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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.
71

Ultrastructural Studies of the Airway Epithelium in Airway Diseases

Shebani, Eyman January 2006 (has links)
<p>Ultrastructural studies of airway epithelium in airway disease are important for diagnosis and understanding the underlying pathology which helps clinicians to improve the patients' treatment.</p><p>Airway biopsies from a 5-month old boy with respiratory problems and gastro-oesophageal reflux were studied by transmission electron microscopy (TEM). The tracheal columnar cells showed accumulation of lamellar bodies, indicative of lysosomal storage disease. The patient was diagnosed with Gaucher disease type 2.</p><p>Shedding of airway epithelial cells is commonly found in asthma. The attachment of these cells to the basal lamina was investigated by TEM of biopsies from patients with asthma and healthy controls. The contact area between columnar cells and basal lamina in asthmatics was significantly less than in controls. Attachment of columnar cells to the basal lamina occurs mainly indirectly, via desmosomal attachment to basal cells. </p><p>Primary ciliary dyskinesia (PCD) is a congenital disease. It is important to differentiate PCD from acquired (secondary) ciliary dyskinesia (SCD). The number of dynein arms determined by TEM was 1.5 and 1.4 for outer and inner dynein arms, respectively in PCD, versus 7.9 and 5.2 for controls and 8.1 and 5.9 in SCD. Compared to PCD patients, SCD patients have more structurally abnormal cilia. A significant difference was found in orientation of the central microtubule pair between PCD and SCD, but also overlap. </p><p>Leukotriene receptor antagonists are a new treatment for asthma. Both corticosteroids and montelukast caused apoptosis and necrosis of airway epithelial cells, and reduced the expression of intercellular adhesion molecule-1. Treatment of cells with tumor necrosis factor-α or interferon-γ reduced the fraction of the lateral cell membrane occupied by desmosomes and this effect was counteracted by corticosteroids. </p>
72

Ultrastructural Studies of the Airway Epithelium in Airway Diseases

Shebani, Eyman January 2006 (has links)
Ultrastructural studies of airway epithelium in airway disease are important for diagnosis and understanding the underlying pathology which helps clinicians to improve the patients' treatment. Airway biopsies from a 5-month old boy with respiratory problems and gastro-oesophageal reflux were studied by transmission electron microscopy (TEM). The tracheal columnar cells showed accumulation of lamellar bodies, indicative of lysosomal storage disease. The patient was diagnosed with Gaucher disease type 2. Shedding of airway epithelial cells is commonly found in asthma. The attachment of these cells to the basal lamina was investigated by TEM of biopsies from patients with asthma and healthy controls. The contact area between columnar cells and basal lamina in asthmatics was significantly less than in controls. Attachment of columnar cells to the basal lamina occurs mainly indirectly, via desmosomal attachment to basal cells. Primary ciliary dyskinesia (PCD) is a congenital disease. It is important to differentiate PCD from acquired (secondary) ciliary dyskinesia (SCD). The number of dynein arms determined by TEM was 1.5 and 1.4 for outer and inner dynein arms, respectively in PCD, versus 7.9 and 5.2 for controls and 8.1 and 5.9 in SCD. Compared to PCD patients, SCD patients have more structurally abnormal cilia. A significant difference was found in orientation of the central microtubule pair between PCD and SCD, but also overlap. Leukotriene receptor antagonists are a new treatment for asthma. Both corticosteroids and montelukast caused apoptosis and necrosis of airway epithelial cells, and reduced the expression of intercellular adhesion molecule-1. Treatment of cells with tumor necrosis factor-α or interferon-γ reduced the fraction of the lateral cell membrane occupied by desmosomes and this effect was counteracted by corticosteroids.
73

Proteomic Characterization of Induced Developmental Neurotoxicity

Alm, Henrik January 2009 (has links)
The developing brain goes through a number of developmental periods during which it displays an increased sensitivity to exogenous disturbances. On such period is the so called “Brain growth spurt” (BGS) which in humans takes place starting from the third trimester of pregnancy and throughout the first few years of life. The corresponding period in rats and mice is the first postnatal weeks. Exposure to relatively modest concentrations of the brominated flame retardant PBDE-99 during the second week of life in mice causes a more or less permanent impairment in the ability of the animals to adjust properly to environmental changes at adulthood. This “late response on early exposure” reflects the long-term consequences of disrupting the developing brain during a sensitive time period. The cellular mechanisms underlying the behavioral effects are far from clear. To address the initial damage occurring around the time of exposure, the approach used in this thesis is to use proteomics to analyze the effects of PBDE-99 on protein expression soon (24 hours) after exposure of the neonatal mouse on postnatal day (PND) 10.The thesis comprises the effects on the proteome in three distinct brain parts: cerebral cortex, striatum and the hippocampus. In addition, an in vitro model was developed and used to evaluate the PBDE-99 effects on cultured cerebral cortex cells from embryonic rat brains. Gel-based proteomics (2D-DIGE) coupled to MALDI- or ESI-MS has been used throughout for the proteomics experiments, but other techniques aimed at analyzing both proteins and mRNA have also been used to better characterize the effects. Even if the protein complements expressed by the different brain parts and separated with 2D-DIGE are seemingly similar, the effects are apparently specific for the different brain regions. In hippocampus, PBDE induces effects on proteins involved in metabolism and energy production, while the effects in striatum point towards effects on neuroplasticity. PBDE-99 changes the expression of cytoskeletal proteins in the cerebral cortex 24 hours after exposure. Interestingly, in vitro exposure of cerebral cortex cells to a PBDE-99 concentration in the same order of magnitude as in the in vivo neonatal brain also induces cytoskeletal effects, in the absence of cytotoxicity. This may suggest effects on regulatory aspects of cytoskeletal dynamics such as those involved in neurite sprouting. This thesis also addresses the problems involved in presenting proteomics data. Many of the available methods and approaches for presenting transcriptomics data are not suitable for isoform rich protein data. Modifications of existing methods and the development of a new approach (DEPPS) is also presented. Most importantly, the thesis presents the application and usefulness of proteomics as hypothesis generating techniques in neurotoxicology.
74

Association of genetic variants and the susceptibility to abnormal involuntary movements and tardive dyskinesia (TD) in Xhosa schizophrenia patients

Hitzeroth, Angelika 03 1900 (has links)
Thesis (MSc (Genetics))—University of Stellenbosch, 2007. / No obvious explanations exist for the development of abnormal involuntary movements (AIM), but several hypotheses have been proposed for tardive dyskinesia (TD) development. Since TD seems to have a genetic basis, several genetic variants have been investigated in TD development in various populations. Few studies have focused on African populations. This study focused on genetic variants (previously investigated in other populations) and the development and severity of AIM and TD in a Xhosa schizophrenia population. Genotype and allele frequencies determined were compared to those described in the literature for other populations. Following a report of an association between Ala-9Val and schizophrenia in a Turkish population, this study subsequently investigated this association in the Xhosa population. MnSOD Ala-9Val was genotyped using HEX-SSCP analysis and the DRD3 Ser9Gly variant was genotyped using restriction enzyme digestion by MscI. Genotyping was followed by statistical comparisons of the various groups, as well as association analyses between the variant and schizophrenia (only for MnSOD), AIM, or TD development and severity. The groups included a Xhosa schizophrenia group, a subgroup of the Xhosa schizophrenia group that had AIM (AIM+) and did not have AIM (AIM-), a subgroup of the AIM+ group that had TD (TD+), and a healthy Xhosa control group. A possible interaction between Ala-9Val and Ser9Gly in the development of AIM and TD was also investigated. Lastly, it was attempted to genotype CYP2D6*4, CYP2D6*10 and CYP2D6*17 using various PCR methods followed by restriction enzyme analysis. MnSOD Ala-9Val genotype and allele frequencies were similar to those of the Turkish population, but differed to those of the Asian populations. No association between Ala-9Val and the development and severity of schizophrenia was found. However, a relationship between genotype and AIM or TD development was observed, as well as an association between TD severity and Ala- 9Val genotype. DRD3 Ser9Gly genotype and allele frequencies were similar to those of the African American population, but differed from other populations. No significant association between Ser9Gly and the development and severity of AIM or TD was detected, nor was an interactive effect between Ala-9Val and Ser9Gly in AIM or TD development observed. The genotyping of CYP2D6 proved difficult and these variants could therefore not be analysed. The CYP2D6*4 genotype and allele frequencies that could be determined from some samples, were similar to the frequencies described previously for African populations. While we did not find an association between Ser9Gly in TD or AIM development and severity, nor an interaction between Ala-9Val and Ser9Gly, we did observe a relationship between Ala-9Val and AIM or TD development and TD severity. The effect of this variant is probably small and other variants, specifically those in genes involved in free radical removal should be investigated in combination with Ala-9Val. With regard to CYP2D6 it is suggested that high-throughput genotyping methods (e.g. microarray technology) should be used in the future. This will enable simultaneous genotyping of several variants and can be used in various populations. This study is the first of its kind by focusing on the unique South African Xhosa population and TD or AIM development.
75

Syndrome de tremblements épisodiques de la tête chez le bouledogue anglais : prévalence, sémiologie et investigation diagnostique

Dugas, Stephanie 12 1900 (has links)
Mémoire en neurologie vétérinaire
76

Avaliação dos efeitos promovidos pelo chumbo, selênio e/ou sacarose em parâmetros oxidativos em roedores / Evaluation of lead, selenium and/or sucrose- effects on oxidative parameters in rodentes

Perottoni, Juliano 16 March 2006 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Lead is a common occupational and environmental hazard, and it is known that can be toxic to several species of animals, and experimental studies support the theory of oxidative damage in lead toxicity. Literature data have shown that high- sucrose diet can increase oxidative stress. Oxidative stress is related with several pathologies, such as enzyme inhibitions to behavioral disorders. Organoselenium compounds, Ebselen and diphenyl diselenide have described antioxidant properties, such as thiol- peroxidase activity. In a sub-chronic protocol of intoxication (ARTICLE 1), was determined whether these selenocompounds were effective to restore the leadtoxicity in mice. Lead acetate injection with subsequent injection of Ebselen only reduce the hepatic levels of non- protein thiol groups (NPSH). The treatment with Ebselen also reduced TBARS levels in kidney. Whereas lead inhibited δ-ALA-D activity in all tissues, Ebselen performed a recovery brain enzyme inhibition. It was also observed that metal or selenocompounds did not change glutamate uptake, whereas lead plus Ebselen showed an increase on this parameter. The results of this study indicate that δ-ALA-D inhibition antecedes the overproduction of reactive oxygen species in a short- term protocol of mice intoxication. In other study (MANUSCRIPT 2), where treated female rats for 12 months with lead acetate and/or sucrose- diet, to evaluate whether simultaneous exposure to these agents could enhance the appearance of orofacial dyskinesia, or could disturb the locomotor behavior. The aged rats demonstrated an increased orofacial dyskinesia, whereas sucrose ingestion was not associated with this parameter. The association between lead and sucrose caused a reduction on orofacial dyskinesia, and can be related to an adaptation after long-term exposure to pro-oxidant agents. In MANUSCRIP 3, a study carried out for 24 months of sucrose diet and lead exposure, where observed that the effects were tissue- specific. Another result obtained in this study was an increased spleen ALA-D activity, it is a vi contraditory result, because this enzyme is a classical marker of lead toxicity. These results may indicate that ALA-D is an indicator of acute or sub-chronic lead exposure and that some adaptations to lead and/or sucrose toxicity occur after long-term exposure to these substances. / O chumbo apresenta um risco ocupacional e ambiental, e sabe-se que pode ser tóxico para diversas espécies de animais. Diversos estudos experimentais confirmam a teoria de dano oxidativo na toxicidade promovida pelo chumbo. Dados da literatura tem mostrado que dietas ricas em sacarose podem incrementar o estresse oxidativo. Estresse oxidativo está relacionado com diversas patologias, desde inibições enzimáticas até distúrbios comportamentais. Compostos orgânicos de selênio, ebselen e disseleneto de difenila tem uma descrita atividade antioxidante, semelhante à atividade tiolperoxidase. Em um protocolo de intoxicação sub- crônica (ARTIGO 1), determinou-se se estes compostos seriam efetivos para reverter a toxicidade promovida pelo chumbo em camundongos. Injeções de acetato de chumbo, com subseqüentes injeções de ebselen reduziram apenas os níveis hepáticos de grupos tiólicos não protéicos (NPSH). O tratamento com ebselen também reduziu os níveis de TBARS no rim. Enquanto o chumbo inibiu a atividade da δ-ALA-D em todos os tecidos, o ebselen reverteu a inibição enzimática no cérebro. Também foi observado que o metal ou os organocompostos de selênio não modificaram a captação de glutamato, enquanto o ebselen promoveu um aumento neste parâmetro. Os resultados deste estudo indicam que a inibição da atividade da δ-ALA-D antecede a produção de espécies reativas de oxigênio em um protocolo sub- crônico de intoxicação em camundongos. Em outro estudo (MANUSCRITO 2), ratas foram tratadas por 12 meses com acetato de chumbo e/ou dieta rica em sacarose, para avaliar se a exposição simultânea a estes agentes poderia produzir o aparecimento de discinesia orofacia, ou modificar o comportamento locomotor. Os ratos demonstraram um incremento na discinesia orofacial, enquanto a ingestão de sacarose não esteve associada à este parâmetro. A associação entre chumbo e iv sacarose causou uma diminuição na discinesia orofacial, o que pode estar relcionado a uma adaptação após uma prolongada exposição a agentes próoxidantes. No MANUSCRITO 3, foi conduzido um estudo por 24 meses com uma dieta rica em sacarose e exposição ao chumbo, onde foram observados uma especificidade dos efeitos nos tecidos. Outro resultado obtido neste estudo foi um aumento na atividade da δ-ALA-D de baço, o que é um resultado contraditório, uma vez que esta enzima é um clássico marcador de toxicidade por chumbo. Estes resultados podem indicar que a enzima δ-ALAD é um indicador de toxicidade aguda ou sub- crônica, e que pode ocorrer alguma adaptação à toxicidade promovida pela sacarose e/ou pelo chumbo após exposição prolongada a estas substâncias.
77

MECANISMOS BIOQUÍMICOS E MOLECULARES ENVOLVIDOS EM EFEITOS COMPORTAMENTAIS INDUZIDOS POR RESERPINA EM RATOS E C. elegans COM ÊNFASE EM PARÂMETROS OXIDATIVOS E DOPAMINÉRGICOS / BIOCHEMICAL AND MOLECULAR MECHANISMS INVOLVED IN BEHAVIORAL EFFECTS INDUCED BY RESERPINE IN RATS AND C. elegans WITH ENPHASIS IN OXIDATIVE AND DOPAMINERGIC PARAMETERS

Reckziegel, Patrícia 16 January 2015 (has links)
Fundação de Amparo a Pesquisa no Estado do Rio Grande do Sul / Animal models as reserpine are helpful to understand the pathophysiology of several diseases with involuntary movements, as Parkinson s disease (PD), and to search efficient treatments. The present study tested the effects of reserpine on behavioral alterations induced by reserpine in rats and worms, with emphasis in oxidative and dopaminergic parameters, and the effect of the antioxidant gallic acid (GA) in reserpine-exposed rats. As result, reserpine (1mg/Kg, sc, for 3 consecutive days) increased the frequency of vacuous chewing movements (VCMs) in rats in relation to controls, and maintained this increase for at least 3 days after reserpine withdrawal. Treatment with GA (4.5 , 13.5 or 40.5 mg/kg/day, po) for 3 days reverted reserpine-induced increase in VCMs, showing protective effect. Neither reserpine nor GA changed oxidative parameters (TBARS and DCFH-DA oxidation), antioxidant levels (proteic and non-proteic thiol) and the activity of Na+,K+-ATPase (total and α-subunit) in striatum and cortex. Afterward, studies were performed with Caenorhanditis elegans due its several advantages in studies of neurodegeneration and of drugs mechanism of action. L1-larval stage C. elegans were exposed to reserpine (30 ou 60 μM) for different times. Reserpine decreased the survival, development, food intake, locomotor rate on food and dopamine (DA) levels in worms and it had effect on egg laying and defecation cycles. Morphological evaluations of dopaminergic cephalic (CEP) neurons in BY200 worms (with GFP coupled to dat-1 gene) reveled neurodegeneration by: 1) decreased fluorescence intensity, 2) decreased the number of intact neurons, and 3) increased the number of shrunken somas per worm. These effects were unrelated to reserpine s effect on dat-1 gene expression. Interestingly, the reserpine effects on locomotor rate, dopaminergic CEP neurons morphology and dat-1 gene expression were reverted after reserpine withdrawal. Furthermore, reserpine decreased the survival of vesicular monoamine transporter (VMAT) and dat-1 loss-of-function mutant worms, but no of tyrosine hydroxylase (TH, cat-2) and dopaminergic receptors (dop-1, dop-2, dop-3 e dop-4) loss-of-function mutants in relation to wild-type N2 worms. Reserpine also decreased the survival of worms pre-exposed to DA; and it activated SKN-1 detoxification pathway. Moreover, no differences were found in DAT and TH immunoreactivity in striatum of rats treated with reserpine and/or GA. The GA protective effects against reserpine-induced VCMs in rats are probably not related to its antioxidant and antiapoptotic properties or monoamine oxidase (MAO) inhibition. As conclusion, the reserpine decreases DA levels though action on VMAT, and it induces neurotoxicity/neurodegeneration due probably an increase on extracellular DA contents resulted from changes on DAT function. More studies evaluating the reserpine effect on DAT and the GA mechanism of protection are necessary. / Modelos animais como o da reserpina auxiliam no entendimento da fisiopatologia de diversas doenças que se manifestam por movimentos involuntários, como a doença de Parkinson (DP), e na busca por formas de tratamento. O presente trabalho avaliou mecanismos envolvidos na indução de alterações comportamentais induzidas por reserpina em ratos e vermes com ênfase em parâmetros oxidativos e dopaminérgicos, e a ação do antioxidante ácido gálico (AG) em ratos tratados com reserpina. Como resultado, a reserpina (1mg/Kg, sc, por 3 dias consecutivos) aumentou a frequência de movimentos de mascar no vazio (MMVs) em ratos em relação ao controle, e manteve esse aumento por pelo menos 3 dias após o término das administrações da reserpina. O tratamento com AG (4,5 ou 13,5 ou 40,5 mg/kg/day, vo) por 3 dias reverteu esse aumento dos MMVs, mostrando efeito protetor. Nem reserpina nem o AG alteraram os parâmetros avaliados de dano oxidativo (TBARS e oxidação da DCFH-DA), de antioxidantes (tiol protéico e não protéico) e a atividade da Na+,K+-ATPase (total e α-subunidade) no estriado e córtex cerebral. Estudos posteriores foram realizados em Caenorhanditis elegans devido as diversas vantagens oferecidas por esse modelo animal em estudos de neurodegeneração e de investigação do mecanismo de ação de drogas. C. elegans em estágio larval L1 foram expostos a reserpina (30 ou 60 μM) por diferentes tempos. A reserpina reduziu a sobrevivência, o desenvolvimento, a ingestão de alimento, a atividade locomotora na comida e as concentrações de dopamina (DA) nos vermes, e afetou a postura de ovos e tempo entre defecações. Análise da morfologia dos neurônios dopaminérgicos cefálicos (CEP) de vermes BY200 (com GFP acoplado ao gene dat-1) indicam neurodegeneração por: 1) redução da intensidade da fluorescência, 2) redução do número de neurônios intactos e 3) aumento do número de somas atrofiados por verme em relação ao controle. Esses efeitos não estão relacionados a efeitos da reserpina na expressão do gene dat-1. Interessantemente, os efeitos da reserpina na atividade locomotora, na morfologia dos neurônios CEP e na expressão do gene dat-1 foram revertidos após a retirada dos vermes da exposição a reserpina. Em adição, a reserpina reduziu a sobrevivência de vermes deficientes do transportador vesicular de monoaminas (TVMs, cat-1) e do transportador de DA (DAT, dat-1), mas não alterou a sobrevivência de deficientes da tirosina hidroxilase (TH, cat-2) e dos receptores dopaminérgicos (dop-1, dop-2, dop-3 e dop-4) em relação aos vermes selvagens N2. A reserpina também reduziu a sobrevivência de vermes N2 pré-expostos a DA, e ativou a via de detoxificação SKN-1 dos vermes. Alterações na imunoreatividade ao DAT e a TH no estriado de ratos tratados com reserpina e/ou AG não foram encontradas. O efeito protetor do AG nos MMVs induzidos por reserpina em ratos parece não envolver sua atividade antioxidante, antiapoptótica ou na monoaminoxidase (MAO). Como conclusão, a reserpina age no TVMs causando depleção de DA, e causa neurotoxicidade/neurodegeneração dopaminérgica devido provavelmente a um acúmulo de DA no espaço sináptico resultande de uma interferência no funcionamento do DAT. Mais estudos avaliando a ação da reserpina no DAT e o mecanismo de proteção do AG são necessários.
78

Tělesná zdatnost a pohybová aktivita u dětí s primární ciliární dyskinezou / Aerobic fitness and physical activity in children with primary ciliary dyskinesia

Šembera, Martin January 2017 (has links)
Primary ciliary dyskinesia is a rare hereditary disorder with impairment of cilia characterized by chronic cough with sputum, bronchiectasis or pneumonia. Regular exercise training should affect pulmonary function, promote mucociliary clearance and improve quality of life. The aim of this thesis is to compare the aerobic fitness of patients with PCD with a control group.
79

Caractérisation des mécanismes du battement ciliaire dans le cadre du transport mucociliaire normal et pathologique / Characterization of ciliary beat mechanisms under normal and pathological mucociliary clearance

Bottier, Mathieu 30 November 2016 (has links)
L'épuration mucociliaire est la première ligne de défense de l'appareil respiratoire. L'altération de l'épuration mucociliaire se traduit par une stagnation et/ou une accumulation de mucus, conduisant potentiellement à des obstructions plus ou moins partielles et à des infections chroniques des voies aériennes. On compte deux grands types d'altération de l'épuration mucociliaire. Le premier est lié aux caractéristiques du mucus, comme dans le cas de la mucoviscidose. Le deuxième est lié à des anomalies de l'ultrastructure du cil et /ou de son battement regroupées sous le terme de "ciliopathies"qui peuvent être soit innées soit acquises.Ce travail, qui s'inscrit dans le cadre clinique de la problématique des ciliopathies respiratoires et de leur prise en charge, a pour objectif de mieux caractériser, à partir des outils de la Biomécanique, les mécanismes du battement ciliaire (incluant une mesure de l'efficacité globale du battement des cils) et à transférer ces connaissances au profit de la clinique.Pour cela une méthodologie de caractérisation systématique de la mécanique ciliaire à partir de prélèvements biologiques issus de patients observés par vidéo-microscopie à haute vitesse a été développée parallèlement au développement d'un modèle numérique intégrant le couplage entre battement ciliaire et transport de fluide. Cette association entre expériences et modèle numérique a permis de proposer un nouvel index utilisable par les cliniciens pour caractériser l'efficacité du battement ciliaire. Cet index présente l'avantage de ne pas exiger de modification de la pratique clinique concernant la collecte de données biologiques / Mucociliary clearance is the first line of defense of the respiratory tract. Alteration of this clearance leads to a stagnation and/or accumulation of mucus, potentially resulting in more or less partially obstructions and in chronic infections of the airways. There are two main types of mucociliary clearance alterations. The first one is linked to the mucus characteristics, as in cystic fibrosis. The second one is connected to cilium ultrastructure abnormalities and/or ciliary beating defects encompassed by the term of "ciliopathies" which may be primary or acquired.This work, which takes place in the clinical issue of respiratory ciliopathies and their care, aims to better characterize, through biomechanics tools, the mechanisms of ciliary beating (including a measurement of the global efficiency of cilia) and to transfer these knowledges in favor of the clinical management.A methodology of systematic characterization of the ciliary mechanics, from biological samples derived from patients observed through high-speed video-microscopy analysis, has been developed as the same time as the development of a numerical model incorporating the coupling between ciliary beating and fluid motion. This association between experiments and numerical model allowed to propose a new index usable by the clinicians to characterize the ciliary beating efficiency. This index has the advantage of not requiring a modification of the clinical practice of biological data collection
80

Essais de thérapie génique pour la dyskinésie ciliaire primitive / Gene therapy for primary ciliary dyskinesia

Jimenez, Gina Camila 24 November 2016 (has links)
La dyskinésie ciliaire primitive (DCP) est une maladie génétique rare, autosomique récessive, résultant d'un dysfonctionnement des cils de l'épithélium respiratoire. Les patients atteints souffrent d'infections respiratoires chroniques accompagnées de complications évoluant vers l'insuffisance respiratoire, en dépit de traitements antibiotiques et de kinésithérapique à vie. Ils peuvent aussi présenter une hétérotaxie.La première partie de ma thèse a consisté à rechercher des gènes impliqués dans l'hétérotaxie et la DCP. Grâce au séquençage haut-débit, nous avons pu identifier deux nouveaux gènes - MMP21 et RSPH1 - responsables respectivement d'hétérotaxie et de DCP. L'identification de tous les gènes responsables est un préalable indispensable à toute thérapie génique. Dans la deuxième partie, nous avons cherché à développer une thérapie génique in vivo dans le but de restaurer un battement ciliaire normal et ainsi de stopper l'évolution de la maladie. Préalablement, notre laboratoire avait apporté la preuve du concept dans un essai de thérapie génique in vitro impliquant le gène DNAI1. Pour la démonstration in vivo, la lignée Dnahc11iv de souris ayant une mutation du gène Dnahc11 et ayant des cils déficients a été choisie. L'ADNc de DNAH11 (14 kb) a été cloné sous contrôle d'une partie de la séquence du promoteur FOXJ1, suffisante pour limiter l'expression du transgène aux cellules ciliées. Une autre construction a permis de produire des vecteurs dérivés du baculovirus. Un essai de délivrance par voies nasale et trachéale a été réalisé avec succès d'une part avec les vecteurs dérivés du baculovirus et d'autre part avec l'ADNc complexé à des nanoparticules / Primary ciliary dyskinesia (PCD) is a rare autosomal recessive genetic disorder, caused by airway epithelial cilia dysfunction. Patients suffer from chronic respiratory infections along with various organ defects evolving toward respiratory insufficiency, in spite of antibiotic treatment and lifelong physiotherapy. They can also have heterotaxy syndrome. The first part of this work aimed to identify mutations in genes implicated in heterotaxy and PCD. Thanks to next-generation sequencing method, two new genes were identified MMP21 and RSPH1 causing heterotaxy and PCD respectively. The discovery of all causal genes is the base of the development of a PCD therapy system. The second part describes the development and the characterization of tools needed to establish an in vivo gene therapy. The purpose is to restore a normal cilia beating to limit or even stop the disease. First, our laboratory demonstrated the proof-of-concept in an in vitro gene therapy assay for DNAI1. To do so, Dnahc11 deficient mouse model with immotile cilia and PCD symptoms was chosen. Then, to achieve the project, DNAH11 cDNA (14 kb) has been cloned under control of a part of the sequence of the specific promoter (FOXJ1), previously demonstrated as sufficient to limit transgene expression to ciliated cells. Another construction was made to produce baculovirus derived vectors. A cDNA delivery attempt through nasal and tracheal way was done with baculovirus derived vector or DNAH11 cDNA complexed with nanoparticles

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