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Pro-Inflammatory Properties Of Flavobacterium Columnare Cells And Products On Channel Catfish (Ictalurus Punctatus) Neutrophils, Shannon Billings

All Theses

Flavobacterium columnare and Edwardsiella ictaluri are the leading causes for losses in the aquaculture industry. The losses from the diseases caused by these pathogens total $2.5 million for catfish and $100 million for total aquaculture. F. columnare's infection rates and stressors associated with outbreaks have been well-characterized, but the specific inflammatory responses of catfish neutrophils to the bacteria have not been studied. The objective, therefore, was to investigate the pro-inflammatory effects of the outer membrane proteins, extracellular products, and whole live bacteria, heat-killed (HK), and formalin-killed (FK) F. columnare and E. ictaluri to determine the effects on channel catfish phagocyte …

Evolution In Neotropical Herpetofauna: Species Boundaries In High Andean Frogs And Evolutionary Genetics In The Lava Lizard Genus Microlophus (Squamata: Tropiduridae): A History Of Colonization And Dispersal, Edgar Benavides

Theses and Dissertations

In this collection of papers I have summarized my investigations into the field of evolutionary genetics and more specifically into patterns of biodiversity and evolutionary processes. The lizards (and frogs) studied here share common features in that they are largely present in unique environments, which are also regions that are biologically understudied. Most of these taxa show high degrees of endemism, interesting natural history characteristics, and each group manifests distinctive adaptations of general evolutionary interest. My work in the genus Telmatobius has been a progressive approach that began in my MS program, and it first focused on alpha taxonomy, morphological …

Homologous Neurons And Their Locomotor Functions In Nudibranch Molluscs, James M. Newcomb

Biology Dissertations

These studies compare neurotransmitter localization and the behavioral functions of homologous neurons in nudibranch molluscs to determine the types of changes that might underlie the evolution of species-specific behaviors. Serotonin (5-HT) immunohistochemistry in eleven nudibranch species indicated that certain groups of 5 HT-immunoreactive neurons, such as the Cerebral Serotonergic Posterior (CeSP) cluster, are present in all species. However, the locations and numbers of many other 5 HT-immunoreactive neurons were variable. Thus, particular parts of the serotonergic system have changed during the evolution of nudibranchs. To test whether the functions of homologous neurons are phylogenetically variable, comparisons were made in species …

Septal Infusions Of The H-Channel Blocker Zd7288 Impair Spontaneous Alternation But Not Inhibitory Avoidance, Ramata Sissoko Cisse

Biology Theses

It is well established that the septo-hippocampal system is involved in memory. The medial septum is connected to the hippocampus via the fimbria fornix, which consists mostly of acetylcholine and ã-aminobutyric acid (GABA) projection neurons. The contributions of the cholinergic projection to memory have been studied extensively; whereas, the role of the GABAergic projection is not well characterized. The present experiment tested whether septal infusions of the selective H-channel blocker ZD7288 would impair spontaneous alternation (SA) and continuous multiple inhibitory avoidance (CMIA). Fifteen minutes prior to assessing SA or CMIA, different groups of male Sprague-Dawley rats were given septal infusions …

Isolation And Characterization Of The Y32g9a.8 Promoter In C. Elegans, Rebecca Joy Schlisner

Biology Theses

The over-expression of Down syndrome cell adhesion molecules (DSCAMs) is partially responsible for the mental retardation associated with Down syndrome. Previous work in our lab showed that a DSCAM homolog in C. elegans, Y32G9A.8, is expressed at all developmental stages and appears to be crucial for survival. In an effort to map the expression pattern, I used the Genome Sciences Centre’s primer design program (http://elegans.bcgsc.bc.ca/gfp_primers/) to design a GFP promoter fusion product that was used to monitor gene expression. The results indicate that Y32G9A.8 is expressed in the animal’s gut, suggesting that it may function in the worm’s innate immune …

The Role Of S7, A Subunit Of The 19s Proteasome, In The Transcriptional Regulation Of Mhc Ii., Dawson Gerhardt

Biology Theses

Induction of an adaptive, or antigen specific, immune response is critical for eliminating most infections. Pathogen clearance is accomplished primarily, by the actions of CD4+ T cells through their ability to recognize foreign antigens presented at the cell surface by major histocompatibility class II (MHC II) molecules. Consequently, the capacity to regulate expression of MHC molecules is essential to control the adaptive immune response. MHC molecules are regulated at the level of transcription by a master regulator, the class II transcriptional activator, CIITA. Thus, the expression of MHC II is directly related to proper CIITA activity. This thesis focuses on …

An Integrative Analysis Of Reproduction And Stress In Free-Living Male Cottonmouths, Agkistrodon Piscivorus, Sean Patrick Graham

Biology Theses

I conducted an integrative field study on male cottonmouths (Agkistrodon piscivorus), a common pitviper of the southeastern United States, to investigate the evolution of contrasting mating patterns in North American pitvipers (bimodal and unimodal annual patterns) and resolve conflicting information about the pattern exhibited by the cottonmouth. I determined a unimodal late summer peak of testosterone (T) and a muted unimodal seasonal cycle of the sexual segment of the kidney (a secondary sexual characteristic), both of which were correlated with the single peak of spermatogenesis in late summer. I also conducted a study to determine diel and seasonal variation of …

Investigation Into The Mechanism(S) Which Permit The High-Rate, Degradation Of Pahs And Related Petroleum Hydrocarbons In Sequencing Batch Reactors By Attached Cells In A Controlled Mixed Bacterial Community., Emad Ibraheim Hussein

Biology Dissertations

A stable mixed culture, deposited as ATCC 55644, previously shown to degrade petroleum hydrocarbons at relatively high concentrations was used as the source of inoculum. This culture was grown in Stanier’s minimal media, either in the presence of different concentrations of naphthalene, nitrobenzene and toluene (NNT) or naphthalene and toluene (NT) as the sole source of C and/or N. Results showed that the majority of the strains isolated from the mixed culture were able to grow in the presence of NNT or NT. A total of 20 different isolates were isolated from the mixed culture. Individual isolates were grown in …

The Role Of Ecological Interactions In Polymicrobial Biofilms And Their Contribution To Multiple Antibiotic Resistance, Heather Adele O'Connell

Biology Dissertations

The primary objectives of this research were to demonstrate that: 1.) antibiotic resistant bacteria can promote the survival of antibiotic sensitive organisms when grown simultaneously as biofilms in antibiotics, 2.) community-level multiple antibiotic resistance of polymicrobial consortia can lead to biofilm formation despite the presence of multiple antibiotics, and 3.) biofilms may benefit plasmid retention and heterologous protein production in the absence of selective pressure. Quantitative analyses of confocal data showed that ampicillin resistant organisms supported populations of ampicillin sensitive organisms in steady state ampicillin concentrations 13 times greater than that which would inhibit sensitive cells inoculated alone. The rate …

Molecular Screening Of Azoreductase Gene And Its Activity In Human Intestinal Bacteria, Syndia S. Todd

McCabe Thesis Collection

The intestinal microflora are capable of performing a wide variety of metabolic transformations. "The intestinal bacteria can enhance the function of the entire gastrointestinal tract, protect against pathogenic, maintain the vital chemical balance of the gastrointestinal system, and produce needed vitamins and hormones" (http;//www.upwardquest.com/crit2.html). Some of the products of this metabolism have been associated with carcinogenic processes, such as cancer, tumor formation, gastrointestinal disease, and infections. The ability of human intestinal microbes to interact with metabolites directly or after recirculation may contribute toward different toxicological disorders and disease.

The purpose of this study is to characterize and isolate the azoreductase …

Conservation Taxonomy Of The Cuban Parrot: Morphological, Plumage And Flight Call Variation, M. Bryant J. Reynolds

Loma Linda University Electronic Theses, Dissertations & Projects

Conservation taxonomy, the study of organismal classification to clarify conservation priorities, seeks to define species and subspecies limits. Allopatric populations, such as those present on islands, pose special challenges to identifying taxonomic boundaries that can be be addressed using diagnostic criteria. Because some of the island populations of Cuban Parrot (Amazona leucocephala) are highly endangered, the five recognized subspecies need careful reevaluation. I measured 18 morphological and plumage characters from 188 museum specimens representing the six extant and one extirpated island populations. I also examined 11 spectrographic characters from the flight calls of 23 parrots representing all six …

Responses To Salinity Of Color Polymorphs In Two Populations Of The Sea Star, Pisaster Achraceus, Viren Johann Perumal

Loma Linda University Electronic Theses, Dissertations & Projects

Pisaster ochraceus was analyzed to determine if varying salinities, animal color, or location affect the physiology of these sea stars. The three responses analyzed were aerobic respiration, ammonia excretion, and self-righting. The tested variables included two different color morphs (orange and purple) of P. ochraceus, two different locations (open coast and inland straits) in Washington State, and three salinities (22, 30, and 40 psu).

Wet mass-specific oxygen consumption rates were not significantly affected by color, location, or salinity, and Dry mass-specific oxygen consumption rates showed no significant differences for main effects, but a three-way interaction was identified. Similarly, ammonia …

A Quantitative Analysis Of Morphological Changes In Specific Laminae Of The Olfactory Bulb Of Adult Zebrafish Following Peripheral Sensory Deafferentation, Travis L. Devlin

Masters Theses

Permanent removal of the olfactory organ in adult zebrafish has been shown to result in a significant reduction in the total volume of the ipsilateral olfactory bulb. The overall objective of the current project was to investigate the hypothesis that contact between the axons of the olfactory sensory neurons and the olfactory bulb is necessary for the maintenance of the normal post-synaptic organization of the olfactory bulb by quantifying the morphological changes that take place within specific laminae of the olfactory bulb following peripheral deafferentation. Complete, unilateral ablation of the olfactory organ resulted in permanent deafferentation of the ipsilateral olfactory …

Metabolic And Phenotypic Characterization Of Aerobic Pcb Degrading Bacteria Isolated From Kalamazoo River Sediments, Brenton K. Lehmkuhl

Masters Theses

The Kalamazoo River is contaminated with polychlorinated biphenyls (PCBs) which are neurotoxins and suspected carcinogens. The goal of this study was to isolate, identify, and metabolically characterize PCB degrading strains of aerobic bacteria. Biphenyl enrichments resulted in the isolation of putative PCB degrading strains from different locations along the river. Based on 16S rRNA gene analysis the isolated strains were identified as belonging to the genera of Achromobacter, Acidovorax, Cellulosimicrobium, Paenibacillus, Pseudomonas, and Rhodococcus. These strains were screened for their PCB degrading ability and congener specificity. All of the isolated strains degraded PCBs via the 2,3-dioxygenase pathway. The range …

Current And Historical Aquatic Food Webs Of The Middle Rio Grande, Nm, Melanie S. Edwards

Biology ETDs

The Rio Grande has been identified as one of the most endangered rivers in the United States by American Rivers. Biologically, the consequences of the massive anthropogenic alterations of this river have been substantial. The overall aim of this study was to characterize the ecological implications of these alterations in the aquatic food web of the middle Rio Grande (MRG) of New Mexico. Our approach was to analyze the stable isotope composition of current food web components and of historical museum preserved fish specimens. After determining that we could use stable isotope analyses of historical museum preserved fish specimens (chapter …

Neurolipofuscin Is A Measure Of Age In The Caribbean Spiny Lobster, Panulirus Argus, In Florida, Kerry Elizabeth Maxwell

Biology Theses

Accurate age estimates for the commercially-important Caribbean spiny lobster, Panulirus argus, would greatly enhance analyses of life history and population dynamics. Previous estimates of their age based on size and growth may be inaccurate because of variable growth in the wild. An established technique for aging crustaceans – histologically-determined lipofuscin content in the nervous system – was used on lobsters reared in the laboratory for up to five years. We verified the presence of lipofuscin in eyestalk neural tissue and described its distribution in cell cluster A of the hemiellipsoid body. Neurolipofuscin content of both sexes increased linearly over the …

Steroid Sensitive Neurons And Male Rat Mating Behavior, Gloria Gradine Huddleston

Biology Dissertations

Male rat mating is a suite of individual behaviors mediated by the actions of two metabolites of testosterone (T), dihydrotestosterone (DHT) and estradiol (E2), on the brain. Individually, neither metabolite fully maintains or restores mating in castrated males, but both combined are as effective as T. Two hormone-responsive areas of the brain, the medial preoptic area (MPO) and the medial amygdala (MEA), are crucial for mating. These studies ask: by what mechanism(s) does E2 act in the MPO and MEA? We blocked the conversion of T to E2 in the MEA of intact male rats and sexual behavior was not …

Changes In Microbial Community Structure Of Petroleum Contaminated Sediments Are Reflected In Subsurface Geophysical Signatures, Jonathan P. Allen

Masters Theses

Petroleum contamination of sediments leads to dynamic changes in the subsurface. These include changes in the microbiota as well as in the subsurface geophysical and geochemical properties. Anomalously high conductivity values observed in subsurface zones contaminated with light non aqueous phase liquids (LNAPLs) have been suggested to be the result of microbial activity. Therefore, we investigated the interdependence between geoelectrical signatures and microbial community structure in petroleum contaminated field sediments and laboratory column experiments. Spatial and temporal changes in electrical conductivity of the subsurface paralleled changes in microbial community composition, with the highest conductivity values concomitant with specific anaerobic hydrocarbon-degrading …

Identification And Characterization Of Cellular Targets Of The Bacterial Cytotoxin Yopt In Saccharomyces Cerevisiae, Paul David Caccamo

Masters Theses

Human pathogenic Yersinia spp. utilize Type III Secretion to deliver six effector proteins into host cells. The injected proteins resemble eukaryotic signal transduction molecules and are capable of disrupting signaling pathways in order to subvert the functions of the targeted cell or disrupt communication with surrounding cells. As a result, bacterial invaders are not only able to survive the threat of a host immune response, but can thrive despite it. YopT is a cysteine protease that cleaves RhoGTPases, releasing them from the membrane and thus from their role as initiators of signaling pathways, including the nucleation of actin and …

Characterization Of Membrane Potentials In Vascular Smooth Muscle Of Hagfish, Lamprey And Trout, Prentiss Jones Jr.

Dissertations

The objective of this study was to characterize membrane potentials in systemic arteries of Pacific hagfish, Eptatretus stouti, Rainbow trout, Onchorhyncus mykiss, and Sea lamprey Petromyzon marinus. Previous studies have characterized membrane potentials in piscine tissue. However, these studies utilized non-vascular tissues such as cardiac muscle and skeletal muscle (69, 161). Characterization of membrane potentials in fish vasculature is without precedent in the literature. The hypothesis of this study was that membrane potentials in fish vascular smooth muscle differ little between species when comparable vasculature is evaluated.

Chironomid Hemoglobin Genetic Diversity As An Indicator Of The New Jersey Hackensack Meadowlands Wetland Health, Lene Marie De Coursin Jacobs

Seton Hall University Dissertations and Theses (ETDs)

Kearny Marsh located within the Hackensack Meadowlands is a freshwater wetland impacted by multiple environmental stressors from human activity. The marsh is located in the northeastern New Jersey metropolitan area. Chironomid larvae, aquatic larvae of midge fly, were analyzed from two Kearny Marsh sample sites, W9 and W22. A previous sediment analysis and toxicity study characterized heavy metal contaminants the marsh. The data results were applied in this thesis study to determine the correlation between environmental stressors and chironomid genetic diversity. Site W9 sediment was impacted by severe levels of total heavy metal contamination, whereas site W22 had just below …

Genetic Considerations For The Conservation And Management Of Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) In Yellowstone National Park, David J. Janetski

Theses and Dissertations

A key component to conservation is an accurate understanding of genetic subdivision within a species. Despite their ecological and economic importance, relatively little is understood about the genetic structuring of Yellowstone cutthroat trout in Yellowstone National Park. Here, we use traditional (Fst, Rst, Nm, and AMOVA) and modern (Bayesian assignment tests, coalescent theory, and nested clade analysis) analytical approaches to describe the population genetic subdivision of cutthroat trout spawning populations in Yellowstone Lake and to identify genetically distinct population segments throughout Yellowstone National Park. Evidence for restricted gene flow between spawning populations within Yellowstone Lake was detected using nested clade …

Functional Role Of Dead-Box P68 Rna Helicase In Gene Expression, Chunru Lin

Biology Dissertations

How tumor cells migrate and metastasize from primary sites requires four major steps: invasion, intravasation, extravasation and proliferation from micrometastases to malignant tumor. The initiation of tumor cell invasion requires Epithelial-Mesenchymal Transition (EMT), by which tumor cells lose cell-cell interactions and gain the ability of migration. The gene expression profile during the EMT process has been extensively investigated to study the initiation of EMT. In our studies, we indicated that tyrosine phosphorylation of human p68 RNA helicase positively associated with the malignant status of tumor tissue or cells. Studying of this relationship revealed that p68 RNA helicase played a critical …

Identification And Functional Analysis Of Crustacean Serotonin Receptors., Nadja Spitzer

Biology Dissertations

Constantly changing environments force animals to adapt by cycling through multiple physiological states. Plasticity in sensory, motor, and modulatory neural circuits is an essential part of these adaptive processes. Invertebrates with their accessible, identifiable neurons are excellent models for investigating the molecular and cellular mechanisms underlying state-dependent neural plasticity, and provide insight into similar processes in more complex systems. These properties have allowed highly detailed characterization of several crustacean circuits with respect to their connectivities, cellular properties, responses to various inputs, and outputs. Serotonin (5-HT) is an important neuromodulator in virtually every animal species. 5-HT signals are mediated primarily by …

Chemosensory Responses In Azospirillum Brasilense, Bonnie Baggett Stephens

Biology Dissertations

The ability to swim and navigate the surrounding environment confers an advantage to motile bacteria, allowing the occupation of niches that are optimum for survival and growth. Bacteria are too small to sense their environment spatially, so they must sense the environment temporally by comparing the past and present environments and altering their motility accordingly. Chemotaxis systems coordinate flagellar motility responses with temporal sensing of the environment. Chemotaxis is proposed to be involved in plant root colonization by directing soil bacteria toward root exudates of various cereals, promoting growth. The nitrogen-fixing alpha-proteobacterium Azospirillum brasilense utilizes chemotaxis to navigate its environment …

Biogeography Of Buarremon Brush-Finches (Aves, Emberizinae): Integrating Ecology, Evolution, And Systematics, Carlos Daniel Cadena

Dissertations

Ecological and historical approaches to studying species¿ geographic ranges have yet to be unified. Ideal scenarios for integrating ecology with evolutionary biology in biogeography are those where contemporary ecological interactions may have influenced species¿ distributions historically, driving the evolution of ecological niches. I focused on understanding the origin of elevational distributions of species, and specifically on the role of interspecific competition in the origin of complementary elevational ranges. To test hypotheses about the origin of elevational distributions, I followed a combined approach involving molecular phylogenetics, phylogeography, population genetics, and ecological niche modeling. I focused on Buarremon torquatus and B. brunneinucha …

Phylogeographic Analyses Of Obligate And Facultative Cave Crayfish Species On The Cumberland Plateau Of The Southern Appalachians, Jennifer Elizabeth Buhay

Theses and Dissertations

Cave systems and their unique biota are widely viewed as highly endangered, yet very little is known about basic life history, ecology, distributions, habitat requirements, and evolutionary relationships of subterranean species. The crux of the problem in cave studies is the assumption that traditionally defined morpho-species represent distinct evolutionary lineages. Convergence is exhibited in the morphologies of many animal groups, vertebrate and invertebrate, which leads to confusion in diagnosing species' boundaries, geographic distributions, gene flow routes, and imperilment. This dissertation research includes phylogeographic analyses of freshwater cave-dwelling crayfishes in the Southern Appalachians, a global hotspot of subterranean biodiversity. By examining …

Development Of An In Vitro Protocol To Study The Effect Of Estrogen On Osteoblast Activity, Sourik Ganguly

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science & Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Sourik Ganguly on July 7, 2006.

Molecular Analysis Of The Effects Of Atrazine On Xenopus Laevis Frogs, Ronald Edward Celestine

Dissertations

Atrazine, the most commonly used herbicide in the U.S., has been implicated as one of the factors that may be causing the worldwide decline of amphibians. First, I examined effects of atrazine on laboratory raised Xenopus laevis tadpoles, treated from 5 days post fertilization to NF stage 65/66 with a concentrationof 25 ppb of atrazine. This study showed no significant difference in body weight, length and metamorphic rate.

Second, I used DNA microarrays to examine mRNA expression levels of genes in atrazine treated and control Xenopus laevis tadpoles. I found significant changes in gene expression levels of 18 genes. These …

Exposure Of Nervous System Cells To Polychlorinated Biphenyls (Pcbs), Results In Alterations Of Neurotrophic Factor Expression, Gordon H. Gurley

Dissertations

Toxic insult by PCBs results in learning and memory deficits in humans. Alterations in expression of neurotrophic factors (NF) and/or their receptors have been linked to changes in learning and memory. How PCBs affect cognition is not known. We suggest that PCBs affect cognition by altering NF expression.

We exposed cultured C6 rat glioblastoma cells (an astrocyte cell-line) to medium containing PCB (Aroclor 1254 (10ppm)). Control cells were treated with dimethyl sulfoxide (DMSO) or regular medium. Enzyme-linked immunosorbent assays (ELISA) were used to determine glial cell-line derived neurotrophic factor(GDNF) and nerve growth factor (NGF) concentrations in all samples. We also …