Thesis (Ph. D.)--University of Missouri--Columbia, 2004. / Typescript. Vita. Includes bibliographical references. Also issued on the Internet.

Thesis (Ph. D.)--University of Missouri--Columbia, 2004. / "July 2004." Typescript. Vita. Includes bibliographical references. Also issued on the Internet.

Orientador: Célia Marisa Rizzatti Barbosa / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-18T16:04:07Z (GMT). No. of bitstreams: 1 FariasNeto_Arcelino_D.pdf: 1895628 bytes, checksum: 3d9e789620307fdbeaffe939bf75437e (MD5) Previous issue date: 2011 / Resumo: A cartilagem articular do côndilo mandibular é responsável pelo crescimento ósseo endocondral durante o desenvolvimento mandibular. Ela depende do funcionamento adequado da articulação temporomandibular (ATM) para sua diferenciação e maturação. Trabalhos demonstram que a manipulação funcional da mandíbula foi capaz de alterar a dinâmica fisiológica dessa cartilagem. Nesse sentido, a protrusão diminuiria a ação de cargas sobre o côndilo mandibular, estimulando o crescimento endocondral, e de forma inversa, a retrusão aumentaria a pressão sobre a cartilagem, inibindo o crescimento. Essas técnicas têm sido utilizadas com relativo sucesso na ortopedia facial com o intuito de corrigir discrepâncias maxilo-mandibulares. Entretanto, alguns quadros patológicos presentes nas ATMs podem alterar o seu desenvolvimento normal. Um dos fatores etiológicos que pode ser associado à presença de alterações no côndilo mandibular é a oclusão dental. A hipótese formulada é de que a presença de instabilidade ortopédica causada por um fator oclusal durante a fase de desenvolvimento pode levar à deficiência do crescimento mandibular e alterações intra-articulares. Assim, este trabalho teve por objetivo avaliar, em modelo animal, alterações da oclusão dental sobre o crescimento mandibular e tecidos intra-articulares. O estudo foi randomizado e cego. Foram utilizadas 40 ratas Wistar com 5 semanas de idade divididas aleatoriamente em 4 grupos com o mesmo número de animais: controle, com interferência oclusal, com ausência dos molares inferiores unilateral e com ausência dos molares inferiores bilateral. Os animais foram acompanhados por 8 semanas, período que correspondeu a sua fase de maturação óssea. Após esse período, os animais foram sacrificados e realizou-se tomografia computadorizada de feixe cônico (Cone beam) de suas cabeças para construção de protótipos de biomodelos, sobre os quais foram mensurados o comprimento da mandíbula, a altura do ramo mandibular e distância intercondilar. Em seguida, as articulações temporomandibulares foram cuidadosamente preparadas para análise imunohistoquímica dos níveis de colágeno tipo II, Fator de Crescimento Endotelial Vascular, e Interleucina 1? na cartilagem condilar. Os dados foram submetidos a análise estatística através do Software SPSS versão 17.0. As médias entre os grupos foram comparadas através do One-way Anova, enquanto as diferenças entre os lados da mandíbula foram avaliadas através do teste t de Student (?=0.05). A partir da análise dos resultados, observou-se que alterações oclusais podem afetar o desenvolvimento do osso mandibular, bem como alterar a expressão de Colágeno tipo II, Fator de Crescimento Endotelial Vascular e Interleucina 1? na cartilagem condilar. Diante do exposto, conclui-se que a oclusão dentária é capaz de interferir na dinâmica dos tecidos intra-articulares, sendo um fator importante durante o desenvolvimento craniofacial / Abstract: The condylar cartilage regulates the endochondral ossification during mandibular development. Mechanical stimulus in the temporomandibular joint (TMJ) plays an important role in cell proliferation and differentiation of mandibular condyle. Studies have shown that functional mandibular displacement can affect TMJ cartilage dynamics. Mandibular advancement induces profound metabolic changes in the condyle and enhances growth. In contrast, mandibular retraction reduces growth. The overall picture emerging from the data is that unloading of the condyle increases growth, while loading reduces it. Therefore, dental occlusion could be one of the factors associated with the alteration of the TMJ growth. The hypothesis is that orthopedic instability caused by occlusal factors present during TMJ development can affect mandibular growth and intra-articular tissue. Thus, the purpose of this study was to evaluate the influence of dental occlusion on mandibular growth and intra-articular tissue in Wistar rats. The study was randomized and blinded. Forty 5 weeks old female Wistar rats composed the sample. The animals were randomly allocated to four groups with the same number of rats: (1) control, (2) occlusal appliance for functional posterior displacement of the mandible, (3) unilateral mandibular tooth extraction, (4) bilateral mandibular tooth extraction. The rats were sacrificed after 8 weeks, when they had achieved skeletal maturity. Immediately after death, the heads were fixed in 10% paraformaldehyde, and cone beam CT scan images were taken using the Classic I-CAT (Imaging Sciences International, Hatfield, PA, USA). The 3-dimensional images of rats' skulls were exported in multifile Digital Imaging and Communications in Medicine (DICOM) format, and acrylic rapid-prototyped templates of the mandibles were constructed for measurement of mandibular growth. Immunostaining was used for the detection of type II collagen, vascular endothelial growth factor (VEGF) and interleukin-1?. The data were processed with SPSS software (V 17.0 for Windows, SPSS Inc, Chicago, IL, USA). Differences among the groups were analyzed by one-way ANOVA (Tukey test as post-hoc test), while differences between sides were analyzed by non-paired Student's t test. Shapiro-Wilk and Levene tests were used to observe normality and variance homogeneity, respectively. Confidence level was set at 5%. The results of this study showed that dental occlusion is an important factor for the integrity of intra-articular tissues and to the healthy craniofacial development, emphasizing the importance of early treatment to normalize occlusion and create appropriate conditions for normal craniofacial development / Doutorado / Protese Dental / Doutor em Clínica Odontológica

O tratamento das lesões condrais e osteocondrais do joelho em pacientes jovens ainda permanece um desafio para os médicos ortopedistas. As técnicas de reparo destas lesões atualmente disponíveis no Brasil, como desbridamento, microfraturas e transplante osteocondral autólogo são insuficientes nos tratamentos das lesões condrais e osteocondrais maiores do que 4 cm2. O transplante osteocondral homólogo a fresco (TOF) na articulação do joelho vem sendo usado em outros países com excelentes resultados. Até o presente momento não existem relatos da utilização desta técnica no Brasil, fato que dificulta o tratamento de pacientes jovens ativos que necessitam de reparo biológico. Foram incluídos neste estudo oito pacientes de 15 a 45 anos portadores de lesões osteocondrais maiores que 4 cm2. Os enxertos a fresco foram obtidos de doadores de órgãos, sendo a articulação do joelho captada sem violação da cápsula articular e transportada ao Banco de Tecidos para processamento. O pareamento doador e receptor foi realizado conforme o tamanho, a localização e a prioridade em lista de espera de acordo com os tecidos captados, sendo os mesmos armazenados no meio de preservação Ham F-12 - GIBCO com glutamax (Invitrogen, Life Technologies, Estados Unidos) e com antibióticos. O procedimento cirúrgico foi realizado pelas técnicas de cilindro osteocondral e de superfície, sendo fixados quando necessário. Os pacientes foram avaliados através dos questionários de IKDC objetivo, IKDC subjetivo, KOOS e índice de Merle D\'Aubigne e Postel modificado. Foram realizados oito TOFs de março a outubro de 2012. A média de idade dos pacientes transplantados foi de 30,1 anos (17- 44 anos) e a média da área transplantada foi de 10,6 cm2 (4,6 - 22,4 cm2). O intervalo médio em dias entre captação e transplante foi de 15,3 (14 - 16 dias) e o número médio de cirurgias prévias ao TOF foi de 2 cirurgias (0-4 cirurgias). A pontuação na escala de IKDC objetiva no pré-operatório foi B em 12%, C em 25% e D em 63% dos pacientes; e 12% A e 88% B aos 18 meses de pós-operatório. A média da pontuação da escala IKDC subjetiva pré-operatória foi de 31,99 ± 13,4 e de 81,84 ± 9,25 em 18 meses de pós-operatório, e da escala KOOS pré-operatória foi de 46,8 ± 20,9 e de 89,58 ± 7,06 em 18 meses de pós-operatório, com melhora significativa ao longo do tempo (p < 0,01) pela análise da variância. A média da pontuação pelo índice de Merle D\'Aubigne e Postel modificado foi de 8,75 ± 2,25 no pré-operatório e de 16,75 ± 2,19 em 18 meses de pós-operatório. O resultado do teste de Friedman para amostras não-paramétricas demonstrou melhora significativa ao longo do tempo (p < 0,01). A padronização da captação, processamento e transplante de enxertos osteocondrais a fresco na articulação do joelho depende de um banco de tecidos altamente especializado e leva a excelentes resultados no tratamento de lesões osteocondrais grandes, sendo atualmente uma boa alternativa de tratamento biológico para pacientes jovens no Brasil / Treatment of chondral and osteochondral lesions of the knee in young patients is still a challenge for Orthopedic Surgeons. The techniques available nowadays in Brazil, as debridement, microfracture and autologous osteochondral transplantation are insufficient for the treatment of chondral and osteochondral lesions larger than 4 cm2. Fresh osteochondral allografts on the knee joint have been used in other countries with great success. Until the present days there are no reports of the utilization of this technique in Brazil, a fact that creates boundaries for the treatment of young active patients that need cartilage repair treatment. Eight patients with age ranging from 15 to 45 years old and osteochondral lesions larger than 4 cm2 were included in this study. Fresh grafts were obtained from organ donors and the knee joint was harvest without violation of synovium capsule and then was transported to the tissue bank for processing. Donor and receptor tissue matching occurred according to size, localization and priority on waiting list and tissue was preserved in Ham F-12 - GIBCO media with glutamax (Invitrogen, Life Technologies, United States) and antibiotics. Surgical procedure was achieved with osteochondral plugs or shell techniques, with additional fixation when needed. Patients were evaluated with IKDC objective, IKDC subjective, KOOS and modified Merle D\'Aubigne-Postel outcome scores. Eight fresh osteochondral allografts were performed from march to october, 2012. The average age was 30.1 years old (17-44) and mean graft surface area was 10.6 cm2 (4.6 - 22.4 cm2). Average time from harvest to transplantation was 15.3 days (14-16 days) and mean number of previous surgical procedures was 2 (0 - 4 procedures). Pre-operative objective IKDC score was B in 12%, C in 25% and D in 63% and was A in 12% and B in 88% in 18 months follow-up. Pre-operative IKDC subjective and KOOS score were 31.99 ± 13.4 and 46.8 ± 20.9; and in 18 months follow-up were 81.84 ± 9.25 and 89.58 ± 7.06, respectively, with a significant increase along time on variance analysis (p < 0.01). Pre-operative mean modified Merle D\'Aubigne-Postel scores were 8.75 ± 2.25 and 16.75 ± 2.19 in 18 months follow-up. Non-parametric Friedman test analysis showed a significant progression in follow-up (p < 0.01). Standards of procurement, processing and utilization of fresh osteochondral allografts in the knee joint relay on a high specialized tissue bank and promote excellent results on the treatment of large osteochondral lesions, being a good alternative of a biologic repair for young patients in Brazil

Cheuk, Yau Chuk. / Thesis submitted in: Dec 2008. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 132-144). / Abstracts in English and Chinese. / ABSTRACT --- p.i / 論文摘要 --- p.iii / PUBLICATIONS --- p.v / ACKNOWLEDGEMENT --- p.vi / LIST OF ABBREBIVIATIONS --- p.vii / INDEX FOR FIGURES --- p.x / INDEX FOR TABLES --- p.xiv / TABLE OF CONTENTS --- p.xv / Chapter CHAPTER ONE - --- INTRODUCTION / Chapter 1.1 --- "Joint function, structure and biochemistry" / Chapter 1.1.1 --- Function of joint --- p.1 / Chapter 1.1.2 --- Types of cartilage --- p.1 / Chapter 1.1.3 --- Composition and structure of articular cartilage --- p.2 / Chapter 1.1.4 --- The subchondral bone --- p.3 / Chapter 1.1.5 --- Maturation of articular cartilage and subchondral bone --- p.3 / Chapter 1.2 --- Osteochondral defect / Chapter 1.2.1 --- Clinical problem --- p.6 / Chapter 1.2.2 --- Spontaneous repair --- p.7 / Chapter 1.2.3 --- Current treatment strategies --- p.7 / Chapter 1.2.4 --- Limitations of current treatment strategies --- p.8 / Chapter 1.2.5 --- Treatments under development --- p.11 / Chapter 1.2.6 --- Potential and limitations in cell therapies --- p.14 / Chapter 1.3 --- The 3-D scaffold-free cartilage / Chapter 1.3.1 --- Fabrication of scaffold-free cartilage --- p.16 / Chapter 1.3.2 --- Scaffold-free cartilage for chondral / osteochondral defect repair --- p.18 / Chapter 1.3.3 --- Scaffold-free bioengineered chondrocyte pellet from our group --- p.20 / Chapter 1.3.4 --- BCP as a possible treatment for OCD --- p.21 / Chapter 1.4 --- The objectives of the study --- p.22 / Chapter 1.5 --- The study plan / Chapter 1.5.1 --- Design of the study --- p.23 / Chapter 1.5.2 --- Choice of animal model --- p.23 / Chapter 1.5.3 --- Selection of evaluation time points --- p.24 / Chapter 1.5.4 --- Choice and modification of histological scoring system --- p.24 / Chapter CHAPTER TWO - --- METHODOLOGY / Chapter 2.1 --- Preparation of reagents and materials for tissue culture and histology --- p.26 / Chapter 2.2 --- Creation of osteochondral defect model --- p.28 / Chapter 2.3 --- Synthesis of scaffold-free cartilage using 3-D chondrocyte pellet culture / Chapter 2.3.1 --- Isolation of rabbit costal chondrocytes --- p.31 / Chapter 2.3.2 --- Three-dimensional chondrocyte pellet culture --- p.31 / Chapter 2.3.3 --- BrdU labeling for cell fate tracing --- p.32 / Chapter 2.4 --- Further characterization of the 3-D scaffold-free chondrocyte pellet / Chapter 2.4.1 --- Gross appearance --- p.35 / Chapter 2.4.2 --- Cell viability / Chapter 2.4.2.1 --- Alamar blue reduction assay --- p.35 / Chapter 2.4.3 --- Preparation of samples for histology --- p.36 / Chapter 2.4.4 --- General morphology and histomorphology / Chapter 2.4.4.1 --- H&E staining --- p.36 / Chapter 2.4.5 --- Cartilage properties / Chapter 2.4.5.1 --- Safranin O /Fast Green staining --- p.37 / Chapter 2.4.5.2 --- Immunohistochemistry of type II collagen --- p.37 / Chapter 2.4.5.3 --- Immunohistochemistry of type I collagen --- p.38 / Chapter 2.4.6 --- Angiogenic properties / Chapter 2.4.6.1 --- Immunohistochemistry of VEGF --- p.40 / Chapter 2.4.7 --- Osteogenic properties / Chapter 2.4.7.1 --- ALP staining --- p.40 / Chapter 2.5 --- Implantation of scaffold-free cartilage into osteochondral defect model / Chapter 2.5.1 --- Surgical procedures --- p.41 / Chapter 2.5.2 --- Experimental groups --- p.42 / Chapter 2.6 --- Assessment of osteochondral defect healing / Chapter 2.6.1 --- Macroscopic evaluation --- p.43 / Chapter 2.6.2 --- Preparation of samples for histology --- p.43 / Chapter 2.6.3 --- Histology for general morphology / Chapter 2.6.3.1 --- H&E staining --- p.45 / Chapter 2.6.4 --- Histological scoring / Chapter 2.6.4.1 --- Modification of the scoring system --- p.45 / Chapter 2.6.4.2 --- Procedures of scoring and validation --- p.45 / Chapter 2.6.5 --- Cell proliferation / Chapter 2.6.5.1 --- Immunohistochemistry of PCNA --- p.49 / Chapter 2.6.6 --- Cartilage regeneration / Chapter 2.6.6.1 --- Safranin O /Fast Green staining --- p.49 / Chapter 2.6.6.2 --- Immunohistochemistry of type II collagen --- p.49 / Chapter 2.6.6.3 --- Immunohistochemistry of type I collagen --- p.50 / Chapter 2.6.6.4 --- Polarized light microscopy --- p.50 / Chapter 2.6.7 --- Expression of angiogenic factor / Chapter 2.6.7.1 --- Immunohistochemistry of VEGF --- p.50 / Chapter 2.6.8 --- Bone regeneration / Chapter 2.6.8.1 --- μCT analysis --- p.50 / Chapter 2.6.9 --- Histomorphometric analysis of cartilage and bone regeneration --- p.53 / Chapter 2.6.10 --- BrdU detection for cell fate tracing --- p.55 / Chapter 2.6.11 --- Statistical analysis --- p.55 / Chapter CHAPTER THREE - --- RESULTS / Chapter 3.1 --- Further characterization of the 3-D chondrocyte pellet culture / Chapter 3.1.1 --- Gross examination --- p.57 / Chapter 3.1.2 --- Cell viability --- p.57 / Chapter 3.1.3 --- Cartilage properties --- p.61 / Chapter 3.1.4 --- Angiogenic properties --- p.63 / Chapter 3.1.5 --- Osteogenic properties --- p.64 / Chapter 3.2 --- Implantation of scaffold-free cartilage and assessment / Chapter 3.2.1 --- Gross examination --- p.65 / Chapter 3.2.2 --- General morphology --- p.67 / Chapter 3.2.3 --- Histological scores --- p.71 / Chapter 3.2.4 --- Cell proliferation --- p.75 / Chapter 3.2.5 --- Cartilage regeneration --- p.78 / Chapter 3.2.6 --- Expression of angiogenic factor --- p.90 / Chapter 3.2.7 --- Bone regeneration --- p.93 / Chapter 3.2.8 --- Histomorphometric analysis on cartilage and bone regeneration --- p.96 / Chapter 3.2.9 --- Cell fate tracing --- p.100 / Chapter CHAPTER FOUR - --- DISCUSSION / Chapter 4.1 --- Summary of key findings / Chapter 4.1.1 --- Further characterization of BCP and determination of implantation time --- p.102 / Chapter 4.1.2 --- Implantation of BCP in OCD --- p.102 / Chapter 4.2 --- Spontaneous healing in osteochondral defect / Chapter 4.2.1 --- Findings from the current study --- p.104 / Chapter 4.2.2 --- Comparison with other studies --- p.104 / Chapter 4.2.3 --- Factors affecting spontaneous healing --- p.105 / Chapter 4.3 --- Fabrication and further characterization of the 3-D chondrocyte pellet / Chapter 4.3.1 --- Comparison of different methods of producing scaffold-free cartilage construct --- p.106 / Chapter 4.3.2 --- Cartilage phenotype of the BCP --- p.107 / Chapter 4.3.3 --- Angiogenic and osteogenic potential of the BCP --- p.108 / Chapter 4.3.4 --- Role of mechanical stimulation on tissue-engineered cartilage --- p.109 / Chapter 4.4 --- Repair of osteochondral defect with allogeneic scaffold-free cartilage / Chapter 4.4.1 --- Advantages of the current scaffold-free chondrocyte pellet --- p.111 / Chapter 4.4.2 --- Remodeling of BCP after implantation --- p.111 / Chapter 4.4.3 --- Effect of BCP on cartilage repair --- p.112 / Chapter 4.4.4 --- Effect of BCP on bone regeneration / Chapter 4.4.4.1 --- Findings in the present study --- p.113 / Chapter 4.4.4.2 --- Possible reasons of slow bone repair --- p.114 / Chapter 4.4.4.3 --- Effect of BCP on bone region peripheral to defect --- p.115 / Chapter 4.4.5 --- Immunorejection-free properties of the BCP --- p.116 / Chapter 4.4.6 --- Comparison with other animal studies using scaffold-free cartilage --- p.117 / Chapter 4.4.7 --- Possibility of implanting a BCP cultured for shorter or longer period --- p.118 / Chapter 4.4.8 --- Scaffold-free cartilage construct and construct with scaffold for OCD repair --- p.119 / Chapter 4.4.9 --- Chondrocytes and stem cells for OCD repair --- p.120 / Chapter 4.5 --- Limitations of the study / Chapter 4.5.1 --- Animal model --- p.122 / Chapter 4.5.2 --- Histomorphometric analysis --- p.122 / Chapter 4.5.3 --- Lack of quantitative data analysis --- p.122 / Chapter 4.5.4 --- BrdU labeling of cells --- p.123 / Chapter 4.5.5 --- Lack of biomechanical test --- p.123 / Chapter 4.5.6 --- Small sample size --- p.123 / Chapter CHAPTER FIVE - --- CONCLUSION --- p.124 / Chapter CHAPTER SIX - --- FUTURE STUDIES / Chapter 6.1 --- Identification of factors affecting bone repair after OCD treatment --- p.125 / Chapter 6.2 --- Modifications of BCP treatment --- p.125 / Chapter 6.3 --- Alternative cell source --- p.126 / Chapter 6.4 --- Alternative cell tracking methods --- p.126 / Chapter 6.5 --- Inclusion of biomechanical test --- p.126 / APPENDICES / Appendix 1. Conference paper 1 --- p.129 / Appendix 2: Conference paper 2 --- p.130 / Appendix 3: Animal experimentation ethics approval --- p.131 / BIBLIOGRAPHY --- p.132

Aggrecan is one of the most important structural components of the extracellular matrix (ECM) of articular cartilage, where it contributes to the hydration of the tissue and its ability to resist compressive loads during joint movement. Increased aggrecan degradation and loss occurs in joint diseases and is thought to be mediated by enzymes such as the matrix metalloproteinases (MMPs) and aggrecanases (ADAMTS). It has also been proposed that aggrecan release from the cartilage can be mediated by a non-proteolytic mechanism which involves the degradation of hyaluronan (RA) to which the aggrecan is bound. As aggrecan degradation and loss is known to be induced by pro-inflammatory cytokines, IL-1, TNFalpha, IL-6, IL-17 and OSM were used to investigate the mechanisms involved in proteoglycan catabolism in organ cultures of bovine articular cartilage. Irrespective of the cytokine, all aggrecan fragments generated were characteristic of aggrecanase action, and no additional aggrecan-degrading enzymatic activity was detected. In the presence of OSM, more rapid aggrecan release was observed, due to both proteolysis and fragmentation of HA by hyaluronidase activity. Moreover, addition of OSM resulted in the cleavage of aggrecan at a non-canonical aggrecanase site near its carboxy-terminal globular domain. Such cleavage could be reproduced in vitro by the action of either ADAMTS-4 or ADAMTS-5. Gene expression analysis revealed that both aggrecanases were highly induced by the cytokines, and while ADAMTS-4 was the major aggrecanase to be stimulated in all conditions, ADAMTS-5 remains the predominant aggrecanase to be expressed in cartilage. Thus, the present study shows that aggrecanase activity is primarily responsible for aggrecan degradation in the early stages of cytokine stimulation, and that in the presence of OSM, aggrecanase substrate specificity can be differentially modulated and hyaluronidase-mediated RA degradation can be induced.

Thesis (Ph.D. in Clinical Science) -- University of Colorado at Denver and Health Sciences Center, 2006. / Typescript. Includes bibliographical references (leaves 107-128). Free to UCDHSC affiliates. Online version available via ProQuest Digital Dissertations;

Diss. (sammanfattning) Linköping : University, 2003. / Härtill 5 uppsatser.

Thesis (M.S.)--University of Missouri--Columbia, 2003. / "December 2003." Typescript. Vita. Includes bibliographical references (leaves 84-96). Also issued on the Internet.

Thesis (M.S.)--University of Missouri--Columbia, 2004. / "July 2004." Typescript. Includes bibliographical references (leaves 63-70). Also issued on the Internet. Also available on the Internet.