A series of amine-bridged bis(phenolate)rare-earth(Sc,Y)aryloxides was synthesized and characterized.These complexes were successfully used for the controlled Lewis pair polymerization(LPP)of functional acrylamides in...A series of amine-bridged bis(phenolate)rare-earth(Sc,Y)aryloxides was synthesized and characterized.These complexes were successfully used for the controlled Lewis pair polymerization(LPP)of functional acrylamides in combination with phosphines,affording a new type of polyacrylamides with predictable molecular weight and low molecular weight distribution.The living nature of this LPP was verified by near-quantitative initiation efficiencies,a linear increase of molecular weight vs monomer-to-initiator ratio and monomer conversion,chain extensions,and the synthesis of well-defined block copolymers.The mechanistic studies were performed through the isolation of a zwitterionic intermediate as well as the end-chain analysis of oligomers,showcasing a rare-earth/phosphine cooperation.Furthermore,the resultant polyacrylamides exhibit outstanding thermal stability and great potential for application in photovoltaic devices.展开更多
To achieve the target of carbon neutrality,it is crucial to develop an efficient and green synthesis methodology with good atomic economy to achieve sufficient utilization of energy and sustainable development.Photoin...To achieve the target of carbon neutrality,it is crucial to develop an efficient and green synthesis methodology with good atomic economy to achieve sufficient utilization of energy and sustainable development.Photoinduced electron transfer reversible addition-fragmentation chain-transfer(PET-RAFT)polymerization is a precise methodology for constructing polymers with well-defined structures.However,conventional semiconductor-mediated PET-RAFT polymerization still has considerable limitations in terms of efficiency as well as the polymerization environment.Herein,sulfur-doped carbonized polymer dots(CPDs)were hydrothermally synthesized for catalysis of aqueous PET-RAFT polymerization at unprecedented efficiency with a highest propagation rate of 5.05 h-1.The resulting polymers have well-controlled molecular weight and narrow molecular weight dispersion(Ð<1.10).Based on the optoelectronic characterizations,we obtained insights into the photoinduced electron transfer process and proposed the mechanism for CPD-mediated PET-RAFT polymerization.In addition,as-synthesized CPDs for PET-RAFT polymerization were also demonstrated to be suitable for a wide range of light sources(blue/green/solar irradiation),numerous monomers,low catalyst loading(low as 0.01 mg mL^(-1)),and multiple polar solvent environments,all of which allowed to achieve efficiencies much higher than those of existing semiconductor-mediated methods.Finally,the CPDs were confirmed to be non-cytotoxic and catalyzed PET-RAFT polymerization successfully in cell culture media,indicating broad prospects in biomedical fields.展开更多
Consisting of natural histidine residues,polyhistidine(PHis)simulates functional proteins.Traditional approaches towards PHis require the protection of imidazole groups before monomer synthesis and polymerization to p...Consisting of natural histidine residues,polyhistidine(PHis)simulates functional proteins.Traditional approaches towards PHis require the protection of imidazole groups before monomer synthesis and polymerization to prevent degradation and side reactions.In the contribution,histidine N-thiocarboxyanhydride(His-NTA)is directly synthesized in aqueous solution without protection.With the self-catalysis of the imidazole side group,the ring-closing reaction to form His-NTA does not require any activating reagent(e.g.,phosphorus tribromide),which is elucidated by density functional theory(DFT)calculations.His-NTA directly polymerizes into PHis bearing unprotected imidazole groups with designable molecular weights(4.2-7.7 kg/mol)and low dispersities(1.10-1.19).Kinetic experiments and Monte Carlo simulations reveal the elementary reactions and the relationship between the conversion of His-NTA and time during polymerization.Block copolymerization of His-NTA with sarcosine N-thiocarboxyanhydride(Sar-NTA)demonstrate versatile construction of functional polypept(o)ides.The triblock copoly(amino acid)PHis-b-PSar-b-PHis is capable to reversibly coordinate with transition metal ions(Fe^(2+),Co^(2+),Ni^(2+),Cu^(2+)and Zn^(2+))to form pH-sensitive hydrogels.展开更多
BACKGROUND Acrylamide(ACR),a toxic compound commonly found in heat-processed foods,poses a serious risk to liver health due to its oxidative and inflammatory effects.AIM To evaluate the hepatoprotective potential of g...BACKGROUND Acrylamide(ACR),a toxic compound commonly found in heat-processed foods,poses a serious risk to liver health due to its oxidative and inflammatory effects.AIM To evaluate the hepatoprotective potential of ginger extract in mitigating ACR-induced liver toxicity in a rat model.METHODS Male Sprague-Dawley rats were randomly assigned into control,ACR-treated,and ACR+ginger-treated groups.Liver function enzymes[alanine aminotransferase(ALT),aspartate aminotransferase(AST),alkaline phosphatase(ALP)],oxidative stress biomarkers[malondialdehyde(MDA),glutathione(GSH),catalase(CAT),superoxide dismutase(SOD)],and histopathological assessments were performed.In addition,gene expression analyses of key antioxidant and inflammatory markers were conducted using quantitative polymerase chain reaction.RESULTS ACR administration significantly increased serum levels of ALT,AST,ALP,and MDA,while reducing levels of GSH,CAT,and SOD.Histological analysis revealed hepatic degeneration and inflammation.Co-administration of ginger extract significantly reversed these effects,restoring antioxidant enzyme levels,reducing oxidative stress,and improving liver histoarchitecture.CONCLUSION Ginger extract exhibited strong hepatoprotective effects against ACR-induced toxicity through antioxidant and anti-inflammatory mechanisms.These findings support the potential role of ginger as a natural dietary intervention for mitigating liver damage caused by environmental toxins.Further clinical studies are recommended to confirm its efficacy in human populations.展开更多
Acrylamide is classified as a Class 2A carcinogen and mainly metabolized to produce hepatotoxicity.Phosphatidylcholine is thought to protect the liver from damage,but the protective role of phosphatidylcholine on acry...Acrylamide is classified as a Class 2A carcinogen and mainly metabolized to produce hepatotoxicity.Phosphatidylcholine is thought to protect the liver from damage,but the protective role of phosphatidylcholine on acrylamide-exposed metabolic disorders remains unclear.We investigated protective effect of phosphatidylcholine on the hepatic metabolism in rats exposed to acrylamide using metabolomics and molecular biology approaches.Overall,32 endogenous effect biomarkers and 4 exposure biomarkers were identified as differential signature metabolites responsible for acrylamide exposure and phosphatidylcholine protection.Acrylamide exposure interferes with glutathione metabolism by consuming antioxidant glutathione,cysteine and L-ascorbic acid,and disrupts lipid and carbohydrate metabolism through reducing carnitine content and increasing lipid peroxidation.The phosphatidylcholine treatment reduces the expression of cytochrome P4502E1,alleviates the oxidative stress and inflammation of the liver,and stabilizes the content of glutathione,and thus alleviates the disorder of glutathione.Meanwhile,phosphatidylcholine shifted acrylamide-induced phosphatidylcholine into lysophosphatidylcholine to storage from lysophosphatidylcholine to diacylglycerol,thereby maintaining metabolic homeostasis of glycerophospholipid.The results suggested that phosphatidylcholine supplementation alleviate the disorder of glutathione and lipid metabolism caused by acrylamide exposure,but not significantly change the levels of mercapturic acid adducts of acrylamide,providing the evidence for phosphatidylcholine protection against acrylamide-induced liver injury.展开更多
Incorporation of acetal groups in the backbone is a potent strategy to create polymers that are cleavable or degradable under acidic conditions.We report here an in-depth study on the ring-closing-opening copolymeriza...Incorporation of acetal groups in the backbone is a potent strategy to create polymers that are cleavable or degradable under acidic conditions.We report here an in-depth study on the ring-closing-opening copolymerization of o-phthalaldehyde(OPA)and epoxide using Lewis pair type two-component organocatalysts for producing acetal-functionalized polyether and polyurethane.Notably,triethylborane as the Lewis acid,in comparison with tri(n-butyl)borane,more effectively enhances the polymerization activity by mitigating borane-induced reduction of the aldehyde group into extra initiating(borinic ester)species.Density functional theory(DFT)calculations present comparable energy barriers of OPA-epoxide cross-propagation and epoxide self-propagation,which is consistent with the experimental finding that an alternating-rich copolymer comprising mostly OPA-epoxide units but also epoxide-epoxide linkages is produced.In particular,when epoxide is added in a large excess,the product becomes a polyether containing acetal functionalities in the central part of the backbone and thus being convertible into polyurethane with refined acid degradability.展开更多
As a powerful synthetic tool,ruthenium-catalyzed ring-opening metathesis polymerization(ROMP)has been widely utilized to prepare diverse heteroatom-containing polymers.In this contribution,we report the synthesis of t...As a powerful synthetic tool,ruthenium-catalyzed ring-opening metathesis polymerization(ROMP)has been widely utilized to prepare diverse heteroatom-containing polymers.In this contribution,we report the synthesis of the novel imine-based polymer through the copolymerization of cyclooctene with cyclic imine comonomer via ROMP.Because of the efficient hydrolysis reactions of the imine group,the generated copolymer can be easily degraded under mild condition.Moreover,the generated degradable product was the telechelic polymer bearing amine group,which was highly challenged for its direct synthesis.And this telechelic polymer could also be used for the further synthesis of new polymer through post-transformation.The introduction of imine unit in this work provides a new example of the degradable polymer synthesis.展开更多
Core-shell colloidal particles with a polymer layer have broad applications in different areas.Herein,we developed a two-step method combining aqueous surface-initiated photoinduced polymerization-induced self-assembl...Core-shell colloidal particles with a polymer layer have broad applications in different areas.Herein,we developed a two-step method combining aqueous surface-initiated photoinduced polymerization-induced self-assembly and photoinduced seeded reversible addition-fragmentation chain transfer(RAFT)polymerization to prepare a diverse set of core-shell colloidal particles with a well-defined polymer layer.Chemical compositions,structures,and thicknesses of polymer layers could be conveniently regulated by using different types of monomers and feed[monomer]/[chain transfer agent]ratios during seeded RAFT polymerization.展开更多
Although solid-state polymer electrolytes(SPEs)are expected to solve the safety hazards and limited energy density in the energy storage systems,they still encounter an inferior electrode/electrolyte interface when pr...Although solid-state polymer electrolytes(SPEs)are expected to solve the safety hazards and limited energy density in the energy storage systems,they still encounter an inferior electrode/electrolyte interface when prepared in an ex situ manner.Recently,in situ polymerization of SPEs favor high interfacial infiltrability,improved interface contact,and reduced interface resistance,owing to the formation of a"superconformal"interface between electrode and electrolyte.Especially,in situ strategies employing ring-opening polymerization(ROP)are emerging as dazzling stars,further enabling moderate polymerization conditions,controllable molecular structure,and reduced interfacial side reaction.As the main monomers that can be in situ polymerized via the ROP strategy,cyclic ethers have been used to construct the CE-SPEs with many merits,including good battery electrochemical performances and a simple assembly process.Here,as a systematic summarization of the existing reports,this review focuses on the polymerization mechanism of ROP,the design principles of CE-SPEs electrolytes,and the recent application of in situ CE-SPEs.In particular,this review thoroughly discusses the selection of different cyclic monomers,initiators and various modification approaches in in situ fabricating CE-SPEs.Ending with offering future challenges and perspectives,this review envisions shedding light on the profound understanding and scientific guidance for further development of high-performance in situ CE-SPEs.展开更多
Acrylamide(AA)is a harmful substance widely found in infant and child biscuits;however,the health hazards of AA,especially endogenous AA,in the biscuit matrix is poorly understood.This study aimed to determine the eff...Acrylamide(AA)is a harmful substance widely found in infant and child biscuits;however,the health hazards of AA,especially endogenous AA,in the biscuit matrix is poorly understood.This study aimed to determine the effects of endogenous(0.11 mg/(kg bw·day))and exogenous(1.31,5.23,and 10.13 mg/(kg bw·day))AA exposure from biscuit diet on the hematology,hormone levels,immune function,and liver and kidney damage in growing female rat pups.For the hematological indices,a quadratic reduction was observed in percentage of neutrophils(Neu%)and percentage of eosinophils(Eos%)in the leukograms and in mean corpuscular hemoglobin concentration and platelet in the erythrograms in all the AA-exposed groups.In terms of hormones,extremely remarkably elevations in estradiol(E_(2))and growth hormone(GH)levels were associated with exogenous AA,and a significant increase in GH levels was noted in the endogenous AA group.Regarding immune function,endogenous and exogenous AA showed a dose-dependent immunotoxic effect on lysozyme(LYSO),nitric oxide(NO),immunoglobulin(Ig)G,and IgM.In particular,the lactate dehydrogenase(LDH)activity was significantly high in the exogenous medium dose(Exo-M)and exogenous high dose(Exo-H)groups,and the percentage of CD3^(+)T cells in the blood and CD8^(+)expression levels in the spleen were significantly elevated in the Exo-H group.For liver and kidney function,exogenous AA had a dose-dependent effect on alanine aminotransferases(ALT),aspartate transferases(AST),alkaline phosphatase(ALP),urea nitrogen(UREA),and creatinine(CREA-S).In addition to the dose-dependent effect on the pathological changes in the liver and kidneys,the endogenous AA group presented with hepatocellular steatosis,kidney inflammatory infiltrates,and glomerular and tubular atrophy.Overall,our findings suggested the dose-dependent harmful effect of endogenous and exogenous AA.Special attention should be paid to the damage caused by exposure to endogenous AA.Stringent AA intake guidelines and measures are required to minimize AA levels in the food matrix.展开更多
Copolymers of fluoroethylene and vinyl ethers(FEVE)are soluble and curable at relatively low temperature,and are used as high-performance coatings and paints.Currently,most market-available FEVE products obtained thro...Copolymers of fluoroethylene and vinyl ethers(FEVE)are soluble and curable at relatively low temperature,and are used as high-performance coatings and paints.Currently,most market-available FEVE products obtained through solution polymerization contain a large fraction of organic solvent,and hence,volatile organic compound(VOC)emissions cause environmental issues.In this study,the emulsion copolymerization of chlorotrifluoroethylene(CTFE)and vinyl ethers using an environmentally friendly emulsification system to produce waterborne FEVE was investigated.In addition to mixed nonionic and ionic surfactants,macromolecular monomer with double bond and polyoxyethylene segments were used in the emulsification system.The effect of adding macromolecular monomer and polyoxyethylene segment length of the nonionic surfactant on emulsion copolymerization were analyzed.An optimized emulsifier system for FEVE is proposed,and the prepared FEVE latexes exhibit excellent storage stability and film formation ability.展开更多
Functional hyperbranched polymers,as an important class of materials,are widely applied in diverse areas.Therefore,the development of simple and efficient reactions to prepare hyperbranched polymers is of great signif...Functional hyperbranched polymers,as an important class of materials,are widely applied in diverse areas.Therefore,the development of simple and efficient reactions to prepare hyperbranched polymers is of great significance.In this work,trialdehydes,diamines,and trimethylsilyl cyanide could easily undergo multicomponent polymerization under mild conditions,producing hyperbranched poly(α-aminonitrile)s with high molecular weights(M_(w) up to 4.87×10^(4))in good yields(up to 85%).The hyperbranched poly(α-aminonitrile)s have good solubility in commonly used organic solvents,high thermal stability as well as morphological stability.Furthermore,due to the numerous aldehyde groups in their branched chains,these hb-poly(α-aminonitrile)s can undergo one-pot,two-step,four-component post-polymerization with high efficiency.This work not only confirms the efficiency of our established catalyst-free multicomponent polymerization of aldehydes,amines and trimethylsilyl cyanide,but also provides a versatile and powerful platform for the preparation of functional hyperbranched polymeric materials.展开更多
Solid polymer electrolytes(SPEs)have garnered considerable interest in the field of lithium metal batteries(LMBs)owing to their exceptional mechanical strength,excellent designability,and heightened safety characteris...Solid polymer electrolytes(SPEs)have garnered considerable interest in the field of lithium metal batteries(LMBs)owing to their exceptional mechanical strength,excellent designability,and heightened safety characteristics.However,their inherently low ion transport efficiency poses a major challenge for their application in LMBs.To address this issue,covalent organic framework(COF)with their ordered ion transport channels,chemical stability,large specific surface area,and designable multifunctional sites has shown promising potential to enhance lithium-ion conduction.Here,we prepared an anionic COF,Tp Pa-COOLi,which can catalyze the ring-opening copolymerization of cyclic lactone monomers for the in situ fabrication of SPEs.The design leverages the high specific surface area of COF to facilitate the absorption of polymerization precursor and catalyze the polymerization within the pores,forming additional COF-polymer junctions that enhance ion transport pathways.The partial exfoliation of COF achieved through these junctions improved its dispersion within the polymer matrix,preserving ion transport channels and facilitating ion transport across COF grain boundaries.By controlling variables to alter the crystallinity of Tp Pa-COOLi and the presence of-COOLi substituents,Tp Pa-COOLi with partial long-range order and-COOLi substituents exhibited superior electrochemical performance.This research demonstrates the potential in constructing high-performance SPEs for LMBs.展开更多
Chain-growth radical polymerization of vinyl monomers is essential for producing a wide range of materials with properties tailored to specific applications.However,the inherent resistance of the polymer's C―C ba...Chain-growth radical polymerization of vinyl monomers is essential for producing a wide range of materials with properties tailored to specific applications.However,the inherent resistance of the polymer's C―C backbone to degradation raises significant concerns regarding long-term environmental persistence,which also limits their potential in biomedical applications.To address these challenges,researchers have developed strategies to either degrade preexisting vinyl polymers or incorporate cleavable units into the backbone to modify them with enhanced degradability.This review explores the various approaches aimed at achieving backbone degradability in chain-growth radical polymerization of vinyl monomers,while also highlighting future research directions for the development of application-driven degradable vinyl polymers.展开更多
The preparation of polypeptide materials in continuous flow reactors shows great potential with improved reproducibility and scalability.However,conventional polypeptide synthesis from the polymerization of N-carboxya...The preparation of polypeptide materials in continuous flow reactors shows great potential with improved reproducibility and scalability.However,conventional polypeptide synthesis from the polymerization of N-carboxyanhydride(NCA)is conducted at relatively slow rates,requiring long tubing or ending up with low-molecular-weight polymers.Inspired by recent advances in accelerated NCA polymerization,we report the crown-ether-catalyzed,rapid synthesis of polypeptide materials in cosolvents in flow reactors.The incorporation of low-polarity dichloromethane and the use of catalysts enabled fast conversion of monomers in 30 min,yielding well-defined polypeptides(up to 30 k Da)through a 20-cm tubing reactor.Additionally,random or block copolypeptides were efficiently prepared by incorporating a second NCA monomer.We believe that this work highlights the accelerated polymerization design in flow polymerization processes,offering the continuous production of polypeptide materials.展开更多
In recent years,cellulose-based fluorescent polymers have received considerable attention.However,conventional modification methods face challenges such as insolubility in most solvents,fluorescence instability,and en...In recent years,cellulose-based fluorescent polymers have received considerable attention.However,conventional modification methods face challenges such as insolubility in most solvents,fluorescence instability,and environmental risks.In this study,a novel biosynthesis strategy was developed to fabricate fluorescent cellulose by adding fluorescent glucose derivatives to a bacterial fermentation broth.The metabolic activity of bacteria is utilized to achieve in situ polymerization of glucose and its derivatives during the synthesis of bacterial cellulose.Owing to the structural similarity between triphenylamine-modified glucose(TPA-Glc N)and glucose monomers,the TPA-Glc N were efficiently assimilated by the bacterial cells and incorporated into the cellulose matrix,resulting in a uniform distribution of fluorescence.The fluorescence color and intensity of the obtained cellulose could be adjusted by varying the amount of the fluorescent glucose derivatives.Compared to the fluorescent cellulose synthesized through physical dyeing,the fluorescence of the products obtained by in situ polymerization showed higher intensity and stability.Furthermore,fluorescent bacterial cellulose can be hydrolyzed into nanocellulose-based ink,which demonstrates exceptional anti-counterfeiting capabilities under UV light.This biosynthesis method not only overcomes the limitations of traditional modification techniques but also highlights the potential of microbial systems as platforms for synthesizing functional polymers.展开更多
Acrylamide(AA)is a neurotoxin and carcinogen that formed during the thermal food processing.Conventional quantification techniques are difficult to realize on-site detection of AA.Herein,a flower-like bimetallic FeCu ...Acrylamide(AA)is a neurotoxin and carcinogen that formed during the thermal food processing.Conventional quantification techniques are difficult to realize on-site detection of AA.Herein,a flower-like bimetallic FeCu nanozyme(FeCuzyme)sensor and portable platform were developed for naked-eye and on-site detection of AA.The FeCuzyme was successfully prepared and exhibited flower-like structure with 3D catalytic centers.Fe/Cu atoms were considered as active center and ligand frameworks were used as cofactor,resulting in collaborative substrate-binding features and remarkably peroxidase-like activity.During the catalytic process,the 3,3′,5,5′-tetrame-thylbenzidine(TMB)oxidation can be quenched by glutathione(GSH),and then restored after thiolene Michael addition reaction between GSH and AA.Given the“on–off–on”effect for TMB oxidation and high PODlike activity,FeCuzyme sensor exhibited a wide linear relationship from 0.50 to 18.00μM(R^(2)=0.9987)and high sensitivity(LOD=0.2360μM)with high stability.The practical application of FeCuzyme sensor was successfully validated by HPLC method.Furthermore,a FeCuzyme portable platform was designed with smartphone/laptop,and which can be used for naked-eye and on-site quantitative determination of AA in real food samples.This research provides a way for rational design of a novel nanozyme-based sensing platform for AA detection.展开更多
Exploration of new green polymerization strategies for the construction of conjugated polymers is important but challengeable.In this work,a multicomponent polymerization of acetylarenes,alkynones and ammonium acetate...Exploration of new green polymerization strategies for the construction of conjugated polymers is important but challengeable.In this work,a multicomponent polymerization of acetylarenes,alkynones and ammonium acetate for in situ construction of conjugated poly(triarylpyridine)s was developed.The polymerization reactions of diacetylarenes,aromatic dialkynones and NH_(4)OAc were performed in dimethylsulfoxide(DMSO)under heating in the presence of potassium tert-butoxide(t-BuOK),affording four conjugated poly(2,4,6-triarylpyridine)s(PTAPs)in satisfactory yields.The resulting PTAPs have good solubility in common organic solvents and high thermal stability with 5%weight loss temperatures reaching up to 460℃.They are also electrochemically active.The PTAPs incorporating tetraphenylethene units manifest aggregation-induced emission features.Moreover,through simply being doped into poly(vinyl alcohol)(PVA)matrix,the polymer and model compound containing triphenylamine moieties exhibit room-temperature phosphorescence properties with ultralong lifetimes up to 696.2 ms and high quantum yields up to 28.7%.This work not only provides a facile green synthetic route for conjugated polymers but also offers new insights into the design of advanced materials with unique photophysical properties.展开更多
Living cationic polymerization of 4-acetoxystyrene(STO)was conducted in CH_(2)Cl_(2) at-15℃ using a dicumyl chloride(DCC)/SnCl_(4)/nBu_(4)NBr initiating system.Impurity moisture initiation was inhibited by adding pro...Living cationic polymerization of 4-acetoxystyrene(STO)was conducted in CH_(2)Cl_(2) at-15℃ using a dicumyl chloride(DCC)/SnCl_(4)/nBu_(4)NBr initiating system.Impurity moisture initiation was inhibited by adding proton trap 2,6-di-tert-butylpyridine(DTBP),and the controlled initiation of DCC was confirmed by ^(1)H nuclear magnetic resonance(^(1)H-NMR)spectroscopy and matrix-assisted laser desorption ionization time-offlight mass(MALDI-TOF-MS)spectrometry.The polymerization kinetics were analyzed to for optimizing the polymerization rate.Allyl-telechelic PSTOs(allyl-PSTO-allyl)with molecular weight(Mn)range of 3540–7800 g/mol and narrow molecular weight dispersity(Mw/Mn)about 1.25 were prepared through nucleophilic substitution with allyltrimethylsilane(ATMS)at approximately 40%monomer conversion.The experimental results indicate that the substitution efficiency of ATMS increased with higher ATMS concentration,temperature,and extended reaction time.Nearly unity ally-functionality for allyl-PSTO-allyl was achieved by adding sufficient SnCl_(4) prior to the substitution.展开更多
Our previous study has demonstrated that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A_(1))can prevent acrylamide(ACR)-induced cytotoxicity in small intestine cells.However,the potential mechanism re...Our previous study has demonstrated that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A_(1))can prevent acrylamide(ACR)-induced cytotoxicity in small intestine cells.However,the potential mechanism remains poorly understood.In this study,ACR treatment was found to increase the levels of 8-hydroxy deoxyguanine(8-OHdG)and phosphorated histone H_(2)AX(γH_(2)AX),two DNA damage markers,thereby resulting in cell cycle arrest in the G2/M phase;whereas both A_(1) and D-A_(1) could prevent the phosphorylation of ataxia telangiectasia mutated(ATM)and checkpoint kinase 2(Chk2),and then regulate the expression of G2/M phase-related proteins,finally maintaining normal cell cycle progression.Moreover,A_(1) and D-A_(1) could increase the B cell lymphoma 2(Bcl-2)/Bcl2-associated X(Bax)ratio and decrease the expression of cleaved caspase-3 and cleaved caspase-9 proteins to alleviate ACR-induced cell apoptosis,which might be related to the inhibition of the mitogen-activated protein kinase(MAPK)pathway.More importantly,A_(1) showed no remarkable variation in inhibitory effect before and after digestion,indicating that it can endure gastrointestinal digestion and may be a promising phytochemical to alleviate ACR-induced intestinal cell damage.展开更多
基金supported by National Natural Science Foundation of China(21871204,22371198)Postgraduate Research&Practice Innovation Program of Jiangsu Province。
文摘A series of amine-bridged bis(phenolate)rare-earth(Sc,Y)aryloxides was synthesized and characterized.These complexes were successfully used for the controlled Lewis pair polymerization(LPP)of functional acrylamides in combination with phosphines,affording a new type of polyacrylamides with predictable molecular weight and low molecular weight distribution.The living nature of this LPP was verified by near-quantitative initiation efficiencies,a linear increase of molecular weight vs monomer-to-initiator ratio and monomer conversion,chain extensions,and the synthesis of well-defined block copolymers.The mechanistic studies were performed through the isolation of a zwitterionic intermediate as well as the end-chain analysis of oligomers,showcasing a rare-earth/phosphine cooperation.Furthermore,the resultant polyacrylamides exhibit outstanding thermal stability and great potential for application in photovoltaic devices.
基金supported by the National Natural Science Foundation of China(NSFC)under Grant No.22035001 and No.52233005.
文摘To achieve the target of carbon neutrality,it is crucial to develop an efficient and green synthesis methodology with good atomic economy to achieve sufficient utilization of energy and sustainable development.Photoinduced electron transfer reversible addition-fragmentation chain-transfer(PET-RAFT)polymerization is a precise methodology for constructing polymers with well-defined structures.However,conventional semiconductor-mediated PET-RAFT polymerization still has considerable limitations in terms of efficiency as well as the polymerization environment.Herein,sulfur-doped carbonized polymer dots(CPDs)were hydrothermally synthesized for catalysis of aqueous PET-RAFT polymerization at unprecedented efficiency with a highest propagation rate of 5.05 h-1.The resulting polymers have well-controlled molecular weight and narrow molecular weight dispersion(Ð<1.10).Based on the optoelectronic characterizations,we obtained insights into the photoinduced electron transfer process and proposed the mechanism for CPD-mediated PET-RAFT polymerization.In addition,as-synthesized CPDs for PET-RAFT polymerization were also demonstrated to be suitable for a wide range of light sources(blue/green/solar irradiation),numerous monomers,low catalyst loading(low as 0.01 mg mL^(-1)),and multiple polar solvent environments,all of which allowed to achieve efficiencies much higher than those of existing semiconductor-mediated methods.Finally,the CPDs were confirmed to be non-cytotoxic and catalyzed PET-RAFT polymerization successfully in cell culture media,indicating broad prospects in biomedical fields.
基金financially supported by the National Natural Science Foundation of China(Nos.22271252 and 22201105)。
文摘Consisting of natural histidine residues,polyhistidine(PHis)simulates functional proteins.Traditional approaches towards PHis require the protection of imidazole groups before monomer synthesis and polymerization to prevent degradation and side reactions.In the contribution,histidine N-thiocarboxyanhydride(His-NTA)is directly synthesized in aqueous solution without protection.With the self-catalysis of the imidazole side group,the ring-closing reaction to form His-NTA does not require any activating reagent(e.g.,phosphorus tribromide),which is elucidated by density functional theory(DFT)calculations.His-NTA directly polymerizes into PHis bearing unprotected imidazole groups with designable molecular weights(4.2-7.7 kg/mol)and low dispersities(1.10-1.19).Kinetic experiments and Monte Carlo simulations reveal the elementary reactions and the relationship between the conversion of His-NTA and time during polymerization.Block copolymerization of His-NTA with sarcosine N-thiocarboxyanhydride(Sar-NTA)demonstrate versatile construction of functional polypept(o)ides.The triblock copoly(amino acid)PHis-b-PSar-b-PHis is capable to reversibly coordinate with transition metal ions(Fe^(2+),Co^(2+),Ni^(2+),Cu^(2+)and Zn^(2+))to form pH-sensitive hydrogels.
文摘BACKGROUND Acrylamide(ACR),a toxic compound commonly found in heat-processed foods,poses a serious risk to liver health due to its oxidative and inflammatory effects.AIM To evaluate the hepatoprotective potential of ginger extract in mitigating ACR-induced liver toxicity in a rat model.METHODS Male Sprague-Dawley rats were randomly assigned into control,ACR-treated,and ACR+ginger-treated groups.Liver function enzymes[alanine aminotransferase(ALT),aspartate aminotransferase(AST),alkaline phosphatase(ALP)],oxidative stress biomarkers[malondialdehyde(MDA),glutathione(GSH),catalase(CAT),superoxide dismutase(SOD)],and histopathological assessments were performed.In addition,gene expression analyses of key antioxidant and inflammatory markers were conducted using quantitative polymerase chain reaction.RESULTS ACR administration significantly increased serum levels of ALT,AST,ALP,and MDA,while reducing levels of GSH,CAT,and SOD.Histological analysis revealed hepatic degeneration and inflammation.Co-administration of ginger extract significantly reversed these effects,restoring antioxidant enzyme levels,reducing oxidative stress,and improving liver histoarchitecture.CONCLUSION Ginger extract exhibited strong hepatoprotective effects against ACR-induced toxicity through antioxidant and anti-inflammatory mechanisms.These findings support the potential role of ginger as a natural dietary intervention for mitigating liver damage caused by environmental toxins.Further clinical studies are recommended to confirm its efficacy in human populations.
基金supported by the National Natural Science Foundation of China(21976156)。
文摘Acrylamide is classified as a Class 2A carcinogen and mainly metabolized to produce hepatotoxicity.Phosphatidylcholine is thought to protect the liver from damage,but the protective role of phosphatidylcholine on acrylamide-exposed metabolic disorders remains unclear.We investigated protective effect of phosphatidylcholine on the hepatic metabolism in rats exposed to acrylamide using metabolomics and molecular biology approaches.Overall,32 endogenous effect biomarkers and 4 exposure biomarkers were identified as differential signature metabolites responsible for acrylamide exposure and phosphatidylcholine protection.Acrylamide exposure interferes with glutathione metabolism by consuming antioxidant glutathione,cysteine and L-ascorbic acid,and disrupts lipid and carbohydrate metabolism through reducing carnitine content and increasing lipid peroxidation.The phosphatidylcholine treatment reduces the expression of cytochrome P4502E1,alleviates the oxidative stress and inflammation of the liver,and stabilizes the content of glutathione,and thus alleviates the disorder of glutathione.Meanwhile,phosphatidylcholine shifted acrylamide-induced phosphatidylcholine into lysophosphatidylcholine to storage from lysophosphatidylcholine to diacylglycerol,thereby maintaining metabolic homeostasis of glycerophospholipid.The results suggested that phosphatidylcholine supplementation alleviate the disorder of glutathione and lipid metabolism caused by acrylamide exposure,but not significantly change the levels of mercapturic acid adducts of acrylamide,providing the evidence for phosphatidylcholine protection against acrylamide-induced liver injury.
基金financially supported by the National Key R&D Program of China(No.2022YFC2805103)the National Natural Science Foundation of China(Nos.52022031 and 52263001)the Foundation from Qinghai Science and Technology Department(No.2022-ZJ-944Q)。
文摘Incorporation of acetal groups in the backbone is a potent strategy to create polymers that are cleavable or degradable under acidic conditions.We report here an in-depth study on the ring-closing-opening copolymerization of o-phthalaldehyde(OPA)and epoxide using Lewis pair type two-component organocatalysts for producing acetal-functionalized polyether and polyurethane.Notably,triethylborane as the Lewis acid,in comparison with tri(n-butyl)borane,more effectively enhances the polymerization activity by mitigating borane-induced reduction of the aldehyde group into extra initiating(borinic ester)species.Density functional theory(DFT)calculations present comparable energy barriers of OPA-epoxide cross-propagation and epoxide self-propagation,which is consistent with the experimental finding that an alternating-rich copolymer comprising mostly OPA-epoxide units but also epoxide-epoxide linkages is produced.In particular,when epoxide is added in a large excess,the product becomes a polyether containing acetal functionalities in the central part of the backbone and thus being convertible into polyurethane with refined acid degradability.
基金financially supported by National Key R&D Program of China(No.2021YFA1501700)CAS Project for Young Scientists in Basic Research(No.YSBR-094)+1 种基金Natural Science Foundation of Anhui Province(Nos.2308085Y35 and 2023AH030002)Hefei Natural Science Foundation(No.202304)。
文摘As a powerful synthetic tool,ruthenium-catalyzed ring-opening metathesis polymerization(ROMP)has been widely utilized to prepare diverse heteroatom-containing polymers.In this contribution,we report the synthesis of the novel imine-based polymer through the copolymerization of cyclooctene with cyclic imine comonomer via ROMP.Because of the efficient hydrolysis reactions of the imine group,the generated copolymer can be easily degraded under mild condition.Moreover,the generated degradable product was the telechelic polymer bearing amine group,which was highly challenged for its direct synthesis.And this telechelic polymer could also be used for the further synthesis of new polymer through post-transformation.The introduction of imine unit in this work provides a new example of the degradable polymer synthesis.
基金support from the Science and Technology Program of Guangzhou(No.2024A04J2821)the National Natural Science Foundation of China(Nos.52222301,22171055)the Guangdong Natural Science Foundation for Distinguished Young Scholar(No.2022B1515020078)。
文摘Core-shell colloidal particles with a polymer layer have broad applications in different areas.Herein,we developed a two-step method combining aqueous surface-initiated photoinduced polymerization-induced self-assembly and photoinduced seeded reversible addition-fragmentation chain transfer(RAFT)polymerization to prepare a diverse set of core-shell colloidal particles with a well-defined polymer layer.Chemical compositions,structures,and thicknesses of polymer layers could be conveniently regulated by using different types of monomers and feed[monomer]/[chain transfer agent]ratios during seeded RAFT polymerization.
基金supported by the National Natural Science Foundation of China(22022813)the Zhejiang Provincial Natural Science Foundation of China(LQ24B030002)the China Postdoctoral Science Foundation(2022M722729,2023T160571).
文摘Although solid-state polymer electrolytes(SPEs)are expected to solve the safety hazards and limited energy density in the energy storage systems,they still encounter an inferior electrode/electrolyte interface when prepared in an ex situ manner.Recently,in situ polymerization of SPEs favor high interfacial infiltrability,improved interface contact,and reduced interface resistance,owing to the formation of a"superconformal"interface between electrode and electrolyte.Especially,in situ strategies employing ring-opening polymerization(ROP)are emerging as dazzling stars,further enabling moderate polymerization conditions,controllable molecular structure,and reduced interfacial side reaction.As the main monomers that can be in situ polymerized via the ROP strategy,cyclic ethers have been used to construct the CE-SPEs with many merits,including good battery electrochemical performances and a simple assembly process.Here,as a systematic summarization of the existing reports,this review focuses on the polymerization mechanism of ROP,the design principles of CE-SPEs electrolytes,and the recent application of in situ CE-SPEs.In particular,this review thoroughly discusses the selection of different cyclic monomers,initiators and various modification approaches in in situ fabricating CE-SPEs.Ending with offering future challenges and perspectives,this review envisions shedding light on the profound understanding and scientific guidance for further development of high-performance in situ CE-SPEs.
文摘Acrylamide(AA)is a harmful substance widely found in infant and child biscuits;however,the health hazards of AA,especially endogenous AA,in the biscuit matrix is poorly understood.This study aimed to determine the effects of endogenous(0.11 mg/(kg bw·day))and exogenous(1.31,5.23,and 10.13 mg/(kg bw·day))AA exposure from biscuit diet on the hematology,hormone levels,immune function,and liver and kidney damage in growing female rat pups.For the hematological indices,a quadratic reduction was observed in percentage of neutrophils(Neu%)and percentage of eosinophils(Eos%)in the leukograms and in mean corpuscular hemoglobin concentration and platelet in the erythrograms in all the AA-exposed groups.In terms of hormones,extremely remarkably elevations in estradiol(E_(2))and growth hormone(GH)levels were associated with exogenous AA,and a significant increase in GH levels was noted in the endogenous AA group.Regarding immune function,endogenous and exogenous AA showed a dose-dependent immunotoxic effect on lysozyme(LYSO),nitric oxide(NO),immunoglobulin(Ig)G,and IgM.In particular,the lactate dehydrogenase(LDH)activity was significantly high in the exogenous medium dose(Exo-M)and exogenous high dose(Exo-H)groups,and the percentage of CD3^(+)T cells in the blood and CD8^(+)expression levels in the spleen were significantly elevated in the Exo-H group.For liver and kidney function,exogenous AA had a dose-dependent effect on alanine aminotransferases(ALT),aspartate transferases(AST),alkaline phosphatase(ALP),urea nitrogen(UREA),and creatinine(CREA-S).In addition to the dose-dependent effect on the pathological changes in the liver and kidneys,the endogenous AA group presented with hepatocellular steatosis,kidney inflammatory infiltrates,and glomerular and tubular atrophy.Overall,our findings suggested the dose-dependent harmful effect of endogenous and exogenous AA.Special attention should be paid to the damage caused by exposure to endogenous AA.Stringent AA intake guidelines and measures are required to minimize AA levels in the food matrix.
基金financially supported by the joint lab of Shanghai Huayi 3F New Materials Co.,Ltd.Donghua University。
文摘Copolymers of fluoroethylene and vinyl ethers(FEVE)are soluble and curable at relatively low temperature,and are used as high-performance coatings and paints.Currently,most market-available FEVE products obtained through solution polymerization contain a large fraction of organic solvent,and hence,volatile organic compound(VOC)emissions cause environmental issues.In this study,the emulsion copolymerization of chlorotrifluoroethylene(CTFE)and vinyl ethers using an environmentally friendly emulsification system to produce waterborne FEVE was investigated.In addition to mixed nonionic and ionic surfactants,macromolecular monomer with double bond and polyoxyethylene segments were used in the emulsification system.The effect of adding macromolecular monomer and polyoxyethylene segment length of the nonionic surfactant on emulsion copolymerization were analyzed.An optimized emulsifier system for FEVE is proposed,and the prepared FEVE latexes exhibit excellent storage stability and film formation ability.
基金financially supported by the Scientific Research Start-up Fund Project of Anhui Polytechnic University for Introducing Talents(No.2022YQQ081)Natural Science Research Project of Anhui Educational Committee(No.2024AH050133)the National Natural Science Foundation of China(No.22001078).
文摘Functional hyperbranched polymers,as an important class of materials,are widely applied in diverse areas.Therefore,the development of simple and efficient reactions to prepare hyperbranched polymers is of great significance.In this work,trialdehydes,diamines,and trimethylsilyl cyanide could easily undergo multicomponent polymerization under mild conditions,producing hyperbranched poly(α-aminonitrile)s with high molecular weights(M_(w) up to 4.87×10^(4))in good yields(up to 85%).The hyperbranched poly(α-aminonitrile)s have good solubility in commonly used organic solvents,high thermal stability as well as morphological stability.Furthermore,due to the numerous aldehyde groups in their branched chains,these hb-poly(α-aminonitrile)s can undergo one-pot,two-step,four-component post-polymerization with high efficiency.This work not only confirms the efficiency of our established catalyst-free multicomponent polymerization of aldehydes,amines and trimethylsilyl cyanide,but also provides a versatile and powerful platform for the preparation of functional hyperbranched polymeric materials.
基金the National Natural Science Foundation of China(grant nos.52020105012 and 523B2025)the Innovation and Talent Recruitment Base of New Energy Chemistry and Device(B21003)the Analysis and Testing Center of HUST for the assistance in analysis and testing。
文摘Solid polymer electrolytes(SPEs)have garnered considerable interest in the field of lithium metal batteries(LMBs)owing to their exceptional mechanical strength,excellent designability,and heightened safety characteristics.However,their inherently low ion transport efficiency poses a major challenge for their application in LMBs.To address this issue,covalent organic framework(COF)with their ordered ion transport channels,chemical stability,large specific surface area,and designable multifunctional sites has shown promising potential to enhance lithium-ion conduction.Here,we prepared an anionic COF,Tp Pa-COOLi,which can catalyze the ring-opening copolymerization of cyclic lactone monomers for the in situ fabrication of SPEs.The design leverages the high specific surface area of COF to facilitate the absorption of polymerization precursor and catalyze the polymerization within the pores,forming additional COF-polymer junctions that enhance ion transport pathways.The partial exfoliation of COF achieved through these junctions improved its dispersion within the polymer matrix,preserving ion transport channels and facilitating ion transport across COF grain boundaries.By controlling variables to alter the crystallinity of Tp Pa-COOLi and the presence of-COOLi substituents,Tp Pa-COOLi with partial long-range order and-COOLi substituents exhibited superior electrochemical performance.This research demonstrates the potential in constructing high-performance SPEs for LMBs.
基金funding from the National Natural Science Foundation of China(No.22401037)funding from JST CREST(No.JPMJCR23L1)。
文摘Chain-growth radical polymerization of vinyl monomers is essential for producing a wide range of materials with properties tailored to specific applications.However,the inherent resistance of the polymer's C―C backbone to degradation raises significant concerns regarding long-term environmental persistence,which also limits their potential in biomedical applications.To address these challenges,researchers have developed strategies to either degrade preexisting vinyl polymers or incorporate cleavable units into the backbone to modify them with enhanced degradability.This review explores the various approaches aimed at achieving backbone degradability in chain-growth radical polymerization of vinyl monomers,while also highlighting future research directions for the development of application-driven degradable vinyl polymers.
基金financially supported by the National Natural Science Foundation of China(No.22101194)Natural Science Foundation of Jiangsu Province(No.BK20210733)+3 种基金Suzhou Municipal Science and Technology Bureau(No.ZXL2021447)Collaborative Innovation Center of Suzhou Nano Science&Technologythe 111 ProjectJoint International Research Laboratory of Carbon-Based Functional Materials and Devices。
文摘The preparation of polypeptide materials in continuous flow reactors shows great potential with improved reproducibility and scalability.However,conventional polypeptide synthesis from the polymerization of N-carboxyanhydride(NCA)is conducted at relatively slow rates,requiring long tubing or ending up with low-molecular-weight polymers.Inspired by recent advances in accelerated NCA polymerization,we report the crown-ether-catalyzed,rapid synthesis of polypeptide materials in cosolvents in flow reactors.The incorporation of low-polarity dichloromethane and the use of catalysts enabled fast conversion of monomers in 30 min,yielding well-defined polypeptides(up to 30 k Da)through a 20-cm tubing reactor.Additionally,random or block copolypeptides were efficiently prepared by incorporating a second NCA monomer.We believe that this work highlights the accelerated polymerization design in flow polymerization processes,offering the continuous production of polypeptide materials.
基金supported by the National Natural Science Foundation of China(No.22376111)Shandong Provincial Natural Science Foundation(No.ZR2024YQ026)+2 种基金for Excellent Young Scholars,Taishan Scholar Foundation of Shandong Province(No.tsqn202408237)Youth Innovation Team Project for Talent Introduction and Cultivation in Universities of Shandong Province(No.096-1622002)the Research Foundation for Distinguished Scholars of Qingdao Agricultural University(No.663-1117015)。
文摘In recent years,cellulose-based fluorescent polymers have received considerable attention.However,conventional modification methods face challenges such as insolubility in most solvents,fluorescence instability,and environmental risks.In this study,a novel biosynthesis strategy was developed to fabricate fluorescent cellulose by adding fluorescent glucose derivatives to a bacterial fermentation broth.The metabolic activity of bacteria is utilized to achieve in situ polymerization of glucose and its derivatives during the synthesis of bacterial cellulose.Owing to the structural similarity between triphenylamine-modified glucose(TPA-Glc N)and glucose monomers,the TPA-Glc N were efficiently assimilated by the bacterial cells and incorporated into the cellulose matrix,resulting in a uniform distribution of fluorescence.The fluorescence color and intensity of the obtained cellulose could be adjusted by varying the amount of the fluorescent glucose derivatives.Compared to the fluorescent cellulose synthesized through physical dyeing,the fluorescence of the products obtained by in situ polymerization showed higher intensity and stability.Furthermore,fluorescent bacterial cellulose can be hydrolyzed into nanocellulose-based ink,which demonstrates exceptional anti-counterfeiting capabilities under UV light.This biosynthesis method not only overcomes the limitations of traditional modification techniques but also highlights the potential of microbial systems as platforms for synthesizing functional polymers.
基金supported by the National Natural Science Foundation of China(32060577 and 32360619)Natural Science Foundation of Jiangxi Province(20224ACB203016 and 20212BAB203034)the Open Project of China Food Flavor and Nutrition Health Innovation Center(CFC2023B-013).
文摘Acrylamide(AA)is a neurotoxin and carcinogen that formed during the thermal food processing.Conventional quantification techniques are difficult to realize on-site detection of AA.Herein,a flower-like bimetallic FeCu nanozyme(FeCuzyme)sensor and portable platform were developed for naked-eye and on-site detection of AA.The FeCuzyme was successfully prepared and exhibited flower-like structure with 3D catalytic centers.Fe/Cu atoms were considered as active center and ligand frameworks were used as cofactor,resulting in collaborative substrate-binding features and remarkably peroxidase-like activity.During the catalytic process,the 3,3′,5,5′-tetrame-thylbenzidine(TMB)oxidation can be quenched by glutathione(GSH),and then restored after thiolene Michael addition reaction between GSH and AA.Given the“on–off–on”effect for TMB oxidation and high PODlike activity,FeCuzyme sensor exhibited a wide linear relationship from 0.50 to 18.00μM(R^(2)=0.9987)and high sensitivity(LOD=0.2360μM)with high stability.The practical application of FeCuzyme sensor was successfully validated by HPLC method.Furthermore,a FeCuzyme portable platform was designed with smartphone/laptop,and which can be used for naked-eye and on-site quantitative determination of AA in real food samples.This research provides a way for rational design of a novel nanozyme-based sensing platform for AA detection.
基金supported by the National Natural Science Foundation of China(No.22071166)the Priority Academic Program Development of Jiangsu High Education Institutions(PAPD).
文摘Exploration of new green polymerization strategies for the construction of conjugated polymers is important but challengeable.In this work,a multicomponent polymerization of acetylarenes,alkynones and ammonium acetate for in situ construction of conjugated poly(triarylpyridine)s was developed.The polymerization reactions of diacetylarenes,aromatic dialkynones and NH_(4)OAc were performed in dimethylsulfoxide(DMSO)under heating in the presence of potassium tert-butoxide(t-BuOK),affording four conjugated poly(2,4,6-triarylpyridine)s(PTAPs)in satisfactory yields.The resulting PTAPs have good solubility in common organic solvents and high thermal stability with 5%weight loss temperatures reaching up to 460℃.They are also electrochemically active.The PTAPs incorporating tetraphenylethene units manifest aggregation-induced emission features.Moreover,through simply being doped into poly(vinyl alcohol)(PVA)matrix,the polymer and model compound containing triphenylamine moieties exhibit room-temperature phosphorescence properties with ultralong lifetimes up to 696.2 ms and high quantum yields up to 28.7%.This work not only provides a facile green synthetic route for conjugated polymers but also offers new insights into the design of advanced materials with unique photophysical properties.
基金financially supported by the National Natural Science Foundation of China(No.52373011)。
文摘Living cationic polymerization of 4-acetoxystyrene(STO)was conducted in CH_(2)Cl_(2) at-15℃ using a dicumyl chloride(DCC)/SnCl_(4)/nBu_(4)NBr initiating system.Impurity moisture initiation was inhibited by adding proton trap 2,6-di-tert-butylpyridine(DTBP),and the controlled initiation of DCC was confirmed by ^(1)H nuclear magnetic resonance(^(1)H-NMR)spectroscopy and matrix-assisted laser desorption ionization time-offlight mass(MALDI-TOF-MS)spectrometry.The polymerization kinetics were analyzed to for optimizing the polymerization rate.Allyl-telechelic PSTOs(allyl-PSTO-allyl)with molecular weight(Mn)range of 3540–7800 g/mol and narrow molecular weight dispersity(Mw/Mn)about 1.25 were prepared through nucleophilic substitution with allyltrimethylsilane(ATMS)at approximately 40%monomer conversion.The experimental results indicate that the substitution efficiency of ATMS increased with higher ATMS concentration,temperature,and extended reaction time.Nearly unity ally-functionality for allyl-PSTO-allyl was achieved by adding sufficient SnCl_(4) prior to the substitution.
基金supported by the project from National Natural Science Foundation of China(31671962)Excellent Youth Foundation of Education Department of Hunan Province(23B0229)Fundamental Research Funds for the Central Universities(2662019PY034).
文摘Our previous study has demonstrated that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A_(1))can prevent acrylamide(ACR)-induced cytotoxicity in small intestine cells.However,the potential mechanism remains poorly understood.In this study,ACR treatment was found to increase the levels of 8-hydroxy deoxyguanine(8-OHdG)and phosphorated histone H_(2)AX(γH_(2)AX),two DNA damage markers,thereby resulting in cell cycle arrest in the G2/M phase;whereas both A_(1) and D-A_(1) could prevent the phosphorylation of ataxia telangiectasia mutated(ATM)and checkpoint kinase 2(Chk2),and then regulate the expression of G2/M phase-related proteins,finally maintaining normal cell cycle progression.Moreover,A_(1) and D-A_(1) could increase the B cell lymphoma 2(Bcl-2)/Bcl2-associated X(Bax)ratio and decrease the expression of cleaved caspase-3 and cleaved caspase-9 proteins to alleviate ACR-induced cell apoptosis,which might be related to the inhibition of the mitogen-activated protein kinase(MAPK)pathway.More importantly,A_(1) showed no remarkable variation in inhibitory effect before and after digestion,indicating that it can endure gastrointestinal digestion and may be a promising phytochemical to alleviate ACR-induced intestinal cell damage.
