52 research outputs found

    The dependence of cylindrical resonator natural frequencies on the fluid density

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    The article examines the dependence of cylindrical resonator natural frequencies (sensitive element) on the density (mass) of different fluids flowing through it. The cylindrical resonators are being widely applied in automatic control systems of technological processes as oscillating transducer density meter. The article presents the experimental results that prove the dependence of natural frequencies and vibration amplitude on the fluid density

    Direct Catalytic Reduction of SO2 by CH4 over Fe-Mn Catalysts Prepared by Granulation of Ferromanganese Nodules

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    The chemical, textural, structural and strength properties of ferromanganese nodules and granulated Fe-Mn catalysts containing such nodules were studied. It was found that the granulated catalysts have a developed pore structure, which is close to that of the starting material, and surpass the starting material in strength parameters. The catalysts were tested in desulfurization by methane at a stoichiometric ratio SO2/CH4 = 2. The testing showed that Fe-Mn catalysts with the oxide or sulfide form of active components are active in desulfurization by methane and can selectively reduce SO2 with a conversion above 80%

    Synthesis of Nanoscale TiO2 and Study of the Effect of Their Crystal Structure on Single Cell Response

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    To study the effect of nanoscale titanium dioxide (TiO2) on cell responses, we synthesized four modifications of the TiO2 (amorphous, anatase, brookite, and rutile) capable of keeping their physicochemical characteristics in a cell culture medium. The modifications of nanoscale TiO2 were obtained by hydrolysis of TiCl4 and Ti(i-OC3H7)4 (TIP) upon variation of the synthesis conditions; their textural, morphological, structural, and dispersion characteristics were examined by a set of physicochemical methods: XRD, BET, SAXS, DLS, AFM, SEM, and HR-TEM. The effect of synthesis conditions (nature of precursor, pH, temperature, and addition of a complexing agent) on the structural-dispersion properties of TiO2 nanoparticles was studied. The hydrolysis methods providing the preparation of amorphous, anatase, brookite, and rutile modifications of TiO2 nanoparticles 3–5 nm in size were selected. Examination of different forms of TiO2 nanoparticles interaction with MDCK cells by transmission electron microscopy of ultrathin sections revealed different cell responses after treatment with different crystalline modifications and amorphous form of TiO2. The obtained results allowed us to conclude that direct contact of the nanoparticles with cell plasma membrane is the primary and critical step of their interaction and defines a subsequent response of the cell

    Investigation of the Sorption Properties of Ore Materials for the Removal of Sulfur Dioxide from Exhaust Flue Gases of Power Plants

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    The prospects of using a natural material – ferromanganese nodules (FMN) from the Gulf of Finland – as the SO2 adsorbent are discussed. The starting material was studied as pellets and powder using X-ray fluorescence spectroscopy, XRD, BET, and mechanical strength analysis; dependences of physicochemical parameters of the material on heat treatment at 100-1000 ºC were found. FMN samples were tested in the process of SO2 sorption. The sorptive capacity of FMN samples for SO2 was found to increase with humidity of adsorbents; FMN samples with a humidity above 40% were shown to be promising for the removal of sulfur dioxide from gase

    Peripheral vascular lesions with the development of hand and foot skin necrosis in a patient with COVID-19: a case report

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    In the presented case report, 36-year-old female patient, who was hospitalized in the rheumatology department, developed thrombotic microangiopathy and sepsis-related coronavirus disease 2019 (COVID-19). In the department, hereditary thrombophilia was revealed: heterozygous polymorphism in the coagulation factor 5 gene (Factor V Leiden). Livedo reticularis. It is known that in October 2020, the patient had COVID-19 with bilateral pneumonitis on chest computed tomography. On examination, dry gangrene of 1, 2, 4, 5 fingers of the right hand, 2 finger of the left hand, as well as 2, 3, 4, 5 fingers of the right and left feet were diagnosed. Necrosis of the nasal tip. Surgery was performed with amputation of the affected fingers and distal feet with autodermoplasty

    A New and Fast Technique to Generate Offspring after Germ Cells Transplantation in Adult Fish: The Nile Tilapia (Oreochromis niloticus) Model

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    Background: Germ cell transplantation results in fertile recipients and is the only available approach to functionally investigate the spermatogonial stem cell biology in mammals and probably in other vertebrates. In the current study, we describe a novel non-surgical methodology for efficient spermatogonial transplantation into the testes of adult tilapia (O. niloticus), in which endogenous spermatogenesis had been depleted with the cytostatic drug busulfan. Methodology/Principal Findings: Using two different tilapia strains, the production of fertile spermatozoa with donor characteristics was demonstrated in adult recipient, which also sired progeny with the donor genotype. Also, after cryopreservation tilapia spermatogonial cells were able to differentiate to spermatozoa in the testes of recipient fishes. These findings indicate that injecting germ cells directly into adult testis facilitates and enable fast generation of donor spermatogenesis and offspring compared to previously described methods. Conclusion: Therefore, a new suitable methodology for biotechnological investigations in aquaculture was established, with a high potential to improve the production of commercially valuable fish, generate transgenic animals and preserv

    Safety and efficacy of convalescent plasma for COVID-19: the preliminary results of a clinical trial

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    Background. The lack of effective etiotropic therapy for COVID-19 has prompted researchers around the globe to seekr various methods of SARS-CoV-2 elimination, including the use of convalescent plasma. Aim. The aim of this work was to study the safety and efficacy of the convalescence plasma treatment of severe COVID-19 using the plasma containing specific antibodies to the receptor binding domain (RBD) of SARS-CoV-2 S protein in a titer of at least 1:1000. Methods. A single-center, randomized, prospective clinical study was performed at the FRCC FMBA of Russia with the participation of 86 patients who were stratified in two groups. The first group included 20 critically ill patients who were on mechanical ventilation the second group included 66 patients with moderate to severe COVID-19 and with spontaneous respiration. The patients in the second group were randomized into two cohorts in a ratio of 2:1. In the first cohort (46 patients), pathogen-reduced convalescent plasma was transfused (twice, 320 ml each), in the second cohort (20 patients) a similar amount of non-immune freshly frozen plasma was transfused to the patients. Results. The use of plasma of convalescents in patients with severe COVID-19 being on mechanical ventilation does not affect the disease outcome in these patients. The mortality rate in this group was 60%, which corresponds to the average mortality of COVID patients on mechanical ventilation in our hospital. In the second group, clinical improvement was detected in 75% and 51%, for convalescent and non-immune plasma, respectively. Of the 46 people who received convalescent plasma, three patients (6.5%) were transferred to mechanical ventilation, two of them died. In the group receiving non-immune plasma, the need for mechanical ventilation also arose in three patients (15%), of which two died. The hospital mortality in the group of convalescent plasma was 4.3%, which is significantly lower than the average COVID-19 hospital mortality at our Center (6.73%) and more than two times lower than the hospital mortality in the control group (n=150), matched by age and by the disease severity. Conclusions. Thus, we demonstrated a relative safety of convalescent plasma transfusion and the effectiveness of such therapy for COVID-19 at least in terms of the survival of hospitalized patients with severe respiratory failure without mechanical ventilation. In the absence of bioengineered neutralizing antibodies and effective etiotropic therapy, the use of hyperimmune convalescent plasma is the simplest and most effective method of specific etiopathogenetic therapy of severe forms of COVID-19

    Eribulin-trastuzumab combination in HER2-positive metastatic breast cancer: updated results from a Russian observational study

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    Introduction. The standard of 1st line treatment of HER2+ metastatic breast cancer (mBC) is double blockade with trastuzumab and pertuzumab + taxane, 2nd line – Trastuzumab-emtazine. There are no standards for further treatment, as well as the optimal drug sequence. Expansion of the arsenal of therapeutic possibilities and the use of new combinations will certainly improve the results of treatment of this category of patients and increase their life expectancy.Aim. We sought to describe treatment patterns of  eribulin  and clinical outcomes of  metastatic HER2-positive breast cancer treated with eribulin  plus trastuzumab combination in  academic institutions and community oncology practices across the Russian Federation.Materials and methods. Patients treated with eribulin anytime between Jan, 2014 and Sep, 2019 with a diagnosis of MBC were identified by 23 providers from Russia. Providers retrospectively reviewed the health records and abstracted selected data points into an electronic case report form for each eligible patient.Results. 100 HER2-positive pts received eribulin in combination with trastuzumab. Median age was 55 (31–80) yrs and ECOG status 0–3. 67% pts had visceral metastases. Eribulin was administered as 1st and 2nd line to 23 (23%) pts, 3rd line to 31 (31%) pts, 4th line and later to 46 (46%). Median number of cycles was 5 (2–27). ORR was 12%, SD – 72%, SD > 6 months – 23%, PD – 16%. Clinical efficacy rate achieved in 35%. Median PFS was 5.07 months (95% CI 4.021–6.119). According to the ER-status the response to eribulin and trastuzumab was different. ORR was 18.8%, SD 72.9% in pts with ER-positive MBC (n = 48) and 5.8% and 71.2% respectively in ER-negative MBC (n = 52). Median PFS was 6.97 months (95% CI 3.924–10.016) in pts with ER-positive MBC and 4.67 months (95% CI 3.841–5.499) in ER-negative MBC (р = 0.3). The combination was well tolerated: dose reductions were required in 12% pts, withdrawal due to toxicity in 4% pts. The most common type of toxicity was hematological with neutropenia Gr III-IV in 14 (14%) pts. Peripheral neuropathy Gr III was observed in 5 (5%) pts. No cardiotoxicity was detected.Conclusions. This is the real-life data of clinical outcomes for patients receiving eribulin plus trastuzumab for HER2-positive MBC throughout the Russian Federation. Our experience with eribulin plus trastuzumab demonstrates that this combination may be a potential effective treatment option for HER-2 positive MBC patients
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