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Campylobacter concisus is an emerging enteric pathogen that is associated with inflammatory bowel disease. Previous studies demonstrated that C. concisus is non-saccharolytic and hydrogen gas (H2) is a critical factor for C. concisus growth. In order to understand the molecular basis of the non-saccharolytic and H2-dependent nature of C. concisus growth, in this study we examined the pathways involving energy metabolism and oxidative stress defence in C. concisus. Bioinformatic analysis of C. concisus genomes in comparison with the well-studied enteric pathogen Campylobacter jejuni was performed. This study found that C. concisus lacks a number of key enzymes in glycolysis, including glucokinase and phosphofructokinase, and the oxidative pentose phosphate pathway. C. concisus has an incomplete tricarboxylic acid cycle, with no identifiable succinyl-CoA synthase or fumarate hydratase. C. concisus was inferred to use fewer amino acids and have fewer candidate substrates as electron donors and acceptors compared to C. jejuni. The addition of DMSO or fumarate to media resulted in significantly increased growth of C. concisus in the presence of H2 as an electron donor, demonstrating that both can be used as electron acceptors. Catalase, an essential enzyme for oxidative stress defence in C. jejuni, and various nitrosative stress enzymes, were not found in the C. concisus genome. Overall, C. concisus is inferred to have a non-saccharolytic metabolism in which H2 is central to energy conservation, and a narrow selection of carboxylic acids and amino acids can be utilised as organic substrates. In conclusion, this study provides a molecular basis for the non-saccharolytic and hydrogen-dependent nature of C. concisus energy metabolism pathways, which provides insights into the growth requirements and pathogenicity of this species.

OPCML hypermethylation is considered a promising cancer biomarker. We examined methylation levels in the first exon of OPCML in two patient cohorts within the esophageal adenocarcinoma and gastric adenocarcinoma cascades and in a range of cell-lines using a custom PyroMark CpG assay. Methylation levels were significantly higher in esophageal tissue with histologically confirmed glandular mucosa as compared to tissue from normal esophagi or gastro-esophageal reflux disease. Higher levels of OPCML methylation were absent in the adjacent normal esophageal tissue of patients with glandular mucosa. Higher levels of methylation were confirmed in cell-lines derived from patients with adenocarcinoma, but also detected in two cell-lines with signs of dysplasia. We validated our assay by showing no differences in methylation levels in DNA extracted from blood of patients within the gastric adenocarcinoma cascade. OPCML hypermethylation is present in a subset of patients with metaplastic changes in their esophagus.

Scientific Reports 6: Article number: 38442; published online: 02 December 2016; updated: 16 February 2017. This Article contains an error in Table 4. The text in the first row ‘CON_PiiA (strain P3UCB1)’ was incorrectly given as ‘CON_PiiB (strain H17O-S1).’

IL28B polymorphisms strongly predict spontaneous and treatment-induced clearance of hepatitis C virus (HCV) infection. A recent study proposed a 32-base pair deletion in the CC-chemokine receptor 5 (CCR5) gene (CCR5-D32) interacting with the IL28B polymorphisms to influence spontaneous HCV clearance. The aim of this study was to clarify the role of CCR5-D32 in treatmentinduced clearance of chronic hepatitis C (CHC). A cross-sectional cohort of 813 Caucasian patients with CHC genotype 1 (365 responders and 448 non-responders) who had received standard of care dual therapy with interferon (IFN)-a and ribavirin (RBV) was genotyped for the CCR5-D32 and IL28B polymorphisms to examine their interaction with respect to treatment response. CCR5-D32 did not influence treatment-induced recovery to IFN-a/RBV in CHC, and did not improve prediction of sustained virological response in the context of the IL28B polymorphisms in a multivariate model. CCR5-D32 homozygotes were significantly more frequent in those with CHC than healthy controls in the European cohorts (2.9% vs 0.4%, Po0.0001), but not in Australians of European ancestry. In conclusion, CCR5-D32 does not influence treatment response in the context of IL28B polymorphisms. Although CCR5-D32 may affect viral clearance within closely controlled geographical and genetic environments, we found no effect in larger cohorts treated with dual therapy. Refereed/Peer-reviewed

Hepatitis C virus (HCV) infects 3% of the world's population. Treatment of chronic HCV consists of a combination of PEGylated interferon-alpha (PEG-IFN-alpha) and ribavirin (RBV). To identify genetic variants associated with HCV treatment response, we conducted a genome-wide association study of sustained virological response (SVR) to PEG-IFN-alpha/RBV combination therapy in 293 Australian individuals with genotype 1 chronic hepatitis C, with validation in an independent replication cohort consisting of 555 individuals. We report an association to SVR within the gene region encoding interleukin 28B (IL28B, also called IFNlambda3; rs8099917 combined P = 9.25 x 10(-9), OR = 1.98, 95% CI = 1.57-2.52). IL28B contributes to viral resistance and is known to be upregulated by interferons and by RNA virus infection. These data suggest that host genetics may be useful for the prediction of drug response, and they also support the investigation of the role of IL28B in the treatment of HCV and in other diseases treated with IFN-alpha.

The Asian Pacific Association for the Study of the Liver (APASL) set up a working party on acute-on-chronic liver failure (ACLF) in 2004, with a mandate to develop consensus guidelines on various aspects of ACLF relevant to disease patterns and clinical practice in the Asia-Pacific region. Experts predominantly from the Asia–Pacific region constituted this working party and were requested to identify different issues of ACLF and develop the consensus guidelines. A 2-day meeting of the working party was held on January 22–23, 2008, at New Delhi, India, to discuss and finalize the consensus statements. Only those statements that were unanimously approved by the experts were accepted. These statements were circulated to all the experts and subsequently presented at the Annual Conference of the APASL at Seoul, Korea, in March 2008. The consensus statements along with relevant background information are presented in this review.

The rare but potentially devastating clinical syndrome of fulminant hepatic failure has as its components severe encephalopathy and finally cerebral edema, hemodynamic instability, renal failure, coagulopathy, profound metabolic disturbances and a particular susceptibility to bacterial and fungal infection. Despite advances in medical management, fulminant hepatic failure in its most severe form carries a high mortality rate unless urgent orthotopic liver transplantation is carried out. However, availability of cadaveric donor organs is limited and, due to the rapidly progressive clinical course in many cases, a substantial proportion of patients will die or develop contraindications to transplantation before the procedure can be performed. Consequently, recent interest has centred on living donor transplantation and the possibility of providing temporary liver support, either through auxiliary partial organ transplantation, extracorporeal perfusion or transplantation of hepatocytes, to allow time for either a liver graft to become available or native liver regeneration, on which spontaneous survival ultimately depends, to occur.

The first prospective, double-blind, randomized controlled study of acetylcysteine for the treatment of patients with non-acetaminophen-induced acute liver failure supports its use in patients in the early stages of liver failure. Emergency liver transplantation still has a fundamental role in the management of patients with the most severe form of this syndrome.

Murine studies have demonstrated that the presence of indigenous gut flora is crucial for the induction of systemic immune hyporesponsiveness to antigens initially encountered within the gastrointestinal lumen. This study investigated whether increased titers of such flora, as occur in human small intestinal bacterial overgrowth, may be associated with increased suppression of systemic immune responsiveness and the possible relation between systemic and mucosal immunity in this setting. Serum total immunoglobulin (Ig), immunoglobulin subclass, and soluble interleukin-2 receptor levels and lamina propria IgA plasma cell counts were determined in 50 consecutive subjects with (N = 30) and without (N = 20) small intestinal bacterial overgrowth. Luminal IgA levels were measured in 35 of these subjects. Serum concentrations of IgG3, but not of other immunoglobulin isotypes or soluble interleukin-2 receptors, were significantly reduced in subjects with bacterial overgrowth (P < 0.0005). Small intestinal lamina propria IgA plasma cell counts (P < 0.0005) and luminal IgA concentrations (P = 0.001) were significantly increased in this group. Serum IgG3 levels were significantly inversely correlated with luminal IgA levels (P < 0.01) and fell below the lower limit of normal (0.41 g/liter) in 17/30 (56.7%) subjects with bacterial overgrowth compared to 1/20 (5.0%) subjects without (P < 0.0005). These findings document an association between small intestinal bacterial overgrowth with indigenous gut flora and reduced serum IgG3 reactivity in humans, possibly via an interaction with mucosa-related immunoregulatory mechanisms. The possibility of underlying small intestinal bacterial overgrowth should be considered in patients with serum IgG3 deficiency, especially those with compatible symptoms and/or known predisposition.

Our aim was to determine the relationshipsbetween interleukin-6 and immunoglobulin levels withinsmall intestinal luminal secretions. Twenty adultsubjects with small intestinal bacterial overgrowth (N= 13), irritable bowel syndrome (N = 4), and nonulcerdyspepsia (N = 3) underwent endoscopic aspiration ofsecretions from the small intestinal mucosal surface forassessment of IL-6, IgA1, IgA2,IgM, IgG1, IgG2, IgG3,and IgG4 concentrations. Serum immunoglobulinconcentrations and small intestinal histology were alsodetermined. IgA2 and IgG3 were thepredominant IgA1 and IgG1subclasses in luminal secretions in 19/20 (95%) and 20/20 (100%) subjects,respectively. IgA2 and IgG3predominated in serum in all subjects. No subject hadvillous atrophy. Luminal IL-6 concentrations correlatedsignificantly with luminal IgA2, IgM, and IgG3concentrations but not with IgA2 or any otherIgG3 subclass levels. Conversely, luminalIL-6 or immunoglobulin concentrations did not correlatesignificantly with levels of any immunoglobulin isotype in serum. These observations suggestthat important relationships exist between local IL-6and IgA2, IgM, and IgG3 responsesin human small intestinal luminal secretions. Localinvestigation is mandatory when assessing intestinal immuneactivity.

It is unknown whether bacteriolysis due toluminal complement activation contributes to localdefense mechanisms against small intestinal bacterialovergrowth, particularly with gramnegative bacteria.This study addressed this issue. Thirty adultsubjects were investigated with culture of luminalsecretions adherent to proximal small intestinal mucosa.Luminal and plasma concentrations of C3 and C3d andC3d/C3 ratios were determined. Activated terminalcomplement complex was sought in surface epithelium towhich aspirated secretions had been adherent. Smallintestinal bacterial overgrowth with gram-negativebacteria was present in 12/30 (40.0%) subjects. C3, C3d,and C3d/C3 profiles indicated that increased local butnot systemic C3 activation occurs in this group.Conversely, no activation of terminal complement complex was evident in this circumstance. Thus,complement-mediated bacteriolysis is unlike tocontribute to local defense mechanisms against smallintestinal bacterial overgrowth, even when overgrowthflora includes gram-negative bacteria. Factors preventing fulllocal activation of the complement cascade in thiscircumstance require investigation.

The molecular adsorbents recirculating system (MARS®) is a form of artificial liver support that has the potential to remove substantial quantities of albumin-bound toxins that have been postulated to contribute to the pathogenesis of liver cell damage, haemodynamic instability and multi-organ failure in patients with acute liver failure (ALF) and acute-on-chronic liver failure (AoCLF). These toxins include fatty acids, bile acids, tryptophan, bilirubin, aromatic amino acids and nitric oxide. Data from controlled clinical trials are limited so far. One of two studies performed on small numbers of patients with AoCLF suggest a survival benefit, but no controlled data are available in the ALF setting. Our preliminary experience with MARS therapy, instituted late in the clinical course of five patients with severely impaired liver function, including three with AoCLF precipitated by sepsis and two with liver dysfunction due to sepsis in the absence of pre-existing chronic liver disease, indicates some clinical efficacy. However, the overall survival rate (1 of 5; 20%) remained poor. More data obtained from larger cohorts of patients enrolled in randomised controlled studies will be required in both the AoCLF and ALF settings to identify categories of liver failure patients who might benefit most from MARS treatment, to ascertain the most appropriate timing of intervention and to determine the overall impact on outcome, including cost-effectiveness.