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Full-Text Articles in Medicine and Health Sciences
Molecular Determinants Of Picrotoxin Inhibition, Brian E. Erkkila
Molecular Determinants Of Picrotoxin Inhibition, Brian E. Erkkila
All ETDs from UAB
PTX is a non-competitive antagonist of many LGICs, and its site of action is believed to be within the ion-conducting pore. This study will examine, through the use of mutagenesis, electrophysiology and homology modeling, the binding interaction between the LGIC receptors and the PTX molecule. The data provides evidence that an interaction between the PTX molecule and uncharged polar amino acids at the 6’ level of the M2 transmembrane domain are essential for PTX inhibition. While the work will focus on the γ-aminobutyric type A receptor, the pharmacological and structural relevance is attributable to the LGIC family as a whole.
The Role Of Chloride In The Volume Regulation Of Human Glioma Cells, Nola Jean Ernest
The Role Of Chloride In The Volume Regulation Of Human Glioma Cells, Nola Jean Ernest
All ETDs from UAB
According to the Central Brain Tumor Registry of the United States, the most common primary brain tumors are gliomas, tumors composed of cells of glial origin, most commonly astrocytes and oligodendrocytes. The most aggressive of these tumors are characterized by hyperproliferation, marked cellular and nuclear atypia, extensive infiltration into surrounding normal brain tissue, and large areas of cell and tissue death. Previous data published by our lab and others suggest that these biological processes may involve regulated cell volume changes. Using cell volume regulation in the presence of an anisosmotic challenge as a model for cell swelling and shrinkage, cell …
Cd8+ T-Lymphocytes And The Control Of Cytomegalovirus Infection Of The Newborn Central Nervous System, Glenn Robert Burgner Bantug
Cd8+ T-Lymphocytes And The Control Of Cytomegalovirus Infection Of The Newborn Central Nervous System, Glenn Robert Burgner Bantug
All ETDs from UAB
Congenital HCMV infection of the developing brain is the leading viral cause of mental retardation and sensorineural hearing loss. To elucidate the pathogenesis of congenital HCMV CNS infections, we developed a small animal model of CMV infection where newborn Balb/c mice are peripherally inoculated with murine cytomegalovirus. In this model we observed transient deficits in cerebellar/hindbrain development as well as the recruitment of peripheral immune effector cells to the CNS parenchyma. CD8+ T-lymphocytes were the predominant mononuclear cellular infiltrates in the brain and immune-depletion of CD8+ cells resulted in increased viral genome copy numbers in the CNS. CD8+ T-lymphocytes exhibited …
Characterization And Functional Analysis Of Usp14, Stephen Lewis Crimmins
Characterization And Functional Analysis Of Usp14, Stephen Lewis Crimmins
All ETDs from UAB
The ubiquitin proteasome system (UPS) is essential for regulated protein degrada-tion, a requirement for numerous neuronal process, including vesicle cycling, neuro-transmitter release, spine morphology, and synaptic plasticity. Better understanding of UPS function in neurons will increase our knowledge of neurological diseases caused by alterations in ubiquitin signaling. I utilized the ataxia (axJ) mice as a tool to study the UPS in the nervous system. The axJ mice have lowered expression of ubiquitin-specific protease 14 (Usp14) in all tissues; this decreased expression results from an intracisternal-A particle insertion into Usp14. The axJ mice are phenotypically indistinguishable from wild type littermates at …
Characterization Of A Novel Acetyltransferase Found Only In Pathogenic Strains Of Mycobacterium Tuberculosis, David K. Crossman
Characterization Of A Novel Acetyltransferase Found Only In Pathogenic Strains Of Mycobacterium Tuberculosis, David K. Crossman
All ETDs from UAB
Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), is still a major threat to the human population. Roughly one third of the world population is asymptomatically infected and two million people die each year of TB. Effective treatments are available as a multi-drug regimen, but there is an ever increasing problem with the rise of multi-drug resistant strains that newer drug targets and a better understanding of how M. tuberculosis affects the host need to be elucidated. The primary target of M. tuberculosis in the human host is the macrophage where M. tuberculosis secretes virulence factors that inhibit various signal …
The Role Of The Cytoskeleon In Achr Clustering, G Clement Dobbins
The Role Of The Cytoskeleon In Achr Clustering, G Clement Dobbins
All ETDs from UAB
The human brain contains billions of neurons which are designed to receive and integrate a range of electrical and biochemical signals. The ability to convey information between these cells depends on synapses. A precise apposition between the pre and post synapse must exist for efficient transmission to occur. The neuromuscular junction (NMJ) has become a model for studying synaptogenesis. Although much is known about the steps in NMJ formation, only recently have there been insights into the mechanism behind NMJ development. Much of this research has focused on how acetylcholine receptors (AChRs) at the postsynapse form clusters directly apposed to …
A Study Into The Protein/Protein Interactions Involved In Hiv-1 Capsid Assembly, Chanel Catherine Douglas
A Study Into The Protein/Protein Interactions Involved In Hiv-1 Capsid Assembly, Chanel Catherine Douglas
All ETDs from UAB
The aim of this work was to build an understanding of the protein/protein interactions involved in HIV-1 capsid assembly as it relates to the condensation of capsid within the virion. This was undertaken in an attempt to (i) understand how capsid subunits recognize and interact with each other, (ii) gain insight into the protein-protein interactions involved in the process, and (iii) determine if the protein-protein interactions involved in virus cap-sid assembly can be used as a target for viral inhibition. Within this dissertation you will find two approaches to this investigation. The first examines the role of electrostatics in the …
Visualizing The Function And Migration Of T Cells, Kari J. Dugger
Visualizing The Function And Migration Of T Cells, Kari J. Dugger
All ETDs from UAB
Lymphocytes are highly mobile cells that can travel throughout the body in response to a multitude of stimuli. Identifying lymphocyte trafficking patterns in vivo is essential for a complete understanding of immune function. Cell-cell and cell-tissue interactions in immune development and in lymphocyte response to stimuli can be comprehended with these investigations. Although the location of cell populations in various tissues at any given point in time may be investigated by techniques such as flow cytometry and immunofluorescence, these methods are not easily used in the assessment of dynamic cell migration patterns in vivo. In the past years, technologies for …
Protease Dysregulation: Role In Neutrophilic Inflammation In Cystic Fibrosis, Amit Gaggar
Protease Dysregulation: Role In Neutrophilic Inflammation In Cystic Fibrosis, Amit Gaggar
All ETDs from UAB
Cystic fibrosis (CF) is a lethal disorder characterized by abnormal epithelial ion transport; this disorder is characterized by an ongoing airway remodeling and neutrophilic inflammation. Much of the airway remodeling is due to activation of a group of enzymes known as proteases; human neutrophil elastase (HNE) is a prominent protease found in the CF airway. While specific cytokines/chemokines are well-known for their role in the inflammation seen in CF, it is unknown how the protease-rich environment in CF lung disease influences airway inflammation. Recently, our group has characterized a novel collagen-derived fragment, proline-glycine-proline (PGP), which causes neutrophil influx through mechanisms …
Pneumococcal Choline-Binding Protein A: Its Role In Virulence And Its Utility As A Streptococcus Pneumoniae Vaccine Antigen, David Tawayne Glover
Pneumococcal Choline-Binding Protein A: Its Role In Virulence And Its Utility As A Streptococcus Pneumoniae Vaccine Antigen, David Tawayne Glover
All ETDs from UAB
Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide. S. pneumoniae is a leading cause of pneumonia, meningitis, septicemia, and otitis media. Although all age groups can be affected, children and the elderly are espccially susceptible to infection. Currently there is a conjugate vaccine available for use, but this vaccine only contains capsular polysaccahride antigens from the seven most prevelant S. pneumoniae serotypes. The use of the conjugate vaccine has led to serotype shift, with more disease being caused by non-vaccine serotype bacteria. The studies presented in this dissertation identify and characterize a novel S. penumoniae vaccine candidate …
Protein Interaction And Cell Surface Trafficking Differences Between Wild-Type And Δf508 Cystic Fibrosis Transmembrane Conductance Regulator, Rebecca F. Goldstein
Protein Interaction And Cell Surface Trafficking Differences Between Wild-Type And Δf508 Cystic Fibrosis Transmembrane Conductance Regulator, Rebecca F. Goldstein
All ETDs from UAB
Cystic fibrosis (CF) is caused by mutation of one protein, the cystic fibrosis transmembrane conductance regulator (CFTR), which normally functions as a chloride channel at the apical surface of epithelial cells. The most common CFTR mutation results in the deletion of a single amino acid (phenylalanine) at position 508, which causes the protein to fold improperly. The ΔF508 CFTR is a temperature-sensitive (TS) processing mutant: At the restrictive temperature, 37°C, ΔF508 CFTR misfolds in the endoplasmic reticulum (ER) and is degraded, but at the permissive temperature, 27°C, it is “rescued” from degradation (rΔF508). In particular, rΔF508 CFTR folds correctly enough …
A Role For P63 In The Regulati On Of Cell Cycle Progression And Cell Death, Eric Scott Helton
A Role For P63 In The Regulati On Of Cell Cycle Progression And Cell Death, Eric Scott Helton
All ETDs from UAB
p63 is a member of the p53 family of transcription factors that is a critical regulator of epithelial development. Studies have shown that p63 does not appear to function as a classical tumor suppressor like p53. Instead, the expression pattern of p63 in cancers suggests that p63 retains the potential to function as either a tumor suppressor or an onco-protein. Here, we provide evidence describing the transcriptional activity of the p63 isoforms and provide mechanisms whereby p63 function is regulated in a context dependent manner. Our data shows that both the ΔNp63 and TAp63 variants retain the potential to regulate …
Prostate Cancer Chemoprevention With Genistein And Resveratrol In Models Of Spontaneously Developing Prostate Cancer, Curt E. Harper
Prostate Cancer Chemoprevention With Genistein And Resveratrol In Models Of Spontaneously Developing Prostate Cancer, Curt E. Harper
All ETDs from UAB
Prostate cancer is the second leading cause of cancer-related death among men in the United States. The goal of this research was to investigate the potential of three nutriceutical polyphenols, genistein, resveratrol, and epigallocatechin-3-gallate (EGCG), to suppress prostate cancer. Cancer chemoprevention and mechanism of action studies were carried out in transgenic models of prostate cancer. In TRansgenic Adenocarcinoma of the Mouse Prostate (TRAMP) model, resveratrol suppressed poorly differentiated tumors by 86%, whereas EGCG suppressed precancerous lesions, but failed to prevent late-stage prostate cancer. Agents that were chemopreventive in the TRAMP model were subsequently evaluated alone, and in combination, in the …
Characterization Of A Global Regulatory Pathway In Streptococcus Pneumoniae, Greer E. Kaufman
Characterization Of A Global Regulatory Pathway In Streptococcus Pneumoniae, Greer E. Kaufman
All ETDs from UAB
Streptococcus pneumoniae is a versatile organism that adapts to many different environments in the host. S. pneumoniae can asymptomatically colonize the nasopharynx of humans. However, dissemination of the bacterium from the nasopharynx to different locations in the body can lead to invasive diseases such as pneumonia, bacteremia, and meningitis. How S. pneumoniae modulates factors that are important for survival in these niches has not been well characterized. In the studies described here, we propose that S. pneumoniae may modulate gene expression in these niches by sensing the different glu-cose concentrations via carbon catabolite control protein A (CcpA). Initially we characterized …
On The Immunological Roles Of Tlt2 And Hsh2, R Glenn King
On The Immunological Roles Of Tlt2 And Hsh2, R Glenn King
All ETDs from UAB
The evolution of multicellular organisms necessitated the ability to detect and remove harmful parasitic microorganisms from the host. This simple requirement for self non-self discrimination has evolved in vertebrates into an elaborate system consisting of a variety of effector mechanisms to perform this process. The immune system is often described as consisting of two distinct yet complimentary components, the innate and adaptive immune systems. It is now recognized that the immune system relies on the highly coordinated interplay between a variety of cell types which cooperate to maintain the health of the organism. The work outlined in this dissertation addresses …
The Effect Of The Aml1-Eto Translocation On Cell Cycle Tumor Suppressor Gene Function, Rose Marie Ko
The Effect Of The Aml1-Eto Translocation On Cell Cycle Tumor Suppressor Gene Function, Rose Marie Ko
All ETDs from UAB
The t(8;21)(q22;q22) AML1-ETO translocation is one of the most frequent translocations in acute myeloid leukemia (AML), occurring in approximately 12% of cases. Our laboratory has generated a mouse model in which AML1-ETO is expressed in hematopoietic progenitor cells using a retroviral vector and assayed using bone marrow transplantation. Animals transplanted with AML1-ETO-expressing cells failed to develop leukemia. However, AML1-ETO promoted significant expansion of immature myeloid cells suggesting a “pre-leukemic” state that requires secondary mutations for disease progression. In addition, analysis of cell cycle kinetics in AML1-ETOexpressing myeloid progenitor cells showed that AML1- ETO slowed G1 to S phase progression compared …
Mcmv Induced Cerebellar Maldevelopment, Thadeus B. Koontz
Mcmv Induced Cerebellar Maldevelopment, Thadeus B. Koontz
All ETDs from UAB
Congenital Human Cytomegalovirus (HCMV) infection represents a significant cause of morbidity and mortality in infants and children. While most of the systemic damage incurred by the infant in the course of the infection resolves without permanent consequence, the pathological manifestations of infection in the central nervous system (CNS) are often permanent. Children born with congenital HCMV infection may exhibit hearing loss and cognitive impairment in various degrees. These neurological disabilities are correlated with pathological findings in various permutations including infection of the inner ear, ventricular calcifications, ventriculomegaly, microgyria, lissencephaly, and cerebellar hypoplasia. To develop a therapeutic or preventive strategy, HCMV …
Directing Akt And Gsk3ss: Molecular Insights Into Cell Signaling And Survival, Gordon P. Meares
Directing Akt And Gsk3ss: Molecular Insights Into Cell Signaling And Survival, Gordon P. Meares
All ETDs from UAB
Proper regulation of survival signaling is critical for all organisms. One important signaling cascade involved in the coordinated effort to control signals influencing cell fate is the phosphatidylinositol 3-kinase (PI3K)-Akt-glycogen synthase kinase 3β (GSK3β) signaling cascade. Following activation by growth factors the PI3K-Akt pathway promotes cell survival and, cell death is facilitated following inhibition of Akt. Many factors influence the function of the Akt-GSK3β signaling dyad, including phosphorylation, protein complex formation and subcellular localization. Previous work had demonstrated that the 90kDa heat shock protein, HSP90, directly binds and stabilizes Akt. Furthermore, several heat shock proteins including HSP90 and HSP105 can …
The Function Of Hiv-1 A-Loop On Primer Selection, Na Ni
The Function Of Hiv-1 A-Loop On Primer Selection, Na Ni
All ETDs from UAB
Reverse transcription is the hallmark of retroviruses, such as HIV-1. A cellular tRNA bound to the primer binding site region (PBS) is used for initiation of reverse transcription. HIV-1 specially selects tRNALys3 as primer, although changing the PBS can force HIV-1 to use alternative tRNAs as a primer. However, HIV-1 reverts back to use tRNALys3 following in vitro replication. The A-loop, located upstream of PBS, interacts with the anti-codon of primer tRNA. The inclusion of A-loop modification has been shown to stabilize the utilization of some alternative tRNAs. The studies in this dissertation focus on further defining the role of …
Regulation Of Vertebrate Gastrulation By Erbb Signaling, Shuyi Nie
Regulation Of Vertebrate Gastrulation By Erbb Signaling, Shuyi Nie
All ETDs from UAB
ErbB receptor tyrosine kinases have long been implicated in cancer formation and progression by regulating cell division, migration, and survival. ErbBs are also essential in multiple processes during invertebrate development; however, their activities during vertebrate embryogenesis are not well understood. For functional characterization of ErbB signaling during vertebrate development, frog model Xenopus laevis was used in our studies. The expression pattern and the general activities of ErbB receptors during early frog development were first analyzed and results shown that ErbBs regulate gastrulation, somite organization and head patterning. As gastrulation is the first major morphogenetic event in vertebrate development, I focused …
Trafficking Of Hantaviral Nucleocapsid Proteins, Harish N. Ramanathan
Trafficking Of Hantaviral Nucleocapsid Proteins, Harish N. Ramanathan
All ETDs from UAB
Hantaviruses are enveloped, negative-sense RNA viruses belonging to genus Hantavirus, within the family Bunyaviridae. Hantaviruses include many serious human pathogens and are classified as Old and New World based on the geographic distribution of rodent reservoirs and their ability to in induce distinct illnesses in humans. Currently there are no reservoirs known for hantaviruses other than the rodents. Human transmission of hantaviruses occurs via inhalation of aerosolized rodent excreta leading to hemorrhagic fever with renal syndrome (HFRS) or hantavirus pulmonary syndrome (HPS). Hantavirus genome consists of small (S), medium (M) and large (L) segments that encode nucleocapsid (N) protein, two …
The Role Of Complement In Experimental Autoimmune Uveitis, Russell W. Read
The Role Of Complement In Experimental Autoimmune Uveitis, Russell W. Read
All ETDs from UAB
The complement system has been increasingly implicated in the pathophysiology of autoimmune disease. Complement expression in the normal human eye had not been previously completely defined. We performed immunohistochemical studies for membrane complement proteins in normal human retina to provide a baseline for future studies. We found expression of the anaphylatoxin receptors, CD55, and CD59 in the inner retina and CD46 in a polarized fashion on the retinal pigment epithelium. Previous studies in uveitis have shown activated fragments of complement in human eyes with uveitis and animal models have shown an effect on disease by complement depletion with cobra venom …
In Vivo Imaging Studies In Animal Models Of Myocardial Infarction With And Without Cell Injections, Balazs Ruzsics
In Vivo Imaging Studies In Animal Models Of Myocardial Infarction With And Without Cell Injections, Balazs Ruzsics
All ETDs from UAB
After prolonged myocardial ischemia, myocardial infarction occurs. Several tissue changes are associated with myocardial infarction and iron labeled cell injections. In the present thesis our major aim was to develop methods to monitor these tissue changes with MRI and MDCT. In the first chapter we used transendocardial injection to deliver iron labeled allogen skeletal myoblasts one week after myocardial infarction. Our goal was to identify the cells and/or injection sites in the myocardium. We used our new Tissue Characterization Mapping method to delineate tissue edema and hemorrhage in the myocardium. The T2 weighted signal intensity enhancement, T2w SIE region was …
Bacillus Anthracis Spore-Host Interactions, Melissa K. Swiecki
Bacillus Anthracis Spore-Host Interactions, Melissa K. Swiecki
All ETDs from UAB
The use of Bacillus anthracis as a bioweapon depends on the dispersal of its spores into the environment, entrance into the body, spore uptake by human host cells, germination of the spores in the host and the pathological consequences of the virulence factors produced by the vegetative cells. Prior to 2001, very little was known about the mechanisms of spore entry into the host, including targeting cell types at airway, digestive and skin surfaces, potential spore receptors on these cells and spore encounters with cellular and humoral elements of the innate and adaptive immune systems. To this end, we have …
The Role Of Cd5 In Experimental Autoimmune Encephalitomyelitis, Robert C. Axtell
The Role Of Cd5 In Experimental Autoimmune Encephalitomyelitis, Robert C. Axtell
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The regulation of activation, differentiation and persistence of effector T-cells are critical for the development of Experimental Autoimmune Encephalomyelitis (EAE), the animal model of Multiple Sclerosis. Until now, the function of CD5 was accepted to be a negative regulator of T-cell activation. This dissertation reports that CD5 has an addi-tional role in T-cell responses, which is to promote cell survival. Observations from EAE experiments revealed that mice deficient in CD5 exhibited decreased disease severity which was associated with the inability of activated T-cells to survive. Moreover, block-ing the engagement of CD5 in mice led to enhanced activation induced cell death …
Primer Selection Of E. Coli Trna Lys,3 By Human Immunodeficiency Virus Type-1, Anna Mcculley
Primer Selection Of E. Coli Trna Lys,3 By Human Immunodeficiency Virus Type-1, Anna Mcculley
All ETDs from UAB
Human immunodeficiency virus (HIV) is the cause of acquired immunodeficiency syndrome (AIDS). HIV replication includes the notable process of reverse transcription, a conversion of RNA to DNA. Reverse transcription is initiated from a primer by a viral enzyme, reverse transcriptase. The primer, tRNALys,3, is selected from the cytoplasm of an infected cell, annealed via the 3’ terminal 18-nucleotides to the viral primer binding site (PBS), and used in a subsequent infection. The mechanism of primer selection has not been determined although numerous studies have been performed. This has been hampered by the challenge of tRNALys,3 manipulation in the cell and …
Increased Hexosamine Biosynthesis And Protein O-Glcnac Protect Isolated Rat Heart From Ischemia/Reperfusion Injury, Jia Liu
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Increased levels of protein-associated O-linked N-acetylglucosamine (O-GlcNAc) have been correlated with increased tolerance to stress. Therefore the goal of this study was to determine whether enhanced flux through the hexosamine biosynthesis pathway (HBP), which leads to elevated levels of O-GlcNAc, increased the tolerance of the heart to ischemia and reperfusion (I/R). Hearts from male rats were isolated and perfused with Krebs-Henseliet buffer containing 5mM glucose, and global, no-flow ischemia was induced for 20min followed by 60 min reperfusion. 20 min pre-treatment with 10 mM glucosamine, which enters the HBP directly, significantly improved functional recovery and decreased cardiac Troponin I release …
Kiss1 Metastasis Suppressor Secretion Is Required For Metastasis Suppression, Kevin T. Nash
Kiss1 Metastasis Suppressor Secretion Is Required For Metastasis Suppression, Kevin T. Nash
All ETDs from UAB
Failure to reduce the number of cancer deaths over the last 50 years is due to the inability to selectively target metastatic disease. Recently, the KISS1 metastasis suppressor has emerged as a promising molecular agent for the management of metastatic disease. Although KISS1 has been implicated in the regulation of the metastatic phenotype in human cancers and in in vivo mouse models, little is known about its mechanism. Recent evidence suggests that KISS1 is a neuropeptide that is processed and secreted to interact with its cognate receptor GPR54 in the hypothalamus to trigger puberty and maintain the reproductive state. However, …
Interference With Hiv-1 Primer Selection By Sirna Directed To The Hiv-1 Primer Binding Site, Wenlong Han
Interference With Hiv-1 Primer Selection By Sirna Directed To The Hiv-1 Primer Binding Site, Wenlong Han
All ETDs from UAB
The replication of Human immunodeficiency virus type 1 (HIV-1) is characterized by the process of reverse transcription, which converts the viral RNA genome into a DNA intermediate prior to integration into the host cell chromosome. The initiation of reverse transcription needs a cellular tRNA primer, which binds to a region in the viral RNA genome, designated as the primer binding site (PBS). The 18-nucleotide PBS region of HIV-1, which is complementary to the 3′ terminal 18 nucleotides of tRNALys,3, is absolutely conserved among all HIV-1. The highly conserved PBS is a very good target for HIV-1 therapy. My dissertation research …
Modulation Of Cell Signaling By Tomoregulins In Embryogenesis And Cancer, Paul William Harms
Modulation Of Cell Signaling By Tomoregulins In Embryogenesis And Cancer, Paul William Harms
All ETDs from UAB
Growth factor signals often regulate similar cellular processes both during embryogenesis and in adult homeostasis. Stringent control of these signals ensures proper embryonic development and correct cell physiology in mature individuals. Recently, a family of two members of Tomoregulin (or transmembrane protein with epidermal growth factor-like and two follistatin domains [TMEFF]) was found to interact with transforming growth factor-β (TGF-β) and ErbB signaling pathways, both of which are implicated in development and in cancer biology in the adult. The function as well as the mechanisms of TMEFFs in modulating these two signals has not been elucidated in detail. In this …