11 research outputs found
HCC incidence after hepatitis C cure among patients with advanced fibrosis or cirrhosis: A meta-analysis
Background and aims: HCV cure reduces but does not eliminate the risk of HCC. HCC surveillance is recommended in populations where the incidence exceeds 1.5% per year. In cirrhosis, HCC surveillance should continue after HCV cure, although it is uncertain if this should be indefinite. For patients with advanced fibrosis (F3), guidelines are inconsistent in their recommendations. We evaluated the incidence of HCC after HCV cure among patients with F3 fibrosis or cirrhosis. Approach and results: This systematic review and meta-analysis identified 44 studies (107,548 person-years of follow-up) assessing the incidence of HCC after HCV cure among patients with F3 fibrosis or cirrhosis. The incidence of HCC was 2.1 per 100 person-years (95% CI, 1.9-2.4) among patients with cirrhosis and 0.5 per 100 person-years (95% CI, 0.3-0.7) among patients with F3 fibrosis. In a meta-regression analysis among patients with cirrhosis, older age (adjusted rate ratio [aRR] per 10-year increase in mean/median age, 1.32; 95% CI, 1.00-1.73) and prior decompensation (aRR per 10% increase in the proportion of patients with prior decompensation, 1.06; 95% CI, 1.01-1.12) were associated with an increased incidence of HCC. Longer follow-up after HCV cure was associated with a decreased incidence of HCC (aRR per year increase in mean/median follow-up, 0.87; 95% CI, 0.79-0.96). Conclusions: Among patients with cirrhosis, the incidence of HCC decreases over time after HCV cure and is lowest in patients with younger age and compensated cirrhosis. The substantially lower incidence in F3 fibrosis is below the recommended threshold for cost-effective screening. The results should encourage the development of validated predictive models that better identify at-risk individuals, especially among patients with F3 fibrosis
Genetic effects on gene expression across human tissues
Characterization of the molecular function of the human genome and its variation across individuals is essential for identifying the cellular mechanisms that underlie human genetic traits and diseases. The Genotype-Tissue Expression (GTEx) project aims to characterize variation in gene expression levels across individuals and diverse tissues of the human body, many of which are not easily accessible. Here we describe genetic effects on gene expression levels across 44 human tissues. We find that local genetic variation affects gene expression levels for the majority of genes, and we further identify inter-chromosomal genetic effects for 93 genes and 112 loci. On the basis of the identified genetic effects, we characterize patterns of tissue specificity, compare local and distal effects, and evaluate the functional properties of the genetic effects. We also demonstrate that multi-tissue, multi-individual data can be used to identify genes and pathways affected by human disease-associated variation, enabling a mechanistic interpretation of gene regulation and the genetic basis of diseas
Genetic effects on gene expression across human tissues
Characterization of the molecular function of the human genome and its variation across individuals is essential for identifying the cellular mechanisms that underlie human genetic traits and diseases. The Genotype-Tissue Expression (GTEx) project aims to characterize variation in gene expression levels across individuals and diverse tissues of the human body, many of which are not easily accessible. Here we describe genetic effects on gene expression levels across 44 human tissues. We find that local genetic variation affects gene expression levels for the majority of genes, and we further identify inter-chromosomal genetic effects for 93 genes and 112 loci. On the basis of the identified genetic effects, we characterize patterns of tissue specificity, compare local and distal effects, and evaluate the functional properties of the genetic effects. We also demonstrate that multi-tissue, multi-individual data can be used to identify genes and pathways affected by human disease-associated variation, enabling a mechanistic interpretation of gene regulation and the genetic basis of disease
Management of common hepatobiliary disorders in pregnancy
Liver biochemistry results can be abnormal due to changes that occur during pregnancy. Careful history taking and examination are required to establish the cause and, if a hepatobiliary disorder is present, to determine whether it is pre-existing, coincidental or related to the pregnancy
Migration route of Fasciola into the liver
A 56-year-old lady presented to an outpatient clinic with 3 weeks of upper abdominal pain. She had no significant past medical history or previous abdominal surgeries. She took no regular medications, did not smoke, and did not consume alcohol. She had recently been on a 1-month holiday, traveling with her husband and two children through Vietnam, Cambodia, Malaysia, and Singapore. She returned home to Australia 3 months ago
Prospective study of magnetic resonance spectroscopy identifies specific metabolic changes in covert hepatic encephalopathy
Novel magnetic resonance KTRANS measurement of blood-brain barrier permeability correlated with covert HE
Background: Using dynamic contrast-enhanced (DCE) MR perfusion and MR spectroscopy this study aimed to characterize the blood-brain barrier permeability and metabolite changes in patients with cirrhosis and without covert HE. Methods: Covert HE was defined using psychometric HE score (PHES). The participants were stratified into 3 groups: cirrhosis with covert HE (CHE) (PHES<-4); cirrhosis without HE (NHE) (PHES≥-4); and healthy controls (HC). Dynamic contrast-enhanced MRI and MRS were performed to assess KTRANS, a metric derivative of blood-brain barrier disruption, and metabolite parameters. Statistical analysis was performed using IBM SPSS (v25). Results: A total of 40 participants (mean age 63 y; male 71%) were recruited as follows: CHE (n=17); NHE (n=13); and HC (n=10). The KTRANS measurement in the frontoparietal cortex demonstrated increased blood-brain barrier permeability, where KTRANS was 0.01±0.02 versus 0.005±0.005 versus 0.004±0.002 in CHE, NHE, and HC patients, respectively (p = 0.032 comparing all 3 groups). Relative to HC with a value of 0.28, the parietal glutamine/creatine (Gln/Cr) ratio was significantly higher in both CHE 1.12 mmoL (p < 0.001); and NHE 0.49 (p = 0.04). Lower PHES scores correlated with higher glutamine/Cr (Gln/Cr) (r=-0.6; p < 0.001) and lower myo-inositol/Cr (mI/Cr) (r=0.6; p < 0.001) and lower choline/Cr (Cho/Cr) (r=0.47; p = 0.004). Conclusion: The dynamic contrast-enhanced MRI KTRANS measurement revealed increased blood-brain barrier permeability in the frontoparietal cortex. The MRS identified a specific metabolite signature with increased glutamine, reduced myo-inositol, and choline, which correlated with CHE in this region. The MRS changes were identifiable in the NHE cohort
The validity of adenosine triphosphate measurement in detecting endoscope contamination
Background: Endoscopic procedures are vital to gastrointestinal disease diagnosis and management, but risk infection transmission. In Australia, endoscopes undergo monthly-to-quarterly microbiological testing, to prevent patient infection. Endoscopes are used more frequently, meaning contamination may not be detected by this surveillance before infection transmission occurs.
Aim: To evaluate the use of adenosine triphosphate (ATP) measurement, alongside standard microbiological cultures, in detecting endoscope contamination before high-level disinfection. Using these results, we also aimed to confirm the efficacy of manual cleaning in reducing levels of ATP and cfu/mL.
Methods: Seventeen in-clinical-use gastroscopes and 24 in-clinical-use colonoscopes from the Liverpool Hospital Endoscopy unit were sampled across three separate cleaning stages before high-level disinfection. Colony counts and ATP measurements were then performed on these samples.
Findings: The correlation between the cfu/mL and RLU of samples collected from colonoscopes was 0.497 (95% confidence interval: 0.28–0.66; P < 0.0001). The correlation between cfu/mL and RLU for samples collected from gastroscopes was 0.377 (0.08–0.61; P = 0.0138). RLU and cfu/mL values were shown to fall significantly (P < 0.005) following precleaning and manual cleaning.
Conclusion: There was a significant correlation between ATP and cfu/mL measured from samples collected before high-level disinfection. Precleaning and manual cleaning were shown to reduce ATP and microbiological load significantly. ATP measurement can be performed within minutes with little training and produces results that are easy to interpret. These findings warrant further research on the utility of ATP measurement as a screening tool for detecting endoscope contamination after high-level disinfection
Dynamic landscape and regulation of RNA editing in mammals
Adenosine-to-inosine (A-to-I) RNA editing is a conserved post-transcriptional mechanism mediated by ADAR enzymes that diversifies the transcriptome by altering selected nucleotides in RNA molecules1. Although many editing sites have recently been discovered2,3,4,5,6,7, the extent to which most sites are edited and how the editing is regulated in different biological contexts are not fully understood8,9,10. Here we report dynamic spatiotemporal patterns and new regulators of RNA editing, discovered through an extensive profiling of A-to-I RNA editing in 8,551 human samples (representing 53 body sites from 552 individuals) from the Genotype-Tissue Expression (GTEx) project and in hundreds of other primate and mouse samples. We show that editing levels in non-repetitive coding regions vary more between tissues than editing levels in repetitive regions. Globally, ADAR1 is the primary editor of repetitive sites and ADAR2 is the primary editor of non-repetitive coding sites, whereas the catalytically inactive ADAR3 predominantly acts as an inhibitor of editing. Cross-species analysis of RNA editing in several tissues revealed that species, rather than tissue type, is the primary determinant of editing levels, suggesting stronger cis-directed regulation of RNA editing for most sites, although the small set of conserved coding sites is under stronger trans-regulation. In addition, we curated an extensive set of ADAR1 and ADAR2 targets and showed that many editing sites display distinct tissue-specific regulation by the ADAR enzymes in vivo. Further analysis of the GTEx data revealed several potential regulators of editing, such as AIMP2, which reduces editing in muscles by enhancing the degradation of the ADAR proteins. Collectively, our work provides insights into the complex cis- and trans-regulation of A-to-I editing
Exploring the phenotypic consequences of tissue specific gene expression variation inferred from GWAS summary statistics
Scalable, integrative methods to understand mechanisms that link genetic variants with phenotypes are needed. Here we derive a mathematical expression to compute PrediXcan (a gene mapping approach) results using summary data (S-PrediXcan) and show its accuracy and general robustness to misspecified reference sets. We apply this framework to 44 GTEx tissues and 100+ phenotypes from GWAS and meta-analysis studies, creating a growing public catalog of associations that seeks to capture the effects of gene expression variation on human phenotypes. Replication in an independent cohort is shown. Most of the associations are tissue specific, suggesting context specificity of the trait etiology. Colocalized significant associations in unexpected tissues underscore the need for an agnostic scanning of multiple contexts to improve our ability to detect causal regulatory mechanisms. Monogenic disease genes are enriched among significant associations for related traits, suggesting that smaller alterations of these genes may cause a spectrum of milder phenotypes