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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.
171

Identification of molecular targets regulating fatty acid synthesis in bovine mammary epithelial cells

McFadden, Joseph William 05 May 2009 (has links)
Consumer demand for milk fat has declined due to the increased risk of cardiovascular disease associated with consuming a high saturated fat diet. Milk fat synthesis is energetically expensive for the dairy cow, especially during early lactation or periods of poor nutrition. Thus, manipulating milk fat production and composition may promote the synthesis of more market-valuable milk components and improve energy utilization in dairy cows during periods of increased energy demand. Therefore, the objective of the present studies was to identify molecular proteins that regulate fatty acid synthesis in bovine mammary epithelial cells. The regulation of lipogenic genes including acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) is controlled by transcription factors including sterol regulatory element binding protein-1 (SREBP1) and liver X receptor (LXR). In vivo, diet-induced milk fat depression or supplementing diets with polyunsaturated fatty acids inhibits milk fat synthesis by regulating SREBP1 expression. Results confirm that polyunsaturated fatty acids inhibit fatty acid synthesis in bovine mammary epithelial cells by regulating the expression of SREBP1. In hepatocytes, LXR can regulate the transcription of SREBP1 in addition to ACC and FAS. Results confirm that LXR activation enhanced synthesis of fatty acids in bovine mammary epithelial cells by promoting the transcription of FAS and SREBP1. Activation of LXR was unable to prevent the inhibitory effect of polyunsaturated fatty acids on fatty acid synthesis. In the lactating mammary gland, LXR may contribute to the synthesis of fatty acids by regulating the expression of SREBP1. In addition to modifying the expression of lipogenic genes, some enzymes can be phosphorylated by AMP-activated protein kinase (AMPK), an energy-sensing protein, inhibiting their activity. Presence of AMPK mRNA was identified in bovine mammary epithelial cells and activation of AMPK dramatically decreased fatty acid synthesis in bovine mammary epithelial cells. In the lactating mammary gland, AMPK may sense energy availability and regulate milk fat synthesis to control energy utilization. Identification of SREBP1, LXR, and AMPK as regulators of fatty acid synthesis in bovine mammary epithelial cells may lead to the development of technologies allowing dairy producers to modify milk fat production and composition to meet consumer demand and maximize profitability. / Ph. D.
172

Extracellular Proteoglycan Decorin in Bovine Mammary Physiology

Tucker, Hannah L. 27 September 2017 (has links)
The majority of bovine mammary gland research focuses on the main cell types - mammary epithelial cells and fibroblasts. However, the extracellular matrix (ECM) within the mammary gland is also of importance for its ability to regulate cell shape, proliferation, polarity, differentiation, gene transcription, protein synthesis, and secretion. Decorin is an ECM proteoglycan known to impact mammary cell proliferation in humans and rodents. Prior to this work, very little was known about decorin in bovine mammary biology. A series of bovine mammary cell culture experiments was conducted. The first experiment demonstrated existence of decorin pathway molecules in immortalized bovine mammary cells, but stopped short of demonstrating mature decorin proteoglycan deposition into the extracellular space. During the investigation it was noted that when cultured under basal conditions, intracellular decorin core protein (DCP) localization patterns appeared to be coordinated with specific phases of the cell cycle. Therefore, the objective of the second set of experiments was to characterize DCP localization patterns in bovine mammary epithelial cells (BME) at known phases of the cell cycle. The work was carried out in two sequential experiments. The hypothesis of the first experiment was that DCP accumulates in BME during S-phase of the cell cycle; the research rejected this hypothesis. The hypothesis of the second experiment, formulated after completion of the first experiment for this objective, was that DCP accumulates in BME during metaphase of the cell cycle. However, the experiment was unable to confirm of reject this hypothesis. Major findings were that both BME and mammary fibroblasts produce DCP and known decorin pathway molecules. BME produce intracellular DCP, but it is not accumulated during the S-phase of the cell cycle. However, it is still unknown if DCP is accumulated in BME during metaphase. Future research should focus on further characterization of decorin and its associated pathway molecules to learn if decorin induces proliferation or apoptosis of bovine mammary epithelial cells. This is important because number and activity of mammary epithelial cells ultimately determine milk yield in dairy cows. Fundamental knowledge gained in this research area may one day be applied at the animal-level and lead to gains in milk production efficiency by altering the cellular composition of mammary glands. / Ph. D.
173

Poly(n-butyl Methacrylate) with Primary Amine End Groups for Supporting Cell Adhesion and Proliferation of Renal Epithelial Cells

Cox-Nowak, K., Al-Yamani, Ohood, Grant, Colin A., Green, N.H., Rimmer, Stephen 08 February 2017 (has links)
Yes / Polymer coatings that support epithelial cell culture have been developed. Ozonolysis and subsequent work up of poly(butyl methacrylate-co-butadiene) copolymers is used to form oligomers with carboxylic acid end groups, which are then further reacted with diamines to provide poly(butyl methacrylate)s with primary amine end groups. The polymers are cast as films and used as cell culture substrates for human dermal fibroblasts and human renal epithelial cells. Fibroblast and epithelial cells adhere and proliferate on acid functional materials but on amine functional films epithelial cells show greater viability than fibroblasts.
174

Characterization of aberrantly expressed microRNAs in Epstein-Barr virus-associated nasopharyngeal carcinoma. / CUHK electronic theses & dissertations collection

January 2013 (has links)
鼻咽癌(nasopharyngeal carcinoma, NPC)與艾巴氏病毒(Epstein-Barr virus, EBV)和遺傳及表現遺傳變異有連串關係。儘管鼻咽癌腫瘤的發生機制仍然未知,最近研究顯示微核糖核酸(microRNA, miRNA)通過調節細胞增殖凋亡遷移和侵襲等方式對鼻咽癌的生成起著至關重要的作用。為了確定微核糖核酸與鼻咽癌發生的相關機制及其扮演的角色,我們集中研究微核糖核酸在鼻咽癌腫瘤中所發生的變異,探討這些異常表達的微核糖核酸的功能,並揭開與幹細胞相關的微核糖核酸在鼻咽癌幹細胞樣細胞(cancer stem-like cell, CSC)裏所扮演的角色。 / 通過使用微陣列技術(Agilent Microarray), 我們運用了 866個人類與 89個病毒微核糖核酸探針,以識別出多個帶有艾巴氏病毒的鼻咽癌腫瘤細胞系裏的微核糖核酸表達圖譜。相比正常的鼻咽上皮細胞系NP69,113個微核糖核酸在鼻咽癌中的差異表達已被鑒定出來。其中58個在鼻咽癌裏下調的微核糖核酸表達,miR-31的轉錄下調現象在鼻咽癌腫瘤細胞系和原發腫瘤中被不斷地發現。在7個帶有艾巴氏病毒的腫瘤細胞系樣本裏, 其中6個(86%)樣本呈miR-31下調跡象。與此同時,以顯微切割技術所得的38個原發腫瘤樣本中全部(100%)都顯示有miR-31下調的跡象。相比之下,所有正常的鼻咽上皮細胞都顯出高表達的miR-31。 / miR-31位於染色體9p21.3上,距離CDKN2A (p16) 0.5Mb處。這是在鼻咽癌細胞裏通常缺失的位置。在X1915和X99186腫瘤細胞系中,已證實在miR-31和CDKN2A位點上都出現了純合性缺失。在四株不具備miR-31缺失的腫瘤細胞系裏,甲基化特異性聚合酶連鎖反應 (methylation-specific PCR, MSP) 和亞硫酸氫鈉測序法(bisulfite sequencing)發現了高甲基化的CpG島。使用5-aza-2’-deoxycytidine (5-Aza-dC) 治療後,鼻咽癌細胞株C666-1被證實恢復了miR-31轉錄。這些結果表明,純合性缺失和啟動子高甲基化是造成miR-31在鼻咽癌裏轉錄失效的主要發生機制。 / 微陣列技術和生物信息學分析找出了一些可能受miR-31影響的基因。其中FIH1和MCM2被確定為在鼻咽癌細胞裏受miR-31影響的基因。我們證實miR-31與FIH1和MCM2 信使核糖核酸的3’UTR處結合會抑制螢光素酶的活性。在鼻咽癌細胞裏miR-31的異位表達也會壓抑FIH1和MCM2蛋白的表達。更重要的是,恢復正常的miR-31表達或敲除FIH1表達能顯著地抑制C666-1細胞的增殖和移動能力。C666-1細胞的克隆形成能力和錨定依賴性生長都顯著地被miR-31的表達所抑制。穩定的miR-31表達亦能抑制鼻咽癌腫瘤在裸鼠體內的生長。此外,FIH1的敲除加強了p21和磷酸化p53 (Ser15) 的表達。這些結果暗示了miR-31是一個與鼻咽癌至關重要的微核糖核酸。 它通過了對FIH1的壓制,負面地調節細胞的增殖和移動。 / 使用微核糖核酸微陣列分析後,我們在鼻咽癌細胞中培養的懸浮細胞球裏篩選出差異表達的微核糖核酸。同樣地,實時螢光定量逆轉錄聚合酶鏈反應(qRT-PCR) 亦證實了miR-96和miR-183在C666-1懸浮細胞球裏是被抑制的。此外,miR-96和miR-183的異位表達顯著地降低了C666-1懸浮細胞球形成和克隆形成的能力。這項研究結果暗示, miR-96和miR-183的抑制對鼻咽癌幹細胞樣細胞的形成非常重要。 / 總的來說,某些微核糖核酸已被確定為潛在的鼻咽癌腫瘤抑制基因。 在帶艾巴氏病毒的鼻咽癌裏,miR-31的表達被證實是因純合性缺失和啟動子高甲基化而被下調的。miR-31抑制鼻咽癌細胞的增殖錨定依賴性生長細胞遷移和體內腫瘤的生長。同時,miR-96和miR-183也被發現對維持鼻咽癌的幹細胞樣特性起著一定作用。這些結果表明微核糖核酸對鼻咽癌腫瘤的生成扮演著抑制的角色。對微核糖核酸的機制作進一步全面了解將改進鼻咽癌的治療策略。 / Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC) has been reported to be related to a number of genetic and epigenetic changes, however, the molecular mechanism leading to NPC tumorigenesis still remains unclear. Recently, microRNAs (miRNAs) have been demonstrated to play vital roles in NPC development via regulating cell proliferation, apoptosis, and cell migration and invasion. In this study, we aim to elucidate the role of miRNAs in NPC tumorigenesis in this study by identifying the miRNA aberration, investigating the possible functions of these aberrantly expressed miRNAs, and unraveling the role of stemness-related miRNAs in NPC cancer stem-like cells (CSCs). / By using Agilent Microarray with 866 human and 89 viral miRNA probes, miRNA expression profiles of multiple EBV-associated NPC tumor lines were generated. Compared to NP69, a nonmalignant nasopharyngeal epithelial cell line, 113 differentially expressed miRNAs were identified. Among the 58 down-regulated miRNAs in NPC, transcriptional silencing of miR-31 was consistently found in both NPC tumor lines and primary tumors. Down-regulation of miR-31 was detected in 6 of 7 (86%) EBV-positive tumor lines and 38 of 38 (100%) microdissected primary tumors, while all normal nasopharyngeal epithelia showed high expression of miR-31. / miR-31 is located at 0.5 Mb telomeric to CDKN2A (p16) on chromosome 9p21.3, which is commonly deleted in NPC. Homozygous deletion of both miR-31 and CDKN2A loci was confirmed in tumor lines X1915 and X99186. In the four tumor lines with intact miR-31, hypermethylation of 5’ CpG islands was detected by methylation-specific PCR (MSP) and bisulfite sequencing analysis. Restoration of miR-31 transcription was demonstrated in the EBV-positive NPC cell line C666-1 treated with 5-aza-2’-deoxycytidine. These findings suggested that homozygous deletion and promoter hypermethylation are the major mechanisms for transcriptional silencing of miR-31 in NPC. / By microarray and bioinformatic analysis, a number of putative targets of miR-31 were identified. Among these candidates, FIH1 and MCM2 were found to be the targets of miR-31 in NPC. We have shown that binding of miR-31 on FIH1 and MCM2 mRNA 3’UTR suppressed their luciferase activity. Ectopic expression of miR-31 in NPC cells resulted in repression of FIH1 and MCM2 protein expression. Importantly, the restoration of miR-31 or knockdown of FIH1 expression significantly suppressed proliferation as well as migration of C666-1 cells. Clone-forming ability and anchorage-independent growth of C666-1 were significantly inhibited by miR-31 expression. Stably expressed miR-31 was also demonstrated to inhibit NPC tumor growth in nude mice. Furthermore, expression of p21 and phospho-p53 (Ser15) was found to be increased by FIH1 knockdown. These results implied that miR-31 is a critical NPC-associated miRNA which negatively regulates cell proliferation and migration via FIH1 repression. / By miRNA microarray analysis, we have screened for differentially expressed miRNAs in sphere-forming cells of EBV-associated NPC. In concordance with microarray findings, suppression of miR-96 and miR-183 in C666-1 spheroids was confirmed by qRT-PCR. Ectopic expression of miR-96 and miR-183 significantly reduced the sphere-forming and clone-forming ability of C666-1 cells. The findings implied that miR-96 and miR-183 repression is important in the formation of NPC CSCs. / In summary, several miRNAs were identified as potential tumor suppressor genes in NPC. miR-31 was found down-regulated by homozygous deletion or promoter hypermethylation in EBV-associated NPC. It plays roles in NPC pathogenesis by suppressing NPC cell proliferation, clone-forming ability, cell anchorage-independent growth, migration and in vivo tumor growth. Moreover, miR-96 and miR-183 were found to have a role in the maintenance of NPC stem-like properties. These findings suggested important tumor suppressive roles of miRNAs in regulating NPC tumorigenesis, and a better understanding on the miRNA mechanisms may potentiate better therapeutic strategies for NPC. / 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. / Cheung, Ching Mei. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 177-209). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese. / Abstract --- p.i / 摘要 --- p.iv / Thesis / Assessment Committee --- p.vii / Acknowledgements --- p.viii / Table of contents --- p.ix / List of figures --- p.xv / List of tables --- p.xviii / List of publications --- p.xix / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Nasopharyngeal carcinoma (NPC) --- p.1 / Chapter 1.1.1 --- Histopathology and epidemiology --- p.1 / Chapter 1.1.2 --- Etiology --- p.2 / Chapter 1.1.2.1 --- Environmental factors --- p.2 / Chapter 1.1.2.2 --- Genetic factors --- p.3 / Chapter 1.1.2.3 --- Epstein-Barr virus (EBV) infection --- p.3 / Chapter 1.2 --- Molecular pathogenesis of NPC --- p.5 / Chapter 1.2.1 --- Cytogenetic changes --- p.5 / Chapter 1.2.2 --- NPC-associated tumor suppressor genes (TSGs) --- p.6 / Chapter 1.2.3 --- NPC-associated oncogenes --- p.8 / Chapter 1.3 --- MicroRNAs --- p.10 / Chapter 1.3.1 --- Biogenesis of microRNAs --- p.10 / Chapter 1.3.2 --- MicroRNAs and cancers --- p.15 / Chapter 1.3.2.1 --- MicroRNAs - tumor suppressors --- p.15 / Chapter 1.3.2.2 --- MicroRNAs - oncogenes --- p.16 / Chapter 1.4 --- MicroRNAs in nasopharyngeal carcinoma --- p.18 / Chapter 1.4.1 --- MicroRNA profiling in NPC --- p.18 / Chapter 1.4.2 --- OncomiRs in NPC --- p.20 / Chapter 1.4.3 --- Tumor suppressor miRNAs in NPC --- p.22 / Chapter 1.4.4 --- miRNAs and cancer stem-like cells (CSCs) --- p.27 / Chapter 1.4.5 --- Clinical implication of miRNAs in NPC --- p.29 / Chapter 1.5 --- Aims of study --- p.32 / Chapter Chapter 2 --- Materials and methods --- p.34 / Chapter 2.1 --- Patient biopsies --- p.34 / Chapter 2.2 --- NPC cell lines and xenografts --- p.34 / Chapter 2.2.1 --- Cell lines --- p.34 / Chapter 2.2.2 --- Xenografts --- p.36 / Chapter 2.3 --- Total RNA Isolation --- p.39 / Chapter 2.4 --- DNA extraction --- p.39 / Chapter 2.5 --- Protein Extraction --- p.40 / Chapter 2.6 --- Western Blotting --- p.40 / Chapter 2.7 --- Microarray analysis --- p.43 / Chapter 2.7.1 --- MicroRNA microarray --- p.43 / Chapter 2.7.2 --- Gene expression microarray --- p.44 / Chapter 2.8 --- Quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR) --- p.45 / Chapter 2.8.1 --- Conventional qRT-PCR --- p.45 / Chapter 2.8.2 --- Stem-looped qRT-PCR --- p.46 / Chapter 2.9 --- Preparation of stable clone of miR-31 --- p.51 / Chapter 2.9.1 --- Cloning and plasmid DNA preparation --- p.51 / Chapter 2.9.1.1 --- Bacterial Transformation --- p.51 / Chapter 2.9.1.2 --- Plasmid DNA Extraction --- p.51 / Chapter 2.9.2 --- DNA Sequencing --- p.52 / Chapter 2.9.3 --- Stable transfection --- p.52 / Chapter 2.9.4 --- Clone selection --- p.53 / Chapter 2.10 --- Transient transfection --- p.55 / Chapter 2.11 --- Flow cytometry --- p.55 / Chapter 2.11.1 --- Apoptosis analysis by Annexin V --- p.55 / Chapter 2.11.2 --- Cell cycle analysis by propidium iodide (PI) --- p.56 / Chapter 2.11.3 --- Detection of stem-like cell markers --- p.56 / Chapter 2.12 --- Cell proliferation analysis --- p.56 / Chapter 2.12.1 --- WST-1 assay --- p.56 / Chapter 2.12.2 --- BrdU assay --- p.57 / Chapter 2.13 --- Anchorage-independent growth assay --- p.58 / Chapter 2.14 --- Clone formation assay --- p.58 / Chapter 2.15 --- Cell migration assay --- p.54 / Chapter 2.16 --- In vivo tumorigenicity --- p.59 / Chapter 2.17 --- Dual luciferase reporter assay --- p.60 / Chapter 2.17.1 --- Luciferase reporter vectors --- p.60 / Chapter 2.17.2 --- Luciferase reporter assay --- p.60 / Chapter 2.18 --- Mapping homozygous deletion and genes in chromosome 9p21.3 --- p.64 / Chapter 2.19 --- 5-aza-2’-deoxycytidine (5-Aza-dC) and Trichostatin A (TSA) treatments --- p.64 / Chapter 2.20 --- Methylation specific-PCR (MSP) and bisulfite sequencing analysis --- p.68 / Chapter 2.20.1 --- Bisulfite modification --- p.68 / Chapter 2.20.2 --- Methylation specific-PCR (MSP) --- p.69 / Chapter 2.20.3 --- Bisulfite sequencing analysis --- p.69 / Chapter 2.21 --- Statistical analysis --- p.70 / Chapter 2.22 --- In situ hybridization (ISH) analysis --- p.73 / Chapter Chapter 3 --- Identification of novel deregulated microRNAs in nasopharyngeal carcinoma --- p.74 / Chapter 3.1 --- Introduction --- p.74 / Chapter 3.2 --- Results --- p.80 / Chapter 3.2.1 --- Aberrant expression of microRNAs in NPC --- p.80 / Chapter 3.2.2 --- Homozygous deletion of miR-31 in NPC --- p.90 / Chapter 3.2.3 --- Hypermethylation of 5’ CpG islands of miR-31 in NPC --- p.92 / Chapter 3.2.4 --- Detection of miR-31 expression in normal epithelia and NPC by in situ hybridization --- p.99 / Chapter 3.3 --- Discussion --- p.101 / Chapter Chapter 4 --- Characteristics of miR-31 and its targets in NPC --- p.105 / Chapter 4.1 --- Introduction --- p.105 / Chapter 4.2 --- Results --- p.107 / Chapter 4.2.1 --- Effects of exogenous miR-31 on NPC cells --- p.107 / Chapter 4.2.1.1 --- miR-31 effect on C666-1 cell proliferation and cell cycle progression --- p.107 / Chapter 4.2.1.2 --- Clone-forming ability and anchorage-independent growth of C666-1 --- p.113 / Chapter 4.2.1.3 --- Migration ability of C666-1 --- p.113 / Chapter 4.2.2 --- Effects of stably expressed miR-31 on NPC cells --- p.117 / Chapter 4.2.2.1 --- Stable clones selection by restoring precursor of miR-31 into C666-1 --- p.117 / Chapter 4.2.2.2 --- Cell proliferation and cell cycle progression in stable clones of miR-31 --- p.117 / Chapter 4.2.2.3 --- Anchorage-independent growth of C666-1 stable clones --- p.117 / Chapter 4.2.2.4 --- Tumorigenicity of C666-1 stable clones expressing miR-31 in vivo --- p.118 / Chapter 4.2.3 --- Identification of miR-31 targets in NPC cells --- p.125 / Chapter 4.2.3.1 --- miR-31 targets FIH1 and MCM2 --- p.125 / Chapter 4.2.3.2 --- Other reported targets of miR-31 in NPC --- p.131 / Chapter 4.2.4 --- Functional analysis of FIH1 in NPC cells --- p.133 / Chapter 4.2.4.1 --- Repression of FIH1 by siRNAs --- p.133 / Chapter 4.2.4.2 --- Proliferation of C666-1 with FIH1 knockdown --- p.133 / Chapter 4.2.4.3 --- Clone-forming and migration ability of C666-1 transfected with siFIH1 --- p.133 / Chapter 4.2.4.4 --- Putative downstream targets of FIH1 --- p.139 / Chapter 4.2.5 --- Identification of novel miR-31 targets by gene expression microarray --- p.139 / Chapter 4.3 --- Discussion --- p.145 / Chapter Chapter 5 --- MicroRNAs regulation on NPC stem-like properties --- p.154 / Chapter 5.1 --- Introduction --- p.154 / Chapter 5.2 --- Results --- p.156 / Chapter 5.2.1 --- MicroRNA expression profiles in NPC sphere-forming cells --- p.155 / Chapter 5.2.2 --- Ectopic expression of miR-183 family and miR-203 in NPC --- p.161 / Chapter 5.2.2.1 --- Sphere-forming ability of NPC cells --- p.161 / Chapter 5.2.2.2 --- Clone-forming ability of C666-1 --- p.161 / Chapter 5.2.3 --- Sphere-forming ability of NPC cells transfected with anti-miR-96 and anti-miR-183 --- p.164 / Chapter 5.2.4 --- Expression of cacner stem cell markers in NPC cells transfected with miR-96 and miR-183 --- p.164 / Chapter 5.3 --- Discussion --- p.167 / Chapter Chapter 6 --- General discussion --- p.170 / Reference --- p.177
175

Signaling pathways involved in the poly-L-arginine - induced IL-6 and IL-8 release in cultured human bronchial epithelial cells, 16HBE14o-.

January 2010 (has links)
Liang, Fengting. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 87-101). / Abstracts in English and Chinese. / DECLARATION --- p.I / ACKNOWLEDGEMENT --- p.II / ABBREVIATIONS --- p.III / ABSTRACT IN ENGLISH --- p.IV / ABSTRACT IN CHINESE --- p.VI / TABLE OF CONTENTS --- p.VIII / LIST OF FIGURES --- p.XI / LIST OF TABLES --- p.XIII / Chapter CHAPTER I- --- INTRODUCTION / Chapter 1.1 --- Roles of human bronchial epithelial cells --- p.1 / Chapter 1.2 --- Role of epithelium in airway inflammation --- p.3 / Chapter 1.3 --- Pathology of asthma --- p.5 / Chapter 1.4 --- The role of eosinophils in asthma --- p.7 / Chapter 1.5 --- "Effects of poly-L-arginine, a MBP analogue, on airway epithelium" --- p.10 / Chapter 1.6 --- Inflammatory pathways involved in epithelial cytokine production --- p.12 / Chapter 1.7 --- Roles and function of IL-6 and IL-8 in epithelial cells --- p.16 / Chapter 1.8 --- P2 receptors and inflammation --- p.18 / Chapter 1.9 --- Objectives --- p.20 / Chapter CHAPTER II- --- MATERIALS AND METHODS / Chapter 2.1 --- Materials and regents --- p.21 / Chapter 2.2 --- Cell culture --- p.22 / Chapter 2.3 --- RNA extraction and Real-time PCR --- p.23 / Chapter 2.4 --- Measurement of cytokine secretion by antibody array --- p.24 / Chapter 2.5 --- Quantification of IL-6 and IL-8 secretion --- p.27 / Chapter 2.6 --- Western Blotting --- p.28 / Chapter 2.7 --- NF-kB translocation assay --- p.29 / Chapter 2.8 --- Data analysis --- p.30 / Chapter CHAPTER III- --- RESULTS / Chapter 3.1 --- Poly-L-arginine-induced IL-6 and IL-8 release from 16HBE 14o- --- p.31 / Chapter 3.2 --- Signaling pathways involved in poly-L-arginine-induced IL-6 and IL-8 release --- p.34 / Chapter 3.2.1 --- "Effects of p38 MAPK, ERK1/2 and NF-kB inhibitors on poly-L-arginine-induced IL-6 and IL-8 release" --- p.35 / Chapter 3.2.2 --- Poly-L-arginine induces p38 MAPK and ERK1/2 phosphorylation --- p.43 / Chapter 3.2.3 --- Poly-L-arginine activates NF-kB translocation from cytoplasm to nucleus --- p.49 / Chapter 3.3 --- Effects of MAPK and NF-kB inhibitors on IL-6 and IL-8 mRNA expression on poly-L-arginine-challenged 16HBE14o- cells --- p.52 / Chapter 3.4 --- P2 receptors modulate poly-L-arginine-induced IL-6 and IL-8 ^ production --- p.55 / Chapter 3.4.1 --- Extracellular nucleotides modulate IL-6 and IL-8 production --- p.56 / Chapter 3.4.2 --- Effects of P2Y6 antagonist on poly-L-arginine-induced IL-6 and IL-8 production --- p.61 / Chapter 3.4.3 --- Effects of MAPKs inhibitors on UDP-induced IL-6 and IL-8 secretion --- p.64 / Chapter 3.4.4 --- UDP induces NF-kB translocation in 16HBE14o- cells --- p.67 / Chapter CHAPTER IV- --- DISCUSSION / Chapter 4.1 --- Involvement of p3 8 MAPK and NF-kB in poly-L-arginine-induced IL-6 and IL-8 secretion --- p.70 / Chapter 4.2 --- Involvement of p38 MAPK and NF-kB in poly-L-arginine-induced IL-6 and IL-8 mRNA elevation --- p.72 / Chapter 4.2.1 --- Regulation of NF-kB on IL-6 and IL-8 mRNA --- p.73 / Chapter 4.2.2 --- Regulation of p38 MAPK on IL-6 and IL-8 mRNA --- p.75 / Chapter 4.2.3 --- Crosstalk between NF-kB and p38 MAPK --- p.77 / Chapter 4.3 --- Extracellular nucleotides mediate IL-6 and IL-8 production in 16HBE14o- --- p.79 / Chapter 4.3.1 --- P2Y6 receptor is linked to poly-L-arginine-induced IL-6 and IL-8 release --- p.80 / Chapter 4.3.2 --- P2Y6 receptor regulates IL-6 and IL-8 secretion via p38 MAPK and NF-kB --- p.83 / Chapter 4.4 --- Summary --- p.86 / Chapter CHAPTER V- --- References --- p.87 / Publications --- p.102
176

Role of Epithelium-specific ETS Transcription Factor-1 in Airway Epithelial Regeneration

Oliver, Jordan 26 March 2012 (has links)
Human epithelium-specific ETS transcription factor-1 (ESE-1), which is also known as E74-like factor-3 (Elf3) in mice, is strongly expressed in lung during fetal development and in certain lung cancers. The primary goal of the work presented in this thesis was to investigate whether ESE-1 is involved in regeneration of the injured lung epithelium by administering naphthalene to both wild-type (Elf3 +/+) and Elf3-deficient (Elf3 -/-) mice. However, optimal conditions for proper utilization of the naphthalene-induced lung injury model must first be established. Therefore, dose-response studies were initially conducted by administering three different doses of naphthalene to both male and female mice, as described in chapter 2. Although it is shown that the extent of naphthalene-induced Clara cell injury is dose-dependent in both male and female mice, female mice are more sensitive to naphthalene-induced injury than male mice independent of the dose. Furthermore, it is also demonstrated that these gender-dependent differences in naphthalene injury can subsequently influence downstream lung repair kinetics. In light of these findings, lung regeneration was examined in both sexes of both Elf3 +/+ and Elf3 -/- mice. As reported in chapter 3, the kinetics of bronchiolar epithelial cell proliferation and differentiation is delayed considerably in Elf3 -/- mice following naphthalene injury. Moreover, expression of transforming growth factor-beta type II receptor, which is a well-known transcriptional target gene of ESE-1 and is involved in the induction of epithelial cell differentiation, is significantly lower in the bronchiolar airway epithelium of Elf3 -/- mice as compared to Elf3 +/+ mice under steady-state conditions and during repair of naphthalene-induced damage. Collectively, these findings occur to a similar extent in both sexes of both Elf3 +/+ and Elf3 -/- mice, and suggest that ESE-1 plays an important role in regulating the kinetics of airway epithelial regeneration after acute lung injury.
177

Role of Epithelium-specific ETS Transcription Factor-1 in Airway Epithelial Regeneration

Oliver, Jordan 26 March 2012 (has links)
Human epithelium-specific ETS transcription factor-1 (ESE-1), which is also known as E74-like factor-3 (Elf3) in mice, is strongly expressed in lung during fetal development and in certain lung cancers. The primary goal of the work presented in this thesis was to investigate whether ESE-1 is involved in regeneration of the injured lung epithelium by administering naphthalene to both wild-type (Elf3 +/+) and Elf3-deficient (Elf3 -/-) mice. However, optimal conditions for proper utilization of the naphthalene-induced lung injury model must first be established. Therefore, dose-response studies were initially conducted by administering three different doses of naphthalene to both male and female mice, as described in chapter 2. Although it is shown that the extent of naphthalene-induced Clara cell injury is dose-dependent in both male and female mice, female mice are more sensitive to naphthalene-induced injury than male mice independent of the dose. Furthermore, it is also demonstrated that these gender-dependent differences in naphthalene injury can subsequently influence downstream lung repair kinetics. In light of these findings, lung regeneration was examined in both sexes of both Elf3 +/+ and Elf3 -/- mice. As reported in chapter 3, the kinetics of bronchiolar epithelial cell proliferation and differentiation is delayed considerably in Elf3 -/- mice following naphthalene injury. Moreover, expression of transforming growth factor-beta type II receptor, which is a well-known transcriptional target gene of ESE-1 and is involved in the induction of epithelial cell differentiation, is significantly lower in the bronchiolar airway epithelium of Elf3 -/- mice as compared to Elf3 +/+ mice under steady-state conditions and during repair of naphthalene-induced damage. Collectively, these findings occur to a similar extent in both sexes of both Elf3 +/+ and Elf3 -/- mice, and suggest that ESE-1 plays an important role in regulating the kinetics of airway epithelial regeneration after acute lung injury.
178

Uroguanylin and cGMP signaling a pathway for regulating epithelial cell renewal in the intestine /

Wang, Yuan, January 2001 (has links)
Thesis (Ph. D.)--University of Missouri--Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 95-113). Also available on the Internet.
179

Remodeling of the pulmonary microenvironment controls transforming growth factor-beta activation and alveolar type II epithelial to mesenchymal transition

Dysart, Marilyn Markowski 08 June 2015 (has links)
Pulmonary fibrosis is a potentially deadly pathology characterized by excessive deposition of extracellular matrix (ECM), increased tissue stiffness, and loss of tissue structure and function. Recent evidence has suggested epithelial to mesenchymal transition (EMT), the transdifferentiation of an epithelial cell into a mesenchymal fibroblast, is one mechanism that results in the accumulation of myofibroblasts and excessive deposition of ECM. EMT is a highly orchestrated process involving the integration of biochemical signals from specific integrin mediated interactions with ECM proteins and soluble growth factors including TGFβ. TGFβ, a potent inducer of EMT, can be activated by cell contraction mediated mechanical release of the growth factor from a macromolecular latent complex. Therefore, TGFβ activity and subsequent EMT may be influenced by both the biochemical composition and biophysical state of the surrounding ECM. Based on these knowns it was first investigated how changes in the biochemical composition of the matrix and changes in tissue rigidity together modulate EMT due to changes in epithelial cell contraction and TGFβ activation. Here we show that integrin specific interactions with fibronectin (Fn) variants displaying both the RGD and PHSRN binding sites facilitate cell binding through α3β1 and α5β1 integrins, and that these interactions maintain an epithelial phenotype despite engagement of increased tissue rigidities. Conversely, Fn fragments that facilitate cell binding through αv integrins drive TGFβ activation and subsequent EMT even while engaging soft underlying substrates. Adding to the complexity of studying mechanisms that contribute to pulmonary fibrosis, is exposure of the lung to injuries from environmental particulates. Therefore, we investigated how EMT is altered in response to particulate matter (PM). Here we show that PM exposure further drives TGFβ activation, EMT, and increases intracellular levels of reactive oxygen species (ROS). Additionally, cells binding the ECM through α5β1 and α3β1 integrins only partially recover an epithelial phenotype, suggesting ROS may be a secondary driver of TGFβ and EMT. Taken together these results suggest dynamic changes to the ECM microenvironment are major contributors to the control of EMT responses and provide insights into the design of biomaterial-based microenvironments for control of epithelial cell phenotype.
180

Effects of bacterial toxins on calcium homeostasis in renal inflammation /

Söderblom, Tomas, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.

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