BACKGROUND： Notch signaling regulates bone marrow mesenchymal stem cell （MSC） proliferation, differentiation, and apoptosis, Notch signaling and Rho kinase signaling exhibit a crosstalk phenomenon with JAK/STAT, an...BACKGROUND： Notch signaling regulates bone marrow mesenchymal stem cell （MSC） proliferation, differentiation, and apoptosis, Notch signaling and Rho kinase signaling exhibit a crosstalk phenomenon with JAK/STAT, and both participate in the neuronal dendritic spine development. Inhibition of RhoA/Rho kinase signaling may regulate MSC differentiation into neuronal-like cells. OBJECTIVE： To investigate the effect of Notch1 signaling on the differentiation of rat MSCs into neurons induced by fasudil hydrochloride （C14H17N3O2S-HCI）, a Rho kinase inhibitor, through a siRNA approach. DESIGN, TIME AND SETTING： An in vitro cytological experiment was performed in the Cell Laboratory of Henan Academy of Medical and Pharmaceutical Sciences between December 2007 and May 2009. MATERIALS： MSCs were obtained from Wistar rat femoral bone, fasudil hydrochloride was provided by -Tianjin Chase Sun Pharmaceutical Co., Ltd. Rn-notchl-siRNa, negative control siRNA （Cy3 label） and Rn-MAPK1 control siRNA were provided by QIAGEN, Coloqne, German. METHODS： The cultured MSCs were divided into non-transfected, transfected group （transfected with Rn-Notchl-siRNA）, positive control （transfected with Rn-MAPK-1 control siRNA）, and negative control （transfected with negative control siRNA） groups. Fasudil hydrochloride was applied to induce MSCs to differentiate into neurons. MAIN OUTCOME MEASURES： The fluorescence expression by the transfected MSCs was observed under an inverted fluorescence microscope; the expression of Notch1 mRNA, Hesl mRNA, and MAPK1 mRNA in MSCs was detected by reverse transcription polymerase chain reaction; the expression of Notch1 protein, nestin, neurofilament M, and glial fibrillary acidic protein was detected by immunocytochemistry. The viability of MSCs was detected by tetrazolium bromide assay. RESULTS： MSC fluorescence increased following a 72-hour siRNA transfection, with transfection efficiencies of up to （0.91 ± 0.04）; the Notch1 mRNA and Hesl mRNA expressed by transfec展开更多
The tilted implant with immediate function is increasingly used in clinical dental therapy for edentulous and partially edentulous patients with excessive bone resorption and the anatomic limitations in the alveolar r...The tilted implant with immediate function is increasingly used in clinical dental therapy for edentulous and partially edentulous patients with excessive bone resorption and the anatomic limitations in the alveolar ridge.However,peri-implant cervical bone loss can be caused by the stress shielding effect.Herein,inspired by the concept of“materiobiology”,the mechanical characteristics of materials were considered along with bone biology for tilted implant design.In this study,a novel Ti-35Nb-2Ta-3Zr alloy(TNTZ)implant with low elastic modulus,high strength and favorable biocompatibility was developed.Then the human alveolar bone environment was mimicked in goat and finite element(FE)models to investigate the mechanical property and the related peri-implant bone remodeling of TNTZ compared to commonly used Ti-6Al-4V(TC4)in tilted implantation under loading condition.Next,a layer-by-layer quantitative correlation of the FE and X-ray Microscopy(XRM)analysis suggested that the TNTZ implant present better mechanobiological characteristics including improved load transduction and increased bone area in the tilted implantation model compared to TC4 implant,especially in the upper 1/3 region of peri-implant bone that is“lower stress”.Finally,combining the static and dynamic parameters of bone,it was further verified that TNTZ enhanced bone remodeling in“lower stress”upper 1/3 region.This study demonstrates that TNTZ is a mechanobiological optimized tilted implant material that enhances load transduction and bone remodeling.展开更多
Biomedicalβ-phase Ti-Nb-Ta-Zr alloys usually exhibit low elastic modulus with inadequate strength.In the present work,a series of newly developed dual-phase Ti-xNb-yTa-2Zr(wt.%)alloys with high performance were inves...Biomedicalβ-phase Ti-Nb-Ta-Zr alloys usually exhibit low elastic modulus with inadequate strength.In the present work,a series of newly developed dual-phase Ti-xNb-yTa-2Zr(wt.%)alloys with high performance were investigated in which the stability ofβ-phase was reduced under the guidelines of ab initio calculations and d-electronic theory.The effects of Nb and Ta contents on the microstructure,compressive and tensile properties were investigated.Results demonstrate that the designed Ti-xNb-yTa-2Zr alloys exhibit typical characteristics ofα+βdual-phase microstructure.The microstructure of the alloys is more sensitive to Nb rather than Ta.The as-cast alloys exhibit needle-likeα′martensite at a lower Nb content of 3 wt.%and lamellarα′martensite at an Nb content of 5 wt.%.Among the alloys,the Ti-3Nb-13Ta-2Zr alloy shows the highest compressive strength(2270±10 MPa)and compressive strain(74.3%±0.4%).This superior performance is due to the combination ofα+βdual-phase microstructure and stressinducedα"martensite.Besides,lattice distortion caused by Ta element also contributes to the compressive properties.Nb and Ta contents of the alloys strongly affect Young's modulus and tensile properties after rolling.The as-rolled Ti-3Nb-13Ta-2Zr alloy exhibits much lower modulus due to lower Nb content as well as moreα"martensite andβphase with a good combination of low modulus and high strength among all the designed alloys.Atom probe tomography analysis reveals the element partitioning between theαandβphases in which Ta concentration is higher than Nb in theαphase.Also,the concentration of Ta is lower than that of Nb in theβphase,indicating that theβ-stability of Nb is higher than that of Ta.This work proposes modernα+βdual-phase Ti-xNb-yTa-2Zr alloys as a new concept to design novel biomedical Ti alloys with high performance.展开更多
The aim of this study was to compare the bone resorption differences between implant placement sites (IPS) and non-implant placement sites (NIPS) after autogenous block bone grafts in the anterior maxilla. Fourteen pa...The aim of this study was to compare the bone resorption differences between implant placement sites (IPS) and non-implant placement sites (NIPS) after autogenous block bone grafts in the anterior maxilla. Fourteen patients (58 edentulous sites) with alveolar atrophy in the anterior maxilla were treated with autogenous block bone grafts. CBCT examinations were performed at 1 month before surgery (T0), immediately after surgery (T1), 3 to 4 months after surgery (T2), 6 to 7 months after surgery before implant placement (T3), 12 to 13 months after surgery (T4), and the longest follow-up point (T5). Alveolar crestal and basal bone width (ACBW, ABBW), and alveolar bone height (ABH) were measured and divided into IPS (30 sites) and NIPS (28 sites). All results were compared by the Wilcoxon Signed Rank test. The bone resorption changes for both groups were the same. For these three parameters, ACBW didn’t change significantly from T2 to T3 and T4 to T5, ABBW didn’t change at every period from T2 to T5, and ABH didn’t change from T4 to T5. The bone resorption volume of ACBW and ABH in NIPS were more than in IPS after implant placement surgery, while the volume of ABBW was similar in both groups. At T5, the bone resorption percentages of ACBW, ABBW, and ABH were 25.57%, 16.85% and 43.84% in IPS, and 33.55%, 15.92% and 46.44% in NIPS. A more rapid loss of alveolar crest in NIPS resulted from implant placement surgery, and this reminded us of the importance of immediate implant placement.展开更多
In this study,mesoporous bioactive glass particles(MBGs) are incorporated into poly(lactic-co-glycolic acid)(PLGA) to fabricate highly interconnected macroporous composite scaffolds with enhanced mechanical and biolog...In this study,mesoporous bioactive glass particles(MBGs) are incorporated into poly(lactic-co-glycolic acid)(PLGA) to fabricate highly interconnected macroporous composite scaffolds with enhanced mechanical and biological properties via a developed supercritical carbon dioxide(scCO_(2)) foaming method Scaffolds show favorable highly interconnected and macroporous structure through a high foaming pressure and long venting time foaming strategy.Specifically,scaffolds with porosity from 73% to 85%,pore size from 120 μm to 320 μm and interconnectivity of over 95% are controllably fabricated at MBG content from 0 wt% to 20 wt%.In comparison with neat PLGA scaffolds,composite scaffolds perform improved strength(up to 1.5 folds) and Young's modulus(up to 3 folds).The interconnected macroporous structure is beneficial to the ingrowth of cells.More importantly,composite scaffolds also provide a more promising microenvironment for cellular proliferation and adhesion with the release of bioactive ions.Hopefully,MBG/PLGA scaffolds developed by the green foaming strategy in this work show promising morphological,mechanical and biological features for tissue regeneration.展开更多
基金the National Natural Science Foundation of China, No. 30770758Natural Science Research Plan of Henan Provincial Education Ministry, No. 2008A320032
文摘BACKGROUND： Notch signaling regulates bone marrow mesenchymal stem cell （MSC） proliferation, differentiation, and apoptosis, Notch signaling and Rho kinase signaling exhibit a crosstalk phenomenon with JAK/STAT, and both participate in the neuronal dendritic spine development. Inhibition of RhoA/Rho kinase signaling may regulate MSC differentiation into neuronal-like cells. OBJECTIVE： To investigate the effect of Notch1 signaling on the differentiation of rat MSCs into neurons induced by fasudil hydrochloride （C14H17N3O2S-HCI）, a Rho kinase inhibitor, through a siRNA approach. DESIGN, TIME AND SETTING： An in vitro cytological experiment was performed in the Cell Laboratory of Henan Academy of Medical and Pharmaceutical Sciences between December 2007 and May 2009. MATERIALS： MSCs were obtained from Wistar rat femoral bone, fasudil hydrochloride was provided by -Tianjin Chase Sun Pharmaceutical Co., Ltd. Rn-notchl-siRNa, negative control siRNA （Cy3 label） and Rn-MAPK1 control siRNA were provided by QIAGEN, Coloqne, German. METHODS： The cultured MSCs were divided into non-transfected, transfected group （transfected with Rn-Notchl-siRNA）, positive control （transfected with Rn-MAPK-1 control siRNA）, and negative control （transfected with negative control siRNA） groups. Fasudil hydrochloride was applied to induce MSCs to differentiate into neurons. MAIN OUTCOME MEASURES： The fluorescence expression by the transfected MSCs was observed under an inverted fluorescence microscope; the expression of Notch1 mRNA, Hesl mRNA, and MAPK1 mRNA in MSCs was detected by reverse transcription polymerase chain reaction; the expression of Notch1 protein, nestin, neurofilament M, and glial fibrillary acidic protein was detected by immunocytochemistry. The viability of MSCs was detected by tetrazolium bromide assay. RESULTS： MSC fluorescence increased following a 72-hour siRNA transfection, with transfection efficiencies of up to （0.91 ± 0.04）; the Notch1 mRNA and Hesl mRNA expressed by transfec
基金supported by the National Natural Science Foundation of China[grant number 52171075,51831011,U2032124]the Medical Engineering Cross Key Research Foundation of the Shanghai Jiao Tong University[grant number YG2017ZD06]+1 种基金the Science and Technology Commission of Shanghai Municipality[grant number 201409006300]the Opening Project of Shanghai Key Laboratory of Orthopaedic Implant[grant number KFKT2021001].
文摘The tilted implant with immediate function is increasingly used in clinical dental therapy for edentulous and partially edentulous patients with excessive bone resorption and the anatomic limitations in the alveolar ridge.However,peri-implant cervical bone loss can be caused by the stress shielding effect.Herein,inspired by the concept of“materiobiology”,the mechanical characteristics of materials were considered along with bone biology for tilted implant design.In this study,a novel Ti-35Nb-2Ta-3Zr alloy(TNTZ)implant with low elastic modulus,high strength and favorable biocompatibility was developed.Then the human alveolar bone environment was mimicked in goat and finite element(FE)models to investigate the mechanical property and the related peri-implant bone remodeling of TNTZ compared to commonly used Ti-6Al-4V(TC4)in tilted implantation under loading condition.Next,a layer-by-layer quantitative correlation of the FE and X-ray Microscopy(XRM)analysis suggested that the TNTZ implant present better mechanobiological characteristics including improved load transduction and increased bone area in the tilted implantation model compared to TC4 implant,especially in the upper 1/3 region of peri-implant bone that is“lower stress”.Finally,combining the static and dynamic parameters of bone,it was further verified that TNTZ enhanced bone remodeling in“lower stress”upper 1/3 region.This study demonstrates that TNTZ is a mechanobiological optimized tilted implant material that enhances load transduction and bone remodeling.
基金financially supported by the National Natural Science Foundation of China(Nos.52011530181 and 51831011)the Shanghai Science and Technology Commission(No.20S31900100)。
文摘Biomedicalβ-phase Ti-Nb-Ta-Zr alloys usually exhibit low elastic modulus with inadequate strength.In the present work,a series of newly developed dual-phase Ti-xNb-yTa-2Zr(wt.%)alloys with high performance were investigated in which the stability ofβ-phase was reduced under the guidelines of ab initio calculations and d-electronic theory.The effects of Nb and Ta contents on the microstructure,compressive and tensile properties were investigated.Results demonstrate that the designed Ti-xNb-yTa-2Zr alloys exhibit typical characteristics ofα+βdual-phase microstructure.The microstructure of the alloys is more sensitive to Nb rather than Ta.The as-cast alloys exhibit needle-likeα′martensite at a lower Nb content of 3 wt.%and lamellarα′martensite at an Nb content of 5 wt.%.Among the alloys,the Ti-3Nb-13Ta-2Zr alloy shows the highest compressive strength(2270±10 MPa)and compressive strain(74.3%±0.4%).This superior performance is due to the combination ofα+βdual-phase microstructure and stressinducedα"martensite.Besides,lattice distortion caused by Ta element also contributes to the compressive properties.Nb and Ta contents of the alloys strongly affect Young's modulus and tensile properties after rolling.The as-rolled Ti-3Nb-13Ta-2Zr alloy exhibits much lower modulus due to lower Nb content as well as moreα"martensite andβphase with a good combination of low modulus and high strength among all the designed alloys.Atom probe tomography analysis reveals the element partitioning between theαandβphases in which Ta concentration is higher than Nb in theαphase.Also,the concentration of Ta is lower than that of Nb in theβphase,indicating that theβ-stability of Nb is higher than that of Ta.This work proposes modernα+βdual-phase Ti-xNb-yTa-2Zr alloys as a new concept to design novel biomedical Ti alloys with high performance.
文摘The aim of this study was to compare the bone resorption differences between implant placement sites (IPS) and non-implant placement sites (NIPS) after autogenous block bone grafts in the anterior maxilla. Fourteen patients (58 edentulous sites) with alveolar atrophy in the anterior maxilla were treated with autogenous block bone grafts. CBCT examinations were performed at 1 month before surgery (T0), immediately after surgery (T1), 3 to 4 months after surgery (T2), 6 to 7 months after surgery before implant placement (T3), 12 to 13 months after surgery (T4), and the longest follow-up point (T5). Alveolar crestal and basal bone width (ACBW, ABBW), and alveolar bone height (ABH) were measured and divided into IPS (30 sites) and NIPS (28 sites). All results were compared by the Wilcoxon Signed Rank test. The bone resorption changes for both groups were the same. For these three parameters, ACBW didn’t change significantly from T2 to T3 and T4 to T5, ABBW didn’t change at every period from T2 to T5, and ABH didn’t change from T4 to T5. The bone resorption volume of ACBW and ABH in NIPS were more than in IPS after implant placement surgery, while the volume of ABBW was similar in both groups. At T5, the bone resorption percentages of ACBW, ABBW, and ABH were 25.57%, 16.85% and 43.84% in IPS, and 33.55%, 15.92% and 46.44% in NIPS. A more rapid loss of alveolar crest in NIPS resulted from implant placement surgery, and this reminded us of the importance of immediate implant placement.
基金the National Natural Science Foundation of China (Grant No. 21676083)the Fundamental Research Funds for the Central Universities111 Project (Grant No. B20031)。
文摘In this study,mesoporous bioactive glass particles(MBGs) are incorporated into poly(lactic-co-glycolic acid)(PLGA) to fabricate highly interconnected macroporous composite scaffolds with enhanced mechanical and biological properties via a developed supercritical carbon dioxide(scCO_(2)) foaming method Scaffolds show favorable highly interconnected and macroporous structure through a high foaming pressure and long venting time foaming strategy.Specifically,scaffolds with porosity from 73% to 85%,pore size from 120 μm to 320 μm and interconnectivity of over 95% are controllably fabricated at MBG content from 0 wt% to 20 wt%.In comparison with neat PLGA scaffolds,composite scaffolds perform improved strength(up to 1.5 folds) and Young's modulus(up to 3 folds).The interconnected macroporous structure is beneficial to the ingrowth of cells.More importantly,composite scaffolds also provide a more promising microenvironment for cellular proliferation and adhesion with the release of bioactive ions.Hopefully,MBG/PLGA scaffolds developed by the green foaming strategy in this work show promising morphological,mechanical and biological features for tissue regeneration.
