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人参二醇类皂苷的生物转化动态及人参稀有皂苷C-K或F2的制备

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高等学校化学学报 2019年第6期40卷 1184-1192页

作者：肖永坤刘春莹鱼红闪李泰厚徐龙权宋建国林完泽孙长凯金凤燮大连工业大学生物工程学院大连116034 韩国庆熙大学校韩方药生物技术学科韩国京畿道446-701 葵花药业集团(天津)药物研究院天津300457 大连大学生命科学与技术学院大连116622 韩国韩京国立大学校生物技术学科韩国京畿道456-749 大连理工大学生物医药工程学院大连116024

为了低成本有效制备人参稀有皂苷C-K或F2,将***.848菌酶用于转化含有人参皂苷(质量分数)分别为49.6%Rb1,25.9%Rd,19.3%Rc和5.23%Rb2的西洋参二醇混合皂苷.霉菌发酵时,采用人参二醇皂苷诱导物比人参提取液诱导物的产酶总活力提高10%~15%... 详细信息

为了低成本有效制备人参稀有皂苷C-K或F2,将***.848菌酶用于转化含有人参皂苷(质量分数)分别为49.6%Rb1,25.9%Rd,19.3%Rc和5.23%Rb2的西洋参二醇混合皂苷.霉菌发酵时,采用人参二醇皂苷诱导物比人参提取液诱导物的产酶总活力提高10%~15%.所产的2种诱导酶均能水解人参二醇皂苷的3-O-和20-O-多种糖基,均为人参皂苷酶Ⅰ型;但是人参二醇皂苷诱导物所产酶几乎全部转化人参二醇皂苷为C-K,而人参提取液诱导物所产酶则残留中间产物.使用黑曲霉人参二醇皂苷诱导所产酶,在转化西洋参二醇皂苷的动态研究中发现,酶反应1.5~2.5h,主要为产物F2;酶反应12h后,主要产物为C-K皂苷.基于此,40g人参二醇类皂苷在45℃粗酶反应24h,经处理得到含C-K质量分数为87%的23g酶反应产物,C-K转化率达85%(摩尔分数).用40g西洋参二醇皂苷在45℃粗酶反应2.5h,经处理得到含有质量分数为58%的F2和27%的C-K的26g酶反应产物,F2转化率为50.4%,C-K转化率为29.5%.通过人参二醇皂苷诱导的黑曲霉粗酶转化人参二醇类皂苷动态研究,建立了C-K转化率为85%,F2转化率为50%的制备方法,为大批量制备提供了基础依据.

关键词：人参二醇类皂苷人参皂苷生物转化人参皂苷F2 人参皂苷C-K 黑曲霉

TiO_(2)bunchy hierarchical structure with effective enhancement in sodium storage behaviors

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Carbon Energy 2022年第4期4卷 645-653页

作者： Shen Liu Kai Niu Shuailin Chen Xin sun Lehao Liu Bing Jiang Lihua Chu Xiaojun Lv Meicheng Li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China ElectricPower UniversityBeijingChina

Bronze phase TiO_(2)[TiO_(2)(B)]has great research potential for sodium storage since it has a higher theoretical capacity and ion mobility compar.d with other phases of TiO_(2).In this case,prepar.ng porous TiO_(2)(B)nanosheets,which can provide abundant sodium insertion channels,is the most effective way to improve transport ***,we use the strong one-dimensional TiO_(2)nanowires as the matrix for stringing these nanosheets together through a simple solvothermal method to build a bunchy hierarchical structure[TiO_(2)(B)-BH],which has fast pseudocapacitance behavior,high structural stability,and effective ion/electron *** the superiorities of this structure design,TiO_(2)(B)-BH has a higher capacity(131 vs.70 mAh g^(−1)[TiO_(2)-NWs]at 0.5 C).And it is worth mentioning that the reversible capacity of up to 500 cycles can still be maintained at 85 mAh g^(−1)at a high rate of 10 ***,we also further analyzed the sodium storage mechanism through the ex-situ X-ray powder diffraction test,which proved the high structural stability of TiO_(2)(B)-BH in the process of sodiumization/*** strategy of uniformly integrating nanosheets into a matrix can also be extended to prepar.ng electrode material structures of other energy devices.

关键词： hierarchical porous sodium-ion batteries TiO_(2) bronze phase nanosheets

Role of Matrix Metalloproteinase-1(MMP-1)/Protease-activated Receptor-1(par.1) Signaling Pathway in the Cervical Cancer Invasion

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Journal of Reproduction and Contraception 2014年第1期25卷 18-25页

作者： Ning-xia sun Qian ZHAO Chen YE Yan MA Wen LI Reproductive Center Changzheng Hospital the Second Military Medical University

Objective To investigate the role of matrix metalloproteinase-1 （MMP-1）/protease- activated receptor-1 （par.l） signaling in the cervical cancer invasion. Methods RT-PCR was used to test the mRNA level of MMP-1 in 59 cases of cervical squamous cell cancer. Cell invasion was evaluated by Transwell assay to explore the effect of adding human recombinant MMP-1 （rhMMP-1） and par.-siRNA on cervical cancer invasion. Results In cervical cancer tissues, more MMP-1 expression was observed than that in the normal cervical tissues, and its expression correlated with cancer status. Human recombinant MMP-1 （rhMMP-1） could promote Hela cell invasion, and its number of invasive cell correlated with the concentration of rhMMP-1. Disrupting the expression of par.1 reduced the MMP-1 promoting-effect on Hela cell invasion, but had no effect on non-MMP-1 invasive action. Conclusion The MMP-1/par.1 signaling pathway is involved in cervical cancer invasion. Therefore, blocking par.1 may represent a new therapeutic option for metastatic cervical cancer.

关键词： cervical cancer matrix metalloproteinase-1 (MMP-1) protease-activatedreceptor-1 (par.l) metastasis invasion

Linear Relationships between Photosynthetic Rate and Photochemical Energy Expressed by <i>par.lt;/i>×<i>Fv/Fm</i>

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American Journal of Plant Sciences 2018年第2期9卷 125-138页

作者： Dongbao sun Qingsuo Wang Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences Beijing China Key Laboratory of Dryland Agriculture Ministry of Agriculture Beijing China

Photosynthetic rate (Pn) of plants is simultaneously affected by photosynthetically active radiation (par. and maximum yield of primary photochemistry (Fv/Fm). In order to explore the quantitative relationship between Pn, par.and Fv/Fm, those par.meters were simultaneously measured for different plant species (maize, sunflower, daylily and alfalfa), growth stages and irrigation treatments. Results indicated that the diurnal variation of Pn had no significant correlation with that of Fv/Fm. Mean diurnal values of Pn were linearly correlated with those of Fv/Fm among the different irrigation treatments of alfalfa (p par.× Fv/Fm (p par.× Fv/Fm), the light energy directly used in photochemical reactions of plants.

关键词： Net Photosynthetic Rate par Fv/Fm Relationship

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AMAP评估报告解读:北极环境的汞

冰川冻土 2024年第5期46卷 1481-1493页

作者：杨争争孙世威苗希文张玉兰王兆清郭军明康世昌兰州大学资源环境学院西部环境教育部重点实验室甘肃兰州730000 中国科学院西北生态环境资源研究院冰冻圈科学与冻土工程重点实验室甘肃兰州730000 中国科学院大学资源与环境学院北京100049

北极监测与评估计划(AMAP)工作组于2021年发布了《北极环境的汞》科学评估报告,基于近年来北极环境介质中汞的观测和模拟研究,评估了北极环境介质的汞含量和储量水平,并预测了未来北极环境中汞含量的潜在变化。报告指出,全球大气汞排放... 详细信息

北极监测与评估计划(AMAP)工作组于2021年发布了《北极环境的汞》科学评估报告,基于近年来北极环境介质中汞的观测和模拟研究,评估了北极环境介质的汞含量和储量水平,并预测了未来北极环境中汞含量的潜在变化。报告指出,全球大气汞排放主要源于北极以外地区(>98%),部分大气汞可随大气环流远距离传输并沉降至北极生态系统,进而参与北极地区汞的生物地球化学循环。其中2/3的北极大气汞沉降至陆地环境,1/3沉降至海洋环境。陆地环境的汞主要储存于土壤、冰川和积雪中,这部分汞可在河流输运和海岸侵蚀作用下输入北冰洋。汞也可经洋流作用输入北冰洋。储存于北冰洋的汞又可经逃逸至大气、埋藏于大陆架和深海盆地及洋流流出而去除。北极环境的汞主要以无机形式赋存,部分可在厌氧环境中经微生物甲基化过程转化为甲基汞。相比气候变化,初级排放减少对未来北极环境汞含量变化的影响更大。因此,需实施严格且可行的全球人为汞减排政策,以期在未来20年降低北极环境汞含量。报告也指出,未来需更好地量化北极局地汞排放、加强汞的关键环境过程的研究和模型开发、研究携带汞甲基化和去甲基化基因的微生物群落、进行一致的初级排放和气候变化预测及编制全球人为汞排放清单等,以准确评估北极环境汞循环、预测北极环境汞含量变化。

关键词：北极汞减排气候变化 AMAP

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FePO4-coated Li[Li0.2Ni0.13Co0.13Mn0.54]O2 with improved cycling performance as cathode material for Li-ion batteries

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Rare Metals 2017年第11期36卷 899-904页

作者： Zhong Wang Hua-Quan Lu Yan-Ping Yin Xue-Yi sun Xiang-Tao Bai Xue-Ling Shen Wei-Dong Zhuang Shi-Gang Lu R&D Center for Vehicle and Energy Storage General Research Institute of Nonferrous Metals Beijing 100088 China China Automotive Battery Research Institue Co. Ltd Beijing 100088 China

Li[Li0.2Ni0.13Coo.13Mn0.54]O2 cathode materials were synthesized by carbonate-based co-precipitation method, and then, its surface was coated by thin layers of FePO4. The prepar.d samples were characterized by X-ray diffraction （XRD）, field emission scanning electron micro- scope （FESEM）, energy-dispersive spectroscopy （EDS）, and transmission electron microscopy （TEM）. The XRD and TEM results suggest that both the pristine and the coated materials have a hexagonal layered structure, and the FePO4 coating layer does not make any major change in the crystal structure. The FePO4-coated sample exhibits both improved initial discharge capacity and columbic efficiency compar.d to the pristine one. More significantly, the FePO4 coating layer has a much positive influence on the cycling perfor- mance. The FePO4-coated sample exhibits capacity reten- tion of 82 % after 100 cycles at 0.5℃ between 2.0 and 4.8 V, while only 28 % for the pristine one at the same charge-discharge condition. The electrochemical impe- dance spectroscopy （EIS） results indicate that this improved cycling performance could be ascribed to the presence of FePO4 on the surface of Li[Li0.2Ni0.13Co0.13Mno.54102 par. ticle, which helps to protect the cathode from chemical attacks by HF and thus suppresses the large increase in charge transfer resistance.

关键词： Cathodes Charge transfer Coated materials Coatings Crystal structure Electric batteries Electrochemical impedance spectroscopy Electrodes Energy dispersive spectroscopy Field emission cathodes High resolution transmission electron microscopy Lithium Lithium alloys Lithium compounds Manganese Nickel Precipitation (chemical) Scanning electron microscopy Secondary batteries Transmission electron microscopy X ray diffraction

燕山山地片麻岩风化过程与地球关键带结构耦合关系研究

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矿产勘查 2024年第8期15卷 1491-1499页

作者：孙紫坚陈自然卫晓锋王书来殷志强张守林周亦中色资源环境工程股份有限公司北京101304 北京矿产地质研究院有限责任公司北京100012 中色紫金地质勘查(北京)有限责任公司北京100012 中国地质调查局自然资源综合调查指挥中心北京100055

山地地球关键带的形成和演化在不同空间尺度上受风化过程的控制。本文以细粒角闪斜长片麻岩和粗粒黑云斜长片麻岩为例,研究片麻岩地球关键带结构的演化过程,识别影响地球关键带垂向结构的主控因素。结果表明片麻岩的物理风化程度较高,... 详细信息

山地地球关键带的形成和演化在不同空间尺度上受风化过程的控制。本文以细粒角闪斜长片麻岩和粗粒黑云斜长片麻岩为例,研究片麻岩地球关键带结构的演化过程,识别影响地球关键带垂向结构的主控因素。结果表明片麻岩的物理风化程度较高,化学风化程度低且细粒角闪斜长片麻岩化学风化程度相对较高,发育等体积风化,化学损耗低于0.5。在风化成土过程中黑云母含量和矿物粒径影响风化程度,从而影响其地球关键带结构,风化初始阶段黑云母通过铁氧化和层间钾被其他水合阳离子替代而扩张,岩石破碎,形成大量裂隙,渗透率提高。粗矿物颗粒导致母岩比表面积较低,物理崩解程度较高,促进孔隙度和渗透率提高,因此粗粒黑云斜长片麻岩风化前锋可达到5 m,强风化层可达1 m,土壤平均厚度多大于20 cm,而角闪斜长片麻岩风化前锋深度减至1.5 m以内,平均土壤厚度多小于20 cm。该研究成果有助于认识山区土壤形成过程,为国土空间规划提供科学依据。

关键词：燕山山地地球关键带岩石风化黑云母矿物颗粒

Review of soot measurement in hydrocarbon-air flames

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Science China(Technological Sciences) 2010年第8期53卷 2129-2141页

作者： LOU Chun,CHEN Chen,sun YiPeng&ZHOU HuaiChun State Key Laboratory of Coal Combustion,Huazhong University of Science and Technology,Wuhan 430074,China State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan China

Soot,which is produced in fuel-rich par.s of flames as a result of incomplete combustion of hydrocarbons,is the No.2 contributor to global warming after carbon *** soot measurement techniques is important to understand soot formation mechanism and control soot *** various soot measurement techniques,such as thermophoretic sampling par.ticles diagnostics followed by electron microscopy analysis,thermocouple par.icle densitometry,light extinction,laser-induced incandescence,two-color method,and emission computed tomography,are reviewed in this *** measurement principle and application cases of these measurement methods are described in *** development trend of soot measurement is to realize the on-line measurement of multi-dimensional distributions of temperature,soot volume fraction,soot par.icle size and other par.meters in hydrocarbon-air *** measurement techniques suitable for both small flames in laboratories and large-scale flames in industrial combustion devices should be ***,in some special situations,such as high-pressure,zero gravity and micro-gravity flames,soot measurement also should be provided.

关键词： hydrocarbon-air flames combustion measurement soot laser-induced incandescence emission CT

Proteinase-activated receptor 2 promotes tumor cell proliferation and metastasis by inducing epithelialmesenchymal transition and predicts poor prognosis in hepatocellular carcinoma

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World Journal of Gastroenterology 2018年第10期24卷 1120-1133页

作者： Liang sun Pi-Bao Li Yan-Fen Yao Ai-Yuan Xiu Zhi Peng Yu-Huan Bai Yan-Jing Gao Qilu Hospital of Shandong University Jinan 250012Shandong ProvinceChina Depar.ment of Critical Care Medicine Shandong Traffic HospitalJinan 250000Shandong provinceChina Depar.ment of Gastroenterology Qilu Hospital of Shandong UniversityJinan 250012Shandong provinceChina

AIM To clarify the role of proteinase-activated receptor 2(par.) in hepatocellular carcinoma, especially in the process of *** par. expression levels were assessed by qRT-PCR and immunohistochemistry(IHC) in patient tissues and in hepatocellular carcinoma cell lines SMMC-7721 and Hep G2. Cell proliferation and metastasis were assessed both in vitro and in vitro. Immunoblotting was carried out to monitor the levels of mitogen-activated protein kinase(MAPK) and epithelial-mesenchymal transition *** The prognosis was significantly poorer in patients with high par. levels than in those with low par. levels. Patients with high par. levels had advanced tumor stage(P = 0.001, chi-square test), larger tumor size(P = 0.032, chi-square test), and high microvascular invasion rate(P = 0.037, chi-square test). The proliferation and metastasis ability of SMMC-7721 and Hep G2 cells was increased after par. overexpression, while knockdown of par. decreased the proliferation and metastasis ability of SMMC-7721 and Hep G2 cells. Knockdown of par. also inhibited hepatocellular carcinoma tumor cell growth and liver metastasis in nude mice. Mechanistically, par. increased the proliferation ability of SMMC-7721 and Hep G2 cells via ERK activation. Activated ERK further promoted the epithelial-mesenchymal transition of these cells, which endowed them with enhanced migration and invasion ability. CONCLUSION These data suggest that par. plays an important role in the proliferation and metastasis of hepatocellular carcinoma. Therefore, targeting par. may present a favorable target for treatment of this malignancy.

关键词： Hepatocellular carcinoma Proteinaseactivated receptor 2 Epithelial-mesenchymal transition