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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.
1

Efeito do BAY 41-2272 em linfócitos T humanos. / Effect of BAY 41-2272 in human T lymphocytes.

Carvalho, Marina Uchôa Wall Barbosa de 23 April 2018 (has links)
No presente trabalho avaliamos o potencial do BAY 41-2272 e sua via, como uma ferramenta para modulação da função dos linfócitos. Para isso, realizamos tratamentos farmacológicos com BAY 41-2272, avaliando a produção de citocinas e observamos que este fármaco, como ativador direto, não induz produção de IFN, IL-4 e IL-10 nos linfócitos. No entanto, o prétratamento por 24 horas com BAY 41-2272, com posterior ativação com PMA, mostrou que esta droga tem efeito inibitório na produção das citocinas. Em vista disto, avaliamos se este fármaco seria capaz de ativar estas células através da expressão de CD69. Vimos que por si só esta droga não foi capaz de aumentar a expressão de CD69, no entanto o pré-tratamento com BAY 41-2272 inibiu a ativação dos linfócitos T CD4. Assim, avaliamos se o fármaco seria capaz de inibir a expressão de fatores de transcrição FOXP3, RORT, Tbet e GATA3. Vimos que o BAY 41-2272 não induziu expressão desses fatores de transcrição e o pré-tratamento com este fármaco não alterou a expressão de FOXP3, RORT e GATA3, mas inibiu a expressão de Tbet quando comparado ao estimulado com PMA e Ionomicina sem o prétratamento. Observamos também que o pré-tratamento com BAY 41-2272 inibiu a linfoproliferação. Estes resultados sugerem que o BAY 41-2272 e sua via, têm um perfil inibitório sobre os linfócitos T CD4, e potencialmente podem ser utilizados como imunomodulador em pacientes com comprometimento do sistema imunológico e síndromes linfoproliferativas. / In this work, we evaluated the potential of BAY 41-2272 and its pathway as a tool for modulating lymphocyte function. For this, we performed pharmacological treatments with BAY 41-2272, evaluating the production of cytokines and observed that this drug, as a direct activator, does not induce production of IFN, IL-4 e IL-10. However, pre-treatment for 24 hours with BAY 41-2272 and subsequente activation with PMA showed that this drug has an inhibitory effect on cytokine production. Thus, we evaluated if this drug would be able to activate these cells through the CD69 expression. We saw that alone, BAY 41-2272 was not able to increase CD69 expression, however, pre-treatment inhibited activation of CD4 T lymphocytes. Then, we evaluated if this chemical compound would be able to inhibite the expression of transcription factors FOXP3, RORT, Tbet and GATA3. We have seen that BAY 41-2272 did not induce expression of these transcription factors and pretreatment with this drug did not alter expression of FOXP3, RORT and GATA3, but inhibited Tbet expression. We also observed that pre-treatment with BAY 41-2272 inhibited lymphoproliferation. These results suggest that BAY 41-2272 and its pathway have an inhibitory profile on CD4 T lymphocytes and can potentially be used as an immunomodulator in patients with impaired imune system and lymphoproliferative syndromes.
2

Efeito do BAY 41-2272, estimulador de guanilato ciclase solúvel, em neutrófilos humanos / Efeito do BAY 41-2272, estimulador de guanilato ciclase solúvel, em neutrófilos humanos

Rosa, Paola Vendramini Ferreira 28 November 2018 (has links)
Os neutrófilos estão entre as principais células da imunidade inata e são as primeiras células a migrarem para o sítio de infecção. O BAY 41-2272, estimulador de guanilato ciclase solúvel, é capaz de ativar fagócitos mononucleares e em neutrófilos diminuir migração in vivo e in vitro. O presente trabalho teve como objetivo avaliar o potencial do BAY 41-2272, e sua via, como uma ferramenta farmacológica para modulação da função dos neutrófilos. Para isso foi realizado o tratamento in vitro dos PMNs com o BAY 41-2272. A viabilidade celular, quimiotaxia e funções efetoras como burst oxidativo e produção de citocinas foram avaliadas, observando-se que o BAY 41-2272, como ativador direto, não altera estas funções. No entanto, o pré-tratamento com BAY 41-2272 nas doses de 3 M e 30M por uma hora, com subsequente ativação com PMA, mostrou perfil inibitório na quimiotaxia, produção da citocina IL-8 e no burst oxidativo . Foram avaliados também a expressão de moléculas como CD15, CD31, CD35, CD49d, CD63, CD66b, CD162 e a produção de GMPc. As moléculas de superfícies não mostraram alterações após tratamento direto com BAY 41-2272. A produção de GMPc foi induzida na dose de 30 M de BAY 41-2272 e pelo SNAP (doador de NO). Esses dados sugerem um potencial inibitório do BAY 41-2272 sobre a ação dos neutrófilos, e uma possível alternativa a ser explorada em seus aspectos translacionais na busca por novas terapias destinadas ao controle de doenças ligadas a inflamações crônicas e doenças auto-imunes. / Neutrophils are the major cells of innate immunity and are the first cells to migrate to the site of infection. BAY 41-2272, a soluble guanylate cyclase stimulator, is capable of activating mononuclear phagocytes and in neutrophils decreasing migration in vivo and in vitro. The present work aimed to evaluate the potential of BAY 41-2272, and its pathway, as a pharmacological tool for modulating neutrophil function. For this, the in vitro treatment of PMNs with BAY 41-2272 was performed. Cell viability, chemotaxis and effector functions such as oxidative burst and cytokine production were evaluated, observing that BAY 41-2272, as a direct activator, does not alter these functions. However, pretreatment with BAY 41-2272 at the doses of 3 M and 30 M for one hour, with subsequent activation with PMA, showed an inhibitory profile in chemotaxis, IL-8 cytokine production and in the \"oxidative burst\". We also evaluated the expression of molecules such as CD15, CD31, CD35, CD49d, CD63, CD66b, CD162 and cGMP production. Surface molecules did not show changes after direct treatment with BAY 41-2272. The cGMP production was induced at the dose of 30 M BAY 41-2272 and for SNAP (NO donor). These data suggest an inhibitory potential of BAY 41-2272 on the action of neutrophils, and a possible alternative to be explored in its translational aspects in the search for new therapies aimed at the control of diseases linked to chronic inflammation and autoimmune diseases.
3

Nitric oxide-cGMP signal transduction in the injury, matrix expansion and progression of anti-thy1-induced renal disease of the rat

Wang, Yingrui 14 April 2005 (has links)
Hintergrund. Die gegensätzlichen Wirkungen des L-Arginin-NO-Stoffwechsels bei Nierenerkrankungen wurden nachgewiesen. Die vorliegende Studie untersucht die Haupt-Endstrecke dieses Stoffwechselweges, die NO-cGMP-Signaltransduktion, sowie die Wirkung des spezifischen sGC-Stimulators Bay 41-2272 auf Schädigungs-, Matrixexpansions- und Progressionsphase der Anti-Thy1-induzierten Nierenerkrankungen im Rattenmodell. Methoden. Die anti-Thy1-Antikörperinjektion in zwei Nieren- oder uninephrektomierten Ratten induzierte eine Sequenz der Schädigungs-, Matrixexpansions- und Progressionsphase. Die Effekte der Behandlung mit Bay 41-2272 (10 mg/kg Körpergewicht/Tag) wurden durch die Messungen von systolischem Blutdruck, Proteinurie, Nierenfunktion, glomerulärer und interstitieller Matrixakkumulation, TGF-beta1-, Fibronectin- und PAI-1-Expression, Makrophageninfiltration, alpha1sGC, beta1sGC, sowie basaler und NO-stimulierter renaler cGMP-Produktion ermittelt. Im chronischen Anti-Thy1 Modell wurden die Effekte von Bay 41-2272 mit dem reinen Vasodilator Hydralazin (15 mg/kg Körpergewicht/Tag) verglichen. Ergebnisse. Im Vergleich zu den Kontrollen sind die sGC mRNA Expression und Aktivität signifikant im Matrixexpansionsprotokoll erhört, während sie im Schädigungsprotokoll komplett vermindert sind; im Progressionsprotokoll ist die sGC-cGMP-Kaskade im Tubulointerstitium hochreguliert, während die Aktivität im Glomeruli erniedrigt ist. Im Gegensatz zur Hydralazin-therapie erhörte die Bay 41-2272-Behandlung die glomeruläre und die tubulointerstitielle NO-cGMP-Signaltransduktion. Dies führte zu deutlich verringerten Makrophageninfiltration, Matrixakkumulation sowie einer verbesserten Nierenfunktion. Schlussfolgerung. Die Expression und Aktivität der sGC sind auf Transkriptionsebene im Verlauf der Nierenfibrose hochreguliert und korrelieren eng mit den pathologischen Veränderungen in den einzelnen Krankheitsphasen. Pharmakologische sGC-Stimulation reduzierte die TGF-beta-Überexpression sowie die Matrixakkumulation und verlangsamte den fortschreitenden Verlauf zur tubulointerstitiellen Fibrose und eingeschränkten Nierenfunktion über teilweise blutdruckunabhängige Mechanismen, obwohl die Mesangialzelllyse infolge der verminderten sGC-Expression unbeeinflusst blieb. Die Ergebnisse zeigen, dass die NO-cGMP-Signaltransduktion ein wichtiger antifibrotischer Mechanismus bei Nierenfibrose ist. / Background Controversial effects of L-arginine-NO pathway have been shown on renal disease. The present study analyzes the main downstream of L-arginine-NO pathway, the NO-cGMP signaling in and the effect of the specific sGC stimulator Bay 41-2272 on the injury, matrix expansion and progression phases in the rat model of anti-thy1-induced renal disease. Methods The injection of anti-thy1 antibody into rats with two kidneys or nephrectomized rats caused a sequence of the injury, matrix expansion and progression phases. The effects of Bay 41-2272 (10 mg/kg body weight/d) treatment on systolic blood pressure, proteinuria, kidney function, glomerular and tubulointerstitial matrix protein accumulation, expression of TGF- beta1, fibronectin and PAI-1, macrophage infiltration, alpha1sGC and beta1sGC mRNA expression and basal and NO-stimulated renal cGMP production were determined. In the chronic anti-thy1 model, the effect of Bay 41-2272 was compared side-by-side to the sole vasodilator hydralazine (15 mg/kg body weight/d). Results Compared to controls, sGC mRNA expression and activity were markedly increased in the matrix expansion protocol, while they were almost completely disrupted in the injury protocol; in the progression protocol, sGC-cGMP cascade was up-regulated in the tubulointerstitium, while its activity was decreased in glomeruli. In contrast to hydralazine therapy, Bay 41-2272 treatment enhanced both glomerular and tubulointerstitial NO-cGMP signaling significantly, resulting in markedly reduced macrophage infiltration, matrix expression and accumulation as well as improved kidney function. Conclusion The expression and activity of sGC are highly regulated at the transcriptional level during the course of renal fibrosis, and correlate closely with the pathological changes from the injury over the matrix expansion toward the final progression phase. Further pharmacologic sGC stimulation reduced TGF-beta overexpression and extracellular matrix accumulation and limited the progressive course of this model towards tubulointerstitial fibrosis and impaired renal function at least in part in a blood pressure-independent manner, although it demonstrated no effects on mesangial cell lysis due to lack of the receptor sGC. The results suggest that NO-cGMP signaling represents an important anti-fibrotic pathway in renal fibrosis.
4

Prenatal modulation of the developing lung in congenital diaphragmatic hernia: functional, morphological, and biological consequences for the neonatal lung

Vuckovic, Aline 11 April 2016 (has links)
INTRODUCTION. Congenital diaphragmatic hernia (CDH) combines a congenital malformation of the diaphragm with lung hypoplasia, leading to severe respiratory distress and intractable pulmonary hypertension of the newborn. Despite advances in prenatal diagnosis and neonatal intensive care, CDH is associated with high mortality and devastating morbidities. In the absence of curative treatment, numerous prenatal therapies have been used experimentally with varying success. So far, only fetal tracheal occlusion has been tested in clinical trials, but the consequences for the human lung are poorly known. AIMS. To further characterize the rabbit model of CDH, which was subsequently used to assess the effects of prenatal therapies on airway and pulmonary vascular development, including tracheal occlusion, and two novel approaches, perfluorooctylbromide and an activator of soluble guanylate cyclase (BAY 41–2272), which were given through tracheal instillation.METHODS. After a diaphragmatic incision during the pseudoglandular stage, fetal rabbits were randomized against placebo/sham operation during the saccular stage for tracheal occlusion, perfluorocarbon or BAY 41–2272. At term operated fetuses and controls were subject to evaluation of lung mechanics and/or hemodynamics as well as postmortem lung analyses. Human fetal and neonatal lung tissue, including controls and CDH with tracheal occlusion or expectant management, was analyzed histologically and biochemically.RESULTS. The rabbit model of CDH was characterized by reduced lung volumes and impaired compliance, disorders of elastin deposition within alveolar walls, and downregulation of elastogenesis-related genes. Moreover, this model reproduced features of pulmonary hypertension, including high right ventricular pressure and level of N-terminal-pro-B type natriuretic peptide, remodeling of pulmonary arterioles, decreased alveolar capillary density, and downregulation of vasodilation-related genes. In the rabbit model, lung distension caused by tracheal occlusion improved alveolar formation and elastogenesis, yet without correction of lung mechanical parameters. Tracheal occlusion increased also the expression of other extracellular matrix components, which reflected myofibroblast activity, and reduced the transcription of surfactant-associated proteins. Human neonatal lungs exposed to fetal tracheal occlusion displayed alveolar deposits of collagen and myofibroblasts. In human CDH as well as in the rabbit model of CDH, tracheal occlusion enhanced the pulmonary expression of transforming growth factor-β (TGFβ) and Rho kinase−associated proteins to the detriment of activation of SMAD2/3, which is normally detected in human lungs with advancing gestation. As an alternative to tracheal occlusion, pulmonary distension by perfluorocarbon in the fetal rabbit model of CDH improved lung mechanics and alveolar elastogenesis without transcriptional changes in extracellular matrix, surfactant protein genes or TGFβ. Finally, intratracheal instillation of BAY 41–2272 in the rabbit fetuses with CDH improved hemodynamics, reduced medial hypertrophy of pulmonary arterioles, and increased capillary bed formation by stimulating endothelial cell proliferation.CONCLUSIONS. In the fetal rabbit model of CDH, poor lung function after tracheal occlusion is compatible with activation of TGFβ and imbalance in extracellular matrix and epithelial homeostasis. In human CDH newborns treated by fetal tracheal occlusion, changes in the pulmonary interstitium and impaired TGFβ signaling raise the question of disturbances of postnatal lung development induced by tracheal occlusion. As potential alternatives to tracheal occlusion, prenatal perfluorocarbon improves lung hypoplasia, whereas prenatal BAY 41–2272 attenuates pulmonary hypertension. / Doctorat en Sciences médicales (Médecine) / info:eu-repo/semantics/nonPublished

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