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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

Generation of mature type II alveolar epithelial cells from human pluripotent stem cells

Jacob, Anjali 01 November 2017 (has links)
Tissues arising late in evolutionary time, such as lung alveoli that are unique to air breathing organisms, have been challenging to generate in vitro from pluripotent stem cells (PSCs), in part because there are limited lower organism model systems available to provide the necessary developmental roadmaps to guide in vitro differentiation. Furthermore, pulmonary alveolar epithelial type II cell (AEC2) dysfunction has been implicated as a primary cause of pathogenesis in many poorly understood lung diseases that lack effective therapies, including interstitial lung disease (ILD) and emphysema. Here we report the successful directed differentiation in vitro of human PSCs into AEC2s, the facultative progenitors of lung alveoli. Using gene editing to engineer multicolored fluorescent reporter PSC lines (NKX2-1GFP;SFTPCtdTomato), we track and purify human SFTPC+ alveolar progenitors as they emerge from NKX2-1+ endodermal developmental precursors in response to stimulation of Wnt and FGF signaling. Purified PSC-derived SFTPC+ cells are able to form monolayered epithelial spheres (“alveolospheres”) in 3D cultures without the need for mesenchymal co-culture support, exhibit extensive self-renewal capacity, and display additional canonical AEC2 functional capacities, including innate immune responsiveness, the production of lamellar bodies able to package surfactant, and the ability to undergo squamous cell differentiation while upregulating type 1 alveolar cell markers. Guided by time-series global transcriptomic profiling we find that AEC2 maturation involves downregulation of Wnt signaling activity, and the highest differentially expressed transcripts in the resulting SFTPC+ cells encode genes associated with lamellar body and surfactant biogenesis. Finally, we apply this novel model system to generate patient-specific AEC2s from induced PSCs (iPSCs) carrying homozygous surfactant mutations (SFTPB121ins2), and we employ footprint-free CRISPR-based gene editing to observe that correction of this genetic lesion restores surfactant processing in the cells responsible for their disease. Thus we provide an approach for disease modeling and future functional regeneration of a cell type unique to air-breathing organisms.
22

Avaliação quantitativa automática de volumes e densidades pulmonares em TCAR de pacientes com esclerose sistêmica antes e após transplante de medula óssea / Automatic quantification of pulmonary volumes and densities in HRCT of patients with systemic sclerosis before and after bone marrow transplantation

Almeida, Fabrício Arantes de 08 February 2019 (has links)
O objetivo deste estudo foi avaliar as medidas de volume e densidade pulmonar em exames de tomografia computadorizada de alta resolução (TCAR) de tórax de pacientes com esclerose sistêmica (ES), antes e após o transplante de medula óssea (TMO). As medidas foram comparadas com a avaliação funcional e resposta ao tratamento. Este foi um estudo retrospectivo observacional. A avaliação clínica e tomográfica foi realizada antes, após 6 e 18 meses do TMO, dos pacientes com ES que realizaram o procedimento entre 2011 e 2017. A análise quantitativa da TCAR foi feita utilizando programa totalmente automatizado (Yacta), capaz de obter o volume pulmonar, a densidade pulmonar média e os percentis de atenuação (P10, P40, P50, P80 e P90). Os dados clínicos, incluindo o resultado das espirometrias, foram obtidos dos prontuários eletrônicos dos pacientes. A capacidade vital forçada (CVF) aos 18 meses foi utilizada para classificar os pacientes em grupo \"melhor resposta\" (aumento >= 10% dos valores da CVF) ou \"resposta estável\" (redução, estabilidade ou aumento < 10% na CVF). Nenhum paciente apresentou redução da CVF > 10% pós-TMO. Foram incluídos 33 pacientes, com alteração tomográfica ou da função pulmonar antes da realização do TMO. O grupo \"melhor resposta\" foi composto por 15 pacientes (45,4%, 4 homens, idade média de 32,1 anos), enquanto o grupo \"resposta estável\" por 18 pacientes (54,6%, 4 homens, idade média de 37,5 anos). A análise quantitativa das TCAR não demonstrou diferença significativa entre os grupos na fase pré-TMO. No grupo \"melhor resposta\" houve redução significativa da densidade pulmonar média e dos valores dos percentis de densidade após o TMO, destacando-se os percentis 80 e 90. No grupo \"resposta estável\" não houve alteração significativa pós-TMO nos valores de volumes e densidades pulmonares. Concluímos que a análise quantitativa automática da TCAR de pacientes com ES foi capaz de identificar redução significativa da densidadepulmonar nos pacientes com melhora significativa da função pulmonar. Inferimos que, além dos volumes e densidades médias, podem ser utilizados também os percentis de densidade como parâmetro no acompanhamento da doença intersticial. Esta ferramenta pode representar um biomarcador na avaliação de tratamento da doença intersticial pulmonar na ES, complementando as provas de função pulmonar. / The purpose of this study was to evaluate pulmonary volume and density measurements in high resolution computed tomography (HRCT) scans of patients with systemic sclerosis (SSc) before and after bone marrow transplantation (BMT). Measurements were compared with functional assessment and response to treatment. This was a retrospective observational study. Clinical and tomographic evaluation of patients was performed before, after 6 and 18 months of BMT, for patients submitted to the procedure between 2011 and 2017. The quantitative analysis of HRCT scans was performed using a fully automated program (Yacta), capable of obtaining lung volume, density and attenuation percentiles (P10, P40, P50, P80 and P90). Clinical data, including the results of spirometry, were obtained from patients\' electronic records. Forced vital capacity (FVC) at 18 months was used to classify patients into \"best response\" group (>= 10% increase in FVC values) or \"stable response\" (reduction, stability or FVC increase < 10%). No patient had FVC reduction > 10% after BMT. Thirty-three patients were included, with tomographic or pulmonary function alterations before the BMT. The \"best response\" group consisted of 15 patients (45.4%, 4 men, mean age 32.1 years), while the \"stable response\" group comprised 18 patients (54.6%, 4 men, mean age of 37.5 years). Quantitative analysis of HRCT did not show a significant difference between the groups in the pre-BMT evaluation. In the \"best response\" group there was a significant reduction in mean lung density and density percentile values after BMT, with emphasis on the 80th and 90th percentiles. In the \"stable response\" group there was no significant post-BMT change in lung volumes and pulmonary densities. We conclude that the quantitative automatic HRCT analysis of patients with ES identified a significant reduction in pulmonary density in patients with improved pulmonary function. We speculate that, in addition to the mean volumes and densities, density percentiles may also be used as a parameter in the follow-up ofpatients with interstitial lung disease. This tool may represent a biomarker in the evaluation of interstitial lung disease treatment in patients with SSc, complementing pulmonary function tests.
23

Estudo funcional do acometimento das pequenas vias aéreas nas pneumopatias intersticiais fibrosantes / Physiological study of small airwayfunction in fibrosing interstitial lung disease

Salge, João Marcos 23 February 2007 (has links)
Apesar de bem estabelecido em termos morfológicos, a repercussão funcional do envolvimento das pequenas vias aéreas nas pneumopatias intersticiais fibrosantes (PIF) permanece controversa. O presente estudo avaliou de maneira invasiva e não-invasiva (espirometria, volume de fechamento, variação da complacência dinâmica com a freqüência respiratória) a função das pequenas vias aéreas em portadores de PIF, comparando com grupo controle e correlacionando com índices morfométricos de biópsias. Os testes funcionais não diferenciaram portadores da doença dos controles quanto ao acomentimento das pequenas via aéreas e não se correlacionaram com os dados morfométricos / Although well known involvement of small airway in fibrosing interstitial lung disease based on morfologic issues, its functional consequences remains controversial. We present an invasive and non-invasive physiologic study for small airway function (pulmonary function tests, closing volume and frequency dependence of dynamic compliance) in patients with lung fibrosis. The physiological data were compared with normal controls and correlated with morfometric measurements from biopsies. Specific small airway function data could not show obstructive pattern when compared with normals, and did not correlate with morofmetric data
24

Der Nachweis von Plasmazytoiden Monozyten in der Bronchoalveolären Lavage - Methodik und klinische Bedeutung

Mahlig, Kirsten 12 July 1999 (has links)
Die Rationale für immuntherapeutische Ansätze zur Behandlung maligner Neoplasien geht davon aus, daß Tumore über spezifische Tumorantigene verfügen. Dendritische Zellen als die wichtigsten antigenpräsentierenden Zellen sind in der Lage, Tumorantigene naiven T-Zellen zu präsentieren und spezifische zytotoxische T-Zellen zu stimulieren. In der vorliegenden Arbeit wurden dendritische Zellen durch Stimulation mit Interleukin-4 (IL-4) und Granulozyten/ Makrophagen Koloniestimulierender Faktor (GM-CSF) aus peripheren mononukleären Blutzellen gesunder Spender und an Tumoren des gastroenteropankreatischen Systems erkrankter Patienten generiert. Mit den dendritischen Zellen cokultivierte immunologische Effektorzellen (Zytokin- induzierte Killerzellen, CIK-Zellen) wurden im Zytotoxizitätstest gegen kolorektale und pankreatische Karzinomzellen eingesetzt. CIK-Zellen sind zytototoxische Zellen, die durch Stimulation mit Zytokinen aus peripheren Blutlymphozyten erzeugt werden. Durch die Cokultivierung der Effektorzellen mit dendritischen Zellen konnte eine signifikante Steigerung der unspezifischen zytotoxischen Wirkung der CIK-Zellen bewirkt werden. Zur Steigerung der spezifischen Zytotoxizität wurden dendritische Zellen mit dem Gesamtprotein der tumor- assoziierten Antigene cancer associated antigen (CA 19-9) und carcinoembryonic antigen (CEA) gepulst. Effektorzellen zeigten nach der Cokultur mit gepulsten dendritischen Zellen zytotoxische Wirkung gegen Targetzellen, die das zum Pulsen verwendete Tumorantigen auf der Zelloberfläche exprimieren. Die Antigenspezifität der zytotoxischen Wirkung konnte durch eine signifikant verminderte Zellyse nach Blockade des Tumorantigens auf den Targetzellen belegt werden. Erstmals beschrieben ist hier das Pulsen dendritischer Zellen mit sowohl autologen als auch allogenen Seren von Patienten mit erhöhten Tumormarkerspiegeln. Eine Kultivierung dendritischer Zellen in tumormarkerhaltigem Serum bewirkte dosisabhängig eine verstärkte zytotoxische Wirkung cokultivierter Effektorzellen gegen Tumorzellen. Die verstärkte Zellyse zeigte sich unabhängig vom allogenem oder autologem Charakter des Serums. Der immunstimulierende Effekt des Patientenserums konnte durch eine vorhergehende Hitzeinaktivierung des Serums neutralisiert werden. Die höchsten Zellysen wurden durch eine Kultivierung dendritischer Zellen in tumormarkerhaltigem Serum und zusätzlichem Pulsen mit exogenem Tumorantigen erreicht. Untersuchungen an komplett autologen Systemen reproduzierten die an Zellkulturen erhobenen Befunde. Hierfür wurden erfolgreich Primärkulturen kolorektaler Tumore etabliert.Aus dem Blut von Tumorpatienten wurden dendritische Zellen generiert, die mit autologem Serum kultiviert wurden. Die cokultivierten autologen Effektorzellen erwiesen sich im Zytotoxizitätstest gegen autologe Tumorzellen als zytotoxisch. Die Cokultivierung der Effektorzellen mit den dendritischen Zellen bewirkte bei beiden Zellpopulationen Veränderungen. Dendritische Zellen zeigten nach der Cokultur eine verstärkte Expression antigenpräsentierender und costimulatorischer Moleküle. Bei den CIK-Zellen kam es zu einem Anstieg der Proliferationsrate. Bei Untersuchungen zur Antigenspezifität von T-Zellrezeptoren konnte vermehrt antigenspezifischer T-Zellrezeptor nachgewiesen werden. Des weiteren stieg das Verhältnis zwischen zytotoxischen T-Zellen und T-Helferzellen zugunsten der zytotoxischen T-Zellen. In ELISpot-Untersuchungen wurde eine Zunahme Interferon-gamma sezernierender CIK-Zellen nachgewiesen. Dendritische Zellen ließen sich erfolgreich mit inaktiviertem Adenovirus, an das kovalent Poly-L-Lysin gekoppelt ist, transfizieren. Die für den adenoviralen Gentransfer benötigten Oberflächenstrukturen konnten auf dendritischen Zellen nachgewiesen werden. Zur Verbesserung der Zytotoxizität wurden dendritische Zellen erfolgreich mit dem Gen für den Transaktivator CIITA transfiziert. CIITA- transfizierte dendritische Zellen exprimierten vermehrt MHC Klasse II-Moleküle. Die transduzierten dendritischen Zellen induzierten bei cokultivierten Effektorzellen eine erhöhte unspezifische Zytotoxizität. Mit Tumorantigen gepulste dendritische Zellen können bei der Entwicklung immuntherapeutischer Protokolle bei malignen Neoplasien von Bedeutung sein. / The immunotherapeutic approach against malignant neoplasias appreciates that tumours encode tumour rejection antigens, that enable them to induce protective immunity. Dendritic cells are major antigen-presenting cells and are able to present tumour antigens to naive T-cells and stimulate cytotoxic T-cells in a specific manner. In the present graduation-manuscript dendritic cells were generated in the presence of Interleukin-4 and granulocyte/macrophage colony-stimulating factor (GM-CSF) from peripheral mononuclear blood cells of healthy donors and tumour-patients. Immunological effector cells termed cytokine-induced killer cells (CIK cells) were co-cultured with dendritic cells and tested for their cytotoxic capacity against colorectal and pancreatic cancer cell-lines in a LDH-release assay. CIK cells are cytotoxic lymphocytes generated by incubation of peripheral blood lymphocytes with different cytokines. Co-culture of effector cells with dendritic cells led to a significant increase of the cytotoxic effect of CIK cells. For a further increase of specific cytotoxicity dendritic cells were pulsed with total protein of the tumour-associated antigens cancer associated antigen CA 19-9 and carcinoembryonic antigen (CEA). Co-cultured effector cells showed an increase in cytotoxicity against tumour-antigen expressing target cells, after co-culture with pulsed dendritic cells. The specificity of the cytotoxic effect could be shown by blocking the tumour-antigens with a monoclonal antibody. Autologous and allogenec untreated serums from patients with elevated tumour-marker levels were also used for pulsing of dendritic cells. Similar to the results when using total protein for pulsing, a cultivation in serum of patients with elevated tumour marker levels caused an intensified cytotoxic effect of effector cells against tumour cells in a dose-dependent manner. The intensified cytotoxicity was seen independent of the allogenec or autologous character of the serum. The immuno-stimulating effect of the patient serum could be neutralized by preceding heat inactivating. The highest cytotoxicity was achieved by a cultivation of dendritic cells in serum from patients with elevated tumour marker levels and additional pulsing with exogenous tumour antigen. Experiments with completely autologous systems reproduced the results made with cell-lines. Primary cultures of colorectal tumours were established. Dendritic cells were generated from the blood of tumour patients and were cultivated in autologous serum. Co-cultured autologous effector cells showed cytotoxicity when used against autologous tumour cells. Co-culturing of effector cells with dendritic cells caused modifications at both cell populations. Dendritic cells showed an increase expression of antigen-presenting and co-stimulatory molecules. CIK cells showed a higher proliferation-rate when co-cultured. They express more antigen-specific T-cell receptor, and the cytotoxic T-cells to T-helper cells ratio increased. ELISpot-assays showed an increase of interferon gamma producing cells. Dendritic cells were successfully transduced by using an inactivated adenovirus, which covalently binds poly-L-lysine. Dendritic cells express the molecules that enables adenoviral gene delivery on their surface. For the improvement of cytotoxicity dendritic cells were transduced with the gene encoding for the transactivator CIITA. CIITA transduced dendritic cells increases expression of MHC class II molecules. Cytotoxicity experiments with transduced dendritic cells resulted in an increased induction of non-specific cytolysis from co-cultured effector cells. DC pulsed with tumour-antigens may have a major impact on immunotherapeutic protocols for cancer patients.
25

Estudo funcional do acometimento das pequenas vias aéreas nas pneumopatias intersticiais fibrosantes / Physiological study of small airwayfunction in fibrosing interstitial lung disease

João Marcos Salge 23 February 2007 (has links)
Apesar de bem estabelecido em termos morfológicos, a repercussão funcional do envolvimento das pequenas vias aéreas nas pneumopatias intersticiais fibrosantes (PIF) permanece controversa. O presente estudo avaliou de maneira invasiva e não-invasiva (espirometria, volume de fechamento, variação da complacência dinâmica com a freqüência respiratória) a função das pequenas vias aéreas em portadores de PIF, comparando com grupo controle e correlacionando com índices morfométricos de biópsias. Os testes funcionais não diferenciaram portadores da doença dos controles quanto ao acomentimento das pequenas via aéreas e não se correlacionaram com os dados morfométricos / Although well known involvement of small airway in fibrosing interstitial lung disease based on morfologic issues, its functional consequences remains controversial. We present an invasive and non-invasive physiologic study for small airway function (pulmonary function tests, closing volume and frequency dependence of dynamic compliance) in patients with lung fibrosis. The physiological data were compared with normal controls and correlated with morfometric measurements from biopsies. Specific small airway function data could not show obstructive pattern when compared with normals, and did not correlate with morofmetric data
26

Redes neurais auto-organizáveis na caracterização de lesões intersticiais de pulmão em radiografia de tórax / Self-organizing neural networks in the characterization of interstitial lung diseases in chest radiographs.

Ambrosio, Paulo Eduardo 01 June 2007 (has links)
O desenvolvimento tecnológico proporciona uma melhoria na qualidade de vida devido à facilidade, rapidez e flexibilidade no acesso à informação. Na área biomédica, a tecnologia é reconhecidamente uma importante aliada, permitindo o rápido desenvolvimento de métodos e técnicas que auxiliam o profissional na atenção à saúde. Recentes avanços na análise computadorizada de imagens médicas contribuem para o diagnóstico precoce de uma série de doenças. Nesse trabalho é apresentada uma metodologia para o desenvolvimento de um sistema computacional para caracterização de padrões em imagens pulmonares, baseado em técnicas de redes neurais artificiais. No estudo, buscou-se verificar a utilização de redes neurais auto-organizáveis como ferramenta de extração de atributos e redução de dimensionalidade de imagens radiográficas de tórax, objetivando a caracterização de lesões intersticiais de pulmão. Para a redução de dimensionalidade e extração de atributos, implementou-se um algoritmo baseado nos mapas auto-organizáveis (SOM), com algumas variações, obtendo-se uma redução dos cerca de 3 milhões de pixels que compõe uma imagem, para 240 elementos. Para a classificação dos padrões, utilizou-se uma rede Perceptron multi-camadas (MLP), validada com a metodologia leave-one-out. Com uma base contendo 79 exemplos de padrão linear, 37 exemplos de padrão nodular, 30 exemplos de padrão misto, e 72 exemplos de padrão normal, o classificador obteve a média de 89,5% de acerto, sendo 100% de classificação correta para o padrão linear, 67,5% para o padrão nodular, 63,3% para o padrão misto, e 100% para o padrão normal. Os resultados obtidos comprovam a validade da metodologia. / The technological development provides an improvement in the quality of life due to easiness, speed and flexibility in the access to the information. In the biomedical area, the technology is admitted as an important allied, allowing the fast development of methods and techniques that assist the professional in the health care. Recent advances in the computerized analysis of medical images contribute for the precocious diagnosis of a series of diseases. In this work a methodology for the development of a computational system for characterization of patterns in pulmonary images, based in techniques of artificial neural networks is presented. In the study, has searched for the verification the use of self-organizing neural networks as a feature extraction and dimensionality reduction tool of chest radiographs, willing to characterize interstitial lung disease. For the dimensionality reduction and feature extraction, an algorithm based on Self-Organizing Maps (SOM) was implemented, with some variations, getting a reduction of about 3 million pixels that it composes an image, for 240 elements. For the pattern classification, a Multilayer Perceptron (MLP) was used, validated with the leave-one-out methodology. With a database containing 79 samples of linear pattern, 37 samples of nodular pattern, 30 samples of mixed pattern, and 72 samples of normal pattern, the classifier provided an average result of 89.5% of right classification, with 100% of right classification for linear pattern, 67.5% for nodular pattern, 63.3% for mixed pattern, and 100% for normal pattern. The results prove the validity of the methodology.
27

Estudo do remodelamento ativo da matriz extracelular pulmonar na esclerose sistêmica / Study of active pulmonary matrix remodeling process in systemic sclerosis

Erika Franco de Carvalho 11 February 2008 (has links)
Introdução: A doença intersticial pulmonar é um importante fator prognóstico na esclerose sistêmica (ES). O prognóstico das pneumonias intersticiais não específicas (NSIP) associadas às colagenoses tem sido descrito como melhor do que o da forma idiopática. Levanta-se a hipótese de que o processo de remodelamento e reparo do parênquima pulmonar nessas duas formas da doença sejam diferentes. Objetivos: Comparar os mecanismos de reparo e remodelamento entre a NSIP associada a ES e a NSIP idiopática. Observar o impacto dos mesmos nas provas de função pulmonar e na sobrevida. Métodos: Foram analisadas 40 biópsias de pacientes com o diagnóstico de NSIP (18 biópsias de NSIP associada a ES e 22 na forma idiopática). As informações clínicas e as provas de função pulmonar foram obtidas através da revisão dos prontuários. As lâminas foram revisadas por três patologistas. Foram comparadas as densidades epitelial, vascular, bem como a atividade vascular dos dois grupos utilizando o método de imuno-histoquímica. Para isso foram utilizados os anticorpos anti- citoqueratina 7 (CK-7), anti- proteína-a do surfactante (SP-A), antimarcador de célula endotelial CD-34 (CD34), e anti-molécula da adesão vascular 1 (VCAM-1). Também foi comparado o padrão de remodelamento da matriz septal e vascular, usando os métodos histoquímicos da resorcina (fibras elásticas) e picrosírius (colágeno). Uma análise estatística foi realizada comparando os resultados dos dois grupos, o impacto do remodelamento nas provas de função pulmonar e a influência na sobrevida. Resultados: A densidade das células epiteliais foi menor na NSIP-ES, do que na forma idiopática (p<0,0001). Já os pneumócitos tipo II e as células de Clara encontraram-se diminuídos no grupo idiopático (p=0,02). Uma diminuição na densidade vascular foi encontrada na NSIP-ES quando comparada à forma idiopática (p<0,0001); no entanto, a atividade vascular medida pelo VCAM-1 foi maior no grupo da NSIP-ES (p<0.0001). O conteúdo das fibras elásticas e colágeno septal, bem como o das fibras elásticas na parede vascular, estavam aumentados no grupo da ES quando comparados à forma idiopática (p=0,01; p=0,001 e p<0,0001, respectivamente). Não houve diferença estatística entre o colágeno da parede vascular, no grau de obstrução vascular ou associação entre os parâmetros de remodelamento e reparo do parênquima pulmonar na sobrevida dos dois grupos. Dentre as provas de função pulmonar, a DCO/Hb foi mais afetada no grupo da ES (59% do valor predito na ES e 97% no grupo idiopático). Foi observada uma associação direta entre a densidade vascular e a DCO/Hb (p=0,02). Após o seguimento de 36 meses, não foi observada diferença no prognóstico dos dois grupos. Conclusão: Os processos de remodelamento e reparo do parênquima pulmonar parecem ser diferentes entre os dois grupos. Apesar de o processo fibrótico ser mais intenso na NSIP-ES, isso parece não estar associado a um pior prognóstico, como tem sido descrito na forma idiopática. Como o processo de elastose e a expressão do VCAM-I são mais intensos na ES, isso sugere que o processo inflamatório tem um papel mais importante na patogênese e no processo de remodelamento e reparo da ES do que na forma idiopática. No entanto, outros estudos são necessários para validar a importância desses resultados e sua utilização para fins terapêuticos e de prognóstico / Background: The presence of Interstitial lung disease is a well recognized prognostic factor in systemic sclerosis (SSc). As the prognosis in nonspecific interstitial pneumonia (NSIP) has been described to be better in collagen vascular disorders compared to the idiopathic forms, it is conceivable that the mechanisms of repair and remodeling are different between these two forms of the disease. Objectives: To compare the mechanisms of repair and remodeling between SSc associated nonspecific pneumonia and the idiopathic form, as well as their impact on pulmonary function tests and survival rates. Methods: Biopsies from 18 patients with SSc-associated NSIP and 22 with idiopathic NSIP were analyzed. Clinical data and pulmonary function test results were obtained by retrospective chart review. All H&E slides were reviewed by three pathologists. The epithelial and vascular densities and vascular activity were compared between the two groups by immunohistochemistry with antibodies directed against cytokeratin-7, surfactant protein-a, CD34, and VCAM-1, as well as septal and vascular matrix remodeling using histochemical stains (picrosirius and resorcin). Statistical analyses were performed to compare the results of these various studies with clinical parameters (e.g. pulmonary function tests) and survival between the groups. Results: Epithelial cell density was lower in SSc-NSIP when compared with idiopathic-NSIP (p<0.0001). Type II pneumocytes and Clara cells were reduced in idiopathic NSIP (p=0.02). A decrease in microvessel density was found in SSc-NSIP compared to idiopathic-NSIP (p<0.0001). The vascular activity measured by VCAM-1 expression was higher in NSIP-SSc when compared to the idiopathic group (p<0.0001). A direct association between vascular density and DLCO/HB was found (p=0.02). Among pulmonary function tests the DLCO/HB was affected to a greater extent in the SSc group (59% of the predicted value in SSc and 97% in the idiopatic group). The content of septal collagen and elastic fibers, as well as the elastic fibers in the vascular wall, were higher in the SSc group (p=0.01, p=0.001 and p<0.0001, respectively). There were no differences in the collagen content of the vascular wall, vascular grade, or survival between the two groups. There was no difference in the survival rate between the two groups after a follow-up of 36 months. Conclusions: Alterations in the pulmonary epithelium and vasculature seem to differ in the SSc-NSIP when compared to the idiopathic form of the disease. Although the fibrotic process is more intense in the SSc group, it does not seem to affect the prognosis of these patients, contrary to what has been described in idiopatic lung fibrosis. Because the elastotic process and VCAM-1 expression are higher in the SSc group, this might suggest that inflammatory mechanisms affecting the elastic fiber system and vasculature could play a greater role in the pathogenesis and pulmonary remodeling process of SSc-NSIP than in idiopathic-NSIP. Further studies may be required to assess the significance of these findings and explore if they can provide prognostic and/or treatment information
28

Estudo do remodelamento ativo da matriz extracelular pulmonar na esclerose sistêmica / Study of active pulmonary matrix remodeling process in systemic sclerosis

Carvalho, Erika Franco de 11 February 2008 (has links)
Introdução: A doença intersticial pulmonar é um importante fator prognóstico na esclerose sistêmica (ES). O prognóstico das pneumonias intersticiais não específicas (NSIP) associadas às colagenoses tem sido descrito como melhor do que o da forma idiopática. Levanta-se a hipótese de que o processo de remodelamento e reparo do parênquima pulmonar nessas duas formas da doença sejam diferentes. Objetivos: Comparar os mecanismos de reparo e remodelamento entre a NSIP associada a ES e a NSIP idiopática. Observar o impacto dos mesmos nas provas de função pulmonar e na sobrevida. Métodos: Foram analisadas 40 biópsias de pacientes com o diagnóstico de NSIP (18 biópsias de NSIP associada a ES e 22 na forma idiopática). As informações clínicas e as provas de função pulmonar foram obtidas através da revisão dos prontuários. As lâminas foram revisadas por três patologistas. Foram comparadas as densidades epitelial, vascular, bem como a atividade vascular dos dois grupos utilizando o método de imuno-histoquímica. Para isso foram utilizados os anticorpos anti- citoqueratina 7 (CK-7), anti- proteína-a do surfactante (SP-A), antimarcador de célula endotelial CD-34 (CD34), e anti-molécula da adesão vascular 1 (VCAM-1). Também foi comparado o padrão de remodelamento da matriz septal e vascular, usando os métodos histoquímicos da resorcina (fibras elásticas) e picrosírius (colágeno). Uma análise estatística foi realizada comparando os resultados dos dois grupos, o impacto do remodelamento nas provas de função pulmonar e a influência na sobrevida. Resultados: A densidade das células epiteliais foi menor na NSIP-ES, do que na forma idiopática (p<0,0001). Já os pneumócitos tipo II e as células de Clara encontraram-se diminuídos no grupo idiopático (p=0,02). Uma diminuição na densidade vascular foi encontrada na NSIP-ES quando comparada à forma idiopática (p<0,0001); no entanto, a atividade vascular medida pelo VCAM-1 foi maior no grupo da NSIP-ES (p<0.0001). O conteúdo das fibras elásticas e colágeno septal, bem como o das fibras elásticas na parede vascular, estavam aumentados no grupo da ES quando comparados à forma idiopática (p=0,01; p=0,001 e p<0,0001, respectivamente). Não houve diferença estatística entre o colágeno da parede vascular, no grau de obstrução vascular ou associação entre os parâmetros de remodelamento e reparo do parênquima pulmonar na sobrevida dos dois grupos. Dentre as provas de função pulmonar, a DCO/Hb foi mais afetada no grupo da ES (59% do valor predito na ES e 97% no grupo idiopático). Foi observada uma associação direta entre a densidade vascular e a DCO/Hb (p=0,02). Após o seguimento de 36 meses, não foi observada diferença no prognóstico dos dois grupos. Conclusão: Os processos de remodelamento e reparo do parênquima pulmonar parecem ser diferentes entre os dois grupos. Apesar de o processo fibrótico ser mais intenso na NSIP-ES, isso parece não estar associado a um pior prognóstico, como tem sido descrito na forma idiopática. Como o processo de elastose e a expressão do VCAM-I são mais intensos na ES, isso sugere que o processo inflamatório tem um papel mais importante na patogênese e no processo de remodelamento e reparo da ES do que na forma idiopática. No entanto, outros estudos são necessários para validar a importância desses resultados e sua utilização para fins terapêuticos e de prognóstico / Background: The presence of Interstitial lung disease is a well recognized prognostic factor in systemic sclerosis (SSc). As the prognosis in nonspecific interstitial pneumonia (NSIP) has been described to be better in collagen vascular disorders compared to the idiopathic forms, it is conceivable that the mechanisms of repair and remodeling are different between these two forms of the disease. Objectives: To compare the mechanisms of repair and remodeling between SSc associated nonspecific pneumonia and the idiopathic form, as well as their impact on pulmonary function tests and survival rates. Methods: Biopsies from 18 patients with SSc-associated NSIP and 22 with idiopathic NSIP were analyzed. Clinical data and pulmonary function test results were obtained by retrospective chart review. All H&E slides were reviewed by three pathologists. The epithelial and vascular densities and vascular activity were compared between the two groups by immunohistochemistry with antibodies directed against cytokeratin-7, surfactant protein-a, CD34, and VCAM-1, as well as septal and vascular matrix remodeling using histochemical stains (picrosirius and resorcin). Statistical analyses were performed to compare the results of these various studies with clinical parameters (e.g. pulmonary function tests) and survival between the groups. Results: Epithelial cell density was lower in SSc-NSIP when compared with idiopathic-NSIP (p<0.0001). Type II pneumocytes and Clara cells were reduced in idiopathic NSIP (p=0.02). A decrease in microvessel density was found in SSc-NSIP compared to idiopathic-NSIP (p<0.0001). The vascular activity measured by VCAM-1 expression was higher in NSIP-SSc when compared to the idiopathic group (p<0.0001). A direct association between vascular density and DLCO/HB was found (p=0.02). Among pulmonary function tests the DLCO/HB was affected to a greater extent in the SSc group (59% of the predicted value in SSc and 97% in the idiopatic group). The content of septal collagen and elastic fibers, as well as the elastic fibers in the vascular wall, were higher in the SSc group (p=0.01, p=0.001 and p<0.0001, respectively). There were no differences in the collagen content of the vascular wall, vascular grade, or survival between the two groups. There was no difference in the survival rate between the two groups after a follow-up of 36 months. Conclusions: Alterations in the pulmonary epithelium and vasculature seem to differ in the SSc-NSIP when compared to the idiopathic form of the disease. Although the fibrotic process is more intense in the SSc group, it does not seem to affect the prognosis of these patients, contrary to what has been described in idiopatic lung fibrosis. Because the elastotic process and VCAM-1 expression are higher in the SSc group, this might suggest that inflammatory mechanisms affecting the elastic fiber system and vasculature could play a greater role in the pathogenesis and pulmonary remodeling process of SSc-NSIP than in idiopathic-NSIP. Further studies may be required to assess the significance of these findings and explore if they can provide prognostic and/or treatment information
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Systemic sclerosis : vascular, pulmonary and immunological aspects

Neumann Andersen, Grethe January 2008 (has links)
In systemic sclerosis (SSc), interstitial lung disease (ILD) and engagement of the vascular system lead to increased morbidity and mortality. The aim of this thesis was to elucidate, in a consecutively included cohort of SSc (limited and diffuse) patients (n = 33), the T cell cytokine profile driving the disease in ILD and to explore the role of matrix metalloproteinase 9 (MMP-9) and its inhibitor: tissue inhibitor of metalloproteinase 1 (TIMP-1) in the extracellular matrix (ECM) degrading process leading to fibrous scarring and honey combing. Moreover, to characterize the role of nitric oxide (NO) in vascular engagement. Peripheral arterial changes cause Raynaud’s phenomenon and digital ulcers. Nitric oxide (NO) a main inducer of vasodilation is produced by endothelial nitric oxide synthase (eNOS) in response to changes in blood flow or by inflammatory cytokine inducible (i) NOS. In the vascular smooth muscle cell (VSMC) NO activates guanylate cyclase to produce cGMP, causing relaxation. We showed elevated plasma nitrate, a degradation product of NO, and increased urinary excretion of nitrate and cGMP. Plasma nitrate correlated with elevated levels of endothelial adhesion molecules: endothelial (E) selectin and vascular adhesion molecule 1, indicating that the activated endothelium is the site of NO synthesis by iNOS. Endothelial staining for E-selectin and the finding of iNOS and eNOS in SSc skin biopsies supported this notion. In SSc increased vascular stiffness may limit the NO vasodilatory effects. We found normal endothelium-dependent (i.e. flow mediated (FMD%)) and endothelium-independent (i.e. nitroglycerin-induced (NTG%)) vasodilation in the brachial artery. Radial arterial wall stiffness measured as maximum increase in pulse pressure (dP/dtmax) was increased. FMD% and especially NTG% correlated negatively and dP/dtmax positively to measures of endothelial inflammation: plasma- nitrate and adhesion molecule levels. Thus inflammatory vascular wall changes may interfere with dilation as may the presence of nitrate tolerance. We found elevated alveolar MMP-9 in both its pro- and active form in ILD. The levels correlated to decline in lung capacity, pointing at a causal relation. We suggest that neutrophils secrete MMP-9, which may degrade collagen IV, (the main constituent of basal membranes), collagen V, gelatins, proteoglycans and elastin. MMP-9 activity is partly regulated by the binding of pro- and active form to TIMP-1. Alveolar TIMP-1, which even stimulates fibroblast ECM synthesis, was increased independent of ILD. The inflammatory process in ILD is orchestrated by activated T helper (h) lymphocytes. We found a mixed Th1/Th2 reaction in SSc alveolar T cells expressing messenger for interferon gamma (Th1), IL-6 and IL-10 (both Th2). No particular cytokine mRNA profile distinguished alveolar T cells in ILD. Neutrophils invaded the bronchial epithelium, which seemed otherwise inert as levels of inflammatory cytokine sensitive transcription factors and their nuclear translocation tended to be low. The neutrophil recruitment pathway is uncertain as chemoattractants and endothelial adhesion molecules were normally expressed. In conclusion, MMP-9 probably causes degradation of lung tissue in ILD and may represent a future therapeutic target. Alveolar T cells show a mixed Th1/Th2 cytokine profile independent of ILD. Neutrophils invade the bronchial epithelium. Activated endothelium produces increased amounts of NO and adhesion molecules and the level of activation influences brachial arterial FMD% and NTG% and radial arterial compliance. Nitrate tolerance may be present.
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BAFF (B-cell activating factor of the TNF family) u nemocných s idiopatickými zánětlivými myopatiemi se zřetelem na autoprotilátkový profil. / BAFF (B-cell Activating Factor of the TNF Family) in patients with idiopathic inflammatory myopathieswith respect to autoantibody profile.

Kryštůfková, Olga January 2018 (has links)
The idiopathic inflammatory myopathies (IIMs) are a heterogeneous group of chronic muscle diseases with frequent extramuscular organ involvement that contributes to serious prognosis. The presence of autoantibodies and composition of muscle infiltrates both support autoimmune nature of the disease and pathogenic role of B lymphocytes. Besides the traditional diagnostic subgroups, autoantibody characterised phenotype subsets have been identified with presumed similar pathogenic mechanisms. The best known is the antisynthetase syndrome which is characterised by presence of myositis, antisynthetase autoantibodies (with anti-Jo-1 being the most frequent), interstitial lung disease and other extramuscular manifestations. BAFF (B cell-Activating Factor of the TNF Family) is a key factor in B cell homeostasis modulation. In high levels, it allows survival of autoreactive B cell clones and thus participates in the pathogenesis of autoimmune diseases. Its expression is induced by type I interferons (IFN-1). The aim of the PhD thesis was to explore the role of BAFF in pathogenesis of IIMs by analysis of its serum levels, the receptors for BAFF in muscle tissue, their associations to IFN-1 and expression of BAFF gene mRNA transcription variants in peripheral blood cells. Further aspect was to study a possible...

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