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Metabolomic strategies for early diagnosis of myasthenia gravis and efficacy evaluation of Qiangji Jianli Fang.January 2013 (has links)
重症肌無力是由自身抗體在神經肌肉接頭特異性的結合乙酰膽鹼受體和肌肉特異性激酶引起的一種獲得性免疫性疾病。疾病的主要症狀是骨骼肌的軟弱無力和易疲勞性。這一症狀在運動後尤為顯著,休息後會有所緩解。重症肌無力在世界範圍的發病率是百萬分之三到三十。由於近年來患者的數量在不斷增加,重症肌無力引起了醫學界的廣泛關注。但是,目前的診斷和治療措施還不能完全滿足臨床病人的需要。在本課題研究中,我們希望運用代謝組學的手段建立一種新的更加有效可靠的方法用於重症肌無力的診斷。同時,我們希望在代謝物的水平上來闡釋強肌健力方(一種中藥復方)對重症肌無力的治療作用。 / 本研究所用樣本來自42個重症肌無力病人和16個健康志願者。樣本由廣州中醫藥大學第一附屬醫院於二零零七年到二零零八年收集所得。診斷後,病人每日口服一定劑量的強肌健力方接受治療,連續服藥兩個月。分別在服藥前和治療後對病人抽血採樣。進一步分離血清後,樣品進行質譜分析。多元統計學方法如主成分分析,正交偏最小二乘和正交偏最小二乘判別分析等用於質譜數據的分析。 / 通過和健康者比較分析,我們在重症肌無力病人的血液中找到142個顯著改變的離子。其中,14個離子得到鑒定,包括:γ-氨基丁酸,2-哌啶酸,鳥氨酸,5,8-十四碳二羧酸,精胺,己酰肉毒鹼,N-油酰基甘氨酸,鞘氨醇-1-磷酸,聯原膽酸,糞甾烷酸,植物鞘氨醇-1-磷酸,鵝去氧膽酸甘氨酸結合物,輔酶Q4和甘氨酸膽。基於以上142個離子建立的數學診斷模型在診斷重症肌無力時表現出很高的靈敏度和特異性,分別高達92.8%和83.3%。強肌健力方能夠逆轉由重症肌無力引起的特異性代謝變化,將病人體內被改變的代謝網絡恢復正常,特別是大部分的代謝標誌物在治療後都恢復到了相對正常水平,包括:γ-氨基丁酸,哌啶酸,鳥氨酸,5,8-十四碳二羧酸,精胺,己酰肉毒鹼,N-油酰甘氨酸,鞘氨醇-1-磷酸,聯原膽酸,輔酶Q4和甘氨酸膽。 / 本研究揭示了基於液質聯用的代謝組學方法適用於探索重症肌無力的代謝標誌物,並提供了一種可用於診斷重症肌無力的新方法。同時,本研究證實強肌健力方適用於重症肌無力的治療,且無明顯副作用。 / Myasthenia gravis (MG) is an acquired autoimmune disease caused by specific autoantibodies against acetylcholine receptors (AChRs) and muscle-specific kinase (MuSK) proteins at the neuromuscular junctions. The disease is characterized by weakness and fatigability of the voluntary muscles that gets worse with exertion and improves with rest. The global incidence rate of MG is about 3-30 cases per million per year. In recent years, the worldwide prevalence rate of MG is increasing as a result of increased awareness. However, current diagnostic measures and treatments are not conclusive and satisfactory for MG. In this study, a mass spectrometry-based metabolomic strategy was applied to develop a novel and reliable diagnostic measure for MG on the basis of metabolic analysis, and to explore the therapeutic effect of Qiangji Jianli Fang (QJF, a newly developed Chinese medicine formula) on MG at the metabolite level. / Total 42 MG patients (13 males and 29 females) and 16 volunteers (5 males and 11 females) were recruited at the First Affiliated Hospital of Guangzhou University of Chinese Medicine between March 2007 and March 2008. The patients took QJF once per day for 2 months. Peripheral blood from patients was collected at diagnosis and after 2-month treatment, respectively. Sera prepared from the blood samples were monitored by the liquid chromatography Fourier transform mass spectrometry (LC-FTMS). Mass spectral data were analyzed by multivariate statistical analyses, including principal component analysis (PCA), orthogonal partial least squares (OPLS), and orthogonal partial least squares discriminant analysis (OPLS-DA). / By comparing analysis with the healthy volunteers, 142 significantly changed ions from serum metabolic profile of MG patients were picked out as the potential biomarkers of MG. Among of them, 14 ions were temporarily identified. They were gamma-aminobutyric acid (GABA), pipecolic acid, ornithine, 5,8-tetradecadienoic acid, spermine, hexanoylcarnitine, N-oleoyl glycine, sphingosine-1-phosphate (S1P), bisnorcholic acid, coprocholic acid, phytosphingosine-1-P, chenodeoxycholylglycine, coenzyme Q4, and cholylglycine. The developed OPLS-DA diagnostic model based on the 142 special ions showed a high sensitivity (92.8%) and specificity (83.3%) in detecting MG. QJF showed a powerful action on MG by recovering the holistic serum metabolic profile from the disease level to the normal level. Especially, the levels of GABA, pipecolic acid, ornithine, 5,8-tetradecadienoic acid, spermine, hexanoylcarnitine, N-oleoyl glycine, S1P, bisnorcholic acid, coenzyme Q4, and cholylglycine in MG patients were regulated to a relatively normal level after QJF treatment. / My results first indicated that the LC-FTMS-based metabolomics was a useful tool in biomarkers exploration of MG, and it was potentially applicable as a new diagnostic approach for MG. Also, my results demonstrated that QJF was a good optional choice for the treatment of MG, with no reported side effects. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Lu, Yonghai. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 113-129). / Abstract also in Chinese. / Thesis committee --- p.i / Declaration --- p.ii / Abstract (in English) --- p.iii / Abstract (in Chinese) --- p.vi / Acknowledgements --- p.viii / Table of contents --- p.ix / Abbreviations --- p.xiv / List of Tables --- p.xviii / List of Figures --- p.xix / Chapter 1: Introduction --- p.1 / Chapter 1.1 --- Myasthenia gravis --- p.1 / Chapter 1.1.1 --- History --- p.1 / Chapter 1.1.2 --- Epidemiology --- p.2 / Chapter 1.1.3 --- Clinical features --- p.2 / Chapter 1.1.4 --- Clinical classification --- p.4 / Chapter 1.1.5 --- Pathophysiology --- p.5 / Chapter 1.1.6 --- Diagnosis --- p.9 / Chapter 1.1.6.1 --- Physical examination --- p.9 / Chapter 1.1.6.2 --- Blood test --- p.10 / Chapter 1.1.6.3 --- Electrodiagnostic test --- p.10 / Chapter 1.1.6.4 --- Edrophonium test --- p.11 / Chapter 1.1.6.5 --- Imaging --- p.11 / Chapter 1.1.6.6 --- Pulmonary function test --- p.11 / Chapter 1.1.7 --- Treatment --- p.12 / Chapter 1.1.7.1 --- Medication --- p.12 / Chapter 1.1.7.2 --- Thymectomy --- p.12 / Chapter 1.1.7.3 --- Plasmapheresis and intravenous immunoglobulin --- p.13 / Chapter 1.2 --- Qiangji Jianli Fang --- p.14 / Chapter 1.2.1 --- Huang qi --- p.15 / Chapter 1.2.2 --- Dang shen --- p.16 / Chapter 1.2.3 --- Bai shu --- p.16 / Chapter 1.2.4 --- Dang gui --- p.17 / Chapter 1.2.5 --- Sheng ma --- p.17 / Chapter 1.2.6 --- Chai hu --- p.18 / Chapter 1.2.7 --- Chen pi --- p.18 / Chapter 1.2.8 --- Gan cao --- p.19 / Chapter 1.3 --- Metabolomics --- p.19 / Chapter 1.3.1 --- What’s metabolomics? --- p.20 / Chapter 1.3.1.1 --- Metabolites --- p.20 / Chapter 1.3.1.2 --- Metabolome --- p.21 / Chapter 1.3.1.3 --- Two terms: metabolomics and metabonomics --- p.21 / Chapter 1.3.2 --- How metabolomics works? --- p.22 / Chapter 1.3.2.1 --- Sample preparation --- p.22 / Chapter 1.3.2.1.1 --- Quenching --- p.23 / Chapter 1.3.2.1.2 --- Separating metabolites --- p.24 / Chapter 1.3.2.1.3 --- Sample concentration --- p.24 / Chapter 1.3.2.2 --- Analytical technologies (Sample analysis) --- p.25 / Chapter 1.3.2.3 --- Data analysis --- p.26 / Chapter 1.3.2.4 --- Database --- p.28 / Chapter 1.3.3 --- Why metabolomics? --- p.29 / Chapter 1.3.4 --- Metabolomics for human diseases --- p.30 / Chapter 1.3.5 --- Metabolomics for Traditional Chinese Medicine --- p.32 / Chapter 1.4 --- Objectives and significances of the present study --- p.34 / Chapter Chapter 2 --- Metabolic biomarkers of myasthenia gravis --- p.36 / Chapter 2.1 --- Introduction --- p.36 / Chapter 2.2 --- Materials and methods --- p.40 / Chapter 2.2.1 --- Chemicals --- p.40 / Chapter 2.2.2 --- Patients --- p.40 / Chapter 2.2.3 --- Volunteers --- p.42 / Chapter 2.2.4 --- Blood collection --- p.43 / Chapter 2.2.5 --- QC samples --- p.43 / Chapter 2.2.6 --- Sample processing --- p.43 / Chapter 2.2.7 --- Liquid chromatography-mass spectrometry --- p.44 / Chapter 2.2.8 --- Data analysis --- p.45 / Chapter 2.2.9 --- Metabolite identification --- p.45 / Chapter 2.3 --- Results --- p.46 / Chapter 2.3.1 --- Method validation --- p.46 / Chapter 2.3.2 --- An overall comparative analysis between 28 patients and 10 volunteers --- p.48 / Chapter 2.3.3 --- Classification of MG --- p.53 / Chapter 2.3.4 --- Comparative analysis of the metabolic changes in early- and late-stage MG patients respectively --- p.54 / Chapter 2.3.5 --- Biomarker identification --- p.56 / Chapter 2.4 --- Discussion --- p.58 / Chapter 2.5 --- Conclusion --- p.63 / Chapter Chapter 3 --- A novel diagnostic approach for myasthenia gravis --- p.64 / Chapter 3.1 --- Introduction --- p.64 / Chapter 3.2 --- Materials and methods --- p.68 / Chapter 3.2.1 --- Chemicals --- p.68 / Chapter 3.2.2 --- Patients and Volunteers --- p.69 / Chapter 3.2.2.1 --- Training set for establishment of diagnostic model --- p.69 / Chapter 3.2.2.2 --- Test set for evaluation of diagnostic model --- p.69 / Chapter 3.2.3 --- QC samples --- p.70 / Chapter 3.2.4 --- Sample processing --- p.71 / Chapter 3.2.5 --- Chromatography --- p.71 / Chapter 3.2.6 --- Mass spectrometry --- p.72 / Chapter 3.2.7 --- Data analysis --- p.72 / Chapter 3.3 --- Results --- p.72 / Chapter 3.3.1 --- Method validation --- p.73 / Chapter 3.3.2 --- Alterations in serum metabolic profile under MG --- p.74 / Chapter 3.3.3 --- Prediction of MG based on biomarkers --- p.74 / Chapter 3.3.4 --- Establishment of diagnostic model on the basis of metabolic profile --- p.77 / Chapter 3.3.5 --- Prediction of MG with diagnostic model --- p.79 / Chapter 3.4 --- Discussion --- p.80 / Chapter 3.5 --- Conclusion --- p.83 / Chapter Chapter 4 --- Qiangji Jianli Fang treatment for myasthenia gravis --- p.84 / Chapter 4.1 --- Introduction --- p.84 / Chapter 4.2 --- Materials and methods --- p.88 / Chapter 4.2.1 --- Chemicals --- p.88 / Chapter 4.2.2 --- Herbs --- p.88 / Chapter 4.2.3 --- Participants --- p.88 / Chapter 4.2.4 --- QC samples --- p.90 / Chapter 4.2.5 --- Sample processing --- p.90 / Chapter 4.2.6 --- Liquid chromatography-mass spectrometry --- p.90 / Chapter 4.2.7 --- Data analysis --- p.91 / Chapter 4.3 --- Results --- p.91 / Chapter 4.3.1 --- Method validation --- p.91 / Chapter 4.3.2 --- Symptomatic examination after QJF treatment --- p.92 / Chapter 4.3.3 --- Holistic metabolic responses to QJF treatment --- p.93 / Chapter 4.3.4 --- MG biomarkers changes after QJF treatment --- p.95 / Chapter 4.3.5 --- Drug-related biomarkers of QJF --- p.97 / Chapter 4.4 --- Discussion --- p.100 / Chapter 4.5 --- Conclusion --- p.103 / Chapter Chapter 5 --- Conclusions --- p.104 / Chapter Chapter 6 --- Perspectives --- p.107 / Chapter 6.1 --- Experimental autoimmune myasthenia gravis model --- p.107 / Chapter 6.2 --- Chemical composition of Qiangji Jianli Fang --- p.111 / References --- p.113 / Appendices --- p.130
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Studies on the anti-pancreatic cancer effect of Eriocalyxin B (a diterpenoid isolated from Isodon eriocalyx) and the underlying molecular mechanism in vitro and in vivo.January 2013 (has links)
胰腺癌是一種致死率極高的惡性疾病,在全世界所有的癌症中死亡率排列第八, 在美國排列第四。 很多因素造成了胰腺癌較差的預後,其中包括: 早期檢出率極低; 較少胰腺癌患者的腫瘤適宜手術切除;高轉移率;以及對傳統放療和化療具有較高抗性等。 因此,發展新的治療藥物迫在眉睫。 / 近年來, 植物藥以及從這些植物藥裡分離出的天然化合物, 單獨使用或者與傳統化療藥物合併使用時, 都顯示出對不同類型的癌症具有較好療效。植物藥毛萼香茶菜(唇形科)含有豐富的具有抗癌活性的二萜類化合物。其中毛萼乙素(EriB) 是一個擁有最好抗癌活性的對映-貝殼杉烷型二萜化合物。 基於此背景, 本研究的目標為:利用胰腺癌體外體內模型, 研究EriB的抗胰腺癌活性以及誘導胰腺癌細胞凋亡的機理。 / 體外實驗中, EriB對四種胰腺癌細胞株都顯示了顯著的細胞毒活性,其活性與化療藥物喜樹堿類似。其中, EriB對胰腺癌細胞株CAPAN-2活性最強, 半數致死濃度IC₅₀為0.73 μM。細胞凋亡特徵:細胞核凝聚, 磷脂醯絲氨酸外翻, DNA梯狀條帶以及片斷化,在EriB誘導的胰腺癌細胞株CAPAN-2中出現。此外, EriB還造成癌細胞在細胞週期G2/M期的阻滯。機理研究發現, EriB是通過啟動絲裂原活化蛋白激酶(MAPK), caspase及 p53信號通路來誘導細胞凋亡和細胞週期阻滯的。抗凋亡蛋白與促凋亡蛋白比率(bcl-2/bak)的減少也可能對啟動細胞凋亡內途徑發揮一定作用。除此以外, EriB對癌細胞的細胞毒活性及致凋亡作用依賴于活性氧分子(ROS)的產生。在對細胞進行抗氧化劑預處理的實驗中發現, 只有含巰基基團的抗氧化劑能夠有效的阻斷EriB對癌細胞的活性。進一步實驗證明, EriB對細胞內兩個抗氧化系統: 谷胱甘肽系統及硫氧還蛋白系統的抑制作用導致了ROS在癌細胞中的積聚。同時,ROS的產生啟動了MAPK,熱休克蛋白70以及caspase信號通路,卻抑制了NFκB通路。 / 動物體內實驗證實, 每天對胰腺癌細胞移植瘤裸鼠進行腹腔注射EriB(2.5 毫克/千克),能有效的抑制腫瘤生長, 並且對心臟,肝臟和腎臟沒有引起顯著毒性。 對腫瘤組織的分析表明, 給藥組(EriB)比溶劑對照組出現更多的細胞凋亡, 並產生較多的ROS積聚。 / 綜上所述, 本項研究首次闡述了EriB具有顯著的體內外抗胰腺癌活性。機理研究證明, EriB抑制胰腺癌細胞內兩個含巰基基團的抗氧化系統, 從而導致ROS在細胞中積聚, 並啟動(或抑制)了包括MAPK, p53, caspase和NFB在內的信號通路, 最終導致癌細胞死亡。 此外, 動物體內研究證明EriB的抗腫瘤生長活性和低毒性, 令該化合物具有潛力進一步研究發展成為抗胰腺癌的新藥物。 / Pancreatic cancer is the fourth and eighth leading cause of cancer-related deaths in the U.S. and worldwide, respectively. Its poor prognosis is attributed to its late diagnosis, limitation to surgical resection, aggressive local invasion, and early metastases, as well as high resistance to chemotherapy and radiotherapy. Therefore, a search for an alternative to therapeutic agents is in desperate need. / In recent years, herbal medicines or natural compounds isolated from herbs either used alone or in combination with conventional anti-cancer agents have been shown to have beneficial effects on various cancers. In this context, the Chinese herb Isodon eriocalyx (Dunn.) Hara (family Lamiaceae) is a well-known source of anti-cancer diterpenoids, the most potent one being Eriocalyxin B (EriB, an ent-kauranoid). Therefore, the aims of the present study are to investigate the anti-tumor activities of EriB in human pancreatic adenocarcinoma cells and tumor-bearing mouse model, as well as the underlying mechanisms. / Our results showed that EriB exhibited significant cytotoxic effects on four pancreatic adenocarcinoma cell lines, with potencies being comparable to that of chemotherapeutic agent camptothecin. EriB had the most potent cytotoxicity in CAPAN-2 cells with IC₅₀ = 0.73 μM. The hallmark features of apoptosis, such as nuclear condensation, translocation of phosphatidylserine, DNA laddering, and DNA fragmentation were observed in EriB-treated CAPAN-2 cells. On the other hand, EriB also induced G2/M phase cell cycle arrest. Mechanistic studies revealed that EriB induced apoptosis and cell cycle arrest through the activation of MAPKs (p38, ERK1/2), caspase cascade, and p53/p21/cdk1-cyclinB1 signaling pathways. A decrease in the ratio of anti-apoptotic to pro-apoptotic proteins (bcl-2/bak) also contributed to the activation of intrinsic apoptotic pathway. Further investigation showed that EriB-induced cytotoxic and apoptotic effects were dependent on reactive oxygen species (ROS) production. Such demonstrated effects could be inhibited by pre-treatment with thiol-containing antioxidants. Furthermore, EriB induced ROS was mediated via the inhibition of two main antioxidant systems, namely glutathione and thioredoxin systems. EriB-mediated ROS activated multiple targets or signal pathways, including MAPK, heat shock protein (Hsp) 70, and caspase cascade, while inhibiting the NFκB pathway. / On the other hand, in vivo study demonstrated that daily intraperitoneal administration of EriB (2.5mg/kg/day) in human pancreatic tumor xenografts BALB/c nude mice significantly inhibited tumor growth, but without having toxicity in the heart, liver and kidney. In addition, EriB treatments induced in vivo cell apoptosis and superoxide production as observed in tumor tissues. / In conclusion, the present study reports for the first time that EriB has possessed anti-proliferative activities in pancreatic cancer cells. The anti-proliferative effects of EriB on CAPAN-2 cells could be attributable to the regulation of cellular apoptosis and cell cycle arrest. The inhibitory effects of EriB on two antioxidant systems result in the accumulation of ROS, which in turn activate MAPK, p53, Hsp70 and caspase cascade, while inhibiting NFB pathway and finally leading to pancreatic cancer cell death. Meanwhile, in vivo study further confirms the anti-tumor properties of EriB, suggesting that EriB could be considered as a potential chemotherapeutic agent for patients with pancreatic cancer. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Li, Lin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 207-230). / Abstracts also in Chinese. / Abstract (English) --- p.i / Abstract (Chinese) --- p.iv / Publications --- p.vi / Acknowledgements --- p.vii / Table of contents --- p.ix / List of figures --- p.xv / List of tables --- p.xix / List of abbreviations --- p.xx / Chapter Chapter1 --- General Introduction --- p.1 / Chapter 1.1 --- The pancreas --- p.2 / Chapter 1.1.1 --- Anatomy of the pancreas --- p.2 / Chapter 1.1.2 --- Histology of the pancreas --- p.4 / Chapter 1.1.3 --- Exocrine pancreas --- p.5 / Chapter 1.1.3.1 --- Structure of secretory acini, ducts and stroma in pancreas --- p.5 / Chapter 1.1.3.2 --- Functions of exocrine pancreas --- p.6 / Chapter 1.1.4 --- Endocrine pancreas --- p.9 / Chapter 1.1.4.1 --- Structure of islets cells --- p.10 / Chapter 1.1.4.2 --- Functions of endocrine pancreas --- p.10 / Chapter 1.1.5 --- Disorders of the pancreas --- p.11 / Chapter 1.2 --- Pancreatic cancer --- p.14 / Chapter 1.2.1 --- Epidemiology --- p.14 / Chapter 1.2.2 --- The risks and causes of pancreatic cancer --- p.15 / Chapter 1.2.3 --- Signs and symptoms of pancreatic cancer --- p.18 / Chapter 1.2.4 --- Types of pancreatic cancer --- p.19 / Chapter 1.2.5 --- Diagnosis of pancreatic cancer --- p.21 / Chapter 1.2.6 --- Staging of pancreatic cancer --- p.27 / Chapter 1.3 --- Treatments for pancreatic cancer --- p.29 / Chapter 1.3.1 --- Surgery --- p.29 / Chapter 1.3.2 --- Chemotherapy --- p.30 / Chapter 1.3.2.1 --- 5-fluorouracil (5-FU) --- p.32 / Chapter 1.3.2.2 --- Gemcitabine (Gem) --- p.33 / Chapter 1.3.2.3 --- Other cytotoxic agents --- p.34 / Chapter 1.3.3 --- Radiotherapy --- p.35 / Chapter 1.3.4 --- Target therapies --- p.37 / Chapter 1.3.4.1 --- Antiangiogenic therapy --- p.37 / Chapter 1.3.4.2 --- Epidermal growth factor receptor (EGFR) signaling inhibitors --- p.39 / Chapter 1.3.4.3 --- Hedgehog and Notch signaling pathways inhibitors --- p.41 / Chapter 1.3.5 --- Gene therapy --- p.42 / Chapter 1.3.6 --- Immunotherapy --- p.45 / Chapter 1.3.7 --- Combination therapies --- p.46 / Chapter 1.4 --- Molecular targets for pancreatic cancer chemotherapy --- p.49 / Chapter 1.4.1 --- Therapies-induced apoptosis --- p.49 / Chapter 1.4.1.1 --- Caspase cascade and bcl-2 Family --- p.49 / Chapter 1.4.1.2 --- Role of mitogen-activated protein kinases (MAPKs) in apoptosis --- p.50 / Chapter 1.4.2 --- Nuclear factor-κB activation in pancreatic cancer --- p.50 / Chapter 1.4.3 --- The PI3K and AKT pathway --- p.51 / Chapter 1.4.4 --- JAK/STAT pathway --- p.51 / Chapter 1.4.5 --- Other molecular targets --- p.52 / Chapter 1.5 --- Herbal medicine as an alternative treatment for cancer treatment --- p.53 / Chapter 1.5.1 --- Herbal medicines for different types of cancer treatment --- p.53 / Chapter 1.5.2 --- Herbal medicines for pancreatic cancer treatment --- p.59 / Chapter 1.6 --- Introduction of Isodon eriocalyx (Dunn.) Hara --- p.61 / Chapter 1.6.1 --- Background of Isodon genus and Isodon eriocalyx (Dunn.) Hara --- p.61 / Chapter 1.6.2 --- Diterpenoids from Isodon species and their activities --- p.62 / Chapter 1.6.3 --- The potential anti-cancer activity of Eriocalyxin B, a diterpenoid isolated from Isodon eriocalyx (Dunn.) Hara --- p.62 / Chapter 1.7 --- Aims and objectives of this study --- p.66 / Chapter Chapter 2 --- Eriocalyxin B induces apoptosis and cell cycle arrest in pancreatic adenocarcinoma cells through caspase- and p53-dependent pathways --- p.67 / Chapter 2.1 --- Introduction --- p.68 / Chapter 2.2 --- Materials and methods --- p.71 / Chapter 2.2.1 --- Preparation and quality control of Eriocalyxin B --- p.71 / Chapter 2.2.2 --- Materials --- p.72 / Chapter 2.2.3 --- Cell culture --- p.72 / Chapter 2.2.4 --- Preparation of human peripheral blood mononuclear cells (PBMC) --- p.73 / Chapter 2.2.5 --- Cytotoxicity assay --- p.75 / Chapter 2.2.6 --- Hoechst 33258 staining for morphological evaluation --- p.76 / Chapter 2.2.7 --- DNA fragmentation detection by DNA ladder --- p.76 / Chapter 2.2.8 --- Cell death detection ELISA --- p.77 / Chapter 2.2.9 --- Apoptosis detection by flow cytometry --- p.78 / Chapter 2.2.10 --- Cell cycle analysis by flow cytometry --- p.78 / Chapter 2.2.11 --- Western blot analysis --- p.79 / Chapter 2.2.12 --- Statistical analysis --- p.80 / Chapter 2.3 --- Results --- p.81 / Chapter 2.3.1 --- EriB induces cytotoxic effect in human pancreatic cancer cells --- p.81 / Chapter 2.3.2 --- EriB induces apoptosis in CAPAN-2 cells --- p.85 / Chapter 2.3.3 --- Activation of pro-apoptotic caspases in EriB-treated CAPAN-2 cells --- p.89 / Chapter 2.3.4 --- Modulation of bcl-2/bak ratio in EriB-treated CAPAN-2 cells --- p.92 / Chapter 2.3.5 --- EriB causes G2/M cell cycle arrest --- p.94 / Chapter 2.3.6 --- EriB modulates expression of G2/M cell cycle regulatory proteins through activation of the p53 pathway --- p.96 / Chapter 2.4 --- Discussion --- p.99 / Chapter Chapter 3 --- Eriocalyxin B induces apoptosis in pancreatic cancer CAPAN-2 cells via mediation of reactive oxygen species --- p.107 / Chapter 3.1 --- Introduction --- p.108 / Chapter 3.2 --- Materials and methods --- p.113 / Chapter 3.2.1 --- Materials --- p.113 / Chapter 3.2.2 --- Cell culture and MTT assay --- p.113 / Chapter 3.2.3 --- Apoptosis detection by flow cytometry --- p.114 / Chapter 3.2.4 --- Reactive oxygen species (ROS) detection by flow cytometry --- p.114 / Chapter 3.2.5 --- Glutathione assessment --- p.115 / Chapter 3.2.6 --- Glutathione peroxidase (GPx) activity detection --- p.116 / Chapter 3.2.7 --- Thioredoxin reductase (TrxR) activity detection --- p.116 / Chapter 3.2.8 --- Nuclear and cytosolic fractionation --- p.117 / Chapter 3.2.9 --- Western blot analysis --- p.117 / Chapter 3.2.10 --- Electrophoretic mobility shift assay --- p.119 / Chapter 3.2.11 --- Statistical analysis --- p.119 / Chapter 3.3 --- Results --- p.120 / Chapter 3.3.1 --- Thiol-containing antioxidants inhibits EriB-induced cytotoxic effects --- p.120 / Chapter 3.3.2 --- Thiol-containing antioxidants inhibits EriB-induced apoptotic effects --- p.122 / Chapter 3.3.3 --- Effects of EriB on hydrogen peroxide production --- p.125 / Chapter 3.3.4 --- EriB depletes glutathione level and suppresses GPx activity --- p.128 / Chapter 3.3.5 --- EriB inhibits thioredoxin system and activates ASK1 --- p.130 / Chapter 3.3.6 --- EriB increases Hsp70 and cleaved-PARP expression through ROS --- p.134 / Chapter 3.3.7 --- EriB inhibits NFkB pathway in CAPAN-2 cells --- p.137 / Chapter 3.4 --- Discussion --- p.142 / Chapter Chapter 4 --- In vivo study of the anti-tumor efficacy of Eriocalyxin B in human pancreatic tumor xenograft model --- p.149 / Chapter 4.1 --- Introduction --- p.150 / Chapter 4.2 --- Materials and methods --- p.154 / Chapter 4.2.1 --- Establishment of a subcutaneous pancreatic cancer xenograft model --- p.154 / Chapter 4.2.2 --- Evaluation of the effects of EriB on tumor growth --- p.155 / Chapter 4.2.2.1 --- Pilot study for EriB and camptothecin treatment --- p.155 / Chapter 4.2.2.2 --- Confirmation study of effective dose of EriB --- p.156 / Chapter 4.2.2.3 --- Dose-comparison study of CPT-11 --- p.156 / Chapter 4.2.2.4 --- Comparison study of EriB and CPT-11 treatments --- p..157 / Chapter 4.2.3 --- Measurement of plasma-specific enzyme levels --- p.157 / Chapter 4.2.4 --- Assays of terminal deoxytransferase-catalyzed DNA nick-end labeling (TUNEL) --- p..158 / Chapter 4.2.5 --- Histological evaluation --- p.159 / Chapter 4.2.6 --- Detection of superoxide by DHE staining --- p.159 / Chapter 4.2.7 --- Establishment of an orthotopic model (SW1990) of pancreatic cancer and detection of the plasma biomarker CA19-9 --- p.160 / Chapter 4.2.7.1 --- Detection of CA19-9 expression by immunofluorescent staining and western blot --- p.161 / Chapter 4.2.7.2 --- Establishment of an orthotopic pancreatic cancer xenograft model by SW1990 cells --- p.162 / Chapter 4.2.8 --- Statistical analysis --- p.164 / Chapter 4.3 --- Results --- p.165 / Chapter 4.3.1 --- EriB inhibits the growth of CAPAN-2 human pancreatic tumor xenografts --- p.165 / Chapter 4.3.2 --- EriB treatments induce cell apoptosis in tumor tissues --- p.173 / Chapter 4.3.3 --- Toxicity tests for EriB --- p.175 / Chapter 4.3.3.1 --- Plasma enzyme levels after EriB treatments --- p.175 / Chapter 4.3.3.2 --- No apparent alterations in histology of the heart, liver and kidney tissues --- p..176 / Chapter 4.3.4tEriB induces superoxide production in the tumor tissues --- p.178 / Chapter 4.3.5 --- Successful establishment of an orthotopic xenograft model --- p.180 / Chapter 4.4 --- Discussion --- p.184 / Chapter Chapter 5 --- General Discussion --- p.188 / Chapter 5.1 --- Discussion --- p.189 / Chapter 5.2 --- Conclusion --- p.204 / Chapter 5.3 --- Limitations of the study --- p.205 / Chapter 5.4 --- Future work --- p.206 / Chapter Chapter 6 --- References --- p.207
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Molecular authentication and phylogenetic studies of Chinese herbs.January 2009 (has links)
Wang, Yanli. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 90-104). / In English with some Chinese characters; abstract also in Chinese. / Acknowledgement --- p.I / Abstract --- p.III / 摘要 --- p.V / Table of Content --- p.VII / List of Figures --- p.XIII / List of Tables --- p.XV / Abbreviations --- p.XVI / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1. --- Traditional Chinese Medicine (TCM) --- p.1 / Chapter 1.2. --- The development history and present situation of Traditional Chinese Medicine --- p.2 / Chapter 1.3. --- Modernization of Traditional Chinese Medicine --- p.3 / Chapter 1.4. --- Authentication of Traditional Chinese Medicines --- p.4 / Chapter 1.5. --- Methods for authentication of Traditional Chinese Medicine --- p.5 / Chapter 1.5.1. --- Morphological and histological methods --- p.5 / Chapter 1.5.2. --- Chemical methods --- p.6 / Chapter 1.5.3. --- Molecular methods --- p.6 / Chapter 1.6. --- DNA regions suitable for molecular authentication of Traditional Chinese Medicine --- p.8 / Chapter 1.6.1. --- The chloroplast genome --- p.8 / Chapter 1.6.2. --- Nuclear sequences --- p.9 / Chapter 1.6.3. --- Mitochondrial genome --- p.12 / Chapter 1.7. --- Herb Tu Si Zi --- p.12 / Chapter 1.7.1. --- The identity of Traditional Chinese Medicine Tu Si Zi --- p.12 / Chapter 1.7.2. --- The medicinal values of Tu Si Zi --- p.13 / Chapter 1.7.3. --- Local substitutes of Tu Si Zi --- p.14 / Chapter 1.7.4. --- The need for molecular authentication of Tu Si Zi --- p.15 / Chapter 1.8. --- Traditional Chinese Medicinal herbs from Isodon --- p.15 / Chapter 1.8.1. --- The genus Isodon --- p.15 / Chapter 1.8.2. --- Xi Huang Cao --- p.16 / Chapter 1.8.2.1. --- Identity of Xi Huang Cao --- p.16 / Chapter 1.8.2.2. --- Medicinal values of Xi Huang Cao --- p.17 / Chapter 1.8.2.3. --- Confusions of herb Xi Huang Cao --- p.17 / Chapter 1.8.3. --- Dong Ling Cao --- p.18 / Chapter 1.8.3.1. --- Identity of Dong Ling Cao --- p.18 / Chapter 1.8.3.2. --- Medicinal values of Dong Ling Cao --- p.18 / Chapter 1.8.4. --- The molecular authentication of two Isodon herbs --- p.19 / Chapter 1.9. --- Fagaropsis and Luvunga --- p.20 / Chapter 1.9.1. --- The classification of Rutaceae --- p.20 / Chapter 1.9.2. --- Controversial taxonomic issues with Fagaropsis and Luvunga --- p.21 / Chapter 1.9.3. --- The need of phylogenetic studies of genus Fagaropsis and Luvunga --- p.23 / Chapter Chapter 2. --- Objectives --- p.24 / Chapter Chapter 3. --- Materials and Methods --- p.25 / Chapter 3.1. --- Samples used in this study --- p.25 / Chapter 3.1.1. --- Tu Si Zi (Dodder seeds) --- p.25 / Chapter 3.1.2. --- Isodon herbs --- p.28 / Chapter 3.1.3. --- Fagaropsis and Luvunga --- p.31 / Chapter 3.2. --- Methods --- p.34 / Chapter 3.2.1. --- Sample preparation --- p.34 / Chapter 3.2.2. --- Total DNA extraction --- p.34 / Chapter 3.2.2.1. --- Cetyltriethylammonium bromide extraction --- p.34 / Chapter 3.2.2.2. --- Commercial kit extraction --- p.36 / Chapter 3.2.3. --- DNA amplification --- p.38 / Chapter 3.2.3.1. --- psbA-trnH intergenic spacer --- p.39 / Chapter 3.2.3.2. --- trnL-trnF region --- p.39 / Chapter 3.2.3.3. --- ITS region --- p.42 / Chapter 3.2.4. --- Agarose gel electrophoresis --- p.43 / Chapter 3.2.5. --- Purification of PCR product --- p.44 / Chapter 3.2.6. --- Cloning --- p.46 / Chapter 3.2.6.1. --- Ligation --- p.46 / Chapter 3.2.6.2. --- Transformation --- p.46 / Chapter 3.2.6.3. --- Cell cultivation --- p.47 / Chapter 3.2.6.4. --- Plasmid extraction --- p.47 / Chapter 3.2.6.5. --- Insert confirmation --- p.49 / Chapter 3.2.7. --- DNA sequencing --- p.49 / Chapter 3.2.7.1. --- Cycle sequencing --- p.49 / Chapter 3.2.7.2. --- Purification of cycle sequencing product --- p.50 / Chapter 3.2.7.3. --- DNA analysis --- p.50 / Chapter 3.2.8. --- Sequence analysis and phylogeny construction --- p.51 / Chapter Chapter 4. --- Tu Si Zi (Dodder Seeds) - Results and Discussion --- p.52 / Chapter 4.1. --- Results --- p.52 / Chapter 4.1.1. --- Dendrogram constructed using psbA-trnH intergenic spacer --- p.52 / Chapter 4.1.2. --- Dendrogram constructed using trnL-trnF region --- p.53 / Chapter 4.1.3. --- Dendrogram constructed with the combination of psbA-trnH and trnL-trnF region --- p.59 / Chapter 4.2 --- Discussion --- p.60 / Chapter 4.2.1. --- Identification of DNA markers for Cuscuta species --- p.60 / Chapter 4.2.2. --- Molecular authentication of dodder seeds --- p.60 / Chapter Chapter 5. --- Isodon herbs - Results and Discussion --- p.64 / Chapter 5.1. --- Results --- p.64 / Chapter 5.1.1. --- Dendrogram constructed with internal transcribed spacer 1 --- p.64 / Chapter 5.1.2. --- Dendrogram established with internal transcribed spacer 2 --- p.65 / Chapter 5.1.3. --- Dendrogram established with the whole internal transcribed spacer region --- p.66 / Chapter 5.2. --- Discussion --- p.73 / Chapter 5.2.1. --- ITS region performing as DNA marker for Dong Ling Cao --- p.73 / Chapter 5.2.2. --- The identify of TCM materials of Xi Huang Cao --- p.73 / Chapter Chapter 6. --- Fagaropsis and Luvunga - Results and Discussion --- p.75 / Chapter 6.1. --- Results --- p.75 / Chapter 6.1.1. --- Phylogenetic tree constructed with internal transcribed spacer 1 --- p.76 / Chapter 6.1.2. --- Phylogenetic tree constructed with trnL-trnF region --- p.76 / Chapter 6.1.3. --- Phylogenetic tree constructed with combined of trnL-trnF region and ITS-1 region --- p.77 / Chapter 6.1.4. --- The location of Fagaropsis and Luvunga in 3 different phylogenetic trees --- p.78 / Chapter 6.2. --- Discussion --- p.85 / Chapter 6.2.1. --- Fagaropsis 一 a member of the ´بProto-Rutaceae´ة group --- p.85 / Chapter 6.2.2. --- Luvunga 一 a member of Aurantioideae --- p.86 / Chapter 6.2.3. --- DNA sequencing providing a useful methodology in plant phylogenetic studies --- p.87 / Chapter Chapter 7. --- Conclusions --- p.89 / References --- p.90 / Appendix 1. Sequence alignment ofpsbA-trnH intergenic spacer of dodder --- p.105 / Appendix 2. Sequence alignment of trnL-trnF region of dodder samples --- p.108 / Appendix 3. Sequence alignment of ITS region of Isodon herbs and specimens --- p.117 / Appendix 4. Sequence alignment of ITS-1 region of Rutaceae species --- p.124 / Appendix 5. Sequence alignment of trnL-trnF region of Rutaceae species --- p.129
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Micropropagation of Brunsvigia undulata F.M. Leight.Rice, Laura Jane. January 2009 (has links)
Many South African medicinal plants face the threat of over-collection for use in traditional medicines. Many bulbous plants suffer as the whole plant is removed from the wild so that the bulb may be used for medicine. Micropropagation is a technique which can be used as an alternative to conventional propagation methods. Micropropagation produces many plantlets in a relatively short period of time. Different plant parts of Brunsvigia undulata F.M. Leight, a rare South African species of medicinal value, were used in an attempt to produce in vitro plantlets using micropropagation techniques. Although leaf and floral explants were successfully formed from seedling explants and twin-scales. Seeds germinated quickly in culture. Seedlings which grew from seeds were cut into sections and used to initiate bulblets. Seedling explants formed bulblets, shoots and callus best when the explants included a meristematic region. Callus from seedling explants formed shoot clusters readily when placed on hormone-free MURASHIGE and SKOOG (1962) (MS) medium. Shoots from shoot clusters formed bulblets and rooted on medium supplemented with IBA. The greatest rooting response was achieved by bulblets on 1 mgl-1 IBA. The callus which was left after shoot clusters were separated was placed back onto hormone-free MS medium. Callus explants continued to form shoot clusters. Twin-scales, cut from large parent bulbs, were cultured on 25 hormone treatments. Bulblets formed on twin-scales even in the absence of plant growth hormones. Bulblets formed by twin-scales were used to determine the effects of both medium constituents and environmental factors on bulblet multiplication. Bulblet multiplication was greatest when bulblets were split in half and cultured as half-bulblets. Optimal multiplication was achieved on hormone-free MS, with 4% sucrose, kept at high temperatures in the dark. Bulblets were successfully initiated and multiplied from both seedlings and twin-scales. Bulblets which were produced via both protocols were acclimatized relatively easily. Both explant types could be used to mass propagate Brunsvigia undulata. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
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Micropropagation and secondary metabolites of Sclerocarya birrea.Moyo, Mack. January 2009 (has links)
Sclerocarya birrea (marula, Anacardiaceae) is a highly-valued indigenous tree in most parts of sub-Saharan Africa because of its medicinal and nutritional properties. The marula tree is adapted to the semi-arid conditions that characterise most parts of sub-Saharan Africa and renders them unsuitable for conventional crop agriculture. The unique nutritional properties of marula and its high tolerance to dry conditions provide opportunities for its development into a plantation crop. On the other hand, the demand for marula plant parts, mainly the bark and roots as medicinal remedies, poses a great threat to wild populations. In the long term, the growing demand of marula products in the food, pharmaceutical and cosmetic industries will not be sustainable from wild populations alone. Plant tissue culture technologies can be useful for in vitro manipulation and mass propagation of the plant in the process of domestication and conservation. The aims of the project were to determine the optimum conditions for seed germination, in vitro propagation and plant regeneration, and to evaluate the potential bioactivity of secondary metabolites from its renewable plant parts as an alternative option in the conservation of S. birrea.
An ex vitro seed germination study indicated that after-ripening and cold stratification are critical factors. Cold stratification (5 °C) of marula nuts for 14 days improved germination (65%) as compared to non-stratified nuts (32%). Direct shoot organogenesis was achieved from leaf explants through the induction of nodular meristemoids on Murashige and Skoog (MS) (1962) medium and woody plant medium (WPM) supplemented with 6-benzyladenine (BA) in combination with naphthalene acetic acid (NAA), indole-3-butryric acid (IBA) and indole-3-acetic acid (IAA). Induction of nodular meristemoids from 86% of the leaf cultures was achieved on a MS medium with 4.0 ìM BA and 1.0 ìM NAA. High levels (78–100%) of induction were also achieved on WPM with different concentrations of BA (1.0–4.0 ìM) and IBA (1.0–4.0 ìM). The highest conversion of nodular meristemoids into shoots on MS initiation medium was only 22% for 4.0 ìM BA and 1.0 ìM NAA. This was improved to 62% when nodular clusters were cultured in MS liquid medium. Histological studies revealed high numbers of unipolar meristematic buds developing from globular nodules. These embryo-like structures have in the past been mistaken for true somatic embryos. The initiation of high numbers of nodular meristemoids per explant provides potential for automated large-scale clonal propagation in bioreactors, in vitro phytochemical production and the development of synthetic seed technology, similar to somatic embryogenesis. Plant regeneration through nodule culture has potential for application in mass micropropagation and plant breeding of S. birrea.
Adventitious shoot and root induction are important phases in micropropagation. Plant growth regulators play an important role in these developmental processes, and the type and concentration used have major influences on the eventual organogenic pathway. Three auxins (IAA, IBA and NAA) and four aromatic cytokinins (6-benzyladenine, meta-topolin, meta-topolin riboside, and meta-methoxytopolin riboside) were evaluated for their potential to induce adventitious shoot and root formation in S. birrea shoots, hypocotyls and epicotyls. Among the evaluated cytokinins, the highest adventitious shoot induction (62%) was achieved on MS medium supplemented with meta-topolin (8.0 ìM). The lowest adventitious shoot induction (2.5%) was obtained on MS basal medium containing 2.0 ìM meta-methoxytopolin riboside. The highest adventitious shoot induction for hypocotyls was 55% on MS medium supplemented with 8.0 ìM meta-topolin. For the tested auxins, IBA induced adventitious rooting in 91% of shoots at a concentration of 4.0 ìM after 8 weeks in culture. However, the in vitro rooted plants only survived for two weeks when transferred ex vitro. A temperature of 25 °C and 16-h photoperiod were optimum for adventitious root induction. Stomatal density (number per mm2) on the abaxial leaf surfaces was higher for the 16-h photoperiod treatment (206.6 ± 15.28) compared to that for a 24-h photoperiod (134.6 ± 12.98). Normal mature stomata with kidney-shaped guard cells and an outer ledge over the stomatal pore were observed for in vitro plants growing under a 16-h photoperiod.
Total phenolic content, proanthocyanidins, gallotannins, flavonoids, and antioxidant activities of S. birrea methanolic extracts were evaluated using in vitro bioassays.
Methanolic extracts of the young stem bark and leaves contained high levels of these phytochemicals. Sclerocarya birrea young stem extracts contained the highest levels of total phenolics (14.15 ± 0.03 mg GAE g-1), flavonoids (1219.39 ± 16.62 ìg CE g-1) and gallotannins (246.12 ± 3.76 ìg GAE g-1). Sclerocarya birrea leaf extracts had the highest concentration of proanthocyanidins (1.25%). The EC50 values of the extracts in the DPPH free radical scavenging assay ranged from 5.028 to 6.921 ìg ml-1, compared to ascorbic acid (6.868 ìg ml-1). A dose-dependent linear curve was obtained for all extracts in the ferric-reducing power assay. All the extracts exhibited high antioxidant activity comparable to butylated hydroxytoluene based on the rate of â-carotene bleaching (89.6 to 93.9%). Sclerocarya birrea provides a source of secondary metabolites which have potent antioxidant properties and may be beneficial to the health of consumers.
Sclerocarya birrea young stem and leaf ethanolic extracts exhibited high bioactivity (MIC < 1.0 mg ml-1) against both Gram-positive (Bacillus subtilis and Staphylococcus aureus) and Gram-negative (Escherichia coli and Klebsiella pneumoniae) bacteria. The highest activity (MIC = 0.098 mg ml-1 and total activity = 1609.1 ml g-1) was recorded for young stem extracts against B. subtilis. The highest activity (MIC = 1.56 mg ml-1 and MFC = 1.56 mg ml-1) in the antifungal assay against Candida albicans was observed for young stem ethanolic extracts. Sclerocarya birrea extracts had moderate acetylcholinesterase (AChE) inhibition activity. The dichloromethane (DCM) and methanol (MeOH) fractions exhibited dose-dependent acetylcholinesterase inhibitory activity. The highest AChE inhibitory activities were from leaves (DCM fraction, IC50 = 0.1053 mg ml-1) and young stems (MeOH fraction, IC50 = 0.478 mg ml-1). High inhibitory activity against cyclooxygenase (COX-1 and COX-2) enzymes was observed. All extracts and fractions showed high COX-1 enzyme inhibition (90.7-100%). Petroleum ether (PE) and dichloromethane fractions also exhibited high inhibition against COX-2 enzyme (77.7-92.6%). The pharmacological activities observed suggest that S. birrea renewable plant parts (leaves and young stems) provide a substantial source of medicinal secondary metabolites. Based on these results, plant part substitution can be a practical conservation strategy for this species. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
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Micropropagation and medicinal properties of Barleria greenii and Huernia hystrix.January 2009 (has links)
The crisis of newly emerging diseases and the resistance of many pathogens to currently used drugs, coupled with the adverse side-effects of many of these drugs have necessitated the continuous search for new drugs that are potent and efficacious with minimal or no adverse side-effects. The plant kingdom is known to contain many novel biologically active compounds, many of which could potentially have a higher medicinal value when compared to some of the current medications. Indeed, the use of plants in traditional medicine, especially in African communities, is gaining more importance due to their affordability and accessibility as well as their effectiveness. Exponential population growth rates in many developing countries has resulted in heavy exploitation of our plant resources for their medicinal values. In addition, plant habitat destruction arising from human developmental activities has contributed to the fragmentation or loss of many plant populations. Owing to these factors, many plant species with horticultural and/or medicinal potential have become either extinct or are threatened with extinction. These threatened species cut across different taxonomic categories including shrubs, trees and succulents. Without the application of effective conservation strategies, the medicinal and/or horticultural potential of such threatened species may be totally lost with time. The extinction of such species could lead to the loss of potential therapeutic compounds and/or genes capable of being exploited in the biosynthesis of new potent pharmaceutical compounds. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
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Seed germination and medicinal properties of Alepidea species.Mulaudzi, Rofhiwa Bridget. January 2009 (has links)
The rhizomes of Alepidea amatymbica and Alepidea natalensis are used for medicinal purposes. Because of the increase in demand for these plants the species is becoming scarce. As the seed biology of neither species is well defined, conditions as well as treatments required for optimum germination and vigour were studied. Seeds were exposed to various physical factors such as varying light and temperature conditions and cold stratification, sowing depth and seed storage. The effects of smoke-water, butenolide (3-methyl-2H-furo [2, 3-c] pyran-2-one) a novel smoke compound and chemical substances (gibberellins, kinetin and KNO3) were also tested in order to improve seed germination. Alepidea amatymbica and A. natalensis achieved the highest seed germination (72.5% and 80%, respectively) at 25 °C under a 16 h photoperiod with a mean germination time (MGT) of 18 and 12 days, respectively. Phytochrome studies showed that A. natalensis requires light for germination. Cold stratification (5 °C) for 14-28 days significantly improved the percentage germination of both species (> 90%) compared to non-stratified seeds (control) at 25 °C under a 16 h photoperiod. Sowing A. amatymbica and A. natalensis seeds at a depth of 0.5 cm resulted in higher percentage germination compared to 2.5 cm. The highest emergence rate for A. amatymbica was 40% at a sowing depth of 0.5 cm and the lowest emergence rate was 3% at 2.5 cm. Six months storage of A. natalensis seeds at room temperature (25 ± 2 °C) showed maximum germination (99%) with a MGT of 9 days. Smoke-water treatment of A. amatymbica seeds significantly enhanced germination from 72% to 91%. Smoke and butenolide at 10 °C and 25 °C promoted germination of A. natalensis seeds in a 16 h photoperiod. Smokewater application significantly improved both germination and seedling vigour of A. natalensis. GA3 (10-8 M) was the best treatment for achieving maximum percentage germination of A. natalensis seeds. Antibacterial (two Gram-positive bacteria: Bacillus subtilis, Staphylococcus aureus and two Gram-negative bacteria: Escherichia coli, Klebsiella pneumoniae), antifungal (Candida albicans), anti-inflammatory (COX-1 and -2) and genotoxicity tests (Ames test) were carried out on petroleum ether (PE), dichloromethane (DCM), 80% ethanol (EtOH) and water extracts of the two Alepidea species. Water extracts of A. natalensis rhizomes exhibited high activity (MIC values of 0.78 mg/ml) against the four bacterial strains. High activity was also observed in the PE and DCM leaf extracts of the same plant against the Gram-positive bacteria. The PE and DCM extracts of A. amatymbica rhizomes exhibited the best activity (MIC values of 0.39 mg/ml) against Bacillus subtilis. The rest of the extracts showed low activity (MIC values >1 mg/ml). All the extracts showed activity against Candida albicans, with A. natalensis leaf extracts exhibiting the highest antifungal activity with MIC values of 0.88, 0.20 and 0.78 mg/ml for PE, DCM and EtOH, respectively. EtOH extracts had inhibition less than 40% for both A. natalensis and A. amatymbica. All the PE extracts showed higher inhibitory activity for COX-2 than for COX-1. PE and DCM extracts had percentage inhibitions above 70% in both COX-1 and COX-2 assays. The Ames test for genotoxicity revealed that none of the plant extracts were genotoxic to the Salmonella TA98 tester strain. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
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Pharmacology and phytochemistry of South African plants used as anthelmintics.Aremu, Adeyemi Oladapo. January 2009 (has links)
Traditional medicine in South Africa is part of the culture of the people and has been in existence for a long-time. Although animal components form part of the ingredients used, plant material constitutes the major component. South Africa is endowed with vast resources of medicinal and aromatic plants which have been employed for treatment against various diseases for decades. A large number of South Africans still depend on traditional medicine for their healthcare needs due to its affordability, accessibility and cultural importance. Helminth infections are among the variety of diseases treated by traditional healers. These infections are regarded as neglected tropical diseases (NTDs) due to their high prevalence among the economically disadvantaged living in rural areas in different regions of the world. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
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A Política nacional de plantas medicinais e fitoterápicos : um estudo a partir da análise de políticas públicasCzermainski, Silvia Beatriz Costa January 2009 (has links)
Este trabalho é o resultado de uma pesquisa exploratória por meio de metodologia qualitativa, de análise documental, da Política Nacional de Plantas Medicinais e Fitoterápicos com base no modelo dos Fluxos Múltiplos de John Kingdon para análise de políticas públicas. Foi efetuada revisão dos modelos de análises de políticas públicas e analisados os antecedentes da formação da agenda das políticas públicas farmacêuticas e o processo de formação da agenda e formulação da Política referida. Foram identificados os atores envolvidos, os conceitos, os problemas e as soluções apresentados, o fluxo político que as colocou na agenda governamental e seu processo de formulação, assim como os empreendedores e a ocorrência de janelas de oportunidades. E assim objetivando avaliar as possibilidades de sua implementação em relação as suas diretrizes de desenvolvimento científico e tecnológico no estado do Rio Grande do Sul, as dicotomias e ambigüidades presentes no processo. A partir da análise discutiram-se aspectos a superar e aperfeiçoar a fim de que sejam alcançados seus propósitos. / This work is the result of a exploratory research, by qualitative methodology, documental analysis, of National Policy of Medicinal Plants and Phytomedicines, based on Multiple Streams Model, by John Kingdon, for public policies analyses. It was made a review of policy analysis models and analyzed the preceding facts of agenda setting of pharmaceuticals public policies and the agenda setting and formulation process of the policy. The actors involved, the concepts, the problems and solutions presented, the political stream of governmental agenda and its formulation process, also the policy entrepreneurs, and policy windows. So, evaluating the possibilities of its implementation, relative to the scientific and technological development in the state of Rio Grande do Sul, the dichotomies and ambiguities in the process. To assume that analysis, we discussed aspects to overcome and improve with the intention to reach their purposes.
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Effects of micronutrients on growth and quality of bush tea (Athrixia phylicoides DC)Maedza, Khathutshelo Vuwani 20 April 2016 (has links)
Bush tea (Athrixia phylicoides DC.) is a herbal beverage and medicinal plant indigenous to South Africa. A trial was conducted to determine the effect of micronutrients on the plant growth and quality of bush tea. The trial was laid out in a completely randomized block design with five replicates. Treatments consisted of single applications of Zinc (Zn), Copper (Cu), Boron (Bo), Iron (Fe) and Magnesium (Mg) at three levels (50ml/l, 100ml/l and 150ml/l) and a combination of all micronutrients. A control treatment with no spray was also included. Leaf analysis was conducted using Varian Liberty series II instrument. Total polyphenols were determined using the Folin Ciocalteau method and tannins were determined using Vanillin HCl method. Bush tea samples (one leaf per sample) were analysed using head space solid phase micro-extraction gas chromatography (HS-SPME-GC-MS).
Results of this study demonstrated that application of micronutrients increased the total polyphenols, tannins and total flavonoids in bush tea, with most of the increase in total polyphenols (77.5-93.7 mg/g) occurring in combination B + Zn + Fe + Cu + Mg treatment, increase in tannins (87.3-99.5 mg/g) occurring in copper treatment and increase in total flavonoids (164.6-176.6 mg/g) occurring in mixture (B + Zn + Fe + Cu + Mg) treatment.
Results also show a significant increase in the quality and plant growth of bush tea. Five major compounds were identified (>80% identification probability) namely alpha-pinene, beta-pinene, myrcene, beta-caryophyllene and caryophyllene oxide. Linear relationship between percentage leaf tissues and treatments levels of micronutrients in bush tea was also observed. Boron and copper treatments showed strong linear correlation with a positive relationship between treatments levels and leaf percentage. Therefore, for improved total polyphenols content in bush tea leaves, a combination of (B + Zn + Fe + Cu + Mg) is recommended. Tannin content in bush tea leaves were significantly increased at Cu50 ml/l, Cu100 ml/l and Cu150 ml/l. For improved total flavonoids content in bush tea leaves, a combination of foliar spray of (B + Zn + Fe + Cu + Mg) is recommended. The LC-MS observations from the study showed no significant qualitative difference between control and micronutrient treatments with these treatments showing similar number of peaks. There was a significant quantitative difference between control and where magnesium peaks applied at adequate rates at (50 ml/l and 100 ml/l) and combination of (B + Zn + Fe + Cu + Mg) applied at (10 ml/l and 20 ml/l) / Agriculture, Animal Health and Human Ecology / M. Sc. (Agriculture)
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