Arterial spin labeling (ASL) perfusion MRI represents a modern non-invasive approach to assessing tissue perfusion that is gaining increasing importance in clinical and research practice. Unlike traditional contrast-enhanced methods, ASL enables quantitative blood flow evaluation without the need for contrast agents, which is particularly valuable in certain clinical scenarios and for longitudinal patient monitoring. This review synthesizes current data on ASL perfusion applications, including key clinical uses and future development prospects. The topic’s relevance stems from growing interest in functional imaging techniques and the need for ASL protocol standardization to facilitate widespread clinical adoption.

Purpose: To evaluate the diagnostic capabilities of ASL perfusion MRI by analyzing current applications and future development trends based on contemporary scientific evidence.

Material and methods. A retrospective review of randomized clinical trials and cross-sectional studies was performed from PubMed, EMBASE, LILACS, Scopus, and eLibrary databases (2015–2025) using search terms: «arterial spin labeling,» «pulsed ASL,» «continuous ASL,» «pseudo-continuous ASL,» «diffusion-prepared ASL,» «artificial intelligence ASL,» and their Russian equivalents.

Results. From 132 screened publications, 81 were selected for analysis. The review examined ASL technique variations, clinical applications, and emerging trends in the field. Conclusions. ASL perfusion is a promising non-invasive method for tissue blood flow assessment with demonstrated diagnostic utility across multiple pathologies. Future development potential lies in methodological optimization, artificial intelligence integration for data processing, and protocol standardization for routine clinical implementation.

Medications used in Alzheimer’s disease are currently aimed primarily at eliminating the symptoms of the disease, while more modern drugs based on monoclonal antibodies are still of limited use. In this work, an analysis of drugs for the treatment of Alzheimer’s disease was carried out, including a review of clinical trials and drugs used in clinical practice.

Results and discussion. The main approaches to therapy are analyzed: drugs for basic therapy (cholinesterase inhibitors, memantine) and new drugs based on monoclonal antibodies (lecanemab, donanemab) aimed at beta-amyloid, which demonstrate the ability to slow cognitive decline in the early stages of the disease, but are associated with the risk of amyloid-related imaging abnormalities (ARIA). Promising areas are also considered: tau protein-targeted therapy, the use of glucagon-like peptide 1 receptor agonists (semaglutide), neuroinflammation modulation (interleukin-2), and gene therapy. It was revealed that the majority of clinical trials (208 in phase I‒III) are focused on anti-amyloid drugs and reducing the accumulation of tau proteins in the brain.

Conclusions. The development of drugs is shifting from symptomatic to pathogenetic therapy. Despite the appearance of anti-amyloid antibodies, their use is limited by risks and high cost. Promising areas of therapy are the development of bispecific antibodies, combination therapy connecting several mechanisms, as well as gene therapy.

Neurofeedback (NF) is a noninvasive neuromodulation technology achieved by teaching the subject the skill of selfregulation of certain parameters of their own brain activity in a feedback loop. It is believed that such mental training leads to changes in the functional architecture of global cerebral networks, involving neuroplasticity mechanisms, and therefore may have potential in stroke rehabilitation. EEG-NF has a long history and traditionally uses frequency bands of EEG rhythms associated with known behavioral functions as an adjustable parameter. The development of MRI technology has made it possible to obtain topographically accurate functional images of the brain (fMRI) in real time with the prospect of creating fMRI-NF-platforms. Online fusion of signals from two modalities (EEG and fMRI) in a feedback loop for self-regulation training (fMRI-EEG-NF) is attractive due to its therapeutic and research potential, promising a more detailed understanding of spatio-temporal dynamics in the brain after stroke, which is impossible to obtain using each modality separately. However, such a multimodal functional neuroimaging requires non-trivial hardware and computational solutions. The objective of the review was to trace the vector of development of the NF technology in relation to stroke rehabilitation in the historical and technological aspect. For this purpose, the theoretical and practical prerequisites for fusion of fMRI and EEG signals in a feedback loop are summarized and data on the effectiveness of NF methods as a scientifically based method of recovery after stroke are presented.

Ischemic stroke remains one of the leading causes of mortality and disability worldwide, necessitating improvements in early diagnostic methods. Despite the widespread use of computed tomography (CT), detecting early signs of ischemia remains challenging due to the modality’s limited sensitivity during the initial hours. Artificial intelligence (AI) technologies show potential for enhancing diagnostic accuracy, including the identification of cerebral ischemia signs, though their clinical applicability requires rigorous evaluation.

Aim of the study was to evaluate the diagnostic performance of AI-based services for automated analysis of brain CT scans in detecting acute ischemic lesions within the Moscow Experiment framework.

Material and methods. We conducted a retrospective study of 100 non-contrast brain CT scans (50 with ischemic stroke, 50 normal controls) selected from the Unified Radiological Information Service of Unified Medical Information and Analytical System of the City of Moscow. Diagnosis verification was performed by two independent radiologists, with expert consultation in disputed cases. We assessed the following metrics: sensitivity, specificity, accuracy, and area under the ROC curve (AUC) with 95 % confidence intervals. Scans were processed by three comprehensive AI services specifically designed to detect pathological changes on non-contrast brain CT scans in patients with suspected acute ischemic stroke.

Results. Two of the three AI services demonstrated high diagnostic accuracy: AUC > 87 %, sensitivity ≥ 83 %, specificity ≥ 83 %. The third service showed reduced sensitivity (68%), indicating a risk of missed diagnoses.

Conclusions. AI services can serve as effective decision-support tools in ischemic stroke diagnosis, particularly in time-constrained scenarios or when expert resources are limited. However, the observed variability in performance underscores the necessity for strict validation before clinical implementation.

Cardioembolic stroke (CES) is a common and severe variant of ischemic stroke. Cardioembolic stroke (CES) is a common and severe form of ischemic stroke, the main risk factor for which is atrial fibrillation. Among deceased patients with acute cerebrovascular accident, 40 % die in the first 48 hours of inpatient treatment. This demonstrates the importance of the in-hospital mortality (IHO) indicator and the search for its predictors with the construction of prognostic models using machine learning methods. The aim of the study was to develop prognostic models of IHO in patients with CES and AF based on modern ML methods. Material and methods. The study included 259 patients with CES and AF who were admitted to the regional vascular center No. 1 of Novosibirsk from November 2022 to December 2023. Logistic regression, random forest, stochastic gradient boosting and categorical boosting were used to develop prognostic models. Results and discussion. During the study, statistically significant differences were found between those who died and those who were discharged in terms of age, the presence of nosocomial and communityacquired pneumonia, chronic kidney disease, the number of comorbidities, as well as the values of scales and indices upon admission (the sum of points on the NIHSS (The National Institutes of Health Stroke Scale), Rankin scale, RRS (rehabilitation routing scale), and the Rivermead index. The prognostic significance of these parameters was assessed using univariate logistic regression. Prognostic models of IHO were developed based on machine learning methods. The models based on NIHHS and RRS had the greatest predictive potential, which was shown in a comparative analysis of the ROC curves of the developed models. The contribution of the predictors of these models to the implementation of the end point was estimated using the Shapley method. Conclusions. In our study, the highest prognostic value for CES and AF was demonstrated by the NIHSS, Rankin scale, and RRS scores, the Rivermead index at admission, the presence of nosocomial and community-acquired pneumonia, chronic kidney disease, and age. The resulting models, when widely implemented, will enable personalized management of the risk of IHO in patients with CES and AF.

Aim of the study was to evaluate the dynamics of changes in functional brain networks (default mode network, DMN, and sensorimotor network, SMN) during the early recovery period following ischemic stroke, taking into account the volume of ischemic lesions according to MRI data. Material and methods. A dynamic MRI study of the brain was performed on a 3.0 T scanner in 137 patients at 1–3 days, 7–10 days, and 3–4 months after the onset of acute cerebrovascular accident, using a routine protocol (DWI-EPI, FLAIR-SPIR, T2-WI, T1W-TFE) supplemented with resting-state functional MRI. Additional assessment included the Montreal Cognitive Assessment (MoCA) and the modified Rankin scale. The study cohort comprised 36 patients diagnosed with acute ischemic supratentorial stroke who underwent at least two MRI examinations. Results and discussion. A trend (p > 0.05) towards increased functional connectivity between DMN and SMN regions was observed from the first to the third examination. The MoCA results (p < 0.05 for 2nd and 3rd study compared to 1st) showed improvement in cognitive functions over time, consistent with the clinical course. The most significant finding of the correlation analysis was a direct correlation between DMN and SMN connectivity at the first observation (R = 0.57; p = 0.006). Lesion volume was found to influence functional connectivity, with a significant effect of larger lesion size on DMN recovery dynamics (R = 0.83; p = 0.04). Conclusions. A parallel increase in intra-network connectivity of the DMN and SMN was demonstrated, indicating systemic functional reorganization of the brain following acute stroke. During the early recovery period, resting-state functional MRI revealed progressive restoration of DMN and SMN connectivity, accompanied by cognitive improvement as assessed by MoCA. Further research is required to clarify the mechanisms of DMN and SMN recovery, as well as the role of lesion volume and localization in functional network reorganization.

Radiologically isolated syndrome (RIS) is currently considered an early preclinical stage of multiple sclerosis (MS). RIS is characterized by typical brain or spinal cord lesions indicative of autoimmune inflammatory demyelination.

The aim of the study was to assess the frequency of RIS according to the updated 2023 criteria among a cohort of the Novosibirsk MS Center and to determine the time to the first clinical episode of demyelination. A secondary objective of the study was to conduct a comparative analysis of MRI quality characteristics in subgroups of patients with and without two-year MRI activity, as well as in subgroups of patients with and without conversion to MS throughout the entire follow-up period.

Material and methods. The study design was retrospective, with analysis of baseline and follow-up data. MRI activity in patients with RIS was measured annually. Forty-five patients who met the 2023 RIS criteria were included in the analysis.

Results and discussion. MRI activity, defined as the appearance of two or more new lesions or one or more contrast-enhancing lesions, was detected in 30 of 45 (67 %) patients during two-year follow-up. Patients with MRI activity were more likely to progress to definitive MS than patients without MRI activity (53.0 and 6.7 %, respectively, p < 0.001). Multiple logistic regression confirmed an increased risk of developing a first clinical episode in the group of patients with subsequent MRI activity (odds ratio 16.01, 95% confidence interval 1.52–168.17, p = 0.02). Earlier diagnosis of multiple sclerosis at the preclinical stage became possible after the introduction of the updated McDonald criteria (2024). Among asymptomatic RIS patients, compliance with the new MS criteria was confirmed in 71 % (20/28).

Conclusions. The study confirmed the presence of spinal lesions on the initial MRI as a key prognostic risk factor for clinical conversion of RIS to MS. The use of user-friendly biomarkers in real-world clinical practice may increase the potential for personalized clinical intervention and requires further study.

Age-related diseases of the nervous system, such as Alzheimer’s disease (AD) and cerebral small vessel disease (cSVD), are characterized by cerebral atrophy. The use of modern neuroimaging techniques determines the possibility of moving from qualitative approaches to atrophy assessment to quantitative ones. Data on the characteristics of cerebral atrophy in vascular pathology of the brain compared to neurodegenerative diseases are limited.

The aim of the research is to clarify the differences in regional atrophy in AD and cSVD and the sensitivity of various approaches to its assessment.

Material and methods. The study included 45 patients with cSVD (48.9 % women, 51.1 % men, age 64.6 ± 5.7 years, mean ± standard deviation), 26 patients with AD (61.5 % women, 38.5 % men, mean age 66.1 ± 7.9 years), 19 healthy volunteers (68.4 % women, 31.6 % men, age 63.2 ± 4.5 years). The groups were comparable by age and gender. MRI scanning was performed on a Siemens Magnetom Prisma tomograph (Siemens AG, FRG, 3 T). Qualitative assessment of parietal lobe atrophy was performed using the Koedam scale, frontal and occipital lobes – using the global cortical atrophy scale (GCA), hippocampi – using the medial temporal atrophy scale (MTA). For all study participants, the following parameters were calculated: ventriculocranial coefficients for assessing internal cerebrospinal fluid spaces, volumetric indices (gray and white matter volume, white matter hyperintensity, cerebrospinal fluid and total intracranial volume), as well as the thickness of individual areas of the cerebral cortex using the surface morphometry method.

Results. Statistically significant differences in the atrophy pattern were revealed: a decrease in the total intracranial volume was noted in AD with a predominant regional decrease in the volume and thickness of the cortex in the temporal and parietal lobes, whereas in cSVD the atrophy affected the anterior parts of the frontal lobes to a greater extent. The minimum thickness of the cortex in cSVD was obtained in the cingulate gyri.

Conclusions. The use of volumetric and morphometric methods for the evaluation of MRI images allowed us to identify differences in regional atrophy in AD and cSVD with the detection of special patterns that suggest differences in the mechanisms of development and progression of the studied diseases. The use of various approaches to atrophy assessment may be important in identifying mixed forms of the pathology.

Stroke leads not only to local damage but also to large-scale reorganization of brain networks, including motor regions and interhemispheric interactions. Modern diffusion MRI methods allow for the study of microstructural dynamics in white and gray matter; however, the classical tensor model has limitations in describing complex fiber architectures. The introduction of kurtosis-based approaches increases sensitivity to tissue heterogeneity, making it a promising tool for analyzing neuroplasticity in the context of rehabilitation.

The objective of the research is to provide a quantitative description of the dynamics of diffusion-based metrics (both tensor and kurtosis) in the motor network under functional MRIand EEG-guided neurofeedback and to identify prognostic markers of therapeutic efficacy of interactive neurorehabilitation.

Material and methods. Fourteen patients (10 men, 4 women; mean age 58 years) who had experienced ischemic stroke within the previous 6 months were enrolled. Patients were randomized into the main group (n = 7), which underwent an fMRI-EEG neurofeedback course, and the control group (n = 7), which received only standard rehabilitation. Each participant underwent three consecutive stages of clinical and neuroimaging assessment (before therapy, immediately after the course, and at 6-month follow-up). Diffusion tensor imaging (DTI) was used for tract reconstruction, and diffusion kurtosis imaging (DKI) – for analyzing kurtosis parameters in gray and white matter, including the premotor and supplementary motor cortices as well as the corpus callosum.

Results. In gray matter, late-stage follow-up revealed a decrease in kurtosis fractional anisotropy (kFA), more pronounced in the control group, interpreted as a decline in microstructural organization. In white matter, signs of axonal loss and demyelination were observed in the lesion area, accompanied by fiber remodeling detected by tractography. The main group demonstrated a trend toward the formation of new interhemispheric connections via the II–III segments of the corpus callosum, while the control group showed predominantly densification of pre-existing pathways. Clinical outcomes improved significantly more in the main group (modified Rankin scale, Fugl–Meyer scale, handgrip strength, Box-and-Blocks test, CES-D questionnaire (Center for Epidemiologic Studies Depression Scale)). Discussion. The findings confirm the complementarity of DTI and DKI: the former is more sensitive to myelination and axonal integrity, while kurtosis enables detection of cortical microstructural changes. Correlations between diffusion metrics and functional outcomes highlight their prognostic value in assessing rehabilitation efficacy.

Conclusions. Interactive neurorehabilitation promotes structural reorganization of the motor network and leads to significant clinical improvement. Diffusion metrics, including fractionation anisotropy, radial diffusion, and kFA, may serve as objective biomarkers of neuroplasticity and therapeutic effectiveness in the early recovery period after stroke.

Parkinson’s disease (PD) involves degeneration of nigrostriatal dopaminergic neurons with a consequent imbalance across multiple neurotransmitter systems regulating basal ganglia function. Amantadine (AMD; 1-aminoadamantane) is a low-affinity, uncompetitive NMDA receptor antagonist and a modulator of CNS neurotransmission that alleviates motor symptoms of PD but is limited by modest efficacy. Azaadamantanes bearing a monoterpene moiety are proposed as aminoadamantane analogs with potential to stimulate dopaminergic transmission and antagonize glutamatergic NMDA receptors.

Aim of the study was to compare the effects of monoterpene-containing azaadamantanes (K-372, K-818) and AMD on key neurotransmitter systems implicated in PD pathogenesis using validated in vivo models.

Material and methods. Male CD-1 and C57BL/6 mice received a single intraperitoneal dose of each agent at 20 mg/kg. Outcomes were measured in the following models: parkinsonism, induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), haloperidol-induced catalepsy, arecoline-induced tremor, yohimbine toxicity, and corazole-induced seizures models.

Results and discussion. In the MPTP model, K-372 and K-818 significantly improved locomotor and exploratory activity, indicating dopaminergic stimulation, whereas AMD significantly improved only one locomotor endpoint (p<0,05). In haloperidol-induced catalepsy, only K-818 showed significant anticataleptic activity comparable to AMD, whereas K-372 had no effect. In the arecoline tremor assay, K-372 and K-818 prolonged latency and reduced tremor duration more effectively than AMD, suggesting a moderate central antimuscarinic action, while AMD produced no significant effect. In yohimbine toxicity model, K-372 and K-818 decreased animal survival, corresponds to potentiation of adrenergic transmission, whereas AMD showed a modest trend toward lower toxicity. In the corazole model, none of the agents altered seizure latency, indicating no evidence of GABAergic stimulation, which aligns with a mechanism resembling amantadine.

Conclusions. K-372 and K-818 demonstrate robust antiparkinsonian activity in the MPTP model and efficacy against muscarinic arecoline-induced tremor in mice, while exhibiting adrenergic potentiation and no signs of GABAergic stimulation.

Objective. To evaluate structural retinal changes in patients with relapsing-remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS) over time and to analyze their association with the progression of neurological impairment.

Material and methods. Clinical data (EDSS, T25FW, 9-HPT, SDMT) and optical coherence tomography (OCT) results (average thickness of the ganglion cell and inner plexiform layer [avgGCL+IPL]; average thickness of the peripapillary retinal nerve fiber layer [avgRNFL]) were analyzed in patients with RRMS and SPMS (42 women, 19 men; age 46.20 ± 9.49 years) over a follow-up period of 12.87 ± 1.25 months. Comparisons were performed between groups stratified by disability level (Group 1: EDSS 0–2.0, Group 2: EDSS 2.5–3.5, Group 3: EDSS≥4.0), as well as by the presence of at least one sign of progression (increase in EDSS by 0.5–1.0, ≥20 % worsening in T25FW/9HPT, or ≥4-point/10 % decrease in SDMT).

Results and discussion. EDSS did not change significantly during follow-up (p = 0.451); however, 45.2 % of patients demonstrated signs of progression according to T25FW/9HPT/sDMT. T25FW performance worsened more markedly in Groups 2 and 3 (p < 0.001), while no significant differences were observed between groups in other measures. Statistically significant differences in avgGCL+IPL and avgRNFL were found between Groups 1 and 3 (p = 0.007 and p = 0.016, respectively). Annual avgGCL+IPL change was −0.58 [−1.00; −0.17] μm in Group 1 vs. −3.00 [−3.33; −1.25] μm in Group 3; annual avgRNFL change was −0.62 [−1.75; 0.75] μm in Group 1 vs. −2.38 [−3.25; −1.88] μm in Group 3. Moreover, annual reductions in avgGCL+IPL and avgRNFL were greater in patients with progression (−1.54 [−3.00; −0.46] and −2.31 [−4.69; −1.25] μm, respectively) compared with stable patients (−0.83 [−1.50; −0.25] and −0.75 [−1.88; 0.50] μm, respectively), with statistically significant differences (p = 0.018 and p = 0.003, respectively). Progression was predicted by avgGCL+IPL loss >1.17 μm/year (sensitivity 64.3%; specificity 66.7 %) and avgRNFL loss >1.125 μm/year (78.6 and 63.6 %, respectively).

Conclusions. Accumulation of neurological deficits occurs even in the absence of EDSS changes, while the neurodegenerative process is more active in patients with greater disability and longer disease duration. Annual thinning of avgGCL+IPL and avgRNFL on OCT may serve as a predictor of MS progression.

Aim of the study was to propose a practical method for T2*-relaxometry of fetal brain white matter using prenatal MRI, adapted to real-world clinical conditions and the specific limitations of prenatal imaging.

Material and Methods. A multi-echo echo-planar imaging (EPI) sequence was used to acquire a series of images with different echo times within a single breath-hold. T2* values were calculated using ROI (region of interest) analysis of manually annotated white matter regions, with exponential fitting of the signal decay. The method was adapted to the constraints of prenatal MRI, including fetal motion, the influence of amniotic fluid, dielectric artifacts at 3T, and the need to balance resolution with scan time.

Results. The method yielded reproducible T2* values in fetuses during the second and third trimesters: 182 ± 11 ms at 1.5T and 153 ± 13 ms at 3T, both higher than those in adults (66.2 ± 2.5 and 51.8 ± 2.9 ms, respectively). Agreement between two T2* calculation methods was high (intraclass correlation coefficient 0.955, p < 0.0001). The method shows promise for assessing fetal hypoxia.

Conclusions. With appropriate scanning and post-processing settings, T2*-relaxometry can be successfully applied to prenatal MRI. The proposed solutions overcome key limitations and pave the way to further clinical and research use of the method.

The use of artificial intelligence (AI) technologies in clinical trials (CT) of medicines has led to a significant reduction in time and financial costs for the development of new medicines. However, their widespread adoption faces a number of unresolved issues related to data quality, regulation, ethics, and security.

The purpose of this study was to assess the current state of AI application in CT and identify key issues hindering its widespread adoption.

Results and discussion. The key applications of AI in CT are analyzed: the use of large language models (TrialGPT, Elsa) for data analysis, the creation of digital patient counterparts and synthetic controls for CT modeling, as well as predictive analytics to optimize research design and risk assessment. It has been shown that these methods can improve the efficiency of patient selection, predict outcomes with a high area under ROC score (up to 92.7 %), and accelerate drug development. However, serious limitations have been identified: the dependence of the quality of models on the representativeness of data, the risks associated with imperfect algorithms, as well as the lack of specialized regulatory regulation and standards, including in the Russian Federation. The problems of data confidentiality, obtaining informed consent, and determining responsibility for harm caused by the use of AI are highlighted.

Conclusions. The widespread use of AI to increase the efficiency and personalization of CT, its scaling requires solving complex regulatory, legal and ethical challenges.

The harmonization of legislation in the Eurasian Economic Union (EAEU) creates a single market for medicines, which requires the unification of intellectual property rights protection.

The purpose of this work was to analyze trends in patenting and intellectual property rights protection in the EAEU and, in particular, for the Russian Federation, as the largest market for medicines.

Material and methods. An analysis of 311 patents from the Pharmaceutical Register of the Eurasian Patent Office (EAPO) for 1996–2025 was performed. Principal component analysis and k-means clustering methods were used for the analysis.

Results and discussion. The dominance of foreign companies (USA and EU, 94.2% in total) in the structure of EAPO patents in the EAEU has been established. The majority of patents cover drugs for the treatment of cancer, HIV infection and type 2 diabetes. The principal component analysis revealed statistically significant differences in the terms of patent protection before and after 2025. Using cluster analysis, three groups of drugs were identified by patent expiration dates and indications for use; it was revealed that the expiration of patent protection for medicines for the treatment of socially significant diseases is expected in the period 2029–2032.

Conclusions. The study confirms the dominance of foreign EAPO patents in the EAEU market, but identifies opportunities for local manufacturers due to the upcoming expiration of numerous patents. The introduction of a “patent linkage” mechanism is necessary for further harmonization at the EAEU level, especially for the protection of biosimilar and biotechnological drugs, and for the more effective development of the common pharmaceutical market.

Cerebral aneurysms are a significant disease that can lead to both disability of the patient and death. Despite the fact that risk analysis technologies for medium-sized and giant aneurysms are currently developing quite well, small aneurysms have been poorly studied. At the same time, up to 30 % of all aneurysm ruptures are recorded specifically for medium and small aneurysms.

The aim of our work was to build a model for predicting the growth of small aneurysms based on a dynamic analysis of their morphological and hemodynamic characteristics.

Material and methods. A dynamic risk analysis of the growth of small cerebral aneurysms was performed for a group of patients from one clinical center according to computed tomography angiography. In addition to measuring the dynamics of aneurysm morphology for the studied patients, vascular tree reconstruction was also performed in the ITK Snap program and cerebral hemodynamics was calculated for 19 patients in the ANSYS CFX 2020R2 software package.

Results and discussion. During the study, an array of long-term follow-up data was obtained for patients with small cerebral aneurysms. Based on it, a logistic regression model was built, which showed area under the curve 0.8. Replenishment of the sample of examined patients will improve the performance of the model, which makes it adequate for clinical use.

Conclusions. The unique data on long-term follow-up of patients with small aneurysms are presented, and the constructed model has shown its promise provided that the sample of patients is expanded

With appearance of non-invasive imaging techniques (MRI and optical coherence tomography), it has become possible to detect early degenerative changes in the central nervous system in patients with multiple sclerosis (MS) caused by demyelination, inflammation, axonal loss, usually hidden by symptoms of acute inflammation. The possibility of early diagnosis shifts the focus in the search for effective MS treatments to the agents that enhance remyelination. The inducers of the Nrf2 transcription factor signaling pathway, such as pentacyclic triterpenoids which exhibit neuroprotective properties in MS models, are of great interest in this regard. Amide of betulonic acid (ABA), a lupane triterpenoid with pronounced cytoprotective activity, was synthesized in Novosibirsk Institute of Organic Chemistry of the SB RAS, and was studied in vivo models of toxic and inflammatory genesis.

The aim of the work was to evaluate the myelin-protective properties of ABA in a model of toxic demyelination caused by cuprizon.

Material and methods. The experiment was carried out on fifty C57Bl/6 male mice 8 weeks aged. All animals, except intact group, received 0.3 % aqueous solution of cuprizon instead of drinking water. ABA was administered orally at the doses of 50 and 100 mg/kg five times a week for 8 weeks at the same time of the cuprizone drinking. Control animals received a water-tween mixture. The reference group was subcutaneously injected twice a week with 17b-estradiol (Sigma-Aldrich, USA) at a dose of 0.2 µg per mouse in mineral oil (0.1 ml). The intact group was not manipulated. The myelin-protective effect was evaluated versus control as the changes in the area of the corpus callosum of the brain, which was determined on T2-weighted images using MRI on an ultra-high-field 11.7 T BioSpec 117/16 USR tomograph (Bruker BioSpin, FRG). Before MRI, the animals were anesthetized with a mixture of oxygen and isoflurane (200 ml/min, 1.5 % isoflurane).

Results and their discussion. It is found that 8-week exposure to cuprizon causes a 60 % decrease in the area of the corpus callosum in the control group relative to intact mice. Administration of ABA at a dose of 50 mg / kg reduces myelin loss by 33 % (p<0.001), and at a dose of 100 mg / kg – by 20 % (p < 0.01) compared with the control. 17b-estradiol reduces the demyelinating effect of cuprizon by 17 % (p < 0.05). At the same time, significant differences in the area of the corpus callosum with intact animals persist in all experimental groups. Thus, ABA and 17b-estradiol have similar myelin-protective effects, although the remyelination mechanisms of these agents are obviously different. The potential significance of ABA as a myelin-protective agent is due to its ability to activate intracellular signaling cascades associated with antioxidant and anti-inflammatory effects.

Conclusions. The data obtained indicate the ability of ABA to stimulate remyelination processes, prolonging it in conditions of chronic demyelination caused by long cuprizon exposition. The myelin-protective effect of ABA is dose-dependent, which is confirmed by literature data concerning the dose dependence of the properties of lupane triterpenoids as regulators of various intracellular signaling pathways.

Neurofeedback (NF) technologies provide an interactive mode of self-regulation of the brain motor system in stroke rehabilitation. Simultaneous presentation of signals of two modalities, hemodynamic (functional MRI) and electrophysiological (EEG), in the feedback loop allows to compensate for the limitations of each neuroimaging technology and helps to reveal the cerebral mechanisms of motor recovery.

Aim of the study was to investigate coordinated changes in fMRI signal and EEG sensorimotor rhythm power during leg movement imagination in fMRIEEG-NF sessions in a patient with stroke.

Materials and methods. A patient with right-sided hemiparesis after a 6-week stroke was trained to imagine movements of the paretic foot in five fMRI-EEG-NF sessions. The feedback scale was 2/3 determined by the level of fMRI signal amplification from the supplementary motor area (SMA) and foot representation in the motor cortex (M1F) of the left hemisphere and 1/3 by desynchronization of EEG rhythms in the mu (8–13 Hz) and beta2 (18–26 Hz) frequency bands over the central midline region (electrode Cz according to the 10–20 system).

Results and discussion. In most of the NF runs, the patient achieved desynchronization of the mu and beta2 rhythms of the EEG and an increase in the fMRI signal of the regions of interest. Activation of the left M1F was associated with desynchronization of mu rhythms, which is consistent with the literature. Suppression of both mu and beta2 bands correlated (p<0.05) with activation of the premotor cortex bilaterally, the right primary motor cortex, and the anterior thalamus and anterior insula of the right hemisphere, indicating the involvement of the intact hemisphere in motor planning and control. The predominance of activation of homologous regions of the undamaged hemisphere, as well as the involvement of the nodes of the salience network and the dorsal attention network are consistent with the hypothesis of global functional reorganization of the brain after stroke; the same is evidenced by the strengthening of the intrahemispheric functional connectivity SMA–M1F bilaterally by the end of the course.

Conclusions. For the first time, an analysis of the relationships between fMRI and EEG signals in sessions on the bimodal fMRI-EEG NF platform was performed in a patient with post-stroke foot paresis. It was shown that volitional control of the activity of M1F and SMA of the affected hemisphere also activates homologous regions of the opposite hemisphere and recruits nodes of cognitive networks, demonstrating associations with the power of the muand beta2band of EEG in the central leads.

Diseases of the brachiocephalic arteries are among the most common pathologies of the human cardiovascular system. Stenosis of the carotid bifurcation is treated surgically by performing either carotid endarterectomy or carotid artery stenting. Endarterectomy can be performed using different techniques, including variations in incision shape and the use or non-use of a patch. The advantages of each option are debated within the scientific community and depend on the arterial anatomy and other patient-specific factors.

The aim of this study was to conduct a statistical analysis of the anatomical characteristics of the common carotid artery bifurcation in order to identify relationships within and between samples of patients with stenosis and those without significant carotid artery pathology.

Results. It was demonstrated that, in the group of patients without pathology, there is a regression relationship (p < 0.007) between the diameters of the common, internal, and external carotid arteries on both the left and right sides. In the pathology group, such relationships are absent. In addition, statistically significant differences were found between the groups in the diameters of the common carotid artery (p = 0.0004) and the external carotid artery (p = 0.0003), length of the carotid sinus (p = 0.05) and common carotid artery (p = 0.01). No significant differences were identified between the groups in the diameter of the internal carotid artery, the carotid sinus, or the branching angles of the daughter arteries.

Conclusions. The results obtained may be highly useful for constructing numerical models of carotid arteries under normal conditions and in stenosis, as well as for manufacturing laboratory phantoms or for diagnostic purposes. The obtained results hold promise for application in both fundamental and applied research: in the development of numerical models of carotid arteries in normal and stenotic conditions, as well as in the design of laboratory phantoms and the refinement of diagnostic techniques for this pathology.