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γ-Fe_2O_3:A magnetic separable catalyst for synthesis of 5-substituted 1H-tetrazoles from nitriles and sodium azide

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Chinese Chemical Letters 2010年第9期21卷 1029-1032页

作者： gang Qi Yong dai Department of Chemistry and Biology Yancheng Institute of Technology Yancheng 224051 China

An efficient route for the synthesis of 5-substituted 1H-tetrazole via[2＋3]cycloaddition of nitriles and sodium azide is reported usingγ-Fe2O3 nanoparticles as a magnetic separable *** optimized conditions,the moderate to good yields（71-95%） can be *** catalyst can be easily separated by a magnet and reused for several circles.

关键词： γ-Fe2O3:Magnetic separable catalyst Tetrazole [2+3]Cycloaddition

Gut microbiota-astrocyte axis: new insights into age-related cognitive decline

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Neural Regeneration Research 2025年第4期20卷 990-1008页

作者： Lan Zhang Jingge Wei Xilei Liu dai Li Xiaoqi Pang Fanglian Chen Hailong Cao Ping Lei Haihe Laboratory of Cell Ecosystem Department of GeriatricsTianjin Medical University General HospitalTianjinChina Tianjin Geriatrics Institute Tianjin Medical University General HospitalTianjinChina Department of Gastroenterology and Hepatology Tianjin Medical University General HospitalNational Key Clinical SpecialtyTianjin Institute of Digestive DiseasesTianjin Key Laboratory of Digestive DiseasesTianjinChina Department of Urology Tianjin Medical University General HospitalTianjinChina Tianjin Neurological Institution Tianjin Medical University General HospitalTianjinChina

With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent *** is considered the main risk factor for cognitive decline and acts through alterations in the composition of the gut microbiota,microbial metabolites,and the functions of *** microbiota–gut–brain axis has been the focus of multiple studies and is closely associated with cognitive *** article provides a comprehensive review of the specific changes that occur in the composition of the gut microbiota and microbial metabolites in older individuals and discusses how the aging of astrocytes and reactive astrocytosis are closely related to age-related cognitive decline and neurodegenerative *** article also summarizes the gut microbiota components that affect astrocyte function,mainly through the vagus nerve,immune responses,circadian rhythms,and microbial ***,this article summarizes the mechanism by which the gut microbiota–astrocyte axis plays a role in Alzheimer’s and Parkinson’s *** findings have revealed the critical role of the microbiota–astrocyte axis in age-related cognitive decline,aiding in a deeper understanding of potential gut microbiome-based adjuvant therapy strategies for this condition.

关键词： age aging Alzheimer’s disease astrocytes cognitive decline dementia gut microbiota gut–brain axis microbial metabolites neuroinflammation Parkinson’s disease

Rational design and structural regulation of near-infrared silver chalcogenide quantum dots

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Nano Research 2024年第12期17卷 10585-10606页

作者： Zhen-Ya Liu Wei Zhao Li-Ming Chen Yan-Yan Chen zhi-gang Wang An-An Liu dai-Wen Pang College of Chemistry School of Medicine and Frontiers Science Center for Cell ResponsesFrontiers Science Centre for New Organic MatterTianjin Key Laboratory of Biosensing and Molecular RecognitionResearch Centre for Analytical SciencesNankai UniversityTianjin 300071China School of Chemical and Environmental Engineering Yancheng Teachers UniversityYancheng 224002China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Silver chalcogenides(Ag_(2)E;E=S,Se,or Te)quantum dots(QDs)have emerged as promising candidates for near-infrared(NIR)***,their narrow bandgap and small exciton Bohr radius render the optical properties of Ag_(2)E QDs highly sensitive to surface and size ***,the propensity for the formation of silver impurities and their low solubility product constants pose challenges in their controllable *** advancements have deepened our understanding of the relationship between the multi-hierarchical structure of Ag_(2)E QDs and their optical *** rational design and precise structural regulation,the performance of Ag_(2)E QDs has been significantly enhanced across various *** review provides a comprehensive overview of historical and current progress in the synthesis and structural regulation of Ag_(2)E QDs,encompassing aspects such as size control,crystal structure engineering,and surface/interface ***,it discusses outstanding challenges and potential opportunities in this *** aim of this review is to promote the custom synthesis of Ag_(2)E QDs for applications in biological imaging,and optoelectronics applications.

关键词： silver chalcogenides structural regulation size control crystal engineering surface and interface regulation

In-situ synthesis of quantum dots in the nucleus of live cells

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National Science Review 2024年第3期11卷 172-182页

作者： Yusi Hu zhi-gang Wang Haohao Fu Chuanzheng Zhou Wensheng Cai Xueguang Shao Shu-Lin Liu dai-Wen Pang State Key Laboratory of Medicinal Chemical Biology Frontiers Science Centre for New Organic MatterTianjin Key Laboratory of Biosensing and Molecular Recognition Research Centre for Analytical Sciences College of Chemistry School of Medicine and Frontiers Science Centre for Cell Responses Nankai University Haihe Laboratory of Sustainable Chemical Transformations

The cell nucleus is the main site for the storage and replication of genetic material, and the synthesis of substances in the nucleus is rhythmic, regular and strictly regulated by physiological processes. However,whether exogenous substances, such as nanoparticles, can be synthesized in situ in the nucleus of live cells has not been reported. Here, we have achieved in-situ synthesis of CdSxSe1-xquantum dots（QDs） in the nucleus by regulation of the glutathione（GSH） metabolic pathway. High enrichment of GSH in the nucleus can be accomplished by the addition of GSH with the help of the Bcl-2 protein. Then, high-valence Se is reduced to low-valence Se by glutathione-reductase-catalyzed GSH, and interacts with the Cd precursor formed through Cd and thiol-rich proteins, eventually generating QDs in the nucleus. Our work contributes to a new understanding of the syntheses of substances in the cell nucleus and will pave the way for the development of advanced ‘supercells’.

关键词： glutathione live cell nucleus quantum dot intracellular synthesis

ON EIGENVALUE BOUNDS AND ITERATION METHODS FOR DISCRETE ALGEBRAIC RICCATI EQUATIONS

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Journal of Computational Mathematics 2011年第3期29卷 341-366页

作者： Hua dai Zhong-zhi Bai Department of Mathematics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

We derive new and tight bounds about the eigenvalues and certain sums of the eigenvalues for the unique symmetric positive definite solutions of the discrete algebraic Riccati equations. These bounds considerably improve the existing ones and treat the cases that have been not discussed in the literature. Besides, they also result in completions for the available bounds about the extremal eigenvalues and the traces of the solutions of the discrete algebraic Riccati equations. We study the fixed-point iteration methods for com- puting the symmetric positive definite solutions of the discrete algebraic Riccati equations and establish their general convergence theory. By making use of the Schulz iteration to partially avoid computing the matrix inversions, we present effective variants of the fixed-point iterations, prove their monotone convergence and estimate their asymptotic convergence rates. Numerical results show that the modified fixed-point iteration methods are feasible and effective solvers for computing the symmetric positive definite solutions of the discrete algebraic Riccati equations.

关键词： Discrete algebraic Riccati equation Symmetric positive definite solution Eigenvalue bound Fixed-point iteration Convergence theory.

Nitric Oxide and Brassinosteroids Mediated Fungal Endophyte-Induced Volatile Oil Production Through Protein Phosphorylation Pathways in Atractylodes lancea Plantlets

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Journal of Integrative Plant Biology 2013年第11期55卷 1136-1146页

作者： Cheng-gang Ren Chuan-Chao dai Jiangsu Key Laboratory for Microbes and Functional Genomics Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources College of Life Sciences in Nanjing Normal University

Fungal endophytes have been isolated from almost every plant, infecting their hosts without causing visible disease symptoms, and yet have still proved to be involved in plant secondary metabolites accumulation. To decipher the possible physiological mechanisms of the endophytic fungus-host interaction, the role of protein phosphorylation and the relationship between endophytic fungus-induced kinase activity and nitric oxide （NO） and brassinolide （BL） in endophyte-enhanced volatile oil accumulation in Atractylodes lancea plantlets were investigated using pharmacological and biochemical approaches. Inoculation with the endophytic fungus Gilmaniella sp. ALl2 enhanced the activities of total protein phosphorylation, Ca2^-dependent protein kinase, and volatile oil accumulation in A. lancea plantlets. The upregulation of protein kinase activity could be blocked by the BL inhibitor brassinazole. Furthermore, pretreatments with the NO-specific scavenger cPTIO significantly reduced the increased activities of protein kinases in A. lancea plantlets inoculated with endophytic fungus. Pretreatments with different protein kinase inhibitors also reduced fungus-induced NO production and volatile oil accumulation, but had barely no effect on the BL level. These data suggest that protein phosphorylation is required for endophyte- induced volatile oil production in A. lancea plantlets, and that crosstalk between protein phosphorylation and the NO pathway may occur and act as a downstream signaling event of the BL pathway.

关键词： Atractylodes lancea endophytic fungus protein phosphorylation signal molecule volatile oi1.

ON SMOOTH LU DECOMPOSITIONS WITH APPLICATIONS TO SOLUTIONS OF NONLINEAR EIGENVALUE PROBLEMS

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Journal of Computational Mathematics 2010年第6期28卷 745-766页

We study the smooth LU decomposition of a given analytic functional A-matrix A（A） and its block-analogue. Sufficient conditions for the existence of such matrix decompositions are given, some differentiability about certain elements arising from them are proved, and several explicit expressions for derivatives of the specified elements are provided. By using these smooth LU decompositions, we propose two numerical methods for computing multiple nonlinear eigenvalues of A（A）, and establish their locally quadratic convergence properties. Several numerical examples are provided to show the feasibility and effectiveness of these new methods.

关键词： Matrix-valued function Smooth LU decomposition Pivoting Nonlinear eigenvalue problem Multiple eigenvalue Newton method.

Inhibiting SHP2 reduces glycolysis, promotes microglial M1 polarization, and alleviates secondary inflammation following spinal cord injury in a mouse model

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Neural Regeneration Research 2025年第3期20卷 858-872页

作者： Xintian Ding Chun Chen Heng Zhao Bin dai Lei Ye Tao Song Shuai Huang Jia Wang Tao You Department of Orthopedics The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Department of Orthopedics Provincial Hospital Affiliated to Anhui Medical UniversityHefeiAnhui ProvinceChina

Reducing the secondary inflammatory response, which is partly mediated by microglia, is a key focus in the treatment of spinal cord injury. Src homology 2-containing protein tyrosine phosphatase 2(SHP2), encoded by PTPN11, is widely expressed in the human body and plays a role in inflammation through various mechanisms. Therefore, SHP2 is considered a potential target for the treatment of inflammation-related diseases. However, its role in secondary inflammation after spinal cord injury remains unclear. In this study, SHP2 was found to be abundantly expressed in microglia at the site of spinal cord injury. Inhibition of SHP2 expression using siRNA and SHP2 inhibitors attenuated the microglial inflammatory response in an in vitro lipopolysaccharide-induced model of inflammation. Notably, after treatment with SHP2 inhibitors, mice with spinal cord injury exhibited significantly improved hind limb locomotor function and reduced residual urine volume in the bladder. Subsequent in vitro experiments showed that, in microglia stimulated with lipopolysaccharide, inhibiting SHP2 expression promoted M2 polarization and inhibited M1 polarization. Finally, a co-culture experiment was conducted to assess the effect of microglia treated with SHP2 inhibitors on neuronal cells. The results demonstrated that inflammatory factors produced by microglia promoted neuronal apoptosis, while inhibiting SHP2 expression mitigated these effects. Collectively, our findings suggest that SHP2 enhances secondary inflammation and neuronal damage subsequent to spinal cord injury by modulating microglial phenotype. Therefore, inhibiting SHP2 alleviates the inflammatory response in mice with spinal cord injury and promotes functional recovery postinjury.

关键词： apoptosis glycolysis inflammatory response microglia neurons polarization spinal cord injury Src homology 2-containing protein tyrosine phosphatase 2

Microcapsules with compact wall from hydrocarbon/fluorocarbon composite surfactants for electrophoretic display

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Science China Chemistry 2011年第2期54卷 385-391页

作者： dai RunYing WU gang CHEN HongZheng MOE Key Laboratory of Macromolecule Synthesis and Functionalization Department of Polymer Science and EngineeringState Key Laboratory of Silicon MaterialsZhejiang UniversityHangzhou 310027China

The components and their concentration ratio of surfactant mixture in aqueous solution of gelatin and sodium carboxymethylcellulose (NaCMC) are very important during the preparation of stable microcapsules for electrophoretic *** this work,hydrocarbon/fluorocarbon composite surfactant was introduced for the first time into the capsule wall to improve the chemical resistance and barrier property of the *** investigating surface tension and zeta potential of NaCMC with the mixture of sodium dodecyl sulfate (SDS)/perfluoro-nonene oxy benzene sulfonate (OBS),we found that both the presence of hydrophobic interaction and the hydrogen bonding between NaCMC and SDS/OBS enhanced the adsorption of NaCMC at the oil/water interface and thus facilitated the formation of capsule *** morphology,particle size,surface free energy and thermal stability of the obtained microcapsules were *** results showed that optically transparent microcapsules with uniform size,smooth surface and compact wall can be obtained by adjusting the pH value of the reaction system and the concentration ratio of SDS/*** on the prepared microcapsules,a matrix display prototype operated at 9 V direct current in static driven mode was fabricated.

关键词： microcapsules compact wall sodium carboxymethylcellulose sodium dodecyl sulfate/perfluoro-nonene oxy benzene sulfonate composite surfactant electrophoretic display