Nano-scale phases can enhance or reduce the mechanical properties of materials,so it is very important to control the size of the phases.Copper-rich nanoclusters as matrix defects will significantly reduce the perform...Nano-scale phases can enhance or reduce the mechanical properties of materials,so it is very important to control the size of the phases.Copper-rich nanoclusters as matrix defects will significantly reduce the performance of materials for key nuclear power components,while traditional heat treatment method has a technical bottleneck for the dissolution of nanoclusters.A new method of using the inherent electrical property discrepancies between the matrix material and the nanoclusters to effectively dissolve the nanoclusters through pulsed electric current to realize the recovery of material aging degradation performance is proposed.The performance evolution of simulated steel in the aging-external field repair cycle was studied,and it was found the dislocations as the preferred nucleation sites of nanoclusters were regulated in virtue of the non-thermal effect of current,resulting in a decrease in dislocation density and entanglement release.In the subsequent thermal aging process,the embrittlement rate of the aged and tempered material trained by the electric pulse was slower than that of the untreated sample.When moving dislocations are pinned by nanoclusters under high stress,nano-scale dislocations can be induced into the clusters.The dislocations near the nanoclusters and the newly formed nano-scale dislocations in the nanoclusters act as fast diffusion channels,which can further accelerate the dissolution of the nanoclusters.展开更多
AIM To systematically review the results of studies looking at autologous matrix-induced chondrogenesis(AMIC) in humans. METHODS A literature search was performed, adhering to the PRISMA guidelines, to review any stud...AIM To systematically review the results of studies looking at autologous matrix-induced chondrogenesis(AMIC) in humans. METHODS A literature search was performed, adhering to the PRISMA guidelines, to review any studies using such techniques in humans. Our initial search retrieved 297 articles listed on MEDLINE, Google Scholar, CINHal and EMBASE. From these studies, 15 studies meeting the eligibility criteria were selected and formed the basis of our systematic review.RESULTS The study designs, surgical techniques and outcome measures varied between the studies. Although all studies reported improvements in patient outcome measures, this was not necessarily correlated with magnetic resonance imaging findings. Although there were many additional procedures performed, when AMIC was performed in isolation, the results tended to peak at 24 mo before declining. CONCLUSION Although short-term studies suggest improved patient reported outcomes with a variety of scaffolds, surgical techniques and rehabilitation regimes, the literature remains equivocal on whether the defect size and location, and patient factors affect the outcome. Patientbenefit appears to be maintained in the short-tomedium term but more high level studies with extensive and robust validated outcome measures should be conducted to evaluate the medium-and long-term effect of the AMIC procedure.展开更多
Citation： Utine CA, Engin Durmaz C, Koqak N. Corneal matrix repair therapy with the regenerating agent in neurotrophic persistent epithelial defects, lntJOphthalmo12017;10（12）：1935-1939
Periosteum is a thin membrane that encases the surfaces of most bones.It is composed of an outer fibrous layer contains longitudinally oriented cells and collagen fibers and an inner cambial layer that consists of mul...Periosteum is a thin membrane that encases the surfaces of most bones.It is composed of an outer fibrous layer contains longitudinally oriented cells and collagen fibers and an inner cambial layer that consists of multipotent mesenchymal stem cells（MSCs）and osteogenic progenitor cells.Periosteum has a function of regulating cell and collagen arrangement,which is important to the integrity,modelling and remodelling of bone,particularly during bone defect repair.Apart from autograft and allograft,artificial periosteum,or tissue-engineered periosteum mimicking native periosteum in structure or function,made up of small intestinal submucosa,acellular dermis,induced membrane,cell sheets,and polymeric scaffolds,and so on,has been developed to be used in bone defect repair.In this review,we classify the artificial periosteum into three approaches based on the material source,that is,native tissues,scaffoldfree cell sheets and scaffold-cell composites.Mechanisms,methods and efficacy of each approach are provided.Existing obstacles and enabling technologies for future directions are also discussed.展开更多
This paper reports the results of 24 cases of bone defect resulting from bone tumor or tumor condition excision, and of posterior spinal fusion, treated by human bone matrix gelatin. The success rate of bone defect re...This paper reports the results of 24 cases of bone defect resulting from bone tumor or tumor condition excision, and of posterior spinal fusion, treated by human bone matrix gelatin. The success rate of bone defect repair and spinal fusion is 91. 67 %. The results suggest that human bone matrix gelatin has. excellent osteoinductive effect and is ideal substitute for bone autografts.展开更多
Using a stiffness matrix method, we in- vestigate the propagation behaviors of elastic waves in one-dimensional （1D） piezoelectric/piezomagnetic （PE/PM） phononic crystals （PCs） with line defects by calculating e...Using a stiffness matrix method, we in- vestigate the propagation behaviors of elastic waves in one-dimensional （1D） piezoelectric/piezomagnetic （PE/PM） phononic crystals （PCs） with line defects by calculating energy reflection/transmittion coefficients of quasi-pressure and quasi-shear waves. Line defects are created by the re- placement of PE or PM constituent layer. The defect modes existing in the first gap are considered and the influences on defect modes of the material properties and volume fraction of the defect layers, the type of incident waves, the location of defect layer and the number of structural layers are discussed in detail. Numerical results indicate that defect modes are the most obvious when the defect layers are inserted in the middle of the perfect PCs; the types of incidence wave and material properties of the defect layers have important effects on the numbers, the location of frequencies and the peaks of defect modes, and the defect modes are strongly de- pendent on volume fraction of the defect layers. We hope this paper will be found useful for the design of PE/PM acoustic filters or acoustic transducer with PCs structures.展开更多
The preparation method of urethral extracellular matrix（ECM）was introduced and the biocompatibility of urethral ECM was studied.The urethral segmental defect was created artificially in animal models,which were foll...The preparation method of urethral extracellular matrix（ECM）was introduced and the biocompatibility of urethral ECM was studied.The urethral segmental defect was created artificially in animal models,which were followed by reconstruction with prepared urethral ECM.And postoperative histologic and pathologic exams were employed to evaluate the biocompatibility of urethral ECM.The experimental results show that urethral ECM was biocompatible and can promote cellular interaction as well as tissue development,Urethrography and urodynamic eraluation revealed that there was no difference between the normal and new tissue.The urethral ECM appears to be a useful material for urethral repair in the rabbit.It is biocompatible and for tissue handling.展开更多
The purpose of this study is to explore the feasibility of repairing mandibular defect with osteoconductive porous beta-tricalcium phosphate （ β- TCP ） combined with osteoinductive bone matrix gelatin （ BMG ）, wh...The purpose of this study is to explore the feasibility of repairing mandibular defect with osteoconductive porous beta-tricalcium phosphate （ β- TCP ） combined with osteoinductive bone matrix gelatin （ BMG ）, which has good physical property and biompatibility and maybe a new type of artificial bone substitute. Bilateral mandible defects sized 1.0 cm ×0. 6 cm×0. 3 cm of fifteen rabbits were implanted with β- TCP （ control group ） and β- TCPI BMG（ experimental group ） respectively. The specimens were harvested at 4^th , 8^th and 12^th weeks post-operation and examined by gross, X-ray, histomorphological and the computer analysis. The volume of newly-formed bone of the experimental side was much much than that of the control side at 4^th , 8^th and 12^th weeks. There is significant difference （p 〈 0.05） between experimental group and control group. Computer-aided X- ray analysis showed that the density of newly-formed bone, compared with the control side, were similar to the surrounding natural bone at 12^th week after operntion. Therefore, β- TCP/ BMG is a better bone substitute than TCP and is a degradable and biocompntible artificial bone substitute material and is osteoinductive and osteoconductive .展开更多
The purpose of this study was to assess fetal bovine acellular dermal matrix as a scaffold for supporting the differentiation of bone marrow mesenchymal stem cells into neural cells fol-lowing induction with neural di...The purpose of this study was to assess fetal bovine acellular dermal matrix as a scaffold for supporting the differentiation of bone marrow mesenchymal stem cells into neural cells fol-lowing induction with neural differentiation medium. We performed long-term, continuous observation of cell morphology, growth, differentiation, and neuronal development using several microscopy techniques in conjunction with immunohistochemistry. We examined speciifc neu-ronal proteins and Nissl bodies involved in the differentiation process in order to determine the neuronal differentiation of bone marrow mesenchymal stem cells. The results show that bone marrow mesenchymal stem cells that differentiate on fetal bovine acellular dermal matrix display neuronal morphology with unipolar and bi/multipolar neurite elongations that express neuro-nal-speciifc proteins, includingβIII tubulin. The bone marrow mesenchymal stem cells grown on fetal bovine acellular dermal matrix and induced for long periods of time with neural differen-tiation medium differentiated into a multilayered neural network-like structure with long nerve ifbers that was composed of several parallel microifbers and neuronal cells, forming a complete neural circuit with dendrite-dendrite to axon-dendrite to dendrite-axon synapses. In addition, growth cones with filopodia were observed using scanning electron microscopy. Paraffin sec-tioning showed differentiated bone marrow mesenchymal stem cells with the typical features of neuronal phenotype, such as a large, round nucleus and a cytoplasm full of Nissl bodies. The data suggest that the biological scaffold fetal bovine acellular dermal matrix is capable of supporting human bone marrow mesenchymal stem cell differentiation into functional neurons and the subsequent formation of tissue engineered nerve.展开更多
The correct rate of detection for fabric defect is affected by low contrast of images. Aiming at the problem,frequencytuned salient map is used to detect the fabric defect. Firstly,the images of fabric defect are divi...The correct rate of detection for fabric defect is affected by low contrast of images. Aiming at the problem,frequencytuned salient map is used to detect the fabric defect. Firstly,the images of fabric defect are divided into blocks. Then,the blocks are highlighted by frequency-tuned salient algorithm. Simultaneously,gray-level co-occurrence matrix is used to extract the characteristic value of each rectangular patch. Finally,PNN is used to detect the defect on the fabric image. The performance of proposed algorithm is estimated off-line by two sets of fabric defect images. The theoretical argument is supported by experimental results.展开更多
基金financially supported by National Natural Science Foundation of China(Nos.U21B2082,51874023 and U1860206)the National Key Research and Development Program of China(No.2019YFC1908403)+1 种基金the Fundamental Research Funds for the Central Universities(No.FRF-TP-20–04B)the Recruitment Program of Global Experts。
文摘Nano-scale phases can enhance or reduce the mechanical properties of materials,so it is very important to control the size of the phases.Copper-rich nanoclusters as matrix defects will significantly reduce the performance of materials for key nuclear power components,while traditional heat treatment method has a technical bottleneck for the dissolution of nanoclusters.A new method of using the inherent electrical property discrepancies between the matrix material and the nanoclusters to effectively dissolve the nanoclusters through pulsed electric current to realize the recovery of material aging degradation performance is proposed.The performance evolution of simulated steel in the aging-external field repair cycle was studied,and it was found the dislocations as the preferred nucleation sites of nanoclusters were regulated in virtue of the non-thermal effect of current,resulting in a decrease in dislocation density and entanglement release.In the subsequent thermal aging process,the embrittlement rate of the aged and tempered material trained by the electric pulse was slower than that of the untreated sample.When moving dislocations are pinned by nanoclusters under high stress,nano-scale dislocations can be induced into the clusters.The dislocations near the nanoclusters and the newly formed nano-scale dislocations in the nanoclusters act as fast diffusion channels,which can further accelerate the dissolution of the nanoclusters.
文摘AIM To systematically review the results of studies looking at autologous matrix-induced chondrogenesis(AMIC) in humans. METHODS A literature search was performed, adhering to the PRISMA guidelines, to review any studies using such techniques in humans. Our initial search retrieved 297 articles listed on MEDLINE, Google Scholar, CINHal and EMBASE. From these studies, 15 studies meeting the eligibility criteria were selected and formed the basis of our systematic review.RESULTS The study designs, surgical techniques and outcome measures varied between the studies. Although all studies reported improvements in patient outcome measures, this was not necessarily correlated with magnetic resonance imaging findings. Although there were many additional procedures performed, when AMIC was performed in isolation, the results tended to peak at 24 mo before declining. CONCLUSION Although short-term studies suggest improved patient reported outcomes with a variety of scaffolds, surgical techniques and rehabilitation regimes, the literature remains equivocal on whether the defect size and location, and patient factors affect the outcome. Patientbenefit appears to be maintained in the short-tomedium term but more high level studies with extensive and robust validated outcome measures should be conducted to evaluate the medium-and long-term effect of the AMIC procedure.
文摘Citation： Utine CA, Engin Durmaz C, Koqak N. Corneal matrix repair therapy with the regenerating agent in neurotrophic persistent epithelial defects, lntJOphthalmo12017;10（12）：1935-1939
基金financially supported by National Natural Science Foundation of China(Nos.31525009 and 31271021)National 863 Project(No.2015AA020316)+2 种基金Sichuan Innovative Research Team Program for Young Scientists(No.2016TD0004)Zhejiang Provincial Science and Technology Grant(No.2017C33100)Zhejiang Provincial Natural Science Foundation of China(No.LY17H060010)
文摘Periosteum is a thin membrane that encases the surfaces of most bones.It is composed of an outer fibrous layer contains longitudinally oriented cells and collagen fibers and an inner cambial layer that consists of multipotent mesenchymal stem cells（MSCs）and osteogenic progenitor cells.Periosteum has a function of regulating cell and collagen arrangement,which is important to the integrity,modelling and remodelling of bone,particularly during bone defect repair.Apart from autograft and allograft,artificial periosteum,or tissue-engineered periosteum mimicking native periosteum in structure or function,made up of small intestinal submucosa,acellular dermis,induced membrane,cell sheets,and polymeric scaffolds,and so on,has been developed to be used in bone defect repair.In this review,we classify the artificial periosteum into three approaches based on the material source,that is,native tissues,scaffoldfree cell sheets and scaffold-cell composites.Mechanisms,methods and efficacy of each approach are provided.Existing obstacles and enabling technologies for future directions are also discussed.
文摘This paper reports the results of 24 cases of bone defect resulting from bone tumor or tumor condition excision, and of posterior spinal fusion, treated by human bone matrix gelatin. The success rate of bone defect repair and spinal fusion is 91. 67 %. The results suggest that human bone matrix gelatin has. excellent osteoinductive effect and is ideal substitute for bone autografts.
基金supported by the National Natural Science Foundation of China(11102122)
文摘Using a stiffness matrix method, we in- vestigate the propagation behaviors of elastic waves in one-dimensional （1D） piezoelectric/piezomagnetic （PE/PM） phononic crystals （PCs） with line defects by calculating energy reflection/transmittion coefficients of quasi-pressure and quasi-shear waves. Line defects are created by the re- placement of PE or PM constituent layer. The defect modes existing in the first gap are considered and the influences on defect modes of the material properties and volume fraction of the defect layers, the type of incident waves, the location of defect layer and the number of structural layers are discussed in detail. Numerical results indicate that defect modes are the most obvious when the defect layers are inserted in the middle of the perfect PCs; the types of incidence wave and material properties of the defect layers have important effects on the numbers, the location of frequencies and the peaks of defect modes, and the defect modes are strongly de- pendent on volume fraction of the defect layers. We hope this paper will be found useful for the design of PE/PM acoustic filters or acoustic transducer with PCs structures.
文摘The preparation method of urethral extracellular matrix（ECM）was introduced and the biocompatibility of urethral ECM was studied.The urethral segmental defect was created artificially in animal models,which were followed by reconstruction with prepared urethral ECM.And postoperative histologic and pathologic exams were employed to evaluate the biocompatibility of urethral ECM.The experimental results show that urethral ECM was biocompatible and can promote cellular interaction as well as tissue development,Urethrography and urodynamic eraluation revealed that there was no difference between the normal and new tissue.The urethral ECM appears to be a useful material for urethral repair in the rabbit.It is biocompatible and for tissue handling.
文摘The purpose of this study is to explore the feasibility of repairing mandibular defect with osteoconductive porous beta-tricalcium phosphate （ β- TCP ） combined with osteoinductive bone matrix gelatin （ BMG ）, which has good physical property and biompatibility and maybe a new type of artificial bone substitute. Bilateral mandible defects sized 1.0 cm ×0. 6 cm×0. 3 cm of fifteen rabbits were implanted with β- TCP （ control group ） and β- TCPI BMG（ experimental group ） respectively. The specimens were harvested at 4^th , 8^th and 12^th weeks post-operation and examined by gross, X-ray, histomorphological and the computer analysis. The volume of newly-formed bone of the experimental side was much much than that of the control side at 4^th , 8^th and 12^th weeks. There is significant difference （p 〈 0.05） between experimental group and control group. Computer-aided X- ray analysis showed that the density of newly-formed bone, compared with the control side, were similar to the surrounding natural bone at 12^th week after operntion. Therefore, β- TCP/ BMG is a better bone substitute than TCP and is a degradable and biocompntible artificial bone substitute material and is osteoinductive and osteoconductive .
基金supported by a grant from Construction Project of Gansu Provincial Animal Cell Engineering Center,No.0808NTGA013Program for Innovative Research Team in University of Ministry of Education of China,No.IRT13091
文摘The purpose of this study was to assess fetal bovine acellular dermal matrix as a scaffold for supporting the differentiation of bone marrow mesenchymal stem cells into neural cells fol-lowing induction with neural differentiation medium. We performed long-term, continuous observation of cell morphology, growth, differentiation, and neuronal development using several microscopy techniques in conjunction with immunohistochemistry. We examined speciifc neu-ronal proteins and Nissl bodies involved in the differentiation process in order to determine the neuronal differentiation of bone marrow mesenchymal stem cells. The results show that bone marrow mesenchymal stem cells that differentiate on fetal bovine acellular dermal matrix display neuronal morphology with unipolar and bi/multipolar neurite elongations that express neuro-nal-speciifc proteins, includingβIII tubulin. The bone marrow mesenchymal stem cells grown on fetal bovine acellular dermal matrix and induced for long periods of time with neural differen-tiation medium differentiated into a multilayered neural network-like structure with long nerve ifbers that was composed of several parallel microifbers and neuronal cells, forming a complete neural circuit with dendrite-dendrite to axon-dendrite to dendrite-axon synapses. In addition, growth cones with filopodia were observed using scanning electron microscopy. Paraffin sec-tioning showed differentiated bone marrow mesenchymal stem cells with the typical features of neuronal phenotype, such as a large, round nucleus and a cytoplasm full of Nissl bodies. The data suggest that the biological scaffold fetal bovine acellular dermal matrix is capable of supporting human bone marrow mesenchymal stem cell differentiation into functional neurons and the subsequent formation of tissue engineered nerve.
文摘The correct rate of detection for fabric defect is affected by low contrast of images. Aiming at the problem,frequencytuned salient map is used to detect the fabric defect. Firstly,the images of fabric defect are divided into blocks. Then,the blocks are highlighted by frequency-tuned salient algorithm. Simultaneously,gray-level co-occurrence matrix is used to extract the characteristic value of each rectangular patch. Finally,PNN is used to detect the defect on the fabric image. The performance of proposed algorithm is estimated off-line by two sets of fabric defect images. The theoretical argument is supported by experimental results.
