The developmental types of secretory cavities in Citrus remain controversial. The relationship between secretory cavity development and the accumulation of essential oil in fruits of Citrus species is also unknown. In...The developmental types of secretory cavities in Citrus remain controversial. The relationship between secretory cavity development and the accumulation of essential oil in fruits of Citrus species is also unknown. In order to develop better insights into these problems, histological, histochemical, and cytochemical methods were used to investigate secretory cavity development and the accumulation of essential oll at different developmental stages of fruits of Citrus medica L. var. sarcodactylis （Noot.） Swingle. The results indicate that the secretory cavity of the variety seemed to originate from an epidermal cell and a subepldermal cell. These two cells underwent successive divisions, resulting In the formation of two parts： （Ⅰ） a conical cap; and （Ⅱ） a globular gland. The formation of the lumen was schlzolysigenous. Regular changes in the size of vacuoles and the accumulation of essential oil were revealed during the process of secretory cavity development. In addition, when fruits were a light yellow or golden color, the structure of secretory cavities was well developed and the content of essential oil in a single fruit reached a maximum. It would be most appropriate to collect the fruit as a medicinal material at this time.展开更多
Lithium-sulfur(Li-S)batteries have been regarded as promising energy-storage systems,due to their high theoretical capacity and energy density.However,the carbonaceous sulfur hosts suffer from weak binding force betwe...Lithium-sulfur(Li-S)batteries have been regarded as promising energy-storage systems,due to their high theoretical capacity and energy density.However,the carbonaceous sulfur hosts suffer from weak binding force between the hosts and polysulfides,restricting the cyclic stability of sulfur electrode.Meantime,the presence of binder and conductive agent in the traditional electrode reduces its energy density.This study demonstrates that titanium nitride(TiN)nanorod array on carbon cloth(CC)is employed as a flexible host for highly stable Li-S batteries via solvothermal synthesis-nitridation strategy.On the one hand,the flexible integrated network composed of three-dimensional TiN nanorod array and CC significantly improves the conductivity,increases the electron transport and electrolyte penetration of cathode.On the other hand,the 3D structure of TiN/CC and the enhanced polarity of TiN effectively strengthen the physical and chemical double adsorption for polysulfides.As a result,the combination of TiN nanorod array and CC synergistic ally promotes sulfur utilization and electrochemical performances of S@TiN/CC cathode.A discharge capacity of1015.2 mAh·g^(-1)at 0.5C after 250 cycles and 604.1mAh·g^(-1)at 3C after 250 cycles is realized.Under a larger current density of 5C,the resulting S@TiN/CC cathode maintains a high discharge capacity of 666.6 mAh·g^(-1)and the Coulombic efficiency of about 100%.展开更多
以程序性死亡配体1/程序性死亡受体1(programmed cell death ligand 1/programmed cell death protein 1,PD-L1/PD-1)免疫检查点阻断治疗为代表的肿瘤免疫疗法在临床上取得了令人鼓舞的治疗效果。小分子肿瘤免疫治疗药物与免疫检查点抗...以程序性死亡配体1/程序性死亡受体1(programmed cell death ligand 1/programmed cell death protein 1,PD-L1/PD-1)免疫检查点阻断治疗为代表的肿瘤免疫疗法在临床上取得了令人鼓舞的治疗效果。小分子肿瘤免疫治疗药物与免疫检查点抗体药物的联用,为肿瘤治疗提供了新策略。因此,研发能阻断PD-L1/PD-1免疫检查点相互作用的小分子药物是下一代肿瘤免疫疗法的新方向。本研究对丹酚酸B(salvianolic acid B,SAB)下调肿瘤细胞中PD-L1表达发挥抗肿瘤作用及机制进行了研究。利用Western blot、流式细胞术、PD-1/PD-L1相互作用分析SAB对结肠癌细胞RKO和前列腺癌细胞PC3细胞内和膜表面PD-L1蛋白表达水平的影响;荧光定量PCR检测SAB对PD-L1 mRNA的影响;细胞阻抗法和结晶紫法检测SAB对人类外周血单核细胞(peripheral blood mononuclear cell,PBMC)杀伤肿瘤细胞的效果;表面等离子共振技术分析SAB与泛素羧基末端水解酶2(ubiquitin carboxyl-terminal hydrolase 2,USP2)的直接相互作用;MC38荷瘤小鼠(所有动物实验均遵循中国医学科学院医药生物技术研究所伦理委员会的规定)检测SAB的体内抑瘤效果。结果表明,SAB能分别以浓度依赖性和时间依赖性方式下调RKO、PC3细胞中以及细胞膜表面PD-L1的水平,这与SAB抑制肿瘤细胞中去泛素化酶USP2的活性有关。机制研究发现,SAB可与USP2发生直接相互作用并抑制其去泛素化酶活性,从而促进PD-L1发生泛素-蛋白酶体途径降解。此外,SAB可促进共培养的PBMC对RKO细胞的杀伤作用。小鼠荷瘤实验证实,SAB可显著抑制C57BL/6小鼠中MC38移植瘤的生长。20 mg·kg^(-1) SAB处理荷瘤小鼠后,可使瘤体积减少63.2%。以上结果说明,SAB通过直接结合USP2并抑制其活性,促进PD-L1发生泛素-蛋白酶体途径降解,从而发挥抗肿瘤作用。本研究为将SAB研发成靶向USP2-PD-L1轴的小分子肿瘤免疫治疗药物奠定了基础。展开更多
基金Supported by the National Natural Science Foundation of China （30270083） and Science and Technology Key Program of Guangdong Province of China （2002C20147, C20605）.
文摘The developmental types of secretory cavities in Citrus remain controversial. The relationship between secretory cavity development and the accumulation of essential oil in fruits of Citrus species is also unknown. In order to develop better insights into these problems, histological, histochemical, and cytochemical methods were used to investigate secretory cavity development and the accumulation of essential oll at different developmental stages of fruits of Citrus medica L. var. sarcodactylis （Noot.） Swingle. The results indicate that the secretory cavity of the variety seemed to originate from an epidermal cell and a subepldermal cell. These two cells underwent successive divisions, resulting In the formation of two parts： （Ⅰ） a conical cap; and （Ⅱ） a globular gland. The formation of the lumen was schlzolysigenous. Regular changes in the size of vacuoles and the accumulation of essential oil were revealed during the process of secretory cavity development. In addition, when fruits were a light yellow or golden color, the structure of secretory cavities was well developed and the content of essential oil in a single fruit reached a maximum. It would be most appropriate to collect the fruit as a medicinal material at this time.
基金financially supported by the National Natural Science Foundation of China (Nos.22179064,91963119,21805140,51772157,21905141,22203046 and62174087)China Postdoctoral Science Foundation (No.2018M642287)+2 种基金Jiangsu Province Postdoctoral Research Grant Program (No.2018K156C)Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM)the Synergetic Innovation Center for Organic Electronics and Information Displays。
文摘Lithium-sulfur(Li-S)batteries have been regarded as promising energy-storage systems,due to their high theoretical capacity and energy density.However,the carbonaceous sulfur hosts suffer from weak binding force between the hosts and polysulfides,restricting the cyclic stability of sulfur electrode.Meantime,the presence of binder and conductive agent in the traditional electrode reduces its energy density.This study demonstrates that titanium nitride(TiN)nanorod array on carbon cloth(CC)is employed as a flexible host for highly stable Li-S batteries via solvothermal synthesis-nitridation strategy.On the one hand,the flexible integrated network composed of three-dimensional TiN nanorod array and CC significantly improves the conductivity,increases the electron transport and electrolyte penetration of cathode.On the other hand,the 3D structure of TiN/CC and the enhanced polarity of TiN effectively strengthen the physical and chemical double adsorption for polysulfides.As a result,the combination of TiN nanorod array and CC synergistic ally promotes sulfur utilization and electrochemical performances of S@TiN/CC cathode.A discharge capacity of1015.2 mAh·g^(-1)at 0.5C after 250 cycles and 604.1mAh·g^(-1)at 3C after 250 cycles is realized.Under a larger current density of 5C,the resulting S@TiN/CC cathode maintains a high discharge capacity of 666.6 mAh·g^(-1)and the Coulombic efficiency of about 100%.
