Bacterial Infections and Mycoses Commons^™

Reexamining Cytolethal Distending Toxin's Host Cell Entry And Trafficking: The First Steps Down A Long Road, George Huhn

Electronic Theses and Dissertations, 2020-

Cytolethal distending toxin (CDT) is a virulence factor produced by many Gram-negative bacteria, including Haemophilus ducreyi, the causative agent of genital chancroid. CDT is a heterotrimeric toxin consisting of a cell-binding domain (CdtA + CdtC) and a catalytic domain (CdtB) that has DNase activity. After binding to the host plasma membrane, CDT undergoes endocytosis and travels through the endosomes en route to the endoplasmic reticulum (ER). Only CdtB and CdtC arrive in the Golgi before moving to the ER. Only then does CdtB move into the nucleus, causing DNA damage that induces cell-cycle arrest and apoptosis. The previous CDT trafficking …

Cholera Transmission Dynamic Model With Environmental Impacts Of Plankton Reservoirs, Sweety Sarker

Electronic Theses and Dissertations, 2020-

Cholera is an acute disease that is a global threat to the world and can kill people within a few hours if left untreated. In the last 200 years, seven pandemics occurred, and, in some countries, it remains endemic. The World Health Organization (WHO) declared a global initiative to prevent cholera by 2030. Cholera dynamics are contributed by several environmental factors such as salinity level of water, water temperature, presence of plankton especially zooplankton such as cladocerans, rotifers, copepods, etc. Vibrio cholerae (V. cholerae) bacterium is the main reason behind the cholera disease and the growth of V. cholerae depends …

Chitosan-Gallium Nanocomposite: Synthesis, Characterization And Antibacterial Activity, Samjhana Bhandari

Electronic Theses and Dissertations, 2020-

The emergence of multidrug-resistant (MDR) strains of bacteria and the lack of a novel class of antibiotics has become a global health concern. Pseudomonas aeruginosa is one common MDR bacteria responsible for nosocomial infections and related mortality worldwide. It has developed resistance against commonly available antibiotics and is in the WHO's priority list of bacteria for which new antibiotics are desperately needed. Currently there is a growing interest in developing metal and non-metal-based nanoparticles to target multidrug-resistant bacteria. The objective of this study is to evaluate the efficacy of a novel nanocomposite of two non-traditional antimicrobials: a metal (Ga-III) and …

Role Of Rela In Dormancy And Toxr Proteolysis In Vibrio Cholerae, Zachary J. Malaussena

Honors Undergraduate Theses

Vibrio cholerae, the etiological agent of the severe diarrheal disease cholera, is an enteric pathogen that can be found in aquatic ecosystems when not colonizing the human gastrointestinal tract. Under adverse environmental conditions, V. cholerae is capable of entering dormant states that increase its survival during these ecological fluctuations. In these states, V. cholerae slows its metabolic activity and exhibits drastically altered gene expression and morphology. Stressors that lead to entry into these states vary from nutrient limitation, suboptimal pH, or antimicrobials. Cells in these dormant states are highly resistant to antimicrobials and cannot be detected using standard microbiological techniques …

Cerium Oxide Nanoparticles And Beneficial Bacteria: Two Novel Treatments For Eradicating Bacteria Associated With Prosthetic Infection?, Etta Conteh

Honors Undergraduate Theses

The purpose of this thesis was to investigate new possible compounds that can be used to treat orthopedic implant infections caused by bacterial pathogens. Current treatment includes the use of antibiotics and the DAIR procedure, which stands for debridement, antibiotic therapy, irrigation, and retention. However, antibiotics are becoming less effective as a treatment due to bacteria gaining antibiotic resistance. Two bacterial species involved in orthopedic implant infections are P. aeruginosa and S. aureus. This thesis investigated cerium oxide nanoparticles and L. fermentum, a beneficial bacterium, as possible treatments to stop bacterial growth and the formation of biofilm. This …

Detection Of Point Mutations Conferring Gentamicin Resistance In Escherichia Coli Using A Split-G4 Probe, Michael J. Greenberg

Honors Undergraduate Theses

The objective of this project was to develop a DNA hybridization sensor that can detect the presence of E. coli and reveal its resistance to the drug gentamicin. This probe will enable rapid and user-friendly diagnostics of E. coli infections and analysis of bacterial gentamicin-susceptibility profile by interrogation of a fragment of E. coli 16S rRNA bearing a substitution in the gentamicin-resistant cells. The sensor is promising for the point-of-care use to provide a timely UTI diagnostic solution. A quick diagnosis of E. coli infection and antibiotic resistance is crucial for treatment. To design a hybridization probe, we proposed a …

Modeling Disease Impact Of Vibrio-Phage Interactions, Christopher Botelho

Electronic Theses and Dissertations

Since the work of John Snow, scientists and medical professionals have understood that individuals develop cholera by means of consuming contaminated water. Despite the knowledge of cholera's route of infection, many countries have experienced and still experience endemic cholera. Cholera is caused by the Vibrio cholerae (V. cholerae) bacterium and presents with acute diarrhea and vomiting. If untreated, infected individuals may die due to dehydration. Cholera is a disease that most commonly affects countries with poor infrastructure and water sanitation. Despite efforts to control cholera in such countries, the disease persists. One such example is Haiti which has been experiencing …

The Envelope Stress Response In Sedimentation-Resistant Escherichia Coli, Neel K. Shah

Honors Undergraduate Theses

Previous research discovered the existence of sedimentation-resistant mutants of E. coli. Genomic studies revealed that these mutants resisted sedimentation due to independent modifications to genes that influenced the Rcs signal transduction pathway, causing increased secretion of an exopolysaccharide capsule comprised primarily of colanic acid. The Rcs system is responsible for detecting envelope stressors; consequently, ampicillin and osmotic stress were used to perturb the cellular envelope and study the response of the mutants compared to wild-type cells. It was found that the overproduction of colanic acid in the mutants confers some resistance to envelope stress; however, the mutants still behaved …

Etiology Of Community Acquired Clostridium Difficile-Associated Disease, Shannan Sherman, Dr. Pamela Ark

The Pegasus Review: UCF Undergraduate Research Journal

A review of literature related to community acquired Clostridium difficile -associated disease (CA-CDAD) was conducted. Nine relevant studies were identified using the Cumulative Index to Nursing and Allied Health (CINAHL) and MEDLINE-EBSCOhost databases. Clinical practice recommendations were obtained from the Centers for Disease Control and Prevention. The studies provided information about epidemiology of infection due to C. difficile in the community and interventions to reduce transmission. Multiple studies found underlying gastrointestinal disorders and use of cephalosporin antibiotics to be a risk factor. Another risk factor was administration of gastric acid suppressive drugs. No particular C. difficile strain was more likely …

Aeromonas Hydrophila In Amphibians: Harmless Bystander Or Opportunistic Pathogen, Zachary P. Rivas

Honors Undergraduate Theses

For several decades amphibian populations have been declining. Historically, the bacterium A. hydrophila (Ah) was hypothesized to be the causal factor in amphibian disease and population declines. However, with the discovery of a chytrid fungus, Batrachochytrium dendrobatidis (Bd) in 1998, which was identified on the skin of amphibians during documented mortality events, Ah research became of minor interest as focus shifted to Bd. Recent studies into the immunocompromising abilities of Bd, however, have opened new questions about its relationship with Ah and their combined effects on a host.

In this study, I explore the …

Evaluation Of Immunogenicity Of Transgenic Chloroplast Derived Protect, Vijay Koya

Electronic Theses and Dissertations

Anthrax, a fatal bacterial infection is caused by Bacillus anthracis, a gram-positive, spore forming, capsulated, rod shaped organism. Centers for Disease Control (CDC) lists anthrax as Category A biological agent due to its severity of impact on human health, high mortality rate, acuteness of the disease and potential for delivery as a biological weapon. The currently available human vaccine in the United States (AVA anthrax vaccine adsorbed) is prepared from Alum adsorbed formalin treated supernatant culture of toxigenic, non-encapsulated strain of Bacillus anthracis with the principle component being protective antigen (PA83). Evaluation of anthrax vaccine given to nearly 400,000 US …