[Predictors of thromboembolic complications in patients with severe SARS-CoV-2 coronavirus infection].

AIM: To identify predictors of the development of thromboembolic complications (TECs) in patients with severe SARS-CoV-2 coronavirus infection. MATERIALS AND METHODS: A single-center observational retrospective study included 1634 patients with a confirmed diagnosis of SARS-CoV-2 coronavirus infection. The patients were divided into 2 groups depending on the availability of the feasibility study. The criterion for inclusion of patients in the main group was the presence of venous feasibility studies in 127 patients (group I), the comparison group consisted of 1507 patients in whom the course of COVID-19 was not complicated by the development of feasibility studies (group II). RESULTS: When performing computed tomography of the chest organs, it was revealed that patients with a feasibility study had a higher percentage of lung tissue damage than patients in the comparison group: 55% [37.5; 67.5] and 37.5% [25.0; 47.5], respectively (p<0.001). The average values of C-reactive protein in I patients group were 129 [60.1; 211] ng/l, which was significantly higher than in II patients group - 41.0 [12.2; 97.6] ng/l (p<0.001), interleukin-6 - 176 [52.9; 471] pg/ml and 39.4 [11.0; 107] pg/ml (p<0.001), respectively. A one-factor regression analysis proved a significant contribution of comorbid pathology to the development of feasibility studies in patients with COVID-19. The presence of three nosologies at the same time: arterial hypertension, coronary heart disease (CHD) and chronic kidney disease increased the probability of a feasibility study by 4.81 times (odds ratio 4.8117, 95% confidence interval 3.2064-7.2207), in patients with arterial hypertension, CHD, chronic kidney disease and type 2 diabetes - by 5.63 times (odds ratio 5.6321, 95% confidence interval 3.1870-9.9531). CONCLUSION: The presence of severe comorbid pathology significantly increased the risk of developing a feasibility study in patients with COVID-19. The most significant predictors of the development of feasibility studies in patients with severe SARS-CoV-2 coronavirus infection. They are: CHD, arterial hypertension and type 2 diabetes.

[Indocyanine green in liver tumor resection]. / Primenenie ICG na etapakh planirovaniya i realizatsii rezektsii pecheni po povodu opukholei.

Primary liver cancer and colorectal cancer liver metastases are among the leading causes of cancer-related mortality worldwide. Surgery is one of the main methods of treatment to achieve the best results in overall and recurrence-free survival. The main objectives in this surgery are preoperative planning, assessment of functional viability of liver parenchyma and total resection with low complication rate. Post-resection liver failure is one of the most formidable and often fatal complication following functional failure of liver remnant. Thus, preoperative assessment of liver functional reserves is a necessary step for adequate selection of patients and safe surgery. Passive liver tests, such as biochemical parameters or clinical scales, do not accurately reflect the actual functional component of liver parenchyma. The most accurate method is dynamic quantitative test of liver, such as indocyanine green clearance. The authors discuss the practical aspects of preoperative assessment of liver functional reserves using indocyanine green, as well as the concept and technical foundations of fluorescent imaging in hepatobiliary surgery.

The Search for Single-Domain Antibodies Interacting with the Receptor-Binding Domain of SARS-CoV-2 Surface Protein.

We performed a search for nanoantibodies that specifically interact with the receptor-binding domain (RBD) of the SARS-CoV-2 surface protein. The specificity of single-domain antibodies from the blood sera of a llama immunized with RBD of SARS-CoV-2 surface protein S (variant B.1.1.7 (Alpha)) was analyzed by ELISA. Recombinant trimers of the SARS-CoV-2 spike protein were used as antigens. In this work, a set of single-domain antibodies was obtained that specifically bind to the RBD of the SARS-CoV-2 virus.

The Rarity of Metastasis to the Spleen - a Phenomenon with an Unknown Mechanism.

The review analyses the frequency of malignant tumors metastasizing to the spleen. The facts are presented of a higher frequency of metastasis to the spleen in the presence of multiple metastases to other organs and the extreme rarity of isolated metastases to the spleen. Despite the rarity of spleen metastases, their frequency varies depending on the nosological form of the malignancy. The data about clinical manifestations of spleen metastases and positive effects of splenectomy in these cases are presented. The hypotheses explaining the rarity of metastases to the spleen are analyzed. Emphasis is placed on the multiple immune functions of the spleen, including the development of immunogenesis and tolerance, and the possible role of these processes in inhibiting the development of spleen metastases. However, to date, there is no complete understanding of the mechanisms of spleen metastasis inhibition. The spleen is an area where antimetastatic microenvironment is naturally formed. Understanding of the mechanisms inhibiting the development of metastases in the spleen and underlying the failure of this function in cases where metastases do occur could arm oncologists with a new strategy to prevent metastasis to any organ. Targeted research in this field is required.

Video or text? Education through a social media website in hypertension.

Background: Currently, several studies are available on the effective use of the Instagram social media platform to conduct training projects for CVD patients. The aim of this study was to determine the most effective methods (text or video) of informing people about the primary prevention of hypertension using a social media website. Materials and methods: A total of 125 participants were randomly selected and assigned to one of the four training groups depending on the training mode, i.e. text posts (4000 characters) - Group 1, video clips (5 min) - Group 2, text followed by video - Group 3 and video followed by text - Group 4. Before and after training, respondents in all four groups completed the Heart Disease Knowledge Questionnaire (HDKQ). Results: The total number of people who listened to and read the materials of the online school was 2108 people. Before training, the number of correct responses for 29 HDKQ statements was 18.4 ± 5.1, after training it increased to 21.9 ± 3.9 (CI, 21; 22.7) (p < 0.0001). The post-hoc analysis showed that after training the participants in Group 4 had more correct responses than the respondents in Group 3, 2, 1 i.e. Δ = 5.2, Δ = 1.5, Δ = 0.3, respectively. The respondents from Group 3 gave the lowest number of correct responses in other groups. Conclusions: The most effective method of informing people about the primary prevention of hypertension using a social media website corresponded to the following sequence: a video clip followed by a text post.

Immunogenicity of the DNA/Protein Combined Vaccine against COVID-19.

During the COVID-19 pandemic, the development of prophylactic vaccines, including those based on new platforms, became highly relevant. One such platform is the creation of vaccines combining DNA and protein components in one construct. For the creation of DNA vaccine, we chose the full-length spike protein (S) of the SARS-CoV-2 virus and used the recombinant receptor-binding domain (RBD) of the S protein produced in CHO-K1 cells as a protein component. The immunogenicity of the developed combined vaccine and its individual components was compared and the contribution of each component to the induction of the immune response was analyzed. The combined DNA/protein vaccine possesses the advantages of both underlying approaches and is capable of inducing both humoral (similar to subunit vaccines) and cellular (similar to DNA vaccines) immunity.

Immunogenic Properties of the DNA Construct Encoding the Receptor-Binding Domain of the SARS-CoV-2 Spike Protein.

The development of preventive vaccines became the first order task in the COVID-19 pandemic caused by SARS-CoV-2. This paper reports the construction of the pVAX-RBD plasmid containing the Receptor-Binding Domain (RBD) of the S protein and a unique signal sequence 176 which promotes target protein secretion into the extracellular space thereby increasing the efficiency of humoral immune response activation. A polyglucine-spermidine conjugate (PGS) was used to deliver pVAX-RBD into the cells. The comparative immunogenicity study of the naked pVAX-RBD and pVAX-RBD enclosed in the PGS envelope showed that the latter was more efficient in inducing an immune response in the immunized mice. In particular, RBD-specific antibody titers were shown in ELISA to be no higher than 1 : 1000 in the animals from the pVAX-RBD group and 1 : 42 000, in the pVAX-RBD-PGS group. The pVAX-RBD‒PGS construct effectively induced cellular immune response. Using ELISpot, it has been demonstrated that splenocytes obtained from the immunized animals effectively produced INF-γ in response to stimulation with the S protein-derived peptide pool. The results suggest that the polyglucine-spermidine conjugate-enveloped pVAX-RBD construct may be considered as a promising DNA vaccine against COVID-19.

[Immunogenic Properties of the DNA Construct Encoding the Receptor-Binding Domain of the SARS-CoV-2 Spike Protein].

The development of preventive vaccines became the first order task in the COVID-19 pandemic caused by SARS-CoV-2. This paper reports the construction of the pVAX-RBD plasmid containing the Receptor-Binding Domain (RBD) of the S protein and a unique signal sequence 176 which promotes target protein secretion into the extracellular space thereby increasing the efficiency of humoral immune response activation. A polyglucine-spermidine conjugate (PGS) was used to deliver pVAX-RBD into the cells. The comparative immunogenicity study of the naked pVAX-RBD and pVAX-RBD enclosed in the PGS envelope showed that the latter was more efficient in inducing an immune response in the immunized mice. In particular, RBD-specific antibody titers were shown in ELISA to be no higher than 1 : 1000 in the animals from the pVAX-RBD group and 1 : 42000, in the pVAX-RBD-PGS group. The pVAX-RBD-PGS construct effectively induced cellular immune response. Using ELISpot, it has been demonstrated that splenocytes obtained from the immunized animals effectively produced INF-y in response to stimulation with the S protein-derived peptide pool. The results suggest that the polyglucine-spermidine conjugate-enveloped pVAX-RBD construct may be considered as a promising DNA vaccine against COVID-19.

Orbital Complexity in Intrinsic Magnetic Topological Insulators MnBi_{4}Te_{7} and MnBi_{6}Te_{10}.

Using angle-resolved photoelectron spectroscopy (ARPES), we investigate the surface electronic structure of the magnetic van der Waals compounds MnBi_{4}Te_{7} and MnBi_{6}Te_{10}, the n=1 and 2 members of a modular (Bi_{2}Te_{3})_{n}(MnBi_{2}Te_{4}) series, which have attracted recent interest as intrinsic magnetic topological insulators. Combining circular dichroic, spin-resolved and photon-energy-dependent ARPES measurements with calculations based on density functional theory, we unveil complex momentum-dependent orbital and spin textures in the surface electronic structure and disentangle topological from trivial surface bands. We find that the Dirac-cone dispersion of the topologial surface state is strongly perturbed by hybridization with valence-band states for Bi_{2}Te_{3}-terminated surfaces but remains preserved for MnBi_{2}Te_{4}-terminated surfaces. Our results firmly establish the topologically nontrivial nature of these magnetic van der Waals materials and indicate that the possibility of realizing a quantized anomalous Hall conductivity depends on surface termination.

Prototype of a DNA Vaccine against Marburg Virus.

The preparation and study of the biological properties of the pVAKS-GPVM DNA immunogen containing a gene encoding Marburgvirus glycoprotein are described. The specificity of blood serum antibodies of guinea pigs immunized with DNA immunogen was analyzed by ELISA. Inactivated viral preparation, recombinant glycoprotein (GP) obtained in the prokaryotic system and virus-like particles based on the recombinant vesicular stomatitis virus exhibiting Marburgvirus GP were used as the antigens. The neutralizing activity of antibodies of immunized animals was tested in vitro using a pseudovirus system. It was demonstrated that the developed immunogen administered to guinea pigs induced the production of specific antibodies that neutralize virus-like particles and Marburgvirus in cultured Vero cells.

Prediction and observation of an antiferromagnetic topological insulator.

Magnetic topological insulators are narrow-gap semiconductor materials that combine non-trivial band topology and magnetic order1. Unlike their nonmagnetic counterparts, magnetic topological insulators may have some of the surfaces gapped, which enables a number of exotic phenomena that have potential applications in spintronics1, such as the quantum anomalous Hall effect2 and chiral Majorana fermions3. So far, magnetic topological insulators have only been created by means of doping nonmagnetic topological insulators with 3d transition-metal elements; however, such an approach leads to strongly inhomogeneous magnetic4 and electronic5 properties of these materials, restricting the observation of important effects to very low temperatures2,3. An intrinsic magnetic topological insulator-a stoichiometric well ordered magnetic compound-could be an ideal solution to these problems, but no such material has been observed so far. Here we predict by ab initio calculations and further confirm using various experimental techniques the realization of an antiferromagnetic topological insulator in the layered van der Waals compound MnBi2Te4. The antiferromagnetic ordering  that MnBi2Te4  shows makes it invariant with respect to the combination of the time-reversal and primitive-lattice translation symmetries, giving rise to a ℤ2 topological classification; ℤ2 = 1 for MnBi2Te4, confirming its topologically nontrivial nature. Our experiments indicate that the symmetry-breaking (0001) surface of MnBi2Te4 exhibits a large bandgap in the topological surface state. We expect this property to eventually enable the observation of a number of fundamental phenomena, among them quantized magnetoelectric coupling6-8 and axion electrodynamics9,10. Other exotic phenomena could become accessible at much higher temperatures than those reached so far, such as the quantum anomalous Hall effect2 and chiral Majorana fermions3.

[Characteristics of free fatty acid metabolism in pathogenesis of obesity: current view].

Obesity is a chronic disease that turns up one of the main healthcare problems in the majority of industrialized countries. In modern literature, free fatty acid (FFA) metabolism disturbances are thought to play one of the key roles in the pathogenesis of obesity. This review accumulates and summarizes basic facts on FFA normal metabolism and currently known concepts explaining the relation between FFA metabolism disturbances and pathogenesis of obesity and associated complications. Ectopic fat recruitment (i.e., in nonadipose tissues) appears to be a key feature of metabolic disturbances in obesity. It was the finding, that has led to the believe that an imbalance in fatty acid trafficking away from adipose tissue towards non-adipose tissues is a primary cause for the development of metabolic alterations in obese subjects. Recently FFA trafficking within non-adipose tissues cells (particularly towards storage in the form of triglycerides and oxidation) has considerably more important significance in the pathogenesis of obesity. After that FFA has established to be important signaling molecules, interacting with specific receptors (that are localized in different tissues) and by this way influence on body metabolism. Failure of these influences also appears to be important factor of obesity pathogenesis. Thus, FFA metabolism play an important role in obesity pathogenesis. This influence is caused by both FFA trafficking and oxidation disturbances in adipose and non-adipose tissues and direct interaction of FFA with specific receptors in different tissues.

Chemically driven surface effects in polar intermetallic topological insulators A3Bi.

Surface electronic spectra, surface and bulk properties as well as the underlying chemical bonding characteristics in topological insulators with complex bonding patterns are considered for the example of cubic, polar intermetallics KNa2Bi, K3Bi and Rb3Bi (with the general formula A3Bi, A - alkali metal). Chemical bonding in A3Bi has a delocalized, polar character as elucidated by the Bader charge analysis in bulk and at the surface, by real-space bonding indicators and by the maximally localized-Wannier-function technique. We underpin emergent surface features in the electronic spectra that are driven by chemical bonding. The organization of these trivial and topological surface states is juxtaposed with the trends in the Bader charges at the surface and surface contributions to the on-site matrix elements of the ab initio Hamiltonian in the localized basis. The surface states are essentially affected by a large positive or negative on-site contribution induced near the vacuum boundary, where the sign of the contribution depends on the surface termination. Based on our findings, the experimentally observed surface features in the related Na3Bi compound can be correctly interpreted. The listed aspects distinguish the title compounds from the HgX (X - chalcogen) series with the same fingerprint bulk-band dispersion near the Fermi level and similar symmetries, but with covalent bonding character. Surface effects investigated for A3Bi also can be expected for a wide range of compounds of various topological classes with a similar bonding type, and will define their surface reactivity.

[A new approach in the compression therapy of postoperative scars]. / Novyi podkhod v kompressionnoi terapii posleoperatsionnykh rubtsov.

The aim of the study was to evaluate the effectiveness of compression therapy with a prolonged plaster of Contractubex in the formation of skin scarring in children after surgery. MATERIAL AND METHODS: In a prospective open-label randomized trial, 109 patients aged 5.3±2.1 years after surgery: boys - 73, girls - 36. Patients were divided into 2 groups: in the main group (54 children) the application of the prolonged plaster Contractubex was performed; in the control group (55 patients) - dynamic observation. The scar deformation was assessed according to the Vancouver scale for 10, 30 and 90 postoperative days. RESULTS: 94.4% patients had good compliance; in 2 (3.7%) - satisfactory; in 1 (1.9%) - unsatisfactory compliance. In our study, the formation of hypertrophic scars in the main group was significantly less frequent than in the control group (1 and 8 patients, respectively, χ2=4.241, p=0.042). CONCLUSION: Thus, the use of the prolonged plaster Contractubex in the near and distant period a good cosmetic and functional result in the formation of a postoperative scar was provided.

[The complications of intestinal stoma in children]. / Oslozhneniia kishechnykh stom u detei.

AIM: To investigate the complications of intestinal stoma in children and to develop measures for decrease of their incidence. MATERIAL AND METHODS: The study included 152 children with congenital and acquired gastrointestinal pathology requiring surgical treatment with the imposition of intestinal stoma. Atresia of intestinal tube was observed in 28 (18.4%) children, meconium ileus - in 10 (6.6%) cases, Hirschsprung's disease - in 11 (7.2%)cases, anorectal malformations - in 39 (25.7%) cases, multiple malformations - in 11 (7.2%) patients, necrotic enterocolitis - in 56 (36.8%) patients, other reasons - in 7 (4.6%) cases. The average age of patients was 12,3±7,2 days. There were 93 (61.2%) boys and 59 (38.8%) girls. Ileostomy, ileocolostomy and colostomy were made in 37 (24.3%), 46 (30.3%) and 69 (45.4%) cases respectively. Time of intestinal stoma function was 18-217 days. RESULTS: Early complications were dehiscence in the area of stoma in 4 (2.6%) children, evagination in 7 (4.6%) patients, marginal necrosis of stoma in 2 (1.3%) cases, retraction of stomy into abdominal cavity in 1 (0.6%) child and abdominal skin maceration in 8 (5.2%) patients. Remote complications included dermatitis around stomy in 35 (23.1%) children, stenosis of stoma in 9 (5.9%) cases, evagination of stoma in 12 (7.9%) patients. Also, 5 patients were unable to use the colostomy bag due to vicious overlaying of intestinal stoma. Using the colostomy bags «Coloplast¼ and skin care products around the stoma significantly reduced (p<0.01) the number of complications at inpatient stage of treatment. CONCLUSION: Successful function of stoma depends on not only technical aspects but also obligatory care performance with timely correction of complications.

J_{eff} Description of the Honeycomb Mott Insulator α-RuCl_{3}.

Novel ground states might be realized in honeycomb lattices with strong spin-orbit coupling. Here we study the electronic structure of α-RuCl_{3}, in which the Ru ions are in a d^{5} configuration and form a honeycomb lattice, by angle-resolved photoemission, x-ray photoemission, and electron energy loss spectroscopy supported by density functional theory and multiplet calculations. We find that α-RuCl_{3} is a Mott insulator with significant spin-orbit coupling, whose low energy electronic structure is naturally mapped onto J_{eff} states. This makes α-RuCl_{3} a promising candidate for the realization of Kitaev physics. Relevant electronic parameters such as the Hubbard energy U, the crystal field splitting 10 Dq, and the charge transfer energy Δ are evaluated.

Comparative Evaluation of ß-Catenin and E-Cadherin Expression in Liquid Aspiration Biopsy Specimens of Thyroid Nodules.

We compared the results of gene molecular and immunocytochemical studies of ß-catenin and E-cadherin in different variants of nodular thyroid disease (nodular colloid goiter, follicular thyroid adenocarcinoma, papillary thyroid cancer) and revealed changes of the function of the E-cadherin/ß-catenin complex leading to switching from adhesion function of ß-catenin in nodular colloid goiter to predominantly transcriptional activity in papillary carcinoma. The results confirm the important role of disturbances in E-cadherin-ß-catenin interactions in the mechanisms of malignant transformation of follicular epithelium.

Mirror-symmetry protected non-TRIM surface state in the weak topological insulator Bi2TeI.

Strong topological insulators (TIs) support topological surfaces states on any crystal surface. In contrast, a weak, time-reversal-symmetry-driven TI with at least one non-zero v1, v2, v3 ℤ2 index should host spin-locked topological surface states on the surfaces that are not parallel to the crystal plane with Miller indices (v1 v2 v3). On the other hand, mirror symmetry can protect an even number of topological states on the surfaces that are perpendicular to a mirror plane. Various symmetries in a bulk material with a band inversion can independently preordain distinct crystal planes for realization of topological states. Here we demonstrate the first instance of coexistence of both phenomena in the weak 3D TI Bi2TeI which (v1 v2 v3) surface hosts a gapless spin-split surface state protected by the crystal mirror-symmetry. The observed topological state has an even number of crossing points in (r-M)the directions of the 2D Brillouin zone due to a non-TRIM bulk-band inversion. Our findings shed light on hitherto uncharted features of the electronic structure of weak topological insulators and open up new vistas for applications of these materials in spintronics.

[ß-Catenin: Structure, Function and Role in Malignant Transformation of Epithelial Cells].

The article presents the data on the structure and mechanisms of ß-catenin functioning. The basic aspects of the role of ß-catenin in malignant transformation have been studied at various tumors. Primary structure of ß-catenin allows it to interact with many factors and ligands, including transcription factors, α-catenin, cadherin, Axin, Rho family GTPases, Bcl9 et al. This interaction is the base for ß-catenin's intracellular multi-functioning. The review presents data on the participation of ß-catenin in the mechanisms of adhesion, regulation of RNA metabolism, formation contacts with the cytoskeleton and its role in the canonical Wnt signaling pathway, marked examples pro-inflammatory and anti-inflammatory effects of ß-catenin. The ß-catenin involvement in malignant transformation and progression of certain tumors is not in doubt. The data on the changes in ß-catenin expression in the given examples of colon cancer, prostate cancer, different forms of thyroid cancer and hepatocellular carcinoma are presented with the prospects of its use as a marker and a predictor of malignant transformation. Continued research in this area will not only make use of ß-catenin as a potential predictor of malignant tumors, but also to develop approaches to targeted therapy.

[The severity of menopausal symptoms and cardiovascular risk in women].

Menopause is a crucial time in the life of any women. Perhaps the severity of menopausal symptoms defines further state of female health. The aim of the study is to assess changes of cardiovascular system during perimenopause and the connection between this changes and severity of menopausal symptoms. The data of 155 premenopausal women without coronary heart disease were analyzed. To assess women hormonal state follicle stimulating hormone was measured. The severity of menopausal symptoms was evaluated with the help of Kupperman questionnaire form in Uvarova modification. All women were divided into two groups according to follicle stimulating hormone. Women with follicle stimulating hormone higher 30 MU/l were classified as postmenopausal. It was shown that groups of pre - and postmenopausal women significantly differ in age, progesterone, follicle stimulating hormone level, and SCORE. The severity of menopausal symptoms was the same in studied groups. Regression analysis revealed that severity of menopausal symptoms depended on systolic blood pressure, follicle stimulating hormone level, progesterone level. The link between cardiovascular risk (SCORE) and follicle stimulating hormone, NO2, ApoА1, and severity of menopausal symptoms was found.