Digestive System Commons^™

The Relationship Between Problem-Solving Ability/Eating Motivation And Perceived Quality Of Life In Individuals Diagnosed With Celiac Disease, Vincenzo Zaccheo

PCOM Psychology Dissertations

Celiac disease (CD) is a digestive disorder resulting from gluten intolerance that leads to damage of the small intestine. The only current available treatment for CD involves adherence to a strict gluten-free diet. Due to the restrictive nature of this treatment diet, and the increasing prevalence of CD in recent years, much research has been conducted examining factors that impact the quality of life (QOL) of individuals with CD. However, there has been a dearth of literature identifying those factors which can be modified within a treatment setting. Thus, a need for further research in this area was identified. Through …

Relating The Metatranscriptome And Metagenome Of The Human Gut, Eric A. Franzosa, Xochitl C. Morgan, Nicola Segata, Levi Waldron, Joshua Reyes, Ashlee M. Earl, Georgia Giannoukos, Matthew R. Boylan, Dawn Ciulla, Dirk Gevers, Jacques Izard, Wendy S. Garrett, Andrew T. Chan, Curtis Huttenhower

Department of Food Science and Technology: Faculty Publications

Although the composition of the human microbiome is now well-studied, the microbiota’s > 8 million genes and their regulation remain largely uncharacterized. This knowledge gap is in part because of the difficulty of acquiring large numbers of samples amenable to functional studies of the microbiota. We conducted what is, to our knowledge, one of the first human microbiome studies in a well-phenotyped prospective cohort incorporating taxonomic, metagenomic, and metatranscriptomic profiling at multiple body sites using self-collected samples. Stool and saliva were provided by eight healthy subjects, with the former preserved by three different methods (freezing, ethanol, and RNAlater) to validate self-collection. …

Mast Cell Activation And Clinical Outcome In Pediatric Cholelithiasis And Biliary Dyskinesia., Craig A. Friesen, Nancy Neilan, James F. Daniel, Kim Radford, Jennifer Verrill Schurman, Ding-You Li, Linda Andre, Shawn D. St Peter, G W. Holcomb Iii

Manuscripts, Articles, Book Chapters and Other Papers

BACKGROUND: The current study was undertaken to determine the degree of activation of gallbladder mucosal mast cells, whether mast cell (MC) density or activation differ between patients with and without a positive clinical response to cholecystectomy, and whether either density or activation correlate with gallbladder emptying.

RESULTS: Fifteen biliary dyskinesia (BD) and 13 symptomatic cholelithiasis (CL) patients undergoing cholecystectomy were prospectively enrolled. Gallbladder wall MC density (by immunohistochemistry) and activation (by electron microscopy) were determined. Clinical response was evaluated 30 days post-cholecystectomy on a 5-point Likert-type scale. A complete or nearly complete clinical response was seen in 100% of CL …

Protection And Attachment Of Vibrio Cholerae Mediated By The Toxin-Coregulated Pilus In The Infant Mouse Model, Shelly J. Krebs, Ronald K. Taylor

Dartmouth Scholarship

Colonization of the human small intestine by Vibrio cholerae is an essential step in pathogenesis that requires the type IV toxin-coregulated pilus (TCP). To date, three functions of TCP have been characterized: it serves as the CTXΦ receptor, secretes the colonization factor TcpF, and functions in microcolony formation by mediating bacterium-bacterium interactions. Although type IV pili in other pathogenic bacteria have been characterized as playing a major role in attachment to epithelial cells, there are very few studies to suggest that TCP acts as an attachment factor. Taking this into consideration, we investigated the function of TCP in attachment to …

Levels Of The Secreted Vibrio Cholerae Attachment Factor Gbpa Are Modulated By Quorum-Sensing-Induced Proteolysis, Brooke A. Jude, Raquel M. Martinez, Karen Skorupski, Ronald K. Taylor

Dartmouth Scholarship

Vibrio cholerae is the etiologic agent of cholera in humans. Intestinal colonization occurs in a stepwise fashion, initiating with attachment to the small intestinal epithelium. This attachment is followed by expression of the toxin-coregulated pilus, microcolony formation, and cholera toxin (CT) production. We have recently characterized a secreted attachment factor, GlcNAc binding protein A (GbpA), which functions in attachment to environmental chitin sources as well as to intestinal substrates. Studies have been initiated to define the regulatory network involved in GbpA induction. At low cell density, GbpA was detected in the culture supernatant of all wild-type (WT) strains examined. In …

Liquid Chromatography-Tandem Mass Spectrometry For The Determination Of Methylprednisolone In Rat Plasma And Liver After Intravenous Administration Of Its Liver-Targeted Dextran Prodrug, Shuang-Qing Zhang, Helen R. Thorsheim, Suman Penugonda, Venkateswaran C. Pillai, Quentin R. Smith, Reza Mehvar

Pharmacy Faculty Articles and Research

A specific and sensitive liquid chromatography (LC)-tandem mass spectrometric method for quantitative determination of methylprednisolone (MP) in rat plasma and liver was developed and validated using triamcinolone acetonide as an internal standard. Liquid-liquid extraction using tert-butyl methyl ether was used to extract the drug and the internal standard from plasma and liver. The separation of MP was performed on a C(18) column with a mobile phase of acetonitrile:0.5% formic acid aqueous solution (85:15, v/v) over 4 min. The assay was based on the selected reaction monitoring transitions at m/z 375 -> 161 for MP in plasma, 375 -> 357 for …

The Nestin Progenitor Lineage Is The Compartment Of Origin For Pancreatic Intraepithelial Neoplasia, Catherine Carriere, Elliot S. Seeley, Tobias Goetze, Daniel S. Longnecker, Murray Korc

Dartmouth Scholarship

To determine the cell compartment in which initial oncogenic mutations occur in pancreatic ductal adenocarcinoma (PDAC), we generated a mouse model in which endogenous expression of mutated Kras (Kras(G12D)) was initially directed to a population of pancreatic exocrine progenitors characterized by the expression of Nestin. Targeting of oncogenic Kras to such a restricted cell compartment was sufficient for the formation of pancreatic intraepithelial neoplasias (PanINs), putative precursors to PDAC. PanINs appeared with the same grade and frequency as observed when Kras(G12D) was targeted to the whole pancreas by a Pdx1-driven Cre recombinase strategy. Thus, the Nestin cell lineage is highly …

Rapid Determination Of Reduced And Oxidized Glutathione Levels Using A New Thiol-Masking Reagent And The Enzymatic Recycling Method: Application To The Rat Liver And Bile Samples, Imam H. Shaik, Reza Mehvar

Pharmacy Faculty Articles and Research

A microtiter plate assay for quantitation of reduced (GSH) and oxidized (GSSG) glutathione in the rat liver tissue and bile is described. The assay is based on the established enzymatic recycling method and a new thiol-masking reagent, 1-methyl-4-vinyl-pyridinium trifluoromethane sulfonate (M4VP). Samples were first processed by homogenization with (liver) or addition of (bile) sulfosalicylic acid. The total glutathione and GSSG were then determined before and after rapid (>= 2 min) and efficient (100%) masking of the GSH content of the samples with M4VP followed by the enzymatic recycling assay. The percentages of error and coefficient of variation of the …

Tcpf Is A Soluble Colonization Factor And Protective Antigen Secreted By El Tor And Classical O1 And O139 Vibrio Cholerae Serogroups, Thomas J. Kirn, Ronald K. Taylor

Dartmouth Scholarship

Vibrio cholerae causes diarrhea by colonizing the human small bowel and intoxicating epithelial cells. Colonization is a required step in pathogenesis, and strains defective for colonization are significantly attenuated. The best-characterized V. cholerae colonization factor is the toxin-coregulated pilus (TCP). It has been demonstrated that TCP is required for V. cholerae colonization in both humans and mice. TCP enhances bacterial interactions that allow microcolony formation and thereby promotes survival in the intestine. We have recently discovered that the TCP biogenesis apparatus also serves as a secretion system, mediating the terminal step in the extracellular secretion pathway of TcpF. TcpF was …

Hepatic Disposition Of Cyclosporine A In Isolated Perfused Rat Livers, Reza Mehvar, Anjaneya Chimalakonda

Pharmacy Faculty Articles and Research

PURPOSE. To develop an isolated perfused rat liver model to study the hepatic disposition of cyclosporine A (CyA) in both sexes.

METHODS. Livers were isolated from male (n = 6) and female (n = 7) rats and perfused with a physiological buffer in a single-pass manner. A bolus 1-mg dose of CyA was injected into the inlet catheter and periodical samples (0-15 min) were collected from the outlet perfusate. The concentrations of CyA in the outlet perfusate, collected bile (0-15 min), and liver tissue (at the end of perfusion) were quantitated by HPLC and subjected to statistical moment analysis. …

Anti-Class Ii Monoclonal Antibody-Targeted Vibrio Cholerae Tcpa Pilin: Modulation Of Serologic Response, Epitope Specificity, And Isotype, Jia-Yan Wu, Ronald K. Taylor, William F. Wade

Dartmouth Scholarship

Toxin-coregulated pilus (TCP) is a colonization factor required for cholera infection. It is not a strong immunogen when delivered in the context of whole cells, yet pilus subunits or TcpA derivative synthetic peptides induce protective responses. We examined the efficacy of immunizing mice with TCP conjugated to anti-class II monoclonal antibodies (MAb) with or without the addition of cholera toxin (CT) or anti-CD40 MAb to determine if the serologic response to TcpA could be manipulated. Anti-class II MAb-targeted TCP influenced the anti-TCP peptide serologic response with respect to titer and isotype. Responses to TcpA peptide 4 were induced with class …

Ups And Downs Of Mucosal Cellular Immunity Against Protozoan Parasites, Lloyd H. Kasper, Dominique Buzoni-Gatel

Dartmouth Scholarship

No abstract provided.

Toxin-Coregulated Pilus, But Not Mannose-Sensitive Hemagglutinin, Is Required For Colonization By Vibrio Cholerae O1 El Tor Biotype And O139 Strains., K Helene Thelin, Ronald K. Taylor

Dartmouth Scholarship

The relative contributions of toxin-coregulated pilus (TCP) and cell-associated mannose-sensitive hemagglutinin (MSHA) to the colonization ability of Vibrio cholerae O1 El Tor biotype strains and O139 Bengal strains was determined by using isogenic parental and in-frame deletion mutant pairs in the infant mouse cholera model. Both the El Tor and O139 tcpA mutant strains showed a dramatic defect in colonization as indicated by their competitive indices, whereas deletion of mshA had a negligible effect on colonization in either background.