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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.
11

Avaliação dos mecanismos indutores da inflamação pulmonar decorrente da isquemia e reperfusão intestinal em camundongos geneticamente selecionados. / Evaluation of the mechanisms underlying the lung inflammation following intestinal ischemia / reperfusion (I/R) in genetically selected mice.

Victoni, Tatiana 25 June 2008 (has links)
Neste estudo caracterizamos a inflamação pulmonar aguda decorrente da I/R intestinal em camundongos geneticamente selecionados para baixa (AIRmin) ou alta (AIRmax) reatividade inflamatória aguda os quais foram obtidos por Seleção Genética Bidirecional. Paralelamente, camundongos da linhagem Balb/c foram utilizados, como referência dos parâmetros investigados. A isquemia intestinal foi induzida pela obstrução da artéria mesentérica superior (AMS) por 45 min seguida de sua desobstrução. Após 4 h de reperfusão intestinal a inflamação pulmonar foi avaliada por meio da atividade pulmonar de mieloperoxidase (MPO), número de leucócitos (no sangue, na medula óssea e no baço), permeabilidade vascular, dosagem de citocinas (IL-1<font face=\"symbol\">b, IL-10, IL-6 e TNF-<font face=\"symbol\">a) e a produção de nitratos e nitritos em cultura de ex-vivo de tecido pulmonar (explante). A I/R-intestinal induziu aumento da atividade MPO (mieloperoxidase), aumento da permeabilidade vascular pulmonar e neutrofilia nas três linhagens estudadas, com maior intensidade em camundongos AIRmax. A celularidade da medula óssea e baço não foi afetada pela I/R intestinal nas linhagens AIRmin e AIRmax. A I/R intestinal aumentou a atividade de MPO intestinal nas linhagens Balb/c, AIRmin e AIRmax, porém este parâmetro não diferiu dentro das linhagens estudadas. Por outro lado, o intestino não desenvolveu aumento de extravasamento plasmático. O explante pulmonar de animais AIRmax geraram níveis significativamente elevados de nitratos e nitritos após a I/R-intestinal. A quantidade de citocinas produzidas espontaneamente pelo explante pulmonar não diferiu entre as linhagens AIRmin e AIRmax. Todavia, na vigência de estímulo secundário (lipopolisacarídeo), a produção de IL-1<font face=\"symbol\">b e IL-10 foi maior na linhagem AIRmax. A taxa de mortalidade após I/R intestinal não difere entre as linhagens AIRmin e AIRmax, todavia na linhagem AIRmin as mortes ocorrem mais precocemente (4h) após a I/R intestinal, em contraste aquela encontrado nos animais de AIRmax (12h). Concluindo, nossos dados permitem sugerir que os animais geneticamente selecionados reagem diferentemente após a I/R intestinal, de modo que os animais AIRmin mostram uma sensibilidade realçada (nos termos da taxa de mortalidade), e em contrapartida os animais AIRmax um maior reatividade (nos termos da resposta inflamatória para I/R). Contudo, nós sugerimos que as alterações genotípicas devido à seleção podem explicar uma exacerbada resposta inflamatória para I/R em camundongos AIRmax coexistindo com um perfil mais favorável de letalidade visto que o oposto é observado em animais de AIRmin. / The aim of this study was to characterize the acute lung inflammation due to intestinal I/R in mice selected for high (AIRmax) or low (AIRmin) acute inflammatory response by means of bidirectional genetic selection. Balb/c mice were also used as a reference control of the parameters evaluated. Intestinal ischemia was induced by a 45-min clamping of the superior mesenteric artery; the clamping was then released and the lung inflammation was evaluated after a 4-h reperfusion period by measurements of myeloperoxidase (MPO) lung activity, leukocyte number (in blood, bone marrow and spleen), vascular permeability, cytokines (IL-1<font face=\"symbol\">b, IL-10, IL-6 and TNF-<font face=\"symbol\">a) and production of nitrates and nitrites in lung tissue ex vivo cultures (explants). Intestinal I/R induced an increase of the lung acute inflammatory reaction as judged by the increase of MPO activity and of vascular permeability and the influx of neutrophils in every animallineage studied, being the AIRmax mice the most reactive ones. However, the cellularity of the bone marrow and spleen was not affected by intestinal I/R in AIRmax or AIRmin mice. Intestinal I/R caused an increase of MPO activity in the gut of Balb/c, AIRmax and AIRmin mice, with no differences from each other. On the other hand, no intestinal plasma extravasation was noticed. Nitrites and nitrates production was higher in cultures of AIRmax mice lung explants after intestinal I/R. The spontaneous production of cytokines was not different among AIRmax and AIRmin lung explants, being significantly increased in AIRmax samples upon bacteriallipopolysaccharide (LPS) stimulation(IL-1<font face=\"symbol\">b e IL-10). The profile of mortality among AIRmax and AIRmin was not altered by intestinal I/R. However, the mortality rate of injured AIRmin mice was found as early as 4 h after intestinal I/R, in contrast with that found in AIRmax animals (12 h after). In conclusion, our data suggest that genetically selected AIRmax and AIRmin mice react differentially to intestinal I/R, so that AIRmin mice show enhanced sensitivity (in terms of mortality rate), and their AIRmax counterparts show enhanced responsiveness (in terms of inflammatory response to I/R). Overall, we suggest that the genotypic changes due to selection may explain why an exacerbated inflammatory response to I/R in AIRmax mice coexists with a more favorable profile oflethality, whereas the opposite is seen in AIRmin animals.
12

Immunomodulation induite par la pré-sensibilisation per os à Norovirus dans un modèle murin de pneumonie aiguë à Pseudomonas aeruginosa / MNV infection in P. aeruginosa mouse model of acute lung injury

Thépaut, Marion 25 September 2015 (has links)
Le norovirus murin (MNV) est un agent pathogène de la souris récemment découvert et représente le contaminant le plus courant dans les animaleries de Recherche. Néanmoins, les effets de l'infection au MNV sur la recherche biomédicale ne sont pas encore clairs. Nous avons testé l'hypothèse que l'infection au MNV pourrait modifier la réponse immunitaire chez les souris atteintes d'une infection pulmonaire aiguë. Nous rapportons ici que la co-infection avec MNV augmente la survie des souris ayant une infection pulmonaire aiguë à Pseudomonas aeruginosa et diminue la production in vivo et in vitro de cytokines pro-inflammatoires. Nos résultats suggèrent que l'infection au MNV peut profondément modifier les paramètres étudiés dans les modèles classiques d'infection et mener à de fausses conclusions dans ces modèles expérimentaux. / The murine norovirus (MNV) is a recently discovered mouse pathogen, this virus represents the most common contaminant in laboratory mouse colonies. Nevertheless, the effects of MNV infection on biomedical research are still unclear. We tested the hypothesis that MNV infection could alter immune response in mice with acute lung infection. Here we report that co-infection with MNV increases survival of mice with Pseudomonas aeruginosa acute lung injury and decreases in vivo and in vitro production of pro-inflammatory cytokines. Our results suggest that MNV infection can deeply modify the parameters studied in conventional models of in-fection and lead to false conclusions in experimental models.
13

Participação glutamatérgica nos efeitos induzidos pela anfetamina na resposta inflamatória alérgica pulmonar de camundongos / Glutamatergic involvement in amphetamine-induced effects on pulmonary allergic inflammatory response in mice

Eduardo Kenji Hamasato 06 September 2011 (has links)
O objetivo do presente estudo foi avaliar a participação do sistema glutamatérgico nos efeitos induzidos pela anfetamina em camundongos sensibilizados e desafiados com ovalbumina, através do tratamento prévio com MK-801, um antagonista de receptores glutamatérgicos NMDA. Em relação aos animais tratados apenas com anfetamina, observamos que o tratamento prévio com MK-801: 1) reverteu a diminuição no número de leucócitos totais bem como o número de eosinófilos e neutrófilos no lavado broncoalveolar (LBA); 2) reverteu a diminuição da porcentagem de expressão das moléculas L-selectina e ICAM-1 em granulócitos do LBA; 3) reverteu a diminuição das citocinas IL-10 e IL-13 no sobrenadante do LBA; 4) reverteu a diminuição na contração da traquéia; 5) reverteu a desgranulação de mastócitos pulmonares; 6) não alterou a produção de IgE total e IgE-OVA; 7) não reduziu os níveis de corticosterona plasmáticos. Tomados em seu conjunto, quer nos parecer que os efeitos induzidos pela anfetamina implicam na ativação do sistema glutamatérgico via receptores NMDA. Possivelmente, as diferenças dos efeitos do MK-801, da anfetamina ou a combinação de fármacos se devam a uma ativação (modulação) diferenciada sobre o eixo hipotálamo pituitária adrenal (HPA) e/ou sistema nervoso autônomo simpático (SNAS) o que poderia explicar os efeitos opostos observados na resposta inflamatória alérgica pulmonar de camundongos. / The aim of this study was to evaluate the involvement of the glutamatergic system in the effects induced by amphetamine in mice OVA-sensitized and challenged by the pretreatment with MK-801, an NMDA glutamate receptor antagonist. In relation to animals treated only with amphetamine we found that pretreatment with MK-801: 1) reverted the decrease in the total leukocytes and in the total number of eosinophils and neutrophils within the bronchoalveolar lavage fluid (BAL) 2) reverted the decrease in the percentage of expression of adhesion molecules L-selectin and ICAM-1 in BAL granulocytes, 3) reverted the decrease in IL-10 and IL-13 in BAL supernatant and 4) reverted the decrease in methacoline-induced tracheal contraction; 5) reverted the degranulation of mast cells in the lungs; 6) did not alter the production of total IgE and IgE-OVA, 7) did not decrease the plasma levels of corticosterone. Taken together, it seems feasible to suggest that the effects induced by amphetamine requires the participation of the glutamatergic system via NMDA receptors. Possibly, differences in MK-801, amphetamine or MK-801 + amphetamine effects on hypothalamic pituitary adrenal axis (HPA) and/or sympathetic autonomic nervous system (SNAS) might explain the opposite effects now observed for these drugs given alone or in combination in the pulmonary allergic inflammatory response in mice.
14

Role of 18F FDG PET/CT as a novel non-invasive biomarker of inflammation in chronic obstructive pulmonary disease

Choudhury, Gourab January 2018 (has links)
A characteristic feature of Chronic Obstructive Pulmonary Disease (COPD) is an abnormal inflammatory response in the lungs to inhaled particles or gases. The ability to assess and monitor this response in the lungs of COPD patients is important for understanding the pathogenic mechanisms, but also provides a measure of the activity of the disease. Disease activity is more likely to relate to lung inflammation rather than the degree of airflow limitation as measured by the FEV1. Preliminary studies have shown the 18F fluorodeoxyglucose positron emission tomography (18F FDG-PET) signal, as a measure of lung inflammation, is quantifiable in the lungs and is increased in COPD patients compared to controls. However, the methodology requires standardisation and any further enhancement of the methodology would improve its application to assess inflammation in the lungs. I investigated various methods of assessing FDG uptake in the lungs and assessed the reproducibility of these methods, and particularly evaluated whether the data was reproducible or not in the COPD patients (smokers and ex-smokers). This data was then compared with a group of healthy controls to assess the role of dynamic 18F FDG-PET scanning as a surrogate marker of lung inflammation. My data showed a good reproducibility of all methods of assessing FDG lung uptake. However, using conventional Patlak analysis, the uptake was not statistically different between COPD and the control group. Encouraging results in favour of COPD patients were nonetheless shown using compartmental methods of assessing the FDG lung uptake, suggesting the need to correct for the effect of air and blood (tissue fraction effect) when assessing this in a highly vascular organ like the lungs. A prospective study analysis involving a bigger cohort of COPD patients would be desirable to investigate this further.
15

Mathematical Models of the Inflammatory Response in the Lungs

Minucci, Sarah B 01 January 2017 (has links)
Inflammation in the lungs can occur for many reasons, from bacterial infections to stretch by mechanical ventilation. In this work we compare and contrast various mathematical models for lung injuries in the categories of acute infection, latent versus active infection, and particulate inhalation. We focus on systems of ordinary differential equations (ODEs), agent-based models (ABMs), and Boolean networks. Each type of model provides different insight into the immune response to damage in the lungs. This knowledge includes a better understanding of the complex dynamics of immune cells, proteins, and cytokines, recommendations for treatment with antibiotics, and a foundation for more well-informed experiments and clinical trials. In each chapter, we provide an in-depth analysis of one model and summaries of several others. In this way we gain a better understanding of the important aspects of modeling the immune response to lung injury and identify possible points for future research.
16

Etude des mécanismes moléculaires responsables d'un état inflammatoire intrinsèque dans la mucoviscidose.

Verhaeghe, Catherine 21 June 2007 (has links)
Summary: While multiple organs are affected in cystic fibrosis (CF) patients, chronic lung disease is the most severe clinical manifestation caused by chronic bacterial infection and concomitant airway inflammation. The sequence of events at the onset of pulmonary infection and inflammation is controversial and not fully characterized. The aim of this work was to highlight an early inflammatory state in CF airways before any infection and to investigate the molecular mechanisms underlying this intrinsic inflammation. We showed increased levels of pro-inflammatory proteins in the lungs of a CF fetus compared to the lungs of two normal fetuses. Using different CF cell models, we confirmed the over-production of numerous pro-inflammatory molecules. We then demonstrated that the transcription of these inflammatory genes is NF-kB and AP-1-dependent and that these transcription factors are activated through IKK and ERK kinase activation. We also identified that the IL-1b and bFGF inhibition, two pro-inflammatory proteins over-expressed in our CF models, decreased the expression of several pro-inflammatory genes. Among the molecules over-secreted by CF epithelial cells, chemokines such as IL-8, Gro-a, Gro-b, Gro-g and ENA-78 or growth factors such as VEGF and bFGF are know to be pro-angiogenic factors. We further demonstrated that conditioned media from CF epithelial cells were able to induce proliferation, migration and sprouting of cultured primary endothelial cells. Our data demonstrated that the absence of CFTR (CF transmembrane conductance regulator) at the plasma membrane leads to an intrinsic AP-1 and NF-kB activation. These activations lead to a pro-inflammatory state sustained through autocrine factor secretion and also through the angiogenic process induced by CF epithelial cells.
17

Rôle des cathepsines à cystéine dans la régulation du peptide antimicrobien LL-37 lors de pathologies inflammatoire chroniques pulmonaires / Role of cysteine cathepsis in the regulation of the antimicrobial peptide LL-37 during chronic lung inflammatory diseases

Andrault, Pierre-Marie 17 December 2015 (has links)
Lors de pathologies pulmonaires inflammatoires chroniques comme la mucoviscidose ou la BPCO, le déséquilibre de la balance protéases/antiprotéases aboutit à la dégradation du tissu pulmonaire et à l’inactivation des défenses antimicrobiennes. Les cathepsines à cystéine participent à l’inactivation protéolytique de peptides et protéines antimicrobiens (PAMs) pulmonaires comme le SLPI, la lactoferrine, et les β-défensines HBD-2 et -3 lors de l’emphysème ou de la mucoviscidose. Lors de cette thèse, nous avons étudié la capacité des cathepsines à cystéine B, K, L et S à hydrolyser le peptide LL-37, qui est un PAM important dans l’immunité innée pulmonaire. Seules les cathepsines K et S clivent le LL-37 et inactivent efficacement son activité antimicrobienne. A l’inverse, le LL-37 est un inhibiteur compétitif de la cathepsine L. D’autre part, l’expression pulmonaire de la cathepsine S est fortement augmentée chez les individus fumeurs atteints ou non de BPCO. La fumée de cigarette qui est une source importante de stress oxydatif induit une augmentation significative de l'expression et l'activité de la cathepsine S. Malgré un environnement oxydatif non favorable à l'activité des cathepsines, la cathepsine S parvient à hydrolyser le peptide LL-37 et pourrait ainsi augmenter le risque d’exacerbation lors de la BPCO. / During chronic inflammatory lung diseases like cystic fibrosis or COPD, proteases/antiproteases imbalance leads to pulmonary tissue degradation and compromise antimicrobial barrier. Cysteine cathepsins are involved in the proteolytic inactivation of several lung antimicrobial peptides (AMPs) such as SLPI, lactoferrin and β- defensins -2 and -3 during emphysema or cystic fibrosis. During this thesis, we studied the ability of cathepsins B, K, L and S to degrade LL-37, which is an important AMP in lung immunity. Only cathepsins K and S degrade readily LL-37 and inactivate its antimicrobial property. Conversely, LL-37 is a competitive inhibitor of cathepsin L. Beside, lung expression of human cathepsin S is significantly increased in smokers with or without COPD compared to non-smokers. Cigarette smoke that is a major source of oxidative stress significantly increases the expression and activity of cathepsin S. Despite an unfavorable oxidative environment, cathepsin S retains its proteolytic activity toward LL-37 and thus could participate to COPD exacerbation.
18

Avaliação dos mecanismos indutores da inflamação pulmonar decorrente da isquemia e reperfusão intestinal em camundongos geneticamente selecionados. / Evaluation of the mechanisms underlying the lung inflammation following intestinal ischemia / reperfusion (I/R) in genetically selected mice.

Tatiana Victoni 25 June 2008 (has links)
Neste estudo caracterizamos a inflamação pulmonar aguda decorrente da I/R intestinal em camundongos geneticamente selecionados para baixa (AIRmin) ou alta (AIRmax) reatividade inflamatória aguda os quais foram obtidos por Seleção Genética Bidirecional. Paralelamente, camundongos da linhagem Balb/c foram utilizados, como referência dos parâmetros investigados. A isquemia intestinal foi induzida pela obstrução da artéria mesentérica superior (AMS) por 45 min seguida de sua desobstrução. Após 4 h de reperfusão intestinal a inflamação pulmonar foi avaliada por meio da atividade pulmonar de mieloperoxidase (MPO), número de leucócitos (no sangue, na medula óssea e no baço), permeabilidade vascular, dosagem de citocinas (IL-1<font face=\"symbol\">b, IL-10, IL-6 e TNF-<font face=\"symbol\">a) e a produção de nitratos e nitritos em cultura de ex-vivo de tecido pulmonar (explante). A I/R-intestinal induziu aumento da atividade MPO (mieloperoxidase), aumento da permeabilidade vascular pulmonar e neutrofilia nas três linhagens estudadas, com maior intensidade em camundongos AIRmax. A celularidade da medula óssea e baço não foi afetada pela I/R intestinal nas linhagens AIRmin e AIRmax. A I/R intestinal aumentou a atividade de MPO intestinal nas linhagens Balb/c, AIRmin e AIRmax, porém este parâmetro não diferiu dentro das linhagens estudadas. Por outro lado, o intestino não desenvolveu aumento de extravasamento plasmático. O explante pulmonar de animais AIRmax geraram níveis significativamente elevados de nitratos e nitritos após a I/R-intestinal. A quantidade de citocinas produzidas espontaneamente pelo explante pulmonar não diferiu entre as linhagens AIRmin e AIRmax. Todavia, na vigência de estímulo secundário (lipopolisacarídeo), a produção de IL-1<font face=\"symbol\">b e IL-10 foi maior na linhagem AIRmax. A taxa de mortalidade após I/R intestinal não difere entre as linhagens AIRmin e AIRmax, todavia na linhagem AIRmin as mortes ocorrem mais precocemente (4h) após a I/R intestinal, em contraste aquela encontrado nos animais de AIRmax (12h). Concluindo, nossos dados permitem sugerir que os animais geneticamente selecionados reagem diferentemente após a I/R intestinal, de modo que os animais AIRmin mostram uma sensibilidade realçada (nos termos da taxa de mortalidade), e em contrapartida os animais AIRmax um maior reatividade (nos termos da resposta inflamatória para I/R). Contudo, nós sugerimos que as alterações genotípicas devido à seleção podem explicar uma exacerbada resposta inflamatória para I/R em camundongos AIRmax coexistindo com um perfil mais favorável de letalidade visto que o oposto é observado em animais de AIRmin. / The aim of this study was to characterize the acute lung inflammation due to intestinal I/R in mice selected for high (AIRmax) or low (AIRmin) acute inflammatory response by means of bidirectional genetic selection. Balb/c mice were also used as a reference control of the parameters evaluated. Intestinal ischemia was induced by a 45-min clamping of the superior mesenteric artery; the clamping was then released and the lung inflammation was evaluated after a 4-h reperfusion period by measurements of myeloperoxidase (MPO) lung activity, leukocyte number (in blood, bone marrow and spleen), vascular permeability, cytokines (IL-1<font face=\"symbol\">b, IL-10, IL-6 and TNF-<font face=\"symbol\">a) and production of nitrates and nitrites in lung tissue ex vivo cultures (explants). Intestinal I/R induced an increase of the lung acute inflammatory reaction as judged by the increase of MPO activity and of vascular permeability and the influx of neutrophils in every animallineage studied, being the AIRmax mice the most reactive ones. However, the cellularity of the bone marrow and spleen was not affected by intestinal I/R in AIRmax or AIRmin mice. Intestinal I/R caused an increase of MPO activity in the gut of Balb/c, AIRmax and AIRmin mice, with no differences from each other. On the other hand, no intestinal plasma extravasation was noticed. Nitrites and nitrates production was higher in cultures of AIRmax mice lung explants after intestinal I/R. The spontaneous production of cytokines was not different among AIRmax and AIRmin lung explants, being significantly increased in AIRmax samples upon bacteriallipopolysaccharide (LPS) stimulation(IL-1<font face=\"symbol\">b e IL-10). The profile of mortality among AIRmax and AIRmin was not altered by intestinal I/R. However, the mortality rate of injured AIRmin mice was found as early as 4 h after intestinal I/R, in contrast with that found in AIRmax animals (12 h after). In conclusion, our data suggest that genetically selected AIRmax and AIRmin mice react differentially to intestinal I/R, so that AIRmin mice show enhanced sensitivity (in terms of mortality rate), and their AIRmax counterparts show enhanced responsiveness (in terms of inflammatory response to I/R). Overall, we suggest that the genotypic changes due to selection may explain why an exacerbated inflammatory response to I/R in AIRmax mice coexists with a more favorable profile oflethality, whereas the opposite is seen in AIRmin animals.
19

Estudo da resposta inflamatoria pulmonar alergica em ratos expostos a enterotoxina estafilococica do tipo A (SEA) / Study of pulmonary allergic inflammation in rat after airway exposition to staphylococcal enterotoxin type A (SEA)

Mariano, Nadia Sabrina 14 August 2018 (has links)
Orientadores: Edson Antunes, Ivani Aparecida de Souza / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-14T02:35:58Z (GMT). No. of bitstreams: 1 Mariano_NadiaSabrina_M.pdf: 621386 bytes, checksum: b01cd4d186fa15a5e8ea3c7657df604a (MD5) Previous issue date: 2009 / Resumo: O Staphylococcus aureus é um tipo de bactéria gram-positiva que produz e secreta uma série de enterotoxinas com propriedade imunomoduladoras. Entretanto, pouco é conhecido sobre os mecanismos envolvidos na exacerbação do influxo celular observado em indivíduos asmáticos expostos a enterotoxinas estafilocócicas. O objetivo desse trabalho é investigar os efeitos da exposição das vias aéreas à enterotoxina estafilocócica do tipo A (SEA) sobre o recrutamento de leucócitos para o pulmão de ratos sensibilizados e desafiados com ovalbumina (OVA). Em nossos protocolos experimentais, ratos foram expostos à SEA 4 h antes ou 4 h após o desafio antigênico com OVA. O lavado broncoalveolar (LBA), a medula óssea e o tecido pulmonar foram obtidos 24 h após o desafio com OVA. A pré-exposição à SEA aumentou significativamente o número de eosinófilos no LBA e no tecido pulmonar de ratos desafiados com OVA, enquanto que o número de neutrófilos e células mononucleares não foi significativamente alterado. Na medula óssea, a pré-exposição à SEA isoladamente aumentou significativamente o número de eosinófilos, sendo esse aumento potencializado em ratos desafiados com OVA. Por outro lado, a pós-exposição à SEA não afetou o número de eosinófilos, neutrófilos ou células mononucleares observadas no LBA. A pré-exposição ao LPS em animais desafiados com OVA aumentou somente o número de neutrófilos no LBA. No LBA de ratos pré-expostos à SEA e desafiados com OVA, notamos uma elevação significativa nos níveis de TNF-? e eotaxina, mas não de IL-10. Os níveis de eotaxina presentes em sobrenadante de cultura de macrófagos alveolares tratados com SEA in vitro aumentaram cerca de 3 vezes em relação a macrófagos não estimulados com SEA. Concluímos que a pré-exposição (mas não a pós-exposição) das vias aéreas de ratos à SEA aumenta seletivamente o número de eosinófilos presente no LBA, tecido pulmonar e medula óssea de ratos desafiados com OVA por mecanismos que envolvem o aumento na síntese de TNF-? e eotaxina / Abstract: Gram-positive Staphylococcus aureus releases classical enterotoxins which aggravates allergic airway diseases. However, little is known about the mechanisms underlying the cell influx exacerbation in asthmatic individuals under exposure to Staphylococcal enterotoxins. We therefore aimed to investigate the effects of airways exposure to Staphylococcal enterotoxin A (SEA) to pulmonary leukocyte recruitment in rats sensitized and challenged with ovalbumin (OVA). Rats were exposed to SEA at 4 h prior to OVA challenge or at 4 h post-OVA challenge. Bronchoalveolar lavage (BAL) fluid, bone marrow and lung tissue were obtained at 24 h after OVA challenge. Preexposure to SEA markedly enhanced the eosinophil counts in both BAL fluid and pulmonary tissue in OVA-challenged rats, whereas neutrophil and mononuclear cell counts remained unchanged. In bone marrow, pre-exposure to SEA alone significantly increased the number of eosinophils, and that was further increased in OVA-challenged rats. Exposure to SEA post-OVA challenge did not affect the number of eosinophils, neutrophils and mononuclear cells in BAL fluid. Pre-exposure to the endotoxin lipopolyssacharide (LPS) in OVA-challenged animals rather enhanced the neutrophil number in BAL fluid. In rats pre-exposed to SEA and OVA-challenged, a marked elevation in the levels of TNF-? and eotaxin (but not of IL-10) in BAL fluid was observed. The eotaxin levels increased by about of 3-fold in alveolar macrophages treated with SEA in vitro. In conclusion, airways pre-exposure to SEA (but not the postexposition) causes a selective increase in eosinophil number in BAL fluid, lung tissue and bone marrow of OVA-challenged rats by mechanisms involving enhancement of TNF-? and eotaxin synthesis / Mestrado / Farmacologia / Mestre em Farmacologia
20

Expression And Function Of Human IkappaBzeta In Lung Inflammation

Sundaram, Kruthika 08 October 2015 (has links)
No description available.

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