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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.
161

Desequilibrio entre alfa distroglicana (alfa-DG) e metaloproteinase de matriz 9 (MMP-9) no carcinoma urotelial da bexiga e do trato urinario superior : um novo modelo animal / Alph dystroglycan (alfa-DG) and matrix metalloproteinase 9 (MMP-9) imblance on bladder and upper urinary tract uruthelial carcinoma : a new animal model

Reis, Leonardo Oliveira, 1978- 07 January 2009 (has links)
Orientadores: Ubirajara Ferreira, Valeria H. A. Cagnon Quitete / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-13T17:35:54Z (GMT). No. of bitstreams: 1 Reis_LeonardoOliveira_M.pdf: 4339458 bytes, checksum: 1e103884dabb1194ecfd6161caeed83d (MD5) Previous issue date: 2009 / Resumo: A destruição do complexo da distroglicana dependente da metaloproteinase da matriz pode ter papel importante no desenvolvimento e progressão do tumor urotelial. O carcinoma urotelial humano é frequente na bexiga e menos comum no trato urinário superior. Não há um modelo experimental animal bem definido e reprodutível de carcinoma urotelial do trato superior. Objetivos: Propor um novo modelo experimental de carcinoma urotelial que resulta de refluxo vesicoureteral em animais submetidos a tratamento com associação entre n-metil-n-nitrosourea e citrato de sódio intravesicais. Caracterizar a imunolocalização dos receptores de ?-distroglicana e metaloproteinase 9 na bexiga urinária, ureter e pelve renal deste modelo, assim como descrever aspectos morfológicos, imunohistoquímicos e proliferativos nestes órgãos. Metodologia: Cinqüenta ratas Fisher 344 foram divididas em dois grupos: Controle - recebeu 0,30ml de solução salina 0,9% intravesical; MNU-citrato - recebeu 0,15ml de MNU e 0,15ml de citrato de sódio intravesical, ambos em semanas alternadas, nas semanas 0, 2, 4 e 6, totalizando quatro doses. Após 15 semanas de tratamento, a bexiga, os ureteres, e as pelves renais foram coletados para análises morfológicas e imunohistoquímicas. Resultados: O grupo MNU-Citrato apresentou imunoreatividade reduzida de ?-DG e aumentada de MMP-9 e Ki-67. O tratamento associado de MNU e citrato de sódio levou ao desenvolvimento de carcinoma urotelial na bexiga e no trato urinário superior de todos os animais. Conclusões: O modelo proposto induziu lesão maligna de diversos graus em 100 % dos animais, sem comprometimento muscular. A imunolocalização da ?-DG foi muito diminuída em contraposição ao aumento da imunolocalização da MMP-9 nos diferentes órgãos estudados neste modelo e os aspectos morfológicos, imunohistoquímicos e proliferativos ao longo do urotélio (bexiga urinária, ureter e pelve renal) foram muito semelhantes, sendo que ocorreu aumento de apoptose e proliferação celular com expressivo predomínio deste último. Palavras chave: Distroglicana; Metaloproteinase de matriz; Carcinoma urotelial; Modelo animal experimental; Trato urinário superior / Abstract: The dystroglican complex destruction is done by matrix metalloproteinase and plays a critical role in the urothelial carcinoma development and progression. The human urothelial carcinoma is frequent on the bladder and less common on the upper urinary tract. There is no reproducible and well described experimental upper urothelial carcinoma model on this issue. Purposes: Describe a novel experimental upper urothelial carcinoma animal model which results in vesicoureteral reflux in animals submitted to associate treatment with the carcinogen n-methyl-n-nitrosourea and sodium citrate intravesically. Characterize the ?-DG and the MMP-9 immunolocalization in the bladder as well as in the upper urinary tract, and describe morphological, immunohistochemistry and proliferative aspects utilizing a novel experimental model. Materials and Methods: Fifty female Fischer 344 rats were divided into two groups: the control group received a 0.30ml dose of 0.9% physiological saline intravesically every other week for a total of 4 doses; the MNU-citrate group received 0.15 ml of MNU and 0.15ml of sodium citrate intravesically every other week for a total of 4 doses. After 15 weeks of treatment, bladder, ureters and renal pelvis were collected for morphological and immunohistochemistry analyses. Results: The MNU-Citrate group showed reduced ?-DG and increased MMP-9 and Ki-67 immunoreactivities. Associated treatment with MNU and sodium citrate was able to lead to both urinary bladder and upper urinary tract tumors in all animals. Conclusions: The proposed model showed cancer in several grades in 100 % of animals, with no muscular invasion. The immunolocalization was decreased for ?-DG and increased for MMP-9 in the analyzed tissues and the morphological, immunohistochemical and proliferative aspects of the urothelium (bladder, ureter e renal pelvis) were similar. Apoptosis and proliferation were increased, being the last one more intense / Mestrado / Cirurgia / Mestre em Cirurgia
162

Tetraciclinas quimicamente modificadas como inibidores de metaloproteinases de matriz (MMPS): um estudo de estrutura, reatividade, dinâmica e implicações biológicas

Marcial, Bruna Luana 26 July 2013 (has links)
Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2016-08-08T16:42:04Z No. of bitstreams: 1 brunaluanamarcial.pdf: 8389291 bytes, checksum: 93256796394730c4d8f7a200fe2be582 (MD5) / Rejected by Adriana Oliveira (adriana.oliveira@ufjf.edu.br), reason: tentar corrigir a fórmula no resumo on 2016-08-09T11:35:20Z (GMT) / Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2016-08-09T11:47:58Z No. of bitstreams: 1 brunaluanamarcial.pdf: 8389291 bytes, checksum: 93256796394730c4d8f7a200fe2be582 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-08-09T11:51:59Z (GMT) No. of bitstreams: 1 brunaluanamarcial.pdf: 8389291 bytes, checksum: 93256796394730c4d8f7a200fe2be582 (MD5) / Made available in DSpace on 2016-08-09T11:52:00Z (GMT). No. of bitstreams: 1 brunaluanamarcial.pdf: 8389291 bytes, checksum: 93256796394730c4d8f7a200fe2be582 (MD5) Previous issue date: 2013-07-26 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / As Metaloproteinases de Matriz (MMPs) desempenham um papel crucial nos processos fisiológicos e condições patológicas tais como progressão tumoral e metástases. Nos últimos anos, tem sido proposto uma série de inibidores de MMPs (IMMPs), incluindo as Tetraciclinas Quimicamente Modificadas (CMTs), as quais têm apresentado resultados promissores em ensaios com modelos pré-clínicos de câncer. No entanto, até o presente não havia nenhum estudo da estrutura-atividade desses compostos. Neste sentido, na presente tese foram combinadas as metodologias teóricas da Teoria do Funcional da Densidade (DFT), Docking molecular e simulação de Dinâmica Molecular (DM) para elucidar o mecanismo de interação das CMTs com o sítio ativo das MMPs. Primeiramente a estrutura e estabilidade dos modelos moleculares miméticos do sítio ativo da MMP-2 representados por: [Zn(LHn)(H2O)2]2+x (n = 0, 1, 2 e x = -2, -1, 0) e [Zn(L)(His)3], onde L representa CMT1, -3, -4, -7 e -8, foram calculados usando DFT. O efeito do solvente e do pH foram também avaliados. Os resultados sugerem que a coordenação com o zinco ocorra no sítio VI(O11O12), o qual é igualmente favorável para a CMT-3 (log β = 15,9) e CMT-8 (log β = 21,3). Esta análise inicial evidenciou que a atividade das CMTs como inibidoras de MMP estaria diretamente relacionada à sua estrutura. Na segunda fase do trabalho foi investigada a interação das CMTs diretamente com o sítio ativo da MMP-2 (1QIB) combinando os métodos de docking molecular, simulações de DM e cálculos de energia livre. Um novo conjunto de parâmetros para os átomos de Zn(II) estrutural e catalítico da enzima foi calculado, validado e depositado dentro do campo de forças AMBER. As CMTs foram otimizadas no nível B3LYP/6-31G(d) e “docadas” dentro do sítio ativo da MMP-2. As melhores soluções foram minimizadas e submetidas a 12ns de simulação de DM. A energia livre de ligação foi calculada usando as metodologias de integração termodinâmica e MMPBSA. Os principais resultados mostram que as CMTs coordenam-se ao Zn(II) através do sítio VI(O11-O12), como proposto experimentalmente. Com exceção do análogo CMT-3 que está envolvido em contatos hidrofóbicos e interações de van der Waals com aminoácidos do bolso S1’da enzima e ainda interage com o Zn(II) pelo O11. A análise da energia livre de ligação revela uma maior afinidade entre o análogo CMT-3 com o sítio ativo da MMP-2, seguido pela CMT-7 e CMT-8, sendo que a diferença de energia varia apenas de 3 kcal mol1. De acordo com os resultados, é possível inferir que a ocupação do canal S1’ seria um fator fundamental para a resposta biológica da CMT-3, enquanto que as demais CMTs, por impedimento estérico, não entram no túnel hidrofóbico da enzima. Os resultados apresentados nesta tese tratam do primeiro estudo em nível molecular da interação de CMTs com metaloproteínas, como contribuição para a compreensão das observações experimentais, sobretudo dos testes biológicos, e ainda uma referência direta para o desenho de novos análogos das CMTs com maior potencial biológico. / Matrix Metalloproteinases (MMPs) play a critical role in physiological processes and pathological conditions such as tumor progression and metastasis. In recent years, a number of MMP inhibitors (MMPIs) have been proposed, including the chemically modified tetracyclines (CMTs), which have been evaluated in preclinical cancer models showing promising results. However, until present there were no studies on the structure-activity relationship for these compounds. In this sense, the present thesis focuses on the direct interaction of CMTs with the active site of the MMPs. Density Functional Theory (DFT), molecular docking and molecular dynamics (MD) simulations were accomplished for seven CMT derivatives. Firstly the structure and stability of mimetic molecular models of active site of MMP-2 represented by: [Zn(LHn)(H2O)2]2+x (n = 0, 1, 2 and x = -2, -1, 0) and [Zn(L)(His)3], where L=CMT-1, CMT-3, CMT-4, CMT-7 and CMT-8, were calculated at DFT level. The solvent and pH effects were also evaluated. The results suggested that the coordination at the O11-O12 site (site VI) was quite favorable to CMT-3 (log β = 15,9) and CMT-8 (log β = 21,3). This initial analysis showed that the activity of CMTs as inhibitors of MMP is directly related to its structure. In the second stage of the study, we investigated the interaction of CMTs directly with the active site of MMP-2 (1QIB). New sets of parameters were proposed for structural and catalytic zinc atoms in order to study MMPs and their complexes by means of the AMBER force field. The CMTs ligands were optimized at the B3LYP/6-31G(d) and docked onto the active site of MMP-2. The best solutions were minimized and subjected to 12ns MD simulation. The binding free energy was calculated using the methods of thermodynamic integration and MM-PBSA. The main results showed that the CMTs bind to the catalytic zinc of the MMP-2 enzyme through the O11-O12 moiety (site VI) as proposed experimentally. The exception was the CMT-3 analogue which is involved in hydrophobic contacts and van der Waals interactions with amino acids of the S1’ pocket in the MMP-2 enzyme and also interacts with the Zn (II) by O11. The binding energy calculated in solution predicts the CMT-3 complexes as the most favorable, followed by the CMT-7 and CMT-8 analogues, whose energy difference is within 3 kcal mol-1. These results suggest that the occupancy of S1’ pocket is an important molecular feature for biological response of CMT-3, while the other CMTs do not enter the hydrophobic tunnel of the enzyme due to the steric hindrance. The results presented in this thesis are the first step towards understanding the mechanism of CMTs as MMP inhibitors at a molecular level and could be a significant contribution to the understanding of experimental observations, especially the biological tests and the CMTs action mechanism as MMP inhibitors, allowing the design of new analogues with enhanced biological potency.
163

Expressão das proteínas MMP-2, MMP-9, MMP-14, TIMP-1, TIMP-2 e VEGF-A na NIC 3 e no carcinoma invasor do colo do útero = Expression of the proteins MMP-2, MMP-9, MMP-14, TIMP-1, TIMP-2 and VEGF-A in the CIN 3 and cervical cancer / Expression of the proteins MMP-2, MMP-9, MMP-14, TIMP-1, TIMP-2 and VEGF-A in the CIN 3 and cervical cancer

Westin, Maria Cristina do Amaral, 1949- 23 August 2018 (has links)
Orientadores: Luiz Carlos Zeferino, Silvia Helena Rabelo dos Santos / Texto em português e inglês / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-23T06:30:30Z (GMT). No. of bitstreams: 1 Westin_MariaCristinadoAmaral_D.pdf: 3122088 bytes, checksum: 3d2afed3690cd3566bbb3fe26bb492a3 (MD5) Previous issue date: 2013 / Resumo: Introdução: O carcinoma escamoso do colo uterino é precedido pela neoplasia intraepitelial cervical grau 3 (NIC 3). A invasão tumoral envolve a degradação da matriz extracelular e membrana basal do epitélio por enzimas proteolíticas denominadas metaloproteinases (MMPs). Os inibidores teciduais das metaloproteinases (TIMPs) também interferem no processo de invasão. Angiogênese é condição indispensável para a progressão tumoral. Objetivo: Analisar a expressão de MMP-2, MMP-9, MMP-14, TIMP-1, TIMP-2 e VEGF-A na NIC 3 e carcinoma do colo uterino. Sujeito e Métodos: Estudo do tipo comparativo observacional constituído de três grupos:- Grupo 1: 55 casos com diagnóstico de NIC 3, Grupo 2: 30 casos com NIC 3 e carcinoma associados e Grupo 3: 46 casos com carcinoma. A expressão protéica foi pesquisada separadamente nas células tumorais e estromais por reação imunoistoquímica. Para estabelecer a porcentagem de células imunopositivas utilizou-se software morfométrico. Análise Estatística: Aplicou-se o Teste T-pareado ou de Mann-Whitney ou Wilcoxon Signed Rank. Resultados: Em todos os grupos, a expressão tumoral de MMP-14 foi maior que a estromal. Inversamente, a expressão de TIMP-2 foi maior nas células estromais que nas tumorais, em cada grupo diagnóstico. A expressão de MMP-9 foi maior nas células estromais que nas tumorais, com exceção do componente invasor do Grupo 2. A expressão estromal de TIMP-1 foi maior que a tumoral no carcinoma e, ao contrário, sua expressão foi maior nas células tumorais da NIC 3. A expressão de VEGF-A foi maior apenas nas células tumorais da NIC 3. Comparando a expressão dos marcadores entre os grupos, foram encontradas as maiores diferenças entre grupos extremos, ou seja, entre NIC 3 e carcinoma. A expressão de MMP-2 nas células estromais foi maior no componente NIC 3 do Grupo 2 que no NIC 3 do Grupo 1. A expressão de VEGF-A nas células estromais do carcinoma foi maior que nas células estromais da NIC 3. Conclusões: Os resultados deste estudo sugerem que a expressão de TIMP-1 aumenta nas células do estroma e diminui nas células tumorais quando a NIC 3 progride para carcinoma invasor. MMP-9 e TIMP-2 tiveram expressão similar na NIC 3 e no carcinoma, o que limita inferências sobre seu papel na progressão neoplásica. O padrão imunoistoquímico da expressão das MMPs, TIMPs e VEGF-A na NIC 3 e no carcinoma invasivo, quando estas lesões estavam associadas, foi semelhante. A expressão do VEGF-A foi maior nas células tumorais do que nas estromais da NIC 3, porém quando esta lesão progride para carcinoma invasivo sua expressão aumenta nas células do estroma e não se altera nas tumorais. A expressão de MMP-14, MMP-2, TIMP-1 e VEGF-A aumentou com a gravidade da neoplasia / Abstract: Introduction: Squamous cell carcinoma of the cervix is preceded by cervical intraepithelial neoplasia grade 3 (CIN 3). Tumor invasion involves degradation of extracellular matrix and epithelium basement membrane by proteolytic enzymes called metalloproteinases (MMPs). Tissue inhibitors of metalloproteinases (TIMPs) are also involved in the invasion process. Angiogenesis is a prerequisite for tumor progression. Objective: To analyze the expression of MMP-2, MMP-9 and MMP-14, TIMP-1, TIMP-2 and VEGF-A in CIN 3 and invasive carcinoma. Subject and Methods: This comparative observational study was consists of three groups: Group 1: 55 cases diagnosed with CIN 3, Group 2: 30 cases with CIN 3 associated with invasive carcinoma and Group 3: 46 cases with invasive carcinoma. Protein expression was investigated separately in tumor and stromal cells by immunohistochemistry and evaluated by the percentage of cells positive for immunostaining using morphometric software. Statistical Analysis: Was performed applying paired t-test or Mann-Whitney or Wilcoxon Signed Rank. Results: In each diagnostic group, expression markers were significantly higher: MMP-14 in tumor cells, and TIMP-2 in stromal cells; also MMP-9 expression was significantly higher in stromal cells, except in invasive component of group 2, and TIMP-1 had significantly higher expression in stromal cells of invasive carcinoma and in tumor cells of CIN 3. VEGF-A expression was significantly higher only in tumor cells CIN 3. Comparing the expression of markers between groups, two by two, we find the greatest differences between the extreme groups, i.e. between invasive carcinoma and CIN 3. The expression of MMP-2 was significantly greater in the stromal component CIN 3 in group 2 than in CIN 3 only. The expression of VEGF-A was significantly higher in the group stromal cell carcinoma when compared to stromal cells CIN 3. Conclusions: The results of this study suggest that the expression of TIMP-1 increases in the stromal cells and decreases in tumor cells when CIN 3 progresses to invasive carcinoma. MMP-9 and TIMP-2 had similar expression in CIN 3 and invasive carcinoma, which limits inferences about its role in neoplastic progression. The immunohistochemical pattern of expression of MMPs, TIMPs and VEGF-A in CIN 3 and invasive carcinoma, as these lesions were associated, was similar. The expression of VEGF-A was higher in tumor cells than in stromal cells in CIN 3, but when the lesion progresses to invasive carcinoma its expression increases in the stromal cells and the tumor cells does not change. The expression of MMP-14, MMP-2, TIMP-1 and VEGF-A was increased with the severity of the neoplasia / Doutorado / Oncologia Ginecológica e Mamária / Doutora em Ciências da Saúde
164

Avaliação da proporção de células mononucleares e de MMP-2 e 9 na periodontite crônica em fumantes e não-fumantes / Assessmentof the proportion of mononuclearcellsand MMP-2 and 9 inchronic periodontitisin smokers and non-smokers

Cruz, Luis Eduardo Rilling da Nova 01 June 2010 (has links)
Made available in DSpace on 2014-08-20T14:30:09Z (GMT). No. of bitstreams: 1 Tese_luiz_eduardo_rilling_nova_cruz.pdf: 941247 bytes, checksum: b51c3277dc5892c9cf7c0ddc659e85c4 (MD5) Previous issue date: 2010-06-01 / The objective of the present study was the immunohistochemical evaluation of the proportion of mononuclear cells and the expression of MMP-2 and 9 on chronic periodontitis between smokers and non-smokers. From the 127 patients examined 31(16 non-smokers and 15 smokers) fulfill the inclusion criteria were included in the study. These patients underwent surgical procedures and 31 biopsies were collected and divided in two parts, one for histological preparation and the other for zymography. Each sample was histologically processed and exposed to monoclonal antibodies for B cells (anti-CD20), memory T cells (anti-CD45RO) and macrophages or monocytes (anti-CD68) detection. The samples showed a similar pattern, with connective tissue rich in inflammatory cells. The histometric analysis showed that the total amount of mononuclear inflammatory cells labeled did not differ significantly between smokers and non-smokers (p> 0.05). Evaluating each cell type separately, significant differences were not detected between groups (p> 0.05). When stratifying the samples into regions (coronal, middle and apical third) to evaluate the presence of individual cell types in each region significant differences between the groups were not detected (p> 0.05). The zymography of the samples suggested that the expression of MMP-2 and 9 showed no statistically significant differences between the two groups (p> 0.05). Thus, within the limits of this study, we can conclude that sites with chronic periodontitis in smokers and non-smokers did not differ in the amount of mononuclear inflammatory cells and in the expression of MMPs 2 and 9. / O estudo teve como objetivo a avaliação imunoistoquímica da proporção de células mononucleares e da expressão zimográfica da MMP-2 e 9 na periodontite crônica em fumantes e não-fumantes. Foram examinados 127 pacientes dos quais 31 preencheram os critérios de inclusão e foram inseridos no estudo, sendo 16 não-fumantes e 15 fumantes. Estes pacientes foram operados e 31 biópsias foram coletadas de área interproximal de dentes com bolsa periodontal >5mm e divididas longitudinalmente em duas partes, uma para análise histológica e outra para zimografia. As amostras foram processadas histologicamente e expostas aos anticorpos monoclonais para células B (anti-CD20), células T de memória (anti-CD45RO) e monócitos ou macrófagos (anti-CD68). De maneira geral, as amostras apresentaram padrão semelhante, com um tecido conjuntivo subjacente ao epitélio oral rico em células inflamatórias. A análise histométrica demonstrou que a quantidade total de células inflamatórias mononucleares marcadas não diferiu entre fumantes e não-fumantes (p>0,05). Ao avaliar cada tipo celular separadamente, também não foram detectadas diferenças estatisticamente significativas entre os grupos (p>0,05). Ao dividir as amostras em regiões (terço coronal, médio e apical) e avaliar a presença de cada tipo celular em cada uma das regiões também não foram detectadas diferenças estatísticas significantes entre os grupos (p>0,05). A avaliação das zimografias sugere que a expressão de MMP-2 e 9 não apresentaram diferenças estatisticamente significantes entre os dois grupos (p>0,05). Assim, dentro dos limites deste estudo, pode-se concluir que os sítios com periodontite crônica de fumantes e não-fumantes não diferem em relação à quantidade e localização de células inflamatórias mononucleares e na expressão de MMPs 2 e 9.
165

Nuclear and Molecular Imaging Modalities for Predicting Calcific Aortic Valve Disease Progression in Animal Models

Farber, Gedaliah 07 July 2020 (has links)
Introduction and Objectives Calcific aortic valve disease (CAVD) is the most common valvular disease, accounting for 50% of all valve disorders and is the third most common cardiovascular disease following coronary disease and hypertension.[1,2] Currently, there is no pharmacological agent capable of reversing or slowing down the progression of CAVD and treatment of severe cases consists of surgical repair or valve replacement[2]. Hence, there is a crucial need for earlier detection using predictive biomarkers that will allow for preventative intervention as opposed to post-symptomatic disease treatment or management. Namely, one target of particular interest is the expression of matrix metalloproteinases (MMPs) (specifically MMP-1, -2, and -9) which are upregulated in CAVD prior to calcification events and have been previously shown to serve as an attractive molecular imaging target.1–3 The primary objective of this study is to assess the feasibility of detecting biomarkers of CAVD by various in vivo imaging modalities, such as PET and echocardiography. In addition, this study assesses disease progression in various mouse strains to qualify an appropriate CAVD animal model. Methods In vivo and ex vivo imaging of C57Bl/6 and ApoE-/- (n = 8 per strain cohort) mouse models are used to link unique features of matrix remodelling with CAVD progression. At baseline and longitudinal follow-up (4, 8, and 12 months), in vivo hemodynamic impairment is assessed through echocardiography, and calcification and MMP activity are measured using PET with a series of radiotracers: [18F]NaF for calcification, [18F]BR351 for the molecular targets of MMP-2 and -9, and [18F]FMBP with molecular target specificity for MMP-13. Following imaging, aortic valve (AV) tissue is harvested, sectioned, and analyzed for calcification, inflammatory markers, collagen types, and MMP activity in AV leaflets. Tracer autoradiography, immunofluorescence, and in situ zymography are used to confirm in vivo imaging results with improved resolution and quantification in valves. Histological sample preparation, experimentation, and analyses are then repeated in human AV tissue samples for relative comparison of biomarker expression in animal models. Results Echocardiography suggests positive signs of disease progression in experimental animal models. In comparison to WT, ApoE-/- mice show: increased peak velocity (p<0.0001), decreased aortic valve area (p<0.001), and irregular valve dynamics. [18F]NaF PET imaging shows expected bone uptake and low calcium-burden in young and WT animals. [18F]FMBP shows increased uptake in the valve area of diseased models at later timepoints, 1.530 compared to <0.001 %ID/g (p<0.005), in disease vs control animals respectively. Furthermore, confirmation of sought-after biomarkers has also been assessed by analysis of various histological sample preparations including the presence of leaflet calcification, upregulation of MMP-2, -9, and -13, matrix remodelling, lipids, inflammatory markers, and activated MMP expression. Conclusion Findings from this study suggest that molecular imaging techniques using target-specific radiotracers, as well as echocardiography for assessment of hemodynamic impairment, are feasible solutions in predicting disease onset in CAVD specific animal models.
166

Estudo da pele do campo cancerizável antes e após a terapia fotodinâmica através dos métodos clínicos, histopatológicos e imunohistoquímicos / Clinical, histopathological and immunohistochemical assessment of human skin field cancerization before and after photodynamic therapy

Torezan, Luís Antonio Ribeiro 16 November 2011 (has links)
O conceito de campo de cancerização, em dermatologia, sugere que a pele fotodanificada tem maior potencial para o desenvolvimento de neoplasias cutâneas. A terapia fotodinâmica (TFD) é um método não invasivo para o tratamento de queratoses actínicas (QA) múltiplas, possibilitando a abordagem de todo o campo. Vinte e seis pacientes com múltiplas QAs na face foram submetidos a três sessões de TFD com metilaminolevulinato 16% (MAL) e luz vermelha, com intervalo de um mês. Biópsias foram realizadas antes e após três meses da última sessão e o material corado para hematoxilina-eosina e Weigert. O estudo imunohistoquímico foi feito para os marcadores: TP-53, pró-colageno I, Metaloproteinase-1 e Tenascina-C. A avaliação do fotoenvelhecimento global melhorou consideravelmente (p < 0,001) e a cura clínica das QAs foi de 89,5% ao final do estudo. Duas sessões mostraram ser equivalentes a três sessões de TFD. Diminuição significante do grau e extensão da atipia celular (p < 0,001), aumento das fibras colágenas (p = 0,001) e melhora do grau de elastose (p = 0,002) foram observadas. O estudo imunohistoquímico mostrou diminuição da expressão da TP-53 (p = 0,580), aumento de pró-colágeno I (p = 0,477) e de MMP-1 (p = 0,08), embora não houvesse diferença estatisticamente significante. Aumento significativo foi observado para Tenascina-C (p = 0,024). Múltiplas sessões de TFD com MAL induziram melhora clínica e histológica do campo de cancerização. A diminuição da severidade e extensão da atipia celular associada à menor expressão de TP-53 sugerem redução do potencial carcinogênico do campo / The field cancerization concept suggests that photodamaged skin has an increased risk for the development of malignant lesions. Topical photodynamic therapy (PDT) is a non-invasive therapeutic method for multiple actinic keratosis (AK), allowing the possibility of treating the entire surface. Twenty-six patients with photodamaged skin and multiple AKs on the face were submitted to three consecutive sessions of PDT with mehtylaminolevulinate 16% (MAL) and red light, one month apart. Biopsies were performed before and three months after the last treatment session, and stained for hematoxilin-eosin and Weigert. Immunohistochemestry study was performed for TP-53, pro-collagen I, Metalloproteinase-1 and Tenascin-C. The global score for photodamage improved considerably in all patients (p < 0.001). The AK clearance rate was 89.5% at the end of the study. Two treatments were similar to three MAL-PDT sessions. A significant decrease in keratinocytes atypia grade and amount was observed (p < 0.001). A significant increase in collagen deposition (p = 0.001) and improvement of solar elastosis (p = 0.002) were noticed. Immunohistochemical study showed decreased TP-53 expression although not statistically significant (p = 0.580), increased pro-collagen I and MMP-1 expressions (p = 0.477 and p = 0.08) again not statistically significant and a increased expression of Tenascin-C (p = 0.024), which was statistically significant. In conclusion, multiple sessions of MAL-PDT induced clinical and histological improvement of field cancerization. The decrease in severity and extension of keratinocytes atypia associated with a decreased expression of TP-53 suggest a reduced carcinogenic potential of the altered field
167

Role of Tissue Microenvironment in Recruiting Macrophages During Apoptosis-induced Proliferation

Diwanji, Neha 12 May 2020 (has links)
Apoptosis-induced compensatory proliferation (AiP) is a mechanism that maintains tissue homeostasis after stress-induced cell death. During AiP, apoptotic cells induce proliferation of the neighboring surviving cells to compensate for tissue loss. AiP is important for wound healing and tissue regeneration in several model organisms. Additionally, AiP is an important feature of tumorigenesis and tumor relapse as it contributes to tumor repopulation following radiation or chemotherapy. Using an overgrowth tumor model (“undead tissue”) in Drosophila melanogaster, we determined that the initiator caspase Dronc promotes generation of extracellular Reactive Oxygen Species (ROS), which drive activation of the stress kinase JNK and downstream mitogens to promote AiP. We also observed increased numbers of Drosophila macrophages, termed hemocytes, which are attracted to undead tissue. However, the specific mechanisms by which macrophages are recruited to undead tissue are still unclear. Here, we report that the tissue microenvironment of the overgrown undead tissue directs macrophage recruitment during AiP. We demonstrate that ROS, JNK, and the matrix metalloproteinase Mmp2 are important for recruiting macrophages. Mechanistically, undead tissue-produced ROS and active JNK damage the basement membrane (BM) surrounding the undead tissue, by upregulating the expression and activity of Mmp2. The damaged BM then recruits macrophages to the undead tissue. Taken together, we propose a model in which the ROS-JNK-Mmp2 signaling axis damages the BM of undead tissue, resulting in changes in the tissue microenvironment that recruit macrophages to the area of damage to promote AiP and overgrowth.
168

Role of Type 2 Cannabinoid Receptor (CB2) in Atherosclerosis.

Netherland, Courtney Denise 17 December 2011 (has links) (PDF)
Atherosclerosis is a macrophage-dominated nonresolving inflammatory disease of the arterial wall. Macrophage processes, including apoptosis, influence lesion development in atherosclerosis. Cannabinoids, compounds structurally related to Δ9-tetrahydrocannabinol (THC), the active ingredient in marijuana, exert their effects through cannabinoid receptors, CB1 and CB2. Cannabinoid treatment, THC or Win55,212-2, reduces atherosclerosis in ApoE-null mice by a mechanism thought to involve CB2. However, the exact role of CB2 in atherosclerosis remains unclear. We found that CB2-null macrophages are resistant to oxysterol/oxLDL-induced apoptosis leading us to hypothesize that CB2 may modulate macrophage apoptosis in atherosclerosis. To determine the functions of CB2 in atherosclerosis, we fed low density lipoprotein receptor-null (Ldlr-/-) and Ldlr-/- mice genetically deficient in CB2, an atherogenic diet for 8 and 12 weeks. CB2 deficiency did not significantly affect aortic root lesion area after 8 or 12 weeks; however, after 12 weeks, CB2-deficient lesions displayed increased lesional macrophage and smooth muscle cell (SMC) content and a ~2-fold reduction in lesional apoptosis. CB2-deficienct lesions also displayed reduced collagen content and elevated elastin fiber fragmentation that was associated with elevated levels of the extracellular matrix degrading enzyme, matrix metalloproteinase 9 (MMP9). These results demonstrate that although CB2 signaling does not affect atherosclerotic lesion size it does modulate lesional apoptosis, cellularity and ECM composition. Ldlr-/- and CB2-deficient Ldlr-/- mice were also subjected to daily treatments with Win55,212-2, a synthetic cannabinoid, over the last 2 weeks of an 8 week atherogenic diet to identify CB2-dependent and CB2-independent effects of cannabinoid receptor stimulation on atherosclerosis. Win55,212-2 did not affect hypercholesterolemia, aortic root lesion area, lesional macrophage infiltration, or ECM composition in either genotype but did significantly reduce total plasma triglyceride levels and lesional SMC content, independent of CB2. Surprisingly, lesional apoptosis was dose-dependently repressed by Win55,212-2 in Ldlr-/- mice by a CB2-dependent mechanism. All together, these results support the suggestion that CB2 may be a target for novel therapies aimed at modulating lesional apoptosis and cellularity to increase lesion stability and reduce the vulnerability to rupture.
169

The role of MMP10 in non-small cell Lung cancer, and pharmacological evaluation of its potential as a target for therapeutic intervention. Investigation of the role of MMP10 in the tumour microenvironment of non-small cell lung cancer using gene, protein and mass spectrometry approaches to determine MMP10’s potential in drug development strategies

Bin Saeedan, Abdulaziz S.A. January 2014 (has links)
Non-Small Cell Lung Cancer (NSCLC), which accounts for 80% of all lung cancer cases, is associated with resistance to chemotherapy and poor prognosis. Exploitation of NSCLC-upregulated pathways that can either be targeted by novel therapeutics or used to improve the tumour-delivery of current chemotherapeutics are required. Among the matrix metalloproteinases (MMPs) that are essential for tumour development, MMP10 is a potential candidate as a therapeutic target based on its expression and contribution to NSCLC development. This research aims to explore the expression and functions of MMP10 in the tumour microenvironment of NSCLC and evaluate the potential of MMP10 as a target for therapeutic intervention. Herein, MMP10 expression at gene and protein levels were analysed in a panel of NSCLC cell lines using RT-PCR and Western blotting analysis. To determine MMP10 functional relevance, an in vitro angiogenesis assay using cell conditioned media was carried out. To identify specific peptide sequences for the design of prodrugs rationalised to be MMP10 activated, in vitro substrate cleavage studies were performed using a mass spectrometry approach to differentiate between MMP10 and the structurally similar MMP3. This study demonstrates that MMP10 is highly expressed in NSCLC and that high levels of MMP10 are associated with induction of angiogenesis, a crucial process supporting tumour growth. In addition to the achievement of having been able to differentiate between closely similar MMP3 and MMP10 through carefully monitoring the hydrolysis rate of compound 444259 (a known MMP substrate), data generated herein provides the basis for further studies to exploit MMP10 as a prodrug-activator. / Full text was made available at the end of the embargo period, 12th Dec 2019
170

Immunohistochemical Demonstration of the pGlu79 α-Synuclein Fragment in Alzheimer’s Disease and Its Tg2576 Mouse Model

Bluhm, Alexandra, Schrempel, Sarah, Schilling, Stephan, von Hörsten, Stephan, Schulze, Anja, Roßner, Steffen, Hartlage-Rübsamen, Maike 03 November 2023 (has links)
The deposition of β-amyloid peptides and of α-synuclein proteins is a neuropathological hallmark in the brains of Alzheimer’s disease (AD) and Parkinson’s disease (PD) subjects, respectively. However, there is accumulative evidence that both proteins are not exclusive for their clinical entity but instead co-exist and interact with each other. Here, we investigated the presence of a newly identified, pyroglutamate79-modified α-synuclein variant (pGlu79-aSyn)—along with the enzyme matrix metalloproteinase-3 (MMP-3) and glutaminyl cyclase (QC) implicated in its formation—in AD and in the transgenic Tg2576 AD mouse model. In the human brain, pGlu79-aSyn was detected in cortical pyramidal neurons, with more distinct labeling in AD compared to control brain tissue. Using immunohistochemical double and triple labelings and confocal laser scanning microscopy, we demonstrate an association of pGlu79-aSyn, MMP-3 and QC with β-amyloid plaques. In addition, pGlu79-aSyn and QC were present in amyloid plaque-associated reactive astrocytes that were also immunoreactive for the chaperone heat shock protein 27 (HSP27). Our data are consistent for the transgenic mouse model and the human clinical condition. We conclude that pGlu79-aSyn can be generated extracellularly or within reactive astrocytes, accumulates in proximity to β-amyloid plaques and induces an astrocytic protein unfolding mechanism involving HSP27.

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