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Mechanism of action of the bile acid receptor TGR5 in obesity

Acta Pharmaceutica Sinica B 2024年第2期14卷 468-491页

作者： Weijun Lun Qihao Yan Xinghua guo Minchuan Zhou Yan Bai Jincan He Hua Cao Qishi Che jiao guo Zhengquan Su Guangdong Engineering Research Center of Natural Products and New Drugs Guangdong Provincial University Engineering Technology Research Center of Natural Products and DrugsGuangdong Pharmaceutical UniversityGuangzhou 510006China Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine Key Laboratory of Glucolipid Metabolic DisorderMinistry of Education of ChinaGuangdong TCM Key Laboratory for Metabolic DiseasesGuangdong Pharmaceutical UniversityGuangzhou 510006China School of Public Health Guangdong Pharmaceutical UniversityGuangzhou 510310China School of Chemistry and Chemical Engineering Guangdong Pharmaceutical UniversityZhongshan 528458China Guangzhou Rainhome Pharm&Tech Co. Ltd.Science CityGuangzhou 510663China

G protein-coupled receptors(GPCRs)are a large family of membrane protein receptors,and Takeda G protein-coupled receptor 5(TGR5)is a member of this family.As a membrane receptor,TGR5 is widely distributed in different parts of the human body and plays a vital role in regulating metabolism,including the processes of energy consumption,weight loss and blood glucose homeostasis.Recent studies have shown that TGR5 plays an important role in glucose and lipid metabolism disorders such as fatty liver,obesity and diabetes.With the global obesity situation becoming more and more serious,a comprehensive explanation of the mechanism of TGR5 and filling the gaps in knowledge concerning clinical ligand drugs are urgently needed.In this review,we mainly explain the anti-obesity mechanism of TGR5 to promote the further study of this target,and show the electron microscope structure of TGR5 and review recent studies on TGR5 ligands to illustrate the specific binding between TGR5 receptor binding sites and ligands,which can effectively provide new ideas for ligand research and promote drug research.

关键词： Obesity TGR5 Bile acids Ligand Appetite Metabolism GLP-1 Inflammation

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Comparative analysis of frictional behavior and mechanism of molybdenum ditelluride with different structures

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Friction 2024年第1期12卷 110-119页

作者： Lina ZHANG Xinfeng TAN Jianguo jiao Dan guo Jianbin LUO State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

Two-dimensional(2D)transition metal dichalcogenides(TMDCs)have layered structures with excellent tribological properties.Since the energy difference between hexagonal-molybdenum ditelluride(2H-MoTe_(2))and distorted octahedral-molybdenum ditelluride(1T′-MoTe_(2))is very small among the transition metal dichalcogenides(TMDCs),MoTe_(2) becomes one of the most promising candidates for phase engineering.In our experiment,we found that the friction force and friction coefficient(COF)of 2H-MoTe_(2) were an order of magnitude smaller than those of 1T′-MoTe_(2) by the atomic force microscope(AFM)experiments.The friction difference between 1T′-MoTe_(2) and 2H-MoTe_(2) was further verified in molecular dynamics(MD)simulations.The density functional theory(DFT)calculations suggest that the friction contrast is related to the difference in sliding energy barrier of the potential energy surface(PES)for a tip sliding across the surface.The PES obtained from the DFT calculation indicates that the maximum energy barrier and the minimum energy path(MEP)energy barrier of 2H-MoTe_(2) are both smaller than those of 1T′-MoTe_(2),which means that less energy needs to be dissipated during the sliding process.The difference in energy barrier of the PES could be ascribed to its larger interlayer spacing and weaker Mo–Te interatomic interactions within the layers of 2H-MoTe_(2) than those of 1T′-MoTe_(2).The obvious friction difference between 1T′-MoTe_(2) and 2H-MoTe_(2) not only provides a new non-destructive means to detect the phase transition by the AFM,but also provides a possibility to tune friction by controlling the phase transition,which has the potential to be applied in extreme environments such as space lubrication.

关键词： friction two-dimensional(2D)materials distorted octahedral-molybdenum ditelluride(1T′-MoTe_(2)) hexagonal-molybdenum ditelluride(2H-MoTe_(2)) phase transition

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Day-ahead Voltage-stability-constrained Network Topology Optimization with Uncertainties

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 730-741页

作者： Dingli guo Lei Wang Ticao jiao Ke Wu Wenjing Yang the School of Electrical and Electronic Engineering Shandong University of Technology

A day-ahead voltage-stability-constrained network topology optimization(DVNTO) problem is proposed to find the day-ahead topology schemes with the minimum number of operations(including line switching and bus-bar splitting) while ensuring the sufficient hourly voltage stability margin and the engineering operation requirement of power systems. The AC continuation power flow and the uncertainty from both renewable energy sources and loads are incorporated into the formulation. The proposed DVNTO problem is a stochastic, largescale, nonlinear integer programming problem. To solve it tractably, a tailored three-stage solution methodology, including a scenario generation and reduction stage, a dynamic period partition stage, and a topology identification stage, is presented. First, to address the challenges posed by uncertainties, a novel problem-specified scenario reduction process is proposed to obtain the representative scenarios. Then, to obtain the minimum number of necessary operations to alter the network topologies for the next 24-hour horizon, a dynamic period partition strategy is presented to partition the hours into several periods according to the hourly voltage information based on the voltage stability problem. Finally, a topology identification stage is performed to identify the final network topology scheme. The effectiveness and robustness of the proposed three-stage solution methodology under different loading conditions and the effectiveness of the proposed partition strategy are evaluated on the IEEE 118-bus and 3120-bus power systems.

关键词： Power system stability Switches Uncertainty Stability criteria Network topology Topology Renewable energy sources

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Machine learning predicts atomistic structures of multielement solid surfaces for heterogeneous catalysts in variable environments

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The Innovation 2024年第2期5卷 79-87页

作者： Huan Ma Yueyue jiao Wenping guo Xingchen Liu Yongwang Li Xiaodong Wen State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China University of Chinese Academy of Sciences Beijing 100049China National Energy Center for Coal to Liquids Synfuels China Co.Ltd.Beijing 101400China Beijing Advanced Innovation Center for Materials Genome Engineering IndustryUniversity Cooperation Base between Beijing Information S&T University and Synfuels China Co.Ltd.Beijing 100101China

Solid surfaces usually reach thermodynamic equilibrium through particle exchange with their environment under reactive conditions.A prerequisite for understanding their functionalities is detailed knowledge of the surface composition and atomistic geometry under working conditions.Owing to the large number of possible Miller indices and terminations involved in multielement solids,extensive sampling of the compositional and conformational space needed for reliable surface energy estimation is beyond the scope of ab initio calculations.Here,we demonstrate,using the case of iron carbides in environments with varied carbon chemical potentials,that the stable surface composition and geometry of multielement solids under reactive conditions,which involve large compositional and conformational spaces,can be predicted at ab initio accuracy using an approach that combines the bond valence model,Gaussian process regression,and ab initio thermodynamics.Determining the atomistic structure of surfaces under working conditions paves the way toward identifying the true active sites of multielement catalysts in heterogeneous catalysis.

关键词： surfaces solids environments

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Highly effective self-assembled porphyrin MOCs nanomaterials for enhanced photodynamic therapy in tumor

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Chinese Chemical Letters 2024年第5期35卷 302-306页

作者： Yihao Zhang Yang jiao Xianchao Jia Qiaojia guo Chunying Duan School of Chemistry Dalian University of TechnologyDalian 116024China State Key Laboratory of Fine Chemicals School of ChemistryDalian University of TechnologyDalian 116024China

Porphyrins and their derivatives are excellent photosensitizers in photodynamic therapy(PDT).The modification of porphyrin molecules into metal-organic cages(MOCs)is a viable strategy to improve their bioavailability.In this work,MOC C66 based on porphyrin was synthesised by a one-pot self-assembly method.The three-dimensional structure of the metal-organic cage ameliorated the aggregation and selfquenching of porphyrins and increased the molar absorption coefficient in the visible light region,which enhanced the reactive oxygen species(ROS)yield of porphyrins and effectively improved the efficiency of photodynamic therapy.ROS generation ability tests in solution confirmed the improved reactive oxygen capacity of the cage,which showed greater phototoxicity to HeLa and MCF-7 cells in vitro,suggesting a new strategy for future modifications of the simple synthesis of porphyrins as photosensitizers.

关键词： Metal-organic cage Porphyrin Photodynamic therapy Reactive oxygen species Nanoparticles

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Insight study of rare earth elements in PM_(2.5)during five years in a Chinese inland city:Composition

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Journal of Environmental Sciences 2024年第4期138卷 439-449页

作者： Yi-Wen Shen Chang-Xian Zhao Hao Zhao Shuo-Fei Dong Qi guo jiao-jiao Xie Mei-Ling Lv Chun-Gang Yuan Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department ofEnvironmental Science&EngineeringNorth China Electric Power UniversityBaoding 071000China MOE Key Laboratory of Resources and Environmental Systems Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China Agilent Technologies Co.Ltd.(China) Beijing 100102China

The booming development of rare earth industry and the extensive utilization of its products accompanied by urban development have led to the accelerated accumulation of rare earth elements(REEs)as emerging pollutants in atmospheric environment.In this study,the variation of REEs in PM_(2.5)with urban(a non-mining city)transformation was investigated through five consecutive years of sample collection.The compositional variability and provenance contribution of REEs in PM_(2.5)were characterized,and the REEs exposure risks of children and adults via inhalation,ingestion and dermal absorption were also evaluated.The results showed an increase in the total REEs concentration from 46.46±35.16 mg/kg(2017)to 81.22±38.98 mg/kg(2021)over the five-year period,with Ce and La making the largest contribution.The actual increment of industrial and traffic emission source among the three pollution sources was 1.34 ng/m^(3).Coal combustion source displayed a downward trend.Ingestion was the main exposure pathway for REEs in PM_(2.5)for both children and adults.Ce contributed the most to the total intake of REEs in PM_(2.5)among the population,followed by La and Nd.The exposure risks of REEs in PM_(2.5)in the region were relatively low,but the trend of change was of great concern.It was strongly recommended to strengthen the concern about traffic-related non-exhaust emissions of particulate matter.

关键词： Rare earth elements Exposure risks Pollution sources Traffic-related non-exhaust emissions

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Highly selective and eco-friendly dihydroisoquinoline synthesis via Cu/Co synergistic catalysis in Cu NPs@MOFs catalyst under mild conditions

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Science China Chemistry 2024年第5期67卷 1561-1568页

作者： Peng-Fei guo Ze-Long Liang Yue-E jiao Hang Xu Bin Zhao Key Laboratory of Advanced Energy Material Chemistry Renewable Energy Conversion and Storage CenterDepartment of ChemistryNankai UniversityTianjin 300071China

3,4-Dihydroisoquinoline(DHIQ)is an important precursor used in the production of drugs for treating cancer,HIV,Alzheimer's disease,etc.Major studies on DHIQ synthesis show low catalytic selectivity due to the susceptible over-oxidation feedstock of1,2,3,4-tetrahydroisoquinoline(THIQ),which often requires alkali co-catalysts.Therefore,it is desirable yet challenging to explore a highly selective and efficient oxydehydrogenation capacity for DHIQ synthesis under eco-friendly reaction conditions.Herein,a novel framework 1 was synthesized,exhibiting 1D channels with the size of 4.6 A×9.6 A and high solvent/p H/thermal stability.A stable framework allows it to encapsulate Cu nanoparticles(NPs)to form Cu NPs@1-x(x=1,2,3,and 4)with varying loading amounts of Cu NPs at 2.0 wt%,3.0 wt%,4.0 wt%,and 6.0 wt%,respectively.Cu NPs@1-3 could selectively catalyze the reaction from THIQ to DHIQ with a high selectivity of 98%and a recorded turnover frequency(TOF)of 22.1 h-1under eco-friendly mild conditions.The corresponding catalytic activity can maintain at least five recyclings and can be further applied to gram-scale experiments.Additionally,the efficient preparation of DHIQ catalyzed by Cu NPs@1-3 could be realized even under air conditions.Importantly,the anticancer molecule precursor synthesis of 6,7-dimethoxy-3,4-dihydroisoquinoline was also selectively catalyzed by Cu NPs@1-3.Mechanism investigations revealed that high catalytic performance can be attributed to the stable framework and the synergistic catalytic effect of the loaded Cu NPs and Co metal centers.More importantly,this work represents the first example of MOF catalysts for selectively thermo-catalytic DHIQ synthesis and demonstrates a simple approach to obtain efficient catalysts for selective oxydehydrogenation in the production of unsaturated compounds.

关键词： metal-organic frameworks Cu NPs@MOFs 3 4-dihydroisoquinoline selective oxydehydrogenation synergistic catalysis

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Runoff change in the Yellow River Basin of China from 1960 to 2020 and its driving factors

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Journal of Arid Land 2024年第2期16卷 168-194页

作者： WANG Baoliang WANG Hongxiang jiao Xuyang HUANG Lintong CHEN Hao guo Wenxian School of Water Conservancy North China University of Water Resources and Electric PowerZhengzhou 450046China College of Water Resources North China University of Water Resources and Electric PowerZhengzhou 450046China

Analysing runoff changes and how these are affected by climate change and human activities is deemed crucial to elucidate the ecological and hydrological response mechanisms of rivers.The Indicators of Hydrologic Alteration and the Range of Variability Approach(IHA-RVA)method,as well as the ecological indicator method,were employed to quantitatively assess the degree of hydrologic change and ecological response processes in the Yellow River Basin from 1960 to 2020.Using Budyko's water heat coupling balance theory,the relative contributions of various driving factors(such as precipitation,potential evapotranspiration,and underlying surface)to runoff changes in the Yellow River Basin were quantitatively evaluated.The results show that the annual average runoff and precipitation in the Yellow River Basin had a downwards trend,whereas the potential evapotranspiration exhibited an upwards trend from 1960 to 2020.In approximately 1985,it was reported that the hydrological regime of the main stream underwent an abrupt change.The degree of hydrological change was observed to gradually increase from upstream to downstream,with a range of 34.00%-54.00%,all of which are moderate changes.However,significant differences have been noted among different ecological indicators,with a fluctuation index of 90.00%at the outlet of downstream hydrological stations,reaching a high level of change.After the mutation,the biodiversity index of flow in the middle and lower reaches of the Yellow River was generally lower than that in the base period.The research results also indicate that the driving factor for runoff changes in the upper reach of the Yellow River Basin is mainly precipitation,with a contribution rate of 39.31%-54.70%.Moreover,the driving factor for runoff changes in the middle and lower reaches is mainly human activities,having a contribution rate of 63.70%-84.37%.These results can serve as a basis to strengthen the protection and restoration efforts in the Yellow River Basin and further promote the rational development an

关键词： Budyko theory hydrological regime attribution analysis ecological responses Yellow River climate change human activity runoff

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Human activity over natural inputs determines the bacterial community in an ice core from the Muztag ata glacier

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Science China Earth Sciences 2024年第5期67卷 1489-1499页

作者： Yongqin LIU Nianzhi jiao Mukan JI Keshao LIU Baiqing XU Bixi guo Tandong YAO State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Center for Pan-third Pole Environment Lanzhou UniversityLanzhou 730013China University of Chinese Academy of Sciences Beijing 100101China State Key Laboratory for Marine Environmental Science Xiamen UniversityXiamen 361102China

Ice core provides a valuable vertical timeline of past climates and anthropogenic activities.Environmental proxies have been widely used in these studies,but there are few biological indicators available.To address this gap,we investigated the bacterial community from a 74 m ice core of Muztag ata glacier on the Tibetan Plateau to link biological indicators with past climate and anthropogenic activities.By analyzing the portion of the ice core with environmental proxies available(corresponding to 1907 to 1991),we observed an increase in bacterial richness throughout the ice core,which was associated with higher NH_(4)^(+),an indicator of agricultural development.The bacterial community was jointly determined by human activity,natural input,and air temperature,with a strong human influence after the 1950s.Furthermore,the relative abundance of animal gut-associated bacteria,including Aerococcaceae,Nocardiaceae,Muribaculaceae,and Lachnospiraceae,was associated with livestock number changes in the Central Asian region.Together with other bacterial lineages,they jointly explained 59.8%of the livestock number changes.This study provides quantitative evidence of the associations between bacterial indicators and past climate and human activities,highlighting the potential of using bacterial proxies for ice core studies.

关键词： Ice core of Muztag ata glacier Climate change and anthropogenic activity Biological indicator Gut-associated bacteria livestock number in the Central Asian region

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Rhodium-catalyzed Doyle-Kirmse rearrangement reactions of sulfoxoniun ylides

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Chinese Chemical Letters 2024年第4期35卷 363-366页

作者： Ying-Di Hao Zhi-Qian Lin Xiao-Yu guo jiao Liang Can-Kun Luo Qian-Tao Wang Li guo Yong Wu Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Department of Medicinal Chemistry Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China

Doyle-Kirmse rearrangement reactions have received continuous attention as an important method for constructing complex chemical structures. Herein, we disclosed an efficient rhodium-catalyzed DoyleKirmse rearrangement reaction, which can simultaneously construct C–C bonds and C–X(X = S/Se) bonds using sulfoxonium ylides as starting materials to obtain sulfur-or selenium-containing compounds. This strategy is characterized by the safer and greener carbene precursor, high yields and broad substrate scope, possessing a wide range of application.

关键词： Sulfoxonium ylides Rhodium(Ⅱ)-catalyzed Carbene Rearrangement reactions One-pot process

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