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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Cellular mechanism for regulation of ion transport in human bronchial epithelial cells by Cordyceps militaris extract and its isolated compound cordycepin.

January 2011 (has links)
Fung, Chun Kit. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 121-135). / Abstracts in English and Chinese. / Declaration --- p.i / Acknowledgement --- p.ii / Abbreviations --- p.iii / Abstract in English --- p.v / Abstract in Chinese --- p.vii / Table of Contents --- p.ix / List of Figures --- p.xii / Chapter Chapter 1 - --- Introduction / Chapter 1.1 --- Genus Cordyceps --- p.1 / Chapter 1.2 --- Cordyceps militaris --- p.4 / Chapter 1.3 --- Biological Functions and Chemical Constituents of Cordyceps militaris --- p.9 / Chapter 1.4 --- "Human Bronchial Epithelial Cell Line, 16HBE14o-" --- p.13 / Chapter 1.5 --- Ion Transport in Human Bronchial Epithelial Cells --- p.16 / Chapter 1.6 --- Objectives of the Experiments --- p.20 / Chapter Chapter 2 - --- Materials and Methods / Chapter 2.1 --- Solutions and Chemicals --- p.21 / Chapter 2.2 --- Preparation of Hot Water Cordyceps militaris Extract --- p.22 / Chapter 2.3 --- Culture of Cells --- p.23 / Chapter 2.4 --- Short-Circuit Current (lsc) Measurement --- p.24 / Chapter 2.5 --- Short-Circuit Current (lsc) Measurement in Nystatin-Permeabilized Monolayer --- p.29 / Chapter 2.6 --- Measurements of [Ca2+]i --- p.31 / Chapter 2.7 --- Measurement of PKA Activity --- p.36 / Chapter 2.8 --- Statistical Analysis --- p.37 / Chapter Chapter 3 - --- Results / Chapter 3.1 --- Regulation of Ion Transport in 16HBE14o- Cells by CM Water Extract --- p.38 / Chapter 3.1.1 --- Dose-Dependent Relationship of CM Water Extract --- p.39 / Chapter 3.1.2 --- "Involvement of CI"" Transport in CM-induced lsc Response" --- p.42 / Chapter 3.1.3 --- Involvement of K+ channels in CM-induced lsc Response --- p.47 / Chapter 3.1.4 --- Involvement of Adenylate Cyclase/cAMP/Protein Kinase A Pathway in CM-induced lsc Response --- p.52 / Chapter 3.1.5 --- Involvement of Ca2+-Dependent Pathway in CM-induced lsc Response --- p.57 / Chapter 3.1.6 --- "Effect of CM Extract on Apical CI"" Current and Basolateral K+ Current in Nystatin-Permeabilized Epithelia" --- p.61 / Chapter 3.1.7 --- Effect of CM Extract on PKA Activity --- p.67 / Chapter 3.2 --- Regulation of Ion Transport in 16HBE14o- Cells by Cordycepin --- p.70 / Chapter 3.2.1 --- Dose-Dependent Relationship of Cordycepin --- p.70 / Chapter 3.2.2 --- "Involvement of CI"" Transport in Cordycepin-induced lsc Response" --- p.73 / Chapter 3.2.3 --- Involvement of K+ channels in Cordycepin-induced lsc Response --- p.79 / Chapter 3.2.4 --- Involvement of Adenylate Cyclase/cAMP/Protein Kinase A Pathway in Cordycepin-induced lsc Response --- p.84 / Chapter 3.2.5 --- Involvement of Ca2+-Dependent Pathway in Cordycepin-induced lsc Response --- p.89 / Chapter 3.2.6 --- Effect of Cordycepin on Intracellular Ca2+ Concentrations --- p.93 / Chapter 3.2.7 --- "Effect of Cordycepin on Apical CI"" Current and Basolateral K+ Current in Nystatin-Permeabilized Epithelia" --- p.98 / Chapter 3.2.8 --- Effect of Cordycepin on PKA Activity --- p.104 / Chapter Chapter 4 - --- Discussion / Chapter 4.1 --- Regulation of Ion Transport in 16HBE14o- Cells by CM Extract --- p.107 / Chapter 4.2 --- Intracellular Signaling Mechanisms behind CM-induced lsc Responses --- p.110 / Chapter 4.3 --- Regulation of Ion Transport in 16HBE14o- Cells by Cordycepin --- p.111 / Chapter 4.4 --- Intracellular Signaling Mechanisms behind Cordycepin-induced lsc Responses --- p.114 / Chapter Chapter 5 - --- Conclusion / Chapter 5.1 --- Summary --- p.117 / Chapter 5.2 --- Future Directions --- p.120 / Chapter Chapter 6 - --- References --- p.121 / Chapter Chapter 7 - --- Publications --- p.136
22

Regulation of chloride secretion by P2Y receptors in polarized human bronchial epithelia, 16HBE14o-.

January 2007 (has links)
Wong, Miu Fong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 140-152). / Abstracts in English and Chinese. / DECLARATION --- p.i / ACKNOWLEDGEMENT --- p.ii / ABBREVIATIONS --- p.iii / ABSTRACT IN ENGLISH --- p.iv / ABSTRACT IN CHINESE --- p.vii / TABLE OF CONTENTS --- p.ix / LIST OF FIGURES --- p.xii / LIST OF TABLES --- p.xviii / Chapter CHAPTER I - --- INTRODUCTION / Chapter 1.1 --- Regulation of human airway surface liquid --- p.1 / Chapter 1.2 --- Sodium reabsorption and chloride secretion in airway epithelium --- p.3 / Chapter 1.3 --- Purinergic receptors --- p.7 / Chapter 1.4 --- P2Y receptors in epithelial cells --- p.11 / Chapter 1.5 --- Autocrine or paracrine regulation of ion transport in epithelial cells --- p.13 / Chapter 1.6 --- Signaling pathways underlying the regulation of ion transport by P2Y receptors stimulation --- p.16 / Chapter 1.7 --- The therapeutic potential of P2Y receptors in treating cystic fibrosis --- p.18 / Chapter 1.8 --- Particular interest on P2Y6 receptor as potential target for treatment of cystic fibrosis --- p.21 / Chapter 1.9 --- Properties of 16HBE14o- cell line --- p.23 / Chapter 1.10 --- Objectives of the present experiments --- p.25 / Chapter CHAPTER II - --- MATERIALS AND METHODS / Chapter 2.1 --- Solutions and Chemicals --- p.26 / Chapter 2.2 --- Cell culture --- p.28 / Chapter 2.3 --- Simultaneous measurement of short-circuit current (Isc) and intracellular calcium concentration ([Ca2+ ])i --- p.29 / Chapter 2.3.1 --- Preparation of 16HBE14o- cells for simultaneous measurement of Isc and [Ca2+]i --- p.29 / Chapter 2.3.2 --- Measurement of Isc and transepithelial resistance with Ussing chamber --- p.32 / Chapter 2.3.3 --- Simultaneous measurement of Isc and [Ca2+]i --- p.35 / Chapter 2.4 --- Measurement of protein kinase A activity --- p.38 / Chapter 2.5 --- Data analysis --- p.39 / Chapter CHAPTER III - --- RESULTS / Chapter 3.1 --- Apical and basolateral application of P2Y agonists induced Isc and [Ca2+]i responses in 16HBE14o- cells --- p.40 / Chapter 3.1.1 --- Effect of apical and basolateral application of ATP on Isc and [Ca2+̐]ư --- p.40 / Chapter 3.1.2 --- Effect of apical and basolateral application of UTP on Isc and [Ca2+̐]ư --- p.45 / Chapter 3.1.3 --- Effect of apical and basolateral application of UDP on Isc and [Ca2+̐]ư --- p.50 / Chapter 3.1.4 --- "Summary of the effects of apical and basolateral application of ATP, UTP and UDP on Isc and [Ca2+̐]ư" --- p.55 / Chapter 3.2 --- Ionic mechanisms underlying the effect of apical and basolateral UDP on 16HBE14o- cells --- p.56 / Chapter 3.2.1 --- Differential effect of apical and basolateral UDP on Isc --- p.56 / Chapter 3.2.2 --- Effect of various apical CI- channel blockers on Isc response induced by apical and basolateral application of UDP --- p.59 / Chapter 3.2.3 --- Effect of various basolateral K+ channel blockers on Isc response induced by apical and basolateral application of UDP --- p.83 / Chapter 3.3 --- Involvement of other signaling molecules or pathways in regulation of the chloride secreting response evoked by apical and basolateral UDP --- p.108 / Chapter 3.3.1 --- Effect of apical and basolateral UDP on PKA activity --- p.109 / Chapter 3.3.2 --- Effect of PKC inhibitors on Isc response induced by apical and basolateral application of UDP --- p.111 / Chapter CHAPTER IV - --- DISCUSSION / Chapter 4.1 --- Simultaneous measurement of Isc and [Ca2+ ̐]ư upon apical and basolateral application of P2Y agonists in 16HBE14o- cells --- p.125 / Chapter 4.2 --- Ionic mechanism underlying the effect of apical and basolateral UDP on 16HBE14o- cells --- p.128 / Chapter 4.2.1 --- Possible ionic mechanism for chloride secretion mediated by apical P2Y6 receptors --- p.131 / Chapter 4.2.2 --- Possible ionic mechanism for chloride secretion mediated by basolateral P2Y6 receptors --- p.133 / Chapter 4.3 --- Involvement of other possible signaling molecules or pathway underlying the action of apical and basolateral UDP --- p.135 / Chapter 4.4 --- Summary --- p.138 / Chapter CHAPTER V - --- REFERENCES --- p.140 / Publications --- p.153
23

Analyse et méta-analyse des niveaux d'expression d'GF-R, c-erbB-2, Ki-67 et des micro-vaisseaux aux différents stades de développement des cancers bronchiques

Meert, Anne-Pascale 28 March 2007 (has links)
Dans un premier temps, nous avons réalisé des revues systématiques de la littérature avec méta-analyses des données de survie. Ceci nous a conduits à sélectionner 4 marqueurs de mauvais pronostic pour la survie des CBNPC: le récepteur au facteur de croissance épidermique (EGF-R), un autre récepteur de cette famille (c-erbB-2) ainsi que deux autres facteurs potentiellement témoins de leur activité, Ki-67 (impliqué dans la prolifération) et le nombre des micro-vaisseaux (témoins de la néoangiogenèse).<p>Dans une deuxième phase, nous avons étudié au laboratoire diverses questions sur des tumeurs bronchiques invasives.<p>Premièrement, nous avons investigué le mécanisme de surexpression d’EGF-R et de c-erbB-2 et évalué si des anomalies génétiques pouvaient prédire cette surexpression, en recourant à des techniques d’immunohistochimie et de FISH. Ceci nous a permis d’observer que, si la majorité des CBNPC réséqués présentent des anomalies génétiques d’EGF-R et/ou de c-erbB-2, une amplification de ces gènes n’est présente que dans une minorité d’entre eux et n’est pas strictement corrélée à l’expression protéique. D’autre part, la survie de ces patients exprimant ou ayant une anomalie génique d’EGF-R et/ou c-erbB-2 est plus courte sans atteindre le seuil de signification statistique.<p>Deuxièmement, nous avons recherché sur des tumeurs opérées d’éventuels liens entre les expressions d’EGF-R, de c-erbB-2 et de Ki-67. Aucune corrélation n’a été mise en évidence entre l’expression de ces 3 facteurs. Par contre, chez ces patients, l’expression de Ki-67 dans la tumeur s’est avérée être un facteur de mauvais pronostic pour la survie.<p>Troisièmement, nous avons voulu savoir si un de ces marqueurs (EGF-R) présentait une valeur pronostique dans un groupe plus restreint de tumeurs plus avancées, les CBNPC de stade III. Pour mener cette recherche sur des biopsies, nous avons d’abord démontré que l’évaluation des marqueurs biologiques (EGF-R, c-erbB-2 et Ki-67) sur biopsie ne différait pas de celle réalisée sur des tumeurs réséquées. Comme les résultats étaient équivalents, nous avons pu étudier EGF-R sur les biopsies de CBNPC au stade III et montrer qu’EGF-R n’était pas un facteur pronostique pour la survie dans ce groupe assez homogène de tumeurs avancées.<p>Dans la dernière phase, nous avons étudié des lésions représentatives des différents stades prénéoplasiques et néoplasiques précoces radiooccultes. Ces lésions ont été prélevées lors d’examens endoscopiques de photodétection. EGF-R, c-erbB-2, Ki-67 et le nombre des micro-vaisseaux ont été étudiés par immunohistochimie dans ces différents stades de lésions prénéoplasiques et néoplasiques précoces. Nous avons observé qu’EGF-R et Ki-67 sont statistiquement plus exprimés dans les dysplasies sévères et les carcinomes in que dans les dysplasies légères suggérant que, au moins pour ces 2 marqueurs, les dysplasies sévères se rapprochent plus des carcinomes in situ que des dysplasies légères. Alors que l’expression d’EGF-R est présente dès le stade de dysplasie sévère, une augmentation du nombre des micro-vaisseaux n’est présente qu’au stade de tumeurs micro-invasives. C-erbB-2 n’est quant à lui pas exprimé dans ces lésions bronchiques prénéoplasiques et néoplasiques précoces. <p>En conclusion, les facteurs biologiques, EGF-R, c-erbB-2 et Ki-67 et le nombre des micro-vaisseaux s’avèrent des facteurs de mauvais pronostic dans le CBNPC. La surexpression d’EGF-R et de c-erbB-2 dans les cancers réséqués résulte très rarement d’une amplification génique et nous n’avons pas trouvé dans ces tumeurs de corrélation entre l’expression des marqueurs moléculaires étudiés. Dans les tumeurs plus avancées de stade III, EGF-R n’est pas un facteur discriminant pour le pronostic. Les anomalies de certains de ces marqueurs (EGF-R et Ki-67) apparaissent précocement, dès les stades prénéoplasiques, avec un seuil se situant entre les lésions bronchiques de bas et de haut grades. La néoangiogénèse, évaluée par le nombre des micro-vaisseaux, s’observe à partir des cancers micro-invasifs tandis que c-erbB-2 n’apparaît qu’au stade invasif. Dans la séquence d’apparition des anomalies génétiques conduisant au cancer invasif, l’atteinte d’EGF-R précède la néoangiogénèse.<p> / Doctorat en sciences médicales / info:eu-repo/semantics/nonPublished
24

Expression of G protein-coupled estrogen receptor (GPER) and its effects on P2Y receptor-mediated Ca²⁺ signalling and cytokine secretion in human bronchial epithelia / CUHK electronic theses & dissertations collection

January 2014 (has links)
The airway epithelium plays a central role in respiratory physiology through its transport and immunological functions. Our previous study suggested that P2Y receptors are expressed in airway epithelia and play a significant role in regulating transepithelial ion transport. P2Y receptors belong to the family of purinergic receptors, which can be stimulated by nucleotides such as UTP and UDP. P2Y receptors are G protein-coupled receptors and classically signal through G[subscript q], resulting in an increase in intracellular Ca²⁺ concentration ([Ca²⁺]ᵢ) and thereby in the activation of Ca²⁺-dependent ion channels and downstream signalling pathway(s). Furthermore, P2Y receptors are involved in asthmatic inflammation. / Estrogen (or E₂) is an important hormone in human physiology. In addition to the classical nuclear hormone receptors ERα and ERβ, a novel estrogen receptor, G protein-coupled estrogen receptor (GPER), was recently identified and found to be involved in both rapid signalling and transcriptional regulations. The action of GPER is unclear, but it has been implicated in mediating anti-inflammatory responses. / In our experiments, both human bronchial epithelial cell line, 16HBE14o-, and primary normal human bronchial epithelial cells expressed GPER at mRNA and protein levels, as demonstrated by RT-PCR and western blotting, respectively. ERα and ERβ expression were also detected at mRNA and protein level. Expression of GPER receptors was localized in the human bronchial epithelial cells by immunofluorescence staining and western blotting of fractionated cell lysates. / [Ca²⁺]ᵢ induced by nucleotides were monitored by calcium imaging technique using MetaFluor fluorescence ratio imaging system. Stimulation of epithelial cells with E₂ or with the specific agonist of GPER, G1, rapidly attenuated a UDP-, UTP- or ATPyS- evoked increase in [Ca²⁺]ᵢ in both 16HBE14o- cell line and primary cells. This inhibitory effect of E₂ and G1 were concentration dependent, while this effect was reversed by GPER specific antagonist, G15. To examine the effect of E₂ and G1 on UDP-activated intracellular Ca²⁺ release and influx, the epithelia were exposed to nominally Ca²⁺ -free solution in the presence or absence of G1 or E₂, and then stimulated with UDP. Subsequently, Ca²⁺ was added to the perfusate. Both E₂ and G1 could inhibit UDP-induced Ca²⁺ release. However, only E₂ but not G1 could inhibit UDP-induced Ca²⁺ influx. / E₂ or G1 inhibited the secretion of two pro-inflammatory cytokines, interleukin (IL)-6 or IL-8, in cells stimulated by different nucleotides or the cationic protein, poly-L-arginie, as quantified by ELISA. CFP-Epac-YPF, an Epac-based polypeptide FRET reporter was used to monitor the real-time cAMP changes in 16HBE14o- cells. Both G1 and E₂ induced an increase in cAMP production. The transepithelial chloride (Cl⁻) secretion was measured using short circuit current technique in cells grown on permeable support. Cl⁻ secretion induced by apical UDP was partially inhibited by G1 in a concentration dependent manner. / Our results provide the first evidence that human bronchial epithelia express GPER, which interact with the P2Y receptor-mediated calcium signalling pathway and cytokine secretion. Moreover, the anti-inflammatory role of GPER may be due to its opposing effect on the pro-inflammatory pathway activated by the P2Y receptors in inflamed airway epithelia. / 气道上皮具有调节运输以及参与免疫反应等功能,在呼吸生理学研究中有着十分关键的意义。我们曾经的研究发现P2Y受体在气道上皮中表达并调节上皮细胞离子运输过程。P2Y受体属于嘌呤受体,可被三磷酸尿苷(UTP),二磷酸尿苷(UDP)等核苷酸激活。同时,P2Y受体也是一类G蛋白偶联受体,可通过活化G[subscript q]蛋白调控细胞内钙离子浓度而激活钙依赖性离子通道及其他下游信号通路。此外P2Y受体还参与哮喘炎症的调控。 / 雌激素(或雌二醇,E₂)是人体一类十分重要的激素。除传统的核受体ERα与ERβ外,一类新型雌激素受体GPER已被发现和鉴定。GPER属于G蛋白偶联受体,可同时参与转录调控和非基因依赖的快速信号调节。尽管具体机理尚不明确,但研究发现GPER可介导抗炎症反应。 / 实验结果显示,在支气管上皮细胞株16HBE14o-和原代人支气管上皮细胞中GPER都被检测到基因和蛋白水平的表达。GPER在人支气管上皮细胞中的定位也通过免疫荧光染色(immunofluorescence)和亚细胞组分蛋白质印迹(western blot of fractionated cells)得到鉴定。 / 本研究中,荧光显微技术(fluorescence microscopy)被用于测定核苷酸介导的细胞内钙离子浓度([Ca²⁺]ᵢ)。在16HBE14o- 和原代培养人支气管上皮细胞中,E₂和GPER特异性激动剂G1都可抑制核苷酸介导的 [Ca²⁺]ᵢ增加,且这种抑制作用呈浓度依赖。GPER特异性拮抗剂G15可抵消G1的抑制作用。进一步研究表明,E₂和G1都可抑制UTP诱导的胞内钙库释放,然而只有E₂抑制UTP诱导的胞外钙离子内流。 / 除钙离子调节外,E₂和G1还可抑制支气管上皮细胞中核苷酸或聚精氨酸(poly-L-arginine)刺激介导的两种促炎症细胞因子,白介素6(IL-6)和白介素8(IL-8)的分泌。酶联免疫法(ELISA)被用于细胞因子的定量。同时,CFP-Epac-YPF作为一类多肽荧光共振能量转移(FRET)探针被转染入16HBE14o- ,探测细胞内腺苷-3',5'-环化一磷酸(cAMP)的实时变化。结果显示在人支气管上皮细胞中E₂和G1都可引导cAMP生成。此外,我们使用短路电流(short-circuit current, Isc)技术测定单层上皮细胞的氯离子(Cl⁻)分泌,并发现人支气管上皮顶膜面UDP诱导的Cl⁻ 分泌可被G1部分抑制,且抑制效果呈浓度依赖。 / 本研究首次证明GPER表达于人支气管上皮, 且激活GPER对P2Y受体介导的钙离子信号通路以及细胞因子生成起到抑制作用。这些结果表明在气道炎症反应中,GPER可通过反向调节P2Y受体激活的促炎症作用,达到抗炎症的效果。 / Hao, Yuan. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 187-211). / Abstracts also in Chinese. / Title from PDF title page (viewed on 03, November, 2016). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.
25

Intracellular signal transduction mechanisms regulating the activation of human bronchial epithelial cells by interleukin-17A, interleukin-27, tumor necrosis factor-alpha and human basophils in inflammatory diseases. / CUHK electronic theses & dissertations collection

January 2010 (has links)
Airway bronchial epithelial cells play important roles in host defense, inflammation and regulation of immune responses. Activated bronchial epithelial cells are potent sources of a wide variety of soluble and cell-surface molecules that can alter the biological functions of inflammatory cells in the airways. Molecular mechanisms regulating the production of inflammatory mediators from bronchial epithelial cells remain to be fully elucidated. / All of the above findings suggest that human bronchial epithelial cells could be activated by a variety of stimuli in airway inflammatory reactions. Besides, different intracellular signaling pathways could regulate the activation of human bronchial epithelial cells in response to different stimuli. Our results therefore provide new insight into the molecular mechanisms involved in airway inflammatory diseases and may have important therapeutic implications. / Basophils are the accessory cell type required for T helper (Th)2 induction and initiators in IgE-mediated chronic allergic inflammation in response to allergens. Number of basophils and Th17 cells increases at the sites of allergic inflammation in the airways of allergic asthmatic patients. To elucidate the interaction among the activation of human bronchial epithelial cells, Th17 cells, and basophils, we investigated the activation effects of Th17 hallmark cytokine IL-17A on the human primary bronchial epithelial cells/BEAS-2B bronchial epithelial cells and human primary basophils/ KU812 basophilic cells. Human bronchial epithelial cells and basophils were cultured either together or separately in the presence or absence of IL-17A stimulation. Co-culture of human bronchial epithelial cells and basophils could significantly increase the release of inflammatory cytokine IL-6 and mononuclear chemoattractant protein-1 (MCP-1/CCL2), a chemokine for basophils, eosinophils and monocytes, while human bronchial epithelial cells were the main source for releasing IL-6 and CCL2. Such induction was synergistically enhanced upon the activation of IL-17A. The use of transwell inserts in the co-culture system demonstrated that the direct interaction between these two cell types was necessary for IL-6 and CCL2 release induced by IL-17A. Surface expression of intercellular adhesion molecule-1 (ICAM-1) on the human bronchial epithelial cells was also up-regulated upon their interaction. The interaction of human bronchial epithelial cells and basophils under IL-17A stimulation was differentially regulated by extracellular signal-regulated kinase (ERK), c-Jun N-terminal protein kinase (JNK), p38 mitogen activated protein kinase (MAPK) and nuclear factor (NF)-kappaB pathways. Our findings therefore suggest a novel immunopathological role of human Th17 cells and basophils in allergic asthma through the activation of granulocytes-mediated inflammation initiated by the direct interaction between human basophils and bronchial epithelial cells. / IL-27 is a novel member of the IL-6/IL-12 family cytokines that are produced early by antigen-presenting cells (APCs) during immune responses. IL-27 can drive the commitment of naive T cells to a Th1 phenotype and inhibit inflammation in later phases of infection. Recent evidence has suggested that human bronchial epithelial cells with the expression of IL-27 receptor complex are potential target cells of IL-27. Here we investigated the in vitro effects of IL-27, alone or in combination with inflammatory cytokine TNF-alpha on the pro-inflammatory activation of human bronchial epithelial cells, and the underlying intracellular signaling molecules were also studied. IL-27 was found to up-regulate ICAM-1 expression on the surface of human bronchial epithelial cells, and a synergistic effect was observed in the combined treatment of IL-27 and TNF-alpha on the surface expression of ICAM-1. Although IL-27 did not alter the basal IL-6 secretion from human bronchial epithelial cells, it could significantly enhance TNF-alpha-induced IL-6 production. The synergistic effects on the induction of ICAM-1 and IL-6 were partially due to the up-regulated expression of TNF-alpha receptor (p55TNFR) on the surface of human bronchial epithelial cells induced by IL-27. Further investigations showed that the enhanced production of ICAM-1 and IL-6 in human bronchial epithelial cells activated by IL-27 and TNF-alpha was differentially regulated by phosphatidylinositol 3-OH kinase (PI3K)-Akt, p38 MAPK and NF-kappaB pathways. Our study therefore suggests a potential role of IL-27 and TNF-alpha in the pathogenesis of airway infection or inflammatory diseases. / In the present study, we investigated the mechanisms of the activation of human bronchial epithelial cells induced by various stimuli including interleukin (IL)-17A, IL-27, tumor necrosis factor (TNF)-alpha and human basophils. The activation of human bronchial epithelial cells was studied in terms of the expression of cytokines, chemokines and adhesion molecules. Using intracellular staining with flow cytometry and selective pharmacological inhibitors, we further investigated the underlying intracellular signaling mechanisms regulating the activation of human bronchial epithelial cells. / Cao, Ju. / Advisers: Chun K. Wong; Christopher W. K. Lam. / Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 175-202). / 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.
26

Estudo dos efeitos da prednisona sobre o sistema mucociliar de ratos / Effects of prednisone on mucociliary system of rats

Braga, Karina Andrighetti de Oliveira 03 November 2010 (has links)
INTRODUÇÃO: As infecções pulmonares constituem uma das principais causas de morbidade e mortalidade após o transplante pulmonar. O transplante expõe a árvore brônquica a uma série de condições, como à lesão de secção e anastomose brônquica e à ação dos imunossupressores, alterando os componentes do epitélio mucociliar. O sistema mucociliar presente nas vias aéreas do sistema respiratório é o principal mecanismo de defesa do trato respiratório, assim a influência de drogas neste sistema precisa ser investigada. A prednisona é um importante corticosteróide usado após o transplante de pulmão, no entanto seu uso pode estar associado ao aumento da mortalidade no período pós por complicações como baixa cicatrização e infecções. Desta forma, o objetivo deste estudo foi avaliar os efeitos da secção brônquica e da terapia com prednisona na depuração mucociliar. MÉTODOS: Foram utilizados 180 ratos machos Wistar distribuídos em 6 grupos (P1, P2, P3, ScP2, ScSal e Sal). Os animais dos grupos P1, P2 e P3 receberam diferentes doses de prednisona (0,625, 1,25 e 2,5 mg/kg/dia); os do grupo ScP2 foram submetidos à cirurgia de secção e anastomose brônquica e terapia com 1.25 mg/kg/dia de prednisona; do grupo ScSal foram submetidos à cirurgia de secção e anastomose brônquica e gavagem diária de solução fisiológica; por fim, os animais do grupo Sal receberam gavagem de solução fisiológica. Após o período de tratamento (7, 15 ou 30 dias), os animais foram sacrificados, e as medidas de freqüência de batimento ciliar (FBC), velocidade de transporte mucociliar (VTMC) e transportabilidade do muco (TM) coletadas. Para avaliar os efeitos da droga realizamos a análise estatística comparativa entre os grupos P1, P2, P3 e Sal. Para avaliar a possível interação da droga com o procedimento cirúrgico comparamos os grupos ScP2, ScSal e P2. RESULTADOS: A administração das diferentes doses de prednisona estudadas prejudicaram a TM e a dosagem mais alta (P3) diminuiu a VTMC. Os animais submetidos à secção e anastomose brônquica mostraram redução significativa de VTMC e FBC após 7 e 15 dias da cirurgia (p<0.001) Observamos a recuperação desses parâmetros após 30 dias do procedimento cirúrgico. A droga melhorou a TM dos animais submetidos à secção e anastomose brônquica (p<0,02). CONCLUSÕES: Altas dosagens de prednisona prejudicam a depuração mucociliar. A terapia com prednisona associada à cirurgia de secção e anastomose brônquica não altera a depuração mucociliar visto que, apesar de melhorar a transportabilidade do muco, a freqüência de batimento ciliar e a velocidade de transporte mucociliar não são influenciadas / INTRODUCTION: Infections have been and still are the major cause of morbidity and mortality after lung transplantation. Since mucociliary clearance (MCC) plays an important role on the human defense mechanism, the influence of drugs on MCC of patients submitted to lung transplantation must be examined. Prednisone is the most important corticosteroid used after lung transplantation. The aim of this study was to evaluate the effects of bronchial transection and prednisone therapy (P) on mucociliary clearance. METHODS: 180 rats were assigned to 6 groups (P1, P2, P3, ScSal, e Sal) according to surgical procedure or drug therapy: P1 (0.625mg/kg/day), P2 (1.25 mg/kg/day), P3 (2.5mg/kg/day), ScP2 (bronchial section and reanastomosis + 1.25 mg/kg/day ), Sal (saline solution 2ml/day) and ScSal (bronchial section + saline solution 2ml/day). After 7, 15 or 30 days they were killed and lungs were removed from thoracic cavity. Mucociliary transport velocity (MCTV), ciliary beting frequency (CBF) and mucus transportability (MT) were evaluated. RESULTS: The administration of different doses of prednisone studied harmed MT and the highest dosage (P3) decreased MCTV. FBC and MCTV was significantly impaired 7 and 15 days after bronchial transection and reanastomosis (p<0.001), but they showed a partial recovery on the 30th day after surgery procedure. Prednisone therapy improved MT after surgery procedure (p<0,02). CONCLUSION: High dosages of prednisone affect mucociliary clearance. The Prednisone therapy after section and reanastomosis surgery not affect mucociliary clearance since, despite improving MT, the CBF and MCTV are not influenced
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High performance computer simulated bronchoscopy with interactive navigation.

January 1998 (has links)
by Ping-Fu Fung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 98-102). / Abstract also in Chinese. / Abstract --- p.iv / Acknowledgements --- p.vi / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Medical Visualization System --- p.4 / Chapter 1.1.1 --- Data Acquisition --- p.4 / Chapter 1.1.2 --- Computer-aided Medical Visualization --- p.5 / Chapter 1.1.3 --- Existing Systems --- p.6 / Chapter 1.2 --- Research Goal --- p.8 / Chapter 1.2.1 --- System Architecture --- p.9 / Chapter 1.3 --- Organization of this Thesis --- p.10 / Chapter 2 --- Volume Visualization --- p.11 / Chapter 2.1 --- Sampling Grid and Volume Representation --- p.11 / Chapter 2.2 --- Priori Work in Volume Rendering --- p.13 / Chapter 2.2.1 --- Surface VS Direct --- p.14 / Chapter 2.2.2 --- Image-order VS Object-order --- p.18 / Chapter 2.2.3 --- Orthogonal VS Perspective --- p.22 / Chapter 2.2.4 --- Hardware Acceleration VS Software Acceleration --- p.23 / Chapter 2.3 --- Chapter Summary --- p.29 / Chapter 3 --- IsoRegion Leaping Technique for Perspective Volume Rendering --- p.30 / Chapter 3.1 --- Compositing Projection in Direct Volume Rendering --- p.31 / Chapter 3.2 --- IsoRegion Leaping Acceleration --- p.34 / Chapter 3.2.1 --- IsoRegion Definition --- p.35 / Chapter 3.2.2 --- IsoRegion Construction --- p.37 / Chapter 3.2.3 --- IsoRegion Step Table --- p.38 / Chapter 3.2.4 --- Ray Traversal Scheme --- p.41 / Chapter 3.3 --- Experiment Result --- p.43 / Chapter 3.4 --- Improvement --- p.47 / Chapter 3.5 --- Chapter Summary --- p.48 / Chapter 4 --- Parallel Volume Rendering by Distributed Processing --- p.50 / Chapter 4.1 --- Multi-platform Loosely-coupled Parallel Environment Shell --- p.51 / Chapter 4.2 --- Distributed Rendering Pipeline (DRP) --- p.55 / Chapter 4.2.1 --- Network Architecture of a Loosely-Coupled System --- p.55 / Chapter 4.2.2 --- Data and Task Partitioning --- p.58 / Chapter 4.2.3 --- Communication Pattern and Analysis --- p.59 / Chapter 4.3 --- Load Balancing --- p.69 / Chapter 4.4 --- Heterogeneous Rendering --- p.72 / Chapter 4.5 --- Chapter Summary --- p.73 / Chapter 5 --- User Interface --- p.74 / Chapter 5.1 --- System Design --- p.75 / Chapter 5.2 --- 3D Pen Input Device --- p.76 / Chapter 5.3 --- Visualization Environment Integration --- p.77 / Chapter 5.4 --- User Interaction: Interactive Navigation --- p.78 / Chapter 5.4.1 --- Camera Model --- p.79 / Chapter 5.4.2 --- Zooming --- p.81 / Chapter 5.4.3 --- Image View --- p.82 / Chapter 5.4.4 --- User Control --- p.83 / Chapter 5.5 --- Chapter Summary --- p.87 / Chapter 6 --- Conclusion --- p.88 / Chapter 6.1 --- Final Summary --- p.88 / Chapter 6.2 --- Deficiency and Improvement --- p.89 / Chapter 6.3 --- Future Research Aspect --- p.91 / Appendix --- p.93 / Chapter A --- Common Error in Pre-multiplying Color and Opacity --- p.94 / Chapter B --- Binary Factorization of the Sample Composition Equation --- p.96
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Morphogénèse épithélio-mésenchymateuse au cours du développement pulmonaire précoce. / Epithelio-mesenchymal morphogenesis during early pulmonary development.

Blanc, Pierre 29 October 2012 (has links)
[Copie de la conclusion de la thèse, en l'absence de résumé disponible] La morphogénèse bronchique est-elle l’œuvre de programmes et sous-programmes ou bien est-elle un phénomène partiellement auto-organisé à la faveur d’une régulation moléculaire parcimonieuse ? L’étude tridimensionnelle in-vivo que nous avons menée au stade pseudo-glandulaire précoce révèle que la structure de l’arbre est moins stéréotypée que ce qui est classiquement décrit et qu’elle ne peut être interprétée indépendamment de la croissance du mésenchyme et des tissus environnants. Ensemble, les variations observées dans le temps, l’espace ou la morphologie des branchements rendent peu probable l’existence d’un programme qui prédéfinirait où, quand, comment chaque branchement doit s’effectuer. Sans compter la complexité d’un tel programme, la manière dont il pourrait être écrit en langage moléculaire demeure obscure. En contexte sauvage, les variations – y compris celles qui ont été considérées comme d’authentiques erreurs – n’entravent jamais le processus de branchement. Celui-ci continue à se dérouler de telle sorte que l’espace est rempli sans conflits ni lacunes. Cela suggère fortement que les tubes épithéliaux sont capables de s’adapter en temps réel à la configuration des bourgeons et du mésenchyme environnant. Intuitivement, il est sans doute beaucoup plus simple de coordonner la croissance épithélio-mésenchymateuse et d’autoriser les bourgeons à remplir l’espace en s’auto-évitant que d’écrire un programme contenant le plan complet de l’organe.Nous montrons qu’un mécanisme simple fondé sur la diffusion d’un facteur de croissance clef (FGF10) permet d’organiser une croissance branchée. La dynamique laplacienne qui se met en place dans une géométrie mouvante provoque spontanément l’apparition de doigts dont l’extrémité se déstabilise de manière itérative pour produire une arborescence. Chaque branche de l’arbre remplit au fur et à mesure l’espace qui se développe dans le mésenchyme en s’auto-évitant. Les deux articles présentés introduisent donc une rupture conceptuelle en proposant que le plan de l’arbre bronchique ne soit pas « préprogrammé ». La morphogénèse de l’arbre bronchique est vraisemblablement régulée en temps réel par instruction réciproque de l’épithélium et du mésenchyme, au moyen d’un nombre réduit de boucle de régulation. / [This abstract is the conclusion of the dissertation] Is bronchial morphogenesis the result of programs and sub-programs or is it a partially self-organized phenomenon thanks to parsimonious molecular regulation? The three-dimensional in vivo study that we conducted at the early pseudo-glandular stage reveals that the structure of the tree is less stereotyped than is conventionally described and that it can not be interpreted independently of the growth of mesenchyme and surrounding tissues. Together, the variations observed in the time, the space or the morphology of the connections make it unlikely the existence of a program that predefines where, when, how each connection must be made. Not to mention the complexity of such a program, the way it could be written in molecular language remains unclear.In the wild context, variations - including those that have been considered genuine mistakes - never hinder the connection process. It continues to unfold so that the space is filled without conflicts or gaps. This strongly suggests that the epithelial tubes are able to adapt in real time to the configuration of buds and surrounding mesenchyme. Intuitively, it is probably much simpler to coordinate the epithelio-mesenchymal growth and to allow the buds to fill the space by self-avoidance than to write a program containing the complete organ plan.We show that a simple mechanism based on the diffusion of a key growth factor (FGF10) allows to organize a trendy growth. The Laplacian dynamics that is set up in a moving geometry spontaneously causes the appearance of fingers whose end is destabilized iteratively to produce a tree. Each branch of the tree gradually fills the space that develops in the mesenchyme by self-avoiding.The two articles presented thus introduce a conceptual break by proposing that the plane of the bronchial tree is not "preprogrammed". Morphogenesis of the bronchial tree is likely to be regulated in real time by reciprocal instruction of the epithelium and mesenchyme, by means of a reduced number of regulation loop.
29

The effects of lung inflation on pulmonary and bronchial circulations in dogs

龍建音, Lung, Kin-yum, Mary Agnes. January 1979 (has links)
published_or_final_version / Physiology / Doctoral / Doctor of Philosophy
30

Expression and function of chemokine receptors on airway smooth muscle cells

Joubert, Philippe. January 2007 (has links)
Asthma is a respiratory disease that affects 2.5-3 million Canadians. This condition is characterized by a Th2-driven immune response that implicates the infiltration of eosinophils and remodelling of the airways. In the last decade, airway smooth muscle cells (ASMC) have became the subject of intense research in the field of inflammatory lung diseases including asthma. It is known that ASMC respond to a wide variety of inflammatory mediators such as cytokines and chemokines. Function of ASMC in the context of asthma has extended beyond its traditional role of a structural cell. Indeed, it is believed that they can participate in the initiation and the perpetuation of the inflammatory response that takes place in the airway of asthmatic subjects. The general aim of this work was to investigate the role of ASMC in the pathogenesis of asthma. More specifically, we studied the expression of two C-C chemokine receptors, CCR3 and CCR1 in the context of asthma. / For the first time, this work describes the expression of chemokine receptors by ASMC. We have shown that eotaxin, an important chemokine in asthma, induces migration of ASMC through the activation of CCR3. Although CCR3 expression is not regulated by Th2 cytokines in vitro, ASMC isolated from asthmatic patients expressed intrinsically higher levels of the surface receptor when compared to controls. We also describe the expression of CCR1 by ASMC, a receptor involved in airway remodelling in an animal model of asthma. We reported the expression of CCR1 mRNA in biopsies obtained from mild, moderate and severe asthmatics and showed that mild group express the highest level of CCR1. We also confirmed that ASMC express the receptor in vivo and showed that stimulation of this receptor with its ligands induces intra-cellular calcium mobilization, which confirms its functionality. Regulation of CCR1 on ASMC was also assessed using proinflammatory, Th1 and Th2 cytokines. We found that TNF-alpha and to a lesser extent, IFN-gamma, upregulated CCR1 mRNA and protein expression, while Th2 cytokines had no effect. The effect of these two cytokines was totally suppressed by either dexamethasone or mithramycin. / Collectively, our results demonstrate the expression of functional C-C chemokine receptors by ASMC. Interestingly, we have shown that CCR3 activation mediates ASMC migration and provides a new possible mechanism for the increased smooth muscle mass observed in asthmatic patients. Although the exact function of the CCR1 expressed by ASMC is unknown, our results suggest an involvement in asthma pathogenesis, possibly through airway remodelling.

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