No description available.

No description available.

No description available.

The distribution of trypanosomes infecting wild ruminants of North America has only recently been investigated . Many isolates have been mensurally studied and were determined to be conspecific with Trypanosoma cervi. Widely divergent forms exist however, between host species and seasonally within a host . To determine the validity of all inclusions in the taxon and the extent of intraspecific variability , trypanosome isolates of moose, reindeer , antelope, muledeer, Roosevelt Elk and two discrete transplant populations of Rocky Mountain elk were characterized and differentiated using recombinant DNA techniques.

Thesis (Ph. D.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.

The objectives in this research were to assess whether Klebsiella planticola SDF20 could survive in soil and result in ecological effects to soil foodweb organisms and plant growth. Four experiments were conducted using soil microcosms. Klebsiella planticola SDF20 has been genetically engineered to produce ethanol from agricultural waste for use in alternative fuels. Theoretically, after ethanol is removed from fermentors, the remaining residue that includes SDF20 would be spread onto crop fields as organic amendments. The parent strain SDF15 and genetically engineered strain SDF20 were added to sandy and clay soils with varying organic matter content. Alterations to soil foodweb organisms and plant growth were assessed using direct methods. These alterations were considered to be ecological effects if changes in nutrient cycling processes and plant growth would result. Ethanol produced by SDF20 was detected in the headspace of microcosms that demonstrated that SDF20 can survive and express its novel function in high organic matter clay soil. Soil containing higher organic matter and higher clay content may have increased the survival of SDF20 due to less competition with indigenous microbiota for substrates and protection from bacterial predators in clay soil with smaller pore sizes, thereby allowing SDF20 to produce a detectable concentration of ethanol. Significant changes to soil foodweb organisms were not detected using this soil type. However, significant increases in soil nematodes and significant decreases in vescular-arbuscular mycorrhizal colonization of plant roots were detected after the addition of SDF20 to low organic matter clay, low organic matter sandy and high organic matter sandy soils. Significant changes in soil foodweb organisms associated with SDF20 occurred only when living plant roots were present. This indicated the importance of having biotic interactions in test systems to elucidate ecological effects. The effects associated with SDF20 varied with the chemical, physical and biological properties of soils and indicated the importance of assessing the release of genetically engineered microorganisms on a case by case basis. / Graduation date: 1996

No description available.

No description available.

A baculovirus (Spodoptera frugiperda) system was designed to express recombinant canine thyroid stimulating hormone (rcTSH). The efficacy of rcTSH was measured against pituitary derived bovine thyroid stimulating hormone (bTSH) through a series of in vitro and in vivo experiments. Initial purification of rcTSH was performed in order to characterize the hormone for further analyses. Ion exchange columns and tangential flow membranes were chosen based upon the traits of the rcTSH molecule. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) gels visualized by Coomassie blue, silver stain, and western blot demonstrated the effectiveness of the purification process. Primary cell, static tissue, and perifusion tissue cultures were employed to investigate in vitro thyroid cell/tissue response to rcTSH and bTSH. Canine thyroid cells were liberated from tissue samples, cultured, then exposed to TSH treatments in which media was subsequently harvested and measured for cyclic adenosine monophosphate (cAMP), a second messenger in the TSH downstream signaling cascade. The cAMP concentrations measured were sporadic and not consistent with expected concentrations for treatments or controls. For the static tissue culture, slices of bovine thyroid tissue were incubated and exposed to a series of media-only wash steps as well as treatment steps using varying concentrations of rcTSH. Unfortunately, the experiment was compromised resulting in the slow release of thyroxine (T4) for all samples due to tissue death. Perifusion experiments conducted on bovine thyroid tissue compared the release of T4 due to bTSH and rcTSH stimulation in a dynamic system. Unable to perform statistical analysis due to small sample sizes, graphical representation demonstrated stimulatory effects by bTSH and rcTSH when compared to control. Biological assays were used to compare the in vivo efficacy of rcTSH to bTSH which included 3 species (goldfish, rat, and canine). Results from mammalian experiments when subjected to analysis of variance (ANOVA) resulted in the rejection of the null hypothesis of equal means (P<0.05) between control, bTSH, and rcTSH treatments. Further analysis by Tukey's W procedure demonstrated the stimulatory actions of rcTSH and bTSH to be similar (P>0.05) to each other while greater (P<0.05) than control at the 4 and 6 hour post injection time.

Bibliography: leaves 215-236. / x, 249 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Scale-up of a biochemical process involving expression of an Insulin-like Growth Factor-I analogue (LongR3IGF-I) as inclusion bodies within the bacterium Escherichia coli has been investigated. The principal focus was directed to the operation of refolding wherein the biological potency of the protein is imparted. / Thesis (Ph.D.)--University of Adelaide, Dept. of Chemical Engineering, 1998?