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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 …

Electrostatic Charge Polarity Effect On Respiratory Deposition In The Glass Bead Tracheobronchial Airways Model, Mohammed Ali, Malay K. Mazumder, Rama N. Reddy, Mariofanna Milanova, Jing Zhang, Alexandru S. Biris

Journal of the Arkansas Academy of Science

The effects of unipolar and bipolar electrostatic charges on the deposition efficiency of therapeutic aerosols in the physical model of human tracheobronchial (TB) airways have been investigated. Respirable size aerosol particles were generated by a commonly prescribed and commercially available nebulizer and charged by a corona charger and then their size and charge distributions were characterized by an Electronic Single Particle Aerodynamic Relaxation Time analyzer to study the drug aerosol particles' deposition pattern. The experiments were performed with a glass bead tracheobronchial model (GBTBM) (physical model) which was designed and developed based upon widely used and adopted dichotomous lung morphometric …

Sustained Il-6/Stat-3 Signaling In Cholangiocarcinoma Cells Due To Socs-3 Epigenetic Silencing., Hajime Isomoto, Justin L. Mott, Shogo Kobayashi, Nathan W. Werneburg, Steve F. Bronk, Serge Haan, Gregory J. Gores

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND & AIMS: Interleukin 6 (IL-6)-mediated signal transducers and activators of transcription 3 (STAT-3) phosphorylation (activation) is aberrantly sustained in cholangiocarcinoma cells resulting in enhanced myeloid cell leukemia 1 (Mcl-1) expression and resistance to apoptosis. Because suppressor of cytokine signaling 3 (SOCS) controls the IL-6/STAT-3 signaling pathway by a classic feedback loop, the aims of this study were to examine SOCS-3 regulation in human cholangiocarcinoma.

METHODS: SOCS-3 expression was assessed in human cholangiocarcinoma tissue and the Mz-ChA-1 and CCLP1 human cholangiocarcinoma cell lines.

RESULTS: An inverse correlation was observed between phospho-STAT-3 and SOCS-3 protein expression in cholangiocarcinoma. In those cancers …

Characterization Of Human Immunodeficiency Virus Type 1 Monomeric And Trimeric Gp120 Glycoproteins Stabilized In The Cd4-Bound State: Antigenicity, Biophysics, And Immunogenicity, Barna Dey, Marie Pancera, Krisha Svehla, Yuuei Shu, Shi-Hua Xiang, Jeffrey Vainshtein, Yuxing Li, Joseph Sodroski, Peter D. Kwong, John R. Mascola, Richard Wyatt

Nebraska Center for Virology: Faculty Publications

The human immunodeficiency virus type 1 exterior gp120 envelope glycoprotein is highly flexible, and this flexibility may contribute to the inability of monomeric gp120 immunogens to elicit broadly neutralizing antibodies. We previously showed that an S375W modification of a critical interfacial cavity central to the primary receptor binding site, the Phe43 cavity, stabilizes gp120 into the CD4-bound state. However, the immunological effects of this cavity-altering replacement were never tested. Subsequently, we screened other mutations that, along with the S375W alteration, might further stabilize the CD4-bound state. Here, we define a selected second cavity-altering replacement, T257S, and analyze the double mutations …

Georgeoral Immunization Of Rhesus Macaques With Adenoviral Hiv Vaccines Using Enteric-Coated Capsules, George T. Mercier, Pramod N. Nehete, Marco F. Passeri, Bharti N. Nehete, Eric A. Weaver, Nancy Smyth Templeton, Kimberly Schluns, Stephanie S. Buchl, K. Jagannadha Sastry, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Targeted delivery of vaccine candidates to the gastrointestinal (GI) tract holds potential for mucosal immunization, particularly against mucosal pathogens like the human immunodeficiency virus (HIV). Among the different strategies for achieving targeted release in the GI tract, namely the small intestine, pH sensitive enteric coating polymers have been shown to protect solid oral dosage forms from the harsh digestive environment of the stomach and dissolve relatively rapidly in the small intestine by taking advantage of the luminal pH gradient. We developed an enteric polymethacrylate formulation for coating hydroxy-propyl-methyl-cellulose (HPMC) capsules containing lyophilized Adenoviral type 5 (Ad5) vectors expressing HIV-1 gag …

Genetic Microheterogeneity And Phenotypic Variation Of Helicobacter Pylori Arginase In Clinical Isolates, Justin Hovey, Emily Watson, Melanie Langford, Ellen Hildebrandt, Sangeetha Bathala, Jeffrey Bolland, Domenico Spadafora, George Mendz, David Mcgee

School of Biological Sciences: Faculty Publications

Background: Clinical isolates of the gastric pathogen Helicobacter pylori display a high level of genetic macro- and microheterogeneity, featuring a panmictic, rather than clonal structure. The ability of H. pylori to survive the stomach acid is due, in part, to the arginase-urease enzyme system. Arginase (RocF) hydrolyzes L-arginine to L-ornithine and urea, and urease hydrolyzes urea to carbon dioxide and ammonium, which can neutralize acid.

Results: The degree of variation in arginase was explored at the DNA sequence, enzyme activity and protein expression levels. To this end, arginase activity was measured from 73 minimally-passaged clinical isolates and six laboratory-adapted strains …

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 …

Regulation Of The Human Heme Oxygenase-1 Gene, Thomas D. Hock

All ETDs from UAB

The heme oxygenase-1 (HO-1) gene encodes a microsomal enzyme that catalyzes the conversion of heme to carbon monoxide, Iron, and biliverdin. HO-1 transcription is induced upon a plethora of cellular stresses including heme, heavy metal exposure, hy-poxia, oxidative stress and many others. The goal of this work was to explore the molecu-lar regulation of HO-1 transcription. Four DNase 1 hypersensitive sites are detected within the HO-1 promoter extending from ~-40bp to ~-9.2kb relative to the transcription start site. Dimethylsulfate (DMS) in vivo footprinting is shown for two regulatory re-gions and reveals nine protected guanines in all. Mutational analyses indicates that …

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

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 …

The Role Of Complement In The Clearance Of Streptococcus Pneumoniae Through Immune Adherence, Jie Li

All ETDs from UAB

Streptococcus pneumoniae is the most frequently isolated pathogen causing bacteremia in young children and elderly adults. Complement-dependent opsonophagocytosis is thought to be essential to eliminate pneumococci from the circulation. Pneumococci are reported to attach to erythrocytes through immune adherence (IA), a complement and antibody- dependent process that facilitates phagocytosis of pneumococci. In these studies we have determined that protein (chapter 1) and polysaccharide (chapter 2) virulence factors of pneumococci can interfere with this process and that antibody to pneumococci can enhance this process. Using PspA and/or PspC negative strains and complement-deficient mouse sera, we demonstrated that PspA inhibits complement C1q …

Effects Of Specific Alterations In Capsule Structure On Streptococcus Pneumoniae Capsule Assembly And Virulence, Bobbi Xayarath

All ETDs from UAB

The polysaccharide capsules of Streptococcus pneumoniae represent the most important virulence determinant produced by this organism. Ninety-one different serotypes have been identified, but only a small number of these serotypes are responsible for most of the infections caused by S. pneumoniae. The reasons why certain serotypes predominate in infections over others are not well understood. One common serotype found in invasive diseases is type 2, however, it is unclear what characteristics of a type 2 capsule makes strains producing it virulent. The type 2 capsule consists of repeat units made of a backbone of Glc-Rha-Rha-Rha, with a side chain Glc-GlcUA …

Localization And Function Of G2e3, William Samuel Brooks

All ETDs from UAB

A microarray study was performed which identified G2E3 as a novel, putative ubiquitin ligase that was both G2/M-specific in expression and down regulated at the transcriptional level following DNA damage by γ-irradiation. The initial characterization of this protein is described herein. G2E3 is composed of three PHD/RING (plant homoedomain/really interesting new gene) domains within its amino-terminal half and a carboxy-terminal HECT (homologous to E6AP carboxy-terminus) domain. G2E3 is regulated in part by its subcellular localization. The protein normally resides within the nucleoplasm of cultured cells and distinctly within the nucleolus of HeLa cells. G2E3 is a nucleo-cytoplasmic shuttling protein with …

Loss Of Pias3 Expression In Glioblastoma Multiforme Tumors:Implications For Stat-3 Activation And Gene Expression, Emily Claire Brantley

All ETDs from UAB

Glioblastoma multiforme (GBM) is the most common form of cancer in the central nervous system in adults. Because of the infiltrative and aggressive nature of GBM, current treatments including surgical resection, radiation and chemotherapy provide little benefit to patients diagnosed with this tumor. Median survival, after treatment, is less than one year. Despite advances in the basic understanding of cancer biology, this poor prognosis has remained virtually unchanged for several decades. Given the continuing difficulty of clinical treatment of GBMs, a molecular appreciation of relevant signaling pathways has grown. Signal Transducers and Activators of Transcription (STATs) function to activate gene …

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 …

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 …

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 …

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

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 …

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 …

The Role Of Cd5 In Experimental Autoimmune Encephalitomyelitis, Robert C. Axtell

All ETDs from UAB

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 …

A Proteome-Wide Protein Interaction Map For Campylobacter Jejuni, Jodi R. Parrish, Jingkai Yu, Guozhen Liu, Julie A. Hines, Jason E. Chan, Bernie A. Mangiola, Huamei Zhang, Svetlana Pacifico, Farshad Fotouhi, Victor J. Dirita, Trey Ideker, Phillip Andrews, Russell L. Finley Jr

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Data from large-scale protein interaction screens for humans and model eukaryotes have been invaluable for developing systems-level models of biological processes. Despite this value, only a limited amount of interaction data is available for prokaryotes. Here we report the systematic identification of protein interactions for the bacterium Campylobacter jejuni, a food-borne pathogen and a major cause of gastroenteritis worldwide.

Results

Using high-throughput yeast two-hybrid screens we detected and reproduced 11,687 interactions. The resulting interaction map includes 80% of the predicted C. jejuni NCTC11168 proteins and places a large number of poorly characterized proteins into networks that provide initial …

Paediatric Mental Health In Pakistan: A Neglected Avenue, Ali Jawaid, Tauseef-Ur-Rehman

Medical College Documents

No abstract provided.

Tyrosine Phosphorylation Of Villin: Effects On Actin Dynamics, Cell Morphology And Cell Migration, Alok Tomar

Theses and Dissertations (ETD)

Cell migration is a key aspect of many normal and abnormal biological processes, including embryonic development, defense against infections, wound healing, and tumor cell metastasis. In this study we demonstrate that an epithelial cell actin-binding protein, villin, plays a crucial role in the process of cell migration. Overexpression of villin in doxycyline-regulated HeLa Tet-off and MDCK Tet-off cells enhanced cell migration. We further demonstrate that tyrosine phosphorylation of villin by c-src is required for villin-induced cell migration. Previously, we identified four tyrosine phosphorylation sites in the amino-terminal domain of villin. I further identified six new sites in the carboxylterminal region …

Appl1 Associates With Trka And Gipc1 And Is Required For Nerve Growth Factor-Mediated Signal Transduction, D. C. Lin, C. Quevedo, N. E. Brewer, A. Bell, J. R. Testa, Mark L. Grimes, F. D. Miller, D. R. Kaplan

Biomedical and Pharmaceutical Sciences Faculty Publications

The neurotrophin receptor TrkA plays critical roles in the nervous system by recruiting signaling molecules that activate pathways required for the growth and survival of neurons. Here, we report APPL1 as a TrkA-associated protein. APPL1 and TrkA coirnmunoprecipitated in sympathetic neurons. We have identified two routes through which this association can occur. APPL1 was isolated as a binding partner for the TrkA-interacting protein GIPC1 from rat brain lysate by mass spectrometry. The PDZ domain of GIPC1 directly engaged the C-terminal sequence of APPL1. This interaction provides a means through which APPL1 may be recruited to TrkA. In addition, the APPL1 …

An In Vitro Model Of Ovarian Cancer: Studying The Effects Of Talc And Pycnogenol®, Amber Renée Buz'zard

Loma Linda University Electronic Theses, Dissertations & Projects

Ovarian cancer is the sixth most common cancer and accounts for more deaths than any other cancer of the female reproductive system. The American Cancer Society has suggested that poor diet, talc and industrial pollutants may increase the risk of developing ovarian cancer. Talc is ubiquitous and concern is raised about its safety, role as a possible carcinogen and known ability to cause irritation and inflammation. Due to the silent nature of ovarian cancer, chemoprevention is a high priority. The most useful chemopreventive compounds will inhibit, delay or reverse carcinogenesis, and can be taken for long periods of time with …

Androgen-Regulated Formation And Degradation Of Gap Junctions In Androgen-Responsive Human Prostate Cancer Cells., Shalini Mitra, Lakshmanan Annamalai, Souvik Chakraborty, Kristen E. Johnson, Xiao-Hong Song, Surinder K. Batra, Parmender P. Mehta

Journal Articles: Biochemistry & Molecular Biology

The constituent proteins of gap junctions, called connexins (Cxs), have a short half-life. Despite this, the physiological stimuli that control the assembly of Cxs into gap junctions and their degradation have remained poorly understood. We show here that in androgen-responsive human prostate cancer cells, androgens control the expression level of Cx32-and hence the extent of gap junction formation-post-translationally. In the absence of androgens, a major fraction of Cx32 is degraded presumably by endoplasmic reticulum-associated degradation, whereas in their presence, this fraction is rescued from degradation. We also show that Cx32 and Cx43 degrade by a similar mechanism. Thus, androgens regulate …

Multiple Domains In Siz Sumo Ligases Contribute To Substrate Selectivity., Alison Reindle, Irina Belichenko, Gwendolyn R Bylebyl, Xiaole L Chen, Nishant Gandhi, Erica S Johnson

Department of Biochemistry and Molecular Biology Faculty Papers

Saccharomyces cerevisiae contains two Siz/PIAS SUMO E3 ligases, Siz1 and Siz2/Nfi1, and one other known ligase, Mms21. Although ubiquitin ligases are highly substrate-specific, the degree to which SUMO ligases target distinct sets of substrates is unknown. Here we show that although Siz1 and Siz2 each have unique substrates in vivo, sumoylation of many substrates can be stimulated by either protein. Furthermore, in the absence of both Siz proteins, many of the same substrates are still sumoylated at low levels. Some of this residual sumoylation depends on MMS21. Siz1 targets its unique substrates through at least two distinct domains. Sumoylation of …

Antimicrobial Effects Of Liquid Anesthetic Isoflurane On Candida Albicans, Viachaslau M. Barodka, Edward Acheampong, Garry Powell, Ludmilla Lobach, David A. Logan, Zahida Parveen, Valerie Armstead, Muhammad Mukhtar

Department of Medicine Faculty Papers

Candida albicans is a dimorphic fungus that can grow in yeast morphology or hyphal form depending on the surrounding environment. This ubiquitous fungus is present in skin and mucus membranes as a potential pathogen that under opportunistic conditions causes a series of systemic and superficial infections known as candidiasis, moniliasis or simply candidiasis. There has been a steady increase in the prevalence of candidiasis that is expressed in more virulent forms of infection. Although candidiasis is commonly manifested as mucocutaneous disease, life-threatening systemic invasion by this fungus can occur in every part of the body. The severity of candidal infections …

Cdx4 Dysregulates Hox Gene Expression And Generates Acute Myeloid Leukemia Alone And In Cooperation With Meis1a In A Murine Model, Dimple Bansal, Claudia Scholl, Stefan Frohling, Elizabeth Mcdowell, Benjamin H. Lee, Konstanze Döhner, Patricia Ernst

Dartmouth Scholarship

HOX genes have emerged as critical effectors of leukemogenesis, but the mechanisms that regulate their expression in leukemia are not well understood. Recent data suggest that the caudal homeobox transcription factors CDX1, CDX2, and CDX4, developmental regulators of HOX gene expression, may contribute to HOX gene dysregulation in leukemia. We report here that CDX4 is expressed normally in early hematopoietic progenitors and is expressed aberrantly in approximately 25% of acute myeloid leukemia (AML) patient samples. Cdx4 regulates Hox gene expression in the adult murine hematopoietic system and dysregulates Hox genes that are implicated in leukemogenesis. Furthermore, bone marrow progenitors that …