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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.
761

Polimorfismo no gene da interleucina 10 (IL10) em mulheres infectadas pelo papilomavírus humano (HPV)

Tonini, Gabriela January 2009 (has links)
A infecção pelo Papilomavírus Humano (HPV) é um fator associado com o desenvolvimento do câncer de colo de útero. A freqüência de mulheres com infecção genital pelo HPV é consideravelmente mais elevada que o número de mulheres com câncer cervical. Este fato torna relevante a busca de um entendimento maior deste processo, como por exemplo, a predisposição imunológica do hospedeiro. Este estudo tem como objetivo avaliar a freqüência do polimorfismo presente na região promotora (-1082) do gene da IL10 e sua associação com a infecção genital pelo HPV. Trata-se de um estudo de casos e controles, sendo os casos, 84 mulheres com infecção genital por HPV e resultado anatomopatológico alterado. Os controles corresponderam a 211 mulheres HPV-DNA negativas e com exame citopatológico sem alterações. Ambos, casos e controles, são oriundos da população participante de um estudo coorte conduzido previamente. A técnica de amplificação refratária de mutações (ARMS-PCR) foi utilizada para a identificação do polimorfismo presente na região promotora (-1082) do gene da IL10. O cálculo de Equilíbrio de Hardy-Weinberg foi utilizado para verificar se as freqüências genotípicas observadas estão de acordo com as esperadas na população em estudo. O método de Regressão logística múltipla foi utilizado para verificar a associação das variáveis estudadas com o desfecho (infecção genital pelo HPV). A freqüência genotípica observada em mulheres com a infecção foi de 12,0% (AA), 29,0% (AG) e 59,0% (GG). No grupo controle, foi de 22,8% (AA), 48,8% (AG) e 28,4% (GG). Houve diferença significativa entre os grupos estudados (p<0,001). Entre as mulheres com infecção, as lesões de baixo grau (LSIL), predominantes nessa amostra (73,8%), a freqüência do genótipo GG foi 62,9 %. Nos casos com lesões de alto grau (HSIL) (26,2%), o genótipo AG foi observado em 36,4%. Não houve diferença estatisticamente significativa na distribuição dos genótipos em lesões de alto e baixo grau (p=0,59). Além disso, foi observada diferença de significância limítrofe entre a distribuição da freqüência dos genótipos comparando mulheres com HPV oncogênicos em relação a mulheres HPV negativas (p=0,05). Observou-se que o grupo etário (RC=5,00; IC95%:2,33 – 10,75), e o genótipo GG (RC=4,41; IC95%:1,87 – 10,42) apresentaram-se independentemente associados ao desfecho (infecção genital pelo HPV). As variáveis, escolaridade (RC=3,28; 1,00 – 11,18) e coinfecção por HIV (RC=10,64; 1,00-111,11) apresentaram significância limítrofe. Com estes resultados, é possível sugerir que a predisposição determinada geneticamente para a produção de altos níveis de IL10 (GG) parece estar associada à infecção genital pelo HPV, mostrando a importância da resposta imunológica do hospedeiro no processo de infecção e na progressão das lesões cervicais pelo HPV. / Infection with Human Papillomavirus (HPV) is a necessary cause of cervical cancer. The frequency of women infected by HPV is much more elevated than the number of women who develop cervical cancer. Regarding this observation, the search for a better understanding of this process, such as the host immune predisposition, may contribute to its enlightenment. This study aims to evaluate the frequency of the polymorphism in the promoter region (-1082) of the IL10 gene and its association with HPV genital infection. This is a case-control study. A total of 84 cases and 211 controls were enrolled. Cases corresponded to women with HPV genital infection and abnormal histopathological results, and controls were HPV-DNA negatives and with normal cytologic results. The technique of amplification refractory mutation system (ARMS-PCR) was used to identify the polymorphism present at the promoter region (-1082) of the IL10 gen. The Hardy-Weinberg equilibrium was used to verify whether genotypic frequencies were in agreement with the ones expected in the studied population. Multiple logistic regression was used to verify the association between the study factors and the outcome (genital infection by HPV). The genotypic frequency distribution among cases and controls was 12.0% (AA), 29.0% (AG), 59.0% (GG), and 22.0% (AA), 49.0% (AG), 29.0% (GG), respectively. There was a significant difference between the groups (p<0.001). Among the HPV infected women, the low grade lesions (LSIL), predominant in this sample (73.8%) the GG genotype frequency was (62.9%) In those with high grade lesions (HSIL), the AG genotype was observed in (36.4%). No significant association was observed between the genotypes when comparing low and high grade lesions (26.2%). In addition, a borderline significance was observed between the genotype frequency when comparing women infected by a high risk HPV with those HPV-DNA negatives. Age group (OR=5.00; 95%CI: 2.33 – 10.75), and the GG genotype (4.41; 1.87 – 10.42) were independently associated to the outcome (HPV genital infection). The variables schooling (3.28; 1.00 – 11.18) and HIV co-infection (10.64; 1.00- 111.11) presented a borderline significance. The results suggest that a genetic predisposition to produce high levels of IL10 (GG) may be associated to the HPV genital infection, and they indicate the relevance of the host immune response in the development and progression of HPV-related cervical lesions.
762

Avaliação dos polimorfismos nos genes das citocinas IL 6 (RS 1800795) e TGF- &#946; (RS 1982073) e RS 1800471) e suas relações com o grau de lesão cervical em pacientes infectados pelo Papillomavírus humano

Ferreira de Lima Júnior, Sérgio 31 January 2012 (has links)
Made available in DSpace on 2014-06-12T15:02:36Z (GMT). No. of bitstreams: 2 arquivo9594_1.pdf: 387191 bytes, checksum: 6e165c4c1d5b7a1de372a0305283d68c (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2012 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O câncer cervical (CC) é o segundo tipo de câncer mais comum a afetar mulheres em todo mundo. O Papillomavírus humano (HPV) é encontrado em 99% dos casos de CC e a infecção por esse vírus é considerado um fator de risco para o desenvolvimento do câncer. Muitos estudos tem demonstrado uma relação entre polimorfismos nos genes de citocinas e doenças infecciosas. Polimorfismos nos genes da Interleucina-6 (IL-6) e o Fator de Crescimento Transformador (TGF) &#946;1, importantes mediadores do sistema imunológico, tem sido associados com níveis séricos elevados destas citocinas e no desenvolvimento de muitas doenças e tipos de cânceres. O objetivo desse estudo foi verificar se o SNP -174G/C do gene da IL-6 e T869C e G915C do gene do TGF-&#946;1 estão relacionados com o desenvolvimento de Neoplasias Intraepiteliais Cervicais (NIC). 115 amostras de pacientes saudáveis e 115 de pacientes com lesões foram analisadas. As análises dos SNP foram realizadas através do sequenciamento automático de DNA utilizando o MEGABACE 1000 . Os genótipos do polimorfismo -174G/C da IL-6 que possuem pelo menos um alelo C parecem estar envolvidos no desenvolvimento de NIC induzida pelo HPV (p=0.05232). Nenhuma diferença significativa foi encontrada entre as frequências alélicas e genotípicas dos polimorfismos da TGF-&#946;1 nos dois grupos analisados. Além disso, polimorfismos nos genes da IL-6 e TGF-&#946;1 não estão envolvidos na progressão do CIN. Este estudo sugere que o polimorfismo -174G/C do gene da IL-6 pode ser usado como um gene marcador da susceptibilidade a infecção pelo HPV, mas não como um marcador de progressão de NIC na população Pernambucana
763

Il Trovatore e o libreto belcantista / Il Travatore and the belcantist libretto

Aguedo-Silva, Jose Luis 03 December 2009 (has links)
Orientador: Maria Betania Amoroso / Dissertação (mestrado) - Universidade EStadual de Campinas, Instituto de Estudos da Linguagem / Made available in DSpace on 2018-08-13T14:46:52Z (GMT). No. of bitstreams: 1 Aguedo-Silva_JoseLuis_M.pdf: 911871 bytes, checksum: 44097ad9cd9946bce1fdcec2925e4b07 (MD5) Previous issue date: 2009 / Resumo: A ópera sempre teve, desde seus primórdios, uma grande importância para a sociedade, tanto como fonte de lazer como transmissora do pensamento de uma época. E era esta característica que Giuseppe Mazzini (1805-1872), o maior teórico do Risorgimento, considerava primordial: a ópera repassaria a seus ouvintes os ideais risorgimentali. Para isso, era necessário que sobretudo libretistas e compositores estivessem engajados nessa causa. Era o caso de um dos mais representativos libretistas do século XIX, Salvatore Cammarano (1801-1852), prolífico autor, que escreveu libretos para diversos compositores em quase vinte anos de carreira. Dada a sua importância para a História da ópera, enquanto um de seus criadores mais ativos, ele foi escolhido como o objeto principal de nossa pesquisa. Tomamos como objeto de estudo, entre os mais de trinta libretos que Cammarano escreveu, a obra que consideramos a síntese do período: Il Trovatore (1853), ópera em quatro partes com música de Giuseppe Verdi (1813-1901). Il Trovatore nos parece essencial para ir mais a fundo nas pesquisas sobre o Romantismo na Itália. Numa época em que o romance tentava se fixar, a ópera teve uma participação fundamental na divulgação não só dos ideais do Risorgimento, como já citado, mas também na propagação de elementos do movimento romântico, então em voga. Na ópera, o período que coincide com o Romantismo europeu costuma ser chamado Bel Canto tardio, e são consideradas suas datas limite os anos de 1823 (quando da première da Semiramide, de Gioacchino Rossini e Gaetano Rossi) e 1853 (justamente com a Il Trovatore - sendo este mais um motivo para a escolha dessa obra). Dentre os objetivos de nossa pesquisa está o de proporcionar um estudo em português sobre o libreto, uma vez que a literatura relacionada ao assunto é escassa em nossa língua. Além disso, quisemos fazer um panorama da evolução do texto operístico com o passar do tempo, mostrando diferenças e pontos de vista, culminando na última obra de Cammarano, analisada mais profundamente / Abstract: Opera has always had, since its first years, a great importance to society, as a source of leisure and as a transmitter of the thoughts of a time. And the last characteristic is the one which Giuseppe Mazzini (1805-1872), the most important theorist of Risorgimento, considered essential: opera would be able to pass to its listeners the risorgimentali ideals. In order to do that, it was necessary that librettists and composers were engaged in this cause. That was the case of one the most representatives librettists of the 19th century, Salvatore Cammarano (1801-1852), prolific author, who wrote librettos for several composers in almost twenty years of a career. Given his importance to opera history, as one of its most active creators, he was chosen as the main object of our research. We chose to study, among more than thirty librettos written by Cammarano, the work that we consider the synthesis of the period: Il Trovatore (1853), opera in four parts set to music by Giuseppe Verdi (1813-1901). Il Trovatore seems essential to us in order to go further in our understanding of Italian Romanticism. In a time when the novel tried to fix itself, opera had a fundamental participation in spreading not only the risorgimentali ideals, as already said, but also the Romantic elements present in the age. In opera, the period which coincides with the European Romanticism is usually called late Bel Canto, and its limit dates are 1823 (when Semiramide, by Gioacchino Rossini and Gaetano Rossi was premièred ) and 1853 (with Il Trovatore). Among the objectives of our research is to provide a study in Portuguese about libretto, since the literature related to this subject is scarce in our language. Besides, we wanted to make an overview of the evolution of operatic text over time, showing differences and points of view, culminating in the last work of Cammarano, which we analyzed more profoundly / Mestrado / Literatura e Outras Produções Culturais / Mestre em Teoria e História Literária
764

Avaliação da participação de citocinas (interleucina 32, interleucina 10, fator de necrose tumoral) e receptores similares a Toll (TLR 4) na infecção por Leishmania (Viannia) sp. / Evaluation of the participation of cytokines (interleukin-32, interleukin-10, tumor necrosis factor) and Toll-Like receptors (TLR 4) in infection by Leishmania (V.) sp.

Galdino Júnior, Hélio 26 July 2013 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2016-08-17T20:24:56Z No. of bitstreams: 2 Tese - Hélio Galdino Júnior - 2013.pdf: 3450540 bytes, checksum: 01adc52cca765449b5eed357351fb5ee (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-18T12:50:37Z (GMT) No. of bitstreams: 2 Tese - Hélio Galdino Júnior - 2013.pdf: 3450540 bytes, checksum: 01adc52cca765449b5eed357351fb5ee (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-18T12:50:37Z (GMT). No. of bitstreams: 2 Tese - Hélio Galdino Júnior - 2013.pdf: 3450540 bytes, checksum: 01adc52cca765449b5eed357351fb5ee (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2013-07-26 / American Tegumentary Leishmaniasis (ATL) is a disease caused by protozoa Leishmania. In Brazil, the most prevalent species is L. (Viannia) braziliensis. Several cytokines and receptors are involved in immunopathogenesis of ATL, however, the role of interleukin 32 (IL-32) was not investigated in this disease. Besides, toll-like receptors (TLR) were poorly evaluated in Leishmania infection, especially when it is caused by L. (V.) braziliensis. The aim of the present study was to evaluate IL-32, TNF and IL-10 expression in ATL lesions; the induction of IL-32 by L. (V.) braziliensis amastigotes in human peripheral blood mononuclear cells (PBMC) cultures as well as the involvement of TLR4 in monocyte/macrophage response to L. (V.) brazilienis amastigotes. Biopsies fragments from cutaneous and mucosal lesion and healthy tissues were used to investigate the subgenus of the parasites by PCR-RFLP assay; expression of IL-32, TNF and IL-10 was assayed by immunohistochemistry and expression of IL-32 isoforms     , TNF and IL-10 was analysed by qRT-PCR. The PBMC were cultured with L. (V.) braziliensis amastigotes in the absence or presence of IFN and IL-32 induction was assayed by qRT-PCR; and TNF and IL-10, by ELISA. TLR4 was neutralized by monoclonal antibodies and lipopolysaccharide (LPS) was used as TLR4 agonist. The expression of TLR4 in monocyte/macrophages was evaluated by flow cytometry. Thirty five patients were evaluated, 23 with cutaneous leishmaniasis (CL) and 12 with mucosal leihsmaniasis (ML). All parasite positive samples contained L. (Viannia) sp. The expression of IL-32 (protein and mRNA) was similar in CL and ML lesions but was higher than in health tissues. Only IL-32 was detected. The proteins TNF and IL-10 were detected in similar levels in CL and ML lesions, but TNF mRNA was present in higher levels in ML (4.069x) than in CL lesions (141 x, p < 0.05). L. (V.) braziliensis amastigotes induced IL-32, TNF and IL-10 in IFN pre-treated PBMC. The production of TNF and IL-10 was TLR4 dependent and treatment of PBMC with LPS further increased the production of TNF induced by amastigotes (p < 0.05). However, LPS did not altere the IL-10 production. Treatment with IFN enhanced the percentage of TLR4+ monocyte/macrophage (p < 0.05), which was decreased following incubation with amastigotes (p = 0.06). The results showed that IL-32 is produced during L. (Viannia) infection and TLR4 mediates L. (V.) braziliensis amastigote-induced TNF and IL-10 production in human PBMC. Moreover, the data suggest that amastigotes can lead to TLR4 internalization what can allow parasite to evade of innate immune response. This study indicates that IL-32 and TLR4 are important players in human infection caused by L. (Viannia), especially L. (V.) braziliensis. Whether TLR4 is also important to IL-32 production by human monocytes/macrophages deserves further investigation. / A leishmaniose Tegumentar Americana (LTA) é uma doença infecto-parasitária, causada, no Brasil, principalmente pela espécie Leishmania (Viannia) braziliensis. Na imunopatogenia da LTA participam várias citocinas e receptores. A interleucina 32 (IL-32) é uma citocina pro-inflamatória, cuja participação na LTA ainda não foi investigada. O papel dos receptores similares a Toll (TLR) na LTA tem sido pouco investigado, especialmente considerando infecção por L. (V.) braziliensis. O objetivo deste estudo foi avaliar a expressão da IL-32, do TNF e da IL-10 nas lesões de pacientes com LTA, a indução de IL-32 por formas amastigotas de L. (V.) braziliensis em células mononucleares (CMN) humanas, bem como avaliar a participação do TLR4 na infecção de monócitos/macrófagos humanos com formas amastigotas de L. (V.) brazilienis. Fragmentos de lesões cutâneas ou mucosas de pacientes com LTA e tecidos sadios foram obtidos, sendo usados para a determinação do subgênero de Leishmania, usando a PCR-RFLP; para análise de IL-32, TNF e IL-10 por imunoistoquímica; e para análise da expressão das isoformas     da IL-32, do TNF e da IL-10, por qRT-PCR. As CMN foram cultivadas com amastigotas de L. (V.) braziliensis, na ausência ou presença de IFN e a indução de IL-32 foi avaliada por qRT-PCR e TNF e IL-10, por ELISA. Para neutralização de TLR4 foram usados anticorpos monoclonais e lipopolissacarídeo (LPS), como agonista de TLR4. A expressão de TLR4 nos monócitos/macrófagos presentes nas CMN foi avaliada por citometria de fluxo. Foram analisados 35 pacientes sendo 23 leishmaniose cutânea (LC) e 12 com leishmaniose mucosa (LM). Todas as amostras PCR positivas continham parasitos pertencentes ao subgênero Viannia. Nas lesões de pacientes com LC e LM foi detectada uma maior expressão tanto da proteína quanto do mRNA da IL-32 do que nos tecidos controles, porém níveis similares foram encontrados nas duas formas clínicas. Somente a isoforma IL-32 foi detectada. As proteínas TNF e a IL-10 foram detectadas nas lesões, em níveis similares na LC e na LM, porém, o mRNA do TNF estava em níveis mais elevados nas lesões de LM (4.069 vezes) do que nas lesões de LC (141 vezes, p < 0,05). As formas amastigotas de L. (V.) braziliensis indiziram a produção de IL-32 TNF e de IL-10 nas CMN pré-tratadas com IFN. A produção de TNF e IL-10 foi dependente de TLR4 e o tratamento das CMN com LPS aumentou a produção do TNF induzido pelas amastigotas (p < 0,05), mas não alterou a produção da IL-10. A incubação com IFN aumentou significantemente a porcentagem de monócitos/macrófagos TLR4+ (p < 0,05), a qual foi diminuída pelas formas amastigotas (p = 0,06). Os resultados mostram que a IL-32 é produzida durante a infecção humana causada por L. (Viannia) e evidenciam a participação de TLR4 na indução de TNF e IL-10 em CMN humanas por formas amastigotas de L. (V.) braziliensis. Ainda, os dados sugerem que as formas amastigotas causam a internalização dos TLR4, o que pode ser um mecanismo de evasão da resposta imune. Portanto, a IL-32 e o TLR4 parecem importantes componentes na infecção humana causada por L. (Viannia), especialmente L. (V.) braziliensis, podendo contribuir para a imunopatogenia ou para o controle da infecção.
765

Kan träning vara ett alternativ till läkemedel vid låggradig systemisk inflammation?

Johansson, Malin January 2014 (has links)
Introduktion: Inflammation är en bidragande orsak till flera av dagens folksjukdomar t ex diabetes, ateroskleros, neurodegenerativa sjukdomar och vissa former av cancer. Inflammation karaktäriseras av en 2-4 gånger förhöjd nivå av anti- och proinflammatoriska cytokiner (framför allt IL-6 och TNF-a) samt ökad halt C-reaktivt protein. Idag behandlas inflammation i första hand med NSAID-preparat. Då träning frisätter antiinflammatoriska cytokiner är syftet med detta arbete att undersöka om det finns vetenskapliga bevis för att träning skulle kunna vara en behandlingsmetod vid låggradig systemisk inflammation. Metod: Studien har genomförts genom att studera och utvärdera vetenskapliga artiklar inom området, framför allt översiktsartiklar och kliniska studier, vilka har erhållits genom sökning i vetenskapliga databaser. Resultat: Resultaten från studierna som mäter den antiinflammatoriska effekten av träning pekar på att träning minskar halten av TNF-a och CRP samt ökar halten av IL-6. NSAID verkar sänka nivån TNF-a, IL-6 och CRP. Vid inflammatoriska tillstånd ses en förhöjd halt IL-6, som produceras från T-celler och makrofager och som effekt av ökande halt TNF-a. I samband med träning ses en ökning av IL-6 från den kontraherande muskeln. IL-6 från muskler verkar ge såväl en metabolisk som en antiinflammatorisk effekt genom att påverka lipidmetabolismen respektive minska utsöndringen av TNF-a. Slutsats: Träning höjer halten IL-6, vilket även leder till en hämning av TNF-a. Den här studien kan dock inte avgöra om NSAID eller träning har bäst effekt för att minska systemisk låggradig inflammation.
766

Analyses post-génomiques : étude de l'implication d'IL-33 et de BIN1 dans la physiopathologie de la maladie d'Alzheimer / Post-genomic analyses : study of IL-33 and BIN1 involvement in Alzheimer's disease physiopathology

Mounier, Anaïs 14 March 2013 (has links)
Les analyses génomiques ont permis d’identifier des gènes et des protéinesimpliqués dans la maladie d’Alzheimer (MA). Au laboratoire, des approchesdifférentes ont mis en évidence deux gènes différentiellement exprimés dans lamaladie : le gène IL-33, retrouvé comme étant sous-exprimé chez les patientsatteints de MA, et le gène BIN1, identifié par des approches de GWAS et retrouvécomme étant sur-exprimés dans le cerveau des patients.Nous avons observé que la protéine IL-33 avait un impact sur le métabolismedu précurseur du peptide amyloïde (APP) de par sa fonction de facteur de régulationtranscriptionnelle. Nous avons alors cherché à identifier les gènes modulés par IL-33ainsi que des sites potentiels de fixation de la protéine sur l’ADN par des analyses àhaut débit. Il a été observé qu’IL-33 avait une forte implication dans la transcriptiondes gènes et pouvait agir directement sur l’ADN de par son impact sur les histones.De plus, IL-33 augmenterait l’expression de la préséniline 2, ce qui expliquerait alorsson impact sur le métabolisme de l’APP.Nous avons identifié un polymorphisme fonctionnel dans la région régulatricedu gène BIN1 associé à la maladie et pouvant expliquer la variation de sonexpression retrouvée dans le cerveau des patients. Nous avons également retrouvéune interaction de la protéine BIN1 avec Tau. BIN1 est alors le premier déterminantgénétique de la MA retrouvé comme étant associé à Tau et pourrait expliquer le lienentre la pathologie amyloïde et la pathologie Tau.Nos analyses nous ont donc permis, à partir des résultats d’analysesgénomiques, de mieux comprendre les mécanismes impliqués dans laphysiopathologie de la MA. / Genomic analyses allowed to identify genes and proteins involved inAlzheimer’s Disease (AD). In the laboratory, genetic and transcriptomic approachesrevealed two genes differentially expressed in AD: IL-33 gene, found to be underexpressedin AD cases brain, and BIN1 gene, found by GWAS analyses and overexpressedin brains of AD cases.As regards to IL-33, we observed that this protein have an impact on amyloidprecursor protein (APP) metabolism by its transcriptional regulation properties. So,we tried to identify the genes modulated by IL-33 using transcriptomic high-troughputanalyses and we identified IL-33 DNA binding sites by ChIP-on-chip approaches. Weobserved that IL-33 was involved in gene transcription and could act directly on DNAby interaction with histones. We also observed that IL-33 increase the expression ofpresenilin 2, which can explain its effect on APP metabolism.As regards to BIN1, we identified one functional polymorphism in regulatoryregion of this gene associated with AD and allowed to explain the expressionvariation of BIN1 in AD brains. We also found an interaction of BIN1 with Tau. So,BIN1 would be the first genetic risk factor for AD linked to the “Tau pathway” andcould explain the link between amyloid pathology and Tau pathology.The analyses performed in the laboratory allowed to, from genomic analysesresults, a better understanding of mechanisms involved in AD physiopathology.
767

MAST CELL ACTIVATION BY DIVERSE STIMULI CAN BE SUPPRESSED BY STEROID THERAPY AND TARGETING THE FYN-STAT5B CASCADE

Paranjape, Anuya 01 January 2017 (has links)
Mast cells are critical effectors of allergic disease that can be activated by numerous stimuli. We have examined mast cell control by the inflammatory cytokine, IL-33, as well as IgG. In the first study reported here, we found that the synthetic glucocorticoid, dexamethasone, potently and rapidly suppressed IL-33-induced cytokine production from murine bone marrow–derived and peritoneal mast cells, as well as human mast cells. Dexamethasone also antagonized IL-33-mediated enhancement of IgE-induced cytokine production and migration. Although dexamethasone had no effect on IL-33-induced phosphorylation of MAP kinases or NFκB p65 subunit, it antagonized AP-1 and NFκB-mediated transcriptional activity. Finally, intraperitoneal administration of dexamethasone completely abrogated IL-33-mediated peritoneal neutrophil recruitment and prevented plasma IL-6 elevation. These data demonstrate that steroid therapy may be an effective means of antagonizing the effects of IL-33 on mast cells in vitro and in vivo, acting partly by suppressing IL-33-induced NFκB and AP-1 activity. In the second study reported here, we found that Fcγ receptor crosslinkage activated the transcription factor Stat5B through a Fyn kinase-dependent pathway. We then showed that STAT5B is critical for IgG-induced cytokine production by mast cells but not macrophages. To expand these studies, we employed the K/BxN model of inflammatory arthritis, which has roles for mast cells and macrophages. In this model, Fyn or STAT5B deficiency only affected the arthritic flare that primarily depends on mast cell degranulation, without affecting the severity of the joint swelling. By contrast, Lyn kinase deficiency significantly exacerbated arthritis. These studies indicate a clinically relevant, lineage-restricted role for the Lyn/Fyn-STAT5 cascade. Collectively, our work demonstrates that mast cell activation by diverse stimuli can be suppressed by steroid intervention and selectively targeted by disrupting kinase-transcription factor pathways.
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Die Funktion von CX3CR1 in einem spontanen Modell der experimentellen Autoimmunenzephalomyelitis / The function of CX3CR1 in a spontaneous model of experimental autoimmune encephalomyelitis

Hollasch, Heiko 18 October 2016 (has links)
Die Multiple Sklerose (MS) ist eine entzündliche Autoimmunerkrankung des Zentralnervensystems. Die klinisch und pathologisch heterogene Erkrankung wird im Tiermodell am besten durch eine experimentelle Autoimmunenzephalomyelitis (EAE) abgebildet. Entzündliche Läsionen einer EAE sind neben Lymphozyten durch Monozyten/ Makrophagen gekennzeichnet. Der in dieser Arbeit untersuchte Chemokinrezeptor CX3CR1 findet sich auf murinen Monozyten des Blutes und wird dort unterschiedlich hoch exprimiert. Im ZNS werden der Rezeptor auf Mikroglia und der Ligand Fraktalkin (CX3CL1) konstitutiv und somit entzündungsunabhängig auf Neuronen exprimiert. In verschiedenen Tiermodellen neurologischer Erkrankungen wurden unterschiedliche Auswirkungen dieser Interaktion beschrieben. Die vorliegende Studie untersucht die Fragestellung, ob sich in einem spontanen EAE-Modell CX3CR1-defiziente OSE-Mäuse von CX3CR1-kompetenten OSEMäusen hinsichtlich spontaner EAE-Inzidenz, Erkrankungsverlauf und Läsionspathologie unterscheiden. CX3CR1-defiziente OSE-Mäuse zeigen in diesem Modell eine erhöhte Inzidenz (54% vs. 32%), aber einen milderen Krankheitsverlauf gegenüber Rezeptor-Wildtypen. Dem milderen Krankheitsverlauf entsprechend weisen OSE CX3CR1-defiziente Mäuse histopathologisch in der akuten Phase kleinere demyelinisierte Läsionen der spinalen weißen Substanz und geringere meningeale spinale entzündliche Infiltrate auf mit einer signifikant geringeren Makrophageninfiltration in den Läsionen. In der spinalen grauen Substanz zeigen sie eine mildere neuronale Schädigung. In der chronischen Krankheitsphase findet sich eine reduzierte Infiltration von Entzündungszellen ohne signifikanten Unterschied zwischen OSE CX3CR1-defizienten Mäusen und Rezeptorwildtypen. Molekularbiologisch zeigen OSE CX3CR1-defiziente Mäuse eine verstärkte Expression von IL-17a in der akuten Krankheitsphase. Die erhöhte EAE-Inzidenz in CX3CR1-defizienten OSE-Mäusen ist am ehesten auf ein vermehrte Generierung von enzephalitogenen 2D2 T-Zellen im Darm in diesem spontanen EAE-Modell zurückzuführen. Der mildere Krankheitsverlauf bei CX3CR1- defizienten Mäusen weist auf eine Bedeutung von CX3CR1 in der Migration von Monozyten in das entzündete ZNS hin. Die vorliegende Arbeit ist die Grundlage für weiterführende Studien, in welchen die Bedeutung der Fraktalkin-CX3CR1-Interaktion für kortikale Pathologie bei der EAE untersucht werden wird.
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Towards the analyses of cell lineages using conditional gene alterations

Costello, Ryan January 2016 (has links)
The ability to precisely modify the mouse genome is an invaluable tool for any researcher. If an artificial epitope sequence is integrated into target loci in specific cell types, it is possible to generate mice with these cells specifically tagged with the epitope, which can be used for many subsequent studies. Homologous recombination and the Cre/loxP system have been used to generate targeted and conditional transgenic mice, which have provided the basis for many studies into gene function. However, in recent years, improvements in technology have led to the development of RNA and protein based methods of specifically editing DNA sequences at user-selected loci. This thesis aimed to investigate the effectiveness of the novel gene targeting methods TALEN and CRISPR/Cas9. It also aimed to utilize different strains of mice generated using the Cre/loxP system in Trichuris muris, an animal infection model of the human disease Trichuris trichiura. TALENs use a pair of protein-based monomers specific to the sense and anti-sense strand of a target DNA sequence to dimerise a FokI nuclease and initiate a deletion in the genome. As a study into the practical use of this emerging technology TALENs were generated to target Oct-4 (a stem cell marker) in order to integrate an artificial epitope sequence, which could be used for enrichment experiments. The CRISPR/Cas9 is a very efficient RNA-based system used for modifying a target sequence. This system has been utilized to integrate an epitope sequence into the Rosa26 locus, downstream of a floxed STOP codon. This allows for expression of the epitope following the introduction of tissue restricted Cre recombinase. IL-1 is an important cytokine in the immune response towards T.muris. IL-1R1 was conditionally removed in CD4 cells and the role of IL-1 signaling in developing Th1, Th2 and Th17 responses was then studied. Interestingly, IL-1R1fl/fl CD4Cre mice could generate Th1 and Th2 response but showed a reduction in IL-22 and IL-17 production, two key Th17 cytokines. Infected IL-1R1fl/fl CD4Cre mice also displayed increased gut morphology and goblet cell hyperplasia. Therefore, it was concluded that IL-1 signaling from CD4 cells has an important role in host defense and the development of a full Th17 response. It was also shown that removing IL-1R1 in naïve mice had no affect on lymphocyte development. IL-10 is an anti-inflammatory cytokine expressed by gut macrophages, which contributes to homeostatic control of the immune system. IL-10R was specifically removed in the macrophage specific Cre lines LysMCre and also in CX3CR1Cre as a way of comparing the two Cre drivers. The mice were then infected with T.muris and displayed significant inflammation and also failure to expel the worms in the LysMCre model. This suggests a role for this model in future studies of gut macrophages. Clearly, animal models are very important in the study of gene function and also as a method of assessing the application of new technologies such as CRISPR/Cas9. Future work with the artificial epitope specifically targeted into important cell lines will form the basis of many important studies directly applicable to human disorders. As the technologies improve, the scope for developing therapeutics increases and genetic modification has an immeasurable role to play.
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α-subunit dependent regulation of GlyR function and dynamics by IL-1β and PKA in spinal cord neurons / La régulation de GlyR dépend de la sous-unité alpha fonction et dynamique de IL-1β et PKA dans les neurones de la moelle épinière

Patrizio, Angela 23 September 2016 (has links)
Différentes études précédentes ont démontré que IL-1β et PKA peuvent réduire la transmission synaptique inhibitrice dans la LAMINA II de la moelle épinière, en contribuent de cette manière au développement de douleur chronique de tipe inflammatoire. Au niveau des sites post-synaptiques, les changements dans la transmission synaptique (par exemple suivant le relâchement de IL-1β ou après l’activation de PKA), reflètent donc des changements dans les propriétés et/ou dans le nombre des molécules présentes au niveau de la synapse. Au cours de mon doctorat, j’ai pu profiter des techniques basés sur l’imagerie des molécules uniques afin d’étudier les effets de PKA et IL-1β sur la dynamiques et le nombre absolu de GlyR dans les synapses de la moelle épinière. Mes résultats ont montré que PKA et Il-1β peuvent déplacer les GlyR des sites inhibitoires post-synaptiques ciblent différentes sous-unités α du récepteur de la glycine. Comme les sous-unités GlyRα ne se lient pas directement à la géphyrine, ces effets sont vraisemblablement le résultat d’un changement de conformation du GlyR dépendant de la sous-unité. Pendant mon projet, j’ai utilisé la technique de microscopie de super-résolution PALM pour développer une méthode pour déterminer la stœchiométrie des GlyR et le nombre absolu de récepteurs et des molécules d’échafaudage au niveau des synapse de la moelle épinière. Mes résultats décrivent que les GlyR se composent de 3 sous-unités α et de 2 sous-unités β, et proposent qu’une synapse de la moelle épinière contient en moyenne 80 GlyR et 250 molécules de géphyrine. Ces résultats sont essentiels pour mettre en relation l’ampleur des mécanismes de régulation et de plasticité agissant sur la transmission synaptique, avec les changements en nombre de molécules présentes dans les synapses de la moelle épinière. Sur la base de mes découvertes on pourra maintenant étudier les mécanismes structuraux impliqués dans la régulation de la fonction et la dynamique des GlyR dépendantes des sous-unités α que j’ai démontré. / IL-1β and PKA impair glycine receptor-mediated synaptic transmission in the lamina II of the spinal cord, contributing to the development of inflammatory types of chronic pain. At post-synaptic sites, the strength of synaptic transmission depends on the biophysical properties and on the absolute number of receptors expressed. Consequently, changes in synaptic transmission (i.e. following the release of IL-1β or the activation of PKA), reflect changes in the properties and/or number of molecules present at the synapse. During my PhD I have taken advantage of single-molecule based imaging techniques to study the effects of IL-1β and PKA on the dynamics and absolute numbers of GlyRs at spinal cord synapses.My results show for the first time that both Il-1β and PKA displace GlyRs from inhibitory post-synaptic sites, targeting different α-subunit of GlyRs. Specifically, IL-1β reduces GlyR α-containing receptors at spinal cord synapse, whereas PKA affects GlyR α3L subunit. Given that the GlyR α subunits do not bind to the gephyrin scaffold, these effects likely reflect an α-subunit dependent change in GlyR conformation that decreases the affinity of the GlyR subunits for gephryrin. Glycine receptors are composed of α- and β- subunits that assemble into heteropentameric complexes with an unclear stoichiometry. Using super resolution PALM microscopy I have developed a single-molecule counting approach to determine the stoichiometry of GlyRs and the absolute number of receptor and scaffold molecules at spinal cord synapses. According to my results GlyRs is composed by 3 α and 2 β-subunits, and an average spinal cord synapse contains around 80 GlyRs and 250 scaffold molecules. These data are fundamental to relate the magnitude of regulatory and plasticity mechanisms acting on glycinergic transmission, with quantitative changes in molecule numbers at spinal cord synapses. My research has shown how absolute quantitative approaches can help achieve a more detailed insight into the organization of complex molecular assemblies and their dynamic regulation.

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