Microbiology Commons^™

Surveillance Of Emerging Livestock Viruses, Faten A. Okda

Electronic Theses and Dissertations

Accurate and rapid diagnostic tests are essential for the management and control of emerging infectious diseases. Therefore, the overall goals of studies presented in this dissertation were to provide improved diagnostic and surveillance capabilities for several emerging viral diseases impacting the livestock industry and to provide insight into appropriate control strategies. Recent, severe outbreaks of porcine epidemic diarrhea virus (PEDV) in Asia and North America highlighted the need for well-validated diagnostic tests for identification of PEDV infected animals and evaluation of their immune status. PEDV was first detected in the U.S. in May 2013 and another swine coronavirus, porcine deltacoronavirus …

Orientia Tsutsugamushi Secretes Two Ankyrin Repeat-Containing Effectors Via A Type 1 Secretion System To Inhibit Host Nf-Κb Function, Sean M. Evans

Theses and Dissertations

Scrub typhus is a potentially fatal infection that threatens one billion persons in the Asia-Pacific region and is caused by the obligate intracellular bacterium, Orientia tsutsugamushi. How this organism facilitates its intracellular survival and pathogenesis is poorly understood. Intracellular bacterial pathogens utilize the Type 1 (T1SS) or Type 4 secretion system (T4SS) to translocate ankyrin repeat-containing proteins (Anks) into the host cell to modulate host cell processes. The O. tsutsugamushi genome encodes one of the largest known bacterial Ank libraries as well as Type 1 and Type 4 secretion systems (T1SS and T4SS), which are expressed during infection. In …

Actionable Patient Safety Solution (Apss) #3b: Antimicrobial Stewardship: The Role Of A Pharmacy And The Microbiology Lab In Patient Safety, Jerika Lam, Jason Yamaki, Ron Jordan, Celine Peters, Steven Barker, Michael Ramsay, Ariana Longley, Joe Kiani

Pharmacy Faculty Articles and Research

This report presents a plan of action for introducing an Antimicrobial Stewardship Plan (ASP) to combat the inappopriate use of antimicrobial drugs, which are a significant cause of patient morbidity and mortality.

Senecavirus A: Epidemiology, Pathogenesis And Infection Dynamics, Lok Raj Joshi

Electronic Theses and Dissertations

Senecavirus A (SVA) is a positive sense single-stranded virus that belongs to the genus Senecavirus within the family Picornaviridae. Senecavirus has been present in US swine population since 1988. However, there have been only a few reports of SVA associated with disease in last two decades. In late 2014 early 2015, a sudden increase in the number of cases of Senecavirus A associated with vesicular disease was observed in Brazil, the US and China. Affected pigs presented vesicles on snout, coronary band, and dewclaw. Additionaly, increased neonatal mortality has been reported in the field. Many aspects of SVA epidemiology, …

Characterization Of A New Chlorovirus Type With Permissive And Non-Permissive Features On Phylogenetically Related Algal Strains, Cristian F. Quispe, Ahmed Esmael, Olivia Sonderman, Michelle Mcquinn, Irina Agarkova, Mohammed Battah, Garry A. Duncan, David D. Dunigan, Timothy P. L. Smith, Cristina Decastro, Immacolata Speciale, Fangrui Ma, James L. Van Etten

Nebraska Center for Virology: Faculty Publications

A previous report indicated that prototype chlorovirus PBCV-1 replicated in two Chlorella variabilis algal strains, NC64A and Syngen 2-3, that are ex-endosymbionts isolated from the protozoan Paramecium bursaria. Surprisingly, plaque-forming viruses on Syngen 2-3 lawns were often higher than on NC64A lawns from indigenous water samples. These differences led to the discovery of viruses that exclusively replicate in Syngen 2-3 cells, named Only Syngen (OSy) viruses. OSy-NE5, the prototype virus for the proposed new species, had a linear dsDNA genome of 327 kb with 44-nucleotide-long, incompletely base-paired, covalently closed hairpin ends. Each hairpin structure was followed by an identical …

Role Of Intracellular Growth During The Gastrointestinal Stage Of Listeria Monocytogenes Infection, Grant Steven Jones

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

Listeria monocytogenes is a facultative intracellular bacterium that causes foodborne disease in humans. L. monocytogenes invade the gut mucosa and then disseminate, causing systemic infections associated with high mortality rates in immunocompromised individuals. It is unknown how L. monocytogenes traffic to the mesenteric lymph nodes, which represent an important bottleneck for systemic spread. In addition, little is known about the gastrointestinal stage of infection due to the general resistance of mice to oral infection with L. monocytogenes. Our laboratory developed a novel foodborne mouse model of listeriosis utilizing a murinized strain of L. monocytogenes to investigate the gastrointestinal stage …

A First Look At The Microbial Community Of Rabidosa Rabida, A Wolf Spider In Searcy, Arkansas, Patricia Rivera, Ryan Stork, Amber Hug

Journal of the Arkansas Academy of Science

Many diverse animal models have been used to explore the interactions between host organisms and their microbiota. Increased understanding of microbe-host interactions could lead to improved healthcare and drug development. Spiders have venom, digestive fluid, and body fluid components that have been suggested to possess antimicrobial properties that could lead to new and interesting host-microbe interactions. While studies have been published on interactions between bacteria affecting the immune function and behavior of spiders, the spider microbiome has not been established to date. Excreta and body swabs were collected from Rabidosa rabida, a wolf spider typically found on tall grass …

Measuring Bacterial Growth Using A 3d-Printable Spectrometer, Samuel R. Bunting

Williams Honors College, Honors Research Projects

Visible light spectroscopy is a commonly used technique for measuring the growth of bacterial cultures, and growth curves provide broadly important data. However, the equipment and resources required for these experiments has been restricted to higher education and industry due to high cost and sophistication. We have previously reported on an inexpensive, 3D-printable photospectrometer called the SpecPhone. This device utilizes an iPhone as the camera, along with several other, inexpensive additions to make a fully functional spectrometer. Here, the application of the SpecPhone is expanded to the quantification of actively dividing E. coli cultures. Two protocols have been developed; one …

Biomarkers Of Sepsis: A Retrospective Approach, Jose M. Roberts

Williams Honors College, Honors Research Projects

Background: Biomarkers are taking the spotlight in becoming the norm for early diagnoses. Sepsis is an inflammatory disease that increases metabolic rate in children. The first biomarker is hyponatremia. Hyponatremia is a frequent electrolyte imbalance in clinical practice, often observed in children with inflammatory disease and infection. Presence of hyponatremia is associated with electrical signaling imbalances, inflammation and renal dysfunction. The clinical value of hyponatremia in pediatric patients is unknown. The C-reactive protein is a second biomarker. Its presence signifies that necrotic cells and inflammation are present.

Objectives: To evaluate the use of biomarkers in children seen in the Emergency …

Contribution Of A Class Ii Ribonucleotide Reductase To The Manganese Dependence Of Streptococcus Sanguinis, John L. Smith

Theses and Dissertations

Manganese-deficient Streptococcus sanguinis mutants exhibit a dramatic decrease in virulence for infective endocarditis and in aerobic growth in manganese-limited media. Loss of activity of a manganese-dependent, oxygen-dependent ribonucleotide reductase (RNR) could explain the decrease in virulence. When the genes encoding this RNR are deleted, there is no growth of the mutant in aerobic broth culture or in an animal model. Testing the contribution of the aerobic RNR to the phenotype of a manganese transporter mutant, a heterologous class II RNR from Lactobacillus leichmannii called NrdJ that requires B₁₂ rather than manganese as a cofactor was previously introduced into an …

Antimicrobial Activity Of Fractionated Borohydride-Capped And Electrochemical Colloidal Silver, Marjorie M. Markopoulos

Browse all Theses and Dissertations

Silver nanoparticles (AgNPs) and ionic silver (Ag+) are known to be broad-spectrum antimicrobial agents. Recent studies show these agents may be an alternative to the most widely used drinking water disinfectant, chlorine. Chlorine is a toxic industrial chemical with a lethal concentration of 430 ppm after 30 minutes. Additionally, chlorine can react with naturally occurring materials to produce a number of disinfection byproducts such as chloroform and trihalomethanes. Some of these byproducts pose cancer risks in addition to other negative impacts to human health. These would be eliminated with the use of Ag+ or AgNPs. The main goal of this …

Amixicile Inhibits Anaerobic Bacteria Within An Oral Microbiome Derived From Patients With Chronic Periodontitis, Kane Ramsey

Theses and Dissertations

Periodontitis is a chronic inflammatory disease caused by pathogenic bacteria residing in a complex biofilm within a susceptible host. Amixicile is a non-toxic, readily bioavailable novel antimicrobial that targets strict anaerobes through inhibition of the activity of Pyruvate Ferredoxin Oxidoreductase (PFOR), a major enzyme mediating oxidative decarboxylation of pyruvate. Our study aimed to evaluate the efficacy of amixicile, when compared to metronidazole, in inhibiting the growth of bacteria present in a microbiome harvested from patients with chronic periodontitis.

Plaque samples were harvested from patients with severe chronic periodontitis and cultured under anaerobic conditions. The microbiomes were grown in the presence …

Readiness For Antimicrobial Resistance (Amr) Surveillance In Pakistan; A Model For Laboratory Strengthening, Dania Khalid Saeed, Rumina Hasan, Mahwish Naim, Afia Zafar, Erum Khan, Kauser Jabeen, Seema Irfan, Imran Ahmed Haq, Mohammad Zeeshan, Zabin Wajidali, Joveria Farooqi, Sadia Shakoor, Abdul Chagla, Jason Roy

Department of Pathology and Laboratory Medicine

Background: Limited capacity of laboratories for antimicrobial susceptibility testing (AST) presents a critical diagnostic bottleneck in resource limited countries. This paper aims to identify such gaps and to explore whether laboratory networks could contribute towards improving AST in low resource settings.
Methods: A self-assessment tool to assess antimicrobial susceptibility testing capacity was administered as a pre-workshop activity to participants from 30 microbiology laboratories in 3 cities in Pakistan. Data from public and private laboratories was analyzed and capacity of each scored in percentage terms. Laboratories from Karachi were invited to join a support network. A cohort of five laboratories that …

Phenotypic Low-Level Isoniazid Resistance As A Marker To Predict Ethionamide Resistance In Mycobacterium Tuberculosis, Salima Qamar, Joveria Q. Farooqi, Kausar Jabeen, Rumina Hasan

Department of Pathology and Laboratory Medicine

Background: Tuberculosis is one of the most prevalent diseases in Pakistan. Pakistan has the highest burden of MDR-TB in the Eastern Mediterranean region. Ethionamide is an anti-tuberculous drug frequently used to treat MDR-TB. Its drug susceptibility testing is not easily available in resource limited settings. Since it acts on the same target protein as isoniazid (inhA protein encoded by inhA gene), we sought to find out if phenotypic isoniazid resistance can be a marker of ethionamide resistance.
Materials and Methods: This was a retrospective observational study conducted at the Aga Khan University hospital section of microbiology. Data was retrieved between …

Utility Of Peripheral Film Findings And Its Correlation With Automated Analyzer - An Audit From Tertiary Care Hospital, Sidra Asad, Imran Ahmed, Natasha Ali

Department of Pathology and Laboratory Medicine

Background and Objective: With the advent of automated hematology analyzer, the use of traditional microscopy of blood film has become limited. The objective of our study was to determine the percentage of peripheral blood smear review in our institution in the era of automation and to identify reasons of manual review.
Materials and Methods: This was a prospective audit from January 1, 2015, to January 15, 2015. Consecutive complete blood count (CBC) samples and peripheral smear requests made up the sample size. All age groups and genders were included. CBCs were performed on Sysmex XE-5000. The variables to be analyzed …

Papillary Craniopharyngioma: A Clinicopathologic Study Of A Rare Entity From A Major Tertiary Care Center In Pakistan, Muhammad Usman Tariq, Nasir Ud Din, Zubair Ahmad, Wasim Memon

Department of Pathology and Laboratory Medicine

Background: Papillary craniopharyngioma (PCP) are uncommon variants of craniopharyngiomas (CP), which are benign epithelial neoplasms of the sellar and suprasellar region. Histologically, PCPs are typically composed of well-differentiated stratified squamous epithelium; however, focal variations are not uncommon. A distinction from other lesions of the region, despite being difficult to achieve due to the overlapping radiological and clinical features, is important for adequate treatment to be administered.
Objective: Our aim was to study the clinical and histological features of PCP with emphasis on features that are helpful in its distinction from other lesions that are similar in appearance.
Materials and Methods: …

Rapid Detection Of In Vitro Antituberculous Drug Resistance Among Smear-Positive Respiratory Samples Using Microcolony Detection-Based Direct Drug Susceptibility Testing Method, Irim Iftikhar, Seema Irfan, Joveria Farooqi, Zahida Azizullah, Rumina Hasan

Department of Pathology and Laboratory Medicine

Background: With the rise in multidrug-resistant tuberculosis, there is a search for newer techniques that will rapidly detect drug-resistant Mycobacterium tuberculosis. Although molecular techniques can detect resistance, culture is still considered gold standard, especially in resource-limited settings where quick, cheap, and easy techniques are needed. The aim of the study was to evaluate microcolony method thin layer agar (TLA) for quick detection of resistance against the first- and second-line antituberculous drugs in clinical isolates. This was a cross-sectional study performed at Aga Khan University Hospital.
Material and Methods: A total of 87 Z-N stain smear-positive pulmonary samples were received and …

Reactivation Of Hiv-1 Proviruses In Immune-Compromised Mice Engrafted With Human Voa-Negative Cd4+ T Cells, Zhe Yuan, Guobin Kang, Wuxun Lu, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

Background: HIV-1 infection remains incurable on antiretroviral therapy (ART) due to virus latency. To date, enhanced co-culture assays, including viral outgrowth assays (VOA), are commonly used to measure HIV-1 latent reservoirs and evaluate latency-reversing agents (LRAs). However, VOA can only reactivate a small fraction of intact proviruses.

Methods: To explore the utility of NOD scid gamma (NSG) mice as an in vivo model to reactivate HIV-1 proviruses from VOA-negative CD4+ T cells, resting CD4+ T cells from an HIV-1 latently infected individual were isolated and the human CD4+ T cells corresponding to VOA-positive and VOA-negative CD4+ T cells were engrafted …

Using Extremophile Bacteriophage Discovery In A Stem Education Professional Development Partnership To Explore Model Classroom Research Experiences Integrating The Three Dimentions Of The Next Generation Science Standards, Carrie L. Boudreau Ms

All Student Scholarship

The National Research Council’s (NRC) A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas describes a vision of what it means to be proficient in science. The project discussed in this thesis was developed with a NIH SEPA Grant 8R25OD010937 to the Virology and Electron Microscopy Laboratory at the University of Southern Maine (USM) under the direction of Dr. S. Monroe Duboise. The goal of the project was to explore using discovery of extreme environment bacteria and their bacteriophages as a model for using the three dimensions of learning to teach Next Generation Science Standards (NGSS). Specifically, …

Structure-Function Investigation Of Proteins Involved In Cellulose Biosynthesis By Escherichia Coli, Thomas Brenner

Theses and Dissertations (Comprehensive)

Bacteria thrive within multicellular communities called biofilms consisting of a self-produced matrix. Biofilm matrices improve bacterial adherence to surfaces while creating a barrier from host immune responses, disinfectants, antibiotics and other environmental factors. Persistent colonization by the widely distributed pathogens, Escherichia coli and Salmonella spp., has been linked to production of biofilms composed of the exopolysaccharide cellulose. Cellulose-containing biofilms are also important to Acetobacter, Sarcina, Rhizobium and Agrobacterium species to form symbiotic and pathogenic interactions. In Enterobacteriaceae, two operons (bcsABZC and bcsEFG) are proposed to encode for proteins that form a cellulose biosynthetic complex that spans the …

A Systems Biology Approach For Predicting Essential Genes And Deciphering Their Dynamics Under Stress In Streptococcus Sanguinis, Fadi El-Rami

Theses and Dissertations

Infectious diseases are the top leading cause of death worldwide. Identifying essential genes, genes indispensable for survival, has been proven indispensable in defining new therapeutic targets against pathogens, major elements of the minimal set genome to be harnessed in synthetic biology, and determinants of evolutionary relationships of phylogenetically distant species. Thus, essentiality studies promise valuable revenues that can decipher much of biological complexities.

Taking advantage of the available microbial sequences and the essentiality studies conducted in various microbial models, we proposed a framework for the prediction of essential genes based on our experimentally verified knowledge of the pathways involved in …

Controlling Brochothrix Thermosphacta As A Spoilage Risk Using In Package Atmospheric Cold Plasma, Apurva Patange, Daniela Boehm, Carmen Bueno-Ferrer, Patrick J. Cullen, Paula Bourke

Articles

Brochothrix thermosphacta is a predominant spoilage microorganism in meat and its control in processing environments is important to maintain meat product quality. Atmospheric cold plasma is of interest for control of pathogenic and spoilage microorganisms in foods. This study ascertained the potential of dielectric barrier discharge atmospheric cold plasma (DBD-ACP) for control of B. thermosphacta in response to key parameters such as treatment time, voltage level, interactions with media composition and post treatment storage conditions. Challenge populations were evaluated as suspensions in PBS, as biofilms in meat model medium and surface attached on raw lamb chops under MAP.

ACP treatment …

A Rare Case Of Erythema Elevatum Diutinum Presenting As Diffuse Neuropathy, G H. Nguyen, E L. Guo, D Norris

Faculty, Staff and Students Publications

No abstract provided.

Development And Characterization Of Histidine-Tagged Hpv16 L2 And Ms2-Arginine-Tagged Recombinant Proteins For Downstream Processes, Tahiyat Alothaim

Dissertations, Master's Theses and Master's Reports

Human papillomaviruses (HPVs) are the most common sexually transmitted infections. Persistent infection with HPV can lead to anogenital cancers including head and neck cancers. Three prophylactic vaccines have been approved to prevent against some types of HPV infection. However, the vaccines are HPV-type specific and protect mostly against the HPV types included in the vaccines. To offer broader protection against more HPV types, studies in the field are developing candidate vaccines targeting a conserved minor capsid protein, L2. Nevertheless, reagents for developing and assessing L2 vaccines are limited. For example, antibodies to assess the antigenicity of some L2 epitopes are …

Influence Of Maternal Breast Milk Ingestion On Acquisition Of The Intestinal Microbiome In Preterm Infants, Katherine E Gregory, Buck S Samuel, Pearl Houghteling, Guru Shan, Frederick M Ausubel, Ruslan I Sadreyev, W Allan Walker

Faculty, Staff and Students Publications

BACKGROUND: The initial acquisition and early development of the intestinal microbiome during infancy are important to human health across the lifespan. Mode of birth, antibiotic administration, environment of care, and nutrition have all been shown to play a role in the assembly of the intestinal microbiome during early life. For preterm infants, who are disproportionately at risk of inflammatory intestinal disease (i.e., necrotizing enterocolitis), a unique set of clinical factors influence the establishment of the microbiome. The purpose of this study was to establish the influence of nutritional exposures on the intestinal microbiome in a cohort of preterm infants early …

Comparative Genomic Analysis Of Two Serotype 1/2b Listeria Monocytogenes Isolates From Analogous Environmental Niches Demonstrates The Influence Of Hypervariable Hotspots In Defining Pathogenesis, Aidan Casey, Kieran Jordan, Aidan Coffey, Edward M. Fox, Olivia Mcauliffe

Department of Biological Sciences Publications

The vast majority of clinical human listeriosis cases are caused by serotype 1/2a, 1/2b, 1/2c, and 4b isolates of Listeria monocytogenes. The ability of L. monocytogenes to establish a systemic listeriosis infection within a host organism relies on a combination of genes that are involved in cell recognition, internalization, evasion of host defenses, and in vitro survival and growth. Recently, whole genome sequencing and comparative genomic analysis have proven to be powerful tools for the identification of these virulence-associated genes in L. monocytogenes. In this study, two serotype 1/2b strains of L. monocytogenes with analogous isolation sources, but …

The Vibrio Cholerae Minor Pilin Tcpb Initiates Assembly And Retraction Of The Toxin-Coregulated Pilus, Dixon Ng, Tony Harn, Tuba Altindal, Subramania Kolappan, Jarrad Marles, Rajan Lala, Ingrid Spielman, Yang Gao, Caitlyn Hauke, Gabriela Kovacikova

Dartmouth Scholarship

Type IV pilus (T4P) systems are complex molecular machines that polymerize major pilin proteins into thin filaments displayed on bacterial surfaces. Pilus functions require rapid extension and depolymerization of the pilus, powered by the assembly and retraction ATPases, respectively. A set of low abundance minor pilins influences pilus dynamics by unknown mechanisms. The Vibrio cholerae toxin-coregulated pilus (TCP) is among the simplest of the T4P systems, having a single minor pilin TcpB and lacking a retraction ATPase. Here we show that TcpB, like its homolog CofB, initiates pilus assembly. TcpB co-localizes with the pili but at extremely low levels, equivalent …

Erratum To: Neonatal Hyperbilirubinemia In Infants With G6pd C.563c>T Variant, Bushra Moiz, Amna Nasir, Sarosh Ahmed Khan, Saleema Amin Kherani, Maqbool Qadir

Department of Pathology and Laboratory Medicine

No abstract provided.

Epidemiology Of White Spot Syndrome Virus In The Daggerblade Grass Shrimp (Palaemonetes Pugio) And The Gulf Sand Fiddler Crab (Uca Panacea), Muhammad

Dissertations

Ever since the first outbreaks of White spot syndrome virus (WSSV), which causes White Spot Disease (WSD), in Asia in the early 1990s, the pathogen has been a major constraint to the profitability of the shrimp aquaculture industry across the globe. WSSV has a broad host range and is routinely detected in wild decapod crustaceans. In the present study, two common species in the tidal salt marsh along the northern coast of the Gulf of Mexico, the daggerblade grass shrimp (Palaemonetes pugio) and the Gulf sand fiddler crab (Uca panacea), were investigated for their role as …

A Microbiomic Approach To The Characterization Of The Impacts And Influences Of Viral, Bacterial, And Harmful Algal Bloom Toxins On The Bottlenose Dolphin, Corey David Russo

Dissertations

As apex predators that display high site fidelity Tursiops truncatus (bottlenose dolphin) are indicators of marine ecosystem health. Bottlenose dolphins, additionally, display pathogenesis and immune response similar to that of humans. Humans and coastal bottlenose dolphins, in particular, are constantly exposed to the same industrial, agricultural and domestic toxins and pathogens, contaminants and pollutants. Thus, studies on the bottlenose dolphin are also valuable in bridging the gap between ocean and human health. Bottlenose dolphins are susceptible to viral bacterial and toxin infection. Infection in the bottlenose dolphin manifests itself in the form of mass stranding events, unusual mortality events, chronic …