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Giardia Lamblia: Genomic And Molecular Analyses Of Flippase, Diana Leticia Villazana-Kretzer

Open Access Theses & Dissertations

Giardia lamblia, is an intestinal protozoan parasite responsible as a major cause of water-borne intestinal infection in humans (giardiasis). It has been proposed earlier that Giardia has limited lipid synThesis ability and therefore relies on preformed lipid molecules from outside sources. It has also been proposed that lipids are taken up through passive and active transport, and giardial flippasse play a significant role in this process. This study describes the identification and characterization of a putative homologue of flippase gene from Giardia. Flippase is an enzyme that functions as a trans-bilayer transport system facilitating the flip flop diffusion of phospholipids …

Evolutionary And Structural Analyses Of Alpha-Papillomavirus Capsid Proteins Yields Novel Insights Into L2 Structure And Interaction With L1, John Lowe, Debasis Panda, Suzanne Rose, Ty Jensen, Willie Hughes, For Yue Tso, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

Background: PVs (PV) are small, non-enveloped, double-stranded DNA viruses that have been identified as the primary etiological agent for cervical cancer and their potential for malignant transformation in mucosal tissue has a large impact on public health. The PV family Papillomaviridae is organized into multiple genus based on sequential parsimony, host range, tissue tropism, and histology. We focused this analysis on the late gene products, major (L1) and minor (L2) capsid proteins from the family Papillomaviridae genus Alpha-papillomavirus. Alpha-PVs preferentially infect oral and anogenital mucosa of humans and primates with varied risk of oncogenic transformation. Development of evolutionary associations between …

Retrocyclin Rc-101 Overcomes Cationic Mutations On The Heptad Repeat 2 Of Hiv-1 Gp41, Christopher Fuhrman

Electronic Theses and Dissertations

Retrocyclin RC-101, a θ-defensin with lectin-like properties, potently inhibits infection by many HIV-1 subtypes by binding to the heptad repeat (HR)-2 region of gp41 and preventing six-helix bundle formation. In the present study, we used in silico computational exploration to identify residues of HR2 that interacted with RC-101 and then analyzed the HIV-1 Sequence Database at LANL for residue variations in the HR1 and HR2 segments that could plausibly impart in vivo resistance. Docking RC-101 to gp41 peptides in silico confirmed its strong preference for HR2 over HR1, and implicated residues crucial for its ability to bind HR2. We mutagenized …

Life Cycle Of A Torrenticolous Hawaiian Chironomid (Telmatogeton Torrenticola): Stream Flow And Microhabitat Effects, M. Eric Benbow, Albert J. Burky, Carl M. Way

Biology Faculty Publications

In this study we documented the instar densities and life cycle of Telmatogeton torrenticola Terry (Chironomidae : Telmatogetoninae) from Kinihapai Stream, Maui, Hawaii. Greatest larval densities of this midge are found on substrates of high velocity, shallow flows of cascades, and splash zones of waterfalls, with lower densities in riffles. In the summer of 1994 we compared the effects of two microhabitats (termed optimal and suboptimal) on inter-instar density and relative abundance. In a second year (1995), we evaluated the effect of long-term reduced stream flow on these variables only in optimal microhabitats. A significant reduction in stream flow from …

Human Papillomavirus Virus-Like Particles Are Efficient Oral Immunogens When Coadministered With Escherichia Coli Heat-Labile Enterotoxin Mutant R192g Or Cpg Dna, S. Gerber, C. Lane, Deborah M. Brown, E. Lord, M. Dilorenzo, J. D. Clements, E. Rybicki, A.-L. Williamson, R. C. Rose

Nebraska Center for Virology: Faculty Publications

Certain human papillomaviruses (HPVs) cause most cervical cancer, which remains a significant source of morbidity and mortality among women worldwide. HPV recombinant virus-like particles (VLPs) are promising vaccine candidates for controlling anogenital HPV disease and are now being evaluated as a parenteral vaccine modality in human subjects. Vaccines formulated for injection generally are more costly, more difficult to administer, and less acceptable to recipients than are mucosally administered vaccines. Since oral delivery represents an attractive alternative to parenteral injection for large-scale human vaccination, the oral immunogenicity of HPV type 11 (HPV-11) VLPs in mice was previously investigated; it was found …

Biological Characterization Of Rev Variation In Equine Infectious Anemia Virus, Michael Belshan, Matthew E. Harris, Anne E. Shoemaker, Thomas J. Hope, Susan Carpenter

Nebraska Center for Virology: Faculty Publications

Sequence analysis identified significant variation in the second exon of equine infectious anemia virus (EIAV) rev. Functional analysis indicated that limited amino acid variation in Rev significantly altered the export activity of the protein but did not affect Rev-dependent alternative splicing. EIAV Rev can mediate export through two independent cis -acting Rev-responsive elements (RREs), and differences among Rev variants were more pronounced when both RREs were present. Variation in Rev may be an important mechanism for regulation of virus replication in vivo and may contribute to changes in clinical disease.

Longitudinal Studies Of Viral Sequence, Viral Phenotype, And Immunologic Parameters Of Human Immunodeficiency Virus Type 1 Infection In Perinatally Infected Twins With Discordant Disease Courses, Cecelia Hutto, Yi Zhou, Jun He, Rebeca Geffin, Martin Hill, Walter Scott, Charles Wood

Nebraska Center for Virology: Faculty Publications

Perinatal human immunodeficiency virus type 1 (HIV-1) infections cause a broad spectrum of clinical disease and are variable in both the age of the patient at onset of serious disease and the progression of the clinical course. Heterozygotic perinatally infected twins with a marked difference in their clinical courses were monitored during the first 2 years of life. Twin B, the second-born twin, developed AIDS by 6 months of age and died at 22 months of age, while twin A remained minimally symptomatic through the first 2 years. Sequential blood specimens were obtained from the twins in order to characterize …

The Lipooligosaccharides Of Haemophilus Ducreyi Are Highly Sialylated, William Melaugh, A A. Campagnari, B W. Gibson

Chemistry Faculty Publications

The major lipooligosaccharides of the sexually transmitted pathogen Haemophilus ducreyi 35000 have been previously found to terminate in N-acetyllactosamine and sialyl-N-acetyllactosamine, Neu5Ac alpha 2-->3Gal beta 1-->4GlcNAc (W. Melaugh, N. J. Phillips, A. A. Campagnari, M. V. Tullius, and B. W. Gibson, Biochemistry 33: 13070-13078, 1994). In this study, mass spectrometry and composition analyses have shown that the lipooligosaccharides from three other H. ducreyi strains also contain N-acetyllactosamine and are highly sialylated (approximately 30 to 50%), although one African strain was found to contain neither of these structural features.

Phylogenetic Diversity Of The Bacterial Community From A Microbial Mat At An Active, Hydrothermal Vent System, Loihi Seamount, Hawaii, Craig L. Moyer, Fred C. Dobbs, David M. Karl

OES Faculty Publications

The phylogenetic diversity of small-subunit rRNA genes associated,vith the domain Bacteria was examined (by using previously defined operational taxonomic units [C. L. Moyer, F. C. Dobbs, and D. M. Karl, Appl. Environ. Microbiol. 60:871-879, 1994]; those for Pele's Vents Bacteria are hereafter abbreviated PVB OTUs) with samples from a microbial mat at an active, deep-sea hydrothermal vent system. A cluster of phylogenetically related PVB OTUs (OTUs 2, 3, 6, and 8) was closely affiliated with Thiovulum sp. contained within the epsilon subclass of the class Proteobacteria and accounted for 60.5% of the small-subunit rRNA bacterial clone library from Pele's Vents. …

An Improved Method For Chemical Devitellinization Of X-Gal Stained Drosophila Embryos, Amit Singh, Madhuri Kango-Singh, P. Sinha

Biology Faculty Publications

In Drosophila developmental biological studies, X-gal staining is commonly employed to study the spatio-temporal expression of the lacZ reporter gene in the transformed flies or their embryos. Study of the lacZ pattern in embryos often suffers from the lack of an efficient and high yieldirrg technique for devitellinization of X-gal stained embryos. Devitellinization techniques employed during antibody staining, in situ hybridization or embryonic cuticular preparations generally do not give satisfactory results when used for similar purpose in X-gal stained embryos. This results in the flaky appearance of the blue stain. We present here an improved chemical devitellinization technique which gives …

Use Of Pyocin To Select A Haemophilus Ducreyi Variant Defective In Lipooligosaccharide Biosynthesis, A A. Campagnari, R Karalus, M A. Apicella, William Melaugh, A J. Lesse, B W. Gibson

Chemistry Faculty Publications

Haemophilus ducreyi, a cause of genital ulcer disease in developing countries, appears to facilitate the heterosexual transmission of the human immunodeficiency virus in Africa. Despite an increase in studies of this gram-negative human pathogen, little is known about the pathogenesis of chancroid. Our studies have shown that the lipooligosaccharides (LOS) of H. ducreyi may play an important role in ulcer formation. Monoclonal antibody and mass spectrometric analyses identified a terminal trisaccharide present on H. ducreyi LOS that is immunochemically similar to human paragloboside. This epitope is present on the LOS of Neisseria gonorrhoeae, and it may be the site of …

Antibiotic Effects On Coliform Enumeration, Keith Leonard Wozniak

Masters Theses

The inhibitory effects of Bacillus polymyxa on Escherichia coli were studied. Significant coliform inhibition was observed. The inhibitory agent (presumably polymyxin) was active against coliforms after a one hour holding time. Different suspending menstrua were analyzed for their effects on coliform inhibition. It was observed that Peptone water provided the highest recovery of coliforms while phosphate buffer provided less protection. Two methods of enumeration were also studied as to their ability to quantify coliforms inhibited by B. polymyxa. Comparable inhibition was shown using both methods. No significant differences exist between the Standard Plate Count and Membrane Filter techniques. Overall, …

A Limnological Study Of 43 Selected Maine Lakes, Derrill J. Cowing, Matthew Scott

Maine Collection

A Limnological Study of 43 Selected Maine Lakes

by Derrill J. Cowing and Matthew Scott

U.S. Geological Survey : Water-Resources Investigations 80-69

Prepared in cooperation with the Maine Department of Environmental Protection

U.S. Geological Survey, 26 Ganneston Drive, August, Maine 04330

Effect Of Cold Shock On The Metabolism Of Trichomonas Gallinae, James J. Daly

Journal of the Arkansas Academy of Science

The influence of cold (4°C) used to prepare cells for metabolic investigations was examined with Trichomonas gallinae in this study. Cells washed with cold diluent in a refrigerated centrifuge were found to be less stimulated in their gas production at 37°C when exposed to glucose or maltose than cells washed at room temperature conditions. Such cold-prepared cells had higher initial glycogen contents after washing, faster endogenous glycogen degradation rates when incubated at 37 °C, but lower glycogen synthesis in the presence of glucose or maltose when compared to cells not prepared in the cold. However, uptake of glucose and maltose …

Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation

Publications (WR)

Progressive increases in concentration of dissolved solids in the Colorado River water from Lake Powell to Imperial Dam seem to alter plankton dynamics and biological productivity of the river. Also, changes in biological productivity and micronutrients concentrations occur within the same reservoir. Development of a digital simulation model to predict micronutrients concentrations and biological productivity is necessary for diagnosing changes in plankton population and effluent-carrying capacity of the system. The objectives of the study are: (1) to determine trace metal balance at different locations in Lake Mead, (2) to measure biological productivity and conduct plankton population counts at each sampling …

Facility For The Biological Treatment Of A Complex Chlorophenolic Waste - A Preliminary Report, William F. Evans

Journal of the Arkansas Academy of Science

The City of Jacksonville, Arkansas, is attempting to determine if aeration of a combined domestic sewage — chlorophenolic herbicide waste prior to release into conventional waste stabilization lagoons will be useful in the microbiological oxidation of chlorophenols and chlorophenoxy acids.

The Effect Of Gamma Irradiation On Growth Of Seven Strains Of Trypanosoma Avium, Roy Wesley Leid Jr.

All Master's Theses

The prime motivating factor in the present study was the desire to show significant differences in radio-sensitivities within six strains of Trypanosoma avium. A seventh strain was later added for the last two irradiation treatments. Gross morphology and differences in growth curves associated with varying temperatures suggested that the strains being cultured were not the same. With these differences in mind, the strains were subjected to different dosage levels of gamma irradiation.

Biological Studies Of Selected Reaches And Tributaries Of The Colorado River, Nelson Thomas, Federal Water Pollution Control Administration

Publications (WR)

This report fulfills the request of the Colorado River Basin Project, Denver, Colorado, to determine the effects of municipal and industrial wastes on the aquatic life in selected waters of the Colorado River Basin. These studies were conducted with the assistance of personnel from the Colorado River Basin Project.

Complementarity Between The Deoxyribonucleic Acid Of Bacteriophage P4/2 And That Of Its Naturally Lysogenic Host Salmonella Potsdam Strain 4, Londa Liseli Schmidt

Loma Linda University Electronic Theses, Dissertations & Projects

Complementarity studies were conducted between bacteriophage P4/2 DNA and the DNAs of its naturally lysogenic host Salmonella potsdam strain 4 (SP4) and its sensitive host Salmonella potsdam strain 2 (SP2). Calf thymus DNA was used as a control.

Nitrocellulose membranes were used to adsorb varying concentrations of unlabeled DNA, using P4/2 DNA, SP4 DNA, SP2 DNA, and calf thymus DNA. A constant amount of P³² -labeled P4/2 DNA was added to each membrane and the hybrids were allowed to form. After thorough rinsing to get rid of unbound labeled DNA, radioactivity of the samples was read in a liquid …