24 research outputs found

    Experimental Model of Pancreonecrosis Induced by Auto-bile Injection

    Get PDF
    AIM: The aim of the study is to create an easily reproducible experimental model of pancreonecrosis with the least aggressive technique of the operation. METHODS: Twenty-two outbred rabbits of comparable weight and age were included in the study. The animals were removed from the experiment 12, 24, and 48 h after the injection of auto-bile into the parenchyma of the pancreas. RESULTS: After completion of the experiment, rabbit pancreas was extracted, macroscopic and microscopic description was given. CONCLUSION: According to the results of the study, the proposed model is considered as consistent for reproducing pancreonecrosis in an experiment with less aggressive surgical technique

    Hemilability of phosphine-thioether ligands coordinated to trinuclear Mo3S4 cluster and its effect on hydrogenation catalysis

    Get PDF
    Ligand-exchange reactions of [Mo3S4(tu)8(H2O)]Cl44H2O (tu = thiourea) with (PhCH2CH2)2PCH2CH2SR ligands, where R = Ph (PS1), pentyl (PS2) or Pr (PS3) afford new complexes isolated as [Mo3S4Cl3(PS1)3]PF6 ([1]PF6), [Mo3S4Cl3(PS2)3]PF6 ([2]PF6) and [Mo3S4Cl3(PS3)3]PF6 ([3]PF6) salts in 30-50% yields as the major reaction products. The crystal structures of [1]PF6 and [2]PF6 were determined by X-ray diffraction (XRD) analysis. Each of the three phosphine-thioether ligands is coordinated in a bidentate chelating mode to a different molybdenum atom of the Mo3S4 trinuclear cluster, herewith all the phosphorus atoms of the phosphino-thioether ligand are located trans to the capping sulfur (3-S). A second product that forms in the reaction of [Mo3S4(tu)8(H2O)]Cl44H2O with PS1 corresponds to the neutral [Mo3S4Cl4(PS1)2(PS1*)] complex. Its XRD analysis reveals both bidentate (PS1) and monodentate (PS1*) coordinating modes of the same ligand. In the latter mode the phosphinethioether is coordinated to a Mo atom only via the P atom. All compounds were characterized by 1H, 31P{1H} NMR, electrospray-ionization (ESI) mass spectrometry and cyclic voltammetry (CV). Reactions of [1]PF6, [2]PF6 and [3]PF6 with an excess of Bu4NCl in CD2Cl2 were followed by 31P{1H} NMR. The spectra indicate equilibrium between cationic [Mo3S4Cl3(PSn)3] + and neutral [Mo3S4Cl4(PSn)2(PSn*)] (n = 1, 2) species. The equilibrium constants were determined as 2.5 ± 0.2103 , 43 ± 2 М -1 and 30 ± 2 М -1 (at 25°C) for [1]PF6, [2]PF6 and [3]PF6, indicating quantitative differences in hemilabile behavior of the phosphino-thioether ligands, depending on the substituent at sulfur. Clusters [1]PF6, [2]PF6 and [3]PF6 were tested as catalysts in reduction of nitrobenzene to aniline with Ph2SiH2 under mild conditions. Significant differencies in the catalytic activity were observed, which can be attributed to different hemilabile behavior of the PS1 and PS2/PS3 ligands

    Synthetic Fragments of Receptor for Advanced Glycation End Products Bind Beta-Amyloid 1–40 and Protect Primary Brain Cells From Beta-Amyloid Toxicity

    Get PDF
    Receptor for advanced glycation end products (RAGE) is involved in the pathogenesis of Alzheimer’s disease. We have previously revealed that RAGE fragment sequence (60–76) and its shortened analogs sequence (60–70) and (60–65) under intranasal insertion were able to restore memory and improve morphological and biochemical state of neurons in the brain of bulbectomized mice developing major AD features. In the current study, we have investigated the ability of RAGE peptide (60–76) and five shortened analogs to bind beta-amyloid (Aβ) 1–40 in an fluorescent titration test and show that all the RAGE fragments apart from one [sequence (65–76)] were able to bind Aβ in vitro. Moreover, we show that all RAGE fragments apart from the shortest one (60–62), were able to protect neuronal primary cultures from amyloid toxicity, by preventing the caspase 3 activation induced by Aβ 1–42. We have compared the data obtained in the present research with the previously published data in the animal model of AD, and offer a probable mechanism of neuroprotection of the RAGE peptide

    OpenForecast: An Assessment of the Operational Run in 2020–2021

    No full text
    OpenForecast is the first openly available national-scale operational runoff forecasting system in Russia. Launched in March 2020, it routinely provides 7-day ahead predictions for 834 gauges across the country. Here, we provide an assessment of the OpenForecast performance on the long-term evaluation period from 14 March 2020 to 31 October 2021 (597 days) for 252 gauges for which operational data are available and quality-controlled. Results show that OpenForecast is a robust system based on reliable data and solid computational routines that secures efficient runoff forecasts for a diverse set of gauges

    Interference control of transmittance and absorption in ultrathin metal films in the presence of a two-wave field

    No full text
    The focus of research in this article is the reflection, transmission and absorption of microwave radiation by nanometer metal films under oblique incidence of two counter-propagating coherent waves on the opposite surfaces of the film. We demonstrate that at certain values of the angle of incidence and of film thickness the film transmittance can be increased by several orders of magnitude which results in the “lightening” of the metal film. As part of this article’s analysis, we determine the values of film thickness and the angles of incidence at which the near total absorption of incident power is possible

    Performance evaluation for blind methods of noise characteristic estimation for TerraSAR-X images

    No full text
    International audienceEstimation of noise characteristics is used in various image processing tasks such as edge detection, filtering, reconstruction, compression and segmentation, etc. It is very desirable to have as accurate as possible estimated noise characteristics which influence the quality of further processing. This paper deals with evaluation of accuracy of earlier proposed methods for blind estimation of speckle characteristics. Evaluation is done for TerraSAR-X single-look amplitude images. It is shown that the obtained estimates depend upon image complexity. Besides, parameters of any estimation method influence accuracy (bias) as well. Finally, spatial correlation of noise is yet another factor affecting the obtained estimates. As it is demonstrated, blind estimation in aggregate allows to obtain the estimates of speckle variance with relative error up to 20%, which is appropriate for practical needs. Besides, if speckle variance is estimated, it becomes possible to get accurate estimates of noise spatial correlation in DCT domain. Such estimates can be used in e. g. DCT-based filtering of SAR images

    Chemically Bound Resorbable Ceramics as an Antibiotic Delivery System in the Treatment of Purulent–Septic Inflammation of Bone Tissue

    No full text
    Local drug delivery systems are an effective approach in the treatment of purulent–septic inflammation of bone tissue. Chemically bonded multiphase ceramics based on calcium-deficient carbonate-substituted hydroxyapatite combine resorbability, osteoconductivity, and the possibility of volumetric incorporation of antibiotics. Macroporosity is regulated by the concentration of polyethylene glycol granules introduced into the initial powder composition, followed by their extraction. The selected conditions for the consolidation of the ceramic matrix and the extraction of PEG granules retain the activity of vancomycin, which is confirmed by the results of microbiological studies. The concentration of vancomycin and the porosity affect the local concentration and release of the antibiotic. The incorporation method provides a prolonged release of the antibiotic for up to 31 days. In vivo experiments with bone implantation have shown that chemically bound macroporous ceramics with incorporated vancomycin are a therapeutically effective carrier of the substance during the healing of bone defects in conditions of surrounding purulent–septic inflammation, and can be considered as a carrier for local antibacterial therapy, at the site of implantation
    corecore