Сопоставление фМРТ-реакций мозга здоровых людей при активных, пассивных и воображаемых движениях рукой

Objective: identify the structural features of the brain provision during motor loads of different complexity in healthy subjects. Material and methods. Comparison of fMRI cerebral reactions (individual and group) while active, passive and imagined right or left hand movement were analyzed in 20 right-handed healthy subjects by using paired t-test. Results. During active movements to clenching-unclenching the fingers motor fMRI responses were the more local and reproducible in comparison the bust fingers ones. This fact allows us to recommend this motor task as the most adequate at study of patients with cerebral disorders. The lower intensity of cortical responses and the more activation of subcortical structures was observed during left hand movement in comparison right hand one. During passive movements was observed the low volume of cerebral activation especially in cerebellum and primary motor cortex in comparison active ones. The main cortex fMRI response topography was similar while both active and passive tasks that allowed to use passive paradigm for patients with motor disorders and disturbance of consciousness. During imagined hand movements changes dramatically interplay of activated cerebral structures in comparison real movements: fMRI responses in the sensory-motor area and cerebellum were attenuated while activation of frontal zones and structures of ipsilateral hemisphere was increased. Conclusion. Comparative analysis of fMRI responses during active, passive and imagined hand movements showed that structural specificity of cerebral activity were determined by complexity of motor paradigms and by different including of motor and cognitive programs in their realization.Цель исследования: выявление особенностей структурного обеспечения работы мозга здоровых людей при двигательных нагрузках разной сложности. Материал и методы. У 20 здоровых праворуких людей проведена сравнительная оценка индивидуальных и групповых фМРТ-ответов (3Т) при активном, пассивном и воображаемом движении правой или левой рукой с использованием парного t-теста. Результаты. Выявлена большая локальность и воспроизводимость фМРТ-ответов при сжимании пальцев в кулак по сравнению с перебором пальцев, что позволяет рассматривать эту двигательную нагрузку как наиболее адекватную при исследовании больных с церебральной патологией. При работе левой рукой отмечается меньшая по сравнению с правой рукой интенсивность корковых ответов и большая активация подкорковых структур. При пассивной двигательной нагрузке по сравнению с активно выполняемым движением отмечается снижение объема активации мозга, наиболее резко выраженное в мозжечке и первичной моторной коре. Значительное сходство топографии основного коркового фМРТ-ответа при этих двигательных пробах позволяет рекомендовать использование пассивной двигательной парадигмы у больных с двигательными расстройствами и нарушением сознания. При воображаемых движениях по сравнению с реальными резко меняется соотношение активируемых структур мозга: отмечается ослабление фМРТ-ответов, наиболее резко выраженное в мозжечке и сенсомоторной области, при нарастании активации лобных отделов и структур ипсилатерального полушария. Выводы. Сравнительный анализ фМРТ ответов при выполнении разных двигательных задач позволил установить, что структурные особенности их обеспечения определяются степенью сложности исследуемых двигательных парадигм и разным включением моторных и когнитивных программ в их реализацию

Диффузионно-куртозисная МРТ в диагностике злокачественности глиом головного мозга

Purpose. To assess the diagnostic efficacy of diffusion kurtosis inaging in grading of brain gliomas. Material and methods. Absolute and normalized to the contralateral normal appearing white matter values of diffusion tensor parameters (mean, axial and radial diffusivities, fractional and relative anisotropies) and diffusion kurtosis parameters (mean, axial and radial kurtosis, kurtosis anisotropy) of tumors were compared in the most malignant solid parts of 27 (44%) low grade gliomas, 14 (23%) grade-III and 20 (33%) grade-IV gliomas (p < 0.05 significance level, Kolmogorov-Smirnov test). Results. Absolute and normalized values of all diffusion parameters (except of absolute fractional and relative anisotropies) were significantly different between high and low grade gliomas, and maximal sensitivity and specificity were found for normalized values of mean kurtosis (85,19% and 85,29%) and radial kurtosis (85,19% and 85,29%). Absolute and normalized values of all diffusion parameters (except of absolute and normalized values of fractional and relative anisotropies) differed significantly among grade-III and grade-IV gliomas, and maximal sensitivity and specificity were found for absolute mean kurtosis (92.86% and 90.00%). Only normalized values of mean, axial and radial kurtosis were significantly different between low grade and grade-III gliomas, and maximal sensitivity and specificity were found for normalized values of mean kurtosis (77.78% and 78.57%) and axial kurtosis (77.78% and 78.57%). Conclusion. Diffusion kurtosis imaging demonstrated a promising potential to differentiate among glioma grades. Kurtosis parameters better differed between gliomas grades compared with diffusion tensor parameters.Цель исследования: оценить возможности диффузионно-куртозисной МРТ в диагностике злокачественности глиом. Материал и методы. В исследование включен 61 пациент (27 (44%) глиом низкой, 14 (23%) глиом III и 20 (33%) глиом IV степени злокачественности). Абсолютные и нормализованные параметры диффузионного тензора (средняя, аксиальная и радиальная диффузия, фракционная и относительная анизотропия) и диффузионного куртозиса (средний, аксиальный и радиальный куртозис, куртозисная анизотропия) были сравнены между наиболее злокачественными участками глиом различной степени злокачественности (p < 0,05, тест Колмогорова-Смирнова). Результаты. Между глиомами высокой и низкой степени злокачественности все диффузионные параметры, кроме абсолютных фракционной и относительной анизотропии, отличались статистически значимо, а максимальные чувствительность и специфичность были получены для нормализованных среднего куртозиса (85,19 и 85,29%) и радиального куртозиса (85,19 и 85,29%). Между глиомами III и IV степени злокачественности все диффузионные параметры, кроме абсолютных и нормализованных значений фракционной и относительной анизотропии, отличались статистически значимо, а максимальные чувствительность и специфичность были получены для абсолютного среднего куртозиса (92,86 и 90,00%). Между глиомами III и глиомами низкой степени злокачественности статистически значимо отличались нормализованные средний, аксиальный и радиальный куртозис, а максимальные чувствительность и специфичность были получены для нормализованных среднего куртозиса (77,78 и 78,57%) и аксиального куртозиса (77,78 и 78,57%). Заключение. В дифференциации между группами параметры диффузионного куртозиса показали более точные результаты по сравнению с параметрами диффузионного тензора

Comparison of Gross Pathology between Classical and Recombinant Lumpy Skin Disease Viruses

The pathology caused by three different isolates of lumpy skin disease virus, classical field cluster 1.2 strain Dagestan/2015, recombinant vaccine-like cluster 2.1 strain Saratov/2017, and cluster 2.2 strain Udmurtiya/2019, in cattle was compared from experimental infections. The infection of cattle was performed using intravenous administration of 2 mL of 105 TCID50/mL of each specific LSDV. Both classical and recombinant forms of LSDV cause pathological changes in the skin and lymph nodes, as well as the trachea and lungs. Due to circulatory disorders in the affected organs, multiple areas of tissue necrosis were observed, which, with the resurgence of secondary microflora, led to the development of purulent inflammation. Observed pathological changes caused by the recombinant vaccine-like strain Udmurtiya/2019 were characterized by a more pronounced manifestation of the pathoanatomical picture compared to the classical field strains Dagestan/2015 and Saratov/2017. Interestingly, Dagestan/2015 and Udmurtiya/2019 caused damage to the lymph nodes, characterized by serous inflammation and focal purulent lymphadenitis caused by purulent microflora. “Saratov/2017” did not cause pathology in the lymph nodes. All LSDVs were virulent and caused pathology, which was not distinguishable between viruses. This data set will serve as the experimentally validated basis for the comparative examination of novel LSDV strains in gross pathology

A Recombinant Vaccine-like Strain of Lumpy Skin Disease Virus Causes Low-Level Infection of Cattle through Virus-Inoculated Feed

Since 1989, lumpy skin disease of cattle (LSD) has spread out of Africa via the Middle East northwards and eastwards into Russia, the Far East and South-East Asia. It is now threatening to become a worldwide pandemic, with Australia possibly next in its path. One of the research gaps on the disease concerns its main mode of transmission, most likely via flying insect vectors such as biting flies or mosquitoes. Direct or indirect contact transmission is possible, but appears to be an inefficient route, although there is evidence to support the direct contact route for the newly detected recombinant strains first isolated in Russia. In this study, we used experimental bulls and fed them via virus-inoculated feed to evaluate the indirect contact route. To provide deeper insights, we ran two parallel experiments using the same design to discover differences that involved classical field strain Dagestan/2015 LSDV and recombinant vaccine-like Saratov/2017. Following the attempted indirect contact transmission of the virus from the inoculated feed via the alimentary canal, all bulls in the Dagestan/2015 group remained healthy and did not seroconvert by the end of the experiment, whereas for those in the Saratov/2017 recombinant virus group, of the five bulls fed on virus-inoculated feed, three remained clinically healthy, while two displayed evidence of a mild infection. These results provide support for recombinant virus transmission via the alimentary canal. In addition, of particular note, the negative control in-contact bull in this group exhibited a biphasic fever at days 10 and 20, developed lesions from day 13 onwards, and seroconverted by day 31. Two explanations are feasible here: one is the in-contact animal was somehow able to feed on some of the virus-inoculated bread left over from adjacent animals, but in the case here of the individual troughs being used, that was not likely; the other is the virus was transmitted from the virus-fed animals via an airborne route. Across the infected animals, the virus was detectable in blood from days 18 to 29 and in nasal discharge from days 20 to 42. Post-mortem and histological examinations were also indicative of LSDV infection, supporting further evidence for rapid, in F transmission of this virus. This is the first report of recombinant LSDV strain transmitting via the alimentary mode