bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of the Vibrational Behavior of a Bolted Beam in the Presence of Friction
Authors:   Université des Sciences et de la Technologie Houari Boumediene, Hamouda K. ,   Université des Sciences et de la Technologie Houari Boumediene, Bournine H. ,   Université des Sciences et de la Technologie Houari Boumediene, Brahimi K. ,   Université des Sciences et de la Technologie Houari Boumediene, Chekirou F. ,   Laboratoire de Mécanique des Structures (LMS), EMP, Benkajouh T. ,   Université des Sciences et de la Technologie Houari Boumediene, Haddad M. ,   Laboratoire de Tribologie et Dynamique des Systèmes (LTDS), Ecole Centrale de Lyon, Bot A. Le
Published: April 2022

This paper presents the effect of friction-induced vibration between two beams in relative motion according to Timoshenko’s beam theory. This system is composed of two cantilever beams screwed together, allowing friction force to occur in the contact interface. The nonlinear behavior can be divided into two phases: stick and slip. The differential equations of motion in the two phases are developed, with the precision of the transition condition between each phase. A number of experiments are carried out in order to validate the theoretical model, the main contribution of which is to test these specimens in modes greater than one. The experiments demonstrate the influence of changing the clamping force on the stiffness of the structure and thus on its frequency and damping ratio. The comparison between theory and experiments reveals a good agreement. In addition, the tests show an increase in the modal damping ratio when the frequencies are increased. This leads to a considerable increase in energy dissipation by the structure, making it a good choice as a friction damper.
Validation of RANS Turbulence Models for the Conjugate Heat Exchange Problem
Authors:   Kalashnikov Izhevsk State Technical University, Chernova A. A.
Published: April 2022

This paper addresses problems of mathematical modeling of heat exchange processes in the pre-nozzle volume of a solid propellant rocket engine with a charge with starlike cross-section and a recessed hinged nozzle. Methods of mathematical modeling are used to solve the quasi-stationary spatial conjugate problem of heat exchange. An analysis is made of the influence of RANS turbulence models on the flow structure in the flow channels of the engine and on the computed heat flow distributions over the surface of the recessed nozzle. Methods of mathematical modeling are used to solve the quasi-stationary spatial conjugate problem of heat exchange. Results of validation of RANS turbulence models are presented using well-known experimental data. A comparison of numerical and experimental distributions of the heat-transfer coefficient over the inlet surface of the recessed nozzle for the engine with a cylindrical channel charge is made for a primary choice of turbulence models providing a qualitative agreement between calculated and experimental data. By analyzing the results of numerical modeling of the conjugate problem of heat exchange in the combustion chamber of the solid propellant engine with a starlike channel, it is shown that the SST $k-\omega$ turbulence model provides local heat-transfer coefficient distributions that are particularly close to the experimental data.
Nonlocal Constants of Motions of Equations of Painlevé – Gambier Type and Generalized Sundman Transformation
Authors:   Department of Mathematics, Khalifa University of Science and Technology, Guha P. ,   Department of Physics, Diamond Harbour Women’s University, Choudhury A. G. ,   Sailendra Sircar Vidyalaya, Khanra B. ,   School of Mathematical, Statistical, Acturial and Computer Sciences, University of KwaZulu-Natal, Leach P. G. L.
Published: April 2022

We describe a method to generate nonlocal constants of motion for a special class of nonlinear ODEs. We employ the method of the generalized Sundman transformation to obtain certain new nonlocal first integrals of autonomous second-order ordinary differential equations belonging to the classification scheme developed by Painlevé and Gambier.
Asymptotics of Dynamical Saddle-node Bifurcations
Authors:   Institute of mathematics with computing center UFRC RAS, Kalyakin L. A.
Published: April 2022

Dynamical bifurcations occur in one-parameter families of dynamical systems, when the parameter is slow time. In this paper we consider a system of two nonlinear differential equations with slowly varying right-hand sides. We study the dynamical saddle-node bifurcations that occur at a critical instant. In a neighborhood of this instant the solution has a narrow transition layer, which looks like a smooth jump from one equilibrium to another. The main result is asymptotics for a solution with respect to the small parameter in the transition layer. The asymptotics is constructed by the matching method with three time scales. The matching of the asymptotics allows us to find the delay of the loss of stability near the critical instant.
Lower reporting rates after two decades for most bird species at a Wet Tropics Field Station
Authors:   The School for Field Studies, Centre for Rainforest Studies, P.O. Box 141, Yungaburra QLD 4884, Australia, Kowalski Michael ,   325 South Drive, Paramus, New Jersey 07652, United States of America, Soifer Lydia ,   The School for Field Studies, Centre for Rainforest Studies, P.O. Box 141, Yungaburra QLD 4884, Australia,   Forest Ecology and Conservation Group, Department of Plant Sciences, University of Cambridge Conservation Research Institute, Cambridge, United Kingdom, Craig Michael ,   The School for Field Studies, Centre for Rainforest Studies, P.O. Box 141, Yungaburra QLD 4884, Australia,   School of Biological Sciences, University of Western Australia, Nedlands WA 6009, Australia, Freeman Amanda ,   The School for Field Studies, Centre for Rainforest Studies, P.O. Box 141, Yungaburra QLD 4884, Australia,   Nature North, P.O. Box 1536, Atherton QLD 4883, Australia
Published: April 2022

Across Australia’s Wet Tropics region, populations of rainforest-dependent birds have declined because of climate change. Reforestation and regenerating secondary forest on abandoned agricultural land may help bolster species’ populations by expanding and connecting habitat. However, little is known about the value of these habitats for rainforest birds, or the impacts of climate change on secondary forests and their fauna compared with primary forests. At a 62-ha, mid-elevation property with primarily secondary forest cover on the Atherton Tablelands, in the Wet Tropics region, Queensland, we examined changes in bird species reporting rates on weekly lists between 2000–2005 and 2014–2019. Reporting rates of grassland and eucalypt-forest species decreased as expected because the area of ungrazed pasture was reduced over time, while the area occupied by tree plantings and naturally regenerating forest increased and matured. Reporting rates of most mixed-forest (61%) and nearly half (47%) of rainforest-dependent bird species also decreased significantly between the two time periods, despite the quality of rainforest habitat improving at the site. We infer that climate change is the cause of these declines. Five of the rainforest-dependent bird species whose reporting rates decreased in this study are known to have moderately increased in abundance in mid-elevation primary forest. Hotter, drier secondary forests may not be as well buffered as primary forest from the impacts of climate change, reducing their suitability as habitat for many bird species such as these. However, further studies are needed in secondary forests to investigate this.
A Reliability-Enhanced Differential Sensing Amplifier for Hybrid CMOS/MTJ Logic Circuits
Authors: Wang Chengzhi , Wang Huiquan , Wang Dognsheng , Fang Jian , Wang Lu , Zhang Guangda
Published: April 2022

Recently, hybrid logic circuits based on magnetic tunnel junctions (MTJs) have been widely investigated to realize zero standby power. However, such hybrid CMOS/MTJ logic circuits suffer from a severe sensing reliability due to the limited tunnel magnetoresistance ratio (TMR≤150%) of the MTJ and the large process variation in the deep sub-micrometer technology node. In this paper, a novel differential sensing amplifier (DSA) is proposed, in which two PMOS transistors are added to connect the discharging branches and evaluation branches. Owing to the positive feedback realized by these two added PMOS transistors, it can achieve a large sensing margin. By using an industrial CMOS 40 nm design kit and a physics-based MTJ compact model, hybrid CMOS/MTJ simulations have been performed to demonstrate its functionality and evaluate its performance. Simulation results show that it can achieve a smaller sensing error rate of 9% in comparison with the previously proposed DSAs with the TMR ratio of 100% and process variation of 10%, while maintaining almost the same sensing delay of 74.5 ps and sensing energy of 1.92 fJ/bit.
Multi-Scale Modelling of Fuel Droplet Heating and Evaporation in Combustion Engines
Authors: Xie Jianfei
Published: April 2022

This review summarises the main numerical models of fuel droplet heating and evaporation (DHE) in combustion engines across the different scales by accessing the nano/micro, meso and macroscopic fluid elements. The phenomena of multi-physics, multi-scale and multi-phase fluid flow and heat transfer are fully investigated when the fuel droplet (dodecane) is heating and evaporated into a background gas (nitrogen) crossing the liquid-vapour (LV) interface, kinetic region (i.e., Knudsen layer) and the bulk regions of liquid and gas in terms of molecular dynamics (MD) simulations, kinetic theory modelling (i.e., direct numerical solutions of Boltzmann equations) and convectional fluid dynamics approach, respectively. The evaporation coefficient of fuel evaporating molecules and their velocity distributions at the LV interface derived from MD simulations formulate a new kinetic boundary condition (KBC). Moreover, a novel kinetic model considering the inelastic collision between fuel molecules alongside the new KBC enables us to describe the non-equilibrium gas dynamics of fuel vapour and gas mixture in Knudsen layer (KL). Heat and mass flux analysis of the fuel droplet under combustion engine conditions can be accurately assessed by implementing the inelastic collision between fuel molecules in KL and a temperature-dependent evaporation coefficient at the LV interface into DHE. The surface temperature of fuel droplet and its evaporation time, which play a significant role in resolving the ignition delay and hence the combustion phasing in engines, can also be well estimated. The multi-scale modelling of fuel DHE will make significantly potential input into the cleaner engine targeting the low-carbon emissions and enhance the capability of the existing computational fluid dynamics (CFD) solvers.
Functional Data Analysis for Imaging Mean Function Estimation: Computing Times and Parameter Selection
Authors: Arias López Juan , Cadarso Suárez Carmen , Aguiar Fernández Pablo
Published: April 2022

Functional Data Analysis (FDA) is a relatively new field of statistics dealing with data expressed in the form of functions. FDA methodologies can be easily extended to the study of imaging data, an application proposed in Wang et al. (2020), where the authors settle the mathematical groundwork and properties of the proposed estimators. This methodology allows for the estimation of mean functions and simultaneous confidence corridors (SCC), also known as simultaneous confidence bands, for imaging data and for the difference between two groups of images. This is especially relevant for the field of medical imaging, as one of the most extended research setups consists on the comparison between two groups of images, a pathological set against a control set. FDA applied to medical imaging presents at least two advantages compared to previous methodologies: it avoids loss of information in complex data structures and avoids the multiple comparison problem arising from traditional pixel-to-pixel comparisons. Nonetheless, computing times for this technique have only been explored in reduced and simulated setups (Arias-López et al., 2021). In the present article, we apply this procedure to a practical case with data extracted from open neuroimaging databases and then measure computing times for the construction of Delaunay triangulations, and for the computation of mean function and SCC for one-group and two-group approaches. The results suggest that previous researcher has been too conservative in its parameter selection and that computing times for this methodology are reasonable, confirming that this method should be further studied and applied to the field of medical imaging.
Assessment of risk factors and pregnancy outcomes in women with thrombotic microangiopathy in Ain Shams University Maternity Hospital over a 5-year period
Authors:   Ain Shams University, Cairo, Egypt, Abdelnasser A.G. , Helal M.M. ,   Ain Shams University, Cairo, Egypt, Ramy A.R. ,   Ain Shams University, Cairo, Egypt, Zaki H.V. ,   Ain Shams University, Cairo, Egypt, Ali R.M. ,   Ain Shams University, Cairo, Egypt, Abdelrahman R.M. ,   Ain Shams University, Cairo, Egypt
Published: April 2022

Thrombotic microangiopathy in pregnancy can lead to maternal and fetal life-threatening adverse events. Objective. To study the demographic characteristics (age, parity), risk factors, treatment modalities, and pregnancy outcomes in women with thrombotic microangiopathy in Ain Shams University Maternity Hospital over a 5-year period. Patients and methods. This study was retrospectively conducted at Ain Shams University Maternity Hospital and included 419 patients; the study population were pregnant women admitted to the hospital from January 2014 to December 2018, with pregnancy-associated thrombotic microangiopathy. The study was performed through revising the medical records in the archive and the ICU and contacting the patients to assess demographic data, risk factors, presentation of the patient, type of the syndrome, and the maternal and fetal outcome. Results. HELLP syndrome was the most common pregnancy complication. In most of cases, women delivered by cesarean section (72.1%). Complications included chronic hypertension (CHTN), acute kidney injury (AKI), chronic kidney injury (CKI). Maternal mortality was significantly more frequent in hemolytic uremic syndrome (HUS). Maternal mortality was 8.8 %, and neonatal mortality was 26.7%. Most of women were admitted to the ICU (87.1%). Conclusion. Thrombotic microangiopathy in pregnancy continues to pose a large challenge to obstetricians, immunologists, and nephrologists due to potential risks and complications. Pregnancy outcome is more optimistic when termination of pregnancy occurs early in the disease with the possible use of corticosteroids with or without plasma exchange transfusion under the control of a multidisciplinary approach team. Key words: risk factors, outcome, pregnant women, thrombotic microangiopathy
Targeted therapy for pelvic pain associated with endometriosis. Assessment of quality of life and sexual function
Authors:   Saint Petersburg State Pediatric Medical University, Saint Petersburg, Russian Federation, Rukhlyada N.N. , Krylov K.Yu. ,   Saint Petersburg I.I.Dzhanelidze Research Institute of Emergency Medicine, Saint Petersburg, Russian Federation, Biryukova E.I. ,   Saint Petersburg I.I.Dzhanelidze Research Institute of Emergency Medicine, Saint Petersburg, Russian Federation, Tsechoeva L.Sh. ,   Saint Petersburg I.I.Dzhanelidze Research Institute of Emergency Medicine, Saint Petersburg, Russian Federation, Vinnikova S.V. ,   Saint Petersburg I.I.Dzhanelidze Research Institute of Emergency Medicine, Saint Petersburg, Russian Federation
Published: April 2022

Objective. To study the efficacy of dienogest 2 mg in the treatment of female patients with pelvic pain associated with endometriosis in terms of improving the quality of life and sexual function. Patients and methods. The study group included 54 female patients with confirmed diagnosis of genital endometriosis (adenomyosis, infiltrating endometriosis, ovarian endometrial cysts). Dienogest 2 mg once daily was prescribed to all patients; 38 patients received non-steroidal anti-inflammatory drugs and constituted the comparison group. The visual analogue scale was used to assess pelvic pain, dysmenorrhea, and dyspareunia in patients with endometriosis. The 36-Item Short Form Survey (SF-36), the Female Sexual Function Index (FSFI), and the Female Sexual Distress Scale (FSDS) were used to assess the quality of life, sexual function, and sexual distress, respectively. The study contained two consecutive follow-ups after 3 and 6 months. All patients included in the study refused the proposed surgical treatment. Results. A slight decrease in chronic pelvic pain, dysmenorrhea, and dyspareunia was observed in the study group after 3 months (p < 0.05) with a progressive decrease in pain intensity by 6 months of dienogest administration (p < 0.001). The qualityof-life assessment showed a similar tendency: improvements were significant in several categories after 3 months (p < 0.05) and in all categories by 6 months (p < 0.001). The FSFI score had no changes after 3 months of follow-up (p with no statistical significance) but improved between 3 and 6 months (p < 0.001). The same was observed regarding the FSDS scale (p < 0.001). No changes were seen in the comparison group. Conclusion. Administration of dienogest 2 mg once daily in women with endometriosis-associated pelvic pain significantly reduces pain syndrome while positively affecting the quality of life and sexual function. Key words: dyspareunia, endometriosis, chronic pelvic pain, dienogest, quality of life, sexual activity
Adenomyosis and oxidative stress. Rationale for comprehensive approach to treatment of patients of reproductive age
Authors:   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation, Davydov A.I. , Chilova R.A. ,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation, Lebedev V.A. ,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation, Tairova M.B. ,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
Published: April 2022

The analysis of lipid peroxidation (LPO) and antioxidant protection (concentration of α-tocopherol and superoxide dismutase) in the blood serum of patients with adenomyosis was performed. The levels of conjugated dienes (CD), malondialdehyde (MDA), superoxide dismutase (SOD), and α-tocopherol were significantly higher prior to treatment (organ-preserving endoscopy + drug therapy) than those in the control group (patients with tubal infertility). At the same time, SOD activity was almost 2-fold lower, and MDA levels were 2-fold higher compared to the normal values. After surgery, progestogens, magnesium supplements, and indole-3-carbinol+resveratrol (1 tablet once a day for 3 months) were prescribed to all patients. After combination therapy, all the parameters of free radicals and antioxidant protection changed significantly: they did not reach the control values but were close to them to such an extent that the difference between the levels of MDA, CD, SOD, and α-tocopherol in the blood serum of patients in the control group and that of patients with adenomyosis was found to be insignificant. Moreover, the percentage of variation (improvement) of CD and SOD exceeded 40%. Conclusion. Under certain conditions, intrauterine endoscopy in combination with postoperative drug therapy can provide longterm relief of pathognomonic symptoms of adenomyosis. Key words: adenomyosis, reproductive age, antioxidant system, indole-3-carbinol+resveratrol
Efficiency and safety of terlipressin application during caesarian section in pregnant women with a high risk of bleeding: a multicenter comprehensive cohort study of Terli-Bleed. Part III
Authors:   Regional Clinical Center for Maternity and Childhood Protection, Krasnoyarsk, Russian Federation, Raspopin Yu.S. ,   V.F.Voino-Yasenetsky Krasnoyarsk State Medical University, Krasnoyarsk, Russian Federation, Shifman E.M. ,   M.F.Vladimirsky Moscow Regional Research Clinical Institute, Moscow, Russian Federation, Belinina A.A. ,   Altai Regional Clinical Perinatal Center, Barnaul, Russian Federation, Rostovtsev A.V. ,   City Clinical Hospital of Emergency Medical Care No 8, Voronezh, Russian Federation, Artymuk N.V. ,   Kemerovo State Medical University, Kemerovo, Russian Federation, Olenev A.S. ,   City Clinical Hospital No 24, Moscow, Russian Federation,   Institute of Medicine, Peoples' Friendship University of Russia, Moscow, Russian Federation, Tskhay V.B. ,   V.F.Voino-Yasenetsky Krasnoyarsk State Medical University, Krasnoyarsk, Russian Federation,   Federal Medical-Biological Agency of Russia, Moscow, Russian Federation, Alexandrovich Yu.S. ,   Saint Petersburg State Pediatric Medical University, Saint Petersburg, Russian Federation, Molchanova I.V. ,   Altai Regional Clinical Perinatal Center, Barnaul, Russian Federation, Novikova O.N. ,   Kemerovo State Medical University, Kemerovo, Russian Federation, Pylaeva N.Yu. ,   V.I.Vernadsky Crimean Federal University, Simferopol, Russian Federation
Published: April 2022

The search for new means of prevention and treatment of massive obstetric haemorrhage is a priority task for the world scientific community, both obstetricians and anesthesiologists. Previously, we have shown the preventive efficiency of terlipressin, which helps to reduce the volume of blood loss during caesarean section (CS), and its lack of systemic hemodynamic effects when used topically. Objective. To evaluate changes in clinical and laboratory parameters when using terlipressin topically as a means of preventing postpartum haemorrhage during CS in high-risk pregnant women. Patients and methods. This publication is a continuation of our multicenter comprehensive cohort study of Terli-Bleed. The study included 454 pregnant women at high risk for haemorrhage who delivered by CS. They were divided into two groups: a control group (n = 351) and a study group (n = 103), with topical administration of terlipressin injected into the myometrium. Complete blood count, acid-base balance, lactate and hemostasis parameters were analyzed. Results. The levels of hemoglobin, platelets, fibrinogen, lactate, and blood pH were different in the groups during the postoperative follow-up period (p < 0.05). Conclusion. The analysis of clinical and laboratory parameters indicates the preventive ability of terlipressin to reduce the volume of intra- and postoperative haemorrhage without affecting the hemostasis system. Key words: terlipressin, caesarean section, postpartum haemorrhage, clinical and laboratory parameters
Uterine rupture after myomectomy performed before pregnancy
Authors:   N.I.Pirogov Russian National Research Medical University, Moscow, Russian Federation, Savelyeva G.M. , Kurtser M.A. ,   N.I.Pirogov Russian National Research Medical University, Moscow, Russian Federation, Breslav I.Yu. ,   Hospital MD GROUP, Moscow, Russian Federation
Published: April 2022

Objective. To study the incidence and risk factors of uterine rupture (UR) in a scarred uterus after myomectomy during pregnancy and childbirth. Patients and methods. A retrospective analysis of UR after myomectomy during pregnancy and childbirth was carried out according to the study of 43 labor and delivery medical records of patients from various maternity hospitals in Moscow. Results. Uterine scar after myomectomy, especially when performed laparoscopically, in the presence of pronounced interstitial changes poses a significant threat to both the mother and the fetus. In 27 (62.8%) cases, UR occurred before childbirth in a full-term pregnancy. UR in a scarred uterus after myomectomy was characterized by untimely diagnosis and laparotomy in 8 (21.6%) patients, resulted in blood loss of 1,000-5,000 mL in 32 (74.4%) patients; adverse perinatal outcomes: out of 45 children (2 cases of twins), 11 (24.4%) died (2 with extremely low body weight), 4 (8.9%) born with severe asphyxia, 6 (13.3%) with moderate asphyxia, 10 (22.2%) with mild asphyxia. In 5 (11.6%) cases, UR was detected in the early postpartum period. Conclusion. UR in a scarred uterus after myomectomy is characterized by delayed diagnosis and underestimation of early symptoms. Laparotomy was performed when a rupture occurred, both for complete 32 (74.4%) and incomplete 11 (25.6%). Careful choice of surgical approach for myomectomy in patients planning pregnancy and timely assessment of the state of the uterine scar are recommended. In case of UR, organ preservation surgery is performed. Key words: myomectomy, uterine rupture, uterine scar after myomectomy
Cytokine profile in patients with chronic endometritis and reproductive disorders
Authors:   F.I.Inozemtsev Academy of Medical Education, Saint Petersburg, Russian Federation, Dikke G.B. , Sukhanov A.A. ,   Perinatal Medical Centre, Tyumen Region, Tyumen, Russian Federation, Kukarskaya I.I. ,   Perinatal Medical Centre, Tyumen Region, Tyumen, Russian Federation,   Tyumen State Medical University, Tyumen, Russian Federation, Ostromensky V.V. ,   F.I.Inozemtsev Academy of Medical Education, Saint Petersburg, Russian Federation
Published: April 2022

Objective. To study the immune response in patients with chronic endometritis (CE) of viral and bacterial etiology based on the evaluation of cytokine status as well as the efficiency of local therapy using a complex of natural exogenous cytokines. Patients and methods. A prospective randomized clinical trial, which included 76 women with CE and infertility, who received etiotropic antibacterial therapy prior to inclusion in the study, is presented. In group I (n = 36), patients were treated with a daily intravaginal administration of Superlymph 25 U for 20 days; in group II (n = 40), patients were under observation. We used a vaginal wet mount test, real-time polymerase chain reaction (RT-PCR) (to estimate virus shedding), and an analysis of serum cytokine levels (interleukins IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, and tumor necrosis factor alpha (TNF-α)). Results. The herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) (80.6% and 80.0%, respectively) was predominantly detected in both groups of patients in combination with other types of herpesviruses (50.0% and 42.5%, respectively) and/or human papillomavirus (HPV) (50%). After treatment with Superlymph, virus shedding ceased in 66.7% of patients (p < 0.001). Before treatment, the levels of all cytokines were higher than the reference values (p < 0.001) in both groups (IL-1β – 1.8 times, IL-6 – 1.6 times, IL-2 and IL-8 – 1.2 times, TNF-α – 1.4 times). After treatment, their values decreased in group I (p < 0.001 for each indicator). In group II, the changes were insignificant. Pregnancy occurred within 12 months in 30 (83.3%) patients in group I and in 24 (60.0%) patients in group II, and this result was statistically significantly higher in group I (p = 0.047). Conclusion. The role of viral and bacterial infections accompanied by an imbalance of pro- and anti-inflammatory cytokines in patients with CE was revealed, which is the basis for prescribing not only antibacterial therapy, but also local immunomodulatory agents. Key words: infertility, immunity, Superlymph, chronic endometritis, cytokines
Proteomic analysis of amniotic fluid and identification of gasotransmitter-producing proteins as markers of complicated pregnancy and prediction of postpartum pathology
Authors:   Rostov State Medical University, Rostov-on-Don, Russian Federation, Pogorelova T.N. , Gunko V.O. ,   Rostov State Medical University, Rostov-on-Don, Russian Federation, Nikashina A.A. ,   Rostov State Medical University, Rostov-on-Don, Russian Federation, Mikhelson A.A. ,   Rostov State Medical University, Rostov-on-Don, Russian Federation, Lebedenko E.Yu. ,   Rostov State Medical University, Rostov-on-Don, Russian Federation, Fabrikant A.D. ,   Rostov State Medical University, Rostov-on-Don, Russian Federation, Bespalaya A.V. ,   Rostov State Medical University, Rostov-on-Don, Russian Federation
Published: April 2022

Objective. To study the amniotic fluid proteome, to identify gasotransmitter-producing proteins and to evaluate their role as markers of pre-eclampsia (PE) and prediction of the early neonatal period course. Patients and methods. Fifty-eight women were examined. The study group included 28 women who had pregnancy complicated by PE; the control group consisted of 30 women with normal pregnancy. The protein composition of amniotic fluid was determined by high resolution two-dimensional electrophoresis and time-of-flight mass spectrometry. Sulfur-containing proteins, which are the sources of gasotransmitter SH2, were identified according to standard normal tables. Results. It was found that the development of PE is accompanied by significant changes in the amniotic fluid proteome. Four sulfur-containing proteins were found to be absent: retinol-binding protein (S-S- and SH-groups); fatty-acid-binding protein (S-S-groups); carbonyl reductase NAD+ (SH-groups), and haptoglobin (SH-groups). These proteins are involved in cell protection against oxidative and carbonyl stress, in maintaining the integrity of biomembranes and providing the fetus with necessary nutrients. Two additional membrane-bound proteins with high level secretion were found in women with PE, which also contribute negatively to the development of this obstetric pathology due to their pro-inflammatory and pro-oxidant properties. Conclusion. The revealed protein imbalance may be one of the primary factors of molecular disorders in the fetoplacental complex in PE. Key words: gasotransmitters, amniotic fluid, pre-eclampsia, proteomic composition, sulfur-containing proteins
Features of central hemodynamics, functional status of lower extremity venous system and perinatal outcomes in pregnant women with early stages of phlebopathy
Authors:   Kazan State Medical Academy – Branch Campus of the FSBEI FPE RMACPE MOH Russia, Kazan, Russian Federation, Iupatov E.Iu.
Published: April 2022

Objective. To study the features of functional status of veins and central hemodynamics in women with early stages of phlebopathy during pregnancy and their role in perinatal outcomes. Patients and methods. Seventy pregnant women with early manifestations of chronic venous disorders were examined. The study group included 30 patients who gave birth to children with signs of ante-, intra-, postnatal hypoxia; the control group included 40 patients with normal physiological birth outcomes for newborns. When assessing the status of venous system, the elasticity index was calculated, and the severity of sludge syndrome was identified. Volumetric compression oscillometry was used to measure several central hemodynamic parameters in the second trimester. The relative gene expression of HIF1α transcription factor was calculated in the second and third trimesters. Morphological examination of the placenta was performed with determining the fetoplacental ratio and placental weight (g). Results. There was a statistically significant increase in the elasticity index during gestation in pregnant women in the study group. The first stage of sludge syndrome in the second trimester was detected in 70% of pregnant women in the study group, and the second stage of sludge syndrome was detected in 16.6% of patients. The relative expression of HIF1α in patients in the study group increased more than 2.5-fold in the second trimester and more than 3.5-fold in the third trimester. Pregnant women in the study group had statistically significant changes in all central hemodynamic parameters as compared with the control group. All women required emergency delivery. Fetal weight in the study group was statistically lower than in the control group. Apgar score at 1 minute of life in the study group was 6.5 (6; 7) and at 5 minutes – 7.5 (7; 8), in the control group it was 8 (8; 8) and 9 (8; 9), respectively (p > 0.001). The revealed changes in the placentas from women in the study group corresponded to hypoxic tissue injuries. Conclusion. Pregnant women with early stages of phlebopathy have specific features of central hemodynamics and venous functional status, which determine perinatal outcomes. Key words: pregnancy, phlebopathy, hemodynamics in pregnant women, placental morphology
Surgery as a method of immunocorrection
Authors:   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation, Davydov A.I. , Popkov S.A. ,   A.I.Yevdokimov Moscow State University of Medicine and Dentistry, Moscow, Russian Federation,   N.A.Semashko Railroad Clinical Hospital, Moscow, Russian Federation, Utisheva E.V. ,   N.A.Semashko Railroad Clinical Hospital, Moscow, Russian Federation, Kuznetsov R.E. ,   S.P.Botkin City Clinical Hospital, Moscow, Russian Federation, Makeeva D.I. ,   N.A.Semashko Railroad Clinical Hospital, Moscow, Russian Federation, Smirnova L.E. ,   A.I.Yevdokimov Moscow State University of Medicine and Dentistry, Moscow, Russian Federation,   N.A.Semashko Railroad Clinical Hospital, Moscow, Russian Federation, Stromskaya U.A. ,   A.I.Yevdokimov Moscow State University of Medicine and Dentistry, Moscow, Russian Federation, Murakov S.V. ,   Academy of Postgraduate Education, Moscow, Russian Federation, Chilova R.A. ,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
Published: April 2022

Deformity of the uterine cervix is often accompanied by immunological disorders in the cervical mucus, chronic inflammation, cellular changes in the columnar epithelium with several other changes, which eventually leads to the failure of the cervix as a “biological valve” of the female reproductive system. Identification of the pathogenesis underlying the development of these disorders is an important task for modern gynecology aimed at restoring the function of the cervix. Objective. To provide pathophysiological rationale for reconstructive plastic surgery as a method of correction of mucosal immunological homeostasis. Patients and methods. A total of 94 women were examined: 64 of them (the study group) underwent cervical reconstructive surgery by the flap technique of complete layer-by-layer dissection; 30 women were included in the control group. The levels of immunoglobulins and proinflammatory cytokines in the cervical mucus were determined in all patients of the study group before surgery and 6 months after it. Immunological tests were also performed in the control group (once). Results. Satisfactory surgical outcomes were achieved among all observations. The analysis of immunoglobulins and cytokine profile showed that immunological parameters were restored in 90% of patients with initially “moderate” abnormalities and in 75% of patients with initially “severe” abnormalities. Conclusion. The efficacy of reconstructive surgery using complete layer-by-layer dissection technique for cervical deformity in restoring the immunological homeostasis of the cervical mucus was proved, and the pathophysiological mechanisms of this effect were substantiated. Key words: cervix, cervical mucus, deformity, immunoglobulins, cytokine profile, immunological homeostasis
Influence of ABCB1 gene polymorphism encoding P-glycoprotein on congenital malformations
Authors:   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation, Pikuza T.V. , Chilova R.A. ,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation, Sokova E.A. ,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation, Kazakov R.E. ,   Scientific Centre for Expert Evaluation of Medicinal Products, Moscow, Russian Federation, Trifonova N.S. ,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation, Zhukova E.V. ,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation, Shikh E.V. ,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
Published: April 2022

Objective. To assess the influence of the ABCB1 gene polymorphism on the risk of congenital malformations (CM) among pregnant women in the Russian Federation. Patients and methods. This prospective study included 170 mother–baby pairs. The study group consisted of 87 pairs and included children with CM. The control group included 83 pairs without CM in children. Genotyping of the ABCB1 gene polymorphism rs1045642 in mothers and children in the study group and in mothers in the control group was performed by CFX-96 real-time PCR amplification. The frequencies of alleles and genotypes in children with folate-dependent and folateindependent malformations were analyzed in children and their mothers. Results. No association of CM with the ABCB1 gene polymorphism rs1045642 was found. However, women who gave birth to children with CM tended to have a lower frequency of the 3435T allele and the 3435TT genotype and a higher frequency of the 3435CC genotype. Significant differences in the frequencies of the gene polymorphism rs1045642 (p = 0.036) were observed among women who gave birth to children with folate-dependent and folate-independent CM, which was associated with a higher frequency of heterozygous genotype 3435ST in the mothers of children with folate-independent CM. This result needs to be confirmed by further studies. Conclusion. Significant differences in the frequencies of the genotypes of rs1045642 polymorphism in women who gave birth to children with folate-dependent and folate-independent CM were revealed. Key words: congenital malformations, P-glycoprotein, ABCB1 gene polymorphism
Fibulin-5 (FBLN5) gene polymorphisms and cervical insufficiency
Authors:   Lomonosov Moscow State University, Moscow, Russian Federation, Fotina E.V. , Balatskiy A.V. ,   Lomonosov Moscow State University, Moscow, Russian Federation, Zaitseva N.I. ,   Lomonosov Moscow State University, Moscow, Russian Federation, Revina D.B. ,   Lomonosov Moscow State University, Moscow, Russian Federation, Alekseenkova M.V. ,   Lomonosov Moscow State University, Moscow, Russian Federation, Panina O.B. ,   Lomonosov Moscow State University, Moscow, Russian Federation
Published: April 2022

Objective. To study the role of fibulin-5 (FBLN5) gene polymorphisms in the genesis of cervical insufficiency (CI). Patients and methods. This observational retrospective study included 49 patients with clinical manifestations of CI and 31 patients without history of CI. Four most studied single-nucleotide polymorphisms (SNPs) in the FBLN5 gene were selected: rs2284337, rs2018736, rs2474028, rs12589592. DNA was extracted from whole venous blood, and genotyping was performed by polymerase chain reaction (PCR). STATISTICA 12.0 and SNPstats software packages were used for statistical data processing. Results. It was found that the rs2474028(T) allele of the FBLN5 gene is associated with a risk of developing CI (p = 0.0019). In addition, a comparison of a high-risk CI subgroup and a control group revealed that carriage of the heterozygous rs2018736(A/C) or the heterozygous rs12589592(A/G) genotypes of the FBLN5 gene is protective and reduces the risk of developing CI (p = 0.019 and p = 0.0021, respectively). Conclusion. The presence of single-nucleotide polymorphisms in the FBLN5 gene is associated with the development of CI. Key words: cervical insufficiency, pathogenesis, fibulin-5, FBLN5, SNP
Current concept of cerebral dysfunction in COVID-19 patients
Authors:   Central Research Institute of Epidemiology of The Federal Service on Customers' Rights Protection and Human Well-being Surveillance, Moscow, Russian Federation, Maleev V.V. , Vedinov S.M. ,   Specialized Clinical Infectious Diseases Hospital, Krasnodar, Russian Federation, Gorodin V.N. ,   Kuban State Medical University, Krasnodar, Russian Federation
Published: April 2022

There have been very few studies analyzing neuropsychiatric aspects of COVID-19 and the impact of somatic aspects of infection on the development of transient or persistent deficits in higher cerebral functions. This is primarily due to the small number of specialists in neuropsychiatry who work with COVID-19 patients and also because the healthcare system is primarily focused on the diagnosis and treatment of the somatic pathology. In this review, we analyzed the studies assessing the neuropsychiatric aspects of COVID-19 with a focus on possible somatic predictors of their development. We discuss neuropsychiatric manifestations of cerebral dysfunction in patients with new coronavirus infection and provide a description of the dynamics of symptom development and regression. We also cover the issues related to stress resistance of healthcare professionals working with COVID-19 patients. Particular attention is paid to the treatment of COVID-associated cerebral dysfunction and therapeutic options of neuroprotection. Key words: new coronavirus infection, COVID-19, delirium, postcovid neuropsychiatric syndrome, cognitive deficit, suicidal tendencies, encephalopathy
Problems of vaccination and ways to optimize it: a review of randomized clinical trials evaluating Anaferon for children
Authors:   Russian Medical Academy of Continuous Professional Education, Moscow, Russian Federation, Zaplatnikov A.L. , Kondyurina E.G. ,   Novosibirsk State Medical University, Novosibirsk, Russian Federation
Published: April 2022

In this article, we discuss the problem of improving vaccination efficacy in children using an antiviral drug with an immunomodulatory effect Anaferon for children produced in Russia. We analyzed the results of randomized clinical trials (RCTs) evaluating the efficacy and safety of Anaferon for children during vaccination against influenza and pneumococcal infection, including that in children with frequent respiratory infections. According to RCT, Anaferon for children used for the prevention of acute respiratory viral infections (ARVI) in combination with specific immunoprophylaxis of influenza and pneumococcal infection, increased the vaccination coverage by reducing the frequency of ARVI episodes before vaccination period and facilitating the development of an adequate immune response after vaccination. Anaferon for children also demonstrated a good safety profile. We described the schemes of ARVI/influenza prevention: 1 tablet a day for 2–4 weeks before vaccination with possible continuation after vaccination for up to 3 months, depending on the clinical situation during the development of active immunity. The results of RCTs and many years of experience allow us to recommend Anaferon for children combination with specific immunoprophylaxis to optimize the vaccination campaign, especially in children with low resistance to infections. It is particularly important during the pandemic of new coronavirus infection. Key words: vaccination, Anaferon for children, prevention, acute respiratory viral infections
Features of innate and adaptive immunity for infections with rna-containing respiratory viruses
Authors:   Academician N.F.Gamaleya National Research Center for Epidemiology and Microbiology, Moscow, Russian Federation, Morozovа O.V. ,   Federal Research Clinical Center of Physico-Chemical Medicine of the Federal Medical Biological Agency, Moscow, Russian Federation, Ospelnikova T.P. ,   Academician N.F.Gamaleya National Research Center for Epidemiology and Microbiology, Moscow, Russian Federation,   I.I.Mechnikov Research Institute of Vaccines and Sera, Moscow, Russian Federation, Leonova A.Yu. ,   I.I.Mechnikov Research Institute of Vaccines and Sera, Moscow, Russian Federation, Svitich O.A. ,   I.I.Mechnikov Research Institute of Vaccines and Sera, Moscow, Russian Federation
Published: April 2022

During respiratory infections caused by RNA-containing viruses, double-stranded (ds) replicative forms bind with specific receptors in the endosomes and cytosol of infected cells. Therefore, the induction of gene expression of early cytokines occurs faster and more efficiently dsRNA. Induction of innate and specific adaptive immunity usually provides complete eradication of extracellular virions and infected cells without chronic infection and risk of recombination between viral RNA and host cell chromosomes due to absence of DNA copies of the virus genomes. However, this increases the risk of a cytokine storm with pathological disorders of defense systems. Mutual adaptation of viruses and their hosts includes interaction of viral antigens with host cytokines or corresponding receptors that results in disturbances of the fist line of host defense and infection progression. Key words: innate immunity, adaptive immunity, cytokines, interferons, RNA-containing viruses, influenza virus, coronavirus SARS-CoV-2
COVID-19 pandemic: a new round of antibiotic resistance
Authors:   Central Research Institute of Epidemiology of the Federal Service on Customers' Rights Protection and Human Well-being Surveillance, Moscow, Russian Federation, Akimkin V.G. , Tutelyan A.V. ,   Central Research Institute of Epidemiology of the Federal Service on Customers' Rights Protection and Human Well-being Surveillance, Moscow, Russian Federation, Shulakova N.I. ,   Central Research Institute of Epidemiology of the Federal Service on Customers' Rights Protection and Human Well-being Surveillance, Moscow, Russian Federation, Voronin E.M. ,   Central Research Institute of Epidemiology of the Federal Service on Customers' Rights Protection and Human Well-being Surveillance, Moscow, Russian Federation
Published: April 2022

In this article, we analyzed the problems associated with increasing antibiotic resistance, irrational use of antibiotics, and inadequate demand for them during the COVID-19 pandemic. Objective. Using the method of digital epidemiology, we analyzed the dynamics of the frequency of a specific request for antibiotics in pharmacies and hospitals. We used open data from Yandex (Wordstat.Yandex) and Google (Google Trends) collected on weekly basis for the Russian Federation. Results. The World Health Organization reports a growing problem of antibiotic misuse by some individuals and healthcare institutions during the COVID-19 pandemic. Extensive irrational use of antibiotics causes the development of antibiotic resistance by many microorganisms, including those circulating in hospitals (for example, ESKAPE group). Moreover, COVID-19 has led to an exponential increase in the use of biocides worldwide, potentially resulting in additional indirect pressure promoting the selection of antibiotic-resistant strains. The pandemic in Russia was marked by a significant increase in antibiotic sales in pharmacies (including systemic antibacterial agents) and purchases by healthcare institutions. Conclusion. Our findings demonstrate that the rapid spread of COVID-19 was associated with extensive consumption of antibiotics, which resulted in growing antibacterial resistance (number of circulating drug-resistant strains) and posed a threat to the national security. The COVID-19 necessitates the discovery of new effective treatments for this infection, as well as rational use of antimicrobial drugs. The implementation of surveillance of antibiotic consumption will help to identify changing trends in their use, combine efforts to solve problems related to antibiotics and drug resistance, and to ensure rational use of antimicrobials. Key words: antibiotics, antibiotic resistance, pandemic, COVID-19, digital epidemiology