Determining triple half-twist of optical Möbius strips in electromagnetic fields with a non-planar structure.

Polarization ellipses in a nonparaxial field form twisted strips when traced along closed contours around a circular polarization singularity line. We found an analytical expression for the twist number of the strip when the contour is coplanar with the polarization ellipse in its center. Necessary and sufficient conditions for strips having one or three half-twists are found. A set of five parameters of electromagnetic field at the polarization singularity point is found which definitely determines the value of the twist number of the strip.

General dynamics of the URT microbiome and microbial signs of recovery in COVID-19 patients.

COVID-19 is caused by an airborne virus, SARS-CoV-2. The upper respiratory tract (URT) is, therefore, the first system to endure the attack. Inhabited by an assemblage of microbial communities, a healthy URT wards off the invasion. However, once invaded, it becomes destabilised, which could be crucial to the establishment and progression of the infection. We examined 696 URT samples collected from 285 COVID-19 patients at three time-points throughout their hospital stay and 100 URT samples from 100 healthy controls. We used 16S ribosomal RNA sequencing to evaluate the abundance of various bacterial taxa, α-diversity, and ß-diversity of the URT microbiome. Ordinary least squares regression was used to establish associations between the variables, with age, sex, and antibiotics as covariates. The URT microbiome in the COVID-19 patients was distinctively different from that of healthy controls. In COVID-19 patients, the abundance of 16 genera was significantly reduced. A total of 47 genera were specific to patients, whereas only 2 were unique to controls. The URT samples collected at admission differed more from the control than from the samples collected at later stages of treatment. The following four genera originally depleted in the patients grew significantly by the end of treatment: Fusobacterium, Haemophilus, Neisseria, and Stenotrophomonas. Our findings strongly suggest that SARS-CoV-2 caused significant changes in the URT microbiome, including the emergence of numerous atypical taxa. These findings may indicate increased instability of the URT microbiome in COVID-19 patients. In the course of the treatment, the microbial composition of the URT of COVID-19 patients tended toward that of controls. These microbial changes may be interpreted as markers of recovery.

Cognitive impairment in long-living adults: a genome-wide association study, polygenic risk score model and molecular modeling of the APOE protein.

Background: Cognitive impairment is an irreversible, aging-associated condition that robs people of their independence. The purpose of this study was to investigate possible causes of this condition and propose preventive options. Methods: We assessed cognitive status in long-living adults aged 90+ (n = 2,559) and performed a genome wide association study using two sets of variables: Mini-Mental State Examination scores as a continuous variable (linear regression) and cognitive status as a binary variable (> 24, no cognitive impairment; <10, impairment) (logistic regression). Results: Both variations yielded the same polymorphisms, including a well-known marker of dementia, rs429358in the APOE gene. Molecular dynamics simulations showed that this polymorphism leads to changes in the structure of alpha helices and the mobility of the lipid-binding domain in the APOE protein. Conclusion: These changes, along with higher LDL and total cholesterol levels, could be the mechanism underlying the development of cognitive impairment in older adults. However, this polymorphism is not the only determining factor in cognitive impairment. The polygenic risk score model included 45 polymorphisms (ROC AUC 69%), further confirming the multifactorial nature of this condition. Our findings, particularly the results of PRS modeling, could contribute to the development of early detection strategies for predisposition to cognitive impairment in older adults.

Features of the use of ladder myoplasty of a gunshot wound to the laryngopharynx: Case report.

INTRODUCTION AND IMPORTANCE: The laryngopharynx wound is considered to be one of the most severe wounds of neck both in war and in peace, as it may cause life threatening changes in the whole body (asphyxia, bleeding, shock). Important aspects of surgical treatment are to ensure full breathing, acceptable ways of feeding, and the use of reliable wound closure techniques aimed to prevent digestive tract failure and to maintain the framework and aerostasis of the laryngotracheal region. CASE PRESENTATION: A case of unilateral multiple wounds of the laryngopharynx was described in the article. The features of diagnostics, surgical treatment and conservative therapy in the postoperative period with this injury were presented. The wounded man was urgently operated. During surgery the pharynx was mobilized. The metal fragment was removed. The wound of the pharynx was sutured with a two-row suture. The next stage of the surgical treatment was myoplasty. In the case of the patient, the purpose of myoplasty was additional sealing of the pharyngeal suture and myoplasty of the thyroid cartilage injury zone for the purpose of aerostasis. Because of the size of the wounds and their anatomical localization, we used the mobilized lower edge of the Musculus sternocleidomastoideus for myoplasty and proposed the method of ladder myoplasty developed by us. CLINICAL DISCUSSION: In myoplasty method the following criteria must be followed: the muscle flap must be of sufficient length and width, so as not to cause excessive tension in the myoplasty area; the flap must be thick enough to avoid necrosis that may cause subsequent infectious complications; when taking the flap, the most sparing operative access should be used to avoid functional and anatomical disorders; the volume of the taken muscle flap must not lead to functional and anatomical disorders. CONCLUSION: The proposed method of ladder myoplasty using Musculus sternocleidomastoideus is unique, and proves its high efficiency in unilateral multiple laryngopharyngeal injuries, and can be recommended for wide clinical implementation in such clinical situations.

Indices of polarization Möbius strips surrounding lines of circular polarization in nonparaxial optical fields.

Detailed analysis of polarization ellipse strips constructed on small circular contours surrounding a single polarization singularity line of an electromagnetic field is carried out. It is shown that the strips formed by major and minor axes of polarization ellipses are nonorientable Möbius strips with opposite directions of twist. Explicit analytical expressions relating the direction of the strip twist to the orientation of its construction contour and the parameters of the electromagnetic field at the polarization singularity point are found.

Transformation of spin and orbital angular momentum in second-harmonic generation process by the near-surface layer of isotropic nonlinear medium.

We investigate the conversion between orbital and spin components of the angular momentum of light beams in the second-harmonic generation process from the near-surface layer of the nonlinear isotropic medium without spatial dispersion at oblique incidence of the elliptically polarized fundamental beam. The conservation of the projection of both spin and orbital angular momenta onto the normal to the surface of the medium during the transformation of the incident wave into a reflected double frequency wave has been demonstrated.

[Review of the possible impact of 100% juices on nutritional quality, risk of obesity and type 2 diabetes mellitus].

Studies show that fruit juices are a source of macro- and micronutrients. Despite the fact that modern technologies for the industrial processing of fruits into juice are aimed at preserving the bioactive compounds of the original raw materials, juices are the subject of controversy due to the presence of free sugars and less dietary fiber than in fresh fruits. The purpose of the work was to systematize the available studies on the effect of 100% juices on nutrition quality, obesity and type 2 diabetes mellitus. Material and methods. Systematic search in PubMed, Google Scholar, eLIBRARY databases in accordance with the inclusion criteria: the study examined 100% fruit or vegetable juices, the article was in Russian or English in a peer-reviewed journal, the subjects (in the case of clinical studies) were people aged 1 to 18 years and older. 98 sources were analyzed based on the title of the article, of which 35 did not relate to juices. 63 sources were analyzed based on their abstracts, of which 28 were included in the main study. Results. According to the results of the literature analysis, it follows that moderate consumption of 100% juices not only does not have negative effects on human health, but, on the contrary improve the health of the organism. In particular, its intake helps lower blood pressure and the content of highly sensitive C-reactive protein, thereby reducing the risk of cardiovascular diseases. Juices enrich the daily diet due to the macro- and micronutrients they contain, which improves the quality of nutrition in general. Researches prove that there is no correlation between moderate juice consumption and type 2 diabetes onset. The glycemic index of the juices is low or medium, which distinguishes them from standard soft drinks containing sugar. The consumption of juices (100-500 ml/day) does not increase the risk of obesity in adults and children. Conclusion. Negative effects, such as weight gain and an increased risk of diabetic diseases, can only be observed with excessive consumption of juices.

PDSTP Is the First Drug in Class to Treat Coronavirus Infection.

The results of a comprehensive study are presented on the development and creation of an original small PDSTP molecule, able to prevent the SARS-CoV-2 coronavirus infection from binding to the host cell. The PDSTP molecule was designed to electrostatically interact with heparan sulfate proteoglycans on the cell surface, and coronaviruses, particularly SARS-CoV-2, use this mechanism as the first stage of interaction with the cell. By blocking this process, it is possible to stop the life cycle of the virus, thus leading to its death. The drug candidate PDSTP, with its unique mechanism of action, is characterized by a very low toxicity and a high safety profile and demonstrates good efficacy in animal experiments.

Creation of a Supercomputer Simulation of a Society with Different Types of Active Agents and Its Approbation.

This article continues a series of works devoted to the creation of large agent-based models, built as an artificial society, and the development of software for their implementation-the MÖBIUS design system for scalable agent-based models. The basic core of the system is a demographic model that simulates the natural movement of the population. A new stage in the development of the work discussed in this article was the creation on the basis of this core of an agent-based model of Russia, which includes families as agents of a new type, hierarchically connected with human agents. In addition, objects of a new type were introduced into the model-projects that provide for the creation in an artificial environment of analogues of complex control actions aimed at stimulating fertility. Developed on the basis of simulating the reaction of individual families to the introduced regional support measures, the model makes it possible to track their impact on key demographic indicators. The agent-based model of Russia was tested on data for a long retrospective period using the example of the launch of maternal capital programs and showed good agreement with official statistics.

Bacterial Lysate Complex Administered Intranasally Suppresses Inflammation in an In Vivo Model of Aseptic Lymphadenitis.

The effect of a bacterial lysate complex IRS 19 on local and systemic manifestations of inflammation was studied in a rat model of aseptic lymphadenitis. Injection of λ-carrageenan into the cervical lymph node via surgical approach caused an increase in the thickness of the capsule, disturbances in histoarchitecture, the appearance of necrosis foci, histiocytosis of subcapsular and cerebral sinuses in the lymph node, as well as an increase in the level of TNFα in the blood serum and the number of circulating leukocytes and neutrophils. Course intranasal administration of bacterial lysate complex in this model dose-dependently reduced the level of these markers of the systemic inflammatory response and the severity of microstructural disorders in the affected lymph nodes. Thus, bacterial lysate complex after intranasal administration produces a systemic anti-inflammatory effect that goes beyond the respiratory tract.

Interconversion between OAM and SAM in five-wave mixing process in medium with the fourth-order optical susceptibility.

We investigate the interconversion between spin components of the angular momentum (SAM) and orbital components of the angular momentum (OAM) of collinear elliptically polarized monochromatic fundamental beams with frequencies ω1 and ω2 in the five-wave mixing process in homogeneous isotropic nonracemic mixtures of chiral molecules with nonlinear fourth-order susceptibility. Fundamental beams have helicoidal wavefronts and arbitrary radial distributions of intensity. The discovered non-conservation of the total SAM and OAM projections on the direction of propagation of the interacting waves during the generation of radiation at the frequency 3ω1 - ω2 compensate each other, ensuring the conservation of the total angular momentum projection. A straightforward classical and quantum interpretation of the results is given.

Transformation of spin and orbital angular momentum in second-harmonic generation process at oblique incidence of light from the surface of an isotropic medium with spatial dispersion of quadratic nonlinearity.

We discuss key features of the conversion of spin and orbital angular momentum of electromagnetic waves in the process of second-harmonic generation from the surface of the isotropic medium at oblique incidence. Conservation of the projections of spin and orbital parts of angular momentum of interacting waves onto the normal to the surface is shown for an arbitrary case of polarization and mode structure of the incident light beam.

[The study of tryptophan metabolite concentrations in blood serum and fecal extracts from obese children]. / Izuchenie soderzhaniia metabolitov obmena triptofana v syvorotke krovi i kalovykh ékstraktakh u detei s ozhireniem.

We found that changes in the concentrations of tryptophan metabolites in the blood serum and in the intestinal contents are one of the mechanisms for the formation of metabolic coupling in the system "macroorganism-intestinal microbiota", which undergoes significant changes in the development of obesity. Although blood kynurenine remained basically unchanged in obese children we found an increase in some of its serum metabolites: anthranilic, kynurenic and xanthurenic acids. It is noteworthy that in the analysis of fecal matter in obese children, revealed a 2-fold increase in the level of kynurenine while the concentration of kynurenine pathway metabolites corresponded to the level of the group of healthy children. This may indicate the metabolic activation of the microbiota associated with the intestinal mucosa. This is also supported by the absence of statistically significant differences in the concentration of indole in healthy children and in obese children in fecal analyses, and a significant increase in the concentration of indole-3-lactate and indole-3-acetate in the blood serum of obese children.

Three-dimensional structure of polarization singularities of a light field near a dielectric spherical nanoparticle.

We numerically study the structure of polarization singularity lines in a near-field of the sub-wavelength dielectric particle when it is irradiated by a monochromatic elliptically polarized plane wave. For the various values of the ellipticity degree of the incident radiation, we trace the CT and LT-lines on which the polarization ellipse turns into a circle or a line, respectively. The continuous variation of the isotropy parameters of the singularities is visualized along the lines. The main rules of CT and LT-lines deformation, emergence, and vanishing are revealed.

[Biological value of fruits and berries of Russian production].

Fruits and berries are the most important sources of a wide range of biologically active substances, including vitamin C, carotenoids, flavonoids, anthocyanins. In order to replenish and update data on the content of food and biologically active substances in the tables of the chemical composition of food products, a study of the content of mono- and disaccharides, dietary fiber was carried out; vitamins C, B1, B2 and E, minerals and trace elements; flavonoids (in terms of rutin), anthocyanins; organic and hydroxycinnamic acids, stilbenoids in various varieties of 16 fruit and berry crops. Material and methods. The material for the study was the fruits of promising varieties and selected forms of pome fruit (apple, pear), stone fruit (cherry, plum, apricot), berry (garden strawberry, raspberry, black currant, red currant, gooseberry), non-traditional crops (actinidia, honeysuckle, cornelian cherry, viburnum, sea buckthorn, rosehip) - a total of 208 samples grown at the I.V. Michurin Federal Scientific Center. The B vitamins were determined by the fluorometric method, and vitamin E, organic and hydroxycinnamic acids, carbohydrates, and stilbenoids were determined by HPLC. The amount of anthocyanin pigments was determined by pH differential spectrophotometry, dietary fiber - by enzymatic-gravimetric method, flavonoids - spectrophotometrically. Results and discussion. The main carbohydrate of apricot is sucrose, black currants, cherries, raspberries and honeysuckle contain mainly fructose and glucose. Raspberries and currants are high in fiber. Comparison of the obtained data on the content of vitamins B1, B2, E, flavonoids and anthocyanins in the studied population of varieties in comparison with the published data of tables of the chemical composition of food products in the USA and Russia was carried out. By the content of vitamin C in descending order, the fruits are arranged in a row: black currant > sea buckthorn > honeysuckle > strawberry > red currant > viburnum > gooseberry > raspberry > apple. Berries, making a significant contribution to providing the body with vitamin C, are not an essential source of vitamins B and E. The inclusion of 100 g of fresh fruit in the diet provides about 10% of the recommended dietary intake for potassium (apricot, gooseberry, cherry and black currant), magnesium (apple, cherry, strawberry) and dietary fiber. Honeysuckle and black currant are high in anthocyanins; consumption of 100 g of these berries will ensure adequate intake of these micronutrients. Some varieties of strawberries, apples and pears are rich in hydroxycinnamic acids. The data obtained can be used to refine the indicators in the existing tables of the chemical composition of food products. Conclusion. The obtained data on the composition of fruit and berry products will make it possible to more correctly calculate the nutritional value of rations using questionnaire-survey methods. Combined analysis of the composition of biologically active substances in berries and fruits makes it possible to more reasonably make the choice of a particular product in the dietary correction of the ration of healthy and sick people.

Correlation of synovial caspase-3 concentration and the photodynamic effectiveness in osteoarthritis treatment.

BACKGROUND: The present study focuses on investigation of Intra-articular PDT mechanisms for OA treatment. Also, a search for determination of the most effective dose of chlorin e6 (Ce6) for anti-inflammatory PDT of OA was carried out. METHODS: The study was carried out on laboratory animals (11 Chinchilla rabbits, 1 year, 2.5 kg) with a gonarthritis model of post-traumatic OA. According to the instructions for using Photoditazin (Ce6 based PS) for PDT of human oncological and non-oncological diseases, the recommended dose is 0.7-1.2 mg/kg. For studies on rabbits, taking into account the conversion coefficient (3.2), the PS doses of 2.4, 3.2 and 6.4 mg/kg were selected. Fluorescence spectra were measured intra-articular before and after PDT using spectrometer with fiber-optic probe. The intrajoint PDT was carried out using a laser (662 ± 10 nm) and a fiber-optic catheter with a cylindrical diffuser inside a sapphire needle for a uniform distribution of the laser radiation. The immunohistochemical study was carried out by staining the samples with caspase-3. RESULTS: Histological and immunohistochemical analysis showed that the best PS dose for intravenous administration for PDT of rabbit gonarthritis is 3.2 mg/kg. The PS concentration directly in the synovial tissue was 0.5 mg/kg, and this was enough to achieve the most positive results to reduce the caspase-3 level. CONCLUSION: The caspase-3 level correlates well with other signs of inflammation in the synovial membrane (edema, etc.). Therefore, to assess the PDT effectiveness in the treatment of gonarthritis accompanied by synovitis, it is sufficient to analyze only for caspase-3. The efficacy of PDT with Ce6 showed that 3.2 mg/kg PS dose (1 mg/kg for a human) is the most effective.

[Nutrient value of fruit in promising strawberry varieties].

One of the current areas in research of fruit and berry crops is the study of their nutritional value and micronutrient composition. Valuable chemical composition of the strawberry determines a wide spectrum of its utilization not only as fresh fruit, but also as a raw material for food industry. Breeding requirements for contemporary strawberry varieties together with yield, large-fruit, important taste and dietary qualities of fruit provide for higher content of biologic active substances. The aim of the research was an integrated assessment of strawberry fruit for content of nutrients and bioactive compounds, as well as mineral elements, and its antioxidant activity. Material and methods. The objects of investigation were berries of 5 strawberry varieties bred in the I.V. Michurin Scientific Centre (Lakomaya, Prazdnichnaya, Privlekatelnaya, Urozhaynaya CGL, Feyerverk) and 9 foreign varieties (Vima Zanta, Dukat, Zefir, Kama, Maryshka, Red Gauntlet, Festivalnaya romashka, Honey, Elsanta) which are promising for cultivation in the Black Soil Region of Russia. The content of soluble solids was determined by the refractometric method, sugars - by Bertrand's method, pectins - by the volumetric method, anthocyanins - by pH-differential spectrophotometry. Total content of antioxidants was defined by amperometric method with recalculation per quercetin. Determination of vitamin B1 was carried out using the fluorometric thiochrome method, vitamin B2 - by fluorometric titration with riboflavin-binding apoprotein after acid-enzymatic hydrolysis, ascorbic acid, vitamin E (tocopherols), niacin, organic and hydroxycinnamic acids - by HPLC, flavonols - spectrophotometrically, minerals and trace elements - by atomic absorption method. Results and discussion. A significant variation in the chemical composition indices depending on the varietal characteristics was found. Strawberry fruit accumulated 8.5-12.0% soluble solids, 5.9-8.7% sugars, 1.5-2.1% of fibre, 0.78-1.12% pectin substances, 0.89-1.45% organic acid; 100 g contain 33.5-48.2 mg vitamin C, 18.3-108.5 mg anthocyanins, 0.024-0.041 mg vitamin B1, 0.012-0.029 mg vitamin B2, 0.10-0.26 mg niacin, 0.26-0.60 mg TE vitamin E, 102-270 mg potassium, 0.15-0.95 mg iron; total antioxidant activity ranged within 180.8-350.0 mg/100 g. High level of anthocyan accumulation (over 80.0 mg/100 g) was observed in Privlekatelnaya, Lakomaya and Feyerverk strawberry varieties. Urozhaynaya CGL, Privlekatelnaya and Lakomaya varieties were characterized by dessert taste. According to the results of the studies Privlekatelnaya variety stood out because of the high complex accumulation of vitamin C, anthocyanins, and high total antioxidant activity. These varieties are recommended for both fresh use and for freezing, as well as for production of functional foods. Conclusion. The obtained data are of interest for further inclusion in the Tables of the chemical composition of Russian food products.

IMPACT OF AG NANOPARTICLES ON MICROORGANISMS, CAUSATIVE AGENTS OF PURULENT-INFLAMMATORY PROCESSES.

Determination of Ag nanoparticles impact on microorganisms causative agents of purulent-inflammatory processes was carried out and it was stated that the greatest significance of growth inhibition zone was found in Staphylococcus aureus and Streptococcus pyogenes with sample length from 1 to 6 mm and Escherichia coli with 5-6 mm sample length. The investigated strains in an amount 104 - 106 CFU/ml were sensitive to Аg nanoparticles activity, but at concentration 108 CFU/ml and more all strains were found persistent to samples of various length. The ability to form biofilms with planktonic cells of microorganisms under Ag nanoparticles activity sufficiently reduced from 3.4 (Candida albicans) to 5.5 (Klebsiella pneumonia) in investigated strains. The disorganization of daily biofilms was found in determining of Ag nanoparticles impact on formed biofilms of microorganisms.

Combined treatment of nonresectable cholangiocarcinoma complicated by obstructive jaundice.

BACKGROUND: The five-year survival rate for successful surgical treatment of cholangiocellular cancer is only 20-40%, and in the case of an unresectable tumor, the life expectancy does not usually exceed 6 months. Survival decreases with the presence of jaundice, due to the spread of the tumor process along the bile ducts, leading to their obstruction. We report outcomes of patients with nonresectable bile duct carcinoma complicated by obstructive jaundice treated with Photodynamic Therapy (PDT). METHODS: Combined diagnosis and treatment included percutaneous cholangiostomy, intraductal video fluorescence diagnostics, photodynamic therapy, and bile duct stenting. All patients were treated at the Sechenov University Oncology Center in Moscow. The results of treatment of 33 patients have been presented. The intraductal diagnosis of malignant bile duct lesions was performed after cholangiostomy using the endovideofluorescence module for minimally invasive surgery and endoscopy. With the use of this method, it is the first time in Russia that it has become possible to obtain a videofluorescent image of the tumor and to determine the high level of photosensitizer accumulation in all cholangiocarcinoma patients. The preparations Photolon, Radachlorin, and Photosens were employed as photosensitizers (PS). Intraductal photodynamic therapy was used to achieve the antitumor effect. Laser power density was about 200 mW/cm2. RESULTS: We present initial results, improved the diagnostic possibilities in this difficult localization of carcinoma, and demonstrated the feasibility of prolongation of life without significant deterioration of its quality. The average survival time in the treatment group is 9.5 months. CONCLUSION: The treatment of patients with nonresectable cholangiocarcinoma with Photodynamic Therapy should be an available option. In this context, the additional use of intraductal endovideofluorescence diagnostics is a highly specific technique that allows reliable detection of the photosensitizer accumulation predominantly by the tumor tissue and appears promising. As shown by our experience, flourescent localization followed by Photodynamic Therapy, enabled us to improve diagnostic techniques and treat the tumor with improved outcome.

Functional Analysis of Coilin in Virus Resistance and Stress Tolerance of Potato Solanum tuberosum using CRISPR-Cas9 Editing.

The role of the nuclear protein coilin in the mechanisms of resistance of potato Solanum tuberosum cultivar Chicago to biotic and abiotic stresses was studied using the CRISPR-Cas9 technology. For the coilin gene editing, a complex consisting of the Cas9 endonuclease and a short guide RNA was immobilized on gold or chitosan microparticles and delivered into apical meristem cells by bioballistics or vacuum infiltration methods, respectively. Editing at least one allele of the coilin gene considerably increased the resistance of the edited lines to infection with the potato virus Y and their tolerance to salt and osmotic stress.