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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.
341

Исследование антиоксидантных свойств препаратов сочетанного действия : магистерская диссертация / Study of antioxidant properties of combined action

Борисова, М. В., Borisova, M. V. January 2021 (has links)
Целью выпускной квалификационной работы является комплексное исследование интегральных антиоксидантных параметров препаратов комбинированного действия для терапии вирусных и нейродегенеративных заболеваний. Были изучены пути образования свободных радикалов, рассмотрены антиоксидантные подходы в терапии различных заболеваний. С использованием предложенных потенциометрических методов была исследована антиоксидантная (АОЕ) и антирадикальная (АРЕ) емкость синтезированных триазолов и имидазолов, модифицированных полифенолами. АОЕ определяли потенциометрическим методом с использованием окислителя нерадикальной природы – K3[Fe(CN)6]/K4[Fe(CN)6], АРЕ оценивали потенциометрическим методом с использованием радикал-генерирующей системы 2,2´-азобис(2-метилпропионамидин) дигидрохлорида (ААРН). Стехиометрические коэффициенты ингибирования изученных триазолов принимают значения от 0 до 15, имидазолов от 0 до 5 в зависимости от количества активных групп в молекуле антиоксиданта, их расположением и с механизмом обрыва цепей на антиоксиданте. Были проведены корреляционные исследования с применением независимых спектрофотометрических методов. / Objective of the work: comprehensive study of integral antioxidant parameters of combined action drugs for the treatment of viral and neurodegenerative diseases. We have considered ways to form free radicals and antioxidant approaches in therapy of various diseases. In the process of work we investigated the antioxidant parameters adducts of triazole and imidazoles modified with polyphenols. Particularly, the determination of antioxidant capacity with oxidizing agents of a radical (2,2'-azobis (2-methylpropionamidine) dihydrochloride (AAPH)) and non-radical nature (K3[Fe(CN)6]/K4[Fe(CN)6) was performed by using the potentiometric method. Stoichiometric inhibition coefficients of the studied triazoles take values from 0 to 15, imidazoles – from 0 to 5, depending on the number of active groups in the antioxidant molecule, their location and the mechanism of chain termination on the antioxidant. Spectrophotometric studies were carried out using the reactions of the interaction of antioxidants with a stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and reagent Folin-Ciocalteu to confirm the correctness of the results.
342

Optical spectroscopic microscopies study of nano-to-submicron scale structural alterations in human brain cells/tissues and skin fibroblasts due to brain diseases using mesoscopic physics

Alharthi, Fatemah 08 December 2023 (has links) (PDF)
Optical scattering techniques are suitable probes for studying weak disordered refractive index media such as biological cells and tissues. Several brain diseases accompany the nano-to-submicron scales’ structural alterations of the basic building blocks of cells/tissues in the brain and skin fibroblasts. For example, several molecular modifications such as DNA methylation, and histone degradation occur in cells earlier than morphological changes detectable at a microscopic level. These alterations also change the refractive index structures of the cells/tissues at the nano-to-submicron scales. Unfortunately, traditional methods do not allow the detection of these alterations in the early stages of diseases. Recent developments in mesoscopic optical physics-based techniques can probe these alterations. Particularly, mesoscopic light transport and localization approaches enable the measurements and quantifications of the degree of structural alterations in the cells/tissues and unprecedented information on progressive brain diseases. This dissertation provides a detailed study of the structural changes at nano-to-submicron levels in human brain cells/tissues and human skin fibroblasts in two major neurodegenerative diseases, Alzheimer’s disease (AD) and Parkinson's disease (PD), using dual spectroscopic imaging techniques, namely partial wave spectroscopy (PWS) for light transport and inverse participation ratio (IPR) for weak light localization. In particular, a nanoscale-sensitive advanced PWS technique is used to quantify the structural alterations in cells/tissues. Further, the IPR technique is used to quantify molecular-specific mass density alterations within cells using their light localization properties via confocal imaging. These dual optical scattering techniques were utilized to measure the degree of structural disorders, termed ‘disorder strength’, by distinguishing the diseased cells/tissues from normal ones in the human brain and human skin fibroblasts due to neurodegenerative diseases. Our results show that the degree of structural disorder (����) increases in the affected cells and tissues relative to the normal, both at the cellular/tissue level and in the DNA molecular mass density structural levels. The results of the studies strongly reveal that the degree of structural disorder strength (����) is an effective biomarker/numerical indicator for brain disease diagnostics.
343

Casein kinase 1 isoforms in degenerative disorders

Kannanayakal, Theresa Joseph 01 December 2004 (has links)
No description available.
344

Complex Dietary Interventions to Slow Rates of Aging

Aksenov, Vadim 01 September 2014 (has links)
<p>Aging erodes motivation, cognition, sensory modalities and physical capacities, effectively depleting quality of life. Declining sensory, cognitive and motor function are reliable biomarkers of aging and mortality risk. These declines are associated with dysregulation of systemic and cellular processes. We developed a complex dietary supplement (DSP) designed to ameliorate five mechanisms of aging (oxidative processes, inflammation, mitochondrial function, insulin resistance and membrane integrity). Remarkably, normal mice fed the DSP retained youthful functionality into old ages, reflecting slower aging rates. Marked improvements in motor function, memory capacity, spatial learning, muscle strength, visual acuity, olfaction, fecundity and important behavioral functions were observed in aging supplemented mice. Conversely, untreated control animals showed age-related declines in all of the above. Functional improvements were associated with reduced oxidative damage, elevated mitochondrial activity, positive cellular energy balance, improved glucose tolerance, boosted neurotransmitters, greater synaptic density and higher neuronal numbers throughout the brain. A 30% reduction in cancer rates was also documented for DSP treated p53+/- mice. The vast functional benefits greatly exceed the modest longevity extension (11%) in normal supplemented mice. For aging humans, maintaining functionality and performance into later years may provide greater socioeconomic and health benefits than simply prolonging lifespan. Implications of these findings extend to common age-related pathologies including dementia and neurodegenerative diseases, diabetes, cancer, sarcopenia and age-related macular degeneration. Although identifying the role of specific ingredients remains outstanding, results provide proof of principle that complex dietary cocktails can powerfully ameliorate biomarkers of aging and modulate mechanisms considered ultimate goals for aging interventions.</p> / Doctor of Philosophy (PhD)
345

A quantitative interaction screen for neurodegenerative disease proteins

Hosp, Fabian 07 February 2013 (has links)
Der erste Teil dieser Arbeit beschreibt die Durchführung eines quantitativen Ansatzes zur Detektion von Protein-Protein-Interaktionen (PPI) mit einem Schwerpunkt für Proteine, die in vier häufigen neurodegenerativen Krankheiten eine Rolle spielen: die Alzheimer-, Parkinson- und Huntington-Krankheit, sowie die spinozerebelläre Ataxie Typ 1 (SCA1). Die Interaktionsstudie kombiniert die stabile Isotopen-Markierung von Aminosäuren in der Zellkultur mit der Affinitätsaufreinigung von Proteinen und hochauflösender Massenspektrometrie. Dieser Ansatz zielt darauf ab, systematisch die Interaktionspartner von gesunden und krankheitsassoziierten Proteinvarianten zu identifizieren und zu quantifizieren. Darüber hinaus wurde das quantitative Interaktionsverfahren genutzt, um zu prüfen ob PPI durch krankheitsassoziierte Mutationen beeinträchtigt werden. Neben der Validierung möglicher Nebeneffekte, sowie dem Vergleich mit Informationen über PPI aus der Literatur, wurde ein Teil der identifizierten Interaktoren durch zusätzliche Koimmunopräzipitations-Experimente in zwei verschiedenen Zelllinien bestätigt. Mit Hilfe von Drosophila SCA1-Krankheitsmodellen und in Kombination mit RNAi-basierter Stummschaltung identifizierter Interaktoren wurde festgestellt, dass ein großer Teil der Kandidaten Neurodegeneration in vivo beeinflusst. Zusätzlich wurden die Alzheimer-spezifischen PPI-Daten auf genomweite Assoziationsstudien übertragen. Bemerkenswerterweise waren Polymorphismen in einzelnen Nukleotiden in den Genen zugehöriger Interaktoren wahrscheinlicher mit solchen Genen assoziiert, die eine Prädisposition für die Alzheimer-Krankheit haben, als mit zufällig ausgewählten Genen. Schlussendlich konnten Folgeexperimente für zwei ausgewählte Interaktionspartner den Nachweis für eine bislang unbekannte Rolle der N-Glykosylierung und einen neuen Zusammenhang zwischen dem RNA-bindenden Protein LRPPRC und mitochondrialer Dysfunktion in der Alzheimer-Krankheit vorlegen. / The first part of the present thesis describes the establishment of a quantitative protein-protein interaction (PPI) screen with a focus on proteins involved in four common neurodegenerative diseases (NDDs): Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington’s disease (HD) and spinocerebellar ataxia type 1 (SCA1). The interaction screen combines stable-isotope labeling by amino acids in cell culture (SILAC) with protein affinity purification and high-resolution mass spectrometry. This approach aims to systematically identify and quantify interaction partners of normal and known disease-associated variants of proteins involved in NDDs. Moreover, the quantitative interaction screen was employed to study how PPIs are affected by disease-associated mutations. Along with validation of possible off-target effects and comparison of the data with literature-reported PPIs, a subset of identified interactors was validated by additional co-immunoprecipitation experiments in two different cell lines. Utilizing Drosophila models for SCA1 in combination with RNAi-mediated silencing of identified interactors, a large fraction of candidates was observed to also affect neurodegeneration in vivo. In addition, AD-specific PPI data was mapped to patient cohort data obtained from genome-wide associations studies. Notably, single-nucleotide polymorphisms in the genes of interactors of the disease-associated protein variants were more likely associated with susceptibility to AD than randomly selected genes. Finally, functional follow-ups for two selected interaction partners provided evidence for a yet unreported role of N-linked glycosylation in AD, and a novel link to mitochondrial dysfunction in AD by means of the RNA-binding protein LRPPRC.
346

Molecular thermodynamic aspects of dissipative structures in oncology, inflammatory and degenerative processes of Central Nervous System diseases / Aspects thermodynamiques moléculaires des structures dissipatives en oncologie, processus inflammatoires et dégénératifs des maladies du système nerveux central

Vallée, Alexandre 13 December 2017 (has links)
Le métabolisme énergétique est le principal facteur déterminant de la viabilité cellulaire. Les maladies présentent de nombreuses anomalies métaboliques et énergétiques. En effet, les cellules altérées proviennent de procédés exergoniques et émettent de la chaleur vers leur environnement proche. De nombreux processus irréversibles peuvent se produire en modifiant le taux de production d'entropie. Ce niveau représente une quantité thermodynamique qui mesure ces processus irréversibles. Le niveau d'entropie est augmenté par plusieurs anomalies métaboliques et thermodynamiques dans les tumeurs cérébrales, les processus inflammatoires et les maladies neurodégénératives. Les travaux de recherche de cette thèse ont démontré et mis en évidence l'existence d'une diaphonie entre la voie canonique WNT/beta-caténine et le PPAR gamma qui joue un rôle majeur dans la reprogrammation du métabolisme de l'énergie cellulaire entre la phosphorylation oxydative, la glycolyse aérobie et la glycolyse anaérobie, dont le point d'équilibre de cette diaphonie entre ces voies moléculaires varie selon les maladies. Ces maladies sont des structures dissipatives, qui échangent de l'énergie ou de la matière avec leur environnement. Ce sont des systèmes ouverts, loin de l'équilibre thermodynamique qui opèrent sous un régime non linéaire évoluant vers des états non stationnaires. La thermodynamique loin de l'équilibre est une notion axée sur les rythmes circadiens. En effet, les rythmes circadiens participent directement à la régulation de cette diaphonie étudiée. Celle-ci représente une cible innovante dans le cadre l'imagerie moléculaire pour le diagnostic positif et différentiel de ces maladies. / Energy metabolism is the primary determinant of cellular viability. Diseases are the sites of numerous metabolic and energetic production abnormalities. Indeed, the altered cells are derived from exergonic processes and emit heat that flows to the surrounding environment. Many irreversible processes can occur through changing the rate of entropy production. This rate represents a thermodynamic quantity that measures these irreversible processes. Entropy rate is increased by several metabolic and thermodynamics abnormalities in brain tumors, inflammatory processes and neurodegenerative diseases. The research works of this thesis have demonstrated and highlighted the existence of a crosstalk between canonical WNT/beta-catenin pathway and PPAR gamma which plays a major role in the reprogramming of cellular energy metabolism between oxidative phosphorylation, aerobic glycolysis and anaerobic glycolysis, of which the equilibrium point of crosstalk between these molecular pathways varies according to tumor, inflammatory and neurodegenerative diseases. These diseases are dissipative structures, that exchange energy or matter with their environment. They are open systems, far-from the thermodynamic equilibrium that operate under non-linear regime evolving to non-stationary states. Far-from-equilibrium thermodynamics are notions driven by circadian rhythms. Indeed, circadian rhythms directly participate in regulating the crosstalk of the studied molecular pathways. This crosstalk represents an innovative therapeutic target, and molecular data usable for molecular imaging in both positive and differential diagnosis of these diseases.
347

Espectro clínico-mutacional y estudios de correlación genotipo-fenotipo en la población española afectada de lipofuscinosis neuronal ceroidea

Pérez Poyato, María del Socorro 02 July 2012 (has links)
Las lipofuscinosis neuronal ceroidea (LNCs) constituyen uno de los grupos de enfermedades neurodegenerativas de herencia autosómica recesiva más frecuentes en la infancia. Presentan variabilidad en la edad de inicio y comparten amplio espectro fenotípico: epilepsia, déficit visual, deterioro motor y cognitivo progresivos con fallecimiento a edad precoz. Se han identificado ocho genes responsables de las diferentes formas clínicas en la edad pediátrica (CLN10/CTSD, CLN1/PPT1, CLN2/TPP1, CLN3, CLN5, CLN6, CLN7/MFSD8 y CLN8). El análisis mutacional permite asociar el defecto genético a cada una de las formas clínicas: congénita, LNCC (CLN10); infantil, LNCI (CLN1); infantil tardía, LNCIT (CLN2); juvenil, LNCJ (CLN3); variante infantil tardía finlandesa, vLNCITFin (CLN5); variante infantil tardía juvenil precoz, vLNCITJuv (CLN6); variante infantil tardía turca, vLNCITTur (CLN7) y variante infantil tardía epilepsia del norte con retraso mental, EPMR - variante infantil tardía (CLN8). Nos proponemos, a través de los estudios realizados en los pacientes españoles con LNC, profundizar en el conocimiento de los aspectos clínicos y moleculares de este grupo de enfermedades, determinar el espectro mutacional de los genes CLN1, CLN2, CLN3, CLN5 y CLN7 y establecer una adecuada correlación genotipo-fenotipo en la población pediátrica de nuestro país. Desde el año 1974-2011 se estudiaron 6 pacientes con LNCI (5 núcleos familiares). Desde el año 1979-2011 se estudiaron 12 pacientes con LNCIT (10 núcleos familiares). Desde el año 1975-2010 se estudiaron 24 pacientes con LNCJ, divididos en 2 grupos: variante (11 pacientes) con mutaciones en el gen CLN1 y clásico (13 pacientes) con mutaciones en el gen CLN3. Se describieron 3 pacientes con vLNCITFin y uno con vLNCITTur. Se creó una base de datos clínica con 50 ítems. Para el estudio estadístico se utilizó la prueba de Kaplan-Meier. Los pacientes con LNCI, iniciaron la enfermedad entre los 8-15 meses con retraso en el desarrollo motor y marcha inestable. La epilepsia puede aparecer en cualquier momento. La LNCI se caracteriza por un severo y progresivo curso clínico y en nuestra población, la mutación V181M en el gen CLN1 está asociada con el fenotipo más severo de la enfermedad. La LNCIT se inició entre los 18 meses y los 3.7 años con retraso del lenguaje y convulsiones febriles simples seguidas de epilepsia. El trastorno de aprendizaje y la ataxia ocurrieron a los 4 años. La regresión clínica se inició con una pérdida de las frases, seguido de pérdida de la deambulación. Todos los pacientes desarrollaron epilepsia mioclónica continua. La LNCIT presenta un curso clínico muy homogéneo y se demuestra heterogeneidad genética en nuestra población. La forma variante de LNCJ se inició con retraso / regresión del lenguaje y dificultades de aprendizaje mientras que la forma clásica se inició con déficit visual. La regresión clínica se inició con una pérdida de las frases seguida por una pérdida de la deambulación durante la adolescencia en el grupo variante y durante la edad adulta el grupo clásico. El curso clínico es más severo y progresivo en pacientes con mutaciones en el gen CLN1 que en el gen CLN3. La mutación V181L en el gen CLN1 fue identificada en homocigosis en 9 pacientes pertenecientes a 4 familias consanguíneas, no relacionadas, todas de etnia gitana. Se considera la posibilidad de realizar un diagnóstico precoz de LNCJ en base a la sintomatología inicial y la edad de inicio. El índice de progresión de la enfermedad orienta hacia los fenotipos causados por mutaciones en los genes CLN1 / CLN3 y el diagnóstico definitivo deberá confirmarse mediante el análisis mutacional de dichos genes. Se ha elaborado un protocolo diagnóstico que permite realizar estudios de correlación genotipo-fenotipo y amplía el espectro clínico-mutacional en la población española afectada de lipofuscinosis neuronal ceroidea. / Neuronal ceroid lipofuscinosis (NCLs) is one of the most common groups of progressive neurodegenerative diseases in childhood. Eight disease genes causing NCL in childhood have been identified: CLN10/CTSD, CLN1/PPT1, CLN2/TPP1, CLN3, CLN5, CLN6, CLN7/MFSD8, and CLN8. The main objective was to assess the natural history of the disease and to establish phenotype/genotype correlations in Spanish patients with NCL. Infantile neuronal ceroid lipofuscinosis (INCL) is caused by mutations in the CLN1/PPT gene. The age at disease onset in six Spanish patients with INCL ranged from 8 to 15 months. Delayed motor skills and ataxia were the initial symptoms. The V181M mutation in the CLN1 gene was found in homozygosis which is associated with the most severe INCL phenotype. Late infantile neuronal ceroid lipofuscinosis (LINCL) is caused by mutations in the CLN2. The clinical outcome in 12 Spanish patients reported the age at onset of clinical symptoms ranged from 18 months to 3.7 years, and they included delayed speech and simple febrile seizures followed by epilepsy. Clinical regression was initiated by loss of sentences followed by loss of walking ability. The clinical progression of LINCL was relatively homogeneous and genetic heterogeneity was demonstrated in the 10 families studied. Juvenile neuronal ceroid lipofuscinosis (JNCL) is usually caused by a 1.02-kb deletion in the CLN3 gene and mutations in the CLN1 gene may be associated with a variant form of JNCL (vJNCL). To assess the natural history of the disease, 24 Spanish patients with JNCL were studied. Patients were classified into the groups of vJNCL with mutations in the CLN1 gene (n= 11) and classic JNCL (cJNCL) with mutations in the CLN3 gene (n=13). Patients with vJNCL showed a more severe and progressive clinical course than those with cJNCL. The rate of disease progression may be useful to diagnose vJNCL or cJNCL, which should be confirmed by molecular studies in CLN1/CLN3 genes. Three unrelated patients with Finnish variant late infantile (CLN5) and another patient with Turkish variant late infantile (CLN7) were described. The diagnostic algorithm is a useful tool for the diagnosis of the patients with NCL and the correlation genotype-phenotype studies in Spain.
348

Vývoj, optimalizace a validace analytické metody na stanovení neurotoxinu beta-N-methylamino-L-alaninu ve vodě a sinicích pomocí LC/MS

HOŘEJŠÍ, Karel January 2018 (has links)
This master thesis deals with the development, optimization and validation of an analytical method for determination of neurotoxin -N-methylamino-L-alanine in pond water and cyanobacteria using LC/MS. Firstly, basic parameters of the analytical method developed within authors´s bachelor thesis were verified. Following parameters were selected for verification: selection of suitable MRM transitions, voltage applied to S-lens and F-lens and standardized collision energy. Secondly, the system suitability testing was performed. Thirdly, the analytical method was successfully validated. Then, the testing and optimization of solid phase extraction for analysis of water samples were carried out. The pH of sample solution and composition of elution solution were chosen for the optimization. In addition, the trichloroacetic acid extraction with acid hydrolysis for cyanobacterial samples was carried out too. Finally, both solid phase extraction and trichloroacetic acid extraction were evaluated and applied to the analysis of real samples.
349

Involvement of sigma receptors and thri ligands in the biology of cancers / Implication des récepteurs sigma et de leurs ligands dans la biologie des cancers

Megalizzi, Véronique 30 June 2011 (has links)
Parmi les tumeurs cérébrales primaires, les gliomes sont les tumeurs les plus fréquemment rencontrées. Les glioblastomes (GBM) représentent 60 à 70% de ces tumeurs et malgré de récents progrès dans leur traitement, leur pronostic reste sombre. Les gliomes malins sont caractérisés par une prolifération cellulaire importante, un taux élevé de néo-angiogenèse et une migration diffuse des cellules tumorales gliales dans le parenchyme cérébral, ce qui rend impossible une résection chirurgicale complète. De plus, les cellules gliales tumorales migrantes opposent une résistance particulière aux traitements chimiothérapiques de type pro-apoptotique, causant une récidive quasi inévitable de ce type de tumeur. La compréhension des aspects moléculaires à la base de la prolifération, de la migration et de la chimiorésitance des cellules gliales tumorales est donc essentielle pour élaborer des approches ciblées capables d’entraver ces processus. La littérature mentionne plusieurs stratégies qui permettraient, en théorie, de court-circuiter la résistance à l’apoptose des cellules tumorales gliales migrantes. Il s’agirait entre autres :<p>- de réduire le taux d’activation des voies de signalisation contrôlées par PI3K /Akt /mTOR et NFkappaB, qui diminuerait le taux de croissance des gliomes malins, ainsi que le taux de migration des cellules tumorales isolées dans le parenchyme cérébral;<p>- de réduire le taux de migration des cellules tumorales gliales afin de restaurer un certain degré de sensibilité à des agents chimiothérapiques pro-apoptotiques;<p>- d’endiguer l’export des agents chimiothérapiques par les pompes à efflux surexprimées dans les gliomes <p>- d'induire d’autres processus de mort cellulaire que l’apoptose, car les cellules tumorales gliales migrantes sont plus sensibles à d’autres formes de mort cellulaire.<p>Ces besoins de nouvelles stratégies thérapeutiques ont motivé ce travail qui se focalisera sur le potentiel antitumoral des ligands du R-sigma1 dans les glioblastomes. Ainsi, nous montrerons que les ligands des Rs-sigma sont capables de produire certains des effets visés dans les stratégies ci-dessus, dont la réduction de la prolifération et de la migration des cellules cancéreuses avec une certaine potentialisation des chimiothérapies. Ces propriétés ouvrent de nouvelles perspectives en thérapie anticancéreuse pour cette famille de ligands, dont plusieurs membres sont déjà utilisés depuis de nombreuses années comme antipsychotique. / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished
350

Interactions acétylcholine-dopamine dans les maladies neurodégénératives : approche d’imagerie moléculaire / Acetylcholine-dopamine interactions in neurodegenerative diseases : molecular imaging approach

Mazère, Joachim 05 December 2011 (has links)
Le rôle que pourrait jouer l’interaction des systèmes cholinergiques (ACh) et dopaminergiques (DA) semble crucial dans la physiopathologie de certaines maladies neurodégénératives, en particulier dans la démence à corps de Lewy (DCL). Ce travail de thèse se propose de valider un protocole d’imagerie moléculaire en tomographie d’émission monophotonique, consistant en un marquage de l’ACh et de la DA chez un même individu, afin de pouvoir étudier in vivo les interactions ACh/DA.Après avoir mis au point chez des sujets âgés et des patients atteints de maladie d’Alzheimer une méthode d’imagerie cérébrale quantitative des neurones ACh utilisant un radioligand sélectif du transporteur vésiculaire de l’ACh, le [123I]-IBVM, et basée sur une modélisation pharmacocinétique, nous avons montré le potentiel de cette méthode à mettre en évidence une atteinte différentielle des circuits ACh dans la Paralysie Supranucléaire Progressive et l’Atrophie Multisystématisée. Dans la dernière partie de ce travail de thèse, nous avons pour la première fois réalisé un double marquage des systèmes ACh et DA dans la DCL, en utilisant, en plus du [123I]-IBVM, un radioligand sélectif du transporteur de la dopamine et validé en routine clinique, le [123I]-FP-CIT. En parallèle, une étude comportementale évaluant la présence d’hallucinations, de fluctuations cognitives, d’altérations des rythmes circadiens ainsi qu’un bilan des performances neuropsychologiques, ont été menés. Cette étude est actuellement en cours de réalisation. Les tous premiers résultats montrent l’existence de liens cohérents entre les données d’imagerie moléculaire et les données cliniques. / The question of how acetylcholine (ACh) and dopamine (DA) could be involved together in the pathophysiology of some neurodegenerative disorders is essential, particularly in dementia with Lewy bodies (DLB). The present study aims at assessing an in vivo molecular imaging method of both ACh and DA brain systems using single photon emission computed tomography. In the first part of the present study, a method based on pharmacokinetic analysis making it possible to quantify ACh neurons in vivo, using [123I]-IBVM, a specific radioligand of vesicular acetylcholine transporter, was developed and validated in healthy subjects and Alzheimer’s disease patients. Then, we showed the ability of our method to demonstrate a differential alteration of ACh pathways in Progressive Supranuclear Palsy and Multiple System Atrophy patients. In the last part of this study, we imaged for the first time both ACh and DA systems in DLB patients, using not only [123I]-IBVM, but also [123I]-FP-CIT, a specific radioligand of dopamine transporter. Concomitantly, a behavioral exploration of hallucinations, fluctuating cognition and disturbances of circadian rhythms was achieved in these patients, as well as a neuropsychological examination. This study is currently in progress. The first results show consistent links between imaging and clinical data.

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