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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.
261

Predicting the skin-permeating components of externally-applied medicinal herbs: application of a newly constructed linear free-energy relationship equation for human skin permeation

Zeng, X., Wang, Z., Liu, Xiangli, Chen, M., Fahr, A., Zhang, K. 06 May 2018 (has links)
No / A linear free-energy relationship (LFER) equation that is able to provide a valid prediction of the skin permeability coefficients (log Kp) of neutral molecules, ions and ionic species has recently been constructed and optimized. This study aimed to evaluate the feasibility of predicting the skin-permeating components (SPCs) of externally applied herbs using the LFER equation, with Evodiae fructus (EF) taken as a model herb. The log Kp values of the reported chemical components of EF at pH 4.0 were calculated using the LFER equation and their structural descriptors. The results showed that the essential oils, quinolone, acridone and indole alkaloids of EF are more permeable when compared to other main components, such as phenylpropanoids, furoquinoline alkaloids, limonoids and flavonoids. The SPCs of EF were further collected via ex vivo skin permeation experiments, and analyzed by liquid chromatography-high resolution tandem mass spectrometry. A total of 80 SPCs were detected, and part of them were tentatively identified based on their empirical molecular formulae and MS/MS spectra. The SPCs are made up of 58 alkaloids, including 23 or more quinolone alkaloids, 14 or more indole alkaloids and 1 acridone alkaloid, and 22 non-alkaloids, including 7 or more essential oils and 1 flavonoid, which is in good agreement with the prediction by the LFER equation. It is suggested that a log Kp of −7.0 may be considered as a borderline, above which are potential SPCs and below which are non-SPCs. Very interestingly, the primary SPCs give a good explanation to the antihypertensive action of externally applied EF. To sum up, the LFER equation can be used to predict the SPCs of externally applied herbs, and thus to narrow the range of their potential effective components and speed up the pharmacological study. / This study was supported by the National Natural Science Foundation of China (Grant No. 81703939 and 81503221), the China Postdoctoral Science Foundation (Grant No. 2017M620403), the Project of Industry, Education and Research Funds of Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources (Grant No. FJMBIO1608), the Science and Technology Planning Project of Fujian Province (Grant No. 2017Y4015), the Natural Science Foundation of Guangdong Province (Grant No. 2014A030310365), the Natural Science Foundation of Hubei Province (Grant No. 2014CFC1045) and the Fundamental Research Funds for the Central Universities (Grant No. 20720150069), as well as the Clinical Medical Research Program of Wuhan Health and Family Planning Commission (Grant No. WX15A02).
262

Kan växter lindra klimakteriebesvär? : Behandling av vasomotoriska symptom med hjälp av örtmedicin

Askvärn, Elisabeth January 2016 (has links)
Syftet med detta arbete var att undersöka användningen av örtmedicin vid vasomotoriska symptom i klimakteriet. Frågorna som ställdes var vilka växter som användes, vilka delar av växterna som användes, och hur växtdelarna bereddes och användes. Den sista frågeställningen tog upp hur mycket växterna lindrade de vasomotoriska symptomen. En litteraturstudie genomfördes över vetenskapliga artiklar. I artiklarna användes 20 växter, men endast fem av dessa sas lindra de vasomotoriska symptomen. De fem växterna var Actaea racemosa, Angelica sinensis, Ginkgo biloba, Glycine sp. och Pimpinella anisum.  De växtdelar som oftast användes var rötterna och dessa bereddes ofta genom extrakt som bearbetades för att öka koncentrationen och omvandlas till pulver. Pulvret formades för det mesta till tabletter och kapslar. Ibland saknades information, som vetenskapliga namn på växterna, vilka växtdelar som användes eller hur växterna bereddes. I snitt lindrade växterna de vasomotoriska symptomen med 60 %. De flesta växterna visade sig lindra milda symptom mer än starka symptom. Ett undantag var P. anisum som minskade både antal och styrkan på vallningarna med 74 %. Denna litteraturstudie visar att det finns växter som påverkar de vasomotoriska symptomen i positiv riktning. Samtidigt visar den att informationen i artiklarna ibland är bristfällig och att man inte alltid studerar om växterna kan ge biverkningar. Örtmedicin skulle kunna vara ett alternativ för kvinnor som av olika anledningar inte kan eller vill använda syntetiska hormoner eller andra farmakologiska mediciner, men för att kunna ta in örtmedicin som en del av sjukvården krävs det longitudinella studier som även studerar eventuella biverkningar eller risker för att bättre säkerställa växternas effekt på människokroppen. / The aim of this study was to investigate the use of herbal medicine for vasomotor symptoms during menopause. The questions posed were which herbs that were used, what parts of the herbs that were used, and how the plant parts were prepared and utilized. The last question covered how much the plants alleviated the vasomotor symptoms. A review of the scientific literature was carried out. In the articles, 20 herbs and plants were used, but only five of them were said to relieve the vasomotor symptoms. The five plants were Actaea racemosa, Angelica sinensis, Ginkgo biloba, Glycine sp. and Pimpinella anisum.  The most commonly used parts of the herbs were the roots, often through extracts that were processed in order to increase the concentration and to transform the plant parts into powder. The powder was then for the most part transformed to tablets and capsules. Sometimes, information was missing, such as the scientific names of the plants, what parts of the plants that were used and how the herbs were prepared and utilized. On average, the herbs alleviated the vasomotor symptoms by 60 %. Most of the herbs appeared to relieve mild symptoms more than they alleviated strong symptoms. An exception was P. anisum, which decreased both the amount of and the strength of the flushes by 74 %. This literature study shows that there are plants that influence the vasomotor symptoms in a positive direction. At the same time, it shows that the information in the articles is sometimes incomplete and that the scientists do not always study if the herbs can give side effects. Herbal medicine could be an alternative for women who, for different reasons, cannot or do not want to take synthetic hormones or other pharmacological medicines. However, in order to make herbal medicine part of the treatment offered by public health care, longitudinal studies that also investigate possible side effects or risks are needed for securing the effect of the herbs on the human body.
263

Neuroprotective effects of the active principles from selected Chinese medicinal herbs on b-amyloid-induced toxicity in PC12 cells.

January 2007 (has links)
Hoi, Chu Peng. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 81-103). / Abstracts in English and Chinese. / Acknowledgements --- p.II / Abstract --- p.III / Abstract (in Chinese) --- p.V / List of Abbreviations --- p.VI / List of Figures --- p.VIII / List of Tables --- p.X / Table of Contents --- p.XI / Chapter Chapter One --- General introduction --- p.1 / Chapter 1.1 --- Alzheimer's disease --- p.1 / Chapter 1.1.1 --- Epidemiology and risk factors --- p.2 / Chapter 1.1.2 --- Clinical manifestation and course --- p.4 / Chapter 1.1.3 --- Clinical diagnosis --- p.5 / Chapter 1.1.4 --- Neuropathology and pathogenesis of AD --- p.8 / Chapter 1.1.5 --- Drug therapy of AD --- p.11 / Chapter 1.1.5.1 --- Drugs for symptomatic treatment --- p.11 / Chapter 1.1.5.2 --- Drugs based on epidemiology --- p.12 / Chapter 1.1.5.3 --- Drugs with potential disease-modifying effects --- p.14 / Chapter 1.1.5.4 --- Herbal supplements --- p.15 / Chapter 1.2 --- Models for drug discovery in Alzheimer Disease --- p.15 / Chapter 1.2.1 --- In vivo (animal) models --- p.16 / Chapter 1.2.2 --- In vitro (cellular) models --- p.18 / Chapter 1.3 --- Chinese herbs for the treatment of AD --- p.20 / Chapter 1.3.1 --- Ginkgo biloba L --- p.21 / Chapter 1.3.2 --- Magnolia officinalis --- p.24 / Chapter 1.3.3 --- Acori graminei Rhizoma (AGR) --- p.26 / Chapter 1.3.4 --- Gastrodia elata (G. elata) --- p.27 / Chapter 1.3.5 --- Rhodiola rosea L.( R. rosea) --- p.29 / Chapter 1.3.6 --- Scutellariae baicalensis --- p.30 / Chapter 1.3.7 --- Curcuma longa L.(Zingiberaceae) --- p.31 / Chapter 1.4 --- Aims of the study --- p.33 / Chapter Chapter Two --- Materials and Methods --- p.34 / Chapter 2.1 --- Materials --- p.34 / Chapter 2.1.1 --- Chemicals and reagents --- p.34 / Chapter 2.1.2 --- Materials for cell culture --- p.35 / Chapter 2.1.3 --- Instruments --- p.35 / Chapter 2.2 --- Methods --- p.36 / Chapter 2.2.1 --- Cell culture --- p.36 / Chapter 2.2.2 --- MTT cell viability assay --- p.38 / Chapter 2.2.3 --- Characterization of the cytotoxicity of Aβ peptide in NGF-differentiated PC 12 cells --- p.38 / Chapter 2.2.4 --- Screening of the neuroprotective effect of major principles from selected herbs on PC 12 cells against Aβ-induced cytotoxicity --- p.39 / Chapter 2.2.5 --- Measurement of reactive oxygen species (ROS) --- p.40 / Chapter 2.2.6 --- Measurement of intracellular calcium levels --- p.41 / Chapter 2.2.7 --- Measurement of caspase-3 activity --- p.42 / Chapter 2.2.8 --- Propidium iodide (PI) staining to evaluate apoptosis and necrosis --- p.43 / Chapter 2.3 --- Statistics --- p.45 / Chapter Chapter Three --- Results --- p.46 / Chapter 3.1 --- NGF-differentiated PC 12 cells --- p.46 / Chapter 3.1.1 --- Determination of an appropriate cell density for the screening experiments --- p.46 / Chapter 3.1.2 --- Characterization of Aβ-induced cytotoxicity in NGF-differentiated PC 12 cells --- p.47 / Chapter 3.1.2.1 --- Cytotoxicity of Aβ-related fragments in NGF-differentiated PC 12 cells --- p.48 / Chapter 3.1.2.2 --- Dose-dependent cytotoxic effect of Aβ on PC 12 cells --- p.48 / Chapter 3.1.2.3 --- Time-dependent effect of Aβ-induced toxicity on PC12 cells --- p.50 / Chapter 3.1.3 --- Protective effect of selected active principles against Aβ1-4-induced toxicity in PC 12 cells --- p.51 / Chapter 3.2 --- Measurement of reactive oxygen species (ROS) --- p.54 / Chapter 3.2.1 --- Measurement of ROS induced by H202 --- p.54 / Chapter 3.2.2 --- Measurement of ROS induced by Aβ --- p.56 / Chapter 3.3 --- Measurement of Intracellular calcium levels --- p.57 / Chapter 3.4 --- Measurement of caspase-3 activity --- p.58 / Chapter 3.4.1 --- AMC reference standard curve --- p.59 / Chapter 3.4.2 --- Measurement of caspase-3 activity --- p.59 / Chapter 3.5 --- PI staining for evaluate apoptosis and necrosis --- p.60 / Chapter Chapter Four --- Discussion --- p.64 / Chapter 4.1 --- Aβ-induced cytotoxicity in NGF-differentiated PC 12 cells as an in vitro model of Alzheimer's disease --- p.64 / Chapter 4.1.1 --- Cell line selection --- p.65 / Chapter 4.1.2 --- Characterization of Aβ-induced cytotoxicity in NGF-differentiated PC 12 cells --- p.66 / Chapter 4.2 --- Screening of the neuroprotective effects of selected active principles against Aβ-induced cytotoxicity in NGF-differentiated PC 12 cells --- p.67 / Chapter 4.3 --- Neuroprotection via inhibition of the ROS generation --- p.71 / Chapter 4.4 --- Neuroprotection via suppression of calcium homeostasis --- p.73 / Chapter 4.5 --- Neuroprotective via inhibition of Aβ-induced apoptosis --- p.75 / Chapter 4.5.1 --- Inhibition of caspase-3 activation --- p.75 / Chapter 4.5.2 --- PI staining for evaluation of apoptosis and necrosis --- p.76 / Chapter Chapter Five --- Conclusion and future work --- p.79 / Chapter 5.1 --- Conclusion --- p.79 / Chapter 5.2 --- Future work --- p.80 / References --- p.81
264

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
265

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
266

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.
267

Guidelines on the use of indigenous-western anti-hypertensive therapies in Belize

Husaini, Danladi Chiroma 03 1900 (has links)
This study’s objectives were to identify, describe, and provide guidelines on using indigenous-western antihypertensive therapies in Belize to examine indigenous therapies’ efficacy in lowering blood pressure. The researcher utilized an explanatory sequential mixed method research design to examine indigenous-western therapies. Data were collected quantitatively from the general public (n=422) and qualitatively from hypertensive patients (n=24) using indigenous therapies and vendors (n=19) of indigenous therapies. The study results identified 47 different medicinal plants used in the management of hypertension in Belize, as reported by participants. Besides, leaves were the most reported plant part used to manage hypertension, while boiling (decoction) was the most common preparation method. The common route of administration was the oral route, and ½ to 1 cup 2 to 3 times daily was the dose and frequency of administration, respectively. The majority of participants using indigenous therapies did not report side effects. Conversely, orally administered hydrochlorothiazide and captopril were the most common western therapies reported by most respondents in the study. The majority of the respondents did not report concomitant use of indigenous-western therapies to manage their hypertension; however, those who used indigenous therapies reported that medicinal plants were efficacious in lowering their blood pressure. Some of the claims by participants are verified by Western science, thereby authenticating indigenous therapy claims. The researcher developed guidelines on the use of indigenous-western therapies from the results of the study. Collaboration between indigenous healers and Western medical practitioners to provide holistic healthcare approaches was recommended since both sciences have identical foundations and can learn from each other. The government should incorporate indigenous knowledge systems into school curricula. / Health Studies / Ph. D. (Public Health)
268

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.
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Androgenetic alopecia : a possible treatment and a relationship with hair greying : assessment of the herbal mixture Xiantene for the treatment of androgenetic alopecia and a relationship between early hair greying and the progression of androgenetic alopecia

Davies, Paul Gorton January 2010 (has links)
Hair plays an important role in human social and sexual communication. The androgen-stimulated, patterned loss of hair in cases of androgenetic alopecia (or common baldness) in genetically pre-disposed individuals, is associated with ageing and can cause marked phychological distress. However, it is poorly controlled. To investigate the effectiveness of daily topical application of a Chinese medicine-derived herbal mixture, Xiantene, on balding progression, two double-blind, placebo-controlled studies (3 and 12 months) were carried out on balding men using the trichogram approach. Xiantene significantly increased both the total number of hairs and those in anagen, improving the ratio of anagen:telogen hairs. This suggests that topical Xiantene increased the length of the anagen phase and may promote a cessation, or partial reversal, of the progression of androgenetic alopecia in men. Canities, loss of scalp hair colour, is another mark of ageing. To investigate whether early greying may protect follicles from androgenetic alopecia, the extent of alopecia, assessed using the Hamilton scale, was compared between men who first became grey before, or after, 30. Both alopecia and greying increased with age in 843 men (217 European, 626 Thai) whenever they first started greying. However, men who showed greying before 30 were significantly less bald, though more grey, in both groups. Hair follicle melanocytes synthesise the pigment melanin, producing reactive oxygen species (ROS) and oxidative stress; losing melanocyte pigmentary activity, and therefore these toxic factors, appears to enable hair follicles to maintain their full size for longer, despite the androgen drive to miniaturisation.
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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

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