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The diagnosis of drug-induced liver injury (DILI) is a challenging problem, often confounded by incomplete clinical information and the difficulty of eliciting exposure to herbal products, over-the-counter agents and toxins.

Background/AimsAcute hyperglycemia is known to worsen ischemia/reperfusion (I/R) injury following myocardial infarction and stroke. We investigated whether acute hyperglycemia worsens injury and amplifies the inflammatory response evoked by hepatic I/R.MethodsRats were pretreated with an intraperitoneal injection of 25% glucose or 0.9% sodium chloride (10 ml/kg BW). Subsequently, rats underwent partial (70%) hepatic ischemia for 45 min. After 4 h of reperfusion, hepatic injury, oxidative stress, inflammation, and heat shock protein expression were assessed.ResultsLiver injury was increased in the hyperglycemic group with alanine aminotransferase (ALT) and aspartate aminotransferease (AST) serum concentrations of 7,832 ± 3,374 and 10,677 ± 4,110 U/L compared to 3,245 ± 2,009 and 5,386 ± 3,393 U/L (p < 0.05 vs. control). Hyperglycemic I/R was associated with increased liver nitrotyrosine concentrations and increased neutrophil infiltration. I/R upregulated the protective heat shock proteins HSP32 and HSP70 in control animals, but this protective mechanism was inhibited by hyperglycemia: HSP32 expression decreased from 1.97 ± 0.89 (control) to 0.46 ± 0.13 (hyperglycemia), HSP70 expression decreased from 18.99 ± 11.55 (control) to 3.22 ± 0.56 (hyperglycemia), (expression normalized to sham, both p < 0.05 vs. control I/R).ConclusionsAcute hyperglycemia worsens hepatic I/R injury by amplifying oxidative stress and the inflammatory response to I/R. The increase in injury is associated with a downregulation of the protective heat shock proteins HSP32 and HSP70.

Transgenic analyses have defined two MyoD enhancers in mammals, the core enhancer and distal regulatory region (DRR); these enhancers exhibit complementary activities and together are sufficient to recapitulate MyoD expression in developing and mature skeletal muscle. DRR activity is restricted to differentiated muscle and persists postnatally, suggesting an important role in maintaining MyoD expression in myocytes and muscle fibers. Here, we use targeted mutagenesis in the mouse to define essential functions of the DRR in its normal chromosomal context. Surprisingly, deletion of the DRR resulted in reduced MyoD expression in all myogenic lineages at E10.5, at least 1 day prior to detection of DRR activity in limb buds and branchial arches of transgenic mice. At later embryonic and fetal stages, however, no defect in MyoD expression was observed, indicating that the DRR is dispensable for regulating MyoD during muscle differentiation. Expression analyses in wild-type and Myf-5 mutant embryos also indicate that the DRR is not an obligate target for Myf-5- and Pax-3-dependent regulation. In contrast to embryonic and fetal stages, deletion of the DRR resulted in a pronounced reduction in MyoD mRNA levels in adults, showing a functional requirement for DRR activity in mature muscle. These data reveal essential and redundant functions of the DRR and underscore the importance of loss-of-function enhancer analyses for understanding cis transcriptional circuitry.

Scirrhous hepatocellular carcinoma is a rare ill-defined morphological subtype of hepatocellular carcinoma characterized by marked stromal fibrosis. This variant can be difficult to distinguish from intrahepatic cholangiocarcinoma and metastatic adenocarcinoma, especially on needle biopsies. We performed immunohistochemistry for hepatocellular and adenocarcinoma-associated markers on 20 scirrhous hepatocellular carcinoma cases and compared the results with classical hepatocellular carcinoma and intrahepatic cholangiocarcinoma. Scirrhous hepatocellular carcinomas were significantly less likely to be HepPar-1 positive than classical hepatocellular carcinomas (26% and 74%, respectively; Po0.001) and were significantly more likely to express adenocarcinoma-associated markers such as epithelial cell adhesion molecule (63 vs 11%; Po0.001), cytokeratin 19 (26 vs 2%; Po0.001), and cytokeratin 7 (53 vs 2%; Po0.001). At least one of these adenocarcinoma-related markers was positive in 80% of scirrhous hepatocellular carcinoma cases. Glypican 3 and arginase were positive in 79% and 85% of cases of scirrhous hepatocellular carcinoma, respectively; the combined use of these two markers yielded 100% sensitivity for scirrhous hepatocellular carcinoma. In conclusion, the scirrhous morphology, absence of HepPar-1 staining, and frequent positivity with adenocarcinoma-related markers in scirrhous hepatocellular carcinoma can lead to an erroneous diagnosis of adenocarcinoma. Glypican 3 and arginase are the most reliable markers for identifying hepatocellular differentiation in this setting.

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INTRODUCTION: Fatty liver disease (FLD) influences liver disease progression and liver cancer risk. We investigated the impact of FLD on liver disease severity in a large North American cohort with chronic hepatitis B virus (HBV). METHODS: Liver biopsies from 420 hepatitis B surface antigen-positive adults enrolled in the Hepatitis B Research Network and who were not on HBV therapy in the previous month were evaluated for inflammation and fibrosis. Steatohepatitis was based on steatosis, hepatocyte ballooning ± Mallory-Denk bodies, and perisinusoidal fibrosis. Models evaluated factors associated with steatohepatitis, and the associations of steatohepatitis with fibrosis, and longitudinal alanine aminotransferase, aspartate aminotransferase, and Fibrosis-4. RESULTS: The median age was 42 years, 62.5% were male, and 79.5% were Asian. One hundred thirty-two (31.4%) patients had FLD (77 [18.3%] steatosis only, 55 [13.1%] steatohepatitis). Older age, overweight/obesity, and diabetes were associated with steatohepatitis. Steatohepatitis (vs no FLD) was associated with 1.68 times higher risk of advanced fibrosis at baseline (95% confidence interval, 1.12–2.51), and there was an indication of higher incident cirrhosis rate during follow-up. Steatohepatitis vs no FLD was also independently associated with, on average, 1.39 times higher alanine aminotransferase (P < 0.01) and 1.25 times higher Fibrosis-4 (P = 0.04) across 4 years. DISCUSSION: Coexisting steatosis occurred in nearly a third of adults (13% had steatohepatitis) with chronic HBV in this North American cohort who underwent liver biopsies. Steatohepatitis was associated with advanced fibrosis and higher biochemical measures of hepatic inflammation over time. Therefore, in addition to viral suppression, screening for and managing metabolic abnormalities is important to prevent disease progression in HBV.