Life Sciences Commons^™

Characterization Of Cytidylyltransferase Enzyme Activity Through High Performance Liquid Chromatography, James Brault

Theses and Dissertations

The cytidylyltransferases are a family of enzymes that utilize cytidine 5â?? triphosphate (CTP) to synthesize molecules that are precursors to membrane phospholipids. There are four well known enzymes: CTP: phosphoethanolamine cytidylyltransferase (ECT), CTP: glycerol-3-phosphate cytidylyltransferase (GCT), 2-C-methyl-D-erythritol-4-phosphate cytidylyltransferase synthetase (CMS), and CTP: phosphocholine cytidylyltransferase (CCT). Previously, a radioisotope tagging method was employed to study cytidylyltransferase catalysis. Using CCT as a model, a method utilizing high performance liquid chromatography (HPLC) was developed to replace the radioisotope scintillation technique. The development of this new HPLC method is cheaper, more efficient, and more accurate than the previously established method.

The targets of separation …

Establishing The Microcrustacean Daphnia As A Model System For Research On Aging, Charles Andrew Shumpert

Theses and Dissertations

Aging is a ubiquitous process pertaining to all biological systems around the planet. Although much has been learned from studies so far on the molecular mechanisms that lead to aging, a complete understanding of a healthy life span and longevity still eludes us. In this dissertation, we will examine the use of a freshwater microcrustacean Daphnia as a model system for studies on the biology of aging. The Introduction chapter presents a review of the general molecular alterations associated with cellular and organismal aging, and discusses the core model organisms currently used to study the aging process. The introduction chapter …

Regulation Of Stress Response And Innate Immunity By DsRna-Binding Proteins Pact And Trbp, Lauren S. Vaughn

Theses and Dissertations

An integral aspect of innate immune response to viral infections is the ability to detect non-self molecules to initiate antiviral signaling via pattern recognition receptors (PRRs). One subset of these receptors are cytoplasmic receptors that contain double stranded (dsRNA) binding domains, which allow them to identify non-self dsRNA produced during a viral infection and mount a protective cellular response. PKR is a dsRNA-activated eIF2α kinase that is a key regulator of cellular antiviral and stress response pathways. Activation of PKR’s catalytic activity requires binding to one of its activators, viral dsRNAs or the cellular protein PACT (PKR activator). Although PACT …

Viruses And Metals In Ocean Food Webs: Top-Down And Bottom-Up Effects Of Marine Viruses And Trace Elements On Marine Picophytoplankton, Brady Robert Cunningham

Theses and Dissertations

Viruses are the most numerous biological entities in the ocean, playing a key role in microbial ecology and biogeochemical cycling. In order to replicate, viruses must first infect a host and then use the host’s cellular machinery to produce new viral particles. Some of the most abundant viral hosts in the subtropical open ocean are picophytoplankton. However, picophytoplankton growth is typically constrained by nutrient availability. In many regions of the ocean, iron (Fe) is only available in very low concentrations causing growth-limitation of picophytoplankton. Interestingly, the interactions between Fe-limitation and viral infection of picophytoplankton have not been extensively studied. This …

Global Methylation Of Dna Among Spartina Alterniflora Clones Differing In Age At North Inlet, Sc, Trenton Agrelius

Theses and Dissertations

“Brown marsh” or “sudden marsh dieback” refers to the rapid death of patches varying in size of Spartina alterniflora. In 2000 following a 100-year record drought, approximately 8,000 hectares of S. alterniflora died along the Louisiana coast, which prompted Louisiana Governor Foster to declare a state of emergency. Other cases have been documented at North Inlet, SC as well as various other marshes along the southeastern United States. Currently, there is much dispute regarding the cause of “sudden marsh dieback” but environmental stress is one of the acknowledged constants across sites. We hypothesized an alternative mechanism in which methylation of …

The Effects Of Elevated Circulating Levels Of Lipocalin 2 On Liver Metastasis Of Colorectal Cancer, John Gerard Bonapart

Theses and Dissertations

In the United States, colorectal cancer (CRC) is the third most diagnosed cancer and the second leading cause of cancer deaths. In 2015, approximately 143,000 new cases will be diagnosed and 50,000 deaths are predicted. Liver metastasis is the major cause of death. To understand the molecular and cellular mechanisms of liver metastasis, we used an orthotopic mouse model of CRC liver metastasis that recapitulated all stages of tumor growth and metastasis to perform whole genome microarray analysis to identify genetic changes in the liver microenvironment in response to primary tumor growth in the cecum. We identified lipocalin 2 (Lcn2) …

Vulnerable Species In A Changing Climate: The Genomic Response Of Antarctic Notothenioid Fishes To Predicted Oceanic Conditions As A Model Of Physiological Plasticity And Adaptive Capability, Troy James Huth

Theses and Dissertations

In its fifth report in 2014 the IPCC reinforced the contribution of anthropogenic CO2 to global climate change predicting widespread and significant changes to the global climate over a relatively short time scale. The polar regions, including the Southern Ocean surrounding Antarctica, were identified as ecosystems that may experience the most rapid and severe changes. As the Southern Ocean is one of the coldest and most oceanographically stable regions on earth, the endemic fauna likely have no alternative habitats available for migration. Further compounding the challenge these species will face is the substantial degree of adaptation to the extreme cold …

Training A New Trick Using No-Reward Markers: Effects On Dogs’ Performance And Stress Behaviors, Naomi Rotenberg

Theses and Dissertations

This study explored using no-reward markers (NRMs). Dogs were taught a novel trick. In the IG group dogs’ errors were ignored; in the NRM group they elicited a tone. Performance and stress were evaluated. IG dogs reached higher levels of performance, with no difference in the frequency of stress behaviors.

Reaction Of Zinc Proteome With Biologically Important Metal Binding Ligands, Kaniz Fatema

Theses and Dissertations

Fluorescent sensors have been widely used as microscopic tools to image Zn2+ on a cellular level. Recently, it has been established that the sensors TSQ and Zinquin form adducts with Zn-proteins and image fractions of the Zn-proteome.1 Since TSQ and Zinquin bind specifically to many Zn-proteins, it is hypothesized that other metal binding ligands, both synthetic and natural, may also bind to the Zn-proteome. Biologically active 1,10-phenanthroline (Phen) and related molecules were investigated for their ability to bind to Zn-proteome. Similarly, the cellular tripeptide, glutathione was investigated. It was observed that Phen and some other metal binding, bidentate ligands, were …

Arylboronates As H2o2 Or Photo-Inducible Dna Cross-Linking Agents: Design, Synthesis, Mechanism, And Anticancer Activity, Yibin Wang

Theses and Dissertations

Interest in the development of cancer therapies with improved selectivity and reduced host toxicity has been growing. In this thesis, we designed and synthesized a series of novel non-toxic arylboronic ester and biarylboronic ester derivatives that can be activated by hydrogen peroxide (H2O2) to induce DNA interstrand cross-link formation. The mechanism of DNA cross-linking induced by these arylboronates involves generation of phenol intermediates 1 followed by departure of leaving group (L) leading to quinone methides (QMs) 2, which directly cross-link DNA via alkylation. The QM formation is the rate-determining step for DNA cross-linking. The activity and selectivity of these compounds …

Transport Mechanisms For Human Fecal Indicator Bacteria In An Urban Stormwater Basin In Southeastern Wisconsin, Chelsea M. Corson

Theses and Dissertations

Discharge of stormwater runoff to receiving waters is a known source of human pathogens; however the primary mechanisms by which these pathogens enter the stormwater system have yet to be quantified. This study builds upon and utilizes prior research findings in an attempt to explain the influence of the age of the pipes within stormwater and sanitary conveyance systems, rainfall and hydrogeological characteristics, and select infrastructure variables that contribute to the observed contamination of an urban stormwater basin in Southeastern Wisconsin.

Over the course of approximately two years from 2012 to 2014, a total of 260 samples from 22 stormwater …

The Mixing Of A River Into Coastal Waters At Two Beaches: Environmental Factors, E. Coli Contributions And Applications For Predictive Models, Adrian Jordan Koski

Theses and Dissertations

Beach closures and public health protection are confounded by analytical procedures that result in delays in notification of adverse water quality conditions and the lack of affordable analytical methods to identify pollutant sources. Attempts have been made to develop predictive frameworks using ancillary hydrometeorological data to statistically anticipate deteriorated water quality. Many urban coastal beaches are impacted by river runoff. In Kenosha Wisconsin, beach sanitary survey data from two beaches adjacent to the mouth of the Pike River were examined to ascertain whether simple river-lake mixing models identified river influence on coastal water quality and improved predictions of beach advisories. …

Functionally Distinct Pools Of Calcineurin Contribute To Depotentiation-Like Synaptic Changes In The Lateral Amygdala During Auditory Fear Extinction, Elena Kay Rotondo

Theses and Dissertations

Until recently, auditory fear extinction was not thought to modify substrates involved in the storage of the original auditory fear memory. Evidence now suggests that extinction results in the reversal of the fear conditioning-induced potentiation of thalamic inputs to the lateral amygdala. However, little is known about the molecular mechanisms that support this depotentiation of synaptic strength. Here we present behavioral and molecular evidence in support of the contribution of two distinct pools of the protein phosphatase calcineurin to depotentiation-like changes in lateral amygdala AMPA receptor trafficking during auditory fear extinction. Calcineurin protein that exists prior to the onset of …

Iodine-131: Measurement And Application Of A Novel Tracer In Lake Michigan, Michael Patrick Montenero

Theses and Dissertations

Iodine-131 is a short-lived (half-life=8.0233 days), gamma emitting, radiopharmaceutical that, when excreted by patients, enters aquatic systems via sewage effluent discharged from water reclamation facilities (WRFs). Here, I report on 131I activities in the nearshore of southwest Lake Michigan in the vicinity of Milwaukee, Wisconsin. This is the first report on 131I activity in any of the Great Lakes of North America.

The flux of 131I from Milwaukee’s two WRFs was monitored from July 2013 to December 2014. Mean discharge of 131I from the Jones Island WRF was (0.664 ± 0.012)×108 Bq d-1 (mean effluent 131I activity: ~0.25 Bq L-1; …

The Identification And Quantification Of Sewage Contamination In The Milwaukee Estuary, Hayley Templar

Theses and Dissertations

Sewage contamination from failing infrastructure and sewer overflows is a major environmental and human health concern in waterways, especially in urban communities bordering the Great Lakes such as Milwaukee, Wisconsin. Culture-based fecal indicator bacteria, such as Escherichia coli, enterococci, and fecal coliforms are traditionally used to indicate the presence of a human health risk due to fecal contamination. These indicators, however, fail to distinguish between sources of fecal contamination (human vs. non-human). Two human-specific fecal indicators, human Bacteroides and human Lachnospiraceae, were used to identify and quantify sewage contamination in the Milwaukee estuary, which discharges to Lake Michigan, as well …

Upper Extremity Kinematic And Kinetic Comparison Of Anterior Versus Posterior Walkers During Functional Activities In Children With Cerebral Palsy, Chris Burckardt

Theses and Dissertations

Introduction: Investigating the differences in upper extremity (UE) joint biomechanics between anterior and posterior walkers has been explored in limited contexts, even though research has shown that prolonged use of walking aids can lead to UE joint weakening or musculoskeletal injuries. Recent studies have investigated some of these differences in children with spastic diplegic cerebral palsy (CP) during gait; however, no research has been conducted that compare these UE joint biomechanical differences during functional activities or activities of daily living (ADLs). The aim of this study is to use motion analysis to compare kinematic and kinetic differences between anterior and …

Adaptation Of Moiré Phase Tracking To A Mobile Device For Field 3d Data Collections, Amar Nikhanj

Theses and Dissertations

The accelerating technologies of mobiles devices such as tablets and phones provide an ability to

perform high intensity calculations all while obtaining precise data with increasingly more accurate

sensors. Image metrology and 3D motion tracking can take advantage of these improvements as

they require both significant processing power and camera controls not seen in mobile devices until

very recently. This thesis discusses the development of 3D motion tracking using Google Nexus

tablets and applying the technology to the Rapid Upper Limb Assessment (RULA) to demonstrate

the technology’s application to field measurements. RULA analysis determines the stress placed on

a human …

Evidence Of Ancient Maya Agriculture In The Bajos Surrounding Tikal, Guatemala, Adam Calvin Parker

Theses and Dissertations

Current Central American agricultural practices are environmentally and economically unsustainable, yet the ancient Maya who lived in the same region thrived for thousands of years. Archaeologists have attempted to understand the factors enabling the prolonged success and ultimate collapse of the Maya societies. Some have proposed that the karst seasonal wetlands, called bajos, that border many Maya sites in the region were an influential factor in the Maya's ability to flourish. For the past decade, researchers have used carbon isotope analyses to identify areas of ancient maize agriculture at Maya archaeological sites. In this study, we collected soil samples from …

Calcium Signaling And Ca2+/Calmodulin-Dependent Kinase Ii Activity In Epithelial To Mesenchymal Transition, Melissa Ann Mcneil

Theses and Dissertations

Epithelial to mesenchymal transition (EMT) is an important process in embryonic development, tissue repair, inflammation, and cancer. During EMT, epithelial cells disassemble cell-cell adhesions, lose apicobasal polarity, and initiate migratory and invasive processes that allow individual cells to colonize distant sites. It is the means by which non-invasive tumors progress into malignant, metastatic carcinomas. In vitro, EMT occurs in two steps. First, cells spread out, increasing in surface area and pushing the colony borders out. Then cells contract, pulling away from neighboring cells and rupturing cell-cell junctions, resulting in individual highly migratory cells. Recent discoveries indicate that calcium signaling is …

Maternal Denning Phenology And Substrate Selection Of Polar Bears (Ursus Maritimus) In The Southern Beaufort And Chukchi Seas, Jay Wesley Olson

Theses and Dissertations

Loss of sea ice due to global warming may affect the phenology and distribution of polar bear (Ursus maritimus) denning by altering access to denning habitats. We examined trends in the selection of maternal denning substrate (land versus sea-ice denning) in the southern Beaufort Sea (SB), addressing the potential influence of summer land-use and fall sea-ice conditions on substrate selection. We developed an algorithm based on statistical process control methods to remotely identify denning bears and estimate denning phenology from temperature sensor data collected on collars deployed 1985–2013 in the SB and Chukchi Sea (CS). We evaluated cub …

Time-Resolved, Near Atomic Resolution Structural Studies At The Free Electron Laser, Jason James Tenboer

Theses and Dissertations

Time-resolved serial femtosecond crystallography (TR-SFX) employs X-ray free electron lasers (XFELs) to provide X-ray pulses of femtosecond (fs) duration with 1012 photons per pulse. These XFELs are more than a billion times more brilliant than 3rd generation synchrotron X-ray sources. For structure determination, protein crystals on the micrometer length scale (microcrystals) are injected into the X-ray beam and the resulting diffraction patterns are recorded on fast-readout pixel detectors. Although these intense pulses deposit enough energy to ultimately destroy the protein, the processes that lead to diffraction occur before the crystal is destroyed. This so-called diffraction-before-destruction principle overcomes radiation damage, which …

Porphyrin As A Spectroscopic Probe Of Net Electric Fields In Heme Proteins, Hannah Elizabeth Wagie

Theses and Dissertations

Heme proteins have diverse functions as well as varied structures but share the same organic, conjugated cofactor. Similarly varied approaches have been taken to deduce how heme can take on different roles based on its protein environment. A unique approach is to view the protein matrix as a constellation of point charges that generates a defined, reproducible, net internal electric field that has influence over the electronic properties of the heme cofactor. This work considers how porphyrins, the basic chromophore building block of heme, can be used as a native spectroscopic sensor of internal electric field at the active site …

Neural Mechanisms Supporting Differential Auditory Fear Conditioning, Nicole Christine Ferrara

Theses and Dissertations

Pavlovian fear conditioning provides an ideal way to study memory formation, retention, and updating. Plasticity in the auditory thalamus is required during the acquisition and consolidation of a fear memory when a tone signals a foot shock. The medial geniculate nucleus (MgN) of the auditory thalamus sends projections to the amygdala and auditory cortex and is functionally divided into two different regions, the medial division (MGm) and the ventral division (MGv). Traditionally, these divisions are thought to relay auditory information to the amygdala during fear-related associative learning. However, recent research has suggested a more complex role for the MgN when …

The Development Of The Single-Leg Landing Error Scoring System (Sl-Less) For Lower Extremity Movement Screening, Maegan L. O'Connor

Theses and Dissertations

Introduction: Musculoskeletal knee injuries are some of the most common sports-related injuries. Movement screening assessments are often implemented to identify high-risk individuals in order to prevent the injury and the negative long-term consequences related to sustaining these injuries. While there are numerous established field-based assessments none have shown a strong ability to predict future injury. Additionally, there is currently there is no two-dimensional (2D) screening measure to evaluate the movement of multiple body segments in more than one plane during a single-leg task. The purpose of this study was to investigate the validity and reliability of the Single-Leg Landing Error …

Effects Of Global Dna Methylation Changes On Neurobehavior In Zebrafish, Matthew Christopher Pickens

Theses and Dissertations

A number of environmental neurotoxicants modulate DNA methylation, but its influence on neurobehavior remains unclear. The laboratory has established that low-level developmental methylmercury exposure induces neurobehavioral deficits; the current results demonstrate that it also induces global DNA hypomethylation. DNA methyltransferase 1-mutant zebrafish (exhibit ~70% reduction in enzymatic activity) were used to assess the role of DNA hypomethylation on behavior. Several neurobehavioral assays including the C-start escape, circadian rhythm, basic locomotion and visual-motor response (VMR) were also performed. There was a significant difference in VMR between the wild type and mutant animals. Other behavior assays revealed no significant difference, primarily due …

Effects Of Shrub Encroachment And Removal On South Texas Coastal Prairie Flora, Parker Alex Watson

Theses and Dissertations

Watson, Parker Alex, Effects of shrub encroachment and removal on South Texas coastal prairie flora. Master of Science, December, 2015. 60 pages, 14 tables, 11 figures, 47 references, 5 appendices. Native-invasive honey mesquite (Prosopis glandulosa) and huisache (Acacia farnesiana) are aggressively encroaching onto South Texas coastal prairies, outcompeting Gulf cordgrass (Spartina spartinae) and associated prairie vegetation with potential legacy effects on the landscape. To measure conditions in the presence of shrubs, data loggers were installed for 16 mos in shrub understories and grass cover to monitor light, soil and air temperatures. Vegetation and canopy surveys were also conducted to evaluate …

Validating Side Scan Sonar As A Fish Survey Tool, Michael A. Bollinger

Theses and Dissertations

Hydroacoustic methods can be used to answer a variety of questions regarding fish populations and behavior. In this study, side scan sonar methodology was developed to quantify abundance and biomass and compared to established visual observation methods on SCUBA over artificial reef structures in the western Gulf of Mexico. Side scan sonar methods were equivalent to SCUBA surveys for measuring fish abundance over the same reef areas, however, abundances were significantly higher when the larger area sampled by side scan was utilized. Side scan sonar methods were also more time efficient than SCUBA, ROV and long line fishing methods (66.7%, …

Comparing Reproductive Capacity Of Nearshore And Offshore Red Snapper, Lutjanus Campechanus, On Artificial Reefs In The Western Gulf Of Mexico, Ricky J. Alexander

Theses and Dissertations

Red snapper collected quarterly from four artificial reefs in south Texas were examined to compare total length, total weight, age, and the proportion of male to female red snapper, calculate gonadosomatic index values, batch fecundity, annual spawning frequency, and annual fecundity, and estimate size and age at maturity. Spawning occurred from April to September, with most active spawning observed in June (58%). Despite larger red snapper producing more eggs, and fish being larger offshore, most active spawning (68%) and egg production (74%) was observed nearshore. Female red snapper reached 50% maturity (L50) between 350-550 mm, and L75 by 600 mm. …

Decomposition And Nitrogen Dynamics Of Turtle Grass (Thalassia Testudinum) In A Subtropical Estuarine System, Monica Delgado

Theses and Dissertations

Seagrass beds are pivotal in the functioning of coastal ecosystems in terms of productivity, organic matter turnover and nutrient cycling. Aiming to document decay and nitrogen (N) dynamics of turtle grass (Thalassia testudinum) in a subtropical estuarine system, decomposition patterns of leaves and rhizomes were characterized and compared. Nitrogen usage during decomposition of tissues, and of live tissues and epiphytes growing on live leaves, was also quantified and compared. Stable isotope ratios allowed tracing N within the seagrass bed, following N incorporation into seagrass tissues from the surrounding media (water, sediment). Leaves had a higher N content and decomposed at …

Examination Of The Chagas Disease Vector, Triatoma Gerstackeri, In The Lower Rio Grande Valley, Alfredo Flores

Theses and Dissertations

Chagas disease is caused by the protozoan parasite Trypanosoma cruzi, which is carried by an insect vector of the family Reduviidae, and of the subfamily Triatomina. The species Triatoma gerstaeckeri is identified as the primary vector of T. cruzi within the Rio Grande Valley. Species of Triatoma gerstaeckeri were trapped in La Sal del Rey National Refuge in 2012 and 2013.

Data indicates a seasonal dispersal pattern of activity for T. gerstaeckeri. Optimal time of capture was between 1-2 hours after sunset. Different methods were utilized to determine the best combination of lures. Results indicate that the UV-light alone is …