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Articles 6121 - 6150 of 8407

Full-Text Articles in Microbiology

Q-Ve-Oph, A Control Caspase Inhibitor For Analyzing Neuronal Death, Rebecca L. Bricker Jan 2012

Q-Ve-Oph, A Control Caspase Inhibitor For Analyzing Neuronal Death, Rebecca L. Bricker

Browse all Theses and Dissertations

Sarin is a neurotoxin that has been used in terrorist attacks in Japan and is a potential bioterrorist weapon. It induces seizures by affecting the regulation of neurotransmitters in the brain. Seizures are directly correlated to neuronal damage. Two types of neuronal damage that can occur are apoptosis and necrosis. One of the main regions of the brain where neuronal death occurs is the hippocampus, which is involved in memory. Victims showed chronic decline of memory loss 3 and 7 years after the Tokyo's terrorist attack incident. There are treatments available that can break down sarin or can block the …


The Effects Of Enteropathogenic And Commensal Escherichia Coli On Tight Junction Permeability, Hilary Kaye Allen Jan 2012

The Effects Of Enteropathogenic And Commensal Escherichia Coli On Tight Junction Permeability, Hilary Kaye Allen

Browse all Theses and Dissertations

The intestinal mucosa maintains a barrier between materials from the external environment and the internal environment of the host. Disruption of the gut wall integrity is involved in the development of various intestinal diseases, such as Irritable Bowel Syndrome (IBS) and Crohn's disease. The intestinal mucosa is lined with epithelial cells that are connected by tight junctions, the intercellular junctions that form a selectively permeable barrier between paracellular pathways. Enteric pathogens, such as enteropathogenic Escherichia coli (EPEC), can disrupt the tight junctions of epithelial cells by altering the cellular cytoskeleton or by directly affecting tight junction proteins. Commensal Escherichia coli …


Mhc Class I Expression In Murine Fibroblast And Keratinocyte Cell Lines During The First Twenty-Four Hours Of Infection With Herpes Simplex Virus-1 (Hsv-1), Prasanthi Kumchala Jan 2012

Mhc Class I Expression In Murine Fibroblast And Keratinocyte Cell Lines During The First Twenty-Four Hours Of Infection With Herpes Simplex Virus-1 (Hsv-1), Prasanthi Kumchala

Browse all Theses and Dissertations

The hypothesis of this study is: HSV-1 infection of murine fibroblasts and keratinocytes inhibits expression of MHC class I molecules during first 24 hours of infection. IFN-γ pretreatment of fibroblasts protected the cells from virus-induced inhibition of MHC class I expression, but did not protect keratinocytes. Herpesviruses are known for their ability to establish persistent infections. Herpesviruses exert many different ways to suppress host defense mechanisms. One such way is by down regulating expression of the major histocompatibility complex I (MHC I) molecules in infected cells. Epidermal cells such as keratinocytes are the major sites for herpes simplex virus type …


The Effects Of Hsv-1 Challenge On Polarized Murine Macrophages: An In Vitro Model Using The J774a.1 Murine Macrophage Cell Line, Adam Craig Reichard Jan 2012

The Effects Of Hsv-1 Challenge On Polarized Murine Macrophages: An In Vitro Model Using The J774a.1 Murine Macrophage Cell Line, Adam Craig Reichard

Browse all Theses and Dissertations

In our current study we examined the effects of HSV-1 challenge on J774A.1 macrophages polarized to either a proinflammatory (M1) or anti-inflammatory (M2) phenotype. Polarized J774A.1 macrophages were characterized using CD14-CD86 and SOCS1-SOCS3 expression levels. SOCS proteins are a family of proteins that are capable of inhibiting cytokine-signaling pathways. HSV-1 up regulates expression of SOCS1 protein levels in infected cells, inhibiting the ability of infected cells to produce proinflammatory products (Nowoslawski Akhtar and Benveniste, 2011). This study shows that signals within the microenvironment play a greater role in macrophage polarization, and SOCS1-SOCS3 expression levels, than does HSV-1 challenge. M1 macrophages …


Suppressor Of Cytokine Signaling (Socs) 1 & 3 Expression In Hsv-1- Infected And Interferon-Γ-Treated Neuro-2a Cells, Melinda Jones Jan 2012

Suppressor Of Cytokine Signaling (Socs) 1 & 3 Expression In Hsv-1- Infected And Interferon-Γ-Treated Neuro-2a Cells, Melinda Jones

Browse all Theses and Dissertations

This study examined the effects of HSV-1 infection and IFN-γ treatment on Neuro-2A cells. HSV-1 induces expression of SOCS1 and SOCS3 in infected cells, inhibiting the ability of these cells to produce the pro inflammatory, antiviral cytokine IFN-γ (Nowoslawski and Benveniste, 2011). SOCS1 and SOCS3 levels were determined in IFN-γ-treated cells, virus-infected cells, and cells that were both IFN-γ-treated and virus-infected. Results were compared with untreated, uninfected control cells. Flow cytometry data analysis showed a slight decrease in SOCS1 and SOCS3 protein levels in cells treated with IFN-γ for 6 hours compared to control cells. A significant decrease in SOCS1 …


The Construction Of A Plasmid For Detecting The Pathway Of Arginine Metabolism In Human Macrophages: A Real-Time Assessment Of Macrophage Polarity, Benjamin A. Holmes Jan 2012

The Construction Of A Plasmid For Detecting The Pathway Of Arginine Metabolism In Human Macrophages: A Real-Time Assessment Of Macrophage Polarity, Benjamin A. Holmes

Browse all Theses and Dissertations

Macrophages are "first responders", innate immune system cells which quickly arrive to a site of infection and injury, consuming cell debris and foreign matter and recruiting other immune system cells to the area. While historically they have been thought to react uniformly to all challenges, the discovery of toll-like receptors has shown that macrophages actually work closely with the adaptive immune system in fine-tuning the immune response. Furthermore, it has recently been discovered that macrophages can become polarized to one of two subtypes-M1 or M2.

M1 macrophages are efficient producers of reactive oxygen species, nitrogen intermediates, and inflammatory cytokines. They …


Efficient And Robust Rna-Seq Process For Cultured Bacteria And Complex Community Transcriptomes, Georgia Giannoukos, Dawn M. Ciulla, Katherine Huang, Brian J. Haas, Jacques Izard, Joshua Z. Levin, Jonathan Livny, Ashlee M. Earl, Dirk Gevers, Doyle V. Ward, Chad Nusbaum, Bruce W. Birren, Andreas Gnirke Jan 2012

Efficient And Robust Rna-Seq Process For Cultured Bacteria And Complex Community Transcriptomes, Georgia Giannoukos, Dawn M. Ciulla, Katherine Huang, Brian J. Haas, Jacques Izard, Joshua Z. Levin, Jonathan Livny, Ashlee M. Earl, Dirk Gevers, Doyle V. Ward, Chad Nusbaum, Bruce W. Birren, Andreas Gnirke

Department of Food Science and Technology: Faculty Publications

We have developed a process for transcriptome analysis of bacterial communities that accommodates both intact and fragmented starting RNA and combines efficient rRNA removal with strand-specific RNA-seq. We applied this approach to an RNA mixture derived from three diverse cultured bacterial species and to RNA isolated from clinical stool samples. The resulting expression profiles were highly reproducible, enriched up to 40-fold for non-rRNA transcripts, and correlated well with profiles representing undepleted total RNA.


Interleukin-6 Control Of Early Theiler’S Murine Encephalomyelitis Virus Replication In Macrophages Occurs In Conjunction With Stat1 Activation And Nitric Oxide Production., Tyler C. Moore, Katherine L. Bush, Deborah M. Brown, Thomas M. Petro Jan 2012

Interleukin-6 Control Of Early Theiler’S Murine Encephalomyelitis Virus Replication In Macrophages Occurs In Conjunction With Stat1 Activation And Nitric Oxide Production., Tyler C. Moore, Katherine L. Bush, Deborah M. Brown, Thomas M. Petro

Nebraska Center for Virology: Faculty Publications

During Theiler’s virus (TMEV) infection of macrophages it is thought that high IL-6 levels contribute to demyelinating disease found in chronically infected SJL/J mice but absent in B10.S mice capable of clearing the infection. Therefore, IL-6 expression was measured in TMEV-susceptible SJL/J and TMEV-resistant B10.S macrophages during their infection with TMEV DA strain or responses to LPS or poly I:C. Unexpectedly, IL-6 production was greater in B10.S macrophages than SJL/J macrophages during the first 24 h after stimulation with TMEV, LPS or poly I:C. Further experiments showed that in B10.S, SJL/J, and RAW264.7 macrophage cells, IL-6 expression was dependent on …


Chloroviruses: Not Your Everyday Plant Virus, James L. Van Etten, David D. Dunigan Jan 2012

Chloroviruses: Not Your Everyday Plant Virus, James L. Van Etten, David D. Dunigan

Nebraska Center for Virology: Faculty Publications

Viruses infecting higher plants are among the smallest viruses known and typically have four to ten protein-encoding genes. By contrast, many viruses that infect algae (classified in the virus family Phycodnaviridae) are among the largest viruses found to date and have up to 600 protein- encoding genes. This brief review focuses on one group of plaque-forming phycodnaviruses that infect unicellular chlorella-like green algae. The prototype chlorovirus PBCV-1 has more than 400 protein-encoding genes and 11 tRNA genes. About 40% of the PBCV-1 encoded proteins resemble proteins of known function including many that are completely unexpected for a virus. In many …


Molecular Genetic And Biochemical Characterization Of The Vaccinia Virus I3 Protein, The Replicative Single-Stranded Dna Binding Protein, Matthew D. Greseth, Kathleen A. Boyle, Matthew S. Bluma, Bethany Unger, Matthew S. Wiebe, Jamaria A. Soares-Martins, Nadi T. Wickramasekera, James Wahlberg, Paula Traktman Jan 2012

Molecular Genetic And Biochemical Characterization Of The Vaccinia Virus I3 Protein, The Replicative Single-Stranded Dna Binding Protein, Matthew D. Greseth, Kathleen A. Boyle, Matthew S. Bluma, Bethany Unger, Matthew S. Wiebe, Jamaria A. Soares-Martins, Nadi T. Wickramasekera, James Wahlberg, Paula Traktman

Nebraska Center for Virology: Faculty Publications

Vaccinia virus, the prototypic poxvirus, efficiently and faithfully replicates its approximately 200-kb DNA genome within the cytoplasm of infected cells. This intracellular localization dictates that vaccinia virus encodes most, if not all, of its own DNA replication machinery. Included in the repertoire of viral replication proteins is the I3 protein, which binds to single-stranded DNA (ssDNA) with great specificity and stability and has been presumed to be the replicative ssDNA binding protein (SSB). We substantiate here that I3 colocalizes with bromodeoxyuridine (BrdU)-labeled nascent viral genomes and that these genomes accumulate in cytoplasmic factories that are delimited by membranes derived from …


Lineage-Specific Differences Between Human And Simian Immunodeficiency Virus Regulation Of Gp120 Trimer Association And Cd4 Binding, Andrés Finzi, Beatriz Pacheco, Shi-Hua Xiang, Marie Pancera, Alon Herschhorn, Liping Wang, Xing Zeng, Anik Desormeaux, Peter D. Kwong, Joseph Sodroski Jan 2012

Lineage-Specific Differences Between Human And Simian Immunodeficiency Virus Regulation Of Gp120 Trimer Association And Cd4 Binding, Andrés Finzi, Beatriz Pacheco, Shi-Hua Xiang, Marie Pancera, Alon Herschhorn, Liping Wang, Xing Zeng, Anik Desormeaux, Peter D. Kwong, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

Metastable conformations of the gp120 and gp41 envelope glycoproteins of human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency virus (SIV) must be maintained in the unliganded state of the envelope glycoprotein trimer. Binding of gp120 to the primary receptor, CD4, triggers the transition to an open conformation of the trimer, promoting interaction with the CCR5 chemokine receptor and ultimately leading to gp41-mediated virus-cell membrane fusion and entry. Topological layers in the gp120 inner domain contribute to gp120-trimer association in the unliganded state and to CD4 binding. Here we describe similarities and differences between HIV-1 and SIVmac gp120. In both …


Subunit Organization Of The Membrane-Bound Hiv-1 Envelope Glycoprotein Trimer, Youdong Mao, Liping Wang, Christopher Gu, Alon Herschhorn, Shi-Hua Xiang, Hillel Haim, Xinzhen Yang, Joseph Sodroski Jan 2012

Subunit Organization Of The Membrane-Bound Hiv-1 Envelope Glycoprotein Trimer, Youdong Mao, Liping Wang, Christopher Gu, Alon Herschhorn, Shi-Hua Xiang, Hillel Haim, Xinzhen Yang, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

The trimeric human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env) spike is a molecular machine that mediates virus entry into host cells and is the sole target for virus-neutralizing antibodies. The mature Env spike results from cleavage of a trimeric gp160 precursor into three gp120 and three gp41 subunits. Here we describe an ~11-Å cryo-EM structure of the trimeric HIV-1 Env precursor in its unliganded state. The three gp120 and three gp41 subunits form a cage-like structure with an interior void surrounding the trimer axis. Interprotomer contacts are limited to the gp41 transmembrane region, the torus-like gp41 ectodomain, and …


Comparative Analysis Of The Fusion Efficiency Elicited By The Envelope Glycoprotein V1–V5 Regions Derived From Human Immunodeficiency Virus Type 1 Transmitted Perinatally, Hongyan Guo, Levon Abrahamyan, Chang Liu, Mackenzie Waltke, Yunqi Geng, Qimin Chen, Charles Wood, Xiaohong Kong Jan 2012

Comparative Analysis Of The Fusion Efficiency Elicited By The Envelope Glycoprotein V1–V5 Regions Derived From Human Immunodeficiency Virus Type 1 Transmitted Perinatally, Hongyan Guo, Levon Abrahamyan, Chang Liu, Mackenzie Waltke, Yunqi Geng, Qimin Chen, Charles Wood, Xiaohong Kong

Nebraska Center for Virology: Faculty Publications

Understanding the properties of viruses preferentially establishing infection during perinatal transmission of human immunodeficiency virus type 1 (HIV-1) is critical for the development of effective measures to prevent transmission. A previous study demonstrated that the newly transmitted viruses (in infants) of chronically infected mother–infant pairs (MIPs) were fitter in terms of growth, which was imparted by their envelope (Env) glycoprotein V1–V5 regions, than those in the corresponding chronically infected mothers. In order to investigate whether the higher fitness of transmitted viruses was conferred by their higher entry efficiency directed by the V1–V5 regions during perinatal transmission, the fusogenicity of Env …


Antibody Responses To Lytic And Latent Human Herpesvirus 8 Antigens Among Hiv-Infected Patients In Central China, Tiejun Zhang, Na He, Yingying Ding, Qingwu Jiang, Charles Wood Jan 2012

Antibody Responses To Lytic And Latent Human Herpesvirus 8 Antigens Among Hiv-Infected Patients In Central China, Tiejun Zhang, Na He, Yingying Ding, Qingwu Jiang, Charles Wood

Nebraska Center for Virology: Faculty Publications

Human herpesvirus 8 (HHV8) is an important opportunistic infection of HIV/AIDS. However, very little is known about antibody seropositivities to HHV8 lytic and latent antigens among HIVinfected patients in China. Therefore, a cross-sectional study was conducted to explore HHV8 serostatus among 316 HIV-infected patients in a rural area of central China. The antibody seropositivity to HHV8 ORF65 (lytic) and LANA (latent) antigens was 12.7% and 10.4%, respectively. Patients who were naïve to antiretroviral therapy (ART) were more likely to be seropositive for antibodies to ORF65 (OR: 3.79; 95% CI: 1.71–8.42) and LANA (OR: 3.77; 95% CI: 1.55–9.14) than patients receiving …


Heme Oxygenase-1 Regulates The Immune Response To Influenza Virus Infection And Vaccination In Aged Mice, Nathan W. Cummins, Eric A. Weaver, Shannon M. May, Anthony J. Croatt, Oded Foreman, Richard B. Kennedy, Gregory A. Polan, Michael A. Barry, Karl A. Nath, Andrew D. Badley Jan 2012

Heme Oxygenase-1 Regulates The Immune Response To Influenza Virus Infection And Vaccination In Aged Mice, Nathan W. Cummins, Eric A. Weaver, Shannon M. May, Anthony J. Croatt, Oded Foreman, Richard B. Kennedy, Gregory A. Polan, Michael A. Barry, Karl A. Nath, Andrew D. Badley

Nebraska Center for Virology: Faculty Publications

Underlying mechanisms of individual variation in severity of influenza infection and response to vaccination are poorly understood. We investigated the effect of reduced heme oxygenase-1 (HO-1) expression on vaccine response and outcome of influenza infection. HO-1-deficient and wild-type (WT) mice (kingdom, Animalia; phylum, Chordata; genus/species, Mus musculus) were infected with influenza virus A/PR/8/34 with or without prior vaccination with an adenoviral-based influenza vaccine. A genome-wide association study evaluated the expression of single-nucleotide polymorphisms (SNPs) in the HO-1 gene and the response to influenza vaccination in healthy humans. HO-1-deficient mice had decreased survival after influenza infection compared to WT mice (median …


Bacterial Community Structure Of Contrasting Soils Underlying Bornean Rain Forests: Inferences From Microarray And Next-Generation Sequencing Methods, Sabrina E. Russo, Ryan Legge, Karrie A. Weber, Eoin L. Brodie, Katherine C. Goldfarb, Andrew K. Benson, Sylvester Tan Jan 2012

Bacterial Community Structure Of Contrasting Soils Underlying Bornean Rain Forests: Inferences From Microarray And Next-Generation Sequencing Methods, Sabrina E. Russo, Ryan Legge, Karrie A. Weber, Eoin L. Brodie, Katherine C. Goldfarb, Andrew K. Benson, Sylvester Tan

School of Biological Sciences: Faculty Publications

Soil microbial diversity is vast, and we lack even basic understanding of how this diversity is distributed ecologically. Using pyrosequencing and microarray methods, we quantified the structure of bacterial communities in two contrasting soils underlying Bornean rain forest (clay and sandy loam) that differ markedly in soil properties, aboveground tree flora, and leaf litter decomposition rates. We found significant soil-related taxonomic and phylogenetic differences between communities that, due to their proximity, are independent of climate. Bacterial communities showed distinct compositional and taxon-abundance distributions that were significantly correlated with the structure of the overlying tree community. Richness of bacteria was greater …


Quorum Sensing Activity In Ophiostoma Ulmi: Effects Of Fusel Oils And Branched Chain Amino Acids On Yeast-Mycelial Dimorphism, A. Berrocal, J. Navarrete, C. Oviedo, K. W. Nickerson Jan 2012

Quorum Sensing Activity In Ophiostoma Ulmi: Effects Of Fusel Oils And Branched Chain Amino Acids On Yeast-Mycelial Dimorphism, A. Berrocal, J. Navarrete, C. Oviedo, K. W. Nickerson

Kenneth Nickerson Papers

Aims: For Ophiostoma (Ceratocystis) ulmi, the ability to undergo morphological change is a crucial factor for its virulence. To gain an understanding of quorum- sensing activity in O. ulmi as it relates to yeast-mycelium dimorphism control, this study examines the effects of branched-chain amino acids as well as their fusel alcohols and fusel acids as quorum sensing molecules.

Methods and Results: In a defined medium containing glucose, proline and salts, O. ulmi grew as yeasts when the culture was inoculated with a high density of spores (2-107 CFU ml-1) and as mycelia when inoculated …


Thoughts On Quorum Sensing And Fungal Dimorphism, Kenneth W. Nickerson, Audrey L. Atkin, Jessica C. Hargarten, Ruvini U. Pathirana, Sahar Hasim Jan 2012

Thoughts On Quorum Sensing And Fungal Dimorphism, Kenneth W. Nickerson, Audrey L. Atkin, Jessica C. Hargarten, Ruvini U. Pathirana, Sahar Hasim

Papers in Microbiology

Farnesol has been best studied for its role in regulating fungal dimorphism. However, farnesol is also a lipid and in this review we analyze data relevant to farnesol’s function and synthesis from the perspective of farnesol and bacterial endotoxins acting as membrane active compounds. This analysis implicates the possible roles of: (1) endotoxins in the regulation of farnesol production by C. albicans; (2) farnesol in the interactions between C. albicans and the host during disseminated infections; and (3) ubiquinones in the mechanisms for unusually high resistance to farnesol by some C. albicans cell types. Finally we discuss the implications …


In Vitro Antimicrobial Effect Of A Cold Plasma Jet Against Enterococcus Faecalis Biofilms, Chunqi Jiang, Christoph Schaudinn, David E. Jaramillo, Paul Webster, J. William Costerton Jan 2012

In Vitro Antimicrobial Effect Of A Cold Plasma Jet Against Enterococcus Faecalis Biofilms, Chunqi Jiang, Christoph Schaudinn, David E. Jaramillo, Paul Webster, J. William Costerton

Bioelectrics Publications

The hypothesis that a cold plasma jet has the antimicrobial effect against Enterococcus faecalis biofilms was tested in vitro. 27 hydroxyapatite discs were incubated with E. faecalis for six days to form a monoculture biofilm on the disc surface. The prepared substrata were divided into three groups: the negative control, the positive control (5.25% NaOCl solution), and the plasma treatment group. Resultant colony-forming unit counts were associated with observations of bacterial cell morphology changes using scanning electron microscopy (SEM). Treatment of E. faecalis biofilm with the plasma and 5.25% NaOCl for 5min resulted in 93.1% and 90.0% kill (P < 0.0001), respectively. SEM detected that nearly no intact bacteria were discernible for the plasmaexposed HA disc surfaces. The demonstrated bactericidal effect of the plasma with direct surface contact may be due to the enhanced oxidation by the locally produced reactive plasma species.


Genomic And Physiological Characterization Of The Verrucomicrobia Isolate Diplosphaera Colitermitum Gen. Nov., Sp. Nov., Reveals Microaerophily And Nitrogen Fixation Genes, John T. Wertz, Eunji Kim, John A. Breznak, Thomas M. Schmidt Jan 2012

Genomic And Physiological Characterization Of The Verrucomicrobia Isolate Diplosphaera Colitermitum Gen. Nov., Sp. Nov., Reveals Microaerophily And Nitrogen Fixation Genes, John T. Wertz, Eunji Kim, John A. Breznak, Thomas M. Schmidt

University Faculty Publications and Creative Works

Previously we reported the cultivation of novel verrucomicrobia, including strain TAV2 (93% 16S rRNA gene identity to its nearest cultivated representative, Opitutus terreae PB90-1) from the gut of the termite Reticulitermes flavipes. To gain better insight into the Verrucomicrobia as a whole and understand the role of verrucomicrobia within the termite gut ecosystem, we analyzed a draft genome and undertook a physiological characterization of TAV2. Strain TAV2 is an autochthonous member of the R. flavipes gut microbiota and groups phylogenetically among diverse Verrucomicrobia from R. flavipes and other termites that are represented by 16S rRNA gene sequences alone. TAV2 is …


The Effect Of Glucose On Transcription At Cpxr- And Ompr-Regulated Promoters, Andrew Charles Cosgrove Jan 2012

The Effect Of Glucose On Transcription At Cpxr- And Ompr-Regulated Promoters, Andrew Charles Cosgrove

Master's Theses

While reversible acetylation of proteins has been well studied in eukaryotes and is now recognized in bacteria, global protein acetylation in bacteria is a recently appreciated phenomenon. Protein acetylation is known to affect almost every aspect of cellular physiology in eukaryotes and there is proteomic evidence that this may also hold true in bacteria. In eukaryotes, lysines are acetylated by acetyltransferases that use acetyl-CoA as the acetyl group source, and de-acetylated by deacetylases. In bacteria, this reversible process uses enzymes homologous to those used by eukaryotes.

Our lab has recently found that acetylation of RNA polymerase (RNAP) can activate transcription …


Characterization Of The Clostridium Difficile Biofilm, Michelle Laning Jan 2012

Characterization Of The Clostridium Difficile Biofilm, Michelle Laning

Master's Theses

Clostridium difficile is a Gram-positive, spore forming bacterium and an opportunistic gastrointestinal pathogen. Clostridium difficile infection (CDI) is a common nosocomial infection. Upon antibiotic treatment, patients can be colonized with C. difficile from ingestion of spores. After colonization, cells produce toxins creating symptoms from diarrhea to pseudomembranous colitis, and many patients develop recurrent infections. Interactions between host epithelium and the bacteria is a critical step in infection, yet the interaction is not well understood. It is not known how C. difficile evades host immune responses. These are important mechanisms to answer in advancing CDI treatment. A biofilm could contribute to …


Understanding The Regulation Of Metabolic Enzyme Acetylation In E. Coli, Arti Walker-Peddakotla Jan 2012

Understanding The Regulation Of Metabolic Enzyme Acetylation In E. Coli, Arti Walker-Peddakotla

Master's Theses

Global protein acetylation is a newly discovered phenomenon in bacteria. Of the more than 250 acetylations reported in E. coli, many are of metabolic enzymes. Thus, acetylation could represent a novel posttranslational mechanism of metabolic control. Yet, almost nothing is known about the regulation of these acetylations or of their metabolic outcomes. Here, we report that the cAMP receptor protein (CRP) regulates protein acetylation in E. coli and provide evidence that protein acetylation modulates the flux of carbon through central metabolism. When we grew cells in mixed amino acids supplemented with glucose and cAMP, global protein acetylation increased in a …


Evaluation Of Elevated Alanine Aminotransferase And Hepatitis B Virus Dna In Healthy Seronegative Blood Donors, Natasha Ali, Bushra Moiz, Tariq Moatter Jan 2012

Evaluation Of Elevated Alanine Aminotransferase And Hepatitis B Virus Dna In Healthy Seronegative Blood Donors, Natasha Ali, Bushra Moiz, Tariq Moatter

Department of Pathology and Laboratory Medicine

Background: Serum alanine transaminase (ALT) has been used as a surrogate marker for detection of hepatitis B and C in blood donors in Pakistan since 1985. Since the introduction of more sensitive assays the value of ALT became questionable but it was still used with subsequent wastage of blood units with raised ALT.
Finding: We conducted a study for a period of one year to evaluate the usefulness of ALT. During the study period, 25117 subjects donated blood. Eight hundred and seventy two donors (3.4%) were positive for one or more serological tests. ALT of all donors ranged from …


High Isoniazid Resistance Rates In Rifampicin Susceptible Mycobacterium Tuberculosis Pulmonary Isolates From Pakistan, Naima Fasih, Yasraba Rafiq, Kausar Jabeen, Rumina Hasan Jan 2012

High Isoniazid Resistance Rates In Rifampicin Susceptible Mycobacterium Tuberculosis Pulmonary Isolates From Pakistan, Naima Fasih, Yasraba Rafiq, Kausar Jabeen, Rumina Hasan

Department of Pathology and Laboratory Medicine

Background:
Rapid new diagnostic methods (including Xpert MTB/RIF assay) use rifampicin resistance as a surrogate marker for multidrug resistant tuberculosis. Patients infected with rifampicin susceptible strains are prescribed first line anti-tuberculosis therapy. The roll out of such methods raises a concern that strains with resistance to other first line anti-tuberculosis drugs including isoniazid will be missed and inappropriate treatment given. To evaluate implications of using such methods review of resistance data from high burden settings such as ours is essential.
Objective:
To determine resistance to first line anti-tuberculosis drugs amongst rifampicin susceptible pulmonary Mycobacterium tuberculosis (MTB) isolates from Pakistan.
Material …


Neonatal Hyperbilirubinemia In Infants With G6pd C563c > T Variant, Bushra Moiz, Amna Nasir, Sarosh Ahmed Khan, Saleema Amin Kherani, Maqbool Qadir Jan 2012

Neonatal Hyperbilirubinemia In Infants With G6pd C563c > T Variant, Bushra Moiz, Amna Nasir, Sarosh Ahmed Khan, Saleema Amin Kherani, Maqbool Qadir

Department of Pathology and Laboratory Medicine

Background: There is a strong correlation between glucose-6-phosphate dehydrogenase (G6PD) deficiency and neonatal hyperbilirubinemia with a rare but potential threat of devastating acute bilirubin encephalopathy. G6PD deficiency was observed in 4–14% of hospitalized icteric neonates in Pakistan. G6PD c.563C > T is the most frequently reported variant in this population. The present study was aimed at evaluating the time to onset of hyperbilirubinemia and the postnatal bilirubin trajectory in infants having G6PD c.563C > T.
Methods: This was a case–control study conducted at The Aga Khan University, Pakistan during the year 2008. We studied 216 icteric male neonates who were re-admitted for …


Outcome Of Match Related Allogeneic Stem Cell Transplantation Procedures Performed From 2004 Till 2011, Natasha Ali, Salman Naseem Adil, Mohammad Usman Shaikh, Munira Moosajee, Nehal Masood Jan 2012

Outcome Of Match Related Allogeneic Stem Cell Transplantation Procedures Performed From 2004 Till 2011, Natasha Ali, Salman Naseem Adil, Mohammad Usman Shaikh, Munira Moosajee, Nehal Masood

Department of Pathology and Laboratory Medicine

We present our initial experience of allogeneic stem cell transplant procedure performed between April 2004 and August 2011 for various haematological disorders. All patients with non-malignant and malignant haematological disorders with HLA matched donors were selected after pre-transplant workup. Ninety seven patients underwent the procedure. Most common indications for transplant were aplastic anaemia in n=34 (35%), followed by beta-Thalassemia major in n=21 (21.6%) and chronic myeloid leukemia in n=11 patients (11.3%). Primary graft failure present was present in 2.06%. Incidence of graft versus host disease (GvHD) in our patients was 34%. After median follow-up of five years the overall survival …


Characterization Of The Lone Extracytoplasmic Function Sigma Factor, Ós, And Its Role In The Staphylococcus Aureus Virulence And Stress Responses, Halie Kay Miller Jan 2012

Characterization Of The Lone Extracytoplasmic Function Sigma Factor, Ós, And Its Role In The Staphylococcus Aureus Virulence And Stress Responses, Halie Kay Miller

USF Tampa Graduate Theses and Dissertations

Previously our laboratory had identified a novel component of the Staphylococcus aureus regulatory network, an extracytoplasmic function ó factor, óS, involved in stress response and disease causation. Here we present additional characterization of óS, demonstrating a role for it in protection against DNA damage, cell wall disruption and interaction with components of the innate immune system. Promoter mapping reveals the existence of four unique sigS start sites, one of which appears to be subject to auto-regulation. Transcriptional profiling revealed that sigS expression remains low in a number of S. aureus wild-types, but is upregulated in the highly mutated strain RN4220. …


Investigation Of Reservoirs Of Fecal Indicator Bacteria And Water Quality On The Presence Of Allochthonous Pathogens And The Ecology And Virulence Of Vibrio Vulnificus, Christopher Staley Jan 2012

Investigation Of Reservoirs Of Fecal Indicator Bacteria And Water Quality On The Presence Of Allochthonous Pathogens And The Ecology And Virulence Of Vibrio Vulnificus, Christopher Staley

USF Tampa Graduate Theses and Dissertations

The quality of recreational and shellfishing waters has historically been monitored using commensal, allochthonous bacteria shed in feces (fecal indicator bacteria, FIB). The fate of FIB in the environment should mimic that of bacterial, protozoan, and viral human pathogens, which may also be allochthonous (e.g. Salmonella, Cryptosporidium, or enteric viruses) or autochthonous (e.g. Vibrio spp.) to aquatic environments. FIB are contributed to water from human and animal sources; however, pollution source cannot be determined by conventional FIB measurements. Because fecal source determination is important for pollution remediation and assessment of human health risks, microbial source tracking (MST) methods are …


Therapeutic Peptide-Based Vaccination Strategies Against Hpv-Induced Cancers, Kelly Barrios Marrugo Jan 2012

Therapeutic Peptide-Based Vaccination Strategies Against Hpv-Induced Cancers, Kelly Barrios Marrugo

USF Tampa Graduate Theses and Dissertations

There is an urgent need for the development of an effective therapeutic vaccine against cancer caused by human papilloma virus (HPV). We focused on HPV-induced malignancies because of their high worldwide prevalence (e.g., cervical carcinoma and head & neck cancer). A successful therapeutic vaccine could prevent the 250 000 deaths/year worldwide and the 2.25 billion dollars that

are expended in related care in the US.

We used an HPV-induced mouse cancer model to test vaccines

composed of a CD8 T cell peptide epitope administered with potent adjuvants designed to generate vast numbers of high avidity cytotoxic T lymphocytes specific for …