This article examines the role of traumatic brain injury as a trigger for the development of neurodegenerative changes. Dysfunction of neurovascular units and disruption of the functional and compensatory capabilities of blood flow are addressed. The importance of microhemorrhages in the acute period of traumatic brain injury (TBI) and the formation of neuroinflammation is emphasized. Mitochondrial dysfunction has been noted to play a role in increasing the risk of developing Alzheimer’s disease (AD) in patients with TBI. Decreased expression of tight junction proteins leads to increased permeability of the blood–brain barrier (BBB). TBI, provoking endothelial dysfunction, contributes to disrupting β-amyloid and tau protein metabolism and aggravating vascular damage, which results in a vicious circle which can lead to the development of AD and dementia. Changes in the cerebral arteries leading to impairment of interstitial fluid transport are seen as an important part of the “amyloid cascade” on the background of genetically mediated disorders of glial membranes associated with defects in aquaporin-4. The TBI-triggered reaction cascade includes all the main elements of the pathogenesis of AD: disturbances in energy metabolism, microcirculation, and clearance of metabolic products, which leads to the accumulation of amyloid protein in the brain with the subsequent development of tauopathy. Cerebrolysin modulates the permeability of the BBB, blocking the development of neuroinflammation; it reduces the accumulation of pathological forms of proteins and can slow the progression of neurodegeneration.

The incidence of primary brain tumors is increasing worldwide. When assessing the treatment delivered to patients with brain gliomas, their quality of life (QOL) is an essential criterion for consideration. It is necessary to search for and specify the factors, which determine the QOL changes in patients with brain tumors. The QOL indicators for patients with brain gliomas were assessed in terms of the following factors: clinical (presence of epileptic seizures, seizures type and frequency, antiepileptic drug treatment, presence of speech disorders and pareses), demographic (sex), age of diagnosis, social (level of education, employment, marital status), molecular-genetic (presence of IDH1/2 mutation, 1p/19q codeletion), and morphological (malignancy degree, tumor histological characteristics). The QOL of 48 patients with diffuse brain gliomas was tested according to the objectives of the study. The QOLIE-31 questionnaire (version 1.0) indicates that diffuse glioma patients with epilepsy have statistically significant decrease in such QOL spheres as seizures worry (p<0.0001), cognitive functioning (p=0.0043), antiepileptic drug effect (p=0.0002), social functioning (p=0.0029), as well as in the total score (p=0.0053). In addition, such factors as age, gender, tumor malignancy degree, and its histological type have a statistically significant effect on the QOL of patients with diffuse brain gliomas before surgery. Thus, the treatment of patients with diffuse brain gliomas requires a thorough study and a multidisciplinary approach, including such specialists as a neurologist, oncologist, chemotherapist, radiologist, neuropsychologist, and psychiatrist, in addition to a neurosurgeon.

One of the possible measures that can enhance the quality of medical care, reduce the number of adverse outcomes, and also achieve target values for the use of reperfusion methods of treatment for acute ischemic stroke is to improve the system of care for patients with in-hospital ischemic stroke. One type of in-hospital stroke is perioperative stroke that develops during or 30 days after surgery. Since the publication in 2014 of the last fundamental work on the prevention of perioperative stroke, the approaches to primary and secondary prevention, diagnosis, conservative and reperfusion treatment of ischemic stroke have been seriously modified. The numerous changes have created the preconditions for a revision of existing approaches to providing care for patients with perioperative ischemic stroke. In 2021, updated documents from foreign researchers/associations on the perioperative ischemic stroke in non-cardiac and non-neurosurgical patients were published. The second part of our review presents current data on the perioperative antithrombotic prophylaxis, clinical and instrumental diagnosis, treatment and organization of care for perioperative ischemic stroke in this category of patients. The issues of using reperfusion treatment methods in non-cardiac and non-neurosurgical patients with perioperative stroke, such as systemic thrombolytic therapy and endovascular interventions, are discussed in detail, including the world experience of their “offlabel” use.

Justifi cation. Due to the high prevalence of diseases of the visual organs (cataracts, glaucoma, etc.) and the large number of surgical interventions performed annually in elderly and senile people, the prevention of in-hospital ischemic stroke (IHS) is an urgent task.The purpose of the work. To study the risk factors of development, characteristics of care and outcomes of IHS in ophthalmic patients.Material and methods. The study was performed in the period from 01.01.2022 to 31.12.2022 on the basis of ophthalmological departments specializing in the performance of planned vitreoretinal surgical interventions, two large multidisciplinary hospitals in St. Petersburg.Results. It has been established that perioperative ischemic stroke (included in the structure of the IHS) is a rare complication of minimally invasive ophthalmic operations. Its share was 0.07% (n = 5) of the total number of patients who underwent elective ophthalmological intervention during the year; the total share of patients with IHS (taking into account 4 cases of ischemic stroke in the preoperative period) was 0.13%. Most strokes (n = 5; 55.6%) belonged to the cardioembolic subtype, the proportion of using reperfusion techniques was high and amounted to 33.3% (2 endovascular interventions, 1 systemic thrombolysis); the proportion of adverse outcomes was 22.2% (n = 2). A distinctive characteristic of patients with IHS was a combination of high comorbidity with insuffi cient antithrombotic prophylaxis, which consisted in the cancellation of antiplatelet agents and anticoagulants in the preoperative period.Conclusion. Current recommendations on perioperative management of patients indicate the need to continue taking antiplatelet and anticoagulant drugs for most ophthalmic operations, due to the predominance of threats of thromboembolic complications over the risk of retrobulbar bleeding.

The objectives of surgical treatment of patients with diff use brain gliomas include achieving control over epileptic seizures and improving quality of life, in addition to prolonging relapse-free period and life duration. The aim of the research is to study the factors that determine the eff ectiveness of epilepsy surgery in patients with diffuse brain gliomas. Material and methods. The study group comprised 104 patients with diff use brain gliomas, aged 41.21 ± 14.74. Results of author’s research. Clinical, neuroimaging and morphological factors were studied. Of the studied group of 104 patients with diffuse brain gliomas who had been diagnosed with epilepsy prior to surgery, the remission of 6 months after surgery was achieved in 58 (55.77 %) patients and of 12 months in 55 (52.88 %) patients. The development of acute symptomatic epileptic seizures (p = 0.68067) and acute symptomatic status epilepticus (p = 0.41626) in post-operative period do not determine the outcomes of epilepsy surgery. Neither the histological subtype of the diffuse brain gliomas, nor the molecular-genetic factor (IDH1/2 mutation, 1p/19q codeletion) determines the outcomes of epilepsy surgery in this patient category. The group of antiepileptic medications or the medication regimen (monotherapy, two-drug therapy) also does not determine the surgery outcomes. The factors that determine a favorable outcome of surgical treatment for epilepsy in patients with diff use brain gliomas are complete tumor removal and involvement of brain commissures after magnetic resonance imaging before surgery. Conclusion. The effectiveness of epilepsy surgery is determined by the radical removal of the diff use brain glioma, thereby eliminating the glutamate-mediated mechanisms of epileptogenesis.

Clinical guidelines and the order of providing care in acute cerebrovascular accidents (CVA) have been developed for standard clinical situations, primarily for patients admitted to medical institutions in an emergency state. However, there are clinical situations when a generally accepted order of therapeutic and diagnostic measures concerning patients with stroke is unjustified and, on the contrary, its implementation threatens life and health of a patient. These situations include ischemic strokes developing intraoperatively during such endovascular interventions as diagnostic cerebral and coronary angiography and transcutaneous neuro- and cardiovascular surgery. Ischemic cerebral events after diagnostic endovascular procedures are relatively rare complications, but their development can lead to unfavorable consequences. Thus, the rates of transient cerebral circulatory disorders after cerebral angiography, a stroke with a reversible neurological deficit, and an ischemic stroke with a persistent neurological deficit are 2.45 %, 0.3 %, and 1.0 % respectively, while total mortality due to acute cerebrovascular pathology is 0.14 %. The rate of cerebral stroke after coronary angiography and percutaneous coronary interventions is up to 0.4 %. Prevention of neurologic complications in diagnostic and surgical transcutaneous interventions is strongly dependant on their correct technique, rational perioperative antithrombotic therapy, and lesser duration of endovascular operations.

Study objective. To develop knowledge of the epileptic status (ES) in early post-op period in patients with diffuse brain gliomas. Design. Single-centre retrospective study. Materials and methods. The study group included 280 patients with diffuse brain gliomas: 156 males (55.71%) and 124 females (44.29%). The average age of subjects was 45.81 ± 15.90 years. To identify the diffuse glioma sub-type, 118 patients underwent an examination of frequent mutations of genes IDH1 (exon 4) and IDH2 (exon 4) in tumour tissue using a high-resolution analysis of PCR product melting profile and sequencing. Results. ES in early post-op period developed in 3.57% of cases (n = 10) and manifested predominantly with motor symptoms (paroxysmal, myoclonic, focal motor symptoms). Epilepsy diagnosed before surgery was not a risk factor of ES in early post-op period. Awake surgeries, aiming at determination of the functionally significant (verbal, motor) areas of the brain, as well as the use of intraoperative neurophysiological monitoring (direct cortex stimulation during surgery) did not increase the rate of ESs. It has been demonstrated that ES in patients with diffuse brain gliomas can develop after a longer surgery (p = 0.0129) or longer anaesthesia (p = 0.0251). The association between ES in early post-op period and cerebral complications has been reported: in patients with complications, the rate of ESs was 17.07% vs. 1.26% (p < 0.00001). in patients without complications. The rate of early ESs did not drop with preventive antiepilepsy drugs prescribed to patients with diffuse brain gliomas without pre-op epilepsy, as well as with prolonged sedation with propofol and artificial lung ventilation. Conclusion. ES in early post-op period requires separate diagnostic and treatment algorithms. Keywords: diffuse brain gliomas, post-op period, epilepsy, epileptic status, antiepilepsy drugs.

OBJECTIVE:Evaluation of the efficacy and safety of the drug Acatinol Memantine, 20 mg (once daily) in comparison with the drug Acatinol Memantine, 10 mg (twice daily) in patients with moderate to moderate severe vascular dementia. MATERIAL AND METHODS:The study included 130 patients aged 50-85 years of both sexes with instrumentally and clinically confirmed vascular dementia. The patients were randomized into 2 groups. Group I consisted of 65 patients receiving Akatinol Memantine, 20 mg once daily, group II - 65 patients receiving Akatinol Memantine, 10 mg twice daily for 24 weeks. Clinical, parametric and statistical research methods were used. The Alzheimer's disease assessment scale, the cognitive subscale (ADAS-cog), the short mental Status Assessment Scale (MMSE) and the general clinical impression scale for patients condition and illness severity (CGI-C and CGI-S) and the Hamilton Depression Rating scale (HAM-D) were used. Adverse events were collected and analyzed. RESULTS:At week 24, both groups showed statistically significant positive change in ADAS-cog total score: in group I the total score was 27.2±8.76 points (absolute difference from baseline 3.5 points; p<0.01), and in group II - 26.1±7.86 points (absolute difference from baseline 2.5 points; p<0.01) with no statistically significant differences between groups. Evaluation of secondary efficacy criteria (change in ADAS-cog total score at week 12 and MMSE at weeks 4, 12, and 24) also revealed statistically significant benefit in both groups compared to baseline with no significant differences between groups. Statistically significant improvement was noticed on CGI-S and CGI-C scales in both groups. Akatinol Memantine was safe and well tolerated in both groups. CONCLUSION:The study showed no lesser efficacy and safety of Akatinol Memantine, 20 mg (once daily) compared to Akatinol Memantine, 10 mg (twice daily) in patients with moderate and moderately severe vascular dementia.

OBJECTIVE:To study the severity and localization of dilated perivascular spaces (DPVS), the levels of protein markers of amyloidosis and neurodegeneration in the cerebrospinal fluid (CSF) at different daily blood pressure (BP) profiles in patients with Alzheimer's disease (AD) and other types of cognitive impairment.MATERIAL AND METHODS:A total of 119 people, aged 53 to 92 years, including 55 patients with AD, 27 patients with vascular cognitive disorders (VCD), 19 patients with frontotemporal degeneration (FTD). All patients underwent BP monitoring for 24 hours using a standard oscillometric measurement method, lumbar puncture to assess Aβ-42 and Aβ-40 amyloid protein, total and phosphorylated tau protein in the CSF, magnetic resonance imaging tomography of the brain with subsequent assessment of the severity of expansion and localization of DPVS according to the G.M. Potter scale.RESULTS:In 58.3% of patients with AD, there is no adequate reduction in BP at night in comparison with patients with VCD (p<0.05). A significant degree of expansion of the DPVS turned out to be most typical for patients with AD: grade 3 was detected in 45.7% of patients, and the maximum, grade 4, was detected in 13.4%. At the same time, DPVSs were significantly more often detected in the group of subjects with insufficient reduction in diastolic BP (DBP) at night. A strong inverse correlation was established between the level of Aβ-42 in the CSF and the variability of DBP at night (r= -0.92; p<0.05). The decrease in the level of Aβ-42 in AD, especially at the prodromal stage, is directly related to the low variability of DBP at night, which is more characteristic of an insufficient decrease or increase in BP during night sleep.CONCLUSION:Patients with AD were characterized by an insufficient decrease in BP at night, which is associated with the severity and degree of maximum expansion of the DPVS. A decrease in the level of Aβ-42 amyloid protein in the CSF strongly correlates with the variability of DBP at night.

Perioperative ischemic stroke is a potentially fatal complication that greatly increases the risk of poor outcome in surgical patients. Despite the relatively low prevalence among patients undergoing non-cardiosurgical and non-neurosurgical interventions (about 0.1–1.0 %), the total number of annually developing perioperative ischemic strokes in patients of this profile is high due to the large number of operations performed in the world. Since the publication in 2014 of the last fundamental work on the prevention of perioperative stroke, approaches to primary and secondary prevention, diagnosis, conservative and reperfusion treatment of ischemic stroke have been seriously modified. The numerous changes that have taken place have created the prerequisites for revising existing approaches to providing care for perioperative ischemic stroke. In 2021, updated documents of foreign researchers/ associations on the problem of perioperative ischemic stroke in non-cardiac and nonneurosurgical patients were published. This review, which consists of two parts, presents current data that summarizes the most relevant information on this topic. The first part of the review outlines the general provisions on perioperative ischemic stroke (definition, risk factors, pathogenesis, predictive models), strategies for pre- and intraoperative prevention.

The prognosis for recovery from a vegetative state (VS) remains underdeveloped. Objective. To determine the feasibility of prognosis for recovery from a vegetative state based on clinical comparison of 18- fluorodeoxyglucose-PET (18FDGPET) and MRI (SCT) data. Materials and methods. We compared and analyzed retrospectively cerebral PET and MRI (SCT) scans and relevant prognostic criteria (including revised coma recovery scale — CRS-R scores) prospectively during 6–84 months of follow-up in a cohort of 39 VS patients. All VS cases were of different etiologies, lasting for more than 2 months after brain damage (including 18 patients in chronic VS). Pairwise comparison of groups was used (significance level P 0.05) and multiple comparison for three groups with a Bonferroni correction at P 0.017 was employed. Results. Three patterns were identified when comparing 18FDGPET and MRI (SCT) neuro-images: pattern I — the area of functional alterations was larger than the area of structural damage, pattern II — complete matching of areas of structural and functional alterations, III — mixed pattern. Pattern I (69% of cases) was more common than patterns II (18%), and III (13%), P 0.001. There were no differences in VS etiology, VC duration, CRS-R scores, patients’ gender and age between the groups of patients each falling into one of patterns. The outcome in a group with pattern I patients (all of them recovered from VS) was better than in other two groups exhibiting patterns II or III, each, P 0.001. In a group of patients with pattern III the recovery was better than in pattern II (all patients remained in VS), P =0.018. The increases in the total CRS-R score values were as follows: 12,1±4,46; Me=12 (4–19), N =27 (patients with a pattern I); 0±1,54 (–2–1, Me =0, N =7 (patients with a pattern II); and 5,20±4,09/ Me =4 (1 — 10), N =5 (patients with a pattern III). Significant increases in neurological improvement were revealed in pattern I patients with non-chronic VS versus chronic VS, P =0.003. Conclusion. Clinical comparison of PET/MRI (SCT) data showed certain potential to predict patient’s recovery from VS in 87% of cases. A retrospectively confirmed favorable prognosis in patients with pattern I was established in 69% cases, unfavorable (pattern II patients) was defined in 18% cases, regardless of other prognostic criteria, including chronic VS. Therefore, the data confirms the feasibility and clinical relevance of neurophysiological justification as a candidate approach for evaluating the prospect of recovering patients from VS.

Introduction . In the context of the search for new migraine therapy options, strict control of their eff ectiveness by means of objective examination methods is required. Objective . Objective assessment of the eff ectiveness of TMS in patients with migraine on the basis of functional magnetic resonance imaging (fMRI) data. Material and methods . Resting-state fMRI before and after a fi ve-day course of TMS of the junction of the inferior frontal and temporal lobes bilaterally was performed in 19 patients with migraine. Changes in functional connectivity (FC) of the main neuronal networks of the brain, as well as clinical parameters of pain and quality of life of the patients were assessed before and after the course of TMS. Results . A decrease in pain intensity and anxiety scores, as well as a decrease in the number of acute pain medications taken, was observed against the background of the therapy. Changes in FC aff ected three main networks: the default mode network, the salience and visual networks. At the same time, decreased effi cacy of therapy was noted in patients with higher severity of depressive symptoms and presence of neuroimaging criteria of depression. Conclusion . The study suggests the effi cacy of TMS in patients with migraine based on neuroimaging criteria. It is worth paying special attention to the presence of depressive symptoms in migraine patients.

Diagnosis and treatment of early forms of cognitive impairment: possibilities of influencing neuronal energy metabolism. Resolution of the Council of Experts.

Muscular-tonic disorders (MTD) in prolonged disorders of consciousness (PDoC), including a vegetative state (VS) and a minimal consciousness state (MCS), are poorly understood.Aim. To systematize MTD in PDoC, to highlight the features of their dynamics depending on the change in consciousness.Material and methods. 87 patients in PDoC (VS — 52, MCS — 35) resulting from brain damage of diff erent etiology, lasting from 2 months up to 10 years. MTD, provoking hyperkinesis factors and consciousness were analyzed retrospectively in the dynamics and complex.Results. MTD had 98% of patients in PDoC. The ratio of occurrence of spasticity: hyperkinesis: postural spasms corresponded to 11:11:10, and hyperkinesis — dystonia: myoclonus/myokymia: athetosis: stereotypes: ballism: choreiform hyperkinesis: tremor — 17:10:6:3:2:1:1. Their clinical variants and features are noted. The total dynamics of MTD on improved consciousness was as follows. In general, regardless of the initial VS or MCS, their “change” (especially decrease) prevailed over “no changes” (p < 0.001). Comparatively more often the decrease occurred in MCS “plus” (p < 0.05); appearance/increase/modifi cation — in VS (p < 0.05); “no changes” — in MCS “minus” (p < 0.01). When considered separately, spasticity, dystonia, spasms, hemiballismus and stereotypy in MCS “plus” correlated (p < 0.01) with the change of consciousness. The key provoking hyperkinesis factors in VS were pain and other sensory infl uences (p < 0.01), but their role from MCS “minus” to MCS “plus” decreased, while the role both conscious emotions and movements increased (p < 0.01).Conclusion. Along with academic interest, the data are promising in developing the prognosis, pathogenesis and treatment of PDoC.

The peculiarities of the influence of cytokines and metabolites of the systemic inflammatory reaction and stress-implementing and nutritional factors contributing to the transformation of the phenotype of the resident intestinal microflora with an increase in its virulence are described. From the perspective of expression of genes and conformations of proteins and phospholipids, the influence of temperature as a signaling factor in increasing the virulence of the intestinal microbiome is considered. Evolutionarily formed mechanisms of expression of the maximum pathogenic phenotype of microorganisms and, thus, achieving an increase in their biomass and maximum dissemination through the microorganism compartments increase the probability of the transmission of commensals to another biotope, i.e., increases the probability of their survival after the death of the host organism. To prevent bacterial translocation after the relief of critical conditions, early enteral administration of β-glucans in food mixtures, iron excretion, and relief of inorganic phosphate deficiency, including by induction of alkaline phosphatase synthesis, are substantiated.

The benign monomelic amyotrophy of the lower limb is a slowly progressive disease that is clinically manifested by muscle atrophy in only one lower limb. This disease is quite rare, while it is most common in Asian countries (about 80 cases have been described). According to the literature a total of 16 cases of benign monomelic amyotrophy of the lower limb were described in Europe by 2000. Etiology and pathogenesis have not been reliably studied now. The article presents a clinical case of the development of this disease in a 42-year-old patient. The patient was admitted with complaints of weakness in the right leg and its decrease in volume. During the period of hospitalization, diff erential diagnosis was carried out with amyotrophic lateral sclerosis, progressive muscle atrophy, Hirayama disease, vascular and paraneoplastic processes. According to the results of a comprehensive laboratory and instrumental examination, the diagnosis was fi rst established: benign monomelic amyotrophy of the lower limb. The father of a patient who had atrophy of the muscles of the left lower limb would also be examined. According to the data of hereditary anamnesis, an assumption was made about the presence of the phenomenon of anticipation in the inheritance of benign monomelic amyotrophy of the lower limb. This article describes for the fi rst time a case of benign monomelic amyotrophy of the lower limb in the domestic literature, as well as a familial case of this disease all over the world.

Study Objective: To study the incidence and the structure of the postoperative cerebral dysfunction after open and endovascular aortic valve replacement surgery, and to identify the risk factors and the methods of prevention of postoperative cerebral dysfunction after the open aortic valve replacement surgery. Study Design: Prospective cohort study. Materials and Methods. The study involved 114 patients (92 men and 22 women) aged 67 [58; 76] years, who undergone elective aortic valve replacement surgery. All patients were divided into three groups: “open surgery” (n = 82), “cerebroprotection” (n = 16) and “X-ray surgery” (n = 16). In the “open surgery” and “cerebroprotection” groups, patients undergo open aortic valve replacement surgery with cardiopulmonary bypass, in the “X-ray surgery” group transcatheter aortic valve implantation is performed. In the “cerebroprotection” group patients additionally received the 1.5% solution of meglumine sodium succinate in the early postoperative period. Study Results. The postoperative cerebral dysfunction was diagnosed in 41.2% of patients, the incidence of the postoperative cerebral dysfunction did not differ in the study groups. In the group “cerebroprotection” there was a shorter duration of symptomatic delirium of the early postoperative period (p = 0.0441) compared with the group “open surgery”. We identified 18 risk factors for postoperative cerebral dysfunction and its clinical types and two cerebroprotective factors — a body mass index more than 25 kg/m2 and the use of the meglumine sodium succinate in the early postoperative period. Conclusion. Aortic valve replacement surgery is characterized by the high incidence of the postoperative cerebral dysfunction, further improvement of the methods of the perioperative cerebroprotection is required. Keywords: postoperative cerebral dysfunction, perioperative stroke, symptomatic delirium of the early postoperative period, postoperative cognitive dysfunction, perioperative cerebroprotection, aortic valve replacement.

The care of a patient with Alzheimer's disease (AD) is considered from the perspective of an ecosystem, that is, a systemic approach describing effective partnership, collaboration and research aimed at creating value, involving all participants in the AD patient journey. The effectiveness of this ecosystem is only possible with the involvement of all stakeholders in its development, including patients, healthcare professionals at all levels, government agencies, private companies, and patient organizations. The unmet health care and information needs of patients with AD are a consequence of barriers in the AD ecosystem. Key barriers for the patient include low awareness and stigmatization of the disease in society, lack of quality epidemiological data, difficulties in timely diagnosis, lack of prevention programs, unpreparedness of most physicians to conduct AD patient rehabilitation, and other factors. Based on the analysis of the ecosystem of AD and the patient pathway, 10 main directions (strategies) necessary for the formation of the ecosystem were identified: conducting research in the diagnosis and epidemiology of AD, creating and implementing a cognitive health program, forming a legal framework, raising public awareness, optimizing patient routing for timely diagnosis, organizing a network of memory clinics/laboratories, creating a register of patients with dementia, developing digital solutions and supporting social projects.

In-hospital ischemic stroke (IHIS) is one of the most critical competing diseases that can develop in patients during inpatient treatment. Causes associated with diagnostic and therapeutic measures may play an additional role in the pathogenesis of IHIS, in addition to traditional risk factors. Objective : to study the pathogenesis features and assess risk factors for IHIS. Patients and methods . The comorbidity, main and additional risk factors of IHIS in patients of therapeutic (n=112; 44.3%), surgical (n=125; 49.4%) and neurological (n=16; 6.3%) profiles were studied. Results and discussion . The proportion of perioperative stroke in the study was 37.2%. The frequency of atherothrombotic, cardioembolic, and lacunar subtypes of IHIS did not differ in groups of patients of different profiles. In the group of surgical patients, the proportion of strokes of another established etiology was 24.8% and was higher than in therapeutic (9.8%; p<0.05) and neurological (6.25%; p<0.005) patients. The proportion of strokes of unknown etiology in the group of surgical patients, on the contrary, was lower (15.2%) than in patients with therapeutic (35.7%; p<0.05) and neurological (50.0%; p<0.05) profile. An additional risk factor for IHIS for non-surgical patients was insufficient antithrombotic prophylaxis, for surgical patients – surgery. Conclusion . Compared with out-of-hospital ischemic stroke, the causes of in-hospital ischemic stroke are more diverse and cannot always be explained solely by the higher comorbidity of hospitalized patients. The TOAST classification of ischemic stroke subtypes does not fully reflect the pathogenesis of IHIS, as it does not take into account the possibility of external influences, especially in cases where it is not possible to establish the exact cause of stroke, and the most likely trigger is medical intervention.

Background. Epileptic seizures represent one of the leading clinical manifestations of glial brain tumors that develop on average in 51% of cases. In gliomas, epileptogenesis is quite complex and multifactorial.Objective: to study a role of the expressed glutamine synthetase enzyme, as well as cystine/glutamate transporter (xCT system, SLC7A11) in the pathogenesis of epilepsy developing in patients with cerebral gliomas.Material and methods. The study included 32 patients with supratentorial gliomas. The average age of the disease onset (diagnosis) was 50.69±18.01 years. All patients underwent inpatient examination and treatment at the Neurosurgery and Nervous Diseases Clinics of Kirov Military Medical Academy from 2018 to 2020. In all cases, a biopsy of tumor tissue was collected. Histological and immunohistochemical studies were performed (expression of glutamine synthetase and cystine/ glutamate transporter (SLC7A11, xCT)).Results. Significant (ANOVA p=0.027, Mann–Whitney U-test p=0.033) differences in the expression of cystine/glutamate transporter (xCT system, SLC7A11) were revealed, by showing the following median values (lower quartile; upper quartile): 50% (45; 75) in the group of patients with seizures, 40% (40; 50) in the seizure-free group. The expression level of glutamine synthetase did not significantly differ in the groups with and without seizures.Conclusion. The data obtained confirmed that one of the pathogenetic mechanisms for epilepsy development in patients with gliomas was related to highly expressed cystine/glutamate transporter (xCT system, SLC7A11) and, as a consequence, an increase in the extracellular glutamate level.