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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Vers une imagerie fonctionnelle de l'electrophysiologie corticale modelisation markovienne pour l'estimation des sources de la magneto/electroencephalographie et evaluations experimentales .

Baillet, Sylvain 08 July 1998 (has links) (PDF)
La magnetoencephalographie (meg) et l'electroencephalographie (eeg) possèdent une resolution temporelle exceptionnelle qui les destine naturellement a l'observation et au suivi des processus electrophysiologiques sous-jacents. Cependant, il n'existe pas a ce jour de méthode d'exploitation des signaux meg et eeg qui puisse les faire prétendre au statut de veritables méthodes d'imageries. En effet, la modélisation de la production des champs magnétiques et des différences de potentiels électriques recueillis sur le champ necessite a priori la prise en compte de la géométrie complexe de la tete et des proprietes de conductivite des tissus. Enfin, l'estimation des générateurs est un probleme qui fondamentalement ne possede pas de solution unique. La motivation initiale de notre travail a concerne le developpement d'approches permettant d'obtenir une tomographie corticale de l'electrophysiologie. Nous avons alors mis en uvre une modelisation markovienne du champ d'intensite des sources en proposant des modeles spatio-temporels adaptes a la meeg, et notamment aux variations morphologiques locales des structures anatomiques corticales. De plus, nous avons exploite cette notion d'ajustement local afin de proposer une nouvelle méthode de fusion de données meg et eeg au sein d'un seul et unique problème inverse. Nous avons également accorde une importance particulière a l'évaluation des méthodes proposées. Ainsi, et pour aller au-dela des simulations numériques souvent trop limitatives, nous avons mis au point un fantôme physique adapte a la meg et a l'eeg qui nous a permis d'etudier les performances des estimateurs en association avec des modeles de tete a divers degres de realisme. Enfin, nous proposons une première application a ces méthodes dans le cadre de l'identification de réseaux épileptiques chez les patients souffrant d'épilepsie partielle.
142

Impact du genre et du modèle sur les mécanismes d’épileptogénèse dans le cerveau immature

Foadjo Awoume, Berline 04 1900 (has links)
Les modèles kainate et pentylènetétrazole représentent deux modèles d’épilepsie du lobe temporal dont les conséquences à long terme sont différentes. Le premier est un modèle classique d’épileptogénèse avec crises récurrentes spontanées tandis que le second se limite aux crises aigües. Nous avons d’abord caractérisé les différents changements survenant dans les circuits excitateurs et inhibiteurs de l’hippocampe adulte de rats ayant subi des crises à l’âge immature. Ensuite, ayant observé dans le modèle fébrile une différence du pronostic lié au genre, nous avons voulu savoir si cette différence était aussi présente dans des modèles utilisant des neurotoxines. L’étude électrophysiologique a démontré que les rats KA et PTZ, mâles comme femelles, présentaient une hyperactivité des récepteurs NMDA au niveau des cellules pyramidales du CA1, CA3 et DG. Les modifications anatomiques sous-tendant cette hyperexcitabilité ont été étudiées et les résultats ont montré une perte sélective des interneurones GABAergiques contenant la parvalbumine dans les couches O/A du CA1 des mâles KA et PTZ. Chez les femelles, seul le DG était légèrement affecté pour les PTZ tandis que les KA présentaient, en plus du DG, des pertes importantes au niveau de la couche O/A. Les évaluations cognitives ont démontré que seuls les rats PTZ accusaient un déficit spatial puisque les rats KA présentaient un apprentissage comparable aux rats normaux. Cependant, encore une fois, cette différence n’était présente que chez les mâles. Ainsi, nos résultats confirment qu’il y a des différences liées au genre dans les conséquences des convulsions lorsqu’elles surviennent chez l’animal immature. / Kainate and pentylenetetrazole models represent two animal models of temporal lobe epilepsy in which long-term consequences differ. The first model is a classical model of epileptogenesis with spontaneous recurrent seizures while the second one is limited to acute seizures. We wanted to characterize the difference in changes which occur in excitatory and inhibitory systems of the hippocampus of adult males and females having suffered an episode of status epilepticus during the immature stage of life. Besides having noticed a difference between genders in the febrile model, our second objective was to see if this difference was also present in models using neurotoxins. Electrophysiology recordings indicated that KA and PTZ rats (both male and female) showed a hyperactivity of NMDA receptors in CA1, CA3 and DG pyramidal cells. Anatomical modifications causing hyperactivity were studied and results show a selective loss of specific GABA interneurons PV in the O/A layer of CA1 region of the hippocampus in KA and PTZ male rats. However in female rats, only the DG layer was slightly affected in PTZ while female KA presented losses in both DG and O/A layers. Cognitive evaluation indicated that only PTZ rats showed a spatial impairment since KA rats had a similar learning pattern as controls. However, once again, that difference was observed only in males and not in females. In summary, our results confirmed that there is a difference between genders regarding brain damages after having suffered an episode of status epilepticus during the immature stage.
143

A longitudinal analysis of the prescribing patterns of anti–epileptic medicine by using a medicine claims database / T. van Zyl

Van Zyl, Tiaan January 2010 (has links)
The prevalence of epilepsy in society is general knowledge; however the impact on social activity as well as other daily factors are not always fully recognised. Epilepsy frequently poses a problem with regard to work–related activities (Heaney, 1999:44). Moran et al. (2004:425) indicated that the major impacts of epilepsy on life were work and school difficulties, driving prohibition, psychological and social life of which restriction of work or schooling has the greatest impact on epileptic’s life. In all cases the type, severity, and frequency of the seizures as well as the age would be relevant. Davis et al. (2008:451) established that 39% of all epileptics were not adherent to their therapy and in patients over 65 this was even higher at 43 %. Non–adherence with antiepileptic medicine appears to be related to increased health care utilisation and costs and may also lead to an increased probable accidents or injuries The general objective was to investigate anti–epileptic medicine prescribing patterns and treatment cost in a section of the private health care sector by using a medicine claims database. A retrospective drug utilisation study was done on the data claims from a pharmacy benefit management company for the study period 1 January 2005 to 31 December 2008. Firstly epilepsy was investigated in order to understand the disease and to determine the prevalence and treatment thereof. It was found that epilepsy is still one of the most common neurological conditions and according to the findings, 2 out of every hundred patients were using anti–epileptic medicine in this section of the private health care sector. To make this condition socially more acceptable and understandable, public education for special target groups concerning the disorder must be conducted as well as employment training programmes for people with epilepsy themselves. The utilisation patterns of anti–epileptic drugs were reviewed, analysed and interpreted. It was determined that anti–epileptic medicine items are relatively expensive with regards to other medicine items on the total database. With regard to gender, more females are using anti–epileptic medicine than males on the database. The largest age group of patients using anti–epileptic medicine, is between > 40 years and <= 64 years of age. It was also clear that prevalence increase as age increase. With regard to the different prescribers, the number of items prescribed by a general practitioner was almost double that of the other prescribers. It was further established that newer anti–epileptic medicines are more expensive than older anti–epileptic medicine according to the cost per tablet in this section of the private health care sector. Carbamazepine and valproate were the two active ingredients that were most frequently prescribed as a single item on a prescription. After a cost–minimisation analysis was done, R134 685.66 could have been saved when generic substitution was implemented. The refill–adherence rate decreased as age increased. Only 30.46% of the trade names was refilled according to acceptable refill–adherence rates. The refill–adherence rate according to active ingredient showed that medicine items containing, phenobarbitone/vit B or gabapentin had the lowest unacceptable refill–adherence rate. The limitations for this study was stipulated and recommendations for further research regarding anti–epileptic medicine were also made. / Thesis (M.Pharm (Pharmacy Practice))--North-West University, Potchefstroom Campus, 2011.
144

A longitudinal analysis of the prescribing patterns of anti–epileptic medicine by using a medicine claims database / T. van Zyl

Van Zyl, Tiaan January 2010 (has links)
The prevalence of epilepsy in society is general knowledge; however the impact on social activity as well as other daily factors are not always fully recognised. Epilepsy frequently poses a problem with regard to work–related activities (Heaney, 1999:44). Moran et al. (2004:425) indicated that the major impacts of epilepsy on life were work and school difficulties, driving prohibition, psychological and social life of which restriction of work or schooling has the greatest impact on epileptic’s life. In all cases the type, severity, and frequency of the seizures as well as the age would be relevant. Davis et al. (2008:451) established that 39% of all epileptics were not adherent to their therapy and in patients over 65 this was even higher at 43 %. Non–adherence with antiepileptic medicine appears to be related to increased health care utilisation and costs and may also lead to an increased probable accidents or injuries The general objective was to investigate anti–epileptic medicine prescribing patterns and treatment cost in a section of the private health care sector by using a medicine claims database. A retrospective drug utilisation study was done on the data claims from a pharmacy benefit management company for the study period 1 January 2005 to 31 December 2008. Firstly epilepsy was investigated in order to understand the disease and to determine the prevalence and treatment thereof. It was found that epilepsy is still one of the most common neurological conditions and according to the findings, 2 out of every hundred patients were using anti–epileptic medicine in this section of the private health care sector. To make this condition socially more acceptable and understandable, public education for special target groups concerning the disorder must be conducted as well as employment training programmes for people with epilepsy themselves. The utilisation patterns of anti–epileptic drugs were reviewed, analysed and interpreted. It was determined that anti–epileptic medicine items are relatively expensive with regards to other medicine items on the total database. With regard to gender, more females are using anti–epileptic medicine than males on the database. The largest age group of patients using anti–epileptic medicine, is between > 40 years and <= 64 years of age. It was also clear that prevalence increase as age increase. With regard to the different prescribers, the number of items prescribed by a general practitioner was almost double that of the other prescribers. It was further established that newer anti–epileptic medicines are more expensive than older anti–epileptic medicine according to the cost per tablet in this section of the private health care sector. Carbamazepine and valproate were the two active ingredients that were most frequently prescribed as a single item on a prescription. After a cost–minimisation analysis was done, R134 685.66 could have been saved when generic substitution was implemented. The refill–adherence rate decreased as age increased. Only 30.46% of the trade names was refilled according to acceptable refill–adherence rates. The refill–adherence rate according to active ingredient showed that medicine items containing, phenobarbitone/vit B or gabapentin had the lowest unacceptable refill–adherence rate. The limitations for this study was stipulated and recommendations for further research regarding anti–epileptic medicine were also made. / Thesis (M.Pharm (Pharmacy Practice))--North-West University, Potchefstroom Campus, 2011.
145

Large-scale modeling of epileptic seizures dynamics

Proix, Timothée 30 October 2015 (has links)
Les crises épileptiques sont des épisodes paroxysmiques d'activité cérébrale hypersynchrone. Ce travail de thèse s'attache à examiner les mécanismes de propagation des crises d'épilepsie sur une échelle temporelle lente et une grande échelle spatiale dans le cerveau humain et à les appliquer au contexte clinique. Chez les patients souffrant d'épilepsie partielle réfractaire, les crises débutent dans certaines régions localisées du cerveau, dénommées zone épileptogène, avant de recruter des régions distantes. Le succès de l'ablation chirurgicale de la zone epileptogène dépend principalement de sa délimitation adéquate, un problème souvent épineux en pratique clinique. À cela s'ajoute notre compréhension parcellaire des mécanismes à l'origine des crises et de leur propagation. Nous utilisons un modèle mathématique de masse neuronale reproduisant le décours temporel de l'activité moyenne critique et intercritique d'une région cérébrale, guidé de manière autonome par une variable permittive lente. Nous introduisons tout d'abord un couplage permittif lent entre ces masses neuronales, afin de révéler l'importance de la variété lente dans le recrutement des régions cérébrales dans la crise. Nous présentons ensuite un pipeline de traitement des données structurelles et de diffusion IRM pour reconstruire automatiquement le cerveau virtuel d'un patient. Nous utilisons ensuite une analyse de stabilité linéaire et la connectivité large-échelle pour prédire la zone de propagation. Nous appliquons notre méthode à un jeu de données de 15 patients épileptiques et démontrons l'importance du connectome pour prédire la direction de propagation des crises. / Epileptic seizures are paroxysmal hypersynchronizations of brain activity, spanning several temporal and spatial scales. In the present thesis, we investigate the mechanisms of epileptic seizure propagation on a slow temporal and large spatial scale in the human brain and apply them to a clinical context. For patients with partial refractory epilepsy, seizures arise from a localized region of the brain, the so-called epileptogenic zone, before recruiting distant regions. Success of the resective surgery of the epileptogenic zone depends on its correct delineation, which is often difficult in clinical practice. Furthermore, the mechanisms of seizure onset and recruitment are still largely unknown. We use a mathematical neural mass model to reproduce the time course of interictal and ictal mean activity of a brain region, in which the switching between these states is guided by an autonomous slow permittivity variable. We first introduce a slow permittivity coupling function between these neural masses, hypothesizing the importance of the slow manifold in the recruitment of brain regions into the seizure. Before exploring large-scale networks of such coupled systems, we present a processing pipeline for automatic reconstruction of a patient's virtual brain, including surface and connectivity (i.e., connectome), using structural and diffusion MRI, and tractography methods. Using linear stability analysis and large-scale connectivity, we predict the propagation zone. We apply our method to a dataset of 15 epileptic patients and establish the importance of the connectome in determining large-scale propagation of epileptic seizures.
146

Caractérisation métabolomique des tissus épilectogènes par spectroscopie RMN à haute résolution à l'angle magique (RMN HRMAS) : applications à l'épilepsie temporale humaine et animale / Metabolomic profile of cerebral biopsies in temporal lobe epilepsy (TLE) using High Resolution Nuclear Magnetic Resonance Spectroscopy at Magic Angle Spinning (HRMAS NMR) : applications to human and animal model of TLE.

Detour, Julien 02 October 2013 (has links)
La métabolomique a pour objet l’identification et la quantification de métabolites dans un échantillon biologique. Cette discipline s’inscrit dans une approche du vivant connue sous le terme de « biologie des systèmes ». La spectroscopie par résonance magnétique nucléaire haute résolution à l’angle magique (RMN HRMAS) est une méthode de choix pour l’obtention de ce type de profilage métabolique. L’épilepsie du lobe temporal (ELT) est une épilepsie focale fréquente associée le plus souvent à des pertes neuronales sélectives, une gliose réactionnelle et une plasticité cellulaire spécifique. Bien que restant débattue, une origine neurométabolique reste un axe de recherche majeur. A ce jour une caractérisation métabolomique des tissus épileptogènes par RMN HRMAS reste à effectuer. Notre travail a consisté dans un premier temps à caractériser, chez le rat, les effets des méthodes de prélèvement et de fixation sur le métabolome cérébral dans le cadre des acquisitions RMN HRMAS. Dans un second temps, nous avons travaillé sur le modèle animal lithium-pilocarpine d’ELT. Nous avons pu décrire le métabolome issu des données RMN 1H HRMAS de différentes structures cérébrales impliquéesdans l’épileptogénèse. Des analyses multivariées de type PLS-DA ont pu mettre en évidence des profils métaboliques pathologiques au sein du cortex entorhinal et de l’hippocampe. A l’aide de substrats marqués au carbone 13 ([1-13C]glucose et de [1,2-13C]acétate) nous avons étudié les voies métaboliques neuronales et gliales. Nos résultats suggèrent l’absence d’anomalies métaboliques au sein des astrocytes. Enfin dans un dernier temps, nous avons effectué des analyses RMN 1H HRMAS sur près de 200 échantillons cérébraux de patients atteints d’ELT. Une analyse multivariée a permis de distinguer les profils métaboliques des hippocampes sclérosés et non sclérosés. En revanche la construction de modèles sur la base d’hypothèses clinico métaboliques (durée de la maladie, fréquence de crises, antécédents de convulsions fébriles) n’a pas permis d’identifier de profils métaboliques spécifiques. L’ensemble de ces données suggère l’existence de profils métabolomiques distincts en fonction des caractéristiques neuropathologiques des patients atteints d’ELT. Notre travail confirme la nécessité d’une approche intégrée de type « biologie des systèmes » pour l’étude de l’ELT aussi bien chez l’homme que dans des modèles animaux. / Metabolomics relates to the identification and quantification of metabolites in biological samples. This discipline is part of an approach known under the term of "systems biology". High Resolution Nuclear Magnetic Resonance Spectroscopy at Magic Angle Spinning (HRMAS NMR) is a method for obtaining metabolic profiling in such sample. Temporal Lobe Epilepsy (TLE ) is a common focal epilepsy often associated with selective neuronal loss, reactive gliosis and specific cellular plasticity. A neurometabolic origin of this epilepsy is a major area of research. To date no characterization of human cerebral biopsy from TLE patients has been conducted using HRMAS NMR. In the present work we aimed first at characterizing, in rats, the effects of sampling methods and fixation on brain metabolome under HRMAS NMR acquisitions. In a second step, we studied the lithium-pilocarpine model of TLE. In this model, we could describe the metabolome from HRMAS 1H NMR data of different brain structures involved in epileptogenesis. Multivariate analysis could highlight pathological metabolic profiles in the entorhinal cortex and hippocampus. Using substrates labeled with carbon 13 ( [1 -13C ]-glucose and [1,2-13C ]-acetate) we studied neuronal and glial metabolic pathways. Our results suggest the absence of metabolic abnormalities in astrocytes metabolism as previously reported. Finally, we conducted HRMAS 1H NMR analysis in nearly 200 brain samples from TLEpatients. Multivariate analysis was able to distinguish metabolic profiles between sclerotic and non sclerotic hippocampi. However mutlivariate models based on clinico- metabolic assumptions (disease duration, frequency of seizures, history of febrile seizures ) did not identify specific metabolic profile. All these data suggest the existence of distinct metabolomic profile based on neuropathological features of patients with TLE. Our work confirm the need of an integrated approach such as " systems biology" for the study of TLE in humans as long as in animal models.
147

Learning and memory consolidation processes in children and adults: a neurophysiological and neuropsychological investigation

Urbain, Charline 30 May 2012 (has links)
Learning and memory consolidation processes in children and adults: a<p>neurophysiological and neuropsychological investigation.<p><p>Sleep is a complex and active state of the brain, associated with essential functional changes<p>[1]. Accumulated evidence in the adult population indicates that sleep participates in the<p>consolidation of declarative (i.e. memory for facts and episodes) and procedural (i.e. skills<p>and habits) memory, allowing novel information to be integrated for the long term in cerebral<p>networks [2]. Whether sleep supports memory consolidation in children likewise and to the<p>same extent than in adults remains disputed. In this framework, I have developed<p>experiments aimed at investigating sleep-dependent consolidation processes both in children<p>and adults, using behavioral and neurophysiological techniques (magneto-encephalography<p>[MEG]; electro-encephalography [EEG]; functional magnetic resonance imaging [fMRI]). To<p>sum up, researches conducted during my PhD thesis have contributed to start unraveling<p>neurophysiological mechanisms participating in sleep-dependent consolidation processes.<p>On the one hand, I report that despite a lack of detectable behavioral differences, posttraining<p>sleep plays a role in reshaping the cerebral networks subtending implicit motor<p>sequence learning in adults [3]. I also showed using a motor adaptation task [4] that sleep<p>contributes to the consolidation of procedural memory in children [5]. On the other hand, I<p>have evidenced neuromagnetic correlates of learning novel semantic representations in<p>children [6-7], and is currently finalizing the analysis of the effect of a post-training nap on the<p>consolidation of these representations. Finally, I showed in epileptic children that interictal<p>epileptic discharges (IED) during sleep impairs declarative memory consolidation processes<p>[8-9], and that this phenomenon is reversible upon pharmacological treatment suppressing<p>IED. Altogether, these findings advocate the need to explore further memory consolidation<p>and its neurophysiological basis in children, both healthy and suffering from various brain<p>pathologies [10].<p>[1] Urbain C. Peigneux, P. & Schmitz R. Sleep and the Brain. (to appear). In The Oxford Handbook of<p>Sleep and Sleep Disorders. C. M. Morin and C. A. Espie (Eds.). Oxford University Press, Oxford, NY.<p>[2] Peigneux P. Schmitz R. & Urbain C. Sleep and Forgetting. In Forgetting. S. Della Sala (Ed.).<p>Psychology Press, Hove, UK. 2010. (pp. 165-184).<p>[3] Urbain C. Schmitz R. Schmidt C. Cleeremans A. Van Bogaert P. Maquet P. and Peigneux P.<p>(submitted). Neuroanatomical Sleep-Dependent Processing in the Probabilistic Serial Reaction Time<p>Task.<p>[4] Huber, R. Ghilardi, M.F. Massimini, M. And Tononi, G. Local sleep and learning. Nature, 2004,<p>430, 78-84.<p>[5] Urbain C. Houyoux E. Albouy G. Peigneux P. (in preparation). Sleep-dependent consolidation of<p>procedural learning in children.<p>[6] Urbain C. Schmitz R. Op De Beeck M. Bourguignon M. Galer S. X. De Tiège, Van Bogaert P.<p>and Peigneux P. (in preparation). How learning new meanings about novel objects modulates cerebral<p>activity in children: A MEG Study.<p>[7] Urbain C. Schmitz R. Bourguignon M. Op De Beeck M. Galer S, De Tiège X. Van Bogaert P.<p>Peigneux P. (2011). Learning and Fast-Mapping Meanings to Novel Object in Children: A MEG Study.<p>17th Annual Meeting of the Organization for Human Brain Mapping [HBM], 26-30 June 2011, Québec<p>City, Canada<p>[8] Urbain C. et al. Is sleep-related consolidation impaired in focal idiopathic epilepsies of childhood?<p>A pilot study, Epilepsy and Behavior, 2011, 22(2), 380-384.<p>[9] Van Bogaert P. Urbain C. Galer S. Ligot N. Peigneux P. and De Tiège X. Impact of focal<p>interictal epileptiform discharges on behaviour and cognition in children. Neurophysiologie<p>Clinique/Clinical Neurophysiology, 2012, 42(1–2), 53-58. / Doctorat en Sciences Psychologiques et de l'éducation / info:eu-repo/semantics/nonPublished
148

Connectivité fonctionnelle interictale dans les épilepsies du lobe temporal : étude par SEEG et IRMf au repos / Interictal fonctionnal connectivity in temporal lobe epilepsies : an SEEG and resting-state fMRI study

Bettus, Gaëlle 22 January 2010 (has links)
Le but de ce travail de thèse a été de caractériser in vivo chez l’Homme, la connectivité cérébrale sur son versant fonctionnel, par le biais de deux techniques: la stéréoélectroencéphalographie (SEEG) et l’IRM fonctionnelle (IRMf) de repos. Ces travaux se sont intégrés dans le cadre du bilan préchirurgical des épilepsies du lobe temporal pharmacorésistantes, dont le but est de déterminer la zone épileptogène à réséquer pour traiter ces patients. Alors que plusieurs études en électrophysiologie ont montré que durant les crises, il existait une synchronisation anormalement élevée entre les structures impliquées dans les processus épileptogènes, aucune donnée de connectivité n’était disponible en période intercritique. Pourtant, la période intercritique est le siège d’anomalies interictales enregistrées en EEG, de profonds remaniements morphologiques, et est associée à des troubles cognitifs. Nous apportons avec ce travail, grâce au recueil et au traitement de signaux SEEG et IRMf enregistrés durant la période intercritique, de nouvelles connaissances i) sur l’organisation de la connectivité fonctionnelle basale (CFB) chez les sujets sains ; ii) sur les altérations de la CFB chez des groupes de patients mais également au niveau individuel ; iii) sur le rapport entre ces anomalies de CFB et les troubles cognitifs observés chez ces patients ; iv) enfin, sur les différences et les similitudes de la CFB évaluée par SEEG et IRMf chez les mêmes sujets, ouvrant ainsi de nouvelles perspectives dans la compréhension des relations entre le signal BOLD et le signal EEG. / The aim of this thesis was to characterize the Human brain functional connectivity in vivo based on signals recorded using stereoelectroencephalography (SEEG) and resting-state functional MRI (fMRI). This work was conducted during the presurgical assessment of drug resistant temporal lobe epilepsy, which aims at determining the epileptogenic zone to be removed to treat these patients. While several electrophysiological studies have shown high synchronization between structures involved in the epileptogenic process during seizure, no similar connectivity data was available during inter-critical period. However, the interictal period is characterized by spikes recorded on EEG, morphological alterations and cognitive impairment. By analyzing fMRI and SEEG signals recorded during the interictal period, this work provides new insights into, i) basal functional connectivity (BFC) organization in healthy subjects, ii) BFC alterations in patients groups but also at the individual level, iii) the relationship between these BFC abnormalities and cognitive impairment observed in these patients; iv) the differences and similarities of BFC evaluated by SEEG and fMRI in the same subjects, thus opening up new perspectives in better understanding of relationships between BOLD and SEEG signal coupling.
149

Vyšetření genů DNM2, GARS, MORC2, TRPV4 a SOD1 u českých pacientů s dědičnou neuropatií axonálního typu / Examination of the genes DNM2, GARS, MORC2, TRPV4 and SOD1 among Czech patients with hereditary neuropathy axonal type

Neupauerová, Jana January 2019 (has links)
Examination of the genes DNM2, GARS, MORC2, TRPV4 and SOD1 among Czech patients with hereditary neuropathy axonal type For my PhD thesis I chose to work with patients with axonal form of CMT, because at that time axonal forms were less likely to be clarified by classical methods of molecular genetics. For further examination in patients with unclear cause of the axonal CMT, the genes DNM2, GARS and TRPV4 were selected. The aim was to determine the significance of pathogenic mutations in these genes as the cause of CMT2 in Czech patients. In the course, we identified causal variants in the genes MORC2 and SOD1 with WES. Therefore, we have tested additional CMT2 patients for the presence of these variants. Using Sanger sequencing, I examined a representative set of patients for the DNM2 (37), GARS (10) and TRPV4 (24) genes without finding a causal mutation, then we investigated genes SOD1 (43 patients) and MORC2 (161 patients). The cohort (50 patients) was also subjected to MLPA analysis using a P406-A1 CMT2 duplication and deletion detection kit for genes RAB7A, GARS, HSPB1, HSBP8 and SPTLC1 (kit P406-A1 CMT2). At that time, massively parallel sequencing (MPS) was becoming important. We compared the cost of classical sequencing versus MPS, and accordingly, we decided that the genes DNM2, GARS, MORC2, TRPV4...
150

Strukturální podklady kognitivního deficitu v zobrazování magnetické rezonance. / Structural Patterns of Cognitive Deficits in MR Imaging.

Buksakowska, Irena January 2019 (has links)
Structural and diffusion imaging patterns that can be evaluated using MRI in patients with cognitive deficits are the central theme of the proposed work. First, the clinical and neuroimaging background of dementias has been reviewed in a broader context, with a special focus on Alzheimer's disease (AD) and differential diagnoses. The second part of this thesis contains four consecutive experimental studies. The primary objective of the first two studies was to obtain structural and microstructural information on the neurodegenerative processes characteristic for AD on global and regional levels. For this purpose, several complementary approaches were used and the focus was shifted from grey to white matter (GM/WM). The following two studies focused on the differential context of WM microstructural alterations in normal pressure hydrocephalus (NPH) and distinctive patterns of WM disintegrity in temporal lobe epilepsy (TLE). The most important conclusion of our studies is that structural and diffusion imaging proved to be useful in identifying regionally specific and disproportionate loss of brain volume and microstructure in several pathological processes underlying cognitive deterioration. The use of distinctive morphometric methods yielded complementary information on AD-related atrophy patterns,...

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