National Epidemiology and Evolutionary History of Four Hand,Foot and Mouth Disease-Related Enteroviruses in China from 2008 to 2016

Hand, foot and mouth disease(HFMD) is a major public health concern in China. The most predominant enteroviruses that cause HFMD have traditionally been attributed to enterovirus A71(EVA71) and coxsackievirus A16(CVA16). Since its first large outbreak in 2008, the dominant HFMD pathogens are constantly changing. In 2013 and 2015, CVA6 exceeded both EVA71 and CVA16 to become the leading cause of HFMD in some provinces. However, there still lacks a comprehensive overview on the molecular epidemiology and evolution of HFMD-related enteroviruses at the national level. In this study, we performed systematic epidemiological analyses of HFMD-related enteroviruses using the data of 64 published papers that met the inclusion criteria, and conducted phylogenetic analyses based on 12,080 partial VP1 sequences identified in China before 31 st June 2018. We found that EVA71 prevalence has decreased sharply but other enteroviruses have increased rapidly from 2008 to 2016 and that one subtype of each enterovirus is represented during the epidemic. In addition, four genotypes EVA71_C4, CVA16_B1, CVA6_D and CVA10_C are the most predominant enterovirus strains and collectively they cause over 90% of all HFMD cases in China according to the phylogenetic trees using representative partial VP1 sequences. These four major enterovirus genotypes have different geographical distributions, and they may cocirculate with other genotypes and serotypes. These results suggest that more molecular epidemiological studies should be performed on several enteroviruses simultaneously, and such information should have implications for virological surveillance, disease management, vaccine development and policy-making on the prevention and control of HFMD.     

中药毒性评价的技术方法与应用

中药的安全性近年来受到了广泛的关注和重视,但是相应的理论和实验研究还不够充分。中药的毒性是中药安全性的关键问题之一,参照国际惯例和西方植物药研究的标准规范,依据中医药理论,应用现代新技术新方法,结合基础研究的成果,制定相应的评价体系和研究规范,是解决这个关键问题的可行思路。对近年来课题组按照上述研究思路开展的有关中药毒性评价的技术方法与应用研究的结果进行了概述,希望能为中药毒性的评价方法和技术指导原则提供理论基础,也可为雷公藤等典型中毒中药的毒性研究提供研究示范,推动中药毒性研究的发展。     

Identification of NME5 as a contributor to innate resistance to gemcitabine in pancreatic cancer cells

The limited therapeutic effect of gemcitabine on pancreatic cancer is largely attributed to pre-existing or acquired resistance of the tumor cells. This study was aimed at screening for candidate resistance-related gene(s) and elucidating the underlying mechanisms. NME5 was found to be highly expressed in an innate gemcitabine-resistant human pancreatic cancer sample and the cell line PAXC002 derived from the sample. Downregulation of NME5 significantly reversed gemcitabine resistance in PAXC002 cells, whereas NME5 overexpression induced gemcitabine resistance in the pancreatic cancer cell line BxPC-3. NME5 attenuated the induction of apoptosis and cell cycle arrest induced by gemcitabine, probably accounting for the blunted sensitivity to gemcitabine. Furthermore, NME5 was demonstrated to play its role in a nuclear factor kappaB (NF-κB)-dependent manner. NME5 was capable of directly binding NF-κB, and possibly regulated its expression level in PAXC002 cells. Our results also suggest that NF-κB is a key executor of NME5 in regulating apoptosis and cell cycle. All of these data suggest that NME5 is a promising target for relieving innate gemcitabine resistance in pancreatic cancer cells.     

Autophagy maintains the integrity of endothelial barrier in LPS‐induced lung injury

Understanding the role and underlying regulation mechanism of autophagy in lipopolysaccharide‐induced lung injury (LPS‐LI) may provide potentially new pharmacological targets for treatment of acute lung injury. The aim of this study was to investigate the functional significance of autophagy in LPS‐LI. The autophagy of human pulmonary microvascular endothelial cells (HPMVECs) and mice was inhibited before they were challenged with LPS. In vitro, permeability, vitality, and the LDH release rate of the cells were detected, the zonula occluden‐1 (ZO‐1) expression and the stress fiber formation were determined. In vivo, the lung injury was assessed. We found LPS caused high permeability and increased lactate dehydrogenase (LDH) release rate, lowered viability of the cells, inhibited the ZO‐1 expression and induced stress fiber formation, these effects were further aggravated by prohibiting the level of autophagy. Consistently, in in vivo experiments, LPS‐induced serious lung injury, which was reflected as edema, leukocyte infiltration and hemorrhage in lung tissue, and the high concentration of pro‐inflammation cytokines tumor necrosis factor (TNF)‐α and interleukin (IL)‐1β in bronchoalveolar lavage fluid (BALF). Inhibiting autophagy further exacerbated LPS‐LI. It appears that autophagy played a protective role in LPS‐LI in part through restricting the injury of lung microvascular barrier.     

A sensitive and specific liquid chromatography-mass spectrometry method for determination of metacavir in rat plasma

A sensitive and specific liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) method has been developed and validated for the quantification of metacavir in rat plasma using tinidazole as an internal standard (I.S.). Following ethyl acetate extraction, the analytes were separated on a Shim-pack ODS (4.6 microm, 150 mm x 2.0 mm I.D.) column and analyzed in selected ion monitoring (SIM) mode with a positive ESI interface using the respective [M+H](+) ions, 266 for metacavir and 248 for tinidazole. The method was validated over the concentration range of 1-600 ng/mL for metacavir. Between and within-batch precisions (R.S.D.%) were all within 15% and accuracy (%) ranged from 92.2 to 105.8%. The lower limit of quantification (LLOQ) was 1 ng/mL. The extraction recovery was on average 89.8%. The validated method was used for the pharmacokinetic study of metacavir in rats.     

miR-125a regulates HAS1 and inhibits the proliferation,invasion and metastasis by targeting STAT3 in non–small cell lung cancer cells

MicroRNA-125a (miR-125a) is related to the occurrence, development, and prognosis of various cancers according to relevant reports. However, its function role and mechanism in non–small cell lung cancer (NSCLC) is yet to be explored. Herein, we investigated the role and preliminary mechanism of miR-125a in NSCLC. First, miR-125a was noticeably downregulated in NSCLC tissues in contrast to adjacent normal tissues through the real-time quantitative polymerase chain reaction (RT-qPCR) assay. The inverted result was observed on the STAT3 and HAS1 expressions. Moreover, miR-125a was expressed at highest level in A549 among four human NSCLC cell lines. Second, functional studies indicated miR-125a restrained proliferation, invasion, migration, metastasis, and advocated apoptosis of NSCLC cells, but had no obvious effect on cell cycle. Next, results indicated that a target of miR-125a was STAT3 on the basis of prediction and confirmation by the dual-luciferase reporter assay. RT-qPCR and Western blot assays displayed that miR-125a overexpression conspicuously constrained STAT3 expression at messenger RNA and protein levels. Finally, the binding between HAS1 promoter region and STAT3 was predicted by PROMO database analysis and verified by chromatin immunoprecipitation assay, suggesting that STAT3 was bound with the HAS1 promoter regions. STAT3 overexpression exerted positive effects on HAS1 expression at protein and mRNA levels. Additionally, HAS1-related functional studies illustrated HAS1 pronouncedly suppressed the proliferative, invasive, and migratory potential of NSCLC cells in vitro. Collectively, our findings demonstrated that miR-125a prohibited the proliferation, invasion, and migration of NSCLC cells by HAS1 expression reduction as a result of inhibiting STAT3 expression in NSCLC. This study indicated that miR-125a might be of potential or value for NSCLC treatment.