Bacterial Infections and Mycoses Commons^™

A Larval Zebrafish (Danio Rerio) Model Of Adherent-Invasive Escherichia Coli Infections, Erika Flores, Erika Flores

Dissertations & Theses (Open Access)

Inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis, is a broad term for chronic intestinal disorders that severely impact patient morbidity and quality of life. The global prevalence of IBD is rising, with over one million patients affected in the US alone. Adherent-invasive E. coli (AIEC) is a pathobiont frequently found in IBD biopsies. AIEC adhere to and invade epithelial cells, and can survive inside macrophages in vitro. However, how AIEC contributes to IBD in vivo remains unclear. Here a larval zebrafish (Danio rerio) model of AIEC was established, which facilitates the study of the …

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 …

Burkholderia Collagen-Like Protein 8, Bucl8, Is An Outer-Membrane Component Of A Novel Efflux Pump And Immunogenic Vaccine Candidate, Megan Elizabeth Grund

Graduate Theses, Dissertations, and Problem Reports

Burkholderia spp. are Gram‐negative intrinsically resistant bacteria that are responsible for environmental and nosocomial infections of clinical and biodefense concern. Our laboratory previously identified in silico Burkholderia collagen-like protein 8 (Bucl8) in the BSL-3 pathogens Burkholderia pseudomallei and Burkholderia mallei (Figure 1). The protein sequence of Bucl8 contains tandem outer-membrane efflux protein domains (OEP) typical of efflux systems and a unique collagen-like domain (CL) consisting of a repeating sequence of Glycine-Alanine-Serine (GAS). Because efflux pumps are often a mechanism of pathogenicity and antibiotic resistance, we investigated Bucl8 further. Here, we determined that the locus of bucl8 contains genes …

Implantable Medical Devices For Local Drug Delivery And Tissue Regeneration To Combat Chronic Bacterial Infection, Caroline J. Billings

Doctoral Dissertations

Local drug delivery has been an area of exceptional interest in the treatment of chronic bacterial infections, particularly in areas where there are medical implants placed. Medical implants are widely utilized and are becoming increasingly popular with time. With the increasing use of medical implants, concomitant bacterial infection is also increasing, and this type of bacterial infection can be exceedingly difficult to clear. The following body of work focuses on implant-associated bacterial infection, with an emphasis on chronic Staphylococcus aureus (S. aureus) infection, particularly osteomyelitis. Specifically, this work is focused within the scope of utilizing locally implantable medical …

“Pandemias Políticas: The Effects Of Political And Social Instability On Infectious Disease Epidemiology In Latin America"”, Sarah H. Noonan

Senior Theses

This paper seeks to analyze the relationship between political and social unrest and conflict and infectious disease epidemiology in Latin America. An analysis of published literature regarding epidemiological, biomedical, political, and historical content was conducted to highlight potential connections between infectious disease epidemics and sociopolitical conflict in the region. Specific analyses of Smallpox, Venezuelan Equine Encephalitis, Chagas disease, Cholera, Dengue, and COVID-19 were conducted, in an effort to uncover potential causations and context of epidemics of these conditions. Results of this analysis depict a necessity for further research into public health and disease control mechanisms during times of conflict and …

Identification Of Effectors Of Synergistic Lethality In Candida Albicans-Staphylococcus Aureus Polymicrobial Intra-Abdominal Infection, Olivia Adele Todd

Theses and Dissertations (ETD)

Candida albicans, an opportunistic fungal pathogen, and Staphylococcus aureus, a ubiquitous pathogenic bacterium, are among the most prevalent causes of nosocomial infections and cause severe morbidity and mortality. Moreover, they are frequently coisolated from central venous catheters and deep-seated infections, including intra-abdominal sepsis. Relatively little is known about the complex interactions and signaling events that occur between microbes and even less so how microbial “cross-talk” shapes human health and disease.

Using a murine model of polymicrobial intra-abdominal infection (IAI), we have previously shown that coinfection with C. albicans and S. aureus leads to synergistic lethality whereas monomicrobial infection is nonlethal. …

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 …

Examination Of Strain-Dependent Differences In S. Sanguinis Virulence And Growth, Shannon Baker

Theses and Dissertations

Streptococcus sanguinis, an abundant and benign inhabitant of the oral cavity, is an important etiologic agent of infective endocarditis, particularly in people with pre-disposing cardiac valvular damage. Although commonly isolated from patients with IE, little is known about the factors that make any particular S. sanguinis isolate more virulent than another or, indeed, whether significant differences in virulence exist among isolates. To investigate the virulence of multiple isolates, a variation of the Bar-seq (barcode sequencing) method was employed. A conserved chromosomal site was identified for subsequent insertion of a barcode identifier, unique for each strain. Barcode insertion did not …

Endothelial Hspa12b Is A Novel Protein For The Preservation Of Cardiovascular Function In Polymicrobial Sepsis Via Exosome Mir-126, Xia Zhang

Electronic Theses and Dissertations

Sepsis is the most frequent cause of mortality in most intensive care units. Cardiovascular dysfunction is a major complication associated with sepsis, with high mortality rates up to 70%. Currently, there is no effective treatment approach for sepsis.

The integrity of the endothelium is fundamental for the homeostasis of the cardiovascular system. Sepsis induces endothelial cell injury which is the key factor for multiple organ failure. The increased expression of adhesion molecules and chemokines in endothelial cell promotes leukocytes infiltration into the tissue. The loss of tight junction proteins and increased permeability of the endothelial cells will provoke tissue hypoxia …