Bacterial Infections and Mycoses Commons^™

Development Of A Proposed Selective Medium For The Isolation And Differentiation Of P. Sordellii, Dimyana Bottros

Honors Undergraduate Theses

Clostridium, a genus of anaerobic, spore-forming bacteria, includes clinically and ecologically significant species like Clostridium difficile and Paeniclostridium sordellii. C. difficile causes antibiotic-associated colitis, while P. sordellii is linked to fatal infections and spontaneous abortions. Recent studies found both species in marine sediments, suggesting their role in environmental and wildlife health disturbances, including the 2013 mass mortality of over 300 manatees in the Indian River Lagoon. However, isolating and differentiating P. sordellii is challenging due to the lack of selective media optimized for its growth. This thesis proposes a novel selective medium tailored to P. sordellii’s physiological …

Epitope Mapping Novel Monoclonal Antibodies Against Borrelia Burgdorferi Surface Proteins Ospc And Bmpa, Eliza M. Doyle

Honors Undergraduate Theses

In response to the progressive nature of Lyme disease, direct diagnostic testing of Borrelia burgdorferi surface proteins was proposed as a quicker and more sensitive alternative to the current indirect detection methods. To determine the ability of novel monoclonal antibodies to detect the surface lipoproteins BmpA and OspC, recombinant fragments of these proteins were created. These fragments were tested against the putative diagnostic antibodies via western blotting as a means to map the epitope of each of the proteins that the respective antibodies recognize. All BmpA fragments with deletions on the N-terminal end exhibited reactivity, indicating that the epitope is …

Effectiveness Of Doxycycline As Post-Exposure Prophylaxis (Doxy-Pep) For Bacterial Sexually Transmitted Infections (Stis) Among Men Who Have Sex With Men (Msm) In Central Florida, Micah P. Greer

Honors Undergraduate Theses

Bacterial sexually transmitted infections (STIs), notably syphilis, gonorrhea, and chlamydia, have been increasing among men who have sex with men (MSM) in the United States. The rise has been attributed to various factors, including increased condomless sexual acts due to the high uptake of pre-exposure prophylaxis (PrEP) for HIV prevention. To address this concerning trend, post-exposure prophylaxis with doxycycline (Doxy-PEP) has emerged as a potential biomedical intervention. This study aimed to assess the effectiveness of Doxy-PEP in preventing bacterial STIs among MSM in Central Florida, a region with rising STI rates. A de-identified dataset from Pineapple Health Clinic in Orlando, …

Clostridioides Difficile: Identification Of Rival Organisms & Evaluation Of Non-Antibiotic Treatment Implementation, Justin Davis

Honors Undergraduate Theses

Clostrioides difficile is a common cause of nosocomial (hospital-acquired) infections. Patients receiving antibiotic treatment experience dysbiosis of gut microbiota, and C. difficile, normally held in check by the various other organisms, takes this opportunity to propagate. Symptoms of infection generally include diarrhea, colitis, dehydration, and fever. Understanding that C. difficile generally only causes illness when it is the dominant bacterium (i.e. when growth is relatively unchecked by other microbes), it is appropriate to investigate potential competitive organisms that may be introduced after antibiotic courses or during active C. difficile infection to effectively displace it. Fecal samples from the University …

Trends In Antibiotic Susceptibility Of Staphylococcus Aureus Isolates In A Pediatric Hospital: An Analysis Of The Impact Of The Sars-Cov-2 Pandemic, Juan Miguel S. Gonzalez Rivero

Honors Undergraduate Theses

Infections caused by the organism Staphylococcus aureus are one of the most common causes for community-associated and healthcare-acquired infections (HAI). Isolates of this bacterium found within the healthcare setting often demonstrate a higher prevalence of antibiotic resistance making these infections difficult to treat. Historically, considerable focus has been placed on methicillin-resistant S. aureus (MRSA), which are strains resistant to β-lactam antibiotics like penicillin, oxacillin and cephalosporins; however, methicillin-sensitive (MSSA) strains may also possess resistance to several first-line antibiotics. Resistance to antibiotics can be acquired through horizontal gene transfer (HGT) by means of mobile genetic elements or by random DNA mutations …

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 …

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 …

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 …