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Liver coinfection by hepatitis B virus (HBV) and hepatitis D virus (HDV) can result in a severe form of hepatocellular carcinoma with poor prognosis. Coinfection with HDV and HBV causes more deleterious effects than infection with HBV alone. Clinical research has shown that glutathione S-transferase P1 (GSTP1), a tumor suppressor gene, is typically downregulated in liver samples from hepatitis-infected patients. In the present study, our data indicated that small HDV antigen (s-HDAg) could specifically bind to GSTP1 mRNA and significantly downregulate GSTP1 protein expression. For the human fetal hepatocyte cell line L-02, cells transfected with s-HDAg, along with decreased GSTP1 expression, there was a significant accumulation of reactive oxygen species (ROS) and increased apoptotic ratios. Restoring GSTP1 expression through silencing s-HDAg via RNAi or overexpressing exogenous GSTP1 could largely recover the abnormal cell status. Our results revealed a novel potential mechanism of HDV-induced liver injury and hepatocarcinogenesis: s-HDAg can inhibit GSTP1 expression by directly binding to GSTP1 mRNA, which leads to accumulation of cellular ROS, resulting in high cellular apoptotic ratios and increased selective pressure for malignant transformation. To our knowledge, this is the first study to examine s-HDAg-specific pathogenic mechanisms through potential protein–RNA interactions.

There is limited information on the role of miR-17-92 in renal tubular pathophysiology. Therefore, the present study was performed to determine whether miR-17-92 plays a role in ischemia-reperfusion injury (IRI)-induced acute kidney injury. We originally demonstrated that miR-17-92 is up-regulated following IRI in vivo. To explore the roles of miR-17-92 in the IRI process, we first generated a renal proximal tubule-specific miR-17-92 deletion (PT-miR-17-92−/−) knockout mouse model with Cre driven by the Kap promoter. We found that PT-deficient miR-17-92 mice had more severe renal dysfunction and renal structures than their littermates. Compared with sham-operated mice, both wide-type (WT) mice and PT-miR-17-92−/− mice showed increased serum levels of creatinine and urea. However, the levels of serum urea and creatinine in PT-miR-17-92−/− mice after the IRI operation were significantly higher than the levels in WT mice. In addition, PT-miR-17-92−/− mice showed higher levels of serum potassium and phosphonium after the IRI operation. Histological analysis revealed that PT-miR-17-92−/− mice had substantial histopathologic changes, such as tubular dilation and tubular necrosis. Overexpression of miR-17-92 could partially reverse the side-effects of IRI on the proximal tubules in vivo. Furthermore, we employed a quantitative proteomic strategy and identified 16 proteins as potential targets of miR-17-92. Taken together, our findings suggested that miR-17-92 may ameliorates IRI-induced acute kidney injury. Our results indicate that pharmacologic modulation of these miRNAs may have therapeutic potential for acute kidney injury. Keywords: Acute kidney injury, Ischemia reperfusion injury, miR-17-92

Purpose Apolipoprotein E knockout (apoE−/−) mouse is one of the most popular models for cardiovascular research, especially in the study of atherosclerosis. Naturally, large amount of studies try to uncover the role of apoE in atherosclerosis, and indeed apoE plays an important role in this pathogenesis. Kidney is an organ that contains lots of capillaries and also largely expresses apoE. Moreover, a protective role of apoE in kidney as an autocrine regulator has been demonstrated previously, however, the underlying mechanism is largely unknown. Experimental design In this study, comparative proteomics is for the first time used to identify the differential proteins in kidneys of apoE−/− and wild type mice, respectively, and we try to reveal the signaling network of apoE in mice kidney using bioinformatics analysis. Results Our findings show that approximately 80 proteins are significantly differentially expressed in kidneys of apoE−/− and wild type mice, and the signaling network correlated to apoE is successfully established by employing bioinformatics assay. Conclusions and clinical relevance Taken together, we originally identify the proteins with differential expression and propose an apoE correlated molecular network in mice kidney. These findings further provide evidence of the role of apoE in mice kidney and a brand new perspective in the protection and treatment of kidney disease.

Autosomal recessive polycystic kidney disease (ARPKD), characterized by ectatic collecting duct, is an infantile form of PKD occurring in 1 in 20 000 births. Despite having been studied for many years, little is known about the underlying mechanisms. In the current study, we employed, for the first time, a MS-based comparative proteomics approach to investigate the differently expressed proteins between kidney tissue samples of four ARPKD and five control individuals. Thirty two differently expressed proteins were identified and six of the identified protein encoding genes performed on an independent group (three ARPKD subjects, four control subjects) were verified by semi-quantitative RT-PCR, and part of them were further validated by Western blot and immunohistochemistry. Moreover, similar alteration tendency was detected after downregulation of PKHD1 by small interfering RNA in HEK293T cell. Interestingly, most of the identified proteins are associated with mitochondria. This implies that mitochondria may be implicated in ARPKD. Furthermore, the String software was utilized to investigate the biological association network, which is based on known and predicted protein interactions. In conclusion, our findings depicted a global understanding of ARPKD progression and provided a promising resource of targeting protein, and shed some light further investigation of ARPKD.

Autosomal recessive polycystic kidney disease (ARPKD) is a severe inherited disorder with an incidence of 1/20 000 live births. Mutations of PKHD1 (polycystic kidney and hepatic disease gene 1) gene were identified to be responsible for ARPKD. However, the underlying molecular mechanisms remain largely unknown. MicroRNAs (miRNAs) are an abundant class of small RNAs with global effect on gene expression. Up to 30% of human protein coding genes may be regulated by miRNAs. However, to date, nothing is known regarding the role of miRNAs in PKHD1. In this study, we exploited bioinformatics to analyse the 3'UTR of PKHD1 gene and illustrated that the 3'UTR region of the gene is highly conserved in evolution. We identified about 35 candidate miRNAs within a 3738 bp window of the 3'UTR region. Of the 35 potential miRNAs, miR-365-1 emerged to post-transcriptionally modulate the expression of PKHD1. Furthermore, we demonstrated that miR-365-1 modulated PKHD1 suppressed cell–cell adhesion in part through E-cadherin. Copyright © 2012 John Wiley & Sons, Ltd.

W-Cu composite powder doped with Ce (1.5 wt.%) was prepared by mechanical alloying (MA), and the W-Cu contact material was fabricated by hot pressing sintering in an electrical vacuum furnace. The microstructure, electric conductivity, hardness, and breakdown voltage of the Ce-doped W-Cu alloy were measured and compared with a conventional W-Cu alloy prepared by powder metallurgy. The results show that microstructural refinement and uniformity can improve the breakdown behavior and the electric arc stability of the Ce-doped W-Cu contact material. Also, the Ce-doped W-Cu contact material shows the characteristic of spreading electric arc, which is beneficial to electric arc erosion.

Background Transplantation with kidneys from older living donors is on the rise, yet controversy still exists over whether the outcomes are as satisfactory as with kidneys from younger donors. Methods We retrospectively analyzed 1009 living donor kidney transplants performed at our center between 2006 and 2013. Graft and patient outcomes were compared between transplants with kidneys from old living donors (OLD, 55-65 years) (n = 264) and from young living donors (YLD, Results The age was 32.80 ± 9.71 years and 33.91 ± 5.98 years for recipient in YLD and OLD group, respectively. Death-censored graft survival at 1, 3, and 5 years was 98.8%, 97.1%, and 95.8% in patients receiving YLD kidneys, similar to the corresponding values of 97.6%, 95.5% and 95.5% in patients receiving OLD kidneys (P = 0.356). Patient survival at 1, 3, and 5 years after transplantation was also similar for patients receiving YLD kidneys (98.5%, 97.1%, and 96.7%) and for patients receiving OLD kidneys (99.6%, 99.6%, and 96.8%; P = 0.110). The OLD kidneys were not associated with increased risk of death-censored graft failure (hazard ratio, 2.5; 95% confidence interval, 0.57 to 11.11) and patient death (hazard ratio, 1.67; 95% confidence interval, 0.75 to 3.73). In addition, there is no increased graft loss or patient death for each 10-year increase in donor age. Transplantation with OLD kidneys was not associated with reduced patient or graft outcomes in the short term (≤ 12 months) or medium term (>1 year). Conclusions Graft and patient outcomes after living-donor kidney transplantation are similar in the short-term and medium-term for donors aged 55 to 65 years and for younger donors. Therefore, the use of OLD kidneys should be encouraged in China.

MicroRNAs (miRNAs) have gradually been recognized as regulators of embryonic development; however, relatively few miRNAs have been identified that regulate cardiac development. A series of recent papers have established an essential role for the miRNA-17-92 (miR-17-92) cluster of miRNAs in the development of the heart. Previous research has shown that the Friend of Gata-2 (FOG-2) is critical for cardiac development. To investigate the possibility that the miR-17-92 cluster regulates FOG-2 expression and inhibits proliferation in mouse embryonic cardiomyocytes we initially used bioinformatics to analyze 3’ untranslated regions (3’UTR) of FOG-2 to predict the potential of miR-17-92 to target it. We used luciferase assays to demonstrate that miR-17-5p and miR-20a of miR-17-92 interact with the predicted target sites in the 3’UTR of FOG-2. Furthermore, RT-PCR and Western blot were used to demonstrate the post-transcriptional regulation of FOG-2 by miR-17-92 in embryonic cardiomyocytes from E12.5-day pregnant C57BL/6J mice. Finally, EdU cell assays together with the FOG-2 rescue strategy were employed to evaluate the effect of proliferation on embryonic cardiomyocytes. We first found that the miR-17-5p and miR-20a of miR-17-92 directly target the 3’UTR of FOG-2 and post-transcriptionally repress the expression of FOG-2. Moreover, our findings demonstrated that over-expression of miR-17-92 may inhibit cell proliferation via post-transcriptional repression of FOG-2 in embryonic cardiomyocytes. These results indicate that the miR-17-92 cluster regulates the expression of FOG-2 protein and suggest that the miR-17-92 cluster might play an important role in heart development.

Hepatocellular carcinoma (HCC) is one of the most deadly diseases; metastasis and recurrence are the most important factors that affect the therapy of HCC chronically. Until now, the prognosis for the metastasis of HCC had not improved. Recently, several proteins that are related to metastasis and invasion of HCC were identified, but the effective markers still remain to be elucidated.In this study, comparative proteomics was used to study the differentially expressed proteins in two HCC cell lines MHCC97L and HCCLM9, which have low and high metastatic potentials, respectively.Our findings indicated that filamin A (FLNA) and phosphoglycerate kinase 1 (PGK1) were two significantly differentially expressed proteins, with high expression in HCCLM9 cells, and may influence the metastasis of HCC cells.Taken together with the confirmation of expression on the mRNA level, we propose the use of FLNA and PGK1 as potential markers for the progression of HCC.

Autosomal recessive polycystic kidney disease (ARPKD) is a severe inherited disorder with an incidence of 1/20 000 live births. Mutations of PKHD1 (polycystic kidney and hepatic disease gene 1) gene were identified to be responsible for ARPKD. However, the underlying molecular mechanisms remain largely unknown. MicroRNAs (miRNAs) are an abundant class of small RNAs with global effect on gene expression. Up to 30% of human protein coding genes may be regulated by miRNAs. However, to date, nothing is known regarding the role of miRNAs in PKHD1. In this study, we exploited bioinformatics to analyse the 3'UTR of PKHD1 gene and illustrated that the 3'UTR region of the gene is highly conserved in evolution. We identified about 35 candidate miRNAs within a 3738 bp window of the 3'UTR region. Of the 35 potential miRNAs, miR-365-1 emerged to post-transcriptionally modulate the expression of PKHD1. Furthermore, we demonstrated that miR-365-1 modulated PKHD1 suppressed cell-cell adhesion in part through E-cadherin.

Multiple lines of evidence have shown that the functional defect of pancreatic beta cells is the root cause of type 2 diabetes. FoxO1, a key transcription factor of fundamental cellular physiology and functions, has been implicated in this process. However, the underlying molecular mechanism is still largely unknown. Here, we show that the overexpression of FoxO1 promotes the proliferation of cultured pancreatic beta cells exposed to low nutrition, while no change in apoptosis was observed compared with the control group. Moreover, by using two specific inhibitors for PI3K and MAPK signaling, we found that FoxO1 might be the downstream transcription factor of these two pathways. Furthermore, a luciferase assay demonstrated that FoxO1 could regulate the expression of Ccnd1 at the transcription level. Collectively, our findings indicated that FoxO1 modulated by both MAPK and PI3K signaling pathways was prone to cause the proliferation, but not the apoptosis, of pancreatic beta cells exposed to low nutrition, at least partially, by regulating the expression of Ccnd1 at the transcription level.