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Glutamate Regulation In The Hippocampal Trisynaptic Pathway In Aging And Status Epilepticus, Michelle Lee Stephens

University of Kentucky Doctoral Dissertations

A positive correlation exists between increasing age and the incidence of hippocampal-associated dysfunction and disease. Normal L-glutamate neurotransmission is absolutely critical for hippocampal function, while abnormal glutamate neurotransmission has been implicated in many neurodegenerative diseases. Previous studies, overwhelmingly utilizing ex vivo methods, have filled the literature with contradicting reports about hippocampal glutamate regulation during aging. For our studies, enzyme-based ceramic microelectrode arrays (MEA) were used for rapid (2 Hz) measurements of extracellular glutamate in the hippocampal trisynaptic pathway of young (3-6 months), late-middle aged (18 mo.) and aged (24 mo.) urethane-anesthetized Fischer 344 rats. Compared to young animals, glutamate terminals …

Pyramidobacter Piscolens Gen. Nov., Sp. Nov., A Member Of The Phylum ‘Synergistetes’ Isolated From The Human Oral Cavity, Julia Downes, Sonia R. Vartoukian, Floyd E. Dewhirst, Jacques Izard, Tsute Chen, Wen-Han Yu, Iain C. Sutcliffe, William G. Wade

Department of Food Science and Technology: Faculty Publications

Four strains of anaerobic, gram-negative bacilli isolated from the human oral cavity were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group distinct from any species with validly published names. 16S rRNA and 23S rRNA gene sequence analyses and DNA–DNA reassociation data revealed that the strains constituted a novel group within the phylum ‘Synergistetes’ and were most closely related to Jonquetella anthropi. Two libraries of randomly cloned DNA were prepared from strain W5455T and were sequenced to provide a genome survey as a resource for metagenomic studies. A new genus …

Cryo-Electron Tomography Elucidates The Molecular Architecture Of Treponema Pallidum, The Syphilis Spirochete, Jacques Izard, Christian Renken, Chyong-Ere Hsieh, Daniel C. Desrosiers, Star Dunham-Ems, Carson La Vake, Linda L. Gebhardt, Ronald J. Limberger, David L. Cox, Michael Marko, Justin D. Radolf

Department of Food Science and Technology: Faculty Publications

Cryo-electron tomography (CET) was used to examine the native cellular organization of Treponema pallidum, the syphilis spirochete. T. pallidum cells appeared to form flat waves, did not contain an outer coat and, except for bulges over the basal bodies and widening in the vicinity of flagellar filaments, displayed a uniform periplasmic space. Although the outer membrane (OM) generally was smooth in contour, OM extrusions and blebs frequently were observed, highlighting the structure’s fluidity and lack of attachment to underlying periplasmic constituents. Cytoplasmic filaments converged from their attachment points opposite the basal bodies to form arrays that ran roughly …

Expression Of Hpv16 E5 Produces Enlarged Nuclei And Polyploidy Through Endoreplication, Lulin Hu, Tamara A. Potapova, Shibo Li, Susannah Rankin, Gary J. Gorbsky, Peter C. Angeletti, Brian P. Ceresa

Nebraska Center for Virology: Faculty Publications

Anogenital cancers and head and neck cancers are causally-associated with infection by high-risk

human papillomavirus (HPV). The mechanism by which high-risk HPVs contribute to

oncogenesis is poorly understood. HPV16 encodes three genes (HPV16 E5, E6, and E7) that can

transform cells when expressed independently. HPV16 E6 and E7 have well-described roles

causing genomic instability and unregulated cell cycle progression. The role of HPV16 E5 in cell

transformation remains to be elucidated. Expression of HPV16 E5 results in enlarged, polyploid

nuclei that are dependent on the level and duration of HPV16 E5 expression. Live-cell imaging

data indicate these changes do not …

Human Papillomavirus 16 E5 Induces Bi-Nucleated Cell Formation By Cell-Cell Fusion, Lulin Ha, Kendra Plafker, Valeriya Vorozhoko, Rosemary E. Zuna, Marie H. Hanigan, Gary J. Gorbsky, Scott M. Plafker, Peter C. Angeletti, Brian P. Ceresa

Nebraska Center for Virology: Faculty Publications

Human Papillomaviruses (HPV) 16 is a DNA virus encoding three oncogenes – E5, E6, and E7. The E6 and E7 proteins have well-established roles as inhibitors of tumor suppression, but the contribution of E5 to malignant transformation is controversial. Using spontaneously immortalized human keratinocytes (HaCaT cells), we demonstrate that expression of HPV16 E5 is necessary and sufficient for the formation of bi-nucleated cells, a common characteristic of precancerous cervical lesions. Expression of E5 from non-carcinogenic HPV6b does not produce bi-nucleate cells. Video microscopy and biochemical analyses reveal that bi-nucleates arise through cell-cell fusion. Although most E5-induced bi-nucleates fail to propagate, …

A Comparative Study Of Hiv-1 Clade C Env Evolution In A Zambian Infant With An Infected Rhesus Macaque During Disease Progression, For Yue Tso, Federico G. Hoffmann, Damien C. Tully, Philippe Lemey, Robert A. Rasmussen, Hong Zhang, Ruth M. Ruprecht, Charles Wood

Nebraska Center for Virology: Faculty Publications

Objective—To evaluate whether HIV-1 clade C (HIV-C) envelope variations that arise during disease progression in rhesus macaque model reflect changes that occur naturally in human infection.

Design—An infant macaque was infected with SHIV-1157i, an R5 tropic clade C SHIV (SHIV-C) which expresses a primary HIV-C envelope derived from an infected human infant, and monitored over a five-year period. Genetic variation of the V1-V5 envelope region, which is the main target for humoral immune responses, derived from the infected macaque and infant was examined.

Methods—V1-V5 envelope region were cloned and sequenced from longitudinal PBMC samples collected from the infected macaque and …

Protection Against Mucosal Shiv Challenge By Peptide And Helper-Dependent Adenovirus Vaccines, Eric A. Weaver, Pramod N. Nehete, Bharti P. Nehete, Stephanie J. Buchl, Donna Palmer, David C. Montefiori, Philip Ng, K. Jagannadha Sastry, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Groups of rhesus macaques that had previously been immunized with HIV-1 envelope (env) peptides and first generation adenovirus serotype 5 (FG-Ad5) vaccines expressing the same peptides were immunized intramuscularly three times with helper- dependent adenovirus (HD-Ad) vaccines expressing only the HIV-1 envelope from JRFL. No gag, pol, or other SHIV genes were used for vaccination. One group of the FG-Ad5- immune animals was immunized three times with HD-Ad5 expressing env. One group was immunized by serotype-switching with HD-Ad6, HD-Ad1, and HD-Ad2 expressing env. Previous work demonstrated that serum antibody levels against env were significantly higher in the serotype-switched group than …

A Herpesvirus Encoded Deubiquitinase Is A Novel Neuroinvasive Determinant, Joy I. Lee, Patricia J. Sollars, Scott B. Baver, Gary E. Pickard, Mindy Leelawong, Gregory A. Smith

School of Veterinary and Biomedical Sciences: Faculty Publications

The neuroinvasive property of several alpha-herpesviruses underlies an uncommon infectious process that includes the establishment of life-long latent infections in sensory neurons of the peripheral nervous system. Several herpesvirus proteins are required for replication and dissemination within the nervous system, indicating that exploiting the nervous system as a niche for productive infection requires a specialized set of functions encoded by the virus. Whether initial entry into the nervous system from peripheral tissues also requires specialized viral functions is not known. Here we show that a conserved deubiquitinase domain embedded within a pseudorabies virus structural protein, pUL36, is essential for initial …

Regulation Of Innate Immune Responses By Bovine Herpesvirus 1 And Infected Cell Protein 0 (Bicp0), Clinton Jones

School of Veterinary and Biomedical Sciences: Faculty Publications

Bovine herpesvirus 1 (BoHV-1) infected cell protein 0 (bICP0) is an important transcriptional regulatory protein that stimulates productive infection. In transient transfection assays, bICP0 also inhibits interferon dependent transcription. bICP0 can induce degradation of interferon stimulatory factor 3 (IRF3), a cellular transcription factor that is crucial for activating beta interferon (IFN-β) promoter activity. Recent studies also concluded that interactions between bICP0 and IRF7 inhibit trans-activation of IFN-β promoter activity. The C3HC4 zinc RING (really important new gene) finger located near the amino terminus of bICP0 is important for all known functions of bICP0. A recombinant virus that contains a single …

Spontaneous Idiopathic Arteritis Of The Testicular Artery In Raccoons (Procyon Lotor), A. N. Hamir, M. V. Palmer, H. Li, J. Stasko, D. G. Rogers

School of Veterinary and Biomedical Sciences: Faculty Publications

The testes and the spermatic cord of raccoons (Procyon lotor, kits to adult breeders; n = 48) were examined. Segmental arteritis confined to the extratesticular portions of the testicular artery was present in raccoons of all ages. The arterial changes were seen in laboratory-confined experimental and control animals as well as in wild-caught raccoons. The lesions consisted of proliferative endarteritis with presence of inflammatory cells within the intima, media, and the adventitial regions of most affected vessels. Some aspects of the proliferative arterial lesions were reminiscent of systemic necrotizing vasculitis (polyarteritis nodosa), an immunologically mediated condition of animals and humans. …

The Efficacy Of Surgical Decompression Before 24 Hours Versus 24 To 72 Hours In Patients With Spinal Cord Injury From T1 To L1--With Specific Consideration On Ethics: A Randomized Controlled Trial., Vafa Rahimi-Movaghar, Soheil Saadat, Alexander R Vaccaro, Seyed Mohammad Ghodsi, Mohammad Samadian, Arya Sheykhmozaffari, Seyed Mohammad Safdari, Bahram Keshmirian

Department of Neurosurgery Faculty Papers

BACKGROUND: There is no clear evidence that early decompression following spinal cord injury (SCI) improves neurologic outcome. Such information must be obtained from randomized controlled trials (RCTs). To date no large scale RCT has been performed evaluating the timing of surgical decompression in the setting of thoracolumbar spinal cord injury. A concern for many is the ethical dilemma that a delay in surgery may adversely effect neurologic recovery although this has never been conclusively proven. The purpose of this study is to compare the efficacy of early (before 24 hours) verse late (24-72 hours) surgical decompression in terms of neurological …

The Significance Of Heavy Chain Cdr3 Diversity In The Antibody Response To Polysaccharides, Tamer Mahmoud

All ETDs from UAB

An understanding of the molecular mechanisms involved in the generation of protective antibody responses to polysaccharides associated with pathogenic microorganisms is of importance for improving vaccine design. The heavy chain third complementarity-determining region (HCDR3) of an antibody molecule is at the center of its antigen-binding site and plays a determinative role in antigen recognition. The goal of this dissertation was to investigate the role of HCDR3 diversity and composition on the antibody response to the polysaccharide α 1→3 Dextran (DEX). In the first study, we investigated the role of TdT, a DNA polymerase that plays a major role in generating …

The Acute Onset Of Insulin Resistance In Adipose Tissue Following Trauma And Hemorrhage, Vanessa L. Williams

All ETDs from UAB

Insulin resistance and hyperglycemia are common findings in patients following acute illnesses or injuries, such as surgical trauma, thermal injury, infection, hemorrhage, and sepsis. Insulin has three main target tissues: liver, skeletal muscle, and adipose tissue. Insulin resistance in the liver results in an increase in gluconeogenesis. In skeletal muscle, insulin resistance causes a decrease in insulin-stimulated glucose uptake. However, little is known about the contribution that adipose tissue makes to the insulin resistant state. The goals of the research presented in this dissertation were to: 1) determine whether insulin resistance developed in adipose tissue following acute trauma and hemorrhage; …

Analysis Of Cystic Kidney Disease-Related Genes In Caenorhabditis Elegans, Corey L. Williams

All ETDs from UAB

Cilia are evolutionarily conserved, membrane-bound, microtubule-based organelles found on a diverse array of cell types in eukaryotic organisms. Inherited diseases of cilia protein dysfunction include Nephronophthisis (NPHP), Joubert Syndrome (JBTS), Meckel-Gruber Syndrome (MKS), and Bardet-Biedl Syndrome (BBS). Important insight in the basic cell biological functions of BBS and NPHP proteins has been gained from analysis in the nematode Caenorhabditis elegans. My goal in this dissertation was to model MKS protein function in cilia biology utilizing the powerful genetic malleability of C. elegans. mks-1 and mks-3, the C. elegans homologs of two MKS-associated proteins in humans, were selected for this analysis. …

Axonal Trafficking Of Bmp Signals In Drosophilia Motoneurons, Rebecca Burt Smith

All ETDs from UAB

The Drosophila Bone Morphogenetic Protein (BMP) Glass bottom boat (Gbb) is a ligand for the BMP type II receptor, Wishful thinking (Wit). Mutations in either of these proteins impair synaptic growth at the neuromuscular junction (NMJ). Gbb is a retrograde signal (from target to innervating neuron) that is essential for proper NMJ development and function. Tissue-specific rescue of pathway mutants and immunolocalization experiments indicate that the receptor-ligand interaction occurs at the NMJ, and results in the nuclear accumulation of the phosphorylated form of the transcription factor Mad, indicating that retrograde transport along the axon is critical for pathway activation. We …

The Essential Role Of Macrophages And Tlr Signaling In The Host Response To Mycoplasma Pneumoniae, Jen-Feng Lai

All ETDs from UAB

Several reports have suggested that Mycoplasma pneumoniae (Mp) can contribute importantly to the expression of symptoms in asthmatic human subjects. As a foundation for understanding the interactions between Mp and asthma susceptibility, we first studied the mechanisms by which the host normally eliminated Mp. Mice were inoculated with 4x106 Mp intranasally. Twenty-four hours after inoculation with Mp, subpopulations of CD11b+ macrophages/monocytes had been recruited into the lungs. The clearance of Mp was impaired both in macrophage-depleted and in macrophage-deficient mice. Furthermore, mice deficient in MyD88, a major adaptor for TLR signaling, showed dramatically defective clearance of Mp, associated with reduced …

Mouse Model Of Cooley's Anemia, Yongliang Huo

All ETDs from UAB

β thalassemia major or Cooley’s anemia (CA) is a heterogeneous group of inherited disorders characterized by deficient β globin chain production. Newborns with CA are healthy because of the high fetal hemoglobin (HbF) levels present in their red blood cells (RBCs). As HbF levels decline during the first year of life, patients develop severe anemia that necessitates regular blood transfusion to maintain life. CA has been difficult to model in the mouse due to the lack of a fetal hemoglobin equivalent in the mouse. By utilizing a human fetal to adult delayed hemoglobin switching cassette, I hypothesize that a CA …

Polycistronic Lentiviral Vector For Hit And Run Reprogramming Of Mouse And Human Somatic Cells To Induced Pluripotent Stem Cell, Chia-Wei Chang

All ETDs from UAB

Embryonic stem (ES) cells are pluripotent and, therefore, can differentiate into most if not all somatic cell types. Because of this characteristic, ES cells have great potential for medical therapies. Since the first cloned mammal, Dolly the sheep, was published in 1996 (1), several groups have successfully cloned other animals by the same nuclear transfer method (2). Isogenic ES cell lines can also be established from donor cells by the same technique (3). However, to date there has been no report of successful derivation of human ES cells by nuclear transfer. Based on the cell fusion (4) and nuclear transfer …

The Effect Of Zinc On Cytokine Release And Signal Transduction In Airway Epithelial Cells, Nai-Lin Cheng

All ETDs from UAB

Zinc is an essential cation for life that is involved in numerous physiology and pathophysiology processes. Despite its wide use as a cytoprotective agent in medications, its cellular and molecular mechanisms of action have not been well established. In order to define the potential therapeutic benefit of zinc, I used several Cystic Fibrosis (CF) and non-CF human airway epithelial cell lines as models in my studies. Extracellular zinc caused release calcium from the endoplasmic reticulum though zinc-sensitive Gq-coupled receptor(s) that may subsequently modulate ion channels. In addition, zinc also exhibited anti-inflammatory effects. Zinc inhibited pro-inflammatory molecular TNFα-induced cytokine and chemokine …

Exopolysaccharides Of Mycoplasma Pulmonis, James Michael Daubenspeck

All ETDs from UAB

Capsule has been associated with virulence in numerous bacterial pathogens. The Mollicutes are a host-specific group of pathogens that cause a variety of economically relevant diseases important to man. Mycoplasma pneumoniae is responsible for 2 million cases of atypical pneumonia and 100,000 hospitalizations every year in the United States (Atkinson et al., 2008) (Krause and Taylor-Robinson, 1992). There was a toxic galactan molecule described as early as 1958 in Mycoplasma mycoides subsp. mycoides (Plackett and Buttery, 1958), although no evidence was presented that it was produced by the bacteria. Over the intervening fifty years the evidence to support the production …

Calreticulin And Its Role In Collagen Regulation, Lauren Van Duyn

All ETDs from UAB

Calreticulin (CRT), classically known for its chaperone functions in the endoplasmic reticulum and as a calcium regulator, also is found on the cell surface and in the extracellular matrix. It is involved in many cellular processes including signaling, adhesion, migration, apoptotic cell clearance, gene regulation, and production of a fibronectin matrix. CRT has been suggested to play a role in wound healing and fibrosis. Therefore, these studies investigated the role of CRT in collagen production, an important extracellular matrix molecule in wounding and fibrosis. We demonstrated that CRT regulates collagen through transcription, secretion, and processing. We also investigated the role …

The Role Of Transforming Growth Factor Beta-1 In Bone Remodeling, Yi Tang

All ETDs from UAB

Bone remodeling depends on the precise coordination of bone resorption by the osteoclasts and bone formation by the osteoblasts. It is proposed that osteoclastic bone resorption releases factors to initiate bone formation, thereby, coupling the bone resorption and formation. Mesenchymal stem cells (MSCs) are progenitors of osteoblasts. Recruitment of MSCs in response to osteoclastic bone resorption may be an initial step for bone formation during bone remodeling process. Therefore, we have established an in vitro osteoclastic bone resorption system. Bone resorption condition medium have been tested to identify the factor inducing the migration of human bone marrow mesechymal stem cells …

Characterizing The Role Of Primary Cilia In The Hair Follicle And Skin, Jonathan Merle Lehman

All ETDs from UAB

Primary cilia have been established as a nearly ubiquitous microtubule based signaling organelle, yet their function in many organs, including the hair and skin, is unknown. We hypothesized that the primary cilium would play vital roles in the hair follicle and skin based on the cilium's well characterized interactions with the Shh and Wnt developmental signaling pathways. This dissertation describes our efforts to determine the localization of the primary cilia in the murine hair follicle and assess the function of this organelle in the hair and skin. We used confocal immunofluorescence microscopy to virtually section the entire hair follicle and …

Analysis Of The Malaria Vaccine Potential Of Plasmodium Falciparum Merozoite Surface Protein-3, Stephen James Jordan

All ETDs from UAB

Malaria causes an estimated 1-3 million deaths each year, with the majority of deaths being a result of infection with Plasmodium falciparum. No commercially available vaccine currently exists, but multiple subunit-based vaccines are in development including one based on the promising vaccine candidate P. falciparum Merozoite Surface Protein-3 (PfMSP3). PfMSP3 varies in sequence between P. falciparum isolates, but all variation is restricted to the N-terminal domain. This observation has lead to the development of a PfMSP3-based vaccine comprised solely of the highly conserved, yet poorly immunogenic, C-terminal domain. The rationale for supporting the C-terminal domain relies entirely on its conserved …

Polysaccharide Specific B Cells: A Study Of Their Development And Function, Jeremy B. Foote

All ETDs from UAB

Polysaccharides are important structural components of bacterial capsule and cell walls. Polysaccharide-specific antibodies are an important component of serologic memory capable of protecting against infection by pathogenic microorganisms. An understanding of the biology and function of polysaccharide specific B cells is necessary for formulation of vaccines designed to induce polysaccharide specific memory and long-lived antibody production. The goal of this dissertation was to examine the development of naïve DEX-specific B cells and examine their capacity to generate memory and long-lived plasma cells in response to polysaccharide α 1→3-dextran (DEX), which is expressed by the opportunistic pathogens Enterobacter cloacae, Histoplasma capsulatum …

Mitochondrial Bioenergetics And Cellular Stress, Brian Dranka

All ETDs from UAB

Mitochondria are responsible for most of the energy produced in human tissues, and this is dependent on the reduction of oxygen (O2) to water by the mitochondrial respiratory chain. Defects in mitochondrial energy production are now recognized to be involved in diabetes, cancer, cardiovascular disease, and other pathologies. To date, studies of these defects have employed quantification of O2 consumption in isolated, purified mitochondria. By using this strategy however, the cellular context, role of glycolysis, and normal regulation of mitochondrial function by metabolite availability are lost. Thus, an understanding of how mitochondria function and respond to stimuli in an intact …

Role Of Syndecan-1 As Key Regulator Of Multiple Myeloma Pathogenesis, Yekaterina Borisovna Khotskaya

All ETDs from UAB

Syndecan-1 (CD138), a transmembrane heparan sulfate-bearing proteoglycan, is expressed at high levels on most myeloma cells and is shed into the microenvironment. In patients, high levels of serum syndecan-1 are indicative of poor prognosis and elevation of shed syndecan-1 in animal models dramatically enhances tumor growth, angiogenesis and metastasis. Because syndecan-1 is a key regulator of myeloma pathogenesis, we hypothesized that reduction of syndecan-1 levels expressed by the myeloma cells will block their growth and dissemination. Syndecan-1 knockout and knockdown variants of two human myeloma cell lines, CAG and RPMI-8226, were developed using short hairpin RNA (shRNA) technology. In vitro, …

Impact Of Genetic And Epigenetic Variability In Response To Two Test Drugs 5-Fluorouracil And Lansoprazole, Adam Michael Lee

All ETDs from UAB

Pharmacogenetics has proven to be an invaluable tool in predicting variability in drug response; however, there are numerous incidences where genetics cannot fully explain interindividual drug variability. Other factors, such as the epigenetic mechanism of DNA methylation, may offer an alternate explanation. Therefore, this dissertation focuses on both genetic and epigenetic regulation in order to gain a better understanding of the molecular basis behind drug response variability. Initial investigations focused on the antineoplastic agent 5-Fluorouracil (5-FU), which can produce severe toxicity in patients with deficiency in dihydropyrimidine dehydrogenase (DPD). Genotypic studies have identified >32 sequence variants in the DPYD gene; …

Oxidative Stress-Stimulated Vascular Calcification, Chang Hyun Byon

All ETDs from UAB

Oxidative stress plays a critical role in pathogenesis of atherosclerosis. However, the effect of oxidative stress-induced molecular signaling in development of vascular calcification, a feature of advanced atherosclerosis, has not been defined. Osteogenic differentiation of vascular smooth muscle cells (VSMC) is critical in development of vascular calcification. We determined hydrogen peroxide (H2O2)-induced oxidative stress promoted a phenotypic switch of mouse primary VSMC from contractile to osteogenic phenotype. This effect was associated with increased expression and transactivity of Runx2, a key transcription factor for osteogenic differentiation. Inhibition of Runx2 using short hairpin RNA blocked oxidative stress-induced VSMC calcification. By contrast, adenovirus-mediated …

Intracellular Trafficking Of The Hantaviral Nucleocapsid Protein And Its Function In Modulation Of Immune Signaling, Steven Joe Ontiveros

All ETDs from UAB

Old World and New World hantaviruses, family Bunyaviridae, mature intracellularly within cellular compartments. Although it is generally accepted they assemble and bud in the Golgi apparatus the site remains controversial for New World hantaviruses, because some studies have raised the possibility of their maturation at the plasma membrane. Furthermore, the site of assembly hantaviruses still remains undetermined. The nucleocapsid (N) protein has been proposed to play a key role in facilitating assembly. To gain insight into the assembly pathways of Old World hantaviruses, we examine the intracellular trafficking of the Hantaan (HTN) virus N protein. We show progressive redistribution of …