Thesis (M.S.)--University of Iowa, 2008. / Thesis supervisor: Bryant F. McAllister. Includes bibliographical references (leaves 68-75).

The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on March 29, 2010). Thesis advisor: Dr. Reginald B. Cocroft. Vita. Includes bibliographical references.

Title from title page of PDF (University of Missouri--St. Louis, viewed March 23, 2010). Includes bibliographical references.

Thesis (M.S.)--The University of North Carolina at Greensboro, 2009. / Directed by Malcolm Schug; submitted to the Dept. of Biology. Title from PDF t.p. (viewed May 11, 2010). Includes bibliographical references (p. 46-49).

Thesis (M.S.)--Montana State University, 2004. / Title from PDF title page (viewed Feb. 11, 2005). Includes bibliographical references (p. 54-60).

Thesis (doctoral)--Ludwig-Maximilians-Universität München, 2003. / Title from PDF t.p. (viewed on May 13, 2006). Vita. Includes bibliographical references (p. 128-137).

In a program aimed at the identification of compounds responsible for the immunosuppressive and antifertility activities of the perennial twining vine, Tripterygium wilfordii. 5 new and 13 known compounds were isolated from the TRP-4a tissue culture cell line developed from Tripterygium wilfordii. The structures of the new compounds were determined by a combination of spectral analysis, chemical correlation and single crystal X-ray diffraction analysis. 22β-Hydroxy-3-oxoolean-12-en-29-oic acid (137), 22α-hydroxy-3-oxoolean- 12- en-29-oic acid (138) and 3β, 22β-dihydroxyolean-12-en-29-oic acid (139) are new triterpenes possessing an oleanene-type skeleton and were chemically correlated with 3β, 22α-dihydroxyolean-12-en-29-oic acid (51), the structure of which was confirmed by single crystal X-ray diffraction analysis. Oleanolic acid (127), β-sitosterol (128) and polpunonic acid (55), were isolated previously from the TRP-4a cell line in earlier studies in this laboratory. α-Amyrin (145), β-amyrin (146), 3β, 29-dihydroxyolean-12-ene (151) and 3β, llα-dihydroxyolean-12-ene (152) are known triterpenes possessing an oleanene-type skeleton and are isolated for the first time from the TRP-4a cell line. Tingenone (148) and 22β-hydroxytingenone (150) are quinone methide triterpenes, also isolated for the first time from the TRP-4a cell line. Similarly, the novel diterpene, 12-methoxyabieta-8, 11, 13- trien-3α-ol (147) and the novel triterpene, methyl-22β-hydroxy-3, 21-dioxo-D:A-friedo-29-noroleanan-24-oate (149), a member of the friedelane family, are isolated for the first time. A biosynthetic pathway, based on the isolation of 149 and its structural similarity to polpunonic acid (55) and 22β-hydroxytingen6ne (150), is postulated for the quinone methides. The cytotoxic diterpenes, tripdiolide (1) and triptolide (2) and the hydroxy acid, 160, isolated as the methyl ester, 124, have been previously reported from this laboratory. Tripdiolide (1) and triptolide (2) have been shown to possess strong antifertility and immunosuppressive activities. In another aspect of our program, biotransformation studies of the synthetic precursors, 19 (4➙3)abeo-abieta-2, 8, 11, 13-tetraen-19-ol (171) and 19-hydroxy-18(4➙3)abeo-abieta-3, 8, 11, 13-tetraen-18-oic acid lactone (91), and the radioactive congeners, 182 and 209, were carried out using the TRP-4a cell line. It was hoped that the data obtained might shed some light on the "late stage" biosynthetic pathway of the diterpene triepoxides, tripdiolide (1) and triptolide (2). Synthesis of 171 was achieved in 5 steps from dehydroabietic acid (80). The radioactive congener, 182, was synthesised using ¹⁴C-paraformaldehyde with 0.4% incorporation of the radiolabel. Biotransformation of 171 using the TRP-4a cell line yielded 19(4➙3)abeo-abieta-2, 8, 11, 13-tetraen-19-al (185) and 19(4➙3)abeo-abieta-2, 8, 11, 13-tetraen-19-oic acid (186) for spectral identification. Biotransformation of 182 yielded the aldehyde, 183 (33.2%) and the acid, 184 (51.9%), the radioactive congeners of 185 and 186 respectively. Synthesis of 91 was achieved in 4 steps from dehydroabietic acid (80). The radioactive congener, 209, was synthesised using ¹⁴C-methyl iodide via ¹⁴C-dimethylsulphonium methylide, with 0.6% incorporation of the radiolabel. Biotransformation of 91 using TRP-4a tissue cultures yielded 19-hydroxy-7-oxo-18(4➙3)abeo-abieta-3, 8, 11, 13-tetraen-18-oic acid lactone (214), 2β, 19-dihydroxy-7-oxo-18(4➙3)abeo-abieta-3, 8, 11, 13-tetraen-18-oic acid lactone (215), 7β, 19-dihydroxy-18(4➙3)abeo-abieta-3, 8, 11, 13-tetraen-18-oic acid lactone (216) and 2β 19-dihydroxy-18(4➙3)abeo-abieta-3, 8, 11, 13-tetraen-18-oic acid lactone (96), for spectral identification. Biotransformation of 209 yielded the ketone, 210 (56.7%), the hydroxy ketone, 211 (5.9%), the benzylic alcohol, 212 (9.6%) and the C2 alcohol, 213 (6.8%), the radioactive congeners of 214,215,216 and 96 respectively. A biosynthetic pathway to the diterpene triepoxides is postulated based on the oxygenated biotransformation products. [formulas omitted] / Science, Faculty of / Chemistry, Department of / Graduate

Thesis (MSc)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: This study describes: 1. The isolation and the purification of tissue type plasminogen activator and urokinase plasminogen activator in bovine milk. 2. The biochemical characterisation of tissue type plasminogen activator in bovine milk. 3. An investigation of the influence of the addition of purified tissue type plasminogen activator to ultra high temperature milk, Gouda cheese and yoghurt. / AFRIKAANSE OPSOMMING: Hierdie studie beskryf: 1. Die isolering en suiwering van weefseltipe-plasminogeenaktiveerder en urokinase-plasminogeenaktiveerder in beesmelk. 2. Die biochemiese karakterisering van weefseltipe-plasmingeenaktiveerder in beesmelk. 3. `n Ondersoek na die invloed van die byvoeging van gesuiwerde weefseltipe-plasminogeenaktiveerder by ultra hoë temperatuur melk, Gouda kaas en joghurt.

Thesis (Ph. D.)--Ohio State University, 2009. / Title from first page of PDF file. Includes vita. Includes bibliographical references (p. 82-92).

What processes contribute to the evolution of reproductive isolation and the coexistence of interfertile species in the same habitat? This thesis investigates the relative roles of species interactions and intraspecific processes in contributing to reproductive isolation. I combine behavioural and genomic approaches to test hypotheses about what mechanisms maintain the general species boundary between two closely related field cricket species: Teleogryllus oceanicus and T. commodus. These species are a classic study system for sexual communication and readily hybridize in the laboratory, however little is known about species interactions in sympatric populations. I examine patterns of geographic variation in two key sexual traits: calling song and cuticular hydrocarbons (CHCs), and the geographic distribution of genetic variation across a broad sample of allopatric and sympatric populations. I test whether X chromosomes play a pronounced role in population divergence and reproductive isolation. Using close range mating trials and hybridization experiments I identify numerous pre-mating and post-mating barriers between the species. The results indicate that the species are currently reproductively isolated and the pattern of population differentiation does not strongly support contemporary species interactions contributing to phenotypic diversity. Numerous barriers exist between the species, in particular hybrid females are sterile in both cross directions, while hybrid males are relatively fertile. This provides a rare exception to Haldane's rule which is central to many genetic theories of speciation. Established theory predicts that X chromosomes should play a pronounced role in the evolution of both pre- and postzygotic barriers. Contrary to this, I found no evidence that X chromosomes contribute to hybrid female sterility. Moreover, X-linked loci exhibited an unexpected pattern of reduced population differentiation within species, but increased species divergence compared to autosomal loci, which may indicate selective sweeps or sex-biased processes. Taken together, the results suggest that the causes and consequences of X chromosome evolution, in particular among XO taxa, may contradict some of the established theories.