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Mathematical Modeling Of Potassium Modulated Viral Infection, Zaira Elizabeth Mather 2022 The University of Texas at El Paso

Mathematical Modeling Of Potassium Modulated Viral Infection, Zaira Elizabeth Mather

Open Access Theses & Dissertations

In recent years, there is a growing interest in the investigation of using potassium to treat virus infections. In the region of infection, there is a biological observation of extracel- lular potassium level being typically very low whereas the intracellular potassium levels are much higher. There are numerous biological studies showing that elevated potassium levels in the extracellular membrane tends to block virus infections. A recent effort in this direction is a collaborative research conducted by mathematicians and biologists from the University of Texas at El Paso, New Mexico State University, and the University of New Mexico, where we develop …


Alterations Of The Gut Mycobiome In Patients With Ms - A Bioinformatic Approach, Saumya Shah 2022 University of Connecticut

Alterations Of The Gut Mycobiome In Patients With Ms - A Bioinformatic Approach, Saumya Shah

Honors Scholar Theses

The mycobiome is the fungal component of the gut microbiome and is implicated in several autoimmune diseases. However, its role in multiple sclerosis (MS) has not been studied. We performed descriptive and formal statistical tests using the R language to characterize the gut mycobiome in people with MS (pwMS) and healthy controls. We found that the microbiome composition of multiple sclerosis patients is different from healthy people. The mycobiome had significantly higher alpha diversity and inter-subject variation in pwMS than controls. Additionally, Saccharomyces and Aspergillus were over-represented in pwMS. Different mycobiome profiles, defined as mycotypes, were associated with different bacterial …


Roles Of Small Rnas And Paralogous Proteins In Bacillus Anthracis Virulence Gene Regulation, Ileana Corsi 2022 The Texas Medical Center Library

Roles Of Small Rnas And Paralogous Proteins In Bacillus Anthracis Virulence Gene Regulation, Ileana Corsi

Dissertations and Theses (Open Access)

Bacteria have evolved a myriad of regulatory mechanisms to control gene expression. One of the most common mechanisms is post-transcriptional control through the function of small regulatory RNAs (sRNAs). Small regulatory RNAs (sRNAs) are short transcripts that base-pair to mRNA targets or interact with regulatory proteins. sRNA function has been studied extensively in Gram-negative bacteria; comparatively less is known about sRNAs in Firmicutes. In this dissertation, I investigated two sRNAs encoded within the virulence plasmid pXO1 of Bacillus anthracis, the causative agent of anthrax. The sRNAs, named “XrrA and XrrB” (for p­XO1-encoded regulatory RNA) are abundant and highly stable …


Investigation Of Genomic Instability Induced By G-Quadruplexes In The Absence Of Functional To Poisomerase 1 In Yeast, Alexandra Berroyer 2022 The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences

Investigation Of Genomic Instability Induced By G-Quadruplexes In The Absence Of Functional To Poisomerase 1 In Yeast, Alexandra Berroyer

Dissertations and Theses (Open Access)

Topoisomerase 1 (Top1) is an enzyme that removes transcriptionally generated negative supercoils by binding and nicking DNA. Since transcription of guanine-rich DNA leads to the formation of G-quadruplex (G4) structures, Top1’s function likely suppresses G4-formation. In support of this, Top1 significantly reduces co-transcriptional G4 DNA-associated genomic instability at a model G4-motif in Saccharomyces cerevisiae. However, whether Top1 suppresses G4-formation on a genome-wide scale in yeast remains unexplored. Therefore, I aimed to uncover if deletion of Top1 enhances genome-wide G4-formation in S. cerevisiae. As an approach to quantify global G4-formation, I expressed the G4-specific antibody BG4 from a yeast …


The Effect Of Cognitive Status And Residency On Oral Health In Patients With Dementia, Nicole Stephens 2022 The Texas Medical Center Library

The Effect Of Cognitive Status And Residency On Oral Health In Patients With Dementia, Nicole Stephens

Dissertations and Theses (Open Access)

Poor oral health is a predictor of cognitive decline in elderly populations and has been shown to precede dementia. As cognitive decline progresses, patients are likely to move from the community into nursing facilities. We hypothesize that severity of dementia and residency type will impact the oral health of patients with dementia. Fifty-two participants of two dementia levels were recruited from the UTHealth Neurocognitive Disorders Center and two Houston-area nursing homes. A standardized oral health assessment, plaque index, and oral bacteria analysis determined participants’ oral health status. Further, data was collected on participants’ medical history, oral hygiene habits, dietary habits, …


Effects Of Continuous In Situ Low-Dose Ionizing Radiation On Microorganisms, Molly E. Wintenberg 2022 Clemson University

Effects Of Continuous In Situ Low-Dose Ionizing Radiation On Microorganisms, Molly E. Wintenberg

All Dissertations

Precise detection and monitoring of nuclear fuel cycle, enrichment, and weapon development activities are critical for supporting warfighter preparation in chemical, biological, radiological, nuclear, and explosives (CBRNE) operations, clandestine activities, and nuclear compliance. A biological sensing system could serve as an alternative to traditional detection methods by using organic material naturally present in the environment to discreetly detect residual trace nuclear material. Microorganisms provide an optimal platform for an alternative sensing system; however, their response to low levels of ionizing radiation is poorly characterized. Combining the power of next-generation sequencing and transcriptomic analysis, this dissertation takes an approach to obtain …


Mechanistic Insights On The Role Of Ambrisentan, An Endothelin Type-A Receptor Antagonist, In Breast Cancer, Ruba Saleem Lutfi Amer 2022 United Arab Emirates University

Mechanistic Insights On The Role Of Ambrisentan, An Endothelin Type-A Receptor Antagonist, In Breast Cancer, Ruba Saleem Lutfi Amer

Theses

The activation of the endothelin receptor type A (ETAR) by its ligand endothelin-1 (ET-1) is well known for its role in vasoconstriction. Interestingly, ET-1 and ETAR are over-expressed in various human tumours, including breast cancer. Several studies described the important role of ETAR in cancer progression and metastasis. The extensive network of interactions that exist between the ET-1 axis and other signalling pathways can trigger autocrine and paracrine signalling that modulates different tumorigenesis processes, such as cellular proliferation and survival, epithelial-to-mesenchymal transition (EMT) and chemoresistance. The main objective of this study was to investigate the antitumor effects of Ambrisentan, a …


Characterizing The Interaction Between Candida Albicans And Two Enterobacter Species, Abigail Cornett 2022 East Tennessee State University

Characterizing The Interaction Between Candida Albicans And Two Enterobacter Species, Abigail Cornett

Electronic Theses and Dissertations

Candida albicans is the most common human fungal pathogen. The relationship between C. albicans and Enterobacter bacteria have yet to be explored. The hypothesis of this study is that C. albicans and both E. aerogenes and E. cloacae have a positive relationship and work together to infect the host. In this study, the physical cell-to-cell interaction, molecular components of said interaction, and the impact of the interaction on a live organism were explored. Results indicate that Enterobacter adheres to C. albicans and inhibits growth with unidentified secreted molecules. Als1p has potential involvement in the attachment of E. cloacae to C. …


Time Course Investigation Of The Dermal Leukocyte Response To Lipoteichoic Acid In Chickens, Ian Gilbert 2022 University of Arkansas, Fayetteville

Time Course Investigation Of The Dermal Leukocyte Response To Lipoteichoic Acid In Chickens, Ian Gilbert

Animal Science Undergraduate Honors Theses

Lipoteichoic acid (LTA) is component of the cell wall of Gram-positive bacteria that stimulates inflammation during bacterial infection. However, few studies have investigated the in vivo immune response to LTA, and none of the in vivo studies done have been performed in birds. For this project, the pulp (a skin-derivative) of growing feathers (GFs) of chickens were used as a test site to investigate the in vivo effects of intradermally injected LTA. In Study 1, the pulp of 12 GFs of 11-week-old Light-brown Leghorn (LBL) males were injected with 10 μL of differing concentrations of LTA (0.1, 1.0, 10, 100 …


Describing Bacterial Mutagenic Hotspots And Signatures Along With The Factors That Drive Them, Carmen Vallin 2022 University of Nevada, Las Vegas

Describing Bacterial Mutagenic Hotspots And Signatures Along With The Factors That Drive Them, Carmen Vallin

UNLV Theses, Dissertations, Professional Papers, and Capstones

In my dissertation work, I investigated bacterial mutagenesis. I asked: where do mutations occur in the bacterial genome? What types of mutations occur? What factors promote or prevent mutations? And lastly, how do the answers to these questions change depending on the bacterial life cycle (When)? I used Bacillus subtilis, a Gram-positive bacterium belonging to the phylum Firmicutes, and Escherichia coli, a Gram-negative bacterium belonging to the phylum Proteobacteria, to answer these questions. B. subtilis and E. coli are model systems that have been used to gain insights into fundamental processes of mutations and evolution for nearly ~8 decades. Here, …


Diffusive Dynamics Of Biological Macromolecules In The Cytoplasm Of Live Bacteria, Asmaa Ali Sadoon 2022 University of Arkansas, Fayetteville

Diffusive Dynamics Of Biological Macromolecules In The Cytoplasm Of Live Bacteria, Asmaa Ali Sadoon

Graduate Theses and Dissertations

Bacteria are small organisms that play important roles in our bodies and in maintaining our surrounding environment. However, bacterial infections are considered as one of the health diseases that threatens the lives of humans. Resistance of bacteria to antibiotics has made treating bacterial infections more challenging. With the emergence of many developed optical techniques, it has become possible to study various biological mechanisms of molecules inside these small organisms with high resolution and precise localization. In this research, single particle tracking photoactivation localization microscopy (sptPALM) technique was used to investigate the dynamics of fluorescent histonelike nucleoid-structuring proteins (H-NS) in live …


Mycobacteriosis Of Striped Bass (Morone Saxatilis) In Virginia Tributaries Of The Chesapeake Bay, Joshua S. McGilly 2022 Old Dominion University

Mycobacteriosis Of Striped Bass (Morone Saxatilis) In Virginia Tributaries Of The Chesapeake Bay, Joshua S. Mcgilly

Biological Sciences Theses & Dissertations

Mycobacteriosis was first documented in Chesapeake Bay striped bass (Morone saxatilis) in 1997 after fish exhibited emaciation and skin lesions. Since it was first identified, studies of mycobacteriosis in the mainstem of the Chesapeake Bay (2003-2007) and the Rappahannock River (2005-2012) have shown high disease prevalence and disease-associated mortality. Until this study, no current prevalence data existed from the Rappahannock River, and no published prevalence data existed for the James River, leaving a gap in our understanding of this disease in major Chesapeake Bay tributaries. We began gathering mycobacteriosis prevalence data from an existing survey collecting striped bass …


Elevated Levels Of External Cysteine Inhibit Nitrogen Fixation By The Methanogenic Archaeon Methanosarcina Acetivorans, Regan Massey 2022 University of Arkansas, Fayetteville

Elevated Levels Of External Cysteine Inhibit Nitrogen Fixation By The Methanogenic Archaeon Methanosarcina Acetivorans, Regan Massey

Biological Sciences Undergraduate Honors Theses

Methanogens are nitrogen fixing and methane producing archaea that play a key role in the cycling of carbon and nitrogen on earth. The global carbon and nitrogen cycle is vital to all life which makes the methanogen a primary organism of study. Methanogens are the only archaea capable of fixing nitrogen, and in order to do so, methanogens use a vital enzyme called the nitrogenase which fixes dinitrogen (N2) to ammonia (NH3). Expanding our understanding on metabolic processes of methanogens allows us to understand their environmental impact and advance their use in biotechnological applications. Methanosarcina acetivorans is the model used …


Exploring Nitrogen Fixation In Methanosarcina Acetivorans, Rylee Cook 2022 University of Arkansas, Fayetteville

Exploring Nitrogen Fixation In Methanosarcina Acetivorans, Rylee Cook

Biological Sciences Undergraduate Honors Theses

As of 2016, the genomes of over sixty species of methanogenic archaea have been sequenced.4 Research on the genomes of methanogens such as M. acetivorans led to the characterization of numerous genes with unknown functions. Genes similar to those of nitrogenase have been shown to possess functions unrelated to nitrogen fixation, such as F430 biosynthesis genes. 5,6,7 My research focused on the uncharacterized gene clusters ma2032-33 and ma1631-33 (Figure 1). These genes have conserved nitrogenase domains: ma2032 has fused nifH and nifD domains, while ma2033 has a nifD domain. The ma1631-33 gene cluster contains two nitrogenase homologs and one iron …


The Microbiome Characterization And Comparison Of Loggerhead (Caretta Caretta) And Green (Chelonia Mydas) Sea Turtle Eggs In Broward County, Florida, Colleen McMaken 2022 Nova Southeastern University

The Microbiome Characterization And Comparison Of Loggerhead (Caretta Caretta) And Green (Chelonia Mydas) Sea Turtle Eggs In Broward County, Florida, Colleen Mcmaken

All HCAS Student Capstones, Theses, and Dissertations

All seven extant species of sea turtles are classified as threatened or endangered due to natural and anthropogenic impacts. Sea turtle conservation efforts are largely dedicated to ensuring healthy nesting activity. Hatching success of sea turtle eggs can be affected by several factors including the proliferation of pathogenic microbes. However, it is unclear as to which microbes have the most impact on hatching success and how they are transmitted into the eggs. The primary aims of this study characterized and compared the bacterial communities (microbiomes) from the i) cloaca of nesting sea turtles; ii) sand within and surrounding the nests …


Literature Review: Antibody Production In Mice In Response To Aspergillus Fumigatus Inhalation, Jenica Hancock, Courtney Folk 2022 Minnesota State University Moorhead

Literature Review: Antibody Production In Mice In Response To Aspergillus Fumigatus Inhalation, Jenica Hancock, Courtney Folk

Student Academic Conference

Aspergillus fumigatus is a commonly inhaled respiratory fungal pathogen and an allergen found in flooded indoor environments, household dust, soil, and plant matter. Inhalation of A. fumigatus poses a threat to weakened immune systems due to the potential of infection in the lungs or sinuses which can spread to other areas of the body. The mouse genome is 99% similar to the human genome, and therefore they serve effectively in modeling the effects of inhaled A. fumigatus. A comprehensive literature search of antibody production in mice in response to A. fumigatus inhalation was conducted utilizing PubMed and the search terms …


Diversity Of Bacteriophage In Burkholderia Species, Abigail Price 2022 Bowling Green State University

Diversity Of Bacteriophage In Burkholderia Species, Abigail Price

Honors Projects

Bacteriophages are viruses that infect and replicate within bacteria and offer the potential of a therapeutic alternative to chronic infections that do not respond to antibiotic-based therapies. B. vietnamiensis is one of a number of Burkholderia species involved with chronic drug resistant infections in the lungs of individuals with compromised respiratory systems, as found in those with chronic obstructive pulmonary disease and, most especially, are of particular significance in patients with cystic fibrosis. The diversity of the Burkholderia species is explored by using online databases and looking at bacteriophage or phage-encoding viruses found in B. vietnamiensis. The open reading frames …


Aeromonas Phage Research And The Public Health Impact Of Antibiotics In Aquaculture Workers, Madelyn Merchant 2022 Bowling Green State University

Aeromonas Phage Research And The Public Health Impact Of Antibiotics In Aquaculture Workers, Madelyn Merchant

Honors Projects

One of the most common fish diseases in aquaculture is Aeromonas infection. The most common way to treat this infection is through antibiotics. The bacteria in the fish can become antibiotic-resistant and perpetuate the disease. The diseases in fish create a huge financial loss and the industry loses $6 billion per year due to diseases in fish. An alternative to antibiotics is bacteriophage which causes less environmental degradation and is better for human gut flora. In aquaculture there have been examples of aquaculture workers becoming sick from the water in aquaculture ponds as well as from people eating the fish. …


Periodic Spatial Disturbances Alter The Expression Of Quorum Sensing Virulence Factors In Pseudomonas Aeruginosa, Laura García-Diéguez 2022 Nova Southeastern University

Periodic Spatial Disturbances Alter The Expression Of Quorum Sensing Virulence Factors In Pseudomonas Aeruginosa, Laura García-Diéguez

All HCAS Student Capstones, Theses, and Dissertations

Pseudomonas aeruginosa is an opportunistic pathogen associated with severe acute and chronic illnesses. Current antibiotic-based approaches fail to effectively treat P. aeruginosa infections due to the effectiveness and robustness of the quorum sensing signaling system (QS). Pathogenic bacteria, such as P. aeruginosa, employ this population density-dependent communication mechanism to confer antimicrobial resistance, propagate infection, and coordinate the expression of virulence factors, through the production and detection of autoinducing signaling molecules (AI). As such, there is a growing interest in developing novel non-antibiotic-based techniques to attenuate the pathogenicity of P. aeruginosa by disrupting the functionality of its QS system. Previous …


Antiviral Activity Of Olanexidine-Containing Hand Rub Against Human Noroviruses, Khalil Ettayebi, Wilhelm Salmen, Kaoru Imai, Akifumi Hagi, Frederick H Neill, Robert L Atmar, B V Venkataram Prasad, Mary K Estes 2022 The Texas Medical Center Library

Antiviral Activity Of Olanexidine-Containing Hand Rub Against Human Noroviruses, Khalil Ettayebi, Wilhelm Salmen, Kaoru Imai, Akifumi Hagi, Frederick H Neill, Robert L Atmar, B V Venkataram Prasad, Mary K Estes

Faculty, Staff and Students Publications

Human norovirus (HuNoV) is the leading cause of epidemic and sporadic acute gastroenteritis worldwide. HuNoV transmission occurs predominantly by direct person-to-person contact, and its health burden is associated with poor hand hygiene and a lack of effective antiseptics and disinfectants. Specific therapies and methods to prevent and control HuNoV spread previously were difficult to evaluate because of the lack of a cell culture system to propagate infectious virus. This barrier has been overcome with the successful cultivation of HuNoV in nontransformed human intestinal enteroids (HIEs). Here, we report using the HIE cultivation system to evaluate the virucidal efficacy of an …


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