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101.
Qiongzhen Chen Jinmeng Li Junfeng Ma Xiaoning Yang Ming Ni Yali Zhang Xiaokun Li Zhuofeng Lin Fanghua Gong 《Journal of cellular and molecular medicine》2020,24(9):5341-5351
Fibroblast growth factor 21 (FGF21), a metabolic hormone with pleiotropic effects on glucose and lipid metabolism and insulin sensitivity, alleviates the process of acute pancreatitis (AP). However, its mechanism remains elusive. The pathological and physiological characteristics of FGF21 are observed in both patients with AP and cerulein‐induced AP models, and the mechanisms of FGF21 in response to AP are investigated by evaluating the impact of autophagy in FGF21‐treated mice and cultured pancreatic cells. Circulating levels of FGF21 significantly increase in both AP patients and cerulein‐induced AP mice, which is accompanied by the change of pathology in pancreatic injury. Replenishment of FGF21 distinctly reverses cerulein‐induced pancreatic injury and improves cerulein‐induced autophagy damage in vivo and in vitro. Mechanically, FGF21 acts on pancreatic acinar cells to up‐regulate Sirtuin‐1 (Sirt1) expression, which in turn repairs impaired autophagy and removes damaged organs. In addition, blockage of Sirt1 accelerates cerulein‐induced pancreatic injury and weakens the regulative effect in FGF21‐activated autophagy in mice. These results showed that FGF21 protects against cerulein‐induced AP by activation of Sirtuin‐1‐autophagy axis. 相似文献
102.
In order to find novel antitumor candidate agents with high efficiency and low toxicity, 14 novel substituted 5‐anilino‐α‐glucofuranose derivatives have been designed, synthesized and evaluated for antiproliferative activities in vitro. Their structures were characterized by NMR (1H and 13C) and HR‐MS, and configuration (R/S) at C(5) was identified by two‐dimensional 1H,1H‐NOESY‐NMR spectrum. Their antiproliferative activities against human tumor cells were investigated by MTT assay. The results demonstrated that most of the synthesized compounds had antiproliferative effects comparable to the reference drugs gefitinib and lapatinib. In particular, (5R)‐5‐O‐(3‐chloro‐4‐{[5‐(4‐fluorophenyl)thiophen‐2‐yl]methyl}anilino)‐5‐deoxy‐1,2‐O‐(1‐methylethylidene)‐α‐glucofuranose ( 9da ) showed the most potent antiproliferative effects against SW480, A431 and A549 cells, with IC50 values of 8.57, 5.15 and 15.24 μm , respectively. This work suggested 5‐anilino‐α‐glucofuranose as an antitumor core structure that may open a new way to develop more potent anti‐cancer agents. 相似文献
103.
Qun Fan Pengfei Hou Changhyeok Choi Tai‐Sing Wu Song Hong Fang Li Yun‐Liang Soo Peng Kang Yousung Jung Zhenyu Sun 《Liver Transplantation》2020,10(5)
Electrochemical reduction of carbon dioxide (CO2) to fuels and value‐added industrial chemicals is a promising strategy for keeping a healthy balance between energy supply and net carbon emissions. Here, the facile transformation of residual Ni particle catalysts in carbon nanotubes into thermally stable single Ni atoms with a possible NiN3 moiety is reported, surrounded with a porous N‐doped carbon sheath through a one‐step nanoconfined pyrolysis strategy. These structural changes are confirmed by X‐ray absorption fine structure analysis and density functional theory (DFT) calculations. The dispersed Ni single atoms facilitate highly efficient electrocatalytic CO2 reduction at low overpotentials to yield CO, providing a CO faradaic efficiency exceeding 90%, turnover frequency approaching 12 000 h?1, and metal mass activity reaching about 10 600 mA mg?1, outperforming current state‐of‐the‐art single atom catalysts for CO2 reduction to CO. DFT calculations suggest that the Ni@N3 (pyrrolic) site favors *COOH formation with lower free energy than Ni@N4, in addition to exothermic CO desorption, hence enhancing electrocatalytic CO2 conversion. This finding provides a simple, scalable, and promising route for the preparation of low‐cost, abundant, and highly active single atom catalysts, benefiting future practical CO2 electrolysis. 相似文献
104.
Geon‐Hyoung An John Hong Sangyeon Pak Yuljae Cho Sanghyo Lee Bo Hou SeungNam Cha 《Liver Transplantation》2020,10(3)
Recent supercapacitors show a high power density with long‐term cycle life time in energy‐powering applications. A supercapacitor based on a single metal electrode accompanying multivalent cations, multiple charging/discharging kinetics, and high electrical conductivity is a promising energy‐storing system that replaces conventionally used oxide and sulfide materials. Here, a hierarchically nanostructured 2D‐Zn metal electrode‐ion supercapacitor (ZIC) is reported which significantly enhances the ion diffusion ability and overall energy storage performance. Those nanostructures can also be successfully plated on various flat‐type and fiber‐type current collectors by a controlled electroplating method. The ZIC exhibits excellent pseudocapacitive performance with a high energy density of 208 W h kg?1 and a power density from 500 W kg?1, which are significantly higher than those of previously reported supercapacitors with oxide and sulfide materials. Furthermore, the fiber‐type ZIC also shows high energy‐storing performance, outstanding mechanical flexibility, and waterproof characteristics, without any significant capacitance degradation during bending tests. These results highlight the promising possibility of nanostructured 2D Zn metal electrodes with the controlled electroplating method for future energy storage applications. 相似文献
105.
Yunzhen Wu Shuyan Cao Jungang Hou Zhuwei Li Bo Zhang Panlong Zhai Yanting Zhang Licheng Sun 《Liver Transplantation》2020,10(29)
Converting CO2 to valuable carbonaceous fuels and chemicals via electrochemical CO2 reduction by using renewable energy sources is considered to be a scalable strategy with substantial environmental and economic benefits. One of the challenges in this field is to develop nanocatalysts with superior electrocatalytic activity and selectivity for targeted products. Nonmetal species modification of nanocatalysts is of great significance for the construction of distinctive active sites to overcome the kinetic limitations of CO2 reduction. These types of modification enable the efficient control of the selectivity and significantly decrease the reaction overpotential. Herein, a comprehensive review of the recent progress of nonmetal species modification of nanocatalysts for electrochemical CO2 reduction is presented. After discussing some fundamental parameters and the basic principles of CO2 reduction, including possible reaction pathways in light of theoretical modeling and experiments, the identification of active sites and elucidation of reaction mechanisms are emphasized for unraveling the role of nonmetal species modification, such as heteroatom incorporation, organic molecule decoration, electrolyte engineering, and single‐atom engineering. In the final section, future challenges and constructive perspectives are provided, facilitating the accelerated advancement of mechanism research and practical applications of green carbon cycling. 相似文献
106.
107.
Wang Lixia Zhu Fan Yang Huansheng Li Jianzhong Li Yali Ding Xueqin Xiong Xia Ji Fengjie Zhou Hanlin Yin Yulong 《中国科学:生命科学英文版》2020,63(2):259-268
Epidermal growth factor(EGF) has been shown to improve piglet intestinal morphology and epithelial recovery. In an attempt to further understand the mechanisms behind these improvements, this study tested the hypothesis that dietary EGF may affect intestinal morphology by stimulating the proliferation and differentiation of enterocytes in weaning piglets. In piglets receiving200 μg kg–1 EGF, crypt depth and villus height increased(P0.05). Adding 400 μg kg–1 EGF increased villus height-to-crypt depth ratio(P0.05), but reduced crypt depth(P0.05). Dietary supplementation with 200 μg kg–1 EGF significantly increased the number of Ki67-positive cells(P0.01) and tended to increase the mRNA level of proliferating cell nuclear antigen(P0.10).However, this supplementation decreased the expression level of intestinal fatty acid-binding protein(P0.05). Piglets fed with400 μg kg–1 EGF had an increased mRNA level of intestinal alkaline phosphatase(P0.05). The phosphorylation of m TOR(mammalian target of rapamycin) was observed in the 200 μg kg–1 EGF group. These results suggest that dietary supplementation with a low level of EGF improved piglet intestinal morphology through stimulating the proliferation and differentiation of enterocytes, and the mTOR signaling pathway may partly be involved in this process. 相似文献
108.
109.
Shen He Wu Shuyu Chen Xi Xu Bai Ma Dezun Zhao Yannan Zhuang Yan Chen Bing Hou Xianglin Li Jiayin Cao Yudong Fu Xianyong Tan Jun Yin Wen Li Juan Meng Li Shi Ya Xiao Zhifeng Jiang Xingjun Dai Jianwu 《中国科学:生命科学英文版》2020,63(12):1879-1886
Science China Life Sciences - Spinal cord injury (SCI), especially complete transected SCI, leads to loss of cells and extracellular matrix and functional impairments. In a previous study, we... 相似文献
110.
Mao Yingyan Yang Diya Li Jing Liu Jun Hou Ruowu Zhang Zheng Yang Yiquan Tian Lei Weinreb Robert N. Wang Ningli 《中国科学:生命科学英文版》2020,63(12):1887-1894
Science China Life Sciences - The present study aims to assess the potential difference of biomechanical response of the optic nerve head to the same level of trans-lamina cribrosa pressure... 相似文献