Transcription and DNA Methylation Patterns of Blood-Derived CD8+ T Cells Are Associated With Age and Inflammatory Bowel Disease But Do Not Predict Prognosis.

BACKGROUND & AIMS: Gene expression patterns of CD8+ T cells have been reported to correlate with clinical outcomes of adults with inflammatory bowel diseases (IBD). We aimed to validate these findings in independent patient cohorts. METHODS: We obtained peripheral blood samples from 112 children with a new diagnosis of IBD (71 with Crohn's disease and 41 with ulcerative colitis) and 19 children without IBD (controls) and recorded medical information on disease activity and outcomes. CD8+ T cells were isolated from blood samples by magnetic bead sorting at the point of diagnosis and during the course of disease. Genome-wide transcription (n = 192) and DNA methylation (n = 66) profiles were generated using Affymetrix and Illumina arrays, respectively. Publicly available transcriptomes and DNA methylomes of CD8+ T cells from 3 adult patient cohorts with and without IBD were included in data analyses. RESULTS: Previously reported CD8+ T-cell prognostic expression and exhaustion signatures were only found in the original adult IBD patient cohort. These signatures could not be detected in either a pediatric or a second adult IBD cohort. In contrast, an association between CD8+ T-cell gene expression with age and sex was detected across all 3 cohorts. CD8+ gene transcription was clearly associated with IBD in the 2 cohorts that included non-IBD controls. Lastly, DNA methylation profiles of CD8+ T cells from children with Crohn's disease correlated with age but not with disease outcome. CONCLUSIONS: We were unable to validate previously reported findings of an association between CD8+ T-cell gene transcription and disease outcome in IBD. Our findings reveal the challenges of developing prognostic biomarkers for patients with IBD and the importance of their validation in large, independent cohorts before clinical application.

A content analysis of 'Water Apps' and prevention of urological diseases: Do apps really help?

INTRODUCTION: Maintaining hydration reduces incidence of kidney stone disease (KSD), chronic kidney disease (CKD) and urinary tract infections (UTIs). Mobile applications (apps) measuring hydration are gaining in usage, allowing users to monitor intake whilst also taking into account the signs and symptoms of dehydration. Our study looked at the water apps in the management and/or prevention of urological disease. MATERIAL AND METHODS: The original android app store (Google Play Store), and the Apple App Store (iOS App Store) were searched using the term 'hydration', 'fluid' and 'water'. All apps from each distribution platform, with a minimum of 100 reviews, were then selected and analysed. RESULTS: After identification of 51 applications (13 from Apple App Store, and 38 from Google Play Store), 45 were free to download and 6 were paid (cost range: $2.19-$7.97). While none of the apps facilitated measurement of urine output and colour, 12 mentioned signs and symptoms of dehydration. Furthermore, when calculating required fluid intake, the level of activity was considered by 31 apps. With regards to information provision, only one of the apps included advice or education about urological conditions associated with poor hydration. None of the apps gave advice on hydration related to CKD and UTI. CONCLUSIONS: Mobile phone apps are a well-established tool for measuring fluid intake. However, they provide little information regarding the importance of hydration, and don't utilise other measures such as level of activity, urine output or colour. Considering the increasing popularity of fitness and hydration apps in our daily lives, the developers need to make them more comprehensive and informative.