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The functional state of myocardial mitochondria, the glycogen and nucleic acid contents in myocardium, and morphometry of structural elements of cardiomyocytes and myocardial capillary network were investigated in order to select the optimal regimen of decimeter wave exposures with power density of 10, 120 and 240 mW/cm2 on the area of thyroid gland. It was shown that the thyroid gland exposure to decimeter waves at these intensities resulted in functional shifts in energy and plastic processes in myocardium and capillary blood supply. These changes increased to a considerable extent as the intensity of exposure was increasing and reached the maximum at power density of 240 mW/cm2 but event at this intensity there was not found the injurious effect of decimeter waves on the myocardium.  相似文献   
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Resident cardiac stem cells, known as “cardiogenic progenitor cells” (CPCs), are a heterogeneous population of immature cells residing in the myocardium and capable of self-renewal and differentiation into cardiomyocyte-like and vascular-like cells. CPCs are usually isolated by long enzymatic digestion of heart tissue and selection with stem cell markers. However, long exposure to enzymatic digestion and the small size of a myocardial sample significantly hinder acquiring a large number of viable cells. To avoid these problems, we developed a method based on CPC growth ex vivo and subsequent immunomagnetic selection.  相似文献   
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Two novel assay systems for the determination of sialyltransferase activity using a tetramethylrhodamine-labeled disaccharide Galbeta1-4GlcNAc (2) as the acceptor are described. The TMR-labeled disaccharide 2 was synthesized by directly coupling Galbeta1-4GlcNAc-O-(CH(2))(6)NH(2) (1) with 5-tetramethylrhodamine N-hydroxysuccinimide ester. The K(m) value for compound 2 obtained with alpha-2,6-sialyltransferase from rat liver (EC 2.4.99.1) was 160 +/- 20 microM. After incubation of compound 2 with sialyltransferase the product and the unreacted acceptor substrate were separated either by thin-layer chromatography (TLC) on C-18 silica gel plates or by polyacrylamide gel electrophoresis (PAGE). The density of the spots on the TLC plates and the fluorescence of the bands on the gel were quantified. The assay conditions were optimized using crude bovine colostrum extract and also alpha-2, 6-sialyltransferase from rat liver. The detection limits for the TLC and PAGE assays were 1 and 0.4 microU of the rat liver enzyme, respectively. Either assay allows the parallel investigation of several samples at a time and is useful for the testing of fractions during enzyme purification.  相似文献   
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Reactive oxygen species (ROS) play a role in male infertility, where excessive amounts impair spermatozoal motility. Epididymal antioxidant enzymes protect spermatozoa from oxidative damage in the epididymal lumen. Antioxidant secretions from the seminal vesicle protect spermatozoa after ejaculation. As it is known that with age there is increased generation of ROS, the goals of this study were to determine how aging affects the response of antioxidant enzymes in the epididymis, seminal vesicles, and liver to l-buthionine-S,R-sulfoximine (BSO) mediated glutathione (GSH) depletion, and to examine the impact of GSH depletion on motility parameters of spermatozoa from the cauda epididymidis in young (4-mo-old) and old (21-mo-old) rats. Levels of GSH and glutathione disulfide (GSSG), as well as activities of glutathione peroxidase, glutathione reductase, catalase, and superoxide dismutase, were measured in the caput, corpus and cauda epididymidis, seminal vesicles, and liver. Spermatozoal motility was assessed by computer-assisted sperm analysis. Significant age-related changes in antioxidant enzyme activities were found in the liver and cauda epididymidis. Glutathione depletion clearly affected tissues in both young and old. The compounding effect of age was most evident in the cauda epididymidis, seminal vesicles, and liver, where antioxidant enzyme activities changed significantly. Additionally, spermatozoa motility was adversely affected after BSO treatment in both age groups, but significantly more so in older animals. In summary, the male reproductive tissues and liver undergo age-related changes in antioxidant enzyme activities and in their response to GSH depletion.  相似文献   
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Cell sheets (CS) from c-kit+ cardiac stem cell (CSC) hold a potential for application in regenerative medicine. However, manufacture of CS may require thermoresponsive dishes, which increases cost and puts one in dependence on specific materials. Alternative approaches were established recently and we conducted a short study to compare approaches for detachment of CS from c-kit+ CSC. Our in-house developed method using chelation by Versene solution was compared to UpCell? thermoresponsive plates in terms of CSC proliferation, viability, gap junction formation and engraftment in a model of myocardial infarction. Use of Versene solution instead of thermoresponsive dishes resulted in comparable CS thickness (approximately 100 mcm), cell proliferation rate and no signs of apoptosis detected in both types of constructs. However, we observed a minor reduction of gap junction count in Versene-treated CS. At day 30 after delivery to infarcted myocardium both types of CS retained at the site of transplantation and contained comparable amounts of proliferating cells indicating engraftment. Thus, we may conclude that detachment of CS from c-kit+ CSC using Versene solution followed by mechanical treatment is an alternative to thermoresponsive plates allowing use of routinely available materials to generate constructs for cardiac repair.  相似文献   
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