Life Sciences Commons^™

Mechanisms Of Complement Resistance By Pathogenic Naegleria Fowleri Amoebae, Denise Marie Toney

Theses and Dissertations

The genus Naegleria is composed of a distinct group of free-living amoeboflagellates that include both pathogenic and nonpathogenic species. N. fowleri, the only pathogenic species of Naegleria to be isolated from humans, is the etiological agent of primary amoebic meningoencephalitis, a rare but rapidly fatal disease of the central nervous system in humans and in laboratory animals. The mechanisms of pathogenicity and the determinants of virulence of N. fowleri are unknown. Both pathogenic and nonpathogenic Naegleria activate the alternative complement pathway, however pathogenic N. fowleri are complement-resistant and nonpathogenic N. gruberi are complement-sensitive. The ability to resist complement-mediated lysis …

Characterization Of A Promoter Rearrangement And A Second Promoter In The Human C-Myb Proto-Oncogene, Sarah Margaret Jacobs

Theses and Dissertations

The human cellular proto-oncogene c-myb has been implicated as important in the regulation of hematopoietic cell growth and differentiation. Aberrant expression of this gene and chromosomal aberrations near the c-myb locus have been associated with a number of carcinogenic processes. An alternatively spliced CDNA clone of c-myb, pMbm-2, contains unique 5’ sequences which replace exon 1. The existence of this 5’ divergent CDNA clone led us into a study of the promoter activity of the c-myb gene.

Intron 1 of c-myb is highly conserved between human and mouse throughout the intron, while only those sequences directly adjacent to exons …

Identification Of Regulatory Mechanisms Of Genes Encoding Citrate Synthase In The Yeast Saccharomyces Cerevisiae, Christine Smith Kell

Theses and Dissertations

The major aim of this research was to investigate the molecular mechanisms of regulation of transcription of CIT1 and CIT2, the genes encoding citrate synthase in yeast. Specifically addressed are the questions of (1) localization of cis-acting sites required for expression or regulation, (2) the roles of HAP1 and HAP2,3,4 in expression of both genes, (3) identification of other trans-acting factors involved in expression of either gene, (4) localization of cis-acting sites involved in up regulation of CIT2 in response to disruption of CIT1 or rho° status (Liao et al., 1991; Liao and Butow, 1993).

I show here that mutations …

Sjögren-Larsson Syndrome: Genetic Studies And Biochemical Characterization Of Human Fatty Aldehyde Dehydrogenase, Todd L. Kelson

Theses and Dissertations

Sjögren-Larsson syndrome (SLS) is an autosomal recessive disorder due to deficiency of the fatty aldehyde dehydrogenase (FALDH) component of fatty alcohol:NAD⁺ oxidoreductase (FAO). We investigated the enzymatic defect in SLS in order to elucidate the role of FALDH in fatty aldehyde and fatty alcohol metabolism.

Genetic studies were performed to investigate carrier detection for SLS. Cultured skin fibroblasts from normal controls, SLS obligate heterozygotes, and SLS homozygotes were assayed for FAO and FALDH activities using 18-carbon substrates. In SLS homozygotes, mean FAO and FALDH activities were 8% of normal, and there was no overlap between the homozygote and heterozygote …

Immunomodulatory Effects Of Transforming Growth Factor-Β On T Lymphocytes, Thomas Harris Inge

Theses and Dissertations

Transforming growth factor-β1 (TGFβ) is a peptide cytokine implicated in control of growth, adhesion, and differentiation of cells in numerous tissues. TGFβ has potent inhibitory effects on many lymphocyte responses; we also found that TGFβ could inhibit in vitro generation of tumor-specific CTL. Suppression was largely reversed with exogenous IL-2. Proliferation of memory-stage CTL clones was also inhibited by TGFβ, while the upregulation of cytotoxicity was not inhibited by TGFβ. These studies suggested that TGFβ limited anti-tumor CTL responses via both an indirect effect on IL-2 production, and by a direct effect on proliferation of memory CTL.

In CTLL-2 cells, …

Distribution And Occurrence Of Eriogonum Visheri A. Nels. On The Medora And Mckenzie Districts, Little Missouri National Grasslands, In North Dakota, Staria S. Vanderpool

Theses and Dissertations

Eriogonum visheri A. Nels. (Polygonaceae) is a plant species whose distribution in North Dakota is incompletely known. The plant species is listed by North Dakota Heritage Program personnel as a G5/S2S3 [G5 = demonstrably secure globally, although it may be rare; S2 = imperiled in the state (6-20 occurrences) or vulnerable to extirpation; S3 = rare in the state (20+ occurrences)]. The species is Federally listed as C2 [current information indicates that listing as endangered or threatened may be warranted, but information about the species is presently inadequate to support immediate ruling] (Northern region, USDA Forest Service, 1991). The limited …

Report Of Developed Services In The El Pinalito Village Of The Chiquimula Municipality, Department Of Chiquimula, Fredy Samuel Coronado López

Theses and Dissertations

This paper reports on efforts to improve socioeconomic conditions and natural resource use in the El Pina lito community, department of Chiquimula, Guatemala. Students participating in supervised practical training at Centro Universitario de Oriente/Universidad de San Carlos de Guatemala (CUNORI) developed projects to address these issues. A general diagnostic instrument was created for this community to assist in the development of specific work projects. Students prepared community first-aid kits, agricultural activities with school children, and instructional sessions with farmers on how to prepare a family garden and efficiently manage domestic animals. Other activities included ornamental tree preparation for female participants …