Exosomes,ubiquitously present in body fluids,serve as non-invasive biomarkers for disease diagnosis,monitoring,and treatment.As intercellular messengers,exosomes encapsulate a rich array of proteins,nucleic acids,and ...Exosomes,ubiquitously present in body fluids,serve as non-invasive biomarkers for disease diagnosis,monitoring,and treatment.As intercellular messengers,exosomes encapsulate a rich array of proteins,nucleic acids,and metabolites,although most studies have primarily focused on proteins and RNA.Recently,exosome metabolomics has demonstrated clinical value and potential advantages in disease detection and pathophysiology,despite significant challenges,particularly in exosome isolation and metabolite detection.This review discusses the significant technical challenges in exosome isolation and metabolite detection,highlighting the advancements in these areas that support the clinical application of exosome metabolomics,and illustrates the potential of exosomal metabolites from various body fluids as biomarkers for early disease diagnosis and treatment.展开更多
Fatigue and tensile behaviors of homogenized WE 54 magnesium alloy before and after immersion in simulated body fluid(SBF)were investigated.According to the tensile test,the alloy without immersion in SBF solution has...Fatigue and tensile behaviors of homogenized WE 54 magnesium alloy before and after immersion in simulated body fluid(SBF)were investigated.According to the tensile test,the alloy without immersion in SBF solution has the highest tensile strength of 278 MPa,which decreased to 190 MPa after 336 h of immersion..The fatigue life of the homogenized WE 54 magnesium alloy before immersion in the SBF solution under a constant stress of 15 MPa is 3598 cycles.However,the fatigue life of the alloy decreased to 453 cycles after 336 h of immersion in the SBF solution under the same stress.Examination of the fracture surface of the samples by SEM reveals that the origin of the fatigue crack before immersion is micro-pores and defects.While corrosion pits and cracks are the main reasons for forming the initial fatigue crack after immersion.Moreover,the results obtained from practical work were evaluated and compared to theoretical calculations.The area of the hysteresis loops of the samples after the fatigue test,determined using Triangles and Monte Carlo methods,decreased from 4954.5 MPa and 4842.9 MPa before immersion to 192.0 MPa and 175.8 MPa after 336 h of immersion,respectively.展开更多
Porous and dense TiNi alloys were successfully fabricated by powder metallurgy(P/M) method, and to further improve their surface biocompatibility, surface modification techniques including grind using silicon-carbide(...Porous and dense TiNi alloys were successfully fabricated by powder metallurgy(P/M) method, and to further improve their surface biocompatibility, surface modification techniques including grind using silicon-carbide(SiC) paper, acid etching and alkali treatment were employed to produce either irregularly rough surface or micro-porous surface roughness. X-ray diffractometry(XRD), scanning electron microscopy(SEM) and energy dispersive X-ray spectroscopy(EDX) attached to SEM were used to characterize surface structure and the Ca-P coatings. Effects of the above surface treatments on the surface morphology, apatite forming ability were systematically investigated. Results indicate that all the above surface treatments increase the apatite forming ability of TiNi alloys in varying degrees when soaked in simulated body fluid(SBF). More apatite coatings formed on TiNi samples sintered at 1050℃ and 1100℃ due to their high porosity and pure TiNi phase that is beneficial to heterogeneous nucleation. Furthermore, more uniform apatite was fabricated on the sample sintered from the mixture of Ni and Ti powders.展开更多
FeCrAl(f)/HA biological functionally gradient materials(FGMs) were successfully fabricated by the hot pressing technique.Scanning electron microscope(SEM),energy dispersive spectrometer(EDS) and bending strength test ...FeCrAl(f)/HA biological functionally gradient materials(FGMs) were successfully fabricated by the hot pressing technique.Scanning electron microscope(SEM),energy dispersive spectrometer(EDS) and bending strength test machine were utilized to characterize the microstructure,component,mechanical properties and the formation of the Ca-deficient apatite on the surface of these materials.The results indicate that an asymmetrical FeCrAl(f)/HA FGM,consolidating powders prepared by mixing HA with 3%–15%(volume fraction) is successfully prepared.Both of the matrix and FeCrAl fiber are integrated very tightly and bite into each other very deeply.And counter diffusion takes place to some extent in two phase interfaces.The elemental compositions of the FeCrAl(f)/HA FGM change progressively.Ca and P contents increase gradually with immersion time increasing,and thereafter approach equilibrium.The bone-like apatite layer forms on the materials surface,which possesses benign bioactivity,and the favorable biocompatibility can provide potential firm fixation between FeCrAl(f)/HA asymmetrical FGM implants and human bone.展开更多
文摘Exosomes,ubiquitously present in body fluids,serve as non-invasive biomarkers for disease diagnosis,monitoring,and treatment.As intercellular messengers,exosomes encapsulate a rich array of proteins,nucleic acids,and metabolites,although most studies have primarily focused on proteins and RNA.Recently,exosome metabolomics has demonstrated clinical value and potential advantages in disease detection and pathophysiology,despite significant challenges,particularly in exosome isolation and metabolite detection.This review discusses the significant technical challenges in exosome isolation and metabolite detection,highlighting the advancements in these areas that support the clinical application of exosome metabolomics,and illustrates the potential of exosomal metabolites from various body fluids as biomarkers for early disease diagnosis and treatment.
文摘Fatigue and tensile behaviors of homogenized WE 54 magnesium alloy before and after immersion in simulated body fluid(SBF)were investigated.According to the tensile test,the alloy without immersion in SBF solution has the highest tensile strength of 278 MPa,which decreased to 190 MPa after 336 h of immersion..The fatigue life of the homogenized WE 54 magnesium alloy before immersion in the SBF solution under a constant stress of 15 MPa is 3598 cycles.However,the fatigue life of the alloy decreased to 453 cycles after 336 h of immersion in the SBF solution under the same stress.Examination of the fracture surface of the samples by SEM reveals that the origin of the fatigue crack before immersion is micro-pores and defects.While corrosion pits and cracks are the main reasons for forming the initial fatigue crack after immersion.Moreover,the results obtained from practical work were evaluated and compared to theoretical calculations.The area of the hysteresis loops of the samples after the fatigue test,determined using Triangles and Monte Carlo methods,decreased from 4954.5 MPa and 4842.9 MPa before immersion to 192.0 MPa and 175.8 MPa after 336 h of immersion,respectively.
基金Project(51274247) supported by the National Natural Science Foundation of ChinaProject(2014zzts177) support by the Fundamental Research Funds for the Central Universities,China
文摘Porous and dense TiNi alloys were successfully fabricated by powder metallurgy(P/M) method, and to further improve their surface biocompatibility, surface modification techniques including grind using silicon-carbide(SiC) paper, acid etching and alkali treatment were employed to produce either irregularly rough surface or micro-porous surface roughness. X-ray diffractometry(XRD), scanning electron microscopy(SEM) and energy dispersive X-ray spectroscopy(EDX) attached to SEM were used to characterize surface structure and the Ca-P coatings. Effects of the above surface treatments on the surface morphology, apatite forming ability were systematically investigated. Results indicate that all the above surface treatments increase the apatite forming ability of TiNi alloys in varying degrees when soaked in simulated body fluid(SBF). More apatite coatings formed on TiNi samples sintered at 1050℃ and 1100℃ due to their high porosity and pure TiNi phase that is beneficial to heterogeneous nucleation. Furthermore, more uniform apatite was fabricated on the sample sintered from the mixture of Ni and Ti powders.
基金Project(51274247)supported by the National Natural Science Foundation of ChinaProject(2012BAE06B00)supported by the National High Technology Research and Development Program to China+1 种基金Project(2011QNZT046)supported by the Fundamental Research Funds of Central South Universities of ChinaProject supported by Hunan Postdoctoral Scientific Program,China
文摘FeCrAl(f)/HA biological functionally gradient materials(FGMs) were successfully fabricated by the hot pressing technique.Scanning electron microscope(SEM),energy dispersive spectrometer(EDS) and bending strength test machine were utilized to characterize the microstructure,component,mechanical properties and the formation of the Ca-deficient apatite on the surface of these materials.The results indicate that an asymmetrical FeCrAl(f)/HA FGM,consolidating powders prepared by mixing HA with 3%–15%(volume fraction) is successfully prepared.Both of the matrix and FeCrAl fiber are integrated very tightly and bite into each other very deeply.And counter diffusion takes place to some extent in two phase interfaces.The elemental compositions of the FeCrAl(f)/HA FGM change progressively.Ca and P contents increase gradually with immersion time increasing,and thereafter approach equilibrium.The bone-like apatite layer forms on the materials surface,which possesses benign bioactivity,and the favorable biocompatibility can provide potential firm fixation between FeCrAl(f)/HA asymmetrical FGM implants and human bone.