It is the intent of the author to investigate the evolution of Astragalus in Utah. Variation in the stomatal complex of the leaf epidermis was the primary mechanism used to study this problem the results of which were related to a posslble phylogenetic scheme for the genus. Stomatal complexes of 72 of the 128 species and varieties of Astragalus known to occur in Utah were studied using plastic impressions of the epidermal leaf tissue. The stomatal complex of each species and variety treated in this study was illustrated and then phylogenetically analyzed by 4 criteria: (1) size relationships between cells surrounding the stoma and cells in the ground epidermis; (2) variation (in percent) of the number of cells surrounding the stoma at the interspecific and intervarietal levels; ( 3) the mean length (in microns) of the guard cells; and ( 4) the number of stoma per square millimeter.

The purpose of this study is to investigate the level and distribution of genetic variation in Astragalus jaegerianus by using molecular markers. The objectives of the study are: to estimate levels of genetic variation within and among populations of Astragalus jaegerianus; to test the hypothesis that levels and patterns of genetic variation in species of restricted ranges and few individuals is low and partitioned at the population level; and to discern whether, or how well, genetic partitioning of Lane Mountain milk vetch correlates with its geographic partitioning in the field.

Yip Pui Ying. / Thesis submitted in: November 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 147-184). / Abstracts in English and Chinese. / Abstract --- p.i / 摘要 --- p.iii / Acknowledgment --- p.v / Abbreviations --- p.vii / Table of contents --- p.viii / List of Figures --- p.xii / List of Tables --- p.xvii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1. --- The importance of characterization of Chinese medicinal materials and the development of Chinese medicine in Hong Kong --- p.1 / Chapter 1.2. --- Methods for characterization of Chinese medicinal materials --- p.5 / Chapter 1.3. --- Molecular characterization of Chinese medicinal materials --- p.8 / Chapter 1.3.1. --- DNA sequencing --- p.9 / Chapter 1.3.2. --- DNA fingerprinting --- p.14 / Chapter 1.3.3. --- Nucleic acid hybridization --- p.19 / Chapter 1.4. --- Objectives --- p.20 / Chapter Chapter 2 --- Characterization of Plant and Fungal Materials by rDNA ITS Sequence Analysis --- p.22 / Chapter 2.1. --- Introduction --- p.22 / Chapter 2.2. --- Materials and Methods --- p.22 / Chapter 2.2.1. --- Chinese medicinal materials used in this study --- p.22 / Chapter 2.2.1.1. --- Plants and fungi for interspecific ITS study --- p.22 / Chapter 2.2.1.2. --- Plant for intraspecific ITS study and locality study --- p.33 / Chapter 2.2.2. --- Extraction of total DNA --- p.35 / Chapter 2.2.3. --- PCR amplification of ITS1 and ITS2 regions of rRNA gene --- p.35 / Chapter 2.2.4. --- Purification of PCR products --- p.38 / Chapter 2.2.5. --- Cloning using pCR-Script´ёØ Amp SK(+) Cloning Kit --- p.38 / Chapter 2.2.5.1. --- Polishing --- p.38 / Chapter 2.2.5.2. --- Ligation of inserts into pCR-Script´ёØ Amp SK(+) cloning vector --- p.38 / Chapter 2.2.5.3. --- Transformation --- p.40 / Chapter 2.2.5.4. --- PCR screening of white colonies --- p.40 / Chapter 2.2.5.5. --- Purification of PCR screening products --- p.41 / Chapter 2.2.6. --- Sequencing of ITS regions --- p.41 / Chapter 2.2.6.1. --- Cycle sequencing reaction --- p.41 / Chapter 2.2.6.2. --- Purification of sequencing extension products --- p.41 / Chapter 2.2.6.3. --- Electrophoresis by genetic analyzer --- p.42 / Chapter 2.2.7. --- Sequence analysis and alignment --- p.42 / Chapter 2.3. --- Results --- p.42 / Chapter 2.3.1. --- Extraction of total DNA --- p.42 / Chapter 2.3.2. --- PCR amplification of ITS1 and ITS2 regions of rRNA gene --- p.44 / Chapter 2.3.2.1. --- Interspecific ITS study --- p.44 / Chapter 2.3.2.2. --- Intraspecific ITS study --- p.46 / Chapter 2.3.3. --- Sequence analysis and alignment --- p.47 / Chapter 2.3.3.1. --- Interspecific ITS study --- p.47 / Chapter 2.3.3.2. --- Intraspecific ITS study --- p.56 / Chapter 2.4. --- Discussions --- p.60 / Chapter 2.4.1. --- rDNA regions used for studying Chinese medicinal materials --- p.60 / Chapter 2.4.2. --- The results agreed with previously published works --- p.60 / Chapter 2.4.3. --- Explanation of interspecific results within the Ganoderma genus --- p.60 / Chapter 2.4.4. --- Implications from interspecific comparisons --- p.60 / Chapter 2.4.5. --- Implications from intraspecific comparisons --- p.61 / Chapter Chapter 3 --- .Characterization of Astragalus membranaceus by DNA Fingerprinting / Chapter 3.1 --- Introduction --- p.62 / Chapter 3.2 --- Materials and Methods --- p.62 / Chapter 3.2.1 --- Extraction of total DNA --- p.62 / Chapter 3.2.2 --- Generation and detection of DNA fingerprints by AP-PCR --- p.63 / Chapter 3.2.3 --- Analysis of DNA fingerprints --- p.63 / Chapter 3.3 --- Results --- p.63 / Chapter 3.3.1 --- Generation of DNA fingerprints by AP-PCR --- p.63 / Chapter 3.3.2 --- Fingerprint analysis --- p.69 / Chapter 3.4 --- Discussion --- p.85 / Chapter 3.4.1 --- RP-PCR has been used on Chinese medicinal materials --- p.85 / Chapter 3.4.2 --- AP-PCR used instead of RAPD --- p.85 / Chapter 3.4.3 --- Reproducibility and amount of bands --- p.86 / Chapter 3.4.4 --- Alternatives of electrophoresis process --- p.88 / Chapter 3.4.5 --- Explanation of results --- p.88 / Chapter 3.4.6 --- Distinguishing Neimengu and Shanxi samples --- p.89 / Chapter 3.4.7 --- Further studies --- p.90 / Chapter Chapter 4 --- Characterization of Plant and Fungal Materials by DNA-DNA Hybridization on Microarrays --- p.91 / Chapter 4.1 --- Introduction --- p.91 / Chapter 4.2 --- Materials and Methods --- p.92 / Chapter 4.2.1 --- Samples for microarray study --- p.92 / Chapter 4.2.2 --- Extraction of total DNA --- p.95 / Chapter 4.2.3 --- Amplification and sequencing of ITS 1 region of rRNA gene --- p.95 / Chapter 4.2.4 --- Preparation of labeled probe --- p.95 / Chapter 4.2.5 --- Amplification of ITS1 fragments --- p.97 / Chapter 4.2.6 --- Preparation of slides --- p.103 / Chapter 4.2.7 --- Hybridization and washing --- p.104 / Chapter 4.2.8 --- Scanning and data analysis --- p.105 / Chapter 4.3 --- Results --- p.105 / Chapter 4.3.1 --- DNA extraction --- p.105 / Chapter 4.3.2 --- Amplification and sequencing of ITS1 region of rRNA gene --- p.107 / Chapter 4.3.3 --- Preparation of labeled probe and amplification of ITS1 fragments… --- p.112 / Chapter 4.3.4 --- Preparation of slides --- p.112 / Chapter 4.3.5 --- Scanning and data analysis --- p.116 / Chapter 4.4 --- Discussion --- p.134 / Chapter 4.4.1 --- Implications --- p.134 / Chapter 4.4.2 --- Applying the findings --- p.134 / Chapter 4.4.3 --- Ways to maximize specificity --- p.137 / Chapter 4.4.4 --- Optimisation --- p.138 / Chapter 4.4.5 --- Microarray may be more advantageous over sequencing --- p.138 / Chapter Chapter Five --- General Discussion and Summary --- p.140 / Chapter 5.1. --- Objectives of this study --- p.140 / Chapter 5.2. --- rDNA ITS sequencing --- p.140 / Chapter 5.2.1. --- Description of the approach and summary of the results --- p.140 / Chapter 5.2.2. --- Implications from the results --- p.140 / Chapter 5.2.3. --- Advantages and limitations of DNA sequencing --- p.141 / Chapter 5.3. --- AP-PCR fingerprinting --- p.141 / Chapter 5.3.1. --- Description of the approach and summary of the results --- p.141 / Chapter 5.3.2. --- Advantages and limitations of DNA fingerprinting --- p.142 / Chapter 5.4. --- DNA-DNA hybridization on microarrays --- p.143 / Chapter 5.4.1. --- Description of the approach and summary of the results --- p.143 / Chapter 5.4.2. --- Implications from the results --- p.143 / Chapter 5.4.3. --- Advantages and limitations of DNA hybridization on microarrays. --- p.144 / Chapter 5.5. --- Overall summary --- p.144 / Chapter 5.6. --- Future studies --- p.146 / References --- p.147 / Appendix --- p.185

Pancreatic cancer is known to be one of the most life-threatening cancers characterized by aggressive local invasion and distant metastasis. The high basal level of autophagy in pancreatic cancer may be responsible for the low chemotherapeutic drug response rate and poor disease prognosis. However, the clinical application of autophagy inhibitors was unsatisfactory due to their toxicity and minimal single-agent anticancer efficacy. Hence, oncologists begin to consider the tumor microenvironment when exploring new drug targets. In the present study, the anti-tumorigenic mechanisms of two major phytochemicals derived from Chinese medicinal herbs had been investigated against pancreatic cancer development. Calycosin is a bioactive isoflavonoid of the medicinal plant Astragalus membranaceus. Our results have shown that calycosin inhibited the growth of various pancreatic cancer cells both in vitro and in vivo by inducing cell cycle arrest and apoptosis. Alternatively, calycosin also facilitated MIA PaCa-2 pancreatic cancer cell migration in vitro and increased the expression of epithelial-mesenchymal transition (EMT) biomarkers in vivo. Further mechanistic study suggests that induction of the Raf/MEK/ERK pathway and facilitated polarization of M2 tumor-associated macrophage in the tumor microenvironment both contribute to the pro-metastatic potential of calycosin in pancreatic cancer. These events appear to be associated with calycosin-evoked activation of TGF-β signaling, which may explain the paradoxical drug actions due to the dual roles of TGF-β as both tumor suppressor and tumor promoter in pancreatic cancer development under different conditions. Isoliquiritigenin (ISL) is a chalcone obtained from the medicinal plant Glycyrrhiza glabra, which can be a precursor for chemical conversion to form calycosin. Results have shown that ISL decreased the growth and EMT of pancreatic cancer cells in vitro, probably due to modulation of autophagy. ISL-induced inhibition of autophagy subsequently promoted reactive oxygen species (ROS) production, leading to induction of apoptosis in pancreatic cancer cells. Such phenomenon also contributed to the synergistic growth-inhibitory effect in combined treatment with the orthodox chemotherapeutic drug 5-fluorouracil. In addition, ISL-induced tumor growth inhibition in vivo was further demonstrated in a tumor xenograft mice model of pancreatic cancer. ISL promoted apoptosis and inhibited autophagy in the tumor tissues. Study on immune cells indicates that ISL could reduce the number of myeloid-derived suppressor cells (MDSCs) both in tumor tissue and in peripheral blood, while CD4+ and CD8+ T cells were increased correspondingly. In vitro test has revealed that ISL inhibited the polarization of M2 macrophage along with its inhibition of autophagy in M2 macrophage. These immunomodulating effects of ISL had reversed the pro-invasive role of M2 macrophage in pancreatic cancer.In conclusion, calycosin acts as a "double-edged sword" on the growth and metastasis of pancreatic cancer, which may be related to the dual roles of TGF-β and its influence on the tumor microenvironment. Alternatively, ISL consistently inhibited the growth and metastatic drive of pancreatic cancer through regulation of autophagy and reprogramming of the immune system. The differential modes of action of these compounds have provided new insights in the development of effective pancreatic cancer treatment adjuvants.

Sheep and goat formed the foundation of pastoral activity across the Central Asian steppe through the Bronze Age. Theories of pastoral activity have assumed that flocks were uniform in association with ethnic groups that crossed the steppe with new ceramic forms and technologies. This study investigated differences between flocks of sheep and goat across the eastern Kazakh steppe in the Late and Final Bronze Age to elucidate the potential for animal exchange and mobility. Geometric morphometric techniques were applied to archaeological astragali from Ovis aries and Capra hircus. The methods for measurement and analysis were carefully developed to control only for inherited characteristics that relate to environmentally driven adaptations in the movement of the hind limb. Efficiency of movement in this limb is tied to survival and reproductive success of animals. Specimens were selected from three archaeological sites located in different ecozones across the steppe to maximize ecological variability. Geometric morphometric results revealed that flocks of sheep exhibited unique astragalus morphology, indicating that crossbreeding and exchange did not occur between sites. These sites were also subjected to full zooarchaeological analyses to investigate variability of economic subsistence patterns. The total number of species as well as investigations into survival and skeletal body part representation revealed that each site had unique subsistence patterns that were related to local ecological resource availability, despite material culture links. This variability in subsistence patterns and flock uniformity indicate that animal trade was not a feature of steppe networks. Local lifeways were specific to small patches of the steppe, despite overarching shared material cultures.

Patterns in the distribution of homoplasy are investigated from theoretical and empirical perspectives. The history of the term "homoplasy" as used by morphologists, evolutionary systematists, cladists, and others is reviewed, especially in relation to its complement, "homology." Homoplasy is defined relative to homology, which is viewed as any similarity shared through an unbroken line of common ancestry. An investigation of levels of homoplasy based on a statistical analysis of 60 published phylogenies reveals a strong dependence of homoplasy on the number of taxa included. This relation is independent of number of characters, type of data, taxonomic rank, or organism, and suggests that large taxa should be the focus of empirical studies of homoplasy. Hence, a phylogenetic analysis of the large genus Astragalus was undertaken using 113 representative species (and varieties) found in North America. Fifty-seven binary and multistate characters were scored and the resulting matrix was subjected to numerical cladistic analysis. Two large sets of equally parsimonious trees were found at 595 and 596 steps. The sets were analyzed using consensus methods, robust clades were discussed in detail, and the phylogenies were compared to previous classifications. Character evolution of a large set of taxonomically important and morphologically varied traits was investigated. Statistical tests were developed to detect patterns of topological clustering of homoplastic character changes in cladograms. The tests use Monte-Carlo computer simulations of four null models of character evolution in an attempt to reject the hypothesis of random homoplastic distributions. For the Astragalus data set only two of 17 characters were significantly clustered, and this is close to random expectation. Another data set from the literature was also tested, and in it no characters were clustered at the 5 percent level. The explanation for these negative findings regarding homoplastic "tendencies" is explored with respect to "scope", "scale", and character "resolution," factors believed to play an important role in the analysis of character evolution.

Lai, Kwok Kin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 229-251). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Tam, Chor Wing Jacqueline. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 322-359). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

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Astragalus lentiginosus, which consists of 36 varieties, is one of the principal locoweeds of western North America. The objectives of this study included identification of some of the major factors affecting germination of the seed and survival of the newly established seedlings for several of these varieties. The seeds of the varieties studied exhibited two mechanisms for dormancy. One is a seed coat that is impermeable to water, and the other is a water-leachable inhibitor. The presence or absence of low-intensity incandescent light (in 14-hour day lengths) had no effect on germination. Of three temperature regimes studied, the regime 7/13 C proved optimal for both total and rapid rate of germination. However, though germinating at lower rates, weeds at -1/4 C and 21/27 C both ultimately reached high percentages of germination. Germination decreased linearly with increasing salinity to almost zero in NaCl solutions of -8.52 bars water potential. Variety araenosus, collected in a salt desert shrub vegetation type showed the highest germination at low temperatures and the greatest salinity tolerance. Seedling survival work was done with both pre-established and established seedlings at the cotyledon to five leaflet stages of development. Seedlings were considered pre-established from the time of germination until the cotyledons were completely unfolded. Afterwards, the seedlings were considered established. Germination and survival of pre-established seedlings were inhibited by day temperatures of 21 C under laboratory conditions. Maximum emergence and survival occurred at the low temperature regime of 4/13 C. However, seedlings of the three to five leaflet stages grew best at day temperatures of 30 C; growth was substantially lower at lower temperatures. Seedlings of var. araenosus displayed the most rapid rate of root growth at 7/12 C while roots of var. vitreus grew at a rate nearly 50 percent lower.