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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.
1

Diversité structurelle et évolution contrastée des génomes cytoplasmiques des plantes à fleurs : une approche phylogénomique chez les Oleaceae / Structural diversity and contrasted evolution of cytoplasmic genomes in flowering plants : a phylogenomic approach in Oleaceae

Van de Paer, Céline 19 December 2017 (has links)
Chez les plantes, la dynamique structurelle et l'évolution concertée des génomes nucléaire et cytoplasmiques restent peu documentées. L'objectif de cette thèse était d'étudier la diversité structurelle et l'évolution des mitogénomes et des plastomes chez les Oleaceae à l'aide d'une approche de phylogénomique. Nous avons d'abord assemblé des mitogénomes à partir de données de séquençage de faible couverture, obtenues à partir de matériel frais et d'herbier. Une grande variation de structure du mitogénome a été observée chez l'olivier, et un gène chimérique potentiellement associé à un type de stérilité mâle a été identifié. Enfin, nous avons étudié l'évolution des plastomes et des gènes mitochondriaux chez les Oleaceae. Une accélération de l'évolution du plastome a été observée dans deux lignées indépendantes. Ce changement de trajectoire évolutive pourrait être la conséquence d'une transmission occasionnelle de plastes par le pollen, modifiant les pressions sélectives sur certains gènes. / In plants, the structural dynamics and concerted evolution of nuclear and cytoplasmic genomes are poorly understood. The objective of this thesis was to study the structural diversity and evolution of mitogenomes and plastomes in the family Oleaceae with a phylogenomic approach. First, we assembled mitogenomes from low-coverage sequencing data obtained from live and herbarium material. Considerable structural variation of mitogenomes was observed in the olive, and a chimeric gene potentially associated to a type of male sterility was detected. Finally, we studied the evolution of plastomes and mitochondrial genes in the Oleaceae. Accelerated evolution of plastomes was observed in two independent lineages. This change of evolutionary rate could be the consequence of an occasional transmission of plastids with pollen, modifying selective pressures on some genes.
2

Anti-oxidative, anti-inflammatory and hepato-protective effects of ligustrum robustum.

January 2000 (has links)
Lau Kit-Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 144-164). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.v / Declaration --- p.vi / Table of contents --- p.vii / List of Tables --- p.x / List of Figures --- p.xi / List of Abbreviations --- p.xv / Chapter Chapter One: --- General Introduction / Chapter 1.1 --- Tea and Ku-Ding-Cha --- p.1 / Chapter 1.2 --- Ligustrum robustum / Chapter 1.2.1 --- The plant --- p.4 / Chapter 1.2.2 --- Chemical constituents --- p.4 / Chapter 1.2.3 --- Pharmacological activities --- p.4 / Chapter 1.2.4 --- Toxicity --- p.5 / Chapter 1.3 --- Objectives and scope of the project --- p.7 / Chapter Chapter Two: --- Antioxidative effect / Chapter 2.1 --- Introduction / Chapter 2.1.1 --- Oxidants and antioxidants --- p.8 / Chapter 2.1.2 --- In vitro antioxidative tests / Chapter 2.1.2.1 --- PMS-NADH system --- p.19 / Chapter 2.1.2.2 --- Fe3+/ascorbate/H202 system --- p.19 / Chapter 2.1.2.3 --- Red-blood-cell hemolysis model --- p.20 / Chapter 2.2 --- Objectives --- p.22 / Chapter 2.3 --- Materials and Methods / Chapter 2.3.1 --- Materials / Chapter 2.3.1.1 --- Guizhou Ku-Ding-Cha --- p.23 / Chapter 2.3.1.2 --- Other tea leaves --- p.23 / Chapter 2.3.1.3 --- Animals --- p.23 / Chapter 2.3.1.4 --- Chemicals --- p.24 / Chapter 2.3.2 --- Methods / Chapter 2.3.2.1 --- Aqueous extraction of L. robustum and other tea leaves --- p.25 / Chapter 2.3.2.2 --- Ethanol extraction of L. robustum and fraction separations --- p.25 / Chapter 2.3.2.3 --- Activity-guided purification of L. robustum --- p.26 / Chapter 2.3.2.4 --- Assays for testing antioxidative effect / Chapter 2.3.2.4.1 --- PMS-NADH system --- p.28 / Chapter 2.3.2.4.2 --- Fe3+/ascorbate/H202 system --- p.28 / Chapter 2.3.2.4.3 --- Red-blood-cell hemolysis model --- p.29 / Chapter 2.3.2.5 --- Statistical analysis --- p.29 / Chapter 2.4 --- Results / Chapter 2.4.1 --- Ligustrum robustum and other tea leaves --- p.30 / Chapter 2.4.2 --- Ethanol extract of L. robustum --- p.48 / Chapter 2.4.3 --- Water-soluble and water-insoluble fractions --- p.52 / Chapter 2.4.4 --- "Fractions B1, B2 and B3" --- p.56 / Chapter 2.4.5 --- Sub-fractions B2-1 to B2-16 --- p.61 / Chapter 2.4.6 --- Pure compounds --- p.66 / Chapter 2.4.7 --- Changes in antioxidant effects --- p.72 / Chapter 2.5 --- Discussion / Chapter 2.5.1 --- Antioxidant potency of L. robustum --- p.76 / Chapter 2.5.2 --- Effects of extraction methods on antioxidant activities --- p.78 / Chapter 2.5.3 --- Active antioxidant components of L. robustum --- p.78 / Chapter 2.5.4 --- Structure-activity relationship of glycosides and flavonoid --- p.80 / Chapter 2.5.5 --- Antioxidant mechanism of L. robustum --- p.81 / Chapter 2.5.6 --- Prospects for further investigation --- p.82 / Chapter Chapter Three: --- Anti-inflammatory effect / Chapter 3.1 --- Introduction / Chapter 3.1.1 --- Mechanisms and mediators of inflammation --- p.83 / Chapter 3.1.2 --- In vivo anti-inflammatory assays / Chapter 3.1.2.1 --- Acetic acid-induced vascular permeability test --- p.94 / Chapter 3.1.2.2 --- Croton oil-induced ear edema test --- p.94 / Chapter 3.2 --- Objective --- p.96 / Chapter 3.3 --- Materials and Methods / Chapter 3.3.1 --- Materials / Chapter 3.3.1.1 --- Animals --- p.97 / Chapter 3.3.1.2 --- Chemicals --- p.97 / Chapter 3.3.2 --- Methods / Chapter 3.3.2.1 --- Assays for testing anti-inflammatory effect / Chapter 3.3.2.1.1 --- Acetic acid-induced vascular permeability test --- p.98 / Chapter 3.3.2.1.2 --- Croton oil-induced ear edema test --- p.98 / Chapter 3.3.2.2 --- Statistical analysis --- p.99 / Chapter 3.4 --- Results / Chapter 3.4.1 --- Acetic acid-induced vascular permeability test --- p.100 / Chapter 3.4.2 --- Croton oil-induced ear edema test --- p.100 / Chapter 3.5 --- Discussion --- p.103 / Chapter Chapter Four: --- Hepato-protective effect / Chapter 4.1 --- Introduction / Chapter 4.1.1 --- Liver structures and functions --- p.105 / Chapter 4.1.2 --- Carbon tetrachloride-induced liver injury --- p.112 / Chapter 4.1.2.1 --- Mechanisms --- p.112 / Chapter 4.1.2.2 --- Hepatic cytotoxicity --- p.112 / Chapter 4.1.2.3 --- Diagnostic methods / Chapter 4.1.2.3.1 --- Liver weight --- p.114 / Chapter 4.1.2.3.2 --- Lipid peroxidation --- p.114 / Chapter 4.1.2.3.3 --- Serum enzyme levels --- p.114 / Chapter 4.1.2.3.4 --- Histopathological observation --- p.115 / Chapter 4.2 --- Objectives --- p.116 / Chapter 4.3 --- Materials and Methods / Chapter 4.3.1 --- Materials / Chapter 4.3.1.1 --- Animals --- p.117 / Chapter 4.3.1.2 --- Chemicals --- p.117 / Chapter 4.3.2 --- Methods / Chapter 4.3.2.1 --- Carbon tetrachloride-induced acute liver injury --- p.118 / Chapter 4.3.2.2 --- Statistical analysis --- p.120 / Chapter 4.4 --- Results / Chapter 4.4.1 --- Preventive effect / Chapter 4.4.1.1 --- Liver weight --- p.121 / Chapter 4.4.1.2 --- Malondialdehyde content --- p.121 / Chapter 4.4.1.3 --- Serum aminotransferse levels --- p.121 / Chapter 4.4.1.4 --- Histopathological observations --- p.122 / Chapter 4.4.2 --- Curative effect / Chapter 4.4.2.1 --- Liver weight --- p.126 / Chapter 4.4.2.2 --- Malondialdehyde content --- p.126 / Chapter 4.4.2.3 --- Serum aminotransferse levels --- p.126 / Chapter 4.4.2.4 --- Histopathological observations --- p.126 / Chapter 4.5 --- Discussion --- p.130 / Chapter Chapter Five: --- Prospects for product development --- p.134 / Chapter Chapter Six: --- Conclusion --- p.136 / Appendices / Appendix A. Procedure for determining the activity of aspartate aminotransferase (AST) --- p.139 / Appendix B. Procedure for determining the activity of alanine aminotransferase (ALT) --- p.140 / Appendix C. Procedure for preparing a calibration curve for the measurement of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities --- p.141 / Appendix D. Procedure for tissue preparation for light microscopic study --- p.143 / References --- p.144
3

Antioxidative and vascular effects of kudingcha (Ligustrum purpurascens).

January 2000 (has links)
Wong Yuen Fan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 134-150). / Abstracts in English and Chinese. / ACKNOWLEDGMENTS --- p.i / ABSTRACT --- p.ii / LIST OF ABBREAIATIONS --- p.vii / TABLE OF CONTENTS --- p.ix / Chapter Chapter 1 --- General introduction / Chapter 1.1 --- History of Kudingcha --- p.1 / Chapter 1.2 --- Classification of Kudingcha --- p.1 / Chapter 1.3 --- Composition of Kudingcha --- p.3 / Chapter 1.4 --- Introduction to phenylethanoid glycosides --- p.4 / Chapter 1.4.1 --- Isolation and purification of phenylethanoid glycosides --- p.4 / Chapter 1.4.2 --- Taxonomy of phenylethanoid glycosides --- p.5 / Chapter 1.4.3 --- Structure of phenylethanoid glycosides --- p.5 / Chapter 1.4.4 --- Biosynthesis of phenylethanoid glycosides --- p.6 / Chapter 1.4.5 --- Pharmacological effects of phenylethanoid glycosides --- p.9 / Chapter 1.4.5.1 --- Anticarcinogenic activity --- p.10 / Chapter 1.4.5.2 --- Inhibitory activity of protein kinase C --- p.10 / Chapter 1.4.5.3 --- Immunosuppressive activity --- p.11 / Chapter 1.4.5.4 --- DNA repairing activity --- p.11 / Chapter 1.4.5.5 --- Antibacterial and antiviral activities --- p.11 / Chapter 1.4.5.6 --- Antiinflammatory and antinociceptive activities --- p.12 / Chapter 1.4.5.7 --- Hepatoprotective activity --- p.12 / Chapter 1.4.5.8 --- Inhibitory activity of xanthine oxidase --- p.13 / Chapter 1.4.5.9 --- Antioxidative and scavenging activities --- p.13 / Chapter Chapter 2 --- Isolation and purification of phenylethaonid glycosides in Kudingcha / Chapter 2.1 --- Introduction --- p.15 / Chapter 2.2 --- Objectives --- p.16 / Chapter 2.3 --- Materials and Methods --- p.17 / Chapter 2.3.1 --- Extraction and isolation --- p.17 / Chapter 2.3.2 --- High performance liquid chromatograph (HPLC)analysis --- p.19 / Chapter 2.3.2.1 --- "Acteoside, ligupurpuroside A and osmanthuside B" --- p.19 / Chapter 2.3.2.2 --- cis-Ligupurpuroside B and trans-ligupurpuroside B --- p.19 / Chapter 2.3.3 --- Isolation and purification of isoacteoside --- p.19 / Chapter 2.4 --- Results --- p.24 / Chapter 2.4.1 --- A cteoside --- p.24 / Chapter 2.4.2 --- Osmanthuside B --- p.24 / Chapter 2.4.3 --- Ligupurpuroside A --- p.24 / Chapter 2.4.4 --- trans-Ligupurpuroside B --- p.25 / Chapter 2.4.5 --- cis-Ligupurpuroside B --- p.25 / Chapter 2.4.6 --- Isoacteoside --- p.25 / Chapter 2.4.6.1 --- Thermal stability --- p.25 / Chapter 2.5 --- Discussions --- p.27 / Chapter 2.5.1 --- Acteoside --- p.27 / Chapter 2.5.2 --- Osmanthuside B --- p.27 / Chapter 2.5.3 --- Ligupurpuroside A --- p.28 / Chapter 2.5.4 --- trans-Ligupurpuroside B --- p.29 / Chapter 2.5.5 --- cis-Ligupurpuroside B --- p.29 / Chapter 2.5.6 --- Isoacteoside --- p.30 / Chapter Chapter 3 --- Inhibitory effect of phenylethanoid glycosides isolated from Kudingcha on Cu2+-mediated LDL oxidation in vitro / Chapter 3.1 --- Introduction --- p.36 / Chapter 3.2 --- Mechanisms of lipoprotein oxidation in vivo --- p.36 / Chapter 3.2.1 --- Oxidants underlying LDL oxidation --- p.36 / Chapter 3.2.2 --- Oxidative modification of LDL --- p.37 / Chapter 3.2.3 --- Role of oxidatively modified LDL in atherogenesis --- p.38 / Chapter 3.2.4 --- Antioxidants and atherosclerotic heart disease --- p.40 / Chapter 3.2.5 --- Measuring the thiobarbituric acid-reactive substances (TBARS) formation as an index to monitor LDL oxidation --- p.41 / Chapter 3.2.6 --- Effect of flavonoids on Cu2+-mediated human LDL oxidation --- p.41 / Chapter 3.3 --- Objectives --- p.43 / Chapter 3.4 --- Materials and methods --- p.44 / Chapter 3.4.1 --- LDL isolation --- p.44 / Chapter 3.4.2 --- LDL oxidation --- p.44 / Chapter 3.4.3 --- Thiobarbituric acid-reactive substances (TBARS) assay --- p.45 / Chapter 3.4.4 --- Interactions of phenylethanoid glycosides isolated from Kudingcha with Cu2+ in human LDL oxidation --- p.45 / Chapter 3.4.5 --- Statistics --- p.46 / Chapter 3.5 --- Results --- p.47 / Chapter 3.5.1 --- Protective effect of the major phenylethanoid glycosides isolated from Kudingcha on LDL oxidation --- p.47 / Chapter 3.5.2 --- Varying protective effect of individual major Kudingcha phenylethanoid glycosides --- p.47 / Chapter 3.5.3 --- Interactions of Kudingcha phenylethanoid glycosides with Cu2+in human LDL oxidation --- p.51 / Chapter 3.5 --- Discussions --- p.55 / Chapter Chapter 4 --- Inhibitory effects of Kudingcha phenylethanoid glycosides on a-tocopherol oxidation in vitro / Chapter 4.1 --- Introduction --- p.58 / Chapter 4.1.1 --- LDL oxidation and atherosclerosis --- p.58 / Chapter 4.1.2 --- Role of vitamin E in LDL lipid peroxidation --- p.59 / Chapter 4.1.3 --- Interaction of tocopherol interactions with other antioxidants and synergists --- p.61 / Chapter 4.2 --- Objectives --- p.62 / Chapter 4.3 --- Materials and Methods --- p.63 / Chapter 4.3.1 --- Depletion of a-tocopherol in LDL --- p.63 / Chapter 4.3.2 --- Regeneration of a-tocopherol in LDL --- p.63 / Chapter 4.3.3 --- HPLC analysis of a-tocopherol in LDL --- p.64 / Chapter 4.3.4 --- Statistics --- p.64 / Chapter 4.4 --- Results --- p.66 / Chapter 4.4.1 --- Protective effects of Kudingcha phenylethanoid glycosides on a-tocopherol depletion --- p.66 / Chapter 4.4.2 --- Regeneration of a-tocopherol by acteoside --- p.70 / Chapter 4.5 --- Discussions --- p.72 / Chapter Chapter 5 --- Relaxing effects of Kudingcha extract and purified acteoside in rat aortic rings / Chapter 5.1 --- Introduction --- p.75 / Chapter 5.1.1 --- Mechanisms of calcium mobilization --- p.76 / Chapter 5.1.1.1 --- Voltage-dependent calcium channel --- p.76 / Chapter 5.1.1.2 --- Thromboxane A2 Receptor-mediated calcium channel --- p.77 / Chapter 5.1.1.3 --- Protein kinase C in signal transudation --- p.77 / Chapter 5.1.2 --- Contractile proteins and regulation of contraction of vascular smooth muscle --- p.78 / Chapter 5.2 --- Objectives --- p.82 / Chapter 5.3 --- Materials and Methods --- p.83 / Chapter 5.3.1 --- Arterial ring preparation --- p.83 / Chapter 5.3.2 --- Vascular action of Kudingcha extract and acteoside --- p.85 / Chapter 5.3.2.1 --- Relaxant responses of Kudingcha extract and acteoside on U46619 -induced contraction --- p.85 / Chapter 5.3.2.2 --- Relaxant responses of Kudingcha extract and acteoside on high K+ and CaCl2-induced contraction --- p.85 / Chapter 5.3.2.3 --- Relaxant responses of Kudingcha extract and acteoside on protein kinase C- mediated contraction --- p.86 / Chapter 5.3.2.4 --- Effect of acteoside on acetylcholine-induced relaxation --- p.87 / Chapter 5.3.3 --- Statistics --- p.87 / Chapter 5.4 --- Results --- p.88 / Chapter 5.4.1 --- Effects of Kudingcha extract and acteoside on U46619-induced contraction --- p.88 / Chapter 5.4.2 --- Effects of Kudingcha extract and acteoside on high K+-induced contraction --- p.94 / Chapter 5.4.3 --- Effect of Kudingcha extract and acteoside on protein kinase C-mediated contraction --- p.98 / Chapter 5.4.4 --- Effect of acteoside on acetylcholine-induced relaxation --- p.100 / Chapter 5.5 --- Discussions --- p.103 / Chapter Chapter 6 --- Effect of Kudingcha on lipid contents of hamsters and New Zealand Rabbits / Chapter 6.1 --- Introduction --- p.106 / Chapter 6.1.1 --- Factors related to CHD --- p.106 / Chapter 6.1.2 --- Animal model --- p.107 / Chapter 6.2 --- Objectives --- p.108 / Chapter 6.3 --- Materials and Methods --- p.109 / Chapter 6.3.1 --- Rabbit --- p.109 / Chapter 6.3.1.1 --- Measurement of atheroma formation --- p.112 / Chapter 6.3.2 --- Hamster --- p.114 / Chapter 6.3.3 --- Serum lipid determinations --- p.116 / Chapter 6.3.4 --- Determination of hepatic cholesterol content --- p.116 / Chapter 6.3.5 --- Statistics --- p.117 / Chapter 6.4 --- Results --- p.119 / Chapter 6.4.1 --- Growth and Food intake --- p.119 / Chapter 6.4.2 --- "Effect of Kudingcha supplementation on Serum TG, TC and HDL-C" --- p.119 / Chapter 6.4.3 --- Effect of Kudingcha supplementation on hepatic cholesterol contents --- p.124 / Chapter 6.4.4 --- Effect of Kudingcha supplementation on atheroma formation --- p.124 / Chapter 6.5 --- Discussions --- p.129 / Chapter Chapter 7 --- Conclusions --- p.131 / References --- p.134
4

Phylogenetic hypothesis of the Oleeae tribe (Oleaceae) : diversification and molecular evolution patterns in plastid and nuclear ribosomal DNA / Reconstruction d'une hypothèse phylogénétique de la tribu d'Oleeaae (Oleaceae) à partir de l'ADN chloroplastique et nucléaire ribosomique : diversification et patrons d'évolution moléculaire

Zedane, Loubab 18 May 2016 (has links)
La tribu d'Oleeae (Oleaceae) est un modèle biologique très intéressant pour étudier la diversification et les patterns d'évolution moléculaire chez les plantes. Les reconstitutions de l'histoire évolutive et phylogénétique des relations entre ses espèces ont été au cœur de cette thèse. Ce travail a conduit à des progrès significatifs dans la résolution des relations phylogénétiques au sein de la tribu à différents niveaux taxonomiques. Nous avons démontré que l'utilisation d'une approche de "Genome Skimming" est très appropriée pour générer plastomes complets (ptDNA) et de l'ADN ribosomal nucléaire (nrDNA), même sur un échantillon d'herbier. Nous avons montré l'utilité du ptDNA pour reconstruire la première ossature phylogénétique robuste pour la tribu, et fourni de nouvelles connaissances sur l'histoire biogéographique et sur l'évolution de certains traits. Nous avons aussi montré que l'évolution de la composition en bases du nrDNA peut être influencée par des facteurs climatiques. / The Oleeae tribe (Oleaceae) is a very interesting biological model to investigate plant diversification and molecular evolution patterns. However, a comprehensive phylogeny is missing to accurately describe the evolutionary and biogeographic history of this tribe. Reconstructions the Oleeae evolutionary history and the phylogenetic relationships between its species were the core of this thesis. This work has led to significant progress in resolving the phylogenetic relationships within the tribe at different taxonomic levels. We demonstrated that the use of a shotgun approach is a highly suitable method to generate complete plastomes (ptDNA) and nuclear ribosomal DNA (nrDNA), even on herbarium sample. We showed the usefulness of ptDNA to reconstruct highly resolved phylogeny of Oleeae and provided new insights into the biogeographic history and the evolution of some traits. We also showed that the evolution of nrDNA base-composition seems to be influenced by environmental factors.

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