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1.
Transplantation of various types of stem cells as a possible therapy for stroke has been tested for years, and the results are promising. Recent investigations have shown that the administration of the conditioned media obtained after stem cell cultivation can also be effective in the therapy of the central nervous system pathology (hypothesis of their paracrine action). The aim of this study was to evaluate the therapeutic effects of the conditioned medium of hiPSC-derived glial and neuronal progenitor cells in the rat middle cerebral artery occlusion model of the ischemic stroke. Secretory activity of the cultured neuronal and glial progenitor cells was evaluated by proteomic and immunosorbent-based approaches. Therapeutic effects were assessed by overall survival, neurologic deficit and infarct volume dynamics, as well as by the end-point values of the apoptosis- and inflammation-related gene expression levels, the extent of microglia/macrophage infiltration and the numbers of formed blood vessels in the affected area of the brain. As a result, 31% of the protein species discovered in glial progenitor cells-conditioned medium and 45% in neuronal progenitor cells-conditioned medium were cell type specific. The glial progenitor cell-conditioned media showed a higher content of neurotrophins (BDNF, GDNF, CNTF and NGF). We showed that intra-arterial administration of glial progenitor cells-conditioned medium promoted a faster decrease in neurological deficit compared to the control group, reduced microglia/macrophage infiltration, reduced expression of pro-apoptotic gene Bax and pro-inflammatory cytokine gene Tnf, increased expression of anti-inflammatory cytokine genes (Il4, Il10, Il13) and promoted the formation of blood vessels within the damaged area. None of these effects were exerted by the neuronal progenitor cell-conditioned media. The results indicate pronounced cytoprotective, anti-inflammatory and angiogenic properties of soluble factors secreted by glial progenitor cells.  相似文献   
2.
In many Grid infrastructures different kinds of information services are in use, which utilize different incompatible data structures and interfaces to encode and provide their data. Homogeneous monitoring of these infrastructures with the monitoring data being accessible everywhere independently of the middleware which provided it, is the basis for a consistent status reporting on the Grids’ resources and services. Thus, interoperability or interoperation between the different information services in a heterogeneous Grid infrastructure is required. Monitoring data must contain the identity of the affected Virtual Organization (VO) so that it can be related to the resources and services the VO has allocated to enable VO-specific information provision. This paper describes a distributed architecture for an interoperable information service, which combines data unification and categorization with policies for VO membership, VO resource management and data transformations. This service builds the basis for an integrated and interoperating monitoring of Grids, which provide their data to more than one VO and utilize heterogeneous information services.  相似文献   
3.
Abstract— A novel green laser source, based on a monolithic cavity microchip laser platform, has been developed. The laser is designed to be a part of a miniature and efficient RGB light source for microdisplay‐based mobile projector devices. The use of highly efficient, periodically poled MgO‐doped lithium niobate as the non‐linear frequency doubler allows for a significant increase in the overall efficiency of the green microchip laser. Specifically, a 50–150‐mW green output with a wall‐plug efficiency exceeding 10% in the temperature range of greater than 40°C has been demonstrated. A compact package for this laser source with a volume less than 0.33 cm3 is discussed and results of performance tests are presented.  相似文献   
4.
Phase transformations of an Al-12 at % Si alloy have been studied by differential barothermal analysis at temperatures of up to 700°C in argon compressed to 100 MPa. Heating at a rate of 8°C/min under a pressure of 100 MPa has been shown to increase the temperature of the L → (Al) + Si eutectic transformation in the alloy by 4°C. After crystallization of the binary eutectic, the differential thermal analysis cooling curve showed an additional exothermic peak, corresponding to the decomposition of the aluminum-based solid solution (Al) at 547°C and precipitation of silicon particles in the nanometer range. A barothermal scanning cycle reduced numerical porosity characteristics of the alloy, except for the pore number density. The lattice parameter of silicon microparticles in the alloy approaches values in the literature, whereas that of nanoparticles is slightly greater. The lattice parameter of the aluminum remains unchanged during crystallization and cooling in compressed argon. The microhardness of the aluminum matrix of the alloy corresponds to that of pure aluminum.  相似文献   
5.
It is established that semiconducting heterojunctions can be formed in the AgI-Ag2HgI4-HgI2 and CuI-Cu2HgI4-HgI2 systems obtained as a result of diffusion-controlled solid-state chemical reactions. Concentration profiles of diffusant ions in the obtained structures have been determined using the exciton spectroscopy and electron-probe microanalysis techniques. The current-voltage characteristics of heteroboundaries between ternary compounds and binary crystals have been measured in the dark and under illumination.  相似文献   
6.
Theoretical Foundations of Chemical Engineering - A technology for the demercaptanization of light hydrocarbon fractions and liquefied petroleum gas with 25% aqueous ammonia is proposed. One...  相似文献   
7.
The heat-pumping scheme based on the 1st order antiferromagnetism–ferromagnetism transition induced in FeRh alloy by one-dimensional tensile stress is proposed. Using the model S–T diagram for this alloy, the heat-pump cycles are drawn up based both on the transition latent heat absorption and emission when the transition is induced isothermally and on the change in alloy's temperature when the transition is induced adiabatically by applying tensile stress. The calculated values of heat coefficient φ for the cycles are 30 at ΔT=5 К and 20 at ΔT=10 К, where ΔT is the difference between the temperature surrounding and that of the heat receiver. These values are achieved using the tensile stress of 1·109 Pa. The high values of φ make it possible to consider Fe–Rh alloys near the equiatomic composition as an effective refrigerant for elastocaloric heat-pumping near the room temperature.  相似文献   
8.
The results of an investigation of the interaction of zirconium dioxide refractories – ceramic and concrete with iron oxides – are presented. The investigations showed that starting at 1600 K in an argon atmosphere contact of a mixture of iron oxides with refractories gives rise to erosion of the latter. Under isothermal conditions (2270 K), ceramic with 16% porosity completely absorbs a melt with mass 1/7 of the ceramic mass. The concrete confines the same melt mass with a lower temperature 1870 K and, in the process, unlike the ceramic, it loses strength.The results obtained and the published data were used to analyze the operation of a refractory protective layer of an EPR trap.  相似文献   
9.
The introduction of anionic surface active substances into butadiene-styrene rubbers doubles or trebles the work of delamination (A) for fabric-rubber bonds. The increase of A is due to a rise in mechanical loss through a higher rate of relaxation of a polymer adsorbed by a filler (τH). A linear dependence between A and logτH is found.  相似文献   
10.
The presence of metastable cubic modifications has been revealed by X-ray diffraction in polycrystalline CdS and CdSe powders with grain sizes on the order of several dozen nanometers. The optical reflection and photoluminescence spectra of the cubic CdS phase have been measured in the temperature interval of 77–295 K. The main exciton transition energies and the temperature coefficients of the bandgap width variation have been determined.  相似文献   
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