264 research outputs found

    Genetic correlations between brain volumes and the WAIS-III dimensions of verbal comprehension, working memory, perceptual organization, and processing speed

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    We recently showed that the correlation of gray and white matter volume with full scale IQ and the Working Memory dimension are completely mediated by common genetic factors (Posthuma et al., 2002). Here we examine whether the other WAIS III dimensions (Verbal Comprehension, Perceptual Organization, Processing Speed) are also related to gray and white matter volume, and whether any of the dimensions are related to cerebellar volume. Two overlapping samples provided 135 subjects from 60 extended twin families for whom both MRI scans and WAIS III data were available. All three brain volumes are related to Working Memory capacity (r = 0.27). This phenotypic correlation is completely due to a common underlying genetic factor. Processing Speed was genetically related to white matter volume (

    Диагностика заболеваний сердечно-сосудистой системы и ишемии миокарда с помощью магниторезонансной визуализации с контрастным усилением

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    Показана возможность выявления патологических изменений в миокарде (инфаркт, ишемия) и сосудистой системе (стеноз) с помощью магниторезонансной визуализации с контрастным усилением.The possibility to reveal pathological changes in the myocardium (infarction, ischemia) and vascular system (stenosis) using magnetic resonance imaging with contrast enhancement is shown

    Labyrinthine Turing Pattern Formation in the Cerebral Cortex

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    I propose that the labyrinthine patterns of the cortices of mammalian brains may be formed by a Turing instability of interacting axonal guidance species acting together with the mechanical strain imposed by the interconnecting axons.Comment: See home page http://lec.ugr.es/~julya

    Brain Plasticity and Intellectual Ability Are Influenced by Shared Genes

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    Although the adult brain is considered to be fully developed and stable until senescence when its size steadily decreases, such stability seems at odds with continued human (intellectual) development throughout life. Moreover, although variation in human brain size is highly heritable, we do not know the extent to which genes contribute to individual differences in brain plasticity. In this longitudinal magnetic resonance imaging study in twins, we report considerable thinning of the frontal cortex and thickening of the medial temporal cortex with increasing age and find this change to be heritable and partly related to cognitive ability. Specifically, adults with higher intelligence show attenuated cortical thinning and more pronounced cortical thickening over time than do subjects with average or below average IQ. Genes influencing variability in both intelligence and brain plasticity partly drive these associations. Thus, not only does the brain continue to change well into adulthood, these changes are functionally relevant because they are related to intelligence. Copyright©2010 the authors

    Гераклиты – карбонатные образования газовых источников и грязевых вулканов миоцена

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    Морфологические признаки, минералогия, геохимия и состав газовой фракции гераклитов подтвердили их генетическую общность с современными карбонатными образованиями метановых источников и грязевых вулканов Черного моря. Присутствие в гераклитах битумов, метана и этана может служить индикатором наличия нефти и газа на Гераклейском полуострове и прилегающему к нему шельфе.Морфологічні ознаки, мінералогія, геох!мія i склад газової фракцїї гераклитів підтвердили їх генетичну спільність із сучасними карбонатними утвореннями метанових джерел i грязьових вулканів Чорного моря. Присутність у гераклітах бітумів, метану i етану може слугувати як індикатор наявності нафти й газу на Гераклейськом niвocтpoвi i прилеглому до нього шельфі.Morphological attributes, mineralogy, geochemistry and structure of gas fraction Geraklit have confirmed their proximity to modern carbonate formations of methane sources and mud volcanoes in the Black sea. Presence of bitumen, methane and ethane in Geraklites serves as indicator of occurence of oil fields and gas on the Geraklejskij peninsula and adjoining to them a shelf

    Genetic contributions to human brain morphology and intelligence

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    Variation in gray matter (GM) and white matter (WM) volume of the adult human brain is primarily genetically determined. Moreover, total brain volume is positively correlated with general intelligence, and both share a common genetic origin. However, although genetic effects on morphology of specific GM areas in the brain have been studied, the heritability of focal WM is unknown. Similarly, it is unresolved whether there is a common genetic origin of focal GM and WM structures with intelligence. We explored the genetic influence on focal GM and WM densities in magnetic resonance brain images of 54 monozygotic and 58 dizygotic twin pairs and 34 of their siblings. For genetic analyses, we used structural equation modeling and voxel-based morphometry. To explore the common genetic origin of focal GM and WM areas with intelligence, we obtained cross-trait/cross-twin correlations in which the focal GM and WM densities of each twin are correlated with the psychometric intelligence quotient of his/her cotwin. Genes influenced individual differences in left and right superior occipitofrontal fascicle (heritability up to 0.79 and 0.77), corpus callosum (0.82, 0.80), optic radiation (0.69, 0.79), corticospinal tract (0.78, 0.79), medial frontal cortex (0.78, 0.83), superior frontal cortex (0.76, 0.80), superior temporal cortex (0.80, 0.77), left occipital cortex (0.85), left postcentral cortex (0.83), left posterior cingulate cortex (0.83), right parahippocampal cortex (0.69), and amygdala (0.80, 0.55). Intelligence shared a common genetic origin with superior occipitofrontal, callosal, and left optical radiation WM and frontal, occipital, and parahippocampal GM (phenotypic correlations up to 0.35). These findings point to a neural network that shares a common genetic origin with human intelligence

    Sphingosine 1-phosphate receptor 5 mediates the immune quiescence of the human brain endothelial barrier

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    BACKGROUND: The sphingosine 1-phosphate (S1P) receptor modulator FTY720P (Gilenya®) potently reduces relapse rate and lesion activity in the neuroinflammatory disorder multiple sclerosis. Although most of its efficacy has been shown to be related to immunosuppression through the induction of lymphopenia, it has been suggested that a number of its beneficial effects are related to altered endothelial and blood–brain barrier (BBB) functionality. However, to date it remains unknown whether brain endothelial S1P receptors are involved in the maintenance of the function of the BBB thereby mediating immune quiescence of the brain. Here we demonstrate that the brain endothelial receptor S1P(5) largely contributes to the maintenance of brain endothelial barrier function. METHODS: We analyzed the expression of S1P(5) in human post-mortem tissues using immunohistochemistry. The function of S1P(5) at the BBB was assessed in cultured human brain endothelial cells (ECs) using agonists and lentivirus-mediated knockdown of S1P(5). Subsequent analyses of different aspects of the brain EC barrier included the formation of a tight barrier, the expression of BBB proteins and markers of inflammation and monocyte transmigration. RESULTS: We show that activation of S1P(5) on cultured human brain ECs by a selective agonist elicits enhanced barrier integrity and reduced transendothelial migration of monocytes in vitro. These results were corroborated by genetically silencing S1P(5) in brain ECs. Interestingly, functional studies with these cells revealed that S1P(5) strongly contributes to brain EC barrier function and underlies the expression of specific BBB endothelial characteristics such as tight junctions and permeability. In addition, S1P(5) maintains the immunoquiescent state of brain ECs with low expression levels of leukocyte adhesion molecules and inflammatory chemokines and cytokines through lowering the activation of the transcription factor NFκB. CONCLUSION: Our findings demonstrate that S1P(5) in brain ECs contributes to optimal barrier formation and maintenance of immune quiescence of the barrier endothelium
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