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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.
61

Análise imunohistoquímica da ADAMTS-1 e proteoglicanos no ameloblastoma e no tumor odontogênico cístico calcificante / Immunohistochemistry analysis of ADAMTS-1 and proteoglycans in ameloblastoma and calcifying odontogenic tumor

SOUZA NETO, Osvaldo Rodrigues de 30 June 2014 (has links)
Submitted by Cleide Dantas (cleidedantas@ufpa.br) on 2014-10-01T13:02:23Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_AnaliseImunohistoquímicaAdamts.pdf: 2182822 bytes, checksum: f614e4856b0e4ff30df45d31a8939a93 (MD5) / Approved for entry into archive by Ana Rosa Silva (arosa@ufpa.br) on 2014-10-07T13:13:41Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_AnaliseImunohistoquímicaAdamts.pdf: 2182822 bytes, checksum: f614e4856b0e4ff30df45d31a8939a93 (MD5) / Made available in DSpace on 2014-10-07T13:13:41Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_AnaliseImunohistoquímicaAdamts.pdf: 2182822 bytes, checksum: f614e4856b0e4ff30df45d31a8939a93 (MD5) Previous issue date: 2014 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O ameloblastoma e o tumor odontogênico cístico calcificante (TOCC) são tumores odontogênicos que tem origem do epitélio odontogênico, porém ainda não é conhecido o estímulo ou gatilho que leva à transformação neoplásica desses tumores. O comportamento biológico das lesões é distinto, pois o ameloblastoma é um tumor mais agressivo e com taxa de recorrência significativa. Já o TOCC é um tumor menos agressivo e raramente há recorrência e por esse motivo foi utilizado como controle no estudo. Portanto, a elucidação completa dos mecanismos pelos quais esses tumores odontogênicos apresentam tais comportamentos biológicos continua sendo um desafio para os pesquisadores. As c (A Disintegrin and Metalloproteinase with ThromboSpondin) são metaloendopeptidases que são dependentes de zinco em seu domínio catalítico. Essas enzimas possuem ampla atividade catalítica contra uma variedade de substratos como os proteoglicanos (agrecan, brevican e versican), que são proteínas presente na matriz extracelular (MEC). As ADAMTS exibem características estruturais que lhes conferem um grande potencial para exibir múltiplas funções. Exibem função crucial em vários processos como proliferação, adesão, invasão e sinalização celular. As alterações nessas enzimas estão presentes em diversos tumores, o que sugere que estas proteínas podem estar envolvidas no processo carcinogênico em diferentes caminhos. Especificamente a ADAMTS-1 tem sido correlacionada com a tumorigênese de algumas neoplasias como no câncer de mama, pulmão e pâncreas. Assim como a ADAMTS, agrecan, brevican e versican são expressos em vários tumores e a regulação alterada desses proteoglicanos pode contribuir para o desenvolvimento da carcinogênese. Neste trabalho foram estudadas ADAMTS-1, agrecan, brevican e versican no ameloblastoma e TOCC. Foram incluídos 20 casos de ameloblastoma e 6 casos de TOCC, utilizados como controle. A expressão de ADAMTS-1, agrecan, brevican e versican foi avaliada por imunohistoquímica e as áreas de marcação foram mensuradas e analisadas. Para análise de correlação entre as proteínas estudadas utilizou-se o teste de Spearman. Todas as amostras de ameloblastoma expressaram ADAMTS-1, agrecan, brevican e versican. Todas as amostras de TOCC também expressaram as mesmas proteínas, porém numa quantidade significativamente menor que no ameloblastoma. A diferença de expressão de ADAMTS-1 e brevican no epitélio do ameloblastoma e do TOCC foi significante estatisticamente (p<0,0105). Assim como a expressão de agrecan e versican, no epitélio do ameloblastoma e do TOCC, também foi estatisticamente significante (p<0,0067) e (p<0,0148), respectivamente. Não houve correlação entre as proteínas estudadas. / Ameloblastoma and calcifying cystic odontogenic tumor (CCOT) are odontogenic tumors with origin odontogenic epithelium, but it is not yet known stimulus or trigger that lead to neoplastic transformation of tumors. The biological behavior of the lesions is distinct because the ameloblastoma is more aggressive and significant rate of tumor recurrence. CCOT is a less aggressive tumor and recurrence rarely there and therefore was used as a control in the study. Therefore, the complete elucidation of the mechanisms by which these odontogenic tumors show such biological behavior remains a challenge for researchers. The ADAMTS (A Disintegrin and Metalloproteinase with thrombospondin) are metalloendopeptidases who are dependent on zinc in its catalytic domain. These enzymes have catalytic activity against a broad range of substrates including proteoglycans (aggrecan, brevican and versican), which are proteins present in the extracellular matrix (ECM). The ADAMTS exhibit structural features that confer great potential to display multiple functions. Exhibit crucial role in various processes such as proliferation, adhesion, invasion and cell signaling. Changes to these enzymes are present in various tumors, suggesting that these proteins may be involved in the carcinogenic process in different ways. Specifically, ADAMTS-1 has been correlated with tumorigenesis of some cancers such as in breast, lung and pancreatic cancer. Like ADAMTS, aggrecan, versican and brevican are expressed in various tumors and altered regulation of proteoglycans may contribute to the development of carcinogenesis. In this work ADAMTS-1, aggrecan, brevican and versican in ameloblastoma and CCOT were studied, 20 cases of ameloblastoma and 6 cases of TOCC, used as controls were included. We evaluated the expression of ADAMTS-1, aggrecan, brevican and versican by immunohistochemical study and the marking areas were measured and analyzed. To correlation analysis between the studied proteins used the Spearman test. All samples of ameloblastoma expressed ADAMTS-1, aggrecan, brevican and versican. All samples TOCC also expressed the same proteins, but in significantly less than the amount ameloblastoma. The difference in expression of ADAMTS-1 and brevican in the epithelium of ameloblastoma and of TOCC was statistically significant (p<0.0105). As the expression of aggrecan and versican, between ameloblastoma and TOCC, in the epithelium was also statistically significant (p<0.0067) and (p<0.0148), respectively. There was no correlation between the proteins studied.
62

Estudo imuno-histoqu?mico da presen?a de miofibroblastos e da express?o do fator transformador de crescimento-beta1, interferon gama, metaloproteinase de matriz 13 e indutor de metaloproteinases de matriz em les?es odontog?nicas epiteliais

Santos, Pedro Paulo de Andrade 28 February 2012 (has links)
Made available in DSpace on 2015-03-03T15:38:43Z (GMT). No. of bitstreams: 1 PedroPAS_TESE_1-70.pdf: 4719637 bytes, checksum: 8f16cb0e2326a80cfc947b1ea2b89641 (MD5) Previous issue date: 2012-02-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Myofibroblasts are cells that exhibit a hybrid phenotype, sharing the morphological characteristics of fibroblasts and smooth muscle cells, which is acquired during a process called differentiation. These cells then start to express -SMA, a marker that can be used for their identification. Studies suggest that myofibroblasts are related to the aggressiveness of different tumors and that TGF-1 and IFN- play a role in myofibroblast differentiation, stimulating or inhibiting this differentiation, respectively. The objective of this study was to investigate the role of myofibroblasts in epithelial odontogenic tumors, correlating the presence of these cells with the aggressiveness of the tumor. Immunohistochemistry was used to evaluate the expression of TGF-1 and IFN- in myofibroblast differentiation, as well as the expression of MMP-13, which is activated by myofibroblasts, and of EMMPRIN (extracellular matrix metalloproteinase inducer) as a precursor of this MMP. The sample consisted of 20 solid ameloblastomas, 10 unicystic ameloblastomas, 20 odontogenic keratocysts, and 20 adenomatoid odontogenic tumors. For evaluation of myofibroblasts, anti- -SMA-immunoreactive cells were quantified in connective tissue close to the epithelium. Immunoexpression of TGF-1, IFN-, MMP-13 and EMMPRIN was evaluated in the epithelial and connective tissue components, attributing scores of 0 to 4. The results showed a higher concentration of myofibroblasts in solid ameloblastomas (mean of 30.55), followed by odontogenic keratocysts (22.50), unicystic ameloblastomas (20.80), and adenomatoid odontogenic tumors (19.15) (p=0.001). No significant correlation between TGF-1 and IFN- was observed during the process of myofibroblast differentiation. There was also no correlation between the quantity of myofibroblasts and MMP-13 expression. Significant correlations were found between MMP-13 and TGF-1 (r=0.087; p=0.011), between MMP- 13 and IFN- (r=0.348; p=0.003), as well as between EMMPRIN and MMP-13 (r=0.474; p<0.001) and between EMMPRIN and IFN- (r=0.393; p=0.001). The higher quantity of myofibroblasts observed in solid ameloblastomas, odontogenic keratocysts and unicystic ameloblastomas suggests that these cells are one of the factors responsible for the more aggressive biological behavior of these tumors, although the myofibroblast population was not correlated with TGF-1, IFN-, MMP-13 or EMMPRIN. The correlation between MMP- 13 and TGF-1 suggests that the latter induces the expression of this metalloproteinase. The present results also support the well-established role of EMMPRIN as an inducer of MMP-13. Furthermore, the relationship between EMMPRIN and IFN- and between MMP-13 and IFN- suggests synergism in the antifibrotic effect of these markers / Os miofibroblastos s?o c?lulas que apresentam um fen?tipo h?brido exibindo caracter?sticas morfol?gicas de fibroblastos e de c?lulas musculares lisas, sendo a aquisi??o de tal fen?tipo denominada diferencia??o, passando ent?o a expressar a -SMA, a qual ? importante na identifica??o dessas c?lulas. Estudos t?m sugerido que os miofibroblastos apresentam rela??o com a agressividade de diversas les?es e que o seu processo de diferencia??o estaria relacionado ? express?o do TGF- 1 e do IFN- atuando, respectivamente, no est?mulo e na inibi??o dessa diferencia??o. O objetivo deste trabalho foi investigar o papel dos miofibroblastos em les?es odontog?nicas epiteliais, relacionando-os ? agressividade das les?es e analisar por meio da imuno-histoqu?mica, a express?o do TGF- 1 e IFN- no processo de diferencia??o, al?m da an?lise da MMP-13 que ? ativada por miofibroblastos e do indutor de metaloproteinases de matriz (EMMPRIN) como precursor desta MMP. A amostra foi constitu?da por 20 ameloblastomas s?lidos, 10 ameloblastomas unic?sticos, 20 ceratocistos odontog?nicos e 20 tumores odontog?nicos adenomat?ides. Para a avalia??o dos miofibroblastos, foram quantificadas as c?lulas imunorreativas ao anticorpo - SMA presentes no tecido conjuntivo, pr?ximo ao tecido epitelial. As express?es de TGF- 1, IFN- , MMP-13 e EMMPRIN, foram avaliadas no componente epitelial e no conjuntivo, estabelecendo-se o percentual de imunorreatividade e atribuindo-se escores de 0 a 4. A an?lise dos miofibroblastos evidenciou maior concentra??o nos ameloblastomas s?lidos (m?dia de 30,55), seguido pelos ceratocistos odontog?nicos (22,50), ameloblastomas unic?sticos (20,80) e tumores odontog?nicos adenomat?ides (19,15) com valor de p= 0,001. N?o foi encontrada correla??o significativa entre TGF- 1 e IFN- no processo de diferencia??o dos miofibroblastos, bem como na rela??o entre a quantidade de miofibroblastos e a express?o da MMP-13. Constatou-se, correla??o estat?stica entre MMP-13 e TGF- 1 (r= 0,087; p= 0,011) al?m de significante correla??o entre MMP-13 e IFN- (r=0,348; p=0,003). Entre EMMPRIN e MMP-13 verificou-se signific?ncia (r= 0,474; p<0,001) assim como entre EMMPRIN e IFN- (r=0,393; p=0,001). A maior quantidade de miofibroblastos evidenciada nos ameloblastomas s?lidos, ceratocistos odontog?nicos e ameloblastomas unic?sticos sugere que estas c?lulas podem ser um dos fatores respons?veis para um comportamento biol?gico mais agressivo destas les?es, embora a popula??o de miofibroblastos n?o tenha apresentado correla??o com TGF- - 1, IFN- ,MMP-13 e EMMPRIN. Quanto a correla??o evidenciada entre MMP-13 e TGF- 1, isto pode sugerir um papel indutor do TGF- 1 para a express?o da MMP-13, assim como os resultados deste estudo refor?am a rela??o bem estabelecida do EMMPRIN como indutor da MMP-13. Constatou-se tamb?m rela??o entre EMMPRIN e IFN- assim como entre MMP-13 e IFN- sugerindo, dessa forma, um sinergismo na a??o anti-fibr?tica desses marcadores
63

Proliferation and expression of p53 in odontogenic tumours - An immunohistochemical analysis

Wassberger, Johanna, Yarahmadi, Mahtab January 2017 (has links)
Introduktion: Ameloblastom (AB), adenomatoid odontogen tumör (AOT), ameloblastiskt fibrom (AF) och odontogent fibrom (OF) är odontogena tumörer som innehåller epiteliala komponenter. Frekvensen av recidiv hos dessa varierar från låg förekomst till relativt hög förekomst. Syftet med denna studie är att undersöka om Ki-67, p53 och BRAF kan användas som prognostiska markörer i recidivmönstret hos dessa tumörer.Material och metod: Studien genomfördes genom immunohistokemi med monoklonala antikroppar av Ki-67, p53 och BRAF på respektive tumör. Tumörerna hämtades från avdelningen för Oral patologi på Malmö högskola. En statistisk analys utfördes med hjälp av Kruskal-Wallis envägs-ANOVA.Resultat: I de tio AB-fallen kunde en hög proliferation och en hög prevalens av muterade p53 ses. I de sju fallen av AOT kunde en måttligt hög proliferation och en generellt hög prevalens av muterade p53, jämförbara med värden för AB, ses. De sju fallen med AF och de fem fallen med OF visade båda en låg proliferation och en låg förekomst av muterade p53. Skillnaden mellan gruppen AB och AOT och gruppen AF och OF visade en signifikant högre infärgningsintensitet för både Ki-67 (p<0.001) och p53(p=0.001) för gruppen med AB och AOT.Konklusion: Proliferations index med Ki-67 och förekomst av p53-mutationer kan användas som en prognostisk markör för recidiv hos AB och AOT. Det är å andra sidan inte tillämpbart för AF och OF. / Introduction: Ameloblastoma (AB), adenomatoid odontogenic tumour (AOT), ameloblastic fibroma (AF) and odontogenic fibroma (OF) are all odontogenic tumours with an epithelial component. The recurrence rate for these odontogenic tumours varies from low frequencies to quite high frequencies. The aim of this study is to evaluate the expression of Ki-67, p53 and BRAF and the possibility of these antibodies acting as prognostic markers in the recurrence pattern of odontogenic tumours.Material and method: An immunohistochemical study using Ki67, p53 and BRAF monoclonal antibodies was performed on 29 paraffin blocks from the respective tumours obtained at the department of Oral Pathology in the Faculty of Odontology at Malmö University. Statistical analysis was performed with Kruskal-Wallis one-way ANOVA.Results: In the series of ten AB cases high proliferation activity and a high prevalence of p53 mutations was observated. In the seven AOT cases a moderately high proliferative activity as well as a generally high prevalence of p53 mutation, comparable to AB, was observed. The seven cases of AF and the five cases of OF demonstrated a low proliferative activity and a low prevalence of p53 mutation. The difference between AB and AOT versus AF and OF as two separate groups, showed a significantly higher staining intensity for both Ki-67 (p < 0.001) and p53 (p = 0.001) in AB and AOT as a group.Conclusion: Ki-67 proliferation index and p53-mutation status can be considered to be a prognostic marker for AB and AOT recurrence. This is, however, not applicable to AF and OF.

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