32 research outputs found

    Corrigendum: Histological Correlates of Diffusion-Weighted Magnetic Resonance Microscopy in a Mouse Model of Mesial Temporal Lobe Epilepsy

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    In the published article, there were errors in affiliations 2 and 3. Instead of “Experimental Epilepsy Research, Department of Neurosurgery, Medical Center – University of Freiburg, Freiburg, Germany” and “Department Neurosurgery, Experimental Epilepsy Research, Medical Center, University of Freiburg, Freiburg, Germany,” they should be “Faculty of Medicine, University of Freiburg, Freiburg, Germany” and “Experimental Epilepsy Research, Department of Neurosurgery, Medical Center – University of Freiburg, Freiburg, Germany,” respectively. The authors apologize for these errors and state that this does not change the scientific conclusions of the article in any way. The original article has been updated

    Histological Correlates of Diffusion-Weighted Magnetic Resonance Microscopy in a Mouse Model of Mesial Temporal Lobe Epilepsy

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    Mesial temporal lobe epilepsy (MTLE) is the most common type of focal epilepsy. It is frequently associated with abnormal MRI findings, which are caused by underlying cellular, structural, and chemical changes at the micro-scale. In the current study, it is investigated to which extent these alterations correspond to imaging features detected by high resolution magnetic resonance imaging in the intrahippocampal kainate mouse model of MTLE. Fixed hippocampal and whole-brain sections of mouse brain tissue from nine animals under physiological and chronically epileptic conditions were examined using structural and diffusion-weighted MRI. Microstructural details were investigated based on a direct comparison with immunohistochemical analyses of the same specimen. Within the hippocampal formation, diffusion streamlines could be visualized corresponding to dendrites of CA1 pyramidal cells and granule cells, as well as mossy fibers and Schaffer collaterals. Statistically significant changes in diffusivities, fractional anisotropy, and diffusion orientations could be detected in tissue samples from chronically epileptic animals compared to healthy controls, corresponding to microstructural alterations (degeneration of pyramidal cells, dispersion of the granule cell layer, and sprouting of mossy fibers). The diffusion parameters were significantly correlated with histologically determined cell densities. These findings demonstrate that high-resolution diffusion-weighted MRI can resolve subtle microstructural changes in epileptic hippocampal tissue corresponding to histopathological features in MTLE

    Analysis of volume and topography of adipose tissue in the trunk: Results of MRI of 11,141 participants in the German National Cohort

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    This research addresses the assessment of adipose tissue (AT) and spatial distribution of visceral (VAT) and subcutaneous fat (SAT) in the trunk from standardized magnetic resonance imaging at 3 T, thereby demonstrating the feasibility of deep learning (DL)-based image segmentation in a large population-based cohort in Germany (five sites). Volume and distribution of AT play an essential role in the pathogenesis of insulin resistance, a risk factor of developing metabolic/cardiovascular diseases. Cross-validated training of the DL-segmentation model led to a mean Dice similarity coefficient of >0.94, corresponding to a mean absolute volume deviation of about 22 ml. SAT is significantly increased in women compared to men, whereas VAT is increased in males. Spatial distribution shows age- and body mass index-related displacements. DL-based image segmentation provides robust and fast quantification of AT (≈15 s per dataset versus 3 to 4 hours for manual processing) and assessment of its spatial distribution from magnetic resonance images in large cohort studies

    Impact d’une agression pĂ©riphĂ©rique localisĂ©e (traumatisme musculaire) ou systĂ©mique (sepsis) sur le systĂšme nerveux central

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    Peripheral aggression, not primarily affecting the central nervous system (CNS) by definition, can cause disabling secondary neurological sequelae whose prevention, recognition and management still remain unclear. Organ failure such as that seen in sepsis, but also peripheral injury or surgery, can sometimes lead to severe neurological sequelae. Current research shows more and more similarities in secondary neurological disorders resulting from various peripheral aggressions, both epidemiologically, clinically, but also pathophysiologically. Better specify these common characteristics would improve the recovery of patients by appropriate care with the establishment of preventive therapy. Our goal was to decipher some of these phenomena in two complementary models. In a mouse model, we specified the influence of muscle destruction in the occurrence of cognitive disorders. Tibialis anterior muscle cryolesion (a physical damage with moderate impact on general condition and complete muscle regeneration within less than one month) in the CX3CR1-GFP/+ mouse (whose microglial cells express GFP) allowed us to to demonstrate an early microglial reactivity in the whole brain (especially the hippocampus which is involved in many memory processes). By a behavioral study carried out after muscular regeneration, we showed an alteration of the short- and long term-memory. It was also characterized by a disruption of neurotrophin levels in the brain, namely an increase in brain derived neurotrophic factor (BDNF) and a decrease in nerve growth factor (NGF). In a second time, we were interested in the impact of sepsis on the CNS, in the horse. Recruitment of a clinical cohort in a specialized center allowed us to highlight many clinical and bioclinical similarities between equine and human pathology. Our results strongly suggest a similar susceptibility and responsiveness to sepsis. We also observed a significant morphological reactivity of microglia in many regions of the brain during the acute phase of sepsis. In conclusion, our results show a central reactivity of microglia in two types of peripheral aggressions (muscle trauma and sepsis) in two different species (mouse and horse). The modulation of this common cellular actor could be a preventive therapeutical strategy regarding the occurrence of secondary cognitive disorders. The two models we used have a certain scientific and technical advantage in (i) the demonstration of a modulation pathway involving microglia (mutant murine model), and (ii) the evaluation of the drug effectiveness before the setting up of clinical trials in humans (spontaneous equine pathology).Les agressions pĂ©riphĂ©riques, c'est Ă  dire ne touchant pas primairement le systĂšme nerveux central (SNC) par dĂ©finition, peuvent ĂȘtre Ă  l'origine de sĂ©quelles neurologiques secondaires invalidantes dont la prĂ©vention, la reconnaissance et la prise en charge demeurent encore aujourd'hui trĂšs incomplĂštes. Une dĂ©faillance d'organe comme celle rencontrĂ©e lors d'un sepsis, mais Ă©galement une blessure pĂ©riphĂ©rique ou une chirurgie, peuvent induire des sĂ©quelles neurologiques parfois sĂ©vĂšres. La recherche actuelle met en Ă©vidence de plus en plus de similitudes dans les troubles neurologiques secondaires issus d'agressions pĂ©riphĂ©riques variĂ©es, tant sur le plan Ă©pidĂ©miologique, clinique, mais aussi physiopathologique. Mieux prĂ©ciser ces caractĂ©ristiques communes permettrait d'amĂ©liorer la rĂ©cupĂ©ration des patients par une prise en charge adaptĂ©e avec la mise en place d'une thĂ©rapeutique prĂ©ventive. Notre objectif Ă©tait de dĂ©crypter une partie de ces phĂ©nomĂšnes dans deux modĂšles complĂ©mentaires. Dans un modĂšle murin, nous avons prĂ©cisĂ© l'influence de la destruction musculaire dans l'apparition des troubles cognitifs. La cryolĂ©sion du muscle Tibialis anterior (blessure physique avec rĂ©percussion modĂ©rĂ©e sur l'Ă©tat gĂ©nĂ©ral et rĂ©gĂ©nĂ©ration musculaire complĂšte en moins d'un mois) chez la souris CX3CR1-GFP/+ (dont les cellules microgliales expriment la GFP), nous a permis de mettre en Ă©vidence une rĂ©activitĂ© microgliale prĂ©coce dans l'ensemble de l'encĂ©phale (notamment l'hippocampe qui est impliquĂ©e dans de nombreux processus de mĂ©morisation). Par une Ă©tude comportementale rĂ©alisĂ©e aprĂšs rĂ©gĂ©nĂ©ration musculaire, nous avons montrĂ© une altĂ©ration de la mĂ©moire Ă  court et long terme. Cette derniĂšre Ă©tait Ă©galement caractĂ©risĂ©e par une perturbation des niveaux de neurotrophines dans l'encĂ©phale, Ă  savoir une augmentation du brain derived neurotrophic factor (BDNF) et une diminution du nerve growth factor (NGF). Dans un second temps, nous nous sommes intĂ©ressĂ©s Ă  l'impact du sepsis sur le SNC, chez le cheval. Le recrutement d'une cohorte clinique dans un centre spĂ©cialisĂ© nous a permis de mettre en Ă©vidence de nombreuses similitudes cliniques et biocliniques entre la pathologie Ă©quine et celle de l'homme. Nos rĂ©sultats suggĂšrent fortement une susceptibilitĂ© et une rĂ©activitĂ© au sepsis comparables. Nous avons Ă©galement observĂ© une importante rĂ©activitĂ© morphologique de la microglie dans de nombreuses rĂ©gions de l'encĂ©phale lors de la phase aigĂŒe du sepsis. En conclusion, nos rĂ©sultats montrent une rĂ©activitĂ© centrale de la microglie dans deux types d'agressions pĂ©riphĂ©riques (trauma musculaire et sepsis) chez deux espĂšces diffĂ©rentes (souris et cheval). La modulation de cet acteur cellulaire commun pourrait ĂȘtre une piste thĂ©rapeutique prĂ©ventive concernant l'apparition des troubles cognitifs secondaires Ă  ce type d'agressions. Les deux modĂšles que nous avons utilisĂ©s prĂ©sentent un avantage scientifique et technique certain (i) dans la mise en Ă©vidence d'une voie de modulation impliquant la microglie (modĂšle murin mutant), et (ii) l'Ă©valuation de l'efficacitĂ© d'une Ă©ventuelle thĂ©rapeutique mĂ©dicamenteuse avant la mise en place d'essais cliniques chez l'homme (pathologie spontanĂ©e Ă©quine)

    Descartes lector de SĂ©neca

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    HOMENAJE A DESCARTES-A finales del siglo xvi y principios del x v i i, la filosofía m oral del estoicismo conoce, en Europa, pero sobre todo en Francia, un nuevo brote de popularidad. Descartes, durante el verano de 1645, en su correspondencia con Elizabeth de Bohemia, sobre los fundamentos y los fines de la moral, aprovecha la oportunidad para instar a la joven princesa a leer la obra de Séneca: D e vita beata. El, por su parte, se comprom ete en hacerle llegar sus comentarios sobre el tratado del filósofo latino. Aunque nunca haya desarrollado tal comentario, se le da al lector comtemporáneo la posibilidad de considerar ese conjunto de nueve cartas (18 de mayo-6 de octubre de 1645), como form ando un pequeño tratado de moral comparada; a medio camino entre las famosas pero insuficientes reglas de la m oral por provisión, contenidas en el Discurso del método y las tesis, que por cierto anuncian, de Las pasiones del alm a. N os preguntamos entonces: ¿la elección de Séneca sólo habrá sido un pretexto para exponer su propia filosofía moral?; ¿porqué, en vez de acudir al dogma cristiano, Descartes recurre a una filosofía pagana, en su búsqueda de los fundamentos de la moral?; ¿por qué escoge la escuela estoica y dentro de ella, no uno de los grandes sino a Séneca?AbstractIn the late XVI century and early XVII stoic moral philosophy experienced, in Europe, but mainly in France, a renewal of popularity. During the summer of 1645, in this correspondence with Elizabeth of Bohemia, Descartes, dealing with the issue of the foundations and finality o f m orals, invite the young princess to read Seneca’s treatise: De vita beata. H e comprises himself by sending her his own comentaries upon the latin philosopher’s work. Although he never fulfilled his prom ise, we, the modern readers, are allowed to see these nine letters (May 18th-Octuber 6th 1645) as a small treatise of compared m orals, half way between the famous but insufficient rules of the provisory moral exposed in the Discourse o f the Method and the final theses, which he obviously announces there, of The Passions ofthe Soul. Weask ourselves the: Has choosing Seneca just been, to Descartes, a pretext for exposing his own m oral philosophy? Why, intead of going back to the Christian dogma, does Descartes refer to a pagan pholosophy, in his quest for the foundations of the moral? And why picking, within the wide range of ancient philosophy, the stoic school and within it not one of the great past masters but Seneca

    L’utilisation du flow dans les activitĂ©s ludiques en soins de suite et de rĂ©adaptation adulte

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    Les jeux sont utilisĂ©s par les ergothĂ©rapeutes dans la plupart des services de soins de suite et de rĂ©adaptation. Dans ce mĂ©moire, nous nous somme interrogĂ©s sur l’utilitĂ© de la thĂ©orie du flow de Csikszentmihalyi lors d’une activitĂ© ludique. Suivant une mĂ©thode clinique, nous avons rĂ©alisĂ© trois entretiens auprĂšs d’ergothĂ©rapeutes travaillant en SSR adultes et utilisant le jeu. Nous avons dĂ©terminĂ© que plusieurs Ă©lĂ©ments favorisant l’apparition du flow sont prĂ©sents dans les activitĂ©s choisies, mais que la rĂ©troaction immĂ©diate et la facilitation de la concentration sont peu exploitĂ©es. L’expĂ©rience optimale peut ĂȘtre observĂ©e et a des consĂ©quences se rapprochant de celles exposĂ©es dans la thĂ©orie du flow. Enfin, au fil du discours, nous avons relevĂ© des Ă©lĂ©ments concrets sur le rĂŽle du thĂ©rapeute lors de l’utilisation d’une activitĂ© ludique. À partir de ses Ă©lĂ©ments sur la pratique de terrain, et en nous appuyant sur la thĂ©orie, nous avons proposĂ© des actions Ă  mettre en place par l’ergothĂ©rapeute pour potientialiser l’utilisation du flow lors d’une activitĂ© ludique

    La qualification personnelle, un paradigme de la reconnaissance au travail

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    L’enjeu de cet article est de comparer deux institutions du travail, l’emploi et la qualification personnelle, du point de vue de la reconnaissance. Il s’agit de montrer que l’emploi implique une incertitude fondamentale quant Ă  la continuitĂ© de l’activitĂ©. Cette incertitude se traduit par un manque actuel ou potentiel de reconnaissance des travailleuses et des travailleurs. Au contraire, la qualification personnelle permet une continuitĂ© de la reconnaissance des travailleurs, non pas dans leur activitĂ© mais dans leurs capacitĂ©s, dans leur puissance. Il est alors essentiel de distinguer la qualification personnelle, qui permet de tĂ©moigner de la reconnaissance et du respect de toutes les personnes qui participent Ă  la production sociale, et les niveaux de qualification, qui introduisent des niveaux d’estime diffĂ©renciĂ©s.This article aims to compare two institutions of work, employment and personal qualification, from the point of view of recognition. The ambition is to demonstrate that employment involves a fundamental uncertainty about the continuity of the activity. This uncertainty translates into an actual or potential lack of recognition for workers. On the contrary, personal qualification allows a continuity of recognition to workers, not in their activity but in their capacities, in their power. Therefore, it is essential to distinguish between personal qualification, which allows us to testify recognition and respect for all the people who participate in social production, and the levels of qualification, which introduce differentiated levels of esteem

    Study of the impact of localized (muscle trauma) or systemic (sepsis) peripheral aggression on the central nervous system

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    Les agressions pĂ©riphĂ©riques, c'est Ă  dire ne touchant pas primairement le systĂšme nerveux central (SNC) par dĂ©finition, peuvent ĂȘtre Ă  l'origine de sĂ©quelles neurologiques secondaires invalidantes dont la prĂ©vention, la reconnaissance et la prise en charge demeurent encore aujourd'hui trĂšs incomplĂštes. Une dĂ©faillance d'organe comme celle rencontrĂ©e lors d'un sepsis, mais Ă©galement une blessure pĂ©riphĂ©rique ou une chirurgie, peuvent induire des sĂ©quelles neurologiques parfois sĂ©vĂšres. La recherche actuelle met en Ă©vidence de plus en plus de similitudes dans les troubles neurologiques secondaires issus d'agressions pĂ©riphĂ©riques variĂ©es, tant sur le plan Ă©pidĂ©miologique, clinique, mais aussi physiopathologique. Mieux prĂ©ciser ces caractĂ©ristiques communes permettrait d'amĂ©liorer la rĂ©cupĂ©ration des patients par une prise en charge adaptĂ©e avec la mise en place d'une thĂ©rapeutique prĂ©ventive. Notre objectif Ă©tait de dĂ©crypter une partie de ces phĂ©nomĂšnes dans deux modĂšles complĂ©mentaires. Dans un modĂšle murin, nous avons prĂ©cisĂ© l'influence de la destruction musculaire dans l'apparition des troubles cognitifs. La cryolĂ©sion du muscle Tibialis anterior (blessure physique avec rĂ©percussion modĂ©rĂ©e sur l'Ă©tat gĂ©nĂ©ral et rĂ©gĂ©nĂ©ration musculaire complĂšte en moins d'un mois) chez la souris CX3CR1-GFP/+ (dont les cellules microgliales expriment la GFP), nous a permis de mettre en Ă©vidence une rĂ©activitĂ© microgliale prĂ©coce dans l'ensemble de l'encĂ©phale (notamment l'hippocampe qui est impliquĂ©e dans de nombreux processus de mĂ©morisation). Par une Ă©tude comportementale rĂ©alisĂ©e aprĂšs rĂ©gĂ©nĂ©ration musculaire, nous avons montrĂ© une altĂ©ration de la mĂ©moire Ă  court et long terme. Cette derniĂšre Ă©tait Ă©galement caractĂ©risĂ©e par une perturbation des niveaux de neurotrophines dans l'encĂ©phale, Ă  savoir une augmentation du brain derived neurotrophic factor (BDNF) et une diminution du nerve growth factor (NGF). Dans un second temps, nous nous sommes intĂ©ressĂ©s Ă  l'impact du sepsis sur le SNC, chez le cheval. Le recrutement d'une cohorte clinique dans un centre spĂ©cialisĂ© nous a permis de mettre en Ă©vidence de nombreuses similitudes cliniques et biocliniques entre la pathologie Ă©quine et celle de l'homme. Nos rĂ©sultats suggĂšrent fortement une susceptibilitĂ© et une rĂ©activitĂ© au sepsis comparables. Nous avons Ă©galement observĂ© une importante rĂ©activitĂ© morphologique de la microglie dans de nombreuses rĂ©gions de l'encĂ©phale lors de la phase aigĂŒe du sepsis. En conclusion, nos rĂ©sultats montrent une rĂ©activitĂ© centrale de la microglie dans deux types d'agressions pĂ©riphĂ©riques (trauma musculaire et sepsis) chez deux espĂšces diffĂ©rentes (souris et cheval). La modulation de cet acteur cellulaire commun pourrait ĂȘtre une piste thĂ©rapeutique prĂ©ventive concernant l'apparition des troubles cognitifs secondaires Ă  ce type d'agressions. Les deux modĂšles que nous avons utilisĂ©s prĂ©sentent un avantage scientifique et technique certain (i) dans la mise en Ă©vidence d'une voie de modulation impliquant la microglie (modĂšle murin mutant), et (ii) l'Ă©valuation de l'efficacitĂ© d'une Ă©ventuelle thĂ©rapeutique mĂ©dicamenteuse avant la mise en place d'essais cliniques chez l'homme (pathologie spontanĂ©e Ă©quine).Peripheral aggression, not primarily affecting the central nervous system (CNS) by definition, can cause disabling secondary neurological sequelae whose prevention, recognition and management still remain unclear. Organ failure such as that seen in sepsis, but also peripheral injury or surgery, can sometimes lead to severe neurological sequelae. Current research shows more and more similarities in secondary neurological disorders resulting from various peripheral aggressions, both epidemiologically, clinically, but also pathophysiologically. Better specify these common characteristics would improve the recovery of patients by appropriate care with the establishment of preventive therapy. Our goal was to decipher some of these phenomena in two complementary models. In a mouse model, we specified the influence of muscle destruction in the occurrence of cognitive disorders. Tibialis anterior muscle cryolesion (a physical damage with moderate impact on general condition and complete muscle regeneration within less than one month) in the CX3CR1-GFP/+ mouse (whose microglial cells express GFP) allowed us to to demonstrate an early microglial reactivity in the whole brain (especially the hippocampus which is involved in many memory processes). By a behavioral study carried out after muscular regeneration, we showed an alteration of the short- and long term-memory. It was also characterized by a disruption of neurotrophin levels in the brain, namely an increase in brain derived neurotrophic factor (BDNF) and a decrease in nerve growth factor (NGF). In a second time, we were interested in the impact of sepsis on the CNS, in the horse. Recruitment of a clinical cohort in a specialized center allowed us to highlight many clinical and bioclinical similarities between equine and human pathology. Our results strongly suggest a similar susceptibility and responsiveness to sepsis. We also observed a significant morphological reactivity of microglia in many regions of the brain during the acute phase of sepsis. In conclusion, our results show a central reactivity of microglia in two types of peripheral aggressions (muscle trauma and sepsis) in two different species (mouse and horse). The modulation of this common cellular actor could be a preventive therapeutical strategy regarding the occurrence of secondary cognitive disorders. The two models we used have a certain scientific and technical advantage in (i) the demonstration of a modulation pathway involving microglia (mutant murine model), and (ii) the evaluation of the drug effectiveness before the setting up of clinical trials in humans (spontaneous equine pathology)

    The right to human projection : the institutional conditions and the anthropological and ecological virtues

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    L’autonomie projective peut ĂȘtre garantie par la « qualification pour les projets », qui accorde de maniĂšre universelle aux sujets une reconnaissance Ă  la fois sociale et monĂ©taire de leur puissance de projection. Une telle autonomie demeure une coquille vide si les sujets ne parviennent pas Ă  rĂ©aliser concrĂštement des projets. Nous pouvons, en cas d’échec, recourir au « droit opposable au projet » afin que la puissance publique planifie un projet en fonction de notre qualification et des besoins anthropologiques et Ă©cologiques identifiĂ©s par une communautĂ© politique. Si nous sommes certains de pouvoir participer effectivement Ă  des projets, le ferons-nous toujours dans de bonnes conditions ? Pour le garantir, est nĂ©cessaire une structure juridique qui reconnaĂźt et rĂšgle les rapports de subordination et de dĂ©pendance qui sont Ă  l’Ɠuvre au sein des projets. Penser l’autonomie projective, c’est penser une « communautĂ© projective » Ă  mĂȘme de constituer un cadre commun et durable des projets. GrĂące aux « communs des projets », l’accĂšs aux ressources indispensables Ă  la rĂ©alisation d’un projet est ouvert et rĂ©glĂ©, pour que nul d’entre nous ne puisse priver tous les autres de leur droit effectif Ă  la projection. De telles ressources proviennent de la Terre, travaillĂ©e par la main humaine, et de la technique, c’est Ă  dire de l’ensemble des savoirs, des savoir faire et des instruments inventĂ©s et transmis au cours de l’histoire. Si tous les projets se rĂ©alisent en mĂȘme temps, ne risquent-ils pas de s’entraver mutuellement, voire de s’entredĂ©truire ? Une « planification commune des projets » a pour objectif d’harmoniser les projets dans le temps et dans l’espace, en fonction de principes Ă©cologiques et anthropologiques.Projective autonomy can be guaranteed by “qualifications for projects", which universally grants individuals both social and monetary recognition of their projection power. Such autonomy remains an empty shell if individuals fail to complete specific projects. In the event of failure, we may resort to the “opposable right to the project" so the public power may plan a project according to our qualifications and the anthropological and ecological needs identified by a political community. If we are certain that we can actually participate in projects, will we always do so under proper conditions? In order to guarantee this, a legal structure is needed that recognizes and regulates the relationships of subordination and dependency at work within the projects.Thinking about projective autonomy means thinking of a "projective community" that may constitute a common and sustainable framework for projects. Thanks to "project commons", access to the resources essential to the implementation of a project is open and regulated so no one may deprive anyone else of their effective right to projection. Such resources come from the Earth, worked by the human hand, and from technology; in other words, from all the knowledge, know-how and tools invented and transmitted throughout history. If all projects are carried out at the same time, is there not a risk they will create mutual obstacles or destroy each other? “Common project planning" aims to harmonize projects in time and space, according to ecological and anthropological principles
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