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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.
81

Study of anti-cancer effect of a Trichosanthes sp. extract.

January 2005 (has links)
Tang Sze-Wan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 104-118). / Abstracts in English and Chinese. / Abstract --- p.i / Abstract (Chinese) --- p.iii / Acknownledgement --- p.iv / List of Abbreviations --- p.v / List of Tables --- p.vii / List of Figures --- p.viii / Table of Contents --- p.xi / Chapter Chapter 1 - --- Introduction / Chapter 1.1 --- Trichosanthes spp --- p.1 / Chapter 1.1.1 --- Use of Trichosanthes --- p.2 / Chapter 1.1.2 --- Trichosanthin --- p.2 / Chapter 1.1.3 --- Karasurin --- p.5 / Chapter 1.1.4 --- Ribosome Inactivating Proteins --- p.6 / Chapter 1.1.5 --- Immunosuppresion --- p.7 / Chapter 1.1.6 --- Anti-Cancer Activity --- p.8 / Chapter 1.1.7 --- Miscellaneous Uses --- p.8 / Chapter 1.2 --- Cancer --- p.9 / Chapter 1.2.1 --- Oncogenes --- p.10 / Chapter 1.2.2 --- Tumor-Suppressor Genes --- p.11 / Chapter 1.2.3 --- Stability Genes --- p.12 / Chapter 1.2.4 --- Types of Cancer --- p.13 / Chapter 1.2.5 --- Cancer Therapy --- p.13 / Chapter 1.2.6 --- Apoptosis --- p.14 / Chapter 1.3 --- Chronic Myelogenous Leukemia (CML) --- p.17 / Chapter 1.3.1 --- Philadelphia Chromosome and BCR-ABL gene --- p.18 / Chapter 1.3.2 --- Treatment of CML --- p.20 / Chapter 1.4 --- Dendritic Differentiation of LC976 on K-562 --- p.20 / Chapter 1.4.1 --- Dendritic Cells --- p.21 / Chapter 1.4.2 --- Cancer Vaccine Development of Leukemia --- p.22 / Chapter 1.4.3 --- Dendritic differentiation of K-562 cells --- p.23 / Chapter 1.5 --- Perspective of the Project --- p.23 / Chapter Chapter 2 - --- Materials and Methods / Chapter 2.1 --- Materials / Chapter 2.1.1 --- Chemicals and Reagents --- p.25 / Chapter 2.1.2 --- Bioassay Kits --- p.26 / Chapter 2.1.3 --- Human Cell Lines --- p.26 / Chapter 2.1.4 --- Lab Wares and Equipments --- p.28 / Chapter 2.2 --- Extraction of LC9 --- p.76 / Chapter 2.2.1 --- Chemical Properties of the Lead Compound --- p.28 / Chapter 2.2.2 --- Crude Extraction of Trichosanthes sp --- p.29 / Chapter 2.2.3 --- Purification by Reversed-Phase Column --- p.29 / Chapter 2.2.4 --- Lyophilization and Preparation of LC976 --- p.31 / Chapter 2.3 --- Anti-Proliferation Effect of LC976 on Human Cell Lines / Chapter 2.3.1 --- Maintenance of Cell Lines --- p.32 / Chapter 2.3.2 --- MTT Assay --- p.32 / Chapter 2.3.3 --- BrdU Cell Proliferation ELISA --- p.34 / Chapter 2.4 --- Apoptosis Induction on K-5 --- p.62 / Chapter 2.4.1 --- PI Staining --- p.35 / Chapter 2.4.2 --- Annexin V-FITC FACS Analysis --- p.36 / Chapter 2.4.3 --- Caspase Activation --- p.37 / Chapter 2.5 --- Effect on Normal Human Lymphocytes / Chapter 2.5.1 --- Preparation of Human Normal Lymphocytes --- p.38 / Chapter 2.5.2 --- MTT Cell Viability Assay --- p.38 / Chapter 2.5.3 --- PI Staining --- p.39 / Chapter 2.5.4 --- Annexin V-FITC FACS Analysis --- p.39 / Chapter Chapter 3 - --- Results / Chapter 3.1 --- Extraction of LC976 --- p.40 / Chapter 3.2 --- LC976 Inhibited Proliferation of Human Cell Lines / Chapter 3.2.1 --- MTT Assay --- p.41 / Chapter 3.2.2 --- BrdU Cell Proliferation ELISA --- p.52 / Chapter 3.3 --- LC976 Induced Apoptosis in K-562 Cells / Chapter 3.3.1 --- PI Staining --- p.63 / Chapter 3.3.2 --- Annexin V-FITC FACS Analysis --- p.70 / Chapter 3.3.3 --- Caspase Activation --- p.73 / Chapter 3.4 --- Effect on Normal Human Lymphocytes / Chapter 3.4.1 --- MTT Cell Viability Assay --- p.76 / Chapter 3.4.2 --- PI Staining --- p.78 / Chapter 3.4.3 --- Annexin V-FITC FACS Analysis --- p.82 / Chapter Chapter 4 - --- Discussion / Chapter 4.1 --- Extraction of LC976 --- p.85 / Chapter 4.2 --- LC976 Inhibited Proliferation of Human Cell Lines / Chapter 4.2.1 --- MTT Assay --- p.86 / Chapter 4.2.2 --- BrdU Cell Proliferation ELISA --- p.88 / Chapter 4.3 --- LC976 induced Apoptosis in K-562 Cells / Chapter 4.3.1 --- PI Staining --- p.90 / Chapter 4.3.2 --- Annexin V-FITC Analysis --- p.95 / Chapter 4.3.3 --- Caspase Activation --- p.96 / Chapter 4.4 --- Effect on Normal Human Lymphocytes / Chapter 4.4.1 --- MTT Cell Viability Assay --- p.98 / Chapter 4.4.2 --- PI Staining --- p.99 / Chapter 4.4.3 --- Annexin V-FITC FACS Analysis --- p.100 / Chapter 4.5 --- Conclusion --- p.103 / Reference --- p.104
82

Effects of tetrandrine on hepatocarcinoma cell lines.

January 2011 (has links)
Yu, Wai Lam. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 79-88). / Abstracts in English and Chinese. / Acknowledgements --- p.IV / Abstract --- p.V / 論文摘要 --- p.VII / Table of Contents --- p.IX / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Cancer --- p.1 / Chapter 1.2 --- Hepatocellular Carcinoma (HCC) --- p.2 / Chapter 1.2.1 --- Risk factors causing HCC --- p.3 / Chapter 1.2.2 --- Molecular mechanism of HCC --- p.7 / Chapter 1.2.3 --- Treatment of HCC --- p.8 / Chapter 1.3 --- Tetrandrine (Tet) - A Natural Compound Derived from Traditional Chinese Medicine (TCM) --- p.10 / Chapter 1.3.1 --- Traditional Chinese Medicine (TCM) --- p.10 / Chapter 1.3.2 --- Tetrandrine (Tet) --- p.12 / Chapter 1.4 --- Molecular View of Apoptosis --- p.14 / Chapter 1.4.1 --- Overview of apoptosis --- p.14 / Chapter 1.4.2 --- Caspase cascade --- p.15 / Chapter 1.4.3 --- Bcl-2 protein family --- p.18 / Chapter 1.4.4 --- The role of mitochondria in apoptosis --- p.20 / Chapter 1.5 --- Anti-cancer Agents Inducing Apoptosis Are New Targets --- p.22 / Chapter 1.6 --- Aim of Study --- p.26 / Chapter Chapter 2 --- Materials and Methods --- p.27 / Chapter 2.1 --- Cell Culture And Treatment --- p.27 / Chapter 2.1.1 --- Cell lines used --- p.27 / Chapter 2.1.2 --- Tetrandrine (Tet) --- p.28 / Chapter 2.1.3 --- Chemicals and reagents 2 --- p.83 / Chapter 2.1.4 --- Solution preparation --- p.29 / Chapter 2.1.5 --- Procedures --- p.30 / Chapter 2.2 --- Cell viability --- p.32 / Chapter 2.2.1 --- Chemicals and reagents . --- p.32 / Chapter 2.2.2 --- Solution preparation --- p.32 / Chapter 2.2.3 --- Procedures --- p.32 / Chapter 2.3 --- Apoptosis detection --- p.34 / Chapter 2.3.1 --- Chemicals and reagents --- p.34 / Chapter 2.3.2 --- Solution preparation --- p.35 / Chapter 2.3.3 --- Procedures --- p.36 / Chapter 2.4 --- Gene expression in tet-induced apoptotic cells --- p.39 / Chapter 2.4.1 --- Chemicals and reagents --- p.39 / Chapter 2.4.2 --- Solution preparation --- p.40 / Chapter 2.4.3 --- Procedures --- p.40 / Chapter 2.5 --- Protein expression in tet-induced apoptotic cells --- p.44 / Chapter 2.5.1 --- Chemicals and reagents --- p.44 / Chapter 2.5.2 --- Solution preparation --- p.45 / Chapter 2.5.3 --- Procedures --- p.48 / Chapter 2.6 --- Cell cycle analysis of tet-treated cells --- p.54 / Chapter 2.5.1 --- Chemicals and reagents --- p.54 / Chapter 2.5.2 --- Solution preparation --- p.54 / Chapter 2.5.3 --- Procedures --- p.54 / Chapter Chapter 3 --- Result --- p.56 / Chapter Chapter 4 --- Discussion --- p.70 / Chapter 4.1 --- Dose- and Time- Dependent Inhibitory Effects of Tet were found on HuH-7 And JHH-4 Cell Lines --- p.70 / Chapter 4.2 --- Tet Is More Selective Towards Liver Cancer Cells --- p.71 / Chapter 4.3 --- The Cell Death in HuH-7 Cells Induced by Tet is Mediated Through Apoptosis --- p.72 / Chapter 4.4 --- Hepatocellular Carcinoma (HCC)Tet Induces G1 Phase Cell Cycle Arrest as Part of Its Mechanism in Inducing Apoptosis in HuH-7 Cells --- p.73 / Chapter 4.5 --- Tet Could Probably Induce G1 Phase Cell Cycle Arrest in JHH-4 Cells --- p.75 / Chapter 4.6 --- "Tet-induced Apoptosis Involves the Intrinsic, Caspase-Dependent Pathway in Both the HuH-7 and JHH-4 Cell Lines" --- p.75 / Chapter 4.7 --- Proteins in Bcl-2 Family are Involved in the Inhibitory Mechanism of Tet --- p.77 / Reference --- p.79
83

Chemical, pharmacological and intestinal absorption studies of stemona alkaloids from radix stemonae. / CUHK electronic theses & dissertations collection

January 2006 (has links)
Finally, intestinal absorption of compounds A and H were also investigated by Caco-2 monolayer cell model. These results demonstrated, for the first time, that these stemona alkaloids were well absorbed in a gastrointestinal cell culture model. Furthermore, compound A was demonstrated to have a marked preference in the basolateral to apical transport direction, and such efflux (basolateral to apical) transport was inhibited by both verapamil and cyclosporine A, P-glycoprotein (P-gp) inhibitors, but not by probenecid and MK371, multidrug resistant-associated protein (MRP) inhibitors. The results suggested that compound A transported through active efflux mechanisms via P-gp but not MRP pathway. / High performance liquid chromatography (HPLC) coupled with evaporative laser scattering detector (ELSD) was developed to qualitatively and quantitatively determine the chemical profiles of Radix Stemonae. The results demonstrated that the type and quantity of the main bioactive ingredients, stemona alkaloids, present in various herbal samples varied significantly. Compound A (neotuberostemonine) was identified as a predominant alkaloid in two commercial Radix Stemonae samples, whereas compound F (croomine), compound H (tuberostemonine) and compound G (oxoneotuberostemonine) were identified as the major alkaloids present in other three commercial samples, respectively. Chemical variations were observed in several fresh Radix Stemona samples collected in mainland China. These chemical variations might be due to species and/or environmental differences. / In addition to the antitussive activities, it was found that a high dose of compound A caused markedly behavioral changes, including head and body shaking via both intraperitoneal and intracerebroventricular administration. Such adverse effect was abolished by a centrally acting dopamine D2 antagonist haloperidol, suggesting that a central dopaminergic effect might contribute to the behavioral activities produced by compound A. Moreover, compound A was found, for the first time, to dose-dependently and competitively inhibit monoamine oxidase (MAO)-B and compound A was identified to be a weak and non-competitively inhibitor on MAO-A. It was further demonstrated that compound A increased the intercellular concentration of dopamine in the cultured PC12 cells and prevented MPTP-induced cell death in PC12 cells via inhibition of MAO. Therefore, the behavioral changes induced by compound A was suggested to be involved with dopaminergic pathway via reduction of dopamine metabolism caused by inhibition of MAO. / On the other hand, compound F was demonstrated to cause acute lethal toxicity via intraperitoneal but not via oral administration. The results suggested that compound F might have a low oral bioavaiIability. Further absorption study by Caco-2 model demonstrated that this alkaloid had a good intestinal absorption, thus its low oral bioavailability could be due to extensive first-pass effects in the gastrointestinal tract. / Pharmacological properties of stemona alkaloids were studied in vivo using the citric acid-induced guinea pig cough model. The three stemona alkaloids present in different Radix Stemonae samples were all found to be antitussive. Compounds A and H were both orally active and had similar antitussive potencies via both oral and intraperitoneal (i.p.) administrations. Compound F was demonstrated to be antitussive via i.p. administration only. The mechanism of antitussive activity of the representative stemona alkaloid, compound A, was further investigated. However, none of the currently known antitussive pathways were identified to be involved in compound A. Thus, compound A and also other stemona alkaloids are likely to produce their antitussive activity via a novel pathway. / Radix Stemonae is derived from the root tubes of three different species of Stemona genus (Stemonaceae). This herb has been prescribed in traditional Chinese medicine (TCM) as an antitussive agent for over thousands of years. To date, over fifty stemona alkaloids have been identified from various Stemona species. However, there is a lack of direct evidence to link stemona alkaloids to the effectiveness of the herb in the treatment of cough. The aim of the present study is to investigate Stemona species used as plant sources for Radix Stemonae, the chemical and pharmacological properties in relation to antitussive activity of the herb, and the intestinal absorption of the main bioactive constituents, stemona alkaloids, in the herb. / The identity of fresh Radix Stemonae samples was investigated using a DNA based polymorphism assay. 5S-rRNA, ITS-1 and ITS-2 are highly conserved spacer regions; thus, the diversity of these spacer regions was used for the identification of Radix Stemonae samples. The amplified spacer regions of different Radix Stemona samples collected from different geographical locations in Mainland China were sequenced and compared. The result demonstrated that there were at least three different DNA patterns among seven samples examined and this DNA sequential assay could distingue species in Stemona genus from species in other genera. However, the findings suggested that the variation in chemical profiles of different Radix Stemonae samples was not directly related to their DNA sequences. DNA sequential method could be used to authenticate the correct plant sources for Radix Stemonae but it can not to provide information on chemical profiles of the herb. / The overall results demonstrated that the quantities and types of stemona alkaloids varied significantly depending upon plant sources. Furthermore, these stemona alkaloids differed considerably in pharmacological activities, toxicological effects and absorption profiles. Therefore, these variations in different Radix Stemonae samples may lead to different therapeutic outcomes, including efficacies, adverse effects, and potential herb-drug and herb-herb interactions. Nevertheless, the present study provided a scientific basis for the therapeutic use of Radix Stemonae and illustrated a potential for the development of herbal Radix Stemonae or pure stemona alkaloids into a new class of antitussive TCM herbal products or TCM-based agents in the future. / Leung Pak Ho Henry. / "January 2006." / Adviser: Ge Lin. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6328. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 179-197). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
84

Pharmacological, phytochemical and safety evaluaton of commercial herbal preparations common in South Africa.

Ndhlala, Ashwell Rungano. January 2009 (has links)
Herbal formulations claimed to cure several medical conditions including skin eruptions, chest pains, wounds, gout, menstrual pains, stress, nervous disorders, microbial and viral infections as well as stomach ailments have recently appeared as part of South African traditional medicine. The formulations consist of mixtures of extracts of different plant parts from several different plant species packaged in labelled bottles or boxes. The mixtures are available for sale in herbal shops and public places. While there has been widespread use of these herbal mixtures, there has been no scientific evidence to support their use. This project was aimed at documenting, validating claimed efficacy and testing the safety of fourteen unregistered commercial herbal preparations commonly sold in Pietermaritzburg. A detailed investigation of the pharmacological effects and safety of the plant components of one of the mixtures, Imbiza ephuzwato was also carried out. / Thesis (Ph.D.) - University of KwaZulu-Natal, Pietermaritzburg, 2009.
85

Anti-carcinogenic activity of Centella asiatica and Elytropappus rhinocerotis on a human colon cancer cell line

Dwarka, Depika January 2012 (has links)
Submitted in complete fulfillment for the Degree of Master of Technology: Biotechnology, Durban University of Technology, 2012. / Recently our understanding of cancer has advanced in the realization that apoptosis and the genes that control it have a profound effect on the malignant phenotype. It is now clear that some oncogenic mutations disrupt apoptosis, leading to tumor initiation, progression or metastasis. Conversely, compelling evidence indicates that other oncogenic changes promote apoptosis, thereby producing selective pressure to override apoptosis during multistage carcinogenesis. Finally, it is now well documented that most cytotoxic anti-cancer agents induce apoptosis, raising the intriguing possibility that defects in apoptotic programs contribute to treatment failure. Because the same mutations that suppress apoptosis during tumor development also reduce treatment sensitivity, apoptosis provides a conceptual framework to link cancer genetics with cancer therapy. An intense research effort is uncovering the underlying mechanisms of apoptosis, such that, in the next decade, one envisions that this information will produce new strategies to exploit apoptosis for therapeutic benefit. Plants have a long history in cancer treatment. More than 3000 species have been known for their anti-cancer potential. Over 60% of currently used anti-cancer agents are derived in one way or another from higher plants. Indeed, compounds derived from natural sources, including plants, have played, and continue to play, a dominant role in the discovery of leads for the development of conventional drugs for the treatment of most human diseases especially cancer. Thus the aim of this study was to investigate if Centella asiatica and Elytropappus rhinocerotis possess anti-cancer potential and determine the effect on the modulation of apoptosis. In South Africa C. asiatica is known anecdotally to treat various forms of cancers and E. rhinocerotis is known to treat colic and diarrhoea. The anti-cancer activity of C. asiatica has been studied in some parts India but E. rhinocerotis has not been investigated. This study was conducted using polarity guided fractionation (aqueous, ethanolic, methanolic and hexane), thereafter these extracts were tested for their toxicity on a colon cancer cell line (CaCO-2) and on normal cells vi (PBMC). Subsequently, the most active extract was used to isolate the active fraction. The fraction that displayed toxicity on the CaCO-2 cells were further investigated for their ability to induce apoptosis by observing the morphological effects and DNA changes using acridine orange-ethidium bromide staining. Apoptosis was confirmed using Annexin V- PI staining. Nuclear effects were studied by DNA fragmentation and by agarose gel electrophoresis. Nuclear fragmentation was studied by flow cytometry using bromodeoxyuridine (BrDU). Pro-apoptotic changes were determined with Caspase III enzyme levels using flow cytometry. The results were compared to the effect of a known anti-carinogen - Taxol. The anti-oxidant activity was also evaluated for the different extracts. The ethanolic extracts of both C. asiatica and E. rhinocerotis showed more than 100% radical scavenging activity. The methanolic extract (125 μg/ml -500 μg/ml) showed cytotoxicity on the CaCO-2 cells and a proliferative effect on the PBMC. Apoptosis was confirmed in the methanolic extract for both plants and was therefore used to carry forth this study. This included early apoptotic changes observed by the morphological study i.e., membrane blebbing, nuclear condensation and the presence of apoptotic bodies, in both C. asiatica and E. rhinocerotis fractions demonstrated more non-viable apoptotic cells than the methanolic extracts. Late changes of apoptosis were also found as indicated by DNA laddering and a positive outcome with BrDU. Both the active fractions from C. asiatica and E. rhinocerotis showed more DNA laddering and active caspase III than the methanolic extract. These features indicate that C. asiatica and E. rhinocerotis cause apoptotic death of colon cancer cells CaC0-2. In conclusion, there was a significant increase in apoptosis of CaCO-2 cells with little alteration of PBMC in the presence of the methanolic extract of C. asiatica and E. rhinocerotis. The semipure fractions resulted in changes related to late apoptosis. The results suggest that C. asiatica and E. rhinocerotis induces apoptosis in CaCO-2 cells which is an important step in elucidating the underlying molecular mechanism for anti-tumour activity.
86

An investigation of the rate of change of CD4 and CD8 T lymphocyte counts and viral loads in HIV infected patients on immune boosters

Mkhize, Brenda Thabisile January 2007 (has links)
A thesis submitted in partial fulfilment of tine requirements for the Degree of Master of Technology: Biomedical Technology, Durban University of Technology, 2007. / In 2004, it was reported that KwaZulu-Natal had the greatest number of HIV infected people, approximately 1.8 million people, of whom an estimated 450 000 were in need of antiretroviral drug therapy based on their Cluster of Differentiation 4 (CD4) counts and clinical status. Studies on the success of antiretroviral drugs in improving the quality of life in HIV infected individuals have been extensively performed and published. However, there are no published data on the effect that immune boosters have in improving the quality of life in such persons. Considering the side effects, toxicity, multi-drug regimens and drug resistance problems associated with antiretroviral therapy, alternative or supplementary therapies may play an important role in improving the quality of life in HIV infected people. Such therapy might help in situations where some patients who qualify for antiretroviral treatment are unable to access them because of several reasons such as long waiting lists, travelling costs, unwilling to take antiretroviral drugs, etc. Some patients have reservations in taking antiretroviral drugs. The stigma associated with the disease may be a major factor. The aim of this study was to investigate the change in the immune status of HIV infected patients that were on the Inochi New Medicine immune booster, as well as, to assess the safety and efficacy of this immune booster in improving the patients’ quality of life. / M
87

Hepatoprotection of the traditional Chinese medicinal formula Wu-zi-yan-zong-wan against chronic alcohol-induced injury. / CUHK electronic theses & dissertations collection

January 2008 (has links)
Finally, the hepatoprotection of the 50%EtWZ was evaluated using rat model. The results indicated that the 50%EtWZ possessed potent hepatoprotective activities. The protective effect of the extract against hepatotoxicity induced by long-term treatment with ethanol might be attributed to its inhibitory action on oxidative stress. Although multiple factors could be involved in the inhibition of oxidative injury in the liver, the inhibition of CYP2E1 pathway and the enhanced GSH-related antioxidant capacity might be responsible for the protective effect. In addition, the 50%EtWZ also produced anti-inflammatory effect partly by interfering Toll-Like-Receptor-4 (TLR-4)-mediated signal pathway and reducing the production of Tumor Necrosis Factor-alpha (INF-alpha) in Kupffer cells during long-term ethanol exposure. / First, in order to determine which kind of extract possesses the strongest hepatoprotective effect on ethanol-induced cytotoxicity, various extracts were screened for cytochrome P450 2E1 isoenzyme (CYP2E1) inhibitory activity using the fluorogenic CYP2E1 substrate and HepG2 cells overexpressing human CYP2E1. The results showed that all extracts (aqueous, 50% ethanol, and 90% ethanol) of WZ produced inhibitory effect on CYP2E1. The 50% ethanol extract of WZ (50%EtWZ) displayed a stronger CYP2E1 inhibition than the aqueous and 90% ethanol extracts. The aqueous extract and 50%EtWZ showed protective effect against ethanol-induced cytotoxicity at concentrations equivalent to 100 and 1000 mug raw herb/ml. At the same concentration of 100 1.1g/ml, the 50%EtWZ exhibited a more potent protective effect. Higher degree of cytotoxicity was found in the 90% ethanol extract of WZ. Thus, 50%EtWZ was chosen for further study. / In summary, all data suggest that the inhibition of CYP2E1 pathway and the inhibition of oxidative stress by the 50%EtWZ, together with the anti-inflammatory effect on Kupffer cells, may contribute to its hepatoprotection against chronic ethanol-induced liver injury. / Second, the chemical components of the 50%EtWZ were analyzed by chromatographic fingerprints. The fingerprint revealed six hepatoprotective compounds including schisandrin B, schisandrin, deoxyschisandrin, betaine, hyperin, and quercitrin in the formula. / Third, the protective mechanism of the 50%EtWZ was investigated in E47 cells model. The 50%EtWZ protected against CYP2E1-dependent toxicity and oxidative stress induced by ethanol. The mechanism of protection involved the decrease of reactive oxygen species production and the inhibition of lipid peroxidation. The hepataprotection was associated with the maintenance of mitochondrial GSH. Pre-treating E47 cells with the 50%EtWZ significantly inhibited the expression of CYP2E1. Therefore, the protective effect of the 50%EtWZ was most likely attributed to its antioxidant activities and the inhibition of CYP2E1. In addition, the 50%EtWZ prevented ethanol-induced apoptosis and protected against oxidative damage to mitochondria which are critical for maintenance of cell viability. / Wu-Zi-Yan-Zong-Wan (WZ), a traditional medicinal formula, is used for treatment of male sexual dysfunctions. In this study, the hepatoprotection afforded by Wu-Zi-Yan-Zong-Wan treatment and its biochemical mechanism involved against chronic alcohol-induced injury were investigated. / Chen, Mengli. / "May 2008." / Adviser: Che Chun Tao. / Source: Dissertation Abstracts International, Volume: 70-03, Section: B, page: 1609. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (p. 157-179). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
88

Biological effects of herbal molecules in ocular neovascularization in vitro and in vivo. / 中藥分子對眼部新生血管生物作用的體內、體外的研究分析 / CUHK electronic theses & dissertations collection / Zhong yao fen zi dui yan bu xin sheng xue guan sheng wu zuo yong de ti nei, ti wai de yan jiu fen xi

January 2010 (has links)
Angiogenesis is a process of new blood vessels sprouting from the pre-existing vasculature, and mediated by multiple angiogenic and anti-angiogenic factors. Disturbance of the balance often leads to development of neovascular diseases. Neovascularization affecting the eye is a common cause of visual impairment and even blindness, particularly when corneal or choroidal neovascularization (NV) is involved. While there are effective treatment modes for ocular neovascularization, they are expensive and only inhibit disease progress. Since herbal medicine has been applied for anti-angiogenesis and anti-carcinogenesis therapies, we investigate the anti-angiogenic effect of selected herbal molecules: isoliquiritigenin (ISL), a flavonoid from licorice; epigallocatechin gallate (EGCG), a polyphenol from green tea; and resveratrol (Rst), a polyphenol phytoalexin derived from grapes. / In conclusion, by in vitro and in vivo studies, we showed that ISL, EGCG and Rst contributed to anti-angiogenesis via different biological mechanisms. We propose that these three herbal molecules (ISL, EGCG and Rst) are candidate anti-angiogenic agents for the treatment of ocular angiogenesis diseases. Their distribution profiles and pharmacokinetic properties should be investigated. / Results showed that sub-toxic levels of ISL (10 microM), EGCG (50 microM) and Rst (10microM) effectively suppressed endothelial cell proliferation and migration in the scratch-wound assay. Treatment with ISL was found to significantly up-regulate PEDF, which is known as a potent angiostatic factor. EGCG and Rst downregulate VEGF signaling cascade by suppressing Akt and FAK activation and affecting MMP-2, MMP-9 expression. In vivo angiogenesis assays further showed the suppressive effect of ISL, EGCG and Rst on neovascularization in three different animal models. Application of ISL at 1 microM showed the suppressive effect on chick CAM assay, corneal NV and choroidal NV assays consistently, the most effective dosage was close to 10 microM. EGCG at 1 microM showed the effect to reduce chick CAM vessel formation and corneal NV, and at 10 microM (the lowest tested concentration) to suppress choroidal NV in mice. Variable effects were observed in Rst treatment. Rst at 10 microM prohibited vessel growth in chick CAM, and 1 microM suppressed corneal NV formation and 2 microM deterred choroidal NV development. / This thesis contains two major parts. The first in vitro cell-based analysis investigated the toxicity of these herbal chemicals and their effect on endothelial cell growth and migration. The expression profile of vascular endothelial growth factor (VEGF) signaling cascade events, including Akt and focal adhesion kinase (FAK) activation, VEGF, pigment epithelium-derived factor (PEDF) and matrix metalloproteinases (MMPs) were examined by Western blotting. Then three in vivo models were established to study the effect of these herbal chemicals on angiogenesis. They were (1) developmental angiogenesis in chick chorioallantoic membrane (CAM), (2) pathological angiogenesis in silver nitrate cauterization-induced corneal neovascularization in BALB/c mice and, (3) laser photocoagulation-induced choroidal neovascularization in C57BL/6 mice. Changes of vascularization were determined by qualification of vessel number changes on the edge of gelatin sponge in 24 hours (chick CAM assay), measurement of vascularized area, live imaging of vessel leakage (fundus fluorescence angiography, FFA) and immunochemistry using antibodies specific for endothelial cells (corneal & choroidal NV assays) respectively. / Liu, Huanming. / Adviser: Chi Pui Pang. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 155-180). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
89

Molecular authentication of epimedium species and the anti-osteoporosis effect of herba epimedii. / CUHK electronic theses & dissertations collection / Digital dissertation consortium

January 2004 (has links)
Sun Ye. / "November 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 205-225) / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
90

Mechanistic study of herb-drug interactions between oseltamivir and TCM formulae. / Mechanistic study of herb-drug interactions between oseltamivir and traditional Chinese medicine formulae

January 2010 (has links)
Wang, Xiaoan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 145-166). / Abstracts in English and Chinese. / Table of Contents --- p.I / Acknowledgements --- p.VI / Publications --- p.VII / Abstract (in English) --- p.VIII / Abstract (in Chinese) --- p.X / List of Figures --- p.XII / List of Tables --- p.XVI / List of Abbreviations --- p.XVII / Chapter Chapter One. --- Introduction --- p.1 / Chapter 1.1 --- Overview of oseltamivir --- p.1 / Chapter 1.1.1 --- General description of oseltamivir --- p.1 / Chapter 1.1.2 --- Pharmacological activities of oseltamivir --- p.3 / Chapter 1.1.3 --- Pharmacokinetics of oseltamivir --- p.3 / Chapter 1.1.3.1 --- Absorption of oseltamivir --- p.4 / Chapter 1.1.3.2 --- Distribution of oseltamivir --- p.5 / Chapter 1.1.3.3 --- Metabolism of oseltamivir --- p.6 / Chapter 1.1.3.4 --- Elimination of oseltamivir --- p.8 / Chapter 1.1.4 --- Side effects and toxicities of oseltamivir --- p.9 / Chapter 1.2 --- Overview of Chinese medicine formulae CMF1 (Yinqiaosan and Sangjuyin) --- p.9 / Chapter 1.2.1 --- Background and clinical use of CMF1 --- p.9 / Chapter 1.2.2 --- Quality control of CMF1 by manufacturer --- p.11 / Chapter 1.2.3 --- Major active components of CMF1 --- p.12 / Chapter 1.3 --- Previous studies on herb-drug interactions between O and CMF1 --- p.18 / Chapter 1.4 --- Rationale of the current study --- p.19 / Chapter 1.5 --- objectives --- p.19 / Chapter Chapter Two. --- Identification and quantification of major marker compounds in Yinqiaosan and Sangiuyin products --- p.20 / Chapter 2.1 --- Introduction --- p.20 / Chapter 2.2 --- Materials and methods --- p.23 / Chapter 2.2.1 --- Chemicals --- p.23 / Chapter 2.2.2 --- Instruments --- p.24 / Chapter 2.2.3 --- Chromatographic conditions --- p.24 / Chapter 2.2.4 --- Preparation of standard solutions --- p.25 / Chapter 2.2.5 --- Calibration curves --- p.26 / Chapter 2.2.6 --- Validation of the assay method --- p.26 / Chapter 2.2.7 --- Sample preparations for Yinqiaosan and Sangjuyin products --- p.27 / Chapter 2.2.7.1 --- Sample extraction from Yinqiaosan or Sangjuyin granules --- p.27 / Chapter 2.2.7.2 --- Sample extraction from Yinqiaosan or Sangjuyin tablets --- p.27 / Chapter 2.2.7.3 --- Sample extraction recoveries --- p.27 / Chapter 2.3 --- Results and discussions --- p.28 / Chapter 2.3.1 --- Chromatography --- p.28 / Chapter 2.3.2 --- Linearity and sensitivity --- p.33 / Chapter 2.3.3 --- Accuracy and precision --- p.33 / Chapter 2.3.4 --- Stability --- p.36 / Chapter 2.3.5 --- Contents of identified active components in commercial available Yinqiaosan or Sangjuyin products and CMF1 --- p.36 / Chapter 2.3.6 --- Sample extraction recovery --- p.40 / Chapter 2.4 --- Conclusion --- p.43 / Chapter Chapter Three. --- Effect of CMF1/CMF1 components on the metabolism of oseltamivir and related mechanistic studies --- p.44 / Chapter 3.1 --- Introduction --- p.44 / Chapter 3.2 --- Materials and methods --- p.47 / Chapter 3.2.1 --- Materials --- p.47 / Chapter 3.2.2 --- "Verification of metabolism of O in rat GI tract, plasma and liver microsome" --- p.48 / Chapter 3.2.3 --- Inhibition of metabolism of O by CMFl/CMFl components --- p.49 / Chapter 3.2.3.1 --- In vitro inhibition of metabolism of O in rat plasma --- p.49 / Chapter 3.2.3.2 --- In vitro inhibition of metabolism of O in rat liver microsome (RLM) --- p.49 / Chapter 3.2.4 --- Mechanistic study of enzyme inhibition of O in recombinant human Carboxylesterase 1 (hCE 1) --- p.50 / Chapter 3.2.5 --- Sample preparation and LC/MS/MS analysis --- p.50 / Chapter 3.2.6 --- Data analyses --- p.52 / Chapter 3.3 --- Results --- p.53 / Chapter 3.3.1 --- "Verification of metabolism of O in rat GI tract, plasma and liver microsome" --- p.53 / Chapter 3.3.2 --- Inhibition of metabolism of O by CMF1/CMF1 components --- p.53 / Chapter 3.3.2.1 --- Enzyme inhibition of metabolism of O by CMFl/CMF1 components in rat plasma --- p.53 / Chapter 3.3.2.2 --- Enzyme inhibition of metabolism of O by CMF1/CMF1 components in rat liver microsome (RLM) --- p.58 / Chapter 3.3.2.3 --- Selection of potent enzyme inhibitor from CMF1 --- p.60 / Chapter 3.3.4. --- Mechanistic study of enzyme inhibition of O in recombinant human Carboxylesterase 1 (hCE 1) --- p.61 / Chapter 3.4 --- Discussions --- p.63 / Chapter 3.5 --- Conclusion --- p.74 / Chapter Chapter Four. --- Effect of CMFl/CMFl components on the absorption of oseltamivir and related mechanistic studies --- p.75 / Chapter 4.1 --- Introduction --- p.75 / Chapter 4.2 --- Materials and methods --- p.79 / Chapter 4.2.1 --- Materials --- p.79 / Chapter 4.2.2 --- PAMPA permeation model --- p.80 / Chapter 4.2.2.1 --- Permeation of O and OC in PAMPA --- p.80 / Chapter 4.2.2.2 --- Sample preparation and LC/MS/MS analysis --- p.81 / Chapter 4.2.2.3 --- Data analysis --- p.81 / Chapter 4.2.3 --- Absorption of O in presence of CMF/CMFl components in Caco-2 and MDCK cell monolayer models --- p.82 / Chapter 4.2.3.1 --- Cell culture --- p.82 / Chapter 4.2.3.2 --- Preparation of loading solutions to the cell models --- p.83 / Chapter 4.2.3.3 --- Stability of O in transport buffer --- p.84 / Chapter 4.2.3.4 --- Cytotoxicity tests of O and CMFl/CMFl components --- p.84 / Chapter 4.2.3.5 --- Transport study in Caco-2 and MDCK monolayer model --- p.85 / Chapter 4.2.3.6 --- Sample preparation and LC/MS/MS analysis --- p.86 / Chapter 4.2.3.7 --- Data analysis --- p.87 / Chapter 4.2.4 --- Absorption of O in presence of CMF 1 in rat in situ single pass intestinal perfusion model --- p.88 / Chapter 4.2.4.1 --- Preparation of perfusion solutions --- p.88 / Chapter 4.2.4.2 --- Stabilities of O and arctigenin in perfusate --- p.88 / Chapter 4.2.4.3 --- Rat in situ single pass intestinal perfusion of O in presence and absence of CMFl and relevant inhibitors --- p.89 / Chapter 4.2.4.4 --- Sample preparation and LC/MS/MS analysis --- p.90 / Chapter 4.2.4.5 --- Data analysis --- p.90 / Chapter 4.3 --- Resul ts --- p.91 / Chapter 4.3.1 --- Permeation of O and OC in PAMPA --- p.91 / Chapter 4.3.2 --- Absorption of O in presence of CMF/CMF1 components in Caco-2 and MDCK cell monolayer models --- p.92 / Chapter 4.3.2.1 --- Stabilities of O in transport buffer --- p.92 / Chapter 4.3.2.2 --- Cytotoxicity tests of O and CMF1/CMF1 components in transport buffer --- p.93 / Chapter 4.3.2.3 --- Proof of O as a substrate of P-gp by Caco-2 cell model --- p.95 / Chapter 4.3.2.4 --- Effect of CMF 1 on the absorption transport of o in Caco-2 cell mode --- p.98 / Chapter 4.3.2.5 --- Effect of CMF1 components on the absorption transport of o in Caco-2 cell model --- p.102 / Chapter 4.3.2.6 --- Effect of arctigenin on bi-directional transport of o in Caco- 2 cell model --- p.106 / Chapter 4.3.2.7 --- Proof of O as a substrate of P-gp by MDCK transfected cell lines --- p.108 / Chapter 4.3.2.8 --- Bi-directional transport of O in MDCK-MDR1 cell model --- p.111 / Chapter 4.3.2.9 --- Effect of CMF 1 on the absorption transport of O in MDCK-MDR1 cell model --- p.112 / Chapter 4.3.3 --- Absorption of O in presence of CMF1 in rat in situ single pass intestinal perfusion model --- p.113 / Chapter 4.3.3.1 --- Stabilities of O and arctigenin in the perfusion buffer --- p.113 / Chapter 4.3.3.2 --- Intestinal absorption of O in presence and absence of CMF1 in rat in situ intestinal perfusion model --- p.114 / Chapter 4.4 --- Discussions --- p.116 / Chapter 4.5 --- Conclusion --- p.124 / Chapter Chapter Five. --- Preliminary evaluation of antiviral activity of CMFl/CMFl components --- p.125 / Chapter 5.1 --- Introduction --- p.125 / Chapter 5.2 --- Materials and methods --- p.128 / Chapter 5.2.1 --- Materials and animals --- p.128 / Chapter 5.2.2 --- Animal treatment --- p.129 / Chapter 5.2.3 --- Plasma sample collection and preparation --- p.130 / Chapter 5.2.4 --- Evaluation of antiviral activities of CMFl/ CMFl components --- p.130 / Chapter 5.2.4.1 --- Plaque reduction assay --- p.131 / Chapter 5.2.4.2 --- Optimization of plasma sample dilution ratio --- p.131 / Chapter 5.2.5 --- Data analyses --- p.133 / Chapter 5.3 --- Results and discussions --- p.135 / Chapter 5.3.1 --- Ex vivo evaluation of antiviral activity of CMF1 --- p.135 / Chapter 5.3.2 --- In vitro evaluation of antiviral activity of CMF1 major marker compounds --- p.139 / Chapter 5.4 --- Conclusion --- p.141 / Chapter Chapter Six. --- Overall conclusion --- p.142 / References --- p.145

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