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Extraction de signatures de bactéries par microspectroscopie Raman et chimiométrie : application à l’étude de la composition biologique des aérosols dans l’environnement / Extraction of bacterial signatures by Raman microspectroscopy and chemometrics : application to the study of the biological composition of aerosols in the environmentSignour, Thomas 11 December 2017 (has links)
Depuis plusieurs années, l’étude et le contrôle de la qualité de l’air sont au cœur de toutes les préoccupations. En 2012, la DGA (Direction Générale de l’Armement) met en place le programme ASTRID (Accompagnement Spécifique des Travaux de Recherches et d’Innovation Défense) accompagnant les travaux de recherche duale civile et militaire. Cette thèse s’inscrit dans cette démarche et propose d’étudier la faisabilité du concept de détection et d’identification rapides des microorganismes présents dans un échantillon d’air par microspectroscopie Raman, avec une résolution au niveau de l’espèce. Pour cela, nous construisons un modèle chimiométrique de classification des microorganismes représentatifs de la biodiversité naturelle en acquérant, sans a priori, d’une part les spectres Raman de ces microorganismes après biocollecte et étalement sur la lame d’un microspectromètre Raman, et d’autre part les séquences génomiques codant les ARN 16S de ces mêmes microorganismes.Les travaux de recherche présentés dans cette thèse présentent donc les différentes études mises en œuvre lors du développement d’un nouveau protocole permettant l’analyse des bactéries issues d’aérosols naturels environnementaux. Nous démontrons la nécessité d’optimiser l’acquisition des spectres Raman sur les bactéries et le traitement statistique des données spectrales permettant le développement de modèles de classification présentant des taux de reconnaissance élevés. / For several years, the study and the control of the quality of the air are at the heart of all the concerns. In 2012, the DGA (Direction Générale de l’Armement) employs the ASTRID program (Accompagnement Spécifique des Travaux de Recherches et d’Innovation Défense), to accompany the dual civil and military research work. This thesis is part of this approach and proposes the feasibility study, by Raman microspectroscopy, of the concept of rapid detection and identification of microorganisms present in an air sample, with a resolution at the species level. For this, we construct a chemometric model for the classification of micro-organisms representative of the natural biodiversity. Such a model is built by acquiring, without a priori i) the Raman spectra of these microorganisms after biocollection; and ii) the genomic sequences encoding the 16S RNAs of these same microorganisms. The research presented in this thesis therefore presents the different studies carried out during the development of a new protocol allowing the analysis of bacteria from natural environmental aerosols. We demonstrate the need to optimize the acquisition of Raman spectra on bacteria and the statistical processing of spectral data that allows the development of classification models with high recognition rates.
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The pathophysiological and clinical significance of TP53 in bladder cancerGriffiths, T. R. Leyshon January 1999 (has links)
No description available.
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Molecular analysis of normal human skin and basal cell carcinoma using microdissection based methods /Asplund, Anna, January 2005 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2005. / Härtill 5 uppsatser.
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Differential localization of mRNA using laser microdissection in the polarized hyphal tip of Fusarium oxysporumTelu, Kalyani. January 2009 (has links)
Thesis (M.S.)--University of Delaware, 2009. / Principal faculty advisor: Kirk J. Cymmek, Dept. of Biological Sciences. Includes bibliographical references.
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Microdissection and molecular cloning of extra small ring chromosomes of human / by Yu-Yan Fang.Fang, Y. Y. January 1998 (has links)
Copies of author's previously published articles inserted. / Errata pasted onto front end-paper. / Bibliography: leaves 111-139. / xii, 139, [34] leaves, [25] leaves of plates : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Defines the origin of ring extra structurally abnormal chromosomes (ESACs), relates the genetic content of different ring ESACs derived from the same chromosome with the patient's pheuotype, generates probes for diagnostic use and refines the critical region of Wolf-Hirschhorn syndrome. / Thesis (Ph.D.)--University of Adelaide, Dept. of Paediatrics, 1998
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Microdissection and molecular cloning of extra small ring chromosomes of human /Fang, Yu-Yan. January 1998 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Dept. of Paediatrics, 1998. / Copies of author's previously published articles inserted. Errata pasted onto front end-paper. Includes bibliographical references (leaves 111-139).
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Development of On-Tissue Mass Spectrometric Strategies for Protein Identification, Quantification and Mapping / Développements de stratégies de spectrométrie de masse sur tissu pour l’identification, la quantification et la cartographieQuanico, Jusal 11 July 2014 (has links)
L’imagerie par spectrométrie de masse est une technique sans marquage permettant la détection et la localisation de protéines à partir de coupes de tissus. Afin de répondre à des problématiques biologiques, le nombre de protéines identifiées doit être amélioré. Une stratégie consiste à réaliser une micro-jonction liquide sur des régions particulières des coupes de tissus afin d’extraire les peptides issus de la digestion in situ des protéines. Plus de 1500 protéines ont identifié sur une zone de 650µm, correspondant à environ 1900 cellules. Une corrélation entre ces données avec celles générées par MSI a augmenté le nombre de protéines localisées. Afin d’obtenir dans le même temps, la localisation et l’identification de protéines, une méthode consiste à réaliser la microdissection de l’ensemble de la coupe après l’avoir déposée sur une lame recouverte de parafilm. PAM a également été appliquée à l’étude de l'expression différentielle de protéines dans des tumeurs de prostate. Les résultats ont permis d’identifier des biomarqueurs potentiels tels que des protéines complexées avec des petits ARN nucléolaires. Enfin, la faisabilité des méthodes MS appliquées à l’étude structurale de protéines, tel que l'échange deutérium ou le pontage chimique, ont été examinés directement sur tissu. Les résultats préliminaires suggèrent qu’une étude structurale de protéines est possible afin de déterminer des changements de structures entrainés par la modification du microenvironnement. Réunis ensemble, ces méthodes MS d'analyses directes fournissent un moyen robuste d’étude de protéines dans leur état natif afin de fournir des indications sur leur rôle dans des systèmes biologiques. / Mass spectrometry-based methods for direct tissue analysis, such as MS imaging, are label-free techniques that permit the detection and localization of proteins on tissue sections. There is a need to improve the number of protein identifications in these techniques for them to comprehensively address biological questions. One strategy to obtain high protein IDs is to realize liquid microjunction on localized regions of tissue sections to extract peptides from the in situ digestion of proteins. More than 1500 proteins were identified in a 650µm spot, corresponding to about 1900 cells. Matching these IDs with those from MSI increased the number of localized proteins. In order to achieve simultaneous identification and localization of proteins, a method consisting of microdissecting entire tissue sections mounted on parafilm-covered slides was developed. Spectral counting was then used to quantify identified proteins, and the values were used to generate images. PAM was also used to examine the differential expression of proteins on prostate tumors. Results identified potential biomarkers such as proteins in complex with small nucleolar ribosomal RNAs. Lastly, the feasibility of applying MS methods of structural analysis, such as deuterium exchange and crosslinking, directly on tissue was examined. Preliminary results suggest the possibility of this approach, which could be significative by permiting the determination of protein structural changes for a given microenvironment. Taken together, these direct MS analysis methods provide a robust means of analyzing proteins in their native state and are expected to provide insights to their role in biological systems.
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Colorado microdissection needle versus cold steel scalpel for incisions in third molar surgeryMohamed, Allie January 2014 (has links)
Magister Chirurgiae Dentium - MChD / This study compares the CMN to the steel scalpel by assessing incision time, incisional blood loss, postoperative pain, wound healing, and the incidence of lingual and long buccal nerve injury. Twenty standardised cases were included in an analytical prospective case series. Each case had one side cut with CMN and the other side with steel scalpel. Third molar surgery is the most commonly performed procedure by maxillo-facial and oral surgeons, and is associated with expected but transient sequelae such as pain, swelling and trismus. Modalities to reduce the severity of these sequelae are desirable. Several studies report that the use of conventional electrosurgical instruments and the Colorado Microdissection Needle (CMN) resulted in significant reductions in cutting time, incisional blood loss, postoperative pain, with no evidence of increased incidence of wound complications such as dehiscence and infection.
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Estudo citogenético de espécies de Dendropsophus (Anura: Hylidae) / Cytogenetic studies of species of Dendropsophus (Anura: Hylidae)Rocha, Lívia Sartoratto Rodrigues Teixeira, 1985- 24 August 2018 (has links)
Orientador: Luciana Bolsoni Lourenço Morandini / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-24T04:46:17Z (GMT). No. of bitstreams: 1
Rocha_LiviaSartorattoRodriguesTeixeira_M.pdf: 2334745 bytes, checksum: a9acefe033f1368290ff1d80292a3ebd (MD5)
Previous issue date: 2013 / Resumo: O gênero Dendropsophus (Anura: Hylidae) é composto por 94 espécies neotropicais, das quais somente 31 foram estudadas citogeneticamente. Embora as espécies desse gênero apresentem o mesmo número cromossômico (2n=30), diferem quanto ao número fundamental e em relação à localização de NORs. Entretanto, a escassez de marcadores citogenéticos e o alto número de espécies com cariótipos ainda não descritos impedem inferências acerca dos possíveis eventos envolvidos na diferenciação cariotípica nesse gênero. Com o intuito de fornecer novos dados para a análise evolutiva cariotípica em Dendropsophus, no presente trabalho foram descritos os cariótipos de duas espécies do grupo de D. marmoratus, D. seniculus e D. soaresi, ampliada a caracterização dos cariótipos de D. decipiens, D. meridianus e descrito o de D. werneri, três espécies do grupo de D. microcephalus. Para a localização cromossômica do gene ribossomal 5S foram utilizadas sequências isoladas de D. soaresi. Também foram utilizadas sondas para verificar a localização cromossômica de sequências teloméricas em todas as espécies estudadas. Por fim, na tentativa de gerar sondas cromossômicas para futuros estudos dos cromossomos telocêntricos encontrados em Dendropsophus, experimentos de pintura cromossômica foram conduzidos com D. nanus e D. walfordi. Dendropsophus seniculus e D. soaresi apresentaram cariótipos muito semelhantes, com a NOR localizada no braço longo dos cromossomos do par 9. Tais cariótipos se assemelham também àqueles das outras três espécies já cariotipadas do grupo de D. marmoratus (D. marmoratus, D. melanargyreus e D. nahdereri), embora o cariótipo de D. nahdereri difira dos demais por apresentar a NOR no braço curto dos cromossomos do par 1. Dois tipos de sequências de DNAr 5S foram isolados de D. soaresi. A sequência identificada como do tipo I é composta por 512 pb, dos quais 390 pb pertencem à região não-transcritora (NTS); já a sequência do tipo II apresenta NTS com apenas 249 pb. A sequência nucleotídica do DNAr 5S do tipo I é idêntica a uma sequência encontrada no hilídeo Gastrotheca riobambae. Quando utilizado como sonda, esse segmento de DNAr 5S foi mapeado no braço longo dos cromossomos do par 2 de D. seniculus e D. soaresi. Sondas compostas por sequências teloméricas detectaram exclusivamente as regiões cromossômicas terminais de D. seniculus, assim como previamente observado em D. marmoratus e D. melanargyreus. Já em D. soaresi, as sondas teloméricas também resultaram em marcações centroméricas e pericentroméricas, exceto nos pares telocêntricos identificados como 5 e 6. Dentre as três espécies do grupo D. microcephalus aqui viii analisadas, D. decipiens, D. meridianus e D. werneri, algumas diferenças puderam ser notadas. Enquanto D. meridianus e D. werneri apresentaram apenas um par de cromossomos telocêntricos de tamanho mediano, no cariótipo de D. decipiens três pares de cromossomos telocêntricos de tamanho mediano puderam ser observados. D. berthalutzae, espécie considerada do mesmo clado de D. decipiens, também apresenta cariótipo com três pares de telocêntricos de tamanho mediano. Em relação à localização da NOR, os cariótipos de D. decipiens, D. meridianus e D. werneri se assemelham, já que em todos a NOR foi localizada na região terminal do braço longo de cromossomos telocêntricos/subtelocêntricos identificados como 12. A partir de cromossomos telocêntricos microdissecados de D. nanus foi construída uma sonda capaz de identificar o par de cromossomos 15 dessa espécie. A sonda obtida, quando hibridada em cariótipos de outras linhagens de D. nanus e no cariótipo de D. walfordi, também detectou cromossomos telocêntricos de tamanho pequeno, sugerindo a homeologia entre eles. Este é o primeiro estudo que utiliza a técnica de pintura cromossômica para analisar os cromossomos telocêntricos de Dendropsophus e os resultados preliminares aqui apresentados sugerem que essa pode vir a ser uma interessante ferramenta na investigação da evolução cromossômica no gênero / Abstract: The genus Dendropsophus (Anura: Hylidae) comprises 94 neotropical species, from which only 31 were studied cytogenetically. The species of this genus have the same chromosome number (2n=30) but differ on fundamental number and NORs location. Cytogenetic markers, however, are scarce for this genus and a large number of species has not been karyotyped yet. Therefore, it is still not possible to infer about the possible events involved in the karyological divergence in this genus. In order to provide new data for evolutionary karyotype analysis in Dendropsophus, we described cytogenetically two species of D. marmoratus group, D. seniculus and D. soaresi, and one species of D. microcephalus group, D. werneri; we also detailed the karyotypes of two other species of D. microcephalus group, D. decipiens and D. meridianus. Sequences isolated from D. soaresi genome were used for chromosomal localization of the 5S rDNA gene. Probes were also used to observe the chromosomal localization of telomeric sequences in all the species in study. Finally, in an attempt to generate chromosomal probes for future studies of the telocentric chromosomes found in Dendropsophus, chromosome painting experiments were conducted with D. nanus and D. walfordi. Dendropsophus seniculus and D. soaresi had very similar karyotypes, with the NOR located on the long arm of chromosome pair 9. These karyotypes are similar to those of the other three species of D. marmoratus group already karyotyped (D. marmoratus, D. nahdereri and D. melanargyreus), although the karyotype of D. nahdereri differs from the others by presenting the NOR in the short arm of chromosome pair 1. Two types of 5S rDNA sequences were found in D. soaresi. While type I 5S rDNA sequence consists of 512 bp and includes a NTS composed of 390 bp, the NTS of type II 5S rDNA has only 249 bp. Type I 5S rDNA nucleotide sequence is identical to the 5S RNA gene found in Gastrotheca riobambae. When used as a probe, the type I 5S rDNA of D. soaresi was mapped in the long arm of chromosome pair 2 of D. seniculus and D. soaresi. Telomeric sequences used as probes detected chromosomal ends in D. seniculus, as previously observed in D. marmoratus and D. melanargyreus. However, the telomeric probes also resulted in centromeric and pericentromeric signals in the chromosomes of D. soaresi, except the telocentric pairs identified as 5 and 6. Among the three species of the D. microcephalus group analyzed herein, D. decipiens, D. meridianus and D. werneri, some differences could be noted. While D. meridianus and D. werneri had only one pair of telocentric chromosomes of medium size, D. decipiens karyotype had three telocentric pairs. The x species D. berthalutzae, which is included in the same clade of D. decipiens, has also three telocentric pairs of a medium size. The karyotypes of D. decipiens, D. meridianus and D. werneri are also similar with regards to the NOR, which was located terminally in the long arm of a telocentric/subtelocentric chromosome identified as 12. The smallest telocentric chromosomes of D. nanus were microdissected and used to construct a probe, which was able to detect chromosome pair 15 of this species. When this probe was hybridized to the karyotype of different lineages of D. nanus and D. walfordi, a small telocentric chromosome pair was also detected, which suggests their homeology. This is the first work that includes chromosome painting to study the telocentric chromosomes in Dendropsophus and preliminary results presented here suggest that this may be an interesting tool to assess the chromosomal evolution in this genus / Mestrado / Biologia Celular / Mestra em Biologia Celular e Estrutural
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L'invasion péri-nerveuse des carcinomes épidermoïdes cutanés humains / Perineural invasion in human cutaneous squamous cell carcinomaBrugière, Charlotte 04 May 2018 (has links)
Le carcinome épidermoïde cutané (CEC) représente un enjeu important par sa fréquence et sa gravité potentielle.L’agressivité de ce cancer est liée à l’invasion péri-nerveuse (IPN), mode d’envahissement tumoral reconnu comme un facteur de mauvais pronostic.L’objectif de ce travail est de s’intéresser aux mécanismes favorisant l’IPN, en comparant 2 groupes appariés de CEC humains, avec et sans IPN.Pour cela nous avons réalisé une étude de facteurs et récepteurs neurotrophiques, de marqueurs de la transition épithélio-mésenchymateuse (TEM), et de la molécule NCAM1, par analyse immunohistochimique à partir de pièces chirurgicales de CEC et par analyse moléculaire en droplet digital PCR sur des cellules tumorales microdisséquées.L’analyse immunohistochimique a trouvé une forte expression de BDNF, TrkB, p75NGFR, Snail 1 et NCMA1 dans les cellules tumorales péri-nerveuses, contrastant avec une faible expression de ces marqueurs dans les cellules tumorales à distance du nerf. L’E-cadhérine était diminuée dans les cellules tumorales péri-nerveuses.L’analyse moléculaire en ddPCR montrait une diminution d’expression de l’E-cadhérine et une surexpression de BDNF, TrkB, p75NGFR, Snail1, Slug, Zeb2, Twist1 et NCAM1 dans les cellules tumorales péri-nerveuses par rapport aux cellules tumorales distantes du nerf.Nous avons démontré dans ce travail que l’invasion péri-nerveuse dans les CEC humains est liée aux neurotrophines, à la TEM et implique NCAM1. / Cutaneous squamous cell carcinoma (SCC) is an important issue because of its frequency and potential severity.The aggressiveness of this cancer is related to perineural invasion (PNI), a mode of tumor dissemination recognized as a poor prognosis factor.The aim of this work is to study the mechanisms of PNI, comparing 2 matched- groups of human SCC with and without PNI.For this, we studied neurotrophins, epithelial-mesenchymal transition (EMT) markers, and the NCAM1 molecule, by immunohistochemistry analysis on surgical pieces of SCC and by molecular analysis with digital-droplet PCR on laser-microdissected tumor cells.Immunohistochemistry analysis found strong expression of BDNF, TrkB, p75NGFR, Snail 1 and NCMA1 in perineural tumor cells, contrasting with weak expression of these markers in tumor cells distant from the nerves. E-cadherin was decreased in perineural tumor cells.Molecular analysis in ddPCR showed decreased expression for E-cadherin and overexpression of BDNF, TrkB, p75NGFR, Snail1, Slug, Zeb2, Twist1 and NCAM1 in perineural tumor cells compared to tumor cells distant from the nerves.We have demonstrated in this work that PNI in human SCC is linked to neurotrophins and EMT, and involves NCAM1.
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