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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.
381

Efeito da metformina sobre IL-8 e IL-1b em um modelo de células estromais endometriais hiperinsulinêmicas e hiperandrogênicas in vitro

Machado, Amanda de Barros January 2013 (has links)
O endométrio é a mucosa que reveste o útero. A receptividade uterina é definida como um estado em que o endométrio se encontra receptivo à implantação do blastocisto. E, a preparação do endométrio para a implantação não é somente uma questão de estimulação hormonal adequada, depende da interação entre o blastocisto e o endométrio. Esta interação envolve uma complexa sequência de eventos de sinalização e uma variedade de moléculas. As concentrações de interleucina-8 (IL-8) e interleucina-1β (IL-1β) estão correlacionadas com o processo de implantação. Em humanos, a taxa de insucesso desse processo é alta e ocasionada por diversos fatores. A síndrome dos ovários policísticos (SOP) é um distúrbio endócrino-ginecológico que afeta de 6 a 8 % das mulheres em idade reprodutiva, e se caracteriza, principalmente, por anovulação crônica e hiperandrogenismo, estando diretamente relacionada à infertilidade feminina. Apesar da incerteza sobre a causa primária da SOP, há relatos sobre a importância da hiperinsulinemia na sua promoção. O objetivo deste trabalho foi estabelecer um modelo de hiperinsulinemia e hiperandrogenismo em células estromais endometriais in vitro, simulando características de SOP; identificar o melhor gene normalizador para estudos de expressão gênica em amostras das células em cultivo; avaliar o efeito da metformina sobre a proliferação celular e expressão gênica da IL-8 e IL-1β no modelo proposto. O tecido endometrial foi obtido de pacientes submetidas a histerectomia. A cultura primária das células estromais foi padronizada e as células foram divididas em sete grupos de tratamento: estradiol (G1); estradiol e progesterona (G2); estradiol, progesterona e insulina (G3); estradiol, progesterona e diidrotestosterona (G4); estradiol, progesterona e metformina (G5); estradiol, progesterona, insulina e diidrotestosterona (G6); estradiol, progesterona, insulina, diidrotestosterona e metformina (G7). Foi realizada análise de imunocitoquímica para vimentina para confirmação do cultivo com células estromais. Para avaliar a viabilidade e proliferação celular ao longo do tempo foi utilizado o ensaio de MTT em dois tempos diferentes de cultivo. As extrações de RNA foram realizadas e o cDNA obtido das amostras foi utilizado para a amplificação do mRNA de cinco genes candidatos a normalizadores e para avaliar a expressão dos genes da IL-8 e IL-1β através de PCR em tempo real.O estabelecimento da cultura de células estromais foi confirmado através da coloração positiva para a proteína vimentina. As células mantiveram-se viáveis durante todo o período de cultivo, apresentando aumento significativo na proliferação celular no tempo 8 em relação ao tempo 4 em todos os grupos. O grupo G7 (tratado durante 48 horas com metformina) apresentou uma menor taxa de proliferação em relação aos grupos G2, G3 e G6. Para análise de expressão gênica nestas células, o gene que mostrou os melhores parâmetros de estabilidade de expressão no modelo celular proposto foi o gene HPRT1. Observamos uma maior expressão do gene da IL-8 no grupo G5 tratado durante 48 horas em relação ao mesmo grupo tratado durante o período de 24 horas. Verificou-se maior expressão do gene da IL-1β no grupo G5 quando comparado a todos os outros grupos no período de 48 horas de tratamento com metformina. Entretanto, o grupo G7, também tratado com metformina, não apresentou diferença estatística em relação ao tempo de tratamento em nenhum dos genes estudados. Esses resultados demonstram que o modelo de hiperinsulinemia e hiperandrogenismo em cultura de células estromais endometriais é viável. Neste modelo, em que foram testados cinco genes em relação à sua estabilidade de expressão, o gene HPRT1 apresentou uma boa estabilidade, ao contrário de outros genes frequentemente utilizados como genes de referência. O tratamento com metformina apresentou um efeito antiproliferativo nas células do grupo hiperinsulinêmico e hiperandrogênico. No período de 48 horas aumentou a expressão do gene da IL-1β no grupo tratado somente com o medicamento. Sugerindo uma ação inibitória da insulina sobre a expressão dos genes da IL-8 e IL-1β no grupo hiperinsulinêmico e hiperandrogênico. Mais estudos são necessários para melhor entendimento do efeito da metformina nos fatores envolvidos durante a implantação. / The endometrium is the mucosa lining the uterus. The uterine receptivity is defined as a condition in which the endometrium is receptive to implantation of the blastocyst. The preparation of the endometrium for implantation is not only a matter of proper hormonal stimulation, it depends on the interaction between the blastocyst and the endometrium. This interaction involves a complex sequence of events and a variety of signaling molecules. The concentrations of interleukin-8 (IL-8) and interleukin-1β (IL-1β) are correlated to the implantation process. In humans, the failure rate of this process is high and caused by several factors. The polycystic ovary syndrome (PCOS) is an endocrine-gynecological disorder that affects from 6 to 8 % of women of reproductive age. It is characterized mainly by chronic anovulation and hyperandrogenism and directly related to female infertility. Despite the uncertainty about the primary cause of PCOS, there are reports about the importance of hyperinsulinemia in promoting it. The aim of this study was to establish a model of hyperinsulinemia and hyperandrogenism in endometrial stromal cells in vitro, simulating features of PCOS; to identify the best housekeeping gene for gene expression studies in the cultured cells; to evaluate the effects of metformin on cell proliferation, as well as IL-8 and IL-1β gene expression in the proposed culture model. The human endometrial tissue was obtained from patients undergoing hysterectomy. The primary culture of stromal cells was standardized and divided into seven treatment groups: estradiol (G1); estradiol and progesterone (G2); estradiol, progesterone and insulin (G3); estradiol, progesterone and dihydrotestosterone (G4); estradiol, progesterone and metformin (G5); estradiol, progesterone, insulin and dihydrotestosterone (G6); estradiol, progesterone, insulin, dihydrotestosterone and metformin (G7). Immunocytochemistry analysis for vimentin were performed. Cell viability and proliferation were evaluated by MTT assay at two days in different times of cultivation. RNA extractions were performed and the cDNA obtained from primary culture was used to amplify five candidates to housekeeping genes mRNA and to evaluate IL-8 and IL1β expression by real time PCR. The stromal culture cell establishment was confirmed by positive staining for vimentin. The cells remained viable throughout the cultivation period, with significant cell proliferation increase at day 8 compared to day 4 in all groups. The G7 group (metformin treated for 48 hours) showed lower proliferation rate than G2, G3 and G6 groups. For gene expression analysis in these cells, the gene showing the best parameters of stability of expression was HPRT1. Increased gene expression of IL-8 was observed in G5 group treated for 48 hours compared to the same group during 24 hours. Similarly, the G5 group showed higher IL-1β gene expression when compared to all other groups treated with metformin for 48 hours. However, the G7 group, also metformin treated, did not show statistically significant difference in treatment time of any studied genes. These results suggest that model of hyperinsulinemia and hyperandrogenism in endometrial stromal cells is viable and provides a good cell sampling to molecular analysis under different experimental conditions. In this model, several genes were tested for expression stability. HPRT1 presented the best values, unlike others classical housekeeping genes. The metformin treatment showed an antiproliferative effect on cells in hyperinsulinemic and hyperandrogenic group and at 48 hours increased IL-1β gene expression in the treated group with the drug alone. It suggests an inhibitory action of insulin on these genes expression in the hyperinsulinemic and hyperandrogenic group. More studies are needed to better understand the effect of metformin on the factors involved during implantation.
382

Avaliação do papel das citocinas interleucina 32 e interleucina 15 em macrófagos humanos primários infectados com Leishmania (Viannia) braziliensis / Evaluation of the role of the cytokines interleukin 32 and interleukin 15 in primary human macrophages infected with Leishmania (V.) braziliensis

Silva, Lucas Luiz de Lima 13 May 2016 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2016-08-04T19:10:35Z No. of bitstreams: 2 Dissertação - Lucas Luiz de Lima Silva - 2016.pdf: 2502108 bytes, checksum: 9af274c5556e225e1478c978f79254ad (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Erika Demachki (erikademachki@gmail.com) on 2016-08-04T19:11:54Z (GMT) No. of bitstreams: 2 Dissertação - Lucas Luiz de Lima Silva - 2016.pdf: 2502108 bytes, checksum: 9af274c5556e225e1478c978f79254ad (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-04T19:11:54Z (GMT). No. of bitstreams: 2 Dissertação - Lucas Luiz de Lima Silva - 2016.pdf: 2502108 bytes, checksum: 9af274c5556e225e1478c978f79254ad (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-05-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / American Tegumentary Leishmaniasis (ATL) is a disease caused by Leishmania protozoan, belonging to the subgenus Viannia and Leishmania. In Brazil, the most common and prevalent species is L. (V.) braziliensis. In patients with ATL, it was detected the expression of interleukin 32 (IL-32) in skin or mucosal lesions caused by L. Viannia spp. However, the role of IL-32 on ATL is still unclear. It has been shown that IL-15 induces IL-32 and also IL-15 leads to L. infantum control. This study aimed to investigate the effects of IL-32 and IL-15 in the production of cytokines and microbicidal activity of primary human macrophages infected with L. (V.) braziliensis. For this, human peripheral blood monocytes were derived into macrophages and infected with metacyclic forms of L. (V.) braziliensis; evaluation of the infection index (4 h, phagocytosis, 48 h, microbicidal activity) in the absence or presence of rIL-32, rIL-15 or gamma interferon (rIFN) and lipopolysaccharide (LPS); in culture supernatants, IL-32, tumor necrosis factor (TNF) and IL-10 were measured by enzime-linked immunoassay. The addition of rIL-32 to macrophages did not significantly altered phagocytosis of the parasites or microbicidal activity of macrophages. Classical activation of macrophages with rIFN plus LPS decreased the infection index. rIL-32 em high concentration (200 ng/mL) was able to induce TNF in uninfected or infected macrophages, and IL-10 was not induced. Parasites induced lower amounts of intracellular IL-32 as well as rIFN0.1 ng / ml), but there was a synergism between the activation signals provided by the parasites and rIFN (0.1 ng / ml). In the opposite, rIFN in higher concentration (10 ng/mL) induced higher amounts of IL-32, but its activity was partially inhibited by parasites. The rIL-15 was able to induce IL- 32 and TNF in macrophages, but not IL-10 in both non-infected or infected macrophages. The rIL-15 also decreased phagocytosis of parasites by macrophages and increased the microbicidal activity of these cells. The data suggest that IL-15 induces IL-32 and TNF which can contribute to control of the infection. To evaluate the leishmanicidal mechanism pathways induced by IL-15 and IL-32 can help in the development of new therapies for the control of ATL. / A leishmaniose tegumentar americana (LTA) é uma doença infectoparasitária causada por protozários Leishmania, pertencentes aos subgêneros Viannia e Leishmania. No Brasil, a espécies mais comum e prevalente é L. (V.) braziliensis. Em pacientes com LTA, foi detectada a expressão da citocina interleucina 32 (IL-32) nas lesões cutâneas ou mucosas causadas por L. Viannia spp. No entanto, o papel da IL-32 na LTA ainda não foi esclarecido. Foi demonstrado que a IL-15 induz IL-32, além disso a IL-15 leva à morte de L. infantum. O presente estudo teve como objetivo investigar os efeitos da IL-32 e IL-15 na produção de citocinas e na atividade microbicida de macrófagos humanos primários infectados com L. (V.) braziliensis. Para isto, foi realizada a derivação de macrófagos humanos a partir de monócitos do sangue periférico de doadores não infectados e infecção com formas metacíclicas de L. (V.) braziliensis; avaliação do índice de infecção (4 h, fagocitose; 48 h, atividade microbicida), na ausência ou presença de tratamento com rIL-32, rIL-15 ou interferon gama (rIFN) e lipopolissacarídeo (LPS); e avaliação da produção de citocinas IL-32, fator de necrose tumoral (TNF) e IL-10, por ensaio imunoenzimático. A adição de rIL-32 às culturas de macrófagos primários infectados com L. (V.) braziliensis não alterou significantemente a fagocitose ou a atividade microbicida das células. A ativação clássica dos macrófagos com rIFN e LPS resultou em uma diminuição do índice de infecção. A rIL-32 em elevada concentração foi capaz de induzir TNF nos macrófagos não infectados ou infectados pelos parasitos L. (V.) braziliensis, sendo que não foi induzida produção de IL- 10. Os parasitos L. (V.) braziliensis induziram baixas quantidades de IL-32 intracelular, assim como rIFN0,1 ng/mL), porém houve sinergismo entre os sinais de ativação fornecidos pelos parasitos e os do rIFN (0,1 ng/mL). O rIFN em uma concentração mais elevada (10 ng/mL) induziu maiores quantidades de IL-32, porém esta indução foi parcialmente inibida pela infecção com os parasitos. A rIL-15 foi capaz de induzir IL-32 nos macrófagos e, além disso, induziu TNF e não induziu a produção de IL-10, tanto nos macrófagos infectados quanto não infectados. A rIL-15 também diminuiu a fagocitose dos parasitos pelos macrófagos e aumentou a atividade microbicida destes. Os dados sugerem que a IL-15 induz IL-32 e TNF que podem contribuir para o controle da infecção. Avaliar as vias de ativação de mecanismos leishmanicidas induzidos pelas IL- 15 e IL-32 podem auxiliar no desenvolvimento de novas terapias para o controle da LTA.
383

Análise da correlação entre condição periodontal e polimorfismos nos genes das citocinas IL-1, IL-6, TNF-alpha e da enzima paraoxonase em indivíduos afetados ou não com Diabetes Melito tipos I e II / Analysis of the correlation between periodontal status and polymorphisms in the IL-1, IL-6, TNF-alpha and paraoxonase enzyme in individuals affected or not with Diabetes type I and II

Messetti, Ana Camila Pereira, 1980- 23 August 2018 (has links)
Orientador: Rebeca de Souza Azevedo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-23T13:31:17Z (GMT). No. of bitstreams: 1 Messetti_AnaCamilaPereira_M.pdf: 2046118 bytes, checksum: 6767fe84e5b25d194bac897de86b23a3 (MD5) Previous issue date: 2013 / Resumo: A doença periodontal (DP) é uma doença inflamatória crônica de ampla distribuição etária e mundial, que resulta da interação entre fatores etiológicos heterogêneos e que pode sofrer influência ambiental e sistêmica, especialmente na presença do diabetes melito (DM). Os mecanismos que envolvem a associação entre o DM e a presença da DP ainda não estão completamente elucidados, mas as características genéticas ou epigenéticas do hospedeiro, como os polimorfismos genéticos, podem influenciar esta relação. Dessa forma, o objetivo deste estudo foi avaliar o envolvimento de polimorfismos nos genes de IL1-? (-889), de IL1-? (+3984), de IL-6 (-174), de TNF-? (-308) e da paraoxanase (-192) e da paraoxonase (-55) no desenvolvimento de DP e DM em um grupo de pacientes brasileiros. Os polimorfismos rs1800587 e rs1143634 no gene IL-1, rs1800796 no gene IL6, rs1800629 no gene TNF-?, e rs662 e rs854560 no gene paraoxanase foram genotipados em 302 adultos, dos quais 96 eram diabéticos com DP (ADM+DP), 20 eram diabéticos com saúde periodontal (ADM-DP), 112 eram normoglicêmicos com DP (AN+DP) e 74 eram normoglicêmicos com saúde periodontal (AN-DP); e em 88 crianças e adolescentes, dos quais 11 eram diabéticos com gengivite (CDM+G), 15 eram diabéticos com saúde gengival (CDM-G), 30 eram normoglicêmicos com gengivite (CN+G) e 32 eram normoglicêmicos com saúde gengival (CN-G). No grupo de pacientes adultos, a presença do alelo T no polimorfismo rs1143634 no gene IL1-? foi mais frequente nos indivíduos ADM+DP que nos indivíduos AN-DP, gerando um OR de 14,9 (95% IC: 8,6-25,9; p<0,0001); a presença do alelo A no polimorfismo rs1800629 no gene TNF-? foi mais frequente nos indivíduos ADM+DP que nos indivíduos AN-DP, gerando um OR de 22,7 (95% IC: 6,96 -74,5 p<0,0001), e a presença do alelo C no polimorfismo rs1800796 no gene IL6 foi mais frequente nos indivíduos ADM+DP que nos indivíduos AN+DP, gerando um risco de recorrência de 2,38 (95% IC:1,61-3,5; p<0,0001), e que nos indivíduos AN-DP, gerando risco de recorrência de 2,87 (1,79-4,5; p<0,0001). No grupo de pacientes crianças e adolescentes, a presença do alelo C no polimorfismo rs1800796 no gene IL-6 foi mais frequente em indivíduos CN+G que nos indivíduos CN-G, gerando um risco de recorrência de 121,1 (95% IC:32,3-145,3; p<0,0001), e foi mais frequente nos indivíduos CDM+G que nos indivíduos CN-G, gerando um risco de recorrência de 104 (95% IC:11,4-136,6; p<0,0001). Os resultados deste estudo evidenciam a associação dos polimorfismos rs1143634 no gene IL1-?, rs1800796 no gene IL6 e rs1800629 no gene TNF-? com a suscetibilidade genética ao desenvolvimento de DP e/ou DM na população adulta estudada; e a associação do polimorfismo rs1800796 no gene IL-6 com a suscetibilidade genética ao desenvolvimento de DP e/ou DM na população de crianças e adolescentes estudada / Abstract: Periodontal disease (PD) is a chronic inflammatory disease of worldwide distribution that may affect all age groups, and results from the interaction between heterogeneous etiologic factors, such as environmental and systemic influence, especially in the presence of diabetes mellitus (DM). Mechanisms involving the association between DM and the presence of PD are still not fully elucidated, but the genetic or epigenetic alterations of the host, such as the genetic polymorphisms may influence this relationship. Thus, the aim of this study was to evaluate the involvement of polymorphisms in the genes of IL1-? (-889), IL1- (+3984), IL-6 (-174), TNF-? (-308) and paraoxanase (-192) and paraoxonase (-55) in PD and/or DM development in a group of Brazilian patients. The polymorphisms rs1800587 and rs1143634 from IL1 gene, rs1800796 form IL6 gene, rs1800629 from TNF-? gene, and rs662 and rs854560 from paraoxanase gene were genotyped in 302 adults, of whom 96 were diabetic with PD (ADM+PD), 20 were diabetics with periodontal health (ADM-PD), 112 were normoglycemic with PD (AN+PD) and 74 were normoglycemic with periodontal health (AN-PD); and in 88 children and adolescents, of whom 11 were diabetic patients with gingivitis (CDM+G), 15 were diabetics with gingival health (CDM-G), 30 were normoglycemic with gingivitis (CN+G) and 32 were normoglycemic with gingival health (CN-G). In the group of adult patients, the presence of T allele at the rs1143634 polymorphism in the IL1-? gene was more frequent in ADM+PD than in AN-PD, generating an OR of 14, 9 (95% CI :14,9-25, 9; p <0.0001), the presence of A allele at the rs1800629 polymorphism in the TNF-? gene was more frequent in ADM+PD than in AN+PD, generating an OR of 22,7 (95% CI 6.96 -74.5; p <0.0001), and the presence of C allele at the rs1800796 polymorphism in the gene IL6 was more frequent in ADM+PD than in AN+PD, generating an OR of 2.38 (95% CI :1,61-3, 5; p <0.0001), and it was more frequent in ADM+PD than in AN-PD, generating an OR of 2.87 (1.79 to 4.5, p <0.0001). In the group of children and adolescents, the presence of C allele at the rs1800796 polymorphism in the IL6 gene is more frequent in NC+G than in NC-G, generating an OR of 121.1 (95% CI :32,3-145, 3; p <0.0001), and it was more frequent in CMD+G than in NC-G, generating an OR of 104 (95% CI :11,4-136,6; p <0.0001). The results of this study show the association of rs1143634 polymorphisms in the IL1-? gene, rs1800796 in the IL6 gene, and rs1800629 in the TNF-? gene with genetic susceptibility to PD and/or DM development in the adult population studied, and association of the polymorphism rs1800796 in the IL6 gene with genetic susceptibility for PD and/or DM development in the children and adolescents population studied / Mestrado / Estomatologia / Mestra em Estomatopatologia
384

En samlad bild över nutidens forskning angående immunmodulatoriska effekter av te

Nilsson, Sofia January 2012 (has links)
Teblad innehåller en mängd substanser som på olika sätt kan påverka biologiska processer i människan. I föreliggande arbete har en sammanställning gjorts utifrån vetenskapliga artiklar över teets antagna effekter på människans immunsystem .Främst har den mest studerade komponenten i te, epigallocatechin gallate, EGCG, undersökts. De variabler som studerats i immunförsvaret är neutrofiler, tumörnekrosfaktor-α, interferon-γ, interleukin-1β, interleukin-2, interleukin-5, interleukin-6, interleukin-8, interleukin-10 ,interleukin-12, interleukin-13, eikosanoidmetabolismen, lymfocyter, makrofager, dendritiskaceller och T-cellsdifferentiering. Sammafattningsvis föreföll te hämma följande: Neutrofilaktiviteten, TNF-α-bildningen, IFN-γ-aktiviteten, stimuli-inducerad IL-β-bildning, IL-8-aktivering och IL-10-bildning. EGCG visades öka dendritiska cellers apoptos och ändra dedenderitiska cellernas morfologi och minska deras förmüga att stimulera T-cellproliferationen. EGCG-behandling av celler ledde till ökad makrofagaktivitet, ökad produktion av T-regceller kontra andra T-cellslinjer. Tebehandling ökade bildningen av IL-12 ochIL-13. EGCGs effekt på IL-6 var tvetydig; enligt en del artiklar påverkade EGCG ej IL-6, medan det enligt andra artiklar antingen ökade eller minskade IL-6-bildningen. Trots att resultaten ej var entydiga kunde slutsatsen att EGCG (och därmed te) utövade immunsupprimerande effekt dras men att det sannolikt krävs betydligt högre koncentrationer än de som är fysiologiskt uppnåbara (1 μM i plasma och 3 mM i tarmen) genom reguljärt tedrickande för att få en avgörande effekt på människans immunsystem. EGCGs hämmnade effekt på immunsystemet kan dock vara av intresse i högre – farmakologiska – koncentrationer genom att EGCG skulle kunna nyttjas som komplement eller alternativ till för närvarande nyttjade immunförtryckande läkemedel som ciklosporin och glukokortikoider.
385

Investigation of the interleukin-10-GAG interaction using molecular simulation methods

Gehrcke, Jan-Philip 06 March 2015 (has links)
Glycosaminoglycans (GAGs) are linear polysaccharides, built of periodically occurring disaccharide units. GAGs are ubiquitous in the extracellular matrix (ECM), where they exhibit multifarious biological activities. This diversity arises from - among others - their ability to interact with and regulate a large number of proteins, such as cytokines, chemokines, and growth factors. As of the huge variety in their chemical configuration, GAGs are further sub-classified into different types (heparin, for instance, is one of these sub-classes). Hence, GAGs are a diverse class of molecules, which surely contributes to the broadness of their spectrum of biological functions. Through varying arrangements of sulfate groups and different types of saccharide units, individual GAG molecules can establish specific atomic contacts to proteins. One of the best-studied examples is antithrombin-heparin, whose biologically relevant interaction requires a specific pentasaccharide sequence. It is valid to assume, however, that various proteins are yet to be discovered whose biological functions are in some way affected by GAGs. In other cases, and this is true for the cytokine interleukin-10 (IL-10), there are already experimental indications for a biologically relevant protein-GAG interaction, but the details are still obscure and the fundamental molecular interaction mechanism has still not been clarified. IL-10 has been shown to bind GAGs. So far, however, no structural detail about IL-10-GAG interaction is known. Function-wise, IL-10 is mainly considered to be immunosuppressive and therefore anti-inflammatory, but it in fact has the pleiotropic ability to influence the immune system in both directions, i.e. it constitutes a complex regulation system on its own. Therefore, the role of GAGs in this system is potentially substantial, but is yet to be clarified. In vitro experiments have yielded indications for GAGs being able to modulate IL-10\'s biological function, and obviously IL-10 and GAGs are simultaneously present in the ECM. This gives rise to the assumption that IL-10-GAG interaction is of biological significance, and that understanding the impact of GAGs on IL-10 biology is important - from the basic research point of view, but also for the development of therapies, potentially involving artificially designed ECMs. A promising approach for obtaining knowledge about the nature of IL-10-GAG interaction is its investigation on the structural level, i.e. the identification and characterization of the molecular interaction mechanisms that govern the IL-10-GAG system. In this PhD project it was my goal to reveal structural and molecular details about IL-10-GAG interaction with theoretical and computational means, and with the help of experiments performed by collaborators in the framework of the Collaborative Research Centre DFG Transregio 67. For achieving this, I developed three methods for the in silico investigation of protein-GAG systems in general and subsequently applied them to the IL-10-GAG system. Parts of that work have been published in scientific journals, as outlined further below. I proposed and validated a systematic approach for predicting GAG binding regions on a given protein, based on the numerical simulation and analysis of its Coulomb potential. One advantage of this method is its intrinsic ability to provide clues about the reliability of the resulting prediction. Application of this approach to IL-10 lead to the observation that its Coulomb attraction for GAGs is significantly weaker than in case of exemplary protein-GAG systems (such as FGF2-heparin). Still, a distinct IL-10-GAG binding region centered on the residues R102, R104, R106, R107 of the human IL-10 sequence was identified. This region can be assumed to play a major role in IL-10-GAG interaction, as described in chapter 3. Molecular docking methods are used to generate binding mode predictions for a given receptor-ligand system. In chapter 4, I clarify the importance of data clustering as an essential step for post-processing docking results and present a clustering methodology optimized for GAG molecules. It allows for a reproducible analysis, enabling systematic comparisons among different docking studies. The approach has become standard procedure in our research group. It has been applied in a variety of studies, and served as an essential tool for studying IL-10-GAG interaction, as described in chapter 3. Motivated by the shortcomings of classical docking approaches, especially with respect to protein-GAG systems, I worked on the development of a molecular dynamics-based docking method with less radical approximations than usually applied in classical docking. The goal was to make the computational model properly account for the special physical properties of GAGs, and to include the effects of receptor flexibility and solvation. The methodology was named Dynamic Molecular Docking (DMD) and published in the Journal of Chemical Information and Modeling-together with a validation study. The subsequent application of DMD in a variety of studies required enormous amounts of computational resources. For tackling this challenge, I established a graphics processing unit-based high-performance computing environment in our research group and developed a software framework for reliably performing DMD studies on this hardware, as well as on other computing resources of the TU Dresden. The investigation of the IL-10-GAG system via DMD was focused on the IL-10-GAG binding region predicted earlier, and made heavy usage of the optimized clustering approach named above. An important result of this endeavor is that IL-10's amino acid residue R107 significantly stands out compared to all other residues and supposedly plays a particularly important role in IL-10-GAG recognition. The collaboration with the NMR laboratory of Prof. Daniel Huster at the Universität Leipzig was fruitful: I post-processed nuclear Overhauser effect data and obtained heparin structure models, which revealed that IL-10-heparin interaction has a measurable impact on the backbone structure of the heparin molecule. These results were published in Glycobiology. In chapter 8, I propose two different scenarios about how GAG-binding to IL-10 might affect its biological function, based on the findings made in this thesis project. In conclusion, a set of methods has been developed, all of which are generically applicable for the investigation of protein-GAG systems. Regarding the IL-10-GAG system, valuable structural insights for increasing the understanding about its molecular mechanisms were derived. These observations pave the way towards unraveling GAG-mediated bioactivity of IL-10, which may then be specifically exploited, for instance in artificial ECMs for improved wound healing.
386

Nekanonické funkce IL-1α / Noncanonical functions of IL-1α

Novák, Josef January 2020 (has links)
1α (IL 1α) is a multifunctional cytokine 1α is 1α independent on the receptor sig 1α is responsible for 1α to the plasma membrane. 1α activates express κB, binds to 1α 1α 1α to the plasma membrane 1α to signal 1α is required for membrane 1α exter 1α anchoring 1α 1α 1α with tumor suppressor p53 following genotoxic stress is further described in human cell 1α coloca
387

Palmitat induzierte Expression von IL-6 und MCP-1 in humanen Detrusormyozyten vs. bakteriell induzierter Entzündungsreaktion - ein möglicher Zusammenhang zwischen diabetischen Stoffwechsel und Infektionen der Harnblase: Palmitat induzierte Expression von IL-6 und MCP-1 in humanen Detrusormyozyten vs. bakteriell induzierter Entzündungsreaktion - ein möglicher Zusammenhang zwischen diabetischen Stoffwechsel und Infektionen der Harnblase

Schlichting, Nadine 31 March 2011 (has links)
Adipöse Patienten und Typ-2-Diabetiker zeigen ein erhöhtes Risiko für Harnwegsinfekte. Die Ursache der höheren Prävalenz ist noch nicht nachhaltig geklärt. Bekannt ist, dass Typ-2-Diabetiker erhöhte Konzentrationen freier Fettsäuren im Blut aufweisen. Der veränderte Fettstoffwechsel könnte neben bakteriellen Ursachen ein möglicher Grund für abakterielle Entzündungsreaktionen der Harnblase sein. Zur Prüfung dieser Hypothese wurden zeit- und konzentrationsabhängig kultivierte humane Detrusormyozyten im Vergleich zur Lipopolysaccharid (LPS) induzierten Entzündungsreaktion mit Palmitat stimuliert. Es wurde geprüft, ob eine autokrine und/oder endokrine Regulation des IL-6-Signalwegs vorliegt. Im Fokus standen insbesondere die IL-6- und MCP-1-Expression und deren möglichen regulatorischen Proteine gp80, gp130, NF-κB, STAT3, SOCS3 und MEK1. Die Stimulationsversuche mit LPS und Palmitat zeigen einen differenten zeit- und konzentrationsabhängigen Effekt auf die IL-6- und MCP-1-Expression in den humanen Detrusormyozyten. LPS und Palmitat induzieren eine zeitabhängige autokrine Regulation der IL-6-Signalkaskade über phosphoryliertes STAT3 und Feedback-mechanismen via SOCS3. Sowohl LPS als auch Palmitat bewirken über 48h eine mögliche endokrine Regulation des IL-6-Signalwegs. Zusammenfassend zeigt die Palmitatstimulation zeit- und konzentrationsabhängig einen stärkeren Effekt auf die IL-6-Signalwirkung als die Stimulation mit LPS.:Abkürzungsverzeichnis 1. Hintergrund und Ziel der Arbeit 2. Methoden 3. Ergebnisse 3.1 Struktur und Funktion der suburothelialen Myofibroblasten 3.2 Entzündungsmechanismen der Harnblase 3.3 Einfluss von Palmitat auf die IL-6 and MCP-1 Expression humaner Detrusormyozyten - Link zwischen Stoffwechsel und immunologischer Reaktion der Harnblasenmuskulatur 3.4 IL-6 - JAK/STAT - Signalweg in den Detrusormyozyten 3.5 Schlussfolgerungen 4. Literaturverzeichnis 5. Publikationen 5.1 Struktur und Funktion der suburothelialen Myofibroblasten in der humanen Harnblase unter normalen und pathologischen Bedingungen 5.2 Regulation von Interleukin-6 durch Lipopolysaccharid-Stimulation in kultivierten Detrusormyozyten 5.3 Palmitate induced IL-6 and MCP-1 expression in human bladder smooth muscle cells provides a link between diabetes and urinary tract infections 6. Zusammenfassung der Arbeiten Anlagen / Background: Urinary tract infections (UTI) are more frequent in type-2 diabetes mellitus patients than in subjects with normal glucose metabolism. The mechanisms underlying this higher prevalence of UTI are unknown. However, cytokine levels are altered in diabetic patients and may thus contribute to the development of UTI. Increased levels of free fatty acids (FFA), as observed in obese patients, can induce IL-6 production in various cell types. Therefore we studied the effects of the free fatty acid palmitate and bacterial lipopolysaccharide (LPS) on interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1) expression and secretion in cultured human bladder smooth muscle cells (hBSMC). Methodology/Principal Findings: Biopsies were taken from patients undergoing cystectomy due to bladder cancer. Palmitate or LPS stimulated hBSMC were analysed for the production and secretion of the IL-6, gp80, gp80soluble, gp130, MCP-1, pSTAT3, SOCS3, NF-kB and SHP2 by quantitative PCR, ELISA, Western blotting, and confocal immunofluorescence. In signal transduction inhibition experiments we evaluated the involvement of NF-kB and MEK1 in IL-6 and MCP-1 regulation. Palmitate upregulates IL-6 mRNA expression and secretion via NF-kB dependent pathways in a concentration- and timedependent manner. MCP-1 was moderately upregulated by palmitate but was strongly upregulated by LPS involving NF-kB and MEK1 dependent pathways. Soluble IL-6 receptor (gp80soluble) was downregulated by palmitate and LPS, while membrane-bound gp80 was moderately upregulated. LPS increased SOCS3 and SHP2, whereas palmitate only induced SOCS3. Secondary finding: most of the IL-6 is secreted. Conclusions/Significance: Bacterial infection (LPS) or metabolic alterations (palmitate) have distinct effects on IL-6 expression in hBSMC, (i) short term LPS induced autocrine JAK/STAT signaling and (ii) long-term endocrine regulation of IL-6 by palmitate. Induction of IL-6 in human bladder smooth muscle cells by fatty acids may represent a pathogenetic factor underlying the higher frequency and persistence of urinary tract infections in patients with metabolic diseases.:Abkürzungsverzeichnis 1. Hintergrund und Ziel der Arbeit 2. Methoden 3. Ergebnisse 3.1 Struktur und Funktion der suburothelialen Myofibroblasten 3.2 Entzündungsmechanismen der Harnblase 3.3 Einfluss von Palmitat auf die IL-6 and MCP-1 Expression humaner Detrusormyozyten - Link zwischen Stoffwechsel und immunologischer Reaktion der Harnblasenmuskulatur 3.4 IL-6 - JAK/STAT - Signalweg in den Detrusormyozyten 3.5 Schlussfolgerungen 4. Literaturverzeichnis 5. Publikationen 5.1 Struktur und Funktion der suburothelialen Myofibroblasten in der humanen Harnblase unter normalen und pathologischen Bedingungen 5.2 Regulation von Interleukin-6 durch Lipopolysaccharid-Stimulation in kultivierten Detrusormyozyten 5.3 Palmitate induced IL-6 and MCP-1 expression in human bladder smooth muscle cells provides a link between diabetes and urinary tract infections 6. Zusammenfassung der Arbeiten Anlagen
388

Inflammasome : Investigating the effect of NEK7 in the activation of the NLRP3 Inflammasome

Adindu Uzowuru, Cosmas January 2020 (has links)
Inflammation is a biological defence mechanism applied by living organisms against foreign invaders. In the response to DAMPs and PAMPs, organisms use inflammatory multi-protein complexes to fight the attackers. The most studied inflammasome proteins are NLRP3, ASC and Caspase-1. This study is aimed at understanding the role of NEK7 protein in the NLRP3 inflammasome’s activation, using CRISPR/Cas9 system. To determine the effect of CRISPR/Cas9 and transfection, mRNA expression was analyzed. The results obtained suggest that neither the transfection nor the NEK7 protein knockout have sufficiently worked. This study could not experimentally establish that NEK7 triggers NLRP3 inflammasome activation because ELISA was not conducted to verify the levels of cytokines emitted, due to there being no statistical differences between the samples. Above all, the research question in this thesis project was not answered because the instability of the ACTB reference gene negatively influenced the results. However, previous related studies conclude that NEK7 plays a crucial role in the activation of the NLRP3 inflammasome.
389

Endoplasmic Reticulum Stress and the Unfolded Protein Response Result in Synergistic Upregulation of Interleukin-23 and Interleukin-12 by LPS

Klenk, Erin Ingersoll January 2009 (has links)
No description available.
390

Modifiers for Peri-Implant Mucosal Inflammation during Early Wound Healing

Nguyen, Victoria 30 September 2022 (has links)
No description available.

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