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Temporal Control of Cre Recombinase-mediated in Vitro DNA Recombination by Tet-on Gene Expression System

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Acta Biochimica et Biophysica Sinica 2005年第2期37卷 133-138页

作者： zhong-min GUO Kang xu Ying YUE Bing HUANG Xin-Yan DENG Nu-Qi zhong xun HONG Xi-Gu CHEN Dong XIAO Center of Experimental Animals.Sun Yat-Sen (zhongshan) University.Guangzhou 510080.China The First Affiliated Hospital of Sun Yat-Sen University.Sun Yat-Sen University.Guang-hou 510080.China Center of Experimental Animals Sun Yat-Sen (Zhongshan) University Guangzhou 510080 China The First Affiliated Hospital of Sun Yat-Sen University Sun Yat-Sen University Guangzhou 510080 China

Conditional gene expression and gene deletion are important experimental approaches forexamining the functions of particular gene products in mouse models,These strategies exploiting Cre-medi-ated site-specific DNA recombination have been incorporated into transgenic and gene-targeting proceduresto allow in vivo manipulation of DNA in embryonic stem cells(ES cells)or living *** Cre/lox Psystem has become widely used in conditional gene targeting,conditional gene repair and activation,induc-ible chromosome translocation,and chromosome *** this project,we have employed the univer-sal transgenic system and the liver-specific promoter system for tightly temporal and liver-specific control ofCre gene expression in mice that(1)integrates the advantages of the Tet-on gene expression system and Cre//ox P site-mediated gene activation,and(2)simplifies the scheme of animal crosses through a combination oftwo control elements in a single transgene.A liver-specific apoE promoter was inserted into the promotercloning site upstream of the rtTA cassette of pCore construct to generate the transgene construct pApoErtTA-tetO-Cre,followed by demonstrating stringent regulation of doxycycline(Dox)-induced Cre-mediated re-combination in the lox P-flanked transcription STOP cassette-modified BEL-7402 *** is to say,in theabsence of Dox,the Cre gene is not expressed and will not induce site-specific recombination between twolox P sites,whereas on exposure to Dox,the Cre gene will be expressed and the recombination will ***,these data indicate that the Tet-on gene expression system is able to successfully and stringentlycontrol Cre expression in vitro,which lays a solid foundation for efficient and spatio-temporal Cre geneactivation in transgenic mice.

关键词： conditional gene regulation Cre recombinase human apolipoprotein E gene(apoE)promoter Tet-on gene expression system universal transgenic system

Recent Advances in Artificial Sensory Neurons:Biological Fundamentals,Devices,Applications,and Challenges

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Nano-Micro Letters 2025年第3期17卷 168-216页

作者： Shuai zhong Lirou Su mingkun xu Desmond Loke Bin Yu Yishu Zhang Rong Zhao Guangdong Institute of Intelligence Science and Technology HengqinZhuhai 519031People’s Republic of China College of Integrated Circuits Zhejiang UniversityHangzhou 3112000People’s Republic of China ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 310027People’s Republic of China Department of Science Mathematics and TechnologySingapore University of Technology and DesignSingapore 487372Singapore Department of Precision Instruments Tsinghua UniversityBeijing 100084People’s Republic of China Center for Brain‑Inspired Computing Research Tsinghua UniversityBeijing 100084People’s Republic of China IDG/McGovern Institute for Brain Research Tsinghua UniversityBeijing 100084People’s Republic of China

Spike-based neural networks,which use spikes or action potentialsto represent information,have gained a lot of attention because of their high energyefficiency and low power *** fully leverage its advantages,convertingthe external analog signals to spikes is an essential *** including analog-to-digital converters or ring oscillators,and sensorssuffer from high power and area *** efforts are devoted to constructingartificial sensory neurons based on emerging devices inspired by the biologicalsensory *** can simultaneously perform sensing and spike conversion,overcoming the deficiencies of traditional sensory *** review summarizesand benchmarks the recent progress of artificial sensory *** starts with thepresentation of various mechanisms of biological signal transduction,followed bythe systematic introduction of the emerging devices employed for artificial ***,the implementations with different perceptual capabilitiesare briefly outlined and the key metrics and potential applications are also ***,we highlight the challenges and perspectives for the future development of artificial sensory neurons.

关键词： Artificial intelligence Emerging devices Artificial sensory neurons Spiking neural networks Neuromorphic sensing

Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期68卷 46-95页

作者： zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin xu Yu-Wu zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

Cobalamin-dependent radical S-adenosyl-L-methionine protein functions with a partner to successively methylate tricyclic indole alkaloid for chuangxinmycin maturation and derivatization

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Science China Chemistry 2025年第1期68卷 308-316页

作者： Sili Wang Jiancheng Huang Yanan Du Wei Huang Yufeng xue Xiaokun xu Guannan zhong Yuanyuan Shi Bin Hong Xiaoying Bian Wen Liu State Key Laboratory of Chemical Biology Shanghai Institute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences State Key Laboratory of Microbial Technology Shandong University National Health Commission (NHC) Key Laboratory of Biotechnology for Microbial Drugs Institute of Medicinal BiotechnologyChinese Academy of Medical Science & Peking Union Medical College

Cobalamin(Cbl)-dependent radical S-adenosyl-L-methionine(SAM) proteins constitute the largest collection of the radical SAM superfamily that has hundreds of thousands of individual members. Many of these proteins are involved in the biosynthesis of pharmaceutically important natural products to catalyze chemically demanding reactions. In the biosynthetic pathway of chuangxinmycin(CXM), a unique indole alkaloid antibiotic with potent anti-infective activity, functionalization of the characteristic thiopyrano[4,3,2-cd]indole scaffold by regio-and stereoselective C3-methylation is believed to rely on a Cbl-dependent radical process, which, however, remained to be reconstituted biochemically. We here report the dissection of this enzymatic process, which requires the incorporation of Cxm8, a Cbl-dependent radical SAM protein, with Cxm9, a DUF5825family protein that shares no homology to any proteins of known functions. Cxm8 and Cxm9 function together by forming an unexpected heterodimeric complex that selectively catalyzes C3-methylation of the tricyclic indole-S-hetero ring system in a successive manner, achieving CXM and a recently identified, C3-dimethylated congener. Detailed biochemical characterization,isotope labeling, structural simulation and bioinformatics analysis rationalized the catalysis of the Cxm8/Cxm9 complex and particularly the necessity of the DUF5825 protein for C3-methylase activity. This is the first example that a Cbl-dependent protein acts with a partner to exhibit radical SAM activity.

关键词： cbl-dependent radical SAM protein biosynthesis chuangxinmycin stereoselective methylation

阳性淋巴结对数比分期预测Ⅲ期结肠癌预后的价值

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中国医学科学院学报 2016年第3期38卷 294-299页

作者：钟敏儿徐徕徐琼季午阳牛备战邱辉忠吴斌中国医学科学院北京协和医学院北京协和医院基本外科北京100730 重庆市云阳县中医院检验科重庆404500

目的探讨阳性淋巴结对数比（LODDS）分期预测Ⅲ期结肠癌预后的价值。方法回顾性分析了2005年1月至2012年12月在北京协和医院就诊的175例Ⅲ期结肠癌患者的临床资料,比较了淋巴结N分期、淋巴结转移率（LNR）分期和LODDS分期对预后评估的... 详细信息

目的探讨阳性淋巴结对数比（LODDS）分期预测Ⅲ期结肠癌预后的价值。方法回顾性分析了2005年1月至2012年12月在北京协和医院就诊的175例Ⅲ期结肠癌患者的临床资料,比较了淋巴结N分期、淋巴结转移率（LNR）分期和LODDS分期对预后评估的价值。结果不同N分期（χ2=33.1,P=0.000）、LNR分期（χ2=14.3,P=0.001）和LODDS分期（χ2=14.9,P=0.001）的Ⅲ期结肠癌患者5年总生存率差异有统计学意义。单因素分析结果显示：TNM分期（χ2=27.0,P=0.000）、合并癌结节（χ2=3.6,P=0.040）、N分期（χ2=33.1,P=0.000）、LNR分期（χ2=14.3,P=0.001）、LODDS分期（χ2=30.4,P=0.000）与本组Ⅲ期结肠癌患者的预后相关。多因素分析结果显示：TNM分期（HR：1.84,95%CI：1.59～6.29,P=0.001）和LODDS分期（HR：1.34,95%CI：1.01～1.80,P=0.047）是本组Ⅲ期结肠癌患者总生存期的独立预后因素。结论 LODDS分期对于Ⅲ期结肠癌患者术后生存的预后预测具有重要意义。

关键词：阳性淋巴结对数比 N分期淋巴结转移率结肠癌预后

Small extracellular vesicles derived from human induced pluripotent stem cell-differentiated neural progenitor cells mitigate retinal ganglion cell degeneration in a mouse model of optic nerve injury

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Neural Regeneration Research 2025年第2期20卷 587-597页

作者： Tong Li Hui-min Xing Hai-Dong Qian Qiao Gao Sheng-Lan xu Hua Ma Zai-Long Chi State Key Laboratory of Ophthalmology Optometry and Visual ScienceEye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina

Several studies have found that transplantation of neural progenitor cells(NPCs)promotes the survival of injured ***,a poor integration rate and high risk of tumorigenicity after cell transplantation limits their clinical *** extracellular vesicles(sEVs)contain bioactive molecules for neuronal protection and *** studies have shown that stem/progenitor cell-derived sEVs can promote neuronal survival and recovery of neurological function in neurodegenerative eye diseases and other eye *** this study,we intravitreally transplanted sEVs derived from human induced pluripotent stem cells(hiPSCs)and hiPSCs-differentiated NPCs(hiPSC-NPC)in a mouse model of optic nerve *** results show that these intravitreally injected sEVs were ingested by retinal cells,especially those localized in the ganglion cell *** with hiPSC-NPC-derived sEVs mitigated optic nerve crush-induced retinal ganglion cell degeneration,and regulated the retinal microenvironment by inhibiting excessive activation of *** analysis further revealed that hiPSC-NPC derived sEVs transported neuroprotective and anti-inflammatory miRNA cargos to target cells,which had protective effects on RGCs after optic nerve *** findings suggest that sEVs derived from hiPSC-NPC are a promising cell-free therapeutic strategy for optic neuropathy.

关键词： exosome miRNA neural progenitor cell neurodegeneration neuroinflammation neuroprotection optic nerve crush optic neuropathy retinal ganglion cell small extracellular vesicles

Multi-dimensional Bi@C electrocatalyst for Cr3+/Cr2+ redox reaction boosting high-performance iron-chromium flow batteries

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Science China Chemistry 2025年

作者： min Wu mingjun Nan Shumin Liu Caihe zhong Lin Qiao Huamin Zhang Xiangkun Ma Department of Materials Science and Engineering Dalian Maritime University Division of Energy Storage Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences

With the increasing demand for energy storage technology, iron-chromium flow batteries（ICFBs） have been widely concerned because of their price advantage. However, the low electrochemical activity of Cr3+/Cr2+redox couples and the side hydrogen evolution reaction limit the industrial application of ICFBs. A multi-dimensional Bi/carbon composite electrocatalyst（Bi@C）for ICFB is designed and prepared to improve the electrochemical activity of Cr3+/Cr2+redox couples. Benefiting by using the Bimetal organic framework（Bi-MOF） with solid matrix as precursors, Bi nanospheres are highly dispersed on the Bi@C electrocatalyst that effectively enhances the electrochemical activity. The special morphology of Bi@C electrocatalyst helps the transfer of electrons and ions, significantly reducing the polarization of battery. Herein, the 3D porous carbon frames accelerate mass transfer, and the 2D carbon nanobelts and carbon layer coating on 0D Bi nanospheres improve the conductivity of Bi nanospheres. Therefore, the ICFB with multi-dimensional Bi@C electrocatalyst exhibits coulombic efficiency of 98.10% and energy efficiency of 79.14% at 140 mA cm-2, which is higher than ICFBs with commercial graphite carbon electrocatalyst and with heat treatment carbon felt. This work provides a simple and economical method to fabricate a high-performance multidimensional Bi@C electrocatalyst for Cr3+/Cr2+redox couples, boosting the development of ICFBs.

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Enhanced rate capability and cycle stability of Ti2C MXene for sodium storage through an aniline molecules welding strategy

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Tungsten 2025年第1期7卷 161-171页

作者： Hao Chen Ya-Qin Wang Dong-Ting Zhang Bei Zhao min-Peng Li Chen-Yang Li Tian-Peng xu Mao-Cheng Liu State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology School of Computer and Communication Technology Lanzhou University of Technology

MXenes obtained significant attention in the field of energy storage devices due to their characteristic layered structure,modifiable surface functional groups,large electrochemically active surface,and regulable interlayer ***,the self-restacking and sluggish ions diffusion kinetics performance of MXenes during the alkali metal ions insertion/extraction process severely impedes their cycle stability and rate *** paper proposes an aniline molecule welding strategy for welding p-phenylenediamine（PPDA） into the interlayers of Ti2C through a dehydration condensation *** welded PPDA molecules can contribute pillar effect to the layered structure of *** pillar effect effectively maintains the structural stability during the sodium ions insertion/extraction process and effectively expands the interlayer spacing of Ti2C from 1.16 to 1.38 nm,thereby enhancing ions diffusion kinetics performance and improving the long-term cycle *** Ti2C-PPDA demonstrates outstanding Na+storage capability,exhibiting a specific capacity of 100.2 mAh·g-1at a current density of 0.1 A·g-1over 960 cycles and delivering a remarkable rate capability 81.2 mAh·g-1at a current density of 5 A·*** study demonstrates that expanding interlayer spacing is a promising strategy to enhance the Na+storage capacity and improve long-term cycling stability,which provides significant guidance for the design of two-dimensional Na+storage materials with high-rate capability and cycle stability.

关键词： Diffusion kinetics Expanding interlayer spacing Rate capability Sodium ions storage Ti2C

Inhibitory gamma-aminobutyric acidergic neurons in the anterior cingulate cortex participate in the comorbidity of pain and emotion

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Neural Regeneration Research 2025年第10期20卷 2838-2854页

作者： Lu Guan Mengting Qiu Na Li Zhengxiang Zhou Ru Ye Liyan zhong Yashuang xu Junhui Ren Yi Liang Xiaomei Shao Jianqiao Fang Junfan Fang Junying Du Department of Neurobiology and Acupuncture Research Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Key Laboratory for Research of Acupuncture Treatment and Transformation of Emotional Diseases Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Fuchun Community Health Service Center of Fuyang District HangzhouZhejiang ProvinceChina

Pain is often comorbid with emotional disorders such as anxiety and *** of the anterior cingulate cortex has been implicated in pain and pain-related negative emotions that arise from impairments in inhibitory gamma-aminobutyric acid *** review primarily aims to outline the main circuitry(including the input and output connectivity)of the anterior cingulate cortex and classification and functions of different gamma-aminobutyric acidergic neurons;it also describes the neurotransmitters/neuromodulators affecting these neurons,their intercommunication with other neurons,and their importance in mental comorbidities associated with chronic pain *** understanding on their role in pain-related mental comorbidities may facilitate the development of more effective treatments for these ***,the mechanisms that regulate gamma-aminobutyric acidergic systems remain *** is also unclear as to whether the mechanisms are presynaptic or *** exploration of the complexities of this system may reveal new pathways for research and drug development.

关键词： anterior cingulate cortex anxiety chronic pain circuit communication comorbidity depression gamma-aminobutyric acidergic neurons parvalbumin neurons synaptic transmission