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Vandenberghe, Michel. "3D whole-brain quantitative histopathology : methodology and applications in mouse models of Alzheimer's disease." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066411/document.
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L’histologie est la méthode de choix pour l’étude ex vivo de la distribution spatiale des molécules qui composent les organes. En particulier, l’histologie permet de mettre en évidence les marqueurs neuropathologiques de la maladie d’Alzheimer ce qui en fait un outil incontournable pour étudier la physiopathologie de la maladie et pour évaluer l’efficacité de candidats médicaments. Classiquement, l’analyse de données histologiques implique de lourdes interventions manuelles, et de ce fait, est souvent limitée à l’analyse d’un nombre restreint de coupe histologiques et à quelques régions d’intérêts. Dans ce travail de thèse, nous proposons une méthode automatique pour l’analyse quantitative de marqueurs histopathologiques en trois dimensions dans le cerveau entier de rongeurs. Les images histologiques deux-dimensionnelles sont d’abord reconstruites en trois dimensions en utilisant l’imagerie photographique de bloc comme référence géométrique et les marqueurs d’intérêts sont segmentés par apprentissage automatique. Deux approches sont proposées pour détecter des différences entre groupes d’animaux: la première est basée sur l’utilisation d’une ontologie anatomique de cerveau qui permet détecter des différences à l’échelle de structures entières et la deuxième approche est basée sur la comparaison voxel-à-voxel afin de détecter des différences locales sans a priori spatial. Cette méthode a été appliquée dans plusieurs études chez des souris modèles de déposition amyloïde afin d’en démontrer l’utilisabilitéHistology is the gold standard to study the spatial distribution of the molecular building blocks of organs. In humans and in animal models of disease, histology is widely used to highlight neuropathological markers on brain tissue sections. This makes it particularly useful to investigate the pathophysiology of neurodegenerative diseases such as Alzheimer’s disease and to evaluate drug candidates. However, due to tedious manual interventions, quantification of histopathological markers is classically performed on a few tissue sections, thus restricting measurements to limited portions of the brain. Quantitative methods are lacking for whole-brain analysis of cellular and pathological markers. In this work, we propose an automated and scalable method to thoroughly quantify and analyze histopathological markers in 3D in rodent whole brains. Histology images are reconstructed in 3D using block-face photography as a spatial reference and the markers of interest are segmented via supervised machine learning. Two complimentary approaches are proposed to detect differences in histopathological marker load between groups of animals: an ontology-based approach is used to infer difference at the level of brain regions and a voxel-wise approach is used to detect local differences without spatial a priori. Several applications in mouse models of A-beta deposition are described to illustrate 3D histopathology usability to characterize animal models of brain diseases, to evaluate the effect of experimental interventions, to anatomically correlate cellular and pathological markers throughout the entire brain and to validate in vivo imaging techniques
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Klinge, Christine [Verfasser]. "Quantitative Strukturanalyse der Mäuselunge mit stereologischen Methoden: Korrelation von Micro-CT und Histologie / Christine Klinge." Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2013. http://d-nb.info/1037834569/34.
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Vandenberghe, Michel. "3D whole-brain quantitative histopathology : methodology and applications in mouse models of Alzheimer's disease." Electronic Thesis or Diss., Paris 6, 2015. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2015PA066411.pdf.
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L’histologie est la méthode de choix pour l’étude ex vivo de la distribution spatiale des molécules qui composent les organes. En particulier, l’histologie permet de mettre en évidence les marqueurs neuropathologiques de la maladie d’Alzheimer ce qui en fait un outil incontournable pour étudier la physiopathologie de la maladie et pour évaluer l’efficacité de candidats médicaments. Classiquement, l’analyse de données histologiques implique de lourdes interventions manuelles, et de ce fait, est souvent limitée à l’analyse d’un nombre restreint de coupe histologiques et à quelques régions d’intérêts. Dans ce travail de thèse, nous proposons une méthode automatique pour l’analyse quantitative de marqueurs histopathologiques en trois dimensions dans le cerveau entier de rongeurs. Les images histologiques deux-dimensionnelles sont d’abord reconstruites en trois dimensions en utilisant l’imagerie photographique de bloc comme référence géométrique et les marqueurs d’intérêts sont segmentés par apprentissage automatique. Deux approches sont proposées pour détecter des différences entre groupes d’animaux: la première est basée sur l’utilisation d’une ontologie anatomique de cerveau qui permet détecter des différences à l’échelle de structures entières et la deuxième approche est basée sur la comparaison voxel-à-voxel afin de détecter des différences locales sans a priori spatial. Cette méthode a été appliquée dans plusieurs études chez des souris modèles de déposition amyloïde afin d’en démontrer l’utilisabilitéHistology is the gold standard to study the spatial distribution of the molecular building blocks of organs. In humans and in animal models of disease, histology is widely used to highlight neuropathological markers on brain tissue sections. This makes it particularly useful to investigate the pathophysiology of neurodegenerative diseases such as Alzheimer’s disease and to evaluate drug candidates. However, due to tedious manual interventions, quantification of histopathological markers is classically performed on a few tissue sections, thus restricting measurements to limited portions of the brain. Quantitative methods are lacking for whole-brain analysis of cellular and pathological markers. In this work, we propose an automated and scalable method to thoroughly quantify and analyze histopathological markers in 3D in rodent whole brains. Histology images are reconstructed in 3D using block-face photography as a spatial reference and the markers of interest are segmented via supervised machine learning. Two complimentary approaches are proposed to detect differences in histopathological marker load between groups of animals: an ontology-based approach is used to infer difference at the level of brain regions and a voxel-wise approach is used to detect local differences without spatial a priori. Several applications in mouse models of A-beta deposition are described to illustrate 3D histopathology usability to characterize animal models of brain diseases, to evaluate the effect of experimental interventions, to anatomically correlate cellular and pathological markers throughout the entire brain and to validate in vivo imaging techniques
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Bélanger, Erik. "Développement et utilisation d'une plateforme d'imagerie optique quantitative, multimodale et non linéaire de la moelle épinière chez les animaux vivants." Doctoral thesis, Université Laval, 2013. http://hdl.handle.net/20.500.11794/24192.
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La microscopie optique chez les animaux vivants est un outil de recherche prometteur pour l’avancement de la neurobiologie. L’imagerie intravitale offre un aperçu en direct de la réponse des cellules individuelles aux dommages affectant le système nerveux. Combinée à la vaste gamme de souris transgéniques disponibles commercialement et compatibles avec différents modèles animaux de maladies neurodégénératives, la microscopie in vivo favorise la compréhension du déroulement des pathologies et du fonctionnement des thérapies. Il est capital de travailler à l’émergence de cet outil, qui se présente comme une stratégie dotée d’un énorme potentiel. Le projet de doctorat décrit dans cette thèse porte donc sur le développement et l’utilisation d’une plateforme de microscopie quantitative, multimodale et non linéaire pour l’imagerie de la moelle épinière chez les animaux vivants. Premièrement, nous avons enrayé la dépendance en polarisation de l’intensité du signal de diffusion Raman cohérente (CARS, « coherent anti-Stokes Raman scattering »), de façon à adapter les images à l’interprétation histologique. Nous avons appliqué cette technique afin d’étudier l’histologie de la myéline de la moelle épinière du rat. En second lieu, nous avons proposé une nouvelle procédure d’analyse d’images compatible avec l’imagerie d’animaux vivants, dans le but de faire de l’histologie des axones myélinisés. Nous avons alors quantifié, dans un modèle de blessure par écrasement d’un nerf, la démyélinisation proximale et la remyélinisation distale au site de lésion ex vivo et in vivo respectivement. Troisièmement, nous montrons que l’imagerie de CARS de la moelle épinière de souris vivantes peut être réalisée avec un microendoscope, et ce tout en conservant sa compatibilité avec le signal de fluorescence par excitation à deux photons. Finalement, nous discutons d’une stratégie de traitement numérique d’images pour réduire les artefacts reliés au mouvement de l’animal. Cette technique permet l’étude histologique de la myéline et la quantification de la motilité des cellules microgliales dans leur environnement natif. En définitive, cette thèse démontre que la microscopie de CARS in vivo progresse peu à peu vers un outil grand public en neurobiologie.Optical microscopy in living animals is a promising research tool for the evolution of neurobiology. Intravital imaging offers a live preview of how individual cells respond to the nervous system damages. Applying in vivo microscopy to a panoply of transgenic mice used with different animal models of neurodegenerative diseases promotes the understanding of the progress of pathologies and the comprehension of how therapies work. It is thus essential to promote the emergence of optical microscopy technologies in living animals because it is a strategy with great potential. Therefore, the project described in this doctoral thesis focuses on the development and use of a microscopy platform for quantitative, multimodal and nonlinear imaging of the spinal cord in living animals. First, we alleviated the polarization dependence of the coherent anti-Stokes Raman scattering (CARS) signal intensity. This strategy makes images more amenable to histological interpretation. With this technique, we studied the histology of myelin in the rat spinal cord. Secondly, we proposed a new image analysis procedure compatible with live animals imaging in order to achieve the histology of myelinated axons. We quantified the demyelination proximal, and remyelination distal to the crush site ex vivo and in vivo respectively. Third, we showed that CARS imaging of the spinal cord in living mice can be achieved with a microendoscope, and this while maintaining compatibility with the two-photon excitation fluorescence signal. Finally, we discuss a digital image processing strategy that reduces imaging artifacts related to movement of the animal. This technique allows the histological study of myelin and the quantification of the motility of microglial cells in their native environment. Ultimately, this thesis demonstrates that in vivo CARS microscopy progresses gradually towards a robust tool for research in neurobiology.
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Emerit, Valérie. "Etude quantitative des images en imagerie de résonance magnétique nucléaire : détermination rapide in vivo des temps de relaxation tissulaires." Toulouse 3, 1997. http://www.theses.fr/1997TOU30094.
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Dans le but d'obtenir une quantification objective des parametres relaxometriques qui sont a l'origine du contraste de l'image en irm, nous avons developpe une methode de mesure rapide et precise des temps de relaxation longitudinale, t#1, et transversale, t#2, des protons de l'eau tissulaire. Sa mise en oeuvre n'impose pas de modifier les protocoles usuels d'imagerie ce qui permet d'effectuer une analyse quantitative des images d'irm lors d'examens de routine. Les temps de relaxation t#1 et t#2 sont obtenus respectivement a partir de l'acquisition d'images d'echos de gradient de type f. L. A. S. H. , rrealisees avec differentes valeurs de l'angle d'impulsion, et d'echos de spins a nombre limite d'echos. Les durees d'acquisition necessaires a l'obtention de ces parametres sont, pour des images de matrice 128#2, de l'ordre de 15 secondes pour t#1 et 30 secondes pour t#2. Une determination precise de la variation de la densite de proton n(h) entre deux elements d'image est egalement proposee. Elle utilise des sequences d'echos de gradient de temps d'echocs differents. La methode est validee sur fantomes (eurospin to-5 ; echantillons de solutions aqueuses de chlorure de manganese deuterees). L'ecart observe sur t#1, t#2 et n(h) entre les valeurs mesurees sur l'imageur et les valeurs spectrometriques de reference, est de l'ordre de 5%. Les valeurs de t#1 et t#2 obtenues in vivo pour differents tissus sont en bon accord avec celles publiees dans la litterature ce qui permet d'envisager une caracterisation tissulaire standardisee et reproductible basee sur la determination des parametres relaxometriques tissulaires.
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Canonge, Rafael. "Imagerie moléculaire 3D quantitative des tissus en utilisant la microscopie Raman cohérente sans marquage." Thesis, Ecole centrale de Marseille, 2017. http://www.theses.fr/2017ECDM0010/document.
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Cette thèse porte sur l'utilisation et le développement de techniques de microscopie multiphotonique pour l'imagerie d'échantillons biologiques humains. Une plateforme d'imagerie multiphotonique utilisant les contrastes non linéaires sans marquage tels que la fluorescence à deux photons, la génération de seconde harmonique, et les mécanismes Raman cohérent (CARS et SRS) a été conçue et développée au cours de cette thèse, et les travaux expérimentaux suivant deux axes de recherche principaux sont présentés.Dans une première partie , l'imagerie tridimensionnelle et sans marquage des muqueuses du système digestif humain est comparée aux images histologiques classiques avec marquages colorimétriques. Nous montrons que les techniques multiphotoniques utilisées permettent de reconstituer la structure et de discerner les différents éléments moléculaires présents dans les tissus dans le but d'obtenir une caractérisation des zones touchées par le développement de tumeurs cancéreusesThis thesis focuses on multiphotonic microscopy techniques development and use in order to image human biological samples. A multiphotonic imaging setup using label-free nonlinear contrasts mechanisms such as two-photons fluorescence, second harmonic generation, or stimulated Raman effect (CARS or SRS) has been designed and developped during this PhD, and I present the experimental work in two main research topics.In a first part, we compare label-free 3D imaging with classic histological imaging using colorimetric labels in human digestive system. We show that multiphotonic technics allow to reconstruct the organization and discern the molecular compounds inside the tissues, in order to get a caratérization of the cancerous tumors developpement.The second part is related to the application of our multimodal setup to the quantitative study of real active molecular compounds real time penetration into in vivo human skin. We show that multiphotonic microscopy make possible to mesure active molecules in depth 3D concentration in the skin in order to understand transcutaneous diffusion mechanisms in cosmetic and pharmacological applications
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Julliard, A. Karyn. "Tissu glio-interstitiel et régulation calcique des espaces extracellulaires dans le muscle rétracteur du byssus de Mytilus : étude morphométrique et microanalyse quantitative de compartiments calciques subcellulaires." Lyon 1, 1986. http://www.theses.fr/1986LYO10078.
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Faure-Brac, Mathieu. "Effects of thermophysiology on the evolution of Pseudosuchia (Archosauria) : contributions of paleohistology and isotopic geochemistry using phylogenetic comparative methods." Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS233.
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Il est aujourd’hui communément admis que les archosaures sont ancestralement endothermes, soit qu’ils présentent des mécanismes de thermogenèse non frissonnante. Parmi les archosaures, les crocodiliens actuels sont pourtant des ectothermes, mais présentent des caractéristiques anatomiques et moléculaires traditionnellement associées à l’endothermie : un cœur à quatre cavité ; plusieurs acquisitions liées à une respiration efficace, comme un muscle diaphragmatique et un flux d’air unidirectionnel ; la formation de tissus osseux liés à des taux de croissance élevés ; un taux d’évolution mitochondrial important. Des études sur des pseudosuchiens éteints ont conclus que la plupart des espèces du Trias étaient endothermes. La perte de l’endothermie au sein du clade doit cependant toujours être définie. Durant cette thèse, j’ai utilisé la géochimie des isotopes stables et l’ostéohistologie quantitative pour inférer la température corporelle et le taux métabolique au repos, deux proxies de l’endothermie, de plusieurs métasuchiens. J’ai conclus que le clade Metasuchia était ancestralement ectotherme et, à l’aide d’une reconstruction ancestrale des caractères, que l’endothermie a probablement été perdue au nœud Crocodylomorpha. J’en déduit l’hypothèse suivante : l’endothermie des pseudosuchiens était probablement à un stade plus primitif que celle des dinosaures. Contrairement à ces derniers, les pseudosuchiens endothermes n’ont pu survivre à l’extinction de masse de la fin du Trias, ne laissant pour seul survivant que les crocodylomorphes ectothermesIt is today well established that archosaurs are ancestrally endotherms, i.e., they present mechanisms of non shivering thermogenesis. Among archosaurs, extant crocodilians are ectothermic but present particular anatomical and molecular features traditionally associated with endothermy: a fourc hambered heart; several acquisitions linked to an efficient breath such as a diaphragmatic muscle and unidirectional airflow; the deposition of high growth rate bone tissues; a high mitochondrial rate of evolution. Studies on extinct pseudosuchians suggested that most of the Triassic species were endothermic, but the timing of the loss o fendothermy in Pseudosuchia still has to be constrained both temporally and phylogenetically.In this thesis, I use stable isotopic geochemistry and quantitative osteohistology to infer the body temperature and the resting metabolic rate, to proxies to infer endothermy, of several metasuchians. I concluded that metasuchians are primitively ectothermic, and inferred the loss of endothermy at the node Crocodylomorpha using ancestral state reconstruction. I hypothesize pseudosuchian’s endothermy was in a more primitive state than dinosaurs’ and that they were not able to survive the end Triassic mass extinction. The only surviving pseudosuchians were then ectothermic crocodylomorphs, leading to extant species
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Elschner, Cindy. "Analyse der knöchernen Einheilung von Biomaterialien mit der Magnetresonanztomographie." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-204714.
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Die Analyse von Implantat-Gewebe-Wechselwirkungen basiert derzeit hauptsächlich auf histologischen Techniken. Der invasive Charakter der histologischen Präparation lässt allerdings keine Untersuchung am lebenden Tier zu. Dadurch ist es nicht möglich, den Prozess der Implantateinheilung wiederholt an einem Tier zu beobachten. Die Folgen sind eine hohe Anzahl aufzuwendender Versuchstiere und eine Vergrößerung der Messunsicherheit infolge der gestiegenen biologischen Variabilität. Nicht-invasive, bildgebende Verfahren spielen daher eine zunehmende Rolle für die Entwicklung neuer Biomaterialien. Während die Computertomographie (CT) häufig zur Untersuchung der knöchernen Implantateinheilung verwendet wird, hat sich die Nutzung der Magnetresonanztomographie (MRT) für diese Fragestellungen bisher nicht etabliert. Bei der Magnetresonanztomographie handelt es sich, analog zur Computertomographie, um ein bildgebendes Verfahren zur nicht-invasiven Erzeugung digitaler Schnittbilder. Im Gegensatz zur CT, die das Hartgewebe abbildet, wird bei der MRT das Weichgewebe detektiert, wobei keine ionisierende Strahlung verwendet wird. Der große Vorteil der MRT gegenüber anderen bildgebenden Methoden besteht darin, dass es möglich ist, das Weichgewebe auf den Schnittbildern anhand verschiedener Kontraste darzustellen. Zusätzlich können MR-spezifische Parameter quantifiziert werden, die einen direkten Rückschluss auf die Struktur zulassen. Mit diesen Kennzahlen ist es möglich, Veränderungen im Weichgewebe analysieren. Das Ziel der Arbeit war es deshalb, die Eignung und mögliche Anwendungen der Magnetresonanzto-mographie (MRT) zur Analyse der Implantat-Gewebe-Wechselwirkungen zu erörtern. Für die Untersu-chungen wurde ein NMR-Spektrometer inklusive Imaging-Zubehör verwendet. Die Dissertationsarbeit beinhaltete sowohl die Untersuchung verschiedener Materialsysteme hinsichtlich ihrer Eignung für die MRT und deren Biokompatibilität, als auch die Analyse der knöchernen Einheilung ausgewählter Biomaterialien. Diese umfasste Aussagen zur Darstellbarkeit und Abgrenzbarkeit von Strukturen und beinhaltete auch quantitativ gewonnene Messparameter. Die Ergebnisse wurden stets im Vergleich mit der Histologie diskutiert. In der Arbeit konnte dargestellt werden, dass die Überprüfung der Eignung des zu untersuchenden Materials für die MRT vor der Analytik erfolgen muss. Es wurde demonstriert, dass Metalle erheblich mit dem MR-System wechselwirken können, was in der Konsequenz zu drastischen Störungen der Bildqualität führt. Diese Effekte waren stark von den ausgewählten Messparametern abhängig. Als ein MRT-geeignetes Verbundmaterial wurde Titan-beschichtetes Polyetheretherketon (PEEK/Ti) vorgeschlagen. Die Beschichtung mit Titan führte zu einer signifikant verbesserten Biokompatibilität des Kunststoffes. Die erfolgreiche Analyse der knöchernen Einheilung mit der Magnetresonanztomographie wurde im Rahmen von zwei tierexperimentellen Studien an verschiedenen Biomaterialien gezeigt (die Analyse erfolg-te ex vivo). Die Untersuchung der knöchernen Integration eines Zahnimplantates aus PEEK/Ti hatte das Ziel, die Darstellbarkeit des Implantates und knöcherner Strukturen mit der Magnetresonanztomographie zu evaluieren. Außerdem wurde ebenfalls gezeigt, dass es anhand der MRT-Schnittbilder möglich ist, quantitative Messgrößen zur Beschreibung des Einheilprozesses zu gewinnen. Aufgrund der geringen Versuchstierzahl wurde jedoch eine breite Streuung der Messdaten festgestellt. Allerdings besitzt die Studie durch die Untersuchung eines Zahnimplantates aus Polyetheretherketon/Titan mit der MRT nicht nur Neuheitswert in der Biomaterialforschung, sondern schlägt gleichzeitig eine Brücke zur klinischen, dentalen Implantologie. Die Bewertung der Darstellbarkeit knöcherner Strukturen und der verwendeten (teils tissue-engineerten) Knochenersatzmaterialien mit MRT und Histologie und des klinischen Erfolges derselben bildeten einen Schwerpunkt der zweiten tierexperimentellen Studie (die Analyse erfolgte ex vivo). Es war möglich, mit beiden bildgebenden Verfahren zu zeigen, dass sich die verwendeten Knochenersatzmaterialien nicht für die vorgesehene Anwendung eigneten. Die Beurteilung der Übereinstimmung der quantitativ gewonnenen Parameter beider Analysenmethoden bildete den Abschluss der Arbeit. Es wurde festgestellt, dass zwischen den Messdaten stets ein syste-matischer Unterschied bestand. Nachweislich war dieser aber weniger das Resultat der ungleichen lateralen Auflösungen oder der unterschiedlichen Darstellbarkeit von Gewebestrukturen der beiden Verfahren, sondern konnte auf den Einfluss der Analyse verschiedener Schichtebenen und individueller Unterschiede bei der digitalen Quantifizierung der auswertenden Personen zurückgeführt werdenCurrently, histological techniques are used to analyse implant-tissue-interactions. However, these methods are destructive and do not allow for the investigation of living animals. Therefore, it is not possible to study the integration of biomaterials repeatedly with one animal, resulting in a large number of animals and an increase of biological variability. Non-invasive imaging techniques have gained interest in the field of biomaterials. Whereas Computed Tomography (CT) was often used to evaluate the osseous integration, the assessment using Magnetic Resonance Imaging (MRI) has not been established, yet. MRI is a non-invasive medical imaging method that detects soft tissue. In contrast to CT the method does not require individuals to be exposed to radiation. The most important benefit of MRI is the possibility to acquire different soft tissue contrasts in situ because the various tissues have different signal intensities on MR images that can be altered by using different experimental parameters. Furthermore, it is possible to gain MR-specific properties that allow conclusions to the tissue structure. Thus, the objective of the doctoral thesis has been to investigate the suitability of MRI for the use in biometerial research and to show potential areas of application. The examinations were performed using a laboratory NMR-spectrometer inclusive imaging accessory. The thesis included an evaluation of the MR compatibility of different materials and their biocompati-bility and an analysis of the ingrowth of chosen biomaterials into bone. For that, the detection and identification of tissue structures and biomaterials was investigated with both, MRI and histology. Additionally, quantitative parameters were acquired and their comparability was assessed. It was clearly demonstrated, that metals interacted with the MR system and provoked large image distortions. These effects were strongly dependent on experimental parameters chosen. Polyetheretherketone with titanium coating (PEEK/Ti) was investigated and has been found to be MR safe. Above all, it was demonstrated that the biocompatibility of the polymer was significantly enhanced by coating with titanium. Within two animal studies the successful analysis of the osseous healing of different biomaterials with MRI was presented. To demonstrate the visibility of bony structures and biomaterials a dental implant made of PEEK/Ti was analysed. The ability to measure quantitative data in analogy to histomorphometry was shown, ditto. A large variation of the values was detected due to the limited number of animals used for the pilot study. Evaluating the displayability of bone and (to some extent tissue engineered) bone substitutes and assessing the clinical success of these materials was one main focus of the second animal study. Both, MRI and histological analysis could undeniably illustrate that all of the bone substitutes were not suitable for the chosen application. The thesis was completed with the determination of the agreement of quantitative values from both analysing methods. It was concluded that all values gained from the animal study were significantly different. It was proven that the chosen slice position and the image interpretation with two evaluators had a larger share to disagreement than the different lateral resolution of MRI and histological images or the diverging displayability of bone and bone substitutes. By investigating a MR suitable dental PEEK implant the doctoral thesis fulfils the criteria of novelty in biomaterial research. Moreover, it forges links between preclinical research and dental implantology
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Chamming's, Foucauld. "Elastographie quantitative des tumeurs du sein et de la réponse au traitement." Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015USPCB152/document.
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Introduction : L’élastographie shear wave (ESW) est une technique récente d’échographie qui évalue quantitativement la dureté des tissus et permet d’améliorer la caractérisation des lésions mammaires. Comme toute nouvelle technique d’imagerie, l’ESW nécessite une validation préclinique pour définir les conditions d’utilisations et établir les limites des champs d’applications dans lesquelles la technique pourra être considérée comme valide. Matériels et méthodes : Dans une première partie effectuée au laboratoire de recherche en Imagerie nous avons étudié les éléments histologiques sous tendant l’image d’ESW sur un modèle de cancer du sein implanté chez la souris, au cours de sa croissance puis sous traitement. Dans une deuxième partie, nous avons étudié chez des patientes le rôle de la compression manuelle en ESW pour la caractérisation des lésions mammaires. Dans une dernière partie, effectuée en collaboration avec une équipe de l’Institut Langevin Ondes et Images, nous avons étudié la faisabilité d’un nouveau paramètre, le module de cisaillement non linéaire pour l’analyse des lésions mammaires. Résultats : Au laboratoire, nous avons établi des corrélations entre la dureté mesurée en élastographie et les caractéristiques histologiques des tumeurs, y compris sous traitement. Nous avons montré que la fibrose était associée à une dureté élevée et la nécrose à une dureté moindre. Notre étude clinique a montré qu’une compression manuelle minimale était nécessaire pour obtenir de bonnes performances de l’ESW et qu’une pression trop élevée devait être évitée. Enfin nous avons montré la faisabilité en imagerie mammaire d’un nouveau paramètre quantitatif obtenu en élastographie shear wave : le module de cisaillement non linéaire. Conclusion : A partir de travail de thèse, une meilleure compréhension de la part des éléments biologiques et techniques en ESW du sein est possible et des recommandations pour l’utilisation clinique peuvent être formulées. Nos observations cliniques ont entrainé la mise au point d’un nouveau paramètre diagnostique quantitatif : le module de cisaillement non linéaireIntroduction: Shear Wave Elastography (SWE) is a recent ultrasound technique assessing quantitatively tissue stiffness and improving breast lesions characterization. As every new imaging technique, SWE requires a pre clinical validation in order to define in which conditions it should be used and precise the applications for which the technique is validated. Materials and methods: First, in a research lab we have investigated the pathological features underlying SWE image in a breast cancer model implanted in mice, during tumor growth and under therapy. Secondly, we have studied in patients the role of manual compression in SWE for the characterization of breast lesions. Finally, in collaboration with on team from Institut Langevin Ondes et Images, we have studied the feasibility of a new parameter, the non-linear modulus, for breast lesion assessment. Results: in the research lab, we have shown correlations between stiffness as measured with SWE and pathological features of tumors, even on treatment. We have shown that fibrosis was associated with high stiffness values and necrosis with lowers. Our clinical study, showed that a minimal manual compression was required for optimal performance of SWE and that strong compression should be avoided. Finally, we demonstrated feasibility of a new parameter, derived from SWE, the non-linear modulus. Conclusion: Our work provides a better understanding of biological and technical elements of SWE. On the basis of our results, new recommendations may be made for the use of SWE in clinical practice. From our clinical findings, we developed a new quantitative parameter, which may be useful for the diagnosis of breast lesions, the non-linear modulus
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Binet, Aurélien. "Analyse qualitative et quantitative du remodelage vasculaire utérin sur deux modèles murins d'insuffisance placentaire : modèle hyperthermie et modèle anémie ferriprive." Thesis, Tours, 2012. http://www.theses.fr/2012TOUR3301.
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Le retard de croissance intra-utérin par altérations vasculaires placentaires affecte 4% des grossesses actuelles. Ses mécanismes d’installation encore inconnus ont un impact pédiatrique important responsable d’une mortalité non négligeable. La combinaison d’un retard de croissance intra-utérin et de modifications vasculaires placentaires sur un modèle animal est nécessaire pour comprendre ces mécanismes et envisager une étude thérapeutique ultérieure. Le but de ce projet est de mettre au point dans un premier temps un modèle animal qui associe au retard de croissance intra-utérin les modifications vasculaires placentaires retrouvées dans la physiopathologie humaine. Pour cela, deux modèles animaux murins ont été étudiés : l'hyperthermie en fin de gestation et l’anémie par carence martiale pré et péri-gestationnelle. Une étude qualitative et quantitative par échographie (échographie Doppler et échographie de contraste) associée à une étude anatomopathologique. immuno-histochimiques et spectroscopique des placentas a été réalisée. L’optimisation du modèle animal définitif a requis dans un premier temps la mise au point de repères anatomiques inexistants à l'heure actuelle permettant la reproductivité des mesures échographiques ainsi que la mise en évidence de l’innocuité du produit de contraste échographique utilisé. Une étude placentaire globale nous a permis d’enregistrer des modifications structurelles liées au modèle analysé. L’étude de ces deux modèles animaux nous a permis d’établir un protocole de mesure standardisé et de mettre en évidence l’absence d’effet de l’utilisation du produit de contraste échographique sur la gestation. L’hyperthermie tout comme la carence martiale sont responsables d'un retard de croissance intra-utérin avec un effet dose dépendant. Les modifications vasculaires placentaires retrouvées dans le modèle hyperthermie à type d'ischémie-hémorragique n’apparaissent pas consécutives à des modifications vasculaires installées mais séquellaires de cet incident aigu. Les modifications hémodynamiques enregistrées dans le cadre de la carence martiale sont plutôt en faveur de modifications vasculaires en accord avec la pathologie humaine. L’étude spectroscopique ne met pas en évidence de changement métabolomique particulier. Ces deux modèles permettent donc l’installation d’un retard de croissance intra-utérin corrélé positivement à l’intensité du protocole. Le modèle anémie tend à se rapprocher au mieux de la pathologie humaine ; son étude reste à approfondir sur des effectifs plus conséquentsThe intra-uterin growth restriction by placental vascular modifications affects 4% of the current pregnancies. lt’s still unknown installation mechanism has an important pediatric impact with a significant mortality. The association of intra-uterin growth restriction and placental vascular defects on an animal model is necessary to understand this mechanism and envisage a therapeutic study later. The aim of Ibis project is to establish at first an animal model which associates intra-uterin growth restriction and vascular placental modifications found in the human physiopathology For that purpose, two murine models were studied : hyperthermia at the end of the gestation and anaemia by iron deficiency before and during the gestation. A qualitative and quantitative study by ultrasonography (Doppler ultrasonography and contrast ultrasonography) associated with anatomopathological, immune-histochemical and spectroscopic studies of the placentas was realized. The optimization of the definitive animal model required at first anatomical marks development, allowing reproduction of the ultrasonographic measures as well as revelation of the ultrasound contrast product harmlessness. A global placental study allowed us to note structural modifications connected to the analyzed model. The study of these two animals models allowed us to establish a standard measuring protocol and show that ultrasonographic contrast product use had no effect on the gestation. The hyperthermia, as the iron deficiency, is responsible of an intra-uterin growth restriction with a positive effect dose related. The vascular placental modifications found in the hyperthermia model as hemorrhage and ischaemia areas do not appear as the result of vascular modifications but after-effects of this acute incident. The hemodynamical modifications registered within the framework of the iron deficiency are rather in favour of vascular modifications in agreement with the human pathology. The spectroscopic study does not show metabolomic modifications. These two models allow the installation of an intra-uterin growth restriction positively correlated with the protocol intensity. The anaemia model gets closer to the human pathology; its study remains b he continued with more consequent numbers
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Mony, Marie-Cécile. "Étude des cartographies chimiques élémentaires et des concentrations relatives des cations du tissu cardiaque en microscopie ionique analytique : aspects physiologiques et pharmacologiques." Paris 11, 1989. http://www.theses.fr/1989PA112313.
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L'étude des distributions des cations (Na, K, Ca, Mg) du tissu cardiaque est abordée, du fait de développements technologiques récents, et compte tenu du rôle important de ces ions dans le maintien des propriétés structurales et fonctionnelles du tissu. La microscopie ionique utilisant les phénomènes d'émission ionique secondaire permet d'obtenir successivement les cartographies chimiques de ces éléments, avec une résolution latérale de l'ordre d'1 micron. Afin de limiter les redistributions et la fuite de ces ions diffusibles, une méthode de préparation des échantillons par congélation est nécessaire. Cette étude est une approche critique des possibilités et des limites des méthodes de cryofixation et cryosubstitution à l'étude des ions diffusibles. Dans ce travail, les localisations physiologiques du Na, K, Ca, Mg ont été étudiées et comparées aux distributions obtenues après fixation chimique. L'adéquation de la méthode de préparation a ainsi été démontrée, de même que par l’étude du lithium, après traitement à dose pharmacologique. Une méthode d'analyse semi-quantitative permet d'observer ses effets sur les concentrations relatives des cations. La spécificité de la localisation membranaire du calcium a été vérifiée par l'utilisation du lanthane et tant que marqueur extra cellulaire, et par la superposition de son image, à celle du calcium, à l'aide d'un traitement d'images. De même, ses effets sur les cations intracellulaires ont été observés. Les modifications des compartiments cellulaires et membranaires du calcium ont été visualisées et quantifiées sous l'effet de l'adrénaline et du baryum.
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Bastard, Cécile Morgane. "Elastographie impulsionnelle quantitative : caractérisation des propriétés viscoélastiques des tissus et application à la mesure de contact." Thesis, Tours, 2009. http://www.theses.fr/2009TOUR3130.
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L'élastographie impulsionnelle est une technique de caractérisation tissulaire permettant de mesurer in vivo les propriétés viscoélastiques des tissus vivants en étudiant la propagation d'ondes de cisaillement. Au cours de cette thèse, un outil numérique permettant de simuler des ondes de cisaillement dans des tissus mous viscoélastiques a été développé et validé par comparaison avec un modèle analytique et des données expérimentales. Dans un deuxième temps cet outil de simulation a été utilisé pour étudier dfférentes stratégies permettant de mesurer l'élasticité de milieux hétérogènes. Plusieurs méthodes permettant de mesurer in vivo la viscosité de cisaillement des tissus vivants ont également été étudiées. Ces différentes techniques ont notamment été appliquées à l'étude des propriétés visocélastiques du foie par élastographie impulsionnelle quantative. Enfin, un nouveau système de micro-élastographie permettant de mesurer les paramètres visocélastiques de petis organes ou de tissus situés au contact de la sonde a été proposé. Ce système de micro-élastographie de contact a été appliqué avec succès pour mesurer in vivo l'élasticité du foie sur deux modèles murins : un modèle d'amyloïdose et un modèle de fibrose expérimentaleTranscient elastography is a tissue characterization technique used to measure non-invasively the viscoelastic properties of human tissues. In hepatology, this new technique is now a common diagnostic toll to assess liver fibrosis. However, it could still benefit from technological and algorithmic improvements to extend its use to order clinical applications. In this thesis, a numerical tool to simulate shear wave propagation in viscoelastic soft tissues was developed. Its results were validated by comparison with those provided by an analytical model and compared to experimental data. This tool was then used to test several inverse methods to compute the shear modulus and the shear viscosity of a medium from the displacements measured using ultrasound. These techniques were applied in vivo to measure the viscoelastic properties of liver. Finally, a novel micro-elastography device dedicated to the measurement of the elasticity of small organs or tissues was introduced and tested to quantify the elasticity of the liver in two murine mdols in vivo : a model of amyloidosis and a model of experimental fibrosis
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Saade, Ricardo Destro. "Punção aspirativa percutanea do epididimo (PESA) : estudo quantitativo, histologico e estereologico em ratos." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/308532.
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Orientadores: Carlos Arturo Levi D'Ancona, Paulo Augusto NevesTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
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Resumo: Introdução: O tratamento da infertilidade masculina tem evoluído muito nas últimas décadas. O advento de técnicas de reprodução assistida (RA) e, particularmente, a injeção intracitoplasmática de espermatozóides (ICSI) tornaram possível o tratamento de indivíduos até então considerados inférteis, como os casos de azoospermia obstrutiva e os de azoospermia não obstrutiva. Nestes casos, na impossibilidade de correção cirúrgica, outros procedimentos de obtenção de espermatozóides podem ser realizados como a aspiração microcirúrgica dos epidídimos (MESA), punção aspirativa percutânea dos epidídimos (PESA), aspiração testicular de espermatozóides (TESA) ou a extração testicular (TESE). Objetivos: A proposta de trabalho foi verificar a obtenção de espermatozóides viáveis em até cinco punções percutâneas do epidídimo. Analisar as alterações histológicas inflamatórias e cicatriciais, assim como a densidade de fibras de músculo liso e colágenas nos epidídimos de ratos, após punções. Material e método: O grupo piloto consistiu em quatro animais, sendo dois para estudo da anatomia e da histologia do epidídimo normal e outros dois para avaliação dos efeitos da vasectomia. A vasectomia bilateral foi realizada por meio de laparotomia infra-umbilical. Foi padronizado o lado direito para estudo e o esquerdo como controle. O grupo estudado consistiu em 50 ratos que realizaram vasectomia e foram separados em cinco grupos de I a V, contendo 10 animais cada. Os animais do grupo I foram submetidos a uma punção percutânea trans-escrotal; II a duas punções; III a três punções; IV a quatro punções; V a cinco punções. As punções dos epidídimos foram feitas após 30 dias da vasectomia, com escalpe 25G na cabeça do epidídimo. O material extraído foi suspenso em meio de cultura HTF e analisado em câmara de Makler. O intervalo entre cada punção foi de 15 dias e os animais foram sacrificados após 15 dias da última punção. Os epidídimos foram fixados em líquido de Bouin. Foram realizados estudos histológicos e estereológicos dos epidídimos puncionados. Resultados: O número médio de espermatozóides recuperados nas punções foi de: 48,78 x 106 /ml, 37,55 x 106 /ml, 26,33 x 106 /ml, 33,90 x 106 /ml e 41,34 x 106 /ml, nos grupos I a V, respectivamente. Após a análise histológica, observou-se que as variáveis infiltrado linfoplasmocitário, reação granulomatosa, fibrose e desarranjo estrutural apresentaram diferença significativa a partir da segunda punção. O efeito cumulativo das punções somente foi observado nas variáveis infiltrado linfoplasmocitário e fibrose, mostrando que existe diferença significativa entre os grupos I e II em relação aos grupos III, IV e V. No estudo estereológico, a densidade volumétrica do tecido conjuntivo foi de 21,56%, 27,60%, 35,67%, 37,56% e 38,60% no lado puncionado nos grupos I a V (p<0,05). Conclusões: No presente estudo, verificamos a obtenção de espermatozóides em todos os grupos até cinco punções. Todos os animais apresentaram alterações histológicas significativas dos epidídimos, quando comparados ao grupo controle, a partir da segunda punção, exceto na variável necrose. Somente nas variáveis infiltrado linfoplasmocitário e fibrose foram observadas efeito cumulativo das PESA. O estudo estereológico demonstrou aumento da densidade volume do tecido conjuntivo dos epidídimos provocado pelas punções
Abstract: Introduction: The treatment of male infertility had a great development in the last decades. The advent of assist reproductive techniques and specially the intra-cytoplasmic sperm injection (ICSI) has allowed the treatment of these patients otherwise considered infertile. Patients with obstructive and non-obstructive azoospermia, whose surgical reconstruction is not possible, can be submitted to retrieval spermatozoa procedures including microsurgical epididymal sperm aspiration (MESA), percutaneous epididymal sperm aspiration (PESA) testicular sperm extraction (TESE) and testicular sperm aspiration (TESA). Objectives: To verify the retrieval of viable spermatozoa within up to five percutaneous epididymal sperm aspirations and to evaluate the histological and stereological modifications in the rat epididymis after the procedures. Material and Methods: The pilot group consisted of four animals, two of them were used in the study about anatomy and histology of normal epididymis. The other two were used to verify the effects of the vasectomy. These procedures were performed through infra-umbilical laparotomy. The right side was standardized for the study group and the left for control. A total of 50 Wistar rats underwent vasectomy procedures and were distributed into five groups I to V, totalizing 10 animals each. In the group I, the animals underwent to one PESA procedure, II two, III three, IV four and V five. The epididymal punctures were done with 25G scalp in the caput after 30 days of the vasectomy and consecutively after 15 days of the previous puncture. The material extracted was suspended in HTF solution culture and analyzed in a Makler chamber. The epididymis were fixed in Bouin technique. Histological and stereological analyses were performed in the punctured epididymidis. Results: The number of retrieved spermatozoa was: mean 48.78 x 106 /ml, 37.55 x 106 /ml, 26.33 x 106 /ml, 33.90 x 106 /ml e 41.34 x 106 /ml, from group I to V. The histological analyses included evaluation of infiltration of lymphocytes and plasmocytes, granulomatous reaction, fibrosis and structural disorder; these alterations presented significant differences after the second puncture. The cumulative effect was observed only within the variables: lymphocytic and plasmocytic infiltrate and fibrosis. It was found differences in the groups I and II in comparison with III, IV and V. The stereological analyzes showed significant increase in connective tissue volume 21.56%, 27.60%, 35.67%, 37.56% and 38.60% from group I through V. Conclusions: In this study, it was performed retrieval of spermatozoa in all groups up to five punctures. All the animals presented histological alterations in the epididymis after the second puncture when compared to the control group, except necrosis, and only lymphocytic and plasmocytic infiltrate and fibrosis were shown as cumulative effects within the punctures. The stereological analyses showed increase of connective tissue volume that was caused by the punctures
Doutorado
Cirurgia
Doutor em Cirurgia
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Amstalden, Eliane Maria Ingrid 1957. "Alterações histopatologicas da pele na esclerose sistemica : estudo quantitativo e qualificativo." [s.n.], 1992. http://repositorio.unicamp.br/jspui/handle/REPOSIP/312787.
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Orientador : Athanase BillisTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
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Resumo: A avaliação das alterações cutâneas na Esclerose Sistêmica (ES) é de fundamental importância, uma vez que a pele é considerada o grande elemento diagnóstico e o órgão mais frequentemente envolvido nesta moléstia. Existem divergências em relação aos achados histopatológicos nos vários níveis da pele, bem como são raros os estudos quantitativos na abordagem e avaliação dessas alterações. Este estudo se baseou na avaliação comparativa da pele de doentes com ES e controles, no que se refere aos seguintes aspectos histopato16gicos: a avaliação da epiderme quanto à atrofia, retificação e distúrbio de pigmentação melânica; a análise da derme e hipoderme quanto à proliferação de fibras colágenas; atrofia de anexos; alterações de vasos; e a presença de infiltrado inflamatório. Observou-se também a correlação dos principais achados histopatológicos entre si e em relação a parâmetros clínicos como a idade, o peso, tempo de doença forma e estadiamento clínicos. Foram avaliados 48 doentes e 16 controles. As amostras foram obtidas através de biópsia de pele da face dorsal da terceira falange proximal direita. Os cortes histológicos foram examinados através de métodos quantitativo e qualitativo e os resultados encontrados foram submetidos a estudo estatístico.
Abstract: The evaluation of cutaneous changes in Systemic Sclerosis (SSc) 1s very important, because the skin is considered fundamental for the diagnosis and it is the organ more frequently involved in this disease. There are many disagreements about the histopathologic features in the various levels of the skin, and there are scarce quantitative studies evaluating these alterations. This study based on the comparative evaluation of the skin of patients with SSc and controls, considers the following histopathologic features: the appraisal of the epidermis concerning the atrophy, retification and melanin pigmentary disturbance; the analysis of the dermis and subcutaneous concerning the fibers and atrophy of the cutaneous appendages; vascular abnormalities and the presence of inflammatory infiltrates. The relationship between the main histopathologic features themselves and in relation to the clinical parameters like age, weight, duration of the disease, clinical form classification and clinical stage, were studied. Forty eight patients with SSc and sixteen controls were analysed. The skin samples were obtained by biopsies of the dorsal face of the right third proximal phalange. The microscopic study was done by quantitative and qualitative methods and the results were submitted to statistic study.
Doutorado
Anatomia Patologica
Doutor em Ciências Médicas
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Meira, Kássia Regina Simões. "Estudo quantitativo da permeabilidade de lesões cariosas naturais de esmalte à solução de Thoulet." Universidade Federal da Paraíba, 2014. http://tede.biblioteca.ufpb.br:8080/handle/tede/6664.
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Previous issue date: 2014-02-27Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
In natural enamel caries, remineralization and resin infiltration are directly dependent on the permeability of the enamel to the agents that promote them. Due to its low permeability, the surface layer of carious lesions has been considered, a natural barrier for penetration of such agents. In this study we provide, for the first time, quantitative volumetric data on the infiltration of a test solution (aqueous solution of mercuric and potassium iodide: Thoulet s solutions) in the surface layer of natural enamel caries and confirmed our hypothesis that the ratio of the squared water volume by pore volume (αd) is, among all major component volumes (mineral, organic, total water and loosely bound water), the best predictor of the proportion of the pore volume infiltrated by the tested solutions. The predictive value of αd was higher for Thoulet s solution with refractive index 1.47 (R2 = 0.505) compared to Thoulet s solution with refractive index 1.40 (R2=0.435). Real-time 2D mapping of infiltration revealed that penetration of the solution started on the original enamel surface, followed the prism paths towards the bottom of the body of the lesion, and caused air flow in the opposite direction. Infiltration was negligible through the pores at the surfaces exposed by cutting and grinding. Data on effective pore volume, pore viscosity and from fluid flow mechanics provided new information on the nature of the infiltration of materials in the surface layer of natural enamel caries. Our results might provide a deeper insight into the transport of agents used to promote remineralization and resin infiltration in natural enamel caries.
Em lesões cariosas naturais de esmalte, os agentes terapêuticos que promovem a remineralização e infiltração do esmalte desmineralizado por resina dependem diretamente da permeabilidade do tecido. A camada superficial tem sido considerada uma barreira para penetração desses agentes devido à sua baixa permeabilidade. Neste estudo, pela primeira vez, são fornecidos dados volumétricos quantitativos sobre a infiltração de uma solução teste (solução aquosa de iodeto de mercúrio e de potássio - Solução de Thoulet) na camada superficial da lesão cariosa natural de esmalte. Confirmou-se a hipótese de que a razão do volume de água ao quadrado dividido pelo volume de poros (αd) é dentre todos os volumes (mineral, orgânico, água total e água fracamente aderida), o melhor preditor da proporção do volume de poros infiltrados pelas soluções testadas. O valor preditivo de αd foi maior pra Solução de Thoulet com índice de refração 1,47 (R2= 0,505) em comparação à Solução de Thoulet com índice de refração 1,40 (R2= 0,435). O mapeamento em 2D da infiltração em tempo real revelou que a penetração da solução começou inicialmente através da superfície do esmalte, seguindo para o interior do corpo da lesão seguindo a trajetória dos prismas e provocando um fluxo de ar no sentido oposto. A infiltração foi insignificante através dos poros nas superfícies expostas por desgaste. Dados sobre os volumes efetivos, viscosidade e da mecânica do fluxo de fluidos nos poros, forneceram informações nunca antes publicadas sobre a natureza da infiltração de materiais na camada superficial e lesão cariosa natural de esmalte. O presente estudo pode fornecer uma visão mais profunda sobre o transporte de agentes usados para a remineralização e infiltração de resinas na lesão cariosa natural de esmalte.
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Legendre, Lucas. "Les crocodiles sont-ils devenus secondairement ectothermes ? : étude paléohistologique." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066307/document.
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Les archosaures sont un clade de vertébrés comprenant les oiseaux, les crocodiliens, ainsi que de nombreux groupes fossiles. Ce groupe fait depuis plusieurs décennies l'objet d'un important débat parmi les paléontologues quant à l'évolution du thermométabolisme au sein de ses différentes lignées. L'hypothèse classique considère que seuls les oiseaux modernes sont endothermes, tandis que tous les autres archosaures sont ectothermes. L'histologie osseuse permet d'étudier plusieurs traits relatifs au thermométabolisme impossibles à mesurer sur des spécimens fossiles ; c'est pourquoi nous avons utilisé des caractères mesurés sur des coupes histologiques d'os longs.Nous nous sommes consacrés dans une première partie à une revue détaillée de la mesure du signal phylogénétique pour des caractères ostéohistologiques dans deux clades de vertébrés, ce qui nous a permis de mieux définir l'approche à suivre dans la construction de nos modèles prédictifs.Après une étude préliminaire consacrée à l'élaboration d'un modèle prédictif du taux de croissance osseuse, nous avons construit un modèle global capable de prédire directement le taux métabolique de nos spécimens fossiles. Nos résultats montrent que la majorité des archosaures de notre échantillonnage étaient endothermes. Cela implique que le dernier ancêtre commun des archosaures était probablement endotherme, et que les crocodiliens sont donc devenus secondairement ectothermes, probablement en réponse aux contraintes du milieu aquatique. Des études plus spécifiques sur la lignée des pseudosuchiens devraient permettre de déterminer à quel niveau de l'arbre phylogénétique s'est effectué le retour à cet état ectothermeArchosaurs are a clade of vertebrates that includes birds, crocodiles, and numerous fossil groups. This clade has been a matter of debate among paleontologists for decades concerning the evolution of thermometabolism in its different lineages. The classical hypothesis considers that only modern birds are true endotherms, whereas all other archosaurs are ectotherms. Bone histology allows to study several traits linked to bone growth rate and thermometabolism, otherwise impossible to estimate on fossil specimens; for this reason, we used characters measured on long bone histological sections.In the first section, we extensively reviewed the measure of phylogenetic signal for osteohistological features in two clades of vertebrates, which was then used to define the methodology for building our predictive models.After a preliminary study during which we built a predictive model for bone growth rate, we built a global model to predict the metabolic rate of our fossil specimens, using both histological features and phylogenetic information for each specimen. Our results show that a majority of archosaurs in our sample were endotherms. This implies that the last common ancestor of archosaurs was likely an endotherm, and that modern crocodiles became secondarily ectothermic, probably in response to their aquatic environment. More specific studies on pseudosuchians should allow to precisely identify the level of the phylogenetic tree at which the ectothermic state was acquired, as well as adaptive constraints behind this acquisition
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Brito, Camila Santos de Mattos. "Análise quantitativa da infiltração de quinolina em lesões cariosas naturais proximais de esmalte." Universidade Federal da Paraíba, 2014. http://tede.biblioteca.ufpb.br:8080/handle/tede/6656.
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Immersion of natural enamel caries (NEC) in quinoline has been important for determining lesion size and mapping areas with different pore sizes, but quantitative volumetric data of the infiltration are not available. Here we provide first quantitative volumetric data of the volume infiltrated by quinoline (mostly < 50% of pore volume were infiltrated) in histological layers (including dark zone) of ground sections of NEC lesions (n = 20) and report that a parameter related to permeability predicted 60% of the variance of the volumetric infiltration. Distance from the original enamel surface was inversely related to the infiltrated volume. In most lesions the translucent zone was not the lesion front. Real-time 2D mapping of transport processes after immersion in quinoline revealed an early outward water flow and a late inward quinoline penetration, both following prisms paths parallel to the main axis of ground sections. New events of the nature of transport processes in ground sections of NEC lesions reported here can be explored to improve efficiency of both remineralizing agents and resin infiltrants for treatment of NEC.
A imersão em quinolina de lesões naturais de cárie em esmalte tem sido importante para determinar o tamanho da lesão e áreas com diferentes tamanhos de poros. No entanto, dados volumétricos quantitativos resultantes da infiltração desta substância não estão disponíveis na literatura. Sendo assim, o presente trabalho objetivou apresentar os primeiros dados quantitativos volumétricos do infiltrado por quinolina (na maioria das amostras < 50 % do volume de poros foram infiltrados) em camadas histológicas (incluindo zona escura) de cortes por desgaste de lesões cariosas naturais em esmalte (n = 20). Além disto, verificou-se que um parâmetro relacionado à permeabilidade previu 60 % da variância da infiltração volumétrica. A distância da superfície do esmalte original foi inversamente relacionada com o volume infiltrado. Na maioria das lesões, a zona translúcida não foi o front da lesão. Mapeamento em 2D em tempo real de processos de transporte após a imersão em quinolina, através de microscopia de luz polarizada, revelou primeiramente um fluxo de água para o exterior e uma conseguinte penetração por quinolina, ambos seguindo a trajetória dos prismas paralelamente ao eixo principal dos cortes por desgaste. Novos eventos da natureza dos processos de transporte em cortes por desgaste aqui relatados podem ser explorados para melhorar a eficiência de ambos os agentes remineralizantes e infiltrantes de resina para tratamento de lesões cariosas.
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Jetton, Emily Hope. "The development of processing methods for a quantitative histological investigation of rat hearts." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1216.
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In order to understand the mechanical functions of the cardiac muscle it is important to first understand the microstructure of the tissue. Young et al. (1998) realized that quantitative three-dimensional information about the ventricular myocardium is necessary to analyze myocardial mechanics. They developed a technique using confocal fluorescence laser scanning microscopy to obtain three-dimensional images. While this method worked well in rebuilding the myocardial tissue image by image, it was quite extensive and costly. Costa et al. (1999) developed a method that was used to perform three-dimensional reconstruction as well. Their method, while less expensive and much less time consuming, required sheet assumptions and did not look directly at the cross-fiber plane.
From Dr. Criscione's previous work on canines (Ashikaga et al., 2004), we found that the sheet structure can be accurately determined from cross-fiber sections without making any sheet assumptions. We have now expanded on those ideas and created a method to perform the quantitative histological investigation of the rat hearts in a way that is both timely and cost effective. We developed a processing method that preserves the orientation of the fiber and sheet angles. This method was carried out using plastic embedding since the dehydration process used in paraffin embedding has a tendency to grossly distort tissue. Once the heart was fixed in formalin, we then removed the septum and sliced it several times vertically. This allowed us to image the tissue at several depths and find an average fiber angle for each slice. Next, the specimen was hardened, and the sheet orientation was evaluated using polarized light. Once both fiber and sheet angles were obtained from several depths within the septum, we then constructed a three-dimension model of the wall. This method was both cost effective and less time consuming than previous ones and will be a method that can be used in the future to compare the myocardial tissue of diseased and healthy rat hearts so that we may better understand the mechanical functions of the heart as it remodels due to disease.
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Rawlins, D. J. "Quantitative aspects of rat heart structure and function." Thesis, University of York, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374191.
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Legendre, Lucas. "Les crocodiles sont-ils devenus secondairement ectothermes ? : étude paléohistologique." Electronic Thesis or Diss., Paris 6, 2014. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2014PA066307.pdf.
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Les archosaures sont un clade de vertébrés comprenant les oiseaux, les crocodiliens, ainsi que de nombreux groupes fossiles. Ce groupe fait depuis plusieurs décennies l'objet d'un important débat parmi les paléontologues quant à l'évolution du thermométabolisme au sein de ses différentes lignées. L'hypothèse classique considère que seuls les oiseaux modernes sont endothermes, tandis que tous les autres archosaures sont ectothermes. L'histologie osseuse permet d'étudier plusieurs traits relatifs au thermométabolisme impossibles à mesurer sur des spécimens fossiles ; c'est pourquoi nous avons utilisé des caractères mesurés sur des coupes histologiques d'os longs.Nous nous sommes consacrés dans une première partie à une revue détaillée de la mesure du signal phylogénétique pour des caractères ostéohistologiques dans deux clades de vertébrés, ce qui nous a permis de mieux définir l'approche à suivre dans la construction de nos modèles prédictifs.Après une étude préliminaire consacrée à l'élaboration d'un modèle prédictif du taux de croissance osseuse, nous avons construit un modèle global capable de prédire directement le taux métabolique de nos spécimens fossiles. Nos résultats montrent que la majorité des archosaures de notre échantillonnage étaient endothermes. Cela implique que le dernier ancêtre commun des archosaures était probablement endotherme, et que les crocodiliens sont donc devenus secondairement ectothermes, probablement en réponse aux contraintes du milieu aquatique. Des études plus spécifiques sur la lignée des pseudosuchiens devraient permettre de déterminer à quel niveau de l'arbre phylogénétique s'est effectué le retour à cet état ectothermeArchosaurs are a clade of vertebrates that includes birds, crocodiles, and numerous fossil groups. This clade has been a matter of debate among paleontologists for decades concerning the evolution of thermometabolism in its different lineages. The classical hypothesis considers that only modern birds are true endotherms, whereas all other archosaurs are ectotherms. Bone histology allows to study several traits linked to bone growth rate and thermometabolism, otherwise impossible to estimate on fossil specimens; for this reason, we used characters measured on long bone histological sections.In the first section, we extensively reviewed the measure of phylogenetic signal for osteohistological features in two clades of vertebrates, which was then used to define the methodology for building our predictive models.After a preliminary study during which we built a predictive model for bone growth rate, we built a global model to predict the metabolic rate of our fossil specimens, using both histological features and phylogenetic information for each specimen. Our results show that a majority of archosaurs in our sample were endotherms. This implies that the last common ancestor of archosaurs was likely an endotherm, and that modern crocodiles became secondarily ectothermic, probably in response to their aquatic environment. More specific studies on pseudosuchians should allow to precisely identify the level of the phylogenetic tree at which the ectothermic state was acquired, as well as adaptive constraints behind this acquisition
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Rowe, K. A. "Quantitative microscopic studies of normal and dystrophic chicken muscle." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375318.
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Leclerq, Pascale. "Quantitative post-mortem study of cortical interneurons in chronic schizophrenia." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300445.
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Warui, C. N. "Quantitative observations on the structural characteristics of the avian kidney." Thesis, University of Liverpool, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370841.
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Scott-Park, Freda Marion. "Quantitative assessment of the cardiac function in dogs using the apexcardiogram." Thesis, University of Edinburgh, 1986. http://hdl.handle.net/1842/29988.
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Ferey, Laurence. "Contribution a l'analyse histologique et ultrastructurale quantitatives de la differenciation cellulaire de la muqueuse oesophagienne humaine." Caen, 1986. http://www.theses.fr/1986CAEN2012.
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Ferey, Laurence. "Contribution à l'analyse histologique et ultrastructurale quantitatives de la différenciation cellulaire de la muqueuse oesophagienne humaine." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37597576c.
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Hudson, Kristen Kay. "Development of imaging methods to quantify the laminar microstructure in rat hearts." Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/1271.
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The way in which the myocardium responds to its mechanical environment must be understood in order to develop reasonable treatments for congestive heart failure. The first step toward this understanding is to characterize and quantify the cardiac microstructure in healthy and diseased hearts. Myocardium has a laminar architecture made up of myolaminae, which are sheets of myocytes surrounded by a collagen weave. By enhancing the contrast between the myocytes and the surrounding collagen, the myocardium can be investigated and its laminar structure can be quantified. Many of the techniques that have been used to view the microstructure of the heart require the use of toxic or caustic chemicals for fixation or staining. An efficient imaging method that uses polarization microscopy and enhances the contrast between the collagen and myocytes while minimizing the use of harmful chemicals was developed in this research. Collagen is birefringent; therefore its visibility should be enhanced through polarization microscopy and image processing. The sheet angles were viewed directly by cutting slices of a rat septum perpendicular to the fiber angle. Images of different polarization combinations were taken and a region of interest was selected on the sample. Image processing techniques were used to reduce the intensity variation on the images and account for the variable gain of the camera. The contrast between the collagen and myocytes was enhanced by comparing adjusted images to the background and looking at a single image this comparison produced. Although the contrast was enhanced, the embedding media reduced the collagen signal and the enhancement was not as striking as expected.
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Watanabe, Plauto Christopher Aranha. "Efeitos de baixas doses de radiação sobre a genese e evolução do tecido de granulação : analises quantitativa e qualitativa." [s.n.], 1992. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288220.
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Orientadores: Mario Roberto Vizioli , Frab Norberto BoscoloDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O presente trabalho teve por finalidade pesquisar a genese e evolução do tecido de granulação induzido experimentalmente em ratos, sob a ação local de baixas doses de radiação X, comparando-se os possíveis efeitos produzidos quando da aplicação em dose única e em dose dividida, com o tecido de granulação normal¿Observação: O resumo, na íntegra poderá ser visualizado no texto completo da tese digital
Abstract: The purpose of this search was to study histological and histoquimical aspects of the genesis and evolution of artifficially induced granulation tissue under the effect of low doses X-irradiation. By the other hand, it was also compared the effects produced by X-irradiation applied in simple and divided doses with the untreated granulation tissue aspects ...Note: The complete abstract is available with the full electronic digital thesis or dissertations
Mestrado
Radiologia
Mestre em Odontologia
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Pover, P. S. "A quantitative study of the interaction between Microsphaera alphitoides and the phylloplane flora of Quercus robur." Thesis, University of Hertfordshire, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355855.
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Jorio, Aziza. "Dynamique folliculaire comparee pendant la periode prepubere chez deux races s de brebis differant par leur taux d'ovulation : la d'man et la timahdite." Paris 6, 1987. http://www.theses.fr/1987PA066446.
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Santos, José Miguel de Oliveira Dias Prudente dos. "Comparative effects of sediments contaminated by carcinogenic and non-carcinogenic PAHs in Dicentrarchus labrax: a semi-quantitative histopathological approach." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/10771.
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Dissertação para obtenção do Grau de Mestre em Engenharia do AmbientePolycyclic Aromatic Hydrocarbons (PAHs) are considered priority pollutants due to their high risk to environmental and human health. Due to their hydrophobic character, in aquatic environments, these substances tend to adsorb to the particulate fraction and accumulate in the sediments. Despite their division into carcinogenic, potentially carcinogenic and non-carcinogenic to humans, little is known about the differences between modes of action of carcinogenic and non-carcinogenic PAHs in aquatic organisms. In order to understand the toxicity mechanisms of these two classes, laboratory assays were performed with juvenile basses (Dicentrarchus labrax) exposed to contaminated artificial sediments for 28 days. Sediment were spiked with environmentally-relevant concentrations of benzo[b]fluoranthene (a carcinogenic PAH) and phenanthrene (non-carcinogenic), either isolated or in mixture. Exposure effects were analysed through an indice-based semi-quantitative histopathological approach in hepatic tissue, due to the role of liver in the accumulation and detoxification of xenobiotics. Overall, significant alterations in the hepatic tissue were detected relatively to control tests, either for isolated or mixture assays, despite the low levels of exposure. Individuals exposed to benzo[b]fluoranthene presented higher severity and number of hepatic lesions compared to phenanthrene. Furthermore different toxicants caused different patterns of histopathological lesions and alterations. The results also show that histopathological condition indices of mixture-exposed individuals do not match the expected additive effects, suggesting a possible synergistic interaction effect between the contaminants. This work allows the conclusion that, albeit considered low, environmentally-relevant concentrations of PAHs in sediments may cause adverse effects in organisms, in this case, a demersal fish. On the other hand, results also suggest that a non-carcinogenic PAH may be responsible for considerable toxic effects, even in moderate concentrations. Altogether, requalifying risk assessment for these substances becomes of the upmost importance since PAHs (as other pollutants) are usually present in the environment in complex mixtures.
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SMALLS, LOLA ROMING KELLY. "DEVELOPMENT OF QUANTITATIVE MODELS FOR THE INVESTIGATION OF GYNOID LIPODYSTROPHY (CELLULITE)." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1115923913.
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Gabbott, P. L. A. "Quantitative neurohistological correlates of visual deprivation in the visual system of the rat and GABA immunocytochemistry of the rat cerebellum and dorsal lateral geniculate nucleus." Thesis, Open University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354999.
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Al-Ramadhani, Salma. "Metasin : an intra-operative Real-Time Quantitative Reverse Transcription Polymerase-Chain Reaction (RTqPCR) assay to detect metastatic breast cancer in sentinel lymph nodes." Thesis, Queen Mary, University of London, 2014. http://qmro.qmul.ac.uk/xmlui/handle/123456789/7870.
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The most important prognostic factor in breast cancer is the presence or absence of metastases in axillary lymph nodes. Frozen section and touch imprint cytology are conventional intra-operative methods used in the detection of metastatic breast cancer with varying sensitivities and specificities. The limitation of these methods led to the development of alternative molecular diagnostic tests, such as GeneSearch, a commercial real-time quantitative Polymerase Chain Reaction (RT-qPCR) assay that allows for an intra-operative diagnosis of metastatic breast cancer. When the GeneSearch assay was discontinued, Metasin was developed as an in-house RT-qPCR replacement assay. Metasin targets the epithelial cell marker cytokeratin 19 (CK19) and the breast marker mammaglobin (MGB) mRNA to confirm the presence or absence of metastatic disease, whilst the reference gene porphobilinogen deaminase (PBGD) acts as a positive control for the performance of the assay. The optimised assay can produce a result within 32 minutes allowing it to be used in the intra-operative setting to detect metastatic breast cancer in sentinel lymph nodes. 154 archived lymph node homogenates that were previously analysed by both GeneSearch and histology in parallel were used to validate Metasin. Out of 154 cases, 148 showed concordance with both GeneSearch and Metasin with 111 cases being negative and 37 cases being positive. There were six discordant cases, four in which only Metasin detected metastases and two in which only GeneSearch picked up metastases. Out of the four Metasin-only positive cases, three were found to be positive on histology after deeper levels were cut in the slices sent for histological assessment. Therefore, one case could not be shown histologically to be positive for metastases. There were two cases that were missed by Metasin but picked up by GeneSearch. One case was positive on histology and the second case negative for histology. The error rate for Metasin was 3.89%. The sensitivity and specificity of the Metasin assay were found to be 95% and 98% respectively, and the positive and negative predictive values were 90% and 98% respectively. These results are comparable to those of GeneSearch. Metasin had an assay time of less than 45 minutes and was operated by biomedical scientists. The results of the validation process were deemed acceptable for the assay to be run live and used in the clinical setting. Metasin continues to provide breast cancer patients at Princess Alexandra Hospital with all the advantages that a molecular intra-operative diagnostic service provides.
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Galvez, Lopez Didiana. "Etude des déterminants structuraux et génétiques de la texture de la pomme." Nantes, 2011. http://www.theses.fr/2011NANT2036.
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La texture est un critère majeur déterminant la qualité de la pomme. Elle dépend de facteurs cellulaires (parois cellulaires et pression de turgescence) et histologiques à différentes échelles lesquelles sont sous contrôle génétique. L’objectif de cette thèse était d’identifier des marqueurs génétiques associés à la texture du fruit. Une descendance de 150 individus a été phénotypée sur deux années à trois stades de conservation pour des caractères sensoriels et mécaniques, et pour des variables histologiques et biochimiques de la paroi cellulaire. Des corrélations entre des mesures instrumentales et sensorielles et des paramètres histologiques ont été établies alors qu’aucune n’a été trouvée avec les variables biochimiques. Les valeurs d’héritabilité varient de 0. 16 à 0. 94 pour l’ensemble des variables. La recherche de QTL s’est focalisée sur les 31 caractères les plus héritables. Au total, 127 QTL ont été localisés dans 36 régions réparties sur les 17 groupes de liaison du pommier : 25 codent pour les variables instrumentales et sensorielles, sept pour des paramètres histologiques, 27 pour des structures biochimiques pariétales. 19 régions montrent une co-localisation entre des caractères sensoriels et/ou instrumentals avec les mesures histologiques et/ou biochimiques, révélant pour la première fois des liens entre le contrôle génétique de caractères de texture de la pomme avec ceux de déterminants structuraux de la paroi. Ces résultats originaux offrent une base pour la recherche de gènes les contrôlant. Ils ouvrent également de nouvelles perspectives pour l’amélioration de la qualité de la pomme par sélection assistée par marqueurs moléculairesTexture is a major criterion of apple quality. It depends of cellular (cell wall and turgor pressure) and histological factors at different scales, which are under genetic control. The objective of this thesis was to identify new genetic markers related to fruit texture traits. A progeny of 150 individuals was phenotyped over two years at three different storage dates for sensory and mechanical traits, for histological parameters and cell wall biochemistry. Significant correlations were found between texture and histological traits, but no correlations were established with cell wall structures. The heritability values for all the traits varied from 0. 16 to 0. 94. The QTL mapping was focused on the 31 most heritable variables. A total of 127 QTL were located on 36 regions within the 17 apple linkage groups : 25 map for instrumental and sensory parameters, seven for histological and 27 for biochemical cell wall structures. 19 regions showed co-localization between sensory and/or instrumental characters with histological and/or biochemistry, revealing for the first time links between the genetic control of apple texture traits with those of structural cell wall determinants. Three regions co- localized with candidate genes related to fruit development and ripening identified in previous studies. These original results open new perspectives for improving the quality of apple by molecular marker-assisted breeding. They also provide a basis for deciphering new genes controlling structural determinants of texture
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Nazaran, Amin. "Ultra Short MR Relaxometry and Histological Image Processing for Validation of Diffusion MRI." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/6348.
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Magnetic Resonance Imaging (MRI) is an imaging modality that acquires an image with little to no damage to the tissue. MRI does not introduce foreign particles or high energy radiation into the body, making it one of the least invasive medical imaging modalities. MRI can achieve excellent soft tissue contrast and is therefore useful for diagnosis of a wide variety of diseases. While there are a wide variety of available techniques for generating contrast in MRI, there are still many open areas for research. For example, many tissues in the human body exhibit such rapid signal decay that they are difficult to image with MRI: they are "MRI invisible". Furthermore, some of the newer MRI imaging techniques have not been fully validated to ensure that they are truly revealing accurate information about the underlying anatomical microstructure that they purport to image. This dissertation focuses on the development of new techniques in two distinct areas. First, a novel method for accurately assessing the MRI signal decay properties of tissues that are normally MRI invisible, such as tendons, ligaments, and certain pathological chemical deposits in the brain, is presented. This is termed "ultrashort MRI relaxometry". Second, two new image processing algorithms that operate on high resolution images of stained histological slices of the ex vivo brain are presented. The first of these image processing algorithms allows the semi-automated extraction of nerve fiber directionality from the histological slice images, a process that is normally done manually, is incredibly time consuming, and is prone to human error. This new technique represents one significant step in the complicated problem of attempting to validate a popular MRI technique, Diffusion Tensor Imaging (DTI), by ensuring that DTI results correlate with the true underlying physiology revealed by histological slicing and staining. The second of these image processing algorithms attempts to extract and segment regions of different "cytoarchitectonic characteristics" from stained histological slices of ex vivo brain. Again, traditional cytoarchitectonic segmentation relies on manual segmentation by an expert neuroanatomist, which is slow and sometimes inconsistent. The new technique is a first step towards automated this process, potentially providing greater accuracy and repeatability of the segmentations in a much shorter time. Together, these contributions represent a significant contribution to the body of MR imaging techniques, and associated image processing techniques for validation of newer MR neuroimaging techniques against the gold standard of stained histological slices of ex vivo brain.
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Flahauw, Emilie. "Caractérisation génétique de l'effort reproducteur de l'huitre creuse, Crassostrea gigas, dans le cadre des mortalités estivales de juvéniles : approche QTL." Thesis, La Rochelle, 2013. http://www.theses.fr/2013LAROS406/document.
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L’huître creuse, Crassostrea gigas, est une espèce dont la production aquacole représente un intérêt économique tant au niveau mondial qu’aux niveaux européen et français. Cependant, cette espèce subit des mortalités estivales enregistrées dès le début du 20ème siècle et, depuis 2008, ce phénomène s’est amplifié et menace essentiellement les huîtres juvéniles. La production aquacole d’huître creuse subit les conséquences de ces mortalités massives ; c’est pourquoi ce phénomène est étudié depuis de nombreuses années. En France, la bactérie Vibrio splendidus et le virus Ostreid Herpes Virus 1 (OsHV-1) sont le plus souvent associés aux épisodes de mortalités massives d’huîtres creuses juvéniles et il a été démontré que les individus sélectionnés pour leur résistance aux mortalités estivales étaient capables de ralentir l’augmentation de la charge virale en OsHV-1 dans leurs tissus puis de la faire régresser. Ces mêmes individus présenteraient également un effort reproducteur plus modeste que des individus sélectionnés pour leur sensibilité aux mortalités estivales. Ce travail de thèse s’inscrit dans ce contexte et a donc eu pour principal objectif d’améliorer la connaissance de l’architecture génétique de la reproduction de C. gigas en identifiant des régions du génome ou QTLs (Quantitative Trait Loci) impliquées dans l’effort reproducteur et de mettre en évidence d’éventuelles relations génétiques entre survie et reproduction, des QTLs impliqués dans la survie ayant déjà été détectés. Afin de caractériser l’effort reproducteur, il a été nécessaire de développer un ensemble de nouveaux outils. D’un point de vue biologique, 21 familles F2 ont été produites à partir des lignées sélectionnées pour leur réponse contrastée aux mortalités estivales. D’un point de vue moléculaire, de nouveaux marqueurs SNP (Single Nucleotide Polymorphism) ont été développés afin d’augmenter la densité de la carte génétique déjà disponible pour C. gigas. D’un point de vue technique, l’Imagerie par Résonance Magnétique (IRM) a permis d’observer la gamétogenèse de 300 individus d’une même famille F2 au cours de huit sessions réparties sur deux années alors que les études précédentes étaient limitées à une observation ponctuelle; les méthodes classiques d’observation de la gamétogenèse entrainant nécessairement la mort des animaux. Une forte corrélation a été mise en évidence entre les observations par IRM et par la méthode classique de l’histologie. En plus de l’estimation du rapport gonado-somatique (indice traditionnellement utilisé pour caractériser l’effort reproducteur), l’IRM a également permis d’observer des variations individuelles de la cinétique de la gamétogenèse ainsi que des différences entre les mâles et les femelles; le sexe étant identifiable sur les images obtenues par IRM. Parallèlement, 300 individus de deux autres familles F2 ont été sacrifiés pour estimer le rapport gonado-somatique par histologie. Cette approche a ainsi permis de détecter des QTLs impliqués dans de nombreux traits concernant la gamétogenèse. Des individus provenant des trois familles F2 caractérisés pour l’effort reproducteur ont été caractérisés pour la survie à un épisode de mortalités estivales. Cette étude a permis de détecter des QTLs impliqués dans le caractère « survie ». Ces QTLs correspondent, pour certains, à ceux détectés au cours d’une étude précédente. De plus, ces QTLs sont parfois colocalisés avec des QTLs impliqués dans l’effort reproducteur. Bien que la reproduction de l’huître creuse soit un caractère complexe à suivre, les nouveaux outils utilisés au cours de ce travail de thèse ont permis d’acquérir de nouvelles connaissances. Le séquençage du génome complet de Crassostrea gigas ainsi que les nouvelles méthodes de séquençage pourront peut-être permettre d’affiner les régions QTLs détectéesThe Pacific oyster, Crassostrea gigas, is a major aquacultured species whose production represents an economic interest at worldwide, european and french levels. However, this species undergoes summer mortalities recorded from the beginning of the 20th century and, since 2008, this phenomenon increased and threatens mainly juvenile oysters. Aquaculture production of oysters suffers consequences of mass mortalities, that’s why this phenomenon has been studied for many years. In France, the bacterium Vibrio splendidus and the Ostreid virus Herpes Virus 1 (OsHV-1) are often associated with mass mortality outbreaks of juveniles oysters and it was demonstrated that selected individuals for resistance to summer mortality were able to slow the increasing in viral load OsHV-1 in their tissues and then to decline it. These same individuals also present a lighter reproductive effort than individuals selected for their sensitivity to summer mortality. In this context, this study aimed to improve the knowledge of genetic architecture of reproduction of C. gigas by identifying some regions of the genome called QTLs (Quantitative Trait Loci) involved in reproductive effort and highlighting possible genetic relationships between reproduction and survival; QTLs involved in survival being already detected. To characterize the reproductive effort, it was necessary to develop a set of new tools. From a biological point of view, 21 F2 families were produced from lines selected for their contrasting response to summer mortality. From a molecular point of view, new SNPs (Single NucleotidePolymorphism) were developed to increase density of the genetic map already available for C. gigas. On a technical point of view, Magnetic Resonance Imaging (MRI) allowed to observe the gametogenesis of 300 individuals of the same family F2 during eight sessions over two years while previous studies were limited to a one-time observation because of the conventional methods of observation of gametogenesis leading necessarily to the death of the animals. A strong correlation was found between observations by MRI and observations by the conventional method of histology. In addition to the estimation of gonadic index (index traditionally used to characterize there productive effort), MRI also revealed individual variations in kinetics of gametogenesis and differences between males and females, the sex being identifiable on MRI images. In parallel, 300 individuals from two F2 families were sacrificed to estimate the gonadic index by histology. This approach enabled the detection of QTLs involved in many gametogenesis traits. Individuals from the three families characterized for F2 reproductive effort were characterized for survival during a summer mortality outbreak. This study was able to detect QTLs involved in the trait "survival". These QTLs correspond to some of those detected in a previous study. In addition, these QTLs are often collocated with QTLs involved in reproductive effort. Although there production of the Pacific oyster is a complex trait to follow, the new tools used in this thesis allowed acquiring new knowledges. The sequencing of genome of Crassostrea gigas and Next-Generation Sequencing technologies may be able to help to refine the detected QTL regions
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Nun, Nicholas. "Improving Skin Wound Healing Using Functional Electrospun Wound Dressings and 3D Printed Tissue Engineering Constructs." University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1617985844538101.
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Koerbs, Christina. "Quantitative Anatomie zweier Formen von dendritischen Dornfortsätzen an hippocampalen Pyramidenzellen." Doctoral thesis, 2019. http://hdl.handle.net/11858/00-1735-0000-002E-E5A3-B.
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Patel, Kunal. "Quantitative analysis of breast lumpectomies using histology and micro-CT data." Thesis, 2014. https://hdl.handle.net/2144/14394.
Full textAbstract:
OBJECTIVE: Breast cancer represents a significant risk in women's health, affecting many women worldwide. Current treatment options in the U.S involve a multidisciplinary approach, most often beginning with surgery to remove cancerous tissue. Evaluation of margins for cancer on excised tissue is an important part of surgery, an important predictor of survival. As a result, there has been a great deal of research interest in intraoperative margin assessment, with a focus on fast and accurate results. Micro-computed Tomography (micro-CT) has emerged as a promising avenue to this end. We hypothesize that micro-CT scans will show a statistically significant difference in radiodensity between cancerous and non-cancerous tissue at intraoperative scan times.
METHODS: 15 breast lumpectomy specimens were collected from patients undergoing surgery at Massachusetts General Hospital (MGH). Lumpectomies were scanned with a Nikon XTH225 Micro-CT scanner. Corresponding histology slides were scanned with a whole slide scanner, and matched with micro-CT scans. Representative areas of cancerous and non-cancerous tissues were segmented from micro-CT scans, and their respective radiodensity differences were tested for statistical significance.
RESULTS: 9 of 15 lumpectomy cases were successfully matched with histology sections. Of the 9 cases matched, 8 showed a statistically significant difference in mean radiodensity.
CONCLUSION: Due to potential confounds in the study, the results are difficult to deem conclusive. However, micro-CT remains a promising tool in margin assessment, and could be fit for clinical use with further study.
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Rocha, Carolina da Ponte. "Semi-Automatic histology analysis of ovine pelvic tissues with 3D structural and quantitative analysis." Master's thesis, 2018. https://repositorio-aberto.up.pt/handle/10216/113152.
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Rocha, Carolina da Ponte. "Semi-Automatic histology analysis of ovine pelvic tissues with 3D structural and quantitative analysis." Dissertação, 2018. https://repositorio-aberto.up.pt/handle/10216/113152.
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Van, Dyk Jacobus C. "A qualitative and quantitative assessment of the normal histology of selected target organs of Clarias Gariepinus and Oreochromis mossambicus." Thesis, 2008. http://hdl.handle.net/10210/877.
Full textAbstract:
A histological assessment allows aquatic scientists to assess fish health in polluted aquatic ecosystems at tissue and cellular level. However, a firm knowledge and understanding of normal histological structure is essential to ensure accurate and objective results. Hence, the histologist must be able to distinguish between toxicant induced lesions and the range of histological characteristics considered to be normal for that specific species. However, limited histological reference material and data describing normal conditions are available for southern African fish species. The aim of this baseline study was to establish reference material, both qualitative and quantitative, for two southern African freshwater fish species used as indicator species in toxicity studies at the University of Johannesburg, Clarias gariepinus and Oreochromis mossambicus. The reference material includes descriptive histology of selected target organs, and the associated values and intervals for related quantitative health aspects including somatic indices, condition factor, blood parameters (haematocrit and plasma proteins) and quantitative histological results. Essentially, this project originated from a need to better understand the normal histology of C. gariepinus and O. mossambicus, as a range of histological characteristics were identified in control groups in previous toxicity studies which could not be confirmed to be associated with normal conditions. To be able to conduct a baseline study, with the purpose of establishing reference material, it was essential that the history of the specimens be known and documented including age, sexual maturity, nutritional status and physical and chemical water quality data. The project therefore involved the breeding of fish specimens under controlled conditions. A subsequent necropsy and qualitative and quantitative histological assessments were executed on five target organs (usually included in toxicity studies within the department): liver, gills, gonads, heart and kidney. Fish of both species were bred in an environmental room in reconstituted, reverse osmosis water and reared until sexually mature. Twenty specimens with an approximately 50:50% sex ratio were collected for both species. A necropsy was performed on each specimen and tissue samples of the selected target organs were processed using standard techniques, and prepared for the qualitative and quantitative histological assessments using light microscopy. The results The results showed that no macroscopic abnormalities were identified during the necropsy regarding external features or internal organs of the specimens within the sample groups, and all fish appeared to be in good health. The target organs were then examined microscopically, followed by a description of the normal histological structure (qualitative assessment). In addition, the target organs were assessed by means of a specific quantitative histological assessment protocol, which provides a standardised methodology of criteria to objectively assess fish health (quantitative assessment). Histological alterations identified during this assessment were quantified and subsequent reference index values could be calculated for each organ.Dr. G.M. Pieterse
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Cook, Jason Ray. "Photoacoustic microscopy of nanoparticles in cells and tissues." 2013. http://hdl.handle.net/2152/21882.
Full textAbstract:
Molecular photoacoustic imaging is an exciting new field that promises to visualize molecular indicators of disease. The objective of this dissertation is to progress molecular imaging by providing a photoacoustic microscopy platform to better validate in vivo molecular photoacoustic imaging, diagnose disease, and study fundamental photoacoustic processes. Initially, a custom photoacoustic microscope was developed to provide high-sensitivity and high-resolution of both endogenous and exogenous contrast agents in thin cell or tissue samples. After characterization, the photoacoustc microscope was first used to image the hemoglobin distribution in the spleen and liver. The photoacoustic microscope was then used to image nanoparticles in injured and diseased cell and tissues samples. These images can be used for in vivo photoacoustic image validation or, independently, as a diagnostic tool for disease. To enhance the utility of photoacoustic microscopy, a quantitation technique was developed for nanoparticles in cells and tissues. Quantitative photoacoustic imaging has the potential to replace mass spectrometry and histology for a wide array of molecular imaging and targeting studies. Finally, photoacoustic microscopy was used to study the nonlinear dependence of the photoacoustic pressure with laser fluence of nanoparticle-loaded cells. New discoveries about the nonlinear dependence with nanoparticle concentration and cell type are presented. These new discoveries may provide the framework for a new type of photoacoustic imaging with contrast that is cell-type specific. Overall, the work described in this dissertation can be used to improve diagnosis and accelerate clinical translation of new and emerging molecular imaging techniques.text
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"Quantitation of iron in the liver, pancreas and heart of hospital patients in Hong Kong." Chinese University of Hong Kong, 1993. http://library.cuhk.edu.hk/record=b5887704.
Full textAbstract:
by Yim-kam Kwong.Thesis (M.Phil.)--Chinese University of Hong Kong, 1993.
Includes bibliographical references (leaves 119-133).
ACKNOWLEDGEMENT --- p.vii
LIST OF TABLES --- p.viii
LIST OF FIGURES --- p.x
ABSTRACT --- p.1
SECTION
Chapter 1. --- INTRODUCTION --- p.3
Chapter 2. --- LITERATURE REVIEW --- p.6
Chapter 3. --- MATERIALS AND METHODS --- p.39
Chapter 4. --- RESULTS --- p.61
Chapter 5. --- DISCUSSION --- p.103
Chapter 6. --- CONCLUSION --- p.116
REFERENCES --- p.119
APPENDIX --- p.134
Chapter SECTION 1 --- INTRODUCTION --- p.3
Chapter SECTION 2 --- LITERATURE REVIEW --- p.6
Chapter 2.1 --- IRON --- p.6
Chapter 2.1.1 --- CHEMISTRY --- p.6
Chapter 2.1.2 --- METABOLISM --- p.6
Chapter 2.1.2.1 --- Homeostasis --- p.6
Chapter 2.1.2.2 --- Absorption --- p.8
Chapter 2.1.2.3 --- Transportation - Role of transferrin in iron transport --- p.9
Chapter 2.1.2.4 --- Storage --- p.10
Ferritin --- p.11
Haemosiderin --- p.13
Chapter 2.2 --- IRON OVERLOAD --- p.14
Chapter 2.2.1 --- AETIOLOGY --- p.14
Chapter 2.2.2 --- PREVALENCE --- p.15
Chapter 2.2.3 --- MECHANISM --- p.16
Chapter 2.2.4 --- PATHOLOGY OF IRON OVERLOAD --- p.17
Chapter 2.2.4.1 --- Increased absorption of iron from the diet --- p.18
Chapter 2.2.4.2 --- Parenteral administration of excess iron --- p.21
Chapter 2.2.4.3 --- Increased iron absorption combined with transfusional overload --- p.22
Chapter 2.2.4.4 --- Miscellaneous conditions --- p.23
Chapter 2.2.5 --- CLINICAL PRESENTATION --- p.24
Chapter 2.2.6 --- EFFECT OF IRON OVERLOAD --- p.25
Chapter 2.2.6.1 --- Role of iron in lipid peroxidation --- p.25
Chapter 2.2.6.2 --- Iron and neoplasia --- p.26
Chapter 2.3 --- ASSESSMENT OF IRON OVERLOAD --- p.26
Chapter 2.3.1 --- NON-SERUM PARAMETER --- p.26
Chapter 2.3.1.1 --- Localization of stored iron --- p.27
Chapter 2.3.1.2 --- Morphometric assessment of hepatic iron in liver biopsy --- p.30
Chapter 2.3.1.3 --- Hepatic iron concentration --- p.31
Chapter 2.3.1.4 --- Atomic absorption spectrophotometry --- p.32
Chapter 2.3.1.5 --- Hepatic imaging studies --- p.33
Chapter 2.3.2 --- SERUM PARAMETERS --- p.34
Chapter 2.3.2.1 --- Serum ferritin measurement --- p.34
Chapter 2.3.2.2 --- Serum iron --- p.36
Chapter 2.3.2.4 --- Transferrin saturation --- p.37
Chapter SECTION 3 --- MATERIALS AND METHOD --- p.39
Chapter 3.1 --- SUBJECTS --- p.39
Chapter 3.1.1 --- SOURCE OF TISSUE SAMPLES AND CASE SELECTION --- p.39
Chapter 3.1.1.1 --- The controls --- p.39
Chapter 3.1.1.2 --- The transfusion group --- p.39
Chapter 3.1.1.3 --- The non-transfusion group --- p.40
Chapter 3.1.1.4 --- The total group --- p.40
Chapter 3.2 --- METHODS --- p.40
Chapter 3.2.1. --- HISTOLOGICAL METHOD --- p.44
Chapter 3.2.1.1 --- Haematoxylin and Eosin Stain --- p.47
Chapter 3.2.1.2 --- Perls' Prussian Blue Method --- p.49
Chapter 3.2.1.3 --- The Rowe's Method of Iron Deposition --- p.47
Chapter 3.2.1.4 --- Method 1 --- p.48
Chapter 3.2.1.5 --- Method2 Estimation and grouping of % area --- p.49
Chapter 3.2.1.6 --- "Comparison of Rowe's method, and the two histological iron grading methods" --- p.54
Chapter 3.2.2 --- CHEMICAL MEASUREMENT --- p.55
Chapter 3.2.2.1 --- Sectioning of paraffin liver blocks for chemical measurement --- p.55
Chapter 3.2.2.2 --- Paraffin removal --- p.56
Chapter SECTION 4 --- RESULTS --- p.61
Chapter 4.1 --- HISTOLOGICAL ASSESSMENT --- p.61
Chapter 4.1.1 --- HISTOLOGICAL STUDY --- p.61
Chapter 4.1.2 --- SEX DISTRIBUTION --- p.65
Chapter 4.1.3 --- AGE DISTRIBUTION --- p.65
Chapter 4.2 --- CHEMICAL MEASUREMENT --- p.81
Chapter 4.2.1 --- EVALUATION OF ANALYTICAL PRECISION --- p.84
Chapter 4.2.2 --- RESULT OF CHEMICAL MEASUREMENTS --- p.81
Chapter 4.2.3 --- ASSOCIATED CONDITIONS IN PATIENTS WITH LIVER TISSUE IRON > 50 μMOL/G --- p.86
Chapter 4.3 --- CORRELATION OF HISTOLOGICAL ASSESSMENT WITH CHEMICAL MEASUREMENT --- p.88
Chapter 4.3.1 --- CORRELATION OF HISTOLOGICAL ASSESSMENT WITH CHEMICAL MEASUREMENT BY METHOD 1 --- p.88
Chapter 4.3.2 --- CORRELATION OF ASSESSMENT WITH CHEMICAL MEASUREMENT BY METHOD 2 --- p.89
Chapter 4.3.2.1 --- Percentage area --- p.95
Chapter 4.3.2.2 --- Score --- p.96
Chapter 4.4 --- PANCREATIC AND MYOCARDIAC HAEMOSIDEROSIS --- p.100
Chapter 4.4.1 --- METHOD 2 --- p.100
Chapter SECTION 5 --- DISCUSSIONS --- p.103
Chapter SECTION 6 --- CONCLUSIONS --- p.116
REFERENCES --- p.119
APPENDIX --- p.134
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Xu, Hai. "Structural Modeling and Analysis of Structures in Aorta Images." Thesis, 2011. http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-9779.
Full textAbstract:
Morphology change analysis of aorta images acquired from biological experiments plays a critical role in exploring the relationship between lamina thickness (LT), interlamellar distance (ILD) and fragmentation (furcation points) with respect to pathological conditions. An automated software tool now is available to extract elastic laminae (EL) and measure LT, ILD and fragmentation along their ridge lines in a fine detailed aspect. A statistical randomized complete block design (RCBD) and F-test were used to assess potential (non)-uniformity of LT and ILD along both radial and circumferential directions. Illustrative results for both normotensive and hypertensive thoracic porcine aorta revealed marked heterogeneity along the radial direction in nearly stress-free samples. Quantifying furcation point densities were also found that can offer new information about potential elastin fragmentation, particularly in response to increased loading due to hypertension.
Furthermore, when biological scientists analyze the elastic lamina structure, how to automatically generate a macro-level geometric parameter mapping might greatly help them understand the over-all morphology changes of blood vessel cross section. In this dissertation, another automated system is designed to quickly locate more pronounced EL branches to construct layer level abstraction of LT/ILD measurements and transform the sparse pixel level information to dense normalized Virtual Layer Matrix (VLM). The system can automatically compute the EL orientations, identify pronounced ELs, transform the denoised LT measurement points onto a VLM and then provide statistics/segmentation analysis. By applying the k-means segmentation technique to VLMs of LT-ILD, one can easily delineate regions of normal vs. hypertrophic and/or hyperplasia LT-ILD measurements for cross-image references.