Life Sciences Commons^™

Mechanism By Which Commensal Bacteria Limit Inflammation, Mallory Paynich

Dissertations

Trillions of bacteria live within the gastrointestinal tract and are critical for maintaining intestinal homeostasis; however, the mechanisms utilized by specific bacterial molecules to contribute to homeostasis are not well understood. We utilize a mouse model in which a single oral dose of the probiotic, Bacillus subtilis, protects mice from acute colitis induced by the enteric pathogen Citrobacter rodentium. Our goal is to elucidate the mechanism by which B. subtilis prevents inflammation.

We identified exopolysaccharides (EPS) to be the active molecule of B. subtilis, and a single dose of EPS protects mice from disease. EPS binds F4/80+CD11b+ peritoneal macrophages, and …

Role Of The Intestinal Microbiota In Gut Barrier Dysfunction Following Burn Injury, Zachary Earley

Master's Theses

Burn injury represents a major medical problem with half a million cases requiring medical attention and 4,000 deaths reported annually. Sepsis and multiple organ failure remain the leading causes of death following injury, and may be brought on by bacterial infections or toxins. The gastrointestinal tract contains approx. 100 trillion microbes; therefore, the indigenous commensal microbiota may play a role in leading to these complications or infections in burn patients. The overall objective of this project is to identify a potential mechanism whereby changes in gut bacteria may lead to intestinal inflammation or bacterial translocation--key factors which may lead to …

Urinary Antimicrobial Peptides And The Urinary Microbiota In A Uti-Susceptible Population Of Female Pelvic Floor Surgery Patients, Vanessa Nienhouse

Master's Theses

Urinary tract infections (UTI)s are a national priority. Women who undergo surgery for pelvic floor disorders such as pelvic organ prolapse (POP) or urinary incontinence (UI) are at increased risk for UTI, as 10-30% will contract a post-instrumentation UTI (postI-UTI) within six weeks after surgery. Currently, the factors that contribute to the high rate of postI-UTI are unknown, and there is currently no clinical assessment to identify at-risk patients. However, antimicrobial peptides (AMPs) and characteristics of the urinary microbiota have the potential to serve as biomarkers, identifying patients at UTI risk and facilitating clinical prevention studies.

While it was previously …