Now showing 1 - 2 of 2
  • Publication
    Investigation of facilitative urea transporters in the human gastrointestinal tract
    The symbiotic relationship between humans and their intestinal microbiomeis supported by urea nitrogen salvaging. Previous studies have shown thatcolonic UT-B urea transporters play a significant role in this important physi-ological process. This current study investigated UT-A and UT-B urea trans-porter expression along the human gastrointestinal tract. Initial end-pointPCR experiments determined that UT-A RNA was predominantly expressedin the small intestine, while UT-B RNA was expressed in stomach, small intes-tine, and colon. Using western blotting experiments, a strong 40–60 kDa UT-B signal was found to be abundant in both ileum and colon. Importantly, thissignal was deglycosylated by PNGaseF enzyme treatment to a core protein of30 kDa in both tissues. Further immunolocalization studies revealed UT-Btransporter proteins were present at the apical membrane of the villi in theileum, but predominantly at the basolateral membrane of the colonic surfaceepithelial cells. Finally, a blind scoring immunolocalization study suggestedthat there was no significant difference in UT-B abundance throughout thecolon (NS, ANOVA,N=5–21). In conclusion, this current study suggestedUT-B to be the main human intestinal urea transporter. Intriguingly, thesedata suggested that the same UT-B isoform was present in all intestinalepithelial cells, but that the precise cellular location varied.
      261Scopus© Citations 5
  • Publication
    Examining gender effects in different types of undergraduate science assessment
    The optimum assessment structure measures student knowledge accurately and without bias. In this study, the performance of the first-year undergraduate science students from the University College Dublin was evaluated to test the gender equality of the assessment structure in place. Results of male and female students taking three life science modules were analysed, for two academic years, with assessment structure based on a combination of three types of evaluation: continuous assessment and multiple choice questions (MCQ) exam scored with/without negative marking. We found no significant gender effect associated with performance in continuous assessment, or MCQ exams scored without negative marking. However, a significant bias against females was consistently observed for the same cohort of students in the MCQ exams with negative marking of 0.25 points. This bias was at least partially linked to a gender difference in willingness to guess and preliminary data suggest that it disappears after removal of negative marking from the MCQ exams. Our results support the view of a diverse assessment structure being fairer to the students. Moreover, caution is advised while using negative marking, and regular reviews of assessment strategy should be implemented by higher education institutions to ensure gender-bias free evaluation of students’ performance.
      84Scopus© Citations 3