Monotony or mental fatigue occurs during performing low-content and monotonous work, including the work of the operator. It is accompanied by a decrease in the concentration of attention and the speed of its switching, as well as slowing in the processes of perception and motor reactions, which can lead to a loss of vigilance, self-control and the occurrence of drowsiness and, consequently, an increase in the risk of industrial injuries and accidents. In this regard, an urgent task is to develop methods for monitoring the human condition in the process of performing monotonous activities. We investigated the effect of monotony on event-related potentials (ERPs) in the visual cued Go/NoGo test. We analyzed 31-channel EEG data of 25 healthy subjects recorded before and after performing four tests with a total duration of around 1.5 hours, representing the same type of tasks with different instructions and simulating the conditions of monotonous work. After performing four tests, we observe an increase of P2 wave, decrease of the P3 Cue wave and the contingent negative variation (CNV) wave in the Cue condition, as well as the decrease of P300 wave in the NoGo condition. The results obtained in this work are assumed to reflect attenuation in proactive and reactive cognitive control during monotony and allow us to consider the P2, P3 Cue, CNV and P3 NoGo waves as possible candidates for the role of neuromarkers of monotony, which makes it promising to use these indicators in systems for monitoring the human condition during operating work.

Purpose of the study: To determine the possibility of a non-invasive evaluation of the biologically active substances (BAS) effect on the rate of a pH level restoration in a muscle after a maximum load using 1H magnetic resonance spectroscopy (MRS).Materials and methods. Creatine monohydrate and beta-alanine were taken as tested biologically active substances, used according to the manufacturer's recommendations. At the first stage, calibration curves of a pH dependence on the magnitude of chemical shifts were plotted during assigning 1H spectra of model carnosine dipeptide solutions for non-invasive determination of intramuscular pH. Further experiments were carried out on laboratory animals (mice) using a 9 T NMR spectrometer Bruker Advance III WB 400MHz WB (Bruker, Germany). In experiments on volunteers the functional test pwc170 was used for assessing the ergogenic effects of biologically active substances on rectus quadriceps femoris. The test allows to achieve the level of myocytes cytoplasm acidification with lactate, and the effectiveness of functional biologically active substances on endurance, and also the function of aerobic systems by the muscle pH rate of recovery. Detection was performed using a high-field magnetic resonance imaging scanner (Philips Healthcare, Achieva 3.0T, North Braband, The Netherlands) and two SENSE Flex-L surface ring radiofrequency coils.Results. The effect of oral intake of creatine and beta-alanine on the restoration of rectus quadriceps femoris muscle pH after an acidification of the myocytes cytoplasm with lactate was evaluated using the 1H MRS method. Reproducible results with optimal signal-to-noise ratios and width of carnosine spectral peaks were achieved in volunteers using individual protocols and 1H MRS at 3T in the quadriceps femoris. Animal experiments have highlighted the need to develop and use more accurate techniques for voxel extraction and fat suppression during in vivo 1H spectroscopy to reliably capture the chemical shifts of carnosine peaks.Conclusion. The data obtained using 1H MRS on volunteers allow us to conclude that the developed method makes it possible to non-invasively assess the effect of biologically active substances on the rate of restoration of pH level in a muscle after a critical load in real time in vivo.

INTRODUCTION: Members of the coronavirus family can affect the human central nervous system, causing various neurological complications in patients with SARS-CoV-2. Proton magnetic resonance spectroscopy (1H-MRS) seems to be a promising technique for assessing the prognosis of persistent neurological manifestations and complications, determining the completeness of a patient’s recovery during long-term follow-up. OBJECTIVE: To study changes in the metabolites profile in the brain with relation to cognitive impairment in patients with COVID-19.MATERIALS AND METHODS: 68 patients with verified COVID-19 and neurological complaints underwent a diagnostic workup, including a psychoneurological assessment and MRI of the brain with multivoxel proton magnetic resonance spectroscopy (1H-MRS), starting in the first 2 weeks from the onset of the disease. In 11 patients, a complex examination was repeated 7–8 months after the onset of the disease. The exclusion criteria were acute severe neurological symptoms, age over 65 years, artificial lung ventilation, lung CT score III–IV, as well as information about pre-Covid neuropsychiatric disorders. As a control group, earlier collected data of 10 healthy volunteers (age 30–67 years) were taken from a local database. Statistics: Intergroup differences in the ratios of metabolites peak areas determined by the 1H-MPC method were assessed using the nonparametric Mann-Whitney test with Bonferroni’s correction for multiple comparisons. Values were considered statistically significant at p<0.05. RESULTS: According to 1H-MRS, all patients with COVID-19 showed metabolic changes in the brain: a statistically significant increase in mI/Cr in the white and gray matter and a diffuse decrease in the levels of Cho/Cr in the supraventricular white matter, even in the absence of any changes in structural MRI. DISCUSSOIN: Patients were divided into three subgroups according to the severity of neurological symptoms that arose with the onset of the coronavirus infection. The most pronounced metabolic changes were found in the group with severe neurological manifestations (NM). At follow-up, a gradual recovery of the metabolite profile was noted, but in our sample group complete normalization was not achieved within the specified time frame. CONCLUSION: The obtained data indicate metabolic changes associated with SARS-CoV-2 infection, as well as the prospects for using the 1H-MPC technique in the diagnosis of neurological complications of the new coronavirus infection, including manifestations of a psychoneurological syndrome associated with COVID-19.><0.05.RESULTS: According to 1H-MRS, all patients with COVID-19 showed metabolic changes in the brain: a statistically significant increase in mI/Cr in the white and gray matter and a diffuse decrease in the levels of Cho/Cr in the supraventricular white matter, even in the absence of any changes in structural MRI.DISCUSSOIN: Patients were divided into three subgroups according to the severity of neurological symptoms that arose with the onset of the coronavirus infection. The most pronounced metabolic changes were found in the group with severe neurological manifestations (NM). At follow-up, a gradual recovery of the metabolite profile was noted, but in our sample group complete normalization was not achieved within the specified time frame.CONCLUSION: The obtained data indicate metabolic changes associated with SARS-CoV-2 infection, as well as the prospects for using the 1H-MPC technique in the diagnosis of neurological complications of the new coronavirus infection, including manifestations of a psychoneurological syndrome associated with COVID-19.

Monotony or mental fatigue occurs during performing low-content and monotonous work, including the work of the operator. It is accompanied by a decrease in the concentration of attention and the speed of its switching, as well as slowing in the processes of perception and motor reactions, which can lead to a loss of vigilance, self-control and the occurrence of drowsiness and, consequently, an increase in the risk of industrial injuries and accidents. In this regard, an urgent task is to develop methods for monitoring the human condition in the process of performing monotonous activities. We investigated the effect of monotony on event-related potentials (ERPs) in the visual cued Go/NoGo test. We analyzed 31-channel EEG data of 25 healthy subjects recorded before and after performing four tests with a total duration of around 1.5 hours, representing the same type of tasks with different instructions and simulating the conditions of monotonous work. After performing four tests, we observe an increase of P2 wave, decrease of the P3 Cue wave and the contingent negative variation (CNV) wave in the Cue condition, as well as the decrease of P300 wave in the NoGo condition. The results obtained in this work are assumed to reflect attenuation in proactive and reactive cognitive control during monotony and allow us to consider the P2, P3 Cue, CNV and P3 NoGo waves as possible candidates for the role of neuromarkers of monotony, which makes it promising to use these indicators in systems for monitoring the human condition during operating work.

We propose here a technology for constructing spatially identical flat images of the brain simultaneously in three tomographic modalities — positron emission tomography (PET), magnetic resonance imaging (MRI), and X-ray computed tomography (CT) — using the capabilities and software tools of a hybrid scanner and original software for co-registration of tomographic images obtained using dental localizer markers.

Незважаючи на зниження частоти загострень розсіяного склерозу під час симптом-модифікуючої терапії, проблема лікування рецидивів усе ще актуальна. Кожен рецидив призводить до стійкого неврологічного дефіциту і, отже, до розвитку інвалідизації. Слід зазначити, що внаслідок мінливих даних магнітно-резонансної томографії не завжди можна точно визначити активність хвороби: де­які осередки зникають або зменшуються, в той же час інші з’являються і посилюються. У цьому випадку доцільно використовувати магнітно-резонансну спектроскопію. Магнітно-резонансна спектроскопія допомагає встановити активність захворювання на ранній стадії і визначити біохімічні та нейрофізіологічні ознаки демієлінізації. У статті наведено опис складного клінічного випадку рецидиву розсіяного склерозу і оцінка метаболічної реакції на лікування за допомогою магнітно-резонансної спектроскопії.Таким чином, терапія рецидивів розсіяного склерозу дуже важлива, оскільки дає змогу відстрочити інвалідизацію. Необхідно точно оцінювати всі ризики і переваги кожного типу лікування при рецидивах.

The onset of progressive deficit in multiple sclerosis (MS) was often determined retrospectively with difficulties in diagnostic. This is a case report with subtle MS progression. Clinical and structural MRI anamnesis was complemented with multivoxel 1HMRS examination. The patient complained of the walking distance reducing, gradually increasing spasticity in the distal parts of lower extremities, unsteadiness when walking, clumsy movements. Choline and myoinositol levels were predominantly increased in the area of the cingulate gyrus versus other gray matter regions and the same picture was observed in adjacent white matter. Multivoxel 1H-MRS represents a diagnostic tool that can be very useful in complex diagnostic of MS progression. Measuring chemical-pathological changes diffusely in brain tissues may detect distinctive for progression metabolic patterns.

An algorithm for the indirect construction of coregistration functions for multimodal tomographic images of the brain obtained against the background of fiducials of dental localizers is presented. Cases with different numbers and modalities of the fiducials are considered.

Introduction. Managing patients with relapsing-remitting multiple sclerosis (RMS) remains a pressing issue. Objective. To detect the reversible metabolic changes of the brain matter in patients with clinically exacerbated RMS and to follow them up after intravenous glucocorticoid (IVGC) treatment. Materials and methods. Neurological examination and neuroimaging in the RMS patients included expanded disability status scale (EDSS) scoring, conventional brain magnetic resonance imaging (MRI), and proton nuclear magnetic resonance spectroscopy (1H-NMR spectroscopy) before and after IVGC treatment. Multivoxel 1H-NMR spectroscopy was used to assess metabolism in the centra semiovale and cingulate gyri. Results. Based on the multivoxel 1H-NMR spectroscopy, relative metabolite concentrations in the grey and white matter statistically differed within the study cohort before and after the IVGC treatment. The N-acetylaspartate/choline ratio significantly recovered and the choline/creatine ratio decreased in the anterior cingulate gyri in 27% of patients. The brainstem function score significantly improved in the metabolic response group as compared to the non-metabolic response group. Conclusion. We should study the potential predictors of RMS activity and the IVGC response to select the RMS relapses when pulse-therapy with IVGCs is definitely indicated. Spectroscopy may reveal RMS pathogenesis variability earlier than conventional MRI.

The article presents the results of the study of cognitive functions and the psychic state of HIV-infected patients. 38 patients aged 25-45 years were examined. In HIV-infected patients, dysfunctions of the central nervous system observed, which could be detected in the early stages after infection. Indicators of cognitive functions and psychic state correlated with the metabolism of the cerebral cortex, mainly with the metabolism of structures associated with executive functions. Obviously, patients of presented category have a decline in executive functions. Therefore, it is important to include psychocorrective treatment aimed at training of emotional-volitional functions, in the rehabilitation program which should also contribute to the improvement of cognitive functions and better social adaptation. The revealed changes in glucose metabolism and the content of N-acetyl aspartate were nonspecific and could be caused by a combination of the direct effect of the virus on the brain tissue, psychogenic and premorbid factors. Most likely, the existing premorbid features enhanced by the toxic effects of HIV and severe psycho-emotional stress associated with obtaining information about infection.

Different approaches to the localization of invisible point landmarks on multi-modal images of the brain with the help of external markers that are fixed dentally on the patient’s skull are considered. Localization of landmarks is implemented through the calculation of the transformation of the соregistration of images. A solution for the case of non-identical monomodal markers is obtained.

There was made an attempt to link interdisciplinary research methodically, from clinical diagnostic techniques, modern instrumental, laboratory and basic research to their implementation in practice. The experience of several partner groups studying the brain in HIV infection was analyzed and summarized. It was based on an interdisciplinary approach, the goals and authorities of infectious disease specialists, psychiatrists, neurologists, radiologists, laboratory doctors, clinical examination algorithm, the role of history and interview, express-diagnostic of cognitive functions, specialized psychiatric, neurological diagnosis, conclusion of clinical psychologists, indications for radiology methods. The choice and analysis of radiological and instrumental methods, the volume and structure of laboratory methods of central nervous system study were justified. The role of molecular genetic studies of HIV in blood and cerebrospinal fluid, the identification of drug-resistant forms of the virus was determined when choosing the therapy.

Introduction. Modern neuroimaging methods allow to evaluate in vivo biochemical processes in the brain. Such methods include magnetic resonance spectroscopy (MRS) and positron emission tomography (PET). While PET is the “golden standard” in assessing the brain functional state and is widely used in neurodegenerative diseases, the diagnostic value of MRS remains undefined due to the inconsistency of the results obtained in different studies. At the same time, MRC allows obtaining information on the content of many metabolites in living tissues, including N-acetyl aspartate (NAA), which is considered to be a surrogate marker of neuronal integrity, choline (Cho), associated with membrane metabolism, Cr - energy metabolism, etc. The aim of this study is to compare MRS and PET data in patients with Parkinson’s disease (PD).Materials and methods. Twenty-six patients with PD stages I to III according to the Hoehn and Yahr Scale and age-matching control group of neurologically and cognitively intact people were examined. All patients underwent neurological examination, a multivoxel MRS of the supraventricular region, including white and gray matter, and PET with 18F-fluorodeoxyglucose (FDG) to assess cerebral metabolic rate of glucose (CMRglu).Results. Decrease of NAA/Cr and NAA/Cho in the white matter in the left hemisphere was revealed in PD group compared to control, with the NAA/Cr ratio negatively correlating with the stage of the disease of the Hoehn and Yahr Scale. The NAA content in the white matter and the cingulate cortex positively correlated with CMRglu in Brodmann fields 5–7, 8–10, 22, 23, 46. At the same time, Cho/Cr ratio negatively correlated with CMRglu in the cortical areas associated with the development of cognitive impairment in PD (Brodman areas 9, 10, 39, 47).

Objectives. Magnetic resonance spectroscopy (MRS) allows the contents of many metabolites in living tissues to be assessed. There is a good number of studies analyzing MRS data in Alzheimer’s disease (AD), though their results are contradictory. In this regard, there is value in comparing MRS data with fluorodeoxyglucose (FDG) positron emission tomography (PET) results, which assess the functional state of nervous tissue. The present study provides a comparison of MRI scan data in AD and moderate cognitive impairment (MCI) with the characteristics of cerebral glucose metabolism assessed from FDG-PET data. Materials and methods. Multivoxel proton MRS of the supraventricular region was carried out in patients with AD (n = 16) and MCI (n = 14). The following metabolite ratios were determined: NAA/Cr, Cho/Cr, and NAA/Cho (NAA is N-acetylaspartate, Cr is creatine, and Cho is choline). Patients underwent neurological investigation, assessment of cognitive status, and PET scans with FDG. Results. Patients with AD showed decreases in NAA/Cr and Cho/Cr in the white matter of the medial cortex of the supraventricular areas of both hemispheres. The MCI group showed a decrease in the NAA/Cr ratio in only one area of the white matter of the left hemisphere, adjacent to the parietal cortex. Positive correlations were found between NAA/Cr and Cho/Cr with measures of cognitive status and with the rate of glucose metabolism measured from PET data in the frontal, parietal, and temporal areas and the cingulate cortex. Conclusions. The decrease in the NAA/Cr ratio in the supraventricular white matter and the medial cortex in AD and the correlation of this parameter with cognitive test results and cerebral glucose metabolism constitute evidence that it may have diagnostic value, reflecting the severity of cognitive impairments. Assessment of the NAA/Cr ratio should be carried out with consideration of the fact that dementia alters the concentrations of both metabolites (NAA and Cr).

The article demonstrates the first Russian experience of prenatal proton magnetic resonance spectroscopy (1Н MRS) of the brain. The results of the study are analyzed, the metabolic changes during the gestation period is evaluated. Neuroimaging methods of assessing brain metabolism may play a role in the diagnosis and prognosis of some perinatal neurological disorders, that is why the information about normal cerebral metabolic processes is extremely important. Prenatal 1Н MRS of the brain is an informative, non invasive diagnostic method that is performed complementary to MRI and provides unique information about the cerebral biochemical composition. Brain metabolic changes may precede structural, e.g. the appearance of changes in the spectrograms may outgo the changes in traditional MRI, therefore, the method may be useful in the early detection of a pathology. Early detection of abnormal metabolic brain processes may be helpful in identifying future potential therapeutic strategies.

A method using modeling on a human head phantom to evaluate the total targeting error of a stereotactic instrument to deep targets in patient’s brain is presented. The means of targeting the instrument to intracerebral aiming points was a Medtronic StealthStation S7 frameless navigation system combined with a Philips Achieva 3 T MRI scanner and a Philips Gemini TF PET/CT scanner.

The quality of the signal received from metabolites in 1H-magnetic resonance spectroscopy (MRS) directly depends on physical parameters of the impulse sequence used, namely on Time of Echo (TE). We compare MRS (Achieva 3T PRESS 1H-MRS (TE = 53 and 144 ms, TR = 2000 ms) data acquired in supraventricular white matter and medial cortex at two various TE (53 and 144 ms) for patients with the multiple sclerosis (25 patients with the confirmed diagnosis of relapsing-remitting multiple sclerosis and 20 patients with the diagnosis of secondary progressive multiple sclerosis) and control group (21 healthy volunteers, comparable on age), to evaluate advantages and disadvantages of these two Echo Time in clinical practice.

HIV-associated neurocognitive disorders are on the second place after immune system injury in HIV infection. Despite the large amount of studies, their mechanisms remain unclear especially in the subclinical stage. The purpose of our research was to study changes of brain functional state in HIV patients in different stages of the disease and revealing the early and probably prognostic features (characteristics) of subclinical neurocognitive disorders on the basis of combined analysis of the positron emission tomography (PET) and magnetic resonance spectroscopy (MRS). The obtained data demonstrated local metabolic disturbances in gray and white matter in the early stages of HIV infection. These findings raise the question about the early implication of the highly active anti-retrovirus therapy (HAART) and neuroprotectors. The abundance of the metabolic changes increases with the progression of HIV clinical symptoms. Revealed characteristics of the glucose metabolic pattern in HIV patients and threshold values of the basic metabolites ratios in MRS could be used as a predictors of the further neurocognitive disorders.