Роль церебрального резерва, оцененного с помощью диффузионно-взвешенной магнитно-резонансной томографии, в определении реабилитационного потенциала острого периода ишемического инсульта
Fractional anisotropy (FA) estimated using diffusion tensor magnetic resonance imaging (dMRI) is considered as a promising biomarker in ischemic stroke (IS). The basis of this study is the assumption that the assessment of FA indices for different white matter tracts will be able to predict the main aspects of the rehabilitation potential even without determining the structural and functional bases of these influences.
Objective: to study the diagnostic significance of changes in FA indices to assess various aspects of the rehabilitation potential in acute IS.
Patients and methods. Examinations were made in 100 patients with IS and in 10 individuals without stroke and cognitive impairment. All the patients underwent dMRI and assessments of rehabilitation potential indicators on days 3 and 10 of the disease and at discharge.
Results and discussion. The indices of FA of the ipsilateral upper longitudinal and cingulum bundles, FA and the size of an infarct focus, asymmetry of FA of the cingulum bundle (rFA), corticospinal tract (at the level of the knee of the internal capsule and bridge) and the anterior limb of the internal capsule, as well as the FA of the splenium and knee of the internal capsule of the intact hemisphere are of the most value for the functional outcome of acute IS. The microstructure of these zones determines the state of most rehabilitation domains. With respect to global outcome, the integrity of the associative tracts of the affected hemisphere is more valuable than the microstructure of the intact hemisphere and rFA. The tracts of the intact hemisphere are of particular importance for the restoration of complex rehabilitation spheres, such as cognitive status and daily living and social skills, which is necessary to ensure patient independence.
Conclusion. The FA indices of the tracts under study seem to be a clinically acceptable biomarker of various aspects of the rehabilitation potential in acute IS.
The degree of mental attention in childhood and adolescence determines in the future the effectiveness of working memory (ability to store and manipulate information). Attention has been previously found to be related to the prefrontal and parietal areas of the human cortex. But the relationship between attention and white matter properties are still largely unknown. The goal of this study was to identify the relationships between attention and fractional anisotropy (FA) of diffusion MRI in bilateral superior longitudinal fasciculus (in three subdivisions SLF 1- 3), arcuate fasciculus (AF), and corpus callosum (CC) in children and adolescents. Subjects: 14 children (9-11 years) and 13 teenagers (12-15 years). During the experiments participants had to establish a match between the colors on the screen and the colors on the previous slide. The task had six difficulty levels and both performance accuracy (m-score) and reaction time (RT) were measured. There was a positive correlation for m-score and a negative correlation for RT with FA in СС (levels 1-3) in the children's group (p<0.05). On the contrary, when FA increases in the right SLF 3 (level 6), there is a decrease in m-score, and when FA increases in the left SLF 3 and AF, there is an increase in RT at 2,3,4 and 6 levels. In contrast, a decrease in RT with an increase FA of bilateral SLF 3 (level 6) and left AF (level 4) was observed for adolescents, which reflects the redistribution of the roles between fiber tracts with age. FA values of the left (level 2) and right (level 1) SLF 2 negatively correlated with mscore (p <0.05) in the same group. For females (n=13) (regardless the age), there was only a negative correlation for m-score (2,3,5 levels) and the only positive correlation for RT (level 2) with FA of the right SLF 1, left and right SLF 2, in the left SLF 3 and СС (p<0.05). For males (n=13), on the contrary, there were positive correlations between m-score and FA of the СС (1,3,4 levels) and the left SLF 1 (5 level), and inverse correlations between RT and FA for the same fibers of the white matter (1 level) (p<0,05). Interestingly, an increase in FA with age was found in males in all the components of the white matter (p<0.01), except for the СС, and in females, on thecontrary – only in the СС. Further research is needed, taking into account gender, to fully understand the influence of white matter on the development of mental attention.
Aim. To study the relationship between cerebral perfusion and severity of cerebral small vessel disease (SVD) in the context of the rehabilitation potential in acute ischemic stroke (IS).
Material and methods. 50 patients with IS and 10 persons of the control group were examined. All patients underwent standard examinations, including brain MRI with an assessment of lacunes, enlarged perivascular spaces (PVS), leukoareosis and cerebral microbleeds (CMB). Cerebral blood flow (CBF) was quantified in the middle cerebral artery territory according to ASPECTS scale by non-contrast magnetic resonance ASL-perfusion.
Results. In patients with IS, unlike the control group, a lower CBF in M3 white matter within both hemispheres and in the cortical part of M6 of the ipsilateral hemisphere is revealed. The number of lacunes in the contralateral hemisphere is related to perfusion in 8 ASPECTS areas. The number of PVS is associated with CBF in insula, lenticular nucleus, M3 of the opposite hemisphere, M6 and internal capsule of the affected hemisphere. The severity of leukoareosis correlates with CBF in 4 zones of the opposite hemisphere. The greatest number of correlations with CBF in basal ganglia was observed for CMBs of the affected hemisphere. Total severity of SVD is also associated with CBF in several areas. The severity of neurological deficiency and dynamics of patient`s mobility, functional and cognitive status correlates with CBF. Conclusion. Global perfusion status is associated with severity of SVD and rehabilitation potential in acute period of IS.
The XVI international interdisciplinary Congress "Neuroscience for medicine and psychology" continues the cycle of scientific events (High Tatras, Slovakia, 2002 and 2003; Karadag, Crimea, Ukraine, 2002 and 2003; Hurghada, Egypt, 2004, Sudak, Crimea, Ukraine, 2004-2013, Sudak, Crimea, Russia, 2014-2019), which are dedicated to the multi-faceted study of the nervous system and the use of this knowledge in medical and psychological practice. The main goal of the forum is to unite the efforts of highly qualified and young specialists of the scientific community who study the nervous system from different points of view to preserve the biological and mental health of people in the modern world. As part of the Congress, the School "Achievements of interdisciplinary neuroscience in the XXI century" is held with lectures and reports by leading scientists. The following issues will be discussed at the sessions of the Congress sections: stress and neurosis, memory, learning, thinking and consciousness, neuronal mechanisms of cognitive processes, Neurotechnology and cognitive
Adequate assessment of individual functional motor potentials is important for developing appropriate rehabilitation strategies in ischemic stroke . Microstructural changes in corticospinal tract (CST) and corpus callosum (CC) were repeatedly correlated to post-stroke outcome [2, 3]. However, relationship between them and functional recovery remains unclear. Here we investigated relationship between integrity of CST and CC assessed with diffusion tensor imaging (DTI) and brain functional state assessed with navigated transcranial magnetic stimulation (nTMS) in chronic ischemic supratentorial stroke.
Hand motor recovery prognosis in stroke patients is crucial to develop a realistic individual rehabilitation plan. The aim of this study was to perform a multimodal assessment in chronic ischemic stroke patients and to compare predictive role of corticospinal tract (CST) integrity measured by diffusion tensor imaging (DTI) and navigated TMS (nTMS), and functional condition of the motor cortex measured by functional MRI (fMRI) and multi-muscle nTMS cortical mapping for hand motor recovery.Total of 30 patients with the only chronic supratentorial ischemic stroke and various severity of hand paresis were enrolled (12 females, medium age 50,0±8,0). The assessment included fractional anisotropy FA (index, %) measurement in internal capsule (ic), cerebral peduncle (pc) and pons. Functional assessment included analysis of BOLD response induced by passive motor task, assessment of intracortical inhibition (SICI) and intracortical facilitation (ICF) phenomena in Abductor Pollicis Brevis (APB) and nTMS mapping of APB and Extensor Digitorum Communis (EDC) cortical representations in both hemispheres. A group of 14 healthy volunteers (7 females, mean age 36,6±15,2) completed fMRI and nTMS investigation. A strong correlation between clinical outcome and FA let to consider FA as an available clinical measurement for hand motor prognosis. Significantly higher disinhibition in the unaffected hemisphere (UH) in well recovered and normal SICI in the UH in poorly recovered patients allow to suppose that interhemispheric interaction might change extensively by chronic phase. A software for multi-muscle nTMS mapping was developed, though this approach need deeper exploration.
Materials of the all-Russian scientific-practical conference with international participation
Objective: Glioblastoma is a highly aggressive and invasive brain and Central Nervous System (CNS) tumor. Current treatment options do not prolong overall survival significantly because the disease is highly prone to relapse. Therefore, research to find new therapies is of paramount importance. It has been discovered that glioblastomas contain a population of cells with stem-like properties and that these cells are may be responsible for tumor recurrence.
Methods: A review of relevant papers and clinical trials in the field was conducted. A PubMed search with related keywords was used to gather the data. For example, “glioblastoma stem cells AND WNT signaling” is an example used to find information on clinical trials using the database ClinicalTrials.gov.
Results: Cancer stem cell research has several fundamental issues and uncertainties that should be taken into consideration. Theoretically, a number of treatment options that target glioblastoma stem cells are available for patients. However, only a few of them have obtained promising results in clinical trials. Several strategies are still under investigation.
Conclusion: The majority of treatments to target cancer stem cells have failed during clinical trials. Taking into account a number of biases in the field and the number of unsuccessful investigations, the application of the cancer stem cells concept is questionable in clinical settings, at least with respect to glioblastoma.
Data management and analysis is one of the fastest growing and most challenging areas of research and development in both academia and industry. Numerous types of applications and services have been studied and re-examined in this field resulting in this edited volume which includes chapters on effective approaches for dealing with the inherent complexity within data management and analysis. This edited volume contains practical case studies, and will appeal to students, researchers and professionals working in data management and analysis in the business, education, healthcare, and bioinformatics areas.
Given many developing economies depend on primary commodities, the fluctuations of commodity prices may imply significant effects for the wellbeing of children. To investigate, this paper examines the relationship between child mortality and commodity price movements as reflected by country-specific commodity terms-of-trade. Employing a panel of 69 low and lower-middle income countries over the period 1970-2010, we show that commodity terms-of-trade volatility increases child mortality in highly commodity-dependent importers suggesting a type of ‘scarce’ resource curse. Strikingly however, good institutions appear able to mitigate the negative impact of volatility. The paper concludes by highlighting this tripartite relationship between child mortality, volatility and good institutions and posits that an effective approach to improving child wellbeing in low to lower-middle income countries will combine hedging, import diversification and improvement of institutional quality.