Microbiology Commons^™

Virus Purification, Detection And Removal, Khrupa Saagar Vijayaragavan

Dissertations, Master's Theses and Master's Reports - Open

The biopharmaceutical industry has a growing demand and an increasing need to improve the current virus purification technologies, especially as more and more vaccines are produced from cell-culture derived virus particles. Downstream purification strategies can be expensive and account for 70% of the overall manufacturing costs. The economic pressure and purification processes can be particularly challenging when the virus to be purified is small, as in our model virus, porcine parvovirus (PPV). Our efforts are focused on designing an easy, economical, scalable and efficient system for virus purification, and we focused on aqueous two-phase systems. Industry acceptable standards for virus …

Role Of The Pkna And Pknb Kinases In Mycobacterium Tuberculosis, Tripti Anandan

Wayne State University Dissertations

To respond to environmental changes, M. tuberculosis possesses eleven "eukaryotic-type" Ser/Thr protein kinases. The aim of the study described in this dissertation was to identify role of two of these kinases; PknA and PknB that are essential in M. tuberculosis. Two approaches are described to screen for potential in vivo substrates of PknA/PknB. First approach is based on proteomic search by over-expressing PknA/PknB in M. tuberculosis. Proteomic search led to identification of proteasome to be a substrate of PknA and PknB in M. tuberculosis. Furthermore, I demonstrate that the phosphorylation of PrcA and PrcB by PknA regulates processing of Pre-PrcB. …

The Mechanism For Inhibition Of Vibrio Cholerae Virulence Gene Expression By Bile And Its Fatty Acid Components, Sarah Plecha

Wayne State University Dissertations

Vibrio cholerae is responsible for the diarrheal disease cholera by producing two major virulence factors: cholera toxin (CT) and toxin-coregulated pilus (TCP). During infection, V. cholerae downregulates its motility genes, which are actively expressed in the environment, and upregulates its virulence genes, which are inactive in the environment. Virulence gene transcription is regulated by the major transcriptional activator, ToxT. ToxT is regulated, in part, by host signals, which in turn, make ToxT active or inactive in respect to virulence gene expression. Host signals include temperature and pH as well as the chemical molecules bicarbonate and bile, which are positive and …

Cell Envelope Modifications By Lcp Family Proteins Of Group B Streptococcus And Virulence Singaling By Peptides Of The Salivaricin Locus Of Streptococcus Pyogenes, Hannah Morrison Rowe

Wayne State University Dissertations

ABSTRACT

CELL ENVELOPE MODIFICATIONS BY LCP FAMILY PROTEINS OF GROUP B STREPTOCOCCUS AND VIRULENCE SIGNALING BY PEPTIDES OF THE SALIVARICIN LOCUS OF STREPTOCOCCUS PYOGENES

by

HANNAH MORRISON ROWE

December 2014

Advisor: Dr. Melody Neely

Major: Immunology and Microbiology

Degree: Doctor of Philosophy

Streptococci are important human and animal pathogens. Group B Streptococcus (GBS) is a zoonotic pathogen that is the leading cause of human neonatal sepsis and meningitis. In order to cause systemic disease GBS must produce a polysaccharide capsule. Capsule expression is controlled in part by the protein CpsA. We demonstrate that deletion of the cpsA gene, or expression …

Detection, Identification And Characterization Of The Novel Campylobacter Species: Campylobacter Ureolyticus And Campylobacter Corcagiensis From Their Reservoirs., Monika Koziel

Theses

Campylobacter ureolyticus has been identified in a large proportion of diarrhoeal samples from patients in Ireland. However, the source of human infections has not been established and little is currently known about the potential reservoirs of C. ureolyticus in nature.

The aim of this project was to investigate a range of environmental and animal samples for the presence of this emerging pathogen using a molecular approach, to support the hypothesis of its zoonotic origin.

During the study, C. ureolyticus was detected in 30 out of 1,254 (2.4%) human diarrheic samples and isolated from 11 patients, describing, to the best of …

Gastroenteritis Viruses In Ireland: Epidemiology And Evolution, Lynda Gunn

Theses

Viral gastroenteritis is a common disease of both humans and animals. This thesis focuses on the use of classical virology, coupled with phylogenetics to study gastroenteritis viruses [Bocavirus (BoV), Coronavirus (CoV), and Rotavirus A (RVA)], isolated from selected samples from humans and animals. RVA was associated with outbreaks in elderly care facilities in Northern Ireland, isolates were genotyped and we reported the first detection of G2 lineage lie RVA in Ireland, with other common human RVA genotypes G1P[8], G2P[4] and G9P[8]. Evolutionary dynamics of human RVA VP7 genotypes was examined using codon models of evolution, results show heterogeneous selective pressure …

Socs1/Socs3 Expression And Virus Replication Of Denv2 And Hsv-1 In Cytokine-Polarized Subsets Of Raw 264.7 Macrophages, Nagarjuna Reddy Cheemarla

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Cytokine activation of macrophages leads to "macrophage polarizatio" The M1 subset is polarized by exposure to lipopolysaccharide (LPS) and interferon-gamma (IFN-γ) and M2 polarized cells develop after exposure to interleukin-4 (IL-4) or IL-13. In this study, the RAW 264.7 murine macrophage cell line was used to study the effect herpes simplex virus-Type I (HSV-1) and Dengue virus serotype-2 (DENV2) infections have on cultures of unpolarized (M0) or polarized subsets. The macrophage subsets were characterized using cluster of differentiation markers CD14 and CD86. Uninfected M1 macrophages showed up regulation in expression of the co-stimulatory factor B7.2 (CD86) compared to expression by …

Development Of A Co-Culture System To Mimic The Transfection Of Hsv-1 From Keratinocytes To Neuronal Cells, David A. Dixon

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To more closely mimic the in vivo progression of HSV-1 a novel in vitro method was created. In this study HEL-30 keratinocytes were infected with a 0.1 MOI of HSV-1 and plated unto a membrane with 8μm diameter pores. The membrane insert was then placed into culture wells that contained Neuro-2a cells (N2A). The neurites from the neuronal cells made cell-to-cell contact with the infected HEL-30 cells and the virus was transmitted into the neuronal cells. To determine if infection occurred in the N2A cells the cells were lysed and the lysate incubated with Vero cells to titrate virus plaque …

White Blood Cell Counts, Parasite Prevalence, And Plasma Cortisol Levels Of Dogs In A County Animal Shelter: Changes Over Days And Impact Of A Program Of Repeated Human Interaction, Emily S. Dudley

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Animal shelter housing is highly stressful for a dog, compromising welfare and leading to undesirable behaviors and unknown health consequences. We documented the changes in circulating numbers of white blood cells, plasma cortisol, and fecal parasite shedding of dogs housed for 10 days at a county animal shelter. White blood cell changes were most prominent on Day 10 after arrival to the shelter. Changes included increased total leukocytes, mature neutrophils, and lymphocytes, with less consistent increases in monocytes and neutrophil to lymphocyte ratio (N:L). Fecal parasite shedding was elevated and not affected by day. Cortisol levels of shelter dogs declined …

Identification Of The Sites Of Action Of Inhibitors Of Mammalian Phospholipase D2 (Pld2) And The Role Of Interacting Protein Partners, Ramya Ganesan

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Phospholipase D (PLD) is a key enzyme for the remodeling of phospholipids in the cell membrane. PLD has been implicated in many physiological functions such as chemotaxis and phagocytosis as well as pathological functions such as ischemia/reperfusion and cancer metastasis. Several small molecule inhibitors of PLD have been recently developed to overcome these pathological effects. We have concentrated on 5-Fluoro-2-Indolyl des-Chlorohalopemide (FIPI) which is an indole derivative of halopemide that inhibits the two mammalian isoforms PLD1 and PLD2. We also concentrate on N-[2-[1-(3-Fluorophenyl)-4-oxo-1,3,-8-triazaspiro[4.5]dec-8-yl]ethyl]-2-naphthalenecarboxamide (NFOT) and N-[2-(4-oxo-1-phenyl-1,3,8-triazaspiro[4,5]dec-8-yl)ethyl]-2-naphthalenecarboxamide (NOPT) that are specific inhibitors of the PLD2 isoform. In spite of knowing their …

Comparison Between Flow Cytometry And Bead Method In Counting Cd4 And Cd8 T Lymphocytes In Mouse Spleen Cells Suspension, Abdulrahman Abdalla Allabidi

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The flow cytometry is gold standard method to count CD4, CD8 human T lymphocytes, and calculate CD8 to CD4 ratio in HIV patients peripheral blood to stage them and monitor their response to treatment. In this study, a comparison was made by counting CD4and CD8 mouse spleen T lymphocytes by flow cytometry, and a method involving antibody coated latex beads. The bead method yielded results comparable to those obtained by flow cytometry. These results indicate that antibody coated beads are suitable to determine CD4 and CD8 + T lymphocytes counts in situation where flow cytometry is not readily available.

Effect Of Herpes Simplex Virus-1 On Macrophage Cd Marker Expression, Hind Obaid Albeshri

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Macrophages are specialized phagocytic cells derived from the peripheral blood mononuclear cells. Macrophages can assume M1 or M2 cellular states upon activation with specific cytokines. Upon activation, macrophages produce either pro- or anti- inflammatory cytokines and thereby perform their functions of antigen engulfment and debris clearance. Macrophages have several cell surface cluster differentiation (CD) markers including CD80, CD163 and CD200R that differentiate M1 macrophages from M2. Downstream signaling and cytokine production varies based on the interaction between the specific CD marker and antigen.

The present study was aimed at analyzing and comparing the effects of HSV-1 infection on un-polarized and …

Elucidating The Effects Of Tcdd On The Polymorphic Human Hs1,2 Enhancer, Abdullah Freiwan

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2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a potent environmental toxin known to inhibit immunoglobulin (Ig) gene expression in various animal studies. We have identified the mouse 3'Ig heavy chain regulatory region (3'IgH RR) as a sensitive transcriptional target of TCDD, which may mediate the inhibitory effect of TCDD on Ig expression. Interestingly, the human hs1,2 enhancer is polymorphic and has been associated with a number of autoimmune diseases.

Suggesting a species difference, TCDD inhibited mouse hs1,2 enhancer activation and activated basal human hs1,2 (hs-hs1,2) enhancer activity in the mouse B-cell line. The objective of this study was to elucidate the effects of TCDD …

Adeno-Associated Virus (Aav) Transduction Of Primary Human Cd4+T Lymphocytes, Sahar Hussein Kamel

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Development of latent HIV-infected CD4+ T lymphocytes is the major cause of HIV treatment failure. Adeno-associated virus (AAV) is an attractive vector for anti-HIV gene therapy due to its lack of pathogenicity, low immunogenicity, and persistent transgene expression. However, a major limitation for AAV gene transfer is the cell-specific tropism of each serotype. Only AAV serotypes 2 and 5 have been investigated in hematopoietic cells, both of these serotypes have shown low transduction efficiency. Since each of the currently described AAV serotypes demonstrate distinct tissue tropism, I hypothesized that other serotypes such as AAV1, 4, 8, or 9 may demonstrate …

Expression Of The Alpha, Beta, And Gamma Subunits Of The Interleukin-2 Receptor By Human Vascular Smooth Muscle Cells, Sultan Mohammed Alhayyani

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Interleukin 2 (IL-2) is a member of the cytokine family and contributes to the proliferation, survival, and death of lymphocytes [1]. The interleukin-2 receptor (IL-2) is a tripartite receptor commonly expressed on the surfaces of many lymphoid cells and is composed of three non-covalently associated subunits, alpha (CD25), beta (CD122), and gamma (CD132) [2]. Our laboratory has previously described IL-2 receptor Beta expression by vasculature smooth muscle cells (VSMC) in mice and humans [3]. The current work expands our previous observations by assessing the expression of the alpha and gamma subunits of the IL-2R by VSMCs. Analysis of IL-2R expression …

Live Siv Vaccine Correlate Of Protection: Immune Complex-Inhibitory Fc Receptor Interactions That Reduce Target Cell Availability, Anthony J. Smith, Stephen W. Wietgrefe, Liang Shang, Cavan S. Reilly, Peter J. Southern, Katherine E. Perkey, Lijie Duan, Heinz Kohler, Sybille Muller, James Robinson, John V. Carlis, Qingsheng Li, R. Paul Johnson, Ashley T. Haase

Nebraska Center for Virology: Faculty Publications

Principles to guide design of an effective vaccine against HIV are greatly needed, particularly to

protect women in the pandemic’s epicentre in Africa. We have been seeking these principles by

identifying correlates of the robust protection associated with SIV_mac239Δnef vaccination in the

SIV-rhesus macaque animal model of HIV-1 transmission to women. We have identified one

correlate of SIV_mac239Δnef protection against vaginal challenge as a resident mucosal system for

SIV-gp41 trimer antibody production and neonatal Fc receptor (FcRn)-mediated concentration of

these antibodies on the path of virus entry to inhibit establishment of infected founder populations

at the …

Tick-Bourne Pathogens Of Potential Zoonotic Importance In The Southern African Region, Simbarashe Chitanga, Holly Gaff, Samson Mukaratirwa

Biological Sciences Faculty Publications

The aim of this communication is to provide preliminary information on the tick-borne pathogens of potential zoonotic importance present in southern Africa, mainly focusing on their geographical distribution and host range, and to identify research gaps. The following tick-borne zoonoses have been reported to occur in southern Africa based mainly on case reports: Crimean–Congo haemorrhagic fever caused by Crimean–Congo haemorrhagic fever virus; ehrlichiosis caused by Ehrlichia ruminantium, Ehrlichia canis and Anaplasma phagocytophilum; babesiosis caused by Babesia microti; relapsing fever caused by Borrelia duttonii and rickettsioses caused by Rickettsia africae, Rickettsia aeschlimannii and Rickettsia conorii. The …

Soil Microbial Community Distributions And Disease Suppressiveness In The Coastal Plain Of Georgia, Michael J. Sabula

College of Graduate Studies: Theses & Dissertations

This study compared the soil microbial communities of three vegetation types in the coastal plain of Georgia: 1. crop land actively in use for agricultural production, 2. transitional grassland in early stages of secondary succession, and 3. pristine unmanaged forest land. Microbial species diversity and quantities of microbial DNA were determined from each of these vegetation types at three separate locations near Statesboro, Georgia. Length heterogeneity PCR(LH-PCR) methods and subsequent analysis of fungal, bacterial, and metazoan communities by analysis of similarity (ANOSIM) revealed high within-group similarity by vegetation type, indicating land management intensity and vegetation cover is a strong determining …

Characterization Of The Effects Of Iron On Neisseria Gonorrhoeae Surface Protein Modulation And Host Cell Interactions, Aminat Oki

Theses and Dissertations

Iron is an essential nutrient that is sequestered by iron-binding proteins in the human host resulting in a hostile environment for microbes. Neisseria gonorrhoeae, however, can utilize numerous iron-binding proteins such as transferrin and lactoferrin to acquire this nutrient. During initial infection, gonococci have access to transferrin and lactoferrin present in semen and vaginal fluids, as well as to hemoglobin present in blood during menses or disseminated infections. Consequently, the gonococcus likely encounters conditions of high iron at some stages in the course of natural infection. Potential contributions of iron to gonococcal invasion have however been largely over looked in …

Ovarian Sex Cord Stromal Tumours In Children And Young Girls - A More Than Two Decade Clinicopathological Experience In A Developing Country, Pakistan, Saroona Haroon, Romana Idrees, Aleena Zia, Aisha Memon, Saira Fatima, Naila Kayani

Department of Pathology and Laboratory Medicine

Background: Ovarian sex-cord stromal tumours (SCST) are rare, and relatively infrequent in children. These have to be distinguished from more common germ cell tumors in children and also from benign epithelial neoplasms.
Objectives: The purpose of our study was to report the clinical and pathological findings in young patients with these tumours in our population.
Material and Methods: The present observational cross-sectional study included all subjects SCST, in Aga Khan University Hospital Histopathology Laboratory, Karachi, Pakistan, from January 1992 till July 2013.
Results: Of the total of 513 SCSTs presented during the study period, 39 fulfilled inclusion criteria and were …