by Joyce Chui Kwan Ho. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 61-75). / Abstracts in English and Chinese. / Acknowledgments --- p.i / List of Abbreviations --- p.iii / Abstract / English --- p.1 / Chinese --- p.2 / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Tumor Formation --- p.3 / Chapter 1.2 --- Anti-tumor Pathways --- p.4 / Chapter 1.3 --- Aim of Project --- p.13 / Chapter Chapter 2 --- The In Vivo effect of Polysaccharopeptide / Chapter 2.1 --- Introduction --- p.15 / Chapter 2.2 --- Materials and Methods --- p.17 / Chapter 2.3 --- Results --- p.18 / Chapter 2.4 --- Discussion --- p.19 / Chapter Chapter 3 --- Cytotoxicity / Chapter 3.1 --- Introduction --- p.23 / Chapter 3.2 --- Materials and Methods --- p.26 / Chapter 3.3 --- Results --- p.28 / Chapter 3.4 --- Discussion --- p.28 / Chapter Chapter 4 --- Anti-angiogenic Effect / Chapter 4.1 --- Introduction --- p.30 / Chapter 4.2 --- Materials and Methods --- p.35 / Chapter 4.3 --- Results --- p.39 / Chapter 4.4 --- Discussion --- p.42 / Chapter Chapter 5 --- Immunomodulation / Chapter 5.1 --- Introduction --- p.45 / Chapter 5.2 --- Materials and Methods --- p.47 / Chapter 5.3 --- Results --- p.50 / Chapter 5.4 --- Discussion --- p.52 / Chapter Chapter 6 --- General Discussion --- p.57 / References --- p.61

by Cheung Yuen-Nei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 194-208). / Abstracts in English and Chinese. / Acknowledgement --- p.i / Abstract --- p.ii / 摘要 --- p.iv / Contents --- p.vi / List of Figures --- p.xii / List of Tables --- p.xv / Abbreviations --- p.xvi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1 --- Introduction --- p.2 / Chapter 1.1 --- Characteristic of Saponins --- p.3 / Chapter 1.1.1 --- Occurrence of Saponins --- p.3 / Chapter 1.1.2 --- General Properties of Saponins --- p.3 / Chapter 1.1.2.1 --- Emulsifying Agents --- p.3 / Chapter 1.2.2.2 --- Forming Complex with Cholesterol --- p.4 / Chapter 1.1.2.3 --- Hemolytic Property --- p.4 / Chapter 1.1.3 --- Structure of Saponins --- p.5 / Chapter 1.1.3.1 --- Categories of Saponins --- p.5 / Chapter 1.1.3.1.1 --- Triterpene Saponins --- p.5 / Chapter 1.1.3.1.2 --- Steroid Saponins --- p.5 / Chapter 1.1.3.2 --- Monodesmosidic and Bidesmosidic Saponins --- p.7 / Chapter 1.1.4 --- Biological and Pharmacological Properties of Saponins --- p.9 / Chapter 1.1.4.1 --- Anti-microbial Activity --- p.9 / Chapter 1.1.4.1.1 --- Anti-fungal Activities --- p.9 / Chapter 1.1.4.1.2 --- Anti-bacterial Activities --- p.10 / Chapter 1.1.4.1.3 --- Anti-viral Activities --- p.10 / Chapter 1.1.4.2 --- Insecticidal Activity --- p.10 / Chapter 1.1.4.3 --- Molluscicidal Activity --- p.10 / Chapter 1.1.4.4 --- Hypocholesterolemic Activity --- p.11 / Chapter 1.1.4.5 --- Anti-ulcer Activity --- p.11 / Chapter 1.1.4.6 --- Contraceptive Activity --- p.12 / Chapter 1.1.4.7 --- Immunomodulatory Activities --- p.12 / Chapter 1.1.4.7.1 --- Direct Immunostimulation --- p.12 / Chapter 1.1.4.7.2 --- Acting as Immuno-adjuvants --- p.13 / Chapter 1.1.4.8 --- Anti-tumor Activity --- p.14 / Chapter 1.1.4.8.1 --- Anti-carcinogenesis --- p.15 / Chapter 1.1.4.8.2 --- Suppression of Tumor Growth --- p.16 / Chapter 1.1.5 --- Anti-tumor Activity of Steroid Saponins --- p.18 / Chapter 1.1.5.1 --- Diosgenin Steroid Saponin --- p.18 / Chapter 1.1.5.2 --- Hong Kong Compounds --- p.18 / Chapter 1.1.5.3 --- Hong Kong18 --- p.21 / Chapter 1.2 --- Human Hepatocellular Carcinoma (HCC) --- p.24 / Chapter 1.2.1 --- The Incidence of Liver Cancer --- p.24 / Chapter 1.2.2 --- Classification of Liver Cancer --- p.24 / Chapter 1.2.3 --- Human Hepatocellular Carcinoma Cell Lines --- p.25 / Chapter 1.2.3.1 --- Human Hepatocellular Carcinoma Cell Line HepG2 --- p.25 / Chapter 1.2.3.2 --- Multidrug Resistant Human Hepatocellular Carcinoma Cell Line R-HepG2 --- p.27 / Chapter 1.2.3.2.1 --- Mechanisms of Multidrug Resistance --- p.28 / Chapter 1.2.3.2.2 --- Structure and Characteristics of P-glycoprotein --- p.29 / Chapter 1.2.3.2.3 --- Methods in Dealing with P-glycoprotein Over-expressed MDR Cells --- p.31 / Chapter 1.3 --- Objectives of the Project --- p.32 / Chapter 1.3.1 --- Study of the Anti-tumor Activities of Hong Kong 18 on Human Hepatocellular Carcinoma Cell Line HepG2 and Unravel the Underlying Mechanisms --- p.32 / Chapter 1.3.2 --- Study of the Anti-tumor Activities of Hong Kong 18on Multidrug Resistant Human Hepatocellular Carcinoma Cell Line R-HepG2 and Unravel the Underlying Mechanisms --- p.32 / Chapter Chapter 2 --- Materials and Methods --- p.33 / Chapter 2.1 --- Materials --- p.34 / Chapter 2.1.1 --- Cell Culture --- p.34 / Chapter 2.1.1.1 --- Cell Lines --- p.34 / Chapter 2.1.1.2 --- Culture Media --- p.35 / Chapter 2.1.2 --- Reagents and Buffers --- p.36 / Chapter 2.1.2.1 --- Phosphate Buffered Saline (PBS) --- p.36 / Chapter 2.1.2.2 --- Reagents and Buffers for DNA Fragmentation --- p.36 / Chapter 2.1.2.3 --- Reagents and Buffers for Western Analysis --- p.37 / Chapter 2.1.2.4 --- Reagents and Buffer for Caspases Activities --- p.39 / Chapter 2.1.2.5 --- Fluorescent Dyes used for Flow Cytometry --- p.39 / Chapter 2.1.3 --- Chemicals --- p.39 / Chapter 2.2 --- Methods --- p.46 / Chapter 2.2.1 --- MTT Assay --- p.46 / Chapter 2.2.2 --- Determination of Cell Viability --- p.46 / Chapter 2.2.3 --- Purification of Macrophages from balb/c Mice --- p.47 / Chapter 2.2.4 --- Hemolysis Assay --- p.47 / Chapter 2.2.5 --- In vivo Studies of the Toxicity of HK18 --- p.48 / Chapter 2.2.6 --- DNA Fragmentation Assay --- p.50 / Chapter 2.2.7 --- Detection of Apoptotic and Necrotic / Late Apoptotic Cells Death by Flow Cytometry with Annexin V-FITC / PI --- p.51 / Chapter 2.2.8 --- Detection of Mitochondrial Membrane Potential by JC-1 Fluorescent Dye --- p.52 / Chapter 2.2.9 --- Detection of Intracellular Ca Level by Flow Cytometry with Fluo-3 Fluorescent Dye --- p.52 / Chapter 2.2.10 --- Detection of Intracellular Hydrogen Peroxide Level by Flow Cytometry with DCF Fluorescence Dye --- p.53 / Chapter 2.2.11 --- Simultaneous Detection of Mitochondrial Membrane Potential and Intracellular Ca2+ or Mitochondrial Membrane Potential and Intracellular Hydrogen Peroxide --- p.54 / Chapter 2.2.12 --- Western Analysis --- p.55 / Chapter 2.2.12.1 --- Total Protein Extraction --- p.55 / Chapter 2.2.12.2 --- Extraction of Cytosolic Proteins --- p.59 / Chapter 2.2.13 --- Determination of Caspases Enzymatic Activity --- p.63 / Chapter 2.2.14 --- Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) --- p.67 / Chapter 2.2.14.1 --- RNA Extraction by TRIzol Reagent --- p.67 / Chapter 2.2.14.2 --- Reverse Transcription --- p.68 / Chapter 2.2.14.3 --- Polymerase Chain Reaction --- p.68 / Chapter 2.3 --- Statistic Analysis --- p.71 / Chapter Chapter 3 --- Cytotoxicity of HK18 --- p.72 / Chapter 3.1 --- Cytotoxicity of HK18 on HepG2 Cells --- p.73 / Chapter 3.1.1 --- Study of the Cytotoxic Activity of HK18 on HepG2 Cells by MTT Assay --- p.73 / Chapter 3.1.2 --- Study of the Cytotoxic Activity of HK18 on HepG2 Cells by Tryphan Blue Exclusion Assay --- p.76 / Chapter 3.2 --- Cytotoxicity of HK18 on R-HepG2 Cells --- p.78 / Chapter 3.2.1 --- Study of the Cytotoxic Activity of HK18 on R-HepG2 Cells by MTT Assay --- p.78 / Chapter 3.2.2 --- Study of the Cytotoxic Activity of HK18 on R-HepG2 Cells by Tryphan Blue Exclusion Assay --- p.81 / Chapter 3.3 --- Cytotoxicity of HK18 on Macrophages --- p.83 / Chapter 3.4 --- Hemolytic Activity of HK18 --- p.85 / Chapter 3.5 --- In vivo Study of the Toxicity of HK18 --- p.87 / Chapter Chapter 4 --- Mechanistic Study of HK18 on HepG2 Cells --- p.90 / Chapter 4.1 --- Hallmarks of Apoptosis Induced by HK18 on HepG2 Cells --- p.91 / Chapter 4.1.1 --- Induction of Phosphatidylserine Externalization by HK18 on HepG2 Cells --- p.91 / Chapter 4.1.2 --- Induction of DNA Fragmentation by HK18 of HepG2 Cells --- p.97 / Chapter 4.2 --- Study of the Underlying Mechanisms of HK18 Induced Apoptosis in HepG2 Cells --- p.99 / Chapter 4.2.1 --- The Role of Mitochondria in HK18 Induced Apoptosis of HepG2 Cells --- p.99 / Chapter 4.2.1.1 --- HK18 Induced Mitochondrial Membrane Depolarization in HepG2 Cells --- p.101 / Chapter 4.2.1.2 --- Addition of Bongkrekic Acid Reduced HK18 Cytotoxicity on HepG2 Cells --- p.105 / Chapter 4.2.1.3 --- Elevation of Intracellular Hydrogen Peroxide Level in HK18 Treated HepG2 Cells --- p.108 / Chapter 4.2.1.4 --- Elevation of Intracellular Ca2+ Level in HK18 Treated HepG2 Cells --- p.114 / Chapter 4.2.1.5 --- HK18 Induced Cytochrome c and AIF Released from Mitochondria of HepG2 Cells --- p.120 / Chapter 4.3 --- Downstream Biochemical Changes Induced by HK18 on HepG2 Cells --- p.123 / Chapter 4.3.1 --- Activation of Caspase 3 of HepG2 Cells by HK18 as Demonstrated by Western Blot --- p.123 / Chapter 4.3.2 --- Induction of Caspases Activities of HepG2 Cells by HK18 as Demonstrated by Enzymatic Activity Assays --- p.125 / Chapter 4.4 --- Down-regulation of Anti-apoptotic Bcl-2 Family Members of HepG2 Cells by HK18 --- p.129 / Chapter Chapter 5 --- Mechanistic Study of HK18 on R-HepG2 Cells --- p.133 / Chapter 5.1 --- Hallmarks of Apoptosis Induced by HK18 on R-HepG2 Cells --- p.134 / Chapter 5.1.1 --- Induction of Phosphatidylserine Externalization by HK18 on R-HepG2 Cells --- p.134 / Chapter 5.1.2 --- Induction of DNA Fragmentation by HK18 of R-HepG2 Cells --- p.137 / Chapter 5.2 --- Study of the Underlying Mechanisms of HK18 Induced Apoptosis in R-HepG2 Cells --- p.139 / Chapter 5.2.1 --- The Role of Mitochondria in HK18 Induced Apoptosis of R-HepG2 Cells --- p.139 / Chapter 5.2.1.1 --- HK18 Induced Mitochondrial Membrane Depolarization in R-HepG2 Cells --- p.139 / Chapter 5.2.1.2 --- Addition of Bongkrekic Acid Reduced HK18 Cytotoxicity on R-HepG2 Cells --- p.142 / Chapter 5.2.1.3 --- Elevation of Intracellular Hydrogen Peroxide Level in HK18 Treated R-HepG2 Cells --- p.144 / Chapter 5.2.1.4 --- Elevation of Intracellular Ca2+ Level in HK18 Treated R-HepG2 Cells --- p.146 / Chapter 5.3 --- Downstream Biochemical Changes Induced by HK18 on R-HepG2 Cells --- p.148 / Chapter 5.3.1 --- Activation of Caspase 3 of R-HepG2 Cells by HK18 as Demonstrated by Western Blot --- p.148 / Chapter 5.3.2 --- Induction of Caspases Activation of R-HepG2 Cells by HK18 as Demonstrated by Enzymatic Activity Assays --- p.150 / Chapter 5.4 --- Down-regulation of the Anti-apoptotic Bcl-2 Protein of R-HepG2 Cells by HK18 --- p.154 / Chapter 5.5 --- HK18 was Not a Substrate of P-glycoprotein Contents --- p.156 / Chapter Chapter 6 --- Discussion --- p.158 / Chapter 6.1 --- Cytotoxicity of HK18 --- p.159 / Chapter 6.1.1 --- HK18 was Cytotoxic to the Human Hepatocellular Carcinoma Cell Line HepG2 and Multidrug Resistant Human Hepatocellular Carcinoma Cell Line R-HepG2 --- p.159 / Chapter 6.1.2 --- Study of the Toxicity of HK18 --- p.160 / Chapter 6.2 --- Mechanistic Studies of the Cytotoxic Effects of HK18 on HepG2 Cells --- p.161 / Chapter 6.2.1 --- Apoptotic Cell Death Induction of HK18 on HepG2 Cells --- p.161 / Chapter 6.2.2 --- Studies of the Underlying Mechanisms of HK18 Induced Apoptosis of HepG2 Cells --- p.162 / Chapter 6.3 --- Mechanistic Studies of the Cytotoxic Effects of HK18 on R-HepG2 Cells --- p.181 / Chapter 6.3.1 --- Apoptotic Cell Death Induction of HK18 on R-HepG2 Cells --- p.181 / Chapter 6.3.2 --- Studies of the Underlying Mechanisms of HK18 Induced Apoptosis of HepG2 Cells --- p.181 / Chapter Chapter 7 --- Future Perspectives --- p.190 / Chapter Chapter 8 --- References --- p.193

by Ko Samuel. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 209-227). / Abstract also in Chinese. / Acknowledgements --- p.i / Abbreviations --- p.ii / Abstract --- p.vii / Abstract in Chinese --- p.x / List of Figures --- p.xiii / List of Tables --- p.xx / Publication --- p.xxi / Contents --- p.xxii / Chapter Chapter 1. --- General Introduction --- p.1 / Chapter 1.1 --- Tumor Necrosis Factor --- p.2 / Chapter 1.1.1 --- History of Tumor Necrosis Factor --- p.2 / Chapter 1.1.2 --- TNF Subtypes and Their Purification --- p.3 / Chapter 1.1.3 --- Release of TNF --- p.9 / Chapter 1.1.4 --- Biological Actions of TNF --- p.9 / Chapter 1.2 --- Tumor Necrosis Factor Receptor --- p.11 / Chapter 1.2.1 --- Purification of TNF Receptor --- p.11 / Chapter 1.2.2 --- Regulation of TNF Receptor --- p.14 / Chapter 1.2.3 --- "Functions of TNF Receptor 1,Receptor 2 and Soluble TNF Receptors" --- p.15 / Chapter 1.3 --- Possible Signal Transductions of Tumor Necrosis Factor-Alpha --- p.17 / Chapter 1.3.1 --- Activation of Phospholipase A2 Cascade --- p.18 / Chapter 1.3.2 --- Activation of Phospho lipase C Pathway --- p.19 / Chapter 1.3.3 --- Activation of Sphingomyelin Pathway --- p.20 / Chapter 1.3.4 --- Activation of Protein Kinase --- p.22 / Chapter 1.3.5 --- Activation of the Cascade of Death Domain --- p.23 / Chapter 1.4 --- Induction of Both Necrosis and Apoptosis by Tumor Necrosis Factor-Alpha --- p.25 / Chapter 1.4.1 --- Apoptosis Versus Necrosis --- p.25 / Chapter 1.4.2 --- TNF Can Induce Both Apoptosis and Necrosis --- p.27 / Chapter 1.5 --- Possible Mechanisms of Tumor Necrosis Factor-Alpha- Mediated Cytotoxicity --- p.27 / Chapter 1.5.1 --- Release of Reactive Oxygen Species --- p.28 / Chapter 1.5.2 --- Release of Intracellular Calcium --- p.31 / Chapter 1.5.3 --- Miscellaneous Mechanisms --- p.36 / Chapter 1.6 --- Objective of Studies --- p.37 / Chapter Chapter 2. --- Materials and Methods --- p.39 / Chapter 2.1 --- Materials --- p.40 / Chapter 2.1.1 --- Buffer --- p.40 / Chapter 2.1.2 --- Culture Media --- p.45 / Chapter 2.1.3 --- Chemicals --- p.46 / Chapter 2.1.4 --- Culture of Cells --- p.49 / Chapter 2.1.4.1 --- "Tumor Necrosis Factor-Alpha-Sensitive Cell Line, L929" --- p.49 / Chapter 2.1.4.2 --- "Tumor Necrosis Factor-Alpha-Resistant Cell Line, rL929, rL929-l IE and rL929-4F" --- p.50 / Chapter 2.2 --- Methods --- p.50 / Chapter 2.2.1 --- Agarose Gel Electrophoresis --- p.50 / Chapter 2.2.2 --- Cytotoxicity Assay --- p.52 / Chapter 2.2.3 --- Confocal Laser Scanning Microscopy --- p.53 / Chapter 2.2.4 --- Flow Cytometry --- p.57 / Chapter Chapter 3. --- Results --- p.65 / Chapter 3.1 --- Induction of Apoptosis in Tumor Necrosis Factor-Alpha- Treated L929 Cell --- p.66 / Chapter 3.1.1 --- Introduction --- p.66 / Chapter 3.1.2 --- TNF Induced DNA Fragmentation in L929 Cells --- p.67 / Chapter 3.2 --- Effect of Tumor Necrosis Factor-Alpha on Cell Cycle --- p.73 / Chapter 3.2.1 --- Introduction --- p.73 / Chapter 3.2.2 --- Effect of TNF on Cell Cycle --- p.75 / Chapter 3.3 --- Release of Reactive Oxygen Species in Tumor Necrosis Factor-Alpha Treatment --- p.79 / Chapter 3.3.1 --- Introduction --- p.79 / Chapter 3.3.2 --- Release of Reactive Oxygen Species in TNF- Treated L929 Cells is Time Dependent --- p.81 / Chapter 3.3.3 --- Effect of Antioxidants on TNF-Mediated Cytotoxicity --- p.93 / Chapter 3.3.4 --- Effect of Mitochondrial Inhibitors on TNF-Mediated Cytotoxicity --- p.96 / Chapter 3.4 --- The Role of Calcium in Tumor Necrosis Factor-Alpha Treatment --- p.112 / Chapter 3.4.1 --- Introduction --- p.112 / Chapter 3.4.2 --- Release of Intracellular Calcium in TNF-Treated L929 Cells --- p.113 / Chapter 3.4.3 --- Effect of Calcium-Inducing Agents on TNF-Treated L929Cells --- p.127 / Chapter 3.5 --- Relationship between Reactive Oxygen Species and Calcium in Tumor Necrosis Factor-Alpha-Mediated Cytotoxicity --- p.133 / Chapter 3.5.1 --- Introduction --- p.133 / Chapter 3.5.2 --- Effect of Intracellular Calcium Chelator on TNF- Mediated ROS Release and Cytotoxicity --- p.133 / Chapter 3.5.3 --- Effect of Mitochondrial Calcium on TNF-Mediated ROS Release and Cytotoxicity --- p.147 / Chapter 3.6 --- Effect of Tumor Necrosis Factor-Alpha on pH --- p.162 / Chapter 3.6.1 --- Introduction --- p.162 / Chapter 3.6.2 --- Effect of TNF on pH --- p.162 / Chapter 3.7 --- Effect of Tumor Necrosis Factor-Alpha on Mitochondrial Membrane Potential --- p.165 / Chapter 3.7.1 --- Introduction --- p.165 / Chapter 3.7.2 --- Effect of TNF and Some Drugs on Mitochondrial Membrane Potential --- p.165 / Chapter 3.8 --- "Comparison of Effects of Tumor Necrosis Factor-Alpha on Susceptible Cell Line, L929 and Resistant Cell Line, rL929, rL929-11E and rL929-4F" --- p.169 / Chapter 3.8.1 --- Introduction --- p.169 / Chapter 3.8.2 --- Effect of TNF on the Cytotoxicity of Resistant Cell Lines --- p.170 / Chapter 3.8.3 --- Effect of TNF on the Release of ROS in Resistant Cell Lines --- p.170 / Chapter 3.8.4 --- Effect of TNF on the Release of Calcium in Resistant Cell Lines --- p.178 / Chapter 3.8.5 --- Effect of TNF on Cell Cycle in Resistant Cell Lines --- p.185 / Chapter Chapter 4. --- General Discussion --- p.187 / Chapter 4.1 --- Tumor Necrosis Factor Induced Apoptosis in L929 Cells --- p.188 / Chapter 4.2 --- Tumor Necrosis Factor Increased the Release of Reactive Oxygen Species in L929 Cells --- p.189 / Chapter 4.3 --- Tumor Necrosis Factor Increased the Release of Calcium in L929 Cells --- p.194 / Chapter 4.4 --- Calcium Induced Reactive Oxygen Species Release in TNF- Treated L929 Cells --- p.197 / Chapter 4.5 --- Tumor Necrosis Factor Did Not Change the pH and Mitochondrial Membrane Potential in TNF-Treated L929 Cells --- p.198 / Chapter 4.6 --- Tumor Necrosis Factor Did Not Increase the Release of Reactive Oxygen Species or Calcium in Resistant Cell Lines --- p.201 / Chapter Chapter 5. --- Future Perspective --- p.204 / Chapter 5.1 --- The Relationship Between Tumor Necrosis Factor and Cytochrome c --- p.205 / Chapter 5.2 --- The Relationship Between Tumor Necrosis Factor and Mitochondrial DNA Damage --- p.206 / Chapter 5.3 --- Clinical studies with Tumor Necrosis Factor --- p.206 / References --- p.208

by Chan Hung Chuen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 143-151). / Abstract also in Chinese. / Acknowledgments --- p.i / Abstract --- p.ii / Abstract (Chinese version) --- p.v / Abbreviations --- p.viii / Content --- p.ix / Chapter CHAPTER ONE --- INTRODUCTION / Chapter 1. --- Free radical and free radical-mediated antitumor drugs --- p.1 / Chapter 2. --- Mitomycin C (MC) / Chapter 2.1 --- Drug actions of MC --- p.2 / Chapter 2.2 --- Adverse side effects of MC --- p.5 / Chapter 3. --- Doxorubicin (DOX) / Chapter 3.1 --- Drug actions of DOX --- p.7 / Chapter 3.2 --- Adverse side effects of DOX --- p.8 / Chapter 4. --- Antioxidants --- p.14 / Chapter 5. --- Effects of exogenous ATP on the antitumor activity of Doxorubicin and Mitomycin C / Chapter 5.1 --- Glutathione (GSH) and related enzymes --- p.17 / Chapter 5.2 --- Glutathione (GSH) and Anticancer Quinones --- p.19 / Chapter 5.3 --- Glutathione and the cardiac toxicity of the anticancer drugs --- p.20 / Chapter 5.4 --- Glutathione depletion in tumor cells by exogenous ATP --- p.21 / Chapter 6. --- Aim of research --- p.24 / Chapter CHAPTER TWO --- THE EFFECT OF ANTIOXIDANTS ON DOXORUBICIN- OR MITOMYCIN C-INDUCED CYTOTOXICITY ON HUMAN TUMOR AND NORMAL CELL LINES / Chapter 2.1 --- Introduction --- p.26 / Chapter 2.2 --- Materials and Methods --- p.28 / Chapter 2.3 --- Results --- p.36 / Chapter 2.4 --- Discussion --- p.60 / Chapter CHAPTER THREE --- STUDY OF CARDIOPROTECTIVE EFFECTS OF ANTIOXIDANTS AGAINST DOXORUBICIN- OR MITOMYCIN C-INDUCED TOXICITY BY LANGENDORFF PERFUEED ISOLATED RAT HEART MODEL / Chapter 3.1 --- Introduction --- p.64 / Chapter 3.2 --- Materials and Methods --- p.67 / Chapter 3.3 --- Results --- p.75 / Chapter 3.4 --- Discussion --- p.76 / Chapter CHAPTER FOUR --- THE EFFECT OF ANTIOXIDANTS DURING CHEMOTHERAPY OF DOXORUBICIN OR MITOMYCIN C IN TUMOR-BEARING MICE / Chapter 4.1 --- Introduction --- p.78 / Chapter 4.2 --- Materials and Methods --- p.80 / Chapter 4.3 --- Results --- p.83 / Chapter 4.4 --- Discussion --- p.93 / Chapter CHAPTER FIVE --- HISTOLOGICAL STUDY AND LIPID PEROXIDATION STUDY OF PROTECTIVE EFFECT OF ANTIOXIDANTS IN TUMOR-BEARING MICE TREATED WITH DOXORUBICIN OR MITOMYCIN C / Chapter 5.1 --- Introduction --- p.95 / Chapter 5.2 --- Materials and Methods --- p.98 / Chapter 5.3 --- Results --- p.103 / Chapter 5.4 --- Discussion --- p.117 / Chapter CHAPTER SIX --- EFFECT OF EXOGENOUS ATP ON THE ANTITUMOR ACTIVITY OF DOXORUBICIN AND MITOMYCIN C ON CULTURED HUMAN HEPATOMA CELLS / Chapter 6.1 --- Introduction --- p.122 / Chapter 6.2 --- Materials and Methods --- p.124 / Chapter 6.3 --- Results --- p.126 / Chapter 6.4 --- Discussion --- p.136 / Chapter CHAPTER SEVEN --- CONCLUSION / Chapter 7.1 --- Conclusion --- p.139 / Chapter 7.2 --- Future perspective --- p.141 / Bibliography --- p.142

The work in this thesis is divided into two parts; the first is the synthesis of a ‘switch-on’ fluorophore to measure cell viability, and the second is the development of a fluorescent detection method for protein−peptide affinity assays applied in the identification of protein-protein inhibitors. Tetrazolium salts are often used in cytotoxicity assays as indicators of cell viability as they are reduced to deeply coloured formazans exclusively in healthy cells. However, measuring the absorbance of the formazan is prone to bias from other coloured species in the cell media, requires solubilisation and can be difficult to quantify. A preferable method of detection is direct fluorescence as it is easily quantified, more sensitive and would ideally remove the need to solubilise the insoluble dye. The aim of this project was to synthesise a tetrazolium salt that could be reduced to a soluble fluorescent formazan in healthy cells as an indicator of cell viability. A number of fluorescent formazans were synthesised by incorporation of a fluorophore. The corresponding tetrazolium salts were non-fluorescent and could be reduced to the formazan in vitro. Several formazans were synthesised to attempt to increase the emission wavelength and intensity to overcome cellular autofluorescence. Protein-protein interactions have been implicated in the pathogenesis of many human diseases but until recently were considered undruggable. However, peptides have emerged as ideal compounds for targeting the large and relatively featureless protein interfaces. Work focussed on the discovery of peptide inhibitors for the E3 ubiquitin ligase stationary-phase kinase associated protein (Skp2). Potential peptide inhibitors were identified using CelluSpot synthesis and array technology to screen peptide libraries. Qualitative analysis of the protein affinity assay results by enhanced chemiluminescent detection was found to be misleading, and so a quantifiable and more sensitive fluorescent detection method was developed.

Compostos de cobre(II) dinucleares, contendo ligantes nitrogenados, foram preparados, caracterizados por diversas técnicas espectroscópicas (UV/Vis, IV e EPR) e tiveram sua reatividade frente a células melanomas (B16F10 e TM1) verificada. Estes compostos são miméticos da tirosinase, enzima contendo em seu sítio ativo dois íons de cobre, presente em bactérias, plantas, animais e humanos, sendo responsável pela oxidação de fenóis a catecóis e destes às correspondentes quinonas. São enzimas relacionadas também à melanogênese, isto é, síntese de melanina, com formação de polímeros eumelanina e feomelanina, responsáveis pela pigmentação de nossa pele, olhos e cabelos. Os compostos mononucleares correspondentes foram também preparados e estudados, para efeito de comparação. Os resultados indicaram que os complexos dinucleares são mais ativos, tanto como miméticos da tirosinase, quanto em relação à citotoxicidade frente a melanomas, que os análogos mononucleares, mostrando que a estrutura é um fator determinante de ambas as atividades biológicas aqui estudadas. Ensaios de interação com as biomoléculas DNA e albumina humana (HSA) através de espectroscopia de UV/Vis e dicroísmo circular (CD) respectivamente, também foram realizados e complementaram os estudos. Atividade nuclease significativa foi observada para os complexos dinucleares, em presença de peróxido de hidrogênio, através de ensaios de clivagem em gel de agarose, buscando uma possível elucidação dos mecanismos de ação dos complexos em estudo. / Dinuclear copper(II) complexes with nitrogenated ligands were prepared, characterized by spectroscopic techniques (UV/Vis, IR and EPR) and had their reactivity verified towards melanoma cells (B16F10 and TM1). These compounds are tyrosinase mimics, an enzyme present in bacteria, fungi, animals and humans, capable of catalyzing the oxidation of phenols to catechols, and catechols to the corresponding quinines, and containing two copper ions in its active site. Tyrosinases are also enzymes related to melanogenesis, assisting the formation of eumelanin and pheomelanin polymers, responsible for the colour of our eyes, skin and hair. The corresponding mononuclear copper(II) complexes were also prepared and comparative studies were performed. The results indicated that the dinuclear species are more reactive than the mononuclear ones, both as tyrosinase mimics as in cytotoxicity damage to melanoma cells, showing that the structure of such species is a determining factor of both biological activities. Experiments at the interactions of these complexes with the biomolecule DNA and human serum albumim, were also conducted by UV/Vis and circular dichroism spectroscopies, respectively, and complemented the previous studies. Nuclease activity was also assessed, in the presence of hydrogen peroxide, monitored by cleavage assays in agarose gel, in order to contribute to the elucidation of the mechanisms of action of these complexes

As 2-acil-cicloexano-1,3-dionas naturais são de ocorrência bastante restrita, sendo relatadas somente em dois gêneros de plantas (Peperomia, Philodendron e Virola) e em insetos das ordens Lepidoptera e Hymenoptera, tendo sido detectadas atividades citotóxica e cairomonal. Foram sintetizados 77 policetídeos da classe das 2-acil-cicloexano-1,3-dionas (36 inéditos) que foram ensaiados quanto à atividade citotóxica em três linhagens de células leucêmicas (K562, Nalm6 e Raji) e também como inibidores da enzima 4-hidroxifenilpiruvato dioxigenase (HPPD), importante alvo para a atividade herbicida. Por meio da análise de relação entre a estrutura e atividade (REA), foi possível determinar os principais requisitos estruturais para as atividades estudadas. A previsão das atividades citotóxicas e de inibição da enzima HPPD das 2-acil-cicloexano-1,3-dionas sintetizadas, foram baseadas em duas metodologias estatísticas (Regressão linear Múltipla (MLR) e Análise Discriminante utilizando mínimos quadrados parciais (PLS-DA)) que foram utilizadas para a construção de modelos quantitativos e qualitativos de previsão. No modelo de regressão linear múltipla (MLR) obteve-se modelos quantitativos que explicam acima de 80% das variâncias das atividades estudadas, com taxas de acertos superiores a 85% na validação externa. Em relação aos modelos de classificação obtidos através do método PLS-DA, foi possível classificar as substâncias como ativas ou inativas, com taxas de acertos superiores a 80% em todos os modelos criados. As características mais importantes para a atividade de inibição da enzima HPPD foi o tamanho da cadeia lateral e a presença do grupo enólico (4a, 5a, 5d e 5e). Para a atividade citotóxica, na série alifática, a cadeia lateral com 9-11 carbonos (4e, 5a e 6a) apresentou melhores índices de inibição e na série aromática as substâncias com a presença de uma insaturação (8a, 11c e 14a) e grupos retiradores no anel aromático (16a, 17c e 19a) foram ativas. / The natural 2-acyl-cyclohexane-1,3-diones have quite restricted occurrence, being reported from only two plant genera (Peperomia, Philodendron and Virola) and from two insects orders, Lepidoptera and Hymenoptera, in which cytotoxic and kairomonal activities were reported. The 77 polyketides of 2-acyl-cyclohexane-1,3-diones type synthesized (36 novel) were tested for cytotoxic activity against three leukemia cells lines (K562, Nalm6 and Raji), and as inhibitors of 4-hydroxyphenyl pyruvate dioxygenase (HPPD) enzyme, an important target for herbicidal activity. The analysis of structure and activity relationship (SAR) revealed the main structural requirements for the activities studied to predict the cytotoxic activity and inhibition of HPPD enzyme of 2-acyl-cyclohexane-1,3-diones. Two statistical methods (Linear Multiple Regression (MLR) and Discriminant Analysis using partial least squares (PLS-DA)) were used for the construction of quantitative and qualitative prediction models. In the multiple linear regression model (MLR), quantitative models explained more than 80% of the variance of the activity, with hit rates higher than 85% in the external validation. In the classification models obtained from the PLS-DA method, the compounds were divided as active or inactive, with hit rates above 80% in all the models generated. The most important characteristics for the inhibition of the activity of the enzyme HPPD were the size of the side chain and the presence of the enolic group (4a, 5a, 5d e 5e). For the cytotoxic activity in the aliphatic series, the side chain with 9-11 carbons (4e, 5a e 6a) showed higher inhibition indices, while for aromatic series conjugation with a double bond (8a, 11c e 14a) and withdrawing groups in the aromatic ring (16a, 17c e 19a) presented higher activity.

Orientador: Luciane Dias de Oliveira / Banca: Luis Felipe das Chagas e Silva de Carvalho / Banca: Jônatas Rafael de Oliveira / Resumo: As plantas medicinais e os fitoterápicos têm sido utilizados como coadjuvantes e alternativos no combate a diversas doenças com crescente frequência, no entanto, na Odontologia seu uso ainda é bastante limitado. Com isso, o objetivo deste estudo é avaliar a ação antimicrobiana dos extratos aquoso e glicólico de própolis verde sobre micro-organismos anaeróbios de interesse odontológico, bem como sua citotoxicidade, a fim de introduzir e incentivar o uso efetivo e sistemático desse fitoterápico em produtos como dentifrícios e enxaguatórios bucais no combate a cáries e doenças periodontais. Os extratos comerciais aquoso e glicólico de própolis foram obtidos das empresas Apis Flora e Mapric, respectivamente. Para avaliação da atividade antimicrobiana foram utilizadas cepas-padrão (ATCC) de Fusobacterium nucleatum, Parvimonas micra, Porphyromonas endodontalis Porphyromonas gingivalis e Prevotella intermedia em cultura planctônica, verificando a concentração inibitória mínima e concentração microbicida mínima (CIM e CMM), segundo Clinical and Laboratory Standards Institute. Para biofilmes monotípicos, suspensões padronizadas (107 céls/mL) foram adicionadas em poços de microplacas e após 48 h em anaerobiose foram tratados com 3 concentrações do extrato de própolis (n=12) por 5 min. Foi incluído um controle positivo (solução fisiológica) e um controle negativo (clorexidina). O biofilme foi mensurado pelos testes MTT e Cristal Violeta. Para análise de citotoxicidade, queratinócitos hu... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Medicinal plants and herbal medicines have been used as adjuvants and alternatives in fighting various diseases with increasing frequency. However, in dentistry its use is still quite limited. Therefore, the objective of this study is to evaluate the antimicrobial action of the aqueous and glycolic extracts of green propolis on anaerobic microorganisms of dental interest, in order to introduce and encourage the effective and systematic use of this herbal medicine in products such as dentifrices and mouthwashes in the fight against tooth decay and periodontal diseases. Aqueous and glycolic commercial extracts of propolis were obtained from Apis Flora and Mapric companies, respectively.To evaluate the antimicrobial activity, standard strains (ATCC) of Fusobacterium nucleatum, Parvimonas micra, Porphyromonas endodontalis, Porphyromonas gingivalis, and Prevotella intermedia in planktonic culture was used, verifying the minimum inhibitory concentration and minimum microbicide concentration (MIC and CMM), according to Clinical and Laboratory Standards Institute. For monotypic biofilms, standardized suspensions (107 cells / mL) was added to microplate wells and after 48 h in anaerobiosis was treated with 3 concentrations of propolis extracts (n = 12) for 5 min. A positive control (saline solution) and a negative control (chlorhexidine) was included. The biofilm was measured by the MTT and Violet Crystal tests. For cytotoxicity analysis, human keratinocytes (HaCaT) were cultured and ... (Complete abstract click electronic access below) / Mestre

Made available in DSpace on 2017-07-24T19:22:12Z (GMT). No. of bitstreams: 1 Lidia Yileng Tay Chu Jon.pdf: 1011394 bytes, checksum: 9cfa95ca6ba9d9c4b6cb8db597101aa8 (MD5) Previous issue date: 2010-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to evaluate the effect of water storage time and of a heat treatment on the cytotoxicity of soft lining denture material using the 3H-thymidine incorporation test. Sample disks (10 mm X 1 mm) of soft lining denture Dentusoft, Dentuflex, Trusoft, Ufi Gel P and of denture base acrylic resin Lucitone 550 were fabricated under aseptic conditions. Twelve specimens of each material were prepared and divided into four groups: GN: The specimens received no treatment or storage in water, G24: The specimens were stored in distilled water at 37°C for 24 hours; G48: The specimens were stored in distilled water at 37°C for 48 hours, GHW: The specimens were immersed in water at 55 °C for 10 minutes. To analyze the cytotoxic effect, three samples of each experimental group were placed in test tubes with 9 ml of DMEM's medium supplemented and incubated at 37 °C for 24 hours. During this incubation period, the toxic substances were broadcast to the culture medium, forming the extracts that were used for the cytotoxicity test. The cytotoxicity of each material was analyzed quantitatively by the incorporation of radioactivity 3H - thymidine by checking the number of viable cells for the synthesis of DNA. The results of DNA synthesis were subjected to analysis of variance in a factorial two-way (material and storage time in water). Comparing the averages of cell viability with the classification of cytotoxic established by ISO 10993-5, it was found that Ufi Gel P had non-cytotoxic effect, Trusoft had slightly cytotoxic effect, Dentuflex had a moderated cytotoxic effect, all in any experimental condition. It was also observed that the Dentusoft alternated between slightly cytotoxic and non-cytotoxic effect because their average viability ranged around 75% and Lucitone 550 had non-cytotoxic effect when stored in water for 48 hours, but the others had around 50% cell viability, the slightly moderated cytotoxic effect. It is concluded that the soft lining denture based in acrylic resin had a slightly and moderated cytotoxic effect, Ufi Gel P, the silicone based soft liner, was not cytotoxic; the effect of water storage after 24 hours or 48 hours and the heat treatment did not reduce the cytotoxicity effect of soft lining denture materials. / O objetivo deste estudo foi avaliar, por meio do teste quantitativo de incorporação de 3H-timidina, a citotoxicidade de materiais reembasadores resilientes em função do tempo de armazenamento em água e em função de um tratamento térmico. Doze corpos-de-prova de cada material reembasador resiliente (Dentusoft, Dentuflex, Trusoft e Ufi Gel P) e da resina termopolimerizável (Lucitone 550) foram confeccionados de forma asséptica em forma de discos e divididos em 4 grupos: GN: os corpos-de-prova não receberam nenhum tipo de tratamento ou armazenamento; G24: os corpos-de-prova foram armazenados em água destilada à 37ºC por 24 horas; G48: os corpos-de-prova foram armazenados em água destilada à 37ºC por 48 horas; GAQ: os corpos-de-prova foram imersos em água a 55°C por 10 minutos. Para a análise do efeito citotóxico, três corpos-de-prova de cada grupo experimental foram colocados dentro de tubos de ensaio com 9 mL de meio de cultura DMEM suplementado e incubados a 37ºC por 24 horas. Durante esse período, as substâncias tóxicas foram difundidas para o meio de cultura, formando os extratos que foram utilizados no teste de citotoxicidade. Esta foi analisada quantitativamente por meio da incorporação do radioisótopo 3H-timidina, verificando o número de células viáveis pela síntese de DNA. Os resultados foram submetidos à análise de variância em esquema fatorial de dois fatores incluindo ainda um grupo controle, ao nível de 5% de significância. Confrontando-se as médias obtidas de viabilidade celular com a classificação do efeito citotóxico estabelecida pela ISO 10993-5, verificou-se que o Ufi Gel P foi considerado não-citotóxico, o Trusoft levemente citotóxico e o Dentuflex discretamente citotóxico, em qualquer condição experimental. Observou-se também que o Dentusoft alternou entre levemente citotóxico e não-citotóxico porque suas médias de viabilidade variaram em torno de 75% e o Lucitone 550 apresentou efeito não-citotóxico quando armazenado em água por 48 horas, mas as outras médias ficaram em torno de 50% de viabilidade celular, entre levemente-citotóxico e discretamente citotóxico. Concluiu-se que os reembasadores resilientes a base de resina acrílica (Trusoft e Dentuflex) foram classificados como levemente citotóxico e discretamente citotóxico, respectivamente. O condicionador de tecido (Dentusoft) alternou entre levemente citotóxico e não citotóxico e o reembasador resiliente a base de silicone (Ufi Gel P) não teve efeito citotóxico. O armazenamento em água ou o tratamento térmico não diminuiu a citotoxicidade dos reembasadores resilientes e o armazenamento em água reduziu a citotoxicidade da resina acrílica para base de prótese (Lucitone 550).

Made available in DSpace on 2017-07-24T19:22:35Z (GMT). No. of bitstreams: 1 STELLA M GLACI REINKE.pdf: 3927224 bytes, checksum: 373236863b3ac97c702e89a859ee8077 (MD5) Previous issue date: 2014-02-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Glass ionomer cement (GIC) is a widely used material in dentistry for providing both adhesion to dental tissues and anticariogenic activity. Previous studies have suggested that the incorporation of antimicrobials to GIC allows an increase in the longevity of restorations as well as an antibacterial activity against biofilm deposited on the restorations. In order to have a better incorporation of an antimicrobial to GIC, this study aims at evaluating a GIC containing chlorhexidine digluconate (Clx Dg)-loaded (meth)acrylic microparticles. In brief, it was carried out a laboratory study (1) to formulate and to evaluate Clx Dg-loaded (meth)acrylic microparticles for being added into a commercial GIC and (2) to investigate the cytotoxic and mechanical properties of this novel material. Microparticles were obtained by the non-aqueous emulsion/solvent evaporation method using Eudragit® S100 and RS100 as polymers and Clx Dg at 10 and 25%. The characterization was performed by morphological, thermal and spectroscopic methods and by evaluating the drug content and drug release. The two best formulations of microparticles were incorporated into a commercial GIC and resulted in two new experimental materials. The pure GIC was used as control. The biocompatibility of these materials was investigated using dental pulp cells and human gingival fibroblasts. In addition, the antimicrobial activity and the mechanical properties (resistance to abrasion, compressive strength, diametral tensile strength and flexural strength) were carried out. Clx Dg-loaded (meth)acrylic microparticles were successfully prepared. Micrometer-sized, heat-stable, and amorphous/non-crystalline formulations with high drug-loading efficiencies, effective antimicrobial activity, and a controlled release of the drug were obtained. The incorporation of Clx Dg-loaded (meth)acrylic microparticles into GIC provided antimicrobial properties to this material and did not increase its cytotoxicity. The mechanical properties demonstrated positive and negative changes after the microparticles incorporation. However these changes did not contraindicate the use of this new material. It was concluded that it was possible to obtain a GIC containing innovative Clx Dg-loaded (meth)acrylic microparticles that showed suitable features and performance. This new material has a promising potential for restorative procedures. However, additional clinical studies are required. / O cimento de ionômero de vidro (CIV) é um material amplamente utilizado na Odontologia, por apresentar capacidade de adesão aos tecidos dentários e atividade anticariogênica. Estudos anteriores têm sugerido que a incorporação de antimicrobianos ao CIV permite um aumento na longevidade das restaurações, assim como uma ação antibacteriana frente ao biofilme dental depositado sobre as restaurações. Com o intuito de otimizar a incorporação do antimicrobiano ao CIV o presente estudo propõe-se a desenvolver, caracterizar e avaliar um CIV contendo micropartículas (met)acrílicas de digluconato de clorexidina (Clx Dg). Realizou-se um estudo laboratorial para (1) formular e avaliar micropartículas (met)acrílicas de Clx Dg para serem adicionadas em um CIV comercial e (2) investigar as propriedades citotóxicas e mecânicas desse novo material. As micropartículas foram obtidas pelo método de emulsão em meio não aquoso/evaporação do solvente a partir dos polímeros (Eudragit® S100 e RS100) e do Clx Dg a 10 e 25%. A caracterização dos materiais microparticulados foi feita por métodos morfológicos, térmicos e espectroscópicos, avaliação do teor e liberação do fármaco. As duas melhores formulações de micropartículas foram incorporadas em um CIV já comercializado, obtendo-se dois materiais experimentais além do CIV puro, considerado como controle. Estes materiais foram submetidos à análise de biocompatibilidade com células de polpa dental e fibroblastos gengivais humanos, a atividade antimicrobiana e a avaliação de propriedades mecânicas (resistência à abrasão, à compressão, à tração diametral e flexão). As micropartículas (met)acrílicas de Clx Dg foram preparadas com sucesso, apresentando características de: partículas de tamanho micrométrico, termoestáveis, amorfas/não-cristalinas, com alta eficiência de encapsulação do fármaco, atividade antimicrobiana comprovada, liberação lenta e controlada do fármaco. A incorporação das micropartículas (met)acrílicas de Clx Dg ao CIV acrescentou capacidade antimicrobiana ao material e não causou aumento da citotoxicidade do mesmo. As propriedades mecânicas sofreram alterações positivas e negativas após a incorporação das micropartículas, porém sem contraindicar o uso desse novo material. Conclui-se que foi possível desenvolver, caracterizar e avaliar o CIV contendo micropartículas (met)acrílicas inovadoras de Clx Dg, e que o mesmo apresentou características e desempenho satisfatórios. Esse novo material tem potencial promissor para procedimentos restauradores, necessitando a realização de estudos clínicos.