β-defensin 1 expression in HCV infected liver/liver cancer: an important role in protecting HCV progression and liver cancer development

Abstract β-defensin family plays a role in host defense against viral infection, however its role in HCV infection is still unknown. In this study, we demonstrated that β-defensin 1 was significantly reduced in HCV-infected liver specimens. Treatment with interferon and ribavirin upregulated β-defensin-1, but not other β-defensin tested, with the extent and duration of upregulation associated with treatment response. We investigated β-defensin family expression in liver cancer in publicly available datasets and found that among all the β-defensins tested, only β-defensin 1 was significantly downregulated, suggesting β-defensin 1 plays a crucial role in liver cancer development. Further analysis identified E-cadherin as the top positive correlated gene, while hepatocyte growth factor-regulated tyrosine kinase substrate as the top negative correlated gene. Expression of two proteoglycans were also positively correlated with that of β-defensin 1. We have also identified small molecules as potential therapeutic agents to reverse β-defensin 1-associated gene signature. Furthermore, the downregulation of β-defensin 1 and E-cadherin, and upregulation of hepatocyte growth factor-regulated tyrosine kinase substrate, were further confirmed in liver cancer and adjacent normal tissue collected from in-house Chinese liver cancer patients. Together, our results suggest β-defensin 1 plays an important role in protecting HCV progression and liver cancer development

Prevalence and trend of hepatitis C virus infection among blood donors in Chinese mainland: a systematic review and meta-analysis

<p>Abstract</p> <p>Background</p> <p>Blood transfusion is one of the most common transmission pathways of hepatitis C virus (HCV). This paper aims to provide a comprehensive and reliable tabulation of available data on the epidemiological characteristics and risk factors for HCV infection among blood donors in Chinese mainland, so as to help make prevention strategies and guide further research.</p> <p>Methods</p> <p>A systematic review was constructed based on the computerized literature database. Infection rates and 95% confidence intervals (95% CI) were calculated using the approximate normal distribution model. Odds ratios and 95% CI were calculated by fixed or random effects models. Data manipulation and statistical analyses were performed using STATA 10.0 and ArcGIS 9.3 was used for map construction.</p> <p>Results</p> <p>Two hundred and sixty-five studies met our inclusion criteria. The pooled prevalence of HCV infection among blood donors in Chinese mainland was 8.68% (95% CI: 8.01%-9.39%), and the epidemic was severer in North and Central China, especially in Henan and Hebei. While a significant lower rate was found in Yunnan. Notably, before 1998 the pooled prevalence of HCV infection was 12.87% (95%CI: 11.25%-14.56%) among blood donors, but decreased to 1.71% (95%CI: 1.43%-1.99%) after 1998. No significant difference was found in HCV infection rates between male and female blood donors, or among different blood type donors. The prevalence of HCV infection was found to increase with age. During 1994-1995, the prevalence rate reached the highest with a percentage of 15.78% (95%CI: 12.21%-19.75%), and showed a decreasing trend in the following years. A significant difference was found among groups with different blood donation types, Plasma donors had a relatively higher prevalence than whole blood donors of HCV infection (33.95% <it>vs </it>7.9%).</p> <p>Conclusions</p> <p>The prevalence of HCV infection has rapidly decreased since 1998 and kept a low level in recent years, but some provinces showed relatively higher prevalence than the general population. It is urgent to make efficient measures to prevent HCV secondary transmission and control chronic progress, and the key to reduce the HCV incidence among blood donors is to encourage true voluntary blood donors, strictly implement blood donation law, and avoid cross-infection.</p

Electron microscopic investigation of the bactericidal action of electrochemical disinfection in comparison with chlorination, ozonation and Fenton reaction

Laboratory experiments were carried out to investigate the mechanisms of electrochemical (EC) disinfection of artificial wastewater contaminated by Escherichia coli culture. Comparative disinfection tests with chlorine, ozone and hydroxyl (·OH-) radicals produced by the Fenton reaction were also conducted. It was demonstrated that the EC process was highly effective for wastewater disinfection. Investigation with scanning electron microscopy (SEM) showed different appearances of damage to in the surface morphology and structure of the cells after different forms of disinfection. Substantial leakage of intracellular materials was found for the E. coli cells after EC disinfection, which was also observed for the cells treated by the Fenton reaction. However, such cell lysis was noticeable to a less extent for the ozonated cells and hardly noticeable for the chlorinated cells. Electron microscopic examination suggested that the cells were likely inactivated during the EC process by the chemical products with an oxidising power similar to that of hydroxyl radicals and much stronger than that of chlorine. The SEM results support the hypothesis that the predominant killing action of EC disinfection is provided by high-energy intermediate EC products. Therefore, in addition to electro-chlorination, the great capacity of EC disinfection may be attributable to the generation of short-lived germicidal agents, such as free radicals. © 2003 Elsevier Ltd. All rights reserved.link_to_subscribed_fulltex

Electrochemical wastewater disinfection: Identification of its principal germicidal actions

Laboratory experiments were carried out to investigate the mechanisms of electrochemical (EC) wastewater disinfection. Artificial wastewater contaminated by Escherichia coli (E. coli) culture, and which contained different salts of NaCl, Na 2SO 4, and NaNO 3, was used as the test medium. The experimental results do not favor the hypotheses that the EC bactericidal action was due to cell destruction by the electric field and the production of persulfate. In comparison to direct chlorination, the EC process displayed a much stronger disinfecting capability than that of electrochlorination assumed for EC disinfection. Observations with scanning electron microscopy on the E. coli bacteria of wastewater treated by different means of disinfection suggested that the cells were likely killed during the EC treatment by chemical products with oxidizing and germicidal powers similar to that of ozone and much stronger than that of chlorine. All of the findings support the theory that the major killing function of EC disinfection is provided by short-lived and high-energy intermediate EC products, such as free radicals. © ASCE.link_to_subscribed_fulltex

Proteomic identification of microRNA-122a target proteins in hepatocellular carcinoma

microRNA-122a (miR-122a) is a liver-specific miRNA that is frequently downregulated in hepatocellular carcinoma (HCC). The exact functional role of miR-122a and its target in HCC remain largely unknown. We developed a lentiviral vector for the expression of pre-miR-122a (Lenti-miR-122a). Lenti-miR-122a inhibited HCC cell growth and induced apoptosis in vitro. We employed proteomic profiling to identify the target proteins of miR-122a. In total, ten proteins with differential expression in HCC cells infected with Lenti-miR-122a were identified. Amongst them, downregulation of peroxiredoxin 2 (PRDXII) by miR-122a was validated by Western blotting. Using bioinformatics analysis, predictable target sites of miR-122a were identified in the 5′-UTR of PRDXII mRNA. Luciferase reporter assay confirmed the regulation of miR-122a on 5′-UTR of PRDXII. In conclusion, PRDXII was identified to be the new target of miR-122a. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.link_to_subscribed_fulltex

The Intermetallic Catalysts for Oxidative Esterification of Methacrolein to Methyl Methacrylate

A series of supported intermetallic Pb-Pb catalysts were prepared with the impregnation method by changing the support(silica,molecular sieve or &gamma;-alumina)and the pore size.The chemical states of the two metals were characterized by XPS analysis,the process for producing methyl methacrylate based on the direct oxidative esterification of methacrolein with methanol in the presence of oxygen was performed in a slurry reactor with the above-mentioned catalysts.The influence of the calcination temperature and the kinds of support as well as the pore size on catalytic activity had been extensively investigated.Under the conditions of temperature at 80℃,catalyst 3.8%(&omega;)and the reaction time 2 h,the conversion rate of methacrolein reached 85%,the selectivity and the yield of methyl methacrylate were 90% and 76.5%,respectively