Digital Commons Network^™

Mycological Study For A Management Plan Of A Neotropical Show Cave (Brazil), Erika Linzi Silva Taylor, Maria Aparecida De Resende Stoianoff, Rodrigo Lopes Ferreira

International Journal of Speleology

Caves are stable environments with characteristics favoring the development of microorganisms. The allocthonous input of organic matter and microbes into the warm Neotropical caves may favor the development of filamentous fungi, including pathogenic species. Histoplasma capsulatum is a pathogenic species commonly found in caves and associated with bat and bird guano. Many Brazilian caves have been historically visited due to scenic and religious tourism. The objective of this study was to perform a microbiology study for a management plan of a show cave in Brazil, focusing on the presence and distribution of pathogenic and opportunistic fungi in the cave. Statistics …

A Quadruplex Real-Time Pcr Assay For The Rapid Detection And Differentiation Of The Burkholderia Pseudomallei Complex: B. Mallei, B. Pseudomallei, And B. Thailandensis, Chinn-Woan Lowe

Theses and Dissertations

Methods for the rapid detection and differentiation of the Burkholderia pseudomallei complex comprising B. pseudomallei, B. mallei, and B. thailandensis, have been the topic of recent research due to the high degree of phenotypic and genotypic similarities of these species. B. pseudomallei and B. mallei are the causative agents of melioidosis and glanders, respectively. B. pseudomallei and B. mallei are recognized by the CDC as tier 1 select agents. Although B. thailandensis is generally avirulent in mammals, this species displays very similar phenotypic characteristics to that of B. pseudomallei. Optimal identification of these species remains problematic, …

Multidrug-Resistant Tuberculosis: Strategies For Identification And Control, Wendy Chao, Dr. Richard Robison

Journal of Undergraduate Research

After over a century of decline, tuberculosis (TB) has re-emerged as the leading killer among infectious diseases. In addition, Mycobacterium tuberculosis, the causative agent of TB, has developed strains resistant to multiple antibiotics, making the disease increasingly difficult to treat.

Barrier To Autointegration Factor (Baf) Inhibits Vaccinia Virus Intermediate Transcription In The Absence Of The Viral B1 Kinase, Nouhou Ibrahim, April Wicklund, Augusta Jamin, Matthew S. Wiebe

Nebraska Center for Virology: Faculty Publications

Barrier to autointegration factor (BAF/BANF1) is a cellular DNA-binding protein found in the nucleus and cytoplasm. Cytoplasmic BAF binds to foreign DNA and can act as a defense against vaccinia DNA replication. To evade BAF, vaccinia expresses the B1 kinase, which phosphorylates BAF and blocks its ability to bind DNA. Interestingly, B1 is also needed for viral intermediate gene expression via an unknown mechanism. Therefore, we evaluated the impact of B1-BAF signaling on vaccinia transcription. Strikingly, the decrease in vaccinia transcription caused by loss of B1 can be rescued by depletion of BAF. The repressive action of BAF is greatest …

Identification And Characterization Of An Effective Antimicrobial Peptide Defensin And Its Effects On Transmission Efficiency, Kody Johnson, Dr. David Erickson

Journal of Undergraduate Research

Among many transmissible infectious diseases falls the Bubonic Plague, a disease that is caused by Yersinia pestis, a bacterium. It is still a concern because there have been human cases as recent as last year in our home state of Utah. While health care has advanced significantly since the last large plague epidemic, there are still areas of the world where health care is not as efficient or advanced and it is in these areas that this disease causes the greatest harm.

Identification And Characterization Of An Effective Antimicrobial Peptide Defensin And Its Effects On Transmission Efficiency, Kody Johnson, Dr. David Erickson

Journal of Undergraduate Research

Among many transmissible infectious diseases falls the Bubonic Plague, a disease that is caused by Yersinia pestis, a bacterium. It is still a concern because there have been human cases as recent as two years ago in our home state of Utah. While health care has advanced significantly since the last large plague epidemic, there are still areas of the world where health care is not as efficient or advanced and it is in these areas that this disease causes the greatest harm.

A Supramolecular Strategy To Assemble Multifunctional Viral Nanoparticles, Limin Chen, Xia Zhao, Yuan Lin, Yubin Huang, Qian Wang

Faculty Publications

Using a one-pot approach driven by the supramolecular interaction between β-cyclodextrin and adamantyl moieties, multifunctional viral nanoparticles can be facilely formulated for biomedical applications.

Molecular Detection Of Tick-Borne Pathogens Associated With Ixodid Tick Species Infesting Migratory Songbirds And Ruminants, Nabanita Mukherjee

Master's Theses

Ticks are hematophagous arthropods and capable of inoculating various infectious agents to their vertebrate hosts. Ticks attached to birds and ruminants are capable of carrying tick-transmitted microorganisms. In our study, the prevalence of tick-borne pathogens was examined in ticks infesting migratory songbirds and Pakistani ruminants. During spring migration seasons, ticks were removed from northward-migrating songbirds in Louisiana and identified as Amblyomma Jongirostre, Amblyomma nodosum, Amb/yomma ca/caratum, Amblyomma maculatum, and Haemaphysalis species, all are considered as Neotropical ticks. Ticks removed from ruminants were identified as Hya/omma anatolicum, Hyalomma dromedarii, Rhipicephalus microplus, and Rhipicephalus sanguineus. A total of 112 and 72 bacterial …

Development And Characterization Of An In Vitro Four-Species Anaerobic Dental Biofilm Model, Fernando Andrade

Dissertations and Theses (Open Access)

Dental caries is the most common chronic disease worldwide. It is characterized by the demineralization of tooth enamel caused by acid produced by cariogenic dental bacteria growing on tooth surfaces, termed bacterial biofilms. Cariogenesis is a complex biological process that is influence by multiple factors and is not attributed to a sole causative agent. Instead, caries is associated with multispecies microbial biofilm communities composed of some bacterial species that directly influence the development of a caries lesion and other species that are seemingly benign but must contribute to the community in an uncharacterized way. Clinical analysis of dental caries and …

Coccidia Of Gerbils From Mongolia, Ethan Thomas Jensen

School of Biological Sciences: Dissertations, Theses, and Student Research

In this study, gerbils collected in the Mongolia over the summers of 2009-2012 were examined for coccidia. In total, 171 gerbils of three species from 22 localities were examined for coccidia. Coccidian oocysts were identified from 21 gerbils, but those found in 1 of those gerbils were probably pseudoparasites of the host from which they were recovered. From the remaining 20 gerbils, 7 morphotypes of Eimeria and 1 morphotype of Isospora were identified. Four of the 7 morphotypes of Eimeria were attributed to new species which were described in this study. In addition, 10 previously described species of Eimeria were …

Population Genetics And Drug Resistance Markers: An Essential For Malaria Surveillance In Pakistan, Afsheen Raza, Mohammad Asim Beg

Department of Pathology and Laboratory Medicine

Plasmodium (P.) vivax is the prevalent malarial species accounting for 70% of malaria cases in Pakistan. However, baseline epidemiological data on P. vivax population structure and drug resistance are lacking from Pakistan. For population structure studies, molecular genetic markers, circumsporozoite protein (csp) and merozoite surface protein-1 (msp-1) are considered useful as these play an important role in P. vivax survival under immune and environmental pressure. Furthermore, these genes have also been identified as suitable candidates for vaccine development. While efforts for effective vaccine are underway, anti-malarial agents remain the mainstay for control. Evidence of resistance against commonly used anti-malarial agents, …

Antimycobacterial And Cytotoxicity Evaluation Of The Constituents Of Monodora Carolinae, Nyangi Magori, Stephen S Nyandoro, Joan Je Munissi, Matthias Heydenreich

Tanzania Journal of Science

Phytochemical investigation of the stem bark of the recently described species Monodora carolinae (Annonaceae) afforded prenylindole derivatives (E)-4-(1H-indol-6-yl)-but-3-en-2-one (1), 5-formylindole (2), fatty acid (Z)-hexade-7-enoic acid (3) and the lignanamide cannabisin B (4). The structures of the isolated compounds were established using NMR and MS analyses. The antimycobacterial activities of the extracts and isolated compounds were evaluated against Mycobacterium madagascariense (MM) and M. indicus pranii (MIP) using the two-fold microtitre dilution method. While the extracts exhibited minimum inhibitory concentration (MIC) ranging from 500 – 1000 µg/mL, the isolated compounds were 125 – 250 µg/mL, indicating very low activity. Cytotoxic effects were …

Characterization Of The Gut Microbiota And Colitogenic Bacterial Species In Core 1 O-Glycans Deficient Mice, Maria E. Perez-Munoz

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Mucus is one important component of the intestinal mucosal barrier, and loss of its functionality is associated with colitis in humans and mice. Mice deficient in core 1 O-glycans (TM-IEC C1galt1^-/-) display a thinner mucus layer upon mutation of the glycosyltransferase enzyme (C1GALT1) responsible for core 1 O-glycans attachment, thus constituting an experimental model for human Ulcerative Colitis (UC). Under conventional conditions, these mice experience spontaneous inflammation of the colon. However, the exact role of the microbiota in colitis development in these mice has not been systematically investigated.

Aimed to gain insights into the role of …

In Vitro Selection Of Chloroquine Tolerant Plasmodium Falciparum Parasites, Daniel A. Daley

Biological Sciences Theses & Dissertations

Malaria is among the most devastating human diseases, and a majority of lethal cases are caused by the protozoan parasite, Plasmodiumfalciparum. The emergence of multi-drug resistant P.falciparum is a major obstacle to malaria control and is highlighted by the abandonment of chloroquine (CQ) as a first-line treatment of P.falciparum infections worldwide. Chloroquine resistance (CQR) is associated primarily with mutations in the transmembrane digestive vacuole protein, PfCRT. However, CQR P.falciparum parasites harboring the same mutant pfcrt allele vary in their CQ response, suggesting the CQ response is multigenic in nature. No gene outside of pfcrt is completely associated with CQR. Thus, …

Localization Of Phosphatidylinositol 4,5-Bisphosphate To Lipid Rafts And Uroids In The Human Protozoan Parasite Entamoeba Histolytica, Amrita B. Koushik, Rhonda R. Powell, Lesly A. Temesvari

Publications

Entamoeba histolytica is an intestinal protozoan parasite and is the causative agent of amoebiasis. During invasive infection, highly motile amoebae destroy the colonic epithelium, enter the blood circulation, and disseminate to other organs such as liver, causing liver abscess. Motility is a key factor in E. histolytica pathogenesis, and this process relies on a dynamic actomyosin cytoskeleton. In other systems, phosphatidylinositol 4,5-bisphosphate [PI(4,5)P₂] is known to regulate a wide variety of cellular functions, including signal transduction, actin remodeling, and cell motility. Little is known about the role of PI(4,5)P₂ in E. histolytica pathogenicity. In this study, we …

Escherichia Coli Strain Diversity In Humans: Effects Of Sampling Effort And Methodology, Emily R. Neal

Master's Theses

Studies investigating Escherichia coli strain diversity and demographics in human hosts are frequently inconsistent regarding sampling effort and methodology while current strain typing methods are often expensive or laborious. To rectify these inconsistencies, sampling effort was investigated by comparing the diversity of 15-isolate collections to 100-isolate collections from 3 human subjects. Temporal variation in E. coli strain diversity was also studied by collecting 15 isolates once every 6 months. Additionally, strain identification and diversity collected by different sampling methods (fecal swabs vs. anal swabs collected at different times around defecation) were compared to identify any inherent biases in sampling method. …

Analysis Of The Chondroitinase Operon Of Flavobacterium Columnare, Erin L. Sorlien

Senior Honors Projects

Analysis of the chondroitinase operon of Flavobacterium columnare

Erin Sorlien

Major

Cell and Molecular Biology, Chemistry

Advisor

Dr. David R. Nelson

Date

May 2, 2013

Keywords

Flavobacterium columnare, columnaris disease, chondroitin AC lyase, complementation, csl operon

Abstract
Flavobacterium columnare, an opportunistic bacterial pathogen of fish, is the causative agent of columnaris disease (CD). The bacterium is a Gram-negative rod that exhibits gliding motility and avidly forms biofilms. CD affects both wild and cultured freshwater fish, and continues to cause large economic losses to the fish farming industry. According to an investigation conducted by the National Animal Health Monitoring System, CD …

Development Of A Predictive Modeling System For Validation Of The Cumulative Mirobial Inactivation Of The Salmonellae In Pepperoni Utilizing A Non-Pathogenic Surrogate Microorganism (Enterococcus Faecalis), Scott Donald Stillwell

Graduate Theses and Dissertations

Salmonellosis is the most frequently occurring bacterial foodborne illness in the United States and the human case rate has not improved for the past two decades. The federal agency responsible for oversight of meat and poultry processors has announced the intent to extend existing pathogen reduction performance standards for Salmonella spp. to cover all classes of products including fermented sausages that are currently produced under HACCP plans that are validated for control of Escherichia coli O157:H7. The proposed regulatory modifications will require processors to revalidate HACCP plan controls to achieve either a 6.5 or a 7.0 log10 inactivation of the …

Interaction Of Bacillus Anthracis Exosporium Protein Bcla With Complement Factor H And Spore Persistence In The Lung, Sarah A. Jenkins

Dissertations and Theses (Open Access)

Anthrax outbreaks in the United States and Europe and its potential use as a bioweapon have made Bacillus anthracis an interest of study. Anthrax infections are caused by the entry of B. anthracis spores into the host via the respiratory system, the gastrointestinal tract, cuts or wounds in the skin, and injection. Among these four forms, inhalational anthrax has the highest lethality rate and persistence of spores in the lungs of animals following pulmonary exposure has been noted for decades. However, details or mechanisms of spore persistence were not known. In this study, we investigated spore persistence in a mouse …

The Presence Of Methicillin Resistant Staphylococcus Aureus (Mrsa) On Environmental Surfaces In Healthcare Facilities Pre- And Post-Cleaning, Aaron Thomas Hunt

UNLV Theses, Dissertations, Professional Papers, and Capstones

The emergence of antibiotic resistant bacteria is a serious public health issue affecting millions of people. Methicillin-resistant Staphylococcus aureus(MRSA) is a leading cause of healthcare acquired infections today. Research has shown that patients infected or colonized with MRSA shed the bacteria into the environment, where the bacteria can survive for long periods of time and become potential sources of infection. Currently, infection prevention efforts focus on active surveillance, hand hygiene, personal protective equipment use and antimicrobial stewardship, with less attention given to environmental cleaning. Nevertheless, environmental cleaning is essential to remove infectious agents from environmental surfaces and prevent transmission. The …

A Mathematical Model For Antibiotic Resistance In A Hospital Setting With A Varying Population, Edward H. Snyder

Electronic Theses and Dissertations

Antibiotic-resistant bacteria(ARB) is causing increased health risk and cost to society. Mathematical models have been developed to study the transmission of resistant bacteria and the efficacy of preventive measures to slow its spread within a hospital setting. The majority of these models have assumed a constant total hospital population with the admission and discharge rates being equal throughout the duration. But a typical hospital population varies from day to day and season to season. In this thesis, we apply variable admission and discharge daily rates to existing deterministic and stochastic models which examine the transmission of single and dual resistant …

Analysis Of The Interaction Of Francisella Tularensis Lvs And Legionella Pneumophila Biofilms With Components Of The Aquatic Environment, Uma Mahajan

All Dissertations

Biofilms are complex communities of organisms enclosed in a matrix (EPS) composed of polysaccharides, proteins and DNA. Biofilms are the base of the aquatic ecosystem and interact with the biotic as well as the abiotic components in the environment. Biofilms interact with biotic components of the environment such as protozoa and aquatic invertebrates. In this project, the biotic interactions of Francisella tularensis LVS biofilms are studied in relation to the mosquito larvae of Culex quinquefasciatus. F. tularensis is the causative agent of tularemia and is transmitted by ticks, deer flies, and mosquitoes. Mosquitoes are believed to play a role in …

Neuropathogenic Escherichia Coli K1 Does Not Exhibit Proteolytic Activities To Exert Its Pathogenicity, Junaid Iqbal, Mehak Rajan, Ruqaiyyah Siddiqu, Naveed Ahmed Khan

Department of Biological & Biomedical Sciences

Background: Proteases are well-known virulence factors that promote survival, pathogenesis and immune evasion of many pathogens. Several lines of evidence suggest that the blood-brain barrier permeability is a prerequisite in microbial invasion of the central nervous system. Because proteases are frequently associated with vascular permeability by targeting junctional proteins, here it is hypothesized that neuropathogenic Escherichia coli K1 exhibit proteolytic activities to exert its pathogenicity.
Methods: Zymographic assays were performed using collagen and gelatin as substrates. The lysates of whole E. coli K1 strain E44, or E. coli K-12 strain HB101 were tested for proteolytic activities. The conditioned media were …

Characterization Of Human Gut Microbiota Dynamics Using Model Communities In Gnotobiotic Mice, Nathaniel Patrick Mcnulty

All Theses and Dissertations (ETDs)

The human gut is colonized by a diverse array of microbes, collectively referred to as the microbiota. The microbiota's complexity poses significant challenges in characterizing the rules dictating its assembly, inferring the functional roles of its component species, and understanding how communities sense and respond to changes in their habitat. We developed defined, representative model communities comprised of sequenced human gut bacteria that could be characterized in a highly controlled manner in gnotobiotic mice, plus a suite of scalable molecular tools for assaying community properties. These tools were first used to evaluate how the microbiota is impacted by probiotic bacterial …

The Influence Of Diet On The Mammalian Gut Microbiome, Brian David Muegge

All Theses and Dissertations (ETDs)

The mammalian gut is residence to a large microbial community whose collective set of millions of genes: microbiome) encodes a vast array of functions, including many that process dietary components. Few tools are available to change the microbiome's properties to promote host health because the factors governing community assembly and operation are poorly understood. My thesis focused on the impact of one factor, host diet.

I used a variety of experimental and computational methods to perform a comparative metagenomic study of the fecal communities of 39 diverse mammals to assess microbiome variation. These animals included herbivores, omnivores and carnivores representing …

Enrollment In Yfv Vaccine Trial: An Evaluation Of Recruitment Outcomes Associated With A Randomized Controlled Double-Blind Trial Of A Live Attenuated Yellow Fever Vaccine, Paula M. Frew, Eve T. Shapiro, Lu Lu, Srilatha Edupuganti, Harry L. Keyserling, Mark J. Mulligan

Environmental & Global Health Faculty Research

This investigation evaluated several factors associated with diverse participant enrollment of a clinical trial assessing safety, immunogenicity, and comparative viremia associated with administration of 17-D live, attenuated yellow fever vaccine given alone or in combination with human immune globulin. We obtained baseline participant information (e.g., sociodemographic, medical) and followed recruitment outcomes from 2005 to 2007. Of 355 potential Yellow Fever vaccine study participants, 231 cases were analyzed. Strong interest in study participation was observed among racial and ethnically diverse persons with 36.34% eligible following initial study screening, resulting in 18.75% enrollment. The percentage of white participants increased from 63.66% (prescreened …

Novel Neutralizing Antibody Assays For Recombinant Human Hookworm Na-Gst-1 Vaccine, Xi Chen, Brian Keegan, Peter J. Hotez, Jeffrey M. Bethony, Amar R. Jariwala

GW Research Days 2013

BACKGROUND

Necator Americanus, a human hookworm causes approximately 85% of the global hookworm infections. Hookworm ingest hemoglobin containing erythrocytes. Hemoglobin is further digested to Heme and Globin by hookworm's gut enzymes. Iron-containing Heme is a potent enzyme inhibitor and generates toxic reactive oxygen species which is toxic to hookworms. Hookworm's gut enzyme Na-GST-1 (Necator Americanus Glutathione S-Transferase-1) has been hypothesized to detoxify Heme. Na-GST-1 adjuvanted with Alhydrogel® is a new vaccine which is currently under clinical development. Na-GST-1 has two active sites, the ligand binding or Heme detoxification site (H-site) and the catalytic active glutathione binding …

Antioxidant Treatment Regulates The Humoral Immune Response During Acute Viral Infection, Katie E. Crump, P. Kent Langston, Sujana Rajkarnikar, Jason M. Grayson

Biology Faculty Articles

Generation of reactive oxygen intermediates (ROI) following antigen receptor ligation is critical to promote cellular responses. However, the effect of antioxidant treatment on humoral immunity during a viral infection was unknown. Mice were infected with lymphocytic choriomeningitis virus (LCMV) and treated with Mn(III)tetrakis(4-benzoic acid)porphyrin chloride (MnTBAP), a superoxide dismutase mimetic, from days 0 to 8 postinfection. On day 8, at the peak of the splenic response in vehicle-treated mice, virus-specific IgM and IgG antibody-secreting cells (ASC) were decreased 22- and 457-fold in MnTBAP-treated animals. By day 38, LCMV-specific IgG ASC were decreased 5-fold in the bone marrow of drug-treated mice, …

Progress Realized: Trends In Hiv-1 Viral Load And Cd4 Cell Count In A Tertiary-Care Center From 1999 Through 2011, Howard B. Gale, Manuel D. Rodriguez, Heather J. Hoffman, Debra A. Benator, Fred M. Gordin, Ann M. Labriola, Virginia L. Kan

Epidemiology Faculty Publications

Abstract

Accumulating evidence suggests that alterations in immune function may be important in the etiology of papillary thyroid cancer (PTC). To identify genetic markers in immune-related pathways, we evaluated 3,985 tag single nucleotide polymorphisms (SNPs) in 230 candidate gene regions (adhesion-extravasation-migration, arachidonic acid metabolism/eicosanoid signaling, complement and coagulation cascade, cytokine signaling, innate pathogen detection and antimicrobials, leukocyte signaling, TNF/NF-kB pathway or other) in a case-control study of 344 PTC cases and 452 controls. We used logistic regression models to estimate odds ratios (OR) and calculate one degree of freedom P values of linear trend (PSNP-trend) for the association …

Lysine Biosynthesis In Bacteria: A Metallodesuccinylase As A Potential Antimicrobial Target, Danuta M. Gillner, Daniel P. Becker Ph.D., Richard C. Holz

Chemistry: Faculty Publications and Other Works

In this review, we summarize the recent literature on dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase (DapE) enzymes, with an emphasis on structure–function studies that provide insight into the catalytic mechanism. Crystallographic data have also provided insight into residues that might be involved in substrate and hence inhibitor recognition and binding. These data have led to the design and synthesis of several new DapE inhibitors, which are described along with what is known about how inhibitors interact with the active site of DapE enzymes, including the efficacy of a moderately strong DapE inhibitor.