Showing papers in "Gut in 2015"

Kyoto global consensus report on Helicobacter pylori gastritis

Abstract: Objective To present results of the Kyoto Global Consensus Meeting, which was convened to develop global consensus on (1) classification of chronic gastritis and duodenitis, (2) clinical distinction of dyspepsia caused by Helicobacter pylori from functional dyspepsia, (3) appropriate diagnostic assessment of gastritis and (4) when, whom and how to treat H. pylori gastritis. Design Twenty-three clinical questions addressing the above-mentioned four domains were drafted for which expert panels were asked to formulate relevant statements. A Delphi method using an anonymous electronic system was adopted to develop the consensus, the level of which was predefined as ≥80%. Final modifications of clinical questions and consensus were achieved at the face-to-face meeting in Kyoto. Results All 24 statements for 22 clinical questions after extensive modifications and omission of one clinical question were achieved with a consensus level of >80%. To better organise classification of gastritis and duodenitis based on aetiology, a new classification of gastritis and duodenitis is recommended for the 11th international classification. A new category of H. pylori -associated dyspepsia together with a diagnostic algorithm was proposed. The adoption of grading systems for gastric cancer risk stratification, and modern image-enhancing endoscopy for the diagnosis of gastritis, were recommended. Treatment to eradicate H. pylori infection before preneoplastic changes develop, if feasible, was recommended to minimise the risk of more serious complications of the infection. Conclusions A global consensus for gastritis was developed for the first time, which will be the basis for an international classification system and for further research on the subject.

Global incidence of oesophageal cancer by histological subtype in 2012

Abstract: Objective The two major histological types of oesophageal cancer—adenocarcinoma (AC) and squamous cell carcinoma (SCC)—are known to differ greatly in terms of risk factors and epidemiology. To date, global incidence estimates for individual subtypes are still lacking. This study for the first time quantified the global burden of oesophageal cancer by histological subtype. Design Where available, data from Cancer Incidence in Five Continents Vol. X (CI5X) were used to compute, age-specific, sex-specific and country-specific proportions of AC and SCC. Nine regional averages were computed for countries without CI5X data. The proportions were then applied to all oesophageal cancer cases from GLOBOCAN 2012 and age-standardised incidence rates calculated for both histological types. Results Worldwide, an estimated 398 000 SCCs and 52 000 ACs of the oesophagus occurred in 2012, translating to incidence rates of 5.2 and 0.7 per 100 000, respectively. Although SCCs were most common in South-Eastern and Central Asia (79% of the total global SCC cases), the highest burden of AC was found in Northern and Western Europe, Northern America and Oceania (46% of the total global AC cases). Men had substantially higher incidence than women, especially in the case of AC (male to female ratio AC: 4.4; SCC: 2.7). Conclusions These first global estimates of oesophageal cancer incidence by histology suggested a high concentration of AC in high-income countries with men being at much greater risk. This quantification of incidence will aid health policy makers to plan appropriate cancer control measures in the future.

Effects of targeted delivery of propionate to the human colon on appetite regulation, body weight maintenance and adiposity in overweight adults

Abstract: Objective The colonic microbiota ferment dietary fibres, producing short chain fatty acids. Recent evidence suggests that the short chain fatty acid propionate may play an important role in appetite regulation. We hypothesised that colonic delivery of propionate would increase peptide YY (PYY) and glucagon like peptide-1 (GLP-1) secretion in humans, and reduce energy intake and weight gain in overweight adults. Design To investigate whether propionate promotes PYY and GLP-1 secretion, a primary cultured human colonic cell model was developed. To deliver propionate specifically to the colon, we developed a novel inulin-propionate ester. An acute randomised, controlled cross-over study was used to assess the effects of this inulin-propionate ester on energy intake and plasma PYY and GLP-1 concentrations. The long-term effects of inulin-propionate ester on weight gain were subsequently assessed in a randomised, controlled 24-week study involving 60 overweight adults. Results Propionate significantly stimulated the release of PYY and GLP-1 from human colonic cells. Acute ingestion of 10 g inulin-propionate ester significantly increased postprandial plasma PYY and GLP-1 and reduced energy intake. Over 24 weeks, 10 g/day inulin-propionate ester supplementation significantly reduced weight gain, intra-abdominal adipose tissue distribution, intrahepatocellular lipid content and prevented the deterioration in insulin sensitivity observed in the inulin-control group. Conclusions These data demonstrate for the first time that increasing colonic propionate prevents weight gain in overweight adult humans. Trial registration number NCT00750438.

Colorectal cancer screening: a global overview of existing programmes

Abstract: Colorectal cancer (CRC) ranks third among the most commonly diagnosed cancers worldwide, with wide geographical variation in incidence and mortality across the world. Despite proof that screening can decrease CRC incidence and mortality, CRC screening is only offered to a small proportion of the target population worldwide. Throughout the world there are widespread differences in CRC screening implementation status and strategy. Differences can be attributed to geographical variation in CRC incidence, economic resources, healthcare structure and infrastructure to support screening such as the ability to identify the target population at risk and cancer registry availability. This review highlights issues to consider when implementing a CRC screening programme and gives a worldwide overview of CRC burden and the current status of screening programmes, with focus on international differences.

A polyphenol-rich cranberry extract protects from diet-induced obesity, insulin resistance and intestinal inflammation in association with increased Akkermansia spp. population in the gut microbiota of mice

Abstract: Objective The increasing prevalence of obesity and type 2 diabetes (T2D) demonstrates the failure of conventional treatments to curb these diseases. The gut microbiota has been put forward as a key player in the pathophysiology of diet-induced T2D. Importantly, cranberry ( Vaccinium macrocarpon Aiton) is associated with a number of beneficial health effects. We aimed to investigate the metabolic impact of a cranberry extract (CE) on high fat/high sucrose (HFHS)-fed mice and to determine whether its consequent antidiabetic effects are related to modulations in the gut microbiota. Design C57BL/6J mice were fed either a chow or a HFHS diet. HFHS-fed mice were gavaged daily either with vehicle (water) or CE (200 mg/kg) for 8 weeks. The composition of the gut microbiota was assessed by analysing 16S rRNA gene sequences with 454 pyrosequencing. Results CE treatment was found to reduce HFHS-induced weight gain and visceral obesity. CE treatment also decreased liver weight and triglyceride accumulation in association with blunted hepatic oxidative stress and inflammation. CE administration improved insulin sensitivity, as revealed by improved insulin tolerance, lower homeostasis model assessment of insulin resistance and decreased glucose-induced hyperinsulinaemia during an oral glucose tolerance test. CE treatment was found to lower intestinal triglyceride content and to alleviate intestinal inflammation and oxidative stress. Interestingly, CE treatment markedly increased the proportion of the mucin-degrading bacterium Akkermansia in our metagenomic samples. Conclusions CE exerts beneficial metabolic effects through improving HFHS diet-induced features of the metabolic syndrome, which is associated with a proportional increase in Akkermansia spp. population.

Pathobiology of liver fibrosis: a translational success story

Abstract: Reversibility of hepatic fibrosis and cirrhosis following antiviral therapy for hepatitis B or C has advanced the prospect of developing antifibrotic therapies for patients with chronic liver diseases, especially non-alcoholic steatohepatitis. Mechanisms of fibrosis have focused on hepatic stellate cells, which become fibrogenic myofibroblasts during injury through ‘activation’, and are at the nexus of efforts to define novel drug targets. Recent studies have clarified pathways of stellate cell gene regulation and epigenetics, emerging pathways of fibrosis regression through the recruitment and amplification of fibrolytic macrophages, nuanced responses of discrete inflammatory cell subsets and the identification of the ‘ductular reaction’ as a marker of severe injury and repair. Based on our expanded knowledge of fibrosis pathogenesis, attention is now directed towards strategies for antifibrotic therapies and regulatory challenges for conducting clinical trials with these agents. New therapies are attempting to: 1) Control or cure the primary disease or reduce tissue injury; 2) Target receptor-ligand interactions and intracellular signaling; 3) Inhibit fibrogenesis; and 4) Promote resolution of fibrosis. Progress is urgently needed in validating non-invasive markers of fibrosis progression and regression that can supplant biopsy and shorten the duration of clinical trials. Both scientific and clinical challenges remain, however the past three decades of steady progress in understanding liver fibrosis have contributed to an emerging translational success story, with realistic hopes for antifibrotic therapies to treat patients with chronic liver disease in the near future.

HBV cccDNA: viral persistence reservoir and key obstacle for a cure of chronic hepatitis B

Abstract: At least 250 million people worldwide are chronically infected with HBV, a small hepatotropic DNA virus that replicates through reverse transcription. Chronic infection greatly increases the risk for terminal liver disease. Current therapies rarely achieve a cure due to the refractory nature of an intracellular viral replication intermediate termed covalently closed circular (ccc) DNA. Upon infection, cccDNA is generated as a plasmid-like episome in the host cell nucleus from the protein-linked relaxed circular (RC) DNA genome in incoming virions. Its fundamental role is that as template for all viral RNAs, and in consequence new virions. Biosynthesis of RC-DNA by reverse transcription of the viral pregenomic RNA is now understood in considerable detail, yet conversion of RC-DNA to cccDNA is still obscure, foremostly due to the lack of feasible, cccDNA-dependent assay systems. Conceptual and recent experimental data link cccDNA formation to cellular DNA repair, which is increasingly appreciated as a critical interface between cells and viruses. Together with new in vitro HBV infection systems, based on the identification of the bile acid transporter sodium taurocholate cotransporting polypeptide as an HBV entry receptor, this offers novel opportunities to decipher, and eventually interfere with, formation of the HBV persistence reservoir. After a brief overview of the role of cccDNA in the HBV infectious cycle, this review aims to summarise current knowledge on cccDNA molecular biology, to highlight the experimental restrictions that have hitherto hampered faster progress and to discuss cccDNA as target for new, potentially curative therapies of chronic hepatitis B.

Diets that differ in their FODMAP content alter the colonic luminal microenvironment

Abstract: Objective A low FODMAP (Fermentable Oligosaccharides, Disaccharides, Monosaccharides And Polyols) diet reduces symptoms of IBS, but reduction of potential prebiotic and fermentative effects might adversely affect the colonic microenvironment. The effects of a low FODMAP diet with a typical Australian diet on biomarkers of colonic health were compared in a single-blinded, randomised, cross-over trial. Design Twenty-seven IBS and six healthy subjects were randomly allocated one of two 21-day provided diets, differing only in FODMAP content (mean (95% CI) low 3.05 (1.86 to 4.25) g/day vs Australian 23.7 (16.9 to 30.6) g/day), and then crossed over to the other diet with ≥21-day washout period. Faeces passed over a 5-day run-in on their habitual diet and from day 17 to day 21 of the interventional diets were pooled, and pH, short-chain fatty acid concentrations and bacterial abundance and diversity were assessed. Results Faecal indices were similar in IBS and healthy subjects during habitual diets. The low FODMAP diet was associated with higher faecal pH (7.37 (7.23 to 7.51) vs 7.16 (7.02 to 7.30); p=0.001), similar short-chain fatty acid concentrations, greater microbial diversity and reduced total bacterial abundance (9.63 (9.53 to 9.73) vs 9.83 (9.72 to 9.93) log 10 copies/g; p Clostridium cluster XIVa (median ratio 6.62; p Akkermansia muciniphila (19.3; p Ruminococcus torques . Conclusions Diets differing in FODMAP content have marked effects on gut microbiota composition. The implications of long-term reduction of intake of FODMAPs require elucidation. Trial registration number ACTRN12612001185853.

Iron fortification adversely affects the gut microbiome, increases pathogen abundance and induces intestinal inflammation in Kenyan infants

Abstract: Background In-home iron fortification for infants in developing countries is recommended for control of anaemia, but low absorption typically results in >80% of the iron passing into the colon. Iron is essential for growth and virulence of many pathogenic enterobacteria. We determined the effect of high and low dose in-home iron fortification on the infant gut microbiome and intestinal inflammation. Methods We performed two double-blind randomised controlled trials in 6-month-old Kenyan infants (n=115) consuming home-fortified maize porridge daily for 4 months. In the first, infants received a micronutrient powder (MNP) containing 2.5 mg iron as NaFeEDTA or the MNP without iron. In the second, they received a different MNP containing 12.5 mg iron as ferrous fumarate or the MNP without the iron. The primary outcome was gut microbiome composition analysed by 16S pyrosequencing and targeted real-time PCR (qPCR). Secondary outcomes included faecal calprotectin (marker of intestinal inflammation) and incidence of diarrhoea. We analysed the trials separately and combined. Results At baseline, 63% of the total microbial 16S rRNA could be assigned to Bifidobacteriaceae but there were high prevalences of pathogens, including Salmonella Clostridium difficile , Clostridium perfringens , and pathogenic Escherichia coli . Using pyrosequencing, +FeMNPs increased enterobacteria, particularly Escherichia / Shigella (p=0.048), the enterobacteria/bifidobacteria ratio (p=0.020), and Clostridium (p=0.030). Most of these effects were confirmed using qPCR; for example, +FeMNPs increased pathogenic E. coli strains (p=0.029). +FeMNPs also increased faecal calprotectin (p=0.002). During the trial, 27.3% of infants in +12.5 mgFeMNP required treatment for diarrhoea versus 8.3% in −12.5 mgFeMNP (p=0.092). There were no study-related serious adverse events in either group. Conclusions In this setting, provision of iron-containing MNPs to weaning infants adversely affects the gut microbiome, increasing pathogen abundance and causing intestinal inflammation. Trial registration number NCT01111864.

Circulating microRNA signature in non-alcoholic fatty liver disease: from serum non-coding RNAs to liver histology and disease pathogenesis

Abstract: Objectives We used a screening strategy of global serum microRNA (miRNA) profiling, followed by a second stage of independent replication and exploration of liver expression of selected miRNAs to study: (1) the circulating miRNA signature associated with non-alcoholic fatty liver disease (NAFLD) progression and predictive power, (2) the role of miRNAs in disease biology and (3) the association between circulating miRNAs and features of the metabolic syndrome. Methods The study used a case-control design and included patients with NAFLD proven through biopsy and healthy controls. Results Among 84 circulating miRNAs analysed, miR-122, miR-192, miR-19a and miR-19b, miR-125b, and miR-375 were upregulated >2-fold (p Conclusions miR-122 plays a role of physiological significance in the biology of NAFLD; circulating miRNAs mirror the histological and molecular events occurring in the liver. NAFLD has a distinguishing circulating miRNA profile associated with a global dysmetabolic disease state and cardiovascular risk.

Stromal biology and therapy in pancreatic cancer: a changing paradigm

Abstract: Pancreatic ductal adenocarcinoma (PDA) exhibits one of the poorest prognosis of all solid tumours and poses an unsolved problem in cancer medicine. Despite the recent success of two combination chemotherapies for palliative patients, the modest survival benefits are often traded against significant side effects and a compromised quality of life. Although the molecular events underlying the initiation and progression of PDA have been intensively studied and are increasingly understood, the reasons for the poor therapeutic response are hardly apprehended. One leading hypothesis over the last few years has been that the pronounced tumour microenvironment in PDA not only promotes carcinogenesis and tumour progression but also mediates therapeutic resistance. To this end, targeting of various stromal components and pathways was considered a promising strategy to biochemically and biophysically enhance therapeutic response. However, none of the efforts have yet led to efficacious and approved therapies in patients. Additionally, recent data have shown that tumour-associated fibroblasts may restrain rather than promote tumour growth, reinforcing the need to critically revisit the complexity and complicity of the tumour-stroma with translational implications for future therapy and clinical trial design.

Long-term adenoma recurrence following wide-field endoscopic mucosal resection (WF-EMR) for advanced colonic mucosal neoplasia is infrequent: results and risk factors in 1000 cases from the Australian Colonic EMR (ACE) study

Abstract: Objective Wide-field endoscopic mucosal resection (WF-EMR) is an alternative to surgery for treatment of advanced colonic mucosal neoplasia up to 120 mm in size, but has been criticised for its potentially high recurrence rates. We aimed to quantify recurrence at 4 months (early) and 16 months (late) following successful WF-EMR and identify its risk factors and clinical significance. Design Ongoing multicentre, prospective, intention-to-treat analysis of sessile or laterally spreading colonic lesions ≥20 mm in size referred for WF-EMR to seven academic endoscopy units. Surveillance colonoscopy (SC) was performed 4 months (SC1) and 16 months (SC2) after WF-EMR, with photographic documentation and biopsy of the scar. Results 1134 consecutive patients were enrolled when 1000 successful EMRs were achieved, of whom 799 have undergone SC1. 670 were normal. Early recurrent/residual adenoma was present in 128 (16.0%, 95% CI 13.6% to 18.7%). One case was unknown. The recurrent/residual adenoma was diminutive in 71.7% of cases. On multivariable analysis, risk factors were lesion size >40 mm, use of argon plasma coagulation and intraprocedural bleeding. Of 670 with normal SC1, 426 have undergone SC2, with late recurrence present in 17 cases (4.0%, 95% CI 2.4% to 6.2%). Overall, recurrent/residual adenoma was successfully treated endoscopically in 135 of 145 cases (93.1%, 95% CI 88.1% to 96.4%). If the initial EMR was deemed successful and did not contain submucosal invasion requiring surgery, 98.1% (95% CI 96.6% to 99.0%) were adenoma-free and had avoided surgery at 16 months following EMR. Conclusions Following colonic WF-EMR, early recurrent/residual adenoma occurs in 16%, and is usually unifocal and diminutive. Risk factors were identified. Late recurrence occurs in 4%. Overall, recurrence was managed endoscopically in 93% of cases. Recurrence is not a significant clinical problem following WF-EMR, as with strict colonoscopic surveillance, it can be managed endoscopically with high success rates. Trial registration number: NCT01368289.

Development of an enhanced human gastrointestinal epithelial culture system to facilitate patient-based assays

Abstract: Objective The technology for the growth of human intestinal epithelial cells is rapidly progressing. An exciting possibility is that this system could serve as a platform for individualised medicine and research. However, to achieve this goal, human epithelial culture must be enhanced so that biopsies from individuals can be used to reproducibly generate cell lines in a short time frame so that multiple, functional assays can be performed (ie, barrier function and host–microbial interactions). Design We created a large panel of human gastrointestinal epithelial cell lines (n=65) from patient biopsies taken during routine upper and lower endoscopy procedures. Proliferative stem/progenitor cells were rapidly expanded using a high concentration of conditioned media containing the factors critical for growth (Wnt3a, R-spondin and Noggin). A combination of lower conditioned media concentration and Notch inhibition was used to differentiate these cells for additional assays. Results We obtained epithelial lines from all accessible tissue sites within 2 weeks of culture. The intestinal cell lines were enriched for stem cell markers and rapidly grew as spheroids that required passage at 1:3–1:4 every 3 days. Under differentiation conditions, intestinal epithelial spheroids showed region-specific development of mature epithelial lineages. These cells formed functional, polarised monolayers covered by a secreted mucus layer when grown on Transwell membranes. Using two-dimensional culture, these cells also demonstrated novel adherence phenotypes with various strains of pathogenic Escherichia coli . Conclusions This culture system will facilitate the study of interindividual, functional studies of human intestinal epithelial cells, including host–microbial interactions.

Diagnosis and management of acute kidney injury in patients with cirrhosis: Revised consensus recommendations of the International Club of Ascites

Abstract: Acute renal failure (ARF) is a common complication in patients with decompensated cirrhosis The traditional diagnostic criteria of renal failure in these patients were proposed in 19961 and have been refined in subsequent years2 According to these criteria, ARF is defined as an increase in serum creatinine (sCr) of ≥50% from baseline to a final value >15 mg/dL (133 µmol/L) However, the threshold value of 15 mg/dL (133 µmol/L) sCr to define renal failure in patients with decompensated cirrhosis has been challenged3 ,4 In addition, the timeframe to distinguish acute from chronic renal failure has not been clearly identified, the only exception being type 1 hepatorenal syndrome (HRS) Meanwhile, new definitions for ARF, now termed acute kidney injury (AKI), have been proposed and validated in patients without cirrhosis5–7 Recently these new criteria were also proposed and applied in the diagnosis of AKI in patients with cirrhosis3 ,8–15 Thus, in December 2012, the International Club of Ascites (ICA) organised a consensus development meeting in Venice, Italy, in order to reach a new definition of AKI in patients with cirrhosis The discussion among the experts continued thereafter for 2 years, both online and through several meetings, between those experts who had different positions on crucial points on the subject This paper reports the scientific evidence supporting the final proposal of a new approach to the diagnosis and treatment of this condition, on which the experts agreed AKI is defined as an acute significant reduction in the glomerular filtration rate (GFR) sCr remains the most practical biomarker of renal function in patients with ARF (with or without cirrhosis) However, sCr as a biomarker of renal function has many limitations in clinical practice since it is influenced by bodyweight, race, age, and gender The use of sCr in patients with cirrhosis is …

Global prevalence of, and risk factors for, uninvestigated dyspepsia: a meta-analysis

Abstract: Objectives Many cross-sectional surveys have reported the prevalence of uninvestigated dyspepsia, but there has been no recent systematic review of data from all studies to determine its global prevalence and risk factors. Design MEDLINE, EMBASE and EMBASE Classic were searched (until January 2014) to identify population-based studies that reported the prevalence of uninvestigated dyspepsia in adults (≥15 years old); dyspepsia was defined using symptom-based criteria or questionnaires. The prevalence of dyspepsia was extracted for all studies and according to the criteria used to define it. Pooled prevalence, according to study location and certain other characteristics, ORs and 95% CIs were calculated. Results Of the 306 citations evaluated, 103 reported the prevalence of uninvestigated dyspepsia in 100 separate study populations, containing 312 415 subjects. Overall pooled prevalence in all studies was 20.8% (95% CI 17.8% to 23.9%). The prevalence varied according to country (from 1.8% to 57.0%) and criteria used to define dyspepsia. The greatest prevalence values were found when a broad definition of dyspepsia (29.5%; 95% CI 25.3% to 33.8%) or upper abdominal or epigastric pain or discomfort (20.4%; 95% CI 16.3% to 24.8%) were used. The prevalence was higher in women (OR 1.24; 95% CI 1.13 to 1.36), smokers (OR 1.25; 95% CI 1.12 to 1.40), non-steroidal anti-inflammatory drug (NSAID) users (OR 1.59; 95% CI 1.27 to 1.99) and Helicobacter pylori -positive individuals (OR 1.18; 95% CI 1.04 to 1.33). Conclusions The overall pooled prevalence of uninvestigated dyspepsia was 21%, but varied among countries and according to the criteria used to define its presence. Prevalence is significantly higher in women, smokers, NSAID users and H. pylori -positive individuals, although these associations were modest.

An updated Asia Pacific Consensus Recommendations on colorectal cancer screening

Abstract: Objective Since the publication of the first Asia Pacific Consensus on Colorectal Cancer (CRC) in 2008, there are substantial advancements in the science and experience of implementing CRC screening. The Asia Pacific Working Group aimed to provide an updated set of consensus recommendations. Design Members from 14 Asian regions gathered to seek consensus using other national and international guidelines, and recent relevant literature published from 2008 to 2013. A modified Delphi process was adopted to develop the statements. Results Age range for CRC screening is defined as 50–75 years. Advancing age, male, family history of CRC, smoking and obesity are confirmed risk factors for CRC and advanced neoplasia. A risk-stratified scoring system is recommended for selecting high-risk patients for colonoscopy. Quantitative faecal immunochemical test (FIT) instead of guaiac-based faecal occult blood test (gFOBT) is preferred for average-risk subjects. Ancillary methods in colonoscopy, with the exception of chromoendoscopy, have not proven to be superior to high-definition white light endoscopy in identifying adenoma. Quality of colonoscopy should be upheld and quality assurance programme should be in place to audit every aspects of CRC screening. Serrated adenoma is recognised as a risk for interval cancer. There is no consensus on the recruitment of trained endoscopy nurses for CRC screening. Conclusions Based on recent data on CRC screening, an updated list of recommendations on CRC screening is prepared. These consensus statements will further enhance the implementation of CRC screening in the Asia Pacific region.

Global patterns of cardia and non-cardia gastric cancer incidence in 2012

Abstract: Objective Globally, gastric cancer incidence shows remarkable international variation and demonstrates distinct characteristics by the two major topographical subsites, cardia (CGC) and non-cardia (NCGC). Because global incidence estimates by subsite are lacking, we aimed to describe the worldwide incidence patterns of CGC and NCGC separately. Design Using Cancer Incidence in Five Continents Volume X (CI5X), we ascertained the proportions of CGC and NCGC by country, sex and age group ( Results According to our estimates, in 2012, there were 260 000 cases of CGC (ASR 3.3 per 100 000) and 691 000 cases of NCGC (ASR 8.8) worldwide. The highest regional rates of both gastric cancer subsites were in Eastern/Southeastern Asia (in men, ASRs: 8.7 and 21.7 for CGC and NCGC, respectively). In most countries NCGC occurred more frequently than CGC with an average ratio of 2:1; however, in some populations where NCGC incidence rates were lower than the global average, CGC rates were similar or higher than NCGC rates. Men had higher rates than women for both subsites but particularly for CGC (male-to-female ratio 3:1). Conclusions This study has, for the first time, quantified global incidence patterns of CGC and NCGC providing new insights into the global burden of these cancers. Country-specific estimates are provided; however, these should be interpreted with caution. This work will support future investigations across populations.

Environmental risk factors in inflammatory bowel disease: a population-based case-control study in Asia-Pacific

Abstract: Objective The rising incidence of inflammatory bowel disease in Asia supports the importance of environmental risk factors in disease aetiology. This prospective population-based case-control study in Asia-Pacific examined risk factors prior to patients developing IBD. Design 442 incident cases (186 Crohn9s disease (CD); 256 UC; 374 Asians) diagnosed between 2011 and 2013 from eight countries in Asia and Australia and 940 controls (frequency-matched by sex, age and geographical location; 789 Asians) completed an environmental factor questionnaire at diagnosis. Unconditional logistic regression models were used to estimate adjusted ORs (aOR) and 95% CIs. Results In multivariate model, being breast fed >12 months (aOR 0.10; 95% CI 0.04 to 0.30), antibiotic use (aOR 0.19; 0.07 to 0.52), having dogs (aOR 0.54; 0.35 to 0.83), daily tea consumption (aOR 0.62; 0.43 to 0.91) and daily physical activity (aOR 0.58; 0.35 to 0.96) decreased the odds for CD in Asians. In UC, being breast fed >12 months (aOR 0.16; 0.08 to 0.31), antibiotic use (aOR 0.48; 0.27 to 0.87), daily tea (aOR 0.63; 0.46 to 0.86) or coffee consumption (aOR 0.51; 0.36 to 0.72), presence of hot water tap (aOR 0.65; 0.46 to 0.91) and flush toilet in childhood (aOR 0.71; 0.51 to 0.98) were protective for UC development whereas ex-smoking (aOR 2.02; 1.22 to 3.35) increased the risk of UC. Conclusions This first population-based study of IBD risk factors in Asia-Pacific supports the importance of childhood immunological, hygiene and dietary factors in the development of IBD, suggesting that markers of altered intestinal microbiota may modulate risk of IBD later in life.

Intestinal epithelial vitamin D receptor deletion leads to defective autophagy in colitis

Abstract: Objective Vitamin D and the vitamin D receptor (VDR) appear to be important immunological regulators of inflammatory bowel diseases (IBD). Defective autophagy has also been implicated in IBD, where interestingly, polymorphisms of genes such as ATG16L1 have been associated with increased risk. Although vitamin D, the microbiome and autophagy are all involved in pathogenesis of IBD, it remains unclear whether these processes are related or function independently. Design We investigated the effects and mechanisms of intestinal epithelial VDR in healthy and inflamed states using cell culture models, a conditional VDR knockout mouse model (VDR ΔIEC ), colitis models and human samples. Results Absence of intestinal epithelial VDR affects microbial assemblage and increases susceptibility to dextran sulfate sodium-induced colitis. Intestinal epithelial VDR downregulates expressions of ATG16L1 and lysozyme, and impairs antimicrobial function of Paneth cells. Gain and loss-of-function assays showed that VDR levels regulate ATG16L1 and lysozyme at the transcriptional and translational levels. Moreover, low levels of intestinal epithelial VDR correlated with reduced ATG16L1 and representation by intestinal Bacteroides in patients with IBD. Administration of the butyrate (a fermentation product of gut microbes) increases intestinal VDR expression and suppresses inflammation in a colitis model. Conclusions Our study demonstrates fundamental relationship between VDR, autophagy and gut microbial assemblage that is essential for maintaining intestinal homeostasis, but also in contributing to the pathophysiology of IBD. These insights can be leveraged to define therapeutic targets for restoring VDR expression and function.

The HLA-DQ2 genotype selects for early intestinal microbiota composition in infants at high risk of developing coeliac disease

Abstract: Objective Intestinal dysbiosis has been associated with coeliac disease (CD), but whether the alterations are cause or consequence of the disease is unknown. This study investigated whether the human leukocyte antigen (HLA)-DQ2 genotype is an independent factor influencing the early gut microbiota composition of healthy infants at family risk of CD. Design As part of a larger prospective study, a subset (n=22) of exclusively breastfed and vaginally delivered infants with either high genetic risk (HLA-DQ2 carriers) or low genetic risk (non-HLA-DQ2/8 carriers) of developing CD were selected from a cohort of healthy infants with at least one first-degree relative with CD. Infant faecal microbiota was analysed by 16S rRNA gene pyrosequencing and real time quantitative PCR. Results Infants with a high genetic risk had significantly higher proportions of Firmicutes and Proteobacteria and lower proportions of Actinobacteria compared with low-risk infants. At genus level, high-risk infants had significantly less Bifidobacterium and unclassified Bifidobacteriaceae proportions and more Corynebacterium, Gemella, Clostridium sensu stricto, unclassified Clostridiaceae, unclassified Enterobacteriaceae and Raoultella proportions. Quantitative real time PCR also revealed lower numbers of Bifidobacterium species in infants with high genetic risk than in those with low genetic risk. In high-risk infants negative correlations were identified between Bifidobacterium species and several genera of Proteobacteria (Escherichia/Shigella) and Firmicutes (Clostridium). Conclusions The genotype of infants at family risk of developing CD, carrying the HLA-DQ2 haplotypes, influences the early gut microbiota composition. This finding suggests that a specific disease-biased host genotype may also select for the first gut colonisers and could contribute to determining disease risk.

The relationship between infliximab concentrations, antibodies to infliximab and disease activity in Crohn's disease

Abstract: Objective Although low infliximab trough concentrations and antibodies to infliximab (ATI) are associated with poor outcomes in patients with Crohn9s disease (CD), the clinical relevance of ATI in patients with adequate infliximab concentrations is uncertain. We evaluated this question using an assay sensitive for identification of ATI in the presence of infliximab. Design In an observational study, 1487 trough serum samples from 483 patients with CD who participated in four clinical studies of maintenance infliximab therapy were analysed using a fluid phase mobility shift assay. Infliximab and ATI concentrations most discriminant for remission, defined as a C-reactive protein concentration of ≤5 mg/L, were determined by receiver operating characteristic curves. A multivariable regression model evaluated these factors as independent predictors of remission. Results Based upon analysis of 1487 samples, 77.1% of patients had detectable and 22.9% had undetectable infliximab concentrations, of which 9.5% and 71.8%, respectively, were positive for ATI. An infliximab concentration of >2.79 μg/mL (area under the curve (AUC)=0.681; 95% CI 0.632 to 0.731) and ATI concentration of Conclusions The development of ATI increases the probability of active disease even at low concentrations and in the presence of a therapeutic concentration of drug during infliximab maintenance therapy. Evaluation of strategies to prevent ATI formation, including therapeutic drug monitoring with selective infliximab dose intensification, is needed.

Barrett's oesophagus patients with low-grade dysplasia can be accurately risk-stratified after histological review by an expert pathology panel

Abstract: Objective Reported malignant progression rates for low-grade dysplasia (LGD) in Barrett9s oesophagus (BO) vary widely. Expert histological review of LGD is advised, but limited data are available on its clinical value. This retrospective cohort study aimed to determine the value of an expert pathology panel organised in the Dutch Barrett9s Advisory Committee (BAC) by investigating the incidence rates of high-grade dysplasia (HGD) and oesophageal adenocarcinoma (OAC) after expert histological review of LGD. Design We included all BO cases referred to the BAC for histological review of LGD diagnosed between 2000 and 2011. The diagnosis of the expert panel was related to the histological outcome during endoscopic follow-up. Primary endpoint was development of HGD or OAC. Results 293 LGD patients (76% men; mean 63 years±11.9) were included. Following histological review, 73% was downstaged to non-dysplastic BO (NDBO) or indefinite for dysplasia (IND). In 27% the initial LGD diagnosis was confirmed. Endoscopic follow-up was performed in 264 patients (90%) with a median follow-up of 39 months (IQR 16–72). For confirmed LGD, the risk of HGD/OAC was 9.1% per patient-year. Patients downstaged to NDBO or IND had a malignant progression risk of 0.6% and 0.9% per patient-year, respectively. Conclusions Confirmed LGD in BO has a markedly increased risk of malignant progression. However, the vast majority of patients with community LGD will be downstaged after expert review and have a low progression risk. Therefore, all BO patients with LGD should undergo expert histological review of the diagnosis for adequate risk stratification.

Towards an HBV cure: state-of-the-art and unresolved questions—report of the ANRS workshop on HBV cure

Abstract: HBV infection is a major cause of liver cirrhosis and hepatocellular carcinoma. Although HBV infection can be efficiently prevented by vaccination, and treatments are available, to date there is no reliable cure for the >240 million individuals that are chronically infected worldwide. Current treatments can only achieve viral suppression, and lifelong therapy is needed in the majority of infected persons. In the framework of the French National Agency for Research on AIDS and Viral Hepatitis 'HBV Cure' programme, a scientific workshop was held in Paris in June 2014 to define the state-of-the-art and unanswered questions regarding HBV pathobiology, and to develop a concerted strategy towards an HBV cure. This review summarises our current understanding of HBV host-interactions leading to viral persistence, as well as the roadblocks to be overcome to ultimately address unmet medical needs in the treatment of chronic HBV infection.

The stomach in health and disease

Abstract: The stomach is traditionally regarded as a hollow muscular sac that initiates the second phase of digestion. Yet this simple view ignores the fact that it is the most sophisticated endocrine organ with unique physiology, biochemistry, immunology and microbiology. All ingested materials, including our nutrition, have to negotiate this organ first, and as such, the stomach is arguably the most important segment within the GI tract. The unique biological function of gastric acid secretion not only initiates the digestive process but also acts as a first line of defence against food-borne microbes. Normal gastric physiology and morphology may be disrupted by Helicobacter pylori infection, the most common chronic bacterial infection in the world and the aetiological agent for most peptic ulcers and gastric cancer. In this state-of-the-art review, the most relevant new aspects of the stomach in health and disease are addressed. Topics include gastric physiology and the role of gastric dysmotility in dyspepsia and gastroparesis; the stomach in appetite control and obesity; there is an update on the immunology of the stomach and the emerging field of the gastric microbiome. H. pylori-induced gastritis and its associated diseases including peptic ulcers and gastric cancer are addressed together with advances in diagnosis. The conclusions provide a future approach to gastric diseases underpinned by the concept that a healthy stomach is the gateway to a healthy and balanced host. This philosophy should reinforce any public health efforts designed to eradicate major gastric diseases, including stomach cancer.

Uncovering effects of antibiotics on the host and microbiota using transkingdom gene networks

Abstract: Objective Despite widespread use of antibiotics for the treatment of life-threatening infections and for research on the role of commensal microbiota, our understanding of their effects on the host is still very limited. Design Using a popular mouse model of microbiota depletion by a cocktail of antibiotics, we analysed the effects of antibiotics by combining intestinal transcriptome together with metagenomic analysis of the gut microbiota. In order to identify specific microbes and microbial genes that influence the host phenotype in antibiotic-treated mice, we developed and applied analysis of the transkingdom network. Results We found that most antibiotic-induced alterations in the gut can be explained by three factors: depletion of the microbiota; direct effects of antibiotics on host tissues and the effects of remaining antibiotic-resistant microbes. Normal microbiota depletion mostly led to downregulation of different aspects of immunity. The two other factors (antibiotic direct effects on host tissues and antibiotic-resistant microbes) primarily inhibited mitochondrial gene expression and amounts of active mitochondria, increasing epithelial cell death. By reconstructing and analysing the transkingdom network, we discovered that these toxic effects were mediated by virulence/quorum sensing in antibiotic-resistant bacteria, a finding further validated using in vitro experiments. Conclusions In addition to revealing mechanisms of antibiotic-induced alterations, this study also describes a new bioinformatics approach that predicts microbial components that regulate host functions and establishes a comprehensive resource on what, why and how antibiotics affect the gut in a widely used mouse model of microbiota depletion by antibiotics.

Impact on colorectal cancer mortality of screening programmes based on the faecal immunochemical test

Abstract: Objective Colorectal cancer (CRC) screening programmes based on the guaiac faecal occult blood test (gFOBT) reduce CRC-specific mortality. Several studies have shown higher sensitivity with the faecal immunochemical test (FIT) compared with gFOBT. We carried out an ecological study to evaluate the impact of FIT-based screening programmes on CRC mortality. Design In the Veneto Region (Italy), biennial FIT-based screening programmes that invited 50–69-year-old residents were introduced in different areas between 2002 and 2009. We compared CRC mortality rates from 1995 to 2011 between the areas where screening started in 2002–2004 (early screening areas (ESA)) and areas that introduced the screening in 2008–2009 (late screening areas (LSA)) using Poisson regression models. We also compared available data on CRC incidence rates (1995–2007) and surgical resection rates (2001–2012). Results Before the introduction of screening, CRC mortality and incidence rates in the two areas were similar. Compared with 1995–2000, 2006–2011 mortality rates were 22% lower in the ESA than in the LSA (rate ratio (RR)=0.78; 95% CI 0.68 to 0.89). The reduction was larger in women (RR=0.64; CI 0.51 to 0.80) than in men (RR=0.87; CI 0.73 to 1.04). In the ESA, incidence and surgery rates peaked during the introduction of the screening programme and then returned to the baseline (2006–2007 incidence) or dropped below initial values (surgery after 2007). Conclusions FIT-based screening programmes were associated with a significant reduction in CRC mortality. This effect took place much earlier than reported by gFOBT-based trials and observational studies.

MicroRNAs: new players in IBD

Abstract: MicroRNAs (miRNAs) are small non-coding RNAs, 18–23 nucleotides long, which act as post-transcriptional regulators of gene expression. miRNAs are strongly implicated in the pathogenesis of many common diseases, including IBDs. This review aims to outline the history, biogenesis and regulation of miRNAs. The role of miRNAs in the development and regulation of the innate and adaptive immune system is discussed, with a particular focus on mechanisms pertinent to IBD and the potential translational applications.

Tim-3 fosters HCC development by enhancing TGF-β-mediated alternative activation of macrophages

Abstract: Objective Tumour-associated macrophages (TAMs) and their alternative activation contribute greatly to the development of hepatocellular carcinoma (HCC). Tim-3 is highly expressed on macrophages and regulates macrophage functions in several conditions. However, whether Tim-3 is involved in the activation and the function of TAMs has not been reported. Design Tim-3 expression in HCC samples was evaluated by flow cytometry, immunohistochemistry and confocal analysis. We analysed the effects of Tim-3 knockdown on macrophages in growth of H22 tumour homografts in BALB/c mice. Tim-3 interference was performed by neutralising antibody, small interfering RNA or short hairpin RNA-expressing lentivirus. Cytokine production was evaluated by reverse transcription PCR, ELISA or Cytometric Bead Array. The effects of Tim-3 interference in macrophages were examined with regard to alternative activation of macrophages and proliferation and migration of Hepa1-6 cells. Cell growth curve, colony formation and transwell assays were involved to estimate cell proliferation and migration. Results Tim-3 expression was significantly increased in both peripheral blood monocytes and TAMs in patients with HCC. The Tim-3 expression in monocytes/TAMs strongly correlated with higher tumour grades and the poor survival of patients with HCC. Consistently, HCC conditioned medium or transforming growth factor-β fostered Tim-3 expression and the alternative activation of macrophages. Moreover, Tim-3 interference in macrophages significantly inhibited the alternative activation of macrophages and suppressed HCC cell growth both in vitro and in vivo. Blocking interleukin 6 reversed the Tim-3-mediated effects on HCC cell growth in vitro. Conclusions Tim-3 displays critical roles in microenvironment-induced activation and protumoral effects of TAMs in HCC. Interference of Tim-3 might be great potential in HCC therapy.

Spatial variation of the colonic microbiota in patients with ulcerative colitis and control volunteers

Abstract: Objectives The relevance of spatial composition in the microbial changes associated with UC is unclear. We coupled luminal brush samples, mucosal biopsies and laser capture microdissection with deep sequencing of the gut microbiota to develop an integrated spatial assessment of the microbial community in controls and UC. Design A total of 98 samples were sequenced to a mean depth of 31 642 reads from nine individuals, four control volunteers undergoing routine colonoscopy and five patients undergoing surgical colectomy for medically-refractory UC. Samples were retrieved at four colorectal locations, incorporating the luminal microbiota, mucus gel layer and whole mucosal biopsies. Results Interpersonal variability accounted for approximately half of the total variance. Surprisingly, within individuals, asymmetric Eigenvector map analysis demonstrated differentiation between the luminal and mucus gel microbiota, in both controls and UC, with no differentiation between colorectal regions. At a taxonomic level, differentiation was evident between both cohorts, as well as between the luminal and mucosal compartments, with a small group of taxa uniquely discriminating the luminal and mucosal microbiota in colitis. There was no correlation between regional inflammation and a breakdown in this spatial differentiation or bacterial diversity. Conclusions Our study demonstrates a conserved spatial structure to the colonic microbiota, differentiating the luminal and mucosal communities, within the context of marked interpersonal variability. While elements of this structure overlap between UC and control volunteers, there are differences between the two groups, both in terms of the overall taxonomic composition and how spatial structure is ascribable to distinct taxa.

Association between antiviral treatment and extrahepatic outcomes in patients with hepatitis C virus infection

Abstract: Objective To elucidate the association between antiviral therapy and extrahepatic outcomes in individuals infected with HCV. Methods This nationwide cohort study screened 293 480 Taiwanese residents with HCV infection and excluded those with substantial comorbidity. A total of 12 384 eligible patients who had received pegylated interferon plus ribavirin between 1 October 2003 and 31 December 2010 were enrolled in the treated cohort; they were matched 1 : 2 with 24 768 untreated controls in the propensity score and post-diagnosis treatment-free period. The incidences of end-stage renal disease (ESRD), acute coronary syndrome (ACS), ischaemic stroke and catastrophic autoimmune diseases were calculated after adjustment for competing mortality. Results The treated and untreated cohorts were followed up for a mean (±SD) duration of 3.3 (±2.5) and 3.2 (±2.4) years, respectively, until 31 December 2011. The calculated 8-year cumulative incidences of ESRD, ACS, ischaemic stroke and autoimmune catastrophes between treated and untreated patients were 0.15% vs 1.32% (p Conclusions Antiviral treatment for HCV is associated with improved renal and circulatory outcomes, but unrelated to catastrophic autoimmune diseases.