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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

Primary Studies on Burnup Estimation of Irradiated Uranium by Dtermining 236U/238U in Contaminated Environmental Samples JIANG xiao-yan,ZHANG Ji-long,ZOU Wei,chang zhi-yuan

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Primary Studies on Burnup Estimation of Irradiated Uranium b...

高脂饮食诱导胰岛素抵抗小鼠血浆microRNA表达谱及其与TLR4的关系

作者： JIANG xiao-yan ZHANG Ji-long ZOU Wei chang zhi-yuan

U/U of the environmental sample can indicate the existence of uranium irradiation,and even can be uesd to estimate the burnup of nuclear spent fuel.A study on the burnup estimation of irradiated uranium which was mixed with natural uranium was carried out by measuring the U/U and U/U in the samples by using MC-ICP-MS. According to the equation(1) and(2),a programme for calculating the burnup of the irradiated

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中国免疫学杂志 2016年第12期32卷 1745-1752页

作者：马科朱晓波徐志伟常晓彤河北北方学院附属第一医院检验科张家口075000 河北北方学院临床检验诊断学重点实验室张家口075000

目的:筛选高脂饮食诱导的胰岛素抵抗小鼠,以及应用Toll样受体4(Toll-like receptor4,TLR4)抑制剂TAK-242干预的胰岛素抵抗小鼠血浆差异表达的微小RNA(microRNA,miRNA),探讨胰岛素抵抗、TLR4和差异表达miRNAs的关系。方法:血浆标本来自... 详细信息

目的:筛选高脂饮食诱导的胰岛素抵抗小鼠,以及应用Toll样受体4(Toll-like receptor4,TLR4)抑制剂TAK-242干预的胰岛素抵抗小鼠血浆差异表达的微小RNA(microRNA,miRNA),探讨胰岛素抵抗、TLR4和差异表达miRNAs的关系。方法:血浆标本来自前期实验的3组小鼠,即以普通基础饲料喂养(Low fat diet,LFD)的正常对照组、给予TAK-242的高脂饮食组(Treated high fat diet,HFD-T)和单纯高脂饮食组HFD-C,应用小鼠miRNA芯片检测血浆miRNA表达谱,筛选差异表达的miRNAs;采用实时荧光定量PCR方法验证芯片结果。应用生物信息学方法,以TLR4及其信号传导通路为中心,预测差异表达miRNAs的靶基因,并对靶基因分别进行GO和KEGG富集分析,以判定差异miRNAs主要影响的生物学功能或者通路。结果:miRNA基因芯片筛查结果显示,单纯高脂饮食组与正常饮食组比对,筛选出差异显著的miRNAs共计185种,其中6种miRNAs表达上调,179种miRANs表达下调;给予TAK-242的高脂饮食组与正常饮食组比对,筛选出差异显著的miRANs共计171种,均表达下调;给予TAK-242的高脂饮食组与单纯高脂饮食组比对,筛选出差异表达的miRNAs共计13种,均为下调。生物信息学分析结果显示,以TLR4为中心挖掘与其互作的蛋白质,共发现有10种蛋白;在TAK-242给予的高脂饮食组与单纯高脂饮食组中差异表达倍数均在1 000以上的4种miRNAs(mmu-miR-3095-3p、mmu-miR-5113、mmu-miR-709和mmumiR-335-3p),可在TLR4的互作蛋白质或Toll样受体信号通路中找到其作用的靶基因,发现这些靶基因74%属于生物过程基因,其中转录调控因子占82%。实时荧光定量PCR检测mmu-miR-3095-3p、mmu-miR-5113、mmu-miR-709和mmu-miR-335-3p水平,变化趋势与芯片结果一致。结论:胰岛素抵抗发生时,血浆miRNAs表达谱存在改变,此变化与TLR4及其信号通路相关。该研究结果丰富了胰岛素抵抗发生的机制,为寻找胰岛素抵抗血浆miRNAs诊断标志物提供了实验依据。

关键词：高脂饮食胰岛素抵抗 Toll样受体4 微小RNA表达谱

Tumor inflammation-specific self-amplifying fluorescent molecular probes induce an anti-tumor immune response

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Science China Chemistry 2025年第1期68卷 273-287页

作者： Shuguang Yang Lijun Hu Hong xiao Zecong xiao Xintao Shuai PCFM Lab of Ministry of Education School of Materials Science and Engineering Sun Yat-sen University Department of Ultrasound The Fifth Affiliated Hospital Sun Yat-sen University Department of Medical Ultrasound The Third Affiliated Hospital of Sun Yat-sen University Nanomedicine Research Center The Third Affiliated Hospital of Sun Yat-sen University

Enhancing the concentration of exogenous molecular drugs within the tumor microenvironment through enzyme-catalyzed polymerization presents a novel strategy for cancer therapy. Nonetheless, the optimization of the catalytic efficiency is often impeded by the inefficient expression of enzymes. Herein, we reported a self-amplifying fluorescent molecular probe, Bis-HTPICG, for photodynamic therapy(PDT) and subsequent PDT-induced immunoreaction. The Bis-HTP-ICG probe possesses a noticeable enzyme-catalyzed polymerization facilitated by myeloperoxidase(MPO), a crucial enzyme secreted by neutrophils at inflammation sites. Upon exposure to laser irradiation, Bis-HTP-ICG showed a high PDT efficacy, inducing an acute inflammatory response that stimulates further recruitment of neutrophils and then elevated MPO secretion. The heightened level of MPO enhances the accumulation of the Bis-HTP-ICG via self-polymerization or binding with intratumoral proteins following MPO enzyme catalysis, instigating a self-amplifying chain reaction cycle involving Bis-HTP-ICG, neutrophils and ***, PDT efficiently incites immunogenic cell death(ICD) in tumor cells, initiating an anti-tumor immune response including dendritic cells(DCs) maturation, T cell proliferation and reprogramming of tumor-associated neutrophils(TANs). This work portrays a promising strategy for self-amplification of fluorescent molecular probes through adjustable enzyme levels,potentially offering a unique avenue to enhance the tumor accumulation of molecular drugs for improved tumor therapy.

关键词： fluorescent molecular probes self-amplifying myeloperoxidase photodynamic therapy

Induced pluripotent stem cell-related approaches to generate dopaminergic neurons for Parkinson's disease

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Neural Regeneration Research 2025年第11期20卷 3193-3206页

作者： Ling-xiao Yi Hui Ren Woon Genevieve Saw Li Zeng Eng King Tan zhi Dong Zhou National Neuroscience Institute Singapore Nanyang Technology University Singapore Department of Neurology Singapore General HospitalSingapore Signature Research Program in Neuroscience and Behavioral Disorders Duke-NUS Medical SchoolSingapore

The progressive loss of dopaminergic neurons in affected patient brains is one of the pathological features of Parkinson's disease,the second most common human neurodegenerative *** the detailed pathogenesis accounting for dopaminergic neuron degeneration in Parkinson's disease is still unclear,the advancement of stem cell approaches has shown promise for Parkinson's disease research and *** induced pluripotent stem cells have been commonly used to generate dopaminergic neurons,which has provided valuable insights to improve our understanding of Parkinson's disease pathogenesis and contributed to anti-Parkinson's disease *** current review discusses the practical approaches and potential applications of induced pluripotent stem cell techniques for generating and differentiating dopaminergic neurons from induced pluripotent stem *** benefits of induced pluripotent stem cell-based research are *** dopaminergic neuron differentiation protocols from induced pluripotent stem cells are *** emerging three-dimension-based brain organoid models compared with conventional two-dimensional cell culture are ***,limitations,challenges,and future directions of induced pluripotent stem cell–based approaches are analyzed and proposed,which will be significant to the future application of induced pluripotent stem cell-related techniques for Parkinson's disease.

关键词： dopaminergic neurons induced pluripotent stem cells Parkinson's disease stem cell approaches

Distinct MLT asymmetry of auroral kilometric radiation observed by the FAST satellite

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Earth and Planetary Physics 2025年第1期9卷 188-193页

作者： JiaWen Tang Sai Zhang FuLiang xiao HongMing Yang Si Liu YiHua He chang Yang YuYue Jin ZhouKun Deng Ping Li Archie James Johnston School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Province Higher Education Key Laboratory of Modeling and Monitoring on the Near-Earth Electromagnetic Environments Changsha University of Science and TechnologyChangsha 410114China School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China

Auroral Kilometric Radiation (AKR) is a common radio emission,which can contribute to the magnetosphere-ionosphereatmosphere co u *** emissions have been observed in all magnetic planet magnetospheres of the solar *** this study,using observations from the FAST satellite from 30 August 1996 to 9 September 2001,the distribution of AKR in altitude=500-4500 km and invariant latitude (|ILAT|)=60°-80°has been analyzed.63045 AKR samples have been identified with~48%(52%) samples on the dayside (nightside).Of considerable interest,there is a distinct MLT asymmetry with the high occurrence rate in MLT=05-08 and 18-22(02-05 and 12-17) in the northern (southern) *** distinct MLT asymmetry is associated with the direction of Bxof the interplaneta ry magnetic *** addition,the occurrence rate on the nightside clearly increases as the AE^(*) index *** study further enriches the information and understanding of AKR in the magnetosphere as well as other similar radio emissions.

关键词： asymmetry auroral kilometric radiation interplanetary magnetic field

D-DeepOCSORT: multi-object tracking algorithm based on LiDAR and monocular camera

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Optoelectronics Letters 2025年

作者： HE xiao REN Shuai LIU chang SHI Lei School of Information Engineering， chang'an University School of Control of Robotic and Autonomous Systems， University of California Berkeley

Multi-object tracking is a fundamental problem in computer vision， and DeepOCSORT， due to its reliance on the 2D image position information of targets， tends to exhibit prediction drift. To enhance the tracking stability of DeepOCSORT， this paper proposes a novel multi-sensor data fusion-based multi-object tracking method. Specifically， we build upon the DeepOCSORT foundation and additionally integrate target velocity information directly measured by LiDAR. The introduction of this velocity information is conducted from three perspectives: firstly， during data association， a penalty term is constructed based on the differences in target velocities to constrain generating matches with consistent velocities; secondly， using LiDAR velocity for initialization and online updating of the velocity state within the tracker， making tracking predictions more stable; thirdly， controlling the degree of dependence on velocity information by adjusting the process noise covariance matrix. Evaluation results on the KITTI dataset demonstrate that compared to the original DeepOCSORT， the proposed improved multi-source heterogeneous information fusion method significantly enhances tracking performance， with maximum improvements of 3.35， 3.26， and 3.71 on the HOTA， MOTA， and IDF1 metrics， respectively. This study provides an effective approach to building a more stable and accurate multi-object tracking system.

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Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： Yuhao Peng Yuefeng Song Ihar Razanau Juanxiu xiao Wei xiao Di Hu Guoxiong Wang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences Laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of Belarus State Key Laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University Department of Chemical and Environmental Engineering University of Nottingham Ningbo China

Methane, an abundant one-carbon（C1） resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO2emissions and coke deposition. Electrochemical conversion of methane（ECM） using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO2emission.

关键词： Activation energy

慢病毒介导的Sox-9基因转染对大鼠关节软骨细胞炎性反应的影响

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中华医院感染学杂志 2016年第23期26卷 5342-5345页

作者：宋长志徐小卒吴亚周晓晔纪标秦玲盐城市第一人民医院骨一科江苏盐城22400

目的评价Sox-9基因过表达对IL-β诱导的大鼠关节软骨细胞(RCs)炎性反应的影响,为临床提供参考依据。方法通过慢病毒(Lv-Sox-9)感染的方法在RCs细胞中过表达Sox-9,RT-PCR,Western blot检测病毒感染后大鼠软骨细胞中Sox-9、CollagenⅡ基因... 详细信息

目的评价Sox-9基因过表达对IL-β诱导的大鼠关节软骨细胞(RCs)炎性反应的影响,为临床提供参考依据。方法通过慢病毒(Lv-Sox-9)感染的方法在RCs细胞中过表达Sox-9,RT-PCR,Western blot检测病毒感染后大鼠软骨细胞中Sox-9、CollagenⅡ基因mRNA及蛋白含量;将细胞分为3组,细胞对照组,IL-1β诱导组,对照病毒感染且IL-1β诱导组和Sox-9过表达且IL-1β诱导组,将软骨细胞或者病毒感染后的软骨细胞接种于纳米孔氧化铝膜上,正常条件培养24h后,诱导组细胞培养液中添加5μg/L的IL-1β,继续培养3d,CCK-8法检测细胞增殖活性变化、扫描电镜观察细胞形态及代谢变化。结果通过慢病毒感染的方法可以在大鼠关节软骨细胞中有效上调Sox-9基因的表达,病毒感染后72h,Lv-Sox-9感染组细胞内Sox-9mRNA和蛋白含量均显著高于细胞对照组和对照病毒组;检测结果还显示,Rcs细胞内CollagenⅡ基因在转录和蛋白表达水平均与Sox-9正相关。结论 Sox-9可以作为抗炎治疗的潜在目标基因。

关键词： Sox-9 基因转染慢病毒软骨细胞炎症