Bacterial Infections and Mycoses Commons^™

The Impact Of Candida Albicans Glycogen On Fitness, Virulence And Host Response, Jian Miao

Theses and Dissertations (ETD)

Candida albicans is an opportunistic human fungal pathogen that presents in healthy persons colonizing the oropharyngeal, esophageal, and gastrointestinal mucosa. This polymorphic fungal pathogen remains a leading cause of both invasive and superficial mycoses. C. albicans can cause oropharyngeal candidiasis (OPC) and disseminated candidiasis when normal host immunity is disturbed, while also causing vulvovaginal candidiasis (VVC) in healthy women. Adaptation to different host niches requires rapid and coordinated changes in Candida metabolism and physiology to cope with host immune surveillance and to counteract host-imposed constraints such as glucose limitation. Although largely unexplored in C. albicans, the glycogen metabolism pathway is …

Ftsk Regulates The Assembly Of The Division Machinery In The Ftsz-Less Chlamydia Trachomatis, Mckenna Katherine Harpring

Theses and Dissertations (ETD)

In evolving to obligate intracellular dependence, Chlamydia trachomatis serovar L2 (Ct), has eliminated several gene products essential for cell division in most other bacteria, including FtsZ, the central coordinator of divisome assembly. In the absence of FtsZ, we show that divisome assembly in Ct is initiated by FtsK, a chromosomal translocase. Chlamydial FtsK forms discrete foci at the septum and at the base of the progenitor mother cell, and our data indicate that FtsK foci at the base of the mother cell mark the location of nascent divisome complexes that form at the site where a daughter cell will emerge …

Promising Changes In Antibiotic Utilization Associated With Implementation Of Rapid Multiplex Polymerase Chain Reaction Testing For Bloodstream Infection, Tat Yau, Michelle Blyth, Julio E. Figueroa Ii

School of Medicine Faculty Publications

Infectious Diseases Week, IDWeek 2023, October 11-15, 2023, Boston, MA

One Vs Three Weekly Doses Of Benzathine Penicillin G For Treatment Of Early Syphilis In Persons With And Without Hiv: A Multicenter Randomized Controlled Trial (Rct), Edward W. Hook, Kimberly Workowski, Jodie A. Dionne, Candice J. Mcneil, Stephanie N. Taylor, Batteiger Teresa, Julia C. Dombrowski, Kenneth H. Mayer, Arlene C. Seña, Harold C. Wiesenfeld, Charlotte Perlowski, Lori Newman, Chunming Zhu, Jorge E. Mejia-Galvis

School of Medicine Faculty Publications

Infectious Diseases Week, IDWeek 2023, October 11-15, 2023, Boston, MA

The Implications Of Ferroptosis In Antibiotic Resistance, Marysol Hohl

Senior Honors Theses

Bacterial infections in the United States are becoming increasingly resistant to existing antibiotic treatments. Due to projected increases in resistance and the recent decrease in novel antibacterials, experts have determined that the United States is in the “post-antibiotic era.” The scientific community has failed to resolve resistance despite the continual discovery of new antibiotic compounds. In the past decade, a novel form of cell death called ferroptosis has been implicated in antibiotic treatment by employing the use of nanotechnology. This literature review will describe the problem of bacterial resistance and demonstrate how current research is pioneering a new age of …

Rare Case Of Prosthetic Joint Infection Caused By Salmonella Enterica - A Case Report, Carlos Ramos, Shyama Appareddy, Peter J. Gonzalez

Research Colloquium

Introduction: Collectively, over 1 million total knee arthroplasties (TKA) and total hip arthroplasties (THA) are performed in the United States each year. In 2010 it was estimated that 1.58% of the United States general population has received a TKA. Prosthetic joint infections (PJI) are the most common indication for a TKA revision1 . In total, S. aureus is responsible for about 50% of all prosthetic joint infections, and about 15% are caused by gram negative pathogens2 .

Objective: This is a case report which describes the presentation and clinical course of a 59-yearold female with Salmonella enterica septic arthritis of …

Catheter-Associated Urinary Tract Infections: Patient Characteristics, Treatment, And Clinical Outcomes In One South Texas Acute Care Hospital, Kimberly A. Ambrosini, Jose Campo Maldonado

Research Colloquium

Background: Catheter-associated urinary tract infections (CA-UTIs) account for 40 percent of nosocomial infections worldwide. Their elimination is at the forefront of quality improvement in one South Texas acute care hospital.

Methods: Over a period of 6 months, five CA-UTIs occurred in one South Texas acute care hospital. These cases were identified via regular surveillance by Infection Prevention staff and the Laboratory Department of the hospital. This research reviews patient age, sex, length of stay, bacteria contracted, appropriate antibiotic use, patient characteristics, and overall outcomes.

Results: Between the months of July and December 2021, 5 CAUTIs were contracted. Patients ranged in …

Human Alcohol-Microbiota Mice Have Increased Susceptibility To Bacterial Pneumonia, Kelly C. Cunningham, Deandra R. Smith, Daniel N. Villageliú, Christi M. Ellis, Amanda E. Ramer-Tait, Jeffrey D. Price, Todd A. Wyatt, Daren L. Knoell, Mystera M. Samuelson, Patricia E. Molina, David A. Welsh, Derrick R. Samuelson

School of Medicine Faculty Publications

Preclinical studies have shown that chronic alcohol abuse leads to alterations in the gastrointestinal microbiota that are associated with behavior changes, physiological alterations, and immunological effects. However, such studies have been limited in their ability to evaluate the direct effects of alcohol-associated dysbiosis. To address this, we developed a humanized alcohol-microbiota mouse model to systematically evaluate the immunological effects of chronic alcohol abuse mediated by intestinal dysbiosis. Germ-free mice were colonized with human fecal microbiota from individuals with high and low Alcohol Use Disorders Identification Test (AUDIT) scores and bred to produce human alcohol-associated microbiota or human control-microbiota F1 progenies. …

Is Β-Lactamase Testing Acceptably Accurate For Predicting Haemophilus Influenzae Susceptibility To Β-Lactams? Epidemiological Data From Philadelphia, Usa, 2017–2023, Arianna B. Morton, Chairut Vareechon, Matthew A. Pettengill

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

No abstract provided.

Analyzing Pseudomonas Aeruginosa With Bacteriophage Tags Using Photoacoustic Flow Cytometry, Jennifer C. Schinke

Electronic Theses and Dissertations

The number of daily bacterial infections is climbing and the CDC explains that this is due to the antibiotic-resistant threat in the United States. Finding a faster way of bacterial identification is necessary as it currently takes 1-4 days for a medical lab to culture and identify bacteria. Photoacoustic flow cytometry (PAFC) can be used as an alternative method resulting in swift identification within an hour (Edgar, 2019). Pseudomonas aeruginosa, cell line PA01, will be coated in up to a few hundred red dyed phages making it detectible by the photoacoustic flow cytometry system. Bacteriophages (phages) are viruses that …

A Qualitative Analysis Of Candida Auris Laboratory Surveillance In Nebraska, Lissa M. Young

Capstone Experience: Master of Public Health

Objectives: Candida auris is an emerging pathogenic yeast that was first identified in Japan in 2009 and detected in the United States in 2015. As of 2020, C. auris has been reported in cases throughout 41 countries, including the United States. The ability of this species of yeast to spread rapidly and survive for long periods of time on surfaces, the high mortality rate of those infected, and its multidrug resistant phenotype, have rendered it a urgent public health threat (the highest threat level) by the United States Centers for Disease Control and Prevention beginning in 2019 (CDC, 2019). Since …

A Novel Gardnerella, Prevotella, And Lactobacillus Standard That Improves Accuracy In Quantifying Bacterial Burden In Vaginal Microbial Communities, Jacob H. Elnaggar, Caleb M. Ardizzone, Nuno Cerca, Evelyn Toh, Paweł Łaniewski, Rebecca A. Lillis, Melissa M. Herbst-Kralovetz, Alison J. Quayle, Christina A. Muzny, Christopher M. Taylor

School of Graduate Studies Faculty Publications

Bacterial vaginosis (BV) is the most common vaginal dysbiosis. In this condition, a polymicrobial biofilm develops on vaginal epithelial cells. Accurately quantifying the bacterial burden of the BV biofilm is necessary to further our understanding of BV pathogenesis. Historically, the standard for calculating total bacterial burden of the BV biofilm has been based on quantifying Escherichia coli 16S rRNA gene copy number. However, E. coli is improper for measuring the bacterial burden of this unique micro-environment. Here, we propose a novel qPCR standard to quantify bacterial burden in vaginal microbial communities, from an optimal state to a mature BV biofilm. …

Stewardship Opportunities For Cervical Lymphadenitis And Deep Neck Space Abscesses, Aaron Shaw, Brian R. Lee, Lauren Kazmaier, Emily Baker, Tina Dao, Sandra Arnold, Angela Myers

Research Days

Background: Cervical lymphadenitis (LAD) and deep neck space abscesses (DNSA) are common pediatric infections caused by similar bacteria. We sought to determine differences in presentation, diagnosis, and treatment between LAD and DNSA to identify antimicrobial and diagnostic stewardship opportunities.

Methods: Charts were obtained using ICD9/10 codes for retropharyngeal and parapharyngeal abscessed (DNSA), and LAD between 1/1/10-12/31/20 from two pediatric centers. 1981 charts were identified. Charts were excluded if the diagnosis was not a bacterial infection (e.g. Kawasaki disease), if the LAD was not in the neck, or if caused by less common bacteria (e.g. tuberculosis). Data on presenting signs, symptoms, …

Elucidating The Impact Of Sos-Response Timing In On Escherichia Coli Survival Following Treatment With Fluoroquinolone Topoisomerase Inhibitors, Stephanie Schofield

Honors Scholar Theses

Antibiotic treatment failure is a public health crisis, with a 2019 report stating that roughly 35,000 deaths occur in the United States yearly due to bacterial infections that are unresponsive to antibiotics (1). One complication in the treatment of bacterial infection is antibiotic persistence which further compromises our battle to effectively treat infection. Bacterial persisters can exist in clonal bacterial cultures and can tolerate antibiotic treatment by undergoing reversible phenotypic changes. They can survive drug concentrations that their genetically identical kin cannot. Some persisters remain in a slow growing state and are difficult to target with current antibiotics. A specific …

Effect Of Temperature On The Microbiome Of A Laboratory Reared Colony Of Haemaphysalis Longicornis Ticks, Brianna Mitchell

Poster Presentations

Honors research poster.

Haemaphysalis longicornis is a species of tick native to eastern Asia, including eastern China, Japan, eastern Russia, and Korea. To date, it has invaded and has now established its existence in Australia, New Zealand, and several of the Pacific Islands. This species of tick has recently been introduced to the United States, having a confirmed sighting in November 2017 on a sheep farm in New Jersey and since establishing populations in 18 states along the east coast and Appalachia. Based on the existing locations of H. longicornis in its native regions, as well as in the United …

Immunomodulatory Effects Of Resolvin D2 In A Model Of Infection, Prem Yugandhar Kadiyam Sundarasivarao

Graduate School of Biomedical Sciences Theses and Dissertations

Dysregulated hyperinflammatory host immune response to underlying bacterial infections is a characteristic of sepsis. In sepsis, bacteria often trigger abnormal hyperinflammatory responses which can cause multiple organ failure and if sustained can lead to an immunosuppressive phase where the host is susceptible to secondary infections caused by opportunistic bacteria like Pseudomonas aeruginosa (P. aeruginosa). In our studies, we used a 2-hit model of cecal ligation and puncture (CLP) followed by P. aeruginosa secondary lung infection to investigate cellular and molecular mechanisms in the beneficial action of resolvin D2 (RvD2). Resolvins of the D-series are a group of fatty acids known …

Role Of Pseudomonas Aeruginosa Exoenzymes S, T, And Y In The Modulation Of Intrinsic Apoptosis In Pulmonary Microvascular Endothelial Cells, Andrea M. Vavrinek

Honors Theses

P. aeruginosa is the most common cause of ventilator-associated pneumonia in ICU patients. P. aeruginosa uses a type III secretion system to inject exoenzymes S, T, U, and Y into host cells, exhibiting unique effects. Pulmonary microvascular endothelial cells (PMVECs) are used to evaluate cellular changes caused by exoenzymes. ExoY infection of PMVECs leads to cell rounding but does not lead to cell death, unlike ExoS/T. The current study evaluated the exoenzyme-induced modulation of intrinsic apoptosis in endothelial cells. Strain PAK, producing ExoS, T, and Y, was compared to isogenic strains expressing either S, SY, T, TY, Y, or none …

A Review Of Staphylococcus Aureus Pathogenesis, Global Impact, And The Rise Of Antibiotic-Resistant Clones, Anders Kleinbeck

Honors Scholar Theses

Staphylococcus aureus is a pathogen of grave concern to global public health. The pathogen has shown an unrivaled propensity to obtain resistance to nearly every antibiotic drug approved and prescribed for its treatment. This review will provide an overview of the history and evolution of S. aureus, including an analysis of its transition from the nosocomial setting to the community and the factors contributing to the species’ innate pathogenicity. This paper will also discuss the molecular mechanisms by which resistance to a wide range of popular antibiotic substances was obtained and will provide insight into the evolutionary patterns exhibited by …

Diagnosis Of Urinary Tract Infections And Rapid Molecular Characterization Of Antibiotic Resistance, Mohammed Harris

All Dissertations

Urinary tract infections (UTIs) are one of the most common infectious clinical entities in both community and hospital settings. They have a broad range of clinical severity yet inflict large epidemiological burden of morbidity and mortality on patients and the healthcare system with billions of dollars in cost of treatment. Understanding what methods are optimal for diagnosing UTIs are critical to mitigate the marked impact and cost of these infections.

Chapter 1 and 2 in this work surveys the broad array of diagnostic modalities for UTIs and highlights their advantages and limitations in the context of the current standard of …

The Effects Of Specialized Pro-Resolving Mediator Lipoxin A4 On Pseudomonas Aeruginosa Biofilms And Interactions With Monocytes, Julianne M. Thornton

Graduate School of Biomedical Sciences Theses and Dissertations

Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogen known as a major cause of hospital-acquired secondary infections, commonly causing chronic respiratory infections in immunocompromised individuals, especially those with cystic fibrosis, and often found in wound infections. P. aeruginosa uses the quorum sensing pathway to readily form protective biofilms, which reduce the efficacy of antibiotics and access by host immune cells to eradicate the pathogen. Specialized pro-resolving mediators (SPMs) are lipids endogenously produced by the host immune response to infection to aid in infection resolution. One SPM, Lipoxin A4 (LxA4), has been shown to be a robust quorum sensing inhibitor.

The …

Accuracy Of Therapeutic Drug Monitoring In Vancomycin And The Pharmacist Role: A Retrospective Case-Series, Kateryna Parkhomenko

Senior Theses

Vancomycin is a mainstay of therapy for treating virulent and resistant infections, especially methicillin-resistant Staphylococcus aureus (MRSA). However, vancomycin requires therapeutic drug monitoring (TDM) for optimal dosing and treatment. This requires pharmacists to calculate a dosing regimen that correlates to appropriate goal vancomycin concentrations in the blood. Dosing vancomycin can be difficult, as it varies on a patient’s weight, renal function, age, etc. Doses may have to be adjusted in response to out-of-range concentrations, which requires further pharmacy calculations. Inaccurate dosing poses a risk to patient safety and places a resource and time burden on pharmacists. If vancomycin dosing methods …

Investigation Of Clinically Relevant Fluconazole Resistance Mechanisms In The Fungal Pathogen Candida Parapsilosis, Laura Anne Doorley

Theses and Dissertations (ETD)

Invasive candidiasis is a severe fungal infection associated with significant morbidity and mortality, particularly among the critically ill and immunocompromised. Candida parapsilosis is the most common non-albicans species causing invasive Candida infections in pediatric and neonatal populations worldwide and is particularly common in the countries of South America, Western Asia, Mediterranean Europe, and Southern Africa. For many of these countries, fluconazole and other triazoles are the first line antifungal agents used for effective treatment of invasive Candida infection. Until recently, rates of fluconazole resistance among C. parapsilosis isolates were relatively low, therefore the determination of clinically relevant resistance mechanisms in …

Topical Anesthetic Gel Interferes With Antibacterial Efficacy Of Povidone-Iodine Both In Vitro And In Vivo, Cecilly Kelleher Bs, Jacob Im Md, Linda Kang Bs, Aleksey Mishulin Md, Sukhvinder Singh Phd, Ashok Kumar Phd

Medical Student Research Symposium

Purpose: To evaluate the effects of viscous lidocaine gel on the antimicrobial efficacy of povidone-iodine (PI) and their order of application in both in vitro and in vivo models.

Methods: In vitro antibacterial effects were tested against Staphylococcus aureus (S. aureus) with disc diffusion methods for application of lidocaine alone, PI alone, PI before lidocaine, and lidocaine before PI. Zones of inhibition were measured after incubation at 37°C overnight. Mouse eyes were colonized with S. aureus for in vivo study to which PI and/or lidocaine were applied in various combinations. Eyes were then rinsed with saline, and …

From Tuberculosis Bedside To Bench: Ube2b Splicing As A Potential Biomarker And Its Regulatory Mechanism, Mengyuan Lyu, Jian Zhou, Yanbing Zhou, Weelic Chong, Wei Xu, Hongli Lai, Lu Niu, Yang Hai, Xiaojun Yao, Sheng Gong, Qinglan Wang, Yi Chen, Yili Wang, Liyu Chen, Ganzi People's Hospital, Jiongjiong Zeng, Chengdi Wang, Binwu Ying

Student Papers, Posters & Projects

Alternative splicing (AS) is an important approach for pathogens and hosts to remodel transcriptome. However, tuberculosis (TB)-related AS has not been sufficiently explored. Here we presented the first landscape of TB-related AS by long-read sequencing, and screened four AS events (S100A8-intron1-retention intron, RPS20-exon1-alternaitve promoter, KIF13B-exon4-skipping exon (SE) and UBE2B-exon7-SE) as potential biomarkers in an in-house cohort-1. The validations in an in-house cohort-2 (2274 samples) and public datasets (1557 samples) indicated that the latter three AS events are potential promising biomarkers for TB diagnosis, but not for TB progression and prognosis. The excellent performance of classifiers further underscored the diagnostic value …

Sulopenem For The Treatment Of Complicated And Uncomplicated Bacterial Urinary Tract Infection (Uti), Aiyi Chen, Thanh-Liem Vu, Daniel J. Yang, Landon Olsen

Annual Research Symposium

No abstract provided.

Evaluation Of Antifungal Efficacy In The Treatment Of Candida Auris Bloodstream Infections, Monique Busacay, Kaylee Putney, Rebecca Jayakumar

Annual Research Symposium

No abstract provided.

Chlamydia Trachomatis Subverts Alpha-Actinins To Stabilize Its Inclusion, A. Haines, J. Wesolowski, F. Paumet

Department of Microbiology and Immunology Faculty Papers

Chlamydia trachomatis is the leading cause of sexually transmitted bacterial disease and a global health burden. As an obligate intracellular pathogen, Chlamydia has evolved many strategies to manipulate its host and establish its intracellular niche called the inclusion. C. trachomatis reorganizes the host actin cytoskeleton to form scaffolds around the inclusion and reinforce the growing inclusion membrane. To control the kinetics and formation of actin scaffolds, Chlamydia expresses the effector InaC/CT813, which activates the host GTPase RhoA. Here, we have discovered that InaC stabilizes actin scaffolds through the host actin cross-linking proteins α-actinins 1 and 4. We demonstrate that α-actinins …

Combatting Bacterial Infections: The Efficacy Of Poly-Gamma-Glutamic Acid On The Prevention Of Nasopharyngeal Infections Among Individuals With Cleft Lip And Palate, Florence Pun

Scripps Senior Theses

Cleft lip and palate (CLP) is a medical condition where children are born with an unfused lip and palate. While surgery is required to fuse the lip and palate, there are other conditions that children with CLP face after surgeries, such as otitis media (OM), speech impediments, and difficulty breathing. Particularly, OM occurs frequently in individuals with CLP because the tensor veli palatini muscles cannot open the Eustachian tube frequently and ventilate the middle ear properly, even after surgery. This thesis is a research proposal to evaluate whether γ-PGA can be used in nasal washes to safely prevent nasopharyngeal infections …

Physiologically-Based Pharmacokinetic (Pbpk) Modeling For The Preclinical Development Of Spectinamide Antibiotics, Keyur R. Parmar

Theses and Dissertations (ETD)

Despite being an ancient disease caused by Mycobacterium tuberculosis (Mtb) and after decades of research, tuberculosis (TB) still affects millions of people every year worldwide. In 2018, the World Health Organization (WHO) reported that 10 million people developed tuberculosis and 1.5 million died of the disease. With the increase in the multidrug-resistant (MDR) and extensively drug-resistant (XDR) cases, the treatment for TB with the standard first and second-line therapy is becoming increasingly difficult. Therefore, there is an urgent need to find new anti-TB drugs as combination partners of existing and experimental classes of antimicrobial agents to shorten and simplify the …

Clinical Approach To Evaluation Of Underlying Cardiac Device Infection In Patients Hospitalized With Bacteremia, Dierdre B Axell-House, Sarwat Khalil, M Rizwan Sohail

Faculty, Staff and Students Publications

More than 400,000 cardiac implantable electronic devices (CIEDs), including permanent pacemakers, implantable cardioverter-defibrillators, and cardiac resynchronization therapy devices, are implanted every year in the United States (US). Infection is a serious complication of CIED therapy and is associated with high morbidity and mortality. While CIED pocket infection can be diagnosed based on clinical exam findings, positive blood culture may be the only manifestation of CIED lead infection. Thus, management of bacteremia in patients living with CIEDs requires special consideration. This review summarizes contemporary data in the context of the recently updated 2023 Duke-International Society for Cardiovascular Infectious Diseases Criteria for …