Gotowa bibliografia na temat „IRM 23Na”

<p><strong>Background and Objective:</strong> Dengue fever (DF) has been a major health concern globally. Pakistan is also combating this infection for the last decade. Cytokine genes play an important role in DF pathogenesis. This study aimed to analyze dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) and tumor necrosis factor &alpha; (TNF-&alpha;) genes promoter polymorphisms in DF patients.</p> <p><strong>Methods:</strong> A total of 140 (n = 140) dDF patients were recruited for study at the Department of Human Genetics and Molecular Biology of University of Health Sciences, Lahore, Pakistan over a period of 3 years. Simple DF was noted in 105 patients (75%) while 35 (25%) showed bleeding complications. All patients were found positive for dengue non-structural protein or dengue IgM. All patients were tested for two polymorphisms in TNF-&alpha; (-238G/A, and -308G/A) and one polymorphism in DC-SIGN (-336G/A) using restriction fragment length polymorphism technique. A single nucleotide polymorphism stats program was used for statistical analysis.</p> <p><strong>Results:</strong> Susceptibility to develop dengue infection in the presence of -336G allele odds ratio (OR = 27.95, p = &lt;0.0001) and GG genotype (OR = 183.77, p = &lt;0.0001) was found to be significantly associated in this study. Presence of a combination of alleles -336G/-238A/-308A was noted in 59.4% of DF cases and 7.6% healthy controls, a difference with statistical significance (OR = 31.46, p = &lt;0.0001). Moreover, prevalence of DF symptoms showed a trend higher in G-carriers versus non-G-carriers of DC-SIGN -336 polymorphism.</p> <p><strong>Conclusion:</strong> This work suggests a potential association of DC-SIGN -336 polymorphism with susceptibility to develop symptomatic dengue illness. However, no potential association was found between TNF-&alpha; promoter polymorphisms and dengue infection in this study.</p>

AbstractSodium‐containing chalcogenide materials are emerging as a class of solid electrolytes for application in inexpensive all‐solid‐state sodium‐ion batteries due to their high ionic conductivity, abundance, and degree of synthetic and structural variability. Members of the solid solution Na3PS4−xSex, which are promising solid electrolytes for sodium‐ion batteries, are prepared by reaction at high temperature. With increasing substitution of S by Se, the structure transforms from tetragonal (space group P21c for x = 0, 1) to cubic (space group I3m for x = 2, 3, 4). Within the solid solution, the S and Se atoms are completely disordered in the environments around the P atoms, in accordance with a binomial distribution, as inferred by the 31P nuclear magnetic resonance (NMR) spectra. In 23Na NMR experiments conducted at different magnetic fields and temperatures, quadrupolar lineshapes are observed that are influenced by sodium ion dynamics; the activation energies decrease from 0.21 to 0.15 eV on progressing from the S‐ to the Se‐rich members. A dynamic model is proposed to account for the changes in the 23Na quadrupolar lineshapes by switching the orientations of the electric field gradient and chemical shift anisotropy tensors when Na+ ions hop to the four nearest Na sites.

Background and purposeImpaired sensorimotor function, reduced physical activity and unemployment are common challenges in persons with multiple sclerosis (pwMS), even when disability is low. CoreDISTparticipation is a new, multidisciplinary intervention delivered across healthcare levels systematically addressing these elements. This study primarily aimed to evaluate the feasibility of CoreDISTparticipation in terms of process, resources, management, and scientific outcomes. The secondary aim was to evaluate initial efficacy in terms of possible short-term effects compared with the usual care on barriers to employment, balance, walking, health-related quality of life (HRQoL), and physical activity.MethodsThis assessor-blinded prospective pilot randomized controlled trial included 29 pwMS [Expanded Disability Status Scale (EDSS): 0–3.5] randomly allocated to the intervention group (CoreDISTparticipation) (n = 15) or usual care (n = 14). CoreDISTparticipation consists of three phases: (1) hospital outpatient clinic: MS nurse work-focused session and physiotherapist exploring balance; (2) municipality: a digital meeting with pwMS, employer, MS nurse, and physiotherapist addressing employment and physical activity, 4 weeks indoor CoreDIST balance training (60 min × 2/week); and (3) 4 weeks outdoor CoreDIST balance training and high-intensity running/walking (60 min × 2/week). Assessments were undertaken at baseline and at weeks 6 and 11. Primary feasibility metric outcomes were the reporting of process, resources, management, and scientific outcomes. Efficacy measures included evaluation of the Multiple Sclerosis Work Difficulties Questionnaire-23 Norwegian Version (MSWDQ-23NV) and 6 Minute Walk-test as well as the Trunk Impairment Scale-modified Norwegian Version, Mini-Balance Evaluation Systems Test (Mini-BESTest), Multiple Sclerosis Walking Scale-12, Multiple Sclerosis Impact Scale-29 Norwegian Version (MSIS-29NV), ActiGraph wGT3x-BT monitors, and AccuGait Optimized force platform. The statistical analyses included repeated-measures mixed models performed in IBM SPSS Version 29.ResultsThe primary feasibility metric outcomes demonstrated the need for minor adjustments in regard to the content of the intervention and increasing the number of staff. In regard to the efficacy measures, one person attended no postintervention assessments and was excluded, leaving 28 participants (mean EDSS: 1.8, SD: 1). The mean percentage employment was 46.3 (SD: 35.6) and 65.4 (SD: 39.3) in the CoreDISTparticipation and usual care group, respectively. No between-group differences were found. MSWDQ-23NV demonstrated a within-group difference of 5.7 points from baseline to Week 11 (P = 0.004; confidence interval: 2.2–9.3). Mini-BESTest and MSIS-29NV demonstrated within-group differences. The study is registered in ClinicalTrials.gov (Identifier: NCT05057338).DiscussionThe CoreDISTparticipation intervention is feasible to support pwMS when the identified feasibility metric outcomes in regard to process, resource, management, and scientific outcome metrics are adjusted to improve feasibility. Regarding efficacy measures, no between-group differences were detected; however, within-group differences in barriers to employment, balance, and HRQoL were detected for the CoreDISTparticipation group. A larger comparative trial is needed to explore between-group differences and should accurately and precisely define usual care and address the identified limitations of this study.

Le concept de réseaux - l'idée que deux ou plusieurs nœuds distribués peuvent interagir pour produire un phénomène - a longtemps été utilisé dans la recherche et le traitement de l'épilepsie. En effet, même dans les épilepsies considérées comme «focales», les perspectives cliniques et théoriques soulignent l'importance des questions suivantes, à savoir : 1) comment pouvons-nous localiser, partitionner et caractériser les réseaux impliqués dans l'épilepsie et 2) dans quelle mesure ces réseaux interagissent avec le réseau cérébral à grande échelle? Récemment, la notion de réseaux pathologiques dans l'épilepsie a été renforcée par l’apport de la neuroimagerie, avec en particulier le paradigme 'd'état de repos' qui reconnaît l'information inhérente à l'activité spontanée du cerveau, en plus de celle liée aux événements transitoires exogènes et paroxystiques endogènes.En tirant partie de ces techniques, ce travail fournit de nouveaux concepts sur 1) les relations multimodales et le couplage entre l’hémodynamique et la connectivité fonctionnelle électro physiologique aussi bien dans les cortex épileptiques que non affectés, 2) les processus pathologiques affectant l’homéostasie ionique et les dysfonctionnements neuronaux dans les réseaux épileptiques, 3) les interactions au niveau de groupe entre les réseaux épileptiques et les propriétés topologiques du cerveau, et 4) comment les interactions entre la pathologie épileptique et des propriétés uniques du réseau cérébral peuvent contribuer à produire des effets cliniques au niveau du réseau
The concept of networks – the idea that two or more distributed nodes may interact to produce a phenomenon – has long been of utility in research into and the treatment of epilepsy. Indeed, even in epilepsies deemed ‘focal’, clinical and theoretical insights underline the importance of the questions 1) how can we localize, partition and characterize networks involved in epilepsy, and 2) to what extent do such networks interact with the brain network at large? Recently, the notion of pathological network effects in epilepsy has been reinvigorated with input from neuroimaging, especially a ‘resting-state’ paradigm that recognizes the systemic information inherent in the ongoing activity of the brain in addition to that provided when it is disturbed by transient exogenous events and endogenous paroxysms. By leveraging these techniques, this work provides novel insights into 1) the multimodal relationships and coupling between haemodynamic- and electrophysiologically-defined functional connectivity, both in epileptic and unaffected cortices 2) pathological processes affecting ionic homeostasis and neural dysfunction in epileptic networks 3) group-level interactions between epileptic networks and brain network topological properties and 4) how interactions between epileptic pathology and unique brain network properties may contribute to produce to clinical effects at the network level. This work opens up new perspectives on the understanding of network effects in epilepsy, sources of variance in their analysis, the biological processes occurring in parallel and contributing to them and their role in an individualized understanding of pathology

La spectroscopie par résonance magnétique permet de manière non invasive, de caractériser et suivre l'évolution du métabolisme cérébral in vivo chez l’Homme. Néanmoins, de nombreux biais empêchent l’obtention d’une caractérisation métabolique cérébrale complète, un prérequis essentiel pour mieux comprendre une pathologie diffuse comme la Sclérose en Plaques (SEP).Mon premier projet a donc consisté à transposer une technique de spectroscopie rapide en 3 dimensions, acquise dans deux orientations spatiales. Cette comparaison a mis en évidence des diminutions de métabolites reliés à la viabilité et à l’activité neuronale, dans des régions fonctionnelles motrices et cognitives, mais également une activité gliale accrue dans les lésions de substance blanche mais aussi en dehors. La deuxième étude a visée à caractériser d'un point de vue métabolique, les accumulations cérébrales de sodium observées chez les patients atteints de SEP par IRM du 23Na. Nous avons pu mettre en évidence des corrélations significatives entre les accumulations de sodium et les diminutions de NAA mettant en lumière un lien fort entre ces accumulations et les phénomènes de souffrance neuronale.Enfin, le dernier projet a eu pour but d'améliorer la résolution spatiale de l'imagerie spectroscopique du proton en tirant partie des avantages d'un imageur clinique 7 Tesla. Après avoir corrigé différents problèmes comme les inhomogénéités B0 et B1 ainsi que l’artefact de déplacement chimique, nous avons obtenu le profil du NAA, de la Choline et de la Créatine pour 4 gros noyaux thalamiques. De plus, l’analyse statistique a mis en évidence des différences métabolique entre les noyaux Thalamiques
Magnetic Resonance Spectroscopy (MRS) allows to characterize, in vivo and non-invasively, the cerebral metabolism in Human. Nevertheless, use MRS in clinical routine is marginal and it is impossible to obtain whole brain metabolic topography, mandatory step in order to understand diffuse pathology like Multiple Sclerosis (MS).First of all, we aimed to transpose a fast 3D-MRSI sequence acquired in two different orientations. We observed significant decrease in metabolites linked with neuronal health and activity, in important motor and cognitive areas, and also increase in glial activation, inside white matter T2 lesions but also outside in normal appearing white and grey matter.Secondly, we aimed to characterize the metabolic counterpart of cerebral sodium accumulations observed, using 23Na MRI, in MS patients. We observed significant correlations between sodium accumulations and decrease in NAA highlighting a strong link between sodium accumulations and neuronal suffering.Finally, we attempted to improve spatial resolution of proton MR spectroscopy using 7 Tesla scanner. We also addressed ultra-high field artifacts like B0 and B1 inhomogeneities as well as chemical shift displacement error. We obtained metabolic profiles of NAA, Choline and Creatine for 4 big thalamic nuclei. Moreover, statistical analysis evidencing metabolic differences between nuclei in same hemisphere but also for some nuclei left/right differences

Une consommation excessive de sel (NaCl) augmente considérablement le risque de maladies cardiovasculaires. Cependant, la consommation moyenne reste jusqu’à deux fois supérieure à la recommandation de l'OMS, qui est de 5 g par jour. La réduction de la consommation de sel est donc une priorité absolue pour prévenir les maladies non transmissibles telles que les maladies cardiovasculaires. Jusqu'à présent, l'industrie a déjà réussi à réduire les teneurs en sel de nombreux aliments commerciaux, mais la nécessité de poursuivre la réduction de la consommation de sel reste pressante. L'une des principales préoccupations est que les consommateurs augmentent leur consommation de Sel Discrétionnaire (SD) pour compenser la perte de goût, ce qui rendrait la reformulation des aliments moins efficace. Jusqu'à présent, l'utilisation du sel discrétionnaire a reçu peu d'attention et n'est pas clairement ciblée par les recommandations, bien qu'elle contribue significativement à la consommation globale de sel.Objectifs :Ce projet de thèse s'inscrit dans ce contexte ; il fait partie du projet global et multidisciplinaire Sal&Mieux (fondé par l'Agence Nationale de la Recherche), qui vise à identifier des leviers sur la façon d'optimiser l'utilisation du SD. Deux objectifs principaux ont été définis pour cette thèse : (i) mieux comprendre comment le SD interagit avec les matrices alimentaires, puis comment celui-ci est libérée dans la bouche en fonction de différentes pratiques d’assaisonnement ; (ii) identifier les conséquences en termes de goût salé et de la saveur ; le défi étant d'identifier les pratiques domestiques qui permettent d’optimiser un maximum l'utilisation du SD. L'hypothèse de base est que, selon le type d'aliment et les pratiques de salage, le SD interagit différemment avec la matrice alimentaire et est libéré dans la bouche selon divers schémas dynamiques qui déterminent la perception globale du goût salé.Méthodologie :Le travail de thèse était basé sur des approches expérimentales complémentaires suivant une voie transdisciplinaire. Premièrement, la Résonance Magnétique Nucléaire 23Na (RMN) et l'Imagerie Magnétique Nucléaire (IRM) ont été utilisées pour évaluer quantitativement l'interaction et la distribution du sodium pour une variété de matrices alimentaires (carottes, pâtes et poulet) et de pratiques de salage (moment de l'ajout de sel, forme des cristaux de sel, influence de l'ajout d'arôme). Deuxièmement, une évaluation sensorielle a été réalisée pour mettre en évidence les pratiques domestiques susceptibles d'améliorer la perception sensorielle du SD. En outre, la libération temporelle du sodium des produits alimentaires a également été contrôlée in vitro à l'aide d'un simulateur de bouche dédié.Résultats :Ce travail a permis de démontrer pour la première fois que la consommation discrétionnaire de sel pouvait être réduite grâce à certaines pratiques domestiques d'assaisonnement et ce pour une large gamme d'aliments réels. Nous avons observé que le salage après la cuisson, conduisait à une plus forte intensité salée par rapport au salage au début du processus de cuisson. Cette plus forte intensité du goût salé a été particulièrement observée lors de l'utilisation de sels commerciaux (sel de mer fin et fleur de sel). Nous avons démontré sur la matrice carotte que cette augmentation du goût salé était due à une distribution hétérogène du sel dans la matrice alimentaire lors du salage après cuisson. Cette distribution inhomogène induit une libération de sel très variable pendant la mastication, créant des pulse de sel qui sont connues pour renforcer le goût salé. Nous avons également démontré que l'utilisation d'arômes, dont certains disponibles au supermarché, pouvait renforcer l'intensité du goût salé d’aliments domestiques.En fin de compte, ces pratiques de salage peuvent contribuer de manière significative aux initiatives mondiales visant à réduire la consommation de sel
Excessive salt (NaCl) intake is known to increase dramatically the risk of cardiovascular diseases (CVDs). However, the average consumption is still twice the WHO recommendation of 5 g per day. Reducing salt intake is therefore a top priority to prevent non-communicable diseases such as CVDs. Thus far, the industry has already successfully lowered salt levels in many commercial foods but the need to pursue the reduction of salt intake remains pressing. A major concern is that consumers increase their use of discretionary salt (DS) to compensate for the loss of taste, which would make food reformulation less effective. The use of DS has received little attention so far and it is not clearly targeted by recommendations even though it contributes to salt intake.Objectives:This thesis project is anchored within this context; it is part of the global and multidisciplinary project Sal&Mieux (founded by the French ANR), which aims at identifying levers to be transferred in operational guidelines on how to optimize DS use. Two main objectives were defined for this PhD: (i) better understand how DS interacts with food matrices, then how it is released in the mouth depending on various seasoning practices; (ii) identify the consequences in terms of salty taste and flavor perception; the challenge being to identify the best domestic practices to optimize DS use. The core hypothesis is that, according to the type of food and the salting practices, DS interacts with the food matrix differently and is released in the mouth following various dynamic patterns that drive overall salty taste perception.Methodology:The thesis work was based on complementary experimental approaches following a transdisciplinary path. First, 23Na Nuclear Magnetic Resonance (NMR) and Magnetic Nuclear Imaging (MRI) were used to quantitatively evaluate the interaction and distribution of sodium for a variety of food matrices (carrots, pasta, and chicken) and salting practices (moment of salt addition, shape of salt crystals, influence of flavour addition). Second, sensory evaluation was performed to underline domestic practices that can increase sensory perception of DS. In addition, the temporal release of sodium from food products was also monitored in vitro using a dedicated mouth simulator.Results:This work demonstrated for the first time that discretionary salt consumption could be reduced by certain domestic seasoning practices, for a wide range of real foods. We observed that salting after cooking led to a higher saltiness intensity than salting at the beginning of the cooking process. This higher intensity of salty taste was particularly observed when using commercial salts (fine sea salt and fleur de sel). We demonstrated on the carrot matrix that this increase in salty taste was due to a heterogeneous distribution of salt in the food matrix during salting after cooking. This inhomogeneous distribution induces a highly variable release of salt during chewing, creating salt pulses that are known to enhance salty taste. We have also demonstrated that the use of flavourings, some of which are available in supermarkets, can reinforce the intensity of the salty taste of domestic foods.Ultimately, these salting practices can make a significant contribution to global initiatives to reduce salt consumption