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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Inhibition of GM-CSF Production in Fibroblast-Monocyte Coculture by Prednisone and Effects of RHFM-CSF on Human Lung Fibroblasts

Fitzgerald, S. Matthew, Chi, David S., Lee, Steven A., Hall, Kenton, Krishnaswamy, Guha 01 January 2004 (has links)
Fibroblasts play a sentinel role in asthmatic disease. They are the main constituents of connective tissue and are increased in number in the asthmatic lung. They are also capable of secreting a diverse repertoire of cytokines and are able to be activated by pro-inflammatory cytokines and cell-cell contact. Previously we have reported that normal human lung fibroblasts (NHLF) can be activated by monocytes (U937) through cell-cell contact to produce GM-CSF. Here we show that GM-CSF production from NHLF activated by monocyte contact is inhibited by prednisone, a synthetic glucocorticoid used in the treatment of asthma. GM-CSF is an acidic glycoprotein that potentiates development of cells in the granulocyte and macrophage lineage and is secreted at sites of peripheral inflammation. The receptor for GM-CSF was found on NHLF by flow cytometry and was able to be up-regulated by interleukin (IL)-1 beta, tumor necrosis factor (TNF)-alpha and recombinant human (rh) GM-CSF. To test autocrine effects of GM-CSF on fibroblasts, rh GM-CSF was used in proliferation studies and was found to decrease fibroblast proliferation. Prednisone was used to block NF-kappaB activation and GM-CSF gene expression as well. These data indicate mechanism of action and treatment for cell-cell contact mediated inflammation of infiltrating monocytes with fibroblasts as seen in asthma and other diseases like graft versus host disease.
72

Impact du G-CSF sur le phénotype et les fonctions des cellules NK dans le cadre d’une immunothérapie post-allogreffe de cellules souches hématopoïétiques / Impaired functions and proliferation of NK cells from patient G-CSF mobilized leukapheresis

Xiong, Yu 27 July 2016 (has links)
Les cellules Natural Killer (NK) sont capables de lyser les cellules tumorales sans la nécessité de reconnaitre un antigène tumoral spécifique. Cette propriété leur confère un avantage par rapport aux lymphocytes T et les rend intéressantes à utiliser en tant que cellules effectrices pour l’immunothérapie adoptive. A ce jour, le potentiel thérapeutique des cellules NK n’a pas été complétement exploré notamment dans le contexte du traitement de la rechute post-allogreffe de cellules souches hématopoïétiques. Actuellement, les patients en rechute post-greffe sont traités avec des injections de lymphocytes du donneur (DLI) parfois issues de petites fractions du greffon de cellules souches hématopoïétiques congelées. Les cellules souches périphériques étant fréquemment utilisées comme source de cellules souches et parfois utilisées comme DLI, nous avons souhaité évaluer l’impact du G-CSF sur le phénotype et les fonctions des cellules NK présentes dans ces fractions. Dans cet objectif, nous avons comparé différentes sources de cellules NK isolées à partir de sang de donneurs sains, de sang mobilisé de donneurs sains ou de patients et observé l’évolution des différentes sous-populations de cellules NK issues de ces prélèvements au décours d’une expansion en présence d’IL-15. Nos résultats ont montré que l’administration de G-CSF diminuait la proportion de cellules NK CD56brightCD16+ au profit d’une population CD16-, diminuait la prolifération des cellules NK lors de l’expansion en culture, et modifiait les propriétés fonctionnelles des cellules NK. / The ability of natural killer (NK) cells to kill tumor cells without the need to recognize a tumor-specific antigen provides advantages over T cells and makes them appealing for a use as effectors for adoptive immunotherapy. However, the full therapeutic potential of NK cell-based immunotherapy has not been fully investigated in the context of leukemic relapse after hematopoietic stem cell transplantation. Today, patients relapsing after hematopoietic stem cell transplantation are often treated with donor lymphocyte infusion (DLI) based on small cell fractions frozen at the time of the stem cell transplantation. Since peripheral blood stem cells are increasingly used as stem cell source and as source of cells for DLI, we aimed to evaluate the impact of G-SCF mobilization on NK cell phenotype and functions. Therefore, we compared the expansion capacity, the phenotype and the function of NK cells from blood for healthy donors, from allogeneic HSCT healthy donors or from autologous HSCT from patients. We also determine the impact of G-CSF on NK cell subset repartition before and after expansion in presence of IL-15. Our results showed that G-CSF administration to patients decreases CD56brightCD16+ NK cell population, proliferation and function. Overcoming this impairment in lymphoid capacity may be important to facilitate post-transplant immunotherapy.
73

Hormonal regulation and promoter analysis of the follicle-stimulating hormone b-subunit gene (FSHb)of goldfish, carassius auratus.

January 2002 (has links)
Ko Nga Ling. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 98-131). / Abstracts in English and Chinese. / Abstract (in English) --- p.ii / Abstract (in Chinese) --- p.v / Acknowledgements --- p.vii / Table of Contents --- p.ix / List of Figures --- p.xiv / List of Tables --- p.xvii / Symbols and Abbreviations --- p.xviii / Scientific Names --- p.xxi / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Gonadotropins --- p.1 / Chapter 1.1.1 --- Structure --- p.1 / Chapter 1.1.2 --- Function --- p.3 / Chapter 1.1.3 --- Regulation --- p.5 / Chapter 1.1.3.1 --- Hypothalamic regulators (GnRH) --- p.5 / Chapter 1.1.3.2 --- Endocrine regulators from gonads (steroids) --- p.7 / Chapter 1.1.3.3 --- Paracrine regulators (activin) --- p.9 / Chapter 1.1.4 --- Promoter analysis --- p.9 / Chapter 1.2 --- Activin Family of Growth Factors --- p.12 / Chapter 1.2.1 --- Activin --- p.12 / Chapter 1.2.1.1 --- Structure --- p.12 / Chapter 1.2.1.2 --- Function --- p.13 / Chapter 1.2.1.3 --- Signaling --- p.15 / Chapter 1.2.2 --- Follistatin --- p.16 / Chapter 1.2.2.1 --- Structure --- p.16 / Chapter 1.2.2.2 --- Function --- p.17 / Chapter 1.3 --- Objectives --- p.18 / Chapter Chapter 2 --- Establishment and Characterization of Stable LβT2 Cell Lines Containing and Expressing SEAP Driven by the Goldfish FSHβ Promoter / Chapter 2.1 --- Introduction --- p.29 / Chapter 2.2 --- Materials and Methods --- p.31 / Chapter 2.2.1 --- Construction of expression plasmid --- p.31 / Chapter 2.2.2 --- Cell culture --- p.32 / Chapter 2.2.3 --- Cotransfection of LβT2 cells --- p.32 / Chapter 2.2.4 --- G418 selection of transfected LpT2 cells --- p.33 / Chapter 2.2.5 --- SEAP reporter gene assay --- p.33 / Chapter 2.2.6 --- Cloning of pSEAP/gfFSHβ promoter and pBK- CMV-transfected LβT2 cells by limited dilution --- p.34 / Chapter 2.2.7 --- Extraction of genomic DNA --- p.34 / Chapter 2.2.8 --- Isolation of total RNA --- p.35 / Chapter 2.2.9 --- Reverse transcription-polymerase chain reaction (RT-PCR) --- p.35 / Chapter 2.3 --- Results --- p.36 / Chapter 2.3.1 --- Optimization of G418 concentration for selection --- p.36 / Chapter 2.3.2 --- Expression of SEAP reporter gene by pSEAP/gfFSHβ promoter and pBK-CMV-transfected LβT2 cells --- p.37 / Chapter 2.3.3 --- Establishment of LβT2 cell lines that contain a functional gfFSHp promoter --- p.37 / Chapter 2.3.4 --- Characterization of LβT2#23 that contains a functional gfFSHβ promoter --- p.38 / Chapter 2.4 --- Discussion --- p.39 / Chapter Chapter 3 --- Hormonal Regulation of Goldfish Follicle-Stimulating Hormone β (FSHβ) Promoter Activity in LpT2#23 Cells / Chapter 3.1 --- Introduction --- p.52 / Chapter 3.2 --- Materials and Methods --- p.54 / Chapter 3.2.1 --- Cell culture --- p.55 / Chapter 3.2.2 --- Drug treatment --- p.56 / Chapter 3.2.3 --- SEAP reporter gene assay --- p.56 / Chapter 3.2.4 --- Isolation of total RNA --- p.57 / Chapter 3.2.5 --- Reverse transcription-polymerase chain reaction (RT-PCR) --- p.57 / Chapter 3.2.6 --- Data analysis --- p.58 / Chapter 3.3 --- Results --- p.59 / Chapter 3.3.1 --- Effects of goldfish activin on FSHβ promoter --- p.59 / Chapter 3.3.2 --- Blockade of activin effects by follistatin --- p.59 / Chapter 3.3.3 --- Effects of different hormones and steroids on FSHβ promoter --- p.60 / Chapter 3.4 --- Discussion --- p.61 / Chapter Chapter 4 --- Promoter Analysis for the Activin Responsive Element (ARE) in the Goldfish Follicle-Stimulating Hormone β (FSHβ) Gene / Chapter 4.1 --- Introduction --- p.71 / Chapter 4.2 --- Materials and Methods --- p.74 / Chapter 4.2.1 --- Generation of SEAP reporter plasmids containing the gfFSHβ promoter of different lengths --- p.74 / Chapter 4.2.2 --- PCR screening and restriction analysis --- p.75 / Chapter 4.2.3 --- Midiprep --- p.76 / Chapter 4.2.4 --- Cell culture --- p.77 / Chapter 4.2.5 --- Transfection of the pSEAP/gfFSHβ promoter constructs into LβT2 cells --- p.77 / Chapter 4.2.6 --- Activin treatment --- p.77 / Chapter 4.2.7 --- SEAP assay --- p.78 / Chapter 4.3 --- Results --- p.78 / Chapter 4.3.1 --- Subcloning of the gfFSHβ promoter of decreasing length into SEAP reporter vector --- p.78 / Chapter 4.3.2 --- Activin stimulation of the pSEAP/gfFSHβ promoter constucts in LβT2 cells --- p.79 / Chapter 4.4 --- Discussion --- p.80 / Chapter Chapter 5 --- General Discussion / Chapter 5.1 --- Overview --- p.92 / Chapter 5.2 --- Contribution of the present research --- p.95 / Chapter 5.2.1 --- Establishment of stable LβT2 cell lines containing and expressing SEAP driven by gfFSHβ promoter --- p.95 / Chapter 5.2.2 --- Hormonal regulation of the gfFSHβ promoterin LβT2#23 cells --- p.95 / Chapter 5.2.3 --- Identification of the activin responsive element (ARE) on the gfFSHβ promoter --- p.96 / Chapter 5.3 --- Future research direction --- p.96 / References --- p.98
74

Evaluation von Granulozyten Kolonie-stimulierendem Faktor (G-CSF) und einem monoklonalen Antikörper gegen Kapselpolysaccharid zur Therapie der experimentellen Klebsiella pneumoniae-Pneumonie / direkte Interaktion des hämatopoetischen Wachstumsfaktors mit dem Bakterium steigert dessen Virulenz

Held, Thomas 20 June 2001 (has links)
G-CSF besitzt direkte Effekte auf die Aktivierung bakterizider Eigenschaften neutrophiler Granulozyten und verbessert das Überleben bakteriell infizierter Tiere. Daher wurde in der hier vorliegenden Arbeit der Effekt einer prophylaktischen oder therapeutischen Gabe von G-CSF bei experimenteller Pneumonie durch Klebsiella pneumoniae in Mäusen untersucht. Unerwarteterweise verschlechterte aber eine prophylaktische G-CSF-Gabe das Überleben und führte dosisabhängig zu einer Steigerung der bakteriellen Dissemination von der Lunge in Leber und Milz. Im Gegensatz dazu konnte ein spezifisch gegen K2-Kapselpolysaccharid (K2-KPS) von K. pneumoniae gerichteter monoklonaler Antikörper signifikant die Vermehrung der Bakterien in Lunge, Leber und Milz reduzieren. Die Blockierung von TNF?? durch Pentoxifyllin hingegen verzögerte die Letalität nach Induktion der Pneumonie, verhinderte sie jedoch nicht. In vitro konnte hier nachgewiesen werden, daß G-CSF spezifisch an K. pneumoniae bindet und daß diese Bindung an mehrere Proteine mit einem Molekulargewicht von 41, 25 und 21 kDa erfolgt. Die Bindung von G-CSF an K. pneumoniae führte zu einer signifikant erhöhten Produktion des wichtigsten Virulenzfaktors, K2-KPS. Dies verminderte in vitro signifikant eine Phagozytose der Bakterien durch neutrophile Granulozyten. Damit gelang es zum ersten Mal, die Bindung von G-CSF an ein gram-negatives Bakterium, K. pneumoniae, nachzuweisen und zu zeigen, daß diese Bindung in vitro zu einer erhöhten Produktion des wichtigsten Virulenzfaktors und in vivo zur Verschlechterung einer experimentellen Pneumonie durch erhöhte bakterielle Disseminierung bei prophylaktischer Gabe von G-CSF vor Infektion führt. Die weitere Untersuchung dieser Phänomene hinsichtlich einer möglichen Bindung von G-CSF auch an andere Bakterien könnte zu einer differenzierten supportiven Therapie bakterieller Infektionen mit G-CSF in nicht neutropenischen Patienten führen. / Besides its well-established effects on granulocytopoiesis, granulocyte colony-stimulating factor (G-CSF) has been shown to have direct effects on the recruitment and bactericidal ability of neutrophils, resulting in improved survival of experimentally infected animals. The effect of G-CSF on the course of experimental pneumonia induced by Klebsiella pneumoniae was studied. Using a highly reproducible murine model, the paradoxical finding that mortality from infection was significantly increased when animals received G-CSF before induction of pneumonia could be demonstrated. Administration of G-CSF promoted replication of bacteria in the liver and spleen, thus indicating an impairment rather than an enhancement of antibacterial mechanisms. By contrast, a monoclonal antibody against Klebsiella K2 capsule significantly reduced bacterial multiplication in the lung, liver, and spleen, and abrogated the increased mortality caused by G-CSF. Blocking of TNF-? with pentoxifylline, however, could not prevent increased mortality caused by G-CSF. In vitro studies showed a direct effect of G-CSF on K pneumoniae resulting in inreased capsular polysaccharide (CPS) production. When bacteria were coincubated with therapeutically achievable concentrations of G-CSF, phagocytic uptake and killing by neutrophils was impaired. Western blot analysis showed three binding sites of G-CSF to K pneumoniae. Thus, in this model, the direct effect of G-CSF on a bacterial virulence factor, CPS production, outweighed any beneficial effect of G-CSF on recruitment and stimulation of leukocytes. Further investigations of possible binding of G-CSF to other bacteria might influence a differentiated supportive therapy of bacterial infections in non-neutropenic patients with this growth factor.
75

Neuroprotective effects of granulocyte-colony stimulating factor in a mice stroke model

Chan, Chu-fung., 陳柱峰. January 2007 (has links)
published_or_final_version / Medicine / Master / Master of Philosophy
76

A Burkeian Analysis of the Rhetoric of Rebirth in Selected Television Commercials

Thetford, Tony R. 05 1900 (has links)
The purpose of this study was to analyze the content of selected television commercials according to Kenneth Burke's theory of the rhetoric of rebirth. A supplementary Burkeian method called cluster analysis was also used. The analysis revealed, that the rhetoric of rebirth was incorporated in the commercials to stimulate guilt in the television audience. The products offered in the commercials supposedly purged this guilt, transforming the person to a new way of life. The analysis revealed meanings inherent in the word choices for various commercials as well as the potential impact of those words. The study isolated several underlying motifs in the substance of the commercials. The effect of the visual message may cause the audience to overlook the message of the words. Experimental research cited in this study confirms this hypothesis.
77

The flushing effect and expression of follicle stimulating hormone receptor rariants in sheep.

Hand, Jacqelyn M. January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Timothy G. Rozell / Timothy G. Rozell / An increase in pre-mating dietary energy positively influences ovulation and lambing rates, and this practice is known as nutritional flushing. The mechanisms of flushing, however, are still unknown. Increasing dietary energy approximately two weeks before breeding likely increases the production of insulin-like growth factor I (IGF-I) within the ovary, which stimulates the synthesis of follicle stimulating hormone receptor (FSHR). Several alternatively spliced transcripts of the FSHR have been identified in sheep. Each variant form is believed to be produced according to the stage of follicle development. This study was carried out to evaluate expression patterns of the FSHR variant forms (FSHR-1, FSHR-2 and FSHR-3) in the sheep ovary in response to different flushing diets. For this experiment, yearling Rambouillet ewes (n=93) were allocated among 6 different energy type treatment diets, either prairie or alfalfa hay based, for at least two weeks in combination with the insertion of a controlled internal drug releasing device (CIDR). Two of the treatment groups had commercially available block supplements provided and two had rolled corn supplemented. Mid-ventral laparotomy was performed on each ewe 3.5 to 4 days after CIDR removal. Follicles 4 mm and greater were aspirated and categorized as either medium (M; 4 to 6 mm) or large (L; > 6 mm). Total RNA was extracted from granulosa cells (GC) and reverse transcribed followed by qPCR of the resulting cDNA using specifically designed primer sets for each variant of the FSHR and for the LH receptor. Changes in live weight were different (P < 0.01) between treatment diets but there were no statistical differences for NEFA concentrations between any of the treatments nor were there differences for body condition (mean = 3.0) or lambing rate. Therefore, it is likely a flushing response did not occur in this study. Expression of FSHR-1was different between M and L follicles (P < 0.01) and tended to be different for ewes fed alfalfa hay (P = 0.05). Overall mean expression of FSHR-3 was greater than expression of FSHR-1 or FSHR-2 (P < 0.01), although there was no difference between M and L follicles, or between treatment diets. The concentration of estradiol in follicular fluid was not different between the treatment diets or follicle sizes nor was expression of lutenizing hormone receptor (LHR), indicating that follicles were similar developmentally. The FSHR-1 form seemed to be the variant most likely to be involved in later stages of follicular development, and is potentially involved in follicle rescue. For all follicles, FSHR-3 was the more highly expressed form of the FSHR and may likely be essential throughout antral follicle development. Further research is required to determine the exact mechanism whereby initial energy status of ewes seems critical for the increased ovulation rate that occurs after energy supplementation (i.e. the flushing response).
78

Relação da concentração do hormônio antimulleriano com população folicular e fertilidade em fêmeas bovinas /

Pupulim, Antônio Guilherme Roncada. January 2013 (has links)
Orientador: Ciro Moraes Barros / Banca: Ronaldo Luiz Ereno / Banca: João Carlos Ferreira / Resumo: O crescimento folicular em bovinos ocorre em um padrão de ondas que pode variar de 2 a 3 por ciclo estral e caracteriza-se pelo crescimento sincrônico de um grupo de folículos antrais, onde apenas um se tornará dominante. A quantidade de folículos recrutados é variável entre os animais, porém apresenta alta repetibilidade entre os indivíduos. Animais Bos indicus apresentam maior quantidade de folículos recrutados por onda que animais Bos taurus. Objetivou-se com o presente trabalho, (1) identificar fêmeas das raças Nelore (Bos indicus) e Aberdeen Angus (Bos taurus), que possuam elevado ou reduzido número de folículos recrutados por onda e relacionar o número de folículos à concentração plasmática do hormônio anti-mulleriano (AMH); (2) relacionar o numero de folículos antrais à fertilidade de fêmeas Nelore e; (3) determinar se o tratamento superestimulatório altera as concentrações plasmáticas de AMH em vacas Nelore. No experimento 1, contagem do numero de folículos antrais das fêmeas Nelore (n=20) e Angus (n=30) foi feita por duas avaliações ultrassonográficas (US). Considerando a média  EPM da contagem de folículos antrais de cada raça, as novilhas foram classificas em alta contagem folicular (ACF; n= 9 novilhas Nelore e 15 Angus) ou baixa contagem folicular (BCF; n= 11 novilhas Nelore e 15 Angus). O AMH foi mensurado por Elisa em uma amostra de sangue coletada durante a ultima US. No experimento 2, foram utilizadas novilhas da raça Nelore (n=86) submetidas a um protocolo de inseminação artificial em tempo fixo (IATF). As novilhas foram classificadas (avaliação US no D0 da IATF) em 3 grupos: ACF (>40 folículos; n=29), intermediário (ICF;>20 e <40 folículos; n=34) e BCF (<20 folículos; n=23). No experimento 3, foram utilizadas 20 vacas da raça Nelore de ICF e ACF. Os animais foram separados pela contagem folicular e distribuídos em 2 grupos: Grupo controle IATF (n=9) e grupo P36 (superestimuladas ... / Abstract: In bovines follicular development happens in a wave pattern that can vary from two to three waves per estral cycle with a group of follicles growing simultaneously but with only ano becoming the dominat follicle. The number of recruited follicle is highly variable between animal; however it is highly repeatable within an animal. Bos indicus animals present greater number of follicles per wave than Bos taurus animals. The objective of the present study was 1) identify animals from the Nelore and Abeerden Angus breed that have high or low number of follicles recruited per follicle wave and relate the number of follicles with AMH concentration; 2) to relate the number of antral follicles with the fertility of Nelore females; 3) to determine if the superstimulatory treatment alters the plasmatic concentrations of AMH. In experiment 1 the follicle count in Nelore and Angus heifers was done through two ultrasound examinations (US). Considering the mean + SEM of the follicle count in each breed, the heifers were grouped in high (HFC) or low (LFC) follicle count. Plasmatic AMH was measured in a blood smple drawn at the last US. In Experiment 2, there were used Nelore heifers submitted to a TFAI protocol. Heifers were grouped in HFC (>40 follicles), intermediary (>20 an <40 follicle) and LFC (<20 follicle). In experiment 3, Nelore cows with high and intermediary follicles counts were used. Animals were separated in control TFAI group and P36 group. Blood samples for AMH measurement were collected on day 5 (P36) and on day 8 (TFAI and P36). Result from experiment 1 were analyzed using ANOVA. Experiment 2 was analyzed using a logistic regression and experiment 3 was ... / Mestre
79

Expression control of zebrafish gonadotropin receptors in the ovary. / CUHK electronic theses & dissertations collection

January 2012 (has links)
卵泡刺激素(FSH)和促黃體激素(LH)是脊椎動物體內的促性腺激素(GTH)。它們通過其相應的GTH受體(GTHR)- FSH受體(FSHR)及LH/絨毛膜性腺激素受體(LHCGR),來調控雌性脊椎動物的主要性腺活動,如卵泡生成和類固醇生成。因此,GTHR的表達水平可控制卵泡細胞對於GTH的反應程度,從而影響脊椎動物的繁殖能力。 / 然而,跟哺乳動物中的資料相比,這些受體的表達調控機制在硬骨魚類中仍然很模糊。此前,我們已經證明了斑馬魚卵泡之fshr和lhcgr的表達譜差異,顯示出lhcgr的表達滯後於fshr的表達。此表達時間之差異引申出兩條有趣的問題:一)甚麼激素能分別調節fshr和lhcgr的表達? 二)這些調控的機制是甚麼?因此,我們發起本研究來解答這些問題。 / 利用培養出來的斑馬魚卵泡細胞,我們展示了雌二醇(E2)是一個有力的GTHR調控激素。雖然E2同時刺激了fshr和lhcgr的表達,但E2對於lhcgr的表達調控效力遠遠比對fshr的高。由於雌激素核受體(nER)的特異拮抗劑(ICI 182,780)能完全抵消E2的效果,表明了E2是通過傳統的nER來直接促進了lhcgr的表達。有趣的是,不能穿越細胞膜的雌二醇-牛血清白蛋白偶聯複合物(E2-BSA)能完全模仿E2的效果,因此我們的證據提出這些nER可能位於細胞膜上。此外,我們運用各種藥劑發現了多種信號分子跟E2調控GTHR的能力有關,包括cAMP、PKA、PI3K、PKC、MEK、MAPK及p38 MAPK。當中以cAMP-PKA的信號傳導最有可能在E2的雙相調控效果起了直接作用,而E2的行動也極依賴其他信號分子的允許作用。 / 除了E2,人絨毛膜促性腺激素(hCG; LH的類似物)、垂體腺苷酸環化酶激活多肽(PACAP)、表皮生長因子(EGF)和胰島素樣生長因子-I(IGF-I)也能有效地調節斑馬魚卵泡細胞的GTHR表達。hCG能大幅下調其受體lhcgr的表達,顯示hCG能令卵泡細胞對GTH脫敏。與此同時,PACAP能瞬時模仿hCG的行動,表明了PACAP很可能是hCG的瞬態下游信號。EGF是一個強烈抑制lhcgr表達的因子,而IGF-I是一個潛在的fshr表達增強因子,均說明了旁分泌因子對GTHR表達調控有關鍵作用。除了這些激素或因子的獨立調控作用,我們進一步發現了E2的效果可能會被它們覆蓋或調節。它們對nER的調控作用可能會造成這種現象。PACAP瞬時減少了esr2a及esr2b的表達量,而EGF則顯著地下調了esr2a。 / 作為第一個在硬骨魚卵巢中對GTHR調控的全面研究,它無疑豐富了我們對卵泡生成過程中GTH的功能及GTHR表達調控的認識。此外,我們成功將目前的研究平台應用於雙酚A(BPA)的研究,進一步展示了本研究平台的潛力,有助於我們未來對各種內分泌干擾物(EDC)的作用機制進行研究。 / Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are the gonadotropins (GTHs), which bind to their cognate GTH receptors (GTHRs), FSH receptor (FSHR) and LH/choriogonadotropin receptor (LHCGR), to mediate major gonadal events in female vertebrates, including folliculogenesis and steroidogenesis. The expression level of GTHRs, therefore, controls the responsiveness of follicle cells to GTHs and hence governs the vertebrate reproduction. / However, compared with the information in mammals, the expression control of these receptors in teleosts remains largely unknown. Previously, we have demonstrated the differential expression profiles of fshr and lhcgr in the zebrafish folliculogenesis, showing that lhcgr expression lags behind fshr expression. This temporal difference between fshr and lhcgr expression has raised two interesting questions: 1) What hormones regulate the differential expression of fshr and lhcgr? and 2) What are the control mechanisms of these regulations? The present study was initiated to answer these questions. / With the primary zebrafish follicle cell cultures, we demonstrated that estradiol (E2) was a potent differential regulator of GTHRs. Although E2 increased both fshr and lhcgr expression, the up-regulatory potency of E2 on lhcgr was much greater than that on fshr. E2 directly promoted lhcgr expression via classical nuclear estrogen receptors (nERs) since nER-specific antagonist (ICI 182,780) completely abolished the E2 effect. Interestingly, our evidence suggested that these nERs could be localized on the plasma membrane because the membrane-impermeable form of estrogen (E2-BSA) fully mimicked the actions of E2. Furthermore, by applying various pharmaceutical agents, we revealed the involvement of multiple signaling molecules, including cAMP, PKA, PI3K, PKC, MEK, MAPK and p38 MAPK. The cAMP-PKA pathway likely played a direct role in the biphasic actions of E2 while the E2 actions were also greatly dependent on the permissive actions of other signaling molecules. / Apart from the sex steroid E2, human chorionic gonadotropin (hCG; as a LH analogue), pituitary adenlyate cyclase-activating peptide (PACAP), epidermal growth factor (EGF) and insulin-like growth factor-I (IGF-I) also significantly regulated GTHR expression in the zebrafish follicle cells. hCG drastically down-regulated its receptor, lhcgr, suggesting that hCG could desensitize the follicle cells to respond to GTH. Meanwhile, PACAP transiently mimicked the actions of hCG, indicating that PACAP was likely a transient downstream mediator of hCG. EGF was another strong suppressor of lhcgr expression while IGF-I was a potential fshr expression enhancer, which highlighted the crucial roles of paracrine factors in the regulation of GTHRs. In addition to the regulatory effect of these individual hormones or factors, we further revealed that the E2 action could be overridden or modulated by them. Their regulatory effects on the expression of nERs might contribute to this phenomenon. PACAP transiently reduced esr2a and esr2b expression while EGF significantly down-regulated esr2a. / As the first comprehensive study of GTHR regulation in the teleost ovary, the present study certainly enriched our knowledge in the functions of GTHs and the expression control of GTHRs during folliculogenesis. By applying the current research platform on the study of bisphenol A (BPA), an endocrine-disrupting chemical (EDC), the present study further highlighted the potential of this research platform to contribute to the future action mechanism studies of various EDCs. / 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. / Liu, Ka Cheuk. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 159-212). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Abstract (in English) --- p.i / Abstract (in Chinese) --- p.iii / Acknowledgement --- p.v / Table of contents --- p.vi / List of figures and tables --- p.xii / Symbols and abbreviations --- p.xv / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Hypothalamic-pituitary-gonadal axis / Chapter 1.1.1 --- Overview --- p.1 / Chapter 1.1.2 --- Gonadotropin-releasing hormone --- p.1 / Chapter 1.2 --- Folliculogenesis / Chapter 1.2.1 --- Structure of ovarian follicles --- p.2 / Chapter 1.2.2 --- Stages of folliculogenesis --- p.3 / Chapter 1.3 --- Gonadotropins and gonadotropin receptors / Chapter 1.3.1 --- History of teleost gonadotropin and gonadotropin receptors --- p.5 / Chapter 1.3.2 --- Structure --- p.6 / Chapter 1.3.3 --- Function --- p.7 / Chapter 1.3.4 --- GTH-GTHR specificity --- p.9 / Chapter 1.3.5 --- Signal transduction --- p.10 / Chapter 1.3.6 --- Expression profile of gonadotropin receptors --- p.11 / Chapter 1.3.7 --- Regulation of gonadotropin receptors --- p.12 / Chapter 1.4 --- Objectives and significances of the project --- p.14 / Chapter 1.5 --- Figure legends --- p.16 / Chapter 1.6 --- Figures --- p.18 / Chapter Chapter 2 --- Differential Regulation of Gonadotropin Receptors (fshr and lhcgr) by Estradiol in the Zebrafish Ovary Involves Nuclear Estrogen Receptors That Are Likely Located on the Plasma Membrane / Chapter 2.1 --- Introduction --- p.24 / Chapter 2.2 --- Materials and methods / Chapter 2.2.1 --- Animals --- p.25 / Chapter 2.2.2 --- Hormones and chemicals --- p.26 / Chapter 2.2.3 --- Primary follicle cell culture and drug treatment --- p.26 / Chapter 2.2.4 --- Ovarian fragment incubation --- p.27 / Chapter 2.2.5 --- Total RNA extraction and real-time qPCR --- p.27 / Chapter 2.2.6 --- Western blot analysis --- p.27 / Chapter 2.2.7 --- SEAP reporter gene assay --- p.28 / Chapter 2.2.8 --- Data analysis --- p.28 / Chapter 2.3 --- Results / Chapter 2.3.1 --- Differential stimulation of fshr and lhcgr expression in ovarian fragments and follicle cells by estradiol but not testosterone --- p.28 / Chapter 2.3.2 --- Potentiation of follicle cell responsiveness to hCG by E2 pretreatment --- p.30 / Chapter 2.3.4 --- Evidence for transcription but not translation-dependent up-regulation of lhcgr by E2 --- p.30 / Chapter 2.3.5 --- Evidence for the involvement of nuclear estrogen receptors but not G protein-coupled estrogen receptor 1 (Gper) in E2-stimulated lhcgr expression --- p.31 / Chapter 2.3.6 --- Evidence for possible localization of estrogen receptors on the plasma membrane --- p.32 / Chapter 2.3.7 --- MAPK dependence of E2 effect on lhcgr expression --- p.32 / Chapter 2.4 --- Discussion --- p.33 / Chapter 2.5 --- Table --- p.38 / Chapter 2.6 --- Figure legends --- p.39 / Chapter 2.7 --- Figures --- p.43 / Chapter Chapter 3 --- Signal Transduction Mechanisms of the Biphasic Estrogen Actions in the Regulation of Gonadotropin Receptors (fshr and lhcgr) in the Zebrafish Ovary / Chapter 3.1 --- Introduction --- p.50 / Chapter 3.2 --- Materials and methods / Chapter 3.2.1 --- Animals --- p.52 / Chapter 3.2.2 --- Hormones and chemicals --- p.52 / Chapter 3.2.3 --- Primary cell culture and drug treatment --- p.52 / Chapter 3.2.4 --- Total RNA extraction and real-time qPCR --- p.52 / Chapter 3.2.5 --- Fractionation of follicle cells --- p.52 / Chapter 3.2.6 --- Western blot analysis --- p.52 / Chapter 3.2.7 --- Statistical analysis --- p.53 / Chapter 3.3 --- Results / Chapter 3.3.1 --- Biphasic roles of cAMP-PKA pathway --- p.53 / Chapter 3.3.2 --- Effects of p38 MAPK inhibition --- p.54 / Chapter 3.3.3 --- Effects of PKC and PI3K inhibition --- p.54 / Chapter 3.4 --- Discussion --- p.55 / Chapter 3.5 --- Figure legends --- p.59 / Chapter 3.6 --- Figures --- p.61 / Chapter Chapter 4 --- Gonadotropin (hCG) and pituitary adenylate cyclase-activating peptide (PACAP) down-regulate basal and E2-stimulated gonadotropin receptors (fshr and lhcgr) in the zebrafish ovary via a cAMP-dependent but PKA-independent pathway / Chapter 4.1 --- Introduction --- p.66 / Chapter 4.2 --- Materials and methods / Chapter 4.2.1 --- Animals --- p.69 / Chapter 4.2.2 --- Hormones and chemicals --- p.69 / Chapter 4.2.3 --- Primary cell culture and drug treatment --- p.69 / Chapter 4.2.4 --- Total RNA extraction and real-time qPCR --- p.69 / Chapter 4.2.5 --- Statistical analysis --- p.69 / Chapter 4.3 --- Results / Chapter 4.3.1 --- Down-regulation of fshr and lhcgr by hCG --- p.69 / Chapter 4.3.2 --- Differential regulation of fshr and lhcgr by PACAP --- p.70 / Chapter 4.3.3 --- Inhibition of E2-regulated fshr and lhcgr expression by hCG --- p.71 / Chapter 4.3.4 --- Suppressive effects of PACAP on E2-induced fshr and lhcgr expression --- p.71 / Chapter 4.3.5 --- Role of cAMP in hCG and PACAP actions --- p.72 / Chapter 4.4 --- Discussion --- p.73 / Chapter 4.5 --- Figure legends --- p.78 / Chapter 4.6 --- Figures --- p.80 / Chapter Chapter 5 --- Paracrine regulation of gonadotropin receptors (fshr and lhcgr) by ovarian growth factors: epidermal growth factor (EGF) and insulin-like growth factor-I (IGF-I) / Chapter 5.1 --- Introduction --- p.85 / Chapter 5.2 --- Materials and methods / Chapter 5.2.1 --- Animals --- p.88 / Chapter 5.2.2 --- Hormones and chemicals --- p.88 / Chapter 5.2.3 --- Primary cell culture and drug treatment --- p.88 / Chapter 5.2.4 --- Total RNA extraction and real-time qPCR --- p.88 / Chapter 5.2.5 --- Statistical analysis --- p.88 / Chapter 5.3 --- Results / Chapter 5.3.1 --- Biphasic down-regulation of lhcgr by EGF --- p.89 / Chapter 5.3.2 --- Evidence for EGFR involvement --- p.89 / Chapter 5.3.3 --- Minor role of MEK-MAPK3/1 pathway in the EGF effect on lhcgr expression --- p.90 / Chapter 5.3.4 --- Up-regulation of fshr by IGF-I --- p.90 / Chapter 5.3.5 --- Evidence for IGF-IR involvement --- p.91 / Chapter 5.3.6 --- Role of PI3K-Akt pathway in IGF-I action --- p.91 / Chapter 5.3.7 --- Role of EGF and EGFR in E2-induced GTHR expression --- p.91 / Chapter 5.3.8 --- Role of IGF-I and IGF-IR in E2-induced GTHR expression --- p.91 / Chapter 5.4 --- Discussion --- p.92 / Chapter 5.5 --- Figure legends --- p.98 / Chapter 5.6 --- Figures --- p.100 / Chapter Chapter 6 --- Regulation of estrogen receptor subtypes (esr1, esr2a and esr2b): a possible mechanism to modulate estradiol-stimulated lhcgr expression in the zebrafish ovary / Chapter 6.1 --- Introduction --- p.107 / Chapter 6.2 --- Materials and methods / Chapter 6.2.1 --- Animals --- p.110 / Chapter 6.2.2 --- Hormones and chemicals --- p.110 / Chapter 6.2.3 --- Staging ovarian follicles --- p.110 / Chapter 6.2.4 --- Primary cell culture and drug treatment --- p.110 / Chapter 6.2.5 --- Total RNA extraction and real-time qPCR --- p.110 / Chapter 6.2.6 --- Statistical analysis --- p.111 / Chapter 6.3 --- Results / Chapter 6.3.1 --- Expression profiles of estrogen receptors (ERs) in zebrafish folliculogenesis --- p.111 / Chapter 6.3.2 --- Homologous regulation of nERs by E2 --- p.111 / Chapter 6.3.3 --- Regulation of nERs by endocrine hormones (hCG and PACAP) --- p.112 / Chapter 6.3.4 --- Regulation of nERs by ovarian paracrine growth factors (EGF and IGF-I) --- p.112 / Chapter 6.3.5 --- Role of cAMP in nER regulation --- p.113 / Chapter 6.3.6 --- Role of PKA in nER regulation --- p.113 / Chapter 6.4 --- Discussion --- p.114 / Chapter 6.5 --- Figure legends --- p.119 / Chapter 6.6 --- Figures --- p.121 / Chapter Chapter 7 --- Estrogenic Action Mechanisms of Bisphenol A / Chapter 7.1 --- Introduction --- p.127 / Chapter 7.2 --- Materials and methods / Chapter 7.2.1 --- Animals --- p.129 / Chapter 7.2.2 --- Hormones and chemicals --- p.129 / Chapter 7.2.3 --- Primary cell culture and drug treatment --- p.129 / Chapter 7.2.4 --- Total RNA extraction and real-time qPCR --- p.129 / Chapter 7.2.5 --- Statistical analysis --- p.130 / Chapter 7.3 --- Results / Chapter 7.3.1 --- Expression of fshr and lhcgr interfered by BPA --- p.130 / Chapter 7.3.2 --- Signaling mechanism of BPA-induced lhcgr up-regulation --- p.130 / Chapter 7.3.3 --- Dependence of transcription and translation in BPA-induced lhcgr expression --- p.131 / Chapter 7.3.4 --- Evidence for the involvement of nuclear estrogen receptors in the BPA actions --- p.131 / Chapter 7.3.5 --- Interference on E2-induced lhcgr expression by BPA --- p.131 / Chapter 7.4 --- Discussion --- p.132 / Chapter 7.5 --- Figure legends --- p.136 / Chapter 7.6 --- Figures --- p.138 / Chapter Chapter 8: --- General Discussion / Chapter 8.1 --- Estradiol as a differential regulator of gonadotropin receptors --- p.143 / Chapter 8.2 --- Conserved role of estradiol with differential action mechanisms in lhcgr regulation of mammals and teleosts --- p.144 / Chapter 8.3 --- Involvement of classical estrogen receptors that are likely located on the plasma membrane --- p.145 / Chapter 8.4 --- Biphasic response of lhcgr to estradiol and the underlying signal transduction mechanisms --- p.145 / Chapter 8.5 --- Desensitization of follicle cells to gonadotropins by hCG --- p.146 / Chapter 8.6 --- Paracrine control of gonadotropin receptors by ovarian growth factors --- p.147 / Chapter 8.7 --- Interaction of the estrogen action with other endocrine and paracrine signals --- p.148 / Chapter 8.8 --- Action mechanism studies of an endocrine-disrupting chemical: bisphenol A --- p.150 / Chapter 8.9 --- Conclusion --- p.151 / Chapter 8.10 --- Figure legends --- p.153 / Chapter 8.11 --- Figures --- p.155 / References --- p.159
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Use of Recombinant Human Granulocyte Colony Stimulating Factor as an Adjunct in Antifungal Chemotherapy in Various Animal Model Systems

Farrell, Lindi 01 May 1995 (has links)
The growing neutropenic patient population provides an ideal target for opportunistic fungal infections. Several effective antifungal drugs are toxic at high doses and contraindicated for long-term treatment. Recombinant human granulocyte colony stimulating factor (rhG-CSF) has been shown to increase neutrophilic numbers and functions, thus providing enhanced host defense. Improved efficacy by using rhG-CSF in conjunction with various antifungal agents was the primary focus of these studies. Use of rhG-CSF in a murine model of vaginal candidiasis did not reduce vaginal colony counts, or improve vaginal histophathology scores. Administration of rhG-CSF in a murine model of pulmonary aspergillosis improved survival, clinical signs, and gross pathology and histophathology scores of the lungs, and increased weight gain. The rhG-CSF was not shown to be an effective therapeutic treatment in this model of vaginal candidiasis. The rhG-CSF was, however, an effective prophylactic treatment in this model of pulmonary aspergillosis.

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