Alzheimer's disease (AD) is the most common neurodegenerative disease that causes dementia. Olfactory dysfunction is detected at preclinical stage of this disease, this is important for the early appointment of therapy. The smell identifcation process involves the olfactory and orbitofrontal cortex, mediobasal structures of the temporal region, including the entorhinal cortex and hippocampus, which makes it extremely sensitive to neurodegeneration, especially of the Alzheimer's type. In patients at risk of developing AD (for example, carriers of the APOE4 genotype), patients with mild cognitive impairment and subjective cognitive decline also have olfactory dysfunction, which increases with the progression of cognitive defcit. This article presents the proposed mechanisms of hyposmia development in patients with Alzheimer's disease, the main methods of its study, such as olfactory tests, evoked olfactory potential, MRI and functional MRI, as well as data from population studies of recent years.

The aim of the study. To study the peculiarities of responding to stress, the stress resistance and adaptation of older men and women with chronic brain ischemia, as well as the stressboard effect of Mexidol.
Material and methods. 124 patients aged 60–74 years old are surveyed: 72 men and 52 women (average age, respectively, 65.3 ± 0.4 and 64.7 ± 0.7 years) with Chronic Brain Ischemia I–II stage against the background of arterial hypertension and its combinations with atherosclerosis of cerebral vessels. The level of psychosocial stress was determined on the Holmes-Ray scale. Features of the response of patients to stress was studied using the methodology Scale of Psychological Stress PSM-25 and S. Rogenzweig. Stress resistance was investigated using S. Kuhlen's stress resistance self-resistant test and Villianson. The level of anxiety was determined using a scale of Ch.D. Spilberger and Yu.L. Khanin, depressed – backup questionnaire. The type of adaptation reactions was studied in the leukocyte blood formula on the percentage ratio of lymphocytes and segmented neutrophils, taking into account the representation of other formed elements.
Results. The level of stress in older women with Chronic Brain Ischemia was higher than in men. The predominance of the intrinsic orientation of the reaction to stress and resolving the type of response to men, and the extrapunitive or self-defense type among women, which may indicate the largerness of the latter. The level of stress resistance was lower in women than in men, which correlated with higher indicators of situational anxiety. Adverse adaptation reactions were more often registered in women than in men. The course of treatment with Mexidol of elderly patients with chemical leads to a decrease in the severity of subjective and objective symptoms, alarming disorders, increases the stress resistance and adaptive capabilities of the body, which is confrmed by an increase in the number of persons with favorable adaptation reactions. The high effciency and safety of sequential therapy with Mexidol (injections, then the tableted form of Mexidol Forte 250) is shown.

The prevalence of cognitive impairment in COVID-19 ranges from 59 to 65 per cent. Such variability may be associated with age and comorbidity. Arterial hypertension, diabetes mellitus, atherosclerosis are the most common comorbid conditions in patients with COVID-19. The cohort of patients with hypertension and diabetes is aged 50 and over, which suggests that age is the most important reason for the difference in the clinical picture of cognitive impairment. To date, there are no clinical guidelines for the management of patients with cognitive impairment and COVID-19, which leads to the use of various drugs, often symptomatic, increasing the risk of polypharmacy. A differentiated approach to therapy should be based on the rule of using drugs with pleiotropic effects and proven effcacy, such as Duzofarm and Nimopin.

Diabetes mellitus (DM) causes damage to various body systems, including the peripheral nervous system. The main variants of peripheral nerve damage in diabetes mellitus are considered. Information on the development of this kind of lesion, in particular, on the formation of neuropathic pain syndrome, is given. The therapeutic possibilities of drugs from various pharmacological groups for the treatment of patients with neurological complications of diabetes are analyzed.

A large number of patients are taking triptans due to ineffectiveness or contraindications to the use of non-steroidal anti-inflammatory drugs.

Aim. Study of the effcacy and safety of Zolmitriptan-SZ, as well as its comparative analysis with other drugs for the relief of migraine attacks based on patient self-reports.

Materials and methods. In an open, uncontrolled post-marketing observational study of the effcacy and safety of Zolmitripan-SZ for the relief of migraine attacks, 50 patients with migraine were included. All patients were given questionnaires to collect demographic and health information, as well as a diary for two migraine attacks.

Results. The average age of the participants was 40.3 ± 8.5 years (89.5 % were women, 10.5 % were men). After 1 hour, the pain stopped completely in 26.4 % of attacks, after 2 hours – in 78.0 %. Taking into account the return of headache in some patients, after 24 hours 65.9% patients were headache-free. There was also a signifcant reduction in the prevalence of nausea and photo-, phonophobia. Patients reported good effect in 59.6% of attacks and excellent effect in 24.7% of attacks.

Conclusion. Conclusion: Zolmitriptan SZ provides safe and effective migraine attack relief.

The aim of this study was evaluating the effect of the level attention and delayed reproduction on the quality of life in patients with cerebrovascular disease while taking various doses of cholecalciferol. 146 patients were examined, the average age of which was 59.8 ± 12.7 years. All patients were divided into three groups, depending on the dose of cholecalciferol administration. During the study, participants were assessed for the level of 25(OH) D, a neuropsychological examination and a study of the quality of life. Against the background of taking cholecalciferol at a dosage of 4000 IU per day, the level of 25(OH)D in blood serum signifcantly increased by 64.4 [12.5; 124.7] per cent (p < 0.001), and when taking 8000 IU per day – 131.8 [19.5; 298.4] per cent (p < 0.001) and its average value in the group reached an adequate level and amounted to 34.26 ± 11.22 ng/ml. In patients with cerebrovascular disease, the assessment of cognitive functions most often revealed violations in the assessment of delayed reproduction and attention. It was found that attention and delayed reproduction have a signifcantly signifcant relationship with most indicators in quality of life. Against the background of cholecalciferol therapy, a signifcantly signifcant improvement in attention and delayed reproduction was obtained when evaluated on neuropsychological scales, and there was also a signifcantly signifcant improvement in the quality of life when evaluated on the SF-36 questionnaire scale. Our study showed that the administration of cholecalciferol can improve the quality of life in patients with cerebrovascular disease.

The aim. To systematize contemporary concept about the structural and functional organization of the central nervous system (CNS) and the importance of developing the concept of the human connectome.

Main concepts. Signifcant progress in understanding the organization of the CNS in normal and in various pathological conditions was achieved after the introduction of structural and functional neuroimaging methods frst into scientifc and then into clinical practice. Recently, when studying the neuropsychiatric sphere, special attention has been paid to neural networks. One of the achievements in this feld is the construction of the human connectome – a system of structural and functional connections between various cerebral areas, the state of which is assessed using multimodal methods of functional neuroimaging. Thus, the development of brain sciences has reached a completely different level – the level of systemic psychoneurology, when the existing processes are analyzed comprehensively, with the involvement of specialists in various felds – neurology, psychiatry, neuroimaging, mathematics, etc. The human connectome is basically a biological system, therefore, although the analogy with artifcial intelligence can be traced, it does not take the frst place. The functioning of the human connectome is based on the principle of parallel, rather than sequential, information processing. Taking into account the inherent ability of the brain (at least, some of its areas) to generate spontaneous non-rhythmic oscillations, this leads to the implementation of the basic principle of the functioning of the CNS – minimizing energy consumption. In addition, the presence of spontaneous non-rhythmic oscillations (the principle of uncertainty) probably underlies the inherent human ability to intuitively think, develop new ideas. The state of the connectome in a rest is determined by past experience, the duration of external influences, and age. It affects the nature and severity of neuroplastic processes, as well as, in particular, the effectiveness of certain pharmacological drugs in a given individual. At the same time, the fnal result of neuroplastic changes may be of a different nature. It can be favorable for the body (the so-called adaptive plasticity), do not affect the body in any way, or even have a negative result (the so-called maladaptive neuroplasticity). In children, such maladaptive manifestations are less pronounced. Currently, hardware methods of influencing the connectome are being actively studied. For example, it was shown that the structure of the connectome in a rest state can change after transcranial magnetic stimulation. Further studies of this problem will open up new opportunities for studying the activity of such a complexly organized system as the brain – in normal and in various pathological conditions – and to develop more effective methods of neurorehabilitation.

The article reflects the results of studying platelet parameters in HIV-positive patients with different types of stroke.

Aim. To identify changes in laboratory parameters of a complete blood count which characterize the morphofunctional features of platelets in stroke among HIV-positive patients.

Materials and methods. 110 HIV-positive patients who received treatment for stroke in hospitals of the Tyumen region were examined. The study of blood parameters was carried out at the analyzer Sysmex XE2100 (Japan). Blood sampling was carried out on the day of patients admission.

The number of platelets and platelet indices were analyzed: MPV – mean platelet volume, PDW – platelet distribution width, PCT – plateletcrit and P-LCR – platelet large cell ratio. The control group consisted of 117 patients. The signifcance of the differences was determined at the twotailed signifcance level of p < 0.05.

Results. There was a signifcant decrease in the number of platelets (p < 0.05), in average, on 34.3% among patients with hemorrhages and HIV infection. Among patients with ischemic stroke this decrease was less pronounced (p = 0.05). A signifcant decrease in plateletcrit was established among patients with intracranial hemorrhages, while it did not change signifcantly among patients with cerebral infarction. During evaluation of other platelet parameters, no signifcant differences were found between patients in experimental and control groups. The coeffcient of giant platelets prevailed by one and a half times in patients with hemorrhages associated with HIV infection, which turned out to be beyond the statistical signifcance.

Conclusion. The presence of HIV infection leads to a more pronounced, reliable decrease in the number of platelets and plateletcrit among patients that have acute phase of the development of hemorrhagic stroke than in patients with cerebral infarction. The development of intracranial hemorrhage among HIV-positive patients is characterized by an increase of blood platelets with a high volume, the level of which increased by one and a half times being beyond the statistical signifcance and having as a leading mechanism the intensifcation of platelet formation in the bone marrow.

Huntington's chorea is a hereditary disease causing progressive degeneration of the central nervous system with the damage to extrapyramidal structures: basal nuclei, striatum, subthalamic nucleus with increased activity of the central dopaminergic pathways, with the development of neurological, psychiatric, and emotional/personality disorders [1, 17]. The inheritance pattern of the disorder is autosomal dominance. The prevalence of Huntington's disease ranges from 3 to 17 cases per 100,000 population, averaging 5–7 cases per 100,000 population in Russia [2]. The development of the disease is associated with the expansion of CAG (cytosine-adenine-guanine) trinucleotide repeats in the frst exon of the HTT gene encoding the huntingtin protein. This expansion of trinucleotides (long sections of glutamine residues) leads to the selective loss of neurons that connect the striatum and the globus pallidus. This leads to a loss of inhibitory activity and an increase in the excitation impulse, which leads to uncontrolled movements.

Unfortunately, medical treatment does not slow down the progression of this disease (a lethal outcome occurs within 15–20 years). Improvement of the quality of life of people with Huntington's chorea, with the provision of medical services at an appropriate level, remains an urgent issue. This direction is especially relevant in providing dental care to patients with Huntington's chorea. Due to the pronounced hyperkinetic syndrome and compulsive movements in the muscles of the arms, trunk, neck and face, it is almost impossible to provide dental care for these patients. Currently, general anesthesia is used to enable dental intervention, but patients note that with frequent use of anesthesia, the patient's condition deteriorates, with an increase in hyperkinetic symptoms. Tetrabenazine is known to reduce the severity of hyperkinetic symptoms and is used in many countries [5].

However, in our country many specialists are not familiar with it. During the follow-up of a patient with Huntington's chorea, with the selection of a therapeutic dose of tetrabenazine, it was possible to provide three stages of dental care for the patient without the use of general anesthesia. The material presented in the article can provide useful information on the use of tetrabenazine in patients with Huntington's chorea.

In clinical practice neurologists are faced with patients' questions regarding the prognosis, however, there are no specifc guidelines devoted to this problem in neurology, despite the fact that the outcome of the disease is a clinical issue with the highest priority for both the practitioner and the patient. This article examines the approaches to discuss the prognosis of neurological disease, data on the prognosis of common neurological diseases.