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41.
Konstantin V. Dergilev Evgeny K. Shevchenko Zoya I. Tsokolaeva Irina B. Beloglazova Ekaterina S. Zubkova Maria A. Boldyreva Mikhail Yu. Menshikov Elizaveta I. Ratner Dmitry Penkov Yelena V. Parfyonova 《International journal of molecular sciences》2020,21(24)
Cell therapy of the post-infarcted myocardium is still far from clinical use. Poor survival of transplanted cells, insufficient regeneration, and replacement of the damaged tissue limit the potential of currently available cell-based techniques. In this study, we generated a multilayered construct from adipose-derived mesenchymal stromal cells (MSCs) modified to secrete stem cell factor, SCF. In a rat model of myocardium infarction, we show that transplantation of SCF producing cell sheet induced activation of the epicardium and promoted the accumulation of c-kit positive cells in ischemic muscle. Morphometry showed the reduction of infarct size (16%) and a left ventricle expansion index (0.12) in the treatment group compared to controls (24–28%; 0.17–0.32). The ratio of viable myocardium was more than 1.5-fold higher, reaching 49% compared to the control (28%) or unmodified cell sheet group (30%). Finally, by day 30 after myocardium infarction, SCF-producing cell sheet transplantation increased left ventricle ejection fraction from 37% in the control sham-operated group to 53%. Our results suggest that, combining the genetic modification of MSCs and their assembly into a multilayered construct, we can provide prolonged pleiotropic effects to the damaged heart, induce endogenous regenerative processes, and improve cardiac function. 相似文献
42.
Galina V. Beznoussenko Hee-Seok Kweon Irina S. Sesorova Alexander A. Mironov 《International journal of molecular sciences》2022,23(7)
The Golgi complex is the central station of the secretory pathway. Knowledge about the mechanisms of intra-Golgi transport is inconsistent. Here, we compared the explanatory power of the cisterna maturation-progression model and the kiss-and-run model. During intra-Golgi transport, conventional cargoes undergo concentration and form cisternal distensions or distinct membrane domains that contain only one membrane cargo. These domains and distension are separated from the rest of the Golgi cisternae by rows of pores. After the arrival of any membrane cargo or a large cargo aggregate at the Golgi complex, the cis-Golgi SNAREs become enriched within the membrane of cargo-containing domains and then replaced by the trans-Golgi SNAREs. During the passage of these domains, the number of cisternal pores decreases. Restoration of the cisternal pores is COPI-dependent. Our observations are more in line with the kiss-and-run model. 相似文献
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Astakhova IK Samokhina E Babu BR Wengel J 《Chembiochem : a European journal of chemical biology》2012,13(10):1509-1519
We describe fluorescent oligonucleotide probes labeled with novel (phenylethynyl)pyrene dyes attached to locked nucleic acids. Furthermore, we prove the utility of these probes for the effective detection of single-nucleotide polymorphisms in natural nucleic acids. High-affinity hybridization of the probes and excellent fluorescence responses to single-base mismatches in DNA/RNA targets are demonstrated in model dual-probe and doubly labeled probe formats. This stimulated us to develop two diagnostic systems for the homogeneous detection of a drug-resistance-causing mutation in HIV-1 protease cDNA and RNA gene fragments. Target sequences were obtained by analysis of 200 clinical samples from patients currently receiving anti-HIV/AIDS combination therapy at the Russian Federal AIDS Center. Using these fluorescent oligonucleotides, we were able to detect the target mutation despite all the challenges of the natural targets, that is, the presence of additional mutations, neighboring sequence variation, and low target concentration, which typically reduce binding and effectiveness of sensing by fluorescent oligonucleotides. 相似文献
46.
Vladimir Yakushin Maria Misane Oskars Bikovens Dzintra Vilsone Irina Sevastyanova 《Journal of Coatings Technology and Research》2016,13(2):317-324
Tall oil fatty acids (TOFA) were esterified with trimethylolpropane (TMP) without a catalyst at different molar ratios of TMP to TOFA. A molar ratio was defined, at which a polyol stable in long-term storage, with the maximum content of TMP monoesters, was synthesized. Fourier transform infrared spectroscopy and gas chromatography were used for the identification of the polyols’ chemical structure and composition. Based on the synthesized polyols, polyurethane coatings were prepared. The effect of the isocyanate index and concentration of traditional Sn-based and less toxic Bi-based catalysts on the gel time of the polyurethane composition, and the mechanical and thermal properties of the coatings was studied. It was found that the new coatings had high tensile strength and modulus of elasticity, comparable with the strength and modulus of the polyurethane based on diethanolamides of TOFA. The initial temperature of decomposition of these coatings was higher than that of the polyurethanes based on esters of TOFA and a number of uralkyds. The coatings based on TMP esters of TOFA were obtained without the use of solvents, and potentially, these esters can be used in spray-applied VOC-free polyurethane coatings’ formulation. 相似文献
47.
Relevance of the acid–base approach in prediction of adhesion properties in two‐component injection moulding 下载免费PDF全文
Eduard Kraus Sonja Horvat Christian Deubel Christian Staudigel Benjamin Baudrit Peter Heidemeyer Martin Bastian Irina Starostina Oleg Stoyanov 《应用聚合物科学杂志》2016,133(8)
We demonstrate the use of innovative wetting method in prediction of the adhesion properties of biobased polymers for two‐component injection moulding, taking into account the acid–base surface properties of joined materials. The measurements were carried out in accordance with modified Berger method by calculation of the difference in shortened acidity parameter ΔDshort between hard and soft component. Correlation factors up to 0.99 were observed between ΔDshort and peel force. In comparison to results obtained by conventional wetting methods, high potential for the selection of components with high interface adhesion and for prediction of the functionality by the acid–base approach was demonstrated. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43048. 相似文献
48.
Gerasimov Sergey I. Ilyushin Mikhail A. Putis Sergey M. Dushenok Sergey A. Shugalei Irina V. Sudarikov Andrey M. 《含能材料》2022,30(4):370-378
In the present work it is found that the pyrotechnic composition VS-2 can be initiated with flash lamps IFC-500 and EVIS. VS-2 pyrotechnic composition contains 90% of mercury(Ⅱ) 5-hydrazinotetrazolate perchlorate and 10% of optically transparent copolymer of 2-methyl-5-vinyltetrazole and methacrylic acid (PVMT). We have found that the flash lamps make it possible to initiate combustion of VS-2 composition with its transition to detonation both in cylindrical charges placed in brass caps of 5 mm diameter and 2 mm high, and film charges with 10 mm×80 mm in size and surface weights of 60 mg·cm-2 and 90 mg·cm-2, showing ignition delay times 10 μs and 3 μs, respectively. We also measured detonation velocities for VS-2 composition film charges, which were 4375-4505 m·s-1 (of the charge being surface mass 60 mg·cm-2) and 4221-4281 m·s-1 (of the charge being surface mass 90 mg·cm-2) and their blasting action on the aluminum plate. The depths of the normal shock wave imprints at the charge-barrier interface were 0.6-0.7 mm (for surface mass of the film charges 60 mg·cm-2) and 1.2-1.3 mm (for surface mass of the film charges 90 mg·cm-2). 相似文献
49.
Nevzglyadova OV Kuznetsova IM Mikhailova EV Artamonova TO Artemov AV Mittenberg AG Kostyleva EI Turoverov KK Khodorkovskii MA Soidla TR 《Yeast (Chichester, England)》2011,28(7):505-526
The intensity of amyloid-bound thioflavine T fluorescence was studied in crude lysates of yeast strains carrying mutations in the ADE1 or ADE2 genes and accumulating the red pigment (a result of polymerization of aminoimidazoleribotide), and in white isogenic strains--either adenine prototrophs or carrying mutations at the first stages of purine biosynthesis. We found that the red pigment leads to a drop of amyloid content. This result, along with the data on separation of protein polymers of white and red strains in PAGE, suggests that the red pigment inhibits amyloid fibril formation. The differences in transmission of the thioflavine T fluorescence pattern by cytoduction and in blot-hybridization of pellet proteins of red and white [PSI(+) ] strains with Sup35p antibodies confirmed this conclusion. Purified red pigment treatment also led to a decrease of fluorescence intensity of thioflavine T bound to insulin fibrils and to yeast pellet protein aggregates from [PSI(+) ] strains. This suggests red pigment interaction with amyloid fibrils. Comparison of pellet proteins from red and white isogenic strains separated by 2D-electrophoresis followed by MALDI analysis has allowed us to identify 48 pigment-dependent proteins. These proteins mostly belong to functional classes of chaperones and proteins involved in glucose metabolism, closely corresponding to prion-dependent proteins that we characterized previously. Also present were some proteins involved in stress response and proteolysis. We suppose that the red pigment acts by blocking certain sites on amyloid fibrils that, in some cases, can lead in vivo to interfere with their contacts with chaperones and the generation of prion seeds. 相似文献
50.
Masakazu Umezawa Atsuto Onoda Irina Korshunova Alexander C. Ø. Jensen Ismo K. Koponen Keld A. Jensen Konstantin Khodosevich Ulla Vogel Karin S. Hougaard 《Particle and fibre toxicology》2018,15(1):36