This paper presents a fully integrated platform that leverages hardware,software,and specially formulated O/W emulsions to provide localized mechanical stimuli for manipulating cellular behaviors.The system comprises ...This paper presents a fully integrated platform that leverages hardware,software,and specially formulated O/W emulsions to provide localized mechanical stimuli for manipulating cellular behaviors.The system comprises a hexapole magnetic tweezer device,position-based current calculation software,and biocompatible micro-robots embedded with magnetic microbeads for vibration-driven force generation.High-permeability materials in the tweezer tips,combined with fast-response current regulators,enable rapid and precise force control,ensuring uniform and continuous mechanical stimuli in the pico-newton range.Closed-loop control algorithms automatically adjust coil currents based on the micro-robot’s position,thereby compensating for potential hysteresis and optimizing system stability.Experimental results demonstrate stable operation at frequencies up to 4 Hz,with a theoretical possibility of extending to 8 Hz under a 2 A current,delivering mean forces around 20 pN at 1 Hz with a 57μm emulsion.Additionally,the platform allows fine-tuning of forces by altering emulsion size or bead concentrations,thereby providing researchers with a versatile approach to study apoptosis,proliferation,and the other mechanotransduction pathways.The biodegradable and cell-friendly emulsion serves as a protective membrane for the magnetic microbeads while effectively mimicking the mechanical properties of living cells.By bridging the gap between precise motion control and continuous vibrational force application,this novel platform offers a promising tool for advancing targeted cellular studies,fostering insights into tissue engineering,and improving cancer therapies.展开更多
The periodontal ligament(PDL)plays a crucial role in transmitting and dispersing occlusal force,acting as mechanoreceptor for muscle activity during chewing,as well as mediating orthodontic tooth movement.It transform...The periodontal ligament(PDL)plays a crucial role in transmitting and dispersing occlusal force,acting as mechanoreceptor for muscle activity during chewing,as well as mediating orthodontic tooth movement.It transforms mechanical stimuli into biological signals,influencing alveolar bone remodeling.Recent research has delved deeper into the biological and mechanical aspects of PDL,emphasizing the importance of understanding its structure and mechanical properties comprehensively.This review focuses on the latest findings concerning both macro-and micro-structural aspects of the PDL,highlighting its mechanical characteristics and factors that influence them.Moreover,it explores the mechanotransduction mechanisms of PDL cells under mechanical forces.Structure-mechanics-mechanotransduction interplay in PDL has been integrated ultimately.By providing an up-to-date overview of our understanding on PDL at various scales,this study lays the foundation for further exploration into PDL-related biomechanics and mechanobiology.展开更多
The mechanical microenvironment affects the morphology and mechanical properties of cells, and it also plays an important role in cell functions. Pluripotent stem cells (PSCs) grow as multicellular colonies, and the c...The mechanical microenvironment affects the morphology and mechanical properties of cells, and it also plays an important role in cell functions. Pluripotent stem cells (PSCs) grow as multicellular colonies, and the coupling effects of cell–cell and cell-extracellular matrix interactions are complex but necessary for the formations and functions of tissues. This paper uses the finite element method to establish a three-dimensional calculation model of a pair of deformed PSCs in contact with each other and considers the growth and depolymerization of actin filaments. Then the effects of substrate stiffness on the morphology of cells and nuclei and the rearrangement of cytoskeleton are demonstrated. As the substrate becomes softer, the nuclei become loose and round, and the actin filaments will be assembled at a lower level, which could promote the formation of compacted cell colony while having a positive effect on maintaining pluripotency and inducing reprogramming efficiency. In addition, stronger activation of cytoskeleton contractility will compress the cytoplasm and nuclei. The cell mechanics model proposed in this paper provides a strategy for studying the cell morphology and cytoskeleton response of the two-cell system under different biophysical stimuli, and also lays the foundation for the further research on more mechanical factors of cell pluripotency.展开更多
Bone injuries and diseases are associated with profound changes in the biophysical properties of living bone tissues,particularly their electrical and mechanical properties.The biophysical properties of healthy bone a...Bone injuries and diseases are associated with profound changes in the biophysical properties of living bone tissues,particularly their electrical and mechanical properties.The biophysical properties of healthy bone are attributed to the complex network of interactions between its various cell types(i.e.,osteocytes,osteoclast,immune cells and vascular endothelial cells)with the surrounding extracellular matrix(ECM)against the backdrop of a myriad of biomechanical and bioelectrical stimuli arising from daily physical activities.Understanding the pathophysiological changes in bone biophysical properties is critical to developing new therapeutic strategies and novel scaffold biomaterials for orthopedic surgery and tissue engineering,as well as provides a basis for the application of various biophysical stimuli as therapeutic agents to restore the physiological microenvironment of injured/diseased bone tissue,to facilitate its repair and regeneration.These include mechanical,electrical,magnetic,thermal and ultrasound stimuli,whichwill be critically examined in this review.A significant advantage of utilizing such biophysical stimuli to facilitate bone healing is that these may be applied non-invasively with minimal damage to surrounding tissues,unlike conventional orthopedic surgical procedures.Furthermore,the effects of such biophysical stimuli can be localized specifically at the bone defect site,unlike drugs or growth factors that tend to diffuse away after delivery,which may result in detrimental side effects at ectopic sites.展开更多
Mechanical forces control a multitude of biological responses in various cells and tissues.The periodontal ligament,located between the tooth’s root and alveolar bone,is a major tissue compartment that is incessantly...Mechanical forces control a multitude of biological responses in various cells and tissues.The periodontal ligament,located between the tooth’s root and alveolar bone,is a major tissue compartment that is incessantly subjected to such mechanical stimulation through either normal or abnormal oral functionality.It is now known that mechanical stimulation activates periodontal ligament stem cells(PDLSCs)to modulate periodontal immunity and regulate inflammation–a basic feature of periodontal disease that affects virtually every human during their lifetime.For instance,shear stress induces the expression of immunomodulatoryrelated gene,indoleamine 2,3-dioxygenase(IDO).IDO cleaves l-tryptophan,resulting in increased l-kynurenine levels that,in turn,further promote regulatory T-cell differentiation and inhibit T cell proliferation.These and other related data reinforce the notion that mechanical stimulation plays a crucial role in controlling inflammation and immunomodulation of periodontal tissues.Further investigations,however,are warranted to evaluate the immunomodulatory features of PDLSCs so as to understand the pathological basis of periodontal disease and translate these into clinical interventions.展开更多
Peripheral nerve injury(PNl)usually causes severe motor,sensory and autonomic dysfunction.In addition to direct surgical repair,rehabilitation exercises,and traditional physical stimuli,for example,electrical stimulat...Peripheral nerve injury(PNl)usually causes severe motor,sensory and autonomic dysfunction.In addition to direct surgical repair,rehabilitation exercises,and traditional physical stimuli,for example,electrical stimulation,have been applied in promoting the clinical recovery of PNI for a long time but showed low efficiency.Recently,significant progress has been made in new physical modulation to promote peripheral nerve regeneration.We hereby review current progress on the mechanism of peripheral nerve regeneration after injury and summarize the new findings and evidence for the application of physical modulation,including electrical stimulation,light,ultrasound,magnetic stimulation,and mechanical stretching in experimental studies and the clinical treatment of patients with PNl.展开更多
Human skin sensory system,featuring a sophisticated threedimensional(3D)distribution of mechanoreceptors within the skin,possesses an exceptional ability to perceive a diverse range of external mechanical stimuli and ...Human skin sensory system,featuring a sophisticated threedimensional(3D)distribution of mechanoreceptors within the skin,possesses an exceptional ability to perceive a diverse range of external mechanical stimuli and accurately recognize object attributes[1].展开更多
Early diagnosis of diabetes is crucial,as diabetes,particularly type 2,can eventually lead to irreversible changes and complications.Conventional techniques,such as the Fasting Plasma Glucose(FPG)Test and Hemoglobin A...Early diagnosis of diabetes is crucial,as diabetes,particularly type 2,can eventually lead to irreversible changes and complications.Conventional techniques,such as the Fasting Plasma Glucose(FPG)Test and Hemoglobin A1c(HbA1c)Test,measure blood glucose levels,which fluctuate over time and are insensitive to early stages.In this study,we focus on measuring the mechanical properties of red blood cells,as their irreversible changes can indicate early pathological impacts of diabetes.We developed a microfluidic chip with a symmetrical hyperbolic structure.By periodically altering the state of the valve membrane,we generate a reciprocating shear flow field that repeatedly acts on groups of RBCs.We then quantify the morphological parameters of the RBCs,establishing a correlation between the reciprocating shear flow field and the morphological changes of the cells.Using the developed microfluidic chip,we investigated the resistance of blood cells from 20 healthy volunteers to mechanical stimuli.The results indicated a significant correlation between the deformability of red blood cells and age,while no such correlation was found among individuals of the same gender.This study highlights the potential of utilizing the mechanical properties of red blood cells as an early diagnostic tool for diabetes.Furthermore,given the ease of integration of microfluidic chips,they present a promising high-throughput diagnostic solution for large-scale clinical screening.展开更多
Peripheral nerve injury(PNI)usually causes severe motor,sensory and autonomic dysfunction.In addition to direct surgical repair,rehabilitation exercises,and traditional physical stimuli,for example,electrical stimulat...Peripheral nerve injury(PNI)usually causes severe motor,sensory and autonomic dysfunction.In addition to direct surgical repair,rehabilitation exercises,and traditional physical stimuli,for example,electrical stimulation,have been applied in promoting the clinical recovery of PNI for a long time but showed low efficiency.Recently,significant progress has been made in new physical modulation to promote peripheral nerve regeneration.We hereby review current progress on the mechanism of peripheral nerve regeneration after injury and summarize the new findings and evidence for the application of physical modulation,including electrical stimulation,light,ultrasound,magnetic stimulation,and mechanical stretching in experimental studies and the clinical treatment of patients with PNI.展开更多
基金part supported by JSPS KAKENHI Grant Number JP23K28396.
文摘This paper presents a fully integrated platform that leverages hardware,software,and specially formulated O/W emulsions to provide localized mechanical stimuli for manipulating cellular behaviors.The system comprises a hexapole magnetic tweezer device,position-based current calculation software,and biocompatible micro-robots embedded with magnetic microbeads for vibration-driven force generation.High-permeability materials in the tweezer tips,combined with fast-response current regulators,enable rapid and precise force control,ensuring uniform and continuous mechanical stimuli in the pico-newton range.Closed-loop control algorithms automatically adjust coil currents based on the micro-robot’s position,thereby compensating for potential hysteresis and optimizing system stability.Experimental results demonstrate stable operation at frequencies up to 4 Hz,with a theoretical possibility of extending to 8 Hz under a 2 A current,delivering mean forces around 20 pN at 1 Hz with a 57μm emulsion.Additionally,the platform allows fine-tuning of forces by altering emulsion size or bead concentrations,thereby providing researchers with a versatile approach to study apoptosis,proliferation,and the other mechanotransduction pathways.The biodegradable and cell-friendly emulsion serves as a protective membrane for the magnetic microbeads while effectively mimicking the mechanical properties of living cells.By bridging the gap between precise motion control and continuous vibrational force application,this novel platform offers a promising tool for advancing targeted cellular studies,fostering insights into tissue engineering,and improving cancer therapies.
基金supported by the National Natural Science Foundation of China(32271416)Sichuan Provincial Science and Technology program(2022YFQ0002).
文摘The periodontal ligament(PDL)plays a crucial role in transmitting and dispersing occlusal force,acting as mechanoreceptor for muscle activity during chewing,as well as mediating orthodontic tooth movement.It transforms mechanical stimuli into biological signals,influencing alveolar bone remodeling.Recent research has delved deeper into the biological and mechanical aspects of PDL,emphasizing the importance of understanding its structure and mechanical properties comprehensively.This review focuses on the latest findings concerning both macro-and micro-structural aspects of the PDL,highlighting its mechanical characteristics and factors that influence them.Moreover,it explores the mechanotransduction mechanisms of PDL cells under mechanical forces.Structure-mechanics-mechanotransduction interplay in PDL has been integrated ultimately.By providing an up-to-date overview of our understanding on PDL at various scales,this study lays the foundation for further exploration into PDL-related biomechanics and mechanobiology.
基金This work was supported by the National Key R&D Program of China(2017YFA0506500,2016YFC1102203,and 2016YFC1101100)the National Natural Science Foundation of China(31370018,11972206,11902114,11421202,11827803,and 11902020)+1 种基金Fundamental Research Funds for the Central Universities(ZG140S1971)Young Elite Scientist Sponsorship Program by CAST(YESS 2015QNRC001).
文摘The mechanical microenvironment affects the morphology and mechanical properties of cells, and it also plays an important role in cell functions. Pluripotent stem cells (PSCs) grow as multicellular colonies, and the coupling effects of cell–cell and cell-extracellular matrix interactions are complex but necessary for the formations and functions of tissues. This paper uses the finite element method to establish a three-dimensional calculation model of a pair of deformed PSCs in contact with each other and considers the growth and depolymerization of actin filaments. Then the effects of substrate stiffness on the morphology of cells and nuclei and the rearrangement of cytoskeleton are demonstrated. As the substrate becomes softer, the nuclei become loose and round, and the actin filaments will be assembled at a lower level, which could promote the formation of compacted cell colony while having a positive effect on maintaining pluripotency and inducing reprogramming efficiency. In addition, stronger activation of cytoskeleton contractility will compress the cytoplasm and nuclei. The cell mechanics model proposed in this paper provides a strategy for studying the cell morphology and cytoskeleton response of the two-cell system under different biophysical stimuli, and also lays the foundation for the further research on more mechanical factors of cell pluripotency.
基金supported by the National Key Research and Development Program of China(2021YFB3800800,2021YFC2400400)National Natural Science Foundation of China(Nos.82022016,51973004,81991505,U22A20160 and 52103312)+3 种基金the Beijing Municipal Natural Science Foundation(7222226)Peking University School of Stomatology National Clinical Key Discipline Construction Project(No.PKUSSNKP-T202101)Beijing Physician Scientist Training Project(BJPSTP-2024-05)Clinical Medicine Plus X-Young Scholars Project(PKU2024LCXQ040).
文摘Bone injuries and diseases are associated with profound changes in the biophysical properties of living bone tissues,particularly their electrical and mechanical properties.The biophysical properties of healthy bone are attributed to the complex network of interactions between its various cell types(i.e.,osteocytes,osteoclast,immune cells and vascular endothelial cells)with the surrounding extracellular matrix(ECM)against the backdrop of a myriad of biomechanical and bioelectrical stimuli arising from daily physical activities.Understanding the pathophysiological changes in bone biophysical properties is critical to developing new therapeutic strategies and novel scaffold biomaterials for orthopedic surgery and tissue engineering,as well as provides a basis for the application of various biophysical stimuli as therapeutic agents to restore the physiological microenvironment of injured/diseased bone tissue,to facilitate its repair and regeneration.These include mechanical,electrical,magnetic,thermal and ultrasound stimuli,whichwill be critically examined in this review.A significant advantage of utilizing such biophysical stimuli to facilitate bone healing is that these may be applied non-invasively with minimal damage to surrounding tissues,unlike conventional orthopedic surgical procedures.Furthermore,the effects of such biophysical stimuli can be localized specifically at the bone defect site,unlike drugs or growth factors that tend to diffuse away after delivery,which may result in detrimental side effects at ectopic sites.
基金supported by the NSRF via the Program Management Unit for Human Resources&Institutional Development,Research and Innovation(B16F640118 to T.O.and H.E.)R.S.is supported by the C2F Scholarship at Chulalongkorn UniversityJ.C.is supported by the Ratchadapiset Somphot Fund for Postdoctoral Fellowship,Chulalongkorn University.
文摘Mechanical forces control a multitude of biological responses in various cells and tissues.The periodontal ligament,located between the tooth’s root and alveolar bone,is a major tissue compartment that is incessantly subjected to such mechanical stimulation through either normal or abnormal oral functionality.It is now known that mechanical stimulation activates periodontal ligament stem cells(PDLSCs)to modulate periodontal immunity and regulate inflammation–a basic feature of periodontal disease that affects virtually every human during their lifetime.For instance,shear stress induces the expression of immunomodulatoryrelated gene,indoleamine 2,3-dioxygenase(IDO).IDO cleaves l-tryptophan,resulting in increased l-kynurenine levels that,in turn,further promote regulatory T-cell differentiation and inhibit T cell proliferation.These and other related data reinforce the notion that mechanical stimulation plays a crucial role in controlling inflammation and immunomodulation of periodontal tissues.Further investigations,however,are warranted to evaluate the immunomodulatory features of PDLSCs so as to understand the pathological basis of periodontal disease and translate these into clinical interventions.
基金supported by Taishan Scholars Program of Shandong Province(tsqn202103189)the National Natural Science Foundation of China(81771298).
文摘Peripheral nerve injury(PNl)usually causes severe motor,sensory and autonomic dysfunction.In addition to direct surgical repair,rehabilitation exercises,and traditional physical stimuli,for example,electrical stimulation,have been applied in promoting the clinical recovery of PNI for a long time but showed low efficiency.Recently,significant progress has been made in new physical modulation to promote peripheral nerve regeneration.We hereby review current progress on the mechanism of peripheral nerve regeneration after injury and summarize the new findings and evidence for the application of physical modulation,including electrical stimulation,light,ultrasound,magnetic stimulation,and mechanical stretching in experimental studies and the clinical treatment of patients with PNl.
文摘Human skin sensory system,featuring a sophisticated threedimensional(3D)distribution of mechanoreceptors within the skin,possesses an exceptional ability to perceive a diverse range of external mechanical stimuli and accurately recognize object attributes[1].
基金the Key Project of the National Natural Science Foundation of China(NSFC)(12432014)the National Key Research and Development Program of China(2025YFE0107500)+2 种基金National Natural Science Foundation of China(51927804)Shaanxi Province Natural Science Basic Research Program Projects(2025JC-YBMS-028)Technology Innovation Guidance Program Fund of Shaanxi Province(2019CGHJ-09).
文摘Early diagnosis of diabetes is crucial,as diabetes,particularly type 2,can eventually lead to irreversible changes and complications.Conventional techniques,such as the Fasting Plasma Glucose(FPG)Test and Hemoglobin A1c(HbA1c)Test,measure blood glucose levels,which fluctuate over time and are insensitive to early stages.In this study,we focus on measuring the mechanical properties of red blood cells,as their irreversible changes can indicate early pathological impacts of diabetes.We developed a microfluidic chip with a symmetrical hyperbolic structure.By periodically altering the state of the valve membrane,we generate a reciprocating shear flow field that repeatedly acts on groups of RBCs.We then quantify the morphological parameters of the RBCs,establishing a correlation between the reciprocating shear flow field and the morphological changes of the cells.Using the developed microfluidic chip,we investigated the resistance of blood cells from 20 healthy volunteers to mechanical stimuli.The results indicated a significant correlation between the deformability of red blood cells and age,while no such correlation was found among individuals of the same gender.This study highlights the potential of utilizing the mechanical properties of red blood cells as an early diagnostic tool for diabetes.Furthermore,given the ease of integration of microfluidic chips,they present a promising high-throughput diagnostic solution for large-scale clinical screening.
基金Taishan Scholars Program of Shandong Province(tsqn202103189)National Natural Science Foundation of China(81771298).
文摘Peripheral nerve injury(PNI)usually causes severe motor,sensory and autonomic dysfunction.In addition to direct surgical repair,rehabilitation exercises,and traditional physical stimuli,for example,electrical stimulation,have been applied in promoting the clinical recovery of PNI for a long time but showed low efficiency.Recently,significant progress has been made in new physical modulation to promote peripheral nerve regeneration.We hereby review current progress on the mechanism of peripheral nerve regeneration after injury and summarize the new findings and evidence for the application of physical modulation,including electrical stimulation,light,ultrasound,magnetic stimulation,and mechanical stretching in experimental studies and the clinical treatment of patients with PNI.
