Life Sciences Commons^™

Molecular Mechanisms Regulating Chemokine Receptor Cxcr4 Signaling And Trafficking, Rohit Malik

Dissertations

CXCR4 is a G protein-coupled receptor (GPCR) that binds to the chemokine, stromal cell-derived factor-1 (SDF-1alpha; a.k.a. CXCL12). The SDF-1alpha/CXCR4 signaling axis plays an essential role during embryogenesis in the development of the heart, brain and vasculature and in the adult mediating immune cell trafficking and stem cell homing to the bone marrow. Dysregulation of SDF-1alpha/CXCR4 signaling is linked to several pathological conditions, including cardiovascular disease, immunological disorders as well as cancer growth and metastasis. However, the mechanisms that govern CXCR4 signaling remain poorly understood. In this dissertation project, we attempt to further our understanding of the molecular mechanisms that …

An Investigation Of The Phospholamban-Serca Regulatory Interaction With Fluorescence Resonance Energy Transfer, Philip Adam Bidwell

Dissertations

With Fluorescence Resonance Energy Transfer (FRET), we are able to detect changes in the structure and affinity of the PLB-SERCA regulatory complex in live cells. Using this approach, we have detected a high level of PLB-SERCA interaction even at Ca2+ concentrations known to fully relieve PLB inhibition of SERCA, suggesting that dissociation is not required for relief of inhibition. We also detect no real-time change in PLB-SERCA binding over the course of a single Ca2+ transient in paced myocytes. The effect of Ca2+ on the PLB-SERCA interaction is best described as a reduced affinity with no change in the structure …

Receptor-Mediated Hypertrophic Signaling Via Protein Kinase D And Histone Deacetylase 5 In Adult Myocytes, Chia-Wei Jenny Chang

Dissertations

Hemodynamic stress and neurohumoral signaling are common causes of cardiac hypertrophy. These extrinsic stress stimuli typically act on GPCR and induce a cascade of signal transduction to re-program terminally differentiated myocytes to grow in length or width. The compensatory hypertrophic response can enhance cardiac output briefly due to increased work load. However, prolonged stress results in maladaptive changes in the heart and gradually deteriorates ventricular function to supply blood throughout the body. Sustained hypertrophic signaling can also progress toward heart failure.

My dissertation research focuses on the hypertrophic signaling in adult cardiac myocytes in response to neurohumoral stimuli, ET-1 and …

Effects Of Binge Alcohol Exposure On Canonical Wnt Signaling During Fracture Repair, Kristen Leigh Lauing

Dissertations

Excessive alcohol consumption is associated with increased fracture risk, delayed bone healing and fracture non-union. Binge alcohol consumption has occurred in 25-40% of all orthopaedic trauma cases. The canonical Wnt pathway, through tight regulation of stabilized beta-catenin, plays an essential and pivotal role in the formation of new bone and cartilage to initiate bone repair. We sought to determine the molecular mechanisms behind alcohol-related fracture complications by testing the hypothesis that binge alcohol exposure deregulates canonical Wnt signaling in the fracture callus, leading to impaired healing.

To test this, C57BL/6 or beta-catenin/TCF-reporter male mice were exposed to intraperitoneal alcohol or …

The Role Of Cyp33 In Mll Mediated Gene Repression, Steven D. Poppen

Dissertations

Mixed Lineage Leukemia (MLL) is a multidomain protein whose gene is translocated in a subset of AML leukemias. Translocation of the MLL gene is present in approximately five percent of adult acute leukemias and ten percent of pediatric leukemias (Daser, A 2004, Look, A 1997, Huret, J 2001) Patients presenting in the clinic at the time of diagnosis with an MLL fusion have been shown to respond poorly to treatment and have a worse prognosis than matched wild type MLL patients (Rubnitz, J 1994, Rubnitz, J 1999). Novel therapies therefore are needed in order to more effectively treat patients with …

Compositional Determinants Of The Pharmacological Actions Of Heparins, Angel Lee Gray-Shah

Dissertations

This dissertation primarily focuses on how differences in molecular weight (MW) and structural composition affect the pharmacological activity of heparin and its derivatives. Heparins are a mixture of glycosaminoglycans chains which are used to prevent thrombosis in a number of clinical indications. Heparins promote the inhibition of blood coagulation via their plasmatic cofactors antithrombin (AT) and heparin cofactor II (HCII).

In these studies, various heparins with molecular weights ranging from 2.6 to 16.5 kDa were investigated. Not only the molecular weight but also the oligosaccharide composition greatly varied in these agents. One of the major objectives of this research was …

Inefficient Replication Reduces Reca-Mediated Repair Of Uvdamaged Plasmids Introduced Into Competent Escherichia Coli, Harout Arthur Jeiranian, Charmain T. Courcelle, Justin Courcelle

Biology Faculty Publications and Presentations

Transformation of Escherichia coli with purified plasmids containing DNA damage is frequently used as a tool to characterize repair pathways that operate on chromosomes. In this study, we used an assay that allowed us to quantify plasmid survival and to compare how efficiently various repair pathways operate on plasmid DNA introduced into cells relative to their efficiency on chromosomal DNA. We observed distinct differences between the mechanisms operating on the transforming plasmid DNA and the chromosome. An average of one UV-induced lesion was sufficient to inactivate ColE1-based plasmids introduced into nucleotide excision repair mutants, suggesting an essential role for repair …

Uvrd Participation In Nucleotide Excision Repair Is Required For The Recovery Of Dna Synthesis Following Uv-Induced Damage In Escherichia Coli, Kelley Nicole Newton, Charmain T. Courcelle, Justin Courcelle

Biology Faculty Publications and Presentations

UvrD is a DNA helicase that participates in nucleotide excision repair and several replication-associated processes, including methyl-directed mismatch repair and recombination. UvrD is capable of displacing oligonucleotides from synthetic forked DNA structures in vitro and is essential for viability in the absence of Rep, a helicase associated with processing replication forks. These observations have led others to propose that UvrD may promote fork regression and facilitate resetting of the replication fork following arrest. However, the molecular activity of UvrD at replication forks in vivo has not been directly examined. In this study, we characterized the role UvrD has in processing …

Cgi-58/Abhd5-Derived Signaling Lipids Regulate Systemic Inflammation And Insulin Action, Caleb C. Lord, Jenna L. Betters, Pavlina T. Ivanova, Stephen B. Milne, David S. Myers, Jennifer Madenspacher, Gwynneth Thomas, Soonkyu Chung, Mingxia Liu, Matthew A. Davis, Richard G. Lee, Rosanne M. Crooke, Mark J. Graham, John S. Parks, Dawn L. Brasaemle, Michael B. Fessler, H. Alex Brown, J. Mark Brown

Department of Nutrition and Health Sciences: Faculty Publications

Mutations of comparative gene identification 58 (CGI-58) in humans cause Chanarin-Dorfman syndrome, a rare autosomal recessive disease in which excess triacylglycerol (TAG) accumulates in multiple tissues. CGI-58 recently has been ascribed two distinct biochemical activities, including coactivation of adipose triglyceride lipase and acylation of lysophosphatidic acid (LPA). It is noteworthy that both the substrate (LPA) and the product (phosphatidic acid) of the LPA acyltransferase reaction are wellknown signaling lipids. Therefore, we hypothesized that CGI-58 is involved in generating lipid mediators that regulate TAG metabolism and insulin sensitivity. Here, we show that CGI-58 is required for the generation of signaling lipids …

Muscadine Grape (Vitis Rotundifolia) And Wine Phytochemicals Prevented Obesity-Associated Metabolic Complications In C57bl/6j Mice, Vishnupriya Gourineni, Neil F. Shay, Soonkyu Chung, Amandeep K. Sandhu, Liwei Gu

Department of Nutrition and Health Sciences: Faculty Publications

The objective of this study was to determine the effects of muscadine grape or wine (cv. Noble) phytochemicals on obesity and associated metabolic complications. Muscadine grape or wine phytochemicals were extracted using Amberlite FPX66 resin. Male C57BL/6J mice were given a low-fat diet (LF, 10% kcal fat), high-fat diet (HF, 60% kcal fat), HF + 0.4% muscadine grape phytochemicals (HF+MGP), or HF + 0.4% muscadine wine phytochemicals (HF+MWP) for 15 weeks. At 7 weeks, mice fed HF+MGP had significantly decreased body weights by 12% compared to HF controls. Dietary MGP or MWP supplementation reduced plasma content of free fatty acids, …

Successful Aging: A Psychosocial Resources Model For Very Old Adults, G. Kevin Randall, Peter Martin, Mary Ann Johnson, Leonard W. Poon

Department of Nutrition and Health Sciences: Faculty Publications

Objectives.Using data from the first two phases of the Georgia Centenarian Study, we proposed a latent factor structure for the Duke OARS domains: Economic Resources, Mental Health, Activities of Daily Living, Physical Health, and Social Resources. Methods. Exploratory and confirmatory factor analyses were conducted on two waves of the Georgia Centenarian Study to test a latent variable measurement model of the five resources; nested model testing was employed to assess the final measurement model for equivalency of factor structure over time. Results. The specified measurement model fit the data well at Time 1. However, at Time 2, …

Choreographing The Adenylyl Cyclase Signalosome: Sorting Out The Partners And The Steps, Rennolds S. Ostrom, Amy S. Bogard, Robert Gros

Pharmacy Faculty Articles and Research

Adenylyl cyclases are a ubiquitous family of enzymes and are critical regulators of metabolic and cardiovascular function. Multiple isoforms of the enzyme are expressed in a range of tissues. However, for many processes, the adenylyl cyclase isoforms have been thought of as essentially interchangeable, with their impact more dependent on their common actions to increase intracellular cyclic adenosine monophosphate content regardless of the isoform involved. It has long been appreciated that each subfamily of isoforms demonstrate a specific pattern of “upstream” regulation, i.e., specific patterns of ion dependence (e.g., calcium-dependence) and specific patterns of regulation by kinases (protein kinase A …

Vorinostat: A Potent Agent To Prevent And Treat Laser-Induced Corneal Haze, Ashish Tandon, Jonathan C. K. Tovey, Michael R. Waggoner, Ajay Sharma, John W. Cowden, Daniel J. Gibson, Yuanjing Liu, Gregory S. Schultz, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

PURPOSE—This study investigated the efficacy and safety of vorinostat, a deacetylase (HDAC) inhibitor, in the treatment of laser-induced corneal haze following photorefractive keratectomy (PRK) in rabbits in vivo and transforming growth factor beta 1 (TGFβ1) -induced corneal fibrosis in vitro.

METHODS—Corneal haze in rabbits was produced with −9.00 diopters (D) PRK. Fibrosis in cultured human and rabbit corneal fibroblasts was activated with TGFβ1. Vorinostat (25 μm) was topically applied once for 5 minutes on rabbit cornea immediately after PRK for in vivo studies. Vorinostat (0 to 25 μm) was given to human/rabbit corneal fibroblasts for 5 minutes or 48 …

In Vivo Evaluation Of Microfibrous Bioactive Borate Glasses For Use In Wound Healing, Yinan Lin

Masters Theses

"This project consisted of two parts focused on in vivo evaluation of microfibrous bioactive borate glasses for use in wound healing. Part one of the project involved subcutaneous implantation of two types of borate glass microfibers and 45S5 glass micro fibers in the dorsum of rats and histologically evaluating the soft tissues at the implant sites at 2 to 4 weeks post surgery. The primary objective was to assess the angiogenic response to the implanted materials. The 13-93B3 and 13-93B3Cu glass microfibers were found to significantly increase the microvascular density in soft tissue, an outcome that suggests these simple and …

Physiochemical Characteristics Contributing To The Cytotoxicity Of Transition Metal Oxides, Chi-Heng Wu

Masters Theses

"In the past ten years nanotechnology has not only evolved to play a prominent role in our economy but also increased the concern over potential adverse effects caused by nanomaterials to human health and the environment. Nanotoxicity is to understand the nature and origin of the toxicity imposed by nanomaterials. Studies from our laboratory have shown that nanoparticle induces oxidative stress, perturbs calcium homeostasis, alter gene expression, and produces pro-inflammatory responses. We also identified a trend of toxicity: TiO₂ < Cr₂O₃ < Fe₂O₃ < Mn₂O₃ < NiO < ZnO < CuO. We then asked a question: what are physiochemical factors of transition metal nanoparticles that contributed to this increasing cytotoxicity. In this thesis I investigated the correlation between physicochemical properties and toxicity of the transition metal oxides in the 4th Period of the Periodic Table of Elements. Particle size, BET surface area, point of zero charge, metal dissolution, and degree of surface adsorption of transition metal oxide nanoparticles were measured. There were no increasing trends in both particle size and specific surface area. The point of zero charge showed an increasing trend as TiO₂ < Cr₂O₃ < Fe₂O₃ < NiO < CuO = ZnO < Mn₂O₃. The number of available binding sites of nanoparticle showed an increasing trend as Cr₂O₃ > ZnO > CuO > NiO > Fe₂O₃ > Mn₂O₃ > TiO₂. The degree of adsorption on the surface of nanoparticles showed an increasing trend with atomic …

Development Of Capillary Electrophoresis For The Analysis Of Phenolics And Glucoraphanin In Brassica Oleracea, Iris Lee

Theses: Doctorates and Masters

Capillary electrophoresis (CE) has been used increasingly more over the last decade in the area of food analysis. Numerous food products and food components have been analysed using this technique because of its high efficiency and short separation times. However, the inherent lack of detection sensitivity in CE combined with the complex matrices present in many food samples, especially those of plant origins, is one of the contributing factors to the limited development on CE in this particular area of food analysis. In this project, the potential of CE as a tool in the analysis of vegetables belonging to the …

The Impact Of Black Swan (Cygnus Atratus) Grazing On The Seagrass Halophila Ovalis In The Lower Swan River Estuary, Gary Choney

Theses: Doctorates and Masters

Grazing is an important ecosystem process, influencing community structure and rates of ecosystem processes. Although grazing on seagrasses is generally considered to be minor in many temperate regions of the world, waterfowl are often considered significant grazers in temperate lagoons and estuaries. This study examined spatial and temporal variation in swan abundance, grazing pressure and the impact grazing has on seagrass. Little is known on how grazing rates vary on larger water bodies in the southern hemisphere at different times of year and whether temporal changes in grazing rates affect the ability of seagrasses to tolerate grazing. The plant response …

Lno Data Access Cedar Creek Site, Long Term Ecological Research Network

Long Term Ecological Research Network

This memorandum asks for feedback on a data availability policy to be used by PI of grants for LTER.

Coping Behaviour As An Adaptation To Stress: Post-Disturbance Preening In Colonial Seabirds, Shandelle M. Henson, Lynelle M. Weldon, James L. Hayward, Daniel Greene, Libby C. Megna, Maureen C. Serem

Faculty Publications

In humans, coping behaviour is an action taken to soothe oneself during or after a stressful or threatening situation. Some human behaviours with physiological functions also serve as coping behaviours, for example, comfort sucking in infants and comfort eating in adults. In birds, the behaviour of preening, which has important physiological functions, has been postulated to soothe individuals after stressful situations. We combine two existing modelling approaches – logistic regression and Darwinian dynamics – to explore theoretically how a behaviour with crucial physiological function might evolve into a coping behaviour. We apply the method to preening in colonial seabirds to …

Crosstalk Between Lysophospatidic Acid (Lpa) And Transforming Growth Factor Beta (Tgfβ) In Breast And Ovarian Cancer Cells, Jinhua Wu

Theses and Dissertations

Lysophosphatidic acid (LPA) and transforming growth factor beta (TGFβ) are platelet-derived intercellular mediators of cell proliferation and motility. LPA is a general growth, survival and motility-stimulating factor in mammalian cells. TGFβ prevents proliferation of normal epithelial cells. However, the growth-inhibitory effect of TGFβ is lost or reduced in most malignant cells. Instead, TGFβ promotes migration and invasion of advanced cancer cells. Since LPA and TGFβ are both present in the blood and tumor microenvironments, we were interested in signal integration and functional outcomes in malignant epithelial cells in an LPA and TGFβ co-stimulatory context. In a subset of breast and …

Abundance, Distribution, And Habitat Use Of Sharks In Two Northeast Florida Estuaries, Michael Philip Mccallister

UNF Graduate Theses and Dissertations

Sharks are considered top predators in many marine ecosystems, and can play an important role in structuring those communities. As a result, it is necessary to understand the factors that influence their abundance and distribution. This is particularly important as fishery managers develop fishery management plans for sharks that identify areas that serve as essential fish habitat (EFH). This includes nursery habitat where sharks are born and juveniles spend the early part of their life. However, our understanding of shark habitat use in the northeast Florida waters is limited. The goal of this thesis was to characterize the abundance and …

The Influence Of Seawater And Sulfate Reduction On Phosphate Release From Tidal Wetland Soils In The St. John’S River, Florida, Asher Williams

UNF Graduate Theses and Dissertations

Climate change and increasing sea level elevation are predicted to increase salinity in estuarine tidal wetlands in the Southeastern United States. Since much of the ecosystem function in these areas is predicated upon salinity regimes, many fundamental changes are likely to occur as a result. The influence of salinity and SO4 2- reduction on PO4 3- release from tidal wetland soils was evaluated along a salinity gradient at three sites in The St. John’s River, Florida using both field and laboratorybased methods. Porewater was sampled over the course of 10 months to determine ambient levels of SO4 2- and PO4 …

Population Structure And Nest Success Of Gopher Tortoises (Gopherus Polyphemus), And Vegetative Response To Prescribed Burning In Northeast Florida, Kristine Constance Amatuli

UNF Graduate Theses and Dissertations

A gopher tortoise population on the campus of University of North Florida is part of an ongoing study initiated during the early 1990s, and this project presents data on this population collected during the 2009-2011 field seasons. The project has three major objectives: 1) measure population demographics including density and structure to assess long-term viability and recruitment, 2) evaluate decadal growth rates of individuals by comparing measurements of tortoises captured and marked in the 1990-1994 study done at the same site with those tortoises recaptured during the current study, and 3) assess the effect of prescribed burning on vegetation. In …

Demography And Reproductive Biology Of The Gopher Tortoise (Gopherus Polyphemus) Population At White Oak Plantation, Nassau County, Florida, Julia Rachel Smith

UNF Graduate Theses and Dissertations

The demography and reproductive biology of the gopher tortoise (Gopherus polyphemus) was studied for two years at White Oak Plantation (WOP), located in northeast Florida along the St. Mary’s river. Two sub‐populations were studied in regions I referred to as Site A and Site B. I located 312 burrows and captured 109 different tortoises, either by hand or using bucket traps. Tortoise density was 4.48/ha at Site A and only 1.15/ha at Site B. Juveniles were the most abundant age class overall, while hatchlings were numerous at Site A but virtually absent at Site B. The combined sex ratio for …

Results From An Assesment Survey For School Food Service Directors And School Foodservice Managers Participating In The 2011-2012 South Carolina Farm To School Program, Maciel Ugalde

All Theses

In South Carolina (SC), children aged 10-17 are ranked 13th in the United States for overweight and obesity (33.7%) according to the National Survey of Children's Health 2007. Fruit and vegetable intake in children and adolescents in the United States is below recommended levels (Lorson, Melgar-Quinonez, & Taylor, 2009). In SC, only 15% of the high school students consume fruits and vegetables five or more times per day. Fruit and vegetable consumption has been associated with reduced risk of chronic diseases (Epstein et al., 2001; Knai, Pomerleau, Lock, & McKee, 2006; Reichmann, 2009). Schools are identified as a key setting …

A Coupled Experimental And Computational Approach To Quantify Deleterious Hemodynamics, Vascular Alterations, And Mechanisms Of Long-Term Morbidity In Response To Aortic Coarctati, Arjun Menon, David C. Wendell, Hongfeng Wang, Thomas J. Eddinger, Jeffrey M. Toth, Ronak Jashwant Dholakia, Paul M. Larsen, Eric S. Jensen, John F. Ladisa

Biomedical Engineering Faculty Research and Publications

Introduction

Coarctation of the aorta (CoA) is associated with morbidity despite treatment. Although mechanisms remain elusive, abnormal hemodynamics and vascular biomechanics are implicated. We present a novel approach that facilitates quantification of coarctation-induced mechanical alterations and their impact on vascular structure and function, without genetic or confounding factors.

Methods

Rabbits underwent thoracic CoA at 10 weeks of age (~ 9 human years) to induce a 20 mm Hg blood pressure (BP) gradient using permanent or dissolvable suture thereby replicating untreated and corrected CoA. Computational fluid dynamics (CFD) was performed using imaging and BP data at 32 weeks to quantify velocity, …

Contents, Discovery Editors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 13 2012, Several Authors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Letter From The Dean, Michael Vayda

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

The Arkansas Meat Goat Enterprise Budget, Jessica House, H. I. Goodwin

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Goats have long been the most populous livestock animals on the planet. They have been a staple food for many low-income countries. The United States has a growing demand for goat meat. There is an increase in ethnic cultures that desire goat meat as well as a growing interest from the general population. Goat meat is a healthy alternative compared to traditional red meats. Goats also pair well with other livestock animals due to their wide range of palatable feeds. They are commonly used in cattle operations for weed control because of their ability to consume noxious weeds. There is …