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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.
61

Análise morfológica e imunohistoquímica de placentas caninas provenientes de eutocia e distocia / Morphological and immunohistochemical analysis of canine placentas from eutocia and dystocia

Costa, Isadora Frazon [UNESP] 07 August 2015 (has links) (PDF)
Made available in DSpace on 2016-07-01T13:10:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-08-07. Added 1 bitstream(s) on 2016-07-01T13:14:10Z : No. of bitstreams: 1 000866897.pdf: 2241837 bytes, checksum: 4f7edd4ceb0f7cb049f481298ec4b4c5 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A placentação e o desenvolvimento das membranas fetais na espécie canina atualmente são estudados de forma extensiva, já que o conhecimento da morfologia da placenta possibilita reconhecer corretamente alterações patológicas e sua possível correlação com a viabilidade neonatal. O presente estudo tem como objetivo a caracterização morfológica e imunohistoquímica de placentas de cadelas provenientes de eutocia e distocia. Para o desenvolvimento deste experimento foram coletadas 80 placentas, de acordo com o tipo de parto as placentas foram divididas em três grupos experimentais, GN (n=40) placentas obtidas de parto normal, GC (n=28) placentas obtidas de cesariana e GAUP (n=12) placentas obtidas de cadelas em atonia uterina primária. Fragmentos 1cm x 1cm foram seccionados da região próxima ao cordão umbilical e armazenados em formol tamponado 10% durante 48 horas, a seguir, foram transferidos para álcool 70%, no qual permaneceram até o processamento para o estudo histopatológico e imunohistoquímico. Foram reconhecidas áreas de hemorragia, necrose, inflamação e calcificação nas placentas dos três grupos estudados. A hemorragia no parênquima placentário foi identificada em todos os grupos experimentais, não apresentando diferença significativa. A necrose evidenciada junto a face materna foi uma constante nos grupos avaliados, entretanto foram observados na região lamelar focos e áreas de necrose no GC e GAUP, porém estes achados não foram estatisticamente relevantes quanto a comparação ao GN. A inflamação foi raramente observada no GN, esteve pouco presente no GC e predominou nas amostras placentárias do GAUP. Os focos de calcificação identificados foram mais notórios no GC e GAUP. Nos grupos estudados foram observadas alterações discretas quanto a integridade histológica dos hematomas marginais. Nas placentas GN a imunomarcação para vimentina mostrou-se intensa e homogênea em toda zona lamelar, fato... / Placentation and the development of fetal membranes in dogs are currently studied extensively, since the knowledge of morphology of the placenta enables properly recognize pathological changes and its correlation with neonatal viability. We aimed to characterize morphologically and immunohistochemically placentas of bitches from eutocia and dystocia. For that 80 placentas were collected and classified according to the type of delivery into three experimental groups,GN (n = 40) placentas obtained from normal delivery, GC (n = 28) placentas obtained from cesarean section and GAUP (n = 12) placentas obtained from bitches with uterine atony. 1cm x 1cm pieces were cut from the region near the umbilical cord and stored in 10% buffered formalin for 48 hours following, were transferred to 70% alcohol, which remained until processing for histopathological and immunohistochemical study. In this research, areas of hemorrhage, necrosis, inflammation and calcification were observed in the placentas in all three groups. Hemorrhagic areas were identified in the placental parenchyma in all groups, without significant difference. The evident necrosis in the placenta maternal face was constant in the groups, we observe areas and spots of necrosis in the lamellar region in GC and GAUP, but those findings were not statistically significant when compared to GN. Inflammation was rarely observed in the GN and it was observed in a few samples in the GC, however it was predominant in samples from GAUP. Calcification spots were observed in GC and GAUP. In the studied groups, discrete alterations were observed when histological integrity of marginal hematomas was evaluated. In GN the immunostaining for vimentin proved to be intense and homogeneous throughout lamellar zone, however this was not observed in GC and GAUP, which presented immunostaining characterized by variation of intensity. For cytokeratin there was no difference between experimental groups. The RP...
62

A distonia focal na embocadura dos instrumentistas do naipe de metais: um estudo de caso

Oliveira, Ester 07 August 2014 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-05-25T12:02:13Z No. of bitstreams: 2 Dissertação - Ester Oliveira - 2014.pdf: 511456 bytes, checksum: f80dc4397cb0f5aa84be8543b3144fba (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-05-25T12:06:29Z (GMT) No. of bitstreams: 2 Dissertação - Ester Oliveira - 2014.pdf: 511456 bytes, checksum: f80dc4397cb0f5aa84be8543b3144fba (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-05-25T12:06:29Z (GMT). No. of bitstreams: 2 Dissertação - Ester Oliveira - 2014.pdf: 511456 bytes, checksum: f80dc4397cb0f5aa84be8543b3144fba (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-08-07 / This work is the final product of the course Master of Music in Music Performance and subarea is divided into two parts: Part A: Artistic Production, with two recitals, one of Defense and other, called Recital I, relating to compliance mandatory prerequisite of the course; and PART B: Scientific Article, consists of a text resulting from the formal research that presents a case study of focal dystonia. The paper discusses the levels of stress and anxiety in four subjects with historical and focal dystonia. The methodology used was a brief literature review and the application of questionnaires and (musician habits and the K-MPAI inventory. - Kenny Music Performance Anxiety Inventory) in four subjects who self-reported diagnosed with Focal Dystonia Carry out a survey of habits current that may have been stimuli that led these professionals to develop the said disorder. It is concluded that there is still no full understanding of this disorder and there is little information on the matter between the parties concerned higher, affected musicians, which probably contributes to the great worsening of existing cases. However, it was possible to expand through this, references in English on the subject and propose reflections on a more critical and conscious musical practice. / O presente trabalho é o produto final do curso de Mestrado em Música na subárea Performance Musical e está dividido em duas partes: PARTE A: Produção Artística, composta por dois recitais, sendo um de Defesa e outro, chamado Recital I, referente a cumprimento de pré-requisito obrigatório do curso; e PARTE B: Artigo Científico, composta por um texto resultante da pesquisa formal que apresenta um estudo de caso sobre distonia focal. O texto discute os níveis de estresse e ansiedade em quatro sujeitos com histórico e distonia focal. A metodologia utilizada foi uma breve revisão da literatura e a aplicação de e questionários (hábitos do músico e o inventário K-MPAI – Kenny Music Performance Anxiety Inventory, em quatro sujeitos que se autodeclararam diagnosticados com Distonia Focal. Faz-se um levantamento dos hábitos atuais que possam ter sido estímulos que levaram tais profissionais a desenvolver o referido distúrbio. Conclui-se que ainda não há total compreensão deste distúrbio e há pouca informação sobre o assunto entre os maiores interessados, os músicos afetados, o que provavelmente contribui para o grande agravamento dos casos existentes. Contudo, foi possível ampliar, através deste, as referências em língua portuguesa sobre o assunto e propor reflexões sobre uma prática musical mais crítica e consciente.
63

Individual Response to Botulinum Toxin Therapy in Movement Disorders: A Time Series Analysis Approach

Leplow, Bernd, Pohl, Johannes, Wöllner, Julia, Weise, David 27 October 2023 (has links)
On a group level, satisfaction with botulinum neurotoxin (BoNT) treatment in neurological indications is high. However, it is well known that a relevant amount of patients may not respond as expected. The aim of this study is to evaluate the BoNT treatment outcome on an individual level using a statistical single-case analysis as an adjunct to traditional group statistics. The course of the daily perceived severity of symptoms across a BoNT cycle was analyzed in 20 cervical dystonia (CD) and 15 hemifacial spasm (HFS) patients. A parametric single-case autoregressive integrated moving average (ARIMA) time series analysis was used to detect individual responsiveness to BoNT treatment. Overall, both CD and HFS patients significantly responded to BoNT treatment with a gradual worsening of symptom intensities towards BoNT reinjection. However, only 8/20 CD patients (40%) and 5/15 HFS patients (33.3%) displayed the expected U-shaped curve of BoNT efficacy across a single treatment cycle. CD (but not HFS) patients who followed the expected outcome course had longer BoNT injection intervals, showed a better match to objective symptom assessments, and were characterized by a stronger certainty to control their somatic symptoms (i.e., internal medical locus of control). In addition to standard evaluation procedures, patients should be identified who do not follow the mean course-of-treatment effect. Thus, the ARIMA single-case time series analysis seems to be an appropriate addition to clinical treatment studies in order to detect individual courses of subjective symptom intensities.
64

Correlation Between Weight Loss and Select Motor Scores From a Chart Review of Huntington's Disease Patients

Yoder, Jennifer M. 25 June 2012 (has links)
No description available.
65

Sensomotorische Phänotypisierung von Mausmodellen für zentralnervöse Bewegungsstörungen

Gerstenberger, Julia 29 May 2017 (has links) (PDF)
Einleitung: Tiermodelle spielen für die Aufklärung pathophysiologischer Mechanismen und die Entwicklung erfolgsversprechender Therapieoptionen zentralnervöser Bewegungsstörungen eine unverzichtbare Rolle. Die Identifizierung von Gendefekten für die Parkinson-Krankheit und Dystonien ermöglichte die Generierung von Tiermodellen mit einer hohen „construct validity“. Weibliche transgene Thy1-aSyn Mäuse sowie DYT1 Knock-in (KI) Mäuse zeigen jedoch keine motorischen Störungen. In der vorliegenden Arbeit sollten zur Aufdeckung sensomotorischer Beeinträchtigungen, die bei Parkinson- und Dystoniepatienten beobachtet werden, detaillierte Untersuchungen des Verhaltens an diesen beiden Mausmodellen durchgeführt werden. Zielstellung: Zunächst sollte ein sensitiver Verhaltenstest konstruiert und entwickelt werden, bei dem sich ändernde sensorische Stimuli während der Ausübung der motorischen Aufgabe impliziert werden. Bei der Etablierung dieses sogenannten „adaptiven rotierenden Balkentests“ (ARB-Test) sollte auch der Einfluss des genetischen Hintergrunds bei Wildtyp-Mäusen evaluiert werden. Daraufhin sollte überprüft werden, ob dieser Test den Endophänotyp der weiblichen Thy1-aSyn Mäuse aufdecken kann. In dem DYT1 KI Mausmodell sollte der Frage nachgegangen werden, ob die Tiere Verhaltensdefizite in spezifischen Tests zeigen, die sensomotorische Verschaltungen untersuchen. Material und Methoden: Die mRNA-Expression von α-Synuclein in der Substantia nigra bei männlichen und weiblichen Thy1-aSyn Mäusen wurde mithilfe der quantitativen Echtzeit-PCR (qPCR) ermittelt. Im Anschluss an die Entwicklung des neuen Verhaltensapparates für den ARB-Test wurden Thy1-aSyn Tiere beider Geschlechter in diesem Versuch getestet und ihre Leistung den Ergebnissen auf etablierten motorischen Verhaltenstests („challenging beam test“, „pole test“) gegenübergestellt. Um den Einfluss des Hintergrundstammes auf das Verhalten der Tiere auf dem ARB-Test zu untersuchen, wurden Wildtypen der reinen C57BL/6J-Linie sowie Hybrid-Tiere des Stammes C57Bl/6J × DBA2 (BDF1) allen drei o. g. Versuchen unterzogen. Bei den Mäusen des DYT1 KI Modells wurde der „adhesive removal test“ und der ARB-Test zur Analyse der Sensomotorik durchgeführt. Im Vergleich dazu wurden vielfältige Verhaltensparameter in einer Reihe vorwiegend motorischer (Offenfeld-Test, „challenging beam test“, „pole test“, Zylinder-Test, Block-Test, Nestbau-Test) und kognitiver („y-maze test“) Verhaltenstests ausgewertet. Ergebnisse: Bei den weiblichen Thy1-aSyn Mäusen wurde eine geringere Expression des Transgens im Vergleich zu den männlichen Tieren festgestellt. Der neue ARB-Test wurde erfolgreich etabliert und konnte signifikante Verhaltensdefizite der weiblichen und männlichen Mutanten des Parkinson-Modells im Vergleich zu den Kontrolltieren aufdecken. Der genetische Hintergrund beeinflusste die Leistung der Wildtypen auf diesem Balkentest. Während die DYT1 KI Tiere in den rein motorischen und kognitiven Versuchen keine Beeinträchtigungen des Verhaltens zeigten, konnten der „adhesive removal test“ sowie der neue ARB-Test signifikante sensomotorische Defizite der KI Mäuse im Unterschied zu den Wildtypen zum Vorschein bringen. Schlussfolgerung: Im Thy1-aSyn Mausmodell konnte die Bedeutung der sensomotorischen Integration für die Ausprägung motorischer Defizite sowie für eine mögliche Kompensation solcher motorischen Beeinträchtigungen demonstriert werden. Hierfür hat sich der neu entwickelte, sensitive ARB-Test als geeignet herausgestellt. Die Aufdeckung von Beeinträchtigungen der Sensomotorik spricht auch bei den DYT1 KI Tieren für den Einfluss einer gestörten sensomotorischen Integration bei der Ausprägung der Symptomatik. Damit eignet sich dieses Mausmodell für die Untersuchung weiterer Parameter, die Auswirkungen auf die Aufdeckung des Phänotyps und die Penetranz der Erkrankung haben sowie um die zugrunde liegenden pathophysiologischen Mechanismen zu erforschen.
66

Characterization of the Zona Incerta

Green, Heather Joyce 01 January 2005 (has links)
Parkinson's Disease affects more than 1 million people in the United States with 60,000 new cases being diagnosed each year. Currently, there is no cure for Parkinson's Disease, but there are several treatment options available. Currently the most popular surgical option is Deep Brain Stimulation. Microelectrode recording helps identify nuclei as the microelectrode passes through them. While the firing frequencies of the target nuclei are well defined, other nuclei are not. This study will attempt to characterize the Zona Incerta, which is the structure directly above the Subthalamic Nucleus, a target nucleus. Characterization of the firing frequency of the Zona Incerta will help aid Deep Brain Stimulation procedures. Looking at the Interspike Intervals for 25 files showed that the average firing frequency is 11.6Hz. A file recorded in the STN was used for comparison and to validate the methods used. This yielded an average firing frequency of 37.5Hz.
67

Distonia focal e a atividade do instrumentista de sopro / Focal dystonia and activity instrumentalist of wind

GARCIA, Ricardo Rosembergue 31 March 2012 (has links)
Made available in DSpace on 2014-07-29T16:25:13Z (GMT). No. of bitstreams: 1 ARTIGO FINAL - Ricardo Rosembergue.pdf: 1546157 bytes, checksum: 1e6c96e6efa16325f1f9490114d77c2c (MD5) Previous issue date: 2012-03-31 / This paper discusses the musician's dystonia and its relationship to performance on wind instruments. The work presents from the literature review on the subject the concept of dystonia, as well as the musician's focal dystonia of its main causes and symptoms related to instrumental practice and lists possible ways of prevention based on the aspects of preparation and holding of musical performance and situations related to the theme. The survey data were obtained through consultation with professional musicians in the city of Goiania. The results revealed several meanings of musical practice and overuse, health problems related to performance anxiety and musical performance and still making music that can overcome the physical and mental limits of the performer. Due to the incidence of psychophysical problems in musicians, undertook a discussion about the possibility of developing disorders in brass and it was concluded that the musical performance can generate states of illness and development of disorders such as focal dystonia of the musician. It was recommended a few precautions to be taken as preventive measures for occupational illness. / O presente trabalho discute a distonia focal do músico e sua relação com a performance em instrumentos de sopro. O trabalho apresenta a partir da revisão de literatura sobre o tema o conceito de distonia, bem como o de distonia focal do músico suas principais causas e sintomas relacionados com a prática instrumental e elenca possíveis caminhos de prevenção com base nos aspectos de preparação e realização da performance musical e situações relacionadas ao tema. Os dados da pesquisa foram obtidos por meio de consultas a músicos profissionais na cidade de Goiânia. Os resultados obtidos revelaram diversas significações sobre prática musical e sobreuso, problemas de saúde relacionados à performance musical e ansiedade na performance e ainda que o fazer musical pode ultrapassar os limites físicos e mentais do performer. Devido à incidência de problemas psicofísicos em músicos, empreendeu-se uma discussão sobre a possibilidade de desenvolvimento de distúrbios em instrumentistas de sopro e concluiu-se que a performance musical pode gerar estados de adoecimento e desenvolvimento de distúrbios como a distonia focal do músico. Recomendou-se alguns cuidados a serem tomados como medidas preventivas de adoecimento ocupacional.
68

Komplementäre Therapie der zervikalen Dystonie

Viehmann, Manuel Alexander 14 June 2013 (has links) (PDF)
In der Behandlung der zervikalen Dystonie wird die Therapie mit Botulinumtoxin (BTX) erfolgreich angewendet. Neben dieser Therapie werden von Patienten oft alternative Therapien (CAM [Complementary and Alternative Medicine]) angesprochen und ausprobiert. Diese Studie geht der Frage nach, wie häufig CAM-Therapien genutzt werden, wie deren Wirkung bewertet wird und ob es Prädiktoren für die Therapiewahl gibt. Zur Datenerhebung wurden 265 Fragebögen von zwei Patientengruppen ausgewertet. Gruppe 1 (n=101) bestand aus Patienten der Botulinumtoxinsprechstunde des Universitätsklinikums Leipzig und der Paracelsus Klinik Zwickau. Gruppe 2 (n=165) wurde aus Mitgliedern des Selbsthilfeverbandes Bundesverband-Torticollis e.V. rekrutiert. Bei 86% der Patienten wurde die Therapie mit BTX angewendet. Von den Therapiemöglichkeiten der CAM wurden am häufigsten physikalische Therapien (Massagen n=171) genannt. Am besten bewertet wurden jedoch, neben der BTX-Therapie, spezielle physiotherapeutische sowie psychotherapeutische Verfahren. Die CAM-Therapien wurden häufig in Kombination mit der BTX-Therapie angewendet und von Patienten, deren Erkrankung einen langen chronischen Verlauf vorwies (>10 Jahre). Als Prädiktoren für die Wahl einer CAM-Therapie zeigten sich eine Zugehörigkeit zur Gruppe 2, aufgetretene Nebenwirkungen im Rahmen der BTX-Therapie, männliches Geschlecht und erhöhter Stress bei den Erkrankten. Außerdem fand sich ein signifikanter Unterschied zu einem höheren Bildungsabschnitt und Arbeit in gehobeneren Berufsgruppen bei Patienten, die vermehrt CAM Therapie anwenden. Zusammenfassend wurden CAM-Therapien, neben der Behandlung mit BTX, häufig von den Befragten angewendet. Hohe Zufriedenheitswerte erzielte eine Kombination mit physiotherapeutischen Verfahren oder Psychotherapie. Die Wahl von CAM-Therapien ist von der Erkrankungsdauer, Bildungslage und finanziellen Ressourcen abhängig.
69

Μελέτη των νευροδιαβιβαστικών συστημάτων της ντοπαμίνης και του γλουταμινικού οξέος στο κεντρικό νευρικό σύστημα πειραματικών μοντέλων μυών και επίμυων

Γιαννακοπούλου, Δήμητρα 20 April 2011 (has links)
Στην παρούσα διατριβή μελετήθηκε το ντοπαμινεργικό και γλουταμινεργικό σύστημα των βασικών γαγγλίων, χρησιμοποιώντας δύο διαφορετικά μοντέλα ζώων. Ο πρώτος στόχος ήταν να εξεταστεί εάν η μεταφορά του γονιδίου TrkA σε νευρώνες της μέλαινας ουσίας (SN) ενήλικων επίμυων επιδρά στις νευροχημικές τους ιδιότητες, απουσία ή παρουσία εξωγενούς νευροαυξητικού παράγοντα (NGF) στο ραβδωτό σώμα. Η εκτοπική έκφραση του TrkA στην SN οδήγησε σε σημαντική μείωση του mRNA της υδροξυλάσης της τυροσίνης (TH), της TH ανοσοδραστικότητας και του mRNA του DAT στη δεξιά SN σε σύγκριση με την ετερόπλευρη, ενώ δεν βρέθηκε καμία διαφορά στο mRNA των υποδοχέων ντοπαμίνης D2 και της ειδικής δέσμευσης του [3Η]raclopride στην SN. Δεν παρατηρήθηκαν μεταβολές στις θέσεις δέσμευσης του [3Η]WIN35428 και της ανοσοδραστικότητας του DAT στο ομόπλευρο ραβδωτό σώμα, καθώς και στις θέσεις δέσμευσης των μετασυναπτικών υποδοχέων ντοπαμίνης D1 και D2, όπως καθορίζεται από τους ιχνηθέτες [3H]SCH23390 και [3Η] raclopride, αντίστοιχα. Επιπλέον, δεν βρέθηκαν σημαντικές μεταβολές στους υποδοχείς NMDA και AMPA. Τα αποτελέσματα αυτά δείχνουν ότι η εκτοπική έκφραση του TrkA στην SN ρυθμίζει αρνητικά την ΤΗ και οδηγεί σε ανεξάρτητες από τον NGF αποκρίσεις. O δεύτερος στόχος της διατριβής ήταν η μελέτη του ντοπαμινεργικού συστήματος σε ένα μοντέλο DYT1 δυστονίας μυός. Σε διαγονιδιακούς μυς με υπερκινητική και μη υπερκινητική συμπεριφορά παρατηρήθηκε μείωση των υποδοχέων ντοπαμίνης D2 στο ραβδωτό σώμα, όπως προσδιορίστηκε από τη δέσμευση του [3H]raclopride, και τoυ mRNA των D2 στην SNpc, σε σχέση με μη διαγονιδιακούς μυς. Δεν παρατηρήθηκε διαφορά στη δέσμευση του [3H]SCH23390 ή του [3H]WIN35428 στο ραβδωτό σώμα διαγονιδιακών μυών. Τα δεδομένα προτείνουν μία πιθανή εμπλοκή της ντοπαμινεργικής νευροδιαβίβασης στην παθοφυσιολογία της DY1 δυστονίας. / In the present thesis we examined the dopaminergic and glutamatergic neurotransmission systems of basal ganglia, using two different animal models. The first goal was to investigate whether TrkA gene transfer into substantia nigra (SN) neurons of adult rats influence some of their neurochemical properties, in the absence or presence of exogenous nerve growth factor (NGF) delivery in the striatum. Ectopic expression of TrkA in SN resulted in a significant decrease of tyrosine hydroxylase (TH) immunoreactivity, TH mRNA and DAT mRNA expression in the right SN compared to the contralateral side, while no difference was found in the mRNA expression of D2 DA receptors and [3H]raclopride binding in SN. No significant changes were seen in the density of DAT by measuring [3H]WIN35428 binding sites and DAT immunoreactivity in the ipsilateral striatum, as well as in the number of postsynaptic striatal D1 and D2 receptor binding sites, as determined by [3H]SCH23390 and [3H]raclopride, respectively. Furthermore, no significant changes were found in NMDA and AMPA receptors. These data suggest that ectopic TrkA expression in SN downregulates TH in nigral dopaminergic neurons and elicits NGF-independent responses. The second goal of the present thesis was to examine the dopaminergic system of basal ganglia in a mouse model of DYT1 dystonia. A decrease in striatal D2 binding sites, measured by [3H]raclopride binding, and D2 mRNA expression in substantia nigra pars compacta (SNpc) was revealed in affected and unaffected transgenic mice when compared with non-transgenic. No difference in D1 receptor binding and DAT binding, measured by [3H]SCH23390 and [3H]WIN35428 binding, respectively, was found in striatum of transgenic animals. These data suggest a possible involvement of dopamine neurotransmission in the pathophysiology of DYT1 dystonia.
70

Evaluation des réseaux neuronaux vecteurs de comportements par imagerie anatomique et fonctionnelle in vivo chez l'homme / In vivo evaluation of human neural circuits underlying behavior by anatomic and functional neuroimage studies

Gonzalez Martinez, Maria Victoria 28 March 2014 (has links)
L'évolution des connaissances dans le domaine de la neurochirurgie fonctionnelle, la neuroradiologie et les études de traçage neuronal par virus neurotropes ont permis d'étudier les circuits sous-tendant l'expression clinique de plusieurs syndromes neurologiques. La stimulation cérébrale profonde (SCP) du globus pallidus interne (GPi) est une thérapie validée dans les syndromes dystono-dyskinétiques (SDD) isolés. L'extension des indications vers des SDD secondaires ou hérédo-dégénératifs nous confronte à la nécessité d'améliorer notre compréhension des mécanismes de réorganisation fonctionnelle du circuit moteur et de l'intégrité résiduelle des connexions anatomiques. L'efficacité de la SCP dans les SDD complexes est déterminée par la préservation relative de la voie pyramidale, les interactions du circuit cortico-striato-pallido-thalamique et cérébello-thalamo-cortical et la réorganisation du réseau moteur au niveau cortical. Ce travail de thèse a essayé d’évaluer différentes composantes du réseau moteur in vivo chez l’homme à travers de l’étude de trois pathologies du mouvement associées à un SDD complexe. L’application de la SCP à la maladie de Huntington (MH) est un modèle d'étude du réseau moteur dans le contexte d’un SDD associé à une dégénérescence des neurones striato-pallidaux. Nous avons fait une étude prospective pour évaluer l'efficacité à long terme de la SCP du GPi sur les symptômes moteurs de la MH. Sept patients ayant une chorée sévère réfractaire au traitement pharmacologique ont été inclus dans l'étude. Nous avons observé une réduction significative de la chorée chez tous les patients avec un effet maintenu dans le temps (suivi médian de 3 ans). La bradykinésie et la dystonie ont montré une tendance (non significative) à une aggravation progressive. L'analyse anatomo-fonctionnelle du réseau moteur résiduel sous-tendant un SDD secondaire (dû à une lésion cérébrale acquise) a été abordée par deux techniques de neuroimagerie avancée. La réorganisation du circuit moteur dans le cadre d’une hémidystonie a été évaluée par IRM fonctionnelle. Les objectifs principaux ont été: 1) l’évaluation des régions activées par l'exécution d’une tâche motrice chez un groupe de patients hémidystoniques par rapport à un groupe de sujets témoins; 2) l’identification des profils d'activation selon le phénotype clinique (hypo/hyperkinétique) ou radiologique (lésion localisée en amont ou en aval du GPi) (des critères qui orientent l’éligibilité pour la SCP pallidale). Les études individuelles des patients ont montré des profils d'activation hétérogènes avec une activation bilatérale possible malgré le caractère unilatéral des lésions. En comparaison avec les sujets témoins, les patients ont présenté une réduction de l'activation au niveau thalamique, pallidal et temporal médial du côté ipsilatéral à la lésion. Les patients atteints d'une hémidystonie hypokinétique ont montré un profil d'activation bi-hémisphérique, désorganisé, ce qui pourrait expliquer le manque de réponse à la SCP observée dans cette présentation clinique. L'imagerie du tenseur de diffusion (DTI) a été appliquée à l'étude de la distribution topographique et la gravité des lésions de la substance blanche d'un groupe de patients atteints d'un SDD secondaire à une encéphalopathie anoxique néonatale par rapport à un groupe témoin. L'étude TBSS (tract based spatial statistics) a identifié la présence d'anomalies diffuses de la microstructure de la substance blanche (diminution de la fraction d’anisotropie (FA)) chez les patients. La technique de tractographie probabiliste a été utilisée pour reconstruire les faisceaux corticospinaux (CS) et thalamocorticaux (TC) (les voies efférentes du circuit moteur) et pour obtenir des paramètres quantitatifs DTI moyens pour chaque faisceau. La FA moyenne des faisceaux TC est diminuée chez les patients. Nous avons étudié la corrélation entre les paramètres cliniques et neurophysiologiques et les paramètres DTI du groupe de patients. / Advances in the field of functional neurosurgery, neuroradiology and virus neuronal tracing studies have enabled to deepen our knowledge of the circuits underlying the clinical expression of several neurologic syndromes. Globus pallidus internus (GPi) deep brain stimulation (DBS) is a validated technique for the treatment of isolated (primary) dystonia-dyskinesia syndromes (DDS). Broadening indications for DBS therapy to complex DDS (secondary and heredodegenerative disorders) require further understanding of motor circuit functional reorganization mechanisms and residual anatomic connections integrity. The efficacy of neuromodulation in these complex dystonia syndromes is determined by the relative preservation of pyramidal pathway, the interactions between cortico-striato-pallido-thalamic and cerebello-thalamo-cortical circuits and motor network reorganization at the cortical level. This thesis has tried to evaluate the different components of human motor network in vivo through the study of three different movement disorders associated with complex dystonia. The application of DBS to Huntington’s disease (HD) is a model for the study of the motor network in the context of this heredodegenerative DDS associated with striatal neuron degeneration in the cortico-striato-pallido-thalamic loop. We have conducted a prospective study to evaluate long-term motor outcome of GPi DBS in HD. Seven patients with severe chorea refractory to medical treatment were included in the study. Significant and sustained reduction of chorea was observed for all patients until last follow-up visit (median follow-up was 3 years). Bradykinesia and dystonia showed a non-significant trend towards progressive worsening. Anatomic and functional assessment of the motor circuit following brain injury (secondary DDS) has been approached by two different advanced neuroimaging techniques. We have studied motor circuit reorganization underlying hemidystonia in functional magnetic resonance imaging (fMRI). The main objectives of this study were: 1) to evaluate activation regions associated with motor task execution in a group of hemidystonic patients compared with another group of healthy control subjects; 2) to identify activation patterns related to clinical (hypo or hyperkinetic) or radiological (prepallidal or postpallidal) phenotypes (following clinical criteria relevant for DBS therapy eligibility). Activation patterns associated with motor-task execution were heterogeneous in single-subject studies. Despite the unilateral distribution of lesions leading to dystonia, bilateral activation was found in several subjects. Compared with healthy control group, hemidystonic patients showed reduced brain activation in ipsilesional thalamus, globus pallidus and medial temporal areas. Hypokinetic hemidystonic subgroup showed widespread bilateral overactivity involving both hemispheres. Poor clinical outcome associated with this clinical presentation could be explained by DBS therapy inability to modulate a highly disorganized network. Diffusion tensor imaging (DTI) has been applied to the study of the topographic distribution and severity of white matter lesions in a group of patients with a DDS secondary to neonatal anoxic encephalopathy in comparison with a healthy control group. TBSS (tract based spatial statistics) found widespread areas of abnormal white matter microstructure (decreased fractional anisotropy (FA)) in the corpus callosum, corona radiata and posterior limb of the internal capsule in the group of patients. After running probabilistic tractography to reconstruct corticospinal and thalamocortical tracts (motor circuit output pathways), mean quantitative tract-derived DTI parameters were calculated for each single tract. This study found decreased mean FA in thalamocortical tracts in the group of patients as compared to healthy controls. Clinical scores and neurophysiological measures were also analyzed and correlated with DTI parameters.

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