DNA methylation-associated colonic mucosal immune and defense responses in treatment-naïve pediatric ulcerative colitis

Inflammatory bowel diseases (IBD) are emerging globally, indicating that environmental factors may be important in their pathogenesis. Colonic mucosal epigenetic changes, such as DNA methylation, can occur in response to the environment and have been implicated in IBD pathology. However, mucosal DNA methylation has not been examined in treatment-naïve patients. We studied DNA methylation in untreated, left sided colonic biopsy specimens using the Infinium HumanMethylation450 BeadChip array. We analyzed 22 control (C) patients, 15 untreated Crohn’s disease (CD) patients, and 9 untreated ulcerative colitis (UC) patients from two cohorts. Samples obtained at the time of clinical remission from two of the treatment-naïve UC patients were also included into the analysis. UC-specific gene expression was interrogated in a subset of adjacent samples (5 C and 5 UC) using the Affymetrix GeneChip PrimeView Human Gene Expression Arrays. Only treatment-naïve UC separated from control. One-hundred-and-twenty genes with significant expression change in UC (> 2-fold, P < 0.05) were associated with differentially methylated regions (DMRs). Epigenetically associated gene expression changes (including gene expression changes in the IFITM1, ITGB2, S100A9, SLPI, SAA1, and STAT3 genes) were linked to colonic mucosal immune and defense responses. These findings underscore the relationship between epigenetic changes and inflammation in pediatric treatment-naïve UC and may have potential etiologic, diagnostic, and therapeutic relevance for IBD

Fungal dysbiosis predicts the diagnosis of pediatric Crohn's disease

AIM: To investigate the accuracy of fungal dysbiosis in mucosa and stool for predicting the diagnosis of Crohn’s disease (CD). METHODS: Children were prospectively enrolled in two medical centers: one university hospital and one private gastroenterology clinic in the city of Riyadh, Kingdom of Saudi Arabia. The children with confirmed diagnosis of CD by standard guidelines were considered cases, and the others were considered non-inflammatory bowel disease controls. Mucosal and stool samples were sequenced utilizing Illumina MiSeq chemistry following the manufacturer’s protocols, and abundance and diversity of fungal taxa in mucosa and stool were analyzed. Sparse logistic regression was used to predict the diagnosis of CD. The accuracy of the classifier was tested by computing the receiver operating characteristic curves with 5-fold stratified cross-validation under 100 permutations of the training data partition and the mean area under the curve (AUC) was calculated. RESULTS: All the children were Saudi nationals. There were 15 children with CD and 20 controls. The mean age was 13.9 (range: 6.7-17.8) years for CD children and 13.9 (3.25-18.6) years for controls, and 10/15 (67%) of the CD and 13/20 (65%) of the control subjects were boys. CD locations at diagnosis were ileal (L1) in 4 and colonic (L3) in 11 children, while CD behavior was non-stricturing and non-penetrating (B1) in 12 and stricturing (B2) in 3 children. The mean AUC for the fungal dysbiosis classifier was significantly higher in stools (AUC = 0.85 ± 0.057) than in mucosa (AUC = 0.71 ± 0.067) (P < 0.001). Most fungal species were significantly more depleted in stools than mucosal samples, except for Saccharomyces cerevisiae and S. bayanus, which were significantly more abundant. Diversity was significantly more reduced in stools than in mucosa. CONCLUSION: We found high AUC of fungal dysbiosis in fecal samples of children with CD, suggesting high accuracy in predicting diagnosis of CD. Key Words: Fungiome, Mycobiome, Crohn’s disease, Inflammation, Saudi children Core tip: We found high accuracy of fungal dysbiosis in predicting diagnosis of Crohn’s disease (CD), a finding similar to bacterial dysbiosis. However, the higher area under the curve for the fungal dysbiosis classifier in stool (0.85 ± 0.057) than in mucosa (0.71 ± 0.067) (P < 0.001), contrasts with bacterial studies, suggesting higher accuracy of stool samples. Although the clinical application of this finding is limited at present by the high cost of fungal analysis, such information is important from a scientific viewpoint, to increase the understanding of the role of fungal flora in CD and to stimulate further studies.The authors extend their appreciations to the Deanship of Scientific Research at King Saud University in Riyadh, Kingdom of Saudi Arabia for funding this work through Research Group No [RGP-1436-007]. This work was also supported by a grant from the Simons Foundation [No. 409704] to Kirill Korolev) and by the startup fund from Boston University to Kirill Korolev. Simulations were carried out on Shared Computing Cluster at Boston University. Rajita Menon was partially supported by a Hariri Graduate Fellowship from Boston University. Harland Winter, MD received support from Martin Schlaff and the Diane and Dorothy Brooks Foundation. (RGP-1436-007 - King Saud University in Riyadh, Kingdom of Saudi Arabia; 409704 - Simons Foundation; Boston University; Hariri Graduate Fellowship from Boston University; Diane and Dorothy Brooks Foundation)Published versio

MicroRNA-124 Regulates STAT3 Expression and Is Down-regulated in Colon Tissues of Pediatric Patients With Ulcerative Colitis

Background & Aims - Altered levels and functions of microRNAs (miRs) have been associated with inflammatory bowel diseases (IBDs), although little is known about their roles in pediatric IBD. We investigated whether colonic mucosal miRs are altered in children with ulcerative colitis (UC). Methods - We used a library of 316 miRs to identify those that regulate phosphorylation of STAT3 in NCM460 human colonocytes incubated with interleukin-6. Levels of miR-124 were measured by real-time PCR analysis of colon biopsies from pediatric and adult patients with UC and patients without IBD (controls), and of HCT-116 colonocytes incubated with 5-aza-2’-deoxycytidine. Methylation of the MIR124 promoter was measured by quantitative methylation-specific PCR. Results - Levels of phosphorylated STAT3 and the genes it regulates (encoding VEGF, BCL2, BCLXL, and MMP9) were increased in pediatric patients with UC, compared to control tissues. Overexpression of miR-124, let-7, miR-125, miR-26, or miR-101 reduced STAT3 phosphorylation by ≥75% in NCM460 cells; miR-124 had the greatest effect. miR-124 was downregulated specifically in colon tissues from pediatric patients with UC and directly targeted STAT3 mRNA. Levels of miR-124 were decreased whereas levels of STAT3 phosphorylation increased in colon tissues from pediatric patients with active UC, compared to those with inactive disease. Furthermore, levels of miR-124 and STAT3 were inversely correlated in mice with experimental colitis. Downregulation of miR-124 in tissues from children with UC was attributed to hypermethylation of its promoter region. Incubation of HCT-116 colonocytes with 5-aza-2’ deoxycytidine upregulated miR-124 and reduced levels of STAT3 mRNA. Conclusions - MiR-124 appears to regulate the expression of STAT3. Reduced levels of miR-124 in colon tissues of children with active UC appear to increase expression and activity of STAT3, which could promote inflammation and pathogenesis of UC in children

Multi-omics of the gut microbial ecosystem in inflammatory bowel diseases.

Inflammatory bowel diseases, which include Crohn's disease and ulcerative colitis, affect several million individuals worldwide. Crohn's disease and ulcerative colitis are complex diseases that are heterogeneous at the clinical, immunological, molecular, genetic, and microbial levels. Individual contributing factors have been the focus of extensive research. As part of the Integrative Human Microbiome Project (HMP2 or iHMP), we followed 132 subjects for one year each to generate integrated longitudinal molecular profiles of host and microbial activity during disease (up to 24 time points each; in total 2,965 stool, biopsy, and blood specimens). Here we present the results, which provide a comprehensive view of functional dysbiosis in the gut microbiome during inflammatory bowel disease activity. We demonstrate a characteristic increase in facultative anaerobes at the expense of obligate anaerobes, as well as molecular disruptions in microbial transcription (for example, among clostridia), metabolite pools (acylcarnitines, bile acids, and short-chain fatty acids), and levels of antibodies in host serum. Periods of disease activity were also marked by increases in temporal variability, with characteristic taxonomic, functional, and biochemical shifts. Finally, integrative analysis identified microbial, biochemical, and host factors central to this dysregulation. The study's infrastructure resources, results, and data, which are available through the Inflammatory Bowel Disease Multi'omics Database ( http://ibdmdb.org ), provide the most comprehensive description to date of host and microbial activities in inflammatory bowel diseases

Case 27-2011: A 17-Year-Old Boy with Abdominal Pain and Weight Loss

Pr e sen tat ion of C a se Dr. Nina Mayer (Medicine-Pediatrics): A 17-year-old boy was seen in the pediatric gastroenterology clinic of this hospital because of abdominal pain and weight loss. The patient had been well until approximately 6 weeks earlier, when intermittent crampy abdominal pain developed. Approximately 3 weeks later, nonbloody diarrhea developed and lasted for a week, associated with one episode of emesis. Thereafter, abdominal pain occurred daily, was predominantly located in the right lower quadrant, radiated to the right flank, and was associated with lower back discomfort, borborygmi, and constipation. During the fourth week of illness, after the diarrhea had resolved, the patient saw his primary care physician. Serum levels of glucose, alanine aminotransferase, and thyrotropin were normal, as were tests of renal function. Tests for tissue transglutaminase IgA antibodies, hepatitis A virus, hepatitis C virus, and the human immunodeficiency virus (HIV) were negative. Results of tests for serum antibodies to Epstein-Barr virus (EBV) were consistent with past infection; testing was positive for hepatitis B virus surface antibody and negative for hepatitis B surface antigen, indicating immunity or past infection. Other results are shown in Two weeks later, the patient was seen in the pediatric gastroenterology clinic at this hospital. He rated the abdominal pain at 5 on a scale of 0 to 10, with 10 indicating the most severe pain. He reported one bowel movement of hard stool daily, and one episode of blood streaking on the stool after straining, with no mucus. He reported that he had lost 18.2 kg during the previous 2 years. The first 11 to 12 kg was intentional; however, during the 6 weeks before this evaluation, additional weight loss had occurred unintentionally. The body-mass index (the weight in kilograms divided by the square of the height in meters) had reportedly decreased from 27.0 (&gt;95th percentile for his age) to 20.5 (25th to 50th percentile). He reported night sweats with chills but no fever. The patient had visited relatives in Haiti approximately 4 years earlier for 1 week; he reported no exposure to persons with respiratory or gastrointestinal symptoms while there or recently. Skin tests for tuberculosis were reportedly negative befor

Surgical Management of Crohn Disease in Children: Guidelines From the Paediatric IBD Porto Group of ESPGHAN

The incidence of Crohn disease (CD) has been increasing and surgery needs to be contemplated in a substantial number of cases. The relevant advent of biological treatment has changed but not eliminated the need for surgery in many patients. Despite previous publications on the indications for surgery in CD, there was a need for a comprehensive review of existing evidence on the role of elective surgery and options in pediatric patients affected with CD. We present an expert opinion and critical review of the literature to provide evidence-based guidance to manage these patients. Indications, surgical options, risk factors, and medications in pre-and perioperative period are reviewed in the light of available evidence. Risks and benefits of surgical options are addressed. An algorithm is proposed for the management of postsurgery monitoring, timing for follow-up endoscopy, and treatment options

Academic Arrhythmia: Disruption, Dissonance and Conflict in the Early-Career Rhythms of CMS Academics

Starting a career on the margins of the neoliberal business school is becoming increasingly challenging. We contribute to the understanding of the problems involved and to potential solutions by developing a theoretically-informed approach to the rhythms of academic life and drawing on interviews with 32 Critical Management Studies (CMS) early-career academics (ECAs) in 14 countries. Bringing together Lefebvre’s rhythmanalysis (and his concepts of polyrhythmia, eurhythmia and arrhythmia), Zerubavel’s sociology of time, and identity construction literature, we examine the rhythm-identity implications of the recent HE changes. We show how the dynamics between the broader pressures, institutional strategies, and our interviewees’ attempts to reassert themselves are creating a vicious circle of arrhythmia – a debilitating condition characterized by rhythmic disruption, dissonance and conflict. Within the circle, identity insecurity and regulation, CMS ECAs’ identity work, and arrhythmia are mutually co-constructive, so that it is hard for individuals to break out. We consider the possibilities and limitations of individual coping strategies and, drawing out lessons for business schools, advocate for more collective and structural solutions. In so doing, we contribute to the reimagining of business schools as more eurhythmically polyrhythmic places where ECAs of all intellectual orientations have the time to learn and develop

Calfacilitin is a calcium channel modulator essential for initiation of neural plate development.

Calcium fluxes have been implicated in the specification of the vertebrate embryonic nervous system for some time, but how these fluxes are regulated and how they relate to the rest of the neural induction cascade is unknown. Here we describe Calfacilitin, a transmembrane calcium channel facilitator that increases calcium flux by generating a larger window current and slowing inactivation of the L-type CaV1.2 channel. Calfacilitin binds to this channel and is co-expressed with it in the embryo. Regulation of intracellular calcium by Calfacilitin is required for expression of the neural plate specifiers Geminin and Sox2 and for neural plate formation. Loss-of-function of Calfacilitin can be rescued by ionomycin, which increases intracellular calcium. Our results elucidate the role of calcium fluxes in early neural development and uncover a new factor in the modulation of calcium signalling

Measurement of the cross section for isolated-photon plus jet production in pp collisions at √s=13 TeV using the ATLAS detector

The dynamics of isolated-photon production in association with a jet in proton–proton collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset with an integrated luminosity of 3.2 fb−1. Photons are required to have transverse energies above 125 GeV. Jets are identified using the anti- algorithm with radius parameter and required to have transverse momenta above 100 GeV. Measurements of isolated-photon plus jet cross sections are presented as functions of the leading-photon transverse energy, the leading-jet transverse momentum, the azimuthal angular separation between the photon and the jet, the photon–jet invariant mass and the scattering angle in the photon–jet centre-of-mass system. Tree-level plus parton-shower predictions from Sherpa and Pythia as well as next-to-leading-order QCD predictions from Jetphox and Sherpa are compared to the measurements