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Analysis Of Bacterial Loads In Houston Indoor Air., Zeest Hanif Hanif

Theses (2016-Present)

House dust is a complex matrix containing organic and inorganic content with a good percentage of microorganisms. Microorganism’s growth and survival in dust depends on available moisture level. Microbial origin in dust depends on sources other than dust. On average people spend approximately 90% of their time in indoor environment. Therefore, they are continuously exposed to microbes in dust. Based on the size and volume of dust particles the microbes get access to human lungs via airways. Based on previous research; culture dependent studies indicate that Penicillium, Aspergillus, Cladosporium are in abundance is house dust along with 20 other fungal …

The Long-Term Persistence And Tissue Tropism Of Brazilian Zika Virus In Monodelphis Domestica, Marisol Morales

Theses and Dissertations

Zika virus (ZIKV) rose as a major public health concern due to the congenital abnormalities of infants born to infected mothers during the 2015 Latin American outbreak. While animal models such as transgenic mice and nonhuman primates are used to study ZIKV pathogenesis, they display various limitations. Additionally, the persistence and tissue distribution of long-term ZIKV infection remains unknown. We describe the laboratory opossum, Monodelphis domestica, as a potential new model for ZIKV pathogenesis research to address these issues. We utilized immunohistochemistry, RT-PCR, and ELISA to show that: infant animals inoculated intracerebrally were susceptible to infection, ZIKV infection persisted …

Structural And Functional Insights Into Alphavirus-Host Interactions, Arthur S. Kim

Arts & Sciences Graduate Student Theses and Dissertations

Alphaviruses are arthropod-transmitted positive sense, single-stranded RNA viruses of the Togaviridae family that cause explosive, global outbreaks with significant morbidity. These viruses are classified into two groups based on genetic relatedness and clinical manifestations. Arthritogenic alphaviruses include chikungunya (CHIKV), Mayaro (MAYV), Ross River (RRV), O’nyong’nyong (ONNV) and generally cause acute and chronic musculoskeletal disease. To date, CHIKV has caused >1.8 million cases in over 40 countries. Encephalitic alphaviruses, including Eastern (EEEV), Venezuelan (VEEV), and Western (WEEV) equine encephalitis viruses, infect the central nervous system and result in encephalitic sequelae. In 2019, outbreaks of EEEV in the United States have resulted …

Spatial Ecology And Resource Selection Of Bighorn Sheep (Ovis Canadensis) Ewes In A Prairie Badlands Population, Erin Wood

School of Natural Resources: Dissertations, Theses, and Student Research

The basic spatial ecology and habitat relationships of female bighorn sheep in Nebraska are poorly understood. Establishing seasonal patterns of space use and resource selection for this population at the margin of their historical and current range addresses a key knowledge gap and provides important baseline information for ongoing conservation efforts in Nebraska. We deployed GPS radio-collars on 56 adult ewes in western Nebraska to quantify seasonal space use, movements, and resource selection of ewes. To investigate spatial ecology, we quantified movements of ewes and the factors that influence home range size, seasonal use, and spatial stability across seasons. Home …

Discovery Of Exosomes From Tick Saliva And Salivary Glands Reveals Therapeutic Roles For Cxcl12 And Il-8 In Wound Healing At The Tick–Human Skin Interface, Wenshuo Zhou, Faizan Tahir, Joseph Che Yen Wang, Michael Woodson, Michael B. Sherman, Shahid Karim, Girish Neelakanta, Hameeda Sultana

Faculty Publications

© Copyright © 2020 Zhou, Tahir, Wang, Woodson, Sherman, Karim, Neelakanta and Sultana.Ticks secrete various anti-coagulatory, anti-vasoconstrictory, anti-inflammatory, and anti-platelet aggregation factors in their saliva at the bite site during feeding to evade host immunological surveillance and responses. For the first time, we report successful isolation of exosomes (small membrane-bound extracellular signaling vesicles) from saliva and salivary glands of partially fed or unfed ixodid ticks. Our data showed a novel role of these in vivo exosomes in the inhibition of wound healing via downregulation of C-X-C motif chemokine ligand 12 (CXCL12) and upregulation of interleukin-8 (IL-8). Cryo-electron microscopy (cryo-EM) analysis …

Can A Sex Bias Be A Good Thing: Modeling Spontaneous Clearance And Sexual Susceptibility In Hcv, Tanner K. Shea

Biology ETDs

Hepatitis C virus (HCV) is a global epidemic that has been increasing for decades, afflicting millions of people who inject drugs (PWID) and is a major cause of liver disease. With novel direct-acting antivirals, treating the virus has become possible yet elimination remains out of reach. Prior research has shown significant differences in disease progression between men and women. These differences can lead to variation in incidence or what proportion of infections progress to chronic infections. We develop a mathematical model that accounts for potential differences between the sexes to evaluate the impacts on HCV transmission. We find that susceptibility …

Disruption Of Pyoverdine Synthesis In Pseudomonas Aeruginosa Through Periodic Disturbance Of Biofilm Structure, Rebecca J. Quinn

All HCAS Student Capstones, Theses, and Dissertations

Infections due to bacteria were once easily treated using antibiotics. However, the effective shelf life of antibiotics is diminishing due to the rise and spread of antibiotic resistant bacteria. Accordingly, novel approaches to treating infections are required. Pseudomonas aeruginosa is a multi-drug resistant, biofilm forming opportunistic pathogen. A determinant of P. aeruginosa’s pathogenicity is pyoverdine, a siderophore that is used to sequester iron from the environment. After being produced by a bacterium, pyoverdine is secreted into the environment where it complexes with iron. The pyoverdine-iron complex is then returned to the bacteria through diffusion, where it drives the synthesis of …

Comparative Whole-Genome And Phenotype Analyses Of Virulence Factors And Lethality In Nematode Challenge Assay Among Aeromonas Isolates, Pyeongsug Kim

Master of Science in Integrative Biology Theses

Aeromonads are bacteria found globally in fresh and brackish waters, with some species causing water-borne diseases vertebrate hosts such as diarrhea and wound-infections in humans and motile Aeromonas septicemia in fish. Although many virulence factors have been described, determining which factors are most important in pathogenesis is ongoing. To examine this further, the genomes of five Aeromonas strains isolated from various animals were sequenced and annotated in this study. Each isolate was further characterized using comparative genomic analyses and testing for production of selected virulence factors. Although previously identified as Aeromonas hydrophila, modern genotypic approaches including multilocus sequence typing …

A Study On Ecological Distribution Of And Selected Gene Expression In Amblyomma Americanum: An Insight Into The Alpha-Galactose Allergy Caused By Tick Bites, Leah Cuthill

Electronic Theses & Dissertations

Ticks transmit a wide variety of pathogens including viruses, bacteria, protozoa, and helminthes to vertebrates. Their life cycle depends on blood meals from various hosts as well as on environmental conditions such as the temperature and habitat type. A newly recognized allergic disease has been identified and is characterized by a delayed reaction following the consumption of some mammalian meats. The allergy often results in life threatening reactions such as anaphylaxis, hives, and breathing problems 3-6 hours after the consumption of mammalian meat. Not everyone develops the allergy when they are bitten by a lone star tick, and the cause …

Vertical Transmission And Venereal Transmission Of Zika Virus In A Population Of South Texas Aedes Aegypti, Jeremy Marshall

Theses and Dissertations

Zika virus has become a greater global public health concern from the occurrence of outbreaks in 2007 and its expansion to the Americas in 2015. The presence of Aedes aegypti in the Lower Rio Grande Valley and evidence of local transmission of Zika in Brownsville, Texas provides a need to research transmission dynamics of local populations. In these experiments, a locally acquired, laboratory colony of Aedes aegypti mosquitoes were infected with a blood meal featuring a Mexican isolate of Zika virus to display vector competency, vertical transmission, venereal transmission. Here, we infected 39 females, with 34 of them displaying evidence …

The Role Of Chromatin Remodeling Protein And Transcriptional Repressor, Ing4, In Hematopoiesis Regulation, Melanie Rodriguez

Theses and Dissertations

The hematopoietic compartment is tasked with the establishment and maintenance of the entire blood program. Key to this process are hematopoietic stem cells (HSCs), which possess the unique ability to self-renew and differentiate to replenish blood cells throughout an organism’s lifetime. In a screen for epigenetic regulators of hematopoiesis in zebrafish, we identified chromatin remodeling protein and transcription repressor, Ing4, as a requirement for hematopoietic stem and progenitor cell (HSPC) specification. Ing4, a member of the inhibitor of growth (ING) family, is a subunit of the HB01-JADE-hEAF6 histone acetyltransferase complex responsible for most nucleosomal histone H4 acetylation in eukaryotes. Ing4 …

Macronutrient Intake And Simulated Infection Threat Independently Affect Life History Traits Of Male Decorated Crickets, Kristin Duffield, Kylie J. Hampton, James Rapkin, John Hunt, Scott K. Sakaluk, Ben M. Sadd, Thomas M. Houslay

Faculty Publications – Biological Sciences

Nutritional geometry has advanced our understanding of how macronutrients (e.g.,proteins and carbohydrates) influence the expression of life history traits and theircorresponding trade-offs. For example, recent work has revealed that reproduc-tion and immune function in male decorated crickets are optimized at very differentprotein:carbohydrate (P:C) dietary ratios. However, it is unclear how an individual'smacronutrient intake interacts with its perceived infection status to determine in-vestment in reproduction or other key life history traits. Here, we employed a fullyfactorial design in which calling effort and immune function were quantified formale crickets fed either diets previously demonstrated to maximize calling effort(P:C = 1:8) or immune …

Potential Effects Of Climate Change On The Geographic Distribution Of The Endangered Plant Species Manihot Walkerae, Gisel Garza, Armida Rivera, Crystian Sadel Venegas Barrera, Jose Guadalupe Martinez-Avalos, Jon Dale, Teresa Patricia Feria-Arroyo

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Walker’s Manihot, Manihot walkerae, is an endangered plant that is endemic to the Tamaulipan thornscrub ecoregion of extreme southern Texas and northeastern Mexico. M. walkerae populations are highly fragmented and are found on both protected public lands and private property. Habitat loss and competition by invasive species are the most detrimental threats for M. walkerae; however, the effect of climate change on M. walkerae’s geographic distribution remains unexplored and could result in further range restrictions. Our objectives are to evaluate the potential effects of climate change on the distribution of M. walkerae and assess the usefulness of natural protected areas …

Introducing Lu-1, A Novel Lactobacillus Jensenii Phage Abundant In The Urogenital Tract, Taylor Miller-Ensminger, Rita Mormando, Laura Maskeri, Jason W. Shapiro, Alan J. Wolfe, Catherine Putonti

Bioinformatics Faculty Publications

Bacteriophages (phages) play a key role in shaping microbial communities, including those of the human body. Phages are abundant members of the urogenital tract, most often persisting through the lysogenic life cycle as prophages integrated within the genomes of their bacterial hosts. While numerous studies of the urogenital microbiota have focused on the most abundant bacterial member of this niche–Lactobacillus species–very little is known about Lactobacillus phages. Focusing on Lactobacillus jensenii strains from the urinary tract, we identified numerous prophages related to the previously characterized Lv-1 phage from a vaginal L. jensenii strain. Furthermore, we identified a new L. jensenii …

Editorial Board

Karbala International Journal of Modern Science

No abstract provided.

From Theory To Practice: Interdisciplinary Science In Undergraduate Education, Brie Tripp

Dissertations and Theses

Science has undergone a major transformation in the 20th and 21st centuries with new fields emerging at the intersection of disciplines, such as bioethics, bioinformatics, and chemical ecology. Yet, opportunities to engage with interdisciplinary science, and the skills needed to work in these fields, are largely absent from undergraduate biology classrooms. As a consequence, students are potentially deprived of opportunities to think interdisciplinarily and engage with real-world issues that often necessitate interdisciplinary efforts. To be informed citizens in society and forward-thinking scientists in the workforce, undergraduate students will undoubtedly benefit from exposure to these interdisciplinary science experiences.

Given these considerations, …

The Genesis Of Sars-Cov-2 Virus And The Origin Of The Covid-19 Pandemic, Alan L. Gillen

Faculty Publications and Presentations

The current outbreak of the 2019 novel coronavirus (SARS-CoV-2, fig. 1), causing a respiratory-tract illness, first started in Wuhan, China, and has been escalating worldwide. The official disease name became known as COVID-19 in mid-spring 2020. It shares some characteristics of the SARS virus of 2002–3. Early on, with many cases in Wuhan, China, it was reported that the outbreak had some association with animal markets, which indicated that there was animal-to-person transmission. Like SARS-CoV-1, the suspected animal source of the virus is bats. We have not seen this virus before, and our bodies were not ready for this, nor …

First International External Quality Assessment Scheme Of Nucleic Acid Amplification Tests For The Detection Of Schistosoma And Soil-Transmitted Helminths, Including Strongyloides: A Pilot Study, Piet Cools, Lisette Van Lieshout, Rob Koelewijn, David Addiss, Sitara S.R. Ajjampur, Mio Ayana, Richard S. Bradbury, Jason L. Cantera, Daniel Dana, Kerstin Fischer, Rubina Imtiaz, Joyce Kabagenyi, James Lok, James Mccarthy, Rojelio Mejia, Zeleke Mekonnen, Sammy M. Njenga, Nurulhasanah Othman, Hongguang Shao, Rebecca Traub, Marjan Van Esbroeck, Jozef Vercruysse, Johnny Vlaminck, Steven A. Williams, Jaco J. Verweij, Jaap J. Van Hellemond, Bruno Levecke

Biological Sciences: Faculty Publications

Background Nucleic acid amplification tests (NAATs) are increasingly being used as diagnostic tools for soil-transmitted helminths (STHs; Ascaris lumbricoides, Trichuris trichiura, Necator ameri-canus, Ancylostoma duodenale and A. ceylanicum), Strongyloides stercoralis and Schisto-soma in human stool. Currently, there is a large diversity of NAATs being applied, but an external quality assessment scheme (EQAS) for these diagnostics is lacking. An EQAS involves a blinded process where test results reported by a laboratory are compared to those reported by reference or expert laboratories, allowing for an objective assessment of the diagnostic performance of a laboratory. In the current study, we piloted an international …

Dynamical Behavior Of A Malaria Relapse Model With Insecticide Treated Nets (Itns) As Protection Measure, Reuben I. Gweryina, Anande R. Kimbir

Applications and Applied Mathematics: An International Journal (AAM)

Malaria is a tropical disease which is mainly spread by plasmodium falciparum which has been the principal enemy to the existence of mankind till date. In this paper a version of a malaria model incorporating the use of treated mosquito nets as a disease control strategy is proposed and then transformed into proportions, so as to assess the global impact of ITNs on the prevalence of malaria. Constructing a Lyapunov function using matrix-theoretic approach, a malaria-free equilibrium state is obtained, which is globally asymptotically stable if the control reproduction number, 𝑅_𝑚<1. This means that malaria can be controlled or eradicated under such a threshold quantity, 𝑅𝑚. On the other hand, a malaria-persistence equilibrium state exists which is globally stable when 𝑅_𝑚>1, using geometric theoretic method with Lozoskii …

Discovery Of A Reproducing Wild Population Of The Swamp Eel Amphipnous Cuchia (Hamilton, 1822) In North America., F. Jordan, L. G. Nico, Kristal Alissa Huggins, Peter J. Martinat, D. A. Martinez, V. L. Rodrigues

Faculty and Staff Publications

We report discovery of an established population of the Asian swamp eel Amphipnous cuchia (Hamilton, 1822) in Bayou St. John, an urban waterway in New Orleans, Louisiana, USA. This fish, commonly referred to as cuchia (kuchia), is a member of the family Synbranchidae and is native to southern and southeastern Asia. Recently-used synonyms include Monopterus cuchia and Ophichthys cuchia. We collected both adult and young-of-year cuchia from dense mats of littoral vegetation at several locations in Bayou St. John. Presence of multiple age and size classes is the first documented evidence of reproduction of this species outside of its native …

Phenotypic Analysis Of S. Aureus Strains From University Student Health Centers And Environmental Controls, Antonio Teixeira

Honors Theses

Methicillin-resistant Staphylococcus aureus (MRSA) is a group of pathogenic bacterial strains resistant to a class of antibiotics that is a major cause for concern in health care systems. There is a lack of study in whether health care centers are reservoirs for these bacteria, especially within developed countries. Five environmental swab samples were collected from five different university health care centers across the region, and 16 swab samples from a general university environment. Any isolated bacterial strains collected underwent five biochemical tests (mannitol fermentation, DNase activity, oxidase activity, catalase activity, and coagulase activity) to preliminarily identify S. aureus bacteria. 24% …

Lymphatic Filariasis: Host And Parasite Factors And The Pathogenesis Of Systemic Adverse Events Following Treatment, Britt Juul Andersen

Arts & Sciences Graduate Student Theses and Dissertations

Lymphatic filariasis (LF) is a neglected tropical disease caused by the nematode parasites Wuchereria bancrofti, Brugia malayi and B. timori. The primary tool used by the Global Program to Eliminate LF is mass drug administration (MDA), and some 500 million people take the medications each year. Mild to moderate adverse events (AEs) are common after LF treatment, and these pose a major challenge for the LF elimination program. To better understand the pathogenesis of AEs, we studied patients from LF treatment trials in Côte d’Ivoire and Papua New Guinea, where plasma and leucocytes were collected pre and post-treatment and subjects …

Development Of An In Vitro Culture System For Cryptosporidium Parvum, Georgia Wilke

Arts & Sciences Graduate Student Theses and Dissertations

Cryptosporidium is a genus of protozoan parasites that causes diarrheal disease in humans and other animals. There are two major species that cause disease in humans: C. parvum, which infects both humans and animals, and C. hominis, which primarily infects humans. A recent study investigating the etiologies of pediatric diarrheal illness in Africa and South Asia found that Cryptosporidium is the 2nd most prevalent cause of diarrhea in infants and may be a contributing factor to chronic malnutrition. This discovery has led to renewed interest in studying this parasite and a reexamination of the barriers to studying Cryptosporidium. The main …

Conformational Basis And Small Molecule Antagonists Of E. Coli Adhesion To The Urinary Tract, Vasilios Kalas

Arts & Sciences Graduate Student Theses and Dissertations

Urinary tract infections (UTIs) are one of the most prevalent infections, afflicting 15 million women per year in the United States with annual healthcare costs exceeding $2-3 billion. Uropathogenic Escherichia coli (UPEC) are the main etiological agent of UTIs and employ numerous virulence factors for host colonization. The most common adhesive mechanism by which UPEC mediate host-pathogen interactions is the chaperone-usher pathway (CUP), which is responsible for the assembly of proteinaceous surface appendages termed pili. Generally, CUP pili function in adherence or invasion of host tissues and in biofilm formation on medical devices and body habitats. CUP pili are highly …

In Vivo Mechanisms Of Natural Killer Cell Tolerance, Michael Bern

Arts & Sciences Graduate Student Theses and Dissertations

Natural killer (NK) cells are cytotoxic innate immune cells that provide protection from pathogens and tumors. To carry out these functions, NK cells must distinguish between healthy and unhealthy self-cells. Inability to recognize stressed cells would lead to a failure of NK-cell immunity whereas inability to identify healthy cells could lead to NK-cell autoimmunity. It remains unclear, however, how NK cells are able to distinguish healthy and unhealthy self-cells with a limited repertoire of germline-encoded receptors. The "missing-self" hypothesis proposes that NK cells identify stressed cells by their reduced expression of MHC class I (MHC-I) that is almost ubiquitously expressed …

Identifying Determinants Of Target Specificity In Two Related Bacterial Peptide Toxins, Andrew D. Holmes

Honors Thesis

Toxin-antitoxin (TA) systems were originally identified as two-component systems ensuring the stable inheritance of plasmids in bacterial populations. Recently, they have been identified on bacterial chromosomes where their functions remain mostly undefined. The par locus of E. faecalis plasmid pAD1 (par_pAD1) was the first TA system defined in a Gram-positive bacterium and a homolog encoded on the E. faecalis chromosome (par_EF0409) was later described. Related loci numbering in the hundreds have been identified throughout Gram-positive bacteria based on homology to the toxin of the system, Fst, and similarities in genetic organization and regulation. Despite …

The Relationship Between Glucocorticoids And The Humoral Immune Response To Mycoplasma Gallisepticum Challenges In Eastern Bluebirds, Joshua Smith

Honors Theses

Numerous studies have examined relationships between adrenal glucocorticoids and the immune system’s ability to fight disease. The relationship can vary, with glucocorticoids having either stimulatory or inhibitory effects. The pathogenic bacterium Mycoplasma gallisepticum (MG) elicits an adaptive immune response in birds, in which B cells produce MG-specific antibodies to fight the infection and prevent reoccurrence. Previous research found that Eastern Bluebirds that produce the most antibodies in response to MG infection also have the highest glucocorticoid levels. This finding led to the current study investigating whether corticosterone, the primary glucocorticoid in birds, stimulates production of antibodies in response to immune …

Influences Of Anti-Bd Bacteria On Amphibians And Their Microbiomes, Emme L. Schmidt

Honors Thesis

The fungal pathogen Batrochochytrium dendrobatidis (Bd) has been threatening amphibian populations across the globe. Recent work has discovered that bacteria isolated from certain populations of amphibians protect hosts from this pathogen. This project focuses on the anti-fungal mechanisms of Serratia marcescens, a species of bacteria isolated from a Costa Rican frog that dramatically inhibited Bd in culture. Wild-type and recombinant S. marcescens was introduced to the microbiomes of a live amphibian host, Acris blanchardi (Blanchard’s Cricket Frog) and then challenged with Bd to examine the protective effects of this bacteria. The experiment includes recombinant S. marcescens with …

Presence Of Dirofilaria Immitis In Mosquitoes In Southeastern Georgia, Angelica C. Tumminello

Honors College Theses

Canine heartworm disease is caused by the filarial nematode Dirofilaria immitis, which is transmitted by at least 25 known species of mosquito vectors. This study sought to understand which species of mosquitoes are present in Bulloch County, Georgia, and which species are transmitting canine heartworm disease. This study also investigated whether particular canine demographics correlated with a greater risk of heartworm disease. Surveillance of mosquitoes was conducted in known heartworm-positive canine locations using traditional gravid trapping and vacuum sampling. Mosquito samples were frozen until deemed inactive, then identified by species and sex. The mosquitoes were then either dissected under …

Rapid Antibiotic Susceptibility Testing Platform For Direct Clinical Samples, Terrance Zhang

Honors Scholar Theses

Infectious diseases and septicemia are two of the major causes of death in the U.S., necessitating rapid treatment of septic patients with proper, efficacious antibiotics. Unfortunately, the emergence and spread of multidrug-resistant bacteria are continuously being aggravated by an abuse in antibiotic prescription at a clinical and agricultural level. It is known that antibiotic resistance evolves through the sequential accumulation of multiple mutations in bacteria, which is accentuated by prolonged exposure of bacteria to ineffective antibiotics when implementing traditional septicemia treatment. The goal of this project is to develop a novel, easy-to-use AST platform for rapid antimicrobial susceptibility profiling to …