Vaccination against COVID-19 is the most effective method of controlling the spread of SARS-CoV-2 and reducing mortality from this disease. The development of vaccines with high protective activity ...against a wide range of SARS-CoV-2 antigenic variants remains relevant. In this regard, evaluation of the effectiveness of physical methods of virus inactivation, such as ultraviolet irradiation (UV) of the virus stock, remains relevant. This study demonstrates that the UV treatment of SARS-CoV-2 completely inactivates its infectivity while preserving its morphology, antigenic properties, and ability to induce the production of virus-neutralizing antibodies in mice through immunization. Thus, the UV inactivation of SARS-CoV-2 makes it possible to obtain viral material similar in its antigenic and immunogenic properties to the native antigen, which can be used both for the development of diagnostic test systems and for the development of an inactivated vaccine against COVID-19.
•Waking is increased and slow wave sleep is decreased in the dark period in mice deficient for Panx1.•Movement activity is increased throughout the light/dark cycle in mice deficient for Panx1.•The ...lack of pannexin modifies animal behavior in vertical and horizontal pole tests.
Pannexins are membrane channel proteins that play a role in a number of critical biological processes (Panchin et al., 2000; Shestopalov, Panchin, 2008). Among other cellular functions, pannexin hemichannels serve as purine nucleoside conduits providing ATP efflux into the extracellular space (Dahl, 2015), where it is rapidly degraded to adenosine. Pannexin1 (Panx1) is abundantly expressed in the brain and has been shown to contribute to adenosine signaling in nervous system tissues (Prochnow et al., 2012). We hypothesized that pannexin1 may contribute to sleep-wake cycle regulation through extracellular adenosine, a well-established paracrine factor in slow wave sleep. To investigate this link, EEG and movement activity throughout the light/dark cycle were compared in Panx1−/− and Panx1+/+ mice. We found a significant increase in waking and a correspondent decrease in slow wave sleep percentages in the Panx1−/− animals. These changes were especially pronounced during the dark period. Furthermore, we found a significant increase in movement activity of Panx1−/− mice. These findings are consistent with the hypothesis that extracellular adenosine is relatively depleted in Panx1−/− animals due to the absence of the ATP-permeable hemichannels. At the same time, sleep rebound after a 6-h sleep deprivation remained unchanged in Panx1−/− mice as compared to the control animals. Behavioral tests revealed that Panx1−/− mice were significantly faster during their descent along the vertical pole but more sluggish during their run through the horizontal pole as compared to the control mice.
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A modified method for culturing, concentrating, and purifying phage ϕ24B preparations was developed. In particular, a new lysogenic phage-producing strain lacking flagella was used, induction ...conditions were optimized, and purification in a sucrose gradient followed by concentration by deposition on a Freon 113 cushion were used. Using this method, a preparation of the Stx-converting bacteriophage ϕ24B was obtained, suitable for CryoEM direct analysis. Based on CryoEM data for this phage, the first primary three-dimensional reconstruction of its virions was performed. The structure of the phage ϕ24B tail is described. It was shown that the adsorption apparatus of this virus is represented by six thin lateral fibrils, and an axial fibril located at the end of the tail. This arrangement of the tail structure is consistent with the previously proposed hypothesis based on analysis of the receptor binding proteins (RBPs) of this bacteriophage.
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The paper discusses modeling the dynamics of nickel concentration in soils, water, and the bottom sediments of lakes caused by atmospheric emissions from the Pechenganickel plant, Kola Peninsula, ...throughout its whole operation period. The applied technology of balanced identification makes it possible to use a mathematical description of heterogeneous geochemical processes in ecosystems to combine heterogeneous experimental data and build up a computer model with an optimal balance of its complexity and fitting quality of the data. The model is used to analyze the spatial and temporal variability of natural objects in the zone of distribution of atmospheric pollution (nickel) from the Pechenganickel plant. The paper presents and discusses results of this study, including estimates of the retrospective state of the simulated objects (before the start of the intense studies) and a forecast of their dynamics until 2030. According to the model calculations, the intensity of Ni accumulation in the soil and bottom sediments was 2.35 and 4.48 mg/(m
2
year) during the maximum deposition periods (1980–2005), whereas the model predicts a decrease in the intensity of Ni accumulation in the bottom sediments (0.23 mg/(m
2
year)) and slow Ni leaching from the soil (0.19 mg/(m
2
year)) after the shutdown of the plant.
Objective:
Isolation of bacteria and fungi from porcine nasal microbiome and evaluation of antibioticproducing potential among them.
Methods:
Conventional isolation using Sabouraud and Mueller-Hinton ...nutrient media was carried out for collected samples. The isolated strains were subjected to antibiotic susceptibility testing and antimicrobial activity screening.
Results and Discussion:
Taxonomy positions of the 20 isolated strains (18 bacteria, 1 yeast, 1 fungus) were determined by phylogenetic analysis, morphological study and a substrate utilization assay. Pseudomonas aeruginosa SM-11 was found to produce 4 known antibacterial molecules (pyocyanine, pyochelin, pyoluteorin, monorhamnolipid). Production of pyocyanine was induced by cocultivation with test microorganisms.
Conclusions:
The mammal microbiota might serve as a valuable source of antimicrobialproducing strains, including those of rare taxa. Cocultivation techniques are a promising approach to exploring antimicrobials from silent biosynthetic gene clusters.
•The improved thermal desorption diagnostics have been developed and tested in the Uragan-2M stellarator.•Using this diagnostics and mass-spectrometric method it was shown that hydrogen can be the ...one of the main gases which desorbs at the temperature of 250-300°C after discharge cleaning in hydrogen atmosphere.•Glow discharge cleaning with Ar plasma leads to Ar noticeable desorption from the stainless steel. Two kinds of desorbed Ar were registered with two different thermal desorption activation energies.
The improved thermal desorption diagnostics has been manufactured, installed and tested in the Uragan-2M (U-2M) stellarator 1-5 for in-situ characterisation a stainless steel (SS) wall outgassing rate and a number of molecular layers of residual gases on its surface in four different positions. The detailed description of this diagnostics, the location of thermal desorption stainless steel probes, the methodology of determining the outgassing rates and the number of molecular layers of residual gases on the probe surfaces are presented. It has been found that the difference between of the data taken from the probes being at different position in the U-2M vacuum chamber lies within the measurement accuracy. Using the present diagnostics together with the mass-spectrometer measurements, some studies were made to investigate the release of gases from the thermal desorption probes before and after radio frequency (RF) or glow discharge (GD) cleaning with hydrogen, helium and argon plasmas. It has been observed that hydrogen sorption by the SS probes surface during the discharge cleaning leads to significant hydrogen desorption even at the temperature of 250-300°C. In this case, hydrogen can be the one of the main gases which desorbs. After U-2M glow discharge cleaning with Ar plasma, the thermal desorption experiment has shown Ar as a significant component which is desorbed from the SS probe surface. Two kinds of desorbed Ar were registered with two different activation energies. The characteristics of the U-2M vacuum system are presented, too, including the block scheme, the list of pumps used to attain the ultimate vacuum, the equipment for measuring the total and partial pressures of residual gases.
The article discusses the structural and semantic features of a regional newspaper text on environmental topics. The material contains 30 texts from the socio-political newspaper “Rech” of the city ...of Cherepovets, Vologda Oblast, published during 2017 - the Year of Ecology in Russia. It is shown that the newspaper text on environmental topics has the structure of an inverted pyramid, when important information is presented at the beginning of the article, and detailing is presented in the second part; the photographs accompanying the texts have a different visual-grammatical structure and can be interpreted as one-part and two-part sentences. In the semantic aspect, it is revealed that a larger number of contextual synonymous pairs than sets are formed; gradual antonyms are used; lexical units are included that fix the anthropocentric model of the interaction of man and nature. It is identified that there is a two-way interaction between the environmental event and the text: the event is the basis for creating the text, and vice versa, a newspaper text covering an environmental problem may precede one event or another. It is indicated that the newspaper text on environmental topics is characterized by a homogeneous presentation of the material, anthropocentricity and polyphonicity; softening the presentation of problematic information is achieved through the use of literary synonyms, gradual antonyms and relevant illustrations.
In this work, a comparative analysis of the profile of fatty acids (
FA
) and volatile organic compounds (
VOCs
) for skimmed cow’s milk fermented by four different probiotic strains of
...Lacticasibacillu paracasei
(ABK, KF1, MA2, and MA3) was carried out. Analysis of FA and VOC profiles was performed using gas chromatography with mass spectrometric detection (
GC-MS
). For additional characterization of odor changes and its intensity in the fermented milk samples, the E-nose “electronic nose” odor analyzer was used. In total, the presence of 42 different FAs was detected in all samples, of which 17 were saturated, 8 monounsaturated, and 5 polyunsaturated. The strain-specific differences between the studied samples were of a complex nature and could not be explained only by the variation in the contribution of several individual FAs. The FA-nutritional indices characterizing the nutritional and biological value of the samples were different for milk fermented by different strains. Analysis of VOCs showed that the main odor-forming compounds in the studied samples were FAs and their reaction products, 2-heptanone, 2-nonanone, and 2-nonanol, which formed as a result of the following chain of transformations: β-oxidation → decarboxylation → reduction. The aroma of
L. paracasei
fermentation products, predicted on the basis of the odors of individual VOCs, generally coincided with their organoleptic assessment, a flavor typical of fermented milk (yogurt and curdled milk) with floral and fruity notes.
The aim of our trial was to evaluate the prognostic significance of qualitative ctDNA analysis on different stages of EGFR mutated non-small cell lung cancer (NSCLC) treatment.
We included 99 ...patients amendable for the first line treatment with either gefitinib/erlotinib (n = 87), afatinib (n = 10) or osimertinib (n = 2). Sequential qualitative analysis of ctDNA with cobas® EGFR Mutation Test v2 were performed before first dose, after 2 and 4 months of treatment, and on progression.
Our analysis showed clinically significant heterogeneity of EGFR-mutated NSCLC treated with 1st line tyrosine kinase inhibitors (TKIs) in terms of progression-free and overall survival. When treated with conventional approach, i.e. monotherapy with TKIs, the patients falls into three subgroups based on ctDNA analysis before and after 2 months of treatment. Patients without detectable ctDNA at baseline (N = 32) possess the best prognosis on duration of treatment (PFS: 24.07 16.8–31.3 and OS: 56.2 21.8–90.7 months). Those who achieve clearance after two months of TKI (N = 42) have indistinguishably good PFS (19.0 13.7 – 24.2). Individuals who retain ctDNA after 2 months (N = 25) have the worst prognosis (PFS: 10.3 7.0 – 13.5, p = 0.000). 9/25 patients did not develop ctDNA clearance at 4 months with no statistical difference in PFS from those without clearance at 2 months.
Prognostic heterogeneity of EGFR-mutated NSCLC should be taken into consideration in planning further clinical trials and optimizing the outcome of patients.
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