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Modulação da expressão de galectina-3 frente às pressões seletivas de pH e oxigenação: um mecanismo para a heterogeneidade intratumoral? / Modulation of galectin-3 expression regarding to pH and oxygenation selective pressures: a mechanism for intratumoral heterogeneity?Ana Carolina Ferreira Cardoso 31 October 2014 (has links)
A heterogeneidade intratumoral é um fenômeno extremamente importante para entender a progressão tumoral e a resposta à intervenção terapêutica. A galectina-3 pertence à família das lectinas, possuem a função de reconhecimento e ligação à ?-galactosídeos ramificados de glicolipídeos e glicoproteínas, e está envolvida em processos fisiológicos e patológicos como o câncer. Nesse trabalho, a heterogeneidade intratumoral em relação à expressão de galectina-3 foi observada em amostras de diferentes lesões melanocíticas de pacientes. Além disso, o inóculo de células de melanoma murino negativas para galectina-3 em animais gal3-/- gerou tumores constituídos por uma fração de células tumorais que passaram a expressar de novo galectina-3, sugerindo que pressões do microambiente tumoral modulam a expressão dessa lectina em melanomas. A acidose extracelular atuou como regulador negativo de galectina-3 in vitro, diminuindo a expressão dessa lectina tanto em células de melanoma murino e humano quanto em melanócito murino. Entretanto, a hipóxia, seja pela exposição aguda ou intermitente, não alterou a expressão in vitro de galectina-3 em células de melanoma humano. Por fim, tumores originados pelo inóculo de células tumorais positivas e negativas para galectina-3 (mimetizando tumores heterogêneos) obtiveram a maior taxa de crescimento tumoral comparados aos tumores constituídos por uma única população de células, seja positiva ou negativa para galectina-3. Portanto, foram apresentadas evidências de que a heterogeneidade intratumoral em relação à galectina-3 parece estar envolvida com o sucesso evolutivo do melanoma e que a acidose é indicada como uma das pressões microambientais que contribuem para o estabelecimento e manutenção da fração de células tumorais negativas para galectina-3 dentro da massa tumoral / The intratumoral heterogeneity observed in human tumors is extremely important to understand tumor progression and its therapeutic response. Galectin-3 belongs to animal lectin family and it is a ?-galactosidase binding protein which is involved in physiological and pathological processes, including cancer. In this work, an intratumor heterogeneous galectin-3 expression was observed in tissue sessions containing different human melanocytic lesions. Moreover, negative galectin-3 murine cells injected into gal3-/- mice were able to generate tumors composed of a positive galectin-3 cell fraction, suggesting that selective forces in tumor microenvironment modulate galectin-3 expression in melanoma. Extracellular acidosis acts as a negative regulator to galectin-3 in vitro, decreasing its expression in murine and human melanoma cells and even in murine melanocytes. However, intermittent or acute hypoxia exposure did not alter galectin-3 expression in human melanoma cells in vitro. In addition, tumors originated from a mixture of positive and negative galectin-3 cells (mimicking heterogeneous tumors) showed higher growth rate compared to those derived from only galectin-3 positive or negative cells. Therefore, we showed evidences that galectin-3 intratumoral heterogeneity seems to be involved with the evolutionary success of melanoma and that acidosis may be the microenvironmental pressure responsible for the establishment and maintenance of galectin-3 negative cell fraction into the tumor bulk
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Cystinosis : new findings involving inflammation in the kidney pathogenesis and preclinical studies for autologous hematopoietic stem cell gene therapy / La cystinose : nouvelles découvertes impliquant l'inflammation dans la pathogénèse rénale et études précliniques pour la transplantation autologue de cellules souches hématopoïétiques corrigées génétiquementLobry, Tatiana 30 January 2019 (has links)
La cystinose est une maladie lysosomale héréditaire due à une mutation du gène CTNS codant pour un transporteur de cystine, cystinosin, et est caractérisée par l’accumulation de cystine dans les organes causant leur dégénération.Si le rein est le premier organe affecté par la maladie, sa pathogénèse n’est pas encore totalement comprise. La recherche de nouveaux partenaires de la cystinosine a révélé une interaction avec un membre de la famille des galactines, galectine-3 (Gal3). L’étude de cette interaction a mis en évidence un nouveau rôle de la cystinosine dans l’inflammation chronique impliquée dans la pathogénèse rénale de la cystinose. Dans les reins du modèle murin de la cystinose (Ctns-/-), l’expression de Gal3 est augmentée et de nombreux infiltrats de cellules inflammatoires sont observés. De plus, l’expression de la cytokine pro-inflammatoire Monocyte Chemoattractant Protein-1 (MCP1) est augmentée dans le sérum des souris Ctns-/-.Au contraire, peu d’infiltrat et un taux normal de MCP1 sont observés dans les souris Ctns-/-Gal3-/-, ainsi qu’une meilleure structure et fonction rénale.Ce travail pourrait permettre la découverte de nouvelles cibles thérapeutiques pour la cystinose.Des études antérieures ont montré que la transplantation de Cellules Souches Hématopoïétiques (CSH) saines peut efficacement traiter la cystinose dans les souris Ctns-/-. Toutefois, dû aux risques liés à une transplantation allogénique, une transplantation autologue de CSH génétiquement modifiées ex vivo pour exprimer une copie fonctionnelle du gène CTNS a été développée.Nous résumons ici les études pharmacologiques et toxicologiques ainsi que le développement du protocole de transduction des cellules humaines qui seront inclus dans une application intitulée« Investigational New Drug » qui sera soumise à la FDA afin de débuter un essai clinique de phase I/II. / Cystinosis is an inherited lysosomal storage disorder caused by mutations in the gene CTNS encoding the cystine transporter cystinosin, and is characterized by accumulation of cystine in the tissues leading to multiorgan degeneration.The kidney is the first organ impacted by cystinosis but the pathogenesis is still not fully understood. The study of new partners of cystinosin revealed an interaction with galectin-3, a member of the galectin’s family. The investigation of this interaction unraveled a new role for cystinosin in chronic inflammation associated with kidney pathology in cystinosis. Indeed, the cystinosis mouse model, Ctns-/ mice, had increased expression of Gal3 and abundant pro-inflammatory infiltrates in their kidney, as well as increased expression of Monocyte Chemoattractant Protein-1 (MCP1), a proinflammatory cytokine, in their serum.In contrast, few infiltrates and normal MCP1 levels were observed in the Ctns-/- Gal3-/- mice, which also demonstrated better kidney structure and function.This study may lead to the discovery of new drug targets for cystinosis treatment.Previous studies showed that wild-type Hematopoietic Stem Cells (HSCs) transplantation had the potential to rescue cystinosis in Ctns-/- mice.However, due to the risks associated with allogeneic transplant, an autologous transplantation of HSCs genetically modified ex vivo to express a functional CTNS gene has been developed in the laboratory. In this work, we summarized the pharmacology and toxicology studies and manufacturing development that will be included in an Investigational New Drug application to be submitted to the FDA to start a phase I/II clinical trial for cystinosis.
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"Expressão imunoistoquímica da proteína galectina-3 em carcinoma adenóide cístico e adenocarcinoma polimorfo de baixo grau de malignidade de glândulas salivares" / Galectin-3 immunoprofile in adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma of salivary glandsFerrazzo, Kivia Linhares 04 July 2006 (has links)
O carcinoma adenóide cístico e o adenocarcinoma polimorfo de baixo grau de malignidade são neoplasias malignas das glândulas salivares que apresentam semelhança nos padrões histológicos, porém com comportamento clínico, tratamento e prognóstico completamente diferentes. A galectina-3 é uma proteína multifuncional da família das lectinas que está envolvida em vários fenômenos biológicos como crescimento celular, adesão celular, diferenciação celular e apoptose. Além disso, tem sido estudada como um marcador de invasão tumoral e metástase. O objetivo deste trabalho foi estudar qualitativamente a expressão imunoistoquímica da galectina-3 em 14 casos de carcinoma adenóide cístico (2 do subtipo tubular, 4 do subtipo sólido e 8 do subtipo cribriforme) e em 12 casos de adenocarcinoma polimorfo de baixo grau de malignidade com padrões histológicos variados, incluindo os padrões lobular, tubular e cribriforme. Espécimes de glândula salivar normal foram também incluídos na amostra. Nas glândulas salivares normais houve forte marcação da galectina-3 no núcleo e no citoplasma das células luminais dos ductos. Nos carcinomas adenóides císticos houve uma maior marcação da galectina-3 no subtipo tubular, localizada apenas nas células luminais das estruturas tubulares. Nos subtipos sólido e cribriforme a marcação foi menor, mas sempre localizada nas células que circundavam espaços luminais. Em todos os casos de carcinomas adenóides císticos estudados a marcação foi predominantemente nuclear. Nos adenocarcinomas polimorfos de baixo grau de malignidade a marcação da galectina-3 foi predominantemente citoplasmática em praticamente todas as células neoplásicas. Diante disso podemos sugerir que, nas neoplasias estudadas, a expressão da galectina-3 parece estar mais relacionada à diferenciação celular do que à progressão tumoral e ao prognóstico. / Adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma are malignant neoplasms of salivary glands which are similar in histologic patterns but very different in clinical behavior, treatment and prognosis. Galectin-3 is a multifunctional protein of a growing family of beta-galactoside-binding animal lectins which is implicated in a variety of biological events such as tumor cell adhesion, proliferation, differentiation and angiogenesis. This protein was found to be implicated in cellular transformation, and a correlation between its expression and cancer progression and metastasis has been described. The aim of this study was to determine the galectin-3 immunoprofile in 14 cases of adenoid cystic carcinoma (2 cases of tubular subtype, 4 cases of solid subtype and 8 cases of cribriform subtype) and in 12 cases of polymorphous low-grade adenocarcinoma with different histologic patterns, included lobular, tubular and cribriform. Moreover, slides of normal salivary glands were included. In normal salivary glands there were strong nuclei and cytoplasmic staining for galectin-3 in ductal luminal cells. Adenoid cystic carcinomas showed specific staining in luminal cells mainly in the nuclei. In the tubular subtype of adenoid cystic carcinoma galectin-3 was strong in the luminal cells of the ductiform structures. The cribriform and solid subtypes showed a few positive cells for galectin-3 only in the luminal cells of small ducts presenting in the cribriform structures and in solid nests respectly. In the cases of polymorphous low-grade adenocarcinoma, independent of the histologic architecture, all tumor cells revealed a positive cytoplasmic reaction with the galectin-3 antibody. Galectin-3 expression seems to be related to cell differentiation more than tumor progression and prognosis in the neoplasms studied.
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La Galectine-3, médiateur des effets de l'aldostérone sur le remodelage cardiovasculaire / Galectin-3 is a Mediator of Aldosterone Effects on Cardiovascular RemodelingCalvier, Laurent 09 November 2012 (has links)
Contexte : l'aldostérone (Aldo) est impliquée dans la rigidité artérielle et l'insuffisance cardiaque (IC), mais les mécanismes sous-jacents restent méconnus. La galectine-3 (Gal-3), une lectine se liant aux bêta-galactoside, joue un rôle important dans la fibrose et l'IC. Dans cette étude, nous avons recherché si la Gal-3 était impliquée dans la fibrose vasculaire induite par l'Aldo. Méthodes et résultats : Des cellules musculaires lisses vasculaires de rat (CMLVs) ont été stimulées avec de l'Aldo en combinaison avec des antagonistes du récepteur minéralocorticoïde (MR) ou des inhibiteurs de la Gal-3. L'Aldo régule l'expression de la Gal-3 via le MR dans les CMLVs. De plus, la surexpression de la Gal-3 augmente spécifiquement la synthèse de collagène de type I. Les inhibiteurs de la Gal-3 ou sa sous-expression (siRNA) bloquent la synthèse de collagène de type I induite par l'Aldo. Des rats ont été traités avec de l'Aldo + sel combiné avec du spironolactone ou de la pectine de citron modifiée (MCP) pendant 3 semaines. Les rats hypertensifs traités à l'Aldo ont présenté une hypertrophie vasculaire, une fibrose et une augmentation de l'expression aortique de Gal-3. Les traitements avec le spironolactone ou le MCP préviennent tous ces effets. Des souris sauvages (WT) et mutées pour la Gal-3 (KO) ont été traitées avec de l'Aldo pendant 6 heures. Le bolus d'Aldo augmente l'expression de la Gal-3 et du collagène de type I dans l'aorte des souris WT alors qu'aucun changement ne se produit dans les souris KO pour la Gal-3. Conclusions : Nos donnés indiquent que la Gal-3 est indispensable à la réponse fibrotique de l'Aldo dans les CMLVs in vitro et in vivo, suggérant un rôle clef pour la Gal-3 dans la fibrose vasculaire / Background. Aldosterone (Aldo) is involved in arterial stiffness and heart failure (HF), but the mechanisms have remained unclear. Galectin-3 (Gal-3), a beta-galactoside-binding lectin, plays an important role in fibrosis and HF. We here investigated whether Gal-3 is involved in Aldo-induced vascular fibrosis. Methods and Results. Rat vascular smooth muscle cells (VSMCs) were stimulated with Aldo combined with mineralocorticoid receptor (MR) antagonists and Gal-3 inhibitors. Aldo upregulated Gal-3 expression via MR in VSMCs. Moreover, Gal-3 over-expression specifically enhanced collagen type I synthesis. Gal-3 inhibitors or Gal-3 silencing (siRNA) blocked Aldo-induced collagen type I synthesis. Rats were treated with Aldo-salt combined with spironolactone or modified citrus pectin (MCP) for 3 weeks. Hypertensive Aldo-treated rats presented vascular hypertrophy, fibrosis and increased aortic Gal-3 expression. Spironolactone or MCP treatment reversed all the above effects. Wild type (WT) and Gal-3 knock-out (KO) mice were treated with Aldo for 6 hours. Aldo bolus increased aortic Gal-3 and collagen type I expression in WT mice whereas no changes occurred in Gal-3 KO mice. Conclusions. Our data indicate that Gal-3 is required for the fibrotic response to Aldo in VSMCs in vitro and in vivo, suggesting a key role for Gal-3 in vascular fibrosis
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"Expressão imunoistoquímica da proteína galectina-3 em carcinoma adenóide cístico e adenocarcinoma polimorfo de baixo grau de malignidade de glândulas salivares" / Galectin-3 immunoprofile in adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma of salivary glandsKivia Linhares Ferrazzo 04 July 2006 (has links)
O carcinoma adenóide cístico e o adenocarcinoma polimorfo de baixo grau de malignidade são neoplasias malignas das glândulas salivares que apresentam semelhança nos padrões histológicos, porém com comportamento clínico, tratamento e prognóstico completamente diferentes. A galectina-3 é uma proteína multifuncional da família das lectinas que está envolvida em vários fenômenos biológicos como crescimento celular, adesão celular, diferenciação celular e apoptose. Além disso, tem sido estudada como um marcador de invasão tumoral e metástase. O objetivo deste trabalho foi estudar qualitativamente a expressão imunoistoquímica da galectina-3 em 14 casos de carcinoma adenóide cístico (2 do subtipo tubular, 4 do subtipo sólido e 8 do subtipo cribriforme) e em 12 casos de adenocarcinoma polimorfo de baixo grau de malignidade com padrões histológicos variados, incluindo os padrões lobular, tubular e cribriforme. Espécimes de glândula salivar normal foram também incluídos na amostra. Nas glândulas salivares normais houve forte marcação da galectina-3 no núcleo e no citoplasma das células luminais dos ductos. Nos carcinomas adenóides císticos houve uma maior marcação da galectina-3 no subtipo tubular, localizada apenas nas células luminais das estruturas tubulares. Nos subtipos sólido e cribriforme a marcação foi menor, mas sempre localizada nas células que circundavam espaços luminais. Em todos os casos de carcinomas adenóides císticos estudados a marcação foi predominantemente nuclear. Nos adenocarcinomas polimorfos de baixo grau de malignidade a marcação da galectina-3 foi predominantemente citoplasmática em praticamente todas as células neoplásicas. Diante disso podemos sugerir que, nas neoplasias estudadas, a expressão da galectina-3 parece estar mais relacionada à diferenciação celular do que à progressão tumoral e ao prognóstico. / Adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma are malignant neoplasms of salivary glands which are similar in histologic patterns but very different in clinical behavior, treatment and prognosis. Galectin-3 is a multifunctional protein of a growing family of beta-galactoside-binding animal lectins which is implicated in a variety of biological events such as tumor cell adhesion, proliferation, differentiation and angiogenesis. This protein was found to be implicated in cellular transformation, and a correlation between its expression and cancer progression and metastasis has been described. The aim of this study was to determine the galectin-3 immunoprofile in 14 cases of adenoid cystic carcinoma (2 cases of tubular subtype, 4 cases of solid subtype and 8 cases of cribriform subtype) and in 12 cases of polymorphous low-grade adenocarcinoma with different histologic patterns, included lobular, tubular and cribriform. Moreover, slides of normal salivary glands were included. In normal salivary glands there were strong nuclei and cytoplasmic staining for galectin-3 in ductal luminal cells. Adenoid cystic carcinomas showed specific staining in luminal cells mainly in the nuclei. In the tubular subtype of adenoid cystic carcinoma galectin-3 was strong in the luminal cells of the ductiform structures. The cribriform and solid subtypes showed a few positive cells for galectin-3 only in the luminal cells of small ducts presenting in the cribriform structures and in solid nests respectly. In the cases of polymorphous low-grade adenocarcinoma, independent of the histologic architecture, all tumor cells revealed a positive cytoplasmic reaction with the galectin-3 antibody. Galectin-3 expression seems to be related to cell differentiation more than tumor progression and prognosis in the neoplasms studied.
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Polymorphisms and Biologic Effects of Acidic Mammalian Chitinase in AsthmaWachtel, Heather 28 September 2009 (has links)
In this study, we hypothesize that human acidic mammalian chitinase (AMCase) binds and is regulated by the epidermal growth factor receptor (EGFR), and that AMCase interacts with Galectin-3 (Gal-3) to mediate anti-apoptotic functions. We further hypothesize that asthma-associated polymorphisms of AMCase alter chitinase activity and modulate anti-apoptotic effects. We investigated the interactions between AMCase, Gal-3 and EGFR by establishing binding and co-expression in vitro; apoptotic effects were evaluated via Annexin V/Propidium Iodide staining. Molecular cloning was performed to generate single nucleotide polymorphisms (SNPs) of AMCase associated with asthma. Our data showed that co-expression of AMCase and EGFR induces chitinase activity; we found that AMCase and Gal-3 bind each other in vitro, and that they co-localize in the cytoplasm of cells. Co-transfection of AMCase and Gal-3 demonstrates greater anti-apoptotic effect than Gal-3 alone, while recombinant Gal-3 induces apoptosis, which is not blocked by incubation with recombinant AMCase. From these data, we conclude that AMCase is regulated by EGFR, and that AMCase and Gal-3 physically interact, however contrary to our hypothesis, the anti-apoptotic effects of AMCase are unlikely to be mediated by Gal-3. Further exploration of this pathway using SNP constructs generated in this study will shed light on the mechanism of AMCase in asthma.
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Avaliação de polimorfismos genéticos como biomarcadores na evolução da cardiomiopatia chagásicaCruz, Gabriela da Silva January 2014 (has links)
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Previous issue date: 2014 / Fundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Salvador, BA, Brasil / O Trypanosoma cruzi é um parasita intracelular e agente causador da doença de Chagas, que afeta milhões de pessoas em todo o mundo. Sabe-se que durante os processos de inflamação, regeneração e fibrose desencadeados pelo T. cruzi no hospedeiro há a participação de diversos mediadores e fatores. O objetivo deste trabalho foi avaliar a associação entre polimorfismos de nucleotídeos únicos com as formas clínicas e o grau de fibrose em pacientes com doença de Chagas. Os polimorfismos foram analisados por PCR em tempo real. Foram incluídos no estudo 55 pacientes com diagnóstico de doença de Chagas e classificados de acordo com a forma clínica da doença, sendo que 17 apresentavam a forma indeterminada, 15 a forma cardíaca sem disfunção ventricular e 23 a forma cardíaca com disfunção ventricular. Os genótipos CA dos polimorfismos do gene LGALS3 (rs4644 e rs4652); AG e GG do SOCS3 (rs4969170); CT e TT do IL-28B (rs12979860 e 8099917, respectivamente); AG, AG, CC, AG e AG do CLDN-1 (rs10212165, rs3909582, rs9865082, rs9880018 e rs9848283, respectivamente); e CC do CCL5 (rs2280789) foram estatisticamente mais frequentes em pacientes com a forma cardíaca do que com a forma indeterminada da doença. Com relação ao grau de fibrose, os genótipos CC dos polimorfismos do gene LGALS3 (rs4644 e rs4652); AA do SOCS3 (rs4969170); CC do rs12979860 e TT do rs8099917 do IL-28B; AA do rs10212165, AA, AG e GG do rs3909582, CC e CT do rs9865082, AG e GG do rs9880018 e AA do rs9848283 do gene CLDN1; e CC do CCL5 (rs2280789) foram estatisticamente mais frequentes em indivíduos com fibrose cardíaca <15% quando comparados com o grupo com fibrose ≥15%. Diante do exposto concluimos que os polimorfismos analisados podem ser úteis como futuros biomarcadores para estadiamento e conduta terapêutica em pacientes com doença de Chagas. / Trypanosoma cruzi is an intracellular parasite and the agent that causes Chagas disease, which affects millions of people worldwide. Several factors and mediators are known to actively participate in the inflammation, fibrosis and tissue regeneration, which is triggered by T. cruzi within the host. The aim of this study was to evaluate the association of single nucleotide polymorphisms with clinical forms and rate of fibrosis in Chagas disease patients. The polymorphisms were analyzed by real-time PCR. The study consisted of 55 Chagas disease patients that were classified according to the clinical form of the disease, including 17 patients presenting the indeterminate form, 15 patients presenting the cardiac form without ventricular dysfunction and 23 patients presenting the cardiac form with ventricular dysfunction. The genotypes of CA of LGALS3 gene polymorphisms (rs4644 and rs4652); AG and GG of SOCS3 (rs4969170); CT and TT of IL-28B (rs12979860 and 8099917, respectively); AG, AG, CC, AG and AG of CLDN-1 (rs10212165, rs3909582, rs9865082, rs9880018 and rs9848283, respectively); and CC of CCL5 (rs2280789) were significantly more frequent in patients presenting the cardiac form compared to patients presenting the indeterminate form. Regarding the degree of fibrosis, the CC genotype of polymorphisms of the genes LGALS3 (rs4644 and rs4652); AA of SOCS3 (rs4969170); CC of rs12979860 and TT of rs8099917 of the IL-28B; AA of rs10212165 and AA, AG and GG of rs3909582, CC and CT of rs9865082, AG and GG of rs9880018 and AA of rs9848283 of the gene CLDN1; and CC of CCL5 (rs2280789) were statistically more frequent in patients presenting <15% cardiac fibrosis when compared to patients presenting fibrosis ≥15%. Taken together, our results suggest that the polymorphisms analyzed may be useful biomarkers for therapeutic management of patients with Chagas disease.
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Estudo da associaÃÃo entre a acromegalia e a presenÃa da mutaÃÃo BRAFV600E e a expressÃo imunohistoquÃmica de IGF-1 e galectina-3 no carcinoma papilÃfero de tireoide. / Study of the association between acromegaly and the presence of BRAFV600E mutation and immunohistochemical expression of IGF-1 and galectin-3 in papillary thyroid carcinoma.Renan MagalhÃes Montenegro 31 August 2012 (has links)
nÃo hà / INTRODUÃÃO: Estudos epidemiolÃgicos sugerem que o carcinoma de tireoide seja a neoplasia maligna mais frequente nos pacientes acromegÃlicos. Atà este momento nÃo hà relatos de estudos avaliando marcadores moleculares do carcinoma papilÃfero de tireoide (CPT) nessa populaÃÃo. OBJETIVOS: Avaliar a associaÃÃo entre acromegalia, presenÃa da mutaÃÃo BRAFV600E, marcadores imunohistoquÃmicos (galectina-3 e IGF-1) e caracterÃsticas clÃnico-patolÃgicas em pacientes acromegÃlicos com CPT. MATERIAL E MÃTODOS: Trata-se de um estudo transversal realizado no perÃodo de janeiro/09 a dezembro/2011, onde 11 pacientes acromegÃlicos com CPT, provenientes de 5 centros brasileiros de referÃncia no tratamento da acromegalia foram comparados com 45 pacientes com CPT sem acromegalia. Foram estudadas variÃveis clÃnicas e histopatolÃgicas do CPT. Utilizou-se cortes histolÃgicos de CPT emblocados em parafina para o estudo da mutaÃÃo BRAFV600E e para a anÃlise imunohistoquÃmica dos marcadores IGF-1 e galectina-3. Na anÃlise utilizou-se os testes t de student e do qui-quadrado (software SPSS, versÃo 13.0 para Windows) (p<0,05). RESULTADOS: A idade mÃdia dos pacientes acromegÃlicos com CPT foi de 61,5  6,02 anos, sendo 72,7% do sexo feminino. O tempo mÃdio de diagnÃstico da acromegalia foi de 7,7  3,90 anos, sendo o intervalo entre o diagnÃstico da acromegalia e do CPT, em mÃdia, 3,4  2,71 anos. Os nÃveis sÃricos de IGF-1 dos acromegÃlicos ao diagnÃstico do CPT foi de 417,0 ng/mL. NÃo houve diferenÃa quanto ao estadiamento TNM (Tumor, Nodule, Metastasis) e Ãndice prognÃstico AMES (Ages, Metastasis, Extent, Size) entre os grupos. Houve maior prevalÃncia da mutaÃÃo BRAFV600E (90,9% vs 55,6%; p=0,039) e de forte imunoexpressÃo para IGF-1 (88,9% vs 38,1%; p= 0,017) nos acromegÃlicos. NÃo houve diferenÃa na expressÃo de galectina-3 entre os grupos. CONCLUSÃO: Neste trabalho, pela primeira vez se mostrou uma alta prevalÃncia da mutaÃÃo BRAFV600E em CPT de acromegÃlicos, muito superior à descrita na populaÃÃo com CPT neste e em estudos anteriores (cerca de 40%). Contudo essa mutaÃÃo nÃo se mostrou associada a um fenÃtipo mais agressivo do tumor, o que diverge dos achados em populaÃÃo nÃo acromegÃlica com CPT. Conclui-se que a acromegalia à possivelmente associada à mutaÃÃo BRAFV600E em pacientes acromegÃlicos com CPT. Novos estudos serÃo necessÃrios para definir os mecanismos responsÃveis por tal associaÃÃo. / INTRODUCTION: Epidemiological studies suggest that thyroid carcinoma is the most common malignant neoplasm in acromegalic patients. At this moment there are no reports of studies evaluating molecular markers of papillary thyroid carcinoma (PTC) in this population. OBJECTIVES: The present work aimed to evaluate the association between acromegaly, expression of the mutation BRAFV600E, immunohistochemical markers (galectin-3 and IGF-1), and clinical-pathological characteristics in acromegalic patients with PTC. MATERIALS AND METHODS: This is a cross-sectional study conducted from January/09 to December/2011, where 11 acromegalic patients with CPT, from 5 Brazilian centers of reference in the treatment of acromegaly were compared with 45 patients with acromegaly without PTC. We evaluated clinical and histopathological variables of PTC. We used histological PTC embedded in paraffin for mutation study BRAFV600E and immunohistochemical analysis of markers IGF-1 and galectin-3. In the analysis we used the Student t test and chi-square test (SPSS software, version 13.0 for Windows) (p <0.05). RESULTS: The average age of acromegalic patients with PTC was 61.5  6.02 years and 72.7% were female. The average time of diagnosis of acromegaly was 7.7  3.90 years, and the interval between diagnosis of acromegaly and PTC was an average 3.4  2.71 years. The serum levels of IGF-1 in the diagnosis of acromegaly PTC was 417.0 ng / mL. There was no difference in the TNM (Tumor, Nodule, Metastasis) and AMES prognostic index (Ages, Metastasis, Extent, Size) between groups. There was a higher prevalence of the BRAFV600E mutation (90.9% vs 55.6%, p = 0.039) and stronger immunohistochemical expression for IGF-1 (88.9% vs 38.1%, p = 0.017) in acromegaly. There was no difference in the expression of galectin-3 between the groups. CONCLUSION: This work for the first time showed a high prevalence of mutations in BRAFV600E in PTC of acromegalic patients superior to those described in the population with PTC in this and previous studies (approximately 40%). However, this mutation was not associated with a more aggressive tumor phenotype, which differs from the findings in acromegalic population without PTC. We conclude that acromegaly is possibly associated to a mutation BRAFV600E in acromegalic patients with CPT. Further studies are needed to define the mechanisms responsible for this association.
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Unrecognized myocardial infarction and cardiac biochemical markers in patients with stable coronary artery diseaseNordenskjöld, Anna January 2016 (has links)
Aim: The overarching aim of the thesis was to explore the occurrence and clinical importance of two manifestations of myocardial injury; unrecognized myocardial injury (UMI) and altered levels of cardiac biochemical markers in patients with stable coronary artery disease (CAD). Methods: A prospective multicenter cohort study investigated the prevalence, localization, size, and prognostic implication of UMI in 235 patients with stable CAD. Late gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR) imaging and coronary angiography were used. The relationship between UMI and severe CAD and cardiac biochemical markers was explored. In a substudy the short- and longterm individual variation in cardiac troponins I and T (cTnI, cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were investigated. Results: The prevalence of UMI was 25%. Subjects with severe CAD were significantly more likely to exhibit UMI than subjects without CAD. There was a strong association between stenosis ≥70% and presence of UMI in the myocardial segments downstream. The presence of UMI was associated with a significant threefold risk of adverse events during follow up. After adjustments UMI was associated with a nonsignificant numerically doubled risk. The levels of cTnI, NT-proBNP, and Galacin-3 were associated with the presence of UMI in univariate analyses. The association between levels of cTnI and presence of UMI remained significant after adjustment. The individual variation in cTnI, cTnT, and NT-proBNP in subjects with stable CAD appeared similar to the biological variation in healthy individuals. Conclusions: UMI is common and is associated with significant CAD, levels of biochemical markers, and an increased risk for adverse events. A change of >50% is required for a reliable short-term change in cardiac troponins, and a rise of >76% or a fall of >43% is required to detect a long-term reliable change in NT-proBNP.
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The adult neural stem cell niche in ischaemic strokeYoung, Christopher Cheng January 2011 (has links)
Ischaemic stroke is a major cause of mortality and chronic disability for which there is no effective treatment. The subventricular zone (SVZ) is an adult neurogenic niche which mediates limited endogenous repair following stroke. To harness this phenomenon for therapy, it is important to understand how the SVZ niche is altered in stroke, and the processes that recruit neural precursors to the site of injury, which becomes a de facto neurogenic niche. Galectin-3 (Gal-3) is a β-galactoside binding protein involved in cellular adhesion, inflammation and tumour metastasis. Gal-3 is specifically expressed in the SVZ and maintains neuroblast migration to the olfactory bulb, although its role in post-stroke neurogenesis is not well-understood. Therefore, this project aimed to (1) characterise the cytoarchitecture of the SVZ in response to stroke, and (2) examine the role of Gal-3 in stroke outcome and tissue remodelling, and test the hypothesis that Gal-3 is required for neuroblast ectopic migration into the ischaemic striatum. Using the intraluminal filament model of middle cerebral artery occlusion (MCAO) in mice, and whole mounts of the lateral ventricular wall, significant SVZ reactive astrocytosis and increased vascular branching were observed, thereby disrupting the neuroblast migratory scaffold. Stroke increased SVZ cell proliferation without increase in cell death. Post-stroke ependymal cells were enlarged and non-proliferative, and assumed a reactive astroglial phenotype, expressing de novo high levels of glial fibrillary acidic protein. This was associated with focal planar cell polarity misalignment, and turbulent and decreased rate of cerebrospinal fluid flow. These findings demonstrate significant changes in multiple SVZ cell types which are positioned to influence post-stroke neurogenesis and regulation of the neural stem cell niche Gal-3 was up-regulated in the ischaemic brain and ipsilateral SVZ. To elucidate the role of Gal-3 after stroke, MCAO was performed in wildtype and Gal-3 null (Gal-3<sup>-/-</sup>) mice, and parameters of stroke outcome and post-stroke neurogenesis compared. The deletion of Gal-3 did not affect infarct volumes or neurological outcomes, although neuroblast migration into the ischaemic striatum was increased in Gal-3<sup>-/-</sup> brains. Gal-3<sup>-/-</sup> mice failed to mount an angiogenic response in the ischaemic striatum, and this was associated with lower levels of vascular endothelial growth factor (VEGF) and increased anti-angiogenic protein levels. Loss of Gal-3 further disrupted the pro-proliferative neural-vascular interaction at the basement membrane. The current data indicate that Gal-3 is a pleiotropic molecule which has distinct roles in both the SVZ and the post-stroke striatum as niches of adult neurogenesis.
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