Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration vi...Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration via paracrine signaling;however,their clinical applications are limited by potential risks such as tumorigenesis and xenogeneic immune rejection,which are similar to the risks associated with other stem cell transplantations.The present study therefore focuses on small extracellular vesicles derived from hair follicle neural crest stem cells,which preserve the bioactive properties of the parent cells while avoiding the transplantation-associated risks.In vitro,small extracellular vesicles derived from hair follicle neural crest stem cells significantly enhanced the proliferation,migration,tube formation,and barrier function of perineurial cells,and subsequently upregulated the expression of tight junction proteins.Furthermore,in a rat model of sciatic nerve defects bridged with silicon tubes,treatment with small extracellular vesicles derived from hair follicle neural crest stem cells resulted in higher tight junction protein expression in perineurial cells,thus facilitating neural tissue regeneration.At 10 weeks post-surgery,rats treated with small extracellular vesicles derived from hair follicle neural crest stem cells exhibited improved nerve function recovery and reduced muscle atrophy.Transcriptomic and micro RNA analyses revealed that small extracellular vesicles derived from hair follicle neural crest stem cells deliver mi R-21-5p,which inhibits mothers against decapentaplegic homolog 7 expression,thereby activating the transforming growth factor-β/mothers against decapentaplegic homolog signaling pathway and upregulating hyaluronan synthase 2 expression,and further enhancing tight junction protein expression.Together,our findings indicate that small extracellular vesicles derived from hair follicle neural crest stem cells promote the proliferation,migration,and tight junction protein formation of perineurial cells.These results provide new insights into peripheral nerve regeneration from the perspective of perineurial cells,and present a novel approach for the clinical treatment of peripheral nerve defects.展开更多
Microwave has been widely used in many fields,including communication,medical treatment and military industry;however,the corresponding generated radiations have been novel hazardous sources of pollution threating hu...Microwave has been widely used in many fields,including communication,medical treatment and military industry;however,the corresponding generated radiations have been novel hazardous sources of pollution threating human’s daily life.Therefore,designing high-performance microwave absorption materials(MAMs)has become an indispensable requirement.Recently,metal-organic frameworks(MOFs)have been considered as one of the most ideal precursor candidates of MAMs because of their tunable structure,high porosity and large specific surface area.Usually,MOF-derived MAMs exhibit excellent electrical conductivity,good magnetism and sufficient defects and interfaces,providing obvious merits in both impedance matching and microwave loss.In this review,the recent research progresses on MOF-derived MAMs were profoundly reviewed,including the categories of MOFs and MOF composites precursors,design principles,preparation methods and the relationship between mechanisms of microwave absorption and microstructures of MAMs.Finally,the current challenges and prospects for future opportunities of MOF-derived MAMs are also discussed.展开更多
At present,natural gas accounts for a low proportion in China's primary energy consumption structure and is highly dependent on foreign sources.Changqing gas province of the Ordos Basin where PetroChina Changqing ...At present,natural gas accounts for a low proportion in China's primary energy consumption structure and is highly dependent on foreign sources.Changqing gas province of the Ordos Basin where PetroChina Changqing Oilfield Company(referred to as Changqing Oilfield)is located is one of China's four major natural gas production bases.It bears the important responsibility for ensuring people's livelihood and promoting the healthy development of society economy.In recent years,Changqing Oilfield actively implements national instructive spirit on vigorously promoting domestic oil and gas exploration and development strength and formulates the secondary acceleration development strategies.Its annual natural gas production in 2020 reaches 448.5×10^(8) m^(3) and oil and gas equivalent exceeds 6000×10^(4) t,tamping its important position of“Western Daqing”in this industry.In order to further promote the continuous stable production and realize the goal of quality and efficiency improvement in Changqing gas province,this paper analyzes the situations and challenges of natural gas development in this gas province,prepares the development technological countermeasures and forecast the natural gas development prospect.And the following research results are obtained.First,the natural gas exploration and development in Changqing gas province is divided into four stages and the main technologies for the development of low-permeability carbonate gas reservoir,low-permeability sandstone gas reservoir and tight sandstone gas reservoir are formed.Second,the natural gas development in Changqing gas province faces six challenges,such as low reserve production degree,sharp decline of production rates and complex distribution of remaining undeveloped reserves of developed gas fields.And twenty-six development technological countermeasures are put forward correspondingly,such as well pattern thickening,extension and reserve increase,secondary production layer potential tapping and fine gas well management.Third,the development direction and goal of natural gas development in Changqing gas province is to pay equal attention to the stable production of old gas fields and the production increase of new areas and carry out conventional gas and unconventional gas research simultaneously.In conclusion,the annual natural gas production of Changqing gas province will maintain a sound momentum of steady growth and will exceed 500×10^(8) m^(3) at the end of the 14th Five-Year Plan and maintain at a stable level for a long term,which is conducive to the optimization of domestic energy consumption structure and realization of“carbon peak and carbon neutrality”.展开更多
To overcome the pain and risk of hypoglycemia in insulin administration,glucose-responsive microneedles have been developed by researchers,which could release insulin according to the blood glucose level.We designed a...To overcome the pain and risk of hypoglycemia in insulin administration,glucose-responsive microneedles have been developed by researchers,which could release insulin according to the blood glucose level.We designed a kind of particles by a reversible addition-fragmentation chain transfer(RAFT)method containing a phenylboronic acid group as the sensor of glucose and carrier of insulin.poly(ethylene glycol)(PEG)-2-(dodecylthio(thiocarbonyl)thio)-2-methylpropionic acid(DDMAT)was synthesized as a macromolecular RAFT agent,which was then reacted with 3-acrylamidophenylboronic acid(AAPBA)to synthesize the block copolymer PEG-b-PAAPBA.Glucose-responsive particles loaded with insulin were prepared by self-assembly based on hydrophilic-hydrophobic interactions.Microneedle patches loaded with glucose-responsive particles were prepared using hyaluronic acid as the substrate.The insulin release behavior of the particles in glucose solutions of 0,100,and 400 mg/dL showed significant glucose responsiveness and good biosafety.The results of blood glucose control experiments in rats indicate that a single microneedle patch can effectively maintain normal blood glucose for over 7 h.展开更多
Although stimuli-responsive polymers have appeared as promising materials for drug administration,the effectiveness of these materials on various bioinspired stimuli is still open for dispute.In this work,the stimuli-...Although stimuli-responsive polymers have appeared as promising materials for drug administration,the effectiveness of these materials on various bioinspired stimuli is still open for dispute.In this work,the stimuli-responsive behaviors of radical-containing nonamphiphilic copolymers were investigated using electron paramagnetic resonance(EPR)spectroscopy while altering the pH and reductant concentration.The concentration of radicals in the aqueous solution had a considerable impact on self-assembly.The nitroxide radicals(hydrophobic)were converted to hydroxylamine(hydrophilic)when ascorbic acid(Asc)was added as a reductant,and the assemblies were switched to dissolution with a rate control behavior.The behavior of morphological change was observed in the acidic pH due to the disproportionation reaction of nitroxide radicals forming cationic species.The acquired results give new insights into the colloidal nanoparticles of nonamphiphilic copolymers and encourage the development of comparable responsive nanoparticles with intriguing drug delivery applications.展开更多
The structure of polyolefin has an important influence on its performance and application.Ethylene/1-hexene copolymerization is one of the important ways to control the structure of the polyolefin.However,research on ...The structure of polyolefin has an important influence on its performance and application.Ethylene/1-hexene copolymerization is one of the important ways to control the structure of the polyolefin.However,research on the ethylene/1-hexene copolymerization catalyzed by nickel complexes with different steric ligands remains to be refined.Here,three α-dimine nickel catalysts are used to study the ligand effect on catalytic performance in the ethylene/1-hexene copolymerization.Reaction activity,molecular weight,phase-transition temperature and branching density of the resultant copolymer are measured to evaluate the catalytic performance.The results indicate that the steric ligands could exert great effect on the copolymerization.As for the chemical valence of Ni species,detailed EPR demonstrate that the presence of excess xo-catalyst can reduce Ni(Ⅱ)to the lower valence and affect the catalytic performance.展开更多
Lactic acidosis is a hallmark of the tumor microenvironment(TME)and a critical impediment to the efficacy of transarterial chemoembolization(TACE)in hepatocellular carcinoma(HCC).Incomplete embolization preserves viab...Lactic acidosis is a hallmark of the tumor microenvironment(TME)and a critical impediment to the efficacy of transarterial chemoembolization(TACE)in hepatocellular carcinoma(HCC).Incomplete embolization preserves viable tumor cells that amplify hypoxia-driven glycolysis,generating a lactic acid-rich milieu that drives treatment resistance,skews immune populations toward immunosuppressive phenotypes,and impairs cytotoxic T lymphocyte function.In this review,we elucidate the pathways through which lactic acidosis compromises TACE efficacy and propose novel strategies for its mitigation.We examine emerging approaches,including systemic or intra-arterial alkalization,targeted inhibition of lactate production and export,and calcium carbonate nanoparticles,and evaluate their respective merits and limitations.Finally,we propose a combination regimen of calcium carbonate nanoparticles,lactate-targeting agents,and TACE to achieve precise drug delivery,synergistic lactic acid depletion,and enhanced antitumor immunity.These integrated strategies have the potential to convert immunologically“cold”HCC lesions into“hot”ones,thereby improving TACE outcomes and disease control.展开更多
基金supported by the National Natural Science Foundation of China,No.81571211(to FL)the Natural Science Foundation of Shanghai,No.22ZR1476800(to CH)。
文摘Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration via paracrine signaling;however,their clinical applications are limited by potential risks such as tumorigenesis and xenogeneic immune rejection,which are similar to the risks associated with other stem cell transplantations.The present study therefore focuses on small extracellular vesicles derived from hair follicle neural crest stem cells,which preserve the bioactive properties of the parent cells while avoiding the transplantation-associated risks.In vitro,small extracellular vesicles derived from hair follicle neural crest stem cells significantly enhanced the proliferation,migration,tube formation,and barrier function of perineurial cells,and subsequently upregulated the expression of tight junction proteins.Furthermore,in a rat model of sciatic nerve defects bridged with silicon tubes,treatment with small extracellular vesicles derived from hair follicle neural crest stem cells resulted in higher tight junction protein expression in perineurial cells,thus facilitating neural tissue regeneration.At 10 weeks post-surgery,rats treated with small extracellular vesicles derived from hair follicle neural crest stem cells exhibited improved nerve function recovery and reduced muscle atrophy.Transcriptomic and micro RNA analyses revealed that small extracellular vesicles derived from hair follicle neural crest stem cells deliver mi R-21-5p,which inhibits mothers against decapentaplegic homolog 7 expression,thereby activating the transforming growth factor-β/mothers against decapentaplegic homolog signaling pathway and upregulating hyaluronan synthase 2 expression,and further enhancing tight junction protein expression.Together,our findings indicate that small extracellular vesicles derived from hair follicle neural crest stem cells promote the proliferation,migration,and tight junction protein formation of perineurial cells.These results provide new insights into peripheral nerve regeneration from the perspective of perineurial cells,and present a novel approach for the clinical treatment of peripheral nerve defects.
基金Open access funding provided by Shanghai Jiao Tong University.
文摘Microwave has been widely used in many fields,including communication,medical treatment and military industry;however,the corresponding generated radiations have been novel hazardous sources of pollution threating human’s daily life.Therefore,designing high-performance microwave absorption materials(MAMs)has become an indispensable requirement.Recently,metal-organic frameworks(MOFs)have been considered as one of the most ideal precursor candidates of MAMs because of their tunable structure,high porosity and large specific surface area.Usually,MOF-derived MAMs exhibit excellent electrical conductivity,good magnetism and sufficient defects and interfaces,providing obvious merits in both impedance matching and microwave loss.In this review,the recent research progresses on MOF-derived MAMs were profoundly reviewed,including the categories of MOFs and MOF composites precursors,design principles,preparation methods and the relationship between mechanisms of microwave absorption and microstructures of MAMs.Finally,the current challenges and prospects for future opportunities of MOF-derived MAMs are also discussed.
基金Project supported by the National Science and Technology Major Project"Development Demonstration Engineeing of Large Low-Permability Lithologic and Stratigraphic Oil and Gas Reservoirs in the Ordos Basin"(No.2016ZX05050)the PetoChina's Science and Technology Major Project,"Study on Production Stabilization and EOR Technologics of Changqing Gas Field"(No.2016E-0509).
文摘At present,natural gas accounts for a low proportion in China's primary energy consumption structure and is highly dependent on foreign sources.Changqing gas province of the Ordos Basin where PetroChina Changqing Oilfield Company(referred to as Changqing Oilfield)is located is one of China's four major natural gas production bases.It bears the important responsibility for ensuring people's livelihood and promoting the healthy development of society economy.In recent years,Changqing Oilfield actively implements national instructive spirit on vigorously promoting domestic oil and gas exploration and development strength and formulates the secondary acceleration development strategies.Its annual natural gas production in 2020 reaches 448.5×10^(8) m^(3) and oil and gas equivalent exceeds 6000×10^(4) t,tamping its important position of“Western Daqing”in this industry.In order to further promote the continuous stable production and realize the goal of quality and efficiency improvement in Changqing gas province,this paper analyzes the situations and challenges of natural gas development in this gas province,prepares the development technological countermeasures and forecast the natural gas development prospect.And the following research results are obtained.First,the natural gas exploration and development in Changqing gas province is divided into four stages and the main technologies for the development of low-permeability carbonate gas reservoir,low-permeability sandstone gas reservoir and tight sandstone gas reservoir are formed.Second,the natural gas development in Changqing gas province faces six challenges,such as low reserve production degree,sharp decline of production rates and complex distribution of remaining undeveloped reserves of developed gas fields.And twenty-six development technological countermeasures are put forward correspondingly,such as well pattern thickening,extension and reserve increase,secondary production layer potential tapping and fine gas well management.Third,the development direction and goal of natural gas development in Changqing gas province is to pay equal attention to the stable production of old gas fields and the production increase of new areas and carry out conventional gas and unconventional gas research simultaneously.In conclusion,the annual natural gas production of Changqing gas province will maintain a sound momentum of steady growth and will exceed 500×10^(8) m^(3) at the end of the 14th Five-Year Plan and maintain at a stable level for a long term,which is conducive to the optimization of domestic energy consumption structure and realization of“carbon peak and carbon neutrality”.
基金supported by the Natural Science Foundation of Zhejiang Province(No.LHDMZ22H300003)the Science and Technology Program of Zhejiang Province(No.2019C03063),China。
文摘To overcome the pain and risk of hypoglycemia in insulin administration,glucose-responsive microneedles have been developed by researchers,which could release insulin according to the blood glucose level.We designed a kind of particles by a reversible addition-fragmentation chain transfer(RAFT)method containing a phenylboronic acid group as the sensor of glucose and carrier of insulin.poly(ethylene glycol)(PEG)-2-(dodecylthio(thiocarbonyl)thio)-2-methylpropionic acid(DDMAT)was synthesized as a macromolecular RAFT agent,which was then reacted with 3-acrylamidophenylboronic acid(AAPBA)to synthesize the block copolymer PEG-b-PAAPBA.Glucose-responsive particles loaded with insulin were prepared by self-assembly based on hydrophilic-hydrophobic interactions.Microneedle patches loaded with glucose-responsive particles were prepared using hyaluronic acid as the substrate.The insulin release behavior of the particles in glucose solutions of 0,100,and 400 mg/dL showed significant glucose responsiveness and good biosafety.The results of blood glucose control experiments in rats indicate that a single microneedle patch can effectively maintain normal blood glucose for over 7 h.
基金the Natural Science Foundation of Zhejiang Province(LHDMZ22H300003)is gratefully acknowledged.
文摘Although stimuli-responsive polymers have appeared as promising materials for drug administration,the effectiveness of these materials on various bioinspired stimuli is still open for dispute.In this work,the stimuli-responsive behaviors of radical-containing nonamphiphilic copolymers were investigated using electron paramagnetic resonance(EPR)spectroscopy while altering the pH and reductant concentration.The concentration of radicals in the aqueous solution had a considerable impact on self-assembly.The nitroxide radicals(hydrophobic)were converted to hydroxylamine(hydrophilic)when ascorbic acid(Asc)was added as a reductant,and the assemblies were switched to dissolution with a rate control behavior.The behavior of morphological change was observed in the acidic pH due to the disproportionation reaction of nitroxide radicals forming cationic species.The acquired results give new insights into the colloidal nanoparticles of nonamphiphilic copolymers and encourage the development of comparable responsive nanoparticles with intriguing drug delivery applications.
基金Financial support from the National Key Research and Development Program(2016YFB0302403)is gratefully acknowledged.
文摘The structure of polyolefin has an important influence on its performance and application.Ethylene/1-hexene copolymerization is one of the important ways to control the structure of the polyolefin.However,research on the ethylene/1-hexene copolymerization catalyzed by nickel complexes with different steric ligands remains to be refined.Here,three α-dimine nickel catalysts are used to study the ligand effect on catalytic performance in the ethylene/1-hexene copolymerization.Reaction activity,molecular weight,phase-transition temperature and branching density of the resultant copolymer are measured to evaluate the catalytic performance.The results indicate that the steric ligands could exert great effect on the copolymerization.As for the chemical valence of Ni species,detailed EPR demonstrate that the presence of excess xo-catalyst can reduce Ni(Ⅱ)to the lower valence and affect the catalytic performance.
基金funded by Yunnan Province Science and Technology Talents and Platform Plan Project(No.202305AF150067)The scientific and technological innovation team building program of Yunnan Provincial Education Department(No.K1322149)+2 种基金Yunnan Province Talent Support Program(No.CZ0096-901264)Noncommunicable Chronic DiseasesNational Science and Technology Major Project(No.2025ZD0551500,2023ZD0501500)Start-up fund of Southeast University&the China Hepatitis Prevention and Treatment Foundation Wang Baoen Liver Fibrosis Research Fund(No.2025055).
文摘Lactic acidosis is a hallmark of the tumor microenvironment(TME)and a critical impediment to the efficacy of transarterial chemoembolization(TACE)in hepatocellular carcinoma(HCC).Incomplete embolization preserves viable tumor cells that amplify hypoxia-driven glycolysis,generating a lactic acid-rich milieu that drives treatment resistance,skews immune populations toward immunosuppressive phenotypes,and impairs cytotoxic T lymphocyte function.In this review,we elucidate the pathways through which lactic acidosis compromises TACE efficacy and propose novel strategies for its mitigation.We examine emerging approaches,including systemic or intra-arterial alkalization,targeted inhibition of lactate production and export,and calcium carbonate nanoparticles,and evaluate their respective merits and limitations.Finally,we propose a combination regimen of calcium carbonate nanoparticles,lactate-targeting agents,and TACE to achieve precise drug delivery,synergistic lactic acid depletion,and enhanced antitumor immunity.These integrated strategies have the potential to convert immunologically“cold”HCC lesions into“hot”ones,thereby improving TACE outcomes and disease control.
