a significant decrease of type B monoamine oxidase activity without affect on type A enzyme. The decreased activity of type B monoamine oxidase, which reached a minimum after three weeks, was sustained for as long as AAF-feeding was continued. Sex-related difference in response to AAF was seen in the rat with respect to the onset and the intensity of the decreased type B monoamine oxidase activity, male rats being more sensitive to the carcinogen than female rats. In contrast to the in vivo effect, AAF showed a potent inhibitory effect on type A monoamine oxidase, rather than on type B enzyme, when added in vitro. The pI50 values were estimated to be 7.5 against type A monoamine oxidase and 4.1 against type B enzyme, respectively. The in vitro inhibition of both types of monoamine oxidase by AAF was competitive. The Ki values for AAF were calculated to be 9.51 · 10?9 M for type A monoamine oxidase and 1.30 · 10?5 M for type B enzyme, respectively. In accordance with the potent inhibitory effect of AAF on type A monoamine oxidase in vitro, a single administration of the carcinogen, at a dose of 50 mg/kg, resulted in a marked and temporal decrease of the enzyme activity in the mitochondria of male rat liver. Recovery of the decreased type B monoamine oxidase activity was slow, and the enzyme activity did not return to control levels, even if rats were fed the basal diet for 2 or 4 weeks after the cessation of AAF-feeding. 相似文献
4.
5.
Shigeo Koyasu Makoto Asada Akio Fukuda Yoshimi Okada 《Journal of molecular biology》1981,153(2):471-475
The mode of polymerization of two species of flagellins, flagellin A and flagellin B, in polar flagella of Caulobacter crescentus was examined. By immunological staining we found that 1 to 1.2 μm of the portion of the flagellar filament proximal to the cell was composed of flagellin B, whereas about 5 μm of the distal portion was composed of flagellin A. This result, together with the previous observation that a flagellin B-less mutant cannot form normal flagella but instead forms stubs in spite of their high level of flagellin A synthesis, indicates that flagellin B is very important for the formation of complete flagella and/or for the initiation of filament formation from the hook. 相似文献
6.
A simple method is described for picomole determinations of fatty acid metal salts. Fatty acid salts are directly labeled with 4-bromomethyl-7-methoxycoumarin in the presence of excess ethylenediaminetetraacetic acid tripotassium salt without any solvent extractions. The fluorescence derivatives of fatty acids are separated by reverse-phase high-performance liquid chromatography followed by fluorometric detection. The response of each fatty acid (C8-C18) calcium salt is linear from 1 to 50 micrograms/ml of samples. The detection limit is about 7 pmol. Good recoveries are obtained for the calcium salts of myrystic acid and soap (C8-C18, C18:1,2). The new method is successfully applied to the study on biodegradation of fatty acids in river water. 相似文献
7.
We investigated the effects of near-infrared irradiation on the photoconversion of Chenopodium album water-soluble chlorophyll-binding protein (CaWSCP) in the presence of sodium hydrosulfite and found a further photoconversion from CP742 to CP763, a novel form of CaWSCP. Interestingly, one-third of the absorption peak at 668 nm was recovered in CP763, but re-irradiation under oxidative conditions eliminated the photo convertibility of CaWSCP. 相似文献
8.
Keiichi Tsuji 《Bioscience, biotechnology, and biochemistry》2013,77(6):1501-1503
The peptic hydrolysis of bovine β-lactoglobulin (β-Lg) was performed to establish the basis for producing a low-phenylalanine peptide rather than a free amino acid mixture for use in the dietetics of phenylketonuria. A 1% β-Lg solution (pH 1.5) was incubated with 0.01% pepsin at 37°C for 24 hr. The peptides produced were fractionated by high-performance liquid chromatograhy to analyze their constituent amino acids. Most of the major peptides were identified in the light of the primary structure of α-Lg to assign 31 cutting points in their protein molecule. These included cutting points at the carboxyl side of Phe-82, Phe-105 and Phe-136. This result suggests that further hydrolysis of the peptic hydrolysate of β-Lg with an exopeptidase, particularly with a carboxypeptidase, would be effective in liberating phenylalanine to produce a low-phenylalanine peptide mixture. 相似文献
9.
Kenji Tsuji Shinji KitamuraHirofumi Makino 《Biochemical and biophysical research communications》2014
The kidneys are exposed to hypoxic conditions during development. Hypoxia-inducible factor (HIF), an important mediator of the response to hypoxia, is believed to have an important role in development. However, the relationship between HIF and branching morphogenesis has not been elucidated clearly. 相似文献
10.