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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.
31

Intracellular signal transduction mechanisms regulating the activation of eosinophils in allergic inflammation. / CUHK electronic theses & dissertations collection

January 2007 (has links)
All of the above findings demonstrated that eosinophil activation in allergic inflammation could be sensitively regulated by diverse stimuli. Besides, highly redundant functional effects and underlying signaling mechanisms were observed among different mediators. Elucidation of the mechanisms of eosinophil activation could improve our understanding of its complex and active role in the pathogenesis of allergic diseases, thereby providing biochemical basis for the development of more effective therapeutic strategies for treating the diseases. (Abstract shortened by UMI.) / Apart from the cytokines produced by T lymphoctyes, leptin, a cytokine produced by adipocytes, was also demonstrated to activate eosinophils. It was reported that the plasma levels of leptin were elevated in both obese and allergic patients. We found that leptin could activate eosinophils for survival enhancement, adhesion and migration, and secretion of cytokines and chemokines. Besides, we showed that the MAPKs and NF-kappaB pathways were involved in eosinophil adhesion, migration and mediator release induced by leptin, while Janus kinases (JAK)-signal transducers and activators of transcription (STAT) pathway was responsible for leptin-induced eosinophil survival. Our study indicated a potential correlation between obesity and exacerbation of allergic inflammation. / Eosinophilia is a hallmark pathological feature of allergic diseases and it has been targeted as a novel therapeutic strategy for allergic diseases. / In atopic dermatitis (AD), dermal infiltration of eosinophils is one of the pathological features of this disease. IL-31 is a novel Th2 cytokine reported to induce pruritus and skin dermatitis resembling human AD. Our study on the co-culture system of eosinophils and keratinocyte cell line HaCaT illustrated the production of pro-inflammatory cytokines and chemokines from the co-culture system of eosinophils and HaCaT cells, under the stimulation of IL-31. In co-culture system, surface expression of CD18 and intercellular adhesion molecule (ICAM)-1 on eosinophils and HaCaT cells was also up-regulated respectively, implying a direct interaction between the two cell types through their cell surface adhesion molecules. The interaction of eosinophils and HaCaT cells under IL-31 stimulation was shown to be mediated through MAPKs, NF-kappaB and PI3K pathways. These findings therefore elucidate the immunological roles of IL-31, eosinophils and keratinocytes in AD. / In the present study, we investigated the mechanisms of eosinophil activation induced by various stimuli including novel T helper type 2 (Th2) cytokines, adipokine, microbial products and direct interaction with tissue cells. The activation of eosinophils was studied in terms of survival enhancement, modulation of adhesion and migration, and the release of inflammatory mediators including cytokines, chemokines, granular proteins and superoxide. Using pharmacological and molecular approaches, we further investigated the intracellular signaling mechanisms regulating the eosinophil activation mediated by various stimuli. / Increasing evidence has indicated that bacterial and viral infections could intensify allergic responses. Our findings demonstrated that eosinophil activation could be elicited by microbes through toll-like receptors (TLRs), the recently discovered receptors for the recognition of conserved motifs in pathogens. We found that eosinophils could be activated by the ligands of TLR2, 5 and 7 in enhancing survival, adhesion and migration, release of pro-inflammatory cytokines, chemokines, granular proteins and superoxides. These stimulatory effects, mediated by TLR2, 5 and 7, were differentially regulated by MAPKs, NF-kappaB and phosphatidylinositol 3-kinase (PI3K) pathways. Moreover, an important finding of our study is the common involvement of focal adhesion kinase (FAK)-dependent extracellular-regulated protein kinase (ERK) phosphorylation in the signaling of TLR 2, 5 and 7, implying a special role of FAK in linking TLR signaling with MAPKs cascade in human eosinophils. Our study on microbe-induced eosinophil activation provided a potential explanation for linking infection with exacerbation of allergic diseases. / The interleukin (IL)-17 family is a newly discovered group of cytokines which was reported to be important in allergic inflammation. We studied the roles of two IL-17 family members, IL-175E/IL-25 and IL-17F on eosinophil activation. Both cytokines were found to induce the secretion of inflammatory cytokines and chemokines from eosinophils, in which IL-25 could also enhance eosinophil survival and adhesion. Besides, we found that the stimulatory effects induced by both IL-25 and IL-17F were mediated through mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-kappaB) pathways. The main source of IL-17F has recently been reported to be a novel T lymphocyte population, Th17, which is specifically driven by IL-23. An important finding of our present study was the synergistic effects of IL-17F and its potent inducer, IL-23, on cytokine release from eosinophils. Since IL-23 was produced by macrophages and dendritic cells upon microbial stimulation, the synergistic effect of IL-17F and IL-23 on eosinophil activation might imply a potential role in linking microbial infection and allergic inflammation. Our findings also provide further support to the crucial role of the IL-17 family and Th17 lymphocytes in the amplification of allergic diseases. / Cheung, Fung Yi. / Source: Dissertation Abstracts International, Volume: 69-03, Section: B, page: 1552. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 205-221). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
32

Eosinófilos duodenais : potencial associação com a infecção pelo Helicobacter pylori e com os sintomas da dispepsia funcional

Mazzoleni, Felipe January 2017 (has links)
Introdução e objetivos: Eosinofilia duodenal está associada com parasitoses intestinais e com alergias alimentares, e tem sido sugerida como possível fator etiológico da dispepsia funcional, pela capacidade de causar alterações na motilidade e na sensibilidade do aparelho digestivo. Sua relação com o Helicobacter pylori é pouco conhecida, tendo sido avaliada apenas como achado secundário em alguns estudos, com resultados controversos. Esse estudo tem como objetivos avaliar o papel da infecção gástrica pelo H. pylori no número de eosinófilos duodenais e avaliar a relação dos eosinófilos duodenais com os sintomas da dispepsia funcional. Métodos: foram avaliados 100 pacientes dispépticos funcionais, de acordo com os critérios de Roma III, dos quais 50 foram H. pylori positivos e 50 negativos. Os pacientes foram submetidos à endoscopia digestiva alta com biópsias gástricas e duodenais. A positividade do H. pylori foi avaliada pelo teste de urease e pelo exame histológico (Hematoxilina-eosina e Giemsa). As biópsias duodenais foram avaliadas com hematoxilina-eosina e a número de eosinófilos duodenais foi quantificada pela média de eosinófilos por 5 campos de grande aumento (CGA) aleatórios e não sobrepostos. Eosinofilia duodenal foi definida pela presença de >22 eosinófilos/CGA. As medianas das médias aritméticas dos eosinófilos duodenais por cinco CGA foram comparadas entre os pacientes H. pylori positivos e negativos. Também foi avaliada a relação do número de eosinófilos duodenais com a intensidade e tipo de sintomas dispépticos, determinados por questionário validado (PADYQ). Os eosinófilos duodenais foram avaliados para variáveis demográficas e endoscópicas. Resultados: Pacientes do sexo feminino representaram 88% da amostra e a idade média foi de 41,7 anos As características basais dos pacientes H. pylori positivos e H. pylori negativos foram semelhantes. Apenas um paciente, no grupo H. pylori positivo, apresentou eosinofilia duodenal. As medianas dos eosinófilos duodenais/CGA foram 4,6 [P25-75: 2,8-7,2] nos pacientes H. pylori negativos e 4,7 [P25-75: 3,4-8,4] nos H. pylori positivos (p= 0,403). O número de eosinófilos 8 duodenais foi significativamente maior em pacientes com sintomas mais intensos: pacientes com escore do PADYQ >22 (>50% da pontuação máxima) apresentaram mediana de eosinófilos duodenais/CGA de 5,4 [P25-75: 3,4–7,6] e pacientes com escore ≤22 de 3,4 [P25-75: 2,2–6,0] (p= 0,018). Os pacientes foram divididos em tercis, de acordo com a intensidade dos sintomas: grupo 1 com 31 pacientes (sintomas leves); grupo 2 com 30 pacientes (sintomas moderados); e grupo 3 com 31 pacientes (sintomas acentuados). A mediana dos eosinófilos duodenais/CGA no grupo 1 foi de 3,4 [P25-75: 2,2 -6,0]; no grupo 2 de 4,7 [P25-75: 3,2-6,4]; e o grupo 3 de 5,8 [P25-75: 3,6-8,2] (P=0,033). Houve diferença estatisticamente significativa no número de eosinófilos duodenais entre fumantes e não fumantes (p= 0,030) e entre pacientes com índice de massa corporal (IMC) <25 kg/m2 e IMC ≥ 25 kg/m2 (p= 0,035). Na análise multivariada por regressão linear, os fatores que tiveram influência sobre o número de eosinófilos duodenais foram o tabagismo (p= 0,026) e a intensidade dos sintomas dispépticos (p= 0,039). Conclusões: Esse estudo não mostrou associação entre a infecção pelo H. pylori e a contagem de eosinófilos duodenais, nessa população de pacientes dispépticos funcionais. Entretanto, foi demonstrada uma relação diretamente proporcional e estatisticamente significativa entre o número de eosinófilos duodenais e a intensidade dos sintomas dispépticos. / Background and Aims: Duodenal eosinophilia is associated with intestinal parasitosis and food allergies. It has also been implicated as a potential factor on the etiology of functional dyspepsia, probably by causing changes in digestive tract motility and sensitivity. The association with Helicobacter pylori is poorly understood, and has been only evaluated as a secondary finding in 9 previous studies, with conflicting results. This study aims to evaluate the potential role of gastric H. pylori infection in the duodenal eosinophil count, and the influence of duodenal eosinophils on symptoms in functional dyspeptic subjects. Methods: One hundred functional dyspeptic subjects, according to Rome III criteria, were evaluated, and 50 were H. pylori positive and 50 H. pylori negative. Patients were submitted to upper gastrointestinal endoscopy with gastric and duodenal biopsies. H. pylori positivity was evaluated by urease test and gastric histology (Hematoxylin-eosin and Giemsa). Duodenal biopsies were evaluated with Hematoxylin-Eosin staining, and the duodenal eosinophil count was determined by the mean of eosinophil by 5 random nonoverlapping high power fields (HPF). Duodenal eosinophilia was defined as >22 eosinophils/HPF. The median of the arithmetic means of the duodenal eosinophils counts per high power field were compared between H. pylori positive and H. pylori negative subjects. The relationship between the number of duodenal eosinophils and the intensity and type of dyspeptic symptoms was determined by validated questionnaire (PADYQ). Duodenal eosinophils counts were also evaluated by demographic variables and endoscopic findings. Results: 88% of the subjects were female and the mean age was 41.7 years. Baseline characteristics were similar between H. pylori positive and H. pylori negative subjects. Only one patient, in the H. pylori positive group, had duodenal eosinophilia. The median duodenal eosinophils/HPF were 4.6 [Percentiles 25-75(P25-75): 2.8-7.2] in H. pylori negative and 4.7 [P25-75: 3.4-8.4] in H. pylori positive subjects (p= 0.403). The duodenal eosinophil count was greater in subjects with higher symptoms severity: patients with PADYQ score more than 22 (>50% of the maximum score) had median duodenal eosinophil/HPF of 5.4 [P25-75: 3,4–7,6] and subjects with PADYQ score ≤22 of 3.4 [P25-75: 2.2–6.0] (p= 0.018). The patients were divided into terciles, according to symptoms severity: group 1 with 31 subjects (mild symptoms); group 2 with 30 subjects (moderate symptoms); and group 3 with 31 subjects (severe symptoms). 10 The median duodenal eosinophils/HPF was 3.4 [P25-75: 2.2-6.0] in group 1; 4.7 [P25-75: 3.2-6.4] in group 2; and 5.8 [P25-75: 3.6-8.2] in group 3 (p=0.033). There was a higher duodenal eosinophils count in smokers (current or former) (p=0.030), and subjects with BMI ≥ 25 kg/m2 (p=0.035). In the multivariate analysis by linear regression, the duodenal eosinophil count were influenced by smoking (p = 0.026) and dyspeptic symptoms severity (p= 0.039). Conclusion: This study did not show an association between H. pylori infection and the number of duodenal eosinophils, in this population of functional dyspeptic patients. However, a directly proportional and statistically significant relationship between the number of duodenal eosinophils and the intensity of dyspeptic symptoms has been demonstrated.
33

Activation of human eosinophils by novel t-helper type 2 cytokine IL-33: implications for the immunopathology of allergic inflammation.

January 2009 (has links)
Chow, Yin Sau Joyce. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 127-140). / Abstract also in Chinese. / Abstract --- p.I / 摘要 --- p.V / Acknowledgements --- p.VIII / Publications --- p.X / Table of contents --- p.XII / Abbreviations --- p.XV / Chapter Chapter 1: --- General Introduction --- p.1 / Chapter 1.1 --- Allergic diseases and allergic inflammation --- p.1 / Chapter 1.1.1 --- Allergic diseases and their prevalence --- p.1 / Chapter 1.1.2 --- Immunopathology of allergic inflammation --- p.2 / Chapter 1.2 --- Biology of human eosinophils --- p.4 / Chapter 1.2.1 --- Morphology --- p.4 / Chapter 1.2.2 --- Cell surface receptors and mediators --- p.4 / Chapter 1.2.3 --- Origin and development of eosinophils --- p.7 / Chapter 1.3 --- Eosinophils and allergic inflammation --- p.7 / Chapter 1.3.1 --- Adhesion molecules on eosinophils for emigration --- p.8 / Chapter 1.3.2 --- Eosinophil activation and inflammatory mediators --- p.13 / Chapter 1.3.3 --- Survival of eosinophils in allergic inflammation --- p.18 / Chapter 1.3.4 --- Immunopathological roles of eosinophils in allergic inflammation --- p.18 / Chapter 1.4 --- Intracellular signaling mechanisms --- p.20 / Chapter 1.4.1 --- Signal transduction pathways of eosinophils --- p.20 / Chapter 1.4.2 --- Inhibitors of signaling molecules --- p.26 / Chapter 1.5 --- Aim of study --- p.29 / Chapter Chapter 2: --- Materials and Methods --- p.31 / Chapter 2.1 --- Materials --- p.31 / Chapter 2.1.1 --- Human eosinophils --- p.31 / Chapter 2.1.2 --- Cell culture --- p.33 / Chapter 2.1.3 --- Cell surface and intracellular immunofluorescent staining --- p.36 / Chapter 2.1.4 --- Detection of cytokine and chemokine release --- p.39 / Chapter 2.1.5 --- Detection of cell viability and apoptosis --- p.40 / Chapter 2.1.6 --- Protein extraction --- p.40 / Chapter 2.1.7 --- Western blot analysis --- p.40 / Chapter 2.1.8 --- Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) --- p.42 / Chapter 2.2 --- Methods --- p.45 / Chapter 2.2.1 --- Purification of human eosinophils --- p.45 / Chapter 2.2.2 --- Cell culture --- p.46 / Chapter 2.2.3 --- Cell surface and intracellular immunofluorescent staining --- p.47 / Chapter 2.2.4 --- Detection of cytokine and chemokine release --- p.48 / Chapter 2.2.5 --- Detection of cell viability and apoptoas --- p.49 / Chapter 2.2.6 --- Protein extraction --- p.49 / Chapter 2.2.7 --- Western blot analysis --- p.50 / Chapter 2.2.8 --- SDS-PAGE --- p.50 / Chapter 2.2.9 --- Statistical analysis --- p.51 / Chapter Chapter 3: --- Role of Novel IL-1 Family Cytokine in Allergic Inflammation: IL-33-mediated Eosinophil Activation --- p.52 / Chapter 3.1 --- Introduction --- p.52 / Chapter 3.2 --- Results --- p.54 / Chapter 3.2.1 --- "Total protein expression of IL-33 receptor, ST2, of human eosinophils" --- p.54 / Chapter 3.2.2 --- "Intracellular protein expression of IL-33 receptor, ST2,in human eosinophils" --- p.55 / Chapter 3.2.3 --- "Extracellular protein expression of IL-33 receptor, ST2, on human eosinophils" --- p.56 / Chapter 3.2.4 --- "Effects of IL-1β IL-18, and IL-33 on survival of human eosinophils" --- p.57 / Chapter 3.2.5 --- "Effects of IL-1β, IL-18, and DL-33 on surface adhesion molecule expression on human eosinophils" --- p.60 / Chapter 3.2.6 --- "Effects of IL-1β, IL-18, and IL-33 on chemokine and cytokine release from human eosinophils" --- p.64 / Chapter 3.2.7 --- "Synergistic effects of IL-1β, IH8, and IL-33 on IL-6 release from human eosinophils" --- p.69 / Chapter 3.2.8 --- "Effects of transcription and translation inhibitors on IL- 1β, IL-18, and IL-33-induced chemokine and cytokine release from human eosinophils" --- p.71 / Chapter 3.2.9 --- "Effects of different inhibitors on lL-1β, IL-18, and IL-33-induced survival enhancement of human eosinophils" --- p.75 / Chapter 3.2.10 --- Effects of different inhibitors on IL-1β and IL-33-mediated surface expression of adhesion molecules on human eosinophils --- p.77 / Chapter 3.2.11 --- "Effects of different inhibitors on IL-33, IL-1β,and IL-18-induced release of CCL2,CXCL8,and IL-6 from human eosinophils" --- p.79 / Chapter 3.2.12 --- "Effects of IL-33, IL-1β and IL-18 on activation of ERK, p38 MAPK, and NF-kB pathways in human eosinophils" --- p.83 / Chapter 3.3 --- Discussion --- p.85 / Chapter Chapter 4: --- Co-culture of Eosinophils & Epidermal Keratinocytes Upon IL-33 Stimulation: Implications for Immunopathology of Atopic Dermatitis --- p.95 / Chapter 4.1 --- Introduction --- p.95 / Chapter 4.2 --- Results --- p.98 / Chapter 4.2.1 --- Effect of IL-33 on surface expression of CD18 and ICAM-1 upon the interaction of human eosinophils and epidermal keratinocytes --- p.98 / Chapter 4.2.2 --- Effect of IL-33 on CCL2 release upon the interaction of human eosinophils and epidermal keratinocytes --- p.98 / Chapter 4.2.3 --- Effect of IL-33 on CXCL8 release upon the interaction of human eosinophils and epidermal keratinocytes --- p.101 / Chapter 4.2.4 --- Effect of IL-33 on IL-6 release upon the interaction of human eosinophils and epidermal keratinocytes --- p.101 / Chapter 4.2.5 --- Source(s) of CCL2 in co-culture of human eosinophils and epidermal keratinocytes upon IL-33 stimulation --- p.104 / Chapter 4.2.6 --- Source(s) of CXCL8 in co-culture of human eosinophils and epidermal keratinocytes upon IL-33 stimulation --- p.105 / Chapter 4.2.7 --- Source(s) of IL-6 in co-culture of human eosinophils and epidermal keratinocytes upon BL-33 stimulation --- p.108 / Chapter 4.2.8 --- "Effect of transwell insert on the induction of CCL2,CXCL8, and IL-6 release in co-culture of human eosinophils and epidermal keratinocytes upon IL-33 stimulation" --- p.110 / Chapter 4.3 --- Discussion --- p.113 / Chapter Chapter 5: --- Concluding Remarks and Future Perspectives --- p.120 / Chapter 5.1 --- Concluding Remarks --- p.120 / Chapter 5.2 --- Future Perspectives --- p.123 / Appendix --- p.126 / References --- p.127
34

Intracellular regulatory mechanisms of the activation of human eosinophils by TSLP, IL-27 and ligands of NOD-like receptors in allergic inflammation. / CUHK electronic theses & dissertations collection

January 2010 (has links)
Accumulating evidence has indicated that microbial infection could intensify allergic responses. Previous findings demonstrated that eosinophil activation could be elicited by bacterial and viral conserved molecular pattern through TLR. Recently, two cytoplasmic pattern recognition receptors, NLR protein NOD1 and NOD2, have been discovered and the important roles in innate immunity have been elucidated. Eosinophils alone have little responses upon the stimulation with ligands of NOD1 and NOD2. Since airway eosinophils increase in more numbers of asthmatic patients compared to control subjects, we investigated the co-culture system of eosinophils and human bronchial epithelial cells to illustrate the potential immunopathological roles of NOD1 and NOD2 in asthma processes. In the co-culture system, NOD1 ligand gamma-D-Glu-mDAP (iE-DAP) and NOD2 ligand muramyl dipeptide (MDP) could upregulate cell surface expression of CD1 8 and ICAM-1 on eosinophils and ICAM-1 and vascular cell adhesion molecule-1 (VCAM-1) on bronchial epithelial cells, as well as induce chemokines CCL2 and CXCL8 release. These findings therefore imply the direct interaction and activation between the two cells upon NOD1 and NOD2 ligand stimulation. / Allergic diseases are prevalent and their incidences have been increasing worldwide. Eosinophils are the principal effector cells for the late phase response in allergic inflammation. The infiltration of eosinophils together with other inflammatory cells at the local inflammatory sites is the major characteristic in allergic inflammation. However, the detailed innnunopathological responses and mechanisms of the activation of eosinophils in allergic inflammation are not well defined. In the present study, we investigated and attempted to elucidate the mechanisms of eosinophil activation induced by various stimuli, including thymic stromal lymphopoietin (TSLP), the novel interleukin (IL)-12 family cytokine IL-27, and ligands of nucleotide-binding oligomerization domain (NOD) like receptor (NLR) protein NOD1 and NOD2 upon interaction with bronchial epithelial cells. / In conclusion, the above findings demonstrated that eosinophils could be potently activated by diverse stimuli and regulated by multiple intracellular regulatory mechanisms. The elucidation of eosinophil activation may offer new therapeutic stategies and clues for the treatment of allergic diseases. / Recently, the novel IL-12 family member IL-27 was found to regulate immune responses, exerting either stimulation or suppression effects. We found that eosinophils constitutively expressed IL-27 receptor heterodimer, gp130 and WSX-1. IL-27 could prolong eosinophil survival by reducing apoptosis, modulate the expression of adhesion molecules to facilitate eosinophil adhesion and accumulation, and induce the release of proinflammatory cytokines IL-6, tumor necrosis factor (TNF)-aalpha IL-1beta and chemokines CCL2, CXCL8 and CXCL1. The stimulatory effects of IL-27 on eosinophils could not be abrogated by IL-25, hematopoietic cytokine granulocyte-macrophage colony stimulating factor (GM-CSF) and toll-like receptor (TLR) 4 ligand lipopolysaccharide (LPS). These findings were different from the effects of IL-27 and LPS on monocytes. Intracellular signaling mechanistic studies showed that IL-27-mediated eosinophil activation was differentially regulated by MAPKs and NF-kappaB. Based on the above results, IL-27 could play crucial roles in allergic diseases by the activation of eosinophils via differential intracellular signaling cascades. However, IL-27 has been shown to suppress allergic diseases in mouse models. According to our findings of its activating effects on human eosinophils, IL-27 may play pleiotropic roles in human allergic responses. / TSLP is a novel IL-7-like cytokine highly expressed by bronchial epithelial cells and skin keratinocytes in allergic diseases. TSLP acts as a master switch for allergic inflammation through the activation of dendritic cells and mast cells for initiating inflammatory Th2 responses. To elucidate the immunological cascades of epithelium/keatinocyte-eosinophil mediated allergic inflammation, we examined the modulating effects of TSLP on human eosinophils. We observed that human eosinophils constitutively expressed TSLP receptor complex comprising TSLP-binding chain TSLPR and IL-7Ralpha chain. TSLP could significantly delay eosinophil apoptosis, up-regulate the cell surface expression of adhesion molecule CD18 and intercellular adhesion molecule-1 (ICAM-1) but down-regulate L-selectin, enhance eosinophil adhesion to fibronectin, and induce the release of inflammatory cytokine 1L-6 and chemokines CXCL8, CXCL1 and CCL2. All these effects were concentration-dependent and TSLP-specific. TSLP regulated the above effects through the activation of extracellular signal-regulated protein kinase (ERK), p38 mitogen activated protein kinase (MAPK) and nuclear factor (NF)-kappaB signaling pathway, but not signal transducer and activator of transcription (STAT)-5 and STAT-3 which were usually activated in other effector cells upon TSLP stimulation. Collectively, the above findings elucidated the pro-allergic mechanisms of TSLP via the activation of distinct intracellular signaling pathways in eosinophils. / Hu, Shuiqing. / Adviser: Wong Chin Kwok. / Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 176-216). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
35

Eosinófilos duodenais : potencial associação com a infecção pelo Helicobacter pylori e com os sintomas da dispepsia funcional

Mazzoleni, Felipe January 2017 (has links)
Introdução e objetivos: Eosinofilia duodenal está associada com parasitoses intestinais e com alergias alimentares, e tem sido sugerida como possível fator etiológico da dispepsia funcional, pela capacidade de causar alterações na motilidade e na sensibilidade do aparelho digestivo. Sua relação com o Helicobacter pylori é pouco conhecida, tendo sido avaliada apenas como achado secundário em alguns estudos, com resultados controversos. Esse estudo tem como objetivos avaliar o papel da infecção gástrica pelo H. pylori no número de eosinófilos duodenais e avaliar a relação dos eosinófilos duodenais com os sintomas da dispepsia funcional. Métodos: foram avaliados 100 pacientes dispépticos funcionais, de acordo com os critérios de Roma III, dos quais 50 foram H. pylori positivos e 50 negativos. Os pacientes foram submetidos à endoscopia digestiva alta com biópsias gástricas e duodenais. A positividade do H. pylori foi avaliada pelo teste de urease e pelo exame histológico (Hematoxilina-eosina e Giemsa). As biópsias duodenais foram avaliadas com hematoxilina-eosina e a número de eosinófilos duodenais foi quantificada pela média de eosinófilos por 5 campos de grande aumento (CGA) aleatórios e não sobrepostos. Eosinofilia duodenal foi definida pela presença de >22 eosinófilos/CGA. As medianas das médias aritméticas dos eosinófilos duodenais por cinco CGA foram comparadas entre os pacientes H. pylori positivos e negativos. Também foi avaliada a relação do número de eosinófilos duodenais com a intensidade e tipo de sintomas dispépticos, determinados por questionário validado (PADYQ). Os eosinófilos duodenais foram avaliados para variáveis demográficas e endoscópicas. Resultados: Pacientes do sexo feminino representaram 88% da amostra e a idade média foi de 41,7 anos As características basais dos pacientes H. pylori positivos e H. pylori negativos foram semelhantes. Apenas um paciente, no grupo H. pylori positivo, apresentou eosinofilia duodenal. As medianas dos eosinófilos duodenais/CGA foram 4,6 [P25-75: 2,8-7,2] nos pacientes H. pylori negativos e 4,7 [P25-75: 3,4-8,4] nos H. pylori positivos (p= 0,403). O número de eosinófilos 8 duodenais foi significativamente maior em pacientes com sintomas mais intensos: pacientes com escore do PADYQ >22 (>50% da pontuação máxima) apresentaram mediana de eosinófilos duodenais/CGA de 5,4 [P25-75: 3,4–7,6] e pacientes com escore ≤22 de 3,4 [P25-75: 2,2–6,0] (p= 0,018). Os pacientes foram divididos em tercis, de acordo com a intensidade dos sintomas: grupo 1 com 31 pacientes (sintomas leves); grupo 2 com 30 pacientes (sintomas moderados); e grupo 3 com 31 pacientes (sintomas acentuados). A mediana dos eosinófilos duodenais/CGA no grupo 1 foi de 3,4 [P25-75: 2,2 -6,0]; no grupo 2 de 4,7 [P25-75: 3,2-6,4]; e o grupo 3 de 5,8 [P25-75: 3,6-8,2] (P=0,033). Houve diferença estatisticamente significativa no número de eosinófilos duodenais entre fumantes e não fumantes (p= 0,030) e entre pacientes com índice de massa corporal (IMC) <25 kg/m2 e IMC ≥ 25 kg/m2 (p= 0,035). Na análise multivariada por regressão linear, os fatores que tiveram influência sobre o número de eosinófilos duodenais foram o tabagismo (p= 0,026) e a intensidade dos sintomas dispépticos (p= 0,039). Conclusões: Esse estudo não mostrou associação entre a infecção pelo H. pylori e a contagem de eosinófilos duodenais, nessa população de pacientes dispépticos funcionais. Entretanto, foi demonstrada uma relação diretamente proporcional e estatisticamente significativa entre o número de eosinófilos duodenais e a intensidade dos sintomas dispépticos. / Background and Aims: Duodenal eosinophilia is associated with intestinal parasitosis and food allergies. It has also been implicated as a potential factor on the etiology of functional dyspepsia, probably by causing changes in digestive tract motility and sensitivity. The association with Helicobacter pylori is poorly understood, and has been only evaluated as a secondary finding in 9 previous studies, with conflicting results. This study aims to evaluate the potential role of gastric H. pylori infection in the duodenal eosinophil count, and the influence of duodenal eosinophils on symptoms in functional dyspeptic subjects. Methods: One hundred functional dyspeptic subjects, according to Rome III criteria, were evaluated, and 50 were H. pylori positive and 50 H. pylori negative. Patients were submitted to upper gastrointestinal endoscopy with gastric and duodenal biopsies. H. pylori positivity was evaluated by urease test and gastric histology (Hematoxylin-eosin and Giemsa). Duodenal biopsies were evaluated with Hematoxylin-Eosin staining, and the duodenal eosinophil count was determined by the mean of eosinophil by 5 random nonoverlapping high power fields (HPF). Duodenal eosinophilia was defined as >22 eosinophils/HPF. The median of the arithmetic means of the duodenal eosinophils counts per high power field were compared between H. pylori positive and H. pylori negative subjects. The relationship between the number of duodenal eosinophils and the intensity and type of dyspeptic symptoms was determined by validated questionnaire (PADYQ). Duodenal eosinophils counts were also evaluated by demographic variables and endoscopic findings. Results: 88% of the subjects were female and the mean age was 41.7 years. Baseline characteristics were similar between H. pylori positive and H. pylori negative subjects. Only one patient, in the H. pylori positive group, had duodenal eosinophilia. The median duodenal eosinophils/HPF were 4.6 [Percentiles 25-75(P25-75): 2.8-7.2] in H. pylori negative and 4.7 [P25-75: 3.4-8.4] in H. pylori positive subjects (p= 0.403). The duodenal eosinophil count was greater in subjects with higher symptoms severity: patients with PADYQ score more than 22 (>50% of the maximum score) had median duodenal eosinophil/HPF of 5.4 [P25-75: 3,4–7,6] and subjects with PADYQ score ≤22 of 3.4 [P25-75: 2.2–6.0] (p= 0.018). The patients were divided into terciles, according to symptoms severity: group 1 with 31 subjects (mild symptoms); group 2 with 30 subjects (moderate symptoms); and group 3 with 31 subjects (severe symptoms). 10 The median duodenal eosinophils/HPF was 3.4 [P25-75: 2.2-6.0] in group 1; 4.7 [P25-75: 3.2-6.4] in group 2; and 5.8 [P25-75: 3.6-8.2] in group 3 (p=0.033). There was a higher duodenal eosinophils count in smokers (current or former) (p=0.030), and subjects with BMI ≥ 25 kg/m2 (p=0.035). In the multivariate analysis by linear regression, the duodenal eosinophil count were influenced by smoking (p = 0.026) and dyspeptic symptoms severity (p= 0.039). Conclusion: This study did not show an association between H. pylori infection and the number of duodenal eosinophils, in this population of functional dyspeptic patients. However, a directly proportional and statistically significant relationship between the number of duodenal eosinophils and the intensity of dyspeptic symptoms has been demonstrated.
36

Eosinófilos duodenais : potencial associação com a infecção pelo Helicobacter pylori e com os sintomas da dispepsia funcional

Mazzoleni, Felipe January 2017 (has links)
Introdução e objetivos: Eosinofilia duodenal está associada com parasitoses intestinais e com alergias alimentares, e tem sido sugerida como possível fator etiológico da dispepsia funcional, pela capacidade de causar alterações na motilidade e na sensibilidade do aparelho digestivo. Sua relação com o Helicobacter pylori é pouco conhecida, tendo sido avaliada apenas como achado secundário em alguns estudos, com resultados controversos. Esse estudo tem como objetivos avaliar o papel da infecção gástrica pelo H. pylori no número de eosinófilos duodenais e avaliar a relação dos eosinófilos duodenais com os sintomas da dispepsia funcional. Métodos: foram avaliados 100 pacientes dispépticos funcionais, de acordo com os critérios de Roma III, dos quais 50 foram H. pylori positivos e 50 negativos. Os pacientes foram submetidos à endoscopia digestiva alta com biópsias gástricas e duodenais. A positividade do H. pylori foi avaliada pelo teste de urease e pelo exame histológico (Hematoxilina-eosina e Giemsa). As biópsias duodenais foram avaliadas com hematoxilina-eosina e a número de eosinófilos duodenais foi quantificada pela média de eosinófilos por 5 campos de grande aumento (CGA) aleatórios e não sobrepostos. Eosinofilia duodenal foi definida pela presença de >22 eosinófilos/CGA. As medianas das médias aritméticas dos eosinófilos duodenais por cinco CGA foram comparadas entre os pacientes H. pylori positivos e negativos. Também foi avaliada a relação do número de eosinófilos duodenais com a intensidade e tipo de sintomas dispépticos, determinados por questionário validado (PADYQ). Os eosinófilos duodenais foram avaliados para variáveis demográficas e endoscópicas. Resultados: Pacientes do sexo feminino representaram 88% da amostra e a idade média foi de 41,7 anos As características basais dos pacientes H. pylori positivos e H. pylori negativos foram semelhantes. Apenas um paciente, no grupo H. pylori positivo, apresentou eosinofilia duodenal. As medianas dos eosinófilos duodenais/CGA foram 4,6 [P25-75: 2,8-7,2] nos pacientes H. pylori negativos e 4,7 [P25-75: 3,4-8,4] nos H. pylori positivos (p= 0,403). O número de eosinófilos 8 duodenais foi significativamente maior em pacientes com sintomas mais intensos: pacientes com escore do PADYQ >22 (>50% da pontuação máxima) apresentaram mediana de eosinófilos duodenais/CGA de 5,4 [P25-75: 3,4–7,6] e pacientes com escore ≤22 de 3,4 [P25-75: 2,2–6,0] (p= 0,018). Os pacientes foram divididos em tercis, de acordo com a intensidade dos sintomas: grupo 1 com 31 pacientes (sintomas leves); grupo 2 com 30 pacientes (sintomas moderados); e grupo 3 com 31 pacientes (sintomas acentuados). A mediana dos eosinófilos duodenais/CGA no grupo 1 foi de 3,4 [P25-75: 2,2 -6,0]; no grupo 2 de 4,7 [P25-75: 3,2-6,4]; e o grupo 3 de 5,8 [P25-75: 3,6-8,2] (P=0,033). Houve diferença estatisticamente significativa no número de eosinófilos duodenais entre fumantes e não fumantes (p= 0,030) e entre pacientes com índice de massa corporal (IMC) <25 kg/m2 e IMC ≥ 25 kg/m2 (p= 0,035). Na análise multivariada por regressão linear, os fatores que tiveram influência sobre o número de eosinófilos duodenais foram o tabagismo (p= 0,026) e a intensidade dos sintomas dispépticos (p= 0,039). Conclusões: Esse estudo não mostrou associação entre a infecção pelo H. pylori e a contagem de eosinófilos duodenais, nessa população de pacientes dispépticos funcionais. Entretanto, foi demonstrada uma relação diretamente proporcional e estatisticamente significativa entre o número de eosinófilos duodenais e a intensidade dos sintomas dispépticos. / Background and Aims: Duodenal eosinophilia is associated with intestinal parasitosis and food allergies. It has also been implicated as a potential factor on the etiology of functional dyspepsia, probably by causing changes in digestive tract motility and sensitivity. The association with Helicobacter pylori is poorly understood, and has been only evaluated as a secondary finding in 9 previous studies, with conflicting results. This study aims to evaluate the potential role of gastric H. pylori infection in the duodenal eosinophil count, and the influence of duodenal eosinophils on symptoms in functional dyspeptic subjects. Methods: One hundred functional dyspeptic subjects, according to Rome III criteria, were evaluated, and 50 were H. pylori positive and 50 H. pylori negative. Patients were submitted to upper gastrointestinal endoscopy with gastric and duodenal biopsies. H. pylori positivity was evaluated by urease test and gastric histology (Hematoxylin-eosin and Giemsa). Duodenal biopsies were evaluated with Hematoxylin-Eosin staining, and the duodenal eosinophil count was determined by the mean of eosinophil by 5 random nonoverlapping high power fields (HPF). Duodenal eosinophilia was defined as >22 eosinophils/HPF. The median of the arithmetic means of the duodenal eosinophils counts per high power field were compared between H. pylori positive and H. pylori negative subjects. The relationship between the number of duodenal eosinophils and the intensity and type of dyspeptic symptoms was determined by validated questionnaire (PADYQ). Duodenal eosinophils counts were also evaluated by demographic variables and endoscopic findings. Results: 88% of the subjects were female and the mean age was 41.7 years. Baseline characteristics were similar between H. pylori positive and H. pylori negative subjects. Only one patient, in the H. pylori positive group, had duodenal eosinophilia. The median duodenal eosinophils/HPF were 4.6 [Percentiles 25-75(P25-75): 2.8-7.2] in H. pylori negative and 4.7 [P25-75: 3.4-8.4] in H. pylori positive subjects (p= 0.403). The duodenal eosinophil count was greater in subjects with higher symptoms severity: patients with PADYQ score more than 22 (>50% of the maximum score) had median duodenal eosinophil/HPF of 5.4 [P25-75: 3,4–7,6] and subjects with PADYQ score ≤22 of 3.4 [P25-75: 2.2–6.0] (p= 0.018). The patients were divided into terciles, according to symptoms severity: group 1 with 31 subjects (mild symptoms); group 2 with 30 subjects (moderate symptoms); and group 3 with 31 subjects (severe symptoms). 10 The median duodenal eosinophils/HPF was 3.4 [P25-75: 2.2-6.0] in group 1; 4.7 [P25-75: 3.2-6.4] in group 2; and 5.8 [P25-75: 3.6-8.2] in group 3 (p=0.033). There was a higher duodenal eosinophils count in smokers (current or former) (p=0.030), and subjects with BMI ≥ 25 kg/m2 (p=0.035). In the multivariate analysis by linear regression, the duodenal eosinophil count were influenced by smoking (p = 0.026) and dyspeptic symptoms severity (p= 0.039). Conclusion: This study did not show an association between H. pylori infection and the number of duodenal eosinophils, in this population of functional dyspeptic patients. However, a directly proportional and statistically significant relationship between the number of duodenal eosinophils and the intensity of dyspeptic symptoms has been demonstrated.
37

The Eosinophil and Lysophospholipase Responses in Mice Infected with Trichinella spiralis: A Role for the Lymphocyte and Macrophage

Adewusi, Iyabode Olukemi, 1958- 08 1900 (has links)
The relationship among eosinophils, lysophospholipase activity and the immune response in animals infected with Trichinella spiralis was studied using in vivo and in vitro techniques. In an in vivo experiment, anti-thymocyte serum (ATS) was administered to mice infected with T. spiralis and its effects on intestinal lysophospholipase (EC 3.1.1.5.) activity, peripheral blood, bone marrow and intestinal eosinophilia were measured in the same experimental animal. The ATS caused a significant temporally related suppression of both the tissue lysophospholipase response and eosinophilia, in all three compartments. These findings support the hypothesis that parasite-induced eosinophilia is the cause of the increased lysophospholipase activity of parasitized tissue and that the responses are thymus cell-dependent. In vitro experiments demonstrated that the eosinophil was the primary inflammatory cell source of lysophospholipase among eosinophils, neutrophils macrophages and lymphocytes. The role of other cells and antigen in the production of the enzyme by the eosinophil was also investigated in vitro• Results demonstrated that eosinophils cultured with both T. spiralis antigen and other leukocytes yielded enzyme activities significantly greater than eosinophils cultured alone or with only antigen. More specific experiments showed that T-lymphocytes were the cells responsible for influencing the eosinophils' lysophospholipase activity in the presence of antigen, and that their influence was enhanced by the presence of macrophages. These results suggested that increased lysophospholipase activity present in parasitized tissue was not only due to increased numbers of eosinophils infiltrating parasitized tissue but was also due to each eosinophil synthesizing more of the enzyme. The necessity for antigen and other cells suggests a role for cell cooperation in the production of the enzyme, specifically T-lymphocytes and macrophage interaction with the eosinophil. A lymphocyte soluble factor collected from sensitized lymphocytes stimulated with specific antigen or concanavalin A was found to enhance the eosinophil lysophospholipase activity when added to cultures of eosinophils plus other peritoneal cells. The soluble factor did not stimulate the lysophospholipase activity of pure cultures of eosinophils.
38

Vasculites e lesões isquêmicas imunomediadas como fatores preditores de mau prognóstico no transplante cardíaco / Imuno mediated vasculitis and ischemia as predictor factors of bad prognosis in cardiac transplantation

Cipullo, Reginaldo 23 September 2010 (has links)
INTRODUÇÃO: O significado clínico das vasculites, lesões isquêmicas, efeito Quilty e da presença de eosinófilos em biópsias endomiocardicas de receptores de transplante cardíaco com rejeições leves não foi ainda estabelecido. OBJETIVOS: Verificar se estes achados histológicos encontrados nas biópsias endomiocardicas (eosinófilos, vasculites, efeito Quilty e lesões isquêmicas) são capazes de predizer rejeição aguda do enxerto acompanhada ou não de grave comprometimento hemodinâmico e morte por rejeição aguda. MÉTODOS: Foram reavaliadas 939 biópsias endomiocardicas consecutivas classificadas como OR ou 1R pela de 2005 da Nomenclatura da Sociedade Internacional de Transplante de Coração e Pulmão e dividimos estas em dois grupos (1) Biópsias preditoras: aquelas que precederam rejeição aguda, rejeição aguda associada à grave comprometimento hemodinâmico ou morte e (2) Biópsias não preditoras aquelas que não precederam eventos clínicos. Comparamos a ocorrência dos seguintes achados histológicos: vasculites, lesões isquêmicas, efeito Quilty e eosinófilos por análise uni e multivariada entre os grupos. RESULTADOS: Após análise estatística verificou-se que a presença de vasculite intensa e de eosinófilos como maiores preditores tanto para rejeição aguda futura, apresentando respectivamente as seguintes razões de chance: 10,60 (IC95%: 3,62 31,06. p<0,001) e 6,26 (IC95%:3,16 12,43. p< 0,001) , quanto para rejeição aguda associada á grave comprometimento hemodinâmico, que para este desfecho clínico apresentaram respectivamente as seguintes razões de chance 7,52 (IC95%: 1,45-38,93. p=0,016) e 6,61 (IC95%: 2,38 18,31. p< 0,001), e também para morte em decorrência a rejeição aguda com as respectivas razões de chance: 11,20 (IC95%: 3,53 36,17. p < 0, 001) e 14,50 (IC95%: 2,19 36,17. p = 0,006). CONCLUSÕES: Vasculites intensas e eosinófilos em biópsias do miocárdio são os principais fatores preditores de rejeição aguda, rejeição aguda associada à grave comprometimento hemodinâmico e morte pós - transplante cardíaco / INTRODUCTION: The clinical meaning of vasculitis, ischemic lesions, Quilty effect and the presence of eosinophils in endomyocardial biopsies of transplant recipients with mild rejections have not been established yet. OBJECTIVES: Verify if these histological findings (eosinophils, vasculitis, Quilty effect and ischemic lesions), whose clinical meaning remains unknown so far, are able to predict acute rejection of the transplanted organ, accompanied or not by severe hemodynamic compromise and death due to acute rejection. METHODS: We reevaluated 939 consecutive endomyocardial biopsies classified as 0R or 1R, according to the nomenclature that the International Society for Heart and Lung Transplantation established in 2005. We divided these biopsies in 2 groups, as they follow: (1) Predictor biopsies, which are preceded by acute rejection, acute rejection associated to severe hemodynamic compromise or death and (2) Non-predictor biopsies that did not precede any clinical events. We compared the occurrence of the histological findings studied (eosinophils, vasculitis, Quilty effect and ischemic lesions) through univariate and multivariate analysis among the groups. RESULTS: After an appropriate statistical analysis, the result obtained was the presence of intense vasculitis and eosinophils as the greatest predictors of future acute rejection, presenting the respective odds ratio: 10,60 (IC95%: 3,62 31,06. p<0,001) and 6,26 (IC95%:3,16 12,43. p< 0,001), as well as acute rejection associated to severe hemodynamic compromise, which presented the respective odds ratio for this clinical outcome: 7,52 (IC95%: 1,45-38,93. p=0,016) and 6,61 (IC95%: 2,38 18,31. p< 0,001) and death due to acute rejection, presenting the respective odds ratio: 11,20 (IC95%: 3,53 36,17. p < 0, 001) and 14,50 (IC95%: 2,19 36,17. p = 0,006). CONCLUSIONS: Intense vasculitis and eosinophils in myocardial biopsies post-cardiac transplantation are the chief factors that can predict acute rejection, acute rejection associated to severe hemodynamic compromise or death
39

Eosinophils and eosinophilic chemokines in asthma and the effect of inhaled corticosteroids

Feltis, Bryce Nathan, 1975- January 2003 (has links)
Abstract not available
40

The biological mechanisms in neutrophil and eosinophil adhesion and transmigration in vitro and their relation to the inflammatory process in vivo /

Moshfegh, Ali , January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 5 uppsatser.

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