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111.
Seven new polyhydroxypregnane glycosides, named cynotophyllosides P–V, together with three known analogs were isolated from the roots of Cynanchum otophyllum C.K.Schneid . Their structures were elucidated by a variety of spectroscopic techniques, as well as acid‐catalyzed hydrolysis. All isolates were tested for their immunological activities in vitro against Con A‐ and LPS‐induced proliferation of mice splenocytes. Immunoenhancing (for 1 , 9 ) and immunosuppressive (for 2 ) activities were observed. Furthermore, cynotophylloside R ( 3 ) showed immunomodulatory as it enhanced the proliferation of splenocytes in low concentration and suppressed immune cells in concentration more than 1.0 μg/ml. 相似文献
112.
Tingting Gao Zhan Zhou Jianyong Yu Jing Zhao Guiling Wang Dianxue Cao Bin Ding Yiju Li 《Liver Transplantation》2019,9(8)
Developing advanced supercapacitors with both high areal and volumetric energy densities remains challenging. In this work, self‐supported, compact carbon composite electrodes are designed with tunable thickness using 3D printing technology for high‐energy‐density supercapacitors. The 3D carbon composite electrodes are composed of the closely stacked and aligned active carbon/carbon nanotube/reduced graphene oxide (AC/CNT/rGO) composite filaments. The AC microparticles are uniformly embedded in the wrinkled CNT/rGO conductive networks without using polymer binders, which contributes to the formation of abundant open and hierarchical pores. The 3D‐printed ultrathick AC/CNT/rGO composite electrode (ten layers) features high areal and volumetric mass loadings of 56.9 mg cm?2 and 256.3 mg cm?3, respectively. The symmetric cell assembled with the 3D‐printed thin GO separator and ultrathick AC/CNT/rGO electrodes can possess both high areal and volumetric capacitances of 4.56 F cm?2 and 10.28 F cm?3, respectively. Correspondingly, the assembled ultrathick and compact symmetric cell achieves high areal and volumetric energy densities of 0.63 mWh cm?2 and 1.43 mWh cm?3, respectively. The all‐component extrusion‐based 3D printing offers a promising strategy for the fabrication of multiscale and multidimensional structures of various high‐energy‐density electrochemical energy storage devices. 相似文献
113.
Quan Liu Johann Toudert Tengfei Li Mariia Kramarenko Guillermo Martínez‐Denegri Laura Ciammaruchi Xiaowei Zhan Jordi Martorell 《Liver Transplantation》2019,9(20)
In the subwavelength regime, several nanophotonic configurations have been proposed to overcome the conventional light trapping or light absorption enhancement limit in solar cells also known as the Yablonovitch limit. It has been recently suggested that establishing such limit should rely on computational inverse electromagnetic design instead of the traditional approach combining intuition and a priori known physical effect. In the present work, by applying an inverse full wave vector electromagnetic computational approach, a 1D nanostructured optical cavity with a new resonance configuration is designed that provides an ultrabroadband (≈450 nm) light absorption enhancement when applied to a 107 nm thick active layer organic solar cell based on a low‐bandgap (1.32 eV) nonfullerene acceptor. It is demonstrated computationally and experimentally that the absorption enhancement provided by such a cavity surpasses the conventional limit resulting from an ergodic optical geometry by a 7% average over a 450 nm band and by more than 20% in the NIR. In such a cavity configuration the solar cells exhibit a maximum power conversion efficiency above 14%, corresponding to the highest ever measured for devices based on the specific nonfullerene acceptor used. 相似文献
114.
115.
Yongkun Zhan Weicheng Chen Zhiyu Feng Chaozhong Tan Mengru Li Yangliu Song Zhengshan Zhao Wei Sheng Guoying Huang 《Genesis (New York, N.Y. : 2000)》2019,57(11-12)
Acrodysostosis is an extremely rare disorder at birth, that is, characterized by skeletal dysplasia with short stature and midfacial hypoplasia, which has been reported to be caused by PDE4D and PRKAR1A gene mutations. Here, a Chinese boy with acrodysostosis, ventricular septal defect, and pulmonary hypertension was recruited for our study, and his clinical and biochemical characteristics were analyzed. A novel de novo heterozygous missense mutation (NM_001104631: c.2030A>C, p.Tyr677Ser) of the PDE4D gene was detected by whole exome sequencing and confirmed by Sanger sequencing. The c.2030A>C (p.Tyr677Ser) variant was located in exon 15 of the PDE4D gene, predicted to be damaging by a functional prediction program and shown to be highly conserved among many species. Further functional analysis showed that the p.Tyr677Ser substitution changes the function of the PDE4D protein, affects its subcellular localization in transfected cells, increases PDE4 activity in the regulation of cAMP signaling and affects cell proliferation. Our study identified a novel de novo PDE4D mutation in acrodysostosis of Chinese origin that not only contributes a deeper appreciation of the phenotypic characteristics of patients with PDE4D mutations but also expands the spectrum of PDE4D mutations. 相似文献
116.
117.
Yongqiang Yang Ruyue Shao Rong Jiang Min Zhu Li Tang Longjiang Li Li Zhang 《Journal of biochemical and molecular toxicology》2019,33(9)
β‐Hydroxybutyrate (BHB), one of ketone body, has been traditionally regarded as an alternative carrier of energy, but recent studies found that BHB plays versatile roles in inflammation. It has been previously reported that the level BHB declined in mice with lipopolysaccharide (LPS)/d ‐galactosamine (d ‐Gal)‐induced liver damage, but the pathological significance remains unclear. In the present study, the pathophysiological roles of BHB in LPS/d ‐Gal‐induced hepatic damage has been investigated. The results indicated pretreatment with BHB further enhanced LPS/d ‐Gal‐induced elevation of aspartate aminotransferase and alanine aminotransferase, exacerbated the histological abnormalities and increased the mortality. Pretreatment with BHB upregulated the level of tumor necrosis factor α and interleukin‐6 in plasma, promoted the activities of caspase‐3, caspase‐8, and caspase‐9 and increased the count of terminal deoxynucleotidyl transferase dUTP nick end labeling‐positive cells. In addition, post‐insult supplement with BHB also potentiated LPS/d ‐Gal‐induced apoptotic liver damage. Therefore, BHB might be a detrimental factor in LPS/d ‐Gal‐induced liver injury via enhancing the inflammation and the apoptosis in the liver. 相似文献
118.
Yang Siyuan Xu Weizhi Liu Cheng Jin Jiaqi Li Xueying Jiang Yuhan Zhang Lei Meng Xianbin Zhan Jun Zhang Hongquan 《中国科学:生命科学英文版》2022,65(1):129-141
Science China Life Sciences - Large tumor suppressor 1 (LATS1) is the key kinase controlling activation of Hippo signalling pathway. Post-translational modifications of LATS1 modulate its kinase... 相似文献
119.
Zhang Feng Huang Jiacheng Guo Hao Yang Chenkun Li Yufei Shen Shuangqian Zhan Chuansong Qu Lianghuan Liu Xianqing Wang Shouchuang Chen Wei Luo Jie 《中国科学:生命科学英文版》2022,65(7):1380-1394
Science China Life Sciences - Plants produce specialized metabolites to adapt to the ever-changing environments. Flavonoids are antioxidants essential for growth, development, and breeding with... 相似文献
120.