Life Sciences Commons^™

Structure And Function Of Proteins Investigated By Crystallographic And Spectroscopic Time-Resolved Methods, Namrta Purwar

Theses and Dissertations

Biomolecules play an essential role in performing the necessary functions for life. The goal of this thesis is to contribute to an understanding of how biological systems work on the molecular level. We used two biological systems, beef liver catalase (BLC) and photoactive yellow protein (PYP). BLC is a metalloprotein that protects living cells from the harmful effects of reactive oxygen species by converting H2O2 into water and oxygen. By binding nitric oxide (NO) to the catalase, a complex was generated that mimics the Cat-H2O2 adduct, a crucial intermediate in the reaction promoted by the catalase. The Cat-NO complex is …

Transcending Microbial Source Tracking Techniques Across Geographic Borders: An Examination Of Human And Animal Microbiomes And The Integration Of Molecular Approaches In Pathogen Surveillance In Brazil And The United States, Amber Mae Koskey

Theses and Dissertations

Waterborne illnesses, attributed to the ingestion or contact with contaminated water, present a significant global health concern. Surface water sources can be impacted by wide array of pollution inputs, but fecal pollution generates the most significant and acute threat to human health. Therefore, the detection of fecal bacteria in surface water sources remains an important public health objective. Current surface water monitoring employs the use of fecal indicator bacteria (FIB) including E. coli and enterococci as proxies for pathogenic organisms carried in fecal pollution. These traditional indicators, detected by culture-based microbiological methods, do not discriminate fecal sources from another. New …

Neural Responses During Trace Conditioning With Face And Non-Face Stimuli Recorded With Magnetoencephalography, Nicholas Lee Balderston

Theses and Dissertations

During fear conditioning a subject is presented with an initially innocuous stimulus like an image (conditioned stimulus; CS) that predicts an aversive outcome like a mild electric shock (unconditioned stimulus; UCS). Subjects rapidly learn that the CS predicts the UCS, and show autonomic fear responses (CRs) during the presentation of the CS. When the CS and the UCS coterminate, as is the case for delay conditioning, individuals can acquire CRs even if they are unable to predict the occurrence of the UCS. However when there is a temporal gap between the CS and the UCS, CR expression is typically dependent …

Lake Michigan Hydrodynamics: Mysis And Larval Fish Interactions, Yutta Wang

Theses and Dissertations

I studied the interactions between Lake Michigan hydrodynamics (the spring thermal bar) and Mysis, deepwater sculpin, and burbot larvae. The thermal bar is a zone of sinking 4º С water that separates warmer inshore water from colder offshore water. Mysis was a major bycatch of sampling for larval fishes. The density of Mysis did not differ statistically between inshore (about 6º С) and offshore of the thermal bar, but the percentage of Mysis that were newborns was significantly higher inshore (P = 0.007). These "early start" coastal Mysis may have an advantage in growth and survival, but with the risk …

The Role Of The Amygdala, Retrosplenial Cortex, And Medial Prefrontal Cortex In Trace Fear Extinction And Reconsolidation, Janine Lynn Kwapis

Theses and Dissertations

A wealth of research has outlined the neural circuits responsible for the consolidation, reconsolidation, and extinction of standard "delay" fear conditioning, in which awareness is not required for learning. Far less is understood about the neural circuit supporting more complex, explicit associations. "Trace" fear conditioning is considered to be a rodent model of explicit fear because it relies on the cortex and hippocampus and requires explicit contingency awareness in humans for successful acquisition. In the current set of studies, we aimed to better characterize the neural circuit supporting the consolidation, reconsolidation, and extinction of trace fear in order to better …

Evaluation Of Vdr-Coactivator Inhibitors Using Biochemical And Cell-Based Assays, Athena Marie Baranowski

Theses and Dissertations

ABSTRACT

EVALUATION OF VDR–COACTIVATOR INHIBITORS USING BIOCHEMICAL AND CELL–BASED ASSAYS

by

Athena Baranowski

The University of Wisconsin–Milwaukee, 2013

Under the Supervision of Dr. Alexander Arnold

The vitamin D receptor (VDR) is a ligand–dependent transcription factor, which belongs to the nuclear receptor superfamily. VDR–mediated gene regulation is governed by coregulators (coactivators and corepressors). VDR coregulator binding inhibitors (CBIs), which were discovered using high throughput screening (HTS), were evaluated using cell–based assays and biochemical assays to determine their ability to inhibit the interaction between VDR and steroid receptor coactivator–2 (SRC–2). Determining their ability to inhibit the VDR–SRC–2 interaction can lead to the …

Arabidopsis Serk1 And 2 Regulate Anther Development As Co-Receptors Of Ems1, Yao Wang

Theses and Dissertations

In flowering plants, male reproductive cell differentiation, one of the most critical events in the early stage of sexual reproduction, occurs during anther development. In the model plant species Arabidopsis, anther development in each lobe results in the differentiation of five highly organized cell layers with unique identities, including the central male reproductive cells and four somatic cell layers. These features make the Arabidopsis anther an ideal system in which to investigate the mechanisms of cell fate determination and differentiation. Previous studies have demonstrated that a leucine-rich repeat receptor-like kinase (LRR-RLK), EXCESS MICROSPOROCYTES1 (EMS1/EXS1), plays an important role during Arabidopsis …

Influence Of Genetic Variation In The Biotic Environment On Phenotypic Variation In A Plant-Feeding Insect, Darren Rebar

Theses and Dissertations

While many species spend much of their lives in close association with other organisms, only recently have biologists started to explore the implications of the biotic nature of environments for their role as causes of variation in phenotypes. This means that the genotypes of individuals that constitute the biotic environment may influence the phenotypes of individuals that live in that environment. These are called indirect genetic effects (IGEs) when they occur between conspecifics, and interspecific indirect genetic effects (IIGEs) when they occur between heterospecifics. However, the impact of genetic variation in biotic environments remains largely unknown. I used a member …

Evaluating The Influence Of Environmental Factors On The Rate Of Extra-Pair Matings In Tropical And Temperate Populations Of The House Wren (Troglodytes Aedon), Kaitlin Claire Mckenney

Theses and Dissertations

Considerable variation exists in the rate of extra-pair matings (EPMs) in birds. Environmental variability likely influences EPM rates within species, but the effects of local environmental factors on EPM rates are largely unpredictable. To determine whether broad-scale environmental factors might be better predictors of EPM rates within species, we quantified levels of extra-pair paternity in the house wren (Troglodytes aedon) in four populations spanning a range of latitude, elevation, and primary productivity (measured by actual evapotranspiration rates). Our results indicated an intermediate and variable level of EPM among populations (6 -31% extra-pair young) that was not significantly affected by 3 …

The Role Of Gap-43 Phosphorylation In Axon Behavior In The Developing Zebrafish Visual System, Jennifer Forecki

Theses and Dissertations

Developing neurons extend processes to specific targets and establish connections that are essential for future function of the nervous system. One of these processes, the axon, has a motile tip called a growth cone that rearranges its membrane-associated actin cytoskeleton to turn toward or away from environmental guidance cues. Growth associated protein 43 (GAP-43) is one of the most abundant proteins associated with axonal growth cone membranes and is known to modulate the formation and stability of the actin cytoskeleton during axon guidance. Protein kinase C (PKC)-mediated phosphorylation of GAP-43 on serine 42 regulates its interactions with actin. Phosphorylated GAP-43 …

A Synthetic Biology Approach To Engineering New Anticancer Agents, Shane Robert Wesener

Theses and Dissertations

Histone deacetylase (HDAC) inhibitors are becoming increasingly valuable therapeutic agents in treatment of several types of malignancies. FK228 is a depsipeptde anticancer compound produced by Chromobacterium violaceum no. 968 through a nonribosomal peptide synthetase (NRPS)-polyketide synthase (PKS) hybrid assembly line. In the present study, reconstitution of the biosynthetic pathway responsible for the production of FK228 revealed cross-talk between modular PKS and fatty acid synthase. This pathway contains two PKS modules on the DepBC enzymes that lack a functional acyltransferase (AT) domain, and no apparent AT-encoding gene exists within the gene cluster or its vicinity. We reported through heterologous expression of …

Phylogeographic Inference Of Insular Mule Deer (Odocoileus Hemionus) Divergence In North America's Desert Southwest, Ona Alminas

Theses and Dissertations

Though mule deer (Odocoileus hemionus) persist in robust populations throughout most of their North American distribution, nearly 60% of their historic range in México has declined due to habitat loss and unregulated hunting. Two of the six subspecies inhabiting México's deserts and Baja California peninsula are of conservation concern, occurring on land bridge islands in the Pacific Ocean (O. h. cerrosensis on Cedros Island: threatened) and in the Sea of Cortés (O. h. sheldoni on Tiburón Island: endangered). Focusing on the desert southwest (n=449 deer), we obtained 1,611 bp of mtDNA sequence (control region: 583 bp; cytochrome b gene: 1,028 …

Protein Association In Living Cells Using Fret Spectrometry: Application To G-Protein Coupled Receptors, Suparna Patowary

Theses and Dissertations

Recent advancements in fluorescence microscopy coupled with newly developed fluorescent tags have transformed Fluorescence (Förster) Resonance Energy Transfer (FRET) into a powerful tool studying in vivo molecular interactions with improved spatial (angstrom) resolution. Though widely used to study protein-protein interactions, generalizing and testing the FRET theory for oligomeric complexes containing multiple donors and acceptors has only become possible in recent years. Therefore, many aspects of it are yet unexplored.

In this work, we tested the kinetic theory of FRET using linked fluorescent proteins located in the cytoplasm or at the plasma membrane. We used a novel method developed in our …

Life After Adhesion: L-Selectin Throughout The T Cell Lifespan, Abner Garcia Fernandez

Theses and Dissertations

Lymphocytes require antigenic encounter to activate and proliferate, eventually clearing the source of antigenic challenge. The peripheral lymph nodes (PLN) are the primary sites of antigenic encounter and thus the ability of lymphocytes to migrate to this tissue is a requirement for mounting effective immune responses. The process of lymphocyte migration to the PLN is known as the "adhesion cascade". Specifically, lymphocytes are captured from the blood through the adhesion molecule, L-selectin, followed by CC chemokine receptor 7 (CCR7)-mediated integrin activation, which ultimately results in cell transmigration into the PLN. Because the PLN is the site where antigenic encounter is …

Mathematical Modeling Of Physiological Characteristics In Female Soccer Athletes, Thomas S. Goeppinger

Theses and Dissertations

Intermittent sports create challenges regarding performance measurement. Quantification of various physiological characteristics can lead to increased performance and injury reduction throughout a season of competition. Currently, a variation of an athletes' heart rate is the primary physiological characteristic used for quantifying load on the athlete. With increasing technology, we have the ability to gather additional characteristics regarding the physicality of athletes during competition. This study statistically compares various models using these new characteristics as predictors to the athletes' lactate concentration in their blood. From this comparison, we determine which physiological characteristic(s) best represent the performance and fatigue of these athletes. …

Examining Mediators To Physical Activity As A Link To Interventional Efforts Aimed At Increasing Activity Levels And Improving Physical Functioning In Older Adults, Christopher Dondzila

Theses and Dissertations

The number of older adults living in the United States is growing at an increasingly rapid rate, and is host to a high prevalence of chronic diseases and physical impairments. Physical activity and exercise have been shown to be beneficial in impacting such conditions, yet the majority of older adults remain inactive. The purpose of this dissertation was to employ a sequence of studies to investigate mediators to physical activity, leading to an intervention to increase activity and promote health.

The purpose of Project VOICE was to examine whether awareness and utilization of community resources to promote physical activity and …

The Effects Of Static Stretching Versus Dynamic Stretching On Lower Extremity Joint Range Of Motion, Static Balance, And Dynamic Balance, Wenqing Wang

Theses and Dissertations

The purpose of this study was to examine the effects of static stretching (SS) versus dynamic stretching (SS) on lower extremity joint range of motion (ROM), static balance, and dynamic balance. Fifteen active subjects with tight hamstring and calf muscles participated. Hip flexion and knee extension ROM angle was measured using a fluid inclinometer. A closed-chain method of measuring ankle dorsiflexion ROM was used. Static balance was assessed in single-leg stance on a force plate using the time-to-boundary (TTB) measurement. The Star Excursion Balance Test (SEBT) was used to assess dynamic balance in three directions. These measurements were assessed before …

Habitat Matters For Inorganic Carbon Acquisition In 38 Species Of Red Macroalgae (Rhodophyta) From Puget Sound, Washington, Usa, Maurizio Murru

Theses and Dissertations

The ability of macroalgae to photosynthetically raise the pH and deplete the inorganic carbon pool from the surrounding medium has been in the past correlated with habitat and growth conditions. The objectives of this study were 1) to test for differences among a variety of red algal species in their ability to deplete the dissolved inorganic carbon pool (DIC) from the surrounding medium, and to utilize the HCO₃- fraction of the DIC, 2) to determine whether these differences were associated with red algal habitat defined as intertidal height and subtidal depth, and/or with taxonomic affinities of the species …

Exercise-Induced Hypoxia, Angiogenesis, And Behavioral Flexibility In The Adult Rat, Kiersten Lee Berggren

Theses and Dissertations

Exercise induces a myriad of effects on the brain from the growth of new capillaries and neurons, to improvements in cognitive performance. Additionally, recent research has shown that commencement of an exercise regimen also causes apoptosis. Therefore, it is possible that exercise-induced increases in oxygen demand cause the brain to transiently experience a state of hypoxia. To investigate this hypothesis, we measured protein levels of hypoxia inducible factor 1 alpha (HIF-1α), a transcription factor known to be upregulated in conditions of hypoxia or ischemia, in animals exposed to a single bout of treadmill exercise. After exercise animals were sacrificed at …

Metformin-Induced Pedf Expression Regulates Cell Proliferation And Lipid Metabolism In Prostate Cancer Cells, Miguel Angel Tolentino

Theses and Dissertations

Prostate cancer (PCa) is one of the most common cancers in American males. A high fat diet and obesity accelerate PCa progression and increase the 1risk of death from disease. Epidemiological studies have indicated that PCa patients with type 2 diabetes have higher mortality rates than PCa patients without diabetes. Type 2 diabetics who are on metformin, a drug to control blood sugar levels, show a delay in PCa progression in comparison with PCa patients with type 2 diabetes who are not on metformin. It has been proposed that metformin inhibits proliferation via activation of AMP-activated protein kinase (AMPK) or …

Zinc Chemical Biology: The Pursuit Of The Intracellular Targets Of Zinquin, Andrew Nowakowski

Theses and Dissertations

Fluorescent sensors have been a main microscopic tools used to understand Zn2+ physiology on a cellular level. The use of the fluorescent Zn2+ sensor Zinquin (ZQ) and its analogues have revealed that transient Zn2+ is a chief component in a variety of biochemical pathways. Yet, little work has been performed to validate the exact targets of Zinquin in a cellular environment. The goals of this investigation are to determine the types of Zinquin reactions that take place in the cell as well as the identities of its cellular targets.

It has been hypothesized that Zinquin reacts with free Zn2+ within …

Phytoplankton Life History Events: Resting Stages And Physiological Cell Death, Christine R. Kozik

Theses and Dissertations

Understanding and predicting changes in phytoplankton populations requires knowledge of key life history processes such as recruitment from benthic resting stages and losses due to sedimentation and cell death. Currently, these processes are poorly understood in freshwater systems. Phytoplankton resting stage and cell death life history events were separately examined in two freshwater systems in Wisconsin, four northern lakes and an urban pond. In the norther lakes, sedimentation and benthic recruitment were examined using sediment and recruitment traps that were sampled weekly over two summers. Sedimentation and benthic recruitment contributed little to changes in standing crop chl a, but rather …

The Relationship Between The Functional Movement Screen™ And Countermovement Jump Height, Joshua Keegan Conlon

Theses and Dissertations

Introduction: Pre-participation measures of functional movement and functional performance are commonly used to gauge injury risk and performance baselines before engaging in activity. Functional movement can be evaluated using the Functional Movement ScreenTM (FMSTM). Performance on the FMSTM has been shown to be related to injury risk by previous researchers. Functional performance can be evaluated with countermovement jump (CMJ) testing; performance on a CMJ demonstrates transferable power to athletic tasks. Performance literature has shown that there are movement factors that influence CMJ height. However, to date a significant relationship between performance on functional movement and functional performance tests has not …

The Role Of A Camkii/Pka-Protein Degradation-Glur2 Pathway In The Control Of Memory Updating Following Retrieval, Timothy Jarome

Theses and Dissertations

Reconsolidation is thought to be a process whereby consolidated memories can be modified following retrieval. However, very little is known about the molecular mechanisms that regulate this reconsolidation process. In the present series of experiments we tested if memories "destabilize" or become labile following retrieval through a specific signaling pathway. We found that retrieval of a contextual fear memory differentially increased proteasome activity in the amygdala and hippocampus and resulted in unique changes in AMPA receptor subunit expression in these brain regions. These changes were dependent on CaMKII activity, which was required for increases in Rpt6-S120 phosphorylation, proteasome activity and …

Dissociation Of Β1 And Β2 Adrenergic Receptor Subtypes In Retrieval And Reconsolidation Of A Cocaine Conditioned Place Preference, Michael Fitzgerald

Theses and Dissertations

Drug-seeking behavior is maintained by encounters with drug-associated cues, and disrupting retrieval or reconsolidation of the drug-cue associations could reduce the risk of relapse. Previous work has shown beta-adrenergic receptor (beta-AR) antagonists can prevent retrieval or reconsolidation of a cocaine conditioned place preference (CPP) when administered either before or after test, respectively (Otis and Mueller, 2011; Otis et al., 2013). However, the specific beta-AR subtypes that mediate retrieval and reconsolidation of a cocaine CPP remain unknown. Here we used selective blockade of & beta-1 or beta-2-AR subtypes to determine the effects on retrieval and reconsolidation of a cocaine CPP. During …

Cellular Metabolism And Its Effect On The Type Iii Secretion System Of Dickeya Dadantii 3937, William Cortrell Hutchins

Theses and Dissertations

Nutrition, in both eukaryotes and prokaryotes, is vital to the life and well-being of the species. In organisms such as Escherichia coli, metabolism and its regulation have been well established, whereas in Dickeya dadantii 3937, the metabolic pathways and their effects on other processes have not been elucidated. Little is known is how carbon metabolism is able to regulate virulence and pathogenicity in this organism. In this work, we have investigated how the metabolic network contributes to positively and negatively regulating the pathogenicity of Dickeya dadantii 3937.

Chapter 1 provides an overview of the history and virulence processes in …

Effect Of Remote Vibrotactile Noise On Pinch Force Maintenance Ability And Brain Activity, Ying-Ling Tseng

Theses and Dissertations

Noise has been used to enhance detection of signals thereby improving performance of nonlinear systems (referred to as "stochastic resonance"). In biological systems, the noise and signal integration may occur not only at the receptor level but also in the central nervous system, thereby allowing noise remotely applied from a signal to enhance the system's response to the signal. However, integration of tactile signal and noise within the central nervous system has not been demonstrated in humans. In addition, whether the enhanced detection of tactile signals with remote noise results in changes in motor behavior is unknown.

The objectives of …

Seasonality Of Conceptions Under Varying Conditions In A Rhesus Macaque Breeding Colony, Ryan Disney Patrick Dunk

Theses and Dissertations

Rhesus macaques (Macaca mulatta) are well documented as seasonal breeders. Despite this, little is known about what factors influence seasonal reproduction in rhesus. It has been proposed that rhesus are "relaxed income breeders" (Brockman and van Schaik, 2005), which means they respond to changes in photoperiod but endogenous cues can allow deviations from photoperiod-timed seasonality. This study presents the results of a natural experiment on the influence of different housing conditions (featuring different levels of environmental exposure) on the seasonal pattern of reproduction in rhesus. Once the number of attempts was controlled for, rhesus did not exhibit a seasonal distribution …

An Examination Of The Psychological Skills Profiles Of Oval Racers And Road Racers, Andrew Morgan

Theses and Dissertations

Introduction: Given the global popularity and far-reaching economics of auto racing, it is surprising how few studies have examined the sport generally and the psychological aspects of the sport specifically. Consistent with this general lack of research is the specific absence of studies examining the psychological skills needed to participate in the two main disciplines of auto racing, specifically oval and road racing. The purpose of the current study was to examine the use of psychological skills by athletes who participate in distinct sub-disciplines within the sport of auto racing, specifically oval racers and road racers. Methods: A total of …

Alcohol Biomarkers As Predictive Factors Of Rearrest In High Risk Repeat Offense Drunk Drivers, Brian Charles Kay

Theses and Dissertations

Alcohol biomarkers, or naturally occurring molecules which occur in response to one's alcohol consumption, are proving to be a value tool in objectively monitoring one's alcohol consumption. Coupling this assessment tool, with advances in computing power, new and powerful predictions are becoming evermore possible. In this retrospective study, data was first collected that consisted of a sample of 249 drivers convicted of driving under the influence charge and who monitored over the course of a year by biomarker blood tests. This data was then analyzed using machine learning methods. TwoStep cluster analysis showed distinct drinking groups within the drivers who …