Browsing by Author "Robin D. Gleed"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • No Thumbnail Available
    PublicationMetadata only
    Clostridium difficile transcriptome analysis using pig ligated loop model reveals modulation of pathways not modulated in vitro
    (2011-06-01) Joy Scaria; Tavan Janvilisri; Susan Fubini; Robin D. Gleed; Sean P. McDonough; Yung Fu Chang; Cornell University; Mahidol University
    A pig ligated loop model was used to analyze the in vivo transcriptome response of Clostridium difficile. Bacterial RNA from the loops was retrieved at different times and was used for microarray analysis. Several virulence-associated genes and genes involved in sporulation cascade were differentially expressed (DE). In concordance with observed upregulation of toxin genes in microarray, enzyme-linked immunosorbent assay estimation of total toxin showed high amounts of toxin in the loops. Several genes that were absent in primary annotation of C. difficile 630 but annotated in a secondary annotation were found to be DE. Pathway c omparison of DE genes in vitro and in vivo showed that when several pathways were expressed in all conditions, several of the C. difficile pathways were uniquely expressed only in vivo. The pathways observed to be modulated only in this study could be targets of new therapeutic agents against C. difficile infection. © The Author 2011. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved.
  • No Thumbnail Available
    PublicationMetadata only
    Temporal Differential Proteomes of Clostridium difficile in the Pig Ileal-Ligated Loop Model
    (2012-09-18) Tavan Janvilisri; Joy Scaria; Ching Hao Teng; Sean P. McDonough; Robin D. Gleed; Susan L. Fubini; Sheng Zhang; Bruce Akey; Yung Fu Chang; Cornell University; Mahidol University; National Cheng Kung University Medical College
    The impact of Clostridium difficile infection (CDI) on healthcare is becoming increasingly recognized as it represents a major cause of nosocomial diarrhea. A rising number of CDI cases and outbreaks have been reported worldwide. Here, we developed the pig ileal-ligated loop model for semi-quantitative analysis comparing temporal differential proteomes in C. difficile following in vivo incubation with in vitro growth using isobaric tags for relative and absolute quantification (iTRAQ). Proteins retrieved from the in vitro cultures and the loop contents after 4, 8, and 12 h in vivo incubation were subjected to in-solution digestion, iTRAQ labeling, two-dimensional liquid chromatography/tandem mass spectrometry and statistical analyses. From a total of 1152 distinct proteins identified in this study, 705 proteins were available for quantitative measures at all time points in both biological and technical replicates; 109 proteins were found to be differentially expressed. With analysis of clusters of orthologous group and protein-protein network interactions, we identified the proteins that might play roles in adaptive responses to the host environment, hence enhancing pathogenicity during CDI. This report represents the quantitative proteomic analysis of C. difficile that demonstrates time-dependent protein expression changes under conditions that mimic in vivo infection and identifies potential candidates for diagnostic or therapeutic measures. © 2012 Janvilisri et al.