The use of endovascular thrombectomy among the patients with acute ischemic stroke caused by the occlusion of large cerebral vessels

The effectiveness and complications of endovascular thrombectomy were analyzed. The obtained results show the reduction in mortality and disability among the patients after endovascular treatmen

Effect of extracts from microalgae on cytokine levels in female C57Bl6 mice

Microalgae from the freshwater basins and seas are a valuable source of broad-spectrum biologically active substances that can affect the cells of immune system and their functional state. Cytokines are involved in all vital processes proceeding in the living cells (proliferation, maturation, differentiation, apoptosis/ necrosis). A study was performed in order to assess the effects of standard food formula for experimental animals supplemented with oil extract of microalgae from various systematic groups upon the levels of cytokines in blood serum, culture media conditioned by immunocytes, as well as kidney and liver tissues. The standard food was impregnated in oil extracts of microalgae (C. vulgaris, Coelastrella sp., A. platensis, C. closterium, and P. purpureum). In control series, the food was impregnated with pure vegetable oil. The animals were fed these foods for 12 days. Blood, spleen and thymus were taken to isolate immunocytes, kidneys and liver, and dimethyl sulfoxide extracts of the cells were produced. The conditioned media of splenocytes and thymocytes were obtained by adding concanavalin A (0 and 10 μg/ml) to the cultured cells. The levels of NO, IL-1β, IL-10, TNFα, and NO were determined in serum, conditioned media, and tissue extracts. In serum, the influence of microalgae on the levels of IL-1β and TNFα was revealed. Activation of immunocytes in experimental groups was followed by changes in IL-1β, TNFα and IL-10 production. Changes of cytokine and NO levels were revealed in liver and kidney extracts in experimental groups. Thus, microalgae extracts of various systematic groups affect the levels of cytokines in blood serum, cultural media conditioned by splenocytes and thymocytes, kidney and liver tissues

Heat Capacity of PbS: Isotope Effects

In recent years, the availability of highly pure stable isotopes has made possible the investigation of the dependence of the physical properties of crystals, in particular semiconductors, on their isotopic composition. Following the investigation of the specific heat ($C_p$, $C_v$) of monatomic crystals such as diamond, silicon, and germanium, similar investigations have been undertaken for the tetrahedral diatomic systems ZnO and GaN (wurtzite structure), for which the effect of the mass of the cation differs from that of the anion. In this article we present measurements for a semiconductor with rock salt structure, namely lead sulfide. Because of the large difference in the atomic mass of both constituents ($M_{\rm Pb}$= 207.21 and ($M_{\rm S}$=32.06 a.m.u., for the natural isotopic abundance) the effects of varying the cation and that of the anion mass are very different for this canonical semiconductor. We compare the measured temperature dependence of $C_p \approx C_v$, and the corresponding derivatives with respect to ($M_{\rm Pb}$ and $M_{\rm S}$), with \textit{\textit{ab initio}} calculations based on the lattice dynamics obtained from the local density approximation (LDA) electronic band structure. Quantitative deviations between theory and experiment are attributed to the absence of spin-orbit interaction in the ABINIT program used for the electronic band structure calculations.Comment: 17 pages including 10 Fig

EFFECT OF ERYTHROPOIETIN ON CYTOKINE PRODUCTION BY STEM CELLS

Erythropoietin (EPO) is mainly used to stimulate erythropoiesis. Its cytoprotective effects upon other cells of the human body and animals were recently shown, in particular, anti-apoptotic effect was observed. EPO effect upon the cells is mediated by interaction with erythropoietin receptor, with a complex forming a heterodimeric bond with β-common chain (CD131). In the present work, we studied the changes in erythropoietin receptor expression, and production spectrum of biologically active molecules in bone marrow mononuclear cells (BM-MNC) of patients with coronary heart disease. The flow cytometric assays showed that short-term incubation of BM-MNC with erythropoietin caused increased expression of the erythropoietin receptors on hematopoietic stem cells and tended to reduce the number of endothelial progenitor cells carrying the erythropoietin receptors. Solid-phase enzyme immunoassay in conditioned media from BM-MNC revealed that long-term (72 hours) exposure of BM-MNC to erythropoietin promoted increased production of IL-1β, PDGF-AB, and Epo, if compared to the basal production level (p < 0.05). Short-term incubation of BM-MNC with erythropoietin (60 minutes) caused a significant increase in the IL-1β, PDGF-AB and CXCL-12 / SDF-1α production levels, as well as significant reduction in the IL-10 production levels compared to the basal levels (p < 0.05)

Effect of erythropoietin on bone marrow mononuclear cells

Stem/progenitor cells are considered an alternative method of heart failure therapy by promoting regeneration of damaged myocardium in myocardial infarction. Effectiveness of cell therapy depends on the population composition and functional activity of the cell graft, and, in turn, it depends on the conditions of microenvironment. Cultivation of stem/progenitor cells with erythropoietin stimulates proliferative potential causing in vitro resistance to hypoxia, and in vivo stimulation of angiogenesis. We aimed for assessing effects of erythropoietin upon hematopoietic cells. We studied some effects of short-term incubation of bone marrow mononuclear cells (BM-MNCs) in patients with coronary heart disease (CHD) with erythropoietin upon cellular phenotype, cell cycle, apoptosis and their proliferative potential. BM-MNCs were isolated from bone marrow aspirate from patients with CHD in a density gradient, then incubated for 60 minutes with erythropoietin (33.4 IU/ml). Using flow cytometric assay of the total BM-MNCs pool, we have shown there endothelial progenitor cells at different stages of maturation and differentiation, mesenchymal stem cells are. Their total number did not exceed 30%. Short-term incubation of BM-MNCs with erythropoietin reduces expression of CD184 “homing receptor” molecules on CD34+ cells, and causes increase of CD184 on CD31+ cells in the BM-MNCs pool (p < 0.05). In addition, erythropoietin has been shown to cause a delay of CD34+ cells in the resting phase (G0G1), reduce a proportion of cells in the synthetic phase (S) and mitosis (G2/M) (p<0.05), and does not affect apoptosis, as shown by Annexin V-FITC Apoptosis Detection Kit. Erythropoietin had no significant effects on expression on BM-MNCs surface molecules involved in providing adhesion, such as CD18, CD29, CD44, CD49a, CD54, CD62E, CD146, and CD202b. MTT-method has shown that the short-term preincubation of BM-MNCs with erythropoietin contributed to a significant decrease in proliferative activity of BM-MNCs (p < 0.05). However, there was a tendency towards increased resistance of erythropoietin-pretreated BM-MNCs to oxidative stress induced by hydrogen peroxide. We have also revealed a correlation between the numbers of endothelial progenitor cells at different stages of differentiation, and numbers of hematopoietic stem cells in the total BM-MNCs pool. The number of CD34+/CD133+, CD34- / CD31+, CD45+/EpoR+, and CD34+/EpoR+ in BM-MNCs pool are dependent on the age of patients. Hence, a short-term incubation of BM-MNCs with erythropoietin promotes the cells to be retained in resting phase of the cell cycle, thus, in turn, helping to reduce proliferative potential of BM-MNCs

CORRELATION BETWEEN CYTOKINE CONTENT IN LYMPH OF THORACIC LYMPH DUCT AND MESENTERIC LYMPH NODE STRUCTURAL TRANSFORMATIONS IN EXPERIMENTAL MAMMARY TUMOR AND CHEMOTHERAPY

The aim of the study was to fulfill correlation analysis of morphometry of the mesenteric lymph nodes and the concentration of cytokines in the lymph of the thoracic duct in breast cancer induced by intramammary administration of N-methyl-N-nitrosourea, chemotherapy according to the CMF scheme (cyclophosphamide, methotrexate, 5-fluorouracil). The results of the study. At breast cancer revealed positive correlation: in the germinative centers and medullary cords of cytokine IL-5 with mitotically dividing cells, chemokines MIP-1α with average lymphocytes, in the germinative centers of immunoblasts with cytokine GRO/KC, in the paracortical zone chemokine MCP-1 with macrophages, reticular cells with IL-6 and M-CSF, in the medullary sinuses chemokine GRO/KC with small lymphocytes and mature plasma cells (number which decreases). All this may indicate the activity of the local immune response in the lymph nodes aimed on the antitumor protection. After chemotherapy of breast cancer, compared with breast cancer without treatment, revealed positive relationship, which may indicate increased immunomodulatory and antitumor actions of cytokines: correlation of interferon IFNγ with small lymphocytes (number which increased) and macrophages in the germinative centers and mitotically dividing cells in the medullary cords, correlation in the germinative centers of immunoblasts with MIP-1α and increased of number small lymphocytes in T-dependent zone lymph nodes, correlation in medullary cords of interleukin IL-17 with mature plasma cells (number which increased) , correlation of interleukin IL-18 with mature plasma cells in medullary sinuses. Conclusion. Study of the correlation of the concentration of cytokines in the lymph of the thoracic duct with structural changes in the mesenteric lymph nodes revealed dependencies aimed at increasing the immunomodulating and antitumor effects of cytokines

STRUCTURAL TRANSFORMATIONS IN AXILLARY AND MESENTERIC LYMPH NODES IN CHEMOTHERAPY AND SURGICAL TREATMENT OF EXPERIMENTAL MAMMARY TUMOR

Was conducted histological study axillary and mesenteric lymph nodes in breast cancer induced by intramammary administration of N-methyl-N-nitrosourea, chemotherapy according to the CMF scheme (cyclophosphamide, methotrexate, 5-fluorouracil), operative removal of breast tumors (6.5 months from the beginning of the experiment). The results of the study. At chemotherapy of breast cancer, compared with the group with breast cancer without treatment, there was a decrease in the number of tumor cells in the axillary lymph nodes in comparison with mesenteric lymph nodes. The decrease in the area of the paracortical zone and the area of secondary lymphoid nodes remain in the axillary lymph nodes, in comparison with breast cancer without treatment. The reduction of the paracortical zone square remains in mesenteric lymph nodes. The area of lymphoid nodules with germinative centers decreases. The number of postcapillary venules with high endothelium and the number of macrophages in structural zones grow down. In the axillary lymph nodes after surgical treatment of breast cancer and chemotherapy in comparison with the treatment of breast cancer only with cytostatics, there is decrease in the area of the paracortical zone (with an increase in the number of small lymphocytes) and medullare cords. The area of lymphoid nodules with germinative and without germinative centers increases. In mesenteric lymph nodes, drainage function is reduced, increased the area of the paracortical zone, reduced the areas of lymphoid nodules with germinative centers and medullare cords (increased proliferative activity of cells), macrophage reaction in the cortical substance was revealed. Conclusion. The severity of structural transformations in cytoarchitectonics of the axillary and mesenteric lymph nodes depends on the treatment method

Dynamical Phases of Driven Vortices Interacting with Periodic Pinning

The finite temperature dynamical phases of vortices in films driven by a uniform force and interacting with the periodic pinning potential of a square lattice of columnar defects are investigated by Langevin dynamics simulations of a London model. Vortices driven along the [0,1] direction and at densities for which there are more vortices than columnar defects ($B>B_{\phi}$) are considered. At low temperatures, two new dynamical phases, elastic flow and plastic flow, and a sharp transition between them are identified and characterized according to the behavior of the vortex spatial order, velocity distribution and frequency-dependent velocity correlationComment: 4 pages with 4 figures. To be published in Phys. Rev. B Rapid Communication

Optimization of laser stabilization via self-injection locking to a whispering-gallery-mode microresonator: experimental study

Self-injection locking of a diode laser to a high-quality-factor microresonator is widely used for frequency stabilization and linewidth narrowing. We constructed several microresonator-based laser sources with measured instantaneous linewidths of 1 Hz and used them for investigation and implementation of the self-injection locking effect. We studied analytically and experimentally the dependence of the stabilization coefficient on tunable parameters such as locking phase and coupling rate. It was shown that precise control of the locking phase allows fine tuning of the generated frequency from the stabilized laser diode. We also showed that it is possible for such laser sources to realize fast continuous and linear frequency modulation by injection current tuning inside the self-injection locking regime. We conceptually demonstrate coherent frequency-modulated continuous wave LIDAR over a distance of 10 km using such a microresonator-stabilized laser diode in the frequency-chirping regime and measure velocities as low as sub-micrometer per second in the unmodulated case. These results could be of interest for cutting-edge technology applications such as space debris monitoring and long-range object classification, high resolution spectroscopy and others