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V S Repin

Publications and source records attributed to V S Repin.

At least 163 records · Page 9Linked to original sources

[Quantitative study of endothelial defects in the aorta and carotid artery in experimental atherosclerosis].

The inner surface of the aorta and carotid artery in normal rabbits (group 1) and after 3 weeks (group 2), 6 weeks (group 3) and 8 months (group 4) of hypercholesterolemia was studied by scanning electron microscopy. In all the cases the area of de-endothelialized zones was equally small. Incidence of microdefects in the endothelium (argyrophilic cells, craters and stomata) increased in group 2, but decreased in group 3 and group 4 (outside the plaques). No typical endothelium with argyrophilic borders was observed on 39.2% of the plaque surface in group 4, though the cells were present. The data obtained show that vast zones of de-endothelialization do not precede the development of atherosclerotic plaques.

Animals↗

[Micro-quantitative determination of alpha1-antitrypsin by unidimensional capillary counter-immunodiffusion].

The immunoprecipitation reaction for the determination of microamounts of alpha1-antitrypsin was conducted in the capillaries filled with a microvolume of a 1% agarose gel (the gel length was 7--8 mm, and the diameter--0.6 mm). Microamounts of the antigen and antiserum were applied to the surface of the opposite ends of the gel. Precision control of these manipulations was carried out by means of an ocular micrometer of a binocular lens. The amount of the formed immunoprecipitate in gel was calculated by the summated optic density after staining with amido black recorded by the method of double-wave microspectrophotometry. Sensitivity of the method was 0.3--1.0 ng of alpha1-antitrypsin. The linear plot between the amount of alpha1-antitrypsin and the amount of the precipitate formed was found within the range of 1--25 ng of protein. The error was about 10%.

Immunodiffusion↗

[Neurospecific protein S-100 in the synaptosomes of rat cerebral cortex].

Neurospecific S-100 protein was revealed by the methods of microelectrophoresis in the 15% polyacrylamide gel with a 0.1% sodium dodecylsulfate and by a highly purified S-100 protein "marker" in the composition of low molecular acidic proteins of the rat brain synaptosomes. The S-100 protein conten constitutes about 15-2o% of the low molecular acidic synaptosomal porteins in the rat brain.

Animals↗

[Detection of alpha 1-antitrypsin in unfertilized ova of albino rats].

500--700 rat oocytes were solubilized in 0.3--0.6 ml of 1% sodium dodecyl sulphate (SDS) --0.06 tris-HCl, pH 6.7. The excess of SDS was removed in the form of unsoluble Ba2 (SDS) and the lysate was placed on the surface of 1% agarose microgel, performed in a glass capillar with the inner diameter 600 and the length of gel 7--8 nm. The microvolume (1.3 mcl) of monospecific antiserum against alpha1-human antitrypsin was placed on the opposite surface of the agarose gel. After 48 hours, the amount of microimmunoprecipitate was determined by staining the gel with Amido Black 10 B, followed by quantitative scanning using a double wave microspectrophotometer. The mean value of alpha1-antitrypsin was about 2.3+/-1.4 pcg per ovum. It is supposed that this antienzyme may terminate the "zone" and "cortical" reactions during the fertilization in mammals.

Animals↗

[A study of the protein composition of the zona pellucida of mammalian oocytes and zygotes by a method of microelectrophoresis in polyacrylamide gel].

Z. pellucide from oocytes and zygotes of CBA mice and albino rats were lysed in a microvolume of 1% buffered sodium dodecylsulphate (SDS). The microlysate (about 1,0--2,0-10(-7) g protein) was fractionated by means microdiscelectrophoretic technique, using 10%- and 15%-polyacrylamide gel containing 0.1% SDS. The new proteins with increased anodic mobility was found among zonal proteins after fertilization in CBA mice and rats. Homogenous fraction of glycoprotein (approximately molecular weight 44 000) is found in z. pellucida of rat oocytes. This glycoprotein fraction from rat zygote coats produces 3 components moving to anode under electrophoresis. The data obtained support the hypothesis that the mechanism of "zonal fraction" under fertilization in mammals can be due to partial lysis of coat proteins by proteinase of cortical granules.

Animals↗

[Molecular weight characteristics of the proteins of oocytes and of cleavage ova in CBA mice by means of capillary microdisc electrophoresis].

5-20 oocytes or cleaving embryos of CBA mice were dissolves in 0.2-0.5 ml of 1% buffered sodium dodecylsulfate (SDS), and soluble proteins were separated using electrophoresis in capillaries filled with PAA-SDS-gel. The method enabled us to calculate the approximate molecular weight of proteins by relative mobilities and allowed to determine 1-5 mmcg protein in a single band. 7 groups of proteins were identified in mouse oocytes using 10% PAA-0.1% SDS-gel with the following molecular weights: 208 000, 206 000, 155 000, 112 000, 59 000, 40 000 and 30 000, resp. The same groups of protein were discovered in zygotes and cleaving mouse embryos. The molecular weight distribution of low-molecular weight basic proteins of CBA mice is species-specific and reveals a qualitative changes in the early embryogenesis.

Animals↗

[Constitutive proteins of the oocytes and early embryos of rats].

5 protein fractions were identified and their relative mobility was determined in the rat oocytes and cleaving embryos by means of vertical capillary microdisc-electrophoresis in 7.5% polyacrilamide gel (PAA-gel). The same fractions were identified in the cleaving embryos devoid of zona pellucida. A conclusion was drawn that these proteins were present in the oocyte cytoplasm and kept in the cleaving embryos until the stage of implantation. 4 groups of proteins with different anodic mobility were identified in the isolated zona pellucida by means of microdisc-electrophoresis in 7.5% PAA-gel added with 1% sodium dodecylsulfate (SDS). The molecular weight of low molecular weight proteins of oocytes and preimplantation embryos was determined by means of disc-electrophoresis in 14% PAA-gel with 1% SDS. The zona pellucida of one embryo contained, according to the data of capillary spectrophotometry, 5 ng of protein.

Animals↗

[Determination of protein concentration in cleaving mammalian ova by the capillary spectrophotometry method].

A micromodification of the Lowry's method is described which allows to measure reliably the protein content in 5-20 embryos of white rats and CBA mice. Differences in the protein content in rat embryos at the stages of 2 blastomeres and blastocyst were shown to be statistically unreliable (20.2 +/- 1.4 and 18.9 +/- 1.3 ng, resp.). The protein content in the mouse embryos at the same two stages differs reliably (19.1 +/- 1.1 and 22.0 +/- +/- 1.7 ng, resp.). The protein content in zona pellucida does not differ reliably from those in rat embryos both at the stages of 2 blastomeres (4.5 ng) and blastocyst (2.3 ng). The protein content in embryos devoid of zona pellucida decreased after 3 hours incubation in the medium 199 at 37 degrees at the stages of morula and blastocyst by 17-20% in rats and by 50% in mice. Addition of 1% serum albumin to the incubation medium did not prevent the partial "loss" of protein by the embryos. The protein content in the rat and mouse embryos at the stage of 2 blastomeres suffered no changes under long-term incubation in the medium 199.

Animals↗