Objective. To compare orthostatic heart rate variability (HRV) parameters in elite and junior-ranked cross-country skiers and to assess their dynamics during enforced detraining.
Material and methods. Fifteen ortho-HRV parameters were analysed in elite cross-country skiers of the Republic of Tatarstan (ECST) and juniorranked skiers (JCST) over a 6-month preparatory period. Additionally, ortho-HRV dynamics were assessed in elite skier K.D. during 7 months of enforced training cessation.
Results. In ECST, medians of 9 HRV parameters (TP, AMHF, AMVLF, AMLF, RRNN, pNN50%, RMSSD, SDNN, MxDMn) were higher, and HR and SI were lower than in JCST; HF%, VLF%, LF%, and AMLF/AMHF did not differ. Following detraining, K.D. demonstrated progressive decline of 12 ortho-HRV parameters to non-athlete levels with concurrent increases in LF%, HR, and SI, while partial preservation of elevated non-neuronal acetylcholine synthesis was suggested by residual HRV signatures.
Conclusion. Elite cross-country skiers exhibit higher parasympathetic autonomic nervous system activity and presumably greater non-neuronal acetylcholine synthesis. Athletic bradycardia regresses substantially faster (within months of detraining) than it develops, which requires 13–20 years of continuous high-volume training.

Relevance. In today's world, especially in the context of urbanization, people are increasingly susceptible to stress and associated cognitive and psycho-emotional impairments.In this regard, the search for agents aimed at adapting the nervous system to stress is becoming promising, among which antidepressants.
The aim of this study was to study the characteristics of the psycho-emotional sphere of animals in model experiments using antidepressants under stressful conditions.
Materials and methods. The study was conducted on nonlinear rats of both sexes. Two groups of animals were formed: the first, a control group (n=6), did not receive any injections; the second, an experimental group (n=8), received subcutaneous injections of fluoxetine at a dose of 10 mg/kg from days 1 to 14 of life. On the 26th day of postnatal ontogenesis, animals from both groups were tested in a black-and-white chamber, and on the 43rd day, in an open-field test. From days 44 to 51 of life, all animals were exposed to continuous light (300 lux) – a model of chronic light stress – after which they were retested in the black-and-white chamber and open-field test. The obtained data were processed using the SigmaPlot12.0 statistical program.
Results. Fluoxetine administration significantly activated the animals' motor behavior and reduced anxiety in the open-field test. Administration of fluoxetine leads to a statistically significant reduction in the time spent by animals in the dark arms of the field in the black-and-white chamber test. In the presence of fluoxetine, the number of transitions between the dark and light arms of the field increased after light exposure, which also indicates a decrease in animal anxiety.
Conclusion. This study demonstrates that fluoxetine have a significant effect on the psycho-emotional state of animals in model experiments, including under stressful conditions caused by chronic light exposure.

Purpose: the aim of the study was to study the content of TBА-reacting substrates in blood plasma and testicular tissues of rats under gamma irradiation conditions.
Materials and methods. In the blood plasma and testicular tissues of male Wistar rats, the concentration of TBАRS was determined by the (Ohkawa) method for3,10 and 40 days after total gamma radiation at a dose of 1.0Gy.
Results. It was found that on three days after gamma irradiation, the content of TBАRS in blood plasma and testicular tissues increased by 91.2% (p<0.05) and 81.6% (p<0.05), respectively, compared with the control. After ten days of follow-up, the increase in TBАRS content reached 232.1% (p<0.05) in blood plasma and 295.9% (p<0.01) in testicular tissues. By forty days after irradiation, the concentrations of TBАRS were 159.3% (p<0.01) and 208.2% (p<0.05) in blood plasma and testicular tissues, respectively.
Conclusion. An increase in the content of TBАRS in blood plasma and testicular tissues in irradiated rats forty days later additionally and clearly confirms the prolonged activation of lipid peroxidation (LPO) processes, which are considered a cause of numerous diseases of the reproductive system in men.

Background. The most complete characterization of any physiological process can only be achieved by considering its changes throughout the day. Misalignment of the biological rhythms of system and organ function can be a cause of pathologies.
Objective of this study: to study the dynamics of changes in some parameters of external respiration in students during the day.
Subject and methods. The study involved 260 male and female students, with an average age of 19 to 22. Respiratory parameters were recorded using a KM-AR01 "Diamant" spirograph (Russia). The following parameters were analyzed: vital capacity of the lungs, reserve volumes of inspiration and expiration, tidal volume, minute ventilation of the lungs, and inspiratory flow rate. External respiration parameters were recorded three times a day: in the morning from 7:30 to 9:00 a.m., in the afternoon from 1:00 p.m. to 2:30 p.m., and in the evening from 6:00 p.m. to 7:30 p.m. For statistical analysis of the obtained data, the SigmaРlot 12.0 software package was used, and the Shapiro-Wilk and Wilcoxon Signed Rank Tests were applied.
Results. Analysis of the obtained data revealed fluctuations in individual external respiration parameters throughout the day, with an acrophase for all parameters occurring in the evening.
Conclusion. The study demonstrates clear circadian dynamics in the studied respiratory parameters.

Introduction. Community-acquired pneumococcal pneumonia is characterized by a severe course in patients with metabolic syndrome (MetS); however, the influence of various combinations of its components remains poorly understood. This study performed stratification of patients according to the component composition of MetS with an assessment of markers of systemic inflammation and endotoxemia.
Aim. To evaluate the features of the systemic inflammatory response in patients with pneumococcal pneumonia depending on the criteria of metabolic syndrome, with assessment of the leukocyte index of intoxication and markers of inflammation.
Materials and methods. A prospective comparative cohort study included 38 patients with pneumococcal pneumonia, stratified into 3 groups according to the criteria for metabolic syndrome (IDF, 2005). Blood sampling was performed within the first 24 hours of hospitalization, followed by determination of endotoxin level (LAL test), markers of inflammation (interleukin-6, tumor necrosis factor-alpha, C-reactive protein, procalcitonin), immune status (CD4+/CD8, lymphocyte subpopulations), and calculation of the leukocyte index of intoxication.
Results. The most pronounced disturbances in immune status and endotoxemia indicators were registered in patients of group A (abdominal obesity + type 2 diabetes + arterial hypertension + dyslipidemia), where an increase in endotoxemia level to 1.46 [1.29; 1.55] EU/ml, leukocytosis (14.8±1.3 ×10⁹/L), neutrophilia (81.8±3.1%), lymphopenia (14.8±2.5%), and an increase in the leukocyte index of intoxication to 9.4±1.4 were noted. An imbalance in the immunoregulatory index was revealed due to a decrease in CD4+ lymphocytes (33.8±2.2%) with a simultaneous increase in CD8+ cells (30.6±2.2%), indicating impaired regulation of the immune response. Indicators of patients in group B (abdominal obesity + type 2 diabetes + reduced high-density lipoprotein cholesterol (HDL-C) level) and group C (abdominal obesity + arterial hypertension + hypertriglyceridemia) demonstrated statistically significantly less pronounced changes in both immunological parameters and endotoxemia level.
Conclusion. The most unfavorable profile, characterized by the maximum level of endotoxemia, hyperactivation of the cytokine cascade (interleukin-6, tumor necrosis factor-α, C-reactive protein, procalcitonin), and signs of immune dysregulation (decreased CD4+/CD8+ ratio, high leukocyte index of intoxication), was formed in patients of group A, which combines abdominal obesity, type 2 diabetes, arterial hypertension, and dyslipidemia.

Relevance. Clinical studies show that women with low vitamin D levels are more likely to experience early menopause. The combination of early menopause and vitamin D deficiency increases the risks of cardiovascular disease, osteoporosis, and metabolic syndrome.
The aim of the study was to study the effect of vitamin D deficiency on the development of cardiovascular pathology in postmenopausal women.
Materials and methods. The study involved 43 women with a decrease in estradiol levels below 73 pmol/l and an increase in FSH levels above 30 IU/l and the absence of a menstrual cycle for at least 12 months. The first group (n-20) included patients with vitamin D deficiency. The second group (n-23) consisted of patients of the same age with adequate vitamin D levels. The levels of IL-6, brain natriuretic peptide, D–dimer, lipidogram, fasting glycemia and glycated hemoglobin were studied in patients of both groups. All patients underwent EchoCG and daily blood pressure monitoring.
Results. Postmenopausal women with vitamin D deficiency have higher levels of proatherogenic plasma lipid profile fractions, IL-6 levels, brain natriuretic peptide, and D-dimer. Obesity, type 2 diabetes mellitus, and hypertension are more common.
Conclusions. The study demonstrated the negative impact of vitamin D deficiency on cardiovascular risks in postmenopausal women. This highlights the need for regular laboratory monitoring of vitamin D levels in clinical practice as part of an integrated approach to the prevention and management of cardiovascular health in peri- and postmenopausal women.

Objective. To evaluate the efficacy and safety of pencil beam scanning (PBS) proton therapy in the treatment of skull base chordomas at the clinical facility of the Federal Scientific and Clinical Center of Medical Radiology and Oncology of FMBA of Russia.
Materials and Methods. The study included 11 patients with skull base chordomas who underwent proton therapy between 2021 and 2022. All patients had prior surgical resection (R0 – 9.09%, R1 – 18.18%, R2 – 72.72%). Radiotherapy was delivered using PBS technique at a mean dose of 70.0±4 Gy (RBE). Median follow-up was 21 months. Local control, overall survival, and toxicity (CTCAE v.5.0) were assessed.
Results. The 1- and 2-year survival rates were 100%, and the 3-year survival rate was 89.9% (one death from myocardial infarction). Local recurrences occurred in 2 patients (18.1%) at 32 and 36 months, both with initially large tumor volumes (GTV > 62 cm³). Acute toxicity included grade 1–2 keratitis (45.5%). Late grade 3 toxicity (optic neuropathy) was observed in 1 patient (9%). No grade 4–5 toxicity was reported.
Conclusion. Proton therapy with PBS technique is a safe and effective treatment modality for skull base chordomas and should be recommended for routine clinical practice.

Relevance. This study is the first in the world to use quantitative T2 mapping to objectively assess the ability of low-dose radiation therapy (LDRT) to directly influence the biochemical structure of articular cartilage in osteoarthritis.
Objective: To retrospectively assess changes in the structural and functional state of cartilage using T2 mapping one year after a course of lowdose radiation therapy (LDRT) in patients with knee osteoarthritis (OA).
Materials and Methods. The analysis included data from 148 patients with knee OA (radiographic stages 0–2 according to the Kellgren-Lawrence classification) from a randomized study. Patients in the control group (n=73) received standard therapy with SYSADOA (glucosamine + chondroitin), while those in the main group (n=75) received the same therapy plus LDRT (total dose 4.5 Gy in 10 fractions). Patients in both groups received nonsteroidal anti-inflammatory drugs (NSAIDs) on demand for pain relief.MRI with T2 mapping (1.5 T) was performed before and 12 months after treatment. A quantitative comparison of T2 relaxation time in cartilage segments was conducted according to the WORMS protocol. Statistical analysis utilized the Mann-Whitney U test.
Results. The LDRT group demonstrated a significantly smaller increase in T2 relaxation time after one year compared to the control group, indicating slowed cartilage degradation. For example, in the lateral facet of the patella, ΔT2 was 1.9 ms [1.1; 3.2] versus 12.5 ms [12.1; 12.9] in the SYSADOA-only group (p<0.001). Similar significant differences were found in the lateral tibial plateau (ΔT2 1.7 ms vs. 2.9 ms) and the medial femoral condyle (ΔT2 3.9 ms vs. 6.8 ms).
Conclusion. The addition of low-dose radiation therapy to standard OA treatment significantly slows the progression of degenerative changes in articular cartilage, as objectively confirmed by quantitative T2 relaxation dynamics. LDRT demonstrates a protective effect, potentially by modulating inflammation and creating conditions for the stabilization of the cartilage matrix.

Objective. To systematize and summarize current data on the role of nondiphtherial corynebacteria (Corynebacterium spp.) in the development of purulent-inflammatory infections of various anatomic sites and to review current methods of their laboratory diagnosis.
Materials and Methods. Analysis of Russian and international publications devoted to taxonomy, biological properties, pathogenetic potential, and antibiotic resistance of microorganisms of the genus Corynebacterium was performed. Current methods of species identification are reviewed: bacteriological, biochemical (API Coryne), molecular genetic (16S rRNA gene sequencing), and mass spectrometric (MALDI-ToF-MS).
Results. More than 53 species of corynebacteria have clinical significance. The most frequently isolated from infectious foci are C. striatum, C. jeikeium, C. amycolatum, C. simulans, C. aurimucosum, and several other species. They cause skin lesions (erythrasma, pitted keratolysis), infect burn wounds, cause pneumonia, endocarditis, urinary tract infections, osteomyelitis, and sepsis with mortality rates up to 30%. Several species–C. tuberculostearicum, C. kroppenstedii, C. simulans–are associated with chronic inflammatory and oncologic skin lesions. Many clinically significant species possess multidrug resistance; vancomycin and linezolid remain the antibiotics of choice.
Conclusion. Nondiphtherial corynebacteria are significant opportunistic microorganisms capable of causing severe infections in immunocompromised patients. Timely species identification using modern methods (MALDI-ToF-MS, 16S rRNA sequencing) and determination of antibiotic susceptibility are necessary to improve treatment effectiveness.

This review analyzes the fundamental mechanisms of neurovascular unit (NVU) degradation and restoration under conditions of acute cerebral blood flow deficiency and subsequent reperfusion. The physiological basis of cellular disorganization is examined, with lipid peroxidation acting as the leading factor in neuronal membrane destruction. Particular attention is paid to the role of the mitochondrial network as a central regulator of NVU cell survival. The paper describes in detail current understanding of the structural and functional integrity of the NVU and the molecular mechanisms of its damage. Central to this is the analysis of the PGC-1α regulatory axis as a key factor in mitochondrial biogenesis and antioxidant defense. The authors systematize data on mitochondrial dynamics (fusion), selective autophagy (mitophagy), and the role of the mitochondrial proliferator-activated pore (mPTP) in determining cell fate in the post-perfusion period. The final section of the review discusses promising strategies for pharmacological correction: from the reduction of oxidative stress and neuroinflammation to the induction of organelle biogenesis. The therapeutic potential of mitochondrial modulation as an effective method for restoring the neurovascular unit after ischemic injury is substantiated.

Aim: to determine the clinical and diagnostic value of semi-automated assessment of total and local brain atrophy parameters using accessible segmentation tools for the comparative analysis of neurodegenerative changes in patients with various multiple sclerosis (MS) phenotypes in association with clinical and historical data.
Material and methods. A retrospective analysis of data from 135 patients was conducted. Clinical indicators (EDSS, disease duration, age) and MR-morphometric parameters (Evans, Schlattenberg, and Akimov indices, the ratio of cerebrospinal fluid (CSF) volume to brain volume, and the MTA scale) were evaluated. Non-parametric statistical methods were employed, including the Kruskal-Wallis test and Spearman's rank correlation coefficient.
Results. A statistically significant increase in the proportion of CSF spaces relative to brain volume was identified as disease severity progressed: from 0.11 (0.09; 0.15) in RRMS to 0.25 (0.21; 0.29) in PPMS (p < 0.001). Linear indices (Schlattenberg and Akimov indices) demonstrated high sensitivity to the disease phenotype (p < 0.001). A correlation between EDSS and brain atrophy was established only within the RRMS group (p = 0.046).
Conclusion. The ratio of CSF volume to brain volume is the most stable marker of neurodegeneration, allowing for the differentiation of MS phenotypes.

Aim. To systematize and comparatively analyse Russian patent developments of 1996–2024 concerning the use of acupuncture, needle reflexotherapy (NRT) and related techniques in patients with ischemic stroke (IS), with particular emphasis on methods applicable in the subacute phase (≥21 days post-onset).
Material and methods. A search was performed in Rospatent/FIPS, Google Patents, Espacenet, and WIPO PATENTSCOPE databases using Boolean operators and the keywords "acupuncture", "reflexotherapy", "electroacupuncture", "stroke", "post-stroke", "rehabilitation" (coverage through May 2026). Inclusion criteria: Russian Federation patent with an acupuncture component for cerebral stroke. Nine core patents and five adjacent patents on competing non-pharmacological methods were identified and analysed.
Results. Combined protocols predominate, integrating body acupuncture with scalp acupuncture, auriculotherapy, electrostimulation (DENS), magneto-laser therapy or pharmacopuncture. The school of E.E. Molchanova (Amur State Medical Academy), represented by patents RU2531693C1 (2014) and RU2669025C1 (2018), shows the highest level of methodological detail. Although most patents are formally designated for the "acute period", the described 10–15-session daily courses in practice cover the subacute phase. Core acupoints identified: LI4, LI11, TE5, ST36, GB34, SP6. After 2018 a clear shift in patenting activity towards high-technology neurorehabilitation methods is observed.
Conclusion. The Russian patent corpus on acupuncture for IS is methodologically rigorous and clinically relevant. Priority directions for further inventive activity include dedicated subacute-phase protocols, domestic electroacupuncture devices with verified stimulation parameters, objective efficacy assessment methods using neuroimaging biomarkers, and international patent filing of the most promising Russian developments.

Background. Acute gastric dilatation (AGD) is a life-threatening condition that has been studied for nearly two centuries, yet it is frequently diagnosed with delay due to the subtlety of early clinical signs and their frequent misattribution to postoperative status.
Aim. To summarize the historical evolution of concepts regarding the etiopathogenesis of AGD and to analyze the authors' own clinical observations in order to clarify current diagnostic and therapeutic approaches.
Material and Methods. Domestic and international publications from 1842 to 2023 were analyzed (eLibrary, PubMed, Cyberleninka, and JAMA Network databases), including the historical works of Rokitansky, Mondor, and Samarin. Three of the authors' own clinical cases illustrating different clinical courses of AGD are presented.
Results. Three historical stages in understanding AGD etiology were identified: the anatomical stage (mechanical duodenal compression, per Rokitansky), the reflex stage (neurovegetative paralysis of the intestinal wall, per Mondor), and the systemic stage (multiple organ dysfunction, per Zilber). Contemporary AGD etiology is shown to be multifactorial, encompassing mechanical, neurogenic, metabolic, and alimentary causes. The diagnostic value of CT for detecting early signs of gastric wall ischemia (pneumatosis, hepatic portal venous gas) is demonstrated, and treatment strategy is substantiated — ranging from nasogastric decompression with a large-bore tube to emergency surgical intervention.
Conclusion. Despite advances in imaging, clinical vigilance and early gastric decompression remain the cornerstone of timely AGD diagnosis. Establishing an international registry of clinical cases could substantially expand knowledge of this condition through systematic documentation.

Introduction. Cardiac conduction disorders, particularly heart blocks, are frequently underdiagnosed in many resource-limited health systems despite being significant contributors to morbidity and mortality. Accurate interpretation of electrocardiograms (ECGs) is central to early detection, yet many frontline healthcare providers continue to experience challenges in identifying and classifying heart block patterns.
Materials and Methods. The study adopted a mixed-methods quasi-experimental research design. It combined a cross-sectional baseline assessment with a pre-test intervention approach to evaluate changes in healthcare providers’ competence in ECG-based heart block risk prediction.
Results. The analysis was conducted to determine whether differences in pre-intervention competence were associated with respondents’ professional category and years of experience. The overall fit is indicated by the results of corrected model which was statistically significant (F (13;114) = 8.975, p<0.001), indicating that the independent variables included in the model significantly explained variation in respondents’ baseline competence scores.
Conclusions. There were significant differences in baseline competence among respondents based on their professional category and years of experience, suggesting that both factors play an important role in shaping initial competence levels prior to the intervention.

Background. Medullary thyroid carcinoma is a relatively rare but clinically significant malignant tumor characterized by marked morphological heterogeneity and variability in clinical behavior. In the context of updated classifications of thyroid tumors and the introduction of modern tumor grading systems, the systematization of morphological, immunohistochemical, and molecular genetic criteria for diagnosis and prognostic stratification has become particularly relevant.
Objective. To analyze current concepts regarding the characteristics of medullary thyroid carcinoma, criteria for prognostic stratification, and to identify current challenges in its diagnosis.
Materials and methods. This review was conducted as a systematic analysis of domestic and international scientific literature on medullary thyroid carcinoma. Publications were searched in the eLIBRARY, PubMed, Scopus, and Web of Science databases for the period from 2000 to 2026 using the following keywords: “medullary thyroid carcinoma,” “C-cells,” “morphology,” “immunohistochemistry,” “calcitonin,” “neuroendocrine tumors,” “RET mutations,” “tumor grading,” and their combinations. Additionally, publications from 1970 to 2026 were analyzed using similar search strategies to provide a historical background. Inclusion criteria comprised original clinical studies, meta-analyses, systematic reviews, and selected case reports containing data on clinical, laboratory, morphological, and molecular genetic characteristics of medullary thyroid carcinoma. Publications without full-text access and duplicate studies were excluded. Study selection was performed in two stages: initial screening of titles and ABSTRACTs followed by full-text review. Data analysis was carried out using qualitative synthesis.
Results. Medullary thyroid carcinoma is characterized by heterogeneity in cellular composition and architectural patterns, necessitating a comprehensive diagnostic approach with mandatory use of immunohistochemical and molecular genetic methods. The application of an extended immunohistochemical panel, including calcitonin, CEA, neuroendocrine markers, and TTF-1, is essential for diagnostic verification. Additional prognostic value is associated with the identification of high-grade features, with particular importance attributed to the presence of tumor necrosis.
Conclusion. The optimal approach to the diagnosis and prognostic assessment of medullary thyroid carcinoma should be integrative, incorporating morphological evaluation, an extended immunohistochemical panel, and molecular genetic methods. Implementation of such a comprehensive strategy improves diagnostic accuracy, enables a more objective assessment of tumor aggressiveness, and provides a platform for deeper investigation of medullary thyroid carcinoma in future studies based on representative cohorts.

Background. Anaphylactic shock in obstetrics is a rare but potentially life-threatening cause of maternal and perinatal morbidity and mortality, largely determined by the specific immunological alterations occurring during pregnancy.
Case presentation. We report a case of anaphylactic shock developing after administration of cefotaxime as preoperative antibiotic prophylaxis, resulting in a fatal maternal outcome. The causative agent was a cephalosporin capable of inducing cross-allergic reactions with penicillins.
Conclusion. Thorough allergological history-taking and careful assessment of comorbidities in pregnant patients may not entirely prevent anaphylaxis, but can substantially reduce its severity and consequences.

Background. MELAS syndrome is a maternally inherited mitochondrial disorder whose cardinal triad — lactic acidosis, seizures, and stroke-like episodes — frequently mimics acute ischaemic stroke. Late, adult-onset presentations are easily missed, delaying disease-specific therapy.
Aim. Through a single clinical case, to outline the diagnostic pathway from a presumptive ischaemic stroke to confirmed mitochondrial encephalomyopathy in a 44-year-old woman, and to map the neuroimaging, neurophysiological, and morphological steps that anchor the diagnosis of MELAS.
Case presentation. A 44-year-old woman was admitted with a working diagnosis of ischaemic stroke after presenting with an upper-left quadrantanopia, blurred near-vision, impaired attention and memory, and a sense of head heaviness. Brain MRI showed cortical laminar necrosis in the right occipital lobe with the subcortical white matter spared — a pattern uncharacteristic of arterial-territory infarction. Lactate dehydrogenase was elevated (450.83 U/L); blood lactate sat at the upper reference limit. Needle EMG documented a reduction in mean motor-unit potential duration. Biopsy of the vastus lateralis muscle revealed fragmentary atrophy, coagulation necrosis of individual fibres, and the ragged-red-fibre pattern of mitochondrial myopathy. Disease-modifying therapy was started — L-arginine, coenzyme Q10, succinic acid, and riboflavin.
Conclusion. Adult-onset MELAS demands deliberate vigilance from the neurologist. Sparing of the subcortical white matter beneath a zone of cortical laminar necrosis, a lesion that ignores arterial territories, a myopathic EMG, and ragged-red fibres on biopsy form a self-reinforcing constellation that supports the diagnosis ahead of molecular confirmation and lets disease-specific treatment begin without delay.

Introduction. The management strategies for patients with patellofemoral osteoarthritis remain controversial, with surgical treatment options being actively debated in current literature. Current guidelines indicate knee arthroplasty for cases with full-thickness cartilage defects and subchondral bone changes. However, at present, knee arthroplasty does not always meet all the patient's demands regarding physical activity, especially in young patients. Addressing this issue could potentially improve quality of life for young patients with isolated patellofemoral joint osteoarthritis.
The purpose to evaluate short-term outcomes in a patient with patellofemoral osteoarthritis following arthroscopic marginal contouring resection of the patella with refixation of the medial quadriceps tendon complex.
Materials and methods. A 41-year-old male patient presented with limited range of motion and severe knee pain. Medical history included recurrent patellar dislocations and two previous patellar stabilization procedures.
Results. At one-year follow-up, the patient reported complete resolution of pain and full restoration of knee mobility.
Discussion. The optimal management of young patients with patellofemoral osteoarthritis remains unresolved. The efficacy of joint-preserving surgical techniques requires further scientific evaluation with larger patient cohorts.
Conclusion. Arthroscopic marginal contouring resection of the patella combined with medial quadriceps tendon realignment can yield satisfactory functional outcomes in advanced-stage patellofemoral osteoarthritis.

Background. Bezoars, as a cause of high gastrointestinal obstruction, occur in 0.4–4% of cases, with phytobezoars being the most common type. In an intact stomach, phytobezoar formation is practically impossible due to hydrolytic breakdown of plant fibers by hydrochloric acid and pepsin. After gastric resection, a complex of pathophysiological changes develops (hypochlorhydria, impaired motility, loss of the pyloric barrier) that predisposes to bezoar formation.
Aim. To present a clinical case of diospyrobezoar in a patient with a history of gastric resection and to analyze the pathogenetic mechanisms underlying its formation.
Materials and Methods. A 71-year-old female patient with a history of two-thirds gastric resection with a Billroth-I gastroduodenal anastomosis was admitted emergently with signs of high gastrointestinal obstruction (nausea, vomiting after food and water intake, absence of stool). Historytaking revealed persimmon consumption 3 days before symptom onset. Esophagogastroduodenoscopy (EGD) with an attempted endoscopic removal of the bezoar was performed, followed by surgical intervention after the endoscopic approach failed.
Results. EGD revealed a dense, stone-hard phytobezoar occupying the gastric stump lumen with extension into the duodenum; endoscopic removal attempts were unsuccessful. A midline laparotomy and gastrotomy were performed, with evacuation of a foreign body measuring 10.0×5.0 cm. The postoperative course was uneventful, and the patient was discharged in satisfactory condition on postoperative day 14.
Conclusion. Patients with a history of gastric resection constitute a high-risk group for bezoar formation due to impaired hydrolysis and mechanical processing of dietary fiber. Endoscopic removal of large, dense bezoars is not always effective, necessitating timely conversion to surgical treatment.

The manuscript presents an analysis of the current 2024 clinical guidelines of the British Society of Echocardiography for assessing left ventricular diastolic function, based on ejection fraction and the presence of cardiovascular diseases. It compares the new approaches and methods described in the document with clinical guidelines and consensus publications from the European Society of Cardiology and the European Association of Cardiovascular Imaging. Practical recommendations for the application of the proposed new algorithms and the development of a final echocardiography protocol are provided.

Background. Hypertrophic cardiomyopathy (HCM) is a genetically determined disease characterized by left ventricular hypertrophy of various localizations, including asymmetric septal, concentric, and apical morphotypes, myocardial fibrosis, myofibrillar disorganization, and predisposition to sudden cardiac death. Feature Tracking cardiac MRI allows quantitative assessment of myocardial strain regardless of HCM morphotype; however, comprehensive analysis of synchronization parameters (time-to-peak, TTP) and strain rate in Russian patient cohorts remains limited.
Purpose. To determine the characteristics of global and segmental myocardial deformation, temporal parameters, and strain rate of the left ventricle in patients with HCM using cardiac MRI with Feature Tracking technology.
Materials and Methods. Analysis included 74 patients with confirmed HCM diagnosis who underwent 3.0T cardiac MRI. Using CVI 42 software, the following parameters were determined: global longitudinal strain (GLS), circumferential strain (GCS), and radial strain (GRS) in percentages; time-to-peak (TTP) parameters for each deformation direction; peak systolic strain rate. Comparison was performed with published reference values for healthy volunteers at 3.0T. Patient risk stratification was performed based on GLS values.
Results. GLS was significantly reduced (–7.22±4.43% vs normal –16.9±1.8%, p<0.001), GCS was moderately reduced (–16.21±3.16% vs normal –19.2±2.1%, p<0.001), and GRS was compensatorily elevated (45.52±21.60% vs normal 34.2±6.1%, p<0.001). TTP dispersion was 80.9±21.9 ms, exceeding normal values 1.6-fold, indicating pronounced mechanical dyssynchrony (88.4% of patients with SD > 50 ms). Risk stratification revealed that 60% of patients demonstrated critically reduced GLS values (> –8.35%), which is associated with poor prognosis in recent studies. Identification of such severe dysfunction suggests the need for comprehensive risk stratification for sudden cardiac death, as outlined in the 2023 ESC guidelines.
Conclusions. Feature Tracking 3.0T cardiac MRI reveals a characteristic deformation pattern in HCM with pronounced GLS reduction, moderate GCS reduction, and compensatory GRS elevation. Pronounced mechanical dyssynchrony may serve as an arrhythmia risk marker. The majority of this cohort demonstrates critical GLS values requiring careful sudden cardiac death risk stratification.

Introduction. Chronic insomnia is a common sleep disorder, affecting approximately 10–15% of adults. It is associated with reduced quality of life, cognitive disturbances, and decreased risk of somatic diseases. Functional magnetic resonance imaging (fMRI) allows to assess resting-state neural activity and analyze major brain networks interactions, including sensorimotor network (SMN), visual network (VN), and frontoparietal network (FPN). Previous international studies demonstrated that chronic insomnia involves alterations in both intra- and inter-network connectivity, characterized by increased default mode network activity and reduced frontoparietal integration. However, similar findings in Russian populations are scarce, and associations between functional connectivity measures and objective polysomnographic (PSG) sleep parameters remain insufficiently investigated.
The study aimed to identify major resting-state functional networks in patients with chronic insomnia, assess internetwork connectivity and its correlation with objective sleep parameters.
Materials and methods. The study included 51 patients with clinically confirmed chronic insomnia and 34 healthy volunteers. All participants underwent examination at the Almazov National Medical Research Centre, Ministry of Health of the Russian Federation. Polysomnography was performed using the Embla N7000 system (Natus, USA) and Somnologica Studio software in accordance with the standard protocol. Magnetic resonance imaging was conducted using Magnetom Trio A Tim scanner (Siemens, Germany) with a magnetic field strength of 3.0 T. The protocol comprised a structural T1-MPRAGE sequence and a functional EPI-BOLD sequence (resting state). Data preprocessing included motion correction, slice-timing adjustment, normalization, and spatial smoothing. Independent component analysis (ICA) was performed using SPM12, CONN Toolbox, and DPABI. Statistical analysis was conducted using two-sample t-tests with false discovery rate (FDR) correction for multiple comparisons (p<0.05).
Discussion. Independent component analysis revealed altered functional organization of the sensorimotor, visual, and frontoparietal networks in patients with chronic insomnia. In individuals with disrupted sleep architecture, reduced connectivity between the sensorimotor network and temporal associative regions indicated incomplete deactivation of sensory circuits during the transition to sleep. Decreased connectivity of the visual network with cerebellar and parietotemporal regions suggested impaired sensory inhibition and persistent activation of visual pathways. In patients with reduced sleep quality and prolonged sleep latency, weakened connectivity of the frontoparietal network with frontal and parietotemporal regions reflected impaired cognitive inhibition. Obtained data support the hyperarousal model of chronic insomnia, characterized by sustained activation of executive and sensory networks even during rest.
Conclusion. Patients with chronic insomnia showed altered functional organization of the sensorimotor, visual, and frontoparietal networks, characterized by reduced connectivity with associative and executive brain regions. These changes indicate impaired sensory and cognitive deactivation processes necessary for the transition to sleep and align with the hyperarousal model of insomnia. The findings enhance understanding of neurophysiological mechanisms of sleep disorders and may support the identification of objective MRI markers of sleep-wake regulation disturbances.