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Annals of Parasitology 2020The review provides data on species composition of nematodes in 50 species of birds from Armenia (South of Lesser Caucasus). Most of the studied birds belong to...
The review provides data on species composition of nematodes in 50 species of birds from Armenia (South of Lesser Caucasus). Most of the studied birds belong to Passeriformes and Charadriiformes orders. One of the studied species of birds (Larus armenicus) is an endemic. The taxonomy and host-specificity of nematodes reported in original papers are discussed with a regard to current knowledge about this point. In total, 52 nematode species parasitizing birds in Armenia are reported. Most of the reported species of nematodes are quite common in birds outside of Armenia. One species (Desmidocercella incognita from great cormorant) was first identified in Armenia. Great snipe was recorded as a new host for Hystrichis tricolor. Zoonotic nematode Trichinella pseudospiralis was reported in Armenia from Eurasian blackbird.
Topics: Animals; Armenia; Nematoda; Passeriformes
PubMed: 33646734
DOI: 10.17420/ap6604.285 -
Acta Naturae 2021The coronavirus disease outbreak in 2019 (COVID-19) has now achieved the level of a global pandemic and affected more than 100 million people on all five continents and...
The coronavirus disease outbreak in 2019 (COVID-19) has now achieved the level of a global pandemic and affected more than 100 million people on all five continents and caused over 2 million deaths. Russia is, needless to say, among the countries affected by SARS-CoV-2, and its health authorities have mobilized significant efforts and resources to fight the disease. The paper presents the result of a functional analysis of 155 patients in the Moscow Region who were examined at the Central Clinical Hospital of the Russian Academy of Sciences during the first wave of the pandemic (February-July, 2020). The inclusion criteria were a positive PCR test and typical, computed tomographic findings of viral pneumonia in the form of ground-glass opacities. A clinical correlation analysis was performed in four groups of patients: (1) those who were not on mechanical ventilation, (2) those who were on mechanical ventilation, and (3) those who subsequently recovered or (4) died. The correlation analysis also considered confounding comorbidities (diabetes, metabolic syndrome, hypertension, etc.). The immunological status of the patients was examined (levels of immunoglobulins of the M, A, G classes and their subclasses, as well as the total immunoglobulin level) using an original SARS-CoV-2 antibody ELISA kit. The ELISA kit was developed using linear S-protein RBD-SD1 and NTD fragments, as well as the N-protein, as antigens. These antigens were produced in the prokaryotic system. Recombinant RBD produced in the eukaryotic CHO system (RBD CHO) was used as an antigen representing conformational RBD epitopes. The immunoglobulin A level was found to be the earliest serological criterion for the development of a SARS-CoV-2 infection and it yielded the best sensitivity and diagnostic significance of ELISA compared to that of class M immunoglobulin. We demonstrated that the seroconversion rate of "early" N-protein-specific IgM and IgA antibodies is comparable to that of antibodies specific to RBD conformational epitopes. At the same time, seroconversion of SARS-CoV-2 N-protein-specific class G immunoglobulins was significantly faster compared to that of other specific antibodies. Our findings suggest that the strong immunogenicity of the RBD fragment is for the most part associated with its conformational epitopes, while the linear RBD and NTD epitopes have the least immunogenicity. An analysis of the occurrence rate of SARS-CoV-2-specific immunoglobulins of different classes revealed that RBD- and N-specific antibodies should be evaluated in parallel to improve the sensitivity of ELISA. An analysis of the immunoglobulin subclass distribution in sera of seropositive patients revealed uniform induction of N-protein-specific IgG subclasses G1-G4 and IgA subclasses A1-A2 in groups of patients with varying severity of COVID-19. In the case of the S-protein, G1, G3, and A1 were the main subclasses of antibodies involved in the immune response.
PubMed: 33959390
DOI: 10.32607/actanaturae.11374 -
Pathophysiology : the Official Journal... Apr 2022Cardiopulmonary disorders cause a significant increase in the risk of adverse events in patients with COVID-19. Therefore, the development of new diagnostic and...
Cardiopulmonary disorders cause a significant increase in the risk of adverse events in patients with COVID-19. Therefore, the development of new diagnostic and treatment methods for comorbid disorders in COVID-19 patients is one of the main public health challenges. The aim of the study was to analyze patient survival and to develop a predictive model of survival in adults with COVID-19 infection based on transthoracic echocardiography (TTE) parameters. We conducted a prospective, single-center, temporary hospital-based study of 110 patients with moderate to severe COVID-19. All patients underwent TTE evaluation. The predictors of mortality we identified in univariate and multivariable models and the predictive performance of the model were assessed using receiver operating characteristic (ROC) analysis and area under the curve (AUC). The predictive model included three factors: right ventricle (RV)/left ventricle (LV) area (odds ratio (OR) = 1.048 per 1/100 increase, p = 0.03), systolic pulmonary artery pressure (sPAP) (OR = 1.209 per 1 mm Hg increase, p < 0.001), and right ventricle free wall longitudinal strain (RV FW LS) (OR = 0.873 per 1% increase, p = 0.036). The AUC-ROC of the obtained model was 0.925 ± 0.031 (95% confidence interval (95% CI): 0.863−0.986). The sensitivity (Se) and specificity (Sp) measures of the models at the cut-off point of 0.129 were 93.8% and 81.9%, respectively. A binary logistic regression method resulted in the development of a prognostic model of mortality in patients with moderate and severe COVID-19 based on TTE data. It may also have additional implications for early risk stratification and clinical decision making in patients with COVID-19.
PubMed: 35645324
DOI: 10.3390/pathophysiology29020014 -
Nanoscale interface confinement of ultrafast spin transfer torque driving non-uniform spin dynamics.Nature Communications Apr 2017Spintronics had a widespread impact over the past decades due to transferring information by spin rather than electric currents. Its further development requires...
Spintronics had a widespread impact over the past decades due to transferring information by spin rather than electric currents. Its further development requires miniaturization and reduction of characteristic timescales of spin dynamics combining the sub-nanometre spatial and femtosecond temporal ranges. These demands shift the focus of interest towards the fundamental open question of the interaction of femtosecond spin current (SC) pulses with a ferromagnet (FM). The spatio-temporal properties of the impulsive spin transfer torque exerted by ultrashort SC pulses on the FM open the time domain for probing non-uniform magnetization dynamics. Here we employ laser-generated ultrashort SC pulses for driving ultrafast spin dynamics in FM and analysing its transient local source. Transverse spins injected into FM excite inhomogeneous high-frequency spin dynamics up to 0.6 THz, indicating that the perturbation of the FM magnetization is confined to 2 nm.
PubMed: 28406144
DOI: 10.1038/ncomms15007 -
Optics Express Jan 2017Scintillator-based X-ray imaging is a powerful technique for noninvasive real-space microscopic structural investigation such as synchrotron-based computed tomography....
Scintillator-based X-ray imaging is a powerful technique for noninvasive real-space microscopic structural investigation such as synchrotron-based computed tomography. The resolution of an optical image formed by scintillation emission is fundamentally diffraction limited. To overcome this limit, stimulated scintillation emission depletion (SSED) X-ray imaging, based on stimulated emission depletion (STED) microscopy, has been recently developed. This technique imposes new requirements on the scintillator material: efficient de-excitation by the STED-laser and negligible STED-laser excited luminescence. In this work, luminescence depletion was measured in several commonly-used Ce, Tb, and Eu - doped scintillators using various STED lasers. The depletion of Tb and Eu via 4f-4f transitions was more efficient (P = 8…19 mW) than Ce depletion via 5d-4f transitions (P = 43…45 mW). Main origins of STED-laser excited luminescence were one- and two-photon excitation, and scintillator impurities. LSO:Tb scintillator and a 628 nm cw STED-laser is the most promising combination for SSED satisfying the above-mentioned requirements.
PubMed: 28158009
DOI: 10.1364/OE.25.001251 -
Archives of Razi Institute Nov 2021Nowadays, it is difficult to find a more complicated inflammatory disease of the abdominal organs in its pathogenesis than acute pancreatitis (AP). The application of...
Nowadays, it is difficult to find a more complicated inflammatory disease of the abdominal organs in its pathogenesis than acute pancreatitis (AP). The application of antimediatory drugs and antimetabolites is the most promising direction in the correction of inflammatory pathological processes. The study of possible applications of a new group of drugs (monoclonal antibodies) that may trigger inflammation is also of great interest. The present study aimed to study the effect of infliximab on the lethality, volume, and nature of pancreatic lesions in severe necrotizing ductal pancreatic necrosis. The study was conducted on female Wistar rats (n=30) of similar age in the weight range of 200-250g. All manipulations were performed under general anesthesia by intraperitoneal injection of zoletil at a dose of 60 mg/kg, as well as chloral hydrate at a dose of 125 mg/kg. Model of severe acute necrotizing pancreatitis was performed through the injection of 0.5 ml of a buffer solution containing a bile acid salt-sodium taurocholate introductory. The animals were divided into the following groups: Group A (n=6): normal values; Group B (n=6): the mortality study was conducted in acute destructive pancreatitis in a period of 24 h; Group C (n=6): the simulation of acute severe necrotic pancreatitis was performed in this group along with the study of the volume of pancreatic lesions for a period of 6 h from the moment of modeling; Group D (n=6): in this group, the effect of infliximab (at a dose of 60 mkg/kg) was studied on mortality in severe destructive pancreatitis for a period of 24 h from the moment of modeling; Group E (n=6): in this group, the effect of infliximab (at a dose of 120 mkg/kg) was studied on the volume of pancreatic lesions in severe destructive pancreatitis for a period of 6 h from the moment of modeling. During the assessment of pancreatic damage, the mean±SD volume of pancreatic lesions was determined to be 34.8%±1.2% in a period of 6 h after modeling. Assessment of pancreatic damage in group E and the protective effect of infliximab at a dose of 60 mg/kg showed that the total volume of the necrotic pancreatic lesion was determined to be 21.3%±1.4% after a period of 6 h from the moment of AP modeling. In the course of this study, it was revealed that the application of infliximab at a dose of 60 mcg/kg led to a pronounced positive effect on the pancreatic lesion, manifested by up to 50% decrease in mortality for one day in group D. Infliximab had a definite protective effect in AP, decreasing the volume of the injury, as well as the mortality rate by half for 24 h. Therapy with anti-tumor necrosis factor with infliximab could significantly reduce the volume of pancreatic lesions in severe forms of pancreatic necrosis, which contributed to a pronounced decrease in mortality for 1 day from the moment of pathology reproduction.
Topics: Animals; Female; Rats; Acute Disease; Infliximab; Pancreatitis, Acute Necrotizing; Rats, Wistar
PubMed: 35355779
DOI: 10.22092/ari.2021.355845.1726 -
The Science of the Total Environment Jun 2024The increasing popularity and recognition of citizen science approaches to monitor soil health have promoted the idea to assess soil microbial decomposition based on a...
The increasing popularity and recognition of citizen science approaches to monitor soil health have promoted the idea to assess soil microbial decomposition based on a standard litter sample - tea bags. Although tea bag initiatives are expanding across the world, the global datasets remain biased in regard to investigating regions and biomes. This study aimed to expand the tea bag initiative to European Russia, which remains a "white spot" on the tea bag index map. We also added urban soils into the analysis, which were underestimated previously. We compared the standard and local tea brands to explore possible adaptations of the standard approach to regions with limited access to standard tea brands. The established monitoring network included natural and urban sites in six vegetation zones along a 3000 km latitudinal gradient. There was a very close linear relationship (R = 0.94-0.98) in the mass loss of alternative and standard tea litter. The mass loss of green tea in soil along the latitudinal gradient showed an increasing trend from north to south. Variations in the microbial decomposition of green tea were mainly explained by the latitudinal gradient, with low soil temperature identified as key factors hampering decomposition. Mass loss of the more recalcitrant rooibos tea was mainly determined via land use, with decomposition rates on average 1.3 times higher in urban soils. This pattern was in line with higher soil temperatures and pH in urban sites compared to natural counterparts. The findings of our study could prove valuable in extending the tea bag network of soil decomposition assessment into broader territories, including urban areas. Additionally, they could facilitate the involvement of citizen science and complete the database for C cycle modeling depending on climatic conditions.
Topics: Russia; Environmental Monitoring; Soil; Tea; Soil Microbiology
PubMed: 38531454
DOI: 10.1016/j.scitotenv.2024.171881 -
Optics Express Jan 2017X-ray microtomography is a widely applied tool for noninvasive structure investigations. The related detectors are usually based on a scintillator screen for the fast in...
X-ray microtomography is a widely applied tool for noninvasive structure investigations. The related detectors are usually based on a scintillator screen for the fast in situ conversion of an X-ray image into an optical image. Spatial resolution of the latter is fundamentally diffraction limited. In this work, we introduce stimulated scintillation emission depletion (SSED) X-ray imaging where, similar to stimulated emission depletion (STED) microscopy, a depletion beam is applied to the scintillator screen to overcome the diffraction limit. The requirements for the X-ray source, the X-ray flux, the scintillator screen, and the STED beam were evaluated. Fundamental spatial resolution limits due to the spread of absorbed X-ray energy were estimated with Monte Carlo simulations. The SSED proof-of-concept experiments demonstrated 1) depletion of X-ray excited scintillation, 2) partial confinement of scintillating regions to sub-diffraction sized volumes, and 3) improvement of the imaging contrast by applying SSED.
PubMed: 28157955
DOI: 10.1364/OE.25.000654