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Brucella melitensis infection causes acute necrotizing inflammation in pregnant animals; however, the pathophysiological mechanisms leading to placentitis are unknown. Here, we demonstrate that high‐mobility group box 1 (HMGB1) acts as a mediator of placenta inflammation in B. melitensis‐infected pregnant mice model. HMGB1 levels were increased in trophoblasts or placental explant during B. melitensis infection. Inhibition of HMGB1 activity with neutralising antibody significantly reduced the secretion of inflammatory cytokines in B. melitensis‐infected trophoblasts or placenta, whereas administration of recombinant HMGB1 (rHMGB1) increased the inflammatory response. Mechanistically, this decreased inflammatory response results from inhibition of HMGB1 activity, which cause the suppression of both mitogen‐activated protein kinases and nuclear factor kappa‐light‐chain‐enhancer of activated B cells (NF‐κB) activation. Moreover, neutralising antibody to HMGB1 prevented B. melitensis infection‐induced activation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase in trophoblasts. In contrast, in vitro stimulation of trophoblasts with rHMGB1 caused activation of NADPH oxidase and increased the production of ROS, which contributes to high bacterial burden within trophoblasts or placenta. In vivo, treatment with anti‐HMGB1 antibody increases the number of Brucella survival within placenta in B. melitensis‐infected pregnant mice but successfully reduced the severity of placentitis and abortion. 相似文献
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Ziliang Chen Yuan Ha Huaxian Jia Xiaoxiao Yan Mao Chen Miao Liu Renbing Wu 《Liver Transplantation》2019,9(19)
Construction of well‐defined metal–organic framework precursor is vital to derive highly efficient transition metal–carbon‐based electrocatalyst for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in water splitting. Herein, a novel strategy involving an in situ transformation of ultrathin cobalt layered double hydroxide into 2D cobalt zeolitic imidazolate framework (ZIF‐67) nanosheets grafted with 3D ZIF‐67 polyhedra supported on the surface of carbon cloth (2D/3D ZIF‐67@CC) precursor is proposed. After a low‐temperature pyrolysis, this precursor can be further converted into hybrid composites composed of ultrafine cobalt nanoparticles embedded within 2D N‐doped carbon nanosheets and 3D N‐doped hollow carbon polyhedra (Co@N‐CS/N‐HCP@CC). Experimental and density functional theory calculations results indicate that such composites have the advantages of a large number of accessible active sites, accelerated charge/mass transfer ability, the synergistic effect of components as well as an optimal water adsorption energy change. As a result, the obtained Co@N‐CS/N‐HCP@CC catalyst requires overpotentials of only 66 and 248 mV to reach a current density of 10 mA cm?2 for HER and OER in 1.0 m KOH, respectively. Remarkably, it enables an alkali‐electrolyzer with a current density of 10 mA cm?2 at a low cell voltage of 1.545 V, superior to that of the IrO2@CC||Pt/C@CC couple (1.592 V). 相似文献
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Qinglian Wu Xian Bao Wanqian Guo Bing Wang Yunxi Li Haichao Luo Huazhe Wang Nanqi Ren 《Biotechnology advances》2019,37(5):599-615
Alternative chemicals to diverse fossil-fuel-based products is urgently needed to mitigate the adverse impacts of fossil fuel depletion on human development. To this end, researchers have focused on the production of biochemical from readily available and affordable waste biomass. This is consistent with current guidelines for sustainable development and provides great advantages related to economy and environment. The search for suitable biochemical products is in progress worldwide. Therefore, this review recommends a biochemical (i.e., medium chain carboxylic acids (MCCAs)) utilizing an emerging biotechnological production platform called the chain elongation (CE) process. This work covers comprehensive introduction of the CE mechanism, functional microbes, available feedstock types and corresponding utilization strategies, major methods to enhance the performance of MCCAs production, and the challenges that need to be addressed for practical application. This work is expected to provide a thorough understanding of the CE technology, to guide and inspire researchers to solve existing problems in depth, and motivate large-scale MCCAs production. 相似文献
67.
Molecular dynamics simulations (MDS) are employed to investigate the effects of interatomic interaction and nanostructure on wettability of water on a copper plate. In the nano scale, these simulation results showed that the contact angle gradually increases with the decreasing of the reaction parameters, which results in the decreasing of free energy on the solid-liquid interface. Therefore, it leads to that the hydrophilic material is turned into hydrophobic, which fits the results that the wettability is changed by low surface energy materials in macro scale. Furthermore, the contact angles on smooth and rough surfaces are 87° and 71.6°, respectively. That is to say that the hydrophilic will increase for hydrophilic material due to the existence of one-layer structure; it agrees with the experimental results in macro scale. 相似文献
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Xiaotian Wu Shiqi Mao Yachen Ying Christopher J.Krueger Antony K.Chen 《基因组蛋白质组与生物信息学报(英文版)》2019,17(2):119-128
Chromatin conformation,localization,and dynamics are crucial regulators of cellular behaviors. Although fluorescence in situ hybridization-based techniques have been widely utilized for investigating chromatin architectures in healthy and diseased states,the requirement for cell fix-ation precludes the comprehensive dynamic analysis necessary to fully understand chromatin activ-ities. This has spurred the development and application of a variety of imaging methodologies for visualizing single chromosomal loci in the native cellular context. In this review,we describe currently-available approaches for imaging single genomic loci in cells,with special focus on clus-tered regularly interspaced short palindromic repeats (CRISPR)-based imaging approaches. In addition,we discuss some of the challenges that limit the application of CRISPR-based genomic imaging approaches,and potential solutions to address these challenges. We anticipate that,with continued refinement of CRISPR-based imaging techniques,significant understanding can be gained to help decipher chromatin activities and their relevance to cellular physiology and pathogenesis. 相似文献
70.
Chen Qian Xu Lixia Du Tianjiao Hou Yongxin Fan Weijia Wu Qiaoli Yan Hua 《Neurochemical research》2019,44(11):2470-2481
Neurochemical Research - Neuroinflammation and brain edema are major complications in the pathophysiology of surgical brain injury (SBI). Programmed death-ligand 1 (PD-L1), an immune inhibitory... 相似文献