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Recent history demonstrates that threat has no borders, though risk does, due to national and regional differences in vulnerabilities and exposure landscapes. The difference between well and poorly managed threat is striking. Inequalities in preparing for threats as a function of their type are still apparent. Compared to more concerning electromagnetic interference threats, the impact of geomagnetic disturbance (GMD) on power grid operation is not well studied. The need for detailed research of GMD negative impacts is expected to broaden awareness. The amplitude of geomagnetically induced currents (GICs) is treated as a uniform measure of danger that can be processed by various stakeholders. Hence, methods for increasing the accuracy of GIC representation are presented in this paper. A low-entropy signal is defined and it is shown that the feature of low signal entropy can be used for increasing the accuracy of the measurement equipment. At the end, a full-system view of GMD impact on power grid operation is given.

Two major poets of the Russian Neo-Avant-Garde—Gennady Aygi and Elizaveta Mnatsakanova—created textual works that transgressed the limits of language and the borders between the arts. Each pursued their own method of the visualization and musicalization of verbal matter, yet both share a particular musical sensibility, which guarantees the integrity of the linguistic structure of their verse, despite the fragmentation and logical incoherence of its elements. The atonal (serial) musical tradition has a special significance for these experimental poetics of minimalism. Mnatsakanova, herself a musicologist, who was friends with Dmitri Shostakovich, not only used the techniques of contemporary music composition in her visual and sound poetry, but also collaborated with electronic musicians in her recorded poetry performances. Aygi experimented with language, not only crossing the boundaries between music and poetry, but also between sound and silence. For him, music was a way of expressing pre-verbal subjectivity and reproducing signs of meaning that are hidden from ordinary perception. In his poems, Aygi brought together Chuvash folk music with experimental techniques of minimalism, correlating his own work with such Soviet unofficial composers as Andrey Volkonsky and Sofia Gubaidulina. This paper will address the issues of transmutation between verbal, visual, and sound art in poetic minimalism of the Soviet-era underground.

The human pathogen Helicobacter pylori induces a strong inflammatory response in gastric mucosa manifested by the recruitment of neutrophils and macrophages to the places of infection, and by changes in epithelial integrity and function. At the molecular level, this innate immune response is essentially dependent on the activation of NF-κB transcription factors regulating the expression of chemotactic factors, e.g., IL-8. Recently, it has been demonstrated that the NF-κB signaling pathway is triggered by the bacterial heptose metabolites, which activate the host ALPK1-TIFA axis. TIFA has been suggested to promote oligomerization and activity of the E3 ubiquitin ligase TRAF6, which further stimulates TAK1-IKK signaling. Here, we demonstrate that ALPK1-dependent TIFA activation in H. pylori-infected gastric epithelial cells is followed in time by a decline in TIFA levels, and that this process is impeded by inhibitors of the proteasomal and lysosomal degradation. According to our data, TRAF2, TRAF6, TAK1 or NEMO are not required for TIFA degradation. Additionally, H. pylori promotes the interaction of TIFA with free polyubiquitin as well as with optineurin, TAX1BP1 and LAMP1, which are known protein adaptors involved in intracellular trafficking to lysosomes.

Abstract Geomagnetic disturbances (GMDs) are known to disturb power system equipment performance. The danger is associated with geomagnetically induced currents (GICs) occurring at the Earth's surface during GMD. GICs do not endanger power system operation conditions by themselves. The main challenge posed by GICs to power system states is the change in power system equipment operation conditions provoked by GIC flow. The primary avenue of blackout caused by GMDs is through power transformers. This, in turn, can impair the operation of other power system equipment such as synchronous machines. Modern powerful synchronous machines are not designed and engineered to cope with the negative impacts of GMDs. Moreover, the actual legal norms are inadequate in this case. Enhancing the grid's resiliency to such an event is highly interesting to the industry. The physical processes in synchronous machine windings triggered by GICs and limitations brought to power grid operations are described. First, the idea of the impact of GMDs on the power grid operation is described. The analysis of the impact of GMDs on synchronous machines is performed in the second section. In the end, the power system response under GMDs is studied.

The present paper sets the task to consider the issues of public financial resources consolidation in the context of disclosing tax and budgetary policy tools to minimise disparities in the sectoral structure of the Ukrainian economy. The relevance of the study is determined by the topicality of the issues of consolidation and subsequent synchronisation of the finances of public structures in order to create the necessary conditions to minimise the differences between sectors of the Ukrainian economy. In this context, it is extremely important to consider the issues of public finance consolidation through the prism of disclosing the fiscal policy tools as a means of minimising the disparities in the sectoral structure of the Ukrainian economy. The issues of budgetary policy and the economy of Ukraine are extremely important from the standpoint of assessing the correctness of the chosen course of development of Ukrainian society in general and individual sectors of the national economy in particular. The purpose of this study is to assess the real state of the country's budgetary policy in general and in the context of the consolidation of public finances as a tool to minimise these disparities in particular, as well as to consider some aspects of the current status of the Ukrainian economy. The leading approach of the study is a combination of quantitative and qualitative analysis of the matter at hand. The main results of the study were: an assessment of the level of disparities in the distribution of funds from the state budget of Ukraine for 2020; determination of the main directions for the consolidation of public finances when planning the state budget for the current financial year. Prospects for further research in this direction are determined by the importance of various aspects of the distribution of public finances in various spheres of the national economy and the need to create optimal conditions for their proper distribution. The applied value of this study lies in the assessment of the prospects for consolidating public finance as a tool to minimise the disproportions in the sectoral structure of the Ukrainian economy and the possibility of searching for and then introducing optimal ways for a qualitative resolution of this issue

The aim of the research was to develop and test Physical Education program for 20- and 21--year-old female students of Zaporizhzhia National University and Kherson State University using means of sports recreational tourism to improve their fitness. The relevance of the research is experimental approbation and further practical implementation of the aforementioned PE program featuring sports recreational tourism, into the Physical Education process for higher education. The research focuses on different aspects concerning PE, sports and students health. The results of the research have shown a significant optimization of cardiovascular system fitness level of students who attended Physical Education classes with the use of sports recreational tourism and were exposed to different types of training (from technical and tactical to special physical training). The researchers evaluated the dynamics of the integral indices of the cardiovascular system among the female students of the higher educational institutions during the course of Physical Education activities taking advantage of sports recreational tourism. It was concluded that the coherence level of the cardiovascular and respiratory systems has increased. Aerobic and mixed performance increase and cardiac activity normalization that can be seen when changing to a normotonic regulation of cardiac performance were observed.

This article examines the possibility of using paintings that reflect the image of a blind person as educational content for the training of teachers of special and inclusive school. Foreign research, as well as sociological, cultural and historical analysis of literary sources and content analysis of thematic works of painting and graphics allow us to admit the possibility and significance of using this approach in the educational process. Most of the visual arts depicting the blind reflect the current attitude of society towards them and can influence society, creating both positive and negative stereotypes through specific artistic tools. However, in the pedagogical practice of higher education, the resource of art does not find sufficient reflection. The research results can be useful for the authors of modern teaching manuals that provide training for teachers of the defectological profile.

Aim: To identify associations of anxiety symptoms (AS) and depressive symptoms (DS) with other psychosocial and lifestyle risk factors in primary care patients with arterial hypertension (AH) and/or coronary heart disease (CHD). Methods: COMETA (Clinical-epidemiOlogical prograM of studying psychosocial risk factors in cardiological practice in patiEnts with arterial hyperTension and ischemic heArt disease) is a multicenter cross-sectional study performed in 30 big cities of Russia with two to five out-patient clinics per city randomly selected and two to five general practitioners (GPs) per an out-patient clinic. Each GP included 8–10 consecutive patients with AH and/or CHD. AS and DS were assessed by the Hospital Anxiety and Depression Scale. Results: 325 GPs enrolled 2775 patients (mean age 66.7 years, 72% women) with AH (60.8%), CHD (2.6%), and AH plus CHD (36.6%). Moderate/severe (≥11 HADS) AS were found in 25.5% and DS in 16.3% patients. The strongest associations of AS and DS were revealed for high stress level (OR 5.79; 95% CI [4.18–8.03]), moderate stress level (OR 2.34; 95% CI [1.73–3.16]), low social support (OR 1.87; 95% CI [1.31–2.68]) and female gender (OR 1.78; 95% CI [1.41–2.25]). Low physical activity, unhealthy eating, unemployment and low income were also positively associated with both AS and DS (p < 0.003 for all). Conclusion: In out-patients with AH and CHD, AS and DS were strongly associated with higher levels of stress, low social support, unemployment, low family income and unhealthy lifestyle such as low physical activity, low fruit and vegetables intake and excessive salt consumption. Our findings indicate that patients with AH and CHD, who have anxiety and depressive symptoms need extra attention and monitoring in regard to stress and lifestyle risk factor control.

Apple scab caused by the ascomycete Venturia inaequalis is an economically significant disease worldwide. The annual sexual reproduction of V. inaequalis leads to high variation, changes in the population’s genetic structure and adaptations to the changing environment, including overcoming the host’s resistance. The objective of this study is to characterise and assess the genetic diversity of V. inaequalis populations in two main apple-growing regions in Latvia. In total, 143 V. inaequalis isolates were collected from Latvia, six reference strains with known virulence were obtained from other countries, and all strains were genotyped by 12 SSR markers. The SSR markers were highly variable and informative, identifying 158 alleles that ranged from two to 29 per locus. The Bayesian clustering identified three genetic lineages among the Latvian isolates that did not correlate to the geographic origin, host genotype, organ (leaves or fruits) from which the pathogen was isolated, time of collection, and type of isolation (single conidium or ascospore). The possible relatedness to virulence was detected when reference strains with known virulence were included in the analysis. Our findings correspond with previous studies demonstrating that V. inaequalis in Europe has a high genetic diversity within populations, but low diversity among the populations.

Air pollution has become a serious problem in all megacities. It is necessary to continuously monitor the state of the atmosphere, but pollution data received using fixed stations are not sufficient for an accurate assessment of the aerosol pollution level of the air. Mobility in measuring devices can significantly increase the spatiotemporal resolution of the received data. Unfortunately, the quality of readings from mobile, low-cost sensors is significantly inferior to stationary sensors. This makes it necessary to evaluate the various characteristics of monitoring systems depending on the properties of the mobile sensors used. This paper presents an approach in which the time of pollution detection is considered a random variable. To the best of our knowledge, we are the first to deduce the cumulative distribution function of the pollution detection time depending on the features of the monitoring system. The obtained distribution function makes it possible to optimize some characteristics of air pollution detection systems in a smart city.

Telehealth strategies may offer an advantage over standard institutional based interventions for improvement of cardiovascular risk in high-risk patients long-term Background: Telehealth strategies are increasingly used to support people at high cardiovascular risk long-term, but is it unclear if these interventions are effective at improving cardiovascular risk. Objective: To evaluate the effects of a telemedicine technology-based program on risk factor control and body composition in patients at high cardiovascular risk. Methods: This is a population based randomized controlled trial. 100 patients at high and very high cardiovascular risk were randomly assigned to a telemedicine technology-based program consisting of: Comprehensive counseling on risk factors delivered by a physician; biweekly remote support via phone delivered by a trained nurse during the first three months after enrollment; and a control group receiving routine care with individual single-session counseling on patients’ current risk factors without further support. The follow-up period was 1 year. Results: Mean age of participants was 59.9 ± 4.5 years, 80% were women. Weight (–0.582; p < 0.001), waist circumference (–0.429; p = 0.01), body mass index (–0.216; p < 0.001) diastolic blood pressure (–0.881; p = 0.04), total cholesterol (–0.149; p = 0.01) and LDL cholesterol (–0.123; p = 0.003) were lower in the intervention group compared to the control group after 12-month. Body fat mass was also lower (–0.352; p = 0.01) and lean mass was higher (0.92; p = 0.03) in the intervention group. Anxiety scores (–2.5; p < 0.002) and depression scores (–2.6; p < 0.001) were also lower in the intervention group. Conclusions: Among older people at high cardiovascular risk, the addition of telehealth strategies using remote support by phone calls over a period of 3 month resulted in small but significant improvements of cardiovascular risk factors, body composition, anxiety, and depression which are maintained long-term. Such telehealth strategies may offer an advantage over standard institution-based interventions.

Background: Vaccination is the most effective tool for reducing the morbidity and mortality of COVID-19. Particular interest is the development of whole-virion inactivated vaccines, since such vaccines include a complete set of viral structural proteins. One of the requirements for the whole-virion vaccines is the guarantee of complete virus inactivation while maintaining the native conformation of protective antigens. The aim of this study is to evaluate the effect of ultraviolet (UV) treatment on the morphology, antigenic and immunogenic properties of the SARS-CoV-2. Methods: SARS-CoV-2, strain "Dubrovka" (GenBank No.: MW514307.1), grown in Vero CCL81 cell culture (ATCC). Viral reproduction was monitored by real-time qRT-PCR, ELISA and virus titration in Vero cells. Virus was inactivated by treating with ultraviolet light for 5 minutes using a standard biosafety cabinet UV irradiator. Virus inactivation control was performed by three "blind" passages in Vero cells. Clarified viral material was concentrated on Amicon MWCO 100 kDa (Millipore) columns. Negatively stained with uranyl acetate viral preparation was examined by transmission electron microscopy (TEM). Mice were immunized with a UV-inactivated virus subcutaneously in two variants (5 animals per group) - with and without Freund's adjuvant, twice with an interval between immunizations of 2 weeks. The titer of virus-neutralizing antibodies in mouse sera was determined in Vero cell culture. Results: Preparation of the SARS-CoV-2 coronavirus with a titer of 7.5 lg TCID50/ml and concentration of viral RNA of 8.5 lg copies/ml was obtained in Vero cells. After UV-treatment the presence in the prepapation of SARS-CoV-2 antigen was confirmed by ELISA with a set of COVID-19 convalescent sera. The particles with coronavirus morphodiagnostic signs were imaged by TEM - rounded shape with characteristic spikes of 12-15 nm on the envelope, the diameter of the virion was 90-110 nm. Neutralizing antibodies were detected in the sera of all immunized mice, whereas in animals of the control group neutralizing antibodies were not detected. Neutralizing antibodies titer was significantly higher in animals immunized by a virus with Freund's adjuvant - on average 448, than without adjuvant - 64 (p

Helicobacter pylori infection represents a major risk factor for the development of gastric diseases and gastric cancer. The capability of H. pylori to inject the virulence factor cytotoxin-associated gene A (CagA) depends on a type IV secretion system (T4SS) encoded by the cag pathogenicity island (cagPAI). Further, infection by H. pylori activates the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in a T4SS-dependent manner but CagA-independent manner. Here we investigated the role of host cell receptors carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) and the bacterial adhesin HopQ in the activation of non-canonical NF-κB and CagA translocation into gastric epithelial cells. AGS cells express six of twelve CEACAMs found in humans. In HeLa cells, only CEACAM19 is expressed. We showed that deletion of hopQ attenuates the activation of non-canonical NF-κB only in AGS but not in HeLa cells. CagA translocation was in both cell lines affected by HopQ depletion, although to a much lesser extent in HeLa cells. Moreover, we observed a possible redundancy between the three HopQ-binding CEACAMs 1, 5 and 6 and their capacity to support non-canonical NF-κB activation. Our results illustrate that the interaction between HopQ and CEACAMs could promote the efficiency of the T4SS.

One of the adaptive strategies for the constantly changing conditions of the environment utilized in bacterial cells involves the condensation of DNA in complex with the DNA-binding protein, Dps. With the use of electron microscopy and electron tomography, we observed several morphologically different types of DNA condensation in dormant Escherichia coli cells, namely: nanocrystalline, liquid crystalline, and the folded nucleosome-like. We confirmed the presence of both Dps and DNA in all of the ordered structures using EDX analysis. The comparison of EDX spectra obtained for the three different ordered structures revealed that in nanocrystalline formation the majority of the Dps protein is tightly bound to nucleoid DNA. The dps-null cells contained only one type of condensed DNA structure, liquid crystalline, thus, differing from those with Dps. The results obtained here shed some light on the phenomenon of DNA condensation in dormant prokaryotic cells and on the general problem of developing a response to stress. We demonstrated that the population of dormant cells is structurally heterogeneous, allowing them to respond flexibly to environmental changes. It increases the ability of the whole bacterial population to survive under extreme stress conditions.

Gastric cancer is one of the leading causes of the cancer-related mortality worldwide. The etiology of this disease is complex and involves genetic predisposition and environmental factors, including Helicobacter pylori. Infection of the stomach with H. pylori leads to gastritis and gastric atrophy, which can progress stepwise to gastric cancer. Matrix metalloproteinases (MMPs) actively participate in the pathology development. The further progression of gastric cancer seems to be less dependent on bacteria but of intra-tumor cell dynamics. Bioinformatics data confirmed an important role of the extracellular matrix constituents and specific MMPs in stomach carcinoma invasion and metastasis, and revised their potential as predictors of the disease outcome. In this review, we describe, in detail, the impact of MMPs in H. pylori–associated gastritis and gastric cancer.

Multi-access edge computing has become a strategic concept of the Internet of Things. The edge computing market has reached USD several billion and is growing intensively. In the edge-computing paradigm, most of the data is processed close to, or at the edge of, the network. This greatly reduces the computation and communication load of the network core. Moreover, edge computing provides better support for user privacy. On the other hand, an increase in data processing locations will proportionately increase the attack surface. An edge node can be put out of service easily by being flooded with spoofed packets owing to limited capacities and resources. Furthermore, wireless edge nodes are quite vulnerable to energy exhaustion attacks. In this situation, traditional network security mechanisms cannot be used effectively. Therefore, a tradeoff between security and efficiency is needed. This study considered the requirements under which the use of an intrusion detection system (IDS) is justified. To the best of our knowledge, this is a first attempt to combine IDS quality, system performance degradation due to IDS operations, and workload specificity into a unified quantitative criterion. This paper is an extended version of a report published in the proceedings of the ICCSA 2020 and differs from it in many ways. In particular, this paper considers novel mathematical problems regarding the deployment strategies for an IDS and the corresponding inverse problems and provides closed-form solutions for a few previously unsolved problems.

Gastric cancer is considered one of the most common causes of cancer-related death worldwide and, thus, a major health problem. A variety of environmental factors including physical and chemical noxae, as well as pathogen infections could contribute to the development of gastric cancer. The transcription factor nuclear factor kappa B (NF-κB) and its dysregulation has a major impact on gastric carcinogenesis due to the regulation of cytokines/chemokines, growth factors, anti-apoptotic factors, cell cycle regulators, and metalloproteinases. Changes in NF-κB signaling are directed by genetic alterations in the transcription factors themselves, but also in NF-κB signaling molecules. NF-κB actively participates in the crosstalk of the cells in the tumor micromilieu with divergent effects on the heterogeneous tumor cell and immune cell populations. Thus, the benefits/consequences of therapeutic targeting of NF-κB have to be carefully evaluated. In this review, we address recent knowledge about the mechanisms and consequences of NF-κB dysregulation in gastric cancer development and therapy.

Background: The spike glycoprotein of SARS-coronavirus mediates the early events leading to infection of cells, including fusion of the viral and cellular membranes. The spike is a type I membrane glycoprotein that possesses a conserved transmembrane anchor and an unusual cysteine-rich domain that bridges the putative junction of the anchor and the cytoplasmic tail. In this study, we examined the role of these carboxyl-terminal domains in S-protein interaction with membrane. Methods: Structural model of the trimeric TM domain and adjacent fragments of ecto- and endo domains (residues 1157-1256) of the S-protein was built by homology basing on the solution structure of the SARS-coronavirus S-protein HR2 domain (pdb-code 2fxp), the structure of the transmembrane domain of HIV-1 gp41 in bicelle (5jyn), and assumption of generally coiled-coil fold of the considered domain. C-terminus of the domain was left unstructured but fully palmitoylated. Molecular dynamics simulation in heterogeneous lipid bilayer was prepared with CHARMM-GUI and performed with Gromacs during 100 ns. Results: 1. Ectodomain fragment (residues 1157-1212) demonstrates a tilt by the angle of 40-60 degrees from the axis of the TM domain (residues 1213-1237). This tilt is facilitated by glycine residues in position 1204. 2. Cholesterol molecules of the bottom layer tend to localize around protein due to interaction with palmitoyl tails while lipids in the upper layer do not show such tendency. Conclusion: Performed molecular simulations show that both palmitoylation and a large cluster of aromatic residues provide high stability of the S-protein TM domain.

Background: Histone chaperon FACT (“FAcilitates Chromatin Transcription”) is a multifunctional and conserved eukaryotic protein involved in DNA transcription, replication and repair; which can reversibly unfold nucleosomes in presence of ATP. FACT is necessary for the viability and growth of breast tumor cells meanwhile in normal cells it can be knocked out without loss of vitality. Human FACT (hFACT) is a target for promising anticancer drug curaxins, which causes FACT trapping in chromatin of cancer cells and destabilizes the nucleosome. The nucleosome-unfolding activity is an important function of hFACT in vivo; however, the mechanism of FACT-dependent nucleosome unfolding remains unknown. Methods: Here, we studied negative stained hFACT structure using single particle electron microscopy using JEOL 2100 TEM. Micrographs were captured with 25k magnification, and 4.1 Å pixel size. EM images pre-processing and single particles collection were performed in EMAN2.3, followed by 2D-particles analysis in RELION2.0. Final 2D-classes included ~70 000 single particles images. Results: Based on 2D-classess data analysis we evaluated several states of hFACT reflecting its conformational flexibility: the “closed” complex is characterized by four domains localized close to each other and forming a compact structure; “intermediate” state represented by classes with identified three domains having compact structure and more disordered fourth domain, and the “open” complex, represented by three domains forming almost linear structure. The “closed” and “open” states are present in comparable amounts and significantly outnumber the “intermediate” state. It has been shown that hFACT domains are connected through flexible linkers and SPT16 and SSRP1 dimerization domains (DDs) form the “joint”-like connection between the two subunits. In the “сlosed” conformation, the DNA-binding surface of FACT is covered by its two C-terminal and middle domains (MDs). The N-terminal domain (NTD) of SPT16 was not resolved previously, but it is the best candidate for the forth domain that is clearly visible only in the “closed” conformation of hFACT, based on its dimensions and the longest linker length. Conclusion: We propose that during conversion to the “open” complexes SPT16 NTD is moving away from the other subunits leading to formation of the first intermediate state with the NTD domain poorly resolved or not resolved, while less mobile DDs and MDs maintain more compact structure and the DNA-binding site is still protected by the CTDs. In the “open” state SPT16/SSRP1 visible MDs and DDs form almost linear structure, unmasking the DNA-binding sites and making them accessible for the interaction with a nucleosome.

Background: The severe COVID-19 pandemic started in December 2019 is caused by the SARS-CoV-2 virus. The SARS-CoV-2 virion consists of a positive-sense single-stranded RNA (ssRNA), bound with the nucleocapsid N protein and surrounded by a lipid membrane with the embedded glycoprotein S and the transmembrane proteins M and E. The structure of inactivated SARS-CoV-2 virions is crucial for the development of vaccine-induced immunity. Here we characterized the nucleic acid distribution within β-propiolactone inactivated whole-virion SARS-CoV-2 vaccine CoviVac. Methods: We used EELS to verify the presence of phosphorus (P) inside the β-propiolactone inactivated virions. Electron microscopy was performed with a JEM-2100 200kV LaB6 transmission electron microscope (JEOL, Japan) equipped with a Gatan GIF Quantum ER energy filter (Gatan, USA) operating in spectrometer mode, along with a High-Angle Annular Dark-Field (HAADF) scanning transmission electron microscopy (STEM) detector. The cooling holder model 21090 (JEOL, Japan) was operated at -182 °С to reduce the contamination effects and to enhance the specimen's stability under the electron beam. We employ a negative stain with 2% (NH4)2MoO4 rather than uranyl acetate since the Uranium O4,5 peak (edge at 96 eV) is close to the P L2,3 peak (edge at 132 eV) and interferes with the accurate background interpolation. Results: The intensity under the P peak after the background subtraction was used for STEM-EELS mapping. We observed the characteristic P signal from the inner part of the virion but not from the bare grid. The observed P signal could arise from either viral RNA or lipids of the virus membrane, and since the P signal is highly heterogeneous, it is more likely to originate from RNA. Conclusion: So far, phosphorous mapping in individual virions using EELS was done only with samples prepared using highly specialized techniques, which minimized the sample thickness, including the substrate thickness. Here, we performed elemental mapping on ordinary samples of whole viruses. All investigated virions contained P signal, but its spatial distribution and intensity differed significantly. This clearly reflects the non-even distribution of the genomic RNA, which, apparently, accompanies their inner heterogeneity, previously observed by in-situ cryo-electron tomography.

Background: We have recently developed a method to visualize the distribution of DNA in the cytoplasm of bacteria by analytical electron microscopy (EM), using the Phosphorus signal (dsDNA contains two phosphate groups per each nucleotide pair), that was detected and mapped onto the image of the cell (Danilova et al, 2020; Loiko et al, 2020). Here we applied this technique to study much smaller objects – the DNA packing inside bacteriophage heads. We studied phiEL, giant phiKZ-like bacteriophage of the Myoviridae family that infects Pseudomonas aeruginosa (Krylov et al, 2003). We have earlier demonstrated that this phage contains an ‘inner body’ inside its capsid, which is responsible for the specific DNA packing (Sokolova et al, 2014). Methods: The phage propagation was performed as described before (Sokolova et al, 2014). A 3 ul sample of purified bacteriophage phiEL was applied to the glow-discharged carbon-coated copper grid and stained with freshly prepared ammonium Molybdate 2% aquatic solution for 30 sec. Grids were loaded into Gatan cooling holder and the temperature of the specimen was kept at -180°C. EELS spectra and phosphorus elemental maps were obtained on JEOL2100 microscope, operating at 200 kV with the Gatan GIF Quantum ER spectrometer in STEM mode. Pixel size was set to 15-20 nm. STEM drift correction was applied after each 40-50 pixels. Each spectrum was obtained at a 6.0 mrad collection angle, 0.25 eV dispersion, and 132 eV energy shift. The spectra from different pixels were aligned to carbon K-edge. Results: Phosphorus mapping inside and outside the bacteriophage capsid was performed (Fig. 1). Outside the capsid, the phosphorus signal was practically absent, which corresponds to the presence of DNA only inside the capsid. The distribution of phosphorus inside the capsid was uneven: the rectangular area in the middle of the capsid contained a weak signal, while a more intense signal was detected on the periphery. This can be explained by the presence of an ‘inner body’ inside (Fig. 1C). Conclusion: Thus, our results justify the possibility of using the analytical EM technique to study the distribution of DNA by mapping Phosphorus in biological nano-objects at relatively low content of the element.

Background: Bacterial genomic DNA interacts with nucleoid-associated proteins (NAPs) and is located in a highly condensed and functional organized form in the nucleoid of the cell. The structure of the bacterial nucleoid is still awaiting its determination in high resolution. However, recent intensive research showed that condensed DNA in the bacterial nucleoid has a complex, hierarchically organized structure. Such architecture may only exist as a result of dynamic structural rearrangements, which characterize actively growing bacteria. Changes in environmental conditions are perceived by bacteria as stress. In the stationary phase caused by nutrient depletion, energy production processes become inefficient. Bacteria in the stationary phase use an energy-independent mechanism for maintaining an order to protect the DNA: the creation of stable structures, like those in inanimate nature. Cells develop into dormant forms that differ significantly in the structural organization from growing cells. Methods: Electron microscopy and synchrotron radiation diffraction studies were used to reveal distinct forms of DNA condensation in dormant E. coli cells. Results: The study made it possible to find the intracellular nanocrystalline, liquid crystalline, and folded nucleosome-like DNA structures, which were observed and described for the first time. Conclusion: The results of experiments made it possible to visualize the structures of the lower hierarchical tier of DNA compaction in the nucleoid of dormant cells. We hypothesized that the heterogeneity of bacterial cells allows for a flexible response to environmental changes and to surviving stress situations. Multiple types of DNA condensation in the same dormant E. coli cell increase the chances for rapid resumption of growth when conditions turn back to favorable.

Activation of transcription factor NF-κB is a hallmark of infection with the gastric pathogen Helicobacter pylori, associated with inflammation and carcinogenesis. Genome-wide RNAi screening revealed numerous host factors involved in H. pylori-, but not IL-1β- and TNF-α-dependent NF-κB regulation. Pathway analysis including CRISPR/Cas9-knockout and recombinant protein technology, immunofluorescence microscopy, immunoblotting, mass spectrometry, and mutant H. pylori strains identified the H. pylori metabolite D-glycero-β-D-manno-heptose 1,7-bisphosphate (βHBP) as a cagPAI type IV secretion system (T4SS)-dependent effector of NF-κB activation in infected cells. Upon pathogen-host cell contact, TIFA forms large complexes (TIFAsomes) including interacting host factors, such as TRAF2. NF-κB activation, TIFA phosphorylation, and TIFAsome formation depend on a functional ALPK1 kinase, highlighting the ALPK1-TIFA axis as a core innate immune pathway. ALPK1-TIFA-mediated NF-κB activation was independent of CagA protein translocation, indicating that CagA translocation and HBP delivery to host cells are distinct features of the pathogen’s T4SS.

Background: Data regarding anal cutaneous HPV detection among HIV-positive and HIV-negative persons largely relies on studies among men who have sex with men in limited geographical settings. Understanding the distribution, determinants, and potential human health effects of anal cutaneous HPV types among men who have sex with women (MSW) is important. Methods: Anal canal swab samples from 415 Russian MSW (384 HIV-negative and 31 HIV-positive) were tested for 43 β-HPVs and 29 γ-HPVs, using a multiplex PCR combined with Luminex technology. Results: β-HPV was detected in 24.4% and γ-HPV in 15.9% of anal samples of all Russian MSW. In total, 34 β-HPV and 19 γ-HPV types were detected, with the most commonly detected β-HPV types being 110, 22 and 124 and the most common γ-HPV types being 95, 132 and 50. For both genera, being HIV-positive at the time of testing was a significant determinant of detection (74.2% for β-HPVs and 48.4% for γ-HPVs compared to 20.1% and 12.5% in HIV-negative MSW, respectively). Conclusions: A wide spectrum and moderate prevalence of anal β-HPV and γ-HPV types was found in our MSW study sample, suggesting that routes other than penile-anal intercourse may be important in cutaneous HPV transmission. Keywords: Anal cutaneous HPV, Beta-HPV, Gamma-HPV, HIV-negative MSW, Penile-anal, HPV transmission

Background: Living organisms survive in constantly changing environmental conditions due to universal strategies of adaptation to various stresses based on structural, biochemical, and genetic rearrangements. One of adaptive strategies utilized in bacterial cells involves the protection of the nucleoid from unfavorable factors via binding of DNA to specific histone-like proteins. This strategy leads to the condensation of DNA in complexes with Dps (DNA-binding protein from starved cells), which has been discovered in starved for up to 48 hrs cells of the E. coli bacterium Methods: Electron microscopy and X-ray diffraction of synchrotron radiation studies were used to reveal distinct forms of nucleoid condensation in dormant E. coli cells that were starving for longer period – up to 7 months. Results: We have found and described not only previously detected forms of nucleoid condensation: quasi-nanocrystalline, quasi-liquid crystalline and spore-like, but also observed a new type of nucleoid condensation in dormant cells - folded nucleosome-like. Conclusion: According to the recognized concept of a bacterial population as a multicellular organism, their heterogeneity allows to respond flexibly to the environmental changes and to survive in stressful situations. Heterogeneity is the reason why we observed several types of nucleoid condensation in dormant E. coli cells. Heterogeneity of dormant cells increases the ability of the whole population to survive under various stress conditions. Results, observed here, shed a new light both on the phenomenon of nucleoid condensation in prokaryotic cells and on the general problem of developing a response to the stress.

Background: Now there are several approaches to isolate membrane proteins without detergents. Such approaches are promising as they guarantee the preservation of the lipid environment of the target proteins. One of such novel methods is based on the usage of a copolymer of styrene and maleic acid (SMA). Particles with small membrane fragments containing transmembrane proteins bounded by a polymer are called nanodisks (SMALPs). Methods: We chose HEAG2 with affine 1d4 tag at the C-terminus as an object of interest. Channels were expressed in COS-1 eukaryotic cell line (African green monkey kidney fibroblast-like cell line). The potassium channels were integrated into SMALPs during the solubilization and then purified via affinity chromatography. The embedding of the channel into the particles with SMA was confirmed by immunoblotting. Dynamic light scattering was used to confirm the formation of SMALPs with channel protein. Obtained samples were subjected to negative stain electron microscopy. Results: We have succeeded to extract voltage-gated potassium channels from the membrane fractions directly. The hydrodynamic diameter of the formed particles was 15.5 nm. The analysis of EM images also confirmed the formation of nanoparticles. Conclusion: The technique for solubilizing and purifying ion channels from eukaryotic cells using SMA allows to make three-dimensional reconstruction of the particles.

Background: Phage U47 belongs to the Luz24-virus genus of the Podoviridae family. Due to the effective mechanism of host metabolism suppression and an ability to penetrate bacterial biofilms Luz24-like Pseudomonas aeruginosa phages prospective for phage therapy applications. The relatively long tail of U47 makes it a promising model for structural studies of podoviruses. Yet, the structural information concerning adsorption complex of podoviruses, which is crucial for understanding of the infection process, is limited. Methods: For the purification of the U47 phage, we used ultracentrifugation in a cesium gradient and further dialysis against buffer with low osmotic pressure. U47 solution was mixed 10:1 with 0.05% Tween 20. 3ul of the sample were applied onto the hydrophilized holey carbon support film (Quantifoil 1.2/1.3). A total of 6500 movies were collected using cryo-TEM Krios (Thermo-Fisher, USA) at acceleration voltage 300kV, pixel size 1.15Å, flux approx. 100 e/A2s. Motion correction and CTF estimation was performed using Warp, particles were picked and processed in CryoSPARC and Relion 3.0. In spite of the absence of highly similar homologues molecular model of this protein was built with Modeller using HHpred for homology search. As templates surwed the structures of the major capsid proteins from bacteriophages Hk97 (pdb: 1OHG) and phi812K1-420 (pdb: 5LII). Structural model was fitted into the obtained cryo-EM density map. Results: We have obtained the icosahedral reconstruction of the U47 phage capsid with a resolution of 4.5 ~ 6Å and the reconstruction of its tail with C6 symmetry. The elongated tail structure can be divided into 2-3 structural compartments (similar to the T7 phage; tail fibrils are visible that are attached to the distal tail protein; the tail possesses a distal spike, located parallel to the long axis of the tail, similar to that of phages P22 and SF6. Also, the globular domain is clearly visible. Conclusion: Here, we have, for the first time, reconstructed the capsid and tail of the P.aeruginosa U47 phage and demonstrated that it possesses all the structural features of the Luz-24-like family. Further investigations should shed light to the specific adsorption complex of this phage.

Uropathogenic Escherichia coli (UPEC) is a causative agent in the vast majority of urinary tract infections (UTIs), including cystitis and pyelonephritis, and infectious complications, which may result in acute renal failure in healthy individuals as well as in renal transplant patients. UPEC expresses a multitude of virulence factors to break the inertia of the mucosal barrier. In response to the breach by UPEC into the normally sterile urinary tract, host inflammatory responses are triggered leading to cytokine production, neutrophil influx, and the exfoliation of infected bladder epithelial cells. Several signaling pathways activated during UPEC infection, including the pathways known to activate the innate immune response, interact with calcium-dependent signaling pathways. Some UPEC isolates, however, might possess strategies to delay or suppress the activation of components of the innate host response in the urinary tract. Studies published in the recent past provide new information regarding how virulence factors of uropathogenic E. coli are involved in activation of the innate host response. Despite numerous host defense mechanisms, UPEC can persist within the urinary tract and may serve as a reservoir for recurrent infections and serious complications. Presentation of the molecular details of these events is essential for development of successful strategies for prevention of human UTIs and urological complications associated with UTIs.

Airway epithelial cells play a major role in initiating inflammation in response to bacterial pathogens. S. aureus is an important pathogen associated with activation of diverse types of infection characterized by inflammation dominated by polymorphonuclear leukocytes. This bacterium frequently causes lung infection, which is attributed to virulence factors. Many of virulence determinants associated with S. aureus-mediated lung infection have been known for several years. In this paper, we discuss recent advances in our understanding of known virulence factors implicated in pneumonia. We anticipate that better understanding of novel functions of known virulence factors could open the way to regulate inflammatory reactions of the epithelium and to develop effective strategies to treat S. aureus-induced airway diseases.