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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.
71

Potential Roles for the Neurotrophic Molecules Agrin and Neuregulin in Regulating Aspects of the Inflammatory Response

Mencel, Malwina 22 May 2015 (has links)
Agrin and neuregulin are neurotrophic molecules well known for their roles at synapses in the peripheral and central nervous systems. The expression of these two molecules is not restricted to these sites however, as they are broadly expressed across multiple organ systems. What roles do agrin and neuregulin play within these alternate systems; what is the function of these molecules outside the nervous system? Here I investigate potential roles for agrin and neuregulin in inflammation. Inflammation is an immediate response by innate immune cells, primarily macrophages, to infection and is characterized by the synthesis of pro-inflammatory mediators. The innate immune system possesses multiple redundant mechanisms to locally control inflammation. The neuro-immune axis is one means of control. Often called the cholinergic anti-inflammatory pathway, it acts to regulate local inflammation via nerve-secreted acetylcholine signaling through the homopentameric α7 nicotinic acetylcholine receptors (α7nAChR) present on macrophages. Both agrin and neuregulin have been independently described to share an intricate relationship with acetylcholine receptors (AChR) in the nervous system. Agrin is best known for its role in AChR aggregation at the neuromuscular junction while neuregulin has related roles in AChR transcription, cell survival, communication and differentiation. Based on the common characteristics of synapses in the nervous and immune systems we were curious to see if agrin and neuregulin played analogous roles on macrophages. Here we show that agrin and its receptor dystroglycan are expressed on RAW264.7 macrophages. In addition, agrin treated macrophages demonstrate increased endogenous agrin and α7nAChR expression. By blocking α-dystroglycan (α-DG), a receptor for agrin, with an anti-α-DG antibody we further saw a reduction in agrin expression. We also show that agrin is able to aggregate surface α7nAChRs and transmembrane agrin co-localizes with α7nAChRs therein. Agrin appears to induce approximately a 15-fold increase in anti-inflammatory cytokine IL-10 in macrophages but does not increase pro-inflammatory cytokine TNF-α or IL-6 synthesis. Agrin-treated macrophages challenged with LPS, a potent activator of inflammation, exhibit a 57% decrease in IL-6. Macrophages treated with agrin also exhibit a 4-fold increase in STAT3, a regulator of anti-inflammatory action. The potential anti-inflammatory effects of agrin in the periphery parallel previous work describing the effects of neuregulin in the brain. Previous work completed by our lab suggests a role for neuregulin in augmenting the expression of α7nAChRs on microglia, the macrophages of the brain, but not in peripheral macrophages. Here we show that treatment of LPS challenged microglia with neuregulin produces an 88% decrease in IL-6 and a 33% decrease in TNF-α. These results indicate both agrin and neuregulin are able to induce an increase in α7nAChRs and augment the synthesis of pro- and anti-inflammatory cytokines in their respective systems. These results also further the support the evidence of neuro-immune crosstalk in the immune system. Taken together these results present two novel players in inflammatory regulation by macrophages in the periphery and CNS.
72

Mucositis Prevention for Patients Receiving High Dose Chemotherapy and Stem Cell Transplantation : Preventive Strategies - There is Always More to do

Svanberg, Anncarin January 2012 (has links)
The aim of this thesis was to investigate oral cryotherapy (OC) as prophy-laxis against oral mucositis (OM) in patients given high-dose chemotherapy for stem cell transplantation (SCT). A new mouth rinse device was tested for possible additive effect to OC. For study I-III, 78 patients were randomised to OC or standard oral care (SOC). Papers I and II showed that OC patients had significantly less severe mucositis, pain, opioid use, lower C-reactive protein and less parenteral nutrition treatment (TPN). There was no difference in relapse rate, and 5-year survival was unexpectedly significantly better in the OC group (Paper III). In paper IV, the local effect of OC on the mucosa of the mouth was investigated by the use of an infrared thermograph. Change in surface temperature in eight areas of the mouth cavity was measured after cooling of the mouth in healthy volunteers. A substantial lowering of the temperature (-12.9 °C, mean) was seen which could explain the efficacy of OC. To exclude that acute cooling in itself is traumatic, the proinflammatory cytokine IL-6 was measured in saliva and showed no increase after cooling. Paper V reported a study in 40 allogeneic SCT patients. 20 were given SOC including OC and 20 in addition received Caphosol®, a calcium phosphate mouth rinse, during chemotherapy and until day 21. Severity of mucositis, use of opioids and TPN, effects on nutrition and CRP levels were measured. No significant difference was found between the groups in any of these variables, but a non-significant trend for an advantage for the combination could be seen. IL-6 saliva levels were measured. There was a substantial increase (more than 10-fold), in mean IL-6 levels from baseline to beginning of mucositis and a weak correlation between increased IL-6 levels and severity of OM, suggesting that IL-6 in saliva may be a useful marker of the inflammatory mucosal process. This thesis demonstrates that OC is effective as prophylaxis against chemotherapy-induced OM. As a consequence of this work, OC has been introduced as the standard of care in all SCT patients in our institution.
73

Characterisation of blood myeloid dendritic cells in mannose binding lectin-sufficient and mannose binding lectin-deficient individuals

Melinda Dean Unknown Date (has links)
Mannose binding lectin (MBL) belongs to the collectin family of soluble pattern recognition molecules that elicit diverse biologic activities. Via multiple carbohydrate-recognition domains (CRD), MBL binds to mannose and N-acetyl-glucosamine oligosaccharides present on the surface of bacteria, fungi and yeast. Following pathogen recognition, MBL activates the complement system via MBL associated serine proteases in a manner independent of antibody and C1 complex. Deficiency in function and level of MBL is found in 25% of otherwise apparently healthy individuals, representing the most prevalent innate immune deficiency. MBL deficiency is a risk factor for the development of infections in humans and mice. The role of MBL as a modulator of infection is complex. MBL deficiency may influence proinflammatory cytokine production, expression of leukocyte adhesion molecules, or vascular damage, during the course of infection. Given that dendritic cells (DC) are antigen presenting cells (APC) with potent capacity to respond to microbial stimulation, I hypothesized that MBL deficiency may be reflected in DC functions associated with microbial stimulation. Initially, I investigated the association of MBL with human immune cells and demonstrated that in both MBL-Sufficient (MBL-S) and MBL-Deficient (MBL-D) individuals, MBL was particularly associated with monocytes. RT-PCR analysis demonstrated MBL was not transcribed by monocytes or other immune cells investigated (T, B, and NK cells, CD11c+DC, immature monocyte derived DC [MoDC], LPS matured MoDC, and granulocytes), suggesting MBL association with the cell surface may be via an adapter or co-receptor. Magnetically separated monocytes but not MoDC bound exogenous purified human plasma MBL (hpMBL). Addition of hpMBL (5 -15 µg/mL) did not induce MoDC activation, and MBL added together with lipopolysaccharide (LPS) did not induce MoDC activation above the level induced by LPS only. In the second part of this study, I used the particulate MBL ligand zymosan (Zy) as a pathogenic stimulus in a whole blood model to gain a greater understanding of the consequences of MBL deficiency. I compared surface phenotype, inflammatory cytokine production and antigen presenting capacity of blood myeloid (M)DC of MBL-D and MBL-S individuals following stimulation with Zy and MBL opsonised Zy (MBL-Zy). Blood MDC in MBL-D individuals, unlike their counterpart in MBL-S individuals, displayed unique functional characteristics, including higher production of proinflammatory cytokines IL-6 and TNF-, but poor capacity for allo-T cell effector cell induction. It appeared that stimulation with MBL-Zy reduced elevated production of IL-6 but not TNF- by blood MDC in MBL-D individuals. In the third part, expression microarray analysis was utilised to provide broad information on the genes and potential signalling pathways involved in the MDC responses in MBL-D and MBL-S individuals following stimulation with Zy and MBL-Zy. MBL-S individuals demonstrated greater capacity to induce T cell and NK cell signalling pathways than MBL-D individuals. Further, MBL acted as a regulator of important inflammatory molecules, namely T-cell receptor zeta (CD247), IFN-γ and perforin 1. The data presented in this study provides novel information on blood MDC function in MBL-S and MBL-D individuals in response to pathogen stimulation, and provided insight into mechanisms involved in the increased frequency of infection observed in MBL-D individuals.
74

Role of the Histamine Releasing Factor (HRF) in Plasmodium parasite transmission and disease pathogenesis / Rôle de la protéine Histamine Releasing Factor (HRF) dans la transmission du parasite Plasmodium et dans le développement de la pathogénèse de la maladie

Demarta-Gatsi, Claudia 22 November 2016 (has links)
De études récentes suggèrent une forte relation entre susceptibilité au paludisme et réponse allergique. Des niveaux élevés d’histamine plasmatique et tissulaire ont été associés à la sévérité de la maladie chez l’homme infecté par P. falciparum et dans de nombreux modèles animaux. Histamine releasing factor (HRF), une protéine pro-inflammatoire libérant l'histamine au cours des processus allergiques, est produite par le parasite au cours des infections palustres modérées et sévères, suggérant l’implication du HRF dans l’altération des réponses immunitaires et dans la pathogenèse. Les objectifs de ce travail consistaient à évaluer le rôle de la protéine parasitaire HRF dans le développement de la réponse immunitaire et à déterminer si son expression est associée à la sévérité de la maladie en étudiant deux parasites murins, PbANKA et PbNK65, déficients pour la protéine HRF (hrfΔ). Les souris infectées avec des sporozoïtes PbANKA-hrfΔ ont montré une diminution de la fréquence du neuropaludisme associée à un déficit du développement des parasites mutants au cours du stade hépatique et à une augmentation précoce systémique d’IL-6. En outre, l'infection par les parasites PbNK65-hrfΔ est caractérisée par l’élimination du parasite conduisant à une protection durable et au développement d’une mémoire immunitaire caractérisée par une augmentation d’IL-6, une diminution de l’expression de PD-1 sur les cellules T et une amélioration de la phagocytose dépendante des anticorps, confirmant l'importance de la protéine HRF dans la virulence du parasite. HRF est le premier gène de parasite Plasmodium dont l’effet direct sur la réponse immunitaire de l’hôte est démontré. / Recent findings have raised the hypothesis that clinical susceptibility to malaria may be related to allergy-type response. In human infection with P. falciparum, as well as in murine models of malaria, increased levels of histamine have been shown to be associated with disease severity. Histamine releasing factor (HRF), shown to be implicated in the release of pro-inflammatory histamine during late-phase allergy, was demonstrated to be produced by the parasite during mild and severe malaria infections suggesting that Plasmodium HRF may affect host immune responses and contributes to the pathogenesis. The objectives of this work were to evaluate the role of Plasmodium HRF in the development of the immune response and to determine whether its expression is associated with the severity of malaria disease by studying two HRF-deficient (hrfΔ) murine parasites (PbANKA and PbNK65). Infection with PbANKA-hrfΔ sporozoites showed a decrease in the frequency of ECM due to the impairment of the development of the mutant parasites in liver stages as a consequence of the up-regulation of IL-6. Infection with PbNK65-hrfΔ parasites confirmed the importance of HRF in enhancing the virulence of the parasite. Indeed, PbNK65-hrfΔ infection results in parasite clearance leading to a long-lasting protection and immune memory as reflected by an up-regulation of IL-6, a down-regulation of PD-1 expression on T cells and in the enhancement of Ab-mediated phagocytosis. HRF is the first parasite gene which directly modulates the host immune response.
75

Velocidade de crescimento e níveis de interleucina-6 na artrite idiopática juvenil / Growth velocity and interleukin-6 levels in juvenile idiopathic arthritis

Souza, Letícia da Silva January 2008 (has links)
Objetivos: Avaliar associações da velocidade de crescimento com marcadores inflamatórios e dose cumulativa de glicorticóide em uma coorte de pacientes com Artrite Idiopática Juvenil acompanhados por 1 ano. Material e Métodos: Foram avaliados 79 pacientes com AIJ segundo critérios da ILAR. A atividade clínica da doença foi classificada por médicos reumatologistas pediátricos. Os dados antropométricos foram mensurados e classificados de acordo com as normas da Organização Mundial da Saúde. Foram utilizadas curvas de velocidade de crescimento segundo Tanner; considerou-se baixa velocidade de crescimento valores de escore Z ≤ -2. Concentrações séricas de IL-6 foram mensuradas por ELISA no período basal, e valores acima de 1 pg/ml foram considerados elevados. Resultados: Baixa velocidade de crescimento teve uma prevalência de 25,3% e esteve associada com atividade da doença no período do seguimento (p=0,085), valores elevados de IL-6 (interleucina-6) (p=0,003), velocidade de sedimentação globular (VSG) (p=0,022) e proteína C reativa (PCR) (p=0,001) e maior dosagem cumulativa de glicocorticóide (0=0,044). Na regressão linear múltipla tendo como variável dependente a velocidade de crescimento, observou-se que somente os níveis elevados de IL-6 foram independente e negativamente associados com a velocidade de crescimento (p=0,025). Conclusão: Baixa velocidade de crescimento é altamente prevalente em crianças com AIJ. Níveis elevados de IL-6 têm um importante impacto negativo no crescimento desses pacientes, enquanto a exposição ao glicocorticóide total parece ser um fator secundário. / Objective: To evaluate associations of growth velocity with inflammatory markers and cumulative dose of glucocorticoid in a cohort of patients with Juvenile Idiopathic Arthritis (JIA) followed during 1 year. Methods: Seventy-nine patients were evaluated by criteria according to the ILAR. The disease activity was evaluated by a pediatric rheumatologist. The anthropometic data were measured and classified according to the World Health Organization standards. Growth velocity curves were used according to Tanner, values below the Z-score ≤ -2 were considered low growth velocity. Serum concentrations of IL-6 were measured by ELISA in the baseline period, and values over 1pg/ml were considered as elevated. Results: The prevalence of low growth velocity was 25.3%, and it was associated with: active disease on follow-up visit (p=0,085), elevated interleukin-6 (IL-6) (p=0,003), erythrocyte sedimentation rate (ESR) (p=0,022) and C-reactive protein (CRP) (p=0,001) and higher cumulative glucocorticoid doses (0=0,044). In the multiple linear regression with growth velocity as the dependent variable, only elevated IL-6 levels were independently and negatively associated with growth velocity (p=0,025). Conclusion: Low growth velocity is highly prevalent in children with JIA. Elevated IL-6 levels seem to have an important negative impact on growth in these children, while total glucocorticoid exposure appears to be a secondary factor.
76

Carcinoma espinocelular de boca e inflamação : papel dos macrófagos no prognóstico e influência de citocinas inflamatórias no comportamento migratório / Oral squamous cell carcinoma and inflammation : role of macrophages in the prognosis and the influence of inflammatory cytokines on migratory behavior

Alves, Alessandro Menna January 2016 (has links)
O carcinoma espinocelular de boca (CEB) é a neoplasia maligna mais comum da cavidade oral, correspondendo à aproximadamente 94% dos casos dessa região. Apesar dos diversos estudos moleculares e celulares do CEB, a taxa de sobrevida dos pacientes é de aproximadamente 50%, devido principalmente ao tamanho do tumor, metástase em linfonodos regionais, grau de diferenciação das células e sítio anatômico. O microambiente tumoral do CEB, é extremamente complexo e diversificado, tendo como característica principal um estado inflamatório crônico imunossupressivo. Este microambiente é sustentado pela liberação de diferentes citocinas inflamatórias, como IL-6, TNF- - atividades exercidas tanto pelas células tumorais quanto pelas estromais. Dentre essas atividades, tem sido relatado na literatura que as citocinas inflamatórias são capazes de aumentar a migração e a capacidade de invasão das células tumorais. Entre as células estromais, os macrófagos são as mais abundantes e participam da manutenção do microambiente tumoral. De acordo com o estímulo, podem ser polarizados M1, com papel pró-inflamatório e antitumoral, e M2, com papel anti-inflamatório e pró-tumoral. O objetivo desta tese foi compreender o papel dos macrófagos no prognóstico de CEB e das citocinas inflamatórias IL-6, TNF- - linhagens celulares de CEB. Para verificar o papel dos macrófagos no prognóstico, foi realizada uma revisão sistemática na qual foram incluídos apenas os estudos que utilizavam amostra de pacientes com CEB e avaliavam o prognóstico com marcadores para macrófagos. Foi observado que maiores concentrações de macrófagos CD68+ e CD163+ estavam relacionados com pior prognóstico de pacientes com CEB, embora não tenha sido possível concluir qual região tumoral a presença destas células seja mais importante 7 para o desfecho. Para analisar o papel das citocinas inflamatórias IL-6, TNFILensaios in vitro utilizando duas linhagens celulares, SCC25 e Cal27, em condições promotoras de migração sob a influência dessas citocinas. Foi observado que a citocina IL-6 foi capaz de aumentar a velocidade de migração e a direcionalidade tanto da SCC25 quanto da Cal 27 e que esta melhora na capacidade migratória ocorreu através de um crosstalk entre a via de sinalização relacionada a IL6 (STAT3) e a via reguladora de migração celular, Rho GTPase Rac1. Estes dados reforçam o papel do microambiente tumoral no processo de progressão tumoral e sugerem potenciais alvos terapêuticos como a modulação do perfil da população de macrófagos e o papel de interleucinas no controle de invasão tecidual e metástase. / Oral squamous cell carcinoma (OSCC) is the most common malignant neoplasm of the oral cavity, corresponding to approximately 94% of the cases in this region. Despite the diverse molecular and cellular studies of OSCC, the patient survival rate is approximately 50%, mainly due to tumor size, regional lymph node metastasis, cell differentiation and anatomic site. The OSCC tumor microenvironment is extremely complex and diverse, with the main characteristic being an immunosuppressive chronic inflammatory state. This microenvironment is supported by the release of different inflammatory cytokines, such as IL-6, TNF- - and enhance the activities of both tumor and stromal cells. Among these activities, it has been reported in the literature that inflammatory cytokines are capable of increasing migration and invasiveness of tumor cells. Among stromal cells, macrophages are the most abundant and participate in the maintenance of the tumor microenvironment. According to the stimulus, macrophages can be polarized in M1, with pro-inflammatory and anti-tumoral role, and M2, with antiinflammatory and pro-tumoral role. Thus, the aim of this thesis was to evaluate the role of macrophages in the prognosis of OSCC and the influence of inflammatory cytokines IL-6, TNF- - OSCC cell lines. To assess the role of macrophages in the prognosis, a systematic review was conducted in which only studies using a sample of OSCC patients were evaluated and the prognosis was evaluated with macrophage markers. It was observed that higher concentrations of CD68 + and CD163 + macrophages were related to worse prognosis in patients with OSCC, although it was not possible to conclude which tumor region the presence of these cells is more important for the outcome. In order to analyze the role of the inflammatory cytokines IL-6, TNF- - atory 9 behavior of OSCC cells, in vitro assays using two cell lines, SCC25 and Cal27, were performed in migration-promoting conditions under the influence of these cytokines. It was observed that IL-6 was able to increase the speed migration and directionality of both SCC25 and Cal 27 and that this improvement in migratory capacity occurred through a crosstalk between the IL6-related signaling pathway (STAT3) and cell migration-related pathway, RhoGTPase Rac1. These data reinforce the role of the tumor microenvironment in the tumor progression process and suggest potential therapeutic targets such as the modulation of the profile of the macrophages population and the role of interleukins in the control of tissue invasion and metastasis.
77

Caracterização in vitro de células de cultura primária de tumores de glândula salivar : avaliação da auto-renovação e dos efeitos da IL-6 secretada por células endoteliais na fosforilação de STAT3, Akt e ERK / In vitro characterization of primary cell cultures from salivary gland tumors : analysis of self-renew and effect of IL-6 secreted by endothelial cells in the phosphorylation of STAT3, Akt and ERK

Bernardi, Lisiane January 2013 (has links)
O câncer é um problema de saúde pública mundial, apresentando acréscimo na sua incidência a cada ano. O seu processo de evolução ainda não foi completamente desvendado, dificultando a elaboração de terapias adequadas. Na busca por um melhor prognóstico, pesquisas recentes têm discutido o papel das citocinas inflamatórias, do nicho perivascular e das células-tronco nos mecanismos de desenvolvimento e manutenção dos tumores malignos. Os tumores de glândula salivar representam uma pequena porcentagem das patologias malignas da região de cabeça e pescoço, podendo ocorrer em adultos e em crianças. O diagnóstico dificilmente é precoce e a taxa de sobrevida é extremamente baixa comparada aos demais tumores da região. Assim, este estudo teve como objetivo estudar as células provenientes dos tumores de glândula salivar do tipo adenoide cístico (CAC) e adenocarcinoma NOS (AdNOS) quanto ao seu perfil imunofenotípico, quanto à existência ou não de células-tronco tumorais nessa população, bem como investigar possíveis modificações na ativação de STAT3, Akt e ERK (moléculas envolvidas em vias de sinalização de manutenção do tumor), quando em contato com fatores secretados por células endoteliais. Foram coletados 5 CACs e 4 AdNOS, no Hospital da Universidade de Michigan (Ann Arbor, MI, EUA), durante 2010 e 2012. As células foram isoladas e caracterizadas em citometria de fluxo em P0 e P7, demonstrando um perfil de células CD44+ALDH+Lin- variando de 0,33 a 3,19% e 0,36 a 2,00%, respectivamente, entre 5 linhagens avaliadas. Na avaliação por western blotting, a e-caderina, o Snail e a actina de músculo liso foram ausentes em todos os tipos tumorais, enquanto que a citoqueratina 20 (Ck20) foi presente apenas nos AdNOS. Comparando os tumores com suas metástases, a presença de Ck20, p63 e β-catenina foi semelhante, enquanto que citoqueratina 7, a vimentina e o Bmi-1 foram maiores nas metástases. Tanto os AdNOS quanto CACs apresentaram receptores para IL-6, IL-8 e EGF. Foi observado que mediadores solúveis liberados pelas células endoteliais foram capazes de fosforilar STAT3, Akt e ERK em todas as células salivares estudadas, no entanto, a proteína recombinante humana IL-6, isoladamente, não foi capaz de ativar Akt. Orosferas foram geradas em todos os tipos tumorais, demonstrando o potencial de auto-renovação celular. Um maior número de esferas foi observado nas células metastáticas em relação às primárias. Células CD44+ALDH+, comparadas com CD44-ALDH-, geraram mais esferas, quando plaqueadas em alta densidade (5.000 células). No entanto, o inverso foi encontrado, quando uma única célula foi utilizada para o ensaio (p>0,05). Devido à dificuldade de obtenção e manipulação de células de tumores de glândula salivar, ainda há muito que se investigar mecanisticamente. Considerando a fosforilação de STAT3 na presença de IL-6, semelhante ao verificado em outros tumores, o uso de anticorpos contra IL-6, talvez sejam uma opção no futuro. / Cancer is a public health problem worldwide, with an increase in incidence every year. The process of its evolution is still not completely understood, hindering the development of appropriate therapies. In the search for a better prognosis, recent reports have discussed the role of inflammatory cytokines, perivascular niche and stem cells in the mechanisms of development and maintenance of malignant tumors. The salivary gland tumors represent a small percentage of malignancies of the head and neck and can occur in both adults and children. Early diagnosis is difficult and the survival rate is extremely low compared to other tumors in the same region. Thus, this study aimed to study cells from the adenoid cystic carcinoma (ACC) and adenocarcinoma NOS (AdNOS) tumors of salivary gland regarding its immunophenotypic profile and the existence or absence of tumor stem cells in this population, as well as investigate possible changes in the activation of STAT3, Akt and ERK (molecules involved in signaling pathways of tumor maintenance), when exposed to factors secreted by endothelial cells. ACCs (n=5) and AdNOS (n=4) were collected at the Hospital of the University of Michigan (Ann Arbor, MI, USA), during 2010 to 2012. Cells were isolated and characterized by flow cytometry at P0 and P7, showing a profile of ALDH+CD44+Lin- ranging from 0.33% to 3.19% and 0.36% and 2.00%, respectively, between 5 cell lines evaluated. In the protein profile, e-cadherin, Snail and SMA were absent in all tumor types. Ck20 was present only in AdNOS. Comparing primary tumors and their metastases, the presence of Ck20, and p63 β-catenin was similar, while Ck7, vimentin and Bmi-1 were higher in metastases. Both AdNOS as ACCs had receptors for IL-6, IL-8 and EGF. It was observed that soluble mediators released by endothelial cells were able to activate STAT3, Akt and ERK phosphorylation in all cells studied. However, recombinant human IL-6 alone was not able to activate Akt. Orospheres were generated in all tumor types, indicating the potential for cellular self-renewal. Highest number of spheres was observed in metastatic cells compared to primary. ALDH+CD44+ cells compared to ALDH-CD44- generated more spheres when plated in high density (5,000 cells), however, the opposite was found when one single cell seed was evaluated (p> 0.05). There is doubt if these cell markers would be consider for a stem cell model in salivary tumors. Due to the difficulty of obtaining and manipulating salivary gland tumor cells, there is still much to investigate mechanistically. As the phosphorylation of STAT3, in the presence of IL-6, was similar to that observed in other tumors, the use of antibodies against IL-6, may be an option in the future.
78

Perfil de resposta imune in vitro a antígenos específicos do Mycobacterium tuberculosis e do polimorfismo de genes de citocinas na tuberculose – BA

Carneiro, Valdirene Leão January 2012 (has links)
Submitted by Hiolanda Rêgo (hiolandarego@gmail.com) on 2015-03-27T12:59:13Z No. of bitstreams: 1 Tese_ICS_Valdirene Leão Carneiro.pdf: 3088242 bytes, checksum: d92ff6e3e631824f84e771bf545f1b7c (MD5) / Approved for entry into archive by Flávia Ferreira (flaviaccf@yahoo.com.br) on 2015-04-30T12:47:45Z (GMT) No. of bitstreams: 1 Tese_ICS_Valdirene Leão Carneiro.pdf: 3088242 bytes, checksum: d92ff6e3e631824f84e771bf545f1b7c (MD5) / Made available in DSpace on 2015-04-30T12:47:45Z (GMT). No. of bitstreams: 1 Tese_ICS_Valdirene Leão Carneiro.pdf: 3088242 bytes, checksum: d92ff6e3e631824f84e771bf545f1b7c (MD5) / INCT-DT / Introdução: A tuberculose (TB) continua sendo um problema significativo para a saúde pública mundial. A maioria dos indivíduos expostos ao Mycobacterium tuberculosis (Mtb) persistirão infectados, embora, controlem o crescimento micobacteriano. As citocinas podem ter um papel central no controle, susceptibilidade e formas clínicas da TB, além de poderem ser utilizadas como biomarcadores de diagnóstico e prognóstico desta doença. A meta deste estudo foi investigar a possível associação entre o perfil de resposta na produção de citocinas induzida por antígenos do kit Quantiferon®-TB Gold in tube (QFT-IT) e os padrões genéticos de citocinas na tuberculose latente e ativa. Metodologia: Foram selecionados 181 voluntários divididos em três grupos: 51 indivíduos com TB pulmonar, 70 com TST positivo e 60 com TST negativo. Foram coletadas amostras de sangue para a realização do ensaio QFT-IT, imunofenotipagem dos linfócitos e extração do DNA genômico. As citocinas IL-6, IL-10, IFN-γ, TNF e TGF-β1 foram analisadas no sobrenadante do QFT-IT por citometria de fluxo e a genotipagem destas citocinas por PCR-SSP. Resultados e discussão: Houve redução significativa no número de linfócitos totais, células B, células T CD4+ e CD8+ (p <0,005, para todas as células) e aumento percentual de células NK, neutrófilos e monócitos (p=0,038, <0,0001 e <0,001, respectivamente) em pacientes com TB, quando comparados a indivíduos TST positivos e TST negativos. A sensibilidade e especificidade para o QFT-IT foram 92,1% e 80,7%, respectivamente. A concordância entre o TST e o QFT-IT foi de 0,72 (Kappa= 0,45, IC 95% 0,31-0,59). O ponto de corte de 0,30 UI/mL para o QFT-IT não altera a sensibilidade e especificidade no diagnóstico da TB ativa, contudo aumenta a sensibilidade do QFT-IT no diagnóstico da TB latente. O grupo TB apresentou maior frequência do alelo A (p=0,024) e do genótipo AA (p=0,027) IFN-γ +874 em relação aos demais grupos do estudo, sendo que nesse grupo células sanguíneas de indivíduos com genótipo AA apresentaram menores valores de IFN-γ quando estimuladas com a PHA. Para o polimorfismo das outras citocinas não houve diferença significativa entre os grupos do estudo. Sob estímulo da PHA foi observada uma menor produção das citocinas IFN-γ, IL-10 e TNF para o grupo TB em relaçao aos demais. Quando comparada a produção de IL-6 sem estímulo e estimulada com antígenos do Mtb, por grupo de estudo, foi observada uma redução dessa citocina (p= 0,001; <0,0001 e <0,0002 para os grupos TB, TST positivo e TST negativo, respectivamente). Conclusões: O QFT-IT tem concordância moderada com o TST e o ponto de corte de 0,30 UI/mL pode melhorar a sensibilidade para o diagnóstico da TB latente sem perda da especificidade. A imunossupressão sistêmica observada nos pacientes com tuberculose pode levar a diminuição na produção de IL-10, TNF e IFN-γ pelas células sanguíneas quando estimuladas com a PHA. Os antígenos do Mtb podem modulam a resposta imune do hospedeiro por inibir a produção de IL-6 contribuindo para a gravidade da tuberculose. Apesar, do alelo A e o genótipo AA de IFN-γ (+874) estarem associados com a tuberculose e a menor produção de IFN-γ, não há interferência deste polimorfismo sobre o resultado do teste QFT-IT.
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Velocidade de crescimento e níveis de interleucina-6 na artrite idiopática juvenil / Growth velocity and interleukin-6 levels in juvenile idiopathic arthritis

Souza, Letícia da Silva January 2008 (has links)
Objetivos: Avaliar associações da velocidade de crescimento com marcadores inflamatórios e dose cumulativa de glicorticóide em uma coorte de pacientes com Artrite Idiopática Juvenil acompanhados por 1 ano. Material e Métodos: Foram avaliados 79 pacientes com AIJ segundo critérios da ILAR. A atividade clínica da doença foi classificada por médicos reumatologistas pediátricos. Os dados antropométricos foram mensurados e classificados de acordo com as normas da Organização Mundial da Saúde. Foram utilizadas curvas de velocidade de crescimento segundo Tanner; considerou-se baixa velocidade de crescimento valores de escore Z ≤ -2. Concentrações séricas de IL-6 foram mensuradas por ELISA no período basal, e valores acima de 1 pg/ml foram considerados elevados. Resultados: Baixa velocidade de crescimento teve uma prevalência de 25,3% e esteve associada com atividade da doença no período do seguimento (p=0,085), valores elevados de IL-6 (interleucina-6) (p=0,003), velocidade de sedimentação globular (VSG) (p=0,022) e proteína C reativa (PCR) (p=0,001) e maior dosagem cumulativa de glicocorticóide (0=0,044). Na regressão linear múltipla tendo como variável dependente a velocidade de crescimento, observou-se que somente os níveis elevados de IL-6 foram independente e negativamente associados com a velocidade de crescimento (p=0,025). Conclusão: Baixa velocidade de crescimento é altamente prevalente em crianças com AIJ. Níveis elevados de IL-6 têm um importante impacto negativo no crescimento desses pacientes, enquanto a exposição ao glicocorticóide total parece ser um fator secundário. / Objective: To evaluate associations of growth velocity with inflammatory markers and cumulative dose of glucocorticoid in a cohort of patients with Juvenile Idiopathic Arthritis (JIA) followed during 1 year. Methods: Seventy-nine patients were evaluated by criteria according to the ILAR. The disease activity was evaluated by a pediatric rheumatologist. The anthropometic data were measured and classified according to the World Health Organization standards. Growth velocity curves were used according to Tanner, values below the Z-score ≤ -2 were considered low growth velocity. Serum concentrations of IL-6 were measured by ELISA in the baseline period, and values over 1pg/ml were considered as elevated. Results: The prevalence of low growth velocity was 25.3%, and it was associated with: active disease on follow-up visit (p=0,085), elevated interleukin-6 (IL-6) (p=0,003), erythrocyte sedimentation rate (ESR) (p=0,022) and C-reactive protein (CRP) (p=0,001) and higher cumulative glucocorticoid doses (0=0,044). In the multiple linear regression with growth velocity as the dependent variable, only elevated IL-6 levels were independently and negatively associated with growth velocity (p=0,025). Conclusion: Low growth velocity is highly prevalent in children with JIA. Elevated IL-6 levels seem to have an important negative impact on growth in these children, while total glucocorticoid exposure appears to be a secondary factor.
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Citocinas pró-inflamatórias em ratos experimentalmente infectados por Trypanosoma evansi / Pro-inflammatory cytokines in rats experimentally infected with Trypanosoma evansi

Paim, Francine Chimelo 28 February 2011 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The aim of this study was to measure the levels of interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), interleukin 1 (IL-1) and interleukin 6 (IL-6) in serum of rats experimentally infected with Trypanosoma evansi and to correlate with the hematological parameters. Seventy-six rats (Wistar) were divided into two groups. Group C (control) composed of twenty-eight non-inoculated rats distributed in four subgroups with seven animals each (C3, C5, C10 and C20), which received 0.2 mL saline by intraperitoneally. The group T (infected) formed of forty-eight rats was inoculated intraperitoneally with cryopreserved blood containing 1x106 trypomastigotes per animal. These, eight animals died between 5th -7th days post-infection. The remaining animals were divided into four subgroups with ten animals (T3, T5, T10 and T20) according to parasitemia degree. The blood samples were collected by cardiac puncture at the day 3 (C3, T3), 5 (C5, T5), 10 (C10, T10) and 20 (C20, T20) post infection (pi) to perform the complete blood count and determination of IFN-γ, TNF-α, IL-1 and IL-6 levels using an ELISA quantitative sandwich. Immediately after collection the animals were euthanized. The levels of all measured cytokines increased significantly (P < 0.01) in infected animals compared to the controls. T. evansi infection in rats caused an increase in serum IFN-γ, TNF-α, IL-1 and IL-6 and this increase was observed during the whole experimental infection. In addition, the increase in the cytokine levels was concomitant and directly correlated with parasitemia and anemia development at the parasitemia peak. These results suggest a synergism between these cytokines contributing to the development of anemia and the regulation of the immune response against the parasite. / O objetivo deste estudo foi avaliar os níveis séricos das citocinas pró-inflamatórias interferon-gama (INF-γ), fator de necrose tumoral-alfa (TNF-α), interleucina 1 (IL-1) e interleucina 6 (IL-6) em ratos experimentalmente infectados por Trypanosoma evansi e estabelecer uma correlação com os parâmetros hematológicos. Setenta e seis ratos (Wistar) machos foram divididos em dois grupos experimentais. O Grupo C (controle) foi composto por vinte e oito ratos não inoculados distribuídos em quatro subgrupos com sete animais cada (C3, C5, C10 e C20), que receberam 0,2 mL de solução fisiológica pela via intraperitoneal. O grupo T (infectados) formado por quarenta e oito ratos inoculados intraperitonealmente com sangue criopreservado, contendo 1x106 tripomastigotas de T. evansi por animal. Destes, oito morreram entre o 5º e 7º dia pós-infecção. Os animais restantes foram divididos em quatro subgrupos de dez animais cada (T3, T5, T10 e T20) de acordo com o grau de parasitemia. As amostras de sangue foram coletadas por punção cardíaca, nos dias 3 (C3, T3), 5 (C5, T5), 10 (C10, T10) e 20 (C20,T20) pós-infecção (pi) para a realização do hemograma e determinação dos níveis séricos de INF-γ, TNF-α, IL-1 e IL-6 pela técnica de ELISA tipo sanduíche. Imediatamente após as coletas os animais eram submetidos à eutanásia. Os níveis de citocinas pró-inflamatórias aumentaram significativamente (P<0,01) nos animais infectados em relação ao grupo controle. A infecção por T. evansi em ratos provocou um aumento nos níveis séricos de INF-γ, TNF-α, IL-1, IL-6 e esse aumento foi observado durante toda a infecção experimental. Além disso, o aumento nos níveis de citocinas foi diretamente correlacionado com a parasitemia e o desenvolvimento da anemia. Estes resultados sugerem um sinergismo entre essas citocinas contribuindo para o desenvolvimento da anemia e regulação da resposta imune contra o parasito.

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