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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.
41

Efeito antinociceptivo da crotalfina sobre a dor óssea induzida pelo tumor de Walker 256 em fêmur de ratos. / Antinociceptive effect of crotalphine in bone pain induced by Walker 256 tumor cells into femoral cavity of rats.

Gutierrez, Vanessa Pacciari 09 May 2013 (has links)
Neste estudo padronizamos modelo de dor óssea induzida pela administração de células do tumor de Walker 256 em fêmur de ratos e avaliamos o efeito analgésico da crotalfina, um peptídeo com atividade analgésica. Análises radiográficas, tomográficas e cintilográficas demonstraram a presença de processos osteolíticos difusos, destruição do tecido cortical ósseo e intensa atividade osteogênica. Foi detectado aumento de partes moles adjacentes ao osso, fenômeno observado em pacientes com câncer ósseo. Análises histopatológicas mostraram a presença de células tumorais no pulmão, baço e fígado dos animais, indicando disseminação das células tumorais. Foi detectada a presença de hiperalgesia, alodinia e dor manifesta, a partir do 1º dia após a inoculação das células, persistindo por pelo menos 14 dias. Crotalfina (8 <font face=\"Symbol\">mg/kg, p.o) administrada no 14º dia, bloqueou estes fenômenos. Esse efeito antinociceptivo é de longa duração (48 h) e mediado por receptores opióides do tipo <font face=\"Symbol\">k e <font face=\"Symbol\">d. Não foi observado desenvolvimento de tolerância após o tratamento prolongado com crotalfina. / The aim of the present work was to standardize a new rat model of bone pain induced by the injection of Walker 256 carcinoma cells into the femoral cavity of rats, and to evaluate the analgesic effect of crotalphine, an analgesic peptide. Radiographic, tomographic and scintigraphic analysis showed the presence of diffuse osteolytic processes, destruction of cortical bone tissue and intense osteogenic activity. Increase of soft tissue adjacent to the bone was also detected, being this phenomenon observed in patients with bone cancer. Hystopathological analysis showed the presence of tumor cells in lungs, spleen and liver, indicating the occurrence of metastasis. Tumor cell inoculation induced the presence of hyperalgesia, allodynia and spontaneous pain. Crotalphine (8 <font face=\"Symbol\">mg/kg, p.o.), administered on day 14, blocked these phenomena. This antinociceptive effect is long-lasting effect (2 days) and mediated by peripheral <font face=\"Symbol\">k and <font face=\"Symbol\">d- opioid receptors. Prolonged treatment with crotalphine (14 days) did not cause the development of tolerance to its antinociceptive effect.
42

Avaliação do efeito antitumoral do gadolínio

Izabela Galvão 13 April 2011 (has links)
Espécies reativas de oxigênio (ROS) são geradas como produto final da respiração mitocondrial. Quando ROS são produzidas em excesso geram estresse oxidativo e induzem citotoxicidade via uma variedade de mecanismos, incluindo dano ao DNA, lipídeos e proteínas. Neste trabalho avaliamos a capacidade do lantanídeo gadolínio em produzir estresse oxidativo com a finalidade de aproveitar o potencial citotóxico de ROS para o tratamento de tumores. Utilizamos dois modelos experimentais: o primeiro modelo utilizado foi duas linhagens de glioblastoma humano, T98 status p53 mutante e U87 status p53 selvagem para avaliar a citotoxicidade do gadolínio sobre o metabolismo celular e também alterações morfológicas, nucleares e produção de ROS. O segundo modelo utilizado foi 8 linhagens da levedura Saccharomyces cerevisae, selvagem e mutantes relacionadas ao estresse oxidativo, para avaliar o efeito do gadolínio e para obter informações sobre seu possível mecanismo de ação. Os resultados mostram que o gadolínio foi capaz de induzir citotoxicidade e diminuir a viabilidade celular em ambas as linhagens de glioblastoma humano, além de provocar alterações nucleares e produzir ROS. A adição de radiação (Gd159) aumentou todos os efeitos citotóxicos provocados pelo gadolínio. Ambas as linhagens obtiveram mesmas respostas frente ao gadolínio sugerindo que as alterações observadas foram independentes de p53. Na levedura Saccharomyces cerevisiae o gadolínio foi capaz de inibir o crescimento celular, sendo a mutante &#916;sod1 a mais sensível. As leveduras foram capazes de incorporar gadolínio de maneira dose-dependente. A mutante &#916;sod1 incorporou mais gadolínio quando comparado à linhagem selvagem. As células testadas não possuem receptores específicos de interação com este metal na membrana celular. Ao incorporar gadolínio existe uma extrusão de potássio da célula. A presença de gadolínio não foi capaz de induzir peroxidação de lipídeos, ao contrário, diminuiu a quantidade de lipídeos peroxidados. Este metal foi capaz de diminuir, significantemente, a quantidade de grupamentos tióis livres, indicando um possível alvo em proteínas do sistema de controle redox celular. A presença deste metal aumentou a geração de ROS, apresentando maior intensidade nas mutantes &#916;skn7, &#916;sod2 e &#916;cta1. Além disso, provocou a diminuição da viabilidade celular. Todos estes achados levam a concluir que o gadolínio pode ser um metal de escolha para o desenvolvimento de novas drogas para o tratamento de câncer. / Reactive oxygen species (ROS) are generated as end products of mitochondrial respiration. When ROS are produced in excess generates oxidative stress and induce cytotoxicity via a variety of mechanisms, including damage to DNA, lipids and proteins. In this work we evaluate the ability of the lanthanide gadolinium in producing oxidative stress in order to used the cytotoxic potential of ROS to the treatment of tumors. We used two experimental models: the first model used was two strains of human glioblastoma, T98 status p53 mutant and U87 status p53 wild type to evaluate the cytotoxicity of gadolinium on cell metabolism and also morphological changes, nuclear and ROS production. The second model was used eight strains of the yeast Saccharomyces cerevisiae, wild type and mutant related to oxidative stress, to assess the effect of gadolinium and for obtains same information about the possible mechanism of action. The results show that gadolinium was able to induce cytotoxicity and decrease cell viability of both strains of human glioblastoma, and cause nuclear changes and produce ROS in a dose dependent way. The addition of radiation (Gd159) increased all cytotoxic effects caused by gadolinium. Both of strains had the same response to gadolinium suggesting that the observed changes were independent of p53. In the yeast Saccharomyces cerevisiae gadolinium was able to inhibit cell growth, and the mutant &#916;sod1 was the most sensitive. The yeasts were able to incorporate gadolinium in a dose-dependent way. The mutant &#916;sod1 incorporate more gadolinium compared to the wild type. The cells tested do not have specific receptors for interaction with this metal in the cell membrane. By incorporating gadolinium there is an extrusion of potassium from the cell. The presence of gadolinium was not able to induce lipid peroxidation, in contrast, decreased the amount of lipid peroxidate. This metal was able to decrease significantly the amount of free thiol groups, indicating a possible target protein in the cellular redox control system. The presence of this metal increased the generation of ROS, with higher intensity in the mutant &#916;skn7, &#916;sod2 and &#916;cta1. In addition, Gd produced significant decreased on cell viability. All these findings led us to conclude that gadolinium may be a metal of choice for developing new drugs for cancer treatment.
43

Avaliação do papel dos miRNAs -221, -222 e -4728-3p em células-tronco tumorais derivadas de linhagens celulares de cancer de mama HER2+. / Evaluation of the role of miRNAs -221, -222 e -4728-3p in breast cancer stem cells derived from HER2+ cell lines.

Carneiro, Juliana Laino do Val 09 August 2013 (has links)
CSCs, caracterizadas pela alta atividade da ALDH1 e expressão (ou não) de marcadores de células-tronco embrionárias OCT-4, NANOG, SOX2, KLF4, LIN2, estão presentes em tumores de mama HER2+. Mamosferas são estruturas celulares esferóides in vitro enriquecidas em CSCs. Neste trabalho, buscou-se um melhor entendimento do papel dos miRNAs -221, -222 e -4728-3p na biologia das CSCs. Foi observado alto percentual de células ALDH1+ (citometria) em mamosferas das linhagens MCF-7, SKBR3 e BT-474; alta expressão (qRT-PCR) de miR-221 e -222 em mamosferas da linhagem MCF-7 e de tumores de pacientes, além de alta expressão de HER2 em mamosferas das linhagens MCF-7 e SKBR3. A MFE de células MCF-7 mostrou-se aumentada após a indução (com lentivetores) da superexpressão dos miRNAs -221 e -222. A resistência ao quimioterápico paclitaxel estava aumentada em mamosferas que superexpressavam o miRNA-222. A superexpressão de miR-4728-3p, localizado em um intron de HER2, levou a um aumento das subpopulações ALDH1+ em duas linhagens celulares reforçando seu envolvimento com a biologia de CSCs. / CSCs, characterized by high activity of ALDH1 and high (or not) expression of embryonic stem cell markers OCT-4, NANOG, SOX2, KLF4, LIN28 are present in tumors with HER2 amplification. Mammospheres are spheroid cell structures in vitro enriched by CSCs. In this study, we aim to contribute to the better understanding the role of miRNAs -221, 222, 4728-3p in the the biology of CSCs. We observed high percentage of ALDH+ cells (cytometry) in mammospheres of MCF-7, SKBR3 and BT-474 cell lines; high expression (qRT-PCR) of miR-221 and -222 in mammospheres of MCF-7 cell line and cells derived from patients, moreover HER2 is upregulated in mammospheres from MCF-7 and SKBR3 cell lines. MFE is higher in MCF-7 cell line after induction (with lentivectors) of miR-221 and -222 expression. The resistance to paclitaxel was increased in mammopheres that were overexpressing miRNA-222. Overexpression of miR-4728-3p, located in an intron of HER2 gene, induced the increment of ALDH1+ subpopulations in two cell lines, reinforcing its role in the biology of CSCs.
44

Effects of tumor necrosis factor on taurine transport in cultured rat astrocytes.

January 1993 (has links)
by Chang Chuen Chung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 125-140). / Acknowledgement --- p.4 / List of Abbreviations --- p.5 / Abstract --- p.7 / Chapter CHAPTER I --- INTRODUCTION --- p.10 / Chapter 1.1 --- Astrocytes in the Central Nervous System --- p.10 / Chapter 1.1.1 --- Characteristics of astrocytes --- p.10 / Chapter 1.1.2 --- Functional roles of astrocytes --- p.11 / Chapter 1.1.2.1 --- General functions of astrocytes --- p.11 / Chapter 1.1.2.2 --- Volume regulation of astrocytes in CNS injuries --- p.12 / Chapter 1.1.2.3 --- Immunological functions of astrocytes --- p.13 / Chapter 1.2 --- Taurine in the CNS --- p.15 / Chapter 1.2.1 --- The biochemistry and distribution of taurine --- p.15 / Chapter 1.2.2 --- Physiological functions of taurine in the CNS --- p.19 / Chapter 1.2.3 --- Uptake and release of taurine by cultured astrocytes --- p.20 / Chapter 1.2.3.1 --- Taurine uptake in astrocytes --- p.21 / Chapter 1.2.3.2 --- Taurine release in astrocytes --- p.22 / Chapter 1.3 --- Tumor necrosis factor in the CNS --- p.23 / Chapter 1.3.1 --- Characteristics of tumor necrosis factor --- p.23 / Chapter 1.3.2 --- Sources of TNF in the CNS --- p.25 / Chapter 1.3.3 --- Functions of TNF in the CNS --- p.26 / Chapter 1.3.4 --- TNF and signal transduction --- p.27 / Chapter 1.4 --- cGMP second messenger system in astrocyte --- p.29 / Chapter 1.4.1 --- cGMP as second messenger in astrocytes --- p.29 / Chapter 1.4.2 --- Post cGMP cascade effects --- p.30 / Chapter 1.5 --- The aims of this project --- p.30 / Chapter CHAPTER II --- METHODS --- p.34 / Chapter 2.1 --- Primary astrocytes culture --- p.34 / Chapter 2.1.1 --- Primary rat astrocytes culture --- p.34 / Chapter 2.1.2 --- Primary mouse astrocytes culture --- p.36 / Chapter 2.1.3 --- Culture of rat C6 glioma cell line --- p.36 / Chapter 2.1.4 --- Subculture of astrocytes in different media --- p.37 / Chapter 2.2 --- Taurine uptake and release assay --- p.39 / Chapter 2.2.1 --- Taurine uptake assay --- p.39 / Chapter 2.2.2 --- Taurine release assay --- p.41 / Chapter 2.3 --- The effects of TNF on taurine transport --- p.42 / Chapter 2.4 --- The effects of TNF on cell volume in astrocytes --- p.43 / Chapter 2.5 --- "The effects of TNF on amino acids, glucose and neurotransmitters uptake" --- p.43 / Chapter 2.5.1 --- The effects of TNF on amino acids uptake --- p.43 / Chapter 2.5.2 --- The effects of TNF on glucose uptake --- p.44 / Chapter 2.5.3 --- The effects of TNF on neurotransmitters uptake --- p.45 / Chapter 2.6 --- The effects of LPS on taurine uptake in astrocytes --- p.46 / Chapter 2.7 --- The effects of IFN-¡’ on taurine uptake in astrocytes --- p.46 / Chapter 2.8 --- The effects of PMA on taurine uptake in astrocytes --- p.47 / Chapter 2.9 --- "The effects of TNF on thymidine, uridine and leucine incorporation in astrocytes" --- p.47 / Chapter 2.10 --- The effects of TNF on basal level of cGMP in astrocytes --- p.48 / Chapter 2.11 --- The effects of TNF on protein phosphorylation in astrocytes --- p.49 / Chapter 2.12 --- The effects of TNF on calcium uptake in astrocytes --- p.50 / Chapter CHAPTER III --- RESULTS --- p.51 / Chapter 3.1 --- The effects of TNF on taurine transport in cultured rat astrocytes --- p.51 / Chapter 3.1.1 --- The effects of TNF on [3H]-taurine uptake -time course study --- p.52 / Chapter 3.1.2 --- The effects of TNF on the kinetic parameters of the taurine uptake system --- p.54 / Chapter 3.1.3 --- The effects of TNF concentration on taurine uptake --- p.63 / Chapter 3.1.4 --- The effects of TNF exposure time on taurine uptake --- p.65 / Chapter 3.1.5 --- The effects of TNF on cell volume change in astrocytes --- p.67 / Chapter 3.1.6 --- "Comparison of the effects of TNF on taurine uptake amongst cultured primary rat astrocytes, primary mouse astrocytes and C6 glioma cell line" --- p.69 / Chapter 3.1.7 --- The effects of TNF on taurine release --- p.71 / Chapter 3.1.8 --- The specificity of the effects of TNF on taurine uptake --- p.74 / Chapter 3.1.8.1 --- The effects of TNF on the uptake of amino acids and glucose in primary rat astrocytes --- p.79 / Chapter 3.1.8.2 --- The effects of TNF on neurotransmitters uptake --- p.87 / Chapter 3.1.9 --- The effects of LPS on taurine uptake in astrocytes --- p.92 / Chapter 3.1.10 --- The effects of IFN-¡’ on taurine uptake in astrocytes --- p.97 / Chapter 3.1.11 --- The effects of PMA on taurine uptake --- p.99 / Chapter 3.2 --- The effects of TNF on cell metabolism in rat astrocytes --- p.102 / Chapter 3.2.1 --- The effects of TNF on astrocyte proliferation --- p.102 / Chapter 3.2.2 --- The effects of TNF on RNA synthesis --- p.103 / Chapter 3.2.3 --- The effects of TNF on protein synthesis --- p.106 / Chapter 3.2.4 --- The effects of TNF on basal level of cGMP --- p.108 / Chapter 3.2.5 --- The effects of TNF on protein phosphorylation --- p.111 / Chapter 3.2.6 --- The effects of TNF on calcium uptake --- p.113 / Chapter Chapter IV --- DISCUSSION AND CONCLUSION --- p.116 / References --- p.125
45

Actions of pineal indoleamines on tumor cell lines and the murine immune system.

January 1994 (has links)
by Poon Yam Kau. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 174-183). / Abstract --- p.1 / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Discovery of melatonin --- p.4 / Chapter 1.2 --- Biosynthesis of melatonin --- p.4 / Chapter 1.3 --- Physiology of melatonin and other pineal indoles --- p.5 / Chapter 1.4 --- Relationship between pineal indoles and cancers --- p.6 / Chapter 1.5 --- Macrophages --- p.9 / Chapter 1.6 --- Lymphocytes --- p.11 / Chapter Chapter 2 --- Effects of different light/dark cycles on serum melatonin level in mice and effect of melatonin-feeding on serum glutamate-oxaloacetate transaminase (GOT) activity in mice / Chapter 2.1 --- Introduction --- p.14 / Chapter 2.2 --- Materials and methods --- p.15 / Chapter 2.3 --- Results --- p.22 / Chapter 2.4 --- Discussion --- p.23 / Chapter Chapter 3 --- Actions of endogenous and exogenous melatonin on murine peritoneal macrophages / Chapter 3.1 --- Introduction --- p.27 / Chapter 3.2 --- Materials and methods --- p.28 / Chapter 3.3 --- Results --- p.33 / Chapter 3.4 --- Discussion --- p.36 / Chapter Chapter 4 --- Actions of endogenous and exogenous melatonin on murine splenic lymphocytes / Chapter 4.1 --- Introduction --- p.55 / Chapter 4.2 --- Materials and methods --- p.56 / Chapter 4.3 --- Results --- p.62 / Chapter 4.4 --- Discussion --- p.69 / Chapter Chapter 5 --- In vitro effects of melatonin on murine peritoneal macrophages and splenic lymphocytes / Chapter 5.1 --- Introduction --- p.105 / Chapter 5.2 --- Materials and methods --- p.106 / Chapter 5.3 --- Results --- p.109 / Chapter 5.4 --- Discussion --- p.113 / Chapter Chapter 6 --- Effects of methoxytryptamine on murine peritoneal macrophages and splenic lymphocytes / Chapter 6.1 --- Introduction --- p.125 / Chapter 6.2 --- Materials and methods --- p.126 / Chapter 6.3 --- Results --- p.129 / Chapter 6.4 --- Discussion --- p.132 / Chapter Chapter 7 --- In vitro effects of pineal indoles on cultured tumor cell lines / Chapter 7.1 --- Introduction --- p.145 / Chapter 7.2 --- Materials and methods --- p.146 / Chapter 7.3 --- Results --- p.148 / Chapter 7.4 --- Discussion --- p.152 / Chapter Chapter 8 --- General Discussion --- p.170 / References --- p.174
46

Effect of combined treatment of tumor necrosis factor-alpha and hyperthermia on human and murine tumor cells.

January 1998 (has links)
by Lam Kai Yi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 156-165). / Abstract also in Chinese. / Chapter Chapter One: --- Introduction --- p.1 / Chapter 1.1 --- Tumor Necrosis Factor-α in Cancer Treatment --- p.1 / Chapter 1.1.1 --- Historical Background --- p.1 / Chapter 1.1.2 --- Mechanisms of Action --- p.2 / Chapter 1.1.2.1 --- Production of Reactive oxidative Species / Chapter 1.1.2.2 --- Increase of Intracellular Free Calcium Concentration / Chapter 1.1.2.3 --- Activation of Ca2+/Mg2+-dependent Endonuclease / Chapter 1.1.2.4 --- Decrease of glucose uptake and Protein Synthesis / Chapter 1.1.2.5 --- Formation of Ion-permeable Channel / Chapter 1.1.2.6 --- Activation of Phospholipase / Chapter 1.1.2.7 --- Increase of S-phase Cells / Chapter 1.1.2.8 --- Immunomodulatory Effects / Chapter 1.1.3 --- Resistance of Cells to TNF-α --- p.7 / Chapter 1.1.4 --- Clinical Studies --- p.11 / Chapter 1.1.5 --- Side Effects --- p.12 / Chapter 1.2 --- Hyperthermia and Cancer Treatment --- p.14 / Chapter 1.2.1 --- Hyperthermic Agents --- p.15 / Chapter 1.2.2 --- Intrinsic Heat Sensitivity --- p.15 / Chapter 1.2.3 --- Mechanisms of Action --- p.17 / Chapter 1.2.3.1 --- Depolarization of Membrane Potential / Chapter 1.2.3.2 --- "Reduction of glucose transport and DNA, mRNA and Protein Synthesis" / Chapter 1.2.3.3 --- Decrease of Intracellular pH / Chapter 1.2.3.4 --- Calcium Imbalance / Chapter 1.2.3.5 --- Effect on Nucleolar Protein / Chapter 1.2.3.6 --- Apoptosis / Chapter 1.2.3.7 --- Induction of Autologous Tumor Killing / Chapter 1.2.3.8 --- "Blood Flow, Tumor Oxygenation and Vascular Damage" / Chapter 1.2.4 --- Clinical Studies --- p.20 / Chapter 1.3 --- Combined Treatment --- p.21 / Chapter 1.3.1 --- Combined Treatment with TNF-α and Fixed-temperature Hyperthermia --- p.22 / Chapter 1.3.2 --- Combined Treatment with TNF + Step-down Hyperthermia --- p.22 / Chapter 1.3.3 --- In Vivo Study --- p.23 / Chapter 1.3.4 --- Sequence of Treatment --- p.24 / Chapter 1.3.5 --- Proposed Mechanism of Synergism --- p.24 / Chapter 1.4 --- Objective of Study --- p.26 / Chapter 1.4.1 --- Sequence of Treatments --- p.26 / Chapter 1.4.2 --- Comparison of Treatments' Effectiveness --- p.27 / Chapter 1.4.3 --- Effect on Normal Cell --- p.27 / Chapter 1.4.4 --- Effect on Distribution of Cells in Cell Cycle Phases --- p.28 / Chapter 1.4.5 --- In Vivo Study --- p.28 / Chapter Chapter Two: --- Materials and Methods --- p.30 / Chapter 2.1. --- Materials --- p.30 / Chapter 2.1.1 --- For Cell Culture --- p.30 / Chapter 2.1.2 --- In vitro Treatments --- p.31 / Chapter 2.1.3 --- DNA Electrophoresis --- p.31 / Chapter 2.1.4 --- Flow Cytometry --- p.32 / Chapter 2.2. --- Reagent Preparation --- p.33 / Chapter 2.2.1 --- Culture Media --- p.33 / Chapter 2.2.2 --- Human Recombinant Tumor Necrosis Factor alpha (rhTNF-α) --- p.33 / Chapter 2.2.3 --- Phosphate Buffered Saline (PBS) --- p.33 / Chapter 2.2.4 --- Lysis Buffer --- p.34 / Chapter 2.2.5 --- TE Buffer --- p.34 / Chapter 2.2.6 --- Proteinase K and Ribonuclease A (RNase A) --- p.34 / Chapter 2.2.7 --- 100 Base-Pair DNA Marker --- p.34 / Chapter 2.2.8 --- Propidium Iodide (PI) --- p.35 / Chapter 2.3 --- Methods --- p.35 / Chapter 2.3.1 --- Cell Culture --- p.35 / Chapter 2.3.1.1 --- Ehrlich Ascitic Tumor (EAT) and Human Leukemia (HL-60) / Chapter 2.3.1.2 --- Human Coronary Artery Endothelial Cells (HCAEC) / Chapter 2.3.2 --- In vitro Experiments --- p.36 / Chapter 2.3.3 --- Tumor Necrosis Factor Treatment --- p.37 / Chapter 2.3.4 --- Hyperthermia Treatments --- p.37 / Chapter 2.3.5 --- Cell Counting --- p.38 / Chapter 2.3.5.1 --- Trypan Blue Exclusion Assay / Chapter 2.3.5.2 --- Neutral Red Assay / Chapter 2.3.6 --- Determination of Additive or Synergistic Effect --- p.39 / Chapter 2.3.7 --- DNA Electrophoresis --- p.40 / Chapter 2.3.8 --- Flow Cytometry --- p.42 / Chapter 2.3.7.1 --- Preparation of Samples / Chapter 2.3.7.2 --- Flow Cytometry Acquisition / Chapter 2.3.7.3 --- Analysis / Chapter 2.3.9 --- In vivo Experiments --- p.44 / Chapter 2.3.8.1 --- Animal Strain / Chapter 2.3.8.2 --- Cell Line / Chapter 2.3.8.3 --- Tumor Necrosis Factor Treatment / Chapter 2.3.8.4 --- Hyperthermia Treatments / Chapter 2.3.8.5 --- Test of Body Temperature / Chapter 2.3.8.6 --- Cell Harvesting / Chapter Chapter Three: --- Result --- p.50 / Chapter 3.1 --- Optimal Sequence of Treatments --- p.50 / Chapter 3.1.1 --- Optimal Sequence of Treatments on Murine Ehrlich Ascitic Tumor (EAT) cells --- p.50 / Chapter 3.1.1.1 --- TNF + Fixed-temperature Hyperthermia / Chapter 3.1.1.2 --- TNF + Step-down Hyperthermia2 / Chapter 3.1.1.3 --- TNF + Step-down Hyperthermia3 / Chapter 3.1.2 --- Optimal Sequence of Treatments on Human Leukemia cells HL-60 --- p.60 / Chapter 3.1.2.1 --- TNF + Fixed-temperature Hyperthermia / Chapter 3.1.2.2 --- TNF + Step-Down Hyperthermia2 / Chapter 3.1.2.3 --- TNF + Step-Down Hyperthermia3 / Chapter 3.2 --- Comparison of Effectiveness of Treatments --- p.72 / Chapter 3.2.1 --- Effectiveness of Various treatments on EAT cells --- p.72 / Chapter 3.2.2 --- Synergistic Effect between rhTNF-α and Hyperthermia on EAT cells --- p.74 / Chapter 3.2.3 --- Decrease of Relative Growth and Viability of EAT with Time --- p.79 / Chapter 3.2.3.1 --- TNF + Fixed-temperature Hyperthermia / Chapter 3.2.3.2 --- TNF + Step-down Hyperthermia2 / Chapter 3.2.3.3 --- TNF + Step-down Hyperthermia3 / Chapter 3.2.4 --- Comparison of Effectiveness of Various Treatments on HL-60 cells --- p.82 / Chapter 3.2.5 --- Synergistic Effect between rhTNF-α and Hyperthermia on HL-60 cells --- p.87 / Chapter 3.2.6 --- Change of Relative Growth and Viability of HL-60 with Time --- p.90 / Chapter 3.2.6.1 --- TNF + Fixed-temperature Hyperthermia / Chapter 3.2.6.2 --- TNF + Step-down Hyperthermia2 / Chapter 3.2.6.3 --- TNF + Step-down hyperthermia3 / Chapter 3.3 --- Cell Death Pathway --- p.96 / Chapter 3.3.1 --- Experiments on Ehrlich Ascitic Tumor (EAT) Cells --- p.96 / Chapter 3.3.2 --- Experiments on Human Leukemia (HL-60) Cells --- p.100 / Chapter 3.4 --- Experiment on Normal Cell --- p.104 / Chapter 3.5 --- Effect of TNF + Fixed-temperature Hyperthermia on the Cell Cycle Progression --- p.107 / Chapter 3.5.1 --- Different Times of TNF Administration and Distribution of EAT cells in Cell cycle --- p.107 / Chapter 3.5.2 --- Different Times of TNF Administration and Distribution of HL-60 cells in Cell Cycle --- p.114 / Chapter 3.5.3 --- Shift of Cells Cycle after TNF Treatment --- p.120 / Chapter 3.5.3.1 --- Response of Ehrlich Ascitic Tumor Cells / Chapter 3.5.3.2 --- Response of Human leukemia Cells / Chapter 3.6 --- Effectiveness of Treatments in vivo: --- p.129 / Chapter 3.6.1 --- Dose-dependent Response --- p.129 / Chapter 3.6.2 --- Change of Body Temperature During Hyperthermia --- p.131 / Chapter 3.6.3 --- Comparison of Effectiveness of Various Treatments in vivo --- p.133 / Chapter 3.6.4 --- Synergistic Effect Between rhTNF-α and Hyperthermia in vivo --- p.135 / Chapter Chapter Four: --- Discussion --- p.138 / Chapter 4.1 --- Optimal Sequence of Treatments --- p.139 / Chapter 4.2 --- Comparison of Various Treatments --- p.143 / Chapter 4.3 --- Distribution of Cells in Cell Cycle Phases --- p.149 / Chapter 4.4 --- In vivo Study --- p.153 / Chapter Chapter Five: --- References --- p.156
47

Modification of anticancer drug sensitivity of human prostate cancer cells by estrogen related compounds.

January 1998 (has links)
by Cheung Tak Chi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 117-123). / Abstract also in Chinese. / Acknowledgeements --- p.i / Abbreviations --- p.ii / Abstract --- p.v / List of Figures --- p.viii / List of Tables --- p.xiv / Contents --- p.xv / Contents / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Epidemiological Risk Factors --- p.1 / Chapter 1.1.1 --- Age --- p.1 / Chapter 1.1.2 --- Race --- p.2 / Chapter 1.1.3 --- Environmental or Migratory Factor --- p.2 / Chapter 1.1.4 --- Diet --- p.2 / Chapter 1.1.5 --- Genetics --- p.3 / Chapter 1.2 --- Regulation of Normal Prostate Development and Function --- p.4 / Chapter 1.3 --- Biochemistry and Development of Prostate Cancer --- p.6 / Chapter 1.3.1 --- Androgen-Dependent Prostate Cancer --- p.6 / Chapter 1.3.2 --- Androgen-Independent Prostate Cancer --- p.8 / Chapter 1.4 --- Classification of Prostate Cancer --- p.9 / Chapter 1.4.1 --- Stage A Prostate Cancer --- p.10 / Chapter 1.4.2 --- Stage B Prostate Cancer --- p.10 / Chapter 1.4.3 --- Stage C Prostate Cancer --- p.11 / Chapter 1.4.4 --- Stage D Prostate Cancer --- p.11 / Chapter 1.5 --- Methods for Early Detection of Prostate Cancer --- p.12 / Chapter 1.6 --- Clinical Treatment of Prostate Cancer --- p.12 / Chapter 1.6.1 --- Surgery --- p.12 / Chapter 1.6.2 --- Radiotherapy --- p.13 / Chapter 1.6.3 --- Chemotherapy --- p.13 / Chapter 1.6.4 --- Hormonal Therapy --- p.13 / Chapter 1.7 --- Objective --- p.14 / Chapter 1.8 --- Estrogen and Its Related Compounds --- p.16 / Chapter 1.8.1 --- 17β-Estradiol --- p.16 / Chapter 1.8.2 --- Tamoxifen --- p.18 / Chapter 1.8.3 --- Aromatase Inhibitor --- p.20 / Chapter 1.9 --- Anticancer Drugs --- p.23 / Chapter 1.9.1 --- Doxorubicin --- p.23 / Chapter 1.9.2 --- cis-Platinum --- p.24 / Chapter 1.10 --- Apoptotic Pathways --- p.25 / Chapter 1.10.1 --- BCL-2 /BAD Pathway --- p.26 / Chapter 1.10.2 --- FADD Pathway --- p.27 / Chapter 1.10.3 --- CAS Pathway --- p.27 / Chapter 2. --- Materials and Methods --- p.28 / Chapter 2.1 --- Materials --- p.28 / Chapter 2.2 --- Cell Lines --- p.32 / Chapter 2.3 --- Preparation of Drugs --- p.32 / Chapter 2.4 --- Drug Sensitivity Assay --- p.33 / Chapter 2.5 --- Cell Cycle Analysis --- p.35 / Chapter 2.6 --- DNA Fragmentation Assay --- p.36 / Chapter 2.7 --- Annexin Binding Assay --- p.37 / Chapter 2.8 --- Western Blot Analysis --- p.38 / Chapter 2.9 --- Data Analysis --- p.41 / Chapter 3. --- Results --- p.42 / Chapter 3.1 --- Response of Human Androgen-Independent Prostate Cancer Cells to Doxorubicin and cis-Platinum --- p.42 / Chapter 3.2 --- The Effect of 17p-Estradiol on the Growth and Anticancer Drug Sensitivity of Human Androgen-Independent Prostate Cancer Cells --- p.45 / Chapter 3.2.1 --- 17β-Estradiol on Cell Growth --- p.45 / Chapter 3.2.2 --- 17β-Estradiol on Anticancer Drug Sensitivity --- p.45 / Chapter 3.2.3 --- 17β-Estradiol and Doxorubicin on Cell Cycle Progression --- p.51 / Chapter 3.2.4 --- 17β-Estradiol and Doxorubicin Induced DNA Fragmentation --- p.57 / Chapter 3.2.5 --- 17β-Estradiol and Doxorubicin on Annexin Staining --- p.59 / Chapter 3.2.6 --- 17β-Estradiol and Doxorubicin on Apoptotic Protein Expression --- p.62 / Chapter 3.3 --- The Effect of Tamoxifen on the Growth and Anticancer Drug Sensitivity of Human Androgen-Independent Prostate Cancer Cells --- p.64 / Chapter 3.3.1 --- Tamoxifen on Cell Growth of Human --- p.65 / Chapter 3.3.2 --- Tamoxifen on Anticancer Drug Sensitivity --- p.65 / Chapter 3.3.3 --- Tamoxifen and Doxorubicin on Cell Cycle Progression --- p.71 / Chapter 3.3.4 --- Tamoxifen and Doxorubicin Induced DNA Fragmentation --- p.76 / Chapter 3.3.5 --- Tamoxifen and Doxorubicin on Annexin Staining --- p.78 / Chapter 3.3.6 --- Tamoxifen and Doxorubicin on Apoptotic Protein Expression --- p.79 / Chapter 3.4 --- The Effect of Aromatase Inhibtiors on the Growth and Anticancer Drug Sensitivity of Human Androgen-Independent Prostate Cancer Cells --- p.81 / Chapter 3.4.1 --- Aromatase Inhibitors on Cell Growth --- p.81 / Chapter 3.4.2 --- Aromatase Inhibitors on Anticancer Drug Sensitivity --- p.83 / Chapter 3.4.3 --- 4-AcA and Doxorubicin on Cell Cycle Progression --- p.93 / Chapter 3.4.4 --- 4-AcA and Doxorubicin Induced DNA Fragmentation --- p.99 / Chapter 3.4.5 --- 4-AcA and Doxorubicin on Annexin Staining --- p.100 / Chapter 3.4.6 --- 4-AcA and Doxorubicin on Apoptotic Protein Expression --- p.102 / Chapter 4. --- Discussion --- p.105 / Chapter 4.1 --- 17 β-Estradiol and Anticancer Drug Sensitivity --- p.106 / Chapter 4.2 --- Tamoxifen and Anticancer Drug Sensitivity --- p.109 / Chapter 4.3 --- Aromatase Inhibitors and Anticancer Drug Sensitivity --- p.112 / Chapter 4.4 --- DU145 Cells vs PC3 Cells --- p.115 / Chapter 5. --- Conclusion and Perspectives --- p.116 / Chapter 6. --- References --- p.117
48

Papel da fucana sulfatada FucSulf I na interação entre células tumorais e o endotélio in vitro / Role of sulfated fucan fucsulfi in tumor-endothelium interactions in vitro

Viviane Wallerstein Mignone Dantas 28 February 2012 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Para formar metástases, as células tumorais devem se desprender do tumor primário e migrar através do endotélio num processo denominado intravasamento. Uma vez na circulação, elas devem aderir ao endotélio do tecido alvo e extravasar para o novo sítio de colonização, onde irão proliferar. A interação das células tumorais com o endotélio é mediada por selectinas, seguida pela interação com integrinas. As células tumorais apresentam um padrão anormal de glicosilação, expressando ligantes de selectinas, formados por polissacarídeos fucosilados, como sialyl Lewis a/x. Durante o processo metastático, células tumorais secretam diversos fatores de crescimento. Além de modular diferentes tipos celulares que constituem o microambiente tumoral, estes fatores de crescimento também atuam nas células tumorais de forma autócrina, ativando vias de sinalização envolvidas na proliferação e migração celular. Polissacarídeos sulfatados como a heparina, podem atuar como inibidores de P e L-selectinas, além de se ligar a fatores de crescimento, impedindo a ativação de seus receptores. Neste trabalho, avaliamos o papel de fucanas sulfatadas extraídas de diferentes espécies de invertebrados marinhos (L. variegatus, S. franciscanus, S. pallidus, A. lixula e S. droebachiensis) na modulação da interação entre células tumorais com o endotélio in vitro e comparamos seu efeito com o da heparina. Também avaliamos o papel destas moléculas na proliferação de células tumorais. Para isso, utilizamos duas linhagens tumorais de próstata (DU-145 e PC-3) e culturas primárias de células endoteliais de veia umbilical humana (HUVECs). Ao avaliar o efeito das fucanas na adesão das células tumorais às HUVECs, observamos que todas as fucanas testadas inibiram a adesão da linhagem DU-145 à monocamada endotelial, enquanto apenas a fucana extraída da espécie L. variegatus (FucSulf I) e da espécie S. franciscanus inibiram a adesão da linhagem PC-3. A FucSulf I foi uma das fucanas que apresentou maior potencial inibitório nas duas linhagens e foi a única que inibiu a adesão da linhagem DU-145 à matriz subendotelial, não interferindo na adesão da linhagem PC-3. A FucSulf I mostrou-se capaz de diminuir também a migração transendotelial das linhagens tumorais DU-145 e PC-3. A heparina mostrou efeito significativo apenas nos ensaios de transmigração, inibindo este evento de forma similar a FucSuf I. Sabe-se que o VEGF aumenta a permeabilidade endotelial, facilitando a passagem de células tumorais através do vaso. Observamos que as duas linhagens secretam VEGF e que a FucSulf I se liga a este fator. Estes dados sugerem que a interação da FucSuf I com o VEGF pode impedir a ação deste fator nas células endoteliais, diminuindo a migração transendotelial das células tumorais testadas. Também verificamos que a FucSulf I inibiu a proliferação das linhagens celulares na ausência de fatores exógenos ou na presença de soro fetal bovino ou VEGF. Por fim, avaliamos que a FucSulf I interfere na ativação de proteínas específicas de vias de sinalização disparadas por fatores de crescimento. A FucSulf I inibe a ativação da AKT na linhagem PC-3, enquanto nas células DU-145 observamos uma inibição da ativação da ERK. Esses dados indicam que a FucSulf I modula diversas etapas da progressão tumoral e pode ser um potencial candidato para o uso em terapias antitumorais / To form metastasis, tumor cells must detach from primary tumor and migrate through the endothelial cell monolayer in direction of the bloodstream (intravasation). Once in the circulation, tumor cells must be able to adhere and migrate across the endothelium (extravasation) towards the target organ, where they will proliferate. Interaction between endothelial and tumor cells is mediated by selectins, followed by the interaction with integrins. Cancer cells frequently exhibit abnormal glycosylation patterns, resulting in the expression of selectins ligands formed by fucosylated polysaccharides, such as sialyl Lewis a/x. During metastatic process, tumor cells secrete several growth factors which can modulate different cell types that are present in the tumor microenvironment. These growth factors can also mediate autocrine signaling and activate signaling pathways involved in tumor cell proliferation and migration. Sulfated polysaccharides, as heparin, may act as P and E-selectin inhibitors as they may also bind to growth factors and interfere in their receptor activation. In this present work, we evaluated the role of sulfated fucans extracted from different marine invertebrates species (L. variegates, S. franciscanus, S. pallidus, A. lixula e S. droebachiensis) in the modulation of the interaction between tumor and endothelial cells in vitro and compared their effect with heparin. We also investigated the role of these molecules in the proliferation of tumor cells. For that, we used two prostate tumor cell lines (DU-145 and PC-3) and a primary culture of human umbilical vein endothelial cells (HUVECs). We first evaluated the effect of the fucans in the tumor cell adhesion to HUVECs. All fucans tested were able to inhibit the interaction between DU-145 and the endothelial cells, while only fucans extracted from L. variegates (FucSulf I) and S. franciscanus were able to inhibit the adhesion of PC-3. FucSulf I showed one of the most striking inhibitory effects in both cell lines and was the only one that inhibited adhesion of DU-145 to subendothelial matrix. It didnt interfere with the adhesion of PC-3 to subendothelial matrix. FucSulf I was also able to decrease transendothelial migration of DU-145 and PC-3. Heparin had significant effect only in the transmigration assays, showing a similar inhibitory potencial in comparison with FucSulf I. VEGF increases endothelial permeability, thus facilitating the migration of tumor cells through the endothelial barrier. We observed that both tumor cell lines secrete VEGF and FucSulf I binds to this factor. These data suggest that the interaction between FucSulf I and VEGF may interfere in endothelial cells response to VEGF, and decrease transendothelial migration of tumor cells. We also showed that FucSulf I inhibits tumor cell proliferation in the absence of exogenous growth factors or in the presence of fetal bovine serum or VEGF. At least, we showed that FucSulf I interfered in the activation of specific proteins involved in signaling pathways triggered by growth factors. FucSulf I inhibited the activation of AKT in PC-3 tumor cell line, while inhibited the activation of ERK in DU-145 tumor cell line. These results indicate that FucSulf I modulates several steps of tumor progression and may be a potential candidate for use in antitumor therapies
49

Einfluss der Chromatinkondensation auf die zelluläre Strahlenempfindlichkeit unter dreidimensionalen Wachstumsbedingungen

Storch, Katja 14 January 2011 (has links) (PDF)
Das Tumormikromilieu beeinflusst maßgeblich Tumorwachstum und -progression sowie das Ansprechen von Tumorzellen auf Strahlen- und Chemotherapie. Weiterhin ist bekannt, dass Wachstumsfaktoren, Sauerstoffgehalt und extrazelluläre Matrix (EZM) als Resistenzfaktoren das Zellüberleben nach Exposition mit ionisierender Strahlung oder zytotoxischen Substanzen bestimmen. Weitere zelluläre Parameter, wie Zellmorphologie, Zytoskelettarchitektur und Chromatinkondensation, werden ebenfalls in Abhängigkeit der Wachstumsbedingungen moduliert, wie vergleichende Untersuchungen an physiologischeren drei- (3D) mit herkömmlichen zwei-dimensionalen (2D) Zellkulturen zeigen. Veränderungen der Chromatindichte beeinflussen zudem die Genexpression, wodurch wichtige zelluläre Prozesse, wie Überleben, Proliferation und Differenzierung der Zellen, reguliert werden. Außerdem ist die Chromatinkondensation für eine effektive Reparatur strahleninduzierter DNA-Schäden, wie DNA-Doppelstrangbrüche (DSB), von großer Bedeutung. Das Ziel der vorliegenden Arbeit bestand darin, die zelluläre Strahlenempfindlichkeit unter Berücksichtigung der Chromatinkondensation in humanen Bronchial- (A549) und Plattenepithelkarzinomzellen (UTSCC-15) in Abhängigkeit der Wachstumsbedingungen zu analysieren. Da die molekularen Mechanismen der Wechselwirkung zwischen Chromatindichte und Reparatur strahleninduzierter DSB bis heute unklar sind, war die Untersuchung dieser Zusammenhänge unter 2D, 3D und in vivo Wachstumsbedingungen von besonderem Interesse. Die Ergebnisse dieser Arbeit zeigen, dass das Zellwachstum in einer physiologischen 3D Matrix im Vergleich zur herkömmlichen 2D Zellkultur zu einer geringeren Anzahl an strahleninduzierten residuellen DSB (rDSB) und letalen Chromosomenaberrationen führen kann, was wiederum für ein verbessertes Zellüberleben nach Bestrahlung verantwortlich sein könnte. Des Weiteren konnte in 3D im Zusammenhang mit einer höheren Chromatinkondensierung eine Erhöhung der zellulären Strahlenresistenz gezeigt werden. Auf molekularer Ebene zeigen die Ergebnisse dieser Arbeit außerdem, dass eine siRNA-vermittelte Hemmung chromatinmodifizierender Histondeacetylasen (HDAC 1, 2 und 4) zu keiner Strahlensensibilisierung führt, während durch die Behandlung mit dem pharmakologischen HDAC-Inhibitor Panobinostat (LBH589) neben der Chromatindekondensierung auch eine erhöhte Strahlenempfindlichkeit der Zellen erreicht werden konnte. In Abhängigkeit der untersuchten Wachstumsbedingungen konnten Unterschiede in der Verteilung strahleninduzierter DSB zwischen hetero- und euchromatischen DNA-Bereichen nachgewiesen werden. Interessanterweise nimmt in 2D dosisabhängig der prozentuale Anteil der Heterochromatin (HC)-assoziierten Foci ab, wohingegen in 3D und im Xenografttumormodell dosisunabhängig etwa die Hälfte der Foci mit heterochromatischen DNA-Bereichen assoziiert sind. Diese Daten zeigen, dass Tumorzellen in 3D und in vivo in Abhängigkeit der veränderten Zellmorphologie und Chromatinkondensierung deutlich mehr HC-assoziierte rDSB besitzen als in 2D, was die Hypothese einer beeinträchtigten Reparatur im HC unterstützt. Dennoch zeigt die Korrelation zwischen der deutlich geringeren rDSB Gesamtanzahl und dem erhöhtem Zellüberleben in 3D, dass neben dem Anteil an kondensiertem Chromatin auch die Gesamtanzahl rDSB ein wichtiger Einflussfaktor der zellulären Strahlenempfindlichkeit zu sein scheint. Die Ergebnisse dieser Arbeit liefern somit wichtige Erklärungsansätze für einen direkten Zusammenhang zwischen Zellmorphologie, Chromatinkondensation und zellulärer Strahlenempfindlichkeit. Des Weiteren unterstreichen diese Untersuchungen das verwendete 3D Zellkulturmodell als Annäherung an die in vivo Situation. Damit sind diese Daten von großer Relevanz für ein besseres Verständnis der zellulären Strahlenempfindlichkeit auf molekularer Ebene und können entscheidend dazu beitragen die Behandlung von Tumorerkrankungen sowie die Heilungschancen der Patienten zu verbessern.
50

Inhibition of NFKB by adenovirus E1A in induction of macrophage senstivity [sic] and reduced tumorigencity [sic] in vivo /

Morris, Kristin Renee. January 2006 (has links)
Thesis (Ph.D. in Immunology) -- University of Colorado at Denver and Health Sciences Center, 2006. / Typescript. Includes bibliographical references (leaves 129-141). Free to UCDHSC affiliates. Online version available via ProQuest Digital Dissertations;

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