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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.
341

On the search for potential antihyperuricemic agents from natural products. / CUHK electronic theses & dissertations collection

January 2006 (has links)
Hyperuricemia is the hallmark of gout. Pathogenic mechanisms of hyperuricemia include uric acid overproduction in the liver or underexcretion in the kidney. Current antihyperuricemic agents include xanthine oxidase inhibitors in which allopurinol is the most often prescribed. Inhibitors of renal urate reabsorption such as probenecid and benzbromarone are also employed. However, these existing antihyperuricemic agents possess some undesirable effects such as hypersensitivity towards allopurinol and hepatotoxicity associated with benzbromarone. Therefore, search for alternative antihyperuricemic agents with a more favorable toxicological profile or via mechanisms other than the above two mentioned is highly warranted. / The present project represents such an effort. Four in vitro experimental models were developed for the screening of new antihyperuricemic agents. The effects of the potential compounds from natural sources on the activities of phosphoribosyl pyrophosphate synthetase, hypoxanthine-guanine phosphoribosyl transferase and xanthine oxidase, as well as the uptake of urate through rat renal brush border membrane vesicles were investigated. Several compounds emerged with strong urate uptake inhibitory activities in which morin (3, 5, 7, 2', 4'-pentahydroxyflavone) was the most potent. Interestingly some of these compounds including morin were also demonstrated to be xanthine oxidase inhibitors. The subsequent in vivo experiment showed that morin indeed exhibited hypouricemic and uricosuric actions in an acute oxonate-induced hyperuricemic rat model. The uricosuric action of morin was hirther studied in transfected HEK293 cells expressing the human urate anion transporter 1 (hURATI) which is believed to regulate blood urate level by mediating urate reabsorption. In hURAT1-expressing HEK293 cells, urate uptake was significantly increased as compared to the non-transfected parental cells. Incorporation of morin into the uptake buffer could dose-dependently inhibit urate uptake in the transfected cells. Taken together our data indicated that morin is a potentially useful antihyperuricemic agent which acts by inhibiting xanthine oxidase and inhibiting urate reabsorption. In addition, the favorable safety profile of this natural compound makes it a potential candidate worthy of further investigations. / Yu Zhifeng. / "June 2006." / Advisers: Christopher H. K. Cheng; Wing Ping Fong. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1584. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 155-169). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
342

Antitumor activities of ergosterol peroxide and 9,11-dehydroergosterol peroxide from Ganoderma lucidum mycelia. / CUHK electronic theses & dissertations collection

January 2009 (has links)
Ganoderma lucidum is one of most popular medicinal mushrooms in oriental countries. The medicinal properties of Ganoderma lucidum in the treatment of various diseases have been documented for hundreds of years. In recent years, more and more attentions are paid on the studies of the action mechanisms of bioactive compounds purified from this mushroom. / In conclusion, the Ganoderma steroids EP and 9(11)-DHEP can induce caspase-dependent apoptosis in susceptible cancer cells via the mitochondria-mediated pathway. In vitro and in vivo studies suggested that these two fungal steroids have the potential to be used as natural chemopreventive agents. / Keywords: Ergosterol peroxide, 9(11)-dehydroergosterol peroxide, Ganoderma lucidum, Mycelia, Antitumor activity, Apoptosis / The antiproliferative activities of EP and 9(11)-DHEP were studied by flow cytometry. Exposure of cancer cells with these two fungal steroids resulted in an accumulation of cell population at the subG1 phase in a dosage- and time-dependent manner, indicating the induction of apoptotic cell death. Morphological apoptotic changes in HepG2 cells and A375 cells were observed using TUNEL assay and Annexin-V-FLUOS assay. The signaling pathway in apoptotic cell death induced by EP and 9(11)-DHEP involved the activation of caspase 3, 7 and 9, followed by the cleavage of PARP. In Colo201 cells, a change in the ratio of expression levels of Bcl-2/Bax was observed in cells treated with EP and 9(11)-DHEP. In A375 cells, exposure to EP and 9(11)-DHEP resulted in the release of mitochondrial cytochrome c, the down-regulation of Mcl-1 and a slight up-regulation of Bak in a dosage-dependent manner. All these results indicated that apoptotic cell death in susceptible cancer cells induced by EP and 9(11)-DHEP was via the mitochondria-mediated pathway. / The in vivo antitumor activity of EP was demonstrated. EP was shown to suppress the growth of A375 cells in a nude mice xenograft model. Further studies showed that EP induced the cleavage of PARP and enhanced the total caspase 7 gene expression in the tumor cells. / Triterpenes and steroids are two important classes of Ganoderma lucidum metabolites of low molecular mass that are responsible for the antitumor activities of the mushroom. In this study, two fungal steroids, namely, 5alpha,8alpha-epidioxy-22E-ergosta-6,22-dien-3beta-ol (ergosterol peroxide (EP)) and 5alpha,8alpha-epidioxy-22E-ergosta-6,9(11),22-trien-3beta-ol (9,11-dehydroergosterol peroxide (9(11)-DHEP)) were purified from the mycelia of Ganoderma lucidum grown under submerged culture using activity-guided purification procedures against human breast adenocarcinoma MCF-7 cells. In addition to MCF-7 cells, both of these two fungal steroids showed antiproliferative activities against other human cancer cells including hepatocellular carcinoma HepG2 cells, colorectal carcinoma Colo201 cells, esophageal squamous carcinoma KYSE cells and malignant melanoma A375 cells. However, EP and 9(11)-DHEP were less toxic to MCF-10-2A, non-tumorigenic human epithelial cells, and the normal human skin fibroblast Hs68 cells. / Zheng, Lin. / Adviser: Y. S. Wong. / Source: Dissertation Abstracts International, Volume: 71-01, Section: B, page: 0253. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 153-176). / 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. / Abstracts in English and Chinese.
343

The antioxidative and hypolipidemic activities of hawthorn fruit. / CUHK electronic theses & dissertations collection

January 2001 (has links)
by Zhang Ze Sheng. / "October 2001." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (p. 157-174). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
344

Investigations on the antidiabetic actions of natural products using in vitro and in vivo systems. / CUHK electronic theses & dissertations collection

January 2006 (has links)
alpha-Glucosidase from yeast was used to screen for alpha-glucosidase inhibitory activities in Chinese herbal medicines. Seventy crude extracts were studied. The extracts of Semen Fagopyri Esculenti, Herba Euphorbiae Humifusae, Radix Polygoni Multiflori, Cortex Cinnamomi, Radix Paeoniae Rubra, and Radix Paeoniae Alba exhibited alpha-glucosidase inhibitory activities. These herbs have high potential for finding active compounds to develop into new antidiabetic drugs. / In this study, an assay technique involving brush border membrane vesicles was developed to screen for glucose uptake inhibitory actions in sixteen compounds from natural sources. Two compounds, namely naringenin and desoxyrhaponticin, were demonstrated to exhibit moderate inhibitory action on glucose uptake in rabbit intestinal brush border membrane vesicles, and showed very strong inhibitory action in rat everted intestinal sleeves. The kinetics study indicated that they behave as competitive inhibitors on glucose uptake. Moreover, they could reduce the level of the glucose uptake in the diabetic rat intestinal and renal membrane vesicles. In vivo study further demonstrated that desoxyrhaponticin could significantly reduce the glucose levels after a single oral administration of glucose in neonatal streptozotocin-induced diabetic rats, but not naringenin. These results suggest that naringenin and desoxyrhaponticin may be useful in the control of hyperglycemia. They act by inhibiting glucose uptake in the intestine and glucose reabsorption in the renal proximal tubules. / On the other hand, several synthetic compounds based on the structure of valienamine were found to show strong inhibition on intestinal alpha-glucosidases such as sucrase, glucoamylase and maltase. The strongest inhibitor was further studied. It could reduce the postprandial plasma glucose level of neonatal streptozotocin-induced diabetic rats. These results demonstrated that it has the potential to develop inter an oral antihyperglycemic agent. / The objective of this study is to improve the postprandial hyperglycemic conditions of diabetes by two approaches: (1) inhibiting the digestive enzymes (alpha-glucosidases), and (2) inhibiting active glucose transport in the small intestine. We have screened for new inhibitors of alpha-glucosidase and monosaccharide cotransporters from natural products and their derivatives. These compounds may be useful in the management of type 2 diabetes and diabetic complications. / Type 2 diabetes mellitus accounts for 90-95% of all diabetic cases and has become a major health concern over the world. There is increasing evidence that postprandial hyperglycemia, a hallmark of diabetes, plays a critical role in the development of type 2 diabetes and cardiovascular complications. Therefore the early identification of postprandial hyperglycemia and its effective control can offer the potential for early intervention and prevention of diabetic complications. / Li Jianmei. / "August 2006." / Adviser: Christopher H. K. Cheng. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1592. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 161-180). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
345

In vitro and in vivo studies on the anti-pancreatic cancer effects of Brucein D.

January 2013 (has links)
胰腺癌是一種死亡率極高的癌症, 據統計在所有的種族和性別中能達到五年存活的胰腺癌患者僅有5.5%。在現有醫學的治療方法中,除了手術切除之外,化學療法依然是主要的應對之策。接受胰腺癌切除術後的無瘤患者的生存期中位數和以現代一線化療藥吉西他濱治療的胰腺癌患者的生存期分別為13.4和6.9月。因此, 臨床上迫切需求更有效治療胰腺癌的新藥物。 / 我們從中藥鴉膽子中分離出了10種不同的化學單體。經過在人類胰腺癌細胞Capan-2上進行的細胞毒性篩選後, 發現Brucein D (BD)擁有最強的胰腺癌細胞毒性作用。我們目前的體外與體內實驗的目標是對BD可能具備的抗胰腺癌活性進行深入評估, 並進一步揭示其作用機理。 / 體外實驗研究表明BD可以極大程度上抑制Capan-2細胞生長, 同時對於人類肝細胞WRL68和人類胰腺幹細胞PPC僅存在很輕微的毒性作用。BD的抑制細胞生長作用和喜樹堿相當, 但顯著強於一線抗胰腺癌藥吉西他濱作。實驗中我們發現在BD作用的Capan-2細胞的線粒體膜電位被減弱, 其減弱程度與BD的濃度存在一定的劑量依賴性。另外, 被BD處理後的Capan-2細胞中的Bcl-2表達減弱, 與此同時capase 9和caspase 3的表達呈顯著性加強。除此之外, BD可以導致基因DNA破碎, 增加Capan-2細胞處於細胞凋亡期的數量, 而且處於凋亡期細胞的數量與BD存在劑量依賴性。 / 我們建立起原位型胰腺癌裸鼠模型並利用其進行體內實驗研究。研究結果顯示, BD治療組裸鼠的存活率遠遠大於吉西他濱治療組。此外, 與磷酸鹽緩衝鹽水注射組比較, BD治療組可以極大程度的減輕腫瘤的重量和減小腫瘤的體積。與此同時, 血液生化分析結果表明BD可以明顯降低CA19-9在血液中的表達。螢光免疫檢驗法結果揭示BD能夠調低CA19-9和Ki-67在胰腺腫瘤組織中的表達。蛋白質印記分析的結果也顯示BD治療後可以增強胰腺腫瘤組織中caspase 3, 8, 9的表達, 而減弱IKKα和NF-κB p65的表達。另外, 通過ELISA分析後顯示, BD治療明顯降低了NF-κB p65在細胞質與細胞核中的表達, 其表達程度與BD的濃度成反比。 / 綜上所述, 我們目前的體外和體內研究表明, BD作為一種存在于天然中藥中的化學單體具有很好的抗胰腺癌的潛質, 值得進一步研究和開發, 使之成為臨床治療胰腺癌的一種安全有效的新藥物。 / Pancreatic adenocarcinoma has a high morbidity and mortality rate in cancers as it possesses only 5.5% of 5-year survival rate for all races and both sexes. The median disease-free survival following complete resection of the pancreatic tumor and adjuvant chemotherapy with the first-line chemotherapeutic agent gemcitabine is 13.4 and 6.9 months, respectively. There issued an urgent need for alternative effective agents to producing a better clinical outcome for the management of this deadly disease. / Previous studies in our research group have shown that the fruit of Brucea javanica L. exhibited potent anti-pancreatic cancer activity. In the current project, ten chemical compounds were isolated from this Chinese herb and screened for their cytotoxicity against cultured Capan-2 cells, a human pancreatic adenocarcinoma cell line. Among these compounds, Brucein D (BD) exhibited the most potent cytotoxic activity. Further in vitro and in vivo studies were conducted to evaluate the potential anti-pancreatic cancer activity of BD and elucidate its underlying mechanisms of action. / In the In vitro study, BD was found to significantly inhibit the growth of Capan-2 cells, while exerting only modest cytotoxicity on human hepatocyte WRL68 cells and human pancreatic progenitor PPC cells. The anti-proliferative effects of BD were comparable to those exhibited by camptothecin and gemcitabine. We found a dose-dependent decrease of the mitochondrial membrane potential in BD-treated Capan-2 cells. In addition, BD exposure was able to attenuate the expression of Bcl-2 and significantly accentuate the expression of both caspase 9 and caspase 3. Moreover, BD was capable of inducing the fragmentation of genomic DNA while increasing the percentage of Capan-2 cells in the apoptotic phase and the quantity of apoptosis cells was observed in a dose- dependent manner. / A mouse model of orthotopic pancreatic cancer was established for the in vivo experiments. The results demonstrated that the BD-treated groups had a higher survival rate than that the gemcitabine-treated groups. Moreover, it was found that BD treatments significantly reduced the tumor weight and volume when compared with those of PBS injected group. Meanwhile, blood biochemistry analyses showed that BD significantly decreased the expression of CA19-9 (a tumor mark). Immunofluorescence study also revealed that BD could down-regulate the expression of both CA19-9 and Ki-67 in pancreatic tumor tissues. Furthermore, Western blot analysis showed that BD treatments could accentuate the expression of caspases 3, 8, 9 and decreased the expression of IKKα and NF-κB p65 in total. Moreover, BD attenuated the expression of NF-κB p65 in both cytoplasmic and nuclear factions of the tumor tissues as detected by ELISA kit, and the expression rate was inversely proportional to the doses of BD used. / Taken these data together, our in vitro and in vivo studies have successfully demonstrated that BD, a naturally occurring chemical compound from Fructus Bruceae, is a promising anti-pancreatic cancer agent worthy of further development into pharmaceutical agent for pancreatic cancer. / 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, Ling. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 217-253). / Abstracts also in Chinese. / ABSTRACT --- p.I / 摘要 --- p.IV / PUBLICATIONS --- p.VI / ACKNOWLEDGEMENTS --- p.X / TABLE OF CONTENTS --- p.XI / LIST OF FIGURES --- p.XIX / LIST OF TABLES --- p.XXIII / LIST OF ABBREVIATIONS --- p.XXV / Chapter CHAPTER 1 --- GENERAL INTRODUCTION / Chapter 1.1 --- Pancreas --- p.2 / Chapter 1.1.1 --- Gross anatomy --- p.2 / Chapter 1.1.2 --- Microscopic anatomy --- p.5 / Chapter 1.1.2.1 --- Acini cells --- p.7 / Chapter 1.1.2.2 --- Duct cells --- p.7 / Chapter 1.1.2.3 --- Stroma --- p.14 / Chapter 1.1.2.4 --- Islets cells --- p.15 / Chapter 1.1.3 --- Pancreatic diseases --- p.16 / Chapter 1.2 --- Pancreatic Cancer --- p.30 / Chapter 1.2.1 --- Epidemiology --- p.30 / Chapter 1.2.2 --- Risk factors --- p.32 / Chapter 1.2.3 --- Clinical symptoms, diagnosis and staging --- p.34 / Chapter 1.2.4 --- Types of pancreas tumor --- p.42 / Chapter 1.3 --- Treatment of Pancreatic Cancer --- p.47 / Chapter 1.3.1 --- Treatment for localized disease --- p.49 / Chapter 1.3.2 --- Treatment for locally advanced disease --- p.50 / Chapter 1.3.3 --- Treatment for metastatic disease --- p.52 / Chapter 1.4 --- Molecular Targets for Pancreatic Cancer Therapy --- p.56 / Chapter 1.4.1 --- Mechanisms of apoptosis --- p.56 / Chapter 1.4.2 --- Roles of mitochondrial pathway in apoptosis --- p.58 / Chapter 1.4.3 --- NF-κB activation on cancers --- p.59 / Chapter 1.4.4 --- CA19-9 as a therapeutic target for Pancreatic Cancer --- p.62 / Chapter 1.4.5 --- Ki-67 is associated with for cellular proliferation --- p.64 / Chapter 1.5 --- Applications of Chinese Medicine in Cancer Treatment --- p.66 / Chapter 1.5.1 --- Background of traditional Chinese medicine --- p.66 / Chapter 1.5.2 --- Chinese medicine herbs commonly used for cancer treatment --- p.67 / Chapter 1.6 --- Mouse Models of Pancreatic Cancer --- p.75 / Chapter 1.6.1 --- Anatomy of pancreas in mouse --- p.75 / Chapter 1.6.2 --- Pancreatic cancer models --- p.77 / Chapter 1.7 --- Hypothesis and Objectives of the Study --- p.83 / Chapter CHAPTER 2 --- ANTI-PANCREATIC CANCER EFFECTS OF TEN CHEMICAL COMPOUNDS DERIVED FROM FRUCTUS BRUCEAE ON CULTURED CAPAN-2 CELLS / Chapter 2.1 --- Introduction --- p.86 / Chapter 2.1.1 --- Brucea javanica L. Merr --- p.86 / Chapter 2.1.2 --- The fruit of Brucea javanica --- p.88 / Chapter 2.1.3 --- Used of Fructus Bruceae to treat cancers by Chinese medicine practitioners --- p.90 / Chapter 2.1.4 --- Biological activities of some chemical compounds from Brucea javanica --- p.90 / Chapter 2.1.5 --- Chemical structure of ten compounds isolated from Fructus Bruceae --- p.92 / Chapter 2.2 --- Materials and Methods --- p.96 / Chapter 2.2.1 --- Plant material --- p.96 / Chapter 2.2.2 --- Extratcion, fractionation, isolate and characterization --- p.96 / Chapter 2.2.3 --- General procedures on structural elucidation and phytochemical work --- p.100 / Chapter 2.2.4 --- Preparation of solutions of tern chemical compounds derived from Fructus Bruceae --- p.101 / Chapter 2.2.5 --- General cell culture methods --- p.101 / Chapter 2.2.6 --- Selection of appropriate seeding density of Capan-2 cells --- p.102 / Chapter 2.2.7 --- Cytotoxicity evaluation by SRB assay --- p.102 / Chapter 2.2.8 --- Statistical analyses --- p.103 / Chapter 2.3 --- Results --- p.105 / Chapter 2.3.1 --- Seletion of appropriate seeding density of Capan-2 cells --- p.105 / Chapter 2.3.2 --- IC₅₀ values of ten tested compounds and chemical structures --- p.107 / Chapter 2.4 --- Discussion --- p.111 / Chapter CHAPTER 3 --- INVOLVEMENT OF THE MITOCHONDRIAL PATHWAY IN BRUCEIN D-INDUCED APOPTOSIS IN CAPAN-2 CELLS / Chapter 3.1 --- Introduction --- p.116 / Chapter 3.2 --- Materials and Methods --- p.117 / Chapter 3.2.1 --- General cell culture --- p.117 / Chapter 3.2.2 --- Cytotoxicity assay --- p.119 / Chapter 3.2.3 --- Proliferation assay --- p.120 / Chapter 3.2.4 --- Hoechest fluorescence staining for morphological evaluation --- p.121 / Chapter 3.2.5 --- Cell cycle analysis by flow cytometry --- p.122 / Chapter 3.2.6 --- Quantitative analysis of apoptosis by Annexin V-PI staining assay --- p.122 / Chapter 3.2.7 --- Estimation of the changes of MMP on BD-treated Capan-2 cells --- p.123 / Chapter 3.2.8 --- Western blot analysis --- p.124 / Chapter 3.2.9 --- Statistical analyses --- p.125 / Chapter 3.3 --- Results --- p.126 / Chapter 3.3.1 --- BD significantly inhibited the proliferation of Capan-2 cells --- p.126 / Chapter 3.3.2 --- BD was less cytotoxic on cultured WRL68 and PPC cells than that of controls --- p.128 / Chapter 3.3.3 --- BD induced DNA condensation in Capan-2 cells --- p.131 / Chapter 3.3.4 --- BD induced an increase in the percentage of subG1 phase (apoptotic cells) --- p.133 / Chapter 3.3.5 --- BD dose-dependently induced cellular apoptosis to Capan-2 cells --- p.136 / Chapter 3.3.6 --- The MMP of Capan-2 cells were significantly attenuated by BD treatment --- p.139 / Chapter 3.3.7 --- BD increased the expression of apoptotic caspases in Capan-2 cells --- p.142 / Chapter 3.4 --- Discussion --- p.144 / Chapter CHAPTER 4 --- BRUCEIN D SUPPRESSES PANCREATIC TUMOR GROWTH IN AN ORTHOTOPIC MOUSE MODEL THROUGH THE CASPASE 3, 8, 9 AND NF-κB PATHWAYS / Chapter 4.1 --- Introduction --- p.150 / Chapter 4.2 --- Materials and Methods --- p.153 / Chapter 4.2.1 --- Ethics statement and animal holdings --- p.153 / Chapter 4.2.2 --- Cell culture --- p.153 / Chapter 4.2.3 --- Establishment of an orthotopic pancreatic cancer mouse model --- p.154 / Chapter 4.2.4 --- Treatment of orthotopic pancreatic cancer mice with BD --- p.155 / Chapter 4.2.5 --- Necropsy procedure and histological studies --- p.156 / Chapter 4.2.6 --- Hematoxylin-eosin staining --- p.156 / Chapter 4.2.7 --- Determination of CA19-9 and Ki-67 by immunofluorescence staining --- p.160 / Chapter 4.2.8 --- CA 19-9 expression in blood --- p.161 / Chapter 4.2.9 --- Western blot analysis of Caspase 3,8,9, IKKα and NF-κB p65 --- p.162 / Chapter 4.2.10 --- Extraction of the nucleus and cytoplasm from pancreatic tumor tissues --- p.163 / Chapter 4.2.11 --- Detection of the expression of NF-κB p65 in both cytoplasm and nuclear parts of pancreatic cancer cells --- p.165 / Chapter 4.2.12 --- Statistical analyses --- p.166 / Chapter 4.3 --- Results --- p.167 / Chapter 4.3.1 --- BD treatment enhanced the survival rate of tumor-bearing mice and significantly attenuated the tumor weight and volume --- p.167 / Chapter 4.3.2 --- Histological evaluation of the pancreas and pancreatic tumor after BD treatment --- p.175 / Chapter 4.3.3 --- BD significantly decreased the expression of CA19-9 in the blood samples of the experimental mice --- p.178 / Chapter 4.3.4 --- BD down regulated the expression of CA19-9 in pancreatic tumor tissues --- p.180 / Chapter 4.3.5 --- BD down regulated the expression of Ki-67 in pancreatic tumor tissues --- p.183 / Chapter 4.3.6 --- BD accentuated the expression of Caspase3, 8, 9 and decreased the expression of NF-κB p65 --- p.186 / Chapter 4.3.7 --- BD decreased the expression of NF-κB p65 in both cytoplasm and nucleus of pancreatic tumor cells --- p.189 / Chapter 4.4 --- Discussion --- p.191 / Chapter CHAPTER 5 --- GENERAL DISCUSSION, CONCLUSIONS AND FUTURE STUDIES / Chapter 5.1 --- General Discussion --- p.200 / Chapter 5.2 --- General Conclusions --- p.209 / Chapter 5.3 --- Limitation of Study --- p.211 / Chapter 5.4 --- Clinical Significance of Study Results --- p.212 / Chapter 5.5 --- Future Studies --- p.214 / Chapter 5.5.1 --- Investigation of the possible synergistic effect of combination of BD with gemcitabine on orthotopic pancreatic cancer mouse model --- p.214 / Chapter 5.5.2 --- Testing BD on different animal models --- p.215 / REFERENCES / References by Alphabetical Order --- p.217
346

Identification of molecular targets for Brucein D and metastasis suppressor genes in cancer through microRNA and RNAi screening.

January 2012 (has links)
微小RNA是内源性小非编码RNA,在肿瘤生成中扮演重要角色。Brucein D(BD)是一种B. javanica果实提取物,已被报道在胰腺癌中具有抗肿瘤作用。在此研究中,我们证明了BD在体内和体外均可抑制肝癌细胞生长。为了研究BD是否通过调节微小RNA来执行其抗肿瘤功能,我们进行了一个肿瘤微小RNA定量PCR阵列谱分析。此阵列包括95个已被报道与肿瘤有关的微小RNA。通过对比BD处理前后微小RNA谱的变化,我们发现微小RNA-95在BD处理后被显著下调了。其后促凋亡的CUGBP2被确定为微小RNA-95的下游靶基因。 / 胰腺癌是一种预后很差的恶性肿瘤,常常在确诊时已发生转移。为了找出在胰腺癌转移过程中发挥决定性作用的基因,我们进行了全基因组范围的RNA干扰筛选。一个包含针对全部人类基因的shRNA文库被导入胰腺癌细胞系capan-2.然后将这些细胞移植到裸鼠的胰腺中来建立一个原位胰腺癌小鼠模型。我们的假设是下调某个基因会促使低转移潜力的capan-2细胞转移到肝脏。通过从肝转移结节中回收shRNA模板,我们找到了几个推定的转移抑制基因。其中之一,SOX9,通过体内实验验证,证明下调SOX9基因的表达可促进胰腺癌转移。 / 化疗适用于进展期胰腺癌病人。然而他们对一线化疗药吉西他滨的反应并不乐观,这进一步使胰腺癌的预后变差。我们展开了一个全基因组范围的RNA干扰筛选来确定一些在化疗耐药过程中起关键作用的基因。携带上述shRNA文库的capan-2细胞被用于吉西他滨药物处理之下的筛选。通过微阵列分析,一些基因被筛选成为可影响癌细胞对药物敏感性的潜在的靶基因。通过进一步验证,LLGL1基因被确定为在调节癌细胞对化疗敏感性过程中起重要作用的基因。 / MicroRNAs (miRNAs) are endogenous small non-coding RNAs that have been shown to play important roles in tumorigenesis. Brucein D (BD), a chemical compound isolated from Brucea javanica fruit, has previously been reported to have anti-cancer effect in pancreatic cancer. In this study, we showed that BD also inhibited the growth of liver cancer cells both in vitro and in vivo. To investigate whether BD exerts its anti-cancer effect through regulation of miRNAs, we performed a cancer miRNA qPCR array profiling. From the profiling, miR-95 was found to be significantly down-regulated after BD treatment. Subsequently, a pro-apoptotic gene CUGBP2 was identified as a direct downstream target of miR-95. These findings suggested BD suppressed liver cancer cell growth through down-regulation of miR-95 and reinforcing CUGBP2. / Pancreatic cancer is an aggressive malignancy with extremely poor prognosis. It is usually diagnosed when metastases are already present. To identify genes that play critical roles in the processes of pancreatic cancer metastasis, a whole genome RNAi screening was performed. An shRNA library targeting all human genes was introduced into a human pancreatic cancer cell line capan-2. The infected cells were then transplanted into the pancreas of nude mice. Because capan-2 is of low metastatic potential, we hypothesized that knocking down of metastasis suppressor genes would facilitate capan-2 cells to spread to the liver. By retrieving shRNA templates from the liver metastatic nodules, several candidate genes were found. One of them, SOX9, has been validated as metastasis suppressor gene in vivo, implying that loss of expression of SOX9 promotes pancreatic cancer metastasis. / Chemotherapy is recommended for patients of pancreatic cancer in advanced stage. However, their response to the first-line chemotherapy drug gemcitabine is not satisfactory. A genome-wide RNAi screening was conducted to identify genes that were critical in chemotherapy resistance. Capan-2 cells containing the above shRNA library were applied for the screening under gemcitabine treatment. Through microarray analysis, a number of genes were screened as potential gemcitabine sensitivity genes. Validation experiments implied that the gene LLGL1 may play an important role in modulating pancreatic cancer cells’ sensitivity to gemcitabine. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Xia, Tian. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 125-134). / Abstracts also in Chinese. / Chapter Abstract --- p.I / Chapter Acknowledgements --- p.V / Chapter Abbreviations --- p.VI / Chapter List of Figures --- p.XV / Chapter List of Tables --- p.XVI / Chapter Part I: --- Brucein D-modulated microRNA-95 expression inhibits hepatocellular carcinoma cell growth --- p.1 / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Hepatocellular carcinoma --- p.1 / Chapter 1.1.1 --- Definition and classification --- p.1 / Chapter 1.1.2 --- Epidemiology --- p.1 / Chapter 1.1.3 --- Etiology --- p.3 / Chapter 1.1.4 --- Molecular pathogenesis of HCC --- p.4 / Chapter 1.1.4.1 --- Genomic instability --- p.4 / Chapter 1.1.4.2 --- Deregulation of key signaling pathways --- p.5 / Chapter 1.1.4.3 --- Epigenetic changes of HCC --- p.6 / Chapter 1.1.4.4 --- Two models of HCC pathogenesis --- p.7 / Chapter 1.1.5 --- Therapeutic methods and prognosis of HCC --- p.8 / Chapter 1.2 --- Apoptosis --- p.9 / Chapter 1.2.1 --- Types of cell death --- p.9 / Chapter 1.2.2 --- Apoptosis --- p.10 / Chapter 1.2.3 --- Morphological features of apoptosis --- p.10 / Chapter 1.2.4 --- Molecular mechanisms of apoptosis --- p.11 / Chapter 1.2.5 --- Apoptosis and cancer --- p.13 / Chapter 1.2.5.1 --- Imbalance of pro-apoptotic proteins and anti-apoptotic proteins --- p.13 / Chapter 1.2.5.2 --- Impaired caspases activity --- p.14 / Chapter 1.2.5.3 --- Deregulated death receptor signaling --- p.15 / Chapter 1.2.6 --- Cancer therapy targeting apoptotic defects --- p.15 / Chapter 1.3 --- microRNA --- p.16 / Chapter 1.3.1 --- Overview --- p.16 / Chapter 1.3.2 --- Biogenesis and maturation of microRNA --- p.17 / Chapter 1.3.3 --- Gene silencing by microRNA --- p.18 / Chapter 1.3.4 --- MicroRNA and cancers --- p.19 / Chapter 1.3.5 --- MicroRNA’s involvement in HCC --- p.21 / Chapter 1.3.6 --- Involvement of miR-95 in cancer --- p.22 / Chapter 1.4 --- Brucein D --- p.22 / Chapter 1.5 --- Aims of study --- p.23 / Chapter 2 --- Materials and Methods --- p.25 / Chapter 2.1 --- Cell Culture --- p.25 / Chapter 2.1.1 --- Mammalian Cell Culture --- p.25 / Chapter 2.1.2 --- Preparation of cell stock --- p.25 / Chapter 2.1.3 --- Cell recovery from liquid nitrogen stock --- p.26 / Chapter 2.1.4 --- Preparation of drugs for treatments --- p.26 / Chapter 2.1.5 --- Drug treatment --- p.26 / Chapter 2.1.6 --- Transfection of siRNA --- p.27 / Chapter 2.1.7 --- MTT Assay --- p.28 / Chapter 2.1.8 --- Luciferase reporter assays --- p.28 / Chapter 2.1.9 --- Annexin V Assay --- p.29 / Chapter 2.2 --- In vivo mouse model --- p.29 / Chapter 2.3 --- Tunel Assay (Terminal deoxynucleotide transferase dUTP Nick End Labeling Assay) --- p.30 / Chapter 2.4 --- RNA manipulation --- p.31 / Chapter 2.4.1 --- RNA Isolation --- p.31 / Chapter 2.4.2 --- Synthesis of cDNA from miRNA --- p.32 / Chapter 2.4.3 --- Synthesis of cDNA from RNA and quantitative PCR --- p.33 / Chapter 2.4.4 --- miRNA qPCR array --- p.34 / Chapter 2.5 --- DNA manipulation --- p.34 / Chapter 2.5.1 --- Agarose gel electrophoresis and purification of DNA --- p.34 / Chapter 2.5.2 --- Restriction enzymes digestion --- p.35 / Chapter 2.5.3 --- Ligation of DNA fragments --- p.36 / Chapter 2.5.4 --- Polymerase chain reaction --- p.36 / Chapter 2.5.5 --- Preparation of competent E. coli cells --- p.37 / Chapter 2.5.6 --- Transformation of E. coli cells --- p.37 / Chapter 2.5.7 --- Small scale plasmid isolation from E. coli (mini-prep) --- p.38 / Chapter 3 --- Results --- p.39 / Chapter 3.1 --- Brucein D inhibited the growth of HCC cells both in vitro and in vivo --- p.39 / Chapter 3.2 --- BD induced apoptosis in HCC cells --- p.43 / Chapter 3.3 --- miR-95 is an target of BD to modulate cell growth --- p.46 / Chapter 3.4 --- Identification of CUGBP2 as a downstream target of miR-95 --- p.55 / Chapter 4 --- Discussion --- p.60 / Chapter Part II: --- Genome-wide RNAi screening identifies tumor metastasis suppressor genes and drug sensitivity genes in pancreatic cancer --- p.65 / Chapter 1 --- Introduction --- p.65 / Chapter 1.1 --- Pancreatic cancer --- p.65 / Chapter 1.1.1 --- Overview --- p.65 / Chapter 1.1.2 --- Pancreatic ductal adenocarcinoma (PDAC) --- p.67 / Chapter 1.1.3 --- Molecular basis of PDAC --- p.67 / Chapter 1.1.3.1 --- KRAS --- p.67 / Chapter 1.1.3.2 --- TP53 --- p.68 / Chapter 1.1.3.3 --- CDKN2A --- p.69 / Chapter 1.1.4 --- Gemcitabine treatment in PDAC --- p.69 / Chapter 1.2 --- Metastasis --- p.71 / Chapter 1.2.1 --- Overview --- p.71 / Chapter 1.2.2 --- The stepwise process of metastasis --- p.72 / Chapter 1.2.3 --- Metastasis of pancreatic cancer --- p.74 / Chapter 1.3 --- SOX9 --- p.75 / Chapter 1.4 --- Aims of study --- p.77 / Chapter 2 --- Materials and Method --- p.78 / Chapter 2.1 --- Cell culture --- p.78 / Chapter 2.1.1 --- Mammalian Cell Culture --- p.78 / Chapter 2.1.2 --- MTT Assay --- p.78 / Chapter 2.1.3 --- Colony formation assay --- p.79 / Chapter 2.1.4 --- Wound healing assay --- p.79 / Chapter 2.1.5 --- Transwell migration chamber assay --- p.80 / Chapter 2.1.6 --- Immunocytochemistry --- p.80 / Chapter 2.1.7 --- Transient transfection of siRNA --- p.81 / Chapter 2.2 --- Establishment of in-vivo and in-vitro models --- p.82 / Chapter 2.2.1 --- shRNA library introduction --- p.82 / Chapter 2.2.2 --- Establishment of the orthotopic pancreatic cancer mouse model --- p.82 / Chapter 2.2.3 --- Package of lentivirus expressing shRNA --- p.83 / Chapter 2.2.4 --- Generation of stable cell line expressing shRNA --- p.84 / Chapter 2.3 --- DNA manipulation --- p.84 / Chapter 2.3.1 --- Large scale plasmid isolation from E. coli (maxi-prep) --- p.84 / Chapter 2.4 --- Analysis of Protein --- p.85 / Chapter 2.4.1 --- Preparation of protein cell lysates --- p.85 / Chapter 2.4.2 --- Protein concentration determination --- p.86 / Chapter 2.4.3 --- SDS-PAGE --- p.86 / Chapter 2.4.4 --- Immunoblotting (Western blotting) --- p.87 / Chapter 2.5 --- RNA manipulations --- p.88 / Chapter 2.5.1 --- RNA Isolation --- p.88 / Chapter 2.5.2 --- Synthesis of cDNA from RNA and quantitative PCR --- p.89 / Chapter 2.6 --- Analysis of Clinical Samples --- p.90 / Chapter 2.6.1 --- Clinical specimens --- p.90 / Chapter 2.6.2 --- Immunohistochemistry --- p.90 / Chapter 3 --- Results --- p.92 / Chapter 3.1 --- Genome-wide RNAi screening identifies genes as metastasis suppressors in an orthotopic pancreatic cancer mouse model --- p.92 / Chapter 3.2 --- SOX9 is a metastasis suppressor gene in pancreatic cancer --- p.97 / Chapter 3.3 --- Investigation into cellular functions of SOX9 --- p.102 / Chapter 3.3.1 --- SOX9’s effect on cell growth --- p.102 / Chapter 3.3.2 --- SOX9’s effect on cell migration --- p.105 / Chapter 3.4 --- Implication of SOX9 in human pancreatic cancer samples --- p.109 / Chapter 3.5 --- Genome-wide RNAi screening for the identification of gemcitabine sensitivity genes --- p.113 / Chapter 4 --- Discussion --- p.120 / Chapter General conclusions --- p.125
347

Effect of antisense oligonucleotide against glucose transporter on human hepatocellular carcinoma HepG2 and its multi-drug resistant R-HepG2 cells.

January 2001 (has links)
Lam Mei Wah. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 172-181). / Abstracts in English and Chinese. / Abstract --- p.i / 論文撮要 --- p.iv / Acknowledgement --- p.vii / Table of contents --- p.viii / List of tables --- p.xi / List of figures --- p.xii / Abbreviations --- p.xvii / Chapter Chapter 1: --- Introduction --- p.1 / Chapter 1.1 --- The facilitative glucose transporter family --- p.2 / Chapter 1.2 --- Overexpression of glucose transporters in tumor cells --- p.5 / Chapter 1.3 --- Antisense strategy --- p.8 / Chapter 1.3.1 --- Modifications of oligonucleotides --- p.9 / Chapter 1.3.2 --- Delivery system for oligonucleotides --- p.13 / Chapter 1.3.3 --- Factors influencing antisense activity --- p.16 / Chapter 1.3.4 --- Mechanism of action of antisense oligonucleotides --- p.17 / Chapter 1.3.5 --- Clinical trials of antisense treatment --- p.21 / Chapter 1.4 --- Objective of present study --- p.23 / Chapter Chapter 2: --- Materials and Methods --- p.24 / Chapter 2.1 --- Materials --- p.25 / Chapter 2.1.1 --- Reagents and buffers --- p.25 / Chapter 2.1.2 --- Reagents for Western blot analysis --- p.26 / Chapter 2.1.3 --- Culture medium --- p.28 / Chapter 2.1.4 --- Chemicals --- p.29 / Chapter 2.1.5 --- Culture of cells --- p.31 / Chapter 2.1.5.1 --- Differentiated Human Hepatoblastoma cell line (HepG2) --- p.31 / Chapter 2.1.5.2 --- "Multi-drug resistant hepatoma cell line, R-HepG2 cells" --- p.32 / Chapter 2.1.6 --- Animal Studies --- p.33 / Chapter 2.2 --- Methods --- p.34 / Chapter 2.2.1 --- In vitro studies --- p.34 / Chapter 2.2.1.1 --- Design of oligonucleotide sequence --- p.34 / Chapter 2.2.1.2 --- Transfection --- p.35 / Chapter 2.2.1.3 --- MTT assay --- p.36 / Chapter 2.2.1.4 --- Flow cytometry --- p.37 / Chapter 2.2.1.5 --- H-thymidine incorporation assay --- p.45 / Chapter 2.2.1.6 --- 2-Deoxy-D-[l-3H] glucose uptake assay --- p.46 / Chapter 2.2.1.7 --- Adenosine-5'-triphosphate (ATP) assay --- p.47 / Chapter 2.2.1.8 --- Western blot analysis --- p.50 / Chapter 2.2.2 --- In vivo studies --- p.55 / Chapter 2.2.2.1 --- Animal studies --- p.55 / Chapter (i) --- Lactate dehydrogenase (LDH) assay --- p.58 / Chapter (ii) --- Creatine kinase (CK) assay --- p.60 / Chapter (iii) --- Aspartate transaminase (AST) assay --- p.62 / Chapter (iv) --- Alanine transaminase (ALT) assay --- p.64 / Chapter Chapter 3: --- Results --- p.67 / Chapter 3.1 --- In vitro studies --- p.68 / Chapter 3.1.1 --- Characteristics of the multi-drug resistant cell line (R-HepG2) developed in our laboratory --- p.68 / Chapter 3.1.2 --- Effect of lipofectin on cell viability --- p.77 / Chapter 3.1.3 --- Cellular uptake of antisense oligonucleotide --- p.82 / Chapter 3.1.4 --- Effect of Glut 2 antisense oligonucleotides on human hepatoma HepG2 and its multidrug resistant (R-HepG2) cells by MTT assay --- p.87 / Chapter 3.1.5 --- Suppression of Glut 2 protein expression by antisense oligonucleotides as revealed by Western blot analysis --- p.96 / Chapter 3.1.6 --- Uptake of glucose in HepG2 and R-HepG2 after Glut 2 antisense treatment --- p.100 / Chapter 3.1.7 --- ATP content in HepG2 and R-HepG2 was lowered after treating the cells with antisense oligonucleotides --- p.108 / Chapter 3.1.8 --- Antisense oligonucleotides against Glut 2 exhibited antiproliferative effect on HepG2 and R-HepG2 cells --- p.117 / Chapter 3.1.9 --- Change in cell cycle pattern after antisense treatment --- p.125 / Chapter 3.1.10 --- Glut 2 antisense oligonucleotides did not induce apoptosis --- p.131 / Chapter 3.2 --- In vivo studies --- p.135 / Chapter 3.2.1 --- Effect of antisense oligonucleotides on the tumor weight in nude mice bearing HepG2 cells or R-HepG2 cells --- p.135 / Chapter 3.2.2 --- Assessment of any side effect of antisense drug done on normal tissues of nude mice --- p.139 / Chapter 3.2.2.1 --- Treatment on tumor bearing nude mice with Glut 2 antisense or sense oligonucleotides did not cause myocardial injury --- p.139 / Chapter 3.2.2.2 --- Liver injury was not detected in Glut 2 antisense or sense oligonucleotides treated tumor bearing nude mice --- p.147 / Chapter Chapter 4: --- Discussion --- p.151 / Chapter 4.1 --- In vitro study of the effect of antisense oligonucleotides against Glut 2 on HepG2 and its multi-drug resistant R-HepG2 cell lines --- p.152 / Chapter 4.1.1 --- Design of antisense oligonucleotides against Glut 2 --- p.154 / Chapter 4.1.2 --- Conditions for antisense inhibition by oligonucleotides --- p.155 / Chapter 4.1.3 --- Biological effects of antisense oligonucleotides --- p.158 / Chapter 4.2 --- In vivo study of the effect of antisense oligonucleotides against Glut 2 on HepG2 or R-HepG2 cells bearing nude mice --- p.166 / Chapter 4.2.1 --- Effect of Glut 2 antisense oligonucleotides on tumor weight --- p.167 / Chapter 4.2.2 --- In vivo side effects of oligonucleotides --- p.168 / Chapter 4.3 --- Conclusion --- p.169 / Bibliography --- p.172
348

Plants as bioreactors: expression of toxoplasma gondii surface antigen P30 in transgenic tobacco plants.

January 2001 (has links)
by Yu Wing Sze. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 119-126). / Abstracts in English and Chinese. / Thesis Committee --- p.ii / Statement --- p.iii / Acknowledgements --- p.iv / Abstract --- p.vi / 摘要 --- p.viii / Table of Contents --- p.x / List of Tables --- p.xvi / List of Figures --- p.xvii / List of Abbreviations --- p.xx / Chapter CHAPTER 1 --- General Introduction --- p.1 / Chapter CHAPTER 2 --- Literature Review --- p.3 / Chapter 2.1 --- Toxoplasma gondii --- p.3 / Chapter 2.1.1 --- Morphology and Life Cycle of T. gondii --- p.3 / Chapter 2.1.2 --- Routes of Transmission --- p.7 / Chapter 2.2 --- Toxoplasmosis --- p.8 / Chapter 2.2.1 --- Influences and Symptoms --- p.8 / Chapter 2.2.2 --- Treatment of Toxoplasmosis --- p.10 / Chapter 2.2.2.1 --- Antitoxoplasma Drugs --- p.10 / Chapter 2.2.2.2 --- Toxoplasma Vaccines --- p.12 / Chapter 2.3 --- Major T. gondii Surface Antigen - P30 --- p.16 / Chapter 2.4 --- Plants as Bioreactors --- p.19 / Chapter 2.4.1 --- Advantages of Plant Bioreactors --- p.19 / Chapter 2.4.2 --- Plant-based Vaccines --- p.20 / Chapter 2.4.2.1 --- VP2 Capsid Protein of Mink Enteritis Virus --- p.21 / Chapter 2.4.2.2 --- Hepatitis B Surface Antigen --- p.21 / Chapter 2.4.2.3 --- Norwalk Virus Capsid Protein --- p.22 / Chapter 2.5 --- Tobacco Expression System --- p.23 / Chapter 2.5.1 --- Transformation Methods --- p.23 / Chapter 2.5.1.1 --- Agrobacterium-mediated Transformation --- p.23 / Chapter 2.5.1.2 --- Direct DNA Uptake --- p.24 / Chapter 2.6 --- Phaseolin and Its Regulatory Sequences --- p.26 / Chapter CHAPTER 3 --- Expression of P30 in Transgenic Tobacco --- p.28 / Chapter 3.1 --- Introduction --- p.28 / Chapter 3.2 --- Materials and Methods --- p.29 / Chapter 3.2.1 --- Chemicals --- p.29 / Chapter 3.2.2 --- Oligos: Primers and Adapters --- p.29 / Chapter 3.2.3 --- Plant Materials --- p.31 / Chapter 3.2.4 --- Bacterial Strains --- p.31 / Chapter 3.2.5 --- Construction of Chimeric Genes --- p.31 / Chapter 3.2.5.1 --- Modification of pET-ASP30ΔPI --- p.32 / Chapter 3.2.5.2 --- Cloning of P30 into Vectors with Different Promoters --- p.38 / Chapter 3.2.5.2.1 --- Cloning ofP30 into Vector with CaMV 35S Promoter --- p.38 / Chapter 3.2.5.2.2 --- Cloning of P30 into Vector with Maize Ubiquitin 1 Promoter --- p.38 / Chapter 3.2.5.2.3 --- Cloning of P30 into Vector with Phaseolin Promoter --- p.38 / Chapter 3.2.5.2.4 --- Cloning of P30 into Vector with Phaseolin Promoter and Phaseolin SP --- p.39 / Chapter 3.2.5.3 --- Cloning of P30 into Agrobacterium Binary Vector pBI121 --- p.44 / Chapter 3.2.6 --- Transformation of Agrobacterium by Electroporation --- p.49 / Chapter 3.2.7 --- "Transformation, Selection and Regeneration of Tobacco " --- p.50 / Chapter 3.2.8 --- GUS Assay --- p.51 / Chapter 3.2.9 --- Synthesis of Single-stranded DIG-labeled DNA Probe --- p.51 / Chapter 3.2.10 --- Extraction of Genomic DNA from Leaves --- p.52 / Chapter 3.2.11 --- PCR of Genomic DNA with P30 Specific Primers --- p.53 / Chapter 3.2.12 --- Southern Blot Analysis of Genomic DNA --- p.53 / Chapter 3.2.13 --- Extraction of Total RNA from Leaves or Developing Seeds --- p.54 / Chapter 3.2.14 --- Reverse Transcription-Polymerase Chain Reaction of Total RNA --- p.55 / Chapter 3.2.15 --- Sequencing of RT-PCR Product --- p.56 / Chapter 3.2.16 --- Northern Blot Analysis of Total RNA --- p.56 / Chapter 3.2.17 --- Extraction of Total Protein from Leaves or Mature Seeds --- p.57 / Chapter 3.2.18 --- Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) --- p.58 / Chapter 3.2.19 --- Purification of 6xHis-tagged Proteins --- p.58 / Chapter 3.2.20 --- Western Blot Analysis of Total Protein --- p.59 / Chapter 3.2.21 --- In vitro Transcription and Translation --- p.60 / Chapter 3.2.21.1 --- Construction of Transcription Vector Containing Chimeric P30 Gene --- p.60 / Chapter 3.2.21.2 --- In vitro Transcription --- p.60 / Chapter 3.2.21.3 --- In vitro Translation --- p.60 / Chapter 3.3 --- Results --- p.65 / Chapter 3.3.1 --- Construction of Chimeric P30 Genes --- p.65 / Chapter 3.3.2 --- "Tobacco Transformation, Selection and Regeneration " --- p.65 / Chapter 3.3.3 --- Detection of GUS Activity --- p.67 / Chapter 3.3.4 --- Detection of P30 Gene in Transgenic Plants --- p.69 / Chapter 3.3.4.1 --- PCR of Genomic DNA --- p.69 / Chapter 3.3.4.2 --- Southern Blot Analysis --- p.72 / Chapter 3.3.5 --- Detection of P30 Transcript in Transgenic Plants --- p.75 / Chapter 3.3.5.1 --- RT-PCR --- p.75 / Chapter 3.3.5.2 --- Sequencing of RT-PCR Product --- p.79 / Chapter 3.3.5.3 --- Northern Blot Analysis --- p.79 / Chapter 3.3.6 --- Detection of P30 Protein in Transgenic Plants --- p.83 / Chapter 3.3.6.1 --- Western Blot Analysis of Total Protein and Ni-NTA Purified Proteins --- p.83 / Chapter 3.3.7 --- In vitro Transcription and Translation --- p.92 / Chapter 3.3.7.1 --- In vitro Transcription --- p.92 / Chapter 3.3.7.2 --- In vitro Translation --- p.92 / Chapter CHAPTER 4 --- Discussion --- p.97 / Chapter 4.1 --- General Conclusion --- p.97 / Chapter 4.2 --- Further Speculations and Investigations --- p.100 / Chapter 4.2.1 --- Other Protein Detection Procedures --- p.100 / Chapter 4.2.2 --- In vitro Transcription and Translation --- p.100 / Chapter 4.2.3 --- Gene Silencing at Transcription and/or Post-transcription Levels --- p.101 / Chapter 4.2.4 --- Gene Silencing at Translation and/or Post-translation Levels --- p.102 / Chapter (A) --- AUG Context Sequence --- p.102 / Chapter (B) --- Codon Usage --- p.103 / Chapter (C) --- N-end Rule --- p.107 / Chapter (D) --- Phaseolin Sorting Signal --- p.107 / Chapter CHAPTER 5 --- Future Perspectives --- p.109 / Chapter 5.1 --- Codon Modification of the P30 Gene --- p.110 / Chapter 5.2 --- Fusion of the P30 Gene with the LRP Gene --- p.117 / Chapter CHAPTER 6 --- Conclusion --- p.118 / References --- p.119
349

Hypolipidemic, antioxidative and vascular effects of soy leaves (Glycine max L. Merr.).

January 2001 (has links)
Ho Hing Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 140-156). / Abstracts in English and Chinese. / Chapter Chapter 1 --- General introduction / Chapter 1.1 --- History of soybean --- p.1 / Chapter 1.2 --- Health benefits of soybean --- p.2 / Chapter 1.3 --- Introduction to flavonoids --- p.2 / Chapter 1.4 --- Bioavailability of flavonoids from foods --- p.3 / Chapter 1.5 --- Pharmacological effects of flavonoids and their glycosides --- p.4 / Chapter 1.5.1 --- Anticarcinogenic activity --- p.4 / Chapter 1.5.2 --- Antioxidative activity --- p.7 / Chapter 1.5.3 --- Cardioprotective activity --- p.9 / Chapter 1.5.4 --- Osteoprotective activity --- p.10 / Chapter 1.5.5 --- Neuroprotective activity --- p.12 / Chapter 1.5.6 --- Antiangiogenic activity --- p.12 / Chapter 1.6 --- Soy leaves --- p.13 / Chapter Chapter 2 --- Isolation and purification of kaempferol glycosides and genistin in soy leaves / Chapter 2.1 --- Introduction --- p.14 / Chapter 2.2 --- Objectives --- p.15 / Chapter 2.3 --- Materials and Methods --- p.16 / Chapter 2.3.1 --- Extraction and isolation --- p.16 / Chapter 2.3.1.1 --- Preparation of soy leaves butanol extract --- p.16 / Chapter 2.3.1.2 --- Preparation of kaempferol glycosides from soy leaves butanol extract --- p.16 / Chapter 2.3.2 --- High performance liquid chromatography (HPLC) analysis --- p.19 / Chapter 2.3.2.1 --- Sample preparation for the HPLC analysis --- p.19 / Chapter 2.3.2.2 --- HPLC analysis --- p.19 / Chapter 2.3.2.3 --- Quantification of the flavonoids and their glycosides --- p.23 / Chapter 2.3.2.4 --- Change in flavonoids and their glycosides in soy leaves --- p.23 / Chapter 2.4 --- Results --- p.24 / Chapter 2.4.1 --- Compound 1 --- p.24 / Chapter 2.4.2 --- Compound 2 --- p.24 / Chapter 2.4.3 --- Compound 3 --- p.25 / Chapter 2.4.4 --- Compound 4 --- p.25 / Chapter 2.4.5 --- Compound 5 --- p.25 / Chapter 2.4.6 --- Compound 6 --- p.26 / Chapter 2.4.7 --- Quantification of flavonoids in soybean and soy leaves --- p.32 / Chapter 2.4.8 --- Age-dependent changes in flavonoids and their glycosides --- p.32 / Chapter 2.5 --- Discussion --- p.35 / Chapter 2.5.1 --- Compound 1 --- p.35 / Chapter 2.5.2 --- Compound 2 --- p.35 / Chapter 2.5.3 --- Compound 3 --- p.37 / Chapter 2.5.4 --- Compound 4 --- p.38 / Chapter 2.5.5 --- Compound 5 --- p.39 / Chapter 2.5.6 --- Compound 6 --- p.40 / Chapter 2.5.7 --- Age-dependent changes in flavonoids and their glycosides --- p.40 / Chapter Chapter 3 --- Hypolipidemic effects of soy leaves in hamsters / Chapter 3.1 --- Introduction --- p.41 / Chapter 3.1.1 --- Different lipoproteins and their functions --- p.41 / Chapter 3.1.2 --- Risk factors of cardiovascular disease --- p.42 / Chapter 3.1.3 --- Animal model --- p.43 / Chapter 3.2 --- Objectives --- p.44 / Chapter 3.3 --- Materials and Methods --- p.45 / Chapter 3.3.1 --- Animals --- p.46 / Chapter 3.3.2 --- Serum lipid and lipoprotein determinations --- p.46 / Chapter 3.3.3 --- Determination of cholesterol in the liver and adipose tissue --- p.46 / Chapter 3.3.4 --- Extraction of neutral and acidic sterols from fecal samples --- p.49 / Chapter 3.3.4.1 --- Determination of neutral sterols --- p.49 / Chapter 3.3.4.2 --- Determination of acidic sterols --- p.50 / Chapter 3.3.4.3 --- GLC analysis of neutral and acidic sterols --- p.51 / Chapter 3.3.5 --- Statistics --- p.51 / Chapter 3.4 --- Results --- p.54 / Chapter 3.4.1 --- Growth and food intake --- p.54 / Chapter 3.4.2 --- "Effects of SLP and SLEE supplementation on serum triacylglycerol (TG), total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C)" --- p.54 / Chapter 3.4.3 --- Effects ofSLP and SLEE supplementation on non-HDL-C and ratio of non-HDL-C to HDL-C --- p.55 / Chapter 3.4.4 --- Effects of SLP amd SLEE supplementations on concentration of hepatic cholesterol --- p.58 / Chapter 3.4.5 --- Effects of SLP and SLEE supplementations on perirenal adipose tissue cholesterol --- p.58 / Chapter 3.4.6 --- Effects of SLP and SLEE supplementations on fecal neutral and acidic sterols --- p.61 / Chapter 3.5 --- Discussion --- p.64 / Chapter Chapter 4 --- Effects of soy leaves and its flavonoid glycosides on haemolysis and on LDL oxidation / Chapter 4.1 --- Introduction --- p.67 / Chapter 4.1.1 --- Role of low density lipoprotein oxidation in the development of atherosclerosis --- p.68 / Chapter 4.1.2 --- LDL oxidation --- p.70 / Chapter 4.1.3 --- Thiobarbituric acid reactive substances (TBARS) as an index of LDL oxidation --- p.71 / Chapter 4.1.4 --- Antioxidant and LDL oxidation --- p.74 / Chapter 4.2 --- Objective --- p.75 / Chapter 4.3 --- Materials and methods --- p.76 / Chapter 4.3.1 --- Isolation of LDL from human serum --- p.76 / Chapter 4.3.2 --- LDL oxidation --- p.77 / Chapter 4.3.3 --- Determine the formation of thiobarbituric acid-reactive substances (TBARS) --- p.77 / Chapter 4.3.4 --- Assay for erythrocyte haemolysis --- p.78 / Chapter 4.3.5 --- Statistics --- p.79 / Chapter 4.4 --- Results --- p.80 / Chapter 4.4.1 --- Effects of three different soy leaves extracts and flavonoid glycosides on LDL oxidation --- p.80 / Chapter 4.4.2 --- Effects of three soy leaves extracts and flavonoid glycosides on erythrocyte haemolysis --- p.80 / Chapter 4.5 --- Discussion --- p.85 / Chapter Chapter 5 --- Relaxing effects of soy leaves and its flavonoids / Chapter 5.1 --- Introduction --- p.89 / Chapter 5.1.1 --- Smooth muscle contraction --- p.90 / Chapter 5.1.1.1 --- Sliding filament mechanism --- p.91 / Chapter 5.1.2 --- Intracellular mechanisms involved in the regulation of smooth muscle contraction --- p.92 / Chapter 5.1.2.1 --- Voltage-gated Ca2+ channels --- p.92 / Chapter 5.1.2.2 --- Protein kinase C (PKC) mediated smooth muscle contraction --- p.93 / Chapter 5.1.2.3 --- Thromboxane A2 receptor-mediated calcium channel --- p.94 / Chapter 5.2 --- Objectives --- p.96 / Chapter 5.3 --- Materials and methods --- p.97 / Chapter 5.3.1 --- Drugs preparation --- p.97 / Chapter 5.3.2 --- Vessel preparation --- p.97 / Chapter 5.3.3 --- Contraction experiments --- p.99 / Chapter 5.3.3.1 --- Relaxant responses of soy leaves butanol extract on the contraction induced by different constrictors --- p.99 / Chapter 5.3.3.2 --- Relaxant responses of soy leaves butanol extract on U46619 and PGF2a- induced contraction --- p.99 / Chapter 5.3.3.3 --- "Relaxant responses of genistein, genistin and the kaempferol glycosides on U46619-induced contraction" --- p.100 / Chapter 5.3.4 --- Statistics --- p.100 / Chapter 5.4 --- Results --- p.102 / Chapter 5.4.1 --- Effect of soy leaves butanol extract --- p.102 / Chapter 5.4.2 --- Role of endothelium in extract-induced relaxation --- p.102 / Chapter 5.4.3 --- Effect of the soy leaves butanol extract on contractile response to prostaglandins --- p.103 / Chapter 5.4.4 --- Effects of kaempferol glycosides and kaempferol --- p.111 / Chapter 5.4.5 --- Effects of genistein and genistin --- p.111 / Chapter 5.5 --- Discussion --- p.118 / Chapter Chapter 6 --- Effect of soy leaves on mammary tumor / Chapter 6.1 --- Introduction --- p.123 / Chapter 6.1.1 --- Carcinogenesis --- p.123 / Chapter 6.1.1.1 --- In itiation --- p.124 / Chapter 6.1.1.2 --- Promotion --- p.124 / Chapter 6.1.1.3 --- Progression --- p.125 / Chapter 6.2 --- Objective --- p.126 / Chapter 6.3 --- Materials and methods --- p.127 / Chapter 6.3.1 --- Animal --- p.127 / Chapter 6.3.2 --- Determination of estrus cycle --- p.128 / Chapter 6.3.3 --- Statistics --- p.129 / Chapter 6.4 --- Results --- p.131 / Chapter 6.4.1 --- Incident rate of tumor induction --- p.131 / Chapter 6.4.2 --- Number of tumor induced --- p.131 / Chapter 6.5 --- Discussion --- p.136 / Chapter Chapter 7 --- Conclusions --- p.136 / References --- p.140
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Avaliação de quimioterápicos, expressão gênica e quantificação de proteínas em carcinoma de cabeça e pescoço

Galbiatti-Dias, Ana Lívia Silva 02 October 2014 (has links)
Submitted by Fabíola Silva (fabiola.silva@famerp.br) on 2016-10-04T13:48:43Z No. of bitstreams: 1 analiviasilvagalbiatti_dissert.pdf: 5434854 bytes, checksum: b9182b3ea6a5987585226aa5a73bb3f1 (MD5) / Made available in DSpace on 2016-10-04T13:48:43Z (GMT). No. of bitstreams: 1 analiviasilvagalbiatti_dissert.pdf: 5434854 bytes, checksum: b9182b3ea6a5987585226aa5a73bb3f1 (MD5) Previous issue date: 2014-10-02 / Fundação de Amparo à Pesquisa do Estado de São Paulo - FAPESP / Introduction: Antifolate chemotherapies such as methotrexate (MTX) and 5-fluorouracil (5-FU) act inhibiting enzymes involved in folate pathway. These enzymes are important to DNA synthesis and cell growth. Chemotherapy dose may alter these levels of expression of these genes encoding enzymes involved in folate pathway and to influence in the response to treatment. Objectives: To evaluate relationship between mRNA and protein expression levels expression of MTHFR, DHFR, TYMS and SLC19A1 folate metabolic genes in laryngeal and oral cancer cell lines treated with MTX and 5-FU antifolate chemotherapies, separately. Materials and methods: HEP-2 (laryngeal cancer) and HN13 (oral cancer) cell lines were treated with 0.25, 25.0, and 75 μM of MTX and 10 ng/ml, 50 ng/ml, and 100 ng/ml of 5-FU, separately, for 24 hours/37°C. Flow Cytometry, Real-time PCR and Western blotting techniques were performed to analyzing the level of apoptosis, quantification of mRNA and quantification of proteins of genes, respectively. ANOVA and Bonferroni's post hoc tests were utilized for statistical analysis. P<0.05 was considered significant. Results: The higher concentration of MTX chemotherapeutic was associated with increased expression of MTHFR, DHFR, TYMS and SLC19A1 genes in laryngeal cancer cell line (p <0.05) and increased expression of DHFR and SLC19A1 genes in oral cancer cell line (p <0.05). The lower dose was associated with decreased expression of SLC19A1 gene laryngeal cancer (p <0.05). The higher concentration of 5-FU chemotherapy was associated with increased expression of DHFR gene in laryngeal cancer cell line (p <0.05) and increased expression of DHFR and TYMS genes in oral cancer cell line (p <0.05). The lower dose of 5-FU was associated with decreased expression of SLC19A1 gene. Conclusion: Exposure to low and high-dose of chemotherapeutics in oral cancer cell line can modulate the level of expression of genes involved in folate metabolism in laryngeal and oral cancer cell line. / Introdução: Quimioterápicos antifolato, tais como Methotrexato (MTX) e 5-Fluorouracil (5-FU) agem inibindo enzimas envolvidas na via do folato. Essas enzimas são essenciais para a síntese de DNA e divisão celular. A dose destes quimioterápicos podem alterar níveis de expressão de genes que codificam essas enzimas envolvidas na via do folato e influenciar na resposta ao tratamento. Objetivos: Avaliar a relação entre a expressão do RNAm e de proteínas dos genes MTHFR, DHFR, TYMS and SLC19A1 envolvidos no metabolismo do folato em linhagens celulares de câncer oral e câncer de laringe administradas com os quimioterápicos antifolato MTX e 5-FU em diferentes concentrações e em monoterapia. Materiais e métodos: Duas linhagens celulares HEP-2 (câncer da laringe) e HN13 (câncer de cavidade oral) foram tratadas com 0,25, 25,0 e 75 mM de MTX e 10 ng / ml, 50 ng / ml e 100 ng / ml de 5 -FU, separadamente, durante 24 horas a 37 °C. Técnicas de Citometria de Fluxo, PCR em tempo real e Western blotting foram realizadas para análise do nível de apoptose, quantificação do RNAm e quantificação das proteínas dos genes, respectivamente. Para análise estatística foi utilizado o teste ANOVA com correção de Bonferroni. P <0,05 foi considerado significante. Resultados: O aumento da concentração do quimioterápico MTX foi associado com expressão aumentada dos genes MTHFR, DHFR, TYMS e SLC19A1 na linhagem de câncer de laringe (p<0,05) e expressão aumentada dos genes DHFR e SLC19A1 na linhagem de câncer oral (p<0,05). A dose mais baixa de MTX foi associada com expressão diminuída do gene SLC19A1 em câncer de laringe (p<0,05). O aumento da concentração do quimioterápico 5-FU foi associado com expressão aumentada do gene DHFR na linhagem de câncer de laringe (p<0,05) e expressão aumentada dos genes TYMS e DHFR na linhagem de câncer oral (p<0,05). A dose mais baixa de 5-FU foi associada com expressão diminuída do gene SLC19A1. Conclusão: Exposição à alta ou baixa dose dos quimioterápicos MTX e 5-FU, em monoterapia, pode modular o nível de expressão de genes envolvidos no metabolismo do folato.

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