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Hysteresis response of epitaxially grown graphene nanoribbons devices on semi-insulating 4H-SiC in the armchair and zigzag directions is evaluated and studied. The influence of the orientation of fabrication and dimensions of graphene nanoribbons on the hysteresis effect reveals the metallic and semiconducting nature graphene nanoribbons. The hysteresis response of armchair based graphene nanoribbon side gate and top gated devices implies the influence of gate field electric strength and the contribution of surface traps, adsorbents, and initial defects on graphene as the primary sources of hysteresis. Additionally, passivation with AlOx and top gate modulation decreased the hysteresis and improved the current-voltage characteristics.

BACKGROUND: Currently, no study has investigated on the role of ghrelin in the reinforcing system and emotional behavior. Previously, we examined the properties of GHSR1A antagonist [D-Lys3]-GHRP-6 to reduce negative emotional states caused by stress. AIM: To study the involvement of a new peptide antagonist of the GHSR1A receptor agrelax in the control of emotionalexploratory behavior and anxiety in rats. MATERIALS AND METHODS: Experiments were performed on 42 male Wistar rats. The behavior of rats was observed; agrelax 1 g/mL (or water) with a volume of 20 L (10 l in each nostril) was administered intranasally. A battery of behavioral tests was used: an elevated plus maze, an open field, a marble test, an intruderresident test, and an anxiety-phobic state assessment (FS). RESULTS: In the elevated plus maze test, the time spent in the light arm and the number of hangings from the open arm increased in the test animals compared with animals that did not receive the drug (p 0.05). After the administration of agrelax, the number of balloons buried and the number of elevations supported by the wall of the chamber in the marble test decreased compared with that in animals that did not receive the drug (p 0.05). In the open field, agrelax-infected rats showed a decrease in the number of sniffs (p 0.01). In the FS test after the agrelax administration, the time of descent from the platform decreased compared with the control (p 0.05). In the intruderresident test, individual behavior (p 0.01) and protective behavior (p 0.05) decreased after agrelax administration. CONCLUSION: A new peptide antagonist of the GHSR1A receptor agrelax is involved in the control of emotionalexploratory behavior in rats. Agrelax reduced anxiety levels and exploratory activity. The results provide grounds for the development of new approaches to the treatment of phobic spectrum disorders using drugs that modulate ghrelin regulation.

BACKGROUND: Exposure to acute or chronic stress contributes to the occurrence of various disorders of the central nervous system, psycho-emotional sphere, as well as increases the risks of development of various forms of addiction. AIM: The aim of the study is analyze the influence of maternal deprivation on voluntary alcohol consumption in adolescents and to determine the degree of the signs of compulsive behavior in experimental animals. MATERIALS AND METHODS: Thirty male Wistar rats were taken in the research. A maternal deprivation model was carried out from day 2 to day 12 of the postnatal period (MD). Compulsivity (compulsive tendency) was evaluated in the ball burial test. Voluntary alcoholization with 10% ethyl alcohol solution in a two-bottle test was employed. Level of progesterone in blood plasma was determined by enzyme- immune analyses. RESULTS: Changes in the level of progesterone in blood plasma in MD and control group of animals were detected. In the test of two bottles 10% of ethanol solution presented on days 2 and 3, statistically significant differences in consumption were determined in contrast to the control group. In the test of balloon diapering, MD group of animals showed a statistically proved significant increase in compulsiveness both before the beginning of voluntary alcoholization and on day 3 from the start. CONCLUSIONS: The increase in compulsivity and voluntary ethanol consumption was significantly higher in the MD group, that is comparable to the increased level in blood plasma progesterone samples.

There is a constant need to create methods for improving the quality indicators of information processing. In most practical cases, the ranges of target variables and predictors are formed under the influence of external and internal factors. Phenomena such as concept drift cause the model to lose its completeness and accuracy over time. The purpose of the work is to improve the processing data samples quality based on multi-level models for classification and regression problems. A two-level data processing architecture is proposed. At the lower level, the analysis of incoming information flows and sequences takes place, and the classification or regression tasks are solved. At the upper level, the samples are divided into segments, the current data properties in the subsamples are determined, and the most suitable lower-level models are assigned according to the achieved qualitative indicators. A formal description of the two-level architecture is given. In order to improve the quality indicators for classification and regression solving problems, a data sample preliminary processing is carried out, the model’s qualitative indicators are calculated, and classifiers with the best results are determined. The proposed solution makes it possible to implement constantly learning data processing systems. It is aimed at reducing the time spent on retraining models in case of data properties transformation. Experimental studies were carried out on several datasets. Numerical experiments have shown that the proposed solution makes it possible to improve the quality processing indicators. The model can be considered as an improvement of ensemble methods for processing information flows. Training a single classifier, rather than a group of complex classification models, makes it possible to reduce computational costs.

BACKGROUND: The search for new drugs potentially effective in stopping the development of pathological addictions is an urgent task of experimental psychopharmacology. AIM: To examine the participation of brain monoaminergic systems in the mechanisms of the blocking effect of SB-408124 on the self-stimulation of the lateral hypothalamus activated with the psychostimulant -phenylisopropylamine (PIPA) treatment. MATERIALS AND METHODS: Male Wistar rats pre-administered with psychostimulant (PIPA, 1 mg/kg intraperitoneally) were unilaterally injected with an orexin antagonist SB-408124 (1 g in 1 L) into the central nucleus of the amygdala or the bed nucleus of the stria terminalis (BNST). High-performance liquid chromatography with electrochemical detection was used to determine the levels of monoamines and their metabolites: norepinephrine (NA), dopamine (DA), serotonin (5-HT), dioxyphenylacetic (DOPAC), homovaniline (HVA), and 5-hydroxyindolacetic (5-HIAA) acids on the left and right sides of the prefrontal cortex, hippocampus, striatum, and olfactory tubercle. RESULTS: Under the action of PIPA, microinjections of SB-408124 into the right central nucleus of the amygdala induced the following effects: prefrontal cortex, an increase in the levels of HVA and 5-HT on the right side and 5-HIAA on the left; hippocampus, bilateral increase in the levels of NA and HVA and 5-HT on the right; striatum, bilateral increase in the level of DA and the left-sided increase in HVA, 5-HT, and 5-HIAA. Microinjections into the left central nucleus of the amygdala caused a right-sided decrease in NA levels, an increase in 5-HT levels, and a left-sided decrease in DA and DOPAC levels in the striatum and a left-sided increase in HVA level in the olfactory tubercle. Microinjections into the right BNST caused a left-sided decrease in the levels of NA and DA in the prefrontal cortex, bilateral decrease in DOPAC levels, a right-sided increase in 5-HT levels, and a left-sided increase in 5-HIAA levels in the striatum; and a left-sided increase in HVA levels in the olfactory tubercle. Microinjections into the left BNST caused increased 5-HT levels in the left striatum and decreased DOPAC and 5-HIAA levels in the left olfactory tubercle. CONCLUSIONS: Right-sided microinjections cause a greater number of changes in monoamine metabolism than left-sided ones. The introduction of SB-408124 into the right structures of the enlarged amygdala increases 5-HIAA levels in the left striatum, whereas microinjections in BNST lead to increased 5-HT levels in the ipsilateral striatum and in the contralateral in the central nucleus of the amygdala

Body composition reflects the dynamic processes in a child’s development. The recommended restrictive diets for patients with advanced chronic kidney disease (CKD) contribute to a high risk of sarcopenic muscle wasting as diagnosed by bioimpedancemetry.The aim of the study. To assess BMI and body composition in children with CKD, to identify features of body composition in patients with different BMI Z-score values.Materials and methods. The physical development of 110 children with CKD of different stages was assessed. Patients were divided into two clusters: Group 1 (92 children) with BMI from 10.95 to 21.5 kg/m2, BMI Z-score did not exceed +2.0 (without obesity); Group 2 (18 children) – BMI from 24.11 to 37.2 kg/m2, Z-score BMI – more than +2.0 (obese). All underwent bioimpedancemetry, the proportion of fat and active cell mass was assessed. The comparison was carried out by nonparametric statistics methods.Results. Changes in body composition were revealed: children without obesity had severe protein-energy deficiency in 7 cases (7.6 %). The difference in the proportion of fat mass in children of different groups, Me [Q1; Q3]: Group 1 – 18.00 % [14.00; 22.00], Group 2 – 35.00 % [21.98; 41.00], (Mann – Whitney U-test: U = 279.5, p = 0.00001). In Group 1, the active cell mass was 53.50 % [51.00; 56.00], in Group 2 – 41.50 % [39.00; 47.00] (U = 174.5, p = 0.000001), there were no significant differences in other parameters of bioimpedancemetry.Conclusions. The proportion of active cell mass is lower in overweight children, with a significant predominance of the proportion of fat mass, which indicates the depletion of protein reserves due to their redistribution and possible insufficient alimentary intake in advanced stages of CKD.

This research aims to improve quality indicators in solving classification and regression problems based on the adaptive selection of various machine learning models on separate data samples from local segments. The proposed method combines different models and machine learning algorithms on individual subsamples in regression and classification problems based on calculating qualitative indicators and selecting the best models on local sample segments. Detecting data changes and time sequences makes it possible to form samples where the data have different properties (for example, variance, sample fraction, data span, and others). Data segmentation is used to search for trend changes in an algorithm for points in a time series and to provide analytical information. The experiment performance used actual data samples and, as a result, obtained experimental values of the loss function for various classifiers on individual segments and the entire sample. In terms of practical novelty, it is possible to use the obtained results to increase quality indicators in classification and regression problem solutions while developing models and machine learning methods. The proposed method makes it possible to increase classification quality indicators (F-measure, Accuracy, AUC) and forecasting (RMSE) by 1%–8% on average due to segmentation and the assignment of models with the best performance in individual segments. Doi: 10.28991/ESJ-2023-07-03-03 Full Text: PDF

A design project for calibrating holes in parts, e.g. in hobs, discs, gear wheels, un-der conditions of ultrasonic effects application is suggested. Formula, providing a way for varying the value of the ultrasonic pulse pbr in a part is derived. It allows ensuring the required accuracy of the hole at lower pressures in the contact zone of a mandrel with the treated surface and, as a consequence, to reduce the magnitude of the traction force of the calibration process, which is especially important in hole-making operations for parts subjected to heat treatment.

Background. The main problem in the patient selection for cardiac resynchronization therapy (CRT) is the lack of unified approaches to the definition of mechanical dyssynchrony (MD) and selection criteria.Objective. To reveal the dependence of the criteria of dyssynchrony in patients on the method and point of stimulation and to reveal the correlation of these data with the width of the QRS complex and the percentage of global two-dimensional longitudinal deformation.Design and methods. The study involved 12 patients with drug-compensated CHF of class II-IV, LVEF< 35 % and a QRS duration >130 ms, having CRT indications. All patients were intraoperatively injected with a retrograde transaortically guided electrode. During stimulation of each point (88 points), transesophageal Echo-KG (PE Echo-KG) was performed. TomTec and Philips Qlab 3DQ Advanced software was used for data analysis.Results. The segmental excursion and myocardial contractility differed significantly depending on the stimulation point. A moderate inverse correlation was found between ExcAvg, LVEF and QRS duration. There were a direct correlation of the SDI-16 and the QRS duration was shown, and an inverse correlation of SDI-16 with ExcAvg and LVEF. 2D longitudinal global strain was inversely correlated with the EF.Conclusion. The technique is useful for regional LV myocardial contractility assessment and patient selection and comparison of alternative approaches to LV pacing to improve response to CRT.

Spectral lines in the optical spectra of atoms, molecules, and other quantum systems are characterized by a range of frequencies ω or a range of wavelengths λ=2πc/ω, where c is the speed of light. Such a frequency or wavelength range is called the width of the spectral lines (linewidth). It is influenced by many specific factors. Thermal motion of the molecules results in broadening of the lines as a result of the Doppler effect (thermal broadening) and by their collisions (pressure broadening). The electric fields of neighboring molecules lead to Stark broadening. The linewidth to be considered here is the so-called parametric broadening (PB) of spectral lines in the optical spectrum. PB can be considered the fundamental type of broadening of the electronic vibrational–rotational (rovibronic) transitions in a molecule, which is the direct manifestation of the basic concept of the collapse of a wavefunction that is postulated by the Copenhagen interpretation of quantum mechanics. Thus, that concept appears to be not only valid but is also useful for predicting physically observable phenomena.

State policy in the field of road safety is aimed at protecting the life, health and property of citizens and protecting the interests of society and the state by preventing road accidents and reducing the severity of their consequences. In searching for mechanisms to implement these goals, the legislator to the challenges in the field of road safety, which contribute to road accidents. The article examines the trends in criminal law responses to driving under the influence of alcohol. The criteria for criminalisation of an act under article 2641 of the Criminal Code of the Russian Federation are disclosed. The author focuses on the disclosure of public danger of the act, drawing attention to the existing shortcomings in law enforcement, as well as assesses the effectiveness of the application of Art. 2641 of the Criminal Code in solving the issues of road safety. Based on the results of the study, the author concludes that there is an effective potential of the criminal law prohibition of driving a vehicle while under the influence of alcohol by a person who has been subjected to administrative penalty or has a criminal record. The author proposes the introduction of amendments to the criminal law legislation, aimed at strengthening the measures of criminal law impact on persons operating a vehicle in a state of intoxication.

One of the unresolved problems on the way to improving the pharmacotherapy of CNS diseases is the development and creation of technologies that allow drugs to cross the blood-brain barrier (BBB). The review discusses modern methods of drug delivery to the CNS. The advantages and disadvantages of the main pharmacological strategies for directly overcoming the BBB and an alternative to this are shown. New methods of drug delivery to the brain with damage (physical, chemical, etc.) and without disruption of the blood-brain barrier structure (small molecules, cell-mediated transport, stem cells) are considered. The prospects for the use of artificial nanosized drug transporters are discussed. An alternative strategy of pharmacological action on the CNS structures (intranasal route) is shown to be promising. Possible mechanisms of action of pharmacological agents on CNS structures bypassing the BBB are considered.

BACKGROUND: Literature data indicated that ghrelin may be a stress neuropeptide in some animals, including Danio rerio. AIM: The aim of the study was to measure the levels of ghrelin in Danio rerio brain (forebrain, midbrain, and hindbrain) after predator exposure (predator stress test) and administration of ghrelin and oxytocin antagonists to assess the role of ghrelin in stress response. MATERIALS AND METHODS: The study used 68 Danio rerio, one predator of Cichlasoma nicaraguensis. Ghrelin levels were measured by enzyme-linked immunosorbent assay. The following pharmacological agents were used: 1) ghrelin antagonist hexapeptide [D-Lys3]-GHRP-6 (Tocris, UK); 2) recombinant peptide analog of ghrelin agrelax with a molecular weight of 3.5 kDa, developed at the IEM (both compounds in equal dosages of 0.333 mg/L); corticoliberin (Tocris) at a dosage of 0.4 mg/L; and oxytocin (Gedeon Richter, Hungary) at a dosage of 3.8 L (0.005 IU/L) per 50 mL of aquarium water (0.019 IU/L). RESULTS: In the control group, ghrelin level was determined only in the hindbrain, and ghrelin levels in the forebrain and midbrain were 4 pg/mg of total protein. Contact with a predator led to a significant increase in ghrelin levels in the forebrain and midbrain, but not in the hindbrain. Thus, in fish forebrain, ghrelin levels increased to 966 12 pg/mg of protein, which is almost a 250-fold increase in the indicator compared with the level in intact animals. In the presence of agrelax, [D-Lys3]-GHRP-6, and oxytocin, ghrelin levels in the forebrain and midbrain of stressed fish decreased approximately equally to 88 3, 97 1, and 115 1 pg/mg protein, respectively. CONCLUSION: Thus, stress exposure (contact with a predator) significantly increases ghrelin levels in the forebrain and midbrain but decreases in the hindbrain. Stress-protective peptides (oxytocin, [D-Lys3]-GHRP-6, and agrelax) decreased ghrelin levels in the forebrain and midbrain, and to a lesser extent, in the hindbrain when exposed to stress.

This review provides information on the features, incidence, pathogenetic mechanism, possibilities of conservative, laser and surgical treatment of glaucoma in pregnant women. The purpose of this literature review is to study the features of managing patients with glaucoma during pregnancy. Glaucoma is a large group of eye diseases characterized by a gradual development of visual impairments and atrophy of the optic nerve. The pathology is most common among the population over 40 years old, but due to the advancement of reproductive technologies, the availability of diagnostic methods, as well as high clinical awareness, the frequency of ophthalmologists managing glaucoma in pregnant women increases. Elevated intraocular pressure in pregnant women is becoming more common and, therefore, is an urgent problem. There is a trend towards an increase in the number of pregnant women who experienced elevated intraocular pressure for the first time. Previously identified pathology in childhood or secondary glaucoma due to previous ophthalmic diseases or severe somatic pathology is a special category of patients. Such patients are encountered regularly and require close supervision by both an ophthalmologist and a gynecologist. The evidence base for antiglaucoma drugs is small; there are clinical experiments on animals, which results do not always carry over to humans, and retrospective studies. The doctor's arsenal presently includes a number of drugs that have possible side effects for the fetus, as well as laser and surgical treatment. There is no standard treatment, so each case should be considered individually with an understanding of the physiology, mechanism of action of the drugs and their possible effects. Therefore, glaucoma during pregnancy and lactation is a serious medical problem, and its solution depends on interdisciplinary medical approach.

International audience; A simple and effective preparation of solution-processed chalcogenide thermoelectric materials is described. First, PbTe, PbSe, and SnSe were prepared by gram-scale colloidal synthesis relying on the reaction between metal acetates and diphenyl dichalcogenides in hexadecylamine solvent. The resultant phase-pure chalcogenides consist of highly crystalline and defect- free particles with distinct cubic-, tetrapod-, and rod-like morphologies. The powdered PbTe, PbSe, and SnSe products were subjected to densification by spark plasma sintering (SPS), affording dense pellets of the respective chalcogenides. Scanning electron microscopy shows that the SPS-derived pellets exhibit fine nano-/micro-structures dictated by the original morphology of the key constituting particles, while the powder X-ray diffraction and electron microscopy analyses confirm that the SPS-derived pellets are phase-pure materials, preserving the structure of the colloidal synthesis products. The resultant solution-processed PbTe, PbSe, and SnSe exhibit low thermal conductivity, which might be due to the enhanced phonon scattering developed over fine microstructures. For undoped n-type PbTe and p-type SnSe samples, an expected moderate thermoelectric performance is achieved. In contrast, an outstanding figure-of-merit of 0.73 at 673 K was achieved for undoped n-type PbSe outperforming, the majority of the optimized PbSe-based thermoelectric materials. Overall, our findings facilitate the design of efficient solution-processed chalcogenide thermoelectrics.

The article presents dynamic methods for assessing the performance of a tractor unit, substantiates the dependence of transient processes of a tractor in an unsteady mode of operation. The performance of tractor units provides for an assessment of the ability to perform the specified functions that meet the requirements of regulatory and technical documentation. It is proposed to evaluate the performance of the tractor units when its technical condition changes by the magnitude and direction of the deviation of the center of gravity of the real transient process from the reference model. Express methods for diagnosing the steering and braking systems of a tractor are presented. The proposed express method of diagnosing the steering of the tractor allows you to carry out diagnostics with the least amount of time without the presence of a special platform. For diagnosing brake systems of tractors, a new indicator - the growth rate of deceleration - has been proposed as a diagnostic tool

The paper analyzes the influence of the geometric parameters of the semi-trailer unit on the stability of its movement. A mathematical model of the dynamics of the cultivator unit under the influence of disturbing forces is developed. The analysis of research results shows that in the process of movement, the wheeled semi-trailer unit is subjected to transverse forces, which arise as a result of the unevenness of the traction resistance of the side and rear beams. The main vector and the main moment cause the unit to deviate from the rectilinear movement. The differential equations obtained in the work make it possible to determine the values of the lead angles, their components, and the speed at which the lead of the unit will be the smallest. Based on the dependence of the angle of departure of the unit on the disturbing forces and speed of movement, the optimal location of the side bars of the semi-trailer unit on the tractor frame was found.

The article presents analysis of the methods and means of evaluating of the traction properties tractor. In the previous researches, it was propose to evaluate of the traction properties tractor on their supporting-coupling properties without taking into account the stochastic modes of exploitation and modes of operation. Experimental methods of definitions the traction of tractor require conducting a large number of experiments. Therefore, it is necessary to carry out an analysis of the methods and the means of improving the results of the definitions of the traction of tractor and justify ways to increase the speed of their implementation The conducted analysis made it possible to justify, that method evaluating the traction properties of tractor on the measurement of its accelerations on moving is the best method. Based on the results of experimental research, a conclusion was made about the need for a theoretical research of the effectiveness of tractor ballasting.

The article based on well-known publications summarizes the results of research on the energy saving of generalpurpose tractors, based on the analysis of the specific traction resistances of agricultural machines aggregated with the tractor. The well-known method of estimating the resistance to the movement of agricultural machines based on the acceleration of the tractor acceleration is analyzed. The unsolved problem of energy saving of the tractor unit with GPS in the precision farming system is formulated. The energy saving of the tractor is considered to be one of the most costeffective, for the assessment of which the various publications have suggested different methods. But they is not primed on the method of assigning specific work (on unit of work) to fuel consumption a tractor unit, even when we are has the information of elemental energy consumption. It is recommended to evaluate the energy consumption of the tractor during the technological process behind the traction resistance of the machines by the difference in the acceleration of the tractor acceleration.

Introduction. The human immunodeficiency virus (HIV) protein p24 plays an important role in the life cycle of the virus, and also is a target for diagnostic tests and for new antiretroviral drugs and therapeutic vaccines. The most studied variant of HIV-1 in the world is subtype B. In Russia, the most common variant is A6, the spread of recombinant forms (CRF63_02A6, CRF03_A6B) is observed as well as circulation of G and CRF02_AG variants. However, a detailed study of the p24 protein in these variants has not yet been conducted. The aim was to study the features of the p24 protein in HIV-1 variants circulating in Russia and estimate the frequency of occurrence of pre-existing mutations associated with resistance to lenacapavir, the first antiretroviral drug in the class of capsid inhibitors. Materials and methods. The objects of the study were the nucleotide sequences obtained from the Los Alamos international database and clinical samples from HIV infected patients. Results and discussion. The features of HIV-1 variants circulating in Russia have been determined. V86A, H87Q, I91F are characteristic substitutions in A6 genome. It is shown that the presence of preexisting mutations associated with resistance to lenacapavir is unlikely. Conclusion. Features of the p24 protein in HIV-1 variants circulating in Russia allow them to be distinguished from others variants and among themselves. The prognosis for the use of lenacapavir in Russia is generally favorable. The results obtained could be taken into account in developing and using antiretroviral drugs and therapeutic vaccines.

The placenta has a unique hypomethylated genome. Due to this feature of the placenta, there is a potential possibility of using regulatory elements derived from retroviruses and retrotransposons, which are suppressed by DNA methylation in the adult body. In addition, there is an abnormal increase in the level of methylation of the LINE-1 retrotransposon in the chorionic trophoblast in spontaneous abortions with both normal karyotype and aneuploidy on different chromosomes, which may be associated with impaired gene transcription using LINE-1 regulatory elements. To date, 988 genes that can be expressed from alternative LINE-1 promoters have been identified. Using the STRING tool, genes (NUP153 and YWHAB) were selected, the products of which have significant functional relationships with proteins highly expressed in the placenta and involved in trophoblast differentiation. This study aimed to analyze the expression of the NUP153 and YWHAB genes, highly active in the placenta, from canonical and alternative LINE-1 promoters in the germinal part of the placenta of spontaneous and induced abortions. Gene expression analysis was performed using real-time PCR in chorionic villi and extraembryonic mesoderm of induced abortions (n = 10), adult lymphocytes (n = 10), spontaneous abortions with normal karyotype (n = 10), and with the most frequent aneuploidies in the first trimester of pregnancy (trisomy 16 (n = 8) and monosomy X (n = 6)). The LINE-1 methylation index was assessed in the chorionic villi of spontaneous abortions using targeted bisulfite massive parallel sequencing. The level of expression of both genes from canonical promoters was higher in blood lymphocytes than in placental tissues (p < 0.05). However, the expression level of the NUP153 gene from the alternative LINE-1 promoter was 17 times higher in chorionic villi and 23 times higher in extraembryonic mesoderm than in lymphocytes (p < 0.05). The expression level of NUP153 and YWHAB from canonical promoters was higher in the group of spontaneous abortions with monosomy X compared to all other groups (p < 0.05). The LINE-1 methylation index negatively correlated with the level of gene expression from both canonical (NUP153 – R = –0.59, YWHAB – R = –0.52, p < 0.05) and alternative LINE-1 promoters (NUP153 – R = –0.46, YWHAB – R = –0.66, p < 0.05). Thus, the observed increase in the LINE-1 methylation index in the placenta of spontaneous abortions is associated with the level of expression of the NUP153 and YWHAB genes not only from alternative but also from canonical promoters, which can subsequently lead to negative consequences for normal embryogenesis.

The genome-wide variant of the chromatin conformation capture technique (Hi-C) is a powerful tool for revealing patterns of genome spatial organization, as well as for understanding the effects of their disturbance on disease development. In addition, Hi-C can be used to detect chromosomal rearrangements, including balanced translocations and inversions. The use of the Hi-C method for the detection of chromosomal rearrangements is becoming more widespread. Modern high-throughput methods of genome analysis can effectively reveal point mutations and unbalanced chromosomal rearrangements. However, their sensitivity for determining translocations and inversions remains rather low. The storage of whole blood samples can affect the amount and integrity of genomic DNA, and it can distort the results of subsequent analyses if the storage was not under proper conditions. The Hi-C method is extremely demanding on the input material. The necessary condition for successfully applying Hi-C and obtaining high-quality data is the preservation of the spatial chromatin organization within the nucleus. The purpose of this study was to determine the optimal storage conditions of blood samples for subsequent Hi-C analysis. We selected 10 different conditions for blood storage and sample processing. For each condition, we prepared and sequenced Hi-C libraries. The quality of the obtained data was compared. As a result of the work, we formulated the requirements for the storage and processing of samples to obtain high-quality Hi-C data. We have established the minimum volume of blood sufficient for conducting Hi-C analysis. In addition, we have identified the most suitable methods for isolation of peripheral blood mononuclear cells and their long-term storage. The main requirement we have formulated is not to freeze whole blood.

Miscarriage is an important problem in human reproduction, affecting 10–15 % of clinically recognized pregnancies. The cases of embryonic death can be divided into missed abortion (MA), for which the ultrasound sign of the embryo death is the absence of cardiac activity, and anembryonic pregnancy (AP) without an embryo in the gestational sac. The aim of this study was to compare the frequency of chromosomal abnormalities in extraembryonic tissues detected by conventional cytogenetic analysis of spontaneous abortions depending on the presence or absence of an embryo. This is a retrospective study of 1551 spontaneous abortions analyzed using GTG-banding from 1990 to 2022 (266 cases of AP and 1285 cases of MA). A comparative analysis of the frequency of chromosomal abnormalities and the distribution of karyotype frequencies depending on the presence of an embryo in the gestational sac was carried out. Statistical analysis was performed using a chi-square test with a p < 0.05 significance level. The total frequency of chromosomal abnormalities in the study was 53.6 % (832/1551). The proportion of abnormal karyotypes in the AP and MA groups did not differ significantly and amounted to 57.1 % (152/266) and 52.9 % (680/1285) for AP and MA, respectively (p = 0.209). Sex chromosome aneuploidies and triploidies were significantly less common in the AP group than in the MA group (2.3 % (6/266) vs 6.8 % (88/1285), p = 0.005 and 4.9 % (13/266) vs 8.9 % (114/1285), p = 0.031, respectively). Tetraploidies were registered more frequently in AP compared to MA (12.4 % (33/266) vs. 8.2 % (106/1285), p = 0.031). The sex ratio among abortions with a normal karyotype was 0.54 and 0.74 for AP and MA, respectively. Thus, although the frequencies of some types of chromosomal pathology differ between AP and MA, the total frequency of chromosomal abnormalities in AP is not increased compared to MA, which indicates the need to search for the causes of AP at other levels of the genome organization, including microstructural chromosomal rearrangements, monogenic mutations, imprinting disorders, and epigenetic abnormalities.

BACKGROUND: Melanocortins, including -melanocyte stimulating hormone (MSH), MSH, MSH, and adrenocorticotropic hormone, are products of the polypeptide proopiomelanocortin. These products bind to five different melanocortin receptors (MC1R, MC2R, MC3R, MC4R, MC5R) with different affinities. Because MC3R and MC4R are the major types expressed in the brain, these two receptors can mediate the behavioral effects of melanocortins. AIM: To clear the role of MC4R in sexual behavior of male rats after social isolation from relatives. MATERIALS AND METHODS: In the present study, 40 naive male Wistar rats divided into 4 groups, 3 of which were grown in complete social and partial sensory isolation, received saline, PT-141 (MC3R/MC4R agonist) in a dose 0.3 g intraperitoneally, and THIQ (MC4R agonist) in a dose 0.1 g intranasally. Behavioral effects were registered in a cage with unreachable reinforcement in which the female in the estrus phase, separated by a transparent perforated barrier, was kept for 10 minutes under red light. Blood samples were taken 30 minutes after administration from the tail vein. Testosterone concentrations were measured by ELISA. RESULTS: Social isolation had no significant effect on latent time before trying to reach a female but decreased the time spent near the cage with a female. Isolated animals did not show genital grooming acts during the experiment. PT-141 decreased the latent time to approach the female, increased the time spent near the female cage, and stimulated genital grooming. THIQ decreased the latent time to reach a female and stimulated genital grooming. At the same time, THIQ had no effect on the time spent near the female cage. Social isolation reduced testosterone levels more than twice compared to controls. The administration of PT-141 and THIQ had no effect on testosterone concentration. CONCLUSIONS: The results confirm the depressing effect of chronic social isolation stress on the sexual motivation of male rats and demonstrate different roles of melanocortin MC3R/MC4R receptors in the realization of sexual behavior.

The joint intercalation of Co and Fe atoms under a graphene buffer layer synthesized on a SiC(0001) single crystal has been studied. Intercalation has been performed by means of the alternating deposition of ultrathin Fe and Co metal films on the substrate heated to 450°C with the subsequent heating to 600°C in 15 min. It has been shown that Co and Fe atoms under these conditions are intercalated under graphene, forming compounds with silicon and with each other. The existence of a magnetic order in the system up to room temperature has been demonstrated using a superconducting quantum interferometer. A possible stoichiometry of the formed alloys has been analyzed using data on the shape and magnitude of hysteresis loops. In addition, it has been found that Fe and Co in the system exposed to the atmosphere are not oxidized. Thus, graphene protects the formed system. This study makes contribution to the investigation of graphene in contact with magnetic metals and promotes its application in spintronic and nanoelectronic devices.