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Full-Text Articles in Organisms

Analysis Of Single Cell Rna-Seq Data Revealed Interferon Gamma Signaling Alteration In Severe Covid Patients, Ahmed Elbaz May 2021

Analysis Of Single Cell Rna-Seq Data Revealed Interferon Gamma Signaling Alteration In Severe Covid Patients, Ahmed Elbaz

Theses and Dissertations

Background: SARS-COV2 virus detected in December 2019, and was considered a pandemic in March 2020 by the WHO. Symptoms range from asymptomatic to life threatening ones. Studying cell-cell interactions in patients' blood samples may lead to novel diagnosis and treatment approaches.

Aim: This study aims to analyze single-cell RNA sequencing data to identify differences in cell-cell communications between healthy and COVID patients and differentially expressed T-cells genes that contributed to immune system antiviral activity.

Materials and methods: Single-Cell RNA sequencing data from seven COVID patients and five healthy individuals were collected from (GEO accession GSE155673). Cell types were identified and …


Dendrimer-Based Antibiotics For The Treatment Of Bacterial Biofilm In Cystic Fibrosis (Cf), Younan Ma Jan 2021

Dendrimer-Based Antibiotics For The Treatment Of Bacterial Biofilm In Cystic Fibrosis (Cf), Younan Ma

Theses and Dissertations

Pseudomonas aeruginosa (PA) is the predominant pathogen in chronic lung infections of cystic fibrosis (CF) patients. The most important mechanism of adaptation of PA to host defense and antibiotic treatment is the formation of biofilms within the mucus layer covering the lung bronchi. The effectiveness of antibiotics such as aminoglycosides is significantly attenuated by their limited penetration through thick mucus and embedded biofilm matrix in patients’ lung. Inhaled tobramycin (Tobra), which is the most commonly used antibiotics in the treatment of PA infections for CF patients, is usually found to be in very high concentration in patients’ lung, and yet …


Detection And Quantification Of Bacterial Species Important To Mental And Physical Health, David G. Leonard Mar 2020

Detection And Quantification Of Bacterial Species Important To Mental And Physical Health, David G. Leonard

Theses and Dissertations

The human gut microbiome contains an abundance of microorganisms which could influence mental health as well as physical health. These microorganisms produce chemicals which affect the brain and the body in various ways. Probiotic bacteria and yeasts have been studied to determine effects they have on mice, rats, and humans to illustrate the importance these microorganisms on health. Studies have shown that adding beneficial microorganisms to the human diet can have positive effects on mental and physical health, to include lessening symptoms of depression and anxiety, lessen gastrointestinal inflammation, displacing pathogens, and improving immunomodulatory response. A quantitative way to identify …


Characterization Of The Gonococcal Calprotectin Zn-Acquisition System, Tdfh, And The Efficacy Of Metal Starvation For Treating Gonococcal Disease, Michael T. Kammerman Jan 2020

Characterization Of The Gonococcal Calprotectin Zn-Acquisition System, Tdfh, And The Efficacy Of Metal Starvation For Treating Gonococcal Disease, Michael T. Kammerman

Theses and Dissertations

Abstract

Characterization of the Gonococcal Calprotectin Zn-Acquisition System, TdfH, and the Efficacy of Metal Starvation for Treating Gonococcal Disease.

By Michael T. Kammerman, B.S.

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University

Virginia Commonwealth University, 2020

Major Director: Cynthia Nau Cornelissen, Ph.D.

Professor, Department of Microbiology and Immunology

Neisseria gonorrhoeae, the bacterial agent that is responsible for the human disease gonorrhea, has had a steady increase in the number of infections per year. In 2018 the WHO estimated over 87 million infections occurred world-wide, and the CDC …


Effects Of (R,S)-Ketamine And (2r,6r)-Hydroxynorketamine: A Preclinical Study, Remington Rice Jan 2020

Effects Of (R,S)-Ketamine And (2r,6r)-Hydroxynorketamine: A Preclinical Study, Remington Rice

Theses and Dissertations

In 2017, 7.1% of US adults were diagnosed with depression, and 50% of patients received medication to treat their depression. Depression can cause severe interruptions in an individual's cognitive functioning and behaviors like sleeping, eating, working, and socializing. Unfortunately, approximately 40% of patients do not respond to treatment with monoaminergic medications (e.g. Prozac) and therapeutic effects may be delayed 2-8 weeks. Due to these therapeutic shortcomings, faster acting and more efficacious treatments are needed. Recent preclinical findings indicate potential for glutamatergic drugs like (R,S)-ketamine and (2R,6R) hydroxynorketamine to produce more rapid and longer-acting therapeutic effects. The antidepressant effectiveness of (R,S)-ketamine …


Prediction Of The Vaginal Microbiome Using Urine Samples, Christopher R. Diachok Jan 2020

Prediction Of The Vaginal Microbiome Using Urine Samples, Christopher R. Diachok

Theses and Dissertations

The vaginal microbiome is associated with women’s health, including but not limited to the pathogenesis of bacterial vaginosis, adverse pregnancy outcomes including preterm birth and sexually transmitted infections. However, there has been very limited research on the urinary microbiome and its relationship to the vaginal microbiome. We sought to predict the vaginal microbiome profile using clean catch urine samples from the same person. Here, paired vaginal and urine samples were collected and sequenced by 16S ribosomal RNA sequencing. Alpha and beta diversity analysis showed that there was no significant difference between the paired vaginal and urine microbiomes. In fact, a …


The Role Of Manganese In Streptococcus Sanguinis, Tanya M. Puccio Jan 2020

The Role Of Manganese In Streptococcus Sanguinis, Tanya M. Puccio

Theses and Dissertations

Streptococcus sanguinis is primarily associated with oral health as a commensal bacterium. As an opportunistic pathogen, S. sanguinis is capable of colonizing heart valve vegetations, leading to the disease infective endocarditis. Previous studies from our lab have identified the high-affinity manganese transporter SsaACB as important for endocarditis virulence. The impact that manganese depletion has on S. sanguinis had never been evaluated and a secondary manganese transporter has not been identified. Thus, we employed the use of a fermentor to control large-scale growth over time and depleted manganese in an ΔssaACB mutant using a metal chelator, EDTA. The changes in …


Illumination Of The Golgi Apparatus Of Pathogenic And Nonpathogenic Naegleria Species, Tyler M. Poe Jan 2019

Illumination Of The Golgi Apparatus Of Pathogenic And Nonpathogenic Naegleria Species, Tyler M. Poe

Theses and Dissertations

In this study, Naegleria fowleri, a pathogenic amoeba and the causative agent of Primary Amebic Meningoencephalitis (PAM), was utilized to determine the presence or absence of classically conserved Golgi molecules featured in the expression of a Golgi apparatus. Previous studies concluded no Golgi expression via light microscopy and transmission electron microscopy, but a recent report on Naegleria gruberi indicated the presence of dispersed Golgi tubules. Non-pathogenic species of the Naegleria genus such as Naegleria gruberi 30540 and Naegleria lovaniensis 30569 were utilized in Western immunoblot analysis compared to reduced whole-cell lysate proteins of two strains of N. fowleri and …


Usefulness Of The Captia Syphilis Igg Eia Test Method And Reverse Algorithm For Detection Of Syphilis Infection In A Public Health Setting, Patricia Armour Jan 2018

Usefulness Of The Captia Syphilis Igg Eia Test Method And Reverse Algorithm For Detection Of Syphilis Infection In A Public Health Setting, Patricia Armour

Theses and Dissertations

Syphilis, a systemic sexually transmitted disease, is on the rise in the US, with infection rates the highest recorded since 1994 according to the CDC. Useful laboratory testing is an important diagnostic tool for determining individual syphilis infection and preventing community-wide disease spread.

The purpose of this study was to determine the usefulness of a specific automated treponemal test method, the CaptiaTM Syphilis IgG EIA, and the syphilis reverse algorithm interpretation for detecting syphilis infection among patients seeking care in a public health clinic. The study employed a retrospective, nonexperimental descriptive correlational design with data collected between 2012-2013 from …


A Systems Biology Approach For Predicting Essential Genes And Deciphering Their Dynamics Under Stress In Streptococcus Sanguinis, Fadi El-Rami Jan 2017

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 …


Characterization Of A Novel Protease In Staphylococcus Aureus, Adam L. Johnson Jan 2015

Characterization Of A Novel Protease In Staphylococcus Aureus, Adam L. Johnson

Theses and Dissertations

A newly discovered cysteine protease, Prp, has been shown to perform an essential, site-specific cleavage of ribosomal protein L27 in Staphylococcus aureus. In Firmicutes and related bacteria, ribosomal protein L27 is encoded with a conserved N-terminal extension that must be removed to expose residues critical for ribosome function. Uncleavable and pre-cleaved variants were unable to complement an L27 deletion in S. aureus, indicating that this N-terminal processing event is essential and likely plays an important regulatory role. The gene encoding the responsible protease (prp) has been shown to be essential, and is found in all organisms …


Proof-Of-Concept Of Environmental Dna Tools For Atlantic Sturgeon Management, Jameson Hinkle Jan 2015

Proof-Of-Concept Of Environmental Dna Tools For Atlantic Sturgeon Management, Jameson Hinkle

Theses and Dissertations

Abstract

The Atlantic Sturgeon (Acipenser oxyrinchus oxyrinchus, Mitchell) is an anadromous species that spawns in tidal freshwater rivers from Canada to Florida. Overfishing, river sedimentation and alteration of the river bottom have decreased Atlantic Sturgeon populations, and NOAA lists the species as endangered. Ecologists sometimes find it difficult to locate individuals of a species that is rare, endangered or invasive. The need for methods less invasive that can create more resolution of cryptic species presence is necessary. Environmental DNA (eDNA) is a non-invasive means of detecting rare, endangered, or invasive species by isolating nuclear or mitochondrial DNA (mtDNA) from the …


Modeling Thermal Inactivation Of Bacillus Spores, Emily A. Knight Mar 2009

Modeling Thermal Inactivation Of Bacillus Spores, Emily A. Knight

Theses and Dissertations

This research models and analyzes methods to damage Bacillus anthracis spores through heat treatment. AFIT researchers have developed methods to characterize the effects of heating spores to high temperatures and for short durations similar to the thermal pulse of conventional weapon detonation. This research models the current experiment and evaluates the rate of thermal diffusion throughout the spores. A micro-model of the effects of dry and wet heating on a spore is presented. Heating a spore energizes adsorbed, absorbed, and chemically bound water molecules. These energized molecules have greater mobility within the spore, as well as between the spore and …


Micro-Etched Platforms For Thermal Inactivation Of Bacillus Anthracis And Bacillus Thuringiensis Spores, Leslie S. Hawkins Mar 2008

Micro-Etched Platforms For Thermal Inactivation Of Bacillus Anthracis And Bacillus Thuringiensis Spores, Leslie S. Hawkins

Theses and Dissertations

This research developed and applied microlithography techniques to etch microscope slide platforms in order to measure thermal inactivation of Bacillus thuringiensis and Bacillus anthracis spores, two closely related Bacillus species. B.t. is widely used as a surrogate for B.a. in response studies and in some field studies. This work addressed the previously identified problem of measuring both spore growth and spore thermal kill threshold using the traditional method of spreading a diluted spore solution on a plate. The micro-etched platforms forced spore separation thereby preventing neighbor growth from obscuring germination and initial vegetative growth measurements using a microscope. The technique …