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T-Cell Responses To The M3 Immune Evasion Protein Of Murid Gammaherpesvirus 68 Are Partially Protective And Induced With Lytic Antigen Kinetics, Joshua J. Obar, Douglas C. Donovan, Sarah G. Crist, Ondine Silvia, James P. Stewart, Edward J. Usherwood

Dartmouth Scholarship

DNA vaccination with the M3 gene, encoding an immune evasion molecule expressed during both the acute lytic and persistent phases of murid gammaherpesvirus 68 infection, yielded a significantly lower titer of virus in the lung than controls. The protection seen was dependent on T cells, and we mapped an epitope recognized by CD8 T cells. The immune response to this epitope follows the same kinetics as lytic cycle antigens, despite the fact that this gene is expressed in both lytic and persistent stages of infection. This has important implications for our understanding of T-cell responses to putative latency-associated gammaherpesvirus proteins …

Involvement Of Raft-Like Plasma Membrane Domains Of Entamoeba Histolytica In Pinocytosis And Adhesion, Richard C. Laughlin, Glen C. Mcgugan, Rhonda R. Powell, Brenda H. Welter, Lesly A. Temesvari

Publications

Lipid rafts are highly ordered, cholesterol-rich, and detergent-resistant microdomains found in the plasma membrane of many eukaryotic cells. These domains play important roles in endocytosis, secretion, and adhesion in a variety of cell types. The parasitic protozoan Entamoeba histolytica, the causative agent of amoebic dysentery, was determined to have raft-like plasma membrane domains by use of fluorescent lipid analogs that specifically partition into raft and nonraft regions of the membrane. Disruption of raft-like membrane domains in Entamoeba with the cholesterol-binding agents filipin and methyl-β-cyclodextrin resulted in the inhibition of several important virulence functions, fluid-phase pinocytosis, and adhesion to host …

Impact Of Antibiotic Usage On Resistance In Microorganisms; Urinary Tract Infections With E-Coli As A Case In Point, N Sabir, Erum Khan, L Sheikh, Rumina Hasan

Department of Pathology and Laboratory Medicine

Objectives:
In this study, we sought to establish a correlation between consumption of flouoroquinolones in our hospital and the emergence of ofloxacin resistant strains of E. coli in the urinary specimens. Data of all urinary samples, received at Aga Khan University Hospital between January 1995 and December 2002, was retrieved and analyzed. Specimens yielding E-coli as an isolate were included in this study.
Methods:
E. coli Isolates showing >103 colonies were identified using standard microbiological techniques. Antibiotic susceptibility of E. coli was tested using Kirby Bauer disc diffusion method. Antimicrobial usage data, obtained through hospital Pharmacy as unit utilized per …

Distribution Of Kaposi Sarcoma–Associated Herpesvirus/Human Herpesvirus 8 In Maternal Saliva And Breast Milk In Zambia: Implications For Transmission, Brad P. Brayfield, Chipepo Kankasa, John T. West, Jubra Muyanga, Ganapati Bhat, Winslow Klaskala, Charles D. Mitchell, Charles Wood

Nebraska Center for Virology: Faculty Publications

Background. The seroprevalence of Kaposi sarcoma–associated herpesvirus (KSHV)/human herpesvirus 8 (HHV-8) in sub-Saharan Africa suggests that multiple routes of transmission exist. In the present study,we examined 2 possible routes of mother-to-child transmission, through breast milk and saliva, during the first 6 months after delivery. Methods. The prevalence of HHV-8 DNA in the breast-milk cells (n=75), milk supernatant (n=56), colostrum (n=2), and saliva cells (n=65) of HHV-8–seropositive mothers who recently gave birth was examined. Polymerase chain reaction analysis was performed for the detection of HHV-8 in cross-sectional samples isolated at 2, 4, and 6 months after delivery.

Results. None of the …

Evaluation Of Frequency Of Isolation And Trends In Antibiotic Resistance Among Campylobacter Isolates Over 11 Year Period, N G. Ibrahim, Afia Zafar, Rumina Hasan

Department of Pathology and Laboratory Medicine

Objective:
To analyze frequency of isolation and trends in antibiotic resistance among Campylobacter isolates over 11 year period in Microbiology Laboratory, Aga Khan University from the year 1992-2002.
Methods:
Total 52,777 stool specimens were processed during the study period. Enteric pathogens isolated from 8,483 stool samples were further analyzed for frequency of isolation and antimicrobial resistance. Statistical Analysis was done by using descriptive statistics of SPSS version 10. Values were expressed as percentages, mean and rates.
Results:
Campylobacter species were third in frequency of isolation with an isolation rate of 24.8%. C. jejuni was the predominant pathogen followed by C.coli. …

Multiple Signal Transducers And Activators Of Transcription Are Induced By Ebv Lmp-1, Luwen Zhang, Ke Hong, Jun Zhang, Joseph S. Pagano

Nebraska Center for Virology: Faculty Publications

Epstein-Barr virus (EBV) latent membrane protein 1 (LMP-1) is required for EBV immortalization of primary B cells in vitro. Signal transducers and activators of transcription (STATs) play a pivotal role in the initiation and maintenance of certain cancers. STAT proteins, especially STAT-1, -3, and -5, are persistently tyrosine phosphorylated or activated in many cancers. We show here that EBV-infected type III latency cells, in which the EBV oncoprotein, LMP-1 is expressed, express high levels of four STATs (STAT-1, -2, -3, and -5A) and that LMP-1 is responsible for the induction of three (STAT-1, -2, and -3). In addition, the C-terminal …

Methods For Detection Of Salmonella Spp., Parichaya Attaphongse

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Worldwide concern about food safety and associated health costs is increasing, and Salmonella contamination of foods is one of the most important causes of foodborne disease outbreaks. Although conventional detection methods for Salmonella offer high sensitivity and low cost, they require many different steps and are very time consuming. Ideally, methods to detect Salmonella in foods should be rapid, provide high specificity and sensitivity, be cost-effective, and low labor-intensive. Many rapid tests have been developed to address these goals, including DNA-based tests such as nucleic acid hybridization and PCR, immunoassay-based tests such as ELISA, ELF A and immunomagnetic method, and …

The Biological Burden Of Antibiotic Resistance In Staphylococcus Aureus, Natasha Samantha Dean

Loma Linda University Electronic Theses, Dissertations & Projects

Antibiotic resistance is a major problem. Resistance is often mediated by genes on bacterial plasmids and dissemination of resistance is commonly achieved by plasmid transfer. The mechanisms of resistance that are presently understood suggest that resistance is energetically costly. If this is generally true, resistance would reduce the fitness of cells in the absence of antibiotics. We examined the hypothesis that resistance reduces the fitness of microorganism and requires continuous selection to be maintained. To test this hypothesis, we measured the effects of plasmid-borne resistance genes on cell growth by comparing the growth rates of Staphylococcus aureus with and without …

Phylogenetic Analyses Of Texas Isolates Indicate An Evolving Subtype Of The Clade B Feline Immunodeficiency Viruses, Eric A. Weaver, Ellen W. Collisson, Margaret Slater, Guan Zhu

Nebraska Center for Virology: Faculty Publications

Rigorous phylogenetic analyses were used to compare the nucleotide sequences of feline immunodeficiency virus strains isolated from Texas and throughout the world. The envelope V3-V4 sequences and capsid gene of the Texas isolates formed a cluster between subtypes B and E. Statistical comparisons with other published sequences confirmed that the Texas group is a unique cluster, possibly a new subtype, arising from subtype B.

Feline immunodeficiency virus (FIV) was initially isolated in 1987 from a cat in California with severe immunodeficiency and has been recognized as a common worldwide feline pathogen (11, 14, 19, 20, 33). FIV-infected cats exhibit a …

Evaluation Of The Host Range Of Polyvalent Staphylococcal Bacteriophages To Control Mrsa (Staphylococcus Aureus) From Irish Hospitals, Mohamed Farag M. Elbreki

Theses

This study describes firstly, the assembly of a collection of a varied spectrum of staphylococci which can be used to test the efficacy of bacteriophages for the biocontrol of problematic members of this genus. The collection assembled includes a variety of multi-antibiotic resistant MRSA (methicillin resistant S. aureus) strains, hVRSA (hetero vancomycin resistant S. aureus), VRSA and also teicoplenin resistant isolates. It also included a broad range of species of coagulase-negative {non-aureus) staphylococci including S. caprea, S. haemolyticus, S. saprophyticus, S. epidermidis, S. chromogenes, S. capitis, S. hominins and S. hyicus. All strains were characterized by morphology on Baird Parker, …

Ultrastructure Of Mycobacterium Marinum Granuloma In Striped Bass Morone Saxatilis, D. T. Gauthier, W. K. Vogelbein, C. A. Ottinger

Biological Sciences Faculty Publications

An emerging epizootic of mycobacteriosis currently threatens striped bass Morone saxatilis populations in Chesapeake Bay, USA. Several species of mycobacteria, including Mycobacterium marinum, species resembling M. avium, M. gordonae, M. peregrinum, M. scrofulaceum and M. terrae, and the new species M. shottsii have been isolated from diseased and healthy bass. In this study, we describe the ultrastructure of developing M. marinum granulomas in experimentally infected bass over a period of 45 wk. The primary host response to injected mycobacteria was formation of large macrophage aggregations containing phagocytosed bacilli. M. marinum were always contained within phagosomes. Close …

Cd46-Mediated Transduction Of A Species D Adenovirus Vaccine Improves Mucosal Vaccine Efficacy, Zenaido T. Camacho, Mallory A. Turner, Michael A. Barry, Eric A. Weaver

Nebraska Center for Virology: Faculty Publications

The high levels of preexisting immunity against Adenovirus type 5 (Ad5) have deemed Ad5 unusable for translation as a human vaccine vector. Low seroprevalent alternative viral vectors may be less impacted by preexisting immunity, but they may also have significantly different phenotypes from that of Ad5. In this study we compare species D Ads (26, 28, and 48) to the species C Ad5. In vitro transduction studies show striking differences between the species C and D viruses. Most notably, Ad26 transduced human dendritic cells much more effectively than Ad5. In vivo imaging studies showed strikingly different transgene expression profiles. The …

Phylogenetic Analyses Of Texas Isolates Indicate An Evolving Subtype Of The Clade B Feline Immunodeficiency Viruses, Eric A. Weaver, Ellen W. Collisson, Margaret Slater, Guan Zhu

Nebraska Center for Virology: Faculty Publications

Rigorous phylogenetic analyses were used to compare the nucleotide sequences of feline immunodeficiency virus strains isolated from Texas and throughout the world. The envelope V3-V4 sequences and capsid gene of the Texas isolates formed a cluster between subtypes B and E. Statistical comparisons with other published sequences confirmed that the Texas group is a unique cluster, possibly a new subtype, arising from subtype B.

Dissecting The Loci Of Low-Level Quinine Resistance In Malaria Parasites, Michael T. Ferdig, Roland A. Cooper, Jianbing Mu, Bingbing Deng, Deirdre A. Joy, Xin-Zhuan Su, Thomas E. Wellems

Biological Sciences Faculty Publications

Quinine (QN) remains effective against Plasmodium falciparum, but its decreasing efficacy is documented from different continents. Multiple genes are likely to contribute to the evolution of QN resistance. To locate genes contributing to QN response variation, we have searched a P. falciparum genetic cross for quantitative trait loci (QTL). Results identify additive QTL in segments of chromosomes (Chrs) 13, 7 and 5, and pairwise effects from two additional loci of Chrs 9 and 6 that interact, respectively, with the QTL of Chrs 13 and 7. The mapped segments of Chrs 7 and 5 contain pfcrt, the determinant of …

A Survey Of Antibiotic Resistance Among Coliform Bacteria Isolated From The Missouri River, Sara E. Mcdonnell, Amy M. Treonis

Biology Faculty Publications

The prevalence of antibiotic resistant microorganisms in the environment is not well known but could represent a challenge to maintaining public health in the future. Fecal waste from livestock facilities, where antibiotics are routinely used, is recognized as a significant source of pollution to surface waters in the United States. We collected water from the Missouri River across a winter to spring seasonal change in order to survey the density of coliform bacteria. We tested bacterial isolates for resistance to penicillin, tetracycline, ampicillin, erythromycin, and ciprofloxacin. Coliform density in Missouri River water generally was high throughout the study (0-405 cfu …

Evaluation Of Immunogenicity Of Transgenic Chloroplast Derived Protect, Vijay Koya

Electronic Theses and Dissertations

Anthrax, a fatal bacterial infection is caused by Bacillus anthracis, a gram-positive, spore forming, capsulated, rod shaped organism. Centers for Disease Control (CDC) lists anthrax as Category A biological agent due to its severity of impact on human health, high mortality rate, acuteness of the disease and potential for delivery as a biological weapon. The currently available human vaccine in the United States (AVA anthrax vaccine adsorbed) is prepared from Alum adsorbed formalin treated supernatant culture of toxigenic, non-encapsulated strain of Bacillus anthracis with the principle component being protective antigen (PA83). Evaluation of anthrax vaccine given to nearly 400,000 US …

Comprehensive Analysis Of Class I And Class Ii Hla Antigens And Chronic Hepatitis B Virus Infection, Chloe L. Thio, David L. Thomas, Peter Karacki, Xiaojiang Gao, Darlene Marti, Richard A. Kaslow, James J. Goedert, Margaret Hilgartner, Steffanie A. Strathdee, Priya Duggal, Stephen J. O'Brien, Jacquie Astemborski, Mary Carrington

Biology Faculty Articles

Following an acute hepatitis B virus (HBV) infection, clearance or persistence is determined in part by the vigor and breadth of the host immune response. Since the human leukocyte antigen system (HLA) is an integral component of the immune response, we hypothesized that the highly polymorphic HLA genes are key determinants of viral clearance. HLA class I and II genes were molecularly typed in 194 Caucasian individuals with viral persistence and 342 matched controls who had cleared the virus. A single class I allele, A*0301 (odds ratio [OR], 0.47; 95% confidence interval [CI], 0.30 to 0.72; P = 0.0005) was …

Comparison Of Double Disc And Combined Disc Method For The Detection Of Extended Spectrum Beta Lactamases In Enterobacteriaceae, K Jabeen, A Zafar, Rumina Hasan

Department of Pathology and Laboratory Medicine

Objective:
/="/">To compare double disc approximation and combined disc method for their ability to detect extended spectrum b lactamase (ESBL) production in enterobacteriaceae and determine the percentage of isolates which are falsely reported as sensitive in absence of ESBL detection, in a clinical microbiology laboratory of a tertiary care hospital between September-October 2002.
/="/">Methods:
/="/">Selected isolates were identified according to standard biochemical tests. Disc susceptibility tests were performed according to NCCLS. ESBL detection by combined disc [cefotaxime (30 ug) versus cefotaxime plus clavulanate (30+10 ug)] was compared with detection using double discs [amoxy-clavulanic acid (20+10 ug) and …

Characterization Of Spy1600 A Putative Hyaluronidase Gene In Group A Streptococci, Karin M. Berling

Biological Sciences Theses & Dissertations

Group A Streptococci (GAS), also known as Streptococcus pyogenes, can cause a variety of human diseases ranging from asymptomatic to life threatening. Exactly how a single type of organism is able to inflict such a multitude of diseases remains to be fully understood. One possibility includes the large number of secreted virulence factors expressed by the organism. The recent sequencing of three streptococcal genomes has indicated the existence of several previously unknown genes, some of which may encode possible virulence factors. Among these is Spy1600, which based on its sequence similarities has been proposed to encode a hyaluronidase, a …

Cultivation Of Tropheryma Whipplei From Cerebrospinal Fluid, Matthias Maiwald, Axel Von Herbay, David N. Fredricks, Cleber C. Ouverney, Jon C. Kosek, David A. Relman

Faculty Publications, Biological Sciences

Whipple disease (WD) is a systemic disorder caused by the bacterium Tropheryma whipplei. Since the recognition of a bacterial etiology in 1961, many attempts have been made to cultivate this bacterium in vitro. It was eventually isolated, in 2000, from an infected heart valve, in coculture with human fibroblasts. Here we report the isolation of 2 new strains of T. whipplei from cerebrospinal fluid (CSF) of 2 patients with intestinal WD but no neurological signs or symptoms. One culture-positive specimen was obtained before treatment; the other was obtained 12 months after discontinuation of therapy, at a time of intestinal remission. …

To The Editor: Reply To Sarmati, Brad P. Brayfield, John T. West, Charles D. Mitchell, Charles Wood

Nebraska Center for Virology: Faculty Publications

The letter by Sarmati et al. [1] presents data indicating that they were unable to find a significant correlation between human herpesvirus (HHV)–8 seropositivity and a history of spontaneous abortion in a group of 245 human immunodeficiency virus (HIV) type 1–seronegative women but that they did observe a correlation between high HHV-8 antibody titers (≥1:1280) and spontaneous abortion. Although it is possible that an increased risk of spontaneous abortion may be associated with active infection with HHV-8, at this point there is not enough evidence to support such an association. Given that several human herpes viruses are well-known agents of …

Rapid Detection Of Listeria Monocytogenes, Wim Lippens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Listeria monocytogenes is a foodbome pathogen that can cause severe illness and even death. It is found in dairy and meat products. The focus is on rapid detection since conventional methods are time consuming (4-5 days). Pre-enrichment steps, as part of those methods, are time consuming. Our objective was to develop a detection system without a pre-enrichment step, giving a final result within 2 to 4 h.

In the concept of "the need for speed," a detection system with an antibody-based capture technique, followed by polymerase chain reaction (PCR), was developed. Glass beads coated with a Listeria polyclonal antibody were …

Real-Time Study Of Multidrug Resistance Mechanism In Pseudomonas Aeruginosa Using Nanoparticle Optics And Single Live Cell Imaging, Sophia Vasou Kyriacou

Chemistry & Biochemistry Theses & Dissertations

This thesis centers on the study of the xenobiotic efflux system in Pseudomonas aeruginosa, which is a ubiquitous bacterium. It resists many structurally and functionally diverse substrates due to expression of Mex-extrusion pumps, including MexAB-OprM, MexCD-OprJ, MexEF-OprN and MexXY-OprM systems. Despite extensive research, the structure and mechanism of multidrug resistance is unclear (1-9). For example, (i) how do MexA, MexB and OprM proteins assemble to extrude antibiotics? (ii) What is the antibiotic susceptibility of MexA, MexB, and OprM proteins? (iii) How do substrates cross the outer membrane of P. aeruginosa? (iv) Where are antibiotics accumulated inside the cell? This thesis …

Postnatal Human Herpesvirus 8 And Human Immunodeficiency Virus Type 1 Infection In Mothers And Infants From Zambia, Brad P. Brayfield, Saul Phiri, Chipepo Kankasa, Jubra Muyanga, Hamakwa Mantina, Geoffrey Kwenda, John T. West, Ganapati Bhat, Dave B. Marx, Winslow Klaskala, Charles D. Mitchell, Charles Wood

Nebraska Center for Virology: Faculty Publications

The specific route and timing of human herpesvirus (HHV) 8 infection in regions where Kaposi sarcoma is endemic are not known. HHV-8 infection and any risk factors that may be associated with HHV-8, including human immunodeficiency virus (HIV) type 1 infection, were monitored during the 12-month post-delivery period for 416 mothers and 485 infants from Lusaka, Zambia. HHV-8 incident infection rates during this period were 3.2 and 5.3 infections/100 person-years for infants and mothers, respectively. HHV-8 infection among infants was not associated with HHV-8 or HIV-1 infection in the mother. Among the HHV-8–positive infants, 2 of 12 tested were found …

Regulation Of Type 1 Diabetes By A Self-Mhc Class Ii Peptide: Role Of Transforming Growth Factor Beta (Tgf-Beta)., Bhagirath Singh, R Mukherjee, P Chaturvedi, Babita Agrawal

Microbiology & Immunology Publications

The present study was undertaken to analyze the regulatory T cells generated in response to class I derived self-I-A beta(g7) (54-76) peptide. It was observed T cells from young unprimed type 1 diabetes (T1D) prone NOD mice did not respond to self-I-A beta(g7) (54-76) peptide although T cells from primed young NOD mice showed a strong response. T cells from young unprimed BALB/c mice responded to self-I-A beta(d) (62-78) peptide. However, a breakdown of tolerance to these peptides was observed with age in both the strains. Culture supernatant from I-A beta(g7) (54-76) peptide-primed cells secreted large amounts of TGF-beta and …

Structural Analyses Of Phycodnaviridae And Iridoviridae, Alan A. Simpson, Narayanasamy Nandhagopal, James L. Van Etten, Michael G. Rossmann

Nebraska Center for Virology: Faculty Publications

The Phycodnaviridae, Iridoviridae and related viruses, with diameters of 1500±2000 A Ê , are formed from large trigonal arrays of hexagonally close-packed capsomers forming the faces of icosahedra [Yan et al. (2000), Nature Struct. Biol. 7, 101-103; Nandhagopal et al. (2002), Proc. Natl Acad. Sci. USA, 99, 14758-14763]. Caspar and Klug predicted that such structures could be assembled from hexameric capsomers [Caspar & Klug (1962), Cold Spring Harbor. Symp. Quant. Biol. 27, 1-24], as was subsequently found in numerous icosahedral viruses. During the course of evolution, some viruses, including the virus families …

Functional Implications In Apoptosis By Interferon Inducible Gene Product 1-8d, The Binding Protein To Adenovirus Preterminal Protein, Insil Joung, Peter C. Angeletti, Jeffrey A. Engler

Nebraska Center for Virology: Faculty Publications

Adenovirus (Ad) precursor to the terminal protein (pTP) plays an essential roles in the viral DNA

replication. Ad pTP serves as a primer for the synthesis of a new DNA strand during the initiation

step of replication. In addition, Ad pTP forms organized spherical replication foci on the nuclear

matrix (NM) and anchors the viral genome to the NM. Here we identified the interferon inducible

gene product 1-8D (Inid) as a pTP binding protein by using a two-hybrid screen of a HeLa cDNA

library. Of the clones obtained in this assay, nine were identical to the Inid, a 13-kDa polypeptide …