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Targeted Gene Replacement To Mimic Familial Hypertrophic Cardiomyopathy In Caenorhabditis Elegans, Craig Alan Almeida

Doctoral Dissertations

The identification in invertebrates of genes homologous to human disease genes provides the possibility to broaden the spectrum of model organisms to include experimental invertebrates. The goal of this study is to test the possibility of using Caenorhabditis elegans as an animal model for the inherited human heart disorder familial hypertrophic cardiomyopathy. In 10-30% of the affected families that have been studied, this disease is caused by mutations in the $\beta$-cardiac myosin heavy chain (MHC) gene. The most common of these mutations results in the replacement of an evolutionarily conserved arginine residue (R403) with glutamine (R403Q). While this information has …

The Effects Of Primary Olfactory Cortical And Thalamic Lesions On Olfactory Continuous Non-Matching To Sample And Discrimination In The Rat, Yueping Zhang

Doctoral Dissertations

Forty-two male rats were pretrained on the olfactory continuous delayed non-matching to sample (CDNMTS) task. They were then matched for performance and randomly assigned to one of the following six treatment groups: excitotoxic lesions of pyriform cortex, later entorhinal cortex, lateral internal medullary lamina (L-IML), mediodorsal nucleus (MDn), nonspecific nuclei, and sham control. After recovery from surgery, the rats were retrained on the olfactory CDNMTS. Delay effects were examined by manipulating retention intervals (RI), with five RIs (4, 6, 9, 13.5, and 20.25 s) randomly mixed within each session. The number of odor stimuli used in each session varied from …

The Purification And Characterization Of An Extrapallial Fluid Protein From The Mollusc, Mytilus Edulis, Stephen Joseph Hattan

Doctoral Dissertations

Shell deposition within the bivalve mollusc Mytilus edulis is regulated by the macromolecules of the extrapallial fluid (EP fluid). These mineralization regulating macromolecules are thought to be responsible for the nucleation, growth regulation and growth cessation of the CaCO$\sb3$ mineral crystals that will inevitable constitute $\geq$95% of the mature shell.

This dissertation presents the results of the purification and characterization of the major EP fluid protein of the bivalve Mytilus edulis. The major EP fluid protein was determined to comprise 56% of the total fluid protein and to consist of 7.25% by weight carbohydrate. The protein was purified though a …

Variation In Transposable Element Sequence And Activity In The Nematode Caenorhabditis Elegans, Jeremy David Glasner

Doctoral Dissertations

Eukaryotic genomes are replete with transposable elements. The nematode C. elegans will be the first multicellular organism to have its genome completely sequenced. This sequence will allow identification of all the transposon and transposon-related sequences from a single genome. In anticipation of the complete genome sequence I have initiated a series of analyses of sequences from the C. elegans genome database that share significant similarity to known families of transposons. Several members of known transposon families were observed along with a plethora of sequences related to these known transposons. Cladistic analyses were used to describe the relationships among transposons and …

Life History And Reproductive Biology Of The Estuarine Nudibranch Tenellia Adspersa (Nordmann, 1845), Charles Morgan Chester

Doctoral Dissertations

Tenellia adspersa is a small (5-7 mm) estuarine nudibranch. Tenellia lives in a highly variable environment and feeds on many gymnoblastic and calyptoblastic hydroids. I undertook a field study at four sites in the Great Bay Estuary (Durham, New Hampshire) to assess the amount of variability in abiotic and biotic factors. Environmental parameters (temperature and salinity) and the availability of hydroid prey (Cordyolophora lacustris and Obelia spp.) varied within the generation time of Tenellia and could affect its life history.

Laboratory studies compared the growth rate of the hydroid, Cordylophora to the growth rate and predation rate of Tenellia. The …

Patterns Of Base Composition Within And Between Animal Mitochondrial Genomes, Nicole T. Perna

Doctoral Dissertations

Nucleotide composition of a DNA molecule is a product of base substitution. Variation in nucleotide composition indicates a change in the pattern of substitution at either the level of the underlying mutational spectrum or the constraints imposed by natural selection. This work explores patterns of nucleotide usage within and between animal mitochondrial genomes and the evolutionary mechanisms that have shaped these patterns. Fourfold degenerate sites are expected to reflect the underlying mutational spectrum. Three simple measures of compositional bias, taking into account the strand-specific nature of nucleotide distribution in mtDNA, reveal considerable variation among fourfold degenerate sites of metazoan mitochondrial …

The Potential For Ontogenetic Vertical Migration By Larvae Of Bathyal Echinoderms, William Jaeckle, Craig M. Young, Michael G. Devin, Suki U.K. Ekaratne, Sophie B. George

Scholarship

Planktotrophy is a relatively common developmental mode among bathyal and abyssal echinoderms, but the sources of food used by deep-sea planktotrophic larvae remain generally unknown. Very few deep-sea echinoderm larvae have been collected in plankton samples, so we do not know whether larvae migrate to the euphotic zone to feed or if they rely on bacteria or detritus at greater depths. We approached this question indirectly by investigating whether larvae of bathyal echinoids can tolerate the temperatures they would encounter in the euphotic zone and whether they possess sufficient energy stores to migrate to the euphotic zone without feeding. Twenty-four …

Spatial Distribution And Sequential Sampling Of The Rice Water Weevil, Lissorhoptrus Oryzophilus Kuschel, In Louisiana., Mark Alan Muegge

LSU Historical Dissertations and Theses

Studies were conducted in Louisiana to determine the spatial and temporal distribution of rice water weevil (RWW), Lissorhoptrus oryzophilus Kuschel, adults, eggs, larvae and pupae in drill-seeded rice. In addition, three sequential sampling plans, Kuno's fixed precision sequential sampling plan, the sequential probability ratio test (SPRT), and 2-SPRT, were developed and evaluated to establish an accurate and economically efficient sampling plan for RWW larvae in drill-seeded rice in Louisiana. Values obtained for the aggregation indices, b, from Taylor's power law, $\beta$, from Iwao's patchiness regression and, k, from the negative binomial distribution indicated that RWW larvae were nearly randomly distributed …

Interaction Between Ap-1 Proteins And Glucocorticoid Receptors In Regulation Of Lymphokine Activated Killer (Lak) Cell Activity In The Equine Species., Jing Bu

LSU Historical Dissertations and Theses

This project was performed in order to determine whether exercise-induced increases in plasma cortisol concentrations may be responsible for enhanced lymphokine activated killer (LAK) cell activity. Secondly, this project included preliminary experments which were designed to test the hypothesis that stimulatory effects of cortisol on LAK cell activity may be due to cross-talk between signalling systems important to glucocorticoid effects and stimuli which act through nuclear activator protein-1 (AP-1). Blood samples were collected from resting horses in order to determine whether the animals had normal plasma glucocorticoid concentrations. All horses included in these experiments had $10\sp{-7}$ to $10\sp{-8}$M cortisol concentrations …

Relationship Of Catecholamines And Glucocorticoids To Lymphoproliferation Of Equine Peripheral Blood Mononuclear Cells., Lavanya Potla

LSU Historical Dissertations and Theses

Stress has been related to increased plasma epinephrine (E), norepinephrine (NE), and glucocorticoids. These compounds produce immunomodulatory effects by interacting with hormone receptors on or in various immune cells. This project assessed the effects of stress on equine influenza virus (EIV)-specific and mitogen-induced lymphoproliferation of peripheral blood mononuclear cells (PBMCs) in relation to stress-induced changes in E, NE, and cortisol. In vitro effects of amines on proliferative responses and glucocorticoid receptor (GR) assays were done as a secondary measure of hormone and neurotransmitter interactions with the immune system. Time-dependent, saturable-specific hormone binding to GRs was abolished by heat treatment and …

Regulation Of Interrenal Steroidogenesis In Elasmobranchs., Brian Scott Nunez

LSU Historical Dissertations and Theses

This study investigated the steroidogenic enzymes of the elasmobranch interrenal. First, biochemical characteristics of cytochrome P450c21 hydroxylase (P450c21) and 3$\beta$-hydroxysteroid dehydrogenase (3$\beta$-HSD) were determined with incubations of the microsomal fraction of Carcharhinus limbatus (blacktip shark) interrenal tissue. Second, molecular reagents were obtained by isolating and sequencing partial cDNA clones encoding the elasmobranch steroidogenic enzymes cytochrome P450 side chain cleavage (P450scc) and 3$\beta$-HSD from blacktip shark and Daysatis americana (southern stingray) interrenal. Finally, the regulation of Daysatis sabina (Atlantic stingray) interrenal steroidogenesis by peptide hormones such as corticotropin (ACTH) and angiotensin II was investigated by in vitro incubations of interrenal tissue. …

Ion Transport In The Freshwater Bivalve, Corbicula Fluminea (Muller)., Huiyuan Zheng

LSU Historical Dissertations and Theses

Corbicula fluminea (Muller) maintains hydromineral balance in dilute media by active transepithelial transport of Na and Cl. Cl uptake depended on external (Cl) and displayed saturable kinetics. The transport capacity in pondwater(PW)-acclimated animals was 7.00 $\pm$ 0.51 $\mu$eq(g dry tissue $\cdot$ h)$\sp{-1}$ and the transport affinity 0.21 $\pm$ 0.08 mM. Prolonged salt depletion increased Cl transport capacity without changing the affinity. In PW-acclimated C. fluminea, Na and Cl transport were independent, and were stimulated by serotonin. In salt depleted (SD)animals, Na transport was partially Cl-dependent but Cl transport was Na-independent. Acetazolamide increased Na and Cl efflux. Both serotonin and acetazolamide …

Expression Of A Designed Cecropin Analog Gene Using A Baculovirus Vector., Kyusam Choi

LSU Historical Dissertations and Theses

Cecropins are basic, amphipathic peptides with antibacterial activity against many Gram-positive and Gram-negative bacteria. By retaining the positively charged, amphipathic characteristic of cecropin B, a cecropin analog S1, in which 54% of amino acid residues were substituted, was synthesized and shown to possess a broad spectrum of antimicrobial activity. To determine expression of the cecropin analog S1 in Sf9 cells, two gene constructs were designed, and inserted into Autographa californica nuclear polyhedrosis virus under the control of the polyhedrin promoter. One construct, pBS1, consisted of a gene encoding the analog peptide, so that the gene was intended for expression in …

Paleoindicators Of Changing Water Conditions In Louisiana Estuaries., Michael Lewis Parsons

LSU Historical Dissertations and Theses

Sediment cores were collected to study the development of eutrophication and hydrological changes in coastal Louisiana. The cores were taken at marsh sites hypothesized to be influenced primarily by riverine inputs (Fourleague Bay-FLB), localized activities (Terrebonne Bay-TSMP), and both riverine and localized processes (Airplane Lake-APL). The sediment cores represented time frames ranging from 330 years (APL) to 70 years (TSMP) BP according to core dating results. Sediment core samples were analyzed for diatoms, other microfossils, pigments, biogenic silica, and sediment characteristics. Additionally, land use records were utilized as a proxy of anthropogenic activities, and to aid in the interpretation of …

Cloning, Sequencing And Regulation Of The Rhodobacter Capsulatusheme Gene., Georgia Ineichen

LSU Historical Dissertations and Theses

In Rhodobacter capsulatus, a purple nonsulfur bacterium, the tetrapyrrole pathway yields four end products: siroheme, vitamin B12, heme and bacteriochlorophyll. Growth of R. capsulatus under low oxygen tension increases carbon flow through the tetrapyrrole pathway up to 100 fold. The mechanism(s) for this regulation is currently unknown. One regulatory mechanism could be transcriptional control of one or more of the genes in the common portion of the tetrapyrrole pathway. The fifth gene in the pathway, hemE, has been cloned by complementation of an Escherichia coli hemE::miniTn10 mutant. Sequence data of hemE revealed the presence of an upstream palindrome that is …

Importance Of A Siderophore In The Pathogenesis And Virulence Of Photobacterium Damsela Subsp. Piscicida In Hybrid Striped Bass (Morone Saxatili X Morone Chrysops)., John Phillip Hawke

LSU Historical Dissertations and Theses

Photobacterium damsela subsp. piscicida, formerly Pasteurella piscicida, is an important new pathogen of hybrid striped bass cultured in brackish water on Louisiana mariculture farms. Louisiana isolates compared with strains of P. damsela subsp. piscicida from Greece, Japan, Israel and Chesapeake Bay, USA and were found to be identical in biochemical phenotype and enzymic activity. Small plasmids of 8 and 5 kb were unique to Louisiana strains. Sequential daily bacteriology and histopathology on hybrid striped bass experimentally infected by immersion revealed that following high doses (13,000 CFU/ml) the gills and spleen are colonized first as early as 24 hours PI, followed …

Experimental Lymphatic Filariasis In Gerbils (Meriones Unguiculatus): Molecular Cloning And Expression Of Gerbil Cytokines And Measurement Of Cytokine Gene Expression During A Primary Infection Of Brugia Pahangi., Zhiming Mai

LSU Historical Dissertations and Theses

Cytokines play an important role in regulation of T cell responses. Two T helper cell subsets have been identified in some species and are defined by their cytokine secretion profiles. Th1 cells produce IL-2 and IFN-$\gamma,$ whereas Th2 cells express IL-4, IL-5, and IL-10. Precursor T cells that express a mixture of these cytokines are considered Th0 cells. It is hypothesized that primary infections of Brugia pahangi in gerbils induce an initial Th0 or Th1 like response which with time becomes a Th2 like response. To test this dynamic parasitism induced shift in cytokine profile, it is necessary to measure …

The Association Between Chronic Aerobic Activity And Heart Rate Variability In Patients With Coronary Artery Disease., Robert Howard Wood

LSU Historical Dissertations and Theses

Poor heart rate variability (HRV) among patients with coronary artery disease (CAD) is predictive of future incidence of sudden arrhythmic and all-cause death. Furthermore, mental stress appears to further depress HRV in these patients. Chronic aerobic activity level appears to be positively related to HRV among the general population; however, the extent to which this relationship exists among patients with CAD is not clear. Therefore, this study investigated the association between level of chronic aerobic activity and HRV among CAD patients during conditions of paced respiratory control and during the Stroop Color-Word Conflict Test (CWCT). CAD patients were assigned to …

Microsatellite-Based Paternity Analysis In Hexaploid Sweetpotato (Ipomoea Batatas (L.) Lam.)., Mario Ignacio Buteler

LSU Historical Dissertations and Theses

The use of genetic markers for paternity identification was investigated in hexaploid sweetpotato. Traditional sweetpotato breeding relies on the open pollination of numerous parents and the visual selection of progeny. Previous empirical and theoretical evidence shows this type of breeding system is extremely inefficient. Typically, only a few of these maternal parents routinely produce superior progeny. A similar scenario exists for the paternal parent. Identifying specific parental combinations which produce superior progeny would improve breeding efficiency, hence the need to identify paternity in superior progeny. A computer simulation study established the minimum number of alleles and loci required for paternity …

Movements, Habitat Use, And Survival Of Female Northern Pintails In Southwestern Louisiana., Robert Ripley Cox Jr

LSU Historical Dissertations and Theses

I developed portable platforms for setting rocket nets in open-water habitats, and used them to capture 1116 waterfowl of 7 species during winters 1991-92 and 1992-93 in southwestern Louisiana. Distance and duration of evening flights of female northern pintails (Anas acuta; hereafter pintails) from Lacassine National Wildlife Refuge increased with date within wintering period, and generally were greater than previously reported estimates for wintering waterfowl. I found that diurnal use of refuges by females increased during hunting seasons, contradicting Tamisier's hypothesis that use of refuges by pintails in southwestern Louisiana is not influenced by hunting. Female pintails extensively used privately …

Cytogenetic And Molecular Analysis Of The Channel Catfish (Ictalurus Punctatus) Genome., Quiyang Zhang

LSU Historical Dissertations and Theses

This research presents studies on cytogenetics and molecular genetics of channel catfish (Ictalurus punctatus), the most important fish species cultured in the United States. The goals of this project were to analyze the genome of the channel catfish and to develop a direct method of mapping single-locus genes. A series of techniques were developed to facilitate these studies, including culture of fibroblast cells, preparation of chromosomes from catfish of different ages, staining for nucleolus organizer regions (NOR) and heterochromatin (C-banding), restriction enzyme banding, replication R-banding, simultaneous detection of sister-chromatid exchange (SCE) and C-banding, fluorescent in-situ hybridization (FISH) and indirect and …

Molecular Systematics Of Red Algae., Jeffrey Craig Bailey

LSU Historical Dissertations and Theses

Phylogenetic analyses of nucleotide sequences for the nuclear-encoded small subunit ribosomal RNA (SSU) gene were used to test current hypotheses of relationships within the Corallinales and among the florideophycidaean orders of red algae. Analyses of SSU gene sequences indicate that the order Corallinales includes four major lineages. The Sporolithaceae is resolved as the earliest-diverging lineage within the order and forms the sister group to a monophyletic Corallinaceae. The molecular data also support the monophyly of the subfamilies Melobesioideae and Corallinoideae. The latter subfamily is inferred as sister to a fourth lineage including non-geniculate and geniculate species classified in the subfamilies …

Analysis Of Host-Parasite Cospeciation: Effects Of Spatial And Temporal Scale., James W. Demastes

LSU Historical Dissertations and Theses

All species of pocket gophers (Geomyidae) are parasitized by at least one species of chewing louse (Trichodectidae), and recent genetic studies have demonstrated that a pattern of cospeciation exists between these hosts and parasites (Hafner and Nadler, 1988; Hafner et al., 1994). Little work has been done on this host-parasite system at lower taxonomic (intrageneric) levels. Although cospeciation is evident in a study of pocket gophers within the genus Geomys and their chewing lice (Geomydoecus), reticulate evolution and retention of ancestral lineages obscure the pattern (Chapter 2). One key to understanding how these patterns of cospeciation are produced and how …

Foraging Behavior And Habitat Selection Of Insectivorous Migratory Songbirds At Gulf Coast Stopover Sites In Spring., Chao-Chieh Chen

LSU Historical Dissertations and Theses

Abundance of some species of Nearctic-Neotropical migrants has been declining dramatically since 1970. Most literature about Neotropical migrants is from the breeding grounds, and some is from the wintering grounds; very little is from stopover sites. I studied foraging behavior and habitat selection of insectivorous migratory songbirds at three stopover sites along northern coast of the Gulf of Mexico during spring migrations of 1993-1995. Each migrant species had its unique combination of foraging behavior and habitat use during stopover. Migrants selected certain habitat strata and plant species and avoided others. The decrease of understory vegetation in the reduced plots had …

Physical And Functional Characterization Of Long Terminal Repeat Of Equine Infectious Anemia Virus., Soo Ho Kim

LSU Historical Dissertations and Theses

The U3 region of long terminal repeat (LTR) of equine infectious anemia virus (EIAV) contains transcriptional regulatory elements. To identify the elements in prototype (P), fetal donkey dermal cell-adapted (A), and two variant (V) EIAV LTRs, DNase I footprinting, gel shift, and transient gene expression assays were performed. The assays used U937 monocytic cells which can be induced into macrophages by 12-O-tetradecanoylphorbol-13-acetate (TPA). For study of AP1 sites, c-Jun/AP1 was also used. Footprinting with nuclear extracts from TPA-induced and uninduced U937 cells localized methylated DNA-binding protein (MDBP), PEA2, AP1, PU.1, and CCAAT enhancer-binding protein (C/EBP) sites as common elements in …

Impacts Of Fire And Vertebrate Herbivores On Plant Community Characteristics And Soil Processes In A Coastal Marsh Of Eastern Louisiana, United States Of America., Mark Alan Ford

LSU Historical Dissertations and Theses

Both vertebrate herbivores and fire have long been known to have dramatic and important effects on wetlands. In the first part of this study, conducted in the Pearl River Basin coastal marshes of Louisiana, the interaction between the effects of mammalian herbivores, especially nutria and wild boar, and fire was examined in three marsh community types: those dominated by Sagittaria lancifolia, Panicum virgatum, or Spartina patens/Scirpus americanus. Overall, above-ground biomass was reduced by burning but increased by fencing. Richness only increased in plots that were both burned and fenced. In the three communities, only Scirpus americanus cover was enhanced by …

Relationships Between Brain Biogenic Amines And Reproductive And Defense Behavior In Honey Bees (Apis Mellifera L.)., Jeffrey Wayne Harris

LSU Historical Dissertations and Theses

This dissertation represents an attempt to relate behavioral states of worker honey bees to brain levels of biogenic amines. The first chapter describes the results of experiments which indicated that brain levels of octopamine, dopamine and serotonin were affected by factors including the degree of handling stress, worker age, season of sampling and the source colony from which the workers were sampled. These results helped shape the methods employed in the subsequent chapters. The second and third chapters relate changes in brain dopamine levels to worker honey bee ovarian development. In particular, chapter II showed that an increase in brain …

Postexercise Hypotension (Peh) In The Dog: Possible Role Of Immune System Cytokines., Gerald Dwayne Thompson

LSU Historical Dissertations and Theses

This study investigated postexercise hypotension (PEH) in five normotensive dogs testing these hypotheses: (1) PEH is present in the dog model; (2) high intensity exercise of 85% HR$\rm\sb{max}$ as compared to moderate intensity exercise of 60% HR$\rm\sb{max}$ induces a greater PEH; and (3) IL-1 and its activation of PGE$\sb2$ are associated with PEH. In experiment I, it was found that 85% HR$\rm\sb{max}$ exercise decreased systolic blood pressure (SBP) and mean arterial blood pressure (MABP) at 30 and 60 minutes postexercise (p $<$ 0.05). Both IL-1 and PGE$\sb2$ increased immediately following intense exercise, although temporal patterns were dissimilar. During non-exercise infusion of ibuprofen or dexamethasone (experiment II), blood pressure was not affected, but ibuprofen led to an overall inhibition of PGE$\sb2$. However, dexamethasone infusion led to a significant increase in PGE$\sb2$ at 180 and 210 minutes postinfusion. In experiment IIIA, after intense exercise following ibuprofen or saline infusion, PGE$\sb2$ increased at 120 to 180 minutes postexercise. Similar results were noted after exercise during dexamethasone treatment (experiment IIIB). In experiment IIIA & B, neither ibuprofen nor dexamethasone significantly affected PEH, although non-significant reductions in PEH was observed in dexamethasone treated animals. However, PGE$\sb2$ significantly increased after exercise at time points when PEH was not observed. These data indicate that (1) the intensity of exercise may have an effect on PEH, (2) there is partial support for the involvement of IL-1 and PGE$\sb2$ in PEH due to their immediate increase after exercise although a direct relationship was not observed, and (3) IL-1 still remains a possible mechanism responsible for PEH because of trends for attenuated PEH and PGE$\sb2$ responses following dexamethasone treatment.

Biochemical And Biophysical Studies Of Wild-Type And Active-Site Mutants Of Human Adenosine Deaminase., Qing Zeng

LSU Historical Dissertations and Theses

The focus of this work is structural and functional studies of wild-type and active-site mutants of human adenosine deaminase. Two active-site amino acids, Glu217 and His238, were previously substituted with alanine by site-directed mutagenesis. The Glu217Ala and His238Ala mutants showed little or no changes in Zn content and $\rm K\sb{m}$ value, yet dramatic loss of enzyme activity. Circular dichroism studies of the solution conformation of wild-type and mutant human adenosine deaminases indicate that 30 to 50% of $\alpha$-helical structure is lost in Glu217Ala and His238Ala, respectively, whereas $\beta$-sheet structure is fully retained. Inhibitor binding is measured by a fluorescent assay. …

Toxicity Of Polycyclic Aromatic Hydrocarbons To Benthic Invertebrates., Guilherme R. Lotufo

LSU Historical Dissertations and Theses

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants in aquatic environments. Because of their hydrophobicity, PAHs accumulate in bed sediments and pose a risk to the benthos. Information on the toxicity of sediment-associated PAHs is, however, limited and more information is needed to improve sediment quality-criteria and ecological-risk assessments. My research focused on improving our current knowledge of the acute and, especially, the sublethal effects of sediment-associated PAHs to aquatic invertebrates. Representatives of two phylogenetically distinct benthic invertebrate groups, freshwater tubificid oligochaetes and estuarine meiobenthic harpacticoid copepods, were used. Organisms were exposed to a range of concentrations of sediment-amended contaminants in …