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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang zhi-Li Zuo han Guo Zi-Fei Xu Ying Zeng yun-Dong wu Xiao-jiang Hao Key Laboratory of Phytochemistry and Natural Medicines(Chinese Academy of Sciences) Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical OncogenomicsPeking University Shenzhen Graduate SchoolShenzhen 518055China Shenzhen Bay Laboratory Shenzhen 518055China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Microbial Metabolism School of Life Sciences&BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical UniversityGuiyang 550014China Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest ChinaKunming Institute of BotanyChinese Academy of SciencesKunming 650201China yunnan Key Laboratory for Wild Plant Resources Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical SciencesBeijing 100730China

In the intricate process of natural product biosynthesis,a metabolon can enhance metabolic flux by associating sequential enzymes.A fungal metabolon,comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G,is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide *** notoamide E as a substance,Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation,followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium ***,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol *** provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

Enrichment of Ni-Mo-V via pyrometallurgical reduction from spent hydrogenation catalysts and the multi-reaction mechanism

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Rare Metals 2023年第8期42卷 2700-2712页

作者： zhi-Sheng Shi yun-Ji Ding Xi-Ping Yin Bo Liu han-Lin Shen Bo-Yu wu Bao-Huai Zhao feng-lan han Christian Ekberg Shen-Gen Zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China Institute of Engineering Technology SINOPEC Catalyst Co.Ltd.Beijing 101111China School of Material Science and Engineering North Minzu UniversityYinchuan 750021China Nuclear Chemistry and Industrial Material Recycling Department of Chemistry and Chemical EngineeringChalmers University of TechnologyGothenburg 41296Sweden

Spent hydrogenation catalysts are important secondary resources due to richness in the valuable metals of Ni,Mo and *** of valuable metals from spent catalysts has high economic value and environmental benefits since they are hazardous wastes as *** recycling processes including hydrometallurgical leaching and soda roasting-leaching have disadvantages such as generating large amounts of wastewater,long process,and low recovery efficiency of valuable ***,this paper proposed synergistic enrichment of Ni,Mo and V via pyrometallurgical reduction at 1400-1500℃.The melting temperature and viscosity of slag were reduced through slag designing by software FactSage *** phase diagram of Al_(2)O_(3)-Cap-SiO_(2)-Na_(2)O-B_(2)O_(3)was drawn,and low-temperature region(≤1300℃)was selected as target slag ***,Mo,and V can be collaborative captured and recovered through the mutual solubility at molten *** the melting temperature and the amount of CaO,Na_(2)O and C were conducive to improving the metals recovery *** kilogram-scale experiments were carried out,and the recovery efficiencies of Ni,Mo and V were 98.3%,95.3%and 97.9%under optimized conditions:at 1500℃,with the basicity of 1.0,13.1 wt%SiO_(2),7.0 wt%B_(2)O_(3),7.7 wt%Na_(2)O and 20.0wt%*** distribution behavior of valuable metals was clarified by investigating the melting process of slag and the reduction in valuable *** was preferentially reduced and acted as a capturing agent,which captured other metals to form NiMoV alloys.

关键词： Spent hydrogenation catalysts(SHC) Pyrometallurgical reduction Slag design Enrichment Settlement

Integrated classification method of tight sandstone reservoir based on principal component analysise simulated annealing genetic algorithmefuzzy cluster means

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Petroleum Science 2023年第5期20卷 2747-2758页

作者： Bo-han wu Ran-Hong Xie Li-zhi Xiao jiang-feng Guo Guo-Wen Jin Jian-Wei Fu National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

In this research,an integrated classification method based on principal component analysis-simulated annealing genetic algorithm-fuzzy cluster means(PCA-SAGA-FCM)was proposed for the unsupervised classification of tight sandstone reservoirs which lack the prior information and core experiments.A variety of evaluation parameters were selected,including lithology characteristic parameters,poro-permeability quality characteristic parameters,engineering quality characteristic parameters,and pore structure characteristic *** PCA was used to reduce the dimension of the evaluation pa-rameters,and the low-dimensional data was used as *** unsupervised reservoir classification of tight sandstone reservoir was carried out by the SAGA-FCM,the characteristics of reservoir at different categories were analyzed and compared with the lithological *** analysis results of numerical simulation and actual logging data show that:1)compared with FCM algorithm,SAGA-FCM has stronger stability and higher accuracy;2)the proposed method can cluster the reservoir flexibly and effectively according to the degree of membership;3)the results of reservoir integrated classification match well with the lithologic profle,which demonstrates the reliability of the classification method.

关键词： Tight sandstone Integrated reservoir classification Principal component analysis Simulated annealing genetic algorithm Fuzzy cluster means

Co-cultured adventitious roots of Echinacea pallida and Echinacea purpurea inhibit lipopolysaccharide-induced inflammation via MAPK pathway in mouse peritoneal macrophages

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Chinese Herbal Medicines 2021年第2期13卷 228-234页

作者： Ming-zhi Fan Xiao-han wu Xue-feng Li Xuan-chun Piao Jun jiang Mei-lan Lian College of Agriculture Yanbian UniversityYanji 133002China

Objective:In order to elucidate the biological activity of the Co-cultured adventitious roots(ARs) of Echinacea pallida and Echinacea purpurea and provide theoretical basis for its application,and the antiinflammatory activities and potential mechanisms of Co-cultured ARs were ***:The experimental materials were obtained by bioreactor co-culture technology and used in the activity *** this study,mouse macrophages induced by lipopolysaccharide(LPS) were used as in vitro *** concentrations of AR extract(50-400 g/mL) were used to treat *** expression of pro-inflammatory cytokines was determined using enzyme linked immunosorbent *** inducible nitric oxide synthase and cyclooxygenase-2 expression,mitogen-activated protein kinase(MAPK) phosphorylation,and the inhibitor of nuclear factor-kappa B-a levels were determined by the Western blot ***:In the co-cultured ARs,total flavonoids and total caffeic acid were determined,and the contents of both bioactive compounds were significantly higher than those ARs from the single-species *** with the control group,the large amount of pro-inflammatory mediators was released after LPS ***,in the extract groups with different concentrations(25,50,and 100 g/mL),the production of these pro-inflammatory mediators was inhibited in a dose-dependent ***,the levels of phosphorylation of MAPK proteins,including p-p38, p-c-Jun N-terminal kinase,and p-extracellular regulated protein kinases were significantly(P <0.05) decreased in the extract groups,revealing that the AR extract probably involved in regulating the MAPK signaling ***:Collectively,our findings suggested that the co-cultured ARs of *** and *** can inhibit production of pro-inflammatory mediators in mouse peritoneal macrophages and possess the anti-inflammatory effect by regulating MAPK signaling pathways.

关键词： adventitious root anti-inflammation co-culture Echinacea pallida(Nutt.)Nutt Echinacea purpurea(L.) Moench mitogen-activated protein kinase

P2X7 receptor as the regulator of T-cell function in intestinal barrier disruption

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World Journal of Gastroenterology 2022年第36期28卷 5265-5279页

作者： zhi-feng jiang Wei wu han-Bing Hu Zheng-Yang Li Ming Zhong Lin Zhang Center of Emergency&Intensive Care Unit Jinshan Hospital of Fudan UniversityShanghai 201508China Department of Critical Care Medicine Zhongshan Hospital of Fudan UniversityShanghai 200032China Department of Gastroenterology Jinshan Hospital of Fudan UniversityShanghai 201508China

The intestinal mucosa is a highly compartmentalized structure that forms a directbarrier between the host intestine and the environment, and its dysfunction couldresult in a serious disease. As T cells, which are important components of themucosal immune system, interact with gut microbiota and maintain intestinalhomeostasis, they may be involved in the process of intestinal barrier dysfunction.P2X7 receptor (P2X7R), a member of the P2X receptors family, mediates the effectsof extracellular adenosine triphosphate and is expressed by most innate or adaptiveimmune cells, including T cells. Current evidence has demonstrated thatP2X7R is involved in inflammation and mediates the survival and differentiationof T lymphocytes, indicating its potential role in the regulation of T cell *** this review, we summarize the available research about the regulatory role andmechanism of P2X7R on the intestinal mucosa-derived T cells in the setting ofintestinal barrier dysfunction.

关键词： Intestinal barrier dysfunction P2X7 receptor T lymphocyte

Discovery of four gravitational lensing systems by clusters in the SDSS DR6

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Chinese Journal of Astronomy and Astrophysics 2009年第1期9卷 5-10页

作者： Zhong-Lue Wen Jin-Lin han Xiang-Yang Xu yun-Ying jiang zhi-Qing Guo Peng-Fei Wang feng-Shan Liu National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China College of Science Guizhou University Guiyang 550025 China College of Physics Science and Technology Shenyang Normal University Shenyang 110034 China

We report the discovery of 4 strong gravitational lensing systems by visual inspections of the Sloan Digital Sky Survey images of galaxy clusters in Data Release 6 （SDSS DR6）. Two of the four systems show Einstein rings while the others show tangen- tial giant arcs. These arcs or rings have large angular separations （〉 8″） from the bright central galaxies and show bluer color compared with the red cluster galaxies. In addition, we found 5 probable and 4 possible lenses by galaxy clusters.

关键词： galaxies clusters general -- gravitational lensing

Key factors controlling shale oil enrichment in saline lacustrine rift basin:implications from two shale oil wells in Dongpu Depression,Bohai Bay Basin

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Petroleum Science 2021年第3期18卷 687-711页

作者： Tao Hu Xiong-Qi Pang Fu-Jie jiang Qi-feng Wang Guan-yun wu Xiao-han Liu Shu jiang Chang-Rong Li Tian-wu Xu Yuan-Yuan Chen State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China College of Geosciences China University of PetroleumBeijing 102249China Energy&Geoscience Institute University of UtahSalt Lake CityUT 84108USA Research Institute of Exploration and Development Zhongyuan Oilfeld CompanySINOPECPuyangHenan 457001China

Comparative analyses of petroleum generation potential,reservoir volume,frackability,and oil mobility were conducted on 102 shale cores from the Dongpu *** show the shale has high organic matter contents composed of oil-prone type I and type II kerogens within the oil *** types of pores and fractures exist in the shale,with a porosity of up to 14.9%.The shale has high brittle mineral contents,extensive fractures,and high potential for oil mobility due to high seepage capacity and *** the petroleum generation potential of the shale at Well PS18-8 is relatively greater than that at Well PS18-1,oil content of the latter is greater due to the greater *** porosity and fracture density observed in Well PS18-1 are greater and more conducive to shale oil *** the shales in Wells PS18-1 and PS18-8 have similar brittle mineral contents,the former is more favorable for anthropogenic fracturing due to a higher preexisting fracture ***,the shale at Well PS18-1 has a higher seepage capacity and overpressure and therefore a higher oil *** fracture density and overpressure play key roles in shale oil enrichment.

关键词： Petroleum generation potential Reservoir volume Frackability Oil mobility Shale oil enrichment Dongpu Depression Saline lacustrine rift basin

Determining the effect of relative size of sensor on calibration accuracy of TEM cells

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Nuclear Science and Techniques 2019年第6期30卷 104-113页

作者： yun-Sheng jiang Cui Meng han-Bing Jin Ping wu zhi-Qian Xu Liu-Hong Huang Key Laboratory of Particle and Radiation Imaging Ministry of Education Beijing 100084 China Department of Engineering Physics Tsinghua University Beijing 100084 China

The time-domain calibration coefficient of a D-Dot sensor should be identical across various transverse electromagnetic (TEM) cells to comply with the IEEE Std 1309. However, in our previous calibration experiments, poor consistency was observed. The size of D-Dot sensors relative to TEM cells is considered the main reason for this poor consistency. Therefore, this study aims at determining the calibration coefficient of a D-Dot sensor. We calculate the theoretical coefficient as a reference. Practical calibration experiments involve the processing of TEM cells with three different sizes. To observe the response more clearly, corresponding models are constructed and numerical simulations are performed. The numerical simulations and experimental calibration are in good agreement. To determine the calibration accuracy, we quantify the accuracy using the relative error of the calibration coefficient. By comparing the coefficients obtained, it can be concluded that the perturbation error is about 15% when the relative size is over 1/3. Further, the relative size should be less than 1/5 to obtain a relative error below 10%.

关键词： D-Dot Electromagnetic sensor Time-domain calibration Accuracy Numerical simulation

Chemotherapy,transarterial chemoembolization,and nephrectomy combined treated one giant renal cell carcinoma(T3aN1M1)associated with Xp11.2/TFE3:A case report

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World Journal of Clinical Cases 2022年第28期10卷 10180-10185页

作者： Peng Wang Xiao Zhang Shuo-han Shao Fa wu Fei-Zhou Du Jun-feng Zhang zhi-Way Zuo Rui jiang Department of Radiology The General Hospital of Western Theater CommandChengdu 610083Sichuan ProvinceChina

BACKGROUND Renal cell carcinoma(RCC)with Xp11.2 translocation/TFE3 gene fusion is a rare and distinct subtype of RCC that is classified under tumors with translocation of the microphthalmia-associated transcriptional *** SUMMARY We report an adult case of Xp11.2 translocation advanced RCC with metastasis(T3a N1M1),after targeted treatment,alcohol ablation,and transarterial chemoembolization,who eventually underwent successful surgical *** recurrence or transfer was seen within one year,and the survival period was more than 3 years.A review of the relevant literature was conducted to improve our understanding of the pathogenesis,epidemiology,clinical manifestations,diagnosis,differential diagnosis,treatment,and other aspects of the *** Transarterial chemoembolization and ablation did not achieve the desired tumor reduction in this patient,but had a significant effect on reducing intraoperative bleeding and inhibiting tumor activity.

关键词： Xp11.2/TFE3 Renal Cell Carcinoma TACE Axitinib Zoledronic Acid Targeted therapy Multimodal imaging Case report