134 research outputs found
Loss of Hepatocyte-Nuclear-Factor-4α Affects Colonic Ion Transport and Causes Chronic Inflammation Resembling Inflammatory Bowel Disease in Mice
BACKGROUND: Hnf4alpha, an epithelial specific transcriptional regulator, is decreased in inflammatory bowel disease and protects against chemically-induced colitis in mice. However, the precise role of this factor in maintaining normal inflammatory homeostasis of the intestine remains unclear. The aim of this study was to evaluate the sole role of epithelial Hnf4alpha in the maintenance of gut inflammatory homeostasis in mice. METHODOLOGY/PRINCIPAL FINDINGS: We show here that specific epithelial deletion of Hnf4alpha in mice causes spontaneous chronic intestinal inflammation leading to focal areas of crypt dropout, increased cytokines and chemokines secretion, immune cell infiltrates and crypt hyperplasia. A gene profiling analysis in diseased Hnf4alpha null colon confirms profound genetic changes in cell death and proliferative behaviour related to cancer. Among the genes involved in the immune protection through epithelial barrier function, we identify the ion transporter claudin-15 to be down-modulated early in the colon of Hnf4alpha mutants. This coincides with a significant decrease of mucosal ion transport but not of barrier permeability in young animals prior to the manifestation of the disease. We confirm that claudin-15 is a direct Hnf4alpha gene target in the intestinal epithelial context and is down-modulated in mouse experimental colitis and inflammatory bowel disease. CONCLUSION: Our results highlight the critical role of Hnf4alpha to maintain intestinal inflammatory homeostasis during mouse adult life and uncover a novel function for Hnf4alpha in the regulation of claudin-15 expression. This establishes Hnf4alpha as a mediator of ion epithelial transport, an important process for the maintenance of gut inflammatory homeostasis
Особенности учета заработной платы на примере УФПС "Почта России"
Исследование системы учета труда и заработной платы в ФГУП "Почта России".Research of the system of account of labour and salary in ФГУП "Mail of Russia"
letter to tHe eDitor
Bhat M, Lu Y, Marcil V, et al. Tumour necrosis factor-alpha polymorphism increases the risk for nonvariceal upper gastrointestinal bleeding in patients taking proton pump inhibitors. Can J Gastroenterol Hepatol 2014;28(9):488. To the Editor: Nonvariceal upper gastrointestinal bleeding (NVUGIB) is associated with significant morbidity, affecting 50 to 150 per 100,000 adults annually (1). Patients with NVUGIB may present with melena, hematochezia or coffee-ground emesis, often accompanied by a decrease in hemoglobin levels and even hemodynamic instability. Nonsteroidal anti-inflammatory drugs (NSAIDs) and Helicobacter pylori infection are the principal risk factors for NVUGIB, accounting for >95% of cases. Taking proton pump inhibitors (PPIs) is a known protective factor against NVUGIB. There has recently been growing interest in a possible genetic predisposition to NVUGIB, with investigation of single nucleotide polymorphisms (SNPs) associated with bleeding events. Of particular interest have been mutations in proinflammatory genes or genes that regulate NSAID/PPI metabolism, which may contribute to excessive inflammation and ulceration in the context of H pylori infection and NSAID use. A recent pharmacogenomic study The above literature describing a genetic predisposition for bleeding events applies principally to East Asian patient populations. Therefore, we decided to study whether such genetic associations could be elicited in the Canadian context. We performed a pilot study to assess the association of SNPs involved in NSAID metabolism (CYP2C9) and inflammatory response (TNF-α) with NVUGIB events. Patients who were part of the REASON-II NVUGIB study population at the McGill University Health Centre (Montreal, Quebec) were recruited (5). Study controls were asymptomatic patients undergoing screening colonoscopy, and excluded if there was any history of NVUGIB. DNA extracted from serum was genotyped for SNPs in the proinflammatory TNF-α (rs1799724, rs1800630, rs1799964) and NSAID-metabolizing CYP2C9 genes (rs1799853, rs1057910). Using STATA version 10, we assessed for any association between SNPs and NVUGIB events using logistic regression analysis and stratifying according to H pylori status, NSAID and PPI use. Our study included 23 patients and 46 controls of comparable age and sex, with NSAID (26.1% versus 6.7%) and PPI use (21.7% versus 13.0%) being more prevalent among patients. The TNFα1031C SNP, a proinflammatory cytokine polymorphism, was more common among patients with NVUGIB (OR 2.2 [95% CI 0.9 to 5.1]; P=0.084), particularly among those using PPIs (OR 20.0 [95% CI 0.9 to 429.9]; P=0.056) or not taking NSAIDs (OR 3.2 [95% CI 1.1 to 9.0]; P=0.027) at the time of the bleeding event. There was a trend in association of the TNF-α863A SNP with NVUGIB in patients not taking NSAIDs (OR 2.7 [95% CI 0.9 to 8.6]; P=0.071). We did not detect an association between CYP2C9 polymorphisms and NVUGIB, a result similar to that obtained in the study by Musumba et al (2). In conclusion, our pilot study demonstrates that TNF-α1031C SNP confers a risk for NVUGIB events among patients taking PPIs, a finding compatible with previous studies showing increased risk for peptic ulceration with this particular SNP (3
Diagnostic Delay Is Associated with Complicated Disease and Growth Impairment in Paediatric Crohn\u27s Disease
Background: Paediatric data on the association between diagnostic delay and inflammatory bowel disease [IBD] complications are lacking. We aimed to determine the effect of diagnostic delay on stricturing/fistulising complications, surgery, and growth impairment in a large paediatric cohort, and to identify predictors of diagnostic delay. Methods: We conducted a national, prospective, multicentre IBD inception cohort study including 1399 children. Diagnostic delay was defined as time from symptom onset to diagnosis \u3e75th percentile. Multivariable proportional hazards [PH] regression was used to examine the association between diagnostic delay and stricturing/fistulising complications and surgery, and multivariable linear regression to examine the association between diagnostic delay and growth. Predictors of diagnostic delay were identified using Cox PH regression. Results: Overall (64% Crohn\u27s disease [CD]; 36% ulcerative colitis/IBD unclassified [UC/IBD-U]; 57% male]), median time to diagnosis was 4.2 (interquartile range [IQR] 2.0-9.2) months. For the overall cohort, diagnostic delay was \u3e9.2 months; in CD, \u3e10.8 months and in UC/IBD-U, \u3e6.6 months. In CD, diagnostic delay was associated with a 2.5-fold higher rate of strictures/internal fistulae (hazard ratio [HR] 2.53, 95% confidence interval [CI] 1.41-4.56). Every additional month of diagnostic delay was associated with a decrease in height-for-age z-score of 0.013 standard deviations [95% CI 0.005-0.021]. Associations persisted after adjusting for disease location and therapy. No independent association was observed between diagnostic delay and surgery in CD or UC/IBD-U. Diagnostic delay was more common in CD, particularly small bowel CD. Abdominal pain, including isolated abdominal pain in CD, was associated with diagnostic delay. Conclusions: Diagnostic delay represents a risk factor for stricturing/internal fistulising complications and growth impairment in paediatric CD
Oxidative Stress and Mitochondrial Functions in the Intestinal Caco-2/15 Cell Line
Although mitochondrial dysfunction and oxidative stress are central mechanisms in various pathological conditions, they have not been extensively studied in the gastrointestinal tract, which is known to be constantly exposed to luminal oxidants from ingested foods. Key among these is the simultaneous consumption of iron salts and ascorbic acid, which can cause oxidative damage to biomolecules.The objective of the present work was to evaluate how iron-ascorbate (FE/ASC)-mediated lipid peroxidation affects mitochondrion functioning in Caco-2/15 cells. Our results show that treatment of Caco-2/15 cells with FE/ASC (0.2 mM/2 mM) (1) increased malondialdehyde levels assessed by HPLC; (2) reduced ATP production noted by luminescence assay; (3) provoked dysregulation of mitochondrial calcium homeostasis as evidenced by confocal fluorescence microscopy; (4) upregulated the protein expression of cytochrome C and apoptotic inducing factor, indicating exaggerated apoptosis; (5) affected mitochondrial respiratory chain complexes I, II, III and IV; (6) elicited mtDNA lesions as illustrated by the raised levels of 8-OHdG; (7) lowered DNA glycosylase, one of the first lines of defense against 8-OHdG mutagenicity; and (8) altered the gene expression and protein mass of mitochondrial transcription factors (mtTFA, mtTFB1, mtTFB2) without any effects on RNA Polymerase. The presence of the powerful antioxidant BHT (50 microM) prevented the occurrence of oxidative stress and most of the mitochondrial abnormalities.Collectively, our findings indicate that acute exposure of Caco-2/15 cells to FE/ASC-catalyzed peroxidation produces harmful effects on mitochondrial functions and DNA integrity, which are abrogated by the powerful exogenous BHT antioxidant. Functional derangements of mitochondria may have implications in oxidative stress-related disorders such as inflammatory bowel diseases
Clinicians’ Guide to the Use of Fecal Calprotectin to Identify and Monitor Disease Activity in Inflammatory Bowel Disease
BACKGROUND: Objective monitoring of the severity of inflammation in patients with inflammatory bowel disease (IBD) is an essential part of disease management. However, repeat endoscopy to define extent and severity of inflammation is not practical. Fecal calprotectin (FC) is a biomarker that can be used as a surrogate test to distinguish inflammatory from noninflammatory gastrointestinal disease
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