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Objective. Gram-negative bloodstream infections (GNBSIs), especially those caused by antibiotic-resistant species, have become a public health challenge. Procalcitonin (PCT) showed promising potential in early diagnosis of GNBSI; however, little was known about its performance under different clinical settings. We here systematically assessed the diagnostic accuracy of PCT in recognizing GNBSI and made direct comparisons with C-reactive protein (CRP) and interleukin 6 (IL-6). Methods. PubMed, Embase, ISI Web of Knowledge, and Scopus were searched from inception to March 15th, 2019. Area under the summary receiver operating characteristic curve (AUC), pooled sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated. Hierarchical summary receiver operating characteristic (HSROC) model was used for the investigation of heterogeneity and for comparisons between markers. Results. 25 studies incorporating 50933 suspected BSI episodes were included. Pooled sensitivity and specificity for PCT were 0.71 and 0.76, respectively. The overall AUC was 0.80. The lowest AUCs were found in patients with febrile neutropenia (0.69) and hematological malignancy (0.69). The highest AUC was found in groups using electrochemiluminescence immunoassay (0.87). In direct comparisons, PCT showed better overall performance than CRP with the AUC being 0.85 (95% CI 0.81–0.87) for PCT and 0.78 (95% CI 0.74–0.81) for CRP, but the relative DORs varied with thresholds between PCT and CRP (p<0.001). No significant difference was found either in threshold (p=0.654) or in accuracy (p=0.480) between PCT and IL-6 in diagnosing GNBSI. Conclusions. PCT was helpful in recognizing GNBSI, but the test results should be interpreted carefully with knowledge of patients’ medical condition and should not serve as the only criterion for GNBSI. Further prospective studies are warranted for comparisons between different clinical settings.

Hepatic copper determination is an important test for the diagnosis of Wilson's disease (WD). However, the method has not been standardized, the diagnostic accuracy has not been evaluated prospectively, and the optimal cut‐off value remains controversial. Accordingly, we aimed to prospectively evaluate the diagnostic accuracy of hepatic copper content, as determined using the entire core of a liver biopsy sample. Patients for whom a liver biopsy was indicated were consecutively enrolled. Hepatic copper content was determined with atomic absorption spectroscopy. All assays were performed using careful quality control by a single technician. WD diagnosis was based on WD score or its combination with clinical follow‐up results. A total of 3,350 consecutive patients underwent liver biopsy. Six hundred ninety‐one patients, including 178 with WD, underwent two passes of liver biopsy with hepatic copper determination. Mean hepatic content in WD patients was 770.6 ± 393.2 μg/g dry weight (wt). Sensitivity, specificity, and positive and negative predictive values of hepatic copper content for WD diagnosis in the absence of primary biliary cirrhosis (PBC) or primary sclerosing cholangitis at the cut‐off value of 250 μg/g dry wt. were 94.4%, 96.8%, 91.8%, and 97.8%, respectively. The most useful cut‐off value was 209 μg/g dry wt, with a sensitivity and specificity of 99.4% and 96.1%, respectively. A total of 23.3% of patients without WD and PBC had hepatic copper content >75 μg/g dry wt. Conclusion: A liver biopsy sample of more than 1 mg dry wt may reliably reflect hepatic copper content and should be used for hepatic copper determination. Hepatic copper determination is a very valid procedure for the diagnosis of WD, and the most useful cut‐off value is 209 μg/g dry wt.(Hepatology 2015;62:1731–1741)

To explore hepatitis C virus (HCV) non-structural protein 5A (NS5A)'s influence on inhibition of AFP expression executed by p53 protein and its possible molecular mechanism.Plasmid transfection and MEIA were employed to observe p53's inhibitive effect on AFP expression of Huh7 cells and the HCV NS5A's influence on p53 function. Western blot was employed to find out if HCV NS5A affects p53 protein expression and GST pull down assay was applied to examine the interaction between HCV NS5A and p53.The AFP concentration in the supernatant of the culture of the Huh7 cells transfected with pRc/CMV was (14322+/-2412) ng/ml, and that of the Huh7 cells transfected with pCNS5A was (13843+/-3218) ng/ml; no significant difference existed between these two groups (t = 1.42, P0.05). After transfection with pC53-NS3, the AFP level was decreased to (10 241+/-1326) ng/ml, and in comparison to the above two groups it had a statistically significant difference (t values were 2.41 and 2.38, P0.05). When co-transfected with pCNS5A and pC53-NS3, the AFP expression (14582+/-1238) ng/ml returned to the level of pRc/CMV transfected, and there was a remarkably significant difference between this and that of the pC53-NS3 transfected cells (t = 3.12, P0.01). HCV NS5A had no function on the p53 protein expression with Western blot experiment. In the GST pull down assay, an HCV NS5A protein band was found after GST-p53 was added, but not detected with GST only.We found that p53 has an inhibitive function on the AFP expression in Huh7 cells and HCV NS5A minimized this p53 function. HCV NS5A did not affect p53 protein expression, but was able to form a complex with p53, by which HCV NS5A inactivated this p53 function.

AIM: To evaluate the inhibition effect of HCV NS5A on p53 transactivation on p21 promoter and explore its possible mechanism for influencing p53 function. METHODS: p53 function of transactivation on p21 promoter was studied with a luciferase reporter system in which the luciferase gene is driven by p21 promoter, and the p53-DNA binding ability was observed with the use of electrophoretic mobility-shift assay (EMSA). Lipofectin mediated p53 or HCV NS5A expression vectors were used to transfect hepatoma cell lines to observe whether HCV NS5A could abrogate the binding ability of p53 to its specific DNA sequence and p53 transactivation on p21 promoter. Western blot experiment was used for detection of HCV NS5A and p53 proteins expression. RESULTS: Relative luciferase activity driven by p21 promoter increased significantly in the presence of endogenous p53 protein. Compared to the control group, exogenous p53 protein also stimulated p21 promoter driven luciferase gene expression in a dose-dependent way. HCV NS5A protein gradually inhibited both endogenous and exogenous p53 transactivation on p21 promoter with increase of the dose of HCV NS5A expression plasmid. By the experiment of EMSA, we could find p53 binding to its specific DNA sequence and, when co-transfected with increased dose of HCV NS5A expression vector, the p53 binding affinity to its DNA gradually decreased and finally disappeared. Between the Huh 7 cells transfected with p53 expression vector alone or co-transfected with HCV NS5A expression vector, there was no difference in the p53 protein expression. CONCLUSION: HCV NS5A inhibits p53 transactivation on p21 promoter through abrogating p53 binding affinity to its specific DNA sequence. It does not affect p53 protein expression.