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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.
21

T1α/Podoplanin Shows Raft-Associated Distribution in Mouse Lung Alveolar Epithelial E10 Cells

Barth, Kathrin, Bläsche, Robert, Kasper, Michael January 2010 (has links)
Aims: T1α/(podoplanin) is abundantly expressed in the alveolar epithelial type I cells (ATI) of rodent and human lungs. Caveolin-1 is a classical primary structural protein of plasmalemal invaginations, so-called caveolae, which represent specialized lipid rafts, and which are particularly abundant in ATI cells. The biological functions of T1α in the alveolar epithelium are unknown. Here we report on the characteristics of raft domains in the microplicae/microvillar protrusions of ATI cells, which contain T1α. Methods: Detergent resistant membranes (DRMs) from cell lysates of the mouse epithelial ATI-like cell line E10 were prepared using different detergents followed by flotation in a sucrose gradient and tested by Western and dot blots with raft markers (caveolin-1, GM1) and nonraft markers (transferrin receptor, PDI and β-Cop). Immunocytochemistry was employed for the localization of T1α in E10 cells and in situ in rat lungs. Results: Our biochemical results showed that the solubility or insolubility of T1α and caveolin-1 differs in Triton X-100 and Lubrol WX, two distinct non-ionic detergents. Caveolin-1 was unsoluble in both detergents, whereas T1α was Triton X-100 soluble but Lubrol WX insoluble. Immunofluorescence double stainings revealed that both proteins were colocalized with GM1, while caveolin-1 and T1α were not colocalized in the plasma membrane. Cholesterol depletion modified the segregation of T1α in Lubrol WX DRMs. Cellular processes in ultrathin sections of cultured mouse E10 cells were immunogold positive. Immunoelectron microscopy (postembedding) of rat lung tissue revealed the preferential localization of T1α on apical microvillar protrusions of ATI cells. Conclusion: We conclude that T1α and caveolin-1 are located in distinct plasma membrane microdomains, which differ in their protein-lipid interactions. The raft-associated distribution of T1α may have an impact on a specific, not yet clarified function of this protein in the alveolar epithelium. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
22

Valor prognóstico da microdensidade vascular linfática intratumoral e da expressão neoplásica de podoplanina em carcinomas escamosos vulvares / Prognostic value of intratumoral microvessel lymphatic densityand of podoplanin neoplastic expression in squamous vulvar carcinomas

Renata Sampaio Góes 19 December 2012 (has links)
Introdução: Os carcinomas vulvares são tumores raros com morbidade elevada associada ao tratamento cirúrgico padrão e altos índices de recorrência loco-regional. Os vasos linfáticos são importantes vias de disseminação regional e o estado linfonodal é o principal indicador prognóstico. A densidade linfática do tumor, assim como moléculas relacionadas à linfangiogênese tem sido avaliadas em vários tumores para prever metástase linfonodal e para identificar possíveis alvos terapêuticos. Entre as moléculas relacionadas ao controle da linfangiogênese destaca-se a podoplanina, cuja expressão por células neoplásicas de tipo escamoso pode inibir a disseminação linfática. Não identificamos até o momento nenhum estudo que tenha avaliado o papel da densidade de vasos linfáticos intratumorais ou da expressão de podoplanina pelas células neoplásicas no comportamento de carcinomas escamosos vulvares. Objetivos: Nossos objetivos foram estudar a densidade intratumoral dos vasos linfáticos (DVL) e a expressão de podoplanina pelas células neoplásicas em carcinomas escamosos vulvares no sentido de determinar sua relação com o desfecho e fatores prognósticos clássicos, incluindo metástase linfonodal. Métodos: Selecionamos 35 pacientes com carcinoma de células escamosas vulvares submetidas à tratamento cirúrgico primário incluindo vulvectomia e dissecção regional de nódulos linfáticos. Após revisão dos dados dos prontuários médicos (idade da paciente, estadiamento, tipo de tratamento e tamanho do tumor), todas as lâminas foram reexaminadas para determinar o grau histológico, invasão linfática peritumoral e profundidade da infiltração. Foram selecionadas áreas do tumor para a construção de blocos de parafina com microarranjos de tecidos e identificação imunoistoquímica de podoplanina pelo anticorpo D2-40. A DVL intratumoral foi quantificada pela contagem de vasos marcados nas áreas de maior densidade. O número de vasos foi contado em 10 campos microscópicos de grande aumento e a média foi o valor atribuído para a DVL em cada caso. A expressão de podoplanina pelas células neoplásicas foi considerada positiva quando mais de 10% das células apresentaram coloração citoplasmática de intensidade moderada a intensa. Investigamos a associação das duas variáveis com as características prognósticas clássicas (idade, estadiamento, tamanho do tumor, grau histológico, embolização vascular peritumoral, nível de infiltração do tumor, comprometimento linfonodal), assim como sua associação com desfecho. Resultados: Valores mais elevados de DVL intratumoral foram identificados em tumores de baixo grau, em estádios iniciais, em tumores sem invasão linfática e naqueles com menor infiltração estromal. Na análise univariada, DVL intratumoral elevada foi associada a maior sobrevida geral . A expressão de podoplanina pelas células neoplásicas não se relacionou a nenhuma das variáveis prognósticas, comprometimento linfonodal ou sobrevida, assim como não se associou à DVL. Conclusões: A DVL intratumoral em carcinomas escamosos vulvares associa-se a características prognósticas favoráveis. Já a expressão de podoplanina pelas células neoplásicas não parece interferir na apresentação e comportamento destes carcinomas. / Introduction: Vulvar carcinomas are rare tumors presenting high morbidity associated to the standard surgical treatment and high rates of locoregional recurrence. Lymphatic vessels serves as major routes for regional dissemination and the lymph node status is the main prognostic indicator. Tumor lymphatic density as well as lymphangiogenesis-related molecules has being studied in various tumors in order to predict lymph node metastasis and to identify a possible candidate to target therapy. Among the molecules related to lymphangiogenesis in the group of squamous cell carcinomas podoplanin expression by neoplastic cells emerges as an inhibitor of lymphatic dissemination. To our knowledge, no study evaluated the role of intratumoral lymphatic vessels or podoplanin expression by neoplastic cells in the behavior of vulvar squamous carcinomas. Objectives: Our aims were to study the intratumoral lymphatic vessel density (LVD) and podoplanin expression by neoplastic cells in vulvar squamous carcinoma according their relationship with outcome and classical prognostic factors, including lymph node metastasis. Methods: We selected 35 cases of patients with vulvar squamous cell carcinoma submitted to primary surgical treatment that included vulvectomy and regional lymph nodes dissection. After revision of medical records data (age of patient, stage, type of surgery and tumor size), all the slides were reviewed to achieve histological grade, peritumoral lymphatic invasion and depth of infiltration. Areas of the tumor were selected to construction of tissue microarrays paraffin blocs and immunohistochemical identification of podoplanin by the D2-40 antibody. Intratumoral LVD was quantified by counting the stained vessels in hotspots areas. The number of vessels was counted in 10 high power microscopic fields and the mean was the value of the LVD for each case. Podoplanin expression by neoplastic cells was considered positive when more than 10% of the cells showed moderate to strong cytoplasmatic stained. We investigated the association of the two variables with classical prognostic features (age of patient, stage, tumor size, histologic grade, vascular involvement, depth of infiltration, lymph node involvement as well outcome. Results: Higher values of intratumoral LVD were identified in low grade and low stage tumors, in tumors without lymphatic invasion and those with lesser stromal infiltration. In univariate analysis, high intratumoral LVD was associated to higher overall survival. Podoplanin expression by neoplastic cells did not show association with any of the prognostic variable, nor with lymph node involvement or outcome. Conclusions: Intratumoral LVD in vulvar squamous carcinoma is associated with prognostic favorable features. On the other hand, podoplanin expression by neoplastic cells did not seem to influence the behavior of these carcinomas
23

Valor prognóstico da microdensidade vascular linfática intratumoral e da expressão neoplásica de podoplanina em carcinomas escamosos vulvares / Prognostic value of intratumoral microvessel lymphatic densityand of podoplanin neoplastic expression in squamous vulvar carcinomas

Góes, Renata Sampaio 19 December 2012 (has links)
Introdução: Os carcinomas vulvares são tumores raros com morbidade elevada associada ao tratamento cirúrgico padrão e altos índices de recorrência loco-regional. Os vasos linfáticos são importantes vias de disseminação regional e o estado linfonodal é o principal indicador prognóstico. A densidade linfática do tumor, assim como moléculas relacionadas à linfangiogênese tem sido avaliadas em vários tumores para prever metástase linfonodal e para identificar possíveis alvos terapêuticos. Entre as moléculas relacionadas ao controle da linfangiogênese destaca-se a podoplanina, cuja expressão por células neoplásicas de tipo escamoso pode inibir a disseminação linfática. Não identificamos até o momento nenhum estudo que tenha avaliado o papel da densidade de vasos linfáticos intratumorais ou da expressão de podoplanina pelas células neoplásicas no comportamento de carcinomas escamosos vulvares. Objetivos: Nossos objetivos foram estudar a densidade intratumoral dos vasos linfáticos (DVL) e a expressão de podoplanina pelas células neoplásicas em carcinomas escamosos vulvares no sentido de determinar sua relação com o desfecho e fatores prognósticos clássicos, incluindo metástase linfonodal. Métodos: Selecionamos 35 pacientes com carcinoma de células escamosas vulvares submetidas à tratamento cirúrgico primário incluindo vulvectomia e dissecção regional de nódulos linfáticos. Após revisão dos dados dos prontuários médicos (idade da paciente, estadiamento, tipo de tratamento e tamanho do tumor), todas as lâminas foram reexaminadas para determinar o grau histológico, invasão linfática peritumoral e profundidade da infiltração. Foram selecionadas áreas do tumor para a construção de blocos de parafina com microarranjos de tecidos e identificação imunoistoquímica de podoplanina pelo anticorpo D2-40. A DVL intratumoral foi quantificada pela contagem de vasos marcados nas áreas de maior densidade. O número de vasos foi contado em 10 campos microscópicos de grande aumento e a média foi o valor atribuído para a DVL em cada caso. A expressão de podoplanina pelas células neoplásicas foi considerada positiva quando mais de 10% das células apresentaram coloração citoplasmática de intensidade moderada a intensa. Investigamos a associação das duas variáveis com as características prognósticas clássicas (idade, estadiamento, tamanho do tumor, grau histológico, embolização vascular peritumoral, nível de infiltração do tumor, comprometimento linfonodal), assim como sua associação com desfecho. Resultados: Valores mais elevados de DVL intratumoral foram identificados em tumores de baixo grau, em estádios iniciais, em tumores sem invasão linfática e naqueles com menor infiltração estromal. Na análise univariada, DVL intratumoral elevada foi associada a maior sobrevida geral . A expressão de podoplanina pelas células neoplásicas não se relacionou a nenhuma das variáveis prognósticas, comprometimento linfonodal ou sobrevida, assim como não se associou à DVL. Conclusões: A DVL intratumoral em carcinomas escamosos vulvares associa-se a características prognósticas favoráveis. Já a expressão de podoplanina pelas células neoplásicas não parece interferir na apresentação e comportamento destes carcinomas. / Introduction: Vulvar carcinomas are rare tumors presenting high morbidity associated to the standard surgical treatment and high rates of locoregional recurrence. Lymphatic vessels serves as major routes for regional dissemination and the lymph node status is the main prognostic indicator. Tumor lymphatic density as well as lymphangiogenesis-related molecules has being studied in various tumors in order to predict lymph node metastasis and to identify a possible candidate to target therapy. Among the molecules related to lymphangiogenesis in the group of squamous cell carcinomas podoplanin expression by neoplastic cells emerges as an inhibitor of lymphatic dissemination. To our knowledge, no study evaluated the role of intratumoral lymphatic vessels or podoplanin expression by neoplastic cells in the behavior of vulvar squamous carcinomas. Objectives: Our aims were to study the intratumoral lymphatic vessel density (LVD) and podoplanin expression by neoplastic cells in vulvar squamous carcinoma according their relationship with outcome and classical prognostic factors, including lymph node metastasis. Methods: We selected 35 cases of patients with vulvar squamous cell carcinoma submitted to primary surgical treatment that included vulvectomy and regional lymph nodes dissection. After revision of medical records data (age of patient, stage, type of surgery and tumor size), all the slides were reviewed to achieve histological grade, peritumoral lymphatic invasion and depth of infiltration. Areas of the tumor were selected to construction of tissue microarrays paraffin blocs and immunohistochemical identification of podoplanin by the D2-40 antibody. Intratumoral LVD was quantified by counting the stained vessels in hotspots areas. The number of vessels was counted in 10 high power microscopic fields and the mean was the value of the LVD for each case. Podoplanin expression by neoplastic cells was considered positive when more than 10% of the cells showed moderate to strong cytoplasmatic stained. We investigated the association of the two variables with classical prognostic features (age of patient, stage, tumor size, histologic grade, vascular involvement, depth of infiltration, lymph node involvement as well outcome. Results: Higher values of intratumoral LVD were identified in low grade and low stage tumors, in tumors without lymphatic invasion and those with lesser stromal infiltration. In univariate analysis, high intratumoral LVD was associated to higher overall survival. Podoplanin expression by neoplastic cells did not show association with any of the prognostic variable, nor with lymph node involvement or outcome. Conclusions: Intratumoral LVD in vulvar squamous carcinoma is associated with prognostic favorable features. On the other hand, podoplanin expression by neoplastic cells did not seem to influence the behavior of these carcinomas
24

Rôle de la Podoplanine dans le développement et la tumorigenèse mammaires / Role of Podoplanin in mammary gland development and tumorigenesis

Bresson, Laura 21 November 2017 (has links)
L’épithélium mammaire est composé de cellules luminales et basales myoépithéliales. Il comprend des cellules souches et progénitrices qui gouvernent le développement de la glande. Leur dérégulation est probablement à l’origine de certains cancers du sein très agressifs, dits « triple-­‐négatifs » (négatifs pour les récepteurs hormonaux et HER2), pour lesquels il n’existe pas de thérapie ciblée. L’équipe a identifié un nouveau marqueur spécifique du compartiment basal comprenant les cellules souches, la Podoplanine (Pdpn), dont l’expression est concentrée aux contactsintercellulaires basal-­‐luminal. La Pdpn est une glycoprotéine transmembranaire connectée au cytosquelette, impliquée dans le développement denombreux tissus et la tumorigenèse. Son rôle dans la glande mammaire n’a jamais été étudié. A l’aide d’une délétion génique conditionnelle, nous avons trouvé que l’absence de Pdpn dans l’épithélium mammaire perturbe la fonction des cellules souches/progénitrices basales ainsi quel’expression de plusieurs composants du signalosome de la voie Wnt/b-­‐caténine. De plus, la perte de Pdpn dans un modèle murin de tumorigénèsemammaire induite par l’activation de la signalisation Wnt/b-­‐caténine réduit la fréquence des tumeurs mammaires triple-­‐négatives, limite l’expansiondes cellules initiatrices de tumeurs et favorise l’expression de marqueurs moléculaires associés à un programme de transition mésenchymo-­‐épithéliale. Au moyen d’expériences de gain de fonction dans une lignée de cellules basales mammaires, Nous avons montré que les phénotypes décrits précédemment reposent sur des mécanismes moléculaires impliquant la Pdpn dans le contrôle positif de l’activation de la voie Wnt/b-­‐caténine. Notre étude révèle un rôle pour la Pdpn dans le contrôle des cellules souches et de leur réponse à la signalisation Wnt/b-­‐caténine au cours du développement et de la tumorigénèse mammaire. / Stem cells (SC) drive mammary development, giving rise postnatally to an epithelial bilayer composed of luminal and basal myoepithelial cells. The molecular identity of SCs and the factors regulating their function remain poorly defined. We identified the transmembrane protein, Podoplanin (Pdpn), as a specific marker of the basal compartment, including multipotent SCs, and found Pdpn localized at the basal-luminal interface. Embryonic deletion of Pdpn targeted to basal cells diminished basal and luminal SC activity and affected expression of several Wnt/b-catenin (Wnt/b-cat) signaling components. Moreover, Pdpn deletion attenuated mammary tumor formation in a mouse model of b-cat-induced breast cancer, limiting tumor-initiating cell expansion and promoting molecular features associated with mesenchymal-to-epithelial cell transition. In line with the loss-of-function data, we demonstrated that mechanistically, Pdpn enhanced Wnt/b-cat signaling in mammary basal cells. Overall, our study reveals a role for Pdpn in mammary development and tumorigenesis through the control of Wnt/b-cat-responsive SCs.
25

Kidney Hyaluronan : Regulatory Aspects During Different States of Body Hydration, Nephrogenesis & Diabetes

Rügheimer, Louise January 2008 (has links)
<p>The kidney regulates the excretion of water and electrolytes, which maintains homeostasis and enables control of arterial blood pressure. Hyaluronan, a large negatively charged interstitial glucosaminoglycan, is heterogeneously distributed within the kidney, primarily found in the medulla.</p><p>Medullary hyaluronan content changes depending on the state of body hydration and plays a part in fluid regulation through its water binding and viscoelastic properties. </p><p>The aim of this thesis was to provide new insight into the regulation of intrarenal hyaluronan during different states of body hydration, during completion of kidney development, and during diabetes mellitus.</p><p>Dehydration reduces medullary interstitial hyaluronan in parallel with reduced hyaluronan synthase 2 gene expression and increased urinary hyaluronidase activity. Acute hydration results in an increase in medullary hyaluronan, an increase that requires nitric oxide and prostaglandins. Urinary hyaluronidase activity decreases during hydration. The elevation of hyaluronan is important for reducing water permeability of the interstitium i.e. favoring diuresis.</p><p>Changes in hyaluronan concentration constitute a morphoregulatory pathway that plays a key role in nephrogenesis. The reduction in neonatal hyaluronan depended on an angiotensin II mediated process that does not appear dependent on lymph vessel formation. If angiotensin II is blocked with an ACE inhibitor, hyaluronan accumulates, which results in structural and functional abnormalities in the kidney. </p><p>Renomedullary hyaluronan is elevated during uncontrolled diabetes, which coincides with induction of hyaluronan synthase 2 mRNA, hyperglycemia, glucosuria, proteinuria and overt diuresis. The levels of hyaluronan are probably at a <i>terminus ad quem</i> as no further response was seen during hydration. The higher interstitial expression of hyaluronan during diabetes may be involved in the progression of diabetic nephropathy.</p><p>This thesis in physiology provides new mechanistic insights into the regulation of renal hyaluronan during various aspects of fluid handling.</p>
26

Avaliação da linfangiogênese intratumoral em carcinoma precoce do colo de útero / Evaluation of intratumoral lymphangiogenesis in early-stage carcinoma of the uterine cervix

Zaganelli, Fabrícia Leal 10 August 2010 (has links)
A incidência do câncer cervical permanece elevada em nosso país, provavelmente devido ao rastreamento ser realizado principalmente em áreas urbanas e haver áreas menos favorecidas onde os programas de rastreamento não são efetivos. É bem sabido que a mortalidade pelo câncer raramente é devida ao tumor primário, mas à disseminação metastática das células tumorais em órgãos distantes. A via linfática é considerada a preferencial para disseminação metastática nos tumores ginecológicos. E o estágio clínico e os linfonodos regionais são considerados os fatores prognósticos mais potentes no carcinoma de colo útero. A compreensão da linfangiogênese pode ser considerada uma importante chave na elucidação dos mecanismos usados pelas células tumorais na sua disseminação. Os objetivos do presente estudo são avaliar as características clínico-patológicas do câncer do colo do útero e sua associação com o comprometimento linfonodal e o desfecho; avaliar a linfangiogênese intratumoral pela análise quantitativa da microdensidade vascular linfática (MDVL), usando o método imunoistoquímico para marcação dos vasos linfáticos e três métodos morfométricos para a quantificação; determinar a associação entre a MDVL, características clínico-patológicas de apresentação, comprometimento linfonodal, desfecho e a expressão de podoplanina em células neoplásicas e a expressão da podoplanina em células fibroblásticas do estroma intratumoral. Os estudos sobre a MLVD em câncer de colo de útero são raros e controversos. Nossos resultados demonstraram que a MLVD foi mais acentuada nos tumores de menor tamanho (<2 cm), nos estádios iniciais (IB1), com menos infiltrações, sem comprometimento vascular e sem comprometimento linfonodal, provavelmente porque a indução da linfangiogênese pode ser um evento inicial na progressão do câncer, quando ainda nem todos os vasos neoformados estão funcionantes ou patentes. Isto explicaria a elevada MLVD nos tumores iniciais quando os linfonodos estavam frequentemente negativos. Observou-se que não não houve associação significativa entre expressão de podoplanina em células neoplásicas e comprometimento vascular, comprometimento dos linfonodos ou desfecho. A expressão de podoplanina em fibroblastos do estroma intratumoral no câncer precoce de colo de útero está associada a melhor prognóstico. Até o presente, acreditase que este seja o primeiro estudo a investigar o papel da expressão da podoplanina no estroma intratumoral de carcinoma precoce do colo do útero, relacionando-a com MLVD, comprometimento dos linfonodos e o desfecho / Cervix carcinoma incidence remains still high in our country, probably as the screening occurrence is carried out mainly in the urban areas and there are less favored areas where the screening programs are not effective. It is well known that the cancer mortality is rarely caused by the primary tumor, but it is caused by the metastatic spread of tumor cells in distant organs. The lymphatic route is considered the choice for the metastatic dissemination in the gynecological tumors. And the clinical stage and the regional lymphonodes are considered the most powerful prognostic factors in the uterine cervix cancer. The understanding of the lymphangiogenesis can be considered an important key for the elucidation of the mechanisms used in the tumor cells dissemination. The current study objectives are to evaluate the clinic-pathological characteristics of the uterine cervix carcinoma and its association with the lymphnodal involvement and outcome; to evaluate the intratumoral lymphangiogenesis by the quantitative analysis of the lymphatic vessel micro density (LVMD), using the immunoistochemical method for marking the lymphatic vessels and three morphometric methods for the quantification. To determine the association between the LVMD, the clinicpathological characteristics, the lymphonodal involvement and outcome and the podoplanin expression in neoplasic cells and in fibroblastic cells of the intratumoral stroma. Studies about the LVDM in uterine cervical cancer are rare and controversial. Our results demonstrated that the LVDM was more remarkable in the smaller tumors(<2cm), in the initial stages (IB1), with less infiltrations, with no vascular involvement and no lymphnodal involvement. Probably because the induction of lymphangiogenesis may be an early event in cancer progression, while still not all the newly formed vessels are functioning or patent. This would explain the high LVMD in the initial tumors while the lymphonodes were frequently negative. It was noted that there were no significant association between podoplanin expression in neoplasic cells and vessel involvement, lymphonodes involvement or outcome. Podoplanin expression in fibroblasts of the intratumoral stroma in early cervix carcinoma was associated to better prognosis. To date, it is believed that this is the first study to investigate the role of podoplanin expression in intratumoral stroma of cervix carcinoma, relating it to LVMD, lymph node involvement and outcome
27

Avaliação da linfangiogênese intratumoral em carcinoma precoce do colo de útero / Evaluation of intratumoral lymphangiogenesis in early-stage carcinoma of the uterine cervix

Fabrícia Leal Zaganelli 10 August 2010 (has links)
A incidência do câncer cervical permanece elevada em nosso país, provavelmente devido ao rastreamento ser realizado principalmente em áreas urbanas e haver áreas menos favorecidas onde os programas de rastreamento não são efetivos. É bem sabido que a mortalidade pelo câncer raramente é devida ao tumor primário, mas à disseminação metastática das células tumorais em órgãos distantes. A via linfática é considerada a preferencial para disseminação metastática nos tumores ginecológicos. E o estágio clínico e os linfonodos regionais são considerados os fatores prognósticos mais potentes no carcinoma de colo útero. A compreensão da linfangiogênese pode ser considerada uma importante chave na elucidação dos mecanismos usados pelas células tumorais na sua disseminação. Os objetivos do presente estudo são avaliar as características clínico-patológicas do câncer do colo do útero e sua associação com o comprometimento linfonodal e o desfecho; avaliar a linfangiogênese intratumoral pela análise quantitativa da microdensidade vascular linfática (MDVL), usando o método imunoistoquímico para marcação dos vasos linfáticos e três métodos morfométricos para a quantificação; determinar a associação entre a MDVL, características clínico-patológicas de apresentação, comprometimento linfonodal, desfecho e a expressão de podoplanina em células neoplásicas e a expressão da podoplanina em células fibroblásticas do estroma intratumoral. Os estudos sobre a MLVD em câncer de colo de útero são raros e controversos. Nossos resultados demonstraram que a MLVD foi mais acentuada nos tumores de menor tamanho (<2 cm), nos estádios iniciais (IB1), com menos infiltrações, sem comprometimento vascular e sem comprometimento linfonodal, provavelmente porque a indução da linfangiogênese pode ser um evento inicial na progressão do câncer, quando ainda nem todos os vasos neoformados estão funcionantes ou patentes. Isto explicaria a elevada MLVD nos tumores iniciais quando os linfonodos estavam frequentemente negativos. Observou-se que não não houve associação significativa entre expressão de podoplanina em células neoplásicas e comprometimento vascular, comprometimento dos linfonodos ou desfecho. A expressão de podoplanina em fibroblastos do estroma intratumoral no câncer precoce de colo de útero está associada a melhor prognóstico. Até o presente, acreditase que este seja o primeiro estudo a investigar o papel da expressão da podoplanina no estroma intratumoral de carcinoma precoce do colo do útero, relacionando-a com MLVD, comprometimento dos linfonodos e o desfecho / Cervix carcinoma incidence remains still high in our country, probably as the screening occurrence is carried out mainly in the urban areas and there are less favored areas where the screening programs are not effective. It is well known that the cancer mortality is rarely caused by the primary tumor, but it is caused by the metastatic spread of tumor cells in distant organs. The lymphatic route is considered the choice for the metastatic dissemination in the gynecological tumors. And the clinical stage and the regional lymphonodes are considered the most powerful prognostic factors in the uterine cervix cancer. The understanding of the lymphangiogenesis can be considered an important key for the elucidation of the mechanisms used in the tumor cells dissemination. The current study objectives are to evaluate the clinic-pathological characteristics of the uterine cervix carcinoma and its association with the lymphnodal involvement and outcome; to evaluate the intratumoral lymphangiogenesis by the quantitative analysis of the lymphatic vessel micro density (LVMD), using the immunoistochemical method for marking the lymphatic vessels and three morphometric methods for the quantification. To determine the association between the LVMD, the clinicpathological characteristics, the lymphonodal involvement and outcome and the podoplanin expression in neoplasic cells and in fibroblastic cells of the intratumoral stroma. Studies about the LVDM in uterine cervical cancer are rare and controversial. Our results demonstrated that the LVDM was more remarkable in the smaller tumors(<2cm), in the initial stages (IB1), with less infiltrations, with no vascular involvement and no lymphnodal involvement. Probably because the induction of lymphangiogenesis may be an early event in cancer progression, while still not all the newly formed vessels are functioning or patent. This would explain the high LVMD in the initial tumors while the lymphonodes were frequently negative. It was noted that there were no significant association between podoplanin expression in neoplasic cells and vessel involvement, lymphonodes involvement or outcome. Podoplanin expression in fibroblasts of the intratumoral stroma in early cervix carcinoma was associated to better prognosis. To date, it is believed that this is the first study to investigate the role of podoplanin expression in intratumoral stroma of cervix carcinoma, relating it to LVMD, lymph node involvement and outcome
28

Pathogenesis of calcific aortic valve disease

Näpänkangas, J. (Juha) 08 October 2019 (has links)
Abstract Calcific aortic valve disease (CAVD) represents a disease spectrum, ranging from mild aortic valve sclerosis to severe obstructive aortic stenosis (AS), associated with a high risk of myocardial infarction and cardiovascular death. It is a common disease in the Western countries, and with their aging populations, its prevalence is likely to increase. Today, CAVD is recognized as an actively regulated disease. Mechanical stress and endothelial injury are the initiating factors, followed by lipid accumulation and oxidation, leading to inflammation, fibrosis and calcification. Ultimately, the progressive calcification hinders the normal valvular function and obstructs the flow of blood through the valve. The only effective treatment for symptomatic AS is aortic valve replacement. The trials with pharmacological treatments, mainly with anti-atherosclerotic drugs, have not been successful in slowing the progression of the disease. This study was aimed to identify differentially expressed transcripts, and molecular markers taking part in the pathophysiology behind CAVD. In particular, factors related to the renin-angiotensin system, and the apelin – APJ pathway, were investigated during the development of CAVD. In addition, the expressions of granzymes and perforin, as well as podoplanin, were studied in different stages of CAVD. It was demonstrated that these molecules are expressed in aortic valves and dysregulated in AS. These results can help to clarify the mechanisms driving CAVD, thus being potential targets for pharmacological therapy. Furthermore, the studied molecules may reflect the stage and possible subgroups of CAVD. / Tiivistelmä Aorttaläpän ahtauma edustaa tautijatkumoa, joka alkaa lievästä aorttaläpän paksuuntumisesta eli aorttaskleroosista ja jatkuu vaikeaan aorttaläpän kalkkeutuneeseen ahtaumaan eli aorttastenoosiin, johon liittyy korkea sydäninfarktin ja sydän- ja verisuonitatutiperäisen kuoleman riski. Aorttaläpän ahtauma on yleinen tauti länsimaissa, ja väestön ikääntyessä sen esiintyvyys on luultavimmin lisääntymässä. Nykyään aorttaläpän ahtauman tiedetään olevan aktiivisesti säädelty tauti. Mekaaninen rasitus ja endoteelivaurio käynnistävät tautiprosessin, läppäkudokseen kertyy lipidejä ja ne hapettuvat, mikä johtaa tulehdukseen, sidekudoksen lisääntymiseen ja kalkkeutumiseen. Lopulta etenevä kalkkeutuminen heikentää läpän normaalia toimintaa ja estää veren normaalia virtausta sydämestä aorttaan. Ainoa tehokas hoito oireiseen aorttastenoosiin on aorttaläpän korvausleikkaus. Lääkehoitoina on kokeiltu erityisesti ateroskleroosin hoitoon käytettäviä lääkkeitä, mutta niillä ei ole onnistuttu estämään taudin etenemistä. Tässä väitöskirjatyössä tutkittiin molekyylejä ja biokemiallisia reittejä, jotka liittyvät reniini-angiotensiinijärjestelmään ja apeliini-APJ-reittiin. Lisäksi tutkittiin grantsyymien ja perforiinin sekä podoplaniinin ilmentymistä aorttaläpän ahtauman eri kehitysvaiheissa. Tulosten perusteella näitä tekijöitä ilmennetään aorttaläpässä ja niiden määrä on muuttunut kalkkeutuneessa läpässä. Tulokset auttavat osaltaan ymmärtämään aorttaläpän ahtaumaan ja kalkkeutumiseen johtavia mekanismeja, joita voidaan hyödyntää uusia lääkehoidon kohteita suunniteltaessa. Tutkitut molekulaariset tekijät voivat kuvastaa aortan ahtaumataudin vaiheita ja mahdollisia alaryhmiä.
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Kidney Hyaluronan : Regulatory Aspects During Different States of Body Hydration, Nephrogenesis &amp; Diabetes

Rügheimer, Louise January 2008 (has links)
The kidney regulates the excretion of water and electrolytes, which maintains homeostasis and enables control of arterial blood pressure. Hyaluronan, a large negatively charged interstitial glucosaminoglycan, is heterogeneously distributed within the kidney, primarily found in the medulla. Medullary hyaluronan content changes depending on the state of body hydration and plays a part in fluid regulation through its water binding and viscoelastic properties. The aim of this thesis was to provide new insight into the regulation of intrarenal hyaluronan during different states of body hydration, during completion of kidney development, and during diabetes mellitus. Dehydration reduces medullary interstitial hyaluronan in parallel with reduced hyaluronan synthase 2 gene expression and increased urinary hyaluronidase activity. Acute hydration results in an increase in medullary hyaluronan, an increase that requires nitric oxide and prostaglandins. Urinary hyaluronidase activity decreases during hydration. The elevation of hyaluronan is important for reducing water permeability of the interstitium i.e. favoring diuresis. Changes in hyaluronan concentration constitute a morphoregulatory pathway that plays a key role in nephrogenesis. The reduction in neonatal hyaluronan depended on an angiotensin II mediated process that does not appear dependent on lymph vessel formation. If angiotensin II is blocked with an ACE inhibitor, hyaluronan accumulates, which results in structural and functional abnormalities in the kidney. Renomedullary hyaluronan is elevated during uncontrolled diabetes, which coincides with induction of hyaluronan synthase 2 mRNA, hyperglycemia, glucosuria, proteinuria and overt diuresis. The levels of hyaluronan are probably at a terminus ad quem as no further response was seen during hydration. The higher interstitial expression of hyaluronan during diabetes may be involved in the progression of diabetic nephropathy. This thesis in physiology provides new mechanistic insights into the regulation of renal hyaluronan during various aspects of fluid handling.
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Imunoexpress?o do EGFR e da podoplanina em cistos radiculares e dent?geros

Maia, Viviane Alves de Oliveira 13 February 2014 (has links)
Made available in DSpace on 2014-12-17T15:32:23Z (GMT). No. of bitstreams: 1 VivianeAOM_DISSERT.pdf: 3188421 bytes, checksum: 338aa2ec46045198a33e6eea1db0d483 (MD5) Previous issue date: 2014-02-13 / The radicular cysts (RCs) and dentigerous (DCs), despite having different etiologies, form a pathological cavity lined by epithelium, which grows due to the buildup of fluid inside, as the surrounding bone is reabsorbed and the epithelium will being induced to proliferate. The epithelial proliferation, which has been identified as one of the key processes in the growth of odontogenic cystic lesions, is influenced by growth factors such as EGFR (epidermal growth receptor factor) and podoplanin (PDPN), many of which may have its production stimulated mainly during inflammatory processes. The objective of this research was to evaluate and compare the immunohistochemical expression of EGFR and PDPN in 30 cases of RCs and 30 cases of DCs, semiquantitatively, in light microscopy, associating it with the degree of inflammation, cellular localization of immunostaining and with the immunostained epithelial layers. Data were statistically analyzed by Chi-square test and Fisher exact test, considering a significance level of 5 %. The results showed high immunoreactivity of both proteins in the lesions studied, only statistically significant difference was observed in immunostaining of PDPN (p=0.033), which proved higher in RCs. The other analyzed parameters showed no relevant significant differences. We conclude that, as EGFR and PDPN showed high immunoreactivity in cystic lesions analyzed, these proteins participate the pathogenesis of these lesions through the epithelial stimulation process, despite having different etiologies. Furthermore, it can infer that the higher immunostaining of PDNP in RCs that DCs showed no distinction indicator between the two lesions, regarding their etiologies, once this protein also showed a considerable expression in DCs, independent of the intensity of the inflammatory infiltrate / Os cistos radiculares (CRs) e dent?geros (CDs), apesar de possu?rem etiologias diferentes, formam uma cavidade patol?gica revestida por epit?lio, a qual cresce em fun??o do ac?mulo de l?quido em seu interior, ? medida que o osso ao redor ? reabsorvido e o epit?lio vai sendo induzido a proliferar. A prolifera??o epitelial, que tem sido apontada como um dos processos determinantes no crescimento das les?es c?sticas odontog?nicas, ? influenciada por fatores de crescimento como o EGFR (receptor do fator de crescimento epid?rmico) e a podoplanina (PDPN), muitos dos quais podem ter sua produ??o estimulada principalmente durante processos inflamat?rios. O objetivo desta pesquisa foi avaliar e comparar a express?o imunoistoqu?mica do EGFR e da PDPN em 30 casos de CRs e 30 casos de CDs, de forma semiquantitativa, em microscopia de luz, associando-a com o grau de inflama??o, localiza??o celular da imunocolora??o e com as camadas epiteliais imunomarcadas. Os dados foram avaliados estatisticamente por meio de testes do Qui-quadrado e Exato de Fisher, considerando-se um n?vel de signific?ncia de 5%. Os resultados mostraram que houve elevada imunorreatividade das duas prote?nas nas les?es estudadas, sendo observada apenas diferen?a estat?stica significativa na imunoexpress?o da PDPN (p=0,033), que se mostrou mais elevada nos CRs. Os demais par?metros analisados n?o demonstraram diferen?as significativas relevantes. Conclui-se que, como o EGFR e a PDPN apresentaram elevada imunoexpress?o nas les?es c?sticas analisadas, essas prote?nas participam da patog?nese dessas les?es atrav?s da estimula??o epitelial, apesar de apresentarem etiologias diferentes. Al?m disso, pode-se inferir que a maior imunomarca??o da PDPN em CRs do que em CDs n?o se mostrou indicador de distin??o entre as duas les?es, com rela??o ?s suas etiologias, uma vez que nestes ?ltimos essa prote?na tamb?m apresentou express?o consider?vel, independente da intensidade do infiltrado inflamat?rio

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