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Long-Term Clinicopathological Characteristics Of Alpacas Naturally Infected With Bovine Viral Diarrhea Virus Type Ib, D. Bedenice, Edward J. Dubovi, Clayton Kelling, Jamie N Henningson, Christina L. Topliff, N. Parry Jan 2011

Long-Term Clinicopathological Characteristics Of Alpacas Naturally Infected With Bovine Viral Diarrhea Virus Type Ib, D. Bedenice, Edward J. Dubovi, Clayton Kelling, Jamie N Henningson, Christina L. Topliff, N. Parry

School of Veterinary and Biomedical Sciences: Faculty Publications

Background: Substantial bovine viral diarrhea virus (BVDV)-related production losses in North American alpaca herds have been associated with BVDV type Ib infection.

Objectives: To classify and differentiate the long-term clinicopathological characteristics of BVDV type Ib infection of al- paca crias, after natural virus exposure. We hypothesized that persistently infected (PI) alpacas specifically demonstrate growth retardation, clinicopathological evidence of opportunistic infections, and early mortality.

Animals: Thirty-five crias naturally exposed to BVDV (18 acute, 3 chronic, 14 PIs), and 19 healthy cohort controls of 5 northeastern alpaca farms were prospectively evaluated over 2 years (September 2005–September 2008).

Methods: Observational cohort-control study.

Results: …


Detection Of Autoreactive Cd4 T Cells Using Major Histocompatibility Complex Class Ii Dextramers, Chandirasegaran Massilimany, Bijaya Upadhyaya, Arunakumar Gangaplara, Charles Kuszynski, Jay Reddy Jan 2011

Detection Of Autoreactive Cd4 T Cells Using Major Histocompatibility Complex Class Ii Dextramers, Chandirasegaran Massilimany, Bijaya Upadhyaya, Arunakumar Gangaplara, Charles Kuszynski, Jay Reddy

Jay Reddy Publications

Background: Tetramers are useful tools to enumerate the frequencies of antigen-specific T cells. However, unlike CD8 T cells, CD4 T cells - especially self-reactive cells - are challenging to detect with major histocompatibility complex (MHC) class II tetramers because of low frequencies and low affinities of their T cell receptors to MHCpeptide complexes. Here, we report the use of fluorescent multimers, designated MHC dextramers that contain a large number of peptide-MHC complexes per reagent.

Results: The utility of MHC dextramers was evaluated in three autoimmune disease models: 1) proteolipid protein (PLP) 139-151-induced experimental autoimmune encephalomyelitis in SJL/J (H-2s) …


Identification Of A Second Mimicry Epitope From Acanthamoeba Castellanii That Induces Cns Autoimmunity By Generating Cross-Reactive T Cells For Mbp 89–101 In Sjl Mice, Chandirasegaran Massilamany, Oluwatoyin A. Asojo, Arunakumar Gangaplara, David J. Steffen, Jay Reddy Jan 2011

Identification Of A Second Mimicry Epitope From Acanthamoeba Castellanii That Induces Cns Autoimmunity By Generating Cross-Reactive T Cells For Mbp 89–101 In Sjl Mice, Chandirasegaran Massilamany, Oluwatoyin A. Asojo, Arunakumar Gangaplara, David J. Steffen, Jay Reddy

Jay Reddy Publications

We had previously reported that Acanthamoeba castellanii (ACA) contains a mimicry epitope for proteolipid protein 139–151 capable of inducing central nervous system (CNS) autoimmunity in SJL/J mice. We now present evidence that ACA also contains a mimicry epitope for myelin basic protein (MBP) 89–101, a derivative from amoebic nicotinamide adenine dinucleotide dehydrogenase subunit 2 (NAD). The epitope, NAD 108–120, contains a discontinuous stretch of six amino acids in the core region (VVFFKNIILIGFL) sharing 46% identity with MBP 89–101 (VHFFKNIVTPRTP; identical residues are underlined). SJL mice immunized with NAD 108–120 develop encephalomyelitis similar to the disease induced by the cognate peptide. …


Identification Of A Second Mimicry Epitope From Acanthamoeba Castellanii That Induces Cns Autoimmunity By Generating Cross-Reactive T Cells For Mbp 89–101 In Sjl Mice, Chandirasegaran Massilamany, Oluwatoyin A. Asojo, Arunakumar Gangaplara, David J. Steffen, Jay Reddy Jan 2011

Identification Of A Second Mimicry Epitope From Acanthamoeba Castellanii That Induces Cns Autoimmunity By Generating Cross-Reactive T Cells For Mbp 89–101 In Sjl Mice, Chandirasegaran Massilamany, Oluwatoyin A. Asojo, Arunakumar Gangaplara, David J. Steffen, Jay Reddy

Jay Reddy Publications

We had previously reported that Acanthamoeba castellanii (ACA) contains a mimicry epitope for proteolipid protein 139–151 capable of inducing central nervous system (CNS) autoimmunity in SJL/J mice. We now present evidence that ACA also contains a mimicry epitope for myelin basic protein (MBP) 89–101, a derivative from amoebic nicotinamide adenine dinucleotide dehydrogenase subunit 2 (NAD). The epitope, NAD 108–120, contains a discontinuous stretch of six amino acids in the core region (VVFFKNIILIGFL) sharing 46% identity with MBP 89–101 (VHFFKNIVTPRTP; identical residues are underlined). SJL mice immunized with NAD 108–120 develop encephalomyelitis similar to the disease induced by the cognate peptide. …


Rnai Screening Reveals Requirement For Host Cell Secretory Pathway In Infection By Diverse Families Of Negative-Strand Rna Viruses, Debasis Panda, Anshuman Das, Phat X. Dinh, Sakthivel Subramaniam, Debasis Nayak, Nicholas J. Barrows, James L. Pearson, Jesse Thompson, David L. Kelly, Istvan Ladunga, Asit K. Pattnaik Jan 2011

Rnai Screening Reveals Requirement For Host Cell Secretory Pathway In Infection By Diverse Families Of Negative-Strand Rna Viruses, Debasis Panda, Anshuman Das, Phat X. Dinh, Sakthivel Subramaniam, Debasis Nayak, Nicholas J. Barrows, James L. Pearson, Jesse Thompson, David L. Kelly, Istvan Ladunga, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

Negative-strand (NS) RNA viruses comprise many pathogens that cause serious diseases in humans and animals. Despite their clinical importance, little is known about the host factors required for their infection. Using vesicular stomatitis virus (VSV), a prototypic NS RNA virus in the family Rhabdoviridae, we conducted a human genomewide siRNA screen and identified 72 host genes required for viral infection. Many of these identified genes were also required for infection by two other NS RNA viruses, the lymphocytic choriomeningitis virus of the Arenaviridae family and human parainfluenza virus type 3 of the Paramyxoviridae family. Genes affecting different stages of …


Consensus-Based Reporting Standards For Diagnostic Test Accuracy Studies For Paratuberculosis In Ruminants, Ian A. Gardner, Søren S. Nielsen, Richard J. Wittington, Michael T. Collins, Douwe Bakker, Beth Harris, Srinand Sreevatsan, Jason E. Lombard, Raymond Sweeney, David R. Smith, Jerrie Gavalchin, Shigetoshi Eda Jan 2011

Consensus-Based Reporting Standards For Diagnostic Test Accuracy Studies For Paratuberculosis In Ruminants, Ian A. Gardner, Søren S. Nielsen, Richard J. Wittington, Michael T. Collins, Douwe Bakker, Beth Harris, Srinand Sreevatsan, Jason E. Lombard, Raymond Sweeney, David R. Smith, Jerrie Gavalchin, Shigetoshi Eda

School of Veterinary and Biomedical Sciences: Faculty Publications

The Standards for Reporting of Diagnostic Accuracy (STARD) statement was developed to encourage complete and transparent reporting of key elements of test accuracy studies in human medicine. The statement was motivated by widespread evidence of bias in test accuracy studies and the finding that incomplete or absent reporting of items in the STARD checklist was associated with overly optimistic estimates of test performance characteristics. Although STARD principles apply broadly, specific guidelines do not exist to account for unique considerations in livestock studies such as herd tests, potential use of experimental challenge studies, a more diverse group of testing purposes and …


Orbitofrontal Cortex Provides Cross-Modal Valuation Of Self-Generated Stimuli, William A. Cunningham, Ingrid J. Haas, Ashley S. Waggoner Jan 2011

Orbitofrontal Cortex Provides Cross-Modal Valuation Of Self-Generated Stimuli, William A. Cunningham, Ingrid J. Haas, Ashley S. Waggoner

Department of Political Science: Faculty Publications

Prior research has shown that the orbitofrontal cortex (OFC) plays an important role in the representation of the evaluation of stimuli, regardless of stimulus modality. Based on these findings, researchers have proposed that the OFC serves a common currency function, allowing for the direct comparison of different types of perceptual stimuli (e.g. food, drink, money). The present study was designed to extend this research and investigate whether these same regions of OFC that have been identified in previous research are involved in evaluating imagined stimuli. Specifically, we asked participants to draw on prior attitudinal knowledge to generate internal representations of …


Preventing Mother-To-Child Transmission Of Human Immunodeficiency Virus-1 (Hiv-1): Effects Of Intrapartum And Neonatal Single-Dose Nevirapine Prophylaxis And Subsequent Hiv-1 Drug Resistance At Antiretroviral Treatment Initiation, Amanda L. Harmon Jan 2011

Preventing Mother-To-Child Transmission Of Human Immunodeficiency Virus-1 (Hiv-1): Effects Of Intrapartum And Neonatal Single-Dose Nevirapine Prophylaxis And Subsequent Hiv-1 Drug Resistance At Antiretroviral Treatment Initiation, Amanda L. Harmon

CMC Senior Theses

The prevention of mother-to-child transmission is one of the most powerful tools in human immunodeficiency virus type 1 (HIV-1) prevention and has huge potential to improve both maternal and child health. In the absence of any preventative measures, infants born to and breastfed by their HIV-positive mothers have roughly a one-in-three chance of acquiring the infection themselves. HIV can be passed on from mother-to-child during pregnancy, during labor and delivery, and even after during breastfeeding.

Intrapartum and neonatal single-dose nevirapine (sd-NVP) is the foundation of preventing mother-to-child transmission in lower resource settings where it has been used alone or as …


Immunohistochemical Evaluation Of The Effects Of Nebivolol On Intimal Hyperplasia Following Endothelial Injury, İlker Akar, Ali̇ Rahman, M. Cengi̇z Çolak, Bi̇lal Üstündağ, İbrahi̇m Hani̇fi̇ Özercan, Ayhan Uysal Jan 2011

Immunohistochemical Evaluation Of The Effects Of Nebivolol On Intimal Hyperplasia Following Endothelial Injury, İlker Akar, Ali̇ Rahman, M. Cengi̇z Çolak, Bi̇lal Üstündağ, İbrahi̇m Hani̇fi̇ Özercan, Ayhan Uysal

Turkish Journal of Medical Sciences

Intimal hyperplasia is a vascular remodeling process. It is a clinical problem that forms in the vascular wall as a result of smooth muscle cell migration, proliferation, and extracellular matrix accumulation. In this study we examined the immunohistochemical evaluation of the effects of nebivolol on intimal hyperplasia in damaged endothelial tissue. Materials and methods: The study was conducted using 21 rabbits equally divided into 3 groups: control, solvent, and nebivolol. The rabbits in the control group only underwent balloon injury of the abdominal aorta. The rabbits in the solvent group and nebivolol group underwent balloon injury and were treated with …


The Effect Of Spiritualism On The Neuropsychological Function Of Memory, Carla Farcello Jan 2011

The Effect Of Spiritualism On The Neuropsychological Function Of Memory, Carla Farcello

McNair Poster Presentations

The amount of physiological-neurological research performed over the past few years has dramatically increased due to our ability to view the structure and function of the brain in living human beings. The use of imaging tools has resulted in huge strides forward in unlocking some of the mysteries of the 3 pound universe-the human brain. One of the more unique neural processes being recently addressed is the affect of belief and spiritualism-the sense of being connected to something larger than oneself-on the human brain. This study hypothesized that better memory will be documented among the experimental group who report being …


A Pooled Analysis Of The Resistance Patterns Of Escherichia Coli Strains Isolated From Urine Cultures In Turkey: A Comparison Of The Periods 1997-2001 And 2002-2007, Meltem Işikgöz Taşbakan, Hüsnü Pullukçu, Oğuz Reşat Si̇pahi̇, Tansu Yamazhan, Bi̇lgi̇n Arda, Sercan Ulusoy Jan 2011

A Pooled Analysis Of The Resistance Patterns Of Escherichia Coli Strains Isolated From Urine Cultures In Turkey: A Comparison Of The Periods 1997-2001 And 2002-2007, Meltem Işikgöz Taşbakan, Hüsnü Pullukçu, Oğuz Reşat Si̇pahi̇, Tansu Yamazhan, Bi̇lgi̇n Arda, Sercan Ulusoy

Turkish Journal of Medical Sciences

To compare the resistance patterns of Escherichia coli strains reported to be isolated from urine cultures in published medical literature from Turkey in 1997-2001 and 2002-September 2007. Materials and methods: To find the published series, 3 national databases (Ulakbim Turkish Medical Literature database, http://www.turkishmedline.com, http://medline.pleksus.com.tr), and 2 international databases (Pubmed and Science Citation Index (SCI)) were searched. Results: Data for 25,577 E. coli strains were obtained from 53 articles (28 articles from 1997-2001, 25 from 2002-2007). Of these strains 18,106 were isolated from outpatients, whereas 7471 were from inpatients. When the strains isolated from outpatients were evaluated, there was a …


An Efficient Method For Stable Transfection Of Mouse Myogenic C2c12 Cell Line Using A Nonviral Transfection Approach, Mehmet Deni̇z Akyüz, Burcu Hayta, Pervi̇n Ruki̇ye Di̇nçer Jan 2011

An Efficient Method For Stable Transfection Of Mouse Myogenic C2c12 Cell Line Using A Nonviral Transfection Approach, Mehmet Deni̇z Akyüz, Burcu Hayta, Pervi̇n Ruki̇ye Di̇nçer

Turkish Journal of Medical Sciences

To describe in detail the use of the T-REx^{TM} System (a tetracycline-regulated mammalian expression system; Invitrogen) for rapid, easy, and effective generation of stable C2C12 cell clones. Tetracycline-inducible stable cell lines are useful tools to study the function of various genes in different types of mammalian cells. However, the generation of stable cell lines is a time-consuming, technically difficult, and expensive process. Materials and methods: Generation of a stable C2C12 cell line was performed by stable transfection of the cells with the pcDNA6/TR plasmid vector, which contains the tetracycline repressor and the blasticidin drug resistance genes. The establishment of the …


Role Of Calcium-Activated Potassium Channels In Glioblastoma Volume Regulation, Michael Bryan Mcferrin Jan 2011

Role Of Calcium-Activated Potassium Channels In Glioblastoma Volume Regulation, Michael Bryan Mcferrin

All ETDs from UAB

The most common and most malignant gliomas are the Grade IV Glioblastoma Multiforme (GBM), characterized by a highly proliferative tumor mass and extremely invasive phenotype that allows for profuse dispersal of tumor cells throughout the brain. GBM cells must specifically regulate their cell volume to thrive within the edematous tumor mass and infiltrate throughout the tortuous extracellular spaces of the brain. These rapid and directed volume changes are governed by the controlled flux of potassium and chloride ions across the cell membrane, which move osmotically obliged water. The goal of this dissertation was to investigate the role of calcium-activated potassium …


Killer Immunoglobulin-Like Receptors And Human Leukocyte Polymorphisms In Hiv-1 Pathogenesis, Aimee Marie Merino Jan 2011

Killer Immunoglobulin-Like Receptors And Human Leukocyte Polymorphisms In Hiv-1 Pathogenesis, Aimee Marie Merino

All ETDs from UAB

Human leukocyte antigen (HLA) molecules influence the adaptive and innate immune responses through interactions with cytotoxic T lymphocytes and natural killer cells (NK). HLA influence the activation state of NK through direct binding to killer immunoglobulin-like receptors (KIR) and presentation of HLA-derived peptides to NKG2 receptors. Activated NK can kill HIV-infected cells through direct cytolysis and release cytokines that influence other aspects of the immune system. Variations in KIR gene content and allelic variants have been associated with autoimmunity, transplantation success, and infectious diseases such as hepatitis C and HIV/AIDS. We investigated the impact of KIR genes and potential KIR-HLA …


Structural And Mechanistic Studies On Er Upr Sensor Perk And Mitochondrial Translocon Element Tim44, Wenjun Cui Jan 2011

Structural And Mechanistic Studies On Er Upr Sensor Perk And Mitochondrial Translocon Element Tim44, Wenjun Cui

All ETDs from UAB

The unfolded protein response is one mechanism utilized by endoplasmic reticulum (ER) to maintain the homeostasis between ER protein folding machinery and ER proteins. UPR is induced by three ER transmembrane sensors: IRE1, ATF6 and PERK. PKR-like ER kinase (PERK) can sense the ER stress signal through its luminal domain to activate its cytoplasmic kinase domain catalytic activity. PERK kinase domain belongs to the eIF2α family. Members in this family are activated after being autophosphorylated at their activation loops and then specifically phosphorylate eIF2α at its Ser51 position. Phosphorylation of eIF2α can shutdown the cytosol protein translation from the initiation …


Strategies For Combined Screening And Imaging Of Breast Cancer, Jason Morgan Warram Jan 2011

Strategies For Combined Screening And Imaging Of Breast Cancer, Jason Morgan Warram

All ETDs from UAB

Successful treatment of breast cancer directly correlates with tumor stage and grade at diagnosis. Early diagnosis leads to a five-year relative survival rate of 96.8% as opposed to only a 22.5% five-year survival rate when diagnosed at late stage. Cancer-specific mechanisms need to be extended to enable cancer detection in an individual patient, in particular, the metastatic burden that currently cannot be assessed by conventional imaging. This approach for cancer detection would remove the biases of patient characteristics, permit immediate diagnostic feedback, improve sensitivity for early detection of small metastatic lesions, and be cost effective. Toward this goal, the cancer-specific …


Ecology And Transmission Of Eastern Equine Encephalitis Virus In The Southeastern United States, Gregory Scott White Jan 2011

Ecology And Transmission Of Eastern Equine Encephalitis Virus In The Southeastern United States, Gregory Scott White

All ETDs from UAB

The virus Eastern Equine Encephalitis virus (EEEV) is a highly pathogenic arthropod-borne virus (arbovirus) present in the US. The virus is listed as a reportable illness to the Centers of Disease Control and Prevention (CDC) and is also listed as a select agent by Human Health and Services (HHS). Studies on EEEV starting back in the 1930's have determined many important facets of the ecology, transmission and evolution of the virus. It is understood that in many endemic foci, the mosquito Culiseta melanura is the primary enzootic vector of the virus. EEEV is thus maintained in an enzootic cycle between …


The Natural History Of Sivcpz Infection In Wild Living Chimpanzees, Rebecca Steele Rudicell Jan 2011

The Natural History Of Sivcpz Infection In Wild Living Chimpanzees, Rebecca Steele Rudicell

All ETDs from UAB

Simian immunodeficiency virus of chimpanzees (SIVcpz) is the immediate precursor to human immunodeficiency virus type 1 (HIV-1), but even the most basic aspects of SIVcpz infection in its natural host are unknown. Here, we present the first comprehensive analysis of the natural history of SIVcpz infection in wild living chimpanzees. Using non-invasive (feces and urine based) methods, we studied two unique chimpanzee populations in Tanzania: the famous chimpanzees of Gombe National Park and the savanna chimpanzees of Ugalla, located about 135 km southeast of Gombe. Gombe chimpanzees are endemically infected with SIVcpz, and the park's established research infrastructure provides a …


Human Cytosolic Sulfotransferase 2b1b: Structure, Function And Expression In Human Brain, Emily D. Salman Jan 2011

Human Cytosolic Sulfotransferase 2b1b: Structure, Function And Expression In Human Brain, Emily D. Salman

All ETDs from UAB

The human cytosolic sulfotransferases are a family of phase II drug-metabolizing enzymes that conjugate a sulfonate moiety from 3'-phosphoadenosine 5'-phosphosulfate (PAPS) to a hydroxyl moeity on a substrate. SULT2B1b catalyzes the sulfation of hydroxysteroids as well as many xenobiotics; and is expressed extra-hepatically. SULT2B1b is a unique SULT because it has amino (N)- and carboxy (C)-terminal peptide extensions, undergoes post-translational modification, and is localized in both the cytosol and nucleus. Analysis of SULT2B1b revealed that the N- and C-terminal extensions of SULT2B1b are predicted to be intrinsically unstructured peptides. Size exclusion chromatography has revealed that SULT2B1b is enzymatically active as …


In Vivo Analysis Of The Natural Diversity Of The Igr Ires Family And Characterization Of The Role Of Ribosomal Protein S25 In Ires-Mediated Translation, Marla Ilene Hertz Jan 2011

In Vivo Analysis Of The Natural Diversity Of The Igr Ires Family And Characterization Of The Role Of Ribosomal Protein S25 In Ires-Mediated Translation, Marla Ilene Hertz

All ETDs from UAB

Translation of the majority of eukaryotic mRNAs is initiated upon recognition of its 5' cap structure by translation initiation factors in so-called cap-dependent translation. Cap-dependent translation is repressed during cell stress and translation initiation by internal ribosome entry sites (IRESs) predominates. IRESs, located in the 5' untranslated region of specific mRNAs, recruit the ribosome independent of the 5' cap and are essential regulatory elements in many RNA viruses and cellular messages. The dysregulation of cellular IRESs has been linked to cancer because they regulate the expression of genes involved in growth, development and stress response. In comparison to cap-dependent translation, …


Biological Characterization Of Transmitted Human Immunodeficiency Virus Type-1, Tara Grant Edmonds Jan 2011

Biological Characterization Of Transmitted Human Immunodeficiency Virus Type-1, Tara Grant Edmonds

All ETDs from UAB

Heterosexual transmission of human immunodeficiency virus type&ndash1 (HIV&ndash1) accounts for the majority of infections worldwide, with women representing the larger percentage of infected individuals. The events leading to the transmission of HIV&ndash1 at mucosal surfaces are not well defined. Based on the observations that transmitted viruses nearly exclusively utilize the CCR5 coreceptor, and that in 80% of heterosexual transmissions a single virus variant establishes infection, there appears to be a selection mechanism that allows only a subset of viruses to be transmitted. This genetic bottleneck suggests that transmitted viruses may possess specific phenotypic and/or genotypic properties that allow for their …


Molecular Mechanisms Regulating Caenorhabditis Elegans Sperm Migration, Johnathan Wesley Edmonds Jan 2011

Molecular Mechanisms Regulating Caenorhabditis Elegans Sperm Migration, Johnathan Wesley Edmonds

All ETDs from UAB

Fertilization is the process by which male and female gametes join to give rise to a new organism. Union of sperm and ova requires that sperm be able to successfully locate and migrate towards oocytes in the female reproductive tract. By analyzing the in vitro migration of sperm from diverse species and mapping the complex architecture of their female reproductive tracts, we can infer that sperm must respond to directional cues to seek out the mature oocyte. However, the internal fertilization schemes of most complex animals complicate the analysis of in vivo sperm migration. The transparent epidermis of the nematode …


The Role Of Tgf-Ss Receptors In The Induction Of Mucosal Tolerance, Rebekah Sims Gilbert Jan 2011

The Role Of Tgf-Ss Receptors In The Induction Of Mucosal Tolerance, Rebekah Sims Gilbert

All ETDs from UAB

Oral tolerance, defined as the immunologic state of systemic and mucosal unresponsiveness to an antigen, is an essential function of the mucosal immune system. Although antigen presentation has been found to play an important role in oral tolerance, T cells are known to be the effector immune cells that perpetrate this state. Recent studies found that antigen-specific T regulatory (Treg) cells are important in the induction and maintenance of oral tolerance. The extrathymic development of these Tregs depends on the presence of TGF-ß1 during the differentiation process. However, it has also been shown that oral tolerance could be induced in …


The Sodium-Potassium-Chloride Cotransporter In Glioma Biology, Brian R. Haas Jan 2011

The Sodium-Potassium-Chloride Cotransporter In Glioma Biology, Brian R. Haas

All ETDs from UAB

The most common malignant primary brain tumor, gliomas usually derive from glial cells including oligodendrocytes and astrocytes. These tumors are characterized by high rates of proliferation and aberrant migration which make them notoriously difficult to treat using standard treatment paradigms such as chemotherapy and radiation. In order for glioma cells to migrate into the surrounding brain tissue, they must undergo rapid and dynamic volume changes. Previous work published by the Sontheimer laboratory and others indicates glioma utilize the flux of ions across the cell membrane to aid in volume changes associate with cell migration. In this dissertation, I show the …


Structural And Functional Studies On Group A Streptococcal Bacteriophage Hyaluronidase, Joo Hyoung Lee Jan 2011

Structural And Functional Studies On Group A Streptococcal Bacteriophage Hyaluronidase, Joo Hyoung Lee

All ETDs from UAB

Aberrant hyaluronan production is frequently associated with tumors where the elevated levels of tumoral hyaluronan are often associated with higher expression levels of cellular hyaluronidases that produce saturated hyaluronan fragments with divergent pro-tumoral activities. In this thesis, we provide evidence that different hyaluronan metabolism of bacteriophage hyaluronidase (HylP) elicits distinct alteration in breast cancer cell behavior. We demonstrate through comparative analysis with bovine testicular hyaluronidase (BTH) that higher enzyme activity, specificity for hyaluronan and production of unsaturated oligosaccharides render HylP to have profound effects on growth, migration and invasion activities of breast carcinoma cells, whereas BTH and its saturated metabolites …


Role Of Ras Proteins In Malignant Peripheral Nerve Sheath Tumors, Nicole Marie Brossier Jan 2011

Role Of Ras Proteins In Malignant Peripheral Nerve Sheath Tumors, Nicole Marie Brossier

All ETDs from UAB

Malignant peripheral nerve sheath tumors (MPNSTs) arising in patients with neurofibromatosis type I (NF1) are null for the tumor suppressor neurofibromin, a negative regulator of signaling from both classic Ras (H-Ras, N-Ras and K-Ras) and R-Ras (R-Ras, R-Ras2/TC21, M-Ras/R-Ras3) subfamily members. Treatment of these tumors with Ras-targeted agents such as farnesyltransferase inhibitors has proven unsuccessful, likely due to the inability of these agents to successfully target all of the Ras isoforms regulated by neurofibromin. Thus, determining which Ras isoforms are critical for MPNST pathogenesis would be of therapeutic value. In this dissertation, we first review the clinical manifestations of NF1 …


Role Of The Cystine/Glutamate Exchanger In Glioma Cell Biology, Toyin Adeyemi Ogunrinu Jan 2011

Role Of The Cystine/Glutamate Exchanger In Glioma Cell Biology, Toyin Adeyemi Ogunrinu

All ETDs from UAB

Changes in the glioma microenvironment including oxygen (O2) levels, supply of amino acid such as L-glutamate and L-cystine and glutathione (GSH) concentrations play a critical role in glioma biology. Previous data from our laboratory and others have implicated the L-cystine/L-glutamate exchanger, system xc- in the invasion and proliferation of cancers including glioma. The central aim of this dissertation was to characterize the contribution of L-cystine uptake, GSH synthesis and L-glutamate release to migration and proliferation of glioma cells. In my first study, I examined the role of system xc- mediated L-glutamate release on glioma migration. I show that activation of …


Molecular Piracy In The Mobilization Of Staphylococcus Aureus Pathogenicity Island 1, Michael Spilman Jan 2011

Molecular Piracy In The Mobilization Of Staphylococcus Aureus Pathogenicity Island 1, Michael Spilman

All ETDs from UAB

Staphylococcus aureus bacteriophage 80α is a temperate, double-stranded DNA phage that serves as a "helper" phage for the mobilization of several S. aureus pathogenicity islands (SaPIs), including SaPI1. When mobilized by 80α, SaPI1 genomes are packaged into smaller phage-like transducing particles composed of 80α capsid (gp47), scaffolding (gp46) and portal (gp42) proteins. In this dissertation, I utilize electron microscopy and biochemistry to tease apart the structural and genetic controls and consequences of SaPI1 as a molecular pirate. More specifically, I show that two SaPI1 proteins shift assembly from 63-nm, T = 7 icosahedral capsids to 47-nm, T = 4 capsids, …


Calcium Dynamics Of Glial Cells And Genetic Influences On Behavior Of The Nematode Caenorhabditis Elegans, Randy Franklin Stout Jan 2011

Calcium Dynamics Of Glial Cells And Genetic Influences On Behavior Of The Nematode Caenorhabditis Elegans, Randy Franklin Stout

All ETDs from UAB

A major challenge in neuroscience is understanding how the different neural cell types work together to process information and produce a behavioral output. Glial cells of the human brain have long been thought to act as support for the fundamental cell to cell communication at the core of cognition: neuronal synaptic communication. Research over the past several decades measuring glial activity and experimentally controlling glial cells in rodent model systems has shown that the two macroglia sub-types of glial cells (astrocytes and oligodendrocytes) have active roles in establishment, maintenance, and modulation of synaptic communication in the mammalian brain. Much of …


The Intestinal Extracellular Matix As An Innate Regulator Of Effector T-Cell Responses, Kayci Renee Huff Jan 2011

The Intestinal Extracellular Matix As An Innate Regulator Of Effector T-Cell Responses, Kayci Renee Huff

All ETDs from UAB

Extracellular matrix (stroma) regulation of mucosal T-cell function is incompletely understood. Here we uncovered a role for intestinal stromal products in the innate regulation of effector T-cells. Stroma-conditioned media (S-CM) derived from normal human intestinal stroma (TGF-&betahi/IL-6lo/IL-1ßlo) significantly down-regulated T-cell proliferation and IFN-&gamma production compared to S-CM derived from inflamed Crohn's mucosa (TGF-&betahi/IL-6hi/IL-1&betahi). Antibody neutralization studies showed that TGF-&beta in normal S-CM inhibited T-cell proliferation and IFN-&gamma production, whereas IL-6 plus IL-1&beta in Crohn's S-CM promoted T-cell proliferation, and the IL-1&beta alone promoted IFN-γ and IL-17 release. Importantly, stromal cells in normal tissue produce TGF-&beta and contribute to mucosal homeostasis …