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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

La dystrophie endothéliale cornéenne de Fuchs sous l'angle de la mitochondrie : marqueur de progression et avenue de traitement

Méthot, Sébastien 22 August 2023 (has links)
Thèse ou mémoire avec insertion d'articles. / L'endothélium cornéen est la couche cellulaire la plus postérieure de la cornée. Elle a pour rôle de maintenir la cornée en déturgescence nécessaire à sa transparence. À cette fin, les cellules endothéliales cornéennes agissent comme une barrière pour limiter l'entrée de liquide et, à l'aide de pompes Na⁺/K⁺ ATPases, expulsent les liquides du stroma cornéen vers la chambre antérieure. La dystrophie endothéliale cornéenne de Fuchs (FECD) est une maladie de la cornée qui compromet le rôle de l'endothélium menant à des pertes de vision. La pathologie est caractérisée par une perte de cellules endothéliales accélérée et la formation d'excroissances de matrice extracellulaire appelées les guttaes. La perte de l'intégrité de l'endothélium cornéen provoque des infiltrations de liquide dans le stroma menant à une perte de la transparence de la cornée. Le seul traitement curatif pour la FECD est la transplantation de cornée pour laquelle la quantité de greffons est limitante. Les causes de la FECD ne sont pas encore bien comprises. Toutefois il existe des évidences d'une implication des mitochondries et du stress oxydatif. Ces deux éléments seraient liés dans un cercle vicieux où les dommages mitochondriaux causés par le stress oxydatif mèneraient à une augmentation de la production d'espèces réactives de l'oxygène. L'effet de ce cercle vicieux sur la fonction mitochondriale et comment cela affecte la progression de FECD reste peu connu et c'est à ce niveau que les travaux de cette thèse sont contributoires. En prenant en compte la démonstration de variation dans la masse mitochondriale entre les cellules endothéliales FECD réalisée précédemment dans notre équipe, nous avons tout d'abord lié la masse mitochondriale à des marqueurs de santé mitochondriale et d'état de la cellule. Ceci a permis de lier ces marqueurs à la progression de la pathologie. En effet, nous avons montré que le statut apoptotique et oxydatif ainsi qu'un niveau de calcium et de potentiel membranaire mitochondrial des cellules de l'endothélium provenant de patients FECD variaient en fonction de leur masse mitochondriale. Nous avons émis l'hypothèse que les variations de masse mitochondriale observées sont liées à des évènements dans la progression de la FECD liée à une surutilisation mitochondriale qu'on a appelé le «burnout mitochondrial». Nous avons ensuite lié la présence des guttae aux différents indicateurs du «burnout mitochondrial». En mesurant l'aire des guttae en conjonction avec les marqueurs de santé mitochondriale et d'état cellulaire, il a été possible de montrer que la présence des guttae est liée à un bilan négatif pour la santé mitochondriale et le statut apoptotique et oxydatif des cellules endothéliales des patients FECD. Nos travaux montrant que l'endommagement des mitochondries par la FECD jouait un rôle central dans la progression de la pathologie nous ont permis de soulever l'hypothèse que l'ajout de mitochondries saines dans les cellules endothéliales ralentirait la progression de la pathologie. Pour tester cette hypothèse, nous avons transplanté des mitochondries via la co-incubation avec des endothélia de patients FECD. Nous avons ensuite évalué l'effet de la transplantation de mitochondries sur les différents marqueurs cellulaires de progression de la FECD. Une amélioration de la santé mitochondriale, autant au niveau du potentiel mitochondrial que du calcium mitochondrial et de la mitophagie, a été observée à la suite de la transplantation. Nous avons également observé une amélioration de l'état cellulaire par la diminution du stress oxydatif et une perte du statut apoptotique pour la majorité des cellules endothéliales. Les travaux de cette thèse mettent en lumière une chronologie des évènements de la FECD liés à la progression de la pathologie ainsi que l'apparition de guttae. Ces travaux présentent aussi une nouvelle avenue de traitement pour la FECD en utilisant la transplantation mitochondriale. Cela pourrait permettre de diminuer, voire d'abolir, le besoin de greffons de cornée pour traiter la pathologie. / The corneal endothelium is the most posterior cell layer of the cornea. Its role is to maintain the cornea in deturgescence which is necessary for its transparency. To this end, corneal endothelial cells act as a barrier to limit fluid entry and, with the help of Na⁺/K⁺ ATPase pumps, expel fluids from the corneal stroma to the anterior chamber. Fuchs corneal endothelial dystrophy (FECD) is a corneal disease that compromises the role of the endothelium leading to loss of vision. The pathology is characterized by accelerate dendothelial cell loss and the formation of extracellular matrix growths called guttae. The loss of integrity of the corneal endothelium causes fluid infiltration into the stroma leading to a loss of corneal transparency. The only curative treatment for FECD is corneal transplantation for which the quantity of grafts is limited. The causes of FECD are not well understood yet, however there is evidence of the involvement of mitochondria and oxidative stress. These two elements appear to be linked in a vicious circle where mitochondrial damage caused by oxidative stress leads to an increase in the production of reactive oxygen species. The effect of this vicious circle on mitochondrial function and how it affects the progression of FECD remains unknown and it is at this level that the work of this thesis is contributory. Considering the demonstration of variation in mitochondrial mass between FECD endothelial cells made previously in our team, we first linked mitochondrial mass to markers of mitochondrial health and cell status. This made it possible to link these markers to the progression of the pathology. Indeed, we showed that the apoptotic and oxidative status as well as a level of calcium and mitochondrial potential of endothelial cells from FECD patients varied according to their mitochondrial mass. We hypothesized that the observed mitochondrial mass variations are related to events in the progression of FECD related to mitochondrial overuse that we have named "mitochondrial burnout". Then, we linked the presence of guttae to different indicators of "mitochondrial burnout". By measuring the area of guttae in conjunction with markers of mitochondrial health and cellular state, it was possible to show that the presence of guttae is linked to a negative outcome for mitochondrial health and the apoptotic and oxidative status of cells. endothelial disease of FECD patients. Our work shows that the damage of mitochondria by FECD plays a central role in the progression of the pathology, we raised the hypothesis that the addition of healthy mitochondria to endothelial cells would slow down the progression of the pathology. To test this hypothesis, we transplanted mitochondria via co-incubation to FECD patient endothelium. We then evaluated the effect of mitochondria transplantation on the different cellular markers of FECD progression. An improvement in mitochondrial health, both in terms of mitochondrial potential and mitochondrial calcium and mitophagy, was observed following transplantation. We also observed an improvement in the cellular state by the reduction of oxidative stress and a loss of apoptotic status for a majority of endothelial cells. The work of this thesis sheds light on a chronology of FECD events related to the progression of the pathology as well as the appearance of guttae. This work also presents a new avenue of treatment for FECD using mitochondrial transplantation. This could reduce or even eliminate the need for corneal grafts to treat the pathology.
12

Influência de implantes pós-exodônticos com diferentes configurações sobre os tecidos peri-implantares : estudo experimental em cães /

Caneva, Marco. January 2011 (has links)
Orientador: Daniele Botticelli / Banca: Wilson Roberto Poi / Banca: Idelmo Rangel Garcia Júnior / Banca: Luiz Antônio Salata / Banca: Thais da Silveira Rodrigues / Resumo: Objetivo: avaliar a influência da instalação de implantes em alvéolos imediatamente após a extração do elemento dental na regeneração dos tecidos peri-implantares com implantes de diferentes configurações Material e métodos: Nos alvéolos distais dos quartos pré-molares mandibulares de cães, imediatamente após as extrações das raízes dentais, foram instalados implantes cilíndricos com 3,3 mm de diâmetro (grupo controle) e implantes cônicos com 5,0 mm de diâmetro (grupo teste). Foram avaliados histologicamente a regeneração dos tecidos duros e moles peri-implantares após 4 meses do procedimento cirúrgico. Resultados: Todos os implantes apresentaram-se osseointegrados ao tecido ósseo maduro mineralizado. A crista óssea alveolar sofreu reabsorção tanto no grupo teste como controle. A superfície óssea vestibular dos implantes do grupo teste (cônico; 3,6 mm) apresentou maior grau de reabsorção em comparação ao grupo controle (cilíndrico; 1,6 mm). As dimensões dos tecidos moles apresentaram-se semelhantes em ambos os grupos. No entanto, em relação ao ombro do implante, a mucosa peri-implantar localizou-se mais apicalmente no grupo teste em relação ao grupo controle. Conclusão: Este estudo confirmou que a distância entre a superfície do implante e o contorno externo da crista óssea alveolar vestibular influenciou no grau de reabsorção da tábua óssea vestibular. Conseqüentemente, em relação ao ombro do implante, a mucosa peri-implantar será estabelecida em um nível mais apical, se a distância entre a superfície do implante e o contorno externo da crista óssea alveolar for menor / Abstract: Aim: the aim of the present experiment was to study the influence of implant installation into sockets immediately after tooth extraction on the healing periimplant tissues with implants of various configurations. Material & methods: Transmucosal cylindrical 3.3mm in diameter implants in the control sites, and conical 5.0mm in diameter in the test sites, were installed into the distal socket of the forth mandibular premolars in dogs immediately after tooth extraction. After 4 months, the hard and soft tissue healing was evaluated histologically. Results: All implants were integrated in mineralized mature bone. Both at the test and control sites, the alveolar crest underwent resorption. The buccal bony surface at the implant of the test sites (conical; 3.6mm) was more resorbed compared to the control sites (cylindrical; 1.6mm). The soft tissue dimensions were similar in both groups. However, in relation to the implant shoulder, the periimplant mucosa was located more apically at the test compared to the control sites. Conclusion:The present study confirmed that the distance between the implant surface and the outer contour of the buccal alveolar bony crest influenced the degree of resorption of the buccal bone plate. Consequently, in relation to the implant shoulder, the peri-implant mucosa will be established at a more apical level if the distance between the implant surface and the outer contour of the alveolar crest is small / Doutor
13

Genetic improvement of xylanase.

January 2004 (has links)
Yuan Zhao. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 89-96). / Abstracts in English and Chinese. / Abstract (English) --- p.i / Abstract (Chinese) --- p.iii / Acknowledgements --- p.iv / Declaration --- p.v / Abbreviations --- p.vi / Table of Contents --- p.viii / List of Tables --- p.xii / List of Figures --- p.xiii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Lignocelluloses --- p.2 / Chapter 1.1.1 --- component of lignocellulose --- p.2 / Chapter 1.1.2 --- Xylans --- p.3 / Chapter 1.2 --- Degradation of lignocellulose --- p.9 / Chapter 1.3 --- "Endo-β-1,4- xylanase" --- p.12 / Chapter 1.3.1 --- Structure of xylanase --- p.12 / Chapter 1.3.2 --- Mode of action --- p.17 / Chapter 1.3.3 --- Appications of xylanase --- p.20 / Chapter 1.4 --- Aims of my study --- p.24 / Chapter Chapter 2 --- Materials and Methods --- p.25 / Chapter 2.1 --- Cloning of xylanase genes --- p.26 / Chapter 2.1.1 --- Materials --- p.26 / Chapter 2.1.1.1 --- Bacterial and fungal strains --- p.26 / Chapter 2.1.1.2 --- Growth media --- p.26 / Chapter 2.1.1.3 --- Vector --- p.26 / Chapter 2.1.1.4 --- Reagents for agarose gel electrophoresis --- p.27 / Chapter 2.1.1.5 --- Reagents for preparation of competent cells --- p.27 / Chapter 2.1.2 --- Methods --- p.29 / Chapter 2.1.2.1 --- Isolation of chromosomal DNA --- p.29 / Chapter 2.1.2.2 --- Amplification of exons of xylanase genes --- p.29 / Chapter 2.1.2.3 --- Agarose gel electrophoresis of DNA --- p.37 / Chapter 2.1.2.4 --- DNA recovery from agarose gel --- p.37 / Chapter 2.1.2.5 --- Assemble and amplify the full length genes --- p.38 / Chapter 2.1.2.6 --- Restriction endonuclease digestion --- p.39 / Chapter 2.1.2.7 --- Ligation of purified DNA fragment into vector --- p.39 / Chapter 2.1.2.8 --- Transformation --- p.40 / Chapter 2.1.2.9 --- Methods for making competent cells --- p.40 / Chapter 2.1.2.10 --- Plasmid DNA preparation --- p.40 / Chapter 2.1.2.11 --- DNA sequencing --- p.41 / Chapter 2.2 --- Mutagenesis of xylanase --- p.43 / Chapter 2.2.1 --- Amplification of xylanases genes --- p.47 / Chapter 2.2.2 --- DNA random mutagenesis --- p.48 / Chapter 2.2.2.1 --- DNase digestion --- p.48 / Chapter 2.2.2.2 --- Reassembly of DNA fragments --- p.48 / Chapter 2.2.2.3 --- Amplification of full-length genes --- p.48 / Chapter 2.2.2.4 --- Construction of library --- p.49 / Chapter 2.2.3 --- Screening of mutants --- p.49 / Chapter 2.2.3.1 --- Preparation of RBB-xylan --- p.49 / Chapter 2.2.3.2 --- Plate assay for screening of mutants --- p.50 / Chapter 2.3 --- Expression of xylanase genes --- p.51 / Chapter 2.4 --- Enzyme assays --- p.52 / Chapter 2.4.1 --- Xylanase assay with RBB-xylan --- p.52 / Chapter 2.4.2 --- Xylanase assay with DNS-method --- p.52 / Chapter 2.4.2.1 --- Reagents --- p.53 / Chapter 2.4.2.2 --- Xylose standard curve --- p.53 / Chapter 2.4.2. 3 --- Activity assay --- p.54 / Chapter 2.4.2. 4 --- Thermostability assay --- p.54 / Chapter Chapter 3 --- Results --- p.55 / Chapter 3.1 --- Cloning of xylanase genes --- p.56 / Chapter 3.2 --- Mutagenesis of xylanase --- p.59 / Chapter 3.2.1 --- DNA random mutagenesis --- p.59 / Chapter 3.2.2 --- Screening of mutants --- p.67 / Chapter 3.3 --- Enzyme assays --- p.69 / Chapter Chapter 4 --- Discussions --- p.76 / Chapter 4.1 --- Gene shuffling --- p.77 / Chapter 4.2 --- Screening method and activity assay --- p.78 / Chapter 4.3 --- Sequence analysis --- p.80 / Chapter 4.4 --- Future work --- p.88 / Bibliography --- p.89
14

Breeding of better [beta]-xylulokinase. / CUHK electronic theses & dissertations collection

January 2004 (has links)
Bu Su. / "July 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 139-158). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
15

Breeding of better [beta]-D-xylosidase. / CUHK electronic theses & dissertations collection / Digital dissertation consortium

January 2003 (has links)
Peijun Zuo. / "November 2003." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (p. 188-212). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
16

Avfall från dricksvattenkvalitetslaboratorium : En studie om avfallsklassning och hantering av m-Endo agar LES vid Stockholm Vatten.

Agnemo, Elin January 2014 (has links)
The purpose of the study was to determine how the waste from m-Endo agar LES (LesEndo) should be categorized and managed, due to its content of the carcinogenic substance basic red 9 in basic fuchsine. The information was obtained by studying legislation and a laboratory practical was performed to verify, if basic fuchsine could remain in LesEndo agar after being heated. This was important to know for the further interpretation how to categorize and manage the waste according to the legislation. LesEndo agar was autoclaved at 121 °C for 15 and 30 minutes. E. coli and coliform bacteria was put to grow on the LesEndo agar. The results from the study showed that all replicas had coliform colonies, which appeared with a metallic fuchsine-sheen. This verified that basic fuchsine was unchanged and that there was no significant difference in growth between replicas with heated agar and the control. The total concentration of basic fuchsine in LesEndo agar was 0.08%. To be categorized as hazardous waste the threshold value for basic red 9 is 0.1%. According to a strict interpretation of the legislation, waste from used LesEndo agar should not be categorized and managed as hazardous waste. However, evaporation has to be taken into consideration and the concentration may be above 0.1%. Therefore my evaluation is that waste from used LesEndo agar should be categorized and managed as hazardous waste to protect humans and the environment from being harmed.
17

FLUTUAÇÕES DO BUTOH NO CORPO DO ARTISTA QUE DANÇA: POÉTICAS DA MESTIÇAGEM

Martins, Simone 18 June 2013 (has links)
Submitted by Diana Alves (ppgdancaufba.adm@gmail.com) on 2013-06-18T12:10:54Z No. of bitstreams: 1 Dissertação- 01-04-2013-PDF COM IMAGENS (1).pdf: 1608877 bytes, checksum: f71f67d6261b89956f2bc3242ccf7d7e (MD5) / Approved for entry into archive by Alda Lima da Silva(sivalda@ufba.br) on 2013-06-18T19:44:00Z (GMT) No. of bitstreams: 1 Dissertação- 01-04-2013-PDF COM IMAGENS (1).pdf: 1608877 bytes, checksum: f71f67d6261b89956f2bc3242ccf7d7e (MD5) / Made available in DSpace on 2013-06-18T19:44:00Z (GMT). No. of bitstreams: 1 Dissertação- 01-04-2013-PDF COM IMAGENS (1).pdf: 1608877 bytes, checksum: f71f67d6261b89956f2bc3242ccf7d7e (MD5) / FAPESB / Esta dissertação pretende estabelecer uma ponte flutuante para dar início a uma viajem com trânsitos, deslocamentos, migrações que exploram as misturas entre campos de conhecimento, entre linguagens, entre textos, entre danças. Este estudo tratará as danças e os corpos que dançam como objetos flutuantes percebendo-os a partir de seu movimento ondulatório, em constante vibração, propagação, perturbação, mistura e dissipação. Elegendo como foco da investigação os estados de contaminação, optamos por um diálogo-correspondência, com dois artistas japoneses, que em seus percursos de vida, deixam marcas de seus passos no Brasil, Takao Kusuno (1945-2001) e Tadashi Endo (1947). Escavando o corpo do artista da dança, atraídos pelo Ankoku Butoh como alvo de indagações, experimentações e criações. Entendendo a Dança do Butoh na linha de fuga deleuzeana (DELEUZE, 1996), de sua filosofia tomamos a visão rizomática e desvios. Os temas que abordaremos partem da reflexão relativa aos processos de mestiçagem da cultura nos valendo das ideias do filósofo Michel Serres (SERRES,1993). Mestiçagem que acreditamos ocorrer no corpo do artista que entra em contato com uma dança que não conhece, passando a confrontar-se com processos de desestabilização, de atualização e incorporação da informação estrangeira. Segundo a visão da Teoria Geral de Sistemas e de acordo com Jorge de Albuquerque Vieira, todos os sistemas do universo evoluem num estado de contínua flutuação. Estas flutuações se dão por meio de crises e perturbações em etapas sucessivas tal qual na noção de auto organização sistêmica de Ilya Prigogine (PRIGOGINE & STENGERS, 1984, ) que trata da ordem a partir das flutuações, desvios que implicam em sequências de instabilidades. Nos aproveitamos do intercruzamento da dança com as ciências cognitivas com o conceito de mediação do corpo mídia (Greiner & Katz, 2001) dos fluxos de informação, observamos os processos de ‘’embodiment/corporalização’’ (Queiroz, 2004, 2009) e investigamos a capacidade de um sistema (butoh), produzir efeitos e criar condições, para que estes efeitos se estabilizem e inventem novas configurações. Neste estudo propusemos uma pesquisa de campo intitulada Experiências Flutuantes do Butoh (Brasil-Peru). As experiências se entrecruzam com a elaboração da dissertação tornando-se uma ‘’zona de flutuação’’ onde investigamos como as informações se propagam, modificam, passam por adaptações, se estabelecem de imediato em novas soluções ou ocorrem em etapas crísicas, como sugere o conceito do Evolon (MENDE, apud VIEIRA, 2007) e corpo crise (Greiner, 2010). Nesta escrita-dança–crise experimentamos os processos de mestiçagem no corpo do artista que dança afetado pelo butoh, constituindo explorações em campos interdisciplinares. / PROGRAMA DE PÓS GRADUAÇÃO EM DANÇA- ESCOLA DE DANÇA
18

Avaliações biomecânicas e biológicas relacionadas às próteses implanto-suportadas e aos implantes osseointegrados /

Barão, Valentim Adelino Ricardo. January 2011 (has links)
Orientador: Wirley Gonçalves Assunção / Banca: Debora Barros Barbosa / Banca: Paulo Henrique dos Santos / Banca: Cortino Sukotjo / Banca: Maria da Glória Chiarello de Mattos / Resumo: Objetivos: (1) Investigar o papel de diferentes níveis de pH da saliva artificial (3; 6,5 e 9) no comportamento corrosivo do titânio comercialmente puro (cp-Ti) e da liga Ti-6Al-4V (Capítulo 1); (2) Avaliar a influência do processo de corrosão na afinidade do lipopolissacarídeo (LPS) de Escherichia coli para o cp-Ti e o Ti-6Al-4V (Capítulo 2); (3) Investigar a natureza tribocorrosiva do titânio em saliva artificial em presença de LPS (Capítulo 3); (4) Comparar o efeito de diferentes designs de overdentures implanto-retidas e prótese total fixa implanto-suportada na distribuição de tensões em mandíbula edêntula pelo método de elementos finitos tridimensional (Capítulo 4). Materiais e métodos: Testes eletroquímicos como potencial de circuito aberto, espectroscopia de impedância eletroquímica, e teste potenciodinâmico foram conduzidos. Para o teste de afinidade ao LPS, os espécimes foram tratados com LPS (1,5; 15 e 150 μg/ml) durante 24 horas para avaliar a aderência de LPS. Os discos foram transferidos a cada 24 horas para solução fresca de água livre de LPS até completar 72 horas, para investigar a liberação de LPS. No teste de tribocorrosão, o pH da saliva (6,5), a concentração de LPS (0, 0,15, 15 and 150 μg/ml), a duração do deslizamento (2000 ciclos), freqüência (1,2 Hz) e carga (20 N) foram usados para mimetizar o processo mastigatório. Finalmente, modelos tridimensionais de uma mandíbula edêntula foram construídos. No grupo OR a mandíbula foi restaurada com overdenture retida por implantes não esplitados com sistema de retenção O'ring; nos grupos BC-C e BC as mandíbulas foram restauradas com overdentures retidas por implantes esplintados com sistema de retenção barra-clipe associado ou não a cantilevers distais... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Objectives: (1) To investigate the role of different levels of pH of artificial saliva (pHs 3, 6.5 and 9) under simulated oral environment on the corrosion behavior of commercially-pure titanium (cp-Ti) and Ti-6Al-4V alloy (Chapter 1); (2) To assess the influence of corrosion process on Escherichia coli lipopolysaccharide (LPS) affinity for cp-Ti and Ti-6Al-4V alloy (Chapter 2); (3) To evaluate the tribocorrosive (corrosion/wear) nature of titanium in artificial saliva (pH 6.5) with LPS (Chapter 3); and (4) To compare the effect of different designs of implant-retained overdentures and fixed full-arch implant-supported prosthesis on stress distribution in edentulous mandible by using a three-dimensional finite element analysis. Materials and methods: Standard electrochemical tests, such as open circuit potential, electrochemical impedance spectroscopy, and potentiodynamic tests were conducted in a controlled environment. For LPS affinity test, specimens were treated with LPS (1.5, 15 and 150 μg/ml) for 24 hours to evaluated LPS adherence. Discs were then transferred every 24 hours to fresh LPS-free water, up to 72 hours, to investigate LPS elution. In the tribocorrosion test, the pH of saliva (6.5); LPS concentration (0, 0.15, 15 and 150 μg/ml), sliding duration (2000 cycles), frequency (1.2Hz) and load (20 N) parameters mimicked the mastication process. Finally, tridimensional models of an edentulous mandible were constructed. In the OR group, the mandible was restored with an overdenture retained by unsplinted implants with O'ring attachment; in the BC-C and BC groups, the mandibles were restored with overdentures retained by splinted implants with bar-clip anchor associated or not with distally placed cantilevers, respectively; in the FD group, the mandible was restored with a fixed full-arch implant-supported prosthesis... (Complete abstract click electronic access below) / Doutor
19

Avaliação da prevalência das doenças peri-implantares e do sucesso e sobrevivência de implantes osseointegrados com 8 a 10 anos de função /

Marcantonio, Claudio. January 2014 (has links)
Orientador: Daniela Leal Zandim Barcelos / Co-orientador: / Banca: José Eduardo Cezar Sampaio / Banca: Francisco de Assis Molo Junior / Banca: Rafael Silveira Faeda / Banca: Waldyr Antonio Jorge / Resumo: O propósito deste estudo retrospectivo foi verificar as taxas de sucesso e sobrevivência de implantes osseointegrados no longo prazo, assim como determinar a prevalência de doenças peri-implantares e identificar possíveis fatores de risco associados à ocorrência da peri-implantite. A amostra foi constituída de 50 pacientes parcialmente desdentados que realizaram reabilitações sobre implantes osseointegrados no período de 2003 a 2005. As avaliações incluíram a coleta de informações demográficas, sistêmicas e comportamentais, além de exames clínicos e radiográficos para avaliação da condição periodontal e peri-implantar. Uma análise multivariada foi adotada para identificar possíveis preditores de risco para a periimplantite. Um total de 211 implantes foram instalados nestes pacientes. Cinco implantes foram perdidos e 9 implantes encontravam-se submersos, ou seja, sem função. Assim, 197 implantes em 48 pacientes foram avaliados clinicamente. A prevalência de mucosite foi de 77,1% a nível de paciente e 52,3% a nível de implante. A peri-implantite foi diagnosticada em 25 implantes em 14 pacientes. As taxas de sucesso e de sobrevivência encontradas foram de 82% e de 97,6%, respectivamente. A presença de osteoporose (OR = 2,87) e a presença de sangramento à sondagem (SS) de boca toda ≥ 30% dos sítios (OR = 8,03) foram variáveis relacionadas ao indivíduo significativamente associadas com maior ocorrência de periimplantite. A presença de placa visível (OR = 4,45) e a presença de sítios com profundidade de sondagem (PS) ≥ 4 mm (OR = 4,47) foram variáveis relacionadas ao implante significativamente associadas com maior ocorrência de peri-implantite. Apesar da alta taxa de sobrevivência no longo prazo, foi observada uma alta prevalência de mucosite e a peri-implantite foi diagnosticada em 12,7% dos implantes e 29,2% dos pacientes avaliados...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract:The aim of the present study was to verify the long-term success and survival rates of osseointegrated dental implants, as well to determine the prevalence of peri-implant disease, and to identify potential risk factors associated to the occurrence of peri-implantitis. The sample was comprised of 50 patients who had their implant-supported rehabilitation concluded between the years of 2003 and 2005. Evaluations included the gathering of demographic, systemic and behavioral information, as well as radiographic and clinical records for the assessment of periodontal and peri-implant conditions. Multivariate analysis was employed to identify potential risk factors related to the occurrence of peri-implantitis. A total of 211 implants were installed, out of which 5 were lost and 9 were submerged, that is, nonfunctioning. Thus, 197 implants in 48 patients were clinically evaluated. The presence of osteoporosis (OR = 2,87) and the presence of full-mouth BOP scores ≥ 30% of sites (OR = 8,03) were variables significantly associated with a higher occurrence of peri-implantitis, among the subjects. At the implant level, the presence of visible plaque (OR = 4.45) and the presence of sites with probing depth (PD) ≥ 4 mm (OR = 4.47) were variables significantly associated with a higher occurrence of peri-implantitis. Mucositis prevalence was 77.1% and 52.3%, at subject and implant level, respectively. Periimplantitis was diagnosed in 25 implants (12.7%) and 14 patients (29.2%). Success and survival rates were 82% and 97.6%, respectively. Our results suggest that subjects with osteoporosis and with full-mouth BOP scores ≥ 30% of the sites, as well as implants with visible plaque and sites with PD ≥ 4 mm, are more susceptible to peri-implantitis. / Doutor
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Avaliação da temperatura gerada e do tempo gasto durante o preparo do tecido ósseo com a utilização de brocas de diferentes sistemas de implantes /

Faria, Renata. January 2005 (has links)
Orientador: Fernando Eidi Takahashi / Banca: Francisco Fernando Todescan / Banca: Marco Antonio Bottino / Resumo: Este estudo teve como objetivo avaliar a temperatura gerada e o tempo gasto durante o preparo do tecido ósseo comparando brocas de três sistemas de implantes: Conexão, Nobel e 3i. Utilizaram-se amostras de osso cortical de fêmur bovino e um aparato especialmente idealizado para se padronizar os procedimentos nos ensaios. As perfurações foram feitas com brocas de 2,0 e 3,0mm de diâmetro, até a profundidade de 13mm, a uma velocidade de 1500 rpm com pressão intermitente de 2kg, sob constante irrigação de solução de soro fisiológico 0,9% à temperatura ambiente (24 ±1o C). Os corpos-de-prova foram mantidos imersos em água a 36±10 C durante as perfurações. As temperaturas foram medidas com termopares inseridos no osso a 1mm da perfuração, em profundidades de 5 e 13mm e registradas com o auxílio de um coletor de dados (ADS 2000 IP - Links, Brasil) conectado a um computador. Os dados de temperatura foram analisados pelo teste RM ANOVA (3 fatores), considerando um fatorial tipo 2 x 3 x 2 (diâmetro x broca x profundidade). A profundidade foi o fator repetido. Os dados do tempo foram analisados pelo teste ANOVA (2 fatores), considerando um fatorial de 2 x 3 (diâmetro x broca). As análises foram seguidas pelo teste de Tukey (5%). Com relação à temperatura, os resultados indicaram que a melhor condição experimental foi obtida para a broca Conexão de diâmetro 2mm na profundidade de 5mm (36,10±0,52oC) e a condição menos favorável foi para a broca Nobel de diâmetro 2mm na profundidade de 13mm (38,84±1,15oC). Com relação ao tempo a melhor condição experimental foi obtida para a broca Nobel de diâmetro 3mm (6,80±0,79s) e a condição menos favorável foi para a broca 3i de diâmetro 2mm (99,40±18,70s). O efeito diâmetro foi significante podendo-se afirmar que, independentemente do tipo de broca, para 2mm (59,13 ±31,10s) supera 3mm (11,67±4,89s). Concluiu-se ... / Abstract: The aim of this study was to evaluate the temperature rise and the amount of time to prepare the bone tissue with three types of implant drills: Conexão, Nobel and 3i. Specimens of bovine cortical femoral bone (blocks) and a special set-up were made for the test. Holes were made with 2 and 3 mm diameter drills, at a speed of 1.500 rpm with 2kg intermitent loading , under constant irrigation with saline solution (0,9% NaCl), at room temperature (24°C±1°C). The blocks were kept in 36°C±1°C water bath during drilling. The temperatures rises were measured with thermocouples placed at 5 and 13mm depth and 1mm distant from the holes and recorded with the aid of a data collector (ADS 2000 IP-Lynx, Brazil) operated by a personal computer. Data of temperature were subjected to Repeated Measures Anova (3 way), considering a factorial type of 2 x 3 x 2 (diameter X drill x depthness). The depthness was the repeated factor, α=5%. The time data were analysed by using RM Anova (2 way), considering a factorial type of 2 x 3 (diameter x drill) and post hoc pairwise comparisons using Tukey test, α = 5%. The results related to temperature showed that the best condition was obtained for the 2mm Conexão drill at 5mm depthness. (36,10±0,52°C) and the 2mm diameter Nobel drill had the least favorable scenary at a depthness of 13mm (38,84±1, 15°C) . With relation to time the best experimental condition was obtained to the 3mm Nobel drill (6,8±0,79s) and the least favorable was to the 2mm 3i drill (99,4±18,70s). The diameter effect was statistically significant, which means that no matter the type of drill, the 2mm diameter (59,13±31,10s) is higher than the 3mm one (11,67±4,89s). It was concluded that the highest values of temperature were obtained at 13mm depthness, regardless the type of drill. The increase in diameter leaded to a decrease in temperature for 3i and Nobel drills and a rise of ... / Mestre

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