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Synthesis of poly(thiourethane-alt-thioester)by alternating ring-opening copolymerization of N-thiocarboxyanhydrides and episulfides

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Science China Chemistry 2024年第9期67卷 3091-3097页

作者： Wei Xiong Tianjun Yue Haiwang Lai Chunyan Lyu Weimin Ren Hua Lu Beijing National laboratory for molecular Sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China State Key laboratory of Fine Chemicals Dalian University of TechnologyDalian 116081China

Polythiourethanes(PTU)and polythioesters(PTE)derived from renewable sources are emerging sustainable polymers for their excellent degradability and ***,P(TU-alt-TE)copolymers have been rare and challenging to ***,we report the efficient synthesis of novel P(TU-alt-TE)copolymers via the alternating copolymerization of N-thiocarboxyanhydrides(NTA)/episufides(ES)and provide mechanistic insight into the alternating chain propagation process via density functional theory(DFT)*** incorporation of ESs into traditional peptide backbone is capable of adjusting the glass transition temperature below thermal decomposition temperature,which confers better thermal processability by regulating the rigidity of the backbone and the hydrogen bond interaction among the polymer *** PTUs with tailored properties are accessible by altering the feeding ratio of NTAs and(bifunctional)***,the thiourethane in the backbone can endow interesting underwater adhesion properties to the *** the broad scope of NTA and ES monomers,this method is expected to provide a promising and general route to a wide range of P(TU-alt-TE)copolymers with diverse properties.

关键词： poly(thiourethane-alt-thioester) alternating ring-opening copolymerization N-thiocarboxyanhydrides episulfides

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TRAIL and Celastrol Combinational Treatment Suppresses Proliferation, Migration, and Invasion of Human Glioblastoma Cells via Targeting Wnt/β-catenin Signaling Pathway

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Chinese Journal of Integrative Medicine 2024年第4期30卷 322-329页

作者： QIN Jing-jing NIU Meng-da CHA Zhe GENG Qing-hua LI Yu-lin REN Chun-guang David P.Molloy YU Hua-rong Research Center of Neuroscience School of Basic Medical SciencesChongqing Medical UniversityChongqing(400016)China laboratory of Developmental biology Department of Cell Biology and GeneticsSchool of Basic Medical SciencesChongqing Medical UniversityChongqing(400016)China Department of Biochemistry and molecular biology School of Basic Medical SciencesChongqing Medical UniversityChongqing(400016)China

Objective To investigate the mechanistic basis for the anti-proliferation and anti-invasion effect of tumor necrosis factor-related apoptosis-induced ligand(TRAIL)and celastrol combination treatment(TCCT)in glioblastoma *** Cell counting kit-8 was used to detect the effects of different concentrations of celastrol(0-16µmol/L)and TRAIL(0-500 ng/mL)on the cell viability of glioblastoma cells.U87 cells were randomly divided into 4 groups,namely control,TRAIL(TRAIL 100 ng/mL),Cel(celastrol 0.5µmol/L)and TCCT(TRAIL 100 ng/mL+celastrol 0.5µmol/L).Cell proliferation,migration,and invasion were detected by colony formation,wound healing,and Transwell assays,*** reverse transcription polymerase chain reaction and Western blotting were performed to assess the levels of epithelial-mesenchymal transition(EMT)markers(zona occludens,N-cadherin,vimentin,zinc finger E-box-binding homeobox,Slug,and β-catenin).Wnt pathway was activated by lithium chloride(LiCl,20 mol/L)and the mechanism for action of TCCT was *** Celastrol and TRAIL synergistically inhibited the proliferation,migration,invasion,and EMT of U87 cells(P<0.01).TCCT up-regulated the expression of GSK-3β and down-regulated the expression of β-catenin and its associated proteins(P<0.05 or P<0.01),including c-Myc,Cyclin-D1,and matrix metalloproteinase(MMP)-*** addition,LiCl,an activator of the Wnt signaling pathway,restored the inhibitory effects of TCCT on the expression of β-catenin and its downstream genes,as well as the migration and invasion of glioblastoma cells(P<0.05 or P<0.01).Conclusions Celastrol and TRAIL can synergistically suppress glioblastoma cell migration,invasion,and EMT,potentially through inhibition of Wnt/β-catenin *** underlies a novel mechanism of action for TCCT as an effective therapy for glioblastoma.

关键词： celastrol Chinese medicine tumor necrosis factor-related apoptosis-induced ligand glioblastoma β-catenin Tripterygium wilfordii

Interparticle energy transfer between NaNdF_(4) and NaYbF_(4) in self-assembled nanostructures

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Journal of Rare Earths 2024年第6期42卷 1029-1035,I0001页

作者： Xinyu Chen Haoze Yang Yuyang Gu Chenqing Wen Yishuo Sun Jiaming Ke Wei Feng Department of Chemistry and State Key laboratory of molecular Engineering of Polymers Fudan University Shanghai200433China

Forster resonance energy transfer(FRET)is a widely used spectroscopic *** development of donor-acceptor combinations is essential to advance this *** make the energy transfer efficiency independent of the external environment,we explored the potential of constructing donor—acceptor combinations with lanthanide ion-doped nanoparticles(LNPs),in which the 4f electrons of the lanthanide ions are shielded by the 5s and 6p ***-radiative energy transfer between LNPs was demonstrated in self-assembled nanostructures and core-shell structure of LNPs was used to control the distance between donor and acceptor in self-assembled *** emission intensity ratio of donor and acceptor illustrates that the energy transfer efficiency decreases significantly with increasing distance and the effective energy transfer distance is 8.5 nm,showing the potential of using LNPs as donor-acceptor pairs in the construction of distance-dependent energy transfer system.

关键词： Lanthanide nanoparticles Self-assembly Energy transfer Distance Epitaxialgrowth Rare earths

Ultracycles consisting of macrocycles

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Chinese Chemical Letters 2024年第5期35卷 183-188页

作者： Wen-Hui Mi Teng-Yu Huang Yu-Fei Ao Xu-Dong Wang Qi-Qiang Wang De-Xian Wang Beijing National laboratory for molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Presented here is a one-pot strategy starting from rationally designed macrocyclic precursors for the diverse construction of sophisticated *** type and amount of the base were found to significantly influence the macrocyclization *** use of 4.0 *** resulted in ultracycles of both types A and B while the presence of CsF larger than 6.0 *** only type B *** of anion template increased the total yields and affected the distribution of the *** ultracycles can accommodate large organic dicarboxylates anions via multiple anion-πand hydrogen bonds,and show selectivity to the size-matched heptanedioate(C7^(2−)).Based on all possible species and relevant equilibrium constants as well as material and charge balances,a numerical iterative algorithm was developed and applied to fit the association constants of B2H with dicarboxylates from glutarate(C5^(2−))to octanedioate(C8^(2−)),which gave association constants up to 10^(3) L/mol.

关键词： Ultracycles Diversity-oriented synthesis Anion recognition Anion-πinteraction

Nitrogen-doping boosts *CO utilization and H2O activation on copper for improving CO2 reduction to C2+ products

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Green Energy & Environment 2024年第9期9卷 1459-1465页

作者： Yisen Yang Zhonghao Tan Jianling Zhang Jie Yang Renjie Zhang Sha Wang Yi Song Zhuizhui Su Beijing National laboratory for molecular Sciences CAS Laboratory of Colloid and Interface and Thermodynamics CAS Research/Education Center for Excellence in Molecular Sciences Center for Carbon Neutral Chemistry Institute of Chemistry Chinese Academy of Sciences School of Chemical Sciences University of Chinese Academy of Sciences Key laboratory of Photochemistry CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences

To improve the electrocatalytic transformation of carbon dioxide （CO2） to multi-carbon (C2+) products is of great *** we developed a nitrogen-doped Cu catalyst,by which the maximum C2+Faradaic efficiency can reach 72.7%in flow-cell system,with the partial current density reaching 0.62 A *** in situ Raman spectra demonstrate that the *CO adsorption can be strengthened on such a N-doped Cu catalyst,thus promoting the*CO utilization in the subsequent C–C coupling ***,the water activation can be well enhanced by N doping on Cu *** to the synergistic effects,the selectivity and activity for C2+products over the N-deoped Cu catalyst are much improved.

关键词： Electrocatalytic CO 2 reduction reaction Copper catalyst Doping Multi-carbon products In situ Raman measurement

Thiazoloisoindigo-based Polymer Semiconductors: Synthesis,Structure-Property Relationship, Charge Carrier Polarity, and Field-Effect Transistor Performance

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Chinese Journal of Polymer Science 2024年第1期42卷 24-31,I0006页

作者： Bo-Wen Li Miao Xiong Mei-Hua Liu Zhi-Gao Li Long Sang Zi-Han Xiong Biao Xiao Jian Pei Xiao-Bo Wan Key laboratory of Optoelectronic Chemical Materials and Devices Ministry of EducationSchoolofOptoelectronic Materials&TechnologyJianghan UniversityWuhan430056China Bejing National laboratoryfor molecular Sciences the Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Developing new polymeric semiconductors with excellent device performance is essential for organic electronics. Herein, we synthesized two new thiazoloisoindigo(Tz II)-based polymers, namely, P(Tz II-d Th-d Th) and P(Tz II-d Th-d Tz), by copolymerizing thiophene-flanked Tz II with bithiophene and bithiazole, respectively. Owing to the more electron-deficient nature of bithiazole than bithiophene, P(Tz II-d Th-d Tz)possesses deeper LUMO/HOMO levels of-3.45/-5.47 e V than P(Tz II-d Th-d Th)(-3.34/-5.32 e V). The organic field-effect transistor(OFET) devices based on P(Tz II-d Th-d Th) exhibited p-type behaviors with an average hole mobility value as high as 1.43 cm^(2)·V^(-1)·s^(-1), while P(Tz II-d Th-d Tz)showed typical ambipolar characteristics with average hole and electron mobilities of 0.38 and 0.56 cm^(2)·V^(-1)·s^(-1). In addition, we compared the performances of both polymers with other Tz II-based polymers reported in our previous work, and showed that the charge carrier polarity can be manipulated by adjusting the number of the thiophene units between the acceptor unit. As the increase of the number of thiophene rings,charge carrier polarity shifts from electron-dominated ambipolar transport to hole-dominated ambipolar transport and then to unipolar hole transport in OFETs, which provides an effective molecular design strategy for further optimization of polymer OFET performance.

关键词： Field-effect transistor Charge carrier polarity Thiazoloisoindigo

How plants sense and respond to osmotic stress

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Journal of Integrative Plant biology 2024年第3期66卷 394-423页

作者： Bo Yu Dai-Yin Chao Yang Zhao Shanghai Center for Plant Stress biology CAS Center for Excellence in Molecular Plant SciencesThe Chinese Academy of SciencesShanghai 200032China Key laboratory of Plant Carbon Capture The Chinese Academy of SciencesShanghai 200032China National Key laboratory of Plant molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyThe Chinese Academy of SciencesShanghai 200032China University of Chinese Academy of Sciences Beijing 100049China

Drought is one of the most serious abiotic stresses to land *** sense and respond to drought stress to survive under water *** have studied how plants sense drought stress,or osmotic stress caused by drought,ever since Charles Darwin,and gradually obtained clues about osmotic stress sensing and signaling in *** stress is a physical stimulus that triggers many physiological changes at the cellular level,including changes in turgor,cell wall stiffness and integrity,membrane tension,and cell fluid volume,and plants may sense some of these stimuli and trigger downstream *** this review,we emphasized water potential and movements in organisms,compared putative signal inputs in cell wall-containing and cell wall-free organisms,prospected how plants sense changes in turgor,membrane tension,and cell fluid volume under osmotic stress according to advances in plants,animals,yeasts,and bacteria,summarized multilevel biochemical and physiological signal outputs,such as plasma membrane nanodomain formation,membrane water permeability,root hydrotropism,root halotropism,Casparian strip and suberin lamellae,and finally proposed a hypothesis that osmotic stress responses are likely to be a cocktail of signaling mediated by multiple *** also discussed the core scientific questions,provided perspective about the future directions in this field,and highlighted the importance of robust and smart root systems and efficient source-sink allocations for generating future high-yield stress-resistant crops and plants.

关键词： cell volume drought membrane tension osmotic stress turgor

Enzymatically controlled DNA tetrahedron nanoprobes for specific imaging of ATP in tumor

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Chinese Chemical Letters 2024年第8期35卷 221-224页

作者： Xiaohong Wen Mei Yang Lie Li Mingmin Huang Wei Cui Suping Li Haiyan Chen Chen Li Qiuping Guo College of biology State Key Laboratory of Chemo/Biosensing and ChemometricsCollege of Chemistry and Chemical EngineeringKey Laboratory for Bio-Nanotechnology and Molecular Engineering of Hunan ProvinceHunan UniversityChangsha 410082China

Intracellular ATP is an emerging biomarker for cancer early diagnosis because it is a key messenger for regulating the proliferation and migration of cancer ***,the conventional ATP biosensing strat-egy is often limited by the undesired on-target off-tumor ***,we reported a novel strategy to design enzymatically controlled DNA tetrahedron nanoprobes(En-DT)for biosensing and imaging ATP in tumor *** En-DT was designed via rational engineering of structure-switching aptamers with the incorporation of an enzyme-activatable site and further conjugation on the DNA *** En-DT could be catalytically activated by apurinic/apyrimidinic endonuclease 1(APE1)in cancer cells,but they did not respond to ATP in normal cells,thereby enabling cancer-specific ATP biosensing and imaging in vitro and in vivo with improved tumor *** strategy would facilitate the precise detection of a broad range of biomarker in tumors and may promote the development of smart probes for cancer diagnosis.

关键词： Enzyme-controlled APE1 DNA tetrahedron Cancer-specific ATP biosensing

Amphipathicity mediated endocytosis of mesoporous silica nanoparticles with tunable frameworks

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Nano Research 2024年第9期17卷 8350-8359页

作者： Runfeng Lin Tiancong Zhao Liang Chen Minchao Liu Hongyue Yu Ruicong Wang Minjia Yuan Xiaomin Li Dongyuan Zhao Department of Chemistry State Key Laboratory of Molecular Engineering of PolymersiChemShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200433China Shanghai Qiran Biotechnology Co. Ltd.Shanghai 201702China

Due to the amphiphilic nature of phospholipids in the cell membrane,the amphipathicity of the nanomedicine plays a crucial role in the ***,limited biological characterization methods restrict the study of the state of nanoparticles with different amphiphilicities on cell *** understanding of interaction of amphiphilic particle with cell membrane is still ***,by combining the dissipative particle dynamics(DPD)with the framework construction of mesoporous silica nanoparticles(MSNs),we demonstrate the enhanced endocytosis induced by the *** results confirm that the presence of hydrophobic groups on the surface of nanoparticles can disturb the integrity of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine(POPC)membrane and induce activation of phospholipids to a higher energy level,thereby facilitating the wrapping of *** validate the simulation findings,uniform MSNs with hydrophilic pure silica framework and two types of amphiphilic MSNs with varying hydrophilic organic groups in the framework are rationally synthesized by using different silane *** obtained three kinds of MSNs show similar diameter(~100 nm)and mesopores(~2 nm),but distinct hydrophobicity/hydrophilicity *** phenyl-bridged MSN with a carbon content of 27.1%exhibits enhanced cellular uptake,consistent with the theoretical simulation *** work sheds light on how the surface amphipathicity influences endocytosis through the interaction with cell membrane.

关键词： mesoporous silica nanoparticles mesoporous organosilica endocytosis cell membrane amphipathicity