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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.
1

The role of physical activity in the prevention of breast and endometrial cancer /

Moradi, Tahereh, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 5 uppsatser.
2

Fermentation of dietary starch in man.

Ahmed, Rashid 06 March 2014 (has links)
Dietary starch that escapes digestion in the small intestine may be quantitatively more important than dietary fibre as substrate for fermentation. The products of fermentation have important implications in the pathogenesis of colorectal cancer and other diseases of the large bowel which are uncommon in Africans, but have a high prevalence in Western populations. Maize porridge is a staple of most Blacks in South Africa. Stale maize porridge (high resistant starch - HRS) seems to induce greater fermentation in the large bowel than fresh maize porridge (low resistant starch - LRS). In the present study, healthy colostomy subjects fed stale maize porridge had significantly more production of SCFA (short chain fatty acids) (mean SCFA - HRS = 182,6; mean SCFA - LRS = 116,1; p<0,05) in their colostomy effluent together with a significant drop in stool pH (mean pH - HRS = 5,91; mean pH - LRS = 6,70; p<0.G01). The SCFA butyrate tmean - HRS = 35,1; mean - LRS - LRS = 17,6; p<0,05) and acetate (mean - HRS = 93,9; mean - LRS = 65,8; p <0,05) were significantly elevated on the stale maize porridge diet when compared with consumption of fresh maize porridge. SCFA, propionate (mean - HRS = 43,1; mean - LRS = 24,8; p=G,Q5), also increased with stale maize porridge, but was not statistically significant. A high resistant starch diet and its resultant increase in fermentation products may be partly responsible in protecting the Black population against colorectal cancers and other large bowel diseases.
3

Routine biopsy of sonographically benign breast lesions greater than 3cm is necessary for the diagnosis of malignancy in women less than 40 years of age

Kemp, Marnie Laura January 2013 (has links)
A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Medicine in Diagnostic Radiology Johannesburg, 2013 / Palpable solid breast masses that are circumscribed and not calcified on mammogram or ultrasound are probably benign. There is controversy therefore, whether these deserve tissue diagnosis. More data is required to determine whether short term follow up can replace the need for biopsy. Benign appearing lesions greater than 3cm in diameter on ultrasound continue to undergo biopsy due to fear that a malignancy or phyllodes tumour might be missed. Published research reflects patients from Europe and North America, and no relevant data from Africa exists. AIM: This study aims to determine the histological spectrum of sonographically benign lesions greater than 3cm, which were biopsied, in our local population (majority of black patients) and to determine whether biopsy is indicated based on the local cancer risk. The study also aims to characterise the results by age and population group as well as correlate the histological result with the size of the lesion on ultrasound, the HIV status, family history and the seniority of the examining radiologists. MATERIALS AND METHODS: A retrospective descriptive study of biopsy results of sonographically benign breast masses was undertaken using biopsy procedural recording sheets. . The size of the lesions (continuous variables) mean with standard deviations was determined. The prevalence of lesions was expressed as a percentage. Other categorical variables were summarized as frequency and percentage. The vi histological spectrum of the lesions was determined. The HIV status and family history of the patients as well as the seniority of the reviewing radiologist was assessed. A Krusskal Wallis test and separate logistic regression analysis was used. RESULTS: A total of 68 patients (below 40 years of age) were included from a total of 13112 patients (of all ages) seen between 2007 and the end of 2010. 73 lesions were identified (65 benign and 8 malignant). The prevalence of benign lesions was 89.7%. .The prevalence of malignant lesions was 10.29%.There was little evidence to support lesion size for predicting histology (p value = 0.22) or benignity. There was little evidence that the family history and HIV status were significant. CONCLUSION: There was a high prevalence (10.29%) of malignancies in lesions classified by ultrasound as benign. The size of the lesion did not correlate with histological subtype or whether the lesion was benign or malignant. Training of sonographers, standardization of technique for established users and double reading, may produce a different result, as both junior and senior radiologists mistook malignant lesions for benign ones on ultrasound. Repeating this research using double reading after training may demonstrate whether there is a true higher prevalence of malignancy in ultrasonically benign breast lesions in our community. Until then, routine biopsy of these lesions is recommended.
4

Molecular mechanisms involved in induction of cell growth arrest and cell death in human colon cancer cells by tangutorine, a b-carboline.

January 2004 (has links)
Liu Bonnie Pui-ling. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 134-163). / Abstracts in English and Chinese. / Acknowledgments --- p.i / Abbreviations --- p.ii / Abstract / English --- p.1 / Chinese --- p.3 / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Colorectal Cancer Statistics --- p.5 / Chapter 1.2 --- Colon Cancer --- p.5 / Chapter 1.3 --- Treatment --- p.6 / Chapter 1.4 --- Effects of Cytotoxic Drug Treatment --- p.7 / Chapter 1.5 --- Cell Cycle --- p.8 / Chapter 1.6 --- Oxidases --- p.9 / Chapter 1.7 --- Chemistry of Novel β-carboline: Tangutorine --- p.11 / Chapter 1.8 --- Aim of Study --- p.14 / Chapter Chapter 2 --- Cytotoxicity / Chapter 2.1 --- Introduction --- p.15 / Chapter 2.2 --- Materials and Methods --- p.18 / Chapter 2.3 --- Results --- p.23 / Chapter 2.4 --- Discussion --- p.44 / Chapter Chapter 3 --- Oxidase Activity and Protein Oxidation / Chapter 3.1 --- Introduction --- p.48 / Chapter 3.2 --- Materials and Methods --- p.54 / Chapter 3.3 --- Results --- p.60 / Chapter 3.4 --- Discussion --- p.80 / Chapter Chapter 4 --- Cell Cycle / Chapter 4.1 --- Introduction --- p.89 / Chapter 4.2 --- Materials and Methods --- p.93 / Chapter 4.3 --- Results --- p.96 / Chapter 4.4 --- Discussion --- p.118 / Chapter Chapter 5 --- General Discussion --- p.126 / References --- p.134
5

Modeling cost-utility and cost-effectiveness analyses of Pap smear and visual inspection cervical cancer screening strategies in rural China. / 中國農村巴氏塗片和肉眼觀察宮頸癌篩查策略的成本效用及成本效果模型分析 / Zhongguo nong cun Bashi tu pian he ru yan guan cha gong jing ai shai cha ce lüe de cheng ben xiao yong ji cheng ben xiao guo mo xing fen xi

January 2013 (has links)
研究背景: / 2009年起,中國政府發起並資助了一項覆蓋全國31個省221個鄉村、針對100萬名農村婦女的細胞學及肉眼觀察宮頸癌篩查試點項目。國家及地方政府需要對可行的篩查策略進行衛生經濟學評估,為下一步擴大規模的篩查提供政策依據。 / 研究目標: / 應用人群特異性Markov模型,對巴氏塗片及肉眼觀察的宮頸癌篩查策略進行成本效果及成本效用兩方面的衛生經濟學評估,進而為中國農村婦女宮頸癌篩查政策的制定提供依據。 / 研究方法: / 本論文工作建立了Markov人群動態擬合模型,該模型能夠整合與中國農村宮頸癌流行情況相吻合的成本及健康狀況的數據,進而用於擬合20年內35-59歲中國農村婦女在有/無篩查幹預下的成本、效用和效果。本文分析的八個備選篩查策略包括:採用醋酸染色肉眼觀察(VIA)或傳統細胞學(巴氏塗片)分別進行10年,5年,3年及1年一次的篩查。 / 本文從社會學角度出發,成本數據涵蓋篩查、診斷及治療過程中產生的直接及間接成本。模型在結構上綜合了已被廣泛認可的宮頸癌自然發展史模型,以及宮頸癌及其癌前病變(CIN)在中國農村進行篩查和治療的標準臨床路徑。模型輸入參數盡可能地使用了能夠反映中國農村婦女人群特異性的數據。通過對比國家報告數據與模型預測結果,本文從全死因死亡率、宮頸癌死亡率及宮頸癌發病率三個方面驗證了模型的可信度。 / 模型的結局變量包括:累計成本、累計生命年(LYs)、累計質量調整生命年(QALYs)、預期宮頸癌死亡率及發病率降低百分比(%)、CIN 相對風險、宮頸浸潤癌相對風險,增量成本效用比(ICUR, 表述為每挽救一個質量調整生命年消耗的成本)及增量成本效果比(ICER, 表述為每挽救一個生命年消耗的成本)等。與無篩查幹預相比,我們界定ICUR及ICER小於三倍人均國內生產總值(76,824元,2009年)的優勢策略為‘具有成本效益’的選擇,並將其中ICUR和ICER最低的策略,定義為‘最具成本效益’的策略,將具有最大健康效益的策略(挽救最多質量調整生命年或生命年的策略),定義為‘最有效’的策略。同時,我們對可能影響決策的不確定因素進行了敏感性分析。 / 結果: / 與無篩查幹預相比,肉眼觀察及巴氏塗片篩查均能夠減少宮頸癌患病例數,進而顯示出一定的健康效益。較短的篩查間隔具有更高的健康效益。模型預測在不同的篩查策略幹預下,宮頸癌死亡率和發病率分別有望降低6.67-31.95%和5.12-24.71%,預期CIN發病相對風險為0.89-0.98,預期宮頸癌發病相對風險為0.73-0.95。篩查幹預對健康的保護作用在本研究中得到了證實。 / 成本效用分析顯示,10年一次的肉眼觀察策略最具成本效益,其次為5年一次、3年一次、1年一次的肉眼觀察篩查策略及1年一次的巴氏塗片篩查策略。與無篩查幹預相比,如上策略每挽救一個質量調整生命年消耗的成本為11,921至26,069元(1,892-4,138美元,2012年)。同時成本效果分析也顯示,10年一次的肉眼觀察策略最具成本效益,其次為5年一次的肉眼觀察策略及5年一次的巴氏塗片篩查策略。同樣與無篩查幹預相比,如上策略每挽救一個生命年消耗的成本為37,211至68,226元(5,906-18,830美元,2012年)。 / 對於某一既定策略,相應的ICUR和ICER受當地經濟狀況相關因素的影響最大,這些因素包括治療成本、篩查成本和成本貼現率。從檢測技術水平上看,肉眼觀察對分析結果的影響小於巴氏塗片,原因是前者敏感度範圍較小。篩查覆蓋率、初篩陽性隨訪率、診斷陽性治療率也都與相應的ICUR和ICER呈負相關性。敏感性分析結果顯示本文中模型對於健康結局的預測,及相關的衛生經濟學分析,受自然史模型中HPV感染和CIN之間轉移概率的不確定性的影響最大。HPV感染與CIN間的進展和逆轉概率是該項模型研究的核心參數。 / 結論: / 本文中成本效用和成本效果分析均顯示,相較於傳統的細胞學篩查策略,採用間隔時間較長(10年或5年)的肉眼觀察篩查策略,對一般發病地區的35-59歲的農村婦女來說,是更具‘成本效益’的選擇。對於宮頸癌高發地區,其篩查頻率可以提高到1年一次。1年一次的巴氏塗片篩查策略,是最有效的篩查策略,可以挽救最多的生命。但採用該策略時,應在財政預算允許的前提下,確保篩查技術和項目完成的質量。 / 篩查項目的高覆蓋率,對篩查陽性患者良好的隨訪和診治,初篩檢測技術平均水平以上的表現,以及較低的篩查和治療成本是確保篩查項目具備成本效益優勢的核心因素。本文完成的成本效用及成本效果分析,能夠為公共衛生決策提供重要的輔助作用。 / Background: / A Chinese government-sponsored cytology/visual inspection pilot cervical cancer screening program covered 10 million rural women in 221 counties of 31 provinces was initiated in 2009. Both the local and national governments in China need health economic evaluations of feasible strategies so as to make better policies for the next-step enlarging screening. / Objectives: / To perform health economic evaluations of Pap smear and visual inspection cervical cancer screening strategies using population-specific Markov modeling cost-utility (CUA) and cost-effectiveness (CEA) analyses, in order to assist screening policy making for women in rural China. / Methods: / Markov simulation models were developed to synthesize the evidence on costs and health outcomes related to cervical cancer epidemiology in rural China, and applied to predict the long-term utility, effectiveness and costs for hypothetical cohorts of 35-59 years old rural Chinese women, with or without the presence of screening over 20 years. The eight alternative screening strategies assessed were visual inspection with acetic acid (VIA) or traditional cytology (Pap smear) each with ten-year, five-year, three-year and one year screening intervals. / The study was conducted from the societal perspective, thus both directed and non-direct costs related to screening, diagnosis and treatment interventions were considered. The model structures incorporated with the well-accepted the natural history model of cervical cancer and the standard clinical pathway of screening and treatment interventions for precancerous lesions (CIN) and cervical cancer in real practice in rural China. Population-specific data were used as much as possible to be the model inputs. The model estimates were validated by comparison of our predictions of all-cause mortality, cervical cancer mortality and cervical cancer incidence with the national reported data. / Outcome variables included cumulative cost, life years (LYs), quality-adjusted life years (QALYs), predicted reduction(%) in cervical cancer mortality and incidence, relative risk of CIN, relative risk of cervical cancer, incremental cost-utility ratio (ICUR, presented as cost per QALY saved) and incremental cost-effectiveness ratio (ICER, presented as cost per life year saved). Compared with no screening, not-dominated strategies with ICUR and ICER less than three times China’s GDP per capita (76,824 CNY, 2009) were considered to be ‘cost-effective’ options. Among the identified ‘cost-effective’ options, the strategy with lowest ICUR or ICER was defined as the most cost-effective strategy, and the strategy with the highest health benefit (largest QALY saved or life year saved) was defined as the most effective strategy. Sensitivity analyses were conducted to test the effect of uncertainties on decision making. / Results: / All of the VIA and Pap smear screening strategies of showed certain benefits due to the decreased number of women developing cervical cancer, when compared with no screening. A trend for shorter screening interval to have greater benefit was also found. Cervical cancer mortality and incidence were expected to be reduced by 6.67-31.95% and 5.12-24.71% with different screening strategies. And the predicted relative risks of CIN and invasive cervical cancer of 0.89-0.98 and 0.73-0.95, respectively, also demonstrated the protective effect of screenings. / Modeling cost-utility analysis identified ten years VIA screening as the most cost-effective strategy followed by VIA screening with five-, three- and one year interval and Pap smear screening with a one year interval. Compared with no screening, the incremental costs per QALY saved of these strategies ranged from 11,921 to 26,069 Yuan (1,892-4,138 US dollars, 2012). In the meanwhile, modeling cost-effectiveness analysis also identified ten-years VIA screening as the most cost-effective strategy followed by VIA screening with five-year intervals and Pap smear screening with five-year intervals. Compared with no screening, the incremental costs per life year saved of these strategies ranged from 37,211 to 68,226 Yuan (5,906-18,830 US dollars, 2012). / Both ICUR and ICER of a selelected strategy were greatest influnced by factors related to variations in local economies , including treatment cost, screening cost and discounting rate of the cost. The influence of primary test performance of VIA was rather less than that of Pap smear due to the narrower ranges of the VIA sensitivities. Screening coverage, follow-up rate and treatment rate were also negatively associated with ICUR and ICER. Health outcome predictions and health economic analyses were mostly influenced by the uncertainties in HPV infection and CIN transitions in the natural history. Progression and regression probabilities between HPV infection and CIN were considered to be the key parameters of the simulation models. / Conclusions: / Baseline CUA and CEA results suggested that in comparison with traditional cytology screening strategies, organized VIA screening with long intervals (ten or five years) were more cost-effective options than for 35-59 years old women in normal incidence areas of rural China. The VIA screening interval can be shorten to one year in high incidence areas. Pap smear strategy with one year interval can be utilized as the most effective strategy with most lives saved when budget allows and the performances of program and test are ensured. / High coverage of the screening program, good management of screening positives, average or above performance of primary test, and lower screening and treatment costs are key elements for a cost-effective screening program. Cost-utility and cost-effectiveness analyses, such as the one conducted in this thesis study, can be considered important adjuncts to policy decision-making about public health objectives. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Li, Xue. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 388-401). / Abstracts also in Chinese; appendixes includes Chinese. / Abstract of thesis --- p.i / 中文摘要 --- p.v / ACKNOWLEDGEMENTS --- p.viii / TABLE OF CONTENTS --- p.1 / LIST OF TABLES --- p.8 / LIST OF FIGURES --- p.11 / ABBREVIATIONS --- p.12 / Chapter CHAPTER 1 --- INTRODUCTION --- p.14 / Chapter 1.1 --- Epidemiological patterns and disease burden of cervical cancer --- p.14 / Chapter 1.1.1 --- Cervical cancer incidence and mortality worldwide --- p.14 / Chapter 1.1.2 --- Risk factors for cervical cancer --- p.15 / Chapter 1.1.2.1 --- Human Papillomavirus (HPV) --- p.15 / Chapter 1.1.2.2 --- Parity --- p.16 / Chapter 1.1.2.3 --- Smoking --- p.16 / Chapter 1.1.2.4 --- Human Immunodeficiency Virus (HIV) --- p.17 / Chapter 1.1.2.5 --- Contraception --- p.17 / Chapter 1.1.2.6 --- Sexual behavior, nutrition and other factors --- p.18 / Chapter 1.1.3 --- Disease burden of cervical cancer in China --- p.18 / Chapter 1.1.3.1 --- Epidemiology of Cervical Cancer in China --- p.18 / Chapter 1.1.3.2 --- Cervical cancer in different geographic areas of China --- p.20 / Chapter 1.2 --- The need for cost-effectiveness analysis of cervical screening strategies in China --- p.21 / Chapter 1.2.1 --- Cervical cancer prevention in China --- p.21 / Chapter 1.2.2 --- Why do we need a modeling cost-effectiveness analysis? --- p.23 / Chapter 1.3 --- Natural history of cervical cancer --- p.25 / Chapter 1.3.1 --- Terminology --- p.25 / Chapter 1.3.2 --- Natural history of cervical cancer --- p.27 / Chapter 1.4 --- Secondary prevention strategies of cervical cancer --- p.29 / Chapter 1.4.1 --- Screening tests --- p.29 / Chapter 1.4.1.1 --- Cervical cytology --- p.29 / Chapter 1.4.1.2 --- Visual Inspection --- p.32 / Chapter 1.4.1.3 --- HPV testing --- p.36 / Chapter 1.4.2 --- Summary of different screening strategies all over the world --- p.37 / Chapter CHAPTER 2 --- LITERATURE REVIEW --- p.40 / Chapter 2.1 --- Background --- p.40 / Chapter 2.2 --- Objectives of the literature review --- p.41 / Chapter 2.3 --- Search strategies and results --- p.41 / Chapter 2.3.1 --- Search strategies --- p.41 / Chapter 2.3.2 --- Inclusion and exclusion criteria --- p.42 / Chapter 2.4 --- Literature results summary --- p.44 / Chapter 2.4.1 --- Methodology, target population and analytical perspective --- p.44 / Chapter 2.4.2 --- Screening test and program performance --- p.47 / Chapter 2.4.3 --- Cost and utility estimation --- p.49 / Chapter 2.4.4 --- Model parameter sources and validation --- p.53 / Chapter 2.4.5 --- Alternatives and identified cost-effective strategies --- p.58 / Chapter 2.5 --- Conclusions --- p.63 / Chapter CHAPTER 3 --- OBJECTIVES --- p.64 / Chapter 3.1 --- General Objectives --- p.64 / Chapter 3.2 --- Alternative cervical cancer screening strategies in this study --- p.64 / Chapter 3.3 --- Decision rules for recommended cost-effective options --- p.65 / Chapter 3.4 --- Analytical perspective and time horizon --- p.65 / Chapter 3.5 --- Objectives --- p.66 / Chapter 3.6 --- Analytical scenario in this study --- p.66 / Chapter 3.6.1 --- Patterns of cervical screening program delivery in rural China --- p.67 / Chapter 3.6.2 --- Demographic profile of the simulated hypothetical cohort --- p.67 / Chapter 3.6.3 --- Summary of model assumptions --- p.68 / Chapter 3.6.3.1 --- Assumptions related to screening performance and clinical practice --- p.68 / Chapter 3.6.3.2 --- Assumptions related to epidemiological characteristics of cervical cancer --- p.68 / Chapter 3.6.3.3 --- Assumptions related to economic evaluation --- p.69 / Chapter CHAPTER 4 --- METHODOLOGY --- p.70 / Chapter 4.1 --- Alternative strategies in this study --- p.70 / Chapter 4.2 --- Markov Model Developments and Applications --- p.72 / Chapter 4.2.1 --- General introduction of Markov Transition Model --- p.72 / Chapter 4.2.2 --- Structure of Markov models --- p.76 / Chapter 4.2.2.1 --- Natural history model of cervical cancer --- p.76 / Chapter 4.2.2.2 --- Structure of Pap smear and Visual Inspection screening models --- p.82 / Chapter 4.2.2.3 --- Structure of precancerous lesion and invasive cancer treatment models --- p.83 / Chapter 4.2.2.4 --- Interaction of the models --- p.85 / Chapter 4.2.3 --- Demographic profile of the hypothetical cohort --- p.86 / Chapter 4.2.4 --- Probabilities --- p.88 / Chapter 4.2.4.1 --- Identification and converting between rate and probability --- p.89 / Chapter 4.2.4.2 --- Initial probabilities --- p.90 / Chapter 4.2.4.3 --- Transition probabilities --- p.91 / Chapter 4.2.5 --- Screening, diagnosis and treatment characteristics --- p.101 / Chapter 4.2.5.1 --- Screening program characteristics --- p.101 / Chapter 4.2.5.2 --- Diagnosis test performance --- p.104 / Chapter 4.2.5.3 --- Precancerous lesions treatment characteristics --- p.104 / Chapter 4.2.5.4 --- Invasive cancer and treatment characteristics --- p.106 / Chapter 4.2.6 --- Model validation --- p.111 / Chapter 4.3 --- Cost data collection --- p.112 / Chapter 4.3.1 --- Perspective of study --- p.112 / Chapter 4.3.2 --- Selection of study sites --- p.113 / Chapter 4.3.3 --- Screening cost data collection --- p.113 / Chapter 4.3.4 --- Treatment cost data collection --- p.115 / Chapter 4.4 --- Cost-utility analysis and cost-effectiveness analysis --- p.117 / Chapter 4.4.1 --- General introduction of these two analyses --- p.117 / Chapter 4.4.2 --- Utility Estimates --- p.118 / Chapter 4.4.3 --- Screening utility and effectiveness evaluation --- p.120 / Chapter 4.4.4 --- Cost-effectiveness and cost-utility analysis method --- p.122 / Chapter 4.5 --- Time horizon and discounting rate --- p.125 / Chapter 4.6 --- Summary of modeling assumptions --- p.126 / Chapter 4.6.1 --- Assumptions related to screening performance and clinical practice --- p.126 / Chapter 4.6.2 --- Assumptions related to epidemiological characteristics of cervical cancer --- p.127 / Chapter 4.6.3 --- Assumptions related to economic evaluation --- p.128 / Chapter 4.7 --- Sensitivity analysis --- p.128 / Chapter 4.8 --- Ethical approval --- p.129 / Chapter CHAPTER 5 --- RESULTS --- p.130 / Chapter 5.1 --- Model validation --- p.130 / Chapter 5.2 --- Cost analysis results --- p.134 / Chapter 5.2.1 --- Screening costs results --- p.134 / Chapter 5.2.2 --- Treatment cost results --- p.136 / Chapter 5.2.3 --- The proportional costs breakdown for different screening strategies --- p.139 / Chapter 5.3 --- Utility estimation results --- p.141 / Chapter 5.4 --- Cost-utility analysis results --- p.144 / Chapter 5.4.1 --- Baseline analysis --- p.144 / Chapter 5.4.2 --- Influence of screening program performance --- p.148 / Chapter 5.4.2.1 --- Coverage of the screening program --- p.148 / Chapter 5.4.2.2 --- Follow up rate and treatment rate of positives --- p.155 / Chapter 5.4.3 --- Influence of screening test performance --- p.159 / Chapter 5.4.4 --- Influence of costs --- p.165 / Chapter 5.4.4.1 --- Influence of screening costs --- p.165 / Chapter 5.4.4.2 --- Influence of treatment costs --- p.168 / Chapter 5.4.5 --- Influence of discounting --- p.171 / Chapter 5.4.6 --- Summary of factors and their influences on the baseline CUA results --- p.174 / Chapter 5.5 --- Cost-Effectiveness analysis results --- p.180 / Chapter 5.5.1 --- Baseline analysis --- p.180 / Chapter 5.5.1.1 --- Life year saved --- p.181 / Chapter 5.5.1.2 --- Cervical cancer mortality reduction --- p.185 / Chapter 5.5.1.3 --- Cervical cancer incidence reduction --- p.187 / Chapter 5.5.1.4 --- Relative risk of CIN and cervical cancer --- p.189 / Chapter 5.5.1.5 --- Effectiveness summary of alternative screening strategies on the hypothetical 100,000 rural Chinese women --- p.191 / Chapter 5.5.2 --- Factors that influence the CEA results --- p.195 / Chapter 5.5.2.1 --- Best scenario analysis --- p.196 / Chapter 5.5.2.2 --- Worst scenario analysis --- p.201 / Chapter 5.5.2.3 --- Summary of the possible ranges of costs and effectiveness in different scenarios --- p.206 / Chapter 5.6 --- Sensitivity analysis --- p.209 / Chapter 5.6.1 --- Sensitivity analysis of Cost-Utility analysis results --- p.209 / Chapter 5.6.1.1 --- Tornado analysis --- p.209 / Chapter 5.6.1.2 --- One-way sensitivity analysis --- p.213 / Chapter 5.6.2 --- Sensitivity analysis of Cost-Effectiveness analysis results --- p.220 / Chapter 5.6.2.1 --- Tornado analysis --- p.220 / Chapter 5.6.2.2 --- One-way sensitivity --- p.224 / Chapter 5.6.3 --- Summary of sensitivity results --- p.236 / Chapter CHAPTER 6 --- SUMMARY, DISSICUSSION AND CONCLUSIONS --- p.240 / Chapter 6.1 --- Summary of Markov model development and validation --- p.240 / Chapter 6.1.1 --- Category and source summary of input parameters --- p.240 / Chapter 6.1.2 --- Model validation --- p.244 / Chapter 6.2 --- Summary of modeling results --- p.245 / Chapter 6.2.1 --- Summary of Cost-Utility Analysis --- p.245 / Chapter 6.2.1.2 --- Baseline analysis findings --- p.245 / Chapter 6.2.1.2 --- Influential factors on the cost-effective manner of alternative strategies --- p.246 / Chapter 6.2.2 --- Summary of Cost-Effectiveness Analysis --- p.250 / Chapter 6.2.2.1 --- Baseline analysis findings --- p.251 / Chapter 6.2.2.2 --- Possible ranges for cost and effectiveness of alternative strategies under different scenarios --- p.253 / Chapter 6.2.3 --- Summary of CUA and CEA findings --- p.257 / Chapter 6.2.4 --- Summary of sensitivity analysis --- p.259 / Chapter 6.2.4.1 --- Important variables on health outcome predictions --- p.259 / Chapter 6.2.4.2 --- Sensitive variables to the baseline CUA and CEA recommendations --- p.260 / Chapter 6.2.4.3 --- Overview of the sensitivity analysis --- p.263 / Chapter 6.3 --- Discussion --- p.264 / Chapter 6.3.1 --- Alternative strategies of cervical cancer screening in rural China --- p.264 / Chapter 6.3.1.1 --- Target ages --- p.265 / Chapter 6.3.1.2 --- Screening intervals --- p.266 / Chapter 6.3.1.3 --- Feasible primary screening tests --- p.267 / Chapter 6.3.1.4 --- Service delivering patterns --- p.269 / Chapter 6.3.1.5 --- Time horizon of this thesis study --- p.270 / Chapter 6.3.2 --- Transition probability estimation --- p.271 / Chapter 6.3.3 --- Screening and treatment cost estimation --- p.276 / Chapter 6.3.3.1 --- Representativeness of the selected counties --- p.276 / Chapter 6.3.3.2 --- Screening costs of VIA and Pap smear --- p.277 / Chapter 6.3.3.3 --- Treatment costs --- p.279 / Chapter 6.3.4 --- Utility estimation --- p.280 / Chapter 6.3.4.1 --- Instrument selection --- p.280 / Chapter 6.3.4.2 --- Utility estimation between studies --- p.281 / Chapter 6.3.5 --- Baseline cost-utility and cost-effectiveness analyses --- p.283 / Chapter 6.3.6 --- Sensitivity Analysis --- p.284 / Chapter 6.3.7 --- Strengths and limitations --- p.286 / Chapter 6.3.7.1 --- Limitations --- p.286 / Chapter 6.3.7.2 --- Strengths --- p.288 / Chapter 6.4 --- Policy implications --- p.289 / Chapter 6.4.1 --- How to manage a cost-effective cervical cancer screening program? --- p.289 / Chapter 6.4.2 --- How can VIA screening be adopted? --- p.290 / Chapter 6.4.3 --- How can Pap smear screening be adopted? --- p.291 / Chapter 6.4.4 --- Framework for policy decision making --- p.292 / Chapter 6.5 --- Conclusions --- p.295 / Chapter APPENDIX --- p.300 / Chapter Appendix 1-1 --- The 2001 Bethesda System* --- p.300 / Chapter Appendix 1-2 --- The FIGO Staging for cervical cancers* --- p.301 / Chapter Appendix 1-3 --- Cervical Cancer Screening Program in different countries --- p.302 / Chapter Appendix 4-1 --- WHO World Standardized Population Distribution (%) --- p.305 / Chapter Appendix 4-2 --- Summary of transition probabilities literature review --- p.306 / Chapter Appendix 4-3 --- Price Indices from 1978 to 2010 --- p.326 / Chapter Appendix 4-4 --- Screening Cost Questionnaire --- p.327 / Chapter Appendix 4-5 --- Programmatic Cost Survey Questionnaire --- p.339 / Chapter Appendix 4-6 --- Treatment Cost Survey Questionnaire --- p.342 / Chapter Appendix 4-7 --- EQ-5D Algorism (UK) --- p.344 / Chapter Appendix 4-8 --- Chinese Version of EQ5D----HQOL score questionnaire --- p.345 / Chapter Appendix 5-1 --- Calibrated variables and its final settings --- p.348 / Chapter Appendix 5-2 --- Cervical cancer new cases and deaths all over the world in 2008 --- p.349 / Chapter Appendix 5-3 --- Data distribution of CIN2-3 and cervical cancer treatment costs --- p.350 / Chapter Appendix 5-4 --- Relative risk of CIN and cervical cancer by age groups of alternative screening strategies --- p.361 / Chapter Appendix 5-5 --- Influence of discounting rate of life years on the CEA results --- p.363 / Chapter Appendix 5-6 --- Tornado analysis results based on the effect on QALYs predictions --- p.367 / Chapter Appendix 5-7 --- Tornado analysis results based on the effect on life-year predictions --- p.372 / Chapter Appendix 6-1 --- Summary of Markov Model Inputs and Sources --- p.377 / REFERENCE --- p.388
6

Mechanisms underlying chemopreventive effect of celecoxib in gastric carcinogenesis.

January 2006 (has links)
Chu Wai Kit. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 87-96). / Abstracts in English and Chinese. / Acknowledgments --- p.ii / Publication --- p.iii / List of Abbreviations --- p.iv / List of Tables --- p.v / List of Figures --- p.vi / Abstract --- p.vii / 摘要 --- p.x / Table of Contents --- p.xii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Epidemiology of gastric cancer --- p.1 / Chapter 1.2 --- Risk factors associated with gastric cancer --- p.7 / Chapter 1.3 --- Prevention of Gastric Cancer --- p.9 / Chapter 1.4 --- H. pylori eradication and gastric cancer development --- p.11 / Chapter 1.5 --- Non-steroidal anti-inflammatory drugs and gastric cancer prevention --- p.13 / Chapter 1.6 --- COX-2 independent pathway --- p.14 / Chapter 1.7 --- Animal model of gastric cancer --- p.15 / Chapter 1.8 --- Microarray system --- p.16 / Chapter 1.9 --- Hypothesis --- p.18 / Chapter 1.10 --- Aim of study --- p.19 / Chapter Chapter 2 --- Chemoprevention of gastric cancer by celecoxib --- p.20 / Chapter 2.1 --- Introduction --- p.20 / Chapter 2.2 --- Material and Methods --- p.22 / Chapter 2.2.1 --- Animals --- p.22 / Chapter 2.2.2 --- Chemicals --- p.22 / Chapter 2.2.3 --- Study design --- p.23 / Chapter 2.2.4 --- Cell Culture --- p.24 / Chapter 2.2.5 --- Celecoxib treatment --- p.24 / Chapter 2.2.6 --- Cell proliferation assay --- p.25 / Chapter 2.3 --- Results --- p.26 / Chapter 2.3.1 --- Chemoprevention of gastric cancer by celecoxib in rats --- p.26 / Chapter 2.3.2 --- Effects of celecoxib on growth of human gastric cancer cells --- p.29 / Chapter 2.4 --- Discussion --- p.30 / Chapter 2.4.1 --- MNNG induced gastric cancer effectively --- p.30 / Chapter 2.4.2 --- Celecoxib significantly suppressed gastric carcinogenesis in rats --- p.31 / Chapter 2.4.3 --- Celecoxib inhibited the growth of MKN 45 in a concentration-dependent manner --- p.31 / Chapter 2.4.4 --- Celecoxib may exert its anti-tumor property through COX independent pathway --- p.32 / Chapter Chapter 3 --- Gene expression profiles of celecoxib treated rat gastric tumor and human gastric cells --- p.34 / Chapter 3.1 --- Introduction --- p.34 / Chapter 3.2 --- Material and Methods --- p.34 / Chapter 3.2.1 --- RNA extraction --- p.34 / Chapter 3.2.2 --- Target preparation and Array hybridization --- p.35 / Chapter 3.2.3 --- Post-hybridization processing and Scanning --- p.36 / Chapter 3.2.4 --- Microarray data analysis --- p.36 / Chapter 3.2.5 --- Quantitative RT-PCR --- p.37 / Chapter 3.3 --- Results --- p.39 / Chapter 3.3.1 --- Gene expression profiles of rat gastric tumors --- p.39 / Chapter 3.3.1.1 --- Genes differentially expressed in MNNG induced gastric tumors --- p.39 / Chapter 3.3.1.2 --- Genes differentially expressed in celecoxib treated group --- p.42 / Chapter 3.3.1.3 --- Mechanisms underlying chemoprevention of celecoxib --- p.43 / Chapter 3.3.2 --- Verification of gene expression by quantitative RT-PCR --- p.55 / Chapter 3.3.3 --- Confirmation of the gene expression profiles in human by quantitative RT-PCR --- p.59 / Chapter 3.4 --- Discussions --- p.63 / Chapter Chapter 4 --- Effects of celecoxib on Akt pathway in gastric cancer cells --- p.68 / Chapter 4.1 --- Introduction --- p.68 / Chapter 4.2 --- Material and methods --- p.72 / Chapter 4.2.1 --- Protein extraction --- p.72 / Chapter 4.2.2 --- Western blotting --- p.72 / Chapter 4.3 --- Results --- p.74 / Chapter 4.3.1 --- Expression of the Akt pathway after treatment with celecoxib --- p.74 / Chapter 4.4 --- Discussions --- p.78 / Chapter Chapter 5 --- Conclusion --- p.82 / References --- p.87
7

Modulation of cytochrome P4501A1/1B1 and UDP-glucuronosyltransferase activities by hydroxychalcones and monoterpenes.

January 2003 (has links)
Wang Huan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 148-158). / Abstracts in English and Chinese. / TABLE OF CONTENTS --- p.I / LIST OF FIGURES AND TABLES --- p.VIII / ABSTRACT --- p.1 / 摘要 --- p.3 / Chapter CHAPTER 1 --- GENERAL INTRODUCTION / Chapter I. --- The essential factors related to cancer --- p.5 / Chapter a. --- Carcinogens --- p.5 / Chapter b. --- Carcinogenesis pathways --- p.7 / Chapter c. --- DNA adducts formation and breast cancer --- p.7 / Chapter II. --- Cytochrome P450 I enzyme family --- p.8 / Chapter a. --- CYP450 superfamily --- p.8 / Chapter b. --- CYP1A1 --- p.10 / Chapter c. --- CYP1B1 --- p.11 / Chapter III. --- Transactivation of CYP1 enzymes by aryl hydrocarbon receptor (AhR) --- p.12 / Chapter IV. --- Phase II enzyme UGT and cancer prevention --- p.13 / Chapter V. --- Estrogen metabolism and the hormone-dependent breast cancer --- p.15 / Chapter a. --- Estrogen and breast cancer initiation --- p.15 / Chapter b. --- Estrogen Receptor (ER) --- p.15 / Chapter c. --- Estradiol hydroxylation pathways --- p.15 / Chapter VI. --- Phytochemicals and cancer prevention --- p.18 / Chapter VII. --- Outline of this study --- p.20 / Chapter CHAPTER 2 --- MATERIALS AND METHODS / Chapter I. --- Chemicals --- p.21 / Chapter II. --- Cell culture and treatments --- p.21 / Chapter 1. --- Maintenance of cells --- p.21 / Chapter 2. --- Preparation of cell stock --- p.22 / Chapter 3. --- Cell recovery from liquid nitrogen stock --- p.22 / Chapter 4. --- Measurement of cell viability --- p.22 / Chapter 5. --- Preparation of cell lysates --- p.23 / Chapter 6. --- XRE-luciferase gene reporter assay --- p.23 / Chapter a. --- Transient transfection of cell using lipofectamine PLUS reagent --- p.23 / Chapter b. --- Dual Luciferase Assay --- p.24 / Chapter III. --- Enzyme Activities --- p.24 / Chapter 1. --- Isolation of microsomes --- p.24 / Chapter 2. --- EROD activities in intact cells --- p.24 / Chapter 3. --- EROD inhibition assay --- p.25 / Chapter IV. --- Manipulation of Nuclear Acid --- p.26 / Chapter 1. --- Preparation of transfected DNA --- p.26 / Chapter a. --- Separation and purification of DNA from agarose gel --- p.26 / Chapter b. --- Restriction digestion --- p.26 / Chapter c. --- Ligation of DNA fragments --- p.27 / Chapter d. --- Transformation of DH5a --- p.27 / Chapter e. --- Small scale plasmid purification from DH5a (mini prep) --- p.28 / Chapter f. --- Large scale plasmid isolation from DH5a (maxi-prep) --- p.28 / Chapter g. --- Construction of XRE activated luciferase reporter gene --- p.29 / Chapter 2. --- Measurement of DMBA-DNA adduct formation --- p.29 / Chapter 3. --- Semi-quantitative RT-PCR Assay --- p.30 / Chapter a. --- Isolation of RNA using TRIzol® Reagent --- p.30 / Chapter b. --- RT-PCR --- p.31 / Chapter V. --- Phase II enzyme-UGT activity assay --- p.32 / Chapter VI. --- HPLC for estradiol-hydroxylation analysis --- p.33 / Chapter 1. --- HPLC condition for hydroxyestradiol separation and measurement --- p.33 / Chapter 2. --- Determination of microsomal estradiol hydroxylase activity --- p.34 / Chapter 3. --- Assay of estradiol metabolism in MCF-7 cells --- p.34 / Chapter VII. --- Statistical Analysis --- p.35 / Chapter CHAPTER 3 --- CHALCONES ANTAGONIZE DMBA-INDUCED CARCINOGENESIS BY MODULATION OF CYP1A1/1B1 AND UGT ACTIVITIES / Chapter Part One --- Introduction --- p.36 / Chapter Part Two --- Results --- p.40 / Chapter Section One --- Chalcones antagonize DMBA carcinogenesis by inhibiting CYP1A1 and CYP1B1 activities --- p.40 / Chapter I. --- Chalcones inhibited DMBA-induced EROD activities in MCF-7 cells --- p.40 / Chapter II. --- Inhibition of chalcones on microsomal CYP1A1 & 1B1 enzyme activities --- p.43 / Chapter III. --- Reduction of DMBA-induced DNA adduct by chalcones --- p.52 / Chapter IV. --- Chalcones antagonized CYP1A1 XRE transactivation --- p.54 / Chapter V. --- Chalcones suppressed DMBA-induced CYP1 gene expression --- p.56 / Chapter Section Two --- Chalcones modulate DMBA carcinogenesis by regulating UGT activities --- p.63 / Chapter I . --- Chalcones regulated UGT1A1 gene expression in MCF-7 cells --- p.63 / Chapter II. --- Chalcones affected UGT enzyme activity in HepG2 cells --- p.70 / Chapter III. --- Chalcones regulated UGT1A1 gene expression in HepG2 cells --- p.73 / Chapter Part Three --- Discussion --- p.80 / Chapter I . --- Chalcones are potential chemopreventive agents --- p.80 / Chapter II. --- Chalcones modulated Phase I enzyme activities --- p.80 / Chapter III. --- Chalcones regulated Phase II enzyme activities --- p.82 / Chapter IV. --- Chalcones suppressed DMBA-induced DNA-adduct formation in MCF-7 cells --- p.82 / Chapter V. --- The anti-carcinogenic properties of chalcones and their structures --- p.83 / Chapter CHAPTER 4 --- EFFECTS OF PERILLYL ALCOHOL AND LIMONENE ON CYP1 AND UGT ENZYMES / Chapter Part One --- Introduction --- p.85 / Chapter Part Two --- Results --- p.87 / Chapter I. --- Perillyl alcohol and limonene modulated DMBA-induced CYP1A1/1B1 activities in MCF-7 cells --- p.87 / Chapter II. --- Perillyl alcohol and limonene regulated microsomal CYP1A1/1B1 activities --- p.89 / Chapter III. --- Perillyl alcohol and limonene regulated DMBA-induced DNA adduct formation in MCF-7 cells --- p.93 / Chapter IV. --- Perillyl alcohol and limonene regulated CYP1A1 & CYP1B1 gene expressions in MCF-7 cells --- p.95 / Chapter V. --- Effect of perillyl alcohol on CYP1A1 XRE transactivation --- p.97 / Chapter VI. --- Cytotoxic effect of perillyl alcohol and limonene on MCF-7 cells --- p.98 / Chapter VII. --- Perillyl alcohol and limonene modulated UGT1A1 gene expression in MCF-7 cells --- p.99 / Chapter VIII. --- Perillyl alcohol and limonene modulated UGT enzyme in HepG2 cells --- p.101 / Chapter Part Three --- Discussion --- p.106 / Chapter CHAPTER 5 --- LYCOPENE MEDIATED DMBA-INDUCED PHASE I & PHASE II ENZYME ACTIVITIES AND GENE EXPRESSIONS / Chapter Part Three --- Introduction --- p.109 / Chapter I. --- Biochemical properties of lycopene --- p.109 / Chapter II. --- Bioavailability of lycopene --- p.110 / Chapter III. --- Lycopene and cancers in hormonal sensitive tissues --- p.110 / Chapter Part Two --- Results --- p.111 / Chapter I . --- Lycopene modulated DMBA-induced CYP1A1/1B1 activities in MCF-7 cells --- p.111 / Chapter II. --- Lycopene competitively inhibited microsomal CYP1A1 & CYP1B1 activities --- p.113 / Chapter III. --- Lycopene suppressed DMBA-induced DNA adduct formation in MCF-7 cells --- p.115 / Chapter IV. --- Lycopene regulated CYP1A1 & CYP1B1 gene expression in MCF-7 cells --- p.116 / Chapter V. --- Effect of lycopene on CYP1A1 XRE trasactivation --- p.117 / Chapter VI. --- Cytotoxic effect of lycopene on MCF-7 cells --- p.118 / Chapter VII. --- Lycopene modulated UGT enzyme in MCF-7 cells --- p.119 / Chapter VIII. --- Lycopene modulated UGT enzyme in HepG2 cells --- p.121 / Chapter Part Three --- Discussion --- p.123 / Chapter CHAPTER 6 --- CHALCONES AND PERILLYL ALCOHOL REGULATEDCYP1A1 & CYP1B1 MEDIATED ESTRADIOL METABOLIZING PATHWAYS / Chapter Part One --- Introduction --- p.125 / Chapter I . --- Estrogen hydroxylation and human breast cancer risk --- p.125 / Chapter II. --- CYP1 enzymes catalyze estradiol-hydroxylation in human breast cancer cells --- p.126 / Chapter III. --- Phytochemicals mediate estrogen-hydroxylation pathways --- p.126 / Chapter Part Two --- Estrogen metabolite detection and separation by HPLC --- p.127 / Chapter Part Three --- Results --- p.129 / Chapter I . --- Perillyl alcohol modulated CYP1A1 & CYP1B1-mediated Estradiol hydroxylation --- p.129 / Chapter II. --- Kinetics assays of chalcones on CYP1A1 & CYP1B1 microsomes induced estradiol hydroxylation --- p.131 / Chapter III. --- Chalcones suppressed Estradiol-hydroxylase activities in MCF-7 cells --- p.137 / Chapter Part Four --- Discussion --- p.140 / Chapter CHAPTER 7 --- SUMMARY / Chapter I . --- Chalcones displayed inhibitory effects on DMBA-induced carcinogenesis --- p.142 / Chapter II. --- Perillyl alcohol and limonene modulated DMBA-induced carcinogenesis --- p.143 / Chapter III. --- Lycopene also possessed chemoproventive properties --- p.143 / APPENDIX 1 ABBREVIATIONS --- p.144 / APPENDIX 2 REAGENTS --- p.145 / APPENDIX 3 PRIMER LISTS --- p.147 / REFERENCE --- p.148
8

Molecular mechanisms of cell death and cell cycle arrest mediated by cardiac glycosides in cancer cells. / CUHK electronic theses & dissertations collection

January 2012 (has links)
強心苷是一類多年普遍用於心力衰竭治療的化合物,包括蟾蜍靈和地高辛。鈉泵(也可稱為鈉鉀ATP酶)是強心苷的受體。最近流行病學研究,體外實驗,動物實驗和臨床試驗表明,強心苷具有癌症治療的強大潛力。 / 大腸癌是全球第三大殺手,約有一半的大腸癌患者需要手術切除後的輔助治療。因此,通過化療殺死腫瘤細胞,是一個可行的辦法來治療大腸癌患者。在本課題的研究中,強心苷抗人結腸癌的作用在HT-29和Caco-2細胞上進行了評價與闡釋。在結腸癌細胞研究模型中,蟾蜍靈誘導caspase非依賴性的細胞死亡,伴隨沒有早期凋亡,沒有聚(ADP-核糖)聚合酶(PARP)與caspase-3裂解,這些發現與強心苷誘發其它類腫瘤細胞凋亡的機製完全不同。相反,蟾蜍靈激活自噬途徑,促進LC3-II積累和自噬流動。此外,其它強心苷如地高辛與烏本苷也促使LC3-II在HT-29細胞內聚集。沉默ATG5和Beclin-1顯著降低蟾蜍靈誘導的LC3- II積累和細胞死亡。蟾蜍靈誘導的自噬與活性氧(ROS)產生和JNK活化相關。我們的研究結果揭示了蟾蜍靈藥物對抗結腸癌細胞的一種新的機制,開闢了強心苷通過自噬途徑來治療大腸癌的可能性。 / 最近的研究表明,強心苷誘導多種癌細胞系的細胞包括促使凋亡與自噬的細胞週期阻滯在G2/M期。然而,沒有詳細的信息闡述強心苷如何阻滯細胞週期進展。在本課題研究中,我們研究了強心苷介導的細胞週期阻滯的分子機制。蟾蜍靈處理的HeLa H2B-YFP細胞被阻滯在前中期,伴隨姐妹染色單體凝聚,染色體未排列在赤道板,未退出有絲分裂期。這一結果被蟾蜍靈誘導的四倍DNA含量細胞既不在四倍體G1期也不在胞質分裂期進一步證明。此後,我們檢測了紡錘體組裝和染色體分離所需的Aurora激酶和Polo-like kinase 1 (Plk1)。結果發現,在HT-29和HeLa細胞上,蟾蜍靈和其它強心苷能顯著降低總蛋白質和磷酸化的Aurora激酶與Plk1。此外,我們還發現,蟾蜍靈通過PI3K下調有絲分裂酶的活性。這些結果已經通過沉默鈉泵α做了驗證。總之,我們的結果表明, 蟾蜍靈和其它強心苷鈉鉀泵抑製劑強有力的抑制細胞在前中期是通過PI3K/HIF-1α/NF-κB途徑下調Aurora激酶的蛋白質和磷酸化水平和Plk1的蛋白質水平。我們的研究發現在了解如何利用強心苷的潛能治療癌症以及認知鈉泵在細胞週期中的功能方面提供了有用的信息。 / The sodium pump (also known as Na+/K+-ATPase) is the receptor for cardiac glycosides, a group of compounds including bufalin and digoxin which have been commonly used for heart failure treatment for many years. Recent epidemiological studies, in vitro studies, animal studies and clinical trials have shown that cardiac glycosides have potential applications for cancer treatment. / Colorectal cancer is the third leading cause of cancer death worldwide and about half of the patients with colorectal cancer require adjuvant therapy after surgical resection. Therefore, the eradication of cancer cells via chemotherapy constitutes a viable approach to treat patients with colorectal cancer. In this study, the effects of cardiac glycosides were evaluated and characterized in HT-29 and Caco-2 human colon cancer cells. Contrary to their well documented apoptosis-promoting activity in other cancer cells, bufalin did not cause caspase-dependent cell death in colon cancer cells, as indicated by the absence of significant early apoptosis, as well as poly(ADP-ribose) polymerase (PARP) and caspase-3 cleavage. Instead, bufalin activated an autophagy pathway, as characterized by the accumulation of LC3-II and the stimulation of autophagic flux. Moreover, other cardiac glycosides digoxin and ouabain could also induce the accumulation of LC3-II in HT-29 cells. The silencing of ATG5 and Beclin-1 significantly reduced bufalin-induced LC3-II accumulation and cell death. The induction of autophagy by bufalin was linked to the generation of reactive oxygen species (ROS) and JNK activation. My findings unveil a novel mechanism of drug action by bufalin in colon cancer cells and open up the possibility of treating colorectal cancer by cardiac glycosides through an autophagy pathway. / Recent studies have revealed that cardiac glycosides induce G2/M phase arrest in many cancer cells, which include apoptosis- and autophagy-promoting cells. However, no detailed information is available on how cardiac glycosides arrest cell cycle progression. In this study, I studied the molecular mechanisms of cell cycle arrest mediated by cardiac glycosides. Bufalin-treated HeLa H2B-YFP cells were arrested at prometaphase, as characterized by the presence of sister chromatid cohesion, absence of chromosomes alignment on the metaphase plate, and failure to exit mitosis. This result was further confirmed by bufalin-induced cells with 4N DNA content in neither tetraploid G1 phase nor cytokinesis. Thereafter, I detected the Aurora kinases and Polo-like kinase 1 (Plk1), which are required for both spindle assembly and chromosome segregation. It was found that bufalin and other cardiac glycosides could significantly reduce the total protein and phosphorylation of Aurora kinases and Plk1 in HT-29 and HeLa cells. In addition, I found that PI3K was responsible for the bufalin-induced downregulation of the activities of mitotic kinases. This result was validated by silencing of sodium pump alpha. Taken together, my results demonstrate that bufalin and other cardiac glycoside inhibitors of the sodium pump potently arrest cancer cells at prometaphase by downregulating the total protein and phosphorylation of Aurora kinases and the total protein of Plk1 through the PI3K/HIF-1α/NF-κB pathway. My findings provide useful information in understanding how cardiac glycosides could be exploited for their potentials in treating cancer and in identifying the function of sodium pump in cell cycle progression. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Xie, Chuanming. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 133-152). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Declaration of Originality --- p.i / Acknowledgements --- p.iii / Abstract --- p.vi / Abstract (in Chinese) --- p.viii / List of Abbreviations --- p.xiv / List of Figures --- p.xvi / List of Tables --- p.xix / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Cancer --- p.1 / Chapter 1.2 --- The chemical structure of cardiac glycosides --- p.2 / Chapter 1.3 --- The traditional use of cardiac glycosides in cardiology --- p.4 / Chapter 1.4 --- The role of cardiac glycosides in cancer treatment --- p.4 / Chapter 1.5 --- The mechanisms of action by cardiac glycosides in cancer --- p.5 / Chapter 1.5.1 --- The structure and functions of cardiac glycosides receptor sodium pump --- p.5 / Chapter 1.5.2 --- Sodium pump as anticancer target --- p.6 / Chapter 1.5.3 --- The signal pathways involved in anticancer effect of cardiac glycosides --- p.7 / Chapter 1.6 --- The role of cardiac glycosides in apoptosis and autophagy --- p.8 / Chapter 1.7 --- Objectives of this project --- p.12 / Chapter Chapter 2 --- Bufalin induces autophagy but not apoptosis in human colon cancer cells --- p.17 / Chapter 2.1 --- Introduction --- p.17 / Chapter 2.2 --- Materials and Methods --- p.19 / Chapter 2.2.1 --- Reagents and antibodies --- p.19 / Chapter 2.2.2 --- Cell culture --- p.19 / Chapter 2.2.3 --- Cell viability and cell death assay --- p.20 / Chapter 2.2.4 --- Annexin V and PI staining --- p.20 / Chapter 2.2.5 --- Cell cycle analysis --- p.21 / Chapter 2.2.6 --- Analysis of cleaved caspase-3-positive cells by flow cytometry --- p.21 / Chapter 2.2.7 --- Western blot analysis --- p.21 / Chapter 2.2.8 --- Immunofluorescence analysis of LC3 distribution --- p.22 / Chapter 2.2.9 --- RNA isolation and RT-PCR --- p.22 / Chapter 2.2.10 --- siRNAs transfection and treatments --- p.23 / Chapter 2.2.11 --- Transmission electron microscopy --- p.23 / Chapter 2.2.12 --- Statistical analysis --- p.24 / Chapter 2.3 --- Results --- p.24 / Chapter 2.3.1 --- Bufalin induces cell death and cell cycle arrest at G2/M phase in colon cancer cells --- p.24 / Chapter 2.3.2 --- Bufalin induces caspase-independent cell death in colon cancer cells --- p.28 / Chapter 2.3.3 --- Bufalin induces autophagy in colon cancer cells --- p.30 / Chapter 2.3.4 --- Bufalin-induced autophagy is dependent on ATG5 and Beclin-1 --- p.37 / Chapter 2.3.5 --- Increased autophagy is responsible for bufalin-induced cell death --- p.40 / Chapter 2.4 --- Discussion --- p.42 / Chapter Chapter 3 --- Bufalin mediates autophagic cell death through ROS generation and JNK activation --- p.44 / Chapter 3.1 --- Introduction --- p.44 / Chapter 3.2 --- Materials and Methods --- p.46 / Chapter 3.2.1 --- Reagents and antibodies --- p.46 / Chapter 3.2.2 --- Cell culture --- p.47 / Chapter 3.2.3 --- Cell viability and cell death assay --- p.47 / Chapter 3.2.4 --- Western blot analysis --- p.47 / Chapter 3.2.5 --- Quantification of cells with > 5 LC3 punctate staining --- p.47 / Chapter 3.2.6 --- siRNAs transfection and treatments --- p.48 / Chapter 3.2.7 --- RNA isolation and RT-PCR --- p.48 / Chapter 3.2.8 --- ROS analysis --- p.48 / Chapter 3.2.9 --- JC-1 staining --- p.49 / Chapter 3.2.10 --- Statistical analysis --- p.49 / Chapter 3.3 --- Results --- p.50 / Chapter 3.3.1 --- Bufalin induces autophagy-mediated cell death via ROS generation --- p.50 / Chapter 3.3.2 --- Activation of JNK is required for the upregulation of ATG5 and Beclin-1, and subsequent autophagy-mediated cell death in response to bufalin --- p.54 / Chapter 3.3.3 --- ROS generation is upstream of JNK activation in bufalin-induced cell death --- p.59 / Chapter 3.3.4 --- Bufalin-induced ROS generation is derived from mitochondria --- p.62 / Chapter 3.4 --- Discussion --- p.66 / Chapter Chapter 4 --- Bufalin arrests cells at prometaphase --- p.69 / Chapter 4.1 --- Introduction --- p.69 / Chapter 4.2 --- Materials and Methods --- p.70 / Chapter 4.2.1 --- Reagents and antibodies --- p.70 / Chapter 4.2.2 --- Cell synchronization --- p.70 / Chapter 4.2.3 --- Mitotic index analysis of phosphorylation of MPM2 --- p.71 / Chapter 4.2.4 --- Cell cycle analysis --- p.71 / Chapter 4.2.5 --- Time-lapse experiments --- p.71 / Chapter 4.2.6 --- Immunofluorescence analysis of phospho-histone H3 (Ser10) --- p.72 / Chapter 4.2.7 --- Western blot analysis --- p.73 / Chapter 4.3 --- Results --- p.73 / Chapter 4.3.1 --- Bufalin reduces mitotic marker phosphorylation of histone H3 and MPM2 and increases cells with 4N DNA content --- p.73 / Chapter 4.3.2 --- Increased cells with 4N DNA content after bufalin treatment are in neither a tetraploid G1 phase nor a cytokinesis arrest --- p.77 / Chapter 4.3.3 --- Bufalin-treated cells can enter prophase, but fail to pass through metaphase --- p.80 / Chapter 4.4 --- Discussion --- p.83 / Chapter Chapter 5 --- Bufalin induces prometaphase arrest through downregulating mitotic kinases --- p.87 / Chapter 5.1 --- Introduction --- p.87 / Chapter 5.2 --- Materials and Methods --- p.89 / Chapter 5.2.1 --- Reagents and antibodies --- p.89 / Chapter 5.2.2 --- Cell synchronization --- p.90 / Chapter 5.2.3 --- Immunofluorescence staining --- p.90 / Chapter 5.2.4 --- siRNAs transfection and treatments --- p.91 / Chapter 5.2.5 --- Western blot analysis --- p.91 / Chapter 5.2.6 --- Statistic analysis --- p.91 / Chapter 5.3 --- Results --- p.92 / Chapter 5.3.1 --- Bufalin downregulates Aurora A and B in protein and phosphorylation levels --- p.92 / Chapter 5.3.2 --- Bufalin prevents Aurora A recruitment to mitotic centrosomes and Aurora B recruitment to unattached kinetochores --- p.97 / Chapter 5.3.3 --- Bufalin prevents Plk1 recruitment to mitotic centrosomes and unattached kinetochores through downregulation of protein levels of Plk1 --- p.101 / Chapter 5.3.4 --- Bufalin decreases the activities of Aurora A, Aurora B and Plk1 through PI3K pathway --- p.105 / Chapter 5.3.5 --- HIF-1α and NF-κB pathways are involved in sodium pump-mediated the regulation of mitotic kinases --- p.109 / Chapter 5.4 --- Discussion --- p.112 / Chapter Chapter 6 --- General discussion --- p.115 / Chapter 6.1 --- Potential toxicity of bufalin --- p.115 / Chapter 6.2 --- Cardiac glycosides induced programmed cell death --- p.115 / Chapter 6.3 --- Signal pathways involved in cardiac glycosides-mediated autophagy --- p.117 / Chapter 6.4 --- The relationship between ROS and JNK in cardiac glycosides-induced autophagy --- p.120 / Chapter 6.5 --- The role of ROS in apoptosis and autophagy --- p.121 / Chapter 6.6 --- The role of cardiac glycosides in cell cycle arrest --- p.122 / Chapter 6.7 --- Application of cardiac glycosides in combination with chemotherapy and radiotherapy --- p.125 / Chapter Chapter 7 --- Conclusions and future perspectives --- p.127 / References --- p.133 / Appendices --- p.153 / Publication --- p.153
9

A rice bran polyphenol, cycloartenyl ferulate, triggers caspase-dependent apoptosis in human colon cancer cells. / CUHK electronic theses & dissertations collection

January 2009 (has links)
Findings from this pioneer study demonstrate that CF, which is unique to rice bran oil, is capable of triggering apoptosis in CRC cells at early stages of carcinogenesis. Furthermore, CF enhances TRAIL-induced apoptosis in metastatic CRC cells. This study provides clear evidence that the health-beneficial properties of whole grain consumption are not only limited by the presence of dietary fiber but also other molecules that can either act as a chemopreventive agent to directly induce tumor regression or a sensitizer to enhance TRAIL-induced apoptosis in metastatic cancer cells. / High intake of whole grain food has been suggested as an important factor for reducing the risk of colon cancer, owing to the abundance of indigestible fiber. Rice bran, which is a component of raw rice after removal of starchy endosperm in milling process, has been shown to be a rich source of some health-beneficial compounds for preventing cancer, hyperlipidaemia, fatty liver, hypercalciuria, kidney stones, and heart disease (Jariwalla, 2001). In the present study, proliferation-inhibitory effects of some rice bran polyphenolic compounds were investigated on a panel of human colorectal cancer (CRC) cell lines, including SW480 (stage B), SW620 (stage C) and Colo-201 (stage D) with increasing metastatic potential according to the Dukes' classification system. / Results from the MTT study revealed that, among the polyphenolic compounds tested, cycloartenyl ferulate (CF) showed the most prominent proliferation inhibition on the CRC cells. CF is one of the typical ferulic acid esters of triterpene alcohols present in rice bran oil. The cancer cell proliferation was reduced by 62, 31 and 21% of their control levels after 72 h of 200 muM CF treatment, respectively. CF seemed to possess higher ability to control proliferation of tumor cells at early stages of cancer development. In meanwhile, results from Toxilight study showed that CF had low toxicity on normal colon CCD-18-Co cells. The anticancer activity of CF was further illustrated by its ability to induce significant regression of SW480 xenograft in nude mice. CF was found to induce apoptosis in SW480 cells in vitro. DNA flow cytometric studies demonstrated that CF elevated dose- and time-dependently the sub G1 or apoptotic cells with fragmented DNA. The pro-apoptotic effect of CF was further confirmed using immunoblotting study showing cleavage of poly(ADP-ribose) polymerase (PARP), which is a hallmark feature of apoptosis. Besides, the executioner procaspase-3, -6 and -7 were found to be processed and activated. On the other hand, administration of pan-caspase inhibitor Z-VAD-FMK completely rescued the cells from PARP cleavage, indicating that CF elicited solely caspase-dependent apoptosis. Elevation of death receptors DR4 and DR5 with the CF treatment seems to originate the upstream activation of the initiator procaspase-8 and -10 of the extrinsic apoptosis pathway. Flow cytometric JC-1 studies further demonstrated that CF significantly altered the mitochondrial membrane potential in a dose-dependent manner together with cytochrome c and smac/DIABLO but not AIF release from mitochondria into the cytosol, as well as the activation of procaspase-9 of the intrinsic apoptosis pathway. Depletion of anti-apoptotic Bcl-2 and elevation of pro-apoptotic Bak were observed; meanwhile, Bid was found to be cleaved by caspase-8, so that the death receptor pathway might be exaggerated by the mitochondrial apoptosis pathway. / Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) is a promising candidate for cancer therapeutics due to its ability to induce apoptosis selectively in cancer cells (Gura, 1997). Result from MTT study illustrated that SW620 was more resistant than SW480 to TRAIL treatment. It is recognized that SW620 is the metastatic form of SW480 derived from the same patient at a later time, so it is important to develop agents that are able to sensitize the cancer cells to TRAIL, or to recover TRAIL sensitivity. We show for the first time that CF sensitizes SW620 cells to TRAIL-induced apoptosis and the mechanisms involved at least elevation of DR4, enhanced activation of caspase-8 and -3, as well as increase in DNA fragmentation. / Kong, Ka Lai. / Adviser: Wong Yum Shing. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 119-136). / 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, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
10

Teste de papanicolaou: construção e validação de material educativo para usuárias de serviços de saúde / Papanicolaou test: construction and validation of educational material health service users

Gonçales, Marlene Bueno [UNIFESP] January 2007 (has links) (PDF)
Made available in DSpace on 2015-12-06T23:47:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2007 / O câncer de colo de útero é o mais comum entre as mulheres no mundo. No Brasil, estima-se que seja a terceira neoplasia maligna encontrada entre mulheres. Pode ser prevenido se for detectado precocemente, há necessidade de sua conscientização por meio da educação em saúde, que pode auxiliar as mulheres a terem maior autonomia sobre seu corpo e saúde. Com o propósito de contribuir para a melhoria na promoção da saúde de mulher, este trabalho teve o objetivo de construir e validar material educativo com orientações passo a passo sobre a importância e realização do exame de Papanicolaou para usuárias de serviços públicos de saúde da cidade de São Paulo/Brasil. Trata-se de pesquisa descritiva, exploratória e observacional que se propôs construir um folder com orientações para prevenção do câncer cérvico-uterino para mulheres, tendo como referencial teórico a educação de adultos. Sua construção foi realizada com as mulheres, utilizando-se linguagem e desenhos de fácil compreensão. Foi avaliado por oito profissionais especialistas na área. Realizadas as modificações sugeridas, ele foi reproduzido e validado por 96 usuárias de unidades básicas de saúde da cidade de São Paulo. Os resultados da validação revelam que as mulheres consideraram por unanimidade o texto interessante com frases de fácil compreensão, ilustrações simples que facilitaram seu entendimento. A grande maioria teve o interesse em ler o folder até o final que as fez repensar sobre sua saúde. As mulheres expressaram a boa qualidade do material, verbalizando o interesse em levá- lo para casa. Concluiu-se que o material educativo construído e validado poderá colaborar na produção do conhecimento das mulheres que freqüentam unidades de saúde e contribuir para o recrutamento da população para realização desse exame simples e indispensável para prevenção do câncer cérvico-uterino com o objetivo de contribuir para diminuição dos índices de morbimortalidade feminino por câncer. / The cancer of the cervix of the uterus is the most common among the women in the world. In Brazil, it is supposed to be the third malignant neoplasia found among women. It can be prevented if detected precociously. It is necessary to aware people through health education so that it can help women to be more autonomous concerning their body and health. With the purpose of contributing to improvement in women health promotion, this paper had the aim of building and validating educational material with step by step orientations about the importance and accomplishment of Papanicolaou exam to public health service users of São Paulo city in Brazil. It is a descriptive, exploratory and observational research with the purpose of developing a folder with orientation about the cancer of the uterine cervix to women, having as theoretical reference the adults' education. Its production was done with women, using language and drawings easily understood. It was analyzed by eight specialists in the area. After the proper changes, the folder was printed and validated by 96 users of the basic health units of São Paulo city. The results of acceptance reveal that all the women considered the text interesting with easy understandable sentences and simple illustration which helped their comprehension. The majority was interested in reading the text until the end which made them to rethink their health. The women expressed the good quality of the material when they said they were interested in taking it home. It was concluded that the educational material produced and validated will be able to help in the knowledge production of women that usually go to health public bases and contribute to the population recruiting and accomplishment of this simple and indispensable exam to uterine cervical cancer that must help a lot to minimize the female diseases and mortality rates by cancer. / BV UNIFESP: Teses e dissertações

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