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With the transition of mining operations to deeper horizons, the safety of miners in coal mines is significantly reduced. This is mainly due to the manifestation of gas-dynamic and the thermische factors, the first of which include sudden emissions of coal and gas, gas venting, shock and detonation waves in the atmosphere of mine workings. The reasons for the thermal factors are the presence of dust-gas-air mixtures prone to chemical oxidation reactions of carbonaceous substances, and the formation of self-heating foci, which lead to changes in the temperature field in the atmosphere of mountain rocks and their surroundings, which significantly increases the probability of occurrence of deflagration and detonation processes. In this paper, the parameters of the shock front in a viscous heat-conducting gas-air flow formed by a sudden release of gas from an underground tank into a mine with a supersonic speed are determined. It is assumed that the movement of the gas-air mixture during the transition of the shock front is stationary, which made it possible to use the fundamental laws of conservation of mass, pulses and energy. The formulas determining the parameters of the gas-air flow are obtained, their graphs are constructed and some regularities of the flow parameters change behind the shock front depending on the initial Mach number and the Poisson adiabatic index are revealed.

Introduction: Respiratory infections, collectively, are one of the World's most common and serious illness groups. As recent observations have shown, the most severe courses of acute respiratory infection, often leading to death, are due to uncontrolled cytokine production (hypercytokinemia)., Methods: The study involved 364 patients with respiratory illness being treated in clinics in St. Petersburg (Russia) in 2018-2019 and 30 healthy controls. Cytokine analysis was carried out in the acute phase of illness (2-3 days from onset of initial symptoms) and in the stage of recovery (days 9-10). The research presented is devoted to the assessment of mRNA expression of specific cytokines (interleukin [IL]-1b, IL-2, IL-4, IL-6, IL-8, IL-10, IL-18, tumor necrosis factor-α [TNF-α], and interferon-λ) and MxA in whole blood leukocytes, by means of real-time polymerase chain reaction., Results: In 70% of patients, bacterial or viral pathogens were identified, with influenza viral infections (types A and B) prevailing. Significant increases in the expression of IL-18, TNF, and IL-10 were observed, relative to controls, only with influenza viral infections. We have shown a difference in IL-6 mRNA expression in patients with bacterial or viral pathogens. No statistically significant difference was found in white blood cells IL-4 expression levels between patients and healthy controls., Conclusion: Investigation of the nuances of systemic cytokine production, in response to specific viral and bacterial pathogens, makes it possible to assess the risks of developing hypercytokinemia during respiratory infection with agents circulating in the human population and to predict the pathogenicity and virulence of circulating threats., Competing Interests: There are no conflicts of interest., (Copyright: © 2022 Journal of Global Infectious Diseases.)

Two influenza A nucleoprotein variants (wild-type: G102R; and mutant: G102R and E292G) were studied with regard to macro-molecular interactions in oligomeric form (24-mers). The E292G mutation has been previously shown to provide cold adaptation. Molecular dynamics simulations of these complexes and trajectory analysis showed that the most significant difference between the obtained models was distance between nucleoprotein complex strands. The isolated complexes of two ribonucleoprotein variants were characterized by transmission electron microscopy and differential scanning fluorimetry (DSF). Presence of the E292G substitution was shown by DSF to affect nucleoprotein complex melting temperature. In the filament interface peptide model, it was shown that the peptide corresponding in primary structure to the wild-type NP (SGYDF E REGYS) is prone to temperature-dependent self-association, unlike the peptide corresponding to E292G substitution (SGYDF G REGYS). It was also shown that the SGYDF E REGYS peptide is capable of interacting with a monomeric nucleoprotein (wild type); this interaction's equilibrium dissociation constant is five orders of magnitude lower than for the SGYDF G REGYS peptide. Using small-angle neutron scattering (SANS), the supramolecular structures of isolated complexes of these proteins were studied at temperatures of 15, 32, and 37 °C. SANS data show that the structures of the studied complexes at elevated temperature differ from the rod-like particle model and react differently to temperature changes. The data suggest that the mechanism behind cold adaptation with E292G is associated with a weakening of the interaction between strands of the ribonucleoprotein complex and, as a result, the appearance of inter-chain interface flexibility necessary for complex function at low temperature.Communicated by Ramaswamy H. Sarma.

Upper respiratory tract infections are the world's most common infectious disease. The etiologic agents behind upper respiratory tract infections (URTIs) are, in fact, a diverse set of pathogens such as influenza, parainfluenza, adenovirus, rhinovirus, and others. More than 200 pathogens are known to be involved. Differential diagnosis of viral infections is sometimes complicated by their diversity or similarity of clinical presentation. This work is devoted to the development of a method which enables simultaneous detection of six common viral URTI pathogens: IAV; IBV; RSV; hAdV; hPIV2; and hPIV3. Antibody microarray technology is utilized to accomplish the analysis. In preparation for protein microchip creation, we produced, characterized, and selected approximately 50 monoclonal antibodies; for each of the aforementioned pathogens, an optimal monoclonal antibody pair was selected. A protein microchip was created, and its core working conditions were optimized. With a balance between convenience and maximal assay sensitivity in mind, a one-step analysis approach was developed for accomplishing the ELISA-like "sandwich" interaction on the manufactured microchip (antibody microarray). Reference viral strains were used to establish the lower limits of detection (LoD) for the assay. For IAV, the LoD was 0.25 ng/ml total viral protein. For other viruses, the LoD ranged from 1 to 2 ng/ml total protein. These sensitivity limits are slightly better than those of standard ELISA, but inferior to those of PCR. Overall, we believe that the developed microchip is a good alternative to existing methods, allowing relatively quick (overnight), inexpensive, simultaneous screening of several pathogens. The design of the antibody microarray is conducive to further development, and the panel of analyzed pathogens can be expanded to include approximately 50 members., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Objective: To study correlations between the clinical signs of dysfunction and pathological structural changes in the renal parenchyma in a group of Russian patients with AL amyloidosis in 2008-2015., Subjects and Methods: A total group (At) including Group 1 with AL (kappa + lambda light chains) ( n =46) was divided into subgroups: 2λ) 40 patients with AL-lambda (AL-λ); 3κ) 6 patients with AL-kappa (AL-κ). All the patients underwent standard laboratory and instrumental studies: determinations of the peak systolic and diastolic blood pressures (SBP and DBP, respectively, mm Hg), glomerular filtration rate (GFR) (ml/min/1.73 m 2 ) by the EPI equation, daily protein loss (g/day). Polyclonal antibodies against kappa and lambda light chains, AA component, and transthyretin (DAKO, Denmark) were used as immunomorphological markers. Light optical structural changes were semiquantitatively assessed, by ranking the following analyzed sign: interstitial focal sclerosis (FS), tubular atrophy (TA), interstitial inflammatory infiltration (II) semi-quantitatively (0 - no; 1 - < 25%; 2 - <50%, 3 - >50% of the volume of a histological compartment). Glomerulosclerosis (GS) was defined as the percentage of sclerotic glomeruli. The extent of amyloid depositions in the renal parenchyma structures was estimated according to the procedure proposed by Ying Yao et al., 2013., Results: The AL group showed a female preponderance (65.21%). The patients' mean age was 62±11 years. There were no significant differences in daily proteinuria and the levels of serum creatinine, GFR, SBP, and DBP between the groups. The predominant clinical manifestation in the patients was nephrotic syndrome. A comparative analysis of the pathomorphological criteria for the spread of amyloid masses and the markers of fibroplastic processes revealed no statistically significant differences in the studied groups. Correlation analysis of the spread of AL deposits in the renal parenchyma in the patients of Group 1 and Subgroup 2λ, as well as laboratory data showed that there were significant ( p <0.05) correlations with GFR, serum creatinine, unlike in Subgroup 3κ. At the same time, the analysis demonstrated that daily proteinuria had a significant positive correlation with VA, IA, GA, and TA values in Subgroup 3κ, unlike in Group 1 and Subgroup 2λ. Positive correlations were found between glomerulosclerosis and VA in Subgroup 2 λ and IA in Group 1. Sclerotic (FS and TA) changes in the tubular interstitium (TIN) were significantly positively correlated with all the indicators of AL (GA, VA, IA, TA) in the examinees in Group 1 and Subgroup 2λ, but not in Subgroup 3κ. Inflammatory TIN infiltration showed statistically significant ( p <0.05) positive correlations with IA and VA in Group 1 and Subgroup 2λ and their absence in subgroup 3κ., Conclusion: : The retrospective analysis of nephrobiopsy specimens from of patients with AL amyloidosis revealed that kidney damage was mainly associated with the development of λ-associated AL amyloidosis. The clinical and laboratory parameters were correlated with the pathomorphological criteria for loading the renal parenchyma with amyloid masses. The findings suggest that there are clinical and morphological features of the subclasses of AL amyloidosis, which may be of value for predicting the course and progression of the disease.

Anti-influenza drugs and vaccines have a limited effect due to the high mutation rate of virus genome. The direct impact on the conservative virus genome regions should significantly improve therapeutic effectiveness. The RNA interference mechanism (RNAi) is one of the modern approaches used to solve this problem. In this work, we have investigated the antiviral activity of small interfering RNA (siRNA) against the influenza A/PR/8/34 (H1N1), targeting conserved regions of NP and PA. Polycations were used for intracellular siRNA delivery: chitosan's derivatives (methylglycol and quaternized chitosan), polyethyleneimine, lipofectamine, and hybrid organic/non-organic microcapsules. A comparative study of these delivery systems with fluorescent labeled siRNA was conducted. The antiviral activity of three small interfering RNAs targeting the NP (NP-717, NP-1496) and PA (PA-1630) influenza A viruses genes was demonstrated, depending on the chosen carrier. The most effective intracellular delivery and antiviral activity were observed for hybrid microcapsules.