Objective: To explore the possible correlation between bladder compliance(BC) and the changes in detrusor collagen fiber content after bladder outlet obstruction(BOO).Methods: Ninety healthy female Sprague-Dawley(SD) ...Objective: To explore the possible correlation between bladder compliance(BC) and the changes in detrusor collagen fiber content after bladder outlet obstruction(BOO).Methods: Ninety healthy female Sprague-Dawley(SD) rats were enrolled in this experiment and divided into an experimental group and a control group randomly, using the randomizing table method, with 70 rats in the experimental group and 20 rats in the control group. Six weeks after BOO modeling was established, BC was evaluated through bladder testing. Bladder tissues were then fixed and embedded in paraffin. The tissues were cut into thin slices, followed by Masson staining and observation under a microscope.Results: Compared with the control group, the BC of the experimental group rats increased, and the difference had statistical significance(P < 0.05); the content of detrusor collagen fibers of the rats in the experimental group increased significantly compared to the control group.Conclusions: The content of detrusor collagen fibers increased significantly after BOO, and BC was higher.展开更多
Membrane separation strategies offer promising platform for the emulsion separation.However,the low mechanical strength of membrane separation layers and the trade-off between separation flux and efficiency present si...Membrane separation strategies offer promising platform for the emulsion separation.However,the low mechanical strength of membrane separation layers and the trade-off between separation flux and efficiency present significant challenges.In this study,we report a CFM@UiO-66-NH_(2)membrane with high separation flux,efficiency and stability,through utilizing a robust anti-abrasion collagen fiber membrane(CFM)as the multifunctional support and UiO-66-NH_(2)by an in-situ growth as the separation layer.The high mechanical strength of the CFM compensated for the weakness of the separation layer,while the charge-breaking effect of UiO-66-NH_(2),along with the size sieving of its constituent separating layers and the capillary effect of the collagen fibers,contributed to the potential for efficient separation.Additionally,the CFM@UiO-66-NH_(2)membrane exhibited superhydrophilic properties,making it suitable for separating oil-in-water microemulsions and nanoemulsions stabilized by anionic surfactants.The membrane demonstrated remarkable separation efficiencies of up to 99.960%and a separation flux of370.05 L·m^(-2)·h^(-1).Moreover,it exhibits stability,durability,and abrasion resistance,maintaining excellent separation performance even when exposed to strong acids and alkalis without any damage to its structure and performance.After six cycles of reuse,it achieved a separation flux of 417.97 L·m^(-2)·h^(-1)and a separation efficiency of 99.747%.Furthermore,after undergoing 500 cycles of strong abrasion,the separation flux remained at 124.39 L·m^(-2)·h^(-1),with a separation efficiency of 99.992%.These properties make it suitable for the long-term use in harsh operating environments.We attribute these properties to the electrostatic effect resulting from the amino group on UiO-66-NH_(2)and its in-situ growth on the CFM,which forms a size-screening separation layer.Our work highlights the potential of the CFM@UiO-66-NH_(2)membrane as an environmentally friendly size-screening material for the efficient emulsion wastewater separation.展开更多
The effect of hydrophobic modification on the performances of collagen fibers(CFs)was investigated by using silane coupling agents with different alkyl chains as hydrophobic modifiers.It was found silane could be easi...The effect of hydrophobic modification on the performances of collagen fibers(CFs)was investigated by using silane coupling agents with different alkyl chains as hydrophobic modifiers.It was found silane could be easily grafted onto CF surface through covalent bonds under 5%water content.This modification led to the transformation of surface wettability of CF from hydrophilic to hydrophobic.Interestingly,the change of surface wettability resulted in substantial improvement of the modified CF properties,presenting well dispersity of collagen fibers,higher thermal stability and enhanced mechanical properties in comparison with natural CF.The degree of improvement mainly depended on the length of alkyl chain in silane.Longer alkyl chain produced strong hydrophobicity and subsequently more superior performances of the modified CF.When the length of alkyl chain increased to 18 carbon atoms,the modified CF possessed durable superhydrophobicity even exposed to aqueous solutions of different pH,UV,and organic solvents,and had excellent thermal and mechanical properties like leather fibers.In general,this work clearly revealed that the properties of CF are closely and positively related to the hydrophobicity,which is suggestive in developing new leather making technology.展开更多
The process of in situ tumors developing into malignant tumors and exhibiting invasive behavior is extremely complicated.From a biophysical point of view,it is a phase change process affected by many factors,including...The process of in situ tumors developing into malignant tumors and exhibiting invasive behavior is extremely complicated.From a biophysical point of view,it is a phase change process affected by many factors,including cell-to-cell,cell-to-chemical material,cell-to-environment interaction,etc.In this study,we constructed spheroids based on green fluorescence metastatic breast cancer cells MDA-MB-231 to simulate malignant tumors in vitro,while constructed a three-dimensional(3D)biochip to simulate a micro-environment for the growth and invasion of spheroids.In the experiment,the 3D spheroid was implanted into the chip,and the oriented collagen fibers controlled by collagen concentration and injection rate could guide the MDA-MB-231 cells in the spheroid to undergo directional invasion.The experiment showed that the oriented fibers greatly accelerated the invasion speed of MDA-MB-231 cells compared with the traditional uniform tumor micro-environment,namely obvious invasive branches appeared on the spheroids within 24 hours.In order to analyze this interesting phenomenon,we have developed a quantitative analyzing approach to explore strong angle correlation between the orientation of collagen fibers and invasive direction of cancer cell.The results showed that the oriented collagen fibers produced by the chip can greatly stimulate the invasion potential of cancer cells.This biochip is not only conducive to modeling cancer cell metastasis and studying cell invasion mechanisms,but also has the potential to build a quantitative evaluation platform that can be used in future chemical drug treatments.展开更多
The conventional liquid electrolytes(LEs) have a high level of ionic conductivity;however, they often suffer from the poor processability and safety risks of potential leakage. Although solid-state electrolytes(SSEs) ...The conventional liquid electrolytes(LEs) have a high level of ionic conductivity;however, they often suffer from the poor processability and safety risks of potential leakage. Although solid-state electrolytes(SSEs) can solve these inherent problems of LEs, the ionic conductivity of most SSEs is several magnitudes lower than these of LEs. Herein, we report a novel strategy by building liquid ion-transport channels in a solid framework and prepared an electrolyte-locked separator(ELS) using a collagen fiber membrane(CFm). The liquid electrolyte was primarily infiltrated in the smaller voids of CFm, and its ionic conductivity could attain to 9.0×10-3 S cm-1 when the electrolyte absorption(EA) reached up to 112.0%. After centrifuging treatment, the electrolyte retentions(ER) and ionic conductivities of ELS were 108.93% and 8.37×10-3 S cm-1, respectively, which were much higher than those of commercial cellulose separator(CS), exerting excellent liquid-locking performances. In particular, the electrical double-layer capacitors(EDLC) assembled by ELS or CS were characterized and exhibited similar electrochemical performance,demonstrating the satisfactory ability and applicability of ELS for commercial use. In addition, the ELSbased EDLC exhibited favorable flexibility with relative lower loss of capacitance under different angles of bending.展开更多
In this study, a novel adsorption material amino terminated hyperbranched polyamide collagen fiber( CF-HBPN)was prepared by loading amino terminated hyperbranched polyamide( HBPN) which was synthesized by polycondensa...In this study, a novel adsorption material amino terminated hyperbranched polyamide collagen fiber( CF-HBPN)was prepared by loading amino terminated hyperbranched polyamide( HBPN) which was synthesized by polycondensation of methacrylate and diethylenetriamine onto the surface of collagen fiber( CF) with glutaraldehyde as the cross-linking agent. X-ray photoelectron spectroscopy( XPS) and thermogravimetric analysis( TGA) were employed to characterize the structures of CF and CFHBPN. In addition,the adsorption property of CF-HBPN toward Cr( Ⅵ) and adsorption thermodynamic were studied as well. The experimental results indicated that the Cr( Ⅵ) 's removal rate by CF-HBPN was 3. 09 higher than that of CF under the same conditions. Langmuir single layer adsorption model was found more suitable to describe the adsorption process than Freundlich adsorption model. The adsorption process was an endothermic reaction. The adsorption efficiency was enhanced with the increase of temperature. X-ray diffraction( XRD) was employed to elucidate the difference between CF-HBPN and Cr( Ⅵ) loaded CF-HBPN[CF-HBPN-Cr( Ⅵ) ].展开更多
Increasing data indicate that cancer cell migration is regulated by extracellular matrixes and their surrounding biochemical microenvironment,playing a crucial role in pathological processes such as tumor invasion and...Increasing data indicate that cancer cell migration is regulated by extracellular matrixes and their surrounding biochemical microenvironment,playing a crucial role in pathological processes such as tumor invasion and metastasis.However,conventional two-dimensional cell culture and animal models have limitations in studying the influence of tumor microenvironment on cancer cell migration.Fortunately,the further development of microfluidic technology has provided solutions for the study of such questions.We utilize microfluidic chip to build a random collagen fiber microenvironment(RFM)model and an oriented collagen fiber microenvironment(OFM)model that resemble early stage and late stage breast cancer microenvironments,respectively.By combining cell culture,biochemical concentration gradient construction,and microscopic imaging techniques,we investigate the impact of different collagen fiber biochemical microenvironments on the migration of breast cancer MDA-MB-231-RFP cells.The results show that MDA-MB-231-RFP cells migrate further in the OFM model compared to the RFM model,with significant differences observed.Furthermore,we establish concentration gradients of the anticancer drug paclitaxel in both the RFM and OFM models and find that paclitaxel significantly inhibits the migration of MDA-MB-231-RFP cells in the RFM model,with stronger inhibition on the high concentration side compared to the low concentration side.However,the inhibitory effect of paclitaxel on the migration of MDA-MB-231-RFP cells in the OFM model is weak.These findings suggest that the oriented collagen fiber microenvironment resembling the late-stage tumor microenvironment is more favorable for cancer cell migration and that the effectiveness of anticancer drugs is diminished.The RFM and OFM models constructed in this study not only provide a platform for studying the mechanism of cancer development,but also serve as a tool for the initial measurement of drug screening.展开更多
The mechanical response of the human arterial wall under the combined loading of inflation,axial extension,and torsion is examined within the framework of the large deformation hyper-elastic theory.The probability of ...The mechanical response of the human arterial wall under the combined loading of inflation,axial extension,and torsion is examined within the framework of the large deformation hyper-elastic theory.The probability of the aneurysm formation is explained with the instability theory of structure,and the probability of its rupture is explained with the strength theory of material.Taking account of the residual stress and the smooth muscle activities,a two layer thick-walled circular cylindrical tube model with fiber-reinforced composite-based incompressible anisotropic hyper-elastic materials is employed to model the mechanical behavior of the arterial wall.The deformation curves and the stress distributions of the arterial wall are given under normal and abnormal conditions.The results of the deformation and the structure instability analysis show that the model can describe the uniform inflation deformation of the arterial wall under normal conditions,as well as formation and growth of an aneurysm under abnormal conditions such as the decreased stiffness of the elastic and collagen fibers.Prom the analysis of the stresses and the material strength,the rupture of an aneurysm may also be described by this model if the wall stress is larger than its strength.展开更多
AIM: To evaluate the structural organization of the elastic and collagen fibers in the region of the ileocecal transition in 30 young and old male Wistar rats. METHODS: Histology, immunohistochemistry(IHC), transmissi...AIM: To evaluate the structural organization of the elastic and collagen fibers in the region of the ileocecal transition in 30 young and old male Wistar rats. METHODS: Histology, immunohistochemistry(IHC), transmission electron microscopy and scanning electron microscopy were employed in this study. The results demonstrated that there was a demarcation of the ileocecal region between the ileum and the cecum in both groups. RESULTS: The connective tissue fibers had different distribution patterns in the two groups. IHC revealed the presence of nitric oxide synthase, enteric neurons and smooth muscle fibers in the ileocecal junctions(ICJs) of both groups. Compared to the young group, the elderly group exhibited an increase in collagen type Ⅰ?fibers, a decrease in collagen type Ⅲ fibers, a decreased linear density of oxytalan elastic fibers, and a greater linear density of elaunin and mature elastic fibers. CONCLUSION: The results revealed changes in the patterns of distribution of collagen and elastic fibers that may lead to a possible decrease in ICJ functionality.展开更多
In the search for sustainable alternatives to harmful synthetic fibers,an increasing amount of research focuses on biomimicry and natural fibers.Sea silk is an exceptional textile material.It is a kind of natural silk...In the search for sustainable alternatives to harmful synthetic fibers,an increasing amount of research focuses on biomimicry and natural fibers.Sea silk is an exceptional textile material.It is a kind of natural silk produced using the long silky filaments secreted by a specific bivalve mollusk(Pinna nobilis);now at edge of extinction.This paper suggests a simple but effective way to prepare artificial sea silk from Mytilus edulis.A sea silk solution is prepared using a Mytilus edulis protein,and a polyvinyl alcohol(PVA)solution is mixed with the sea silk solution in order to produce artificial sea silk through a bubble electrospinning technique.The effects of the sea silk concentration on the nanofiber’s morphology and mechanical properties are studied experimentally.展开更多
Developing high-performance separation membrane with good durability is a highly desired while challenging issue.Herein,we reported the successful fabrication of chemically and mechanically durable superhydrophobic me...Developing high-performance separation membrane with good durability is a highly desired while challenging issue.Herein,we reported the successful fabrication of chemically and mechanically durable superhydrophobic membrane that was prepared by embedding UiO-66 as size-sieving sites within the supramolecular fiber structure of collagen fiber membrane(CFM),followed by the polydimethylsiloxane(PDMS)coating.The as-prepared CFM/UiO-66(12)/PDMS membrane featured capillary effect-enhanced separation flux and homogeneous porous channels guaranteed high separation efficiency.When utilized as double-layer separation membranes,this new type of composite membranes separated various surfactant stabilized water-in-oil microemulsions and nanoemulsions,with the separation efficiency high up to 99.993%and the flux as high as 973.3 L m−2 h−1.Compared with commercial polytetrafluoro ethylene(PTFE)membrane,the advantage of the double-layer CFM/UiO-66(12)/PDMS membranes in separation flux was evident,which exhibited one order of magnitude higher than that of commercial PTFE membrane.The CFM/UiO-66(12)/PDMS membrane was acid-alkali tolerant,UV-aging resistant and reusable for emulsion separation.Notably,the CFM/UiO-66(12)/PDMS membrane was mechanically durable against strong mechanical abrasion,which was still capable of separating diverse water-in-oil emulsions after the abrasion with sandpaper and assembled as double-layer separation membranes.We anticipate that the combination of CFM and metal organic frameworks(MOFs)is an effective strategy for fabricating high-performance separation membrane with high mechanical and chemical durability.展开更多
Emergencies often result in uncontrollable bleeding, which is thought to be the leading cause of death at the scene of the injured. Among various hemostasis scenarios, collagen fiber (CF) is gradually replacing tradit...Emergencies often result in uncontrollable bleeding, which is thought to be the leading cause of death at the scene of the injured. Among various hemostasis scenarios, collagen fiber (CF) is gradually replacing traditional hemostatic materials due to its superior properties and ease of sourcing from animals. Herein, we use CF and the natural herba-ceous Bletilla striata as raw materials to prepare a collagen fiber-oxidized Bletilla striata composite hemostatic sponge (CFOB). During the cross-linking process, the triple helix structure of collagen stays intact, and its porous three- dimensional network structure brings excellent bulkiness and water absorption properties. Experiments show that the optimal amount of sponge CFOB-10, namely oxidized Bletilla striata polysaccharide 0.5 mg/mL and CF 5 mg/mL, only needed 25 ± 4.06 s for hemostasis time in the rat liver hemorrhage model. In addition, CFOB meets the safety performance requirements of cytotoxicity classification standard 0. Therefore, the optimal amount of CFOB is an excel-lent new hemostatic material with application potential.展开更多
文摘Objective: To explore the possible correlation between bladder compliance(BC) and the changes in detrusor collagen fiber content after bladder outlet obstruction(BOO).Methods: Ninety healthy female Sprague-Dawley(SD) rats were enrolled in this experiment and divided into an experimental group and a control group randomly, using the randomizing table method, with 70 rats in the experimental group and 20 rats in the control group. Six weeks after BOO modeling was established, BC was evaluated through bladder testing. Bladder tissues were then fixed and embedded in paraffin. The tissues were cut into thin slices, followed by Masson staining and observation under a microscope.Results: Compared with the control group, the BC of the experimental group rats increased, and the difference had statistical significance(P < 0.05); the content of detrusor collagen fibers of the rats in the experimental group increased significantly compared to the control group.Conclusions: The content of detrusor collagen fibers increased significantly after BOO, and BC was higher.
基金supported by National Natural Science Foundation of China(22008035,22108040,22378066)Science and Technology Project of Environmental Protection in Fujian(2022R026)Natural Science Foundation of Fujian Province(2020J05131,2020J05130)。
文摘Membrane separation strategies offer promising platform for the emulsion separation.However,the low mechanical strength of membrane separation layers and the trade-off between separation flux and efficiency present significant challenges.In this study,we report a CFM@UiO-66-NH_(2)membrane with high separation flux,efficiency and stability,through utilizing a robust anti-abrasion collagen fiber membrane(CFM)as the multifunctional support and UiO-66-NH_(2)by an in-situ growth as the separation layer.The high mechanical strength of the CFM compensated for the weakness of the separation layer,while the charge-breaking effect of UiO-66-NH_(2),along with the size sieving of its constituent separating layers and the capillary effect of the collagen fibers,contributed to the potential for efficient separation.Additionally,the CFM@UiO-66-NH_(2)membrane exhibited superhydrophilic properties,making it suitable for separating oil-in-water microemulsions and nanoemulsions stabilized by anionic surfactants.The membrane demonstrated remarkable separation efficiencies of up to 99.960%and a separation flux of370.05 L·m^(-2)·h^(-1).Moreover,it exhibits stability,durability,and abrasion resistance,maintaining excellent separation performance even when exposed to strong acids and alkalis without any damage to its structure and performance.After six cycles of reuse,it achieved a separation flux of 417.97 L·m^(-2)·h^(-1)and a separation efficiency of 99.747%.Furthermore,after undergoing 500 cycles of strong abrasion,the separation flux remained at 124.39 L·m^(-2)·h^(-1),with a separation efficiency of 99.992%.These properties make it suitable for the long-term use in harsh operating environments.We attribute these properties to the electrostatic effect resulting from the amino group on UiO-66-NH_(2)and its in-situ growth on the CFM,which forms a size-screening separation layer.Our work highlights the potential of the CFM@UiO-66-NH_(2)membrane as an environmentally friendly size-screening material for the efficient emulsion wastewater separation.
基金The National Natural Science Foundation of China(No.21978176).
文摘The effect of hydrophobic modification on the performances of collagen fibers(CFs)was investigated by using silane coupling agents with different alkyl chains as hydrophobic modifiers.It was found silane could be easily grafted onto CF surface through covalent bonds under 5%water content.This modification led to the transformation of surface wettability of CF from hydrophilic to hydrophobic.Interestingly,the change of surface wettability resulted in substantial improvement of the modified CF properties,presenting well dispersity of collagen fibers,higher thermal stability and enhanced mechanical properties in comparison with natural CF.The degree of improvement mainly depended on the length of alkyl chain in silane.Longer alkyl chain produced strong hydrophobicity and subsequently more superior performances of the modified CF.When the length of alkyl chain increased to 18 carbon atoms,the modified CF possessed durable superhydrophobicity even exposed to aqueous solutions of different pH,UV,and organic solvents,and had excellent thermal and mechanical properties like leather fibers.In general,this work clearly revealed that the properties of CF are closely and positively related to the hydrophobicity,which is suggestive in developing new leather making technology.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11974066 and 11674043)the Fundamental Research Funds for the Central Universities,China(Grant No.2019CDYGYB007)the Natural Science Foundation of Chongqing,China(Grant No.cstc2019jcyj-msxmX0477).
文摘The process of in situ tumors developing into malignant tumors and exhibiting invasive behavior is extremely complicated.From a biophysical point of view,it is a phase change process affected by many factors,including cell-to-cell,cell-to-chemical material,cell-to-environment interaction,etc.In this study,we constructed spheroids based on green fluorescence metastatic breast cancer cells MDA-MB-231 to simulate malignant tumors in vitro,while constructed a three-dimensional(3D)biochip to simulate a micro-environment for the growth and invasion of spheroids.In the experiment,the 3D spheroid was implanted into the chip,and the oriented collagen fibers controlled by collagen concentration and injection rate could guide the MDA-MB-231 cells in the spheroid to undergo directional invasion.The experiment showed that the oriented fibers greatly accelerated the invasion speed of MDA-MB-231 cells compared with the traditional uniform tumor micro-environment,namely obvious invasive branches appeared on the spheroids within 24 hours.In order to analyze this interesting phenomenon,we have developed a quantitative analyzing approach to explore strong angle correlation between the orientation of collagen fibers and invasive direction of cancer cell.The results showed that the oriented collagen fibers produced by the chip can greatly stimulate the invasion potential of cancer cells.This biochip is not only conducive to modeling cancer cell metastasis and studying cell invasion mechanisms,but also has the potential to build a quantitative evaluation platform that can be used in future chemical drug treatments.
基金supported by the National Natural Science Foundation of China (21878191)。
文摘The conventional liquid electrolytes(LEs) have a high level of ionic conductivity;however, they often suffer from the poor processability and safety risks of potential leakage. Although solid-state electrolytes(SSEs) can solve these inherent problems of LEs, the ionic conductivity of most SSEs is several magnitudes lower than these of LEs. Herein, we report a novel strategy by building liquid ion-transport channels in a solid framework and prepared an electrolyte-locked separator(ELS) using a collagen fiber membrane(CFm). The liquid electrolyte was primarily infiltrated in the smaller voids of CFm, and its ionic conductivity could attain to 9.0×10-3 S cm-1 when the electrolyte absorption(EA) reached up to 112.0%. After centrifuging treatment, the electrolyte retentions(ER) and ionic conductivities of ELS were 108.93% and 8.37×10-3 S cm-1, respectively, which were much higher than those of commercial cellulose separator(CS), exerting excellent liquid-locking performances. In particular, the electrical double-layer capacitors(EDLC) assembled by ELS or CS were characterized and exhibited similar electrochemical performance,demonstrating the satisfactory ability and applicability of ELS for commercial use. In addition, the ELSbased EDLC exhibited favorable flexibility with relative lower loss of capacitance under different angles of bending.
基金National Natural Science Foundation of China(No.21276151)the National High Technology Research and Development Program of China(No.2011AA06A108)+1 种基金Key Scientific Research Group of Shaanxi Province,China(No.2013KCT-08)Postgraduate Innovation Project Funding of Shaanxi University of Science and Technology,China(No.2014019)
文摘In this study, a novel adsorption material amino terminated hyperbranched polyamide collagen fiber( CF-HBPN)was prepared by loading amino terminated hyperbranched polyamide( HBPN) which was synthesized by polycondensation of methacrylate and diethylenetriamine onto the surface of collagen fiber( CF) with glutaraldehyde as the cross-linking agent. X-ray photoelectron spectroscopy( XPS) and thermogravimetric analysis( TGA) were employed to characterize the structures of CF and CFHBPN. In addition,the adsorption property of CF-HBPN toward Cr( Ⅵ) and adsorption thermodynamic were studied as well. The experimental results indicated that the Cr( Ⅵ) 's removal rate by CF-HBPN was 3. 09 higher than that of CF under the same conditions. Langmuir single layer adsorption model was found more suitable to describe the adsorption process than Freundlich adsorption model. The adsorption process was an endothermic reaction. The adsorption efficiency was enhanced with the increase of temperature. X-ray diffraction( XRD) was employed to elucidate the difference between CF-HBPN and Cr( Ⅵ) loaded CF-HBPN[CF-HBPN-Cr( Ⅵ) ].
基金support from the National Natural Science Foundation of China(Grant Nos.11974066,12174041,12104134,T2350007,and 12347178)the Fundamental and Advanced Research Program of Chongqing(Grant No.cstc2019jcyj-msxm X0477)+3 种基金the Natural Science Foundation of Chongqing(Grant No.CSTB2022NSCQMSX1260)the Science and Technology Research Program of Chongqing Municipal Education Commission(Grant No.KJQN202301333)the Scientific Research Fund of Chongqing University of Arts and Sciences(Grant Nos.R2023HH03 and P2022HH05)College Students’Innovation and Entrepreneurship Training Program of Chongqing Municipal(Grant No.S202310642002)。
文摘Increasing data indicate that cancer cell migration is regulated by extracellular matrixes and their surrounding biochemical microenvironment,playing a crucial role in pathological processes such as tumor invasion and metastasis.However,conventional two-dimensional cell culture and animal models have limitations in studying the influence of tumor microenvironment on cancer cell migration.Fortunately,the further development of microfluidic technology has provided solutions for the study of such questions.We utilize microfluidic chip to build a random collagen fiber microenvironment(RFM)model and an oriented collagen fiber microenvironment(OFM)model that resemble early stage and late stage breast cancer microenvironments,respectively.By combining cell culture,biochemical concentration gradient construction,and microscopic imaging techniques,we investigate the impact of different collagen fiber biochemical microenvironments on the migration of breast cancer MDA-MB-231-RFP cells.The results show that MDA-MB-231-RFP cells migrate further in the OFM model compared to the RFM model,with significant differences observed.Furthermore,we establish concentration gradients of the anticancer drug paclitaxel in both the RFM and OFM models and find that paclitaxel significantly inhibits the migration of MDA-MB-231-RFP cells in the RFM model,with stronger inhibition on the high concentration side compared to the low concentration side.However,the inhibitory effect of paclitaxel on the migration of MDA-MB-231-RFP cells in the OFM model is weak.These findings suggest that the oriented collagen fiber microenvironment resembling the late-stage tumor microenvironment is more favorable for cancer cell migration and that the effectiveness of anticancer drugs is diminished.The RFM and OFM models constructed in this study not only provide a platform for studying the mechanism of cancer development,but also serve as a tool for the initial measurement of drug screening.
基金Project supported by the National Natural Science Foundation of China (Nos.10772104 and 10872045)the Innovation Project of the Shanghai Municipal Education Commission (No.09YZ12)the Shanghai Leading Academic Discipline Project (No.S30106)
文摘The mechanical response of the human arterial wall under the combined loading of inflation,axial extension,and torsion is examined within the framework of the large deformation hyper-elastic theory.The probability of the aneurysm formation is explained with the instability theory of structure,and the probability of its rupture is explained with the strength theory of material.Taking account of the residual stress and the smooth muscle activities,a two layer thick-walled circular cylindrical tube model with fiber-reinforced composite-based incompressible anisotropic hyper-elastic materials is employed to model the mechanical behavior of the arterial wall.The deformation curves and the stress distributions of the arterial wall are given under normal and abnormal conditions.The results of the deformation and the structure instability analysis show that the model can describe the uniform inflation deformation of the arterial wall under normal conditions,as well as formation and growth of an aneurysm under abnormal conditions such as the decreased stiffness of the elastic and collagen fibers.Prom the analysis of the stresses and the material strength,the rupture of an aneurysm may also be described by this model if the wall stress is larger than its strength.
文摘AIM: To evaluate the structural organization of the elastic and collagen fibers in the region of the ileocecal transition in 30 young and old male Wistar rats. METHODS: Histology, immunohistochemistry(IHC), transmission electron microscopy and scanning electron microscopy were employed in this study. The results demonstrated that there was a demarcation of the ileocecal region between the ileum and the cecum in both groups. RESULTS: The connective tissue fibers had different distribution patterns in the two groups. IHC revealed the presence of nitric oxide synthase, enteric neurons and smooth muscle fibers in the ileocecal junctions(ICJs) of both groups. Compared to the young group, the elderly group exhibited an increase in collagen type Ⅰ?fibers, a decrease in collagen type Ⅲ fibers, a decreased linear density of oxytalan elastic fibers, and a greater linear density of elaunin and mature elastic fibers. CONCLUSION: The results revealed changes in the patterns of distribution of collagen and elastic fibers that may lead to a possible decrease in ICJ functionality.
基金the Foundation of Xi’an University of Architecture and Technology in 2020[Tian Dan]The Natural Science Foundation of Shaan Xi Province in 2019[2019JQ-755]the Natural Science Foundation of Shaanxi Provincial Department of Education in 2019[19JK0462].
文摘In the search for sustainable alternatives to harmful synthetic fibers,an increasing amount of research focuses on biomimicry and natural fibers.Sea silk is an exceptional textile material.It is a kind of natural silk produced using the long silky filaments secreted by a specific bivalve mollusk(Pinna nobilis);now at edge of extinction.This paper suggests a simple but effective way to prepare artificial sea silk from Mytilus edulis.A sea silk solution is prepared using a Mytilus edulis protein,and a polyvinyl alcohol(PVA)solution is mixed with the sea silk solution in order to produce artificial sea silk through a bubble electrospinning technique.The effects of the sea silk concentration on the nanofiber’s morphology and mechanical properties are studied experimentally.
基金National Natural Science Funds for Excellent Youth Scholars(No.21922808)the National Key Research and Development Program(No.2018YFC1901101)+2 种基金the Fok Ying Tong Education Foundation for Young Teachers in the Higher Education Institutions of China(No.161099)the National Natural Science Foundation of China(No.21978176)the 1000 Talents Program of Sichuan Province.
文摘Developing high-performance separation membrane with good durability is a highly desired while challenging issue.Herein,we reported the successful fabrication of chemically and mechanically durable superhydrophobic membrane that was prepared by embedding UiO-66 as size-sieving sites within the supramolecular fiber structure of collagen fiber membrane(CFM),followed by the polydimethylsiloxane(PDMS)coating.The as-prepared CFM/UiO-66(12)/PDMS membrane featured capillary effect-enhanced separation flux and homogeneous porous channels guaranteed high separation efficiency.When utilized as double-layer separation membranes,this new type of composite membranes separated various surfactant stabilized water-in-oil microemulsions and nanoemulsions,with the separation efficiency high up to 99.993%and the flux as high as 973.3 L m−2 h−1.Compared with commercial polytetrafluoro ethylene(PTFE)membrane,the advantage of the double-layer CFM/UiO-66(12)/PDMS membranes in separation flux was evident,which exhibited one order of magnitude higher than that of commercial PTFE membrane.The CFM/UiO-66(12)/PDMS membrane was acid-alkali tolerant,UV-aging resistant and reusable for emulsion separation.Notably,the CFM/UiO-66(12)/PDMS membrane was mechanically durable against strong mechanical abrasion,which was still capable of separating diverse water-in-oil emulsions after the abrasion with sandpaper and assembled as double-layer separation membranes.We anticipate that the combination of CFM and metal organic frameworks(MOFs)is an effective strategy for fabricating high-performance separation membrane with high mechanical and chemical durability.
基金Opening Project of Key Laboratory of Leather Chemistry and Engineering,(Sichuan University),Ministry of Education,(SCU2021D005)the Fundamental Research Funds for the Central Universities(20826041E4156 and 20826041C4159).
文摘Emergencies often result in uncontrollable bleeding, which is thought to be the leading cause of death at the scene of the injured. Among various hemostasis scenarios, collagen fiber (CF) is gradually replacing traditional hemostatic materials due to its superior properties and ease of sourcing from animals. Herein, we use CF and the natural herba-ceous Bletilla striata as raw materials to prepare a collagen fiber-oxidized Bletilla striata composite hemostatic sponge (CFOB). During the cross-linking process, the triple helix structure of collagen stays intact, and its porous three- dimensional network structure brings excellent bulkiness and water absorption properties. Experiments show that the optimal amount of sponge CFOB-10, namely oxidized Bletilla striata polysaccharide 0.5 mg/mL and CF 5 mg/mL, only needed 25 ± 4.06 s for hemostasis time in the rat liver hemorrhage model. In addition, CFOB meets the safety performance requirements of cytotoxicity classification standard 0. Therefore, the optimal amount of CFOB is an excel-lent new hemostatic material with application potential.
文摘Microscopic imaging based on second-harmonic generation has been proving to be a powerful tool for biomedical studies, especially in that tissues with
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.11972242 and 12272250)China Postdoctoral Science Foundation(Grant No.2020M680913)Shanxi Scholarship Council of China and Shanxi Postgraduate Innovation Project.
