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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 Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

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 B. Using 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 unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This 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

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Multicomponent polymerization of elemental sulfur,difluoromethylene phosphobetaine and aryl silyl ethers toward aromatic poly(O,O′-monothiocarbonate)s

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Science China Chemistry 2025年

作者： Yongjiang Yu Rongrong Hu Ben Zhong tang State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates South China University of Technology School of Science and Engineering Shenzhen Institute of Aggregate Science and Technology The Chinese University of Hong Kong aiE Institute

Polythiocarbonates with similar structures to polycarbonates, have emerged as a group of promising sulfur-containing polymers with a range of practical applications, taking advantages of their excellent optical properties, good thermal stability and filmforming ability, and so on. However, the synthesis of polythiocarbonates generally suffered from mixed isomeric structures of repeating units, and hazardous sulfur-containing reagents. In this work, an efficient multicomponent reaction of elemental sulfur,difluoromethylene phosphobetaine（PDFA）, and aryl silyl ethers was designed with the assistance of organic base 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene（MTBD） to produce 12 kinds of O,O′-monothiocarbonate compounds in up to 93% yields,taking advantages of the unique chemical property of difluorocarbene, and the deprotection of silyl group by F-generated from PDFA. Most importantly, the MTBD-assisted multicomponent polymerization of bis（aryl silyl ether）s, elemental sulfur, and PDFA was developed, affording 12 kinds of poly（O,O′-monothiocarbonate）s with well-defined structures, high Mws of up to16900 g/mol and high yields（up to 99%）. These poly（O,O′-monothiocarbonate）s possessed good film-forming properties and thermal stability, high light refractive indices and transmittance. The facile synthesis of these polymonothiocarbonates might pave the way for the development of promising sulfur-containing polymer materials.

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Recognizing parallel-stranded g-quadruplex by cyanine dye dimer based on dual-site binding mode

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Chinese Chemical Letters 2015年第6期26卷 705-708页

作者： li-Jia Yu Wei gai Qian-Fan Yang Jun-Feng Xiang Hong-Xia Sun Qian li li-Xia Wang ai-Jiao guan Ya-lin tang Beijing National Laboratory for Molecular Science Center for Molecular ScienceState Key Laboratory for Structural Chemistry for Unstable and State SpeciesInstitute of ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences

g-quadruplexes （g4s） play important roles in biological systems, such as telomere maintenance, replication, and transcription. Based on the DNA sequence, loop geometry, and the local environments, g4s can be classified into different conformations. It is important to detect different types of g4s to monitor the diseases related with g4s. Most ligands bind to g4s based on end-stacking modes, while rare ligands bind to g4s through groove binding modes. We have found that a cyanine dye DMSB interacts with parallel g4 by end-stacking and groove simultaneous binding mode. In this article, we found that DMSB could simply discriminate parallel g4s from other DNA motifs by using UV-vis spectrum. These results give some clues to develop high specificity g4 probes.

关键词： Parallel-stranded g-quadruplex Cyanine dye Dual-site binding modec-myc

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Unraveling the mechanism of action of Shangxia liangji formula for treating insomnia:a metabolomics and network pharmacology approach

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Traditional Medicine Research 2025年第2期10卷 16-29页

作者： Xia-Jie Quan Hao liang Yong-Hong tang li Jiang Xiong-Ying Ji Feng-Ying Zhang Ping Zhang Bo Ouyang Department of Information The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China Department of Neurology The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China Department of gastroscopy The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China Department of Traditional Chinese Medicine The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China

Background:Insomnia is a prevalent clinical condition and Shangxia liangji formula(SXLJF)is a well-established method of ***,the specific mechanism of action of SXLJF remains ***:The mouse model of insomnia was established by intraperitoneal injection of ***-two mice were randomly divided into a negative control group,model group,SXLJF group(18.72 g/kg/day),and positive control group(diazepam,2 mg/kg)and treated with the corresponding drugs for 7 consecutive *** open field test and pentobarbital-induced sleeping test were ***-MS-based untargeted metabolomics and network pharmacology were applied to explore the potential targets of SXLJF for treating ***,key targets were validated using ***:Behavioral tests demonstrated that SXLJF reduced the total distance,average velocity,central distance,and sleep latency,and prolonged sleep *** and network pharmacology revealed potential targets,signaling pathways,metabolic pathways,and metabolites associated with the anti-insomnia effects of ***,tyrosine hydroxylase(TH)and tyrosine metabolism emerged as crucial metabolic pathways and targets,***-qPCR results supported the role of TH in the mechanism of SXLJF in treating ***:In conclusion,TH and tyrosine metabolism may represent significant targets and pathways for SXLJF in treating insomnia.

关键词： Shangxia liangji formula insomnia metabolomics network pharmacology tyrosine hydroxylase tyrosine metabolism

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Modeling ε Eri and Asteroseismic Tests of Element Diffusion

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Chinese Journal of Astronomy and Astrophysics 2008年第5期8卷 591-602页

作者： Ning gai Shao-Lan Bi Yan-Ke tang National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Department of Astronomy Beijing Normal University Beijing 100875 China graduate School of Chinese Academy of Sciences Beijing 100049 China

Taking into account the helium and metal diffusion, we explore the possible evolutionary status with a seismic analysis, of the MOST （Microvariability and Oscillations of STars） target： the star e Eri. We adopt different input parameters to construct models to fit the available observational constraints in, e.g., Teff, L, R and [Fe/H]. From the computation we obtain the average large spacings of e Eri to be about 194 ± 1μHz. The age of the diffused models was found to be about 1 gyr, which is younger than the age determined previously by models without diffusion. We found that the effect of pure helium diffusion on the internal structure of the young low-mass star is slight, but that of metal diffusion is obvious. The metal diffusion leads the models to have much higher temperature in the radiative interior, and, correspondingly a higher sound speed there, hence a larger frequency and spacings.

关键词： stars evolution - stars interiors -stars individual ∈ Eridani

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Clinical observation of white eye distribution in patients with hyperlipidemia: an artificial intelligence digital visual examination technique

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Journal of Traditional Chinese Medicine 2025年

作者： SONg Tianli li Haixia liU li'an Department of Cardiology， the guang'anmen Hospital， China Academy of Chinese Medical Sciences National College， Beijing University of Chinese Medicine

Objective: To explore the clinical observation of white eye distribution characteristics of hyperlipidemic patients based on artificial intelligence digital eye diagnosis technology. Methods: One hundred and fifty subjects were examined in the outpatient and inpatient departments of guang'anmen Hospital of the China Academy of Traditional Chinese Medicine from 01 February 2022 to 01 February 2023， including 80 cases in the hyperlipidemic patient (HLP) group and 70 cases in the normal lipid level patient (NC) group. The two groups were collected and extracted by the artificial intelligence visual diagnostic instrument and analyzed by the MyEyeD-10 white eye shadowless imaging health intelligence analysis system. Finally， SPSS 26.0 (Version X; IBM Corp.， Armonk， NY， USA) was used for statistical processing. Results: Significant differences were noted in the scores of "spot" and "foggy" features between the two groups. Between groups， the "spot" feature score of the white eye morphology in the HLP group (11.07 ± 3.22) was higher than that in the NC group (7.50 ± 4.11) (P ggy" feature score of the eye morphology in the HLP group (8.37 ± 2.25) was higher than that in the NC group (P gher than that of the NC group (5.72 ± 1.21) (P gnificant differences in the "A" (stomach)， "B"， "O" (spleen)， and "M" (liver) eye-contact region scores between the two groups， and the "B"， "O" (spleen) and "M" (liver) eye-contact region scores were significantly different. The scores of the white eye channel region in the HLP group were significantly higher than those in the control group， with the "A"， "B"， and "O" regions (P gion (P gion (P gnificantly different， and the scores of "dull red" and "yellow" colors of the white eye choroid in the HLP group were significantly higher than those in the HLP g

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P2X7 receptor activation aggravates NADPH oxidase 2-induced oxidative stress after intracerebral hemorrhage

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Neural Regeneration Research 2021年第8期16卷 1582-1591页

作者： Hong Deng Ye Zhang gai-gai li Hai-Han Yu Shuang Bai guang-Yu guo Wen-liang guo Yang Ma Jia-Hui Wang Na liu Chao Pan Zhou-Ping tang Department of Neurology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Endocrinology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Oxidative stress is a crucial pathological process that contributes to secondary injury following intracerebral hemorrhage. P2X7 receptor(P2X7R), which is activated by the abnormal accumulation of extracellular ATP, plays an important role in the regulation of oxidative stress in the central nervous system, although the effects of activated P2X7R-associated oxidative stress after intracerebral hemorrhage remain unclear. Mouse models of intracerebral hemorrhage were established through the stereotactic injection of 0.075 U VII collagenase into the right basal ganglia. The results revealed that P2X7R expression peaked 24 hours after intracerebral hemorrhage, and P2X7R expressed primarily in neurons. The inhibition of P2X7R, using A438079(100 mg/kg, intraperitoneal), reduced nicotinamide adenine dinucleotide phosphate oxidase 2(NOX2) expression and malondialdehyde generation, increased superoxide dismutase and glutathione/oxidized glutathione levels, and alleviated neurological damage, brain edema, and apoptosis after intracellular hemorrhage. The P2X7R inhibitor A438079(100 mg/kg, intraperitoneal injection) inhibited the activation of extracellular signal-regulated kinase 1/2(ERK1/2) and nuclear factor kappa-B(NF-κB) after intracerebral hemorrhage. Blocking ERK1/2 activation, using the ERK1/2 inhibitor U0126(2 μg, intraventricular injection), reduced the level of NOX2-mediated oxidative stress induced by P2X7R activation after intracellular hemorrhage. Similarly, the inhibition of NF-κB, using the NF-κB inhibitor JSH-23(3.5 μg, intraventricular), reduced the level of NOX2-mediated oxidative stress induced by P2X7R activation. Finally, gSK2795039(100 mg/kg, intraperitoneal), a NOX2 antagonist, attenuated P2X7R-mediated oxidative stress, neurological damage, and brain edema after intracerebral hemorrhage. The results indicated that P2X7R activation aggravated NOX2-induced oxidative stress through the activation of the ERK1/2 and NF-κB pathways following intracerebral he

关键词： brain central nervous system factor inflammation injury pathways repair stroke

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有Bernoulli中断休假和随机启动时间的N-策略多重休假M=g=1排队的队长分析

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应用数学 2025年第1期38卷 276-293页

作者：李茜唐应辉余玅妙魏瑛源四川师范大学数学科学学院四川成都610068 河西学院数学与统计学院甘肃张掖734000

本文研究一个有Bernoulli中断休假和随机启动时间的N-策略多重休假M/g/1排队模型,其中Bernoulli中断休假是指:如果在休假中有顾客到达,服务员以概率p(0≤p≤1)立即中断休假回到系统中并启动服务设施,以概率(1−p)不中断休假直到此次休假... 详细信息

本文研究一个有Bernoulli中断休假和随机启动时间的N-策略多重休假M/g/1排队模型,其中Bernoulli中断休假是指:如果在休假中有顾客到达,服务员以概率p(0≤p≤1)立即中断休假回到系统中并启动服务设施,以概率(1−p)不中断休假直到此次休假结束后才回到系统启动服务设施.当系统的启动完成后,若系统中顾客数大于等于事先设置的阈值N(≥1),则服务员开始为顾客服务直到系统再次变空.运用全概率分解技术和更新过程理论讨论了系统在时刻t队长的瞬态概率分布,得到了队长瞬态概率分布的拉普拉斯变换表达式.在瞬态分析的基础上,使用洛必达法则和一些代数运算推导出了队长稳态概率分布的递推表达式,以及其它一些排队指标,如队长稳态概率分布的母函数、平均队长和附加队长的概率分布等.最后,讨论了一些特殊情形.

关键词： Bernoulli中断休假随机启动时间 N-策略全概率分解队长分布

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Minimizing makespan of a production batch within concurrent systems:Seru production perspective

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Journal of Management Science and Engineering 2022年第1期7卷 1-18页

作者： Yin gai Yong Yin Jiafu tang Shiqiang liu College of Management Science and Engineering Dongbei University of Finance and EconomicsDalian116025China graduate School of Business Doshisha UniversityKyoto602-8580Japan School of Economics and Management Fuzhou UniversityFuzhou350108China

This paper discusses the makespan minimization of a production batch within a specific concurrent system,seru production system.A seru production system consists of multiple independent serus.A seru is a compact assembly origination in which products are assembled from-the-beginning-to-the-end without *** capability of a seru production system is its responsiveness.A performance measure used to evaluate a seru system’s responsiveness is the makespan of production batches assembled within the seru *** study addresses the makespan minimization problem through an optimal seru loading *** problem is formulated as a min-max integer optimization *** exact dimension-reduction Algorithm is developed to obtain the optimal allocation that minimizes the *** show that the solution space increases very *** contrast,our algorithm is efficient with a polynomial computational complexity of,where is the total number of serus in a seru *** verify the usefulness of the developed exact dimension-reduction algorithm,we compare it with a widely practiced greedy algorithm through *** find that our optimal algorithm is robust in most cases and the greedy algorithm is efficient when variability in production efficiencies is *** result can guide us to adopt different algorithms in different business *** the variability in production efficiencies is high,e.g.,new employees and/or new products assembly,the greedy algorithm is *** other cases,our optimal algorithm should be adopted to obtain the minimum *** also extend the method to the application of a rotating seru.

关键词： Assembly greedy algorithm Dimension reduction Exact algorithm Variability Polynomial computational complexity

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Identification and fine mapping of a fertility restorer gene for wild abortive cytoplasmic male sterility in the elite indica rice non-restorer line 9311

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The Crop Journal 2023年第3期11卷 887-894页

作者： Zuopeng Xu Yuanyue Du Xixu li Ruixuan Wang Zhi'ai Chen Xiangqiang Zhao Qiaoquan liu Shuzhu tang Honggen Zhang Jiangsu Key Laboratory of Crop genetics and Physiology/Key Laboratory of Plant Functional genomics of the Ministry of Education/Jiangsu Key Laboratory of Crop genomics and Molecular Breeding Agricultural CollegeYangzhou UniversityYangzhou 225009JiangsuChina Jiangsu Co-Innovation Center for Modern Production Technology of grain Crops Yangzhou UniversityYangzhou 225009JiangsuChina School of life Sciences Nantong UniversityNantong 226019JiangsuChina

The wild abortive(WA)-type cytoplasmic male sterility(CMS)derived from the wild rice species Oryza rufipogon *** used widely in three-line indica *** identification and mapping of restorer of fertility(Rf)genes aided in the development of WA-type *** we report that testcross F1 plants from the WA-type CMS line and 9311 exhibited stainable pollen grains with no seed set,indicating that 9311 carries minor-effect Rfs for WA-type *** developed an advanced backcross population consisting of plants harboring small regions of donor chromosomal segments from 9311 in the WATianfeng A genetic background with moderate seed setting *** analysis showed that the pollen fertility levels of the backcross individuals are governed by a single gene from 9311 that we named Rf19(t).By use of the RICE 40 K gene chip,three introduced segments were identified in the fertile lines,and a candidate region spanning 4.37–8.29 Mb on chromosome 1 was identified for Rf19(t).Finally,Rf19(t)was fine-mapped to a region of 90 kb between the DNA marker loci STS1-163 and STS1-183,in which eight ORFs were ***,using relative expression analyses,comparative sequence analyses and functional domain analyses,we identified LOC_Os01g10530 as the most likely candidate gene for Rf19(t).Furthermore,Rf19(t)was found to function in fertility restoration,most probably by regulating the degradation of m RNA transcribed from the mitochondrial gene *** results increase our knowledge of fertility restoration in WA-type CMS lines and will facilitate the development of high-quality pairs of WAtype CMS and maintainer lines.

关键词： Rice WA-type CMS Restorer of fertility(Rf)gene gene mapping

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