The cellular response to the complex extracellular microenvironment is highly dynamic in time and type of extracellular matrix.Accurately reconstructing this process and analyzing the changes in receptor conformation ...The cellular response to the complex extracellular microenvironment is highly dynamic in time and type of extracellular matrix.Accurately reconstructing this process and analyzing the changes in receptor conformation on the cell membrane surface and intracellular or intercellular signaling has been a major challenge in analytical chemistry and biophysical methodology.In this paper,a time-coded multiconcentration microfluidic chemical waveform generator was developed for the dynamic signaling probing with single-cell array of high temporal resolution,high throughput,and multi-concentration combination stimulation.Based on innovative microchannel structure,sophisticated external control methods and multiplexing technology,the system not only allowed for temporally sequential permutations of the four concentrations of stimuli(time code),but also generated pulsed and continuous waveforms at different frequencies in a highly controllable manner.Furthermore,the single-cell trap array was set up to efficiently capture cells in suspension,dramatically increasing throughput and reducing experiment preparation time.The maximum frequency of the platform was 1 Hz,and one cell could be stimulated at multiple frequencies.To show the ability of the system to investigate rapid biochemical events in high throughput,pulse stimulation and continuous stimulation of different frequencies and different time codes,combined with four concentrations of histamine(HA),were generated for probing G protein-coupled receptor(GPCR)signaling in He La cells.Then,statistical analysis was performed for the mean peak height and mean peak area of the cellular response.We believe that the time-coded multi-concentration microfluidic chemical waveform generator will provide a novel strategy for analytical chemistry,biophysics,cell signaling,and individualized medicine applications.展开更多
An analysis of the different types of interaction taking place during a video-class shows thatcommunicative methods stimulate the students’ language learning.Thus video becomes a useful languagelearning tool.
Auxetic structures exhibit an extraordinary response to mechanical forces by expanding or contracting in the transverse direction during stretching or compression,making them highly suitable for porous biomedical impl...Auxetic structures exhibit an extraordinary response to mechanical forces by expanding or contracting in the transverse direction during stretching or compression,making them highly suitable for porous biomedical implants.However,their biological functions,including nutrient transport,metabolic waste removal,and cell proliferation and differentiation,remain unexplored.This study employs computational fluid dynamics(CFD)to analyze how the auxetic deformation of a scaffold influences its biological performance.An auxetic scaffold(Ascaffold)was designed alongside a non-auxetic scaffold(N-scaffold)with identical porosity(80%)for comparison.Deformations at compressive strains of 0%,5%,and 10%were analyzed and utilized in CFD simulations to evaluate the fluid dynamics within the scaffolds.The interaction of water flow with the scaffolds was simulated,leading to predictions of mass transport and fluid flow-induced wall shear stress(WSS).Results indicated that both the fluid flow direction and scaffold architecture significantly influenced mass transport characteristics.The deformation response also impacted scaffold biological performance;specifically,the A-scaffold's concave struts hindered fluid flow in the X direction,reducing permeability but potentially promoting uniform internal fluid distribution.Although the auxetic deformation of the A-scaffold decreased its permeability,it resulted in a more irregular WSS distribution,suggesting enhanced dynamic cellular stimulation under mechanical loading.The WSSAVG of the A-scaffold and its variation during deformation were larger in the X direction than that of the Z direction.As a result,the A-scaffold exhibited better ability to transmit mechanical stimulation in the X direction.These preliminary studies numerically characterized the mass transport properties of scaffolds under auxetic deformation for the first time,provided guidance for the design and application of an auxetic scaffold.展开更多
Bone marrow-derived mesenchymal stem cell(MSC)is one of the most actively studied cell types due to its regenerative potential and immunomodulatory properties.Conventional cell expansion methods using 2D tissue cultur...Bone marrow-derived mesenchymal stem cell(MSC)is one of the most actively studied cell types due to its regenerative potential and immunomodulatory properties.Conventional cell expansion methods using 2D tissue culture plates and 2.5D microcarriers in bioreactors can generate large cell numbers,but they compromise stem cell potency and lack mechanical preconditioning to prepare MSC for physiological loading expected in vivo.To overcome these challenges,in this work,we describe a 3D dynamic hydrogel using magneto-stimulation for direct MSC manufacturing to therapy.With our technology,we found that dynamic mechanical stimulation(DMS)enhanced matrix-integrinβ1 interactions which induced MSCs spreading and proliferation.In addition,DMS could modulate MSC biofunctions including directing MSC differentiation into specific lineages and boosting paracrine activities(e.g.,growth factor secretion)through YAP nuclear localization and FAK-ERK pathway.With our magnetic hydrogel,complex procedures from MSC manufacturing to final clinical use,can be integrated into one single platform,and we believe this‘all-in-one’technology could offer a paradigm shift to existing standards in MSC therapy.展开更多
基金the National Natural Science Foundation of China(Nos.22074047,21775049 and 31700746)the Hubei Provincial Natural Science Foundation of China(No.2020CFB578)the Fundamental Research Funds for Central Universities,HUST(Nos.2020kfy XJJS034 and 2021GCRC056)。
文摘The cellular response to the complex extracellular microenvironment is highly dynamic in time and type of extracellular matrix.Accurately reconstructing this process and analyzing the changes in receptor conformation on the cell membrane surface and intracellular or intercellular signaling has been a major challenge in analytical chemistry and biophysical methodology.In this paper,a time-coded multiconcentration microfluidic chemical waveform generator was developed for the dynamic signaling probing with single-cell array of high temporal resolution,high throughput,and multi-concentration combination stimulation.Based on innovative microchannel structure,sophisticated external control methods and multiplexing technology,the system not only allowed for temporally sequential permutations of the four concentrations of stimuli(time code),but also generated pulsed and continuous waveforms at different frequencies in a highly controllable manner.Furthermore,the single-cell trap array was set up to efficiently capture cells in suspension,dramatically increasing throughput and reducing experiment preparation time.The maximum frequency of the platform was 1 Hz,and one cell could be stimulated at multiple frequencies.To show the ability of the system to investigate rapid biochemical events in high throughput,pulse stimulation and continuous stimulation of different frequencies and different time codes,combined with four concentrations of histamine(HA),were generated for probing G protein-coupled receptor(GPCR)signaling in He La cells.Then,statistical analysis was performed for the mean peak height and mean peak area of the cellular response.We believe that the time-coded multi-concentration microfluidic chemical waveform generator will provide a novel strategy for analytical chemistry,biophysics,cell signaling,and individualized medicine applications.
文摘An analysis of the different types of interaction taking place during a video-class shows thatcommunicative methods stimulate the students’ language learning.Thus video becomes a useful languagelearning tool.
基金supported by the National Natural Science Foundation of China[grant numbers 12202036,12172034,U23A2070,T2288101,12332019]the 111 project[grant number B13003]the Fundamental Research Funds for the Central Universities.
文摘Auxetic structures exhibit an extraordinary response to mechanical forces by expanding or contracting in the transverse direction during stretching or compression,making them highly suitable for porous biomedical implants.However,their biological functions,including nutrient transport,metabolic waste removal,and cell proliferation and differentiation,remain unexplored.This study employs computational fluid dynamics(CFD)to analyze how the auxetic deformation of a scaffold influences its biological performance.An auxetic scaffold(Ascaffold)was designed alongside a non-auxetic scaffold(N-scaffold)with identical porosity(80%)for comparison.Deformations at compressive strains of 0%,5%,and 10%were analyzed and utilized in CFD simulations to evaluate the fluid dynamics within the scaffolds.The interaction of water flow with the scaffolds was simulated,leading to predictions of mass transport and fluid flow-induced wall shear stress(WSS).Results indicated that both the fluid flow direction and scaffold architecture significantly influenced mass transport characteristics.The deformation response also impacted scaffold biological performance;specifically,the A-scaffold's concave struts hindered fluid flow in the X direction,reducing permeability but potentially promoting uniform internal fluid distribution.Although the auxetic deformation of the A-scaffold decreased its permeability,it resulted in a more irregular WSS distribution,suggesting enhanced dynamic cellular stimulation under mechanical loading.The WSSAVG of the A-scaffold and its variation during deformation were larger in the X direction than that of the Z direction.As a result,the A-scaffold exhibited better ability to transmit mechanical stimulation in the X direction.These preliminary studies numerically characterized the mass transport properties of scaffolds under auxetic deformation for the first time,provided guidance for the design and application of an auxetic scaffold.
基金supported by NUS Presidential Young Professorship,MOE Tier 1 grantsupported by the NUS Research Scholarship.
文摘Bone marrow-derived mesenchymal stem cell(MSC)is one of the most actively studied cell types due to its regenerative potential and immunomodulatory properties.Conventional cell expansion methods using 2D tissue culture plates and 2.5D microcarriers in bioreactors can generate large cell numbers,but they compromise stem cell potency and lack mechanical preconditioning to prepare MSC for physiological loading expected in vivo.To overcome these challenges,in this work,we describe a 3D dynamic hydrogel using magneto-stimulation for direct MSC manufacturing to therapy.With our technology,we found that dynamic mechanical stimulation(DMS)enhanced matrix-integrinβ1 interactions which induced MSCs spreading and proliferation.In addition,DMS could modulate MSC biofunctions including directing MSC differentiation into specific lineages and boosting paracrine activities(e.g.,growth factor secretion)through YAP nuclear localization and FAK-ERK pathway.With our magnetic hydrogel,complex procedures from MSC manufacturing to final clinical use,can be integrated into one single platform,and we believe this‘all-in-one’technology could offer a paradigm shift to existing standards in MSC therapy.
