This study aimed at exploring the effect of surface morphology of dense phosphate calcimn （Ca-P） ceramics upon the formation of bone-like apatite in static or dynamic simulated body fluid （SBF）. Dense and sandblas...This study aimed at exploring the effect of surface morphology of dense phosphate calcimn （Ca-P） ceramics upon the formation of bone-like apatite in static or dynamic simulated body fluid （SBF）. Dense and sandblasted calcium phosphate ceramics were immersed into dynamic SBF flowing at normal physiological speed of body fluid of skeletal muscle. The changes were characterized using SEM, XPS, IR and XRD. Changes can be observed after the sandblasted surface of dense calcium phosphate ceramics had been immersed in SBF for 14 days. XPS analysis results showed that the flake-like structure was composed of Ca, P, C, O; IR analysis result of surface structure of samples showed that there were specific peaks for CO3^2-; XRD results indicated the decrease in crystallinity and the increase in amorphous structure. The rough surface was advantageous for the formation of bone-like apatite. Increasing the Ca^2＋, HPO4^2- concentration of SBF could also enhance the bonelike apatite formation. All the results demonstrated that local concentration is a key factor affecting nucleation.展开更多
The formation pathway of colloidal semiconductor ZnSe magic-size clusters(MSCs)in a reaction that display an optical absorption doublet remains poorly understood.The reaction of Zn(OAc)_(2)/OLA(made from zinc acetate ...The formation pathway of colloidal semiconductor ZnSe magic-size clusters(MSCs)in a reaction that display an optical absorption doublet remains poorly understood.The reaction of Zn(OAc)_(2)/OLA(made from zinc acetate and oleylamine)and tri-noctylphosphine selenide(SeTOP)in OLA in the presence of diphenylphosphine(HPPh_(2))is studied,in which dMSC-345 displays a doublet peaking at 328/345 nm.We suggest that the development is from the clusters that form in the initial prenucleation stage of the reaction.The clusters are the precursor compound(PC-299)of MSC-299(displaying an absorption singlet peaking at 299 nm).PC-299 transforms to PC-345 at a later stage.The presence of alcohol(such as methanol or ethylene glycol)promotes another pathway,which is the PC-299 to PC-320 transformation.PC-320 transforms to dMSC-320(with a doublet at 305/320 nm),followed by dMSC-345 via PC-345.The present study provides additional evidence that clusters(PC-299)form and transform(such as to dMSC-345 via PC-345)in the prenucleation stage of ZnSe quantum dots(QDs).展开更多
Hydroxyapatite ceramics (HA) has been proved to be excellent in biocompatibility and bioactivity. However, limited information is available concerning how HA ceramics affects the maturation of osteoblasts in molecular...Hydroxyapatite ceramics (HA) has been proved to be excellent in biocompatibility and bioactivity. However, limited information is available concerning how HA ceramics affects the maturation of osteoblasts in molecular biological level in vitro. This study examines the mRNA expression and protein production of bone-related genes in osteoblast-like cell line (Saos-2) cultured on HA disks. Saos-2 cells are seeded onto the substrates and cultured for 18 days. Harvested cells are tested for the cell growth rate, expression of mRNAs for osteocalcin and alkaline phosphatase, and protein production of bone sialoprotein and osteocalcin. MTS assay shows that cell proliferates well on HA ceramic substrate. After 9d, bone sialoprotein and osteocalcin protein production in SaPS-2 increases more on HA surfaces than on control material. As bone sialoprotein and osteocalcin are the genes to be highly expressed at the late stage of osteoblast differentiation, this study reveals that after long time culture in HA, HA can induce Saos-2 maturation. The behavior of Saos-2 on HA surfaces revealed in this study provides valuable information for the understanding of the biocompatibility and bioactivity of HA ceramics.展开更多
In order to explore the potential application of Ramie fibre(RF)in medical dressing,the absorbency ratio of ramie fibre cloth,medical gauze and natural cotton fibre cloth was tested,and the factors affecting the absor...In order to explore the potential application of Ramie fibre(RF)in medical dressing,the absorbency ratio of ramie fibre cloth,medical gauze and natural cotton fibre cloth was tested,and the factors affecting the absorbency ratio of materials were analysed.Meanwhile,the hemocompatibility of the three fibre materials were also studied.The results showed that the RF cloth had good moisture absorption and hemocompatibility.Therefore,RF is a potential material for medical dressing.展开更多
Recent studies have shown that 3D printed scaffolds integrated with growth factors can guide the growth of neurites and promote axon regeneration at the injury site.However,heat,organic solvents or cross-linking agent...Recent studies have shown that 3D printed scaffolds integrated with growth factors can guide the growth of neurites and promote axon regeneration at the injury site.However,heat,organic solvents or cross-linking agents used in conventional 3D printing reduce the biological activity of growth factors.Low temperature 3D printing can incorporate growth factors into the scaffold and maintain their biological activity.In this study,we developed a collagen/chitosan scaffold integrated with brain-derived neurotrophic factor(3D-CC-BDNF)by low temperature extrusion 3D printing as a new type of artificial controlled release system,which could prolong the release of BDNF for the treatment of spinal cord injury(SCI).Eight weeks after the implantation of scaffolds in the transected lesion of T10 of the spinal cord,3D-CC-BDNF significantly ameliorate locomotor function of the rats.Consistent with the recovery of locomotor function,3D-CC-BDNF treatment could fill the gap,facilitate nerve fiber regeneration,accelerate the establishment of synaptic connections and enhance remyelination at the injury site.展开更多
We report,for the first time,the synthesis of CdS magic-size clusters (MSCs) which exhibit a single sharp absorption peaking at ~ 361 nm,along with sharp band edge photoemission at ~ 377 nm and broad trap emission pea...We report,for the first time,the synthesis of CdS magic-size clusters (MSCs) which exhibit a single sharp absorption peaking at ~ 361 nm,along with sharp band edge photoemission at ~ 377 nm and broad trap emission peaking at ~ 490 nm.These MSCs are produced in a singleensemble form without the contamination of conventional quantum dots (QDs) and/or other-bandgap clusters.They are denoted as MSC-361.We present the details of several controlled syntheses done in oleylamine (OLA),using C,d(NO3)2 or C,d(OAc)2 as a C,d source and thioacetamide (TAA) or elementary sulfur (S) as a S source.A high synthetic reproducibility of the reaction of Cd(NO3)2 and TAA to single-ensemble MSC-361 is achieved,the product of which is not contaminated by other bandgap clusters and/or QDs.In some cases,the reaction product exhibits an additional absorption peak at ~ 322 nm.We demonstrate that the two peaks,at 361 and 322 nm,do not evolve synchronously.Therefore,the 322 nm peak is not a higher order electronic transition of MSC-361,but due to the presence of another ensemble,namely MSC-322.The present study suggests that there is an outstanding need for the development of a physical model to narrow the knowledge gap regarding the electronic structure in these colloidal semiconductor CdS MSCs.展开更多
Little is known about how to precisely promote the selective production of either colloidal semiconductor metal chalcogenide(ME),magic-size clusters(MSCs),or quantum dots(QDs).Recently,a two-pathway model has been pro...Little is known about how to precisely promote the selective production of either colloidal semiconductor metal chalcogenide(ME),magic-size clusters(MSCs),or quantum dots(QDs).Recently,a two-pathway model has been proposed to comprehend their evolution;here,we reveal for the first time that the size of precursors plays a decisive role in the selected evolution pathway of MSCs and QDs.With the reaction of cadmium myristate(Cd(MA)2)and tri-n-octylphosphine selenide(SeTOP)in 1-octadecene(ODE)as a model system,the size of Cd precursors was manipulated by the steric hindrance of carboxylic acid(RCOOH)additive.Without RCOOH,the reaction produced both CdSe MSCs and QDs(from 100 to 240℃).With RCOOH,the reaction produced MSCs or QDs when R was small(such as CH3−)or large(such as C6H5−),respectively.According to the twopathway model,the selective evolution is attributed to the promotion and suppression of the self-assembly of Cd and Se precursors,respectively.We propose that the addition of carboxylic acid may occur ligand exchange with Cd(MA)2,causing the different sizes of Cd precursor.The results suggest that the size of Cd precursors regulates the self-assemble behavior of the precursors,which dictates the directed evolution of either MSCs or QDs.The present findings bring insights into the two-pathway model,as the size of M and E precursors determine the evolution pathways of MSCs or QDs,the understanding of which is of great fundamental significance toward mechanism-enabled design and predictive synthesis of functional nanomaterials.展开更多
Relapse and metastasis of tumor may occur for osteosarcoma(OS)patients after clinical resection.Conventional metallic scaffolds provide sufficient mechanical support to the defected bone but fail to eradicate recurrin...Relapse and metastasis of tumor may occur for osteosarcoma(OS)patients after clinical resection.Conventional metallic scaffolds provide sufficient mechanical support to the defected bone but fail to eradicate recurring tumors.Here we report that biodegradable magnesium(Mg)wirebased implant can inhibit OS growth.In brief,the Mg wires release Mg ions to activate the transport of zinc finger protein Snail1 from cytoplasm to cell nucleus,which induces apoptosis and inhibits proliferation of OS cells through a parallel antitumor signaling pathway of miRNA-181d-5p/TIMP3 and miRNA-181c-5p/NLK downstream.Simultaneously,the hydrogen gas evolution from Mg wires eliminates intracellular excessive reactive oxygen species,by which the growth of bone tumor cells is suppressed.The subcutaneous tumor-bearing experiment of OS cells in nude mice further confirms that Mg wires can effectively inhibit the growth of tumors and prolong the survival of tumor-bearing mice.In addition,Mg wires have no toxicity to normal cells and tissues.These results suggest that Mg implant is a potential anti-tumor scaffold for OS patients.展开更多
In order to endow titanium metals with bioactivity and antimicrobial properties, titanium plates were subjected to anodic oxidation treatment in NaCl solutions in this study. The treated titanium metals could induce a...In order to endow titanium metals with bioactivity and antimicrobial properties, titanium plates were subjected to anodic oxidation treatment in NaCl solutions in this study. The treated titanium metals could induce apatite formation in the fast calcification solution, and osteoblasts on the treated titanium surfaces proliferated well as those on the untreated titanium metal surfaces. The treated metals could inhibit S. aureus growth in the microbial culture experiments. It was assumed that Ti-OH groups and Ti-Cl groups formed on the treated titanium surface were responsible for the bioactivity and antimicrobial properties of the metals. The anodic oxidation treatment was an effective way to prepare bioactive titanium surfaces with antimicrobial properties.展开更多
The formation pathway of aqueous-phase colloidal semiconductor magic-size clusters(MSCs)remains unrevealed.In the present work,we demonstrate,for the first time,a precursor compound(PC)-enabled formation pathway of aq...The formation pathway of aqueous-phase colloidal semiconductor magic-size clusters(MSCs)remains unrevealed.In the present work,we demonstrate,for the first time,a precursor compound(PC)-enabled formation pathway of aqueous-phase CdSe MSCs exhibiting a sharp absorption peaking at about 420 nm(MSC-420).The CdSe MSC-420 is synthesized with CdCl2 and selenourea as the respective Cd and Se sources,and with 3-mercaptopropionic acid or L-cysteine as a ligand.Absorption featureless CdSe PCs form first in the aqueous reaction batches,which transform to MSC-420 in the presence of primary amines.The coordination between primary amine and Cd^(2+)on PCs may be responsible to the PC-to-MSC transformation.Upon increasing the reactant concentrations or decreasing the CdCl_(2)-ligand feed molar ratios,the Cd precursor self-assembles into large aggregates,which may encapsulate the resulting CdSe PCs and inhibit their transformation to MSC-420.The present study sheds essential light on the syntheses and formation mechanisms of nanocrystals.展开更多
The regulation of macrophage phenotype(M1/M2)is very important for tissue repair.The macrophage phenotypes could be affected by the physical and chemical parameters of implant surface.The aim of this study was to inve...The regulation of macrophage phenotype(M1/M2)is very important for tissue repair.The macrophage phenotypes could be affected by the physical and chemical parameters of implant surface.The aim of this study was to investigate the effects of surface modifications of titanium metals on macrophage phenotype.The medical pure titanium metals(PT-Ti)subjected to Anodic Oxidation(AO-Ti),Sand Blasting/acid etching(SLA-Ti)and Plasma-sprayed HA coating(HA coating-Ti)were used for regulating the phenotype of macrophage.The results showed that the Raw264.7 cells of AO-Ti groups had no obvious pseudopodia and could spread evenly in all directions.The levels of IL-1βand TNF-α,which belong to pro-inflammatory genes,expressed by the cells on AO-Ti groups were the lowest among all of the modified titanium groups.But,the levels of IL-10 and TGF-β,which belong to anti-inflammatory genes,expressed on AO-Ti groups were much higher than those on the other groups.Furthermore,the AO-Ti could regulate the expression of SOCS-1 and SOCS-3 to affect the active of NF-κB signaling.The gene expression results of macrophages showed that the AO-Ti was more conductive to inhibit the expression of M1-related genes and promote the expression of M2-related genes in an inflammatory environment.The AO-Ti was more beneficial to tissue repair than other modified titanium metals.The results showed that the anodic oxidation is an effective method to regulate the phenotype of macrophages.展开更多
Precursor compounds(PCs)link quantum dots(QDs)and magic-sized clusters(MSCs),which is pivotal in the conversion between QDs and MSCs.Here,for the first time,we report the transformation,synthesis,and composition of a ...Precursor compounds(PCs)link quantum dots(QDs)and magic-sized clusters(MSCs),which is pivotal in the conversion between QDs and MSCs.Here,for the first time,we report the transformation,synthesis,and composition of a type of ZnSe PCs.ZnSe PCs can be directly transformed to two different MSCs with the assistance of octylamine and acetic acid at room temperature.The two types of MSCs exhibit sharp absorption peaks at 299 and 328 nm which are denoted as MSC-299 and MSC-328.In the preparation of ZnSe PCs,diphenylphosphine(DPP)as an additive plays a key role which not only inhibits the thermal decomposition of Zn precursor,but also acts as a reducing agent to reduce the by-products produced in the reaction.The composition was explored by X-ray photoelectron spectroscopy,energy dispersive spectrometer,matrix-assisted laser desorption/ionization time-of-flight mass spectra with ZnSe PC powder appeared as white powder after purifying by toluene(Tol)and methanol(MeOH).The results indicate that the molar ratio of Zn/Se is 2:1 with a molecular of〜3,350 Da.Therefore,we propose that the molecular formula of ZnSe PCs is Zn_(32)Se_(16).In addition,at the molecular level,the covalent bond of Zn-Se is formed in ZnSe PCs.This study offers a deeper understanding of the transformation from PCs to MSCs and for the first time proposes the composition of PCs.Meanwhile,this research provides us with a new understanding of the role of DPP in the synthesis of colloidal semiconductor nanoparticles.展开更多
文摘This study aimed at exploring the effect of surface morphology of dense phosphate calcimn （Ca-P） ceramics upon the formation of bone-like apatite in static or dynamic simulated body fluid （SBF）. Dense and sandblasted calcium phosphate ceramics were immersed into dynamic SBF flowing at normal physiological speed of body fluid of skeletal muscle. The changes were characterized using SEM, XPS, IR and XRD. Changes can be observed after the sandblasted surface of dense calcium phosphate ceramics had been immersed in SBF for 14 days. XPS analysis results showed that the flake-like structure was composed of Ca, P, C, O; IR analysis result of surface structure of samples showed that there were specific peaks for CO3^2-; XRD results indicated the decrease in crystallinity and the increase in amorphous structure. The rough surface was advantageous for the formation of bone-like apatite. Increasing the Ca^2＋, HPO4^2- concentration of SBF could also enhance the bonelike apatite formation. All the results demonstrated that local concentration is a key factor affecting nucleation.
基金the National Natural Science Foundation of China(No.22275126)the Natural Science Foundation of Sichuan Province(No.2023NSFSC0634)+1 种基金the Open Project of Key State Laboratory for Supramolecular Structures and Materials of Jilin University(No.SKLSSM 2023031)the National Natural Science Foundation of China(No.22305162).
文摘The formation pathway of colloidal semiconductor ZnSe magic-size clusters(MSCs)in a reaction that display an optical absorption doublet remains poorly understood.The reaction of Zn(OAc)_(2)/OLA(made from zinc acetate and oleylamine)and tri-noctylphosphine selenide(SeTOP)in OLA in the presence of diphenylphosphine(HPPh_(2))is studied,in which dMSC-345 displays a doublet peaking at 328/345 nm.We suggest that the development is from the clusters that form in the initial prenucleation stage of the reaction.The clusters are the precursor compound(PC-299)of MSC-299(displaying an absorption singlet peaking at 299 nm).PC-299 transforms to PC-345 at a later stage.The presence of alcohol(such as methanol or ethylene glycol)promotes another pathway,which is the PC-299 to PC-320 transformation.PC-320 transforms to dMSC-320(with a doublet at 305/320 nm),followed by dMSC-345 via PC-345.The present study provides additional evidence that clusters(PC-299)form and transform(such as to dMSC-345 via PC-345)in the prenucleation stage of ZnSe quantum dots(QDs).
文摘Hydroxyapatite ceramics (HA) has been proved to be excellent in biocompatibility and bioactivity. However, limited information is available concerning how HA ceramics affects the maturation of osteoblasts in molecular biological level in vitro. This study examines the mRNA expression and protein production of bone-related genes in osteoblast-like cell line (Saos-2) cultured on HA disks. Saos-2 cells are seeded onto the substrates and cultured for 18 days. Harvested cells are tested for the cell growth rate, expression of mRNAs for osteocalcin and alkaline phosphatase, and protein production of bone sialoprotein and osteocalcin. MTS assay shows that cell proliferates well on HA ceramic substrate. After 9d, bone sialoprotein and osteocalcin protein production in SaPS-2 increases more on HA surfaces than on control material. As bone sialoprotein and osteocalcin are the genes to be highly expressed at the late stage of osteoblast differentiation, this study reveals that after long time culture in HA, HA can induce Saos-2 maturation. The behavior of Saos-2 on HA surfaces revealed in this study provides valuable information for the understanding of the biocompatibility and bioactivity of HA ceramics.
基金National Nature Science Foundation of China,Grant/Award Numbers:31771035,32071325Cooperation program of Sichuan University and Panzhihua City,Grant/Award Number:2018CDPZH-15National Key Program for Research and Development of China,Grant/Award Number:2016YFC1102703。
文摘In order to explore the potential application of Ramie fibre(RF)in medical dressing,the absorbency ratio of ramie fibre cloth,medical gauze and natural cotton fibre cloth was tested,and the factors affecting the absorbency ratio of materials were analysed.Meanwhile,the hemocompatibility of the three fibre materials were also studied.The results showed that the RF cloth had good moisture absorption and hemocompatibility.Therefore,RF is a potential material for medical dressing.
基金supported by the National Nature Scientific Fund of China(81771352,81971782,81771350)the Nature Scientific Fund of Tianjin(18JCJQJC48500,19JCYBJC27900).
文摘Recent studies have shown that 3D printed scaffolds integrated with growth factors can guide the growth of neurites and promote axon regeneration at the injury site.However,heat,organic solvents or cross-linking agents used in conventional 3D printing reduce the biological activity of growth factors.Low temperature 3D printing can incorporate growth factors into the scaffold and maintain their biological activity.In this study,we developed a collagen/chitosan scaffold integrated with brain-derived neurotrophic factor(3D-CC-BDNF)by low temperature extrusion 3D printing as a new type of artificial controlled release system,which could prolong the release of BDNF for the treatment of spinal cord injury(SCI).Eight weeks after the implantation of scaffolds in the transected lesion of T10 of the spinal cord,3D-CC-BDNF significantly ameliorate locomotor function of the rats.Consistent with the recovery of locomotor function,3D-CC-BDNF treatment could fill the gap,facilitate nerve fiber regeneration,accelerate the establishment of synaptic connections and enhance remyelination at the injury site.
基金the National Natural Science Foundation of China(Nos.21773162 and 21573155)the Fundamental Research Funds for the Central Universities (No.SCU2015A002)+1 种基金the State Key Laboratory of Polymer Materials Engineering of Sichuan University (No.sklpme2018-2-08)the Open Project of Key State Laboratory for Supramolecular Structures and Materials of Jilin University for SKLSSM 201830.H.F.and W.H.thank the National Major Scientific and Technological Special Project for "Significant New Drugs Development”(Nos.2018ZX09201009-005-004 and 2018ZX09201009-005-001).We thank Sichuan Univ of Analytical & Testing Center.We are in debt to Du Shanling Wang (Analytical & Testing Center,Sichuan University) for TEM.
文摘We report,for the first time,the synthesis of CdS magic-size clusters (MSCs) which exhibit a single sharp absorption peaking at ~ 361 nm,along with sharp band edge photoemission at ~ 377 nm and broad trap emission peaking at ~ 490 nm.These MSCs are produced in a singleensemble form without the contamination of conventional quantum dots (QDs) and/or other-bandgap clusters.They are denoted as MSC-361.We present the details of several controlled syntheses done in oleylamine (OLA),using C,d(NO3)2 or C,d(OAc)2 as a C,d source and thioacetamide (TAA) or elementary sulfur (S) as a S source.A high synthetic reproducibility of the reaction of Cd(NO3)2 and TAA to single-ensemble MSC-361 is achieved,the product of which is not contaminated by other bandgap clusters and/or QDs.In some cases,the reaction product exhibits an additional absorption peak at ~ 322 nm.We demonstrate that the two peaks,at 361 and 322 nm,do not evolve synchronously.Therefore,the 322 nm peak is not a higher order electronic transition of MSC-361,but due to the presence of another ensemble,namely MSC-322.The present study suggests that there is an outstanding need for the development of a physical model to narrow the knowledge gap regarding the electronic structure in these colloidal semiconductor CdS MSCs.
基金K.Y.thanks the National Natural Science Foundation of China(NSFC,No.21773162)the Fundamental Research Funds for the Central Universities,the Applied Basic Research Programs of Science and Technology Department of Sichuan Province(No,2020YJ0326)+3 种基金the State Key Laboratory of Polymer Materials Engineering of Sichuan University respectively for No.sklpme2020-2-09,and the Open Project of Key State Laboratory for Supramolecular Structures and Materials of Jilin University for No.SKLSSM 2021030M.Z.is grateful to National Natural Science Foundation of China((NSFC,No.22002099)China Postdoctoral Science Foundation(No.2020T130441)Sichuan University postdoctoral interdisciplinary Innovation Fund and the Open Project of Key State Laboratory for Supramolecular Structures and Materials of Jilin University(No.SKLSSM 2021032)C.R.L.is grateful to the COVID-19 Science and Technology Emergency Project of Sichuan Province of China(No.2021YFS0408).
文摘Little is known about how to precisely promote the selective production of either colloidal semiconductor metal chalcogenide(ME),magic-size clusters(MSCs),or quantum dots(QDs).Recently,a two-pathway model has been proposed to comprehend their evolution;here,we reveal for the first time that the size of precursors plays a decisive role in the selected evolution pathway of MSCs and QDs.With the reaction of cadmium myristate(Cd(MA)2)and tri-n-octylphosphine selenide(SeTOP)in 1-octadecene(ODE)as a model system,the size of Cd precursors was manipulated by the steric hindrance of carboxylic acid(RCOOH)additive.Without RCOOH,the reaction produced both CdSe MSCs and QDs(from 100 to 240℃).With RCOOH,the reaction produced MSCs or QDs when R was small(such as CH3−)or large(such as C6H5−),respectively.According to the twopathway model,the selective evolution is attributed to the promotion and suppression of the self-assembly of Cd and Se precursors,respectively.We propose that the addition of carboxylic acid may occur ligand exchange with Cd(MA)2,causing the different sizes of Cd precursor.The results suggest that the size of Cd precursors regulates the self-assemble behavior of the precursors,which dictates the directed evolution of either MSCs or QDs.The present findings bring insights into the two-pathway model,as the size of M and E precursors determine the evolution pathways of MSCs or QDs,the understanding of which is of great fundamental significance toward mechanism-enabled design and predictive synthesis of functional nanomaterials.
基金the National Key Research and Development Program of China(2018YFC1106600)the Interdisciplinary Program of Shanghai Jiao Tong University(ZH2018QNB07)。
文摘Relapse and metastasis of tumor may occur for osteosarcoma(OS)patients after clinical resection.Conventional metallic scaffolds provide sufficient mechanical support to the defected bone but fail to eradicate recurring tumors.Here we report that biodegradable magnesium(Mg)wirebased implant can inhibit OS growth.In brief,the Mg wires release Mg ions to activate the transport of zinc finger protein Snail1 from cytoplasm to cell nucleus,which induces apoptosis and inhibits proliferation of OS cells through a parallel antitumor signaling pathway of miRNA-181d-5p/TIMP3 and miRNA-181c-5p/NLK downstream.Simultaneously,the hydrogen gas evolution from Mg wires eliminates intracellular excessive reactive oxygen species,by which the growth of bone tumor cells is suppressed.The subcutaneous tumor-bearing experiment of OS cells in nude mice further confirms that Mg wires can effectively inhibit the growth of tumors and prolong the survival of tumor-bearing mice.In addition,Mg wires have no toxicity to normal cells and tissues.These results suggest that Mg implant is a potential anti-tumor scaffold for OS patients.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 50672062 and 30870615)Key Programs for Science and Technology Development of Sichuan Province, China (Grant No. 2008SZ0104)Sichuan Youth Science & Technology Foundation, China (Grant No. 09ZQ026-033)
文摘In order to endow titanium metals with bioactivity and antimicrobial properties, titanium plates were subjected to anodic oxidation treatment in NaCl solutions in this study. The treated titanium metals could induce apatite formation in the fast calcification solution, and osteoblasts on the treated titanium surfaces proliferated well as those on the untreated titanium metal surfaces. The treated metals could inhibit S. aureus growth in the microbial culture experiments. It was assumed that Ti-OH groups and Ti-Cl groups formed on the treated titanium surface were responsible for the bioactivity and antimicrobial properties of the metals. The anodic oxidation treatment was an effective way to prepare bioactive titanium surfaces with antimicrobial properties.
基金K.Y.thanks the National Natural Science Foundation of China(No.21773162)the Fundamental Research Funds for the Central Universities,the Applied Basic Research Programs of Science and Technology Department of Sichuan Province(No.2020YJ0326)+5 种基金the State Key Laboratory of Polymer Materials Engineering of Sichuan University(No.sklpme2020-2-09)the Open Project of Key State Laboratory for Supramolecular Structures and Materials of Jilin University(No.SKLSSM 2021030)the National Major Scientific and Technological Special Project for“Significant New Drugs Development”(No.2019ZX09201005-005-002)M.Z.is grateful to the National Natural Science Foundation of China(No.22002099)China Postdoctoral Science Foundation(No.2020T130441)Sichuan University postdoctoral interdisciplinary Innovation Fund,and the Open Project of Key State Laboratory for Supramolecular Structures and Materials of Jilin University(No.SKLSSM 2021032).
文摘The formation pathway of aqueous-phase colloidal semiconductor magic-size clusters(MSCs)remains unrevealed.In the present work,we demonstrate,for the first time,a precursor compound(PC)-enabled formation pathway of aqueous-phase CdSe MSCs exhibiting a sharp absorption peaking at about 420 nm(MSC-420).The CdSe MSC-420 is synthesized with CdCl2 and selenourea as the respective Cd and Se sources,and with 3-mercaptopropionic acid or L-cysteine as a ligand.Absorption featureless CdSe PCs form first in the aqueous reaction batches,which transform to MSC-420 in the presence of primary amines.The coordination between primary amine and Cd^(2+)on PCs may be responsible to the PC-to-MSC transformation.Upon increasing the reactant concentrations or decreasing the CdCl_(2)-ligand feed molar ratios,the Cd precursor self-assembles into large aggregates,which may encapsulate the resulting CdSe PCs and inhibit their transformation to MSC-420.The present study sheds essential light on the syntheses and formation mechanisms of nanocrystals.
基金National Key Program for Research and Development of China(No.2016YFC1102700)National Nature Science Foundation of China(Nos.31570966,31771035,32071325)+2 种基金Key Program of Science&Technology Development of Chengdu,China(No.2015-HM01-00142-SF)Jiangsu Collaborative Innovation Center of Biomedical Functional Materials,ChinaCooperation program of Sichuan University and Panzhihua City,China(No.2018CDPZH-15).
文摘The regulation of macrophage phenotype(M1/M2)is very important for tissue repair.The macrophage phenotypes could be affected by the physical and chemical parameters of implant surface.The aim of this study was to investigate the effects of surface modifications of titanium metals on macrophage phenotype.The medical pure titanium metals(PT-Ti)subjected to Anodic Oxidation(AO-Ti),Sand Blasting/acid etching(SLA-Ti)and Plasma-sprayed HA coating(HA coating-Ti)were used for regulating the phenotype of macrophage.The results showed that the Raw264.7 cells of AO-Ti groups had no obvious pseudopodia and could spread evenly in all directions.The levels of IL-1βand TNF-α,which belong to pro-inflammatory genes,expressed by the cells on AO-Ti groups were the lowest among all of the modified titanium groups.But,the levels of IL-10 and TGF-β,which belong to anti-inflammatory genes,expressed on AO-Ti groups were much higher than those on the other groups.Furthermore,the AO-Ti could regulate the expression of SOCS-1 and SOCS-3 to affect the active of NF-κB signaling.The gene expression results of macrophages showed that the AO-Ti was more conductive to inhibit the expression of M1-related genes and promote the expression of M2-related genes in an inflammatory environment.The AO-Ti was more beneficial to tissue repair than other modified titanium metals.The results showed that the anodic oxidation is an effective method to regulate the phenotype of macrophages.
基金the National Natural Science Foundation of China(NSFC)(No.21773162)the Applied Basic Research Programs of Science and Technology Department of Sichuan Province(No.2020YJ0326)+1 种基金the State Key Laboratory of Supramolecular Structures and Materials of Jilin University(SKLSSM 202035)M.Z.is grateful to Sichuan University Postdoctoral Research Fund(No.2019SCU12073)and the Fundamental Research Funds for the Central Universities.
文摘Precursor compounds(PCs)link quantum dots(QDs)and magic-sized clusters(MSCs),which is pivotal in the conversion between QDs and MSCs.Here,for the first time,we report the transformation,synthesis,and composition of a type of ZnSe PCs.ZnSe PCs can be directly transformed to two different MSCs with the assistance of octylamine and acetic acid at room temperature.The two types of MSCs exhibit sharp absorption peaks at 299 and 328 nm which are denoted as MSC-299 and MSC-328.In the preparation of ZnSe PCs,diphenylphosphine(DPP)as an additive plays a key role which not only inhibits the thermal decomposition of Zn precursor,but also acts as a reducing agent to reduce the by-products produced in the reaction.The composition was explored by X-ray photoelectron spectroscopy,energy dispersive spectrometer,matrix-assisted laser desorption/ionization time-of-flight mass spectra with ZnSe PC powder appeared as white powder after purifying by toluene(Tol)and methanol(MeOH).The results indicate that the molar ratio of Zn/Se is 2:1 with a molecular of〜3,350 Da.Therefore,we propose that the molecular formula of ZnSe PCs is Zn_(32)Se_(16).In addition,at the molecular level,the covalent bond of Zn-Se is formed in ZnSe PCs.This study offers a deeper understanding of the transformation from PCs to MSCs and for the first time proposes the composition of PCs.Meanwhile,this research provides us with a new understanding of the role of DPP in the synthesis of colloidal semiconductor nanoparticles.
