背景间充质干细胞来源的凋亡囊泡具有促进骨组织再生的作用,目前关于人牙髓干细胞凋亡囊泡(apoptotic vesicles derived from human dental pulp stem cells,hDPSC-apovs)用于骨组织再生的研究尚未见报道。目的探讨hDPSC-apovs对小鼠骨...背景间充质干细胞来源的凋亡囊泡具有促进骨组织再生的作用,目前关于人牙髓干细胞凋亡囊泡(apoptotic vesicles derived from human dental pulp stem cells,hDPSC-apovs)用于骨组织再生的研究尚未见报道。目的探讨hDPSC-apovs对小鼠骨髓间充质干细胞(mouse bone marrow mesenchymal stem cells,mBMSC)增殖和成骨分化能力的影响。方法原代培养、分离和鉴定hDPSC,采用星孢素(staurosporine,STS)诱导细胞凋亡,高速离心法分离hDPSC-apovs并鉴定。将mBMSC与不同浓度的hDPSC-apovs(0μg/mL、0.2μg/mL、1μg/mL、5μg/mL、25μg/mL)进行共培养,CCK-8法检测不同浓度hDPSCapovs对mBMSC增殖能力的影响。mBMSC与不同浓度的hDPSC-apovs在成骨诱导培养基中共培养7 d后,茜素红染色分析钙结节形成,qPCR检测各组mBMSC的成骨分化相关基因Alp、Runx2、Spp1、Bglap的表达。结果与不含hDPSCapovs的对照组相比,0.2μg/mL、lμg/mL浓度hDPSC-apovs均能够促进mBMSC的增殖(P<0.05),而5μg/mL、25μg/mL浓度hDPSC-apovs则抑制mBMSC的增殖(P<0.05)。各浓度hDPSC-apovs处理组的钙结节形成量均高于对照组(P<0.05);qPCR结果显示,5μg/mL、25μg/mL组Alp、Runx2、Spp1、Bglap表达均上调(P<0.05),1μg/mL组只有Alp和Runx2表达上调,0.2μg/mL组仅有Alp表达水平上调(P<0.05)。结论在本研究浓度范围内,低浓度的hDPSC-apovs对mBMSC增殖具有促进作用,高浓度则表现为抑制作用;hDPSC-apovs对于mBMSC的成骨分化有一定促进作用,且不同浓度hDPSCapovs对成骨相关基因表达的影响不同。展开更多
This paper presents the design of a novel honeycomb structure with a double curved beam.The purpose of this design is to achieve vibration isolation for the main engine of an offshore platform and reduce impact loads....This paper presents the design of a novel honeycomb structure with a double curved beam.The purpose of this design is to achieve vibration isolation for the main engine of an offshore platform and reduce impact loads.An analytical formula for the force-displacement relationship of the honeycomb single-cell structure is presented based on the modal superposition method.This formula provides a theoretical basis for predicting the compression performance of honeycomb structures.The effects of structural geometric parameters,series and parallel connection methods on the mechanical and energy absorption properties are investigated through mathematical modeling and experimental methods.Furthermore,the study focuses on the vibration isolation and impact resistance performance of honeycomb panels.The results show that the designed honeycomb structure has good mechanical and energy absorption performance,and its energy absorption effect is related to the geometric parameters and series and parallel connection methods of the structure.The isolation efficiency of the honeycomb with 4 rows and 3 columns reaches 38%.The initial isolation frequency of the isolator is 11.7 Hz.展开更多
文摘背景间充质干细胞来源的凋亡囊泡具有促进骨组织再生的作用,目前关于人牙髓干细胞凋亡囊泡(apoptotic vesicles derived from human dental pulp stem cells,hDPSC-apovs)用于骨组织再生的研究尚未见报道。目的探讨hDPSC-apovs对小鼠骨髓间充质干细胞(mouse bone marrow mesenchymal stem cells,mBMSC)增殖和成骨分化能力的影响。方法原代培养、分离和鉴定hDPSC,采用星孢素(staurosporine,STS)诱导细胞凋亡,高速离心法分离hDPSC-apovs并鉴定。将mBMSC与不同浓度的hDPSC-apovs(0μg/mL、0.2μg/mL、1μg/mL、5μg/mL、25μg/mL)进行共培养,CCK-8法检测不同浓度hDPSCapovs对mBMSC增殖能力的影响。mBMSC与不同浓度的hDPSC-apovs在成骨诱导培养基中共培养7 d后,茜素红染色分析钙结节形成,qPCR检测各组mBMSC的成骨分化相关基因Alp、Runx2、Spp1、Bglap的表达。结果与不含hDPSCapovs的对照组相比,0.2μg/mL、lμg/mL浓度hDPSC-apovs均能够促进mBMSC的增殖(P<0.05),而5μg/mL、25μg/mL浓度hDPSC-apovs则抑制mBMSC的增殖(P<0.05)。各浓度hDPSC-apovs处理组的钙结节形成量均高于对照组(P<0.05);qPCR结果显示,5μg/mL、25μg/mL组Alp、Runx2、Spp1、Bglap表达均上调(P<0.05),1μg/mL组只有Alp和Runx2表达上调,0.2μg/mL组仅有Alp表达水平上调(P<0.05)。结论在本研究浓度范围内,低浓度的hDPSC-apovs对mBMSC增殖具有促进作用,高浓度则表现为抑制作用;hDPSC-apovs对于mBMSC的成骨分化有一定促进作用,且不同浓度hDPSCapovs对成骨相关基因表达的影响不同。
基金supported by the National Natural Science Foundation of China(Grant No.52088102)the Major Scientific and Technological Innovation Project of Shandong Province(Grant No.2019JZZY010820).
文摘This paper presents the design of a novel honeycomb structure with a double curved beam.The purpose of this design is to achieve vibration isolation for the main engine of an offshore platform and reduce impact loads.An analytical formula for the force-displacement relationship of the honeycomb single-cell structure is presented based on the modal superposition method.This formula provides a theoretical basis for predicting the compression performance of honeycomb structures.The effects of structural geometric parameters,series and parallel connection methods on the mechanical and energy absorption properties are investigated through mathematical modeling and experimental methods.Furthermore,the study focuses on the vibration isolation and impact resistance performance of honeycomb panels.The results show that the designed honeycomb structure has good mechanical and energy absorption performance,and its energy absorption effect is related to the geometric parameters and series and parallel connection methods of the structure.The isolation efficiency of the honeycomb with 4 rows and 3 columns reaches 38%.The initial isolation frequency of the isolator is 11.7 Hz.