H型血管在骨质疏松症中的研究进展

骨质疏松症是一种全身性骨病,具有骨微结构退化、骨密度低的特点,在世界范围内发病率较高。随着我国人口逐渐进入老龄化,骨质疏松症的发病率日益上升,已经成为威胁老年人群生活质量的重要因素,给公共卫生系统带来了难以预料的挑战。近年来,许多文献报道骨内特殊型血管——H型血管生成与骨生成之间存在耦合,为骨质疏松症的治疗提供了新的研究目标。本文就H型血管的结构及功能、参与H型血管生成与成骨的细胞因子以及其他因素做一综述。     

三七植物化学成分及药理作用研究进展

三七（Panax notoginseng（Burk.）F. H. Chen）含有皂苷类、多糖类、黄酮类、炔类、醇类等结构不同的 多种化学成分,其有效成分以皂苷类和三七素为主,具有止血、活血、补血、抗血栓、保护心肌等多种药理作用,已被广泛用于临床疾病的治疗中。本文针对三七的应用现状,结合国内外相关文献,综述了三七皂苷及多糖类的主要活性成分类型,分别比较了三七皂苷及多糖的提取工艺,概述了三七活性成分在抗炎、抗肿瘤、提高免疫力、活血化瘀等方面的药理作用。为加强三七多糖的研究,优化三七活性物质提取工艺,完善三七总皂苷与其它药用成分配伍体系,进而加快三七植物的综合开发提供参考。     

从痈论治消化性溃疡

消化性溃疡具有病程长,易复发的特点,对于消化性溃疡的治疗,应始终抓住"扶正祛邪兼顾"的治疗思想,引入中医外科疮疡内治法"消、托、补"的治疗原则,药力直达病所,消痈生肌、祛瘀生新以达到抑灭幽门螺杆菌,清除坏死组织,促进溃疡面肉芽组织增生及黏膜上皮细胞修复,治愈消化性溃疡病。在清热解毒消痈的同时,不忘顾护脾胃之气;对局部痈疡修复的同时,不忘调节人体正气,以加速创口愈合,祛腐生新,减少溃疡的复发。     

β-Catenin Preserves the Stem State of Murine Bone Marrow Stromal Cells Through Activation of EZH2

During bone marrow stromal cell (BMSC) differentiation, both Wnt signaling and the development of a rigid cytoskeleton promote commitment to the osteoblastic over adipogenic lineage. β-catenin plays a critical role in the Wnt signaling pathway to facilitate downstream effects on gene expression. We show that β-catenin was additive with cytoskeletal signals to prevent adipogenesis, and β-catenin knockdown promoted adipogenesis even when the actin cytoskeleton was depolymerized. β-catenin also prevented osteoblast commitment in a cytoskeletal-independent manner, with β-catenin knockdown enhancing lineage commitment. Chromatin immunoprecipitation (ChIP)-sequencing demonstrated binding of β-catenin to the promoter of enhancer of zeste homolog 2 (EZH2), a key component of the polycomb repressive complex 2 (PRC2) complex that catalyzes histone methylation. Knockdown of β-catenin reduced EZH2 protein levels and decreased methylated histone 3 (H3K27me3) at osteogenic loci. Further, when EZH2 was inhibited, β-catenin's anti-differentiation effects were lost. These results indicate that regulating EZH2 activity is key to β-catenin's effects on BMSCs to preserve multipotentiality. © 2020 American Society for Bone and Mineral Research.     

Robust H∞ output feedback design for networked control systems with partially known delay probabilities

This article develops a predictive robust H_∞ static output feedback control approach for networked control systems where random network-induced delays in both forward and feedback communication channels are modeled as two mutually uncorrelated Markov chains. By making use of the system augmentation method, the closed-loop system is formulated as a singular Markovian jump system with two modes, wherein the transition probability matrices of the underlying Markov chains are considered to be partially accessible. Necessary and sufficient conditions for the stochastic admissibility and robust H_∞ performance of the closed-loop system are given under the assumption of partially known transition probability matrices. A linear matrix inequality condition is proposed to determine the two-mode-dependent static output feedback controller gains to compensate for the random network-induced delays efficiently and provide the desired control performance. Finally, a numerical example is provided to demonstrate the effectiveness of the proposed approach.     

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Influenza A (H1N1) viruses are distributed worldwide and pose a threat to public health. Swine, as a natural host and mixing vessel of influenza A (H1N1) virus, play a critical role in the transmission of this virus to humans. Furthermore, swine influenza A (H1N1) viruses have provided all eight genes or some genes to the genomes of influenza strains that historically have caused human pandemics. Hence, persistent surveillance of influenza A (H1N1) virus in swine herds could contribute to the prevention and control of this virus. Here, we report a novel reassortant influenza A (H1N1) virus generated by reassortment between 2009 pandemic H1N1 viruses and swine viruses. We also found that this virus is prevalent in swine herds in Shandong Province, eastern China. Our findings suggest that surveillance of the emergence of the novel reassortant influenza A (H1N1) virus in swine is imperative.     

The PB2 and M genes are critical for the superiority of genotype S H9N2 virus to genotype H in optimizing viral fitness of H5Nx and H7N9 avian influenza viruses in mice

Genotype S H9N2 avian influenza virus, which has been predominant in China since 2010, contributed its entire internal gene cassette to the genesis of novel reassortant influenza viruses, including H5Nx, H7N9 and H10N8 viruses that pose great threat to poultry and humans. A key feature of the genotype S H9N2 virus is the substitution of G1‐like M and PB2 genes for the earlier F/98‐like M and PB2 of genotype H virus. However, how this gene substitution has influenced viral adaptability of emerging influenza viruses in mammals remains unclear. We report here that reassortant H5Nx and H7N9 viruses with the genotype S internal gene cassette displayed enhanced replication and virulence over those with genotype H internal gene cassette in cell cultures as well as in the mouse models. We showed that the G1‐like PB2 gene was associated with increased polymerase activity and improved nuclear accumulation compared with the F/98‐like counterpart, while the G1‐like M gene facilitated effective translocation of RNP to cytoplasm. Our findings suggest that the genotype S H9N2 internal gene cassette, which possesses G1‐like M and PB2 genes, is superior to that of genotype H, in optimizing viral fitness, and thus have implications for assessing the potential risk of these gene introductions to generate emerging influenza viruses.     

Knocking-out of H1F1α gene by CRISPR/cas9 inhibits proliferation and invasiveness of prostate cancer DU145 cellsCSCD

Objective To explore the role of H1F1α gene in prostate cancer cell line DU145 by knocking it out with a novel gene-editing tool CRISPR/cas9 system. Methods A CRISPR/cas9 system with two sgRNAs targeting exon 1 of the H1F1α gene was constructed for the knock out experiment. CCK8 assay and transwell experiment were carried out to assess the effect of the knock out on the proliferation, migration and invasiveness of DU145 cells. Results The efficiency of gene-targeting was measured through a T7E1 assaying and sequence analysis, which confirmed that the partial knock out was successful and has led to a significant decrease in the expression of H1F1α and inhibition of cell proliferation, migration and invasiveness. Conclusion A CRISPR/cas9 system for the knock out of H1F1α has been successfully constructed, which could inhibit the proliferation and migration of DU145 cells. The system can facilitate further studies of the H1F1α gene and its roles in tumorigenesis. © 2018 West China University of Medical Sciences. All rights reserved.