BACKGROUND: Capsule endoscopy (CE) allows for a non-invasive small bowel evaluation for a wide range of gastrointestinal (GI) symptoms and diseases. Capsule technology has been rapidly advancing over recent years, often improving image frequency and quality. The Pillcam SB3 (SB3) capsule is one such technology that offers an adaptive frame rate advantage over the previous versions of the capsule the Pillcam SB2 (SB2). Some have proposed that this improvement in capsule technology may lead to increased diagnostic yields; however, real world clinical data is currently lacking. AIM: To evaluate the clinically relevant findings of SB3 and SB2 capsules in a population of United States veterans. METHODS: A retrospective analysis of 260 consecutive CE studies was performed including 130 SB3 and 130 SB2 capsule studies. Recorded variables included: age, gender, type of capsule, body mass index, exam completion, inpatient status, opioid use, diabetes, quality of preparation, gastric transit time, small bowel transit time, indication, finding, and if the exam resulted in a change in clinical management. The primary outcome measured was the detection of clinically relevant findings between SB3 and SB2 capsules. RESULTS: Mean age of the study population was 67.1 ± 10.4 years and 94.2% of patients were male. Of these 28.1% were on opioid users. The most common indications for capsule procedure were occult GI bleeding (74.6%) and overt GI bleeding (14.6%). Rates of incomplete exam were similar between SB3 and SB2 groups (16.9% 9.2%, = 0.066). The overall rate of clinically relevant finding was 48.9% in our study. No significant difference was observed in SB3 SB2 capsules for clinically relevant findings (46.2% 51.5%, = 0.385) or change in clinical management (40.8% 50.0%, = 0.135). CONCLUSION: Our study found no significant difference in clinically relevant findings between SB3 and SB2 capsules.

Cannabis use may occur during pregnancy to alleviate symptoms of nausea, anxiety, and stress. However, fetal exposure to cannabinoids, such as THC and CBD, poses potential risks to neurodevelopment and long-term health outcomes. The endocannabinoid system (ECS) is involved in neurodevelopment and gastrointestinal (GI) homeostasis and responds to exogenous cannabinoids. This study aimed to investigate both the baseline development of the ECS in the GI tract and the effects of prenatal cannabis exposure on the development of gut-brain axis components and the ECS. Samples from outbred mice were collected at a set of developmentally important time points, ranging from embryonic day 14 to postnatal day 21. The localization of cannabinoid receptor 1 (CB1) expression was examined in the fetal and postnatal small intestine, and mRNA analysis was performed to evaluate changes in gene expression. Under normal conditions, components of the ECS display developmental regulation in the GI tract. A subset of pregnant mice was exposed to cannabis smoke daily, using a strain of cannabis containing high concentrations of THC, simulating ‘real world’ cannabis use. Exposure to cannabis prenatally revealed significant changes in biometric outcomes, and in the transcription of genes associated with the ECS, ENS development, barrier function, and serotonin signaling pathways. In addition, the onset of ambulation was delayed. These findings provide valuable insights into the developmental regulation of ECS during the prenatal period and highlight the potential risks associated with prenatal cannabis exposure, particularly in terms of gut-brain axis development. Further research is required to better understand the underlying mechanisms. / Thesis / Master of Science (MSc) / There have been growing reports of cannabis consumption during pregnancy, to relieve nausea, anxiety, and stress. However, compounds in cannabis, like THC and CBD, can pose risks to the baby's development and long-term health. This project studied how cannabis use during pregnancy affects gastrointestinal (GI) development, and communication between the GI system and the brain. The endocannabinoid system (ECS) plays a role in regulating the normal functioning of the GI tract and is influenced by cannabis compounds. By exposing pregnant mice to cannabis smoke, we observed significant changes in gene expression in the fetal intestine relating to the GI nervous system, the strength of the gut barrier, and various molecular signalling pathways. In addition, prenatally exposed mice had delayed walking ability. These findings highlight the potential risks of cannabis use during pregnancy on gut-brain axis development. Further research is needed to understand the mechanisms causing these disruptions.

Supplemental feeding of deer is a common management action. However, concentrating animals, as feeding does, is known to promote the transmission of disease. We examined how feeding alters three sources of disease: aflatoxins, gastrointestinal parasites, and ticks. To do this, we paired 79 feeder sites throughout Mississippi with ecologically-equivalent sites without feeders. Wildlife visitation increased at feeders compared to sites without feeders. For aflatoxins, we sampled during the summer and hunting season and found low prevalence and levels in feeders and bagged/bulk feed. The greater concern was environmental exposure to aflatoxins. All corn piles exposed to environmental contamination in July contained toxic levels of aflatoxins after eight days. The environmental load of gastrointestinal parasites was elevated for coccidia (4x) and strongylids (3x). Finally, feeding reduced the number of ticks at feeder sites, but did not alter the prevalence of tick-borne diseases within captured ticks compared to sites without feeders.

京都大学 / 新制・課程博士 / 博士(医学) / 甲第24970号 / 医博第5024号 / 新制||医||1069(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 中山 健夫, 教授 川上 浩司, 教授 大鶴 繁 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Trillions of microbes line the gastrointestinal tract to form the gut microbiome, a symbiotic organ whose supportive functions include energy production, immune homeostasis, and defense against pathogens. Disturbances to gut microbial composition, in turn, drive the pathogenesis of various metabolic, inflammatory, and carcinogenic diseases. Much effort has been dedicated to elucidating environmental triggers of gut dysbiosis, not the least of which is the consumption of medications. Antibiotics eradicate keystone commensals and enhance pathogenic behaviors of persisting pathobionts, whose resistance mechanisms can have off-target effects on human physiology and treatment response. Recent evidence indicates that the spectrum of antimicrobial compounds that disturb the gut microbiome extends far beyond traditional antibiotics, and includes commonly prescribed cardiovascular, neuropsychiatric, metabolic, and cancer medications. Although the capacity of non-antibiotic pharmaceuticals to induce gut dysbiosis is well appreciated, their impact on gut microbial function has not been studied systematically. Bacterial multi-omic profiling offers a cost-effective, high-throughput approach to understanding bacterial genetic responses to chemical perturbations, and how these functional changes might reciprocally impact relevant human phenotypes. Our laboratory, which houses a personal strain biobank of over 30,000 gut bacterial isolates spanning over 400 taxa, has established scalable pipelines for bacterial genomic and transcriptomic profiling that are readily applicable to diverse non-model gut microbes. We applied these methodologies to healthy fecal samples and bacterial isolates to elucidate strain-level responses to common pharmaceuticals with known gut microbiome associations. We first performed a gut microbiota transcriptomic screen of 19 representative fecal isolates against 20 top-prescribed orally delivered medications. Computational analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) revealed induction of pathways associated with metabolism and multidrug resistance, including upregulation of efflux machinery by lipid-lowering drugs, antidepressants and cardiovascular medications. We discovered many bacterial responses with clinical significance, which we computationally validated using clinical metagenomic datasets. Most importantly, we showed that statin-mediated overexpression of the AcrAB-TolC efflux pump generates collateral toxicity in dietary retinol and secondary bile acids, resulting in depletion of pump-containing Bacteroidales species from patient microbiomes. We next performed the first comprehensive screen for antimicrobial activity in cancer drugs by exposing three healthy fecal samples to a panel of 41 first-line cancer therapeutics. Using 16S-genomic profiling, we identified several members of the targeted kinase inhibitor (TKI) class that induced gut dysbiosis, including first-line hepatocellular carcinoma (HCC) treatment sorafenib. We profiled natural bacterial isolates exposed to different TKI HCC treatments, and again observed transcriptional induction of conserved multidrug efflux pumps. Adaptive evolution assays identified Resistance-Nodulation-Division (RND) efflux pumps as effectors of TKI resistance. Remarkably, we demonstrated that acquired TKI resistance in evolved Bacteroidales lineages generated strain-specific cross-resistances and collateral sensitivities to several unrelated antibiotics. Collectively, our work demonstrates the importance of profiling xenobiotic impacts on the gut microbial resistome, as bacterial adaptations to pharmaceutical toxicities can feed back onto microbiome communities and the human host to affect health outcomes.

The Attwater’s prairie-chicken (Tympanuchus cupido attwateri; APC) is a species of grouse native to Texas coastal prairies and is on the critically endangered species list as a result of habitat destruction and overhunting. All of the current populations were captively bred and released into the wild. Survivorship for released APCs is very low, and individuals seldom survive to reproduce in the wild. One factor contributing to this may be an alteration in the gut microbiota as a result of captivity. Factors potentially influencing the gut microbial composition in captivity include antibiotic therapy, stress, and a predominantly commercially formulated diet. Recent studies have begun to shed light on the importance of the host microbial endosymbionts. Antibiotic administration, stress, diet, age, genotype and other factors have been shown to influence microbial populations in the gastrointestinal tracts of many different vertebrates. Sequencing of 16S rRNA gene amplicons on the Ion Torrent™ platform was used in this study to identify groups of bacteria in the cloacas as a surrogate for the gut microbiota in the APC. Antibiotic-treated and untreated birds, wild-hatched and captive-bred birds, and individuals sampled before and after release to the wild were examined. Significant differences were found between wild-hatched and captive raised birds both pre- and post release. In addition, there was extensive variation among the populations at the lower taxonomic ranks between individuals for each group of APCs. Principal coordinate analysis based on the weighted UniFrac distance metric further exhibited some clustering of individuals by treatment. These data suggest that captive breeding may have long-term effects on the cloacal microbiota of APCs with unknown consequences to their long-term health and survivorship.

No description available.

Helicobacter pylori (H. pylori) is a Gram-negative bacterium that infects and resides in the gastric mucosa of humans. Without treatment, H. pylori infection may cause chronic inflammation of the gastric mucosa. This inflammation creates progressive damage to the lining of the stomach and can lead to multiple diseases located in the upper gastrointestinal region. Worldwide prevalence of H. pylori infection is estimated to be close to 50%. H. pylori has been identified as the primary cause of peptic ulcer disease, gastric cancer, and mucosa-associated lymphoid tissue lymphoma. The purpose of this study was to identify the prevalence and risk factors associated with H. pylori infection among students, faculty, and staff at the University of Central Florida. A cross-sectional design with a convenience sample was implemented to acquire a study population of 60 participants. The sample was analyzed through the use of a twenty question survey and a rapid blood antibody test kit. The infection rate of the sample was 1.75%. Statistically significant results were found for the relationship between age and upper gastrointestinal symptoms. Trends were also noticed between alcohol consumption, stress levels, and upper gastrointestinal symptoms.

No description available.

No description available.