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Effects of interleukin-10 treated macrophages on bone marrow mesenchymal stem cells via signal transducer and activator of transcription 3 pathway
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作者 Meng-Hao Lyu Ce Bian +3 位作者 Yi-Ping Dou Kang Gao Jun-Ji Xu Pan Ma 《World Journal of Stem Cells》 SCIE 2024年第5期560-574,共15页
BACKGROUND Alveolar bone defects caused by inflammation are an urgent issue in oral implant surgery that must be solved.Regulating the various phenotypes of macrophages to enhance the inflammatory environment can sign... BACKGROUND Alveolar bone defects caused by inflammation are an urgent issue in oral implant surgery that must be solved.Regulating the various phenotypes of macrophages to enhance the inflammatory environment can significantly affect the progression of diseases and tissue engineering repair process.AIM To assess the influence of interleukin-10(IL-10)on the osteogenic differentiation of bone marrow mesenchymal stem cells(BMSCs)following their interaction with macrophages in an inflammatory environment.METHODS IL-10 modulates the differentiation of peritoneal macrophages in Wistar rats in an inflammatory environment.In this study,we investigated its impact on the proliferation,migration,and osteogenesis of BMSCs.The expression levels of signal transducer and activator of transcription 3(STAT3)and its activated form,phos-phorylated-STAT3,were examined in IL-10-stimulated macrophages.Subsequently,a specific STAT3 signaling inhibitor was used to impede STAT3 signal activation to further investigate the role of STAT3 signaling.RESULTS IL-10-stimulated macrophages underwent polarization to the M2 type through substitution,and these M2 macrophages actively facilitated the osteogenic differentiation of BMSCs.Mechanistically,STAT3 signaling plays a crucial role in the process by which IL-10 influences macrophages.Specifically,IL-10 stimulated the activation of the STAT3 signaling pathway and reduced the macrophage inflammatory response,as evidenced by its diminished impact on the osteogenic differentiation of BMSCs.CONCLUSION Stimulating macrophages with IL-10 proved effective in improving the inflammatory environment and promoting the osteogenic differentiation of BMSCs.The IL-10/STAT3 signaling pathway has emerged as a key regulator in the macrophage-mediated control of BMSCs’osteogenic differentiation. 展开更多
关键词 MACROPHAGES INTERLEUKIN-10 Bone marrow mesenchymal stem cells Signal transducer and activator of transcription 3 Inflammatory response
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传感器在生物医学领域研究的前沿进展--TRANSDUCERS 2023国际会议综述
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作者 王耀正 张海霞 《太赫兹科学与电子信息学报》 2023年第7期959-964,共6页
2023年6月25日至6月29日,第22届国际固态传感器、执行器和微系统会议(TRANSDUCERS 2023)在日本京都召开,来自世界各地的专家学者济济一堂,分享在传感器与执行器等领域的最新研究成果。本文从可穿戴生物传感器、生物传感器后端电路和传... 2023年6月25日至6月29日,第22届国际固态传感器、执行器和微系统会议(TRANSDUCERS 2023)在日本京都召开,来自世界各地的专家学者济济一堂,分享在传感器与执行器等领域的最新研究成果。本文从可穿戴生物传感器、生物传感器后端电路和传感器在生物医学领域的应用等3个角度,详细介绍并阐述本次会议上的前沿研究成果,并对相关研究成果的研究意义与未来展望给出了总结。 展开更多
关键词 transducerS 2023 MEMS BIOMEMS 生物医学
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Photoacoustic microscopy based on transparent piezoelectric ultrasound transducers 被引量:1
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作者 Hangbing Peng Zhongwen Cheng +1 位作者 Lvming Zeng Xuanrong Ji 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2023年第5期77-92,共16页
Photoacoustic microscopy(PAM),due to its deep penetration depth and high contrast,is playing an increasingly important role in biomedical imaging.PAM imaging systems equipped with conventional ultrasound transducers h... Photoacoustic microscopy(PAM),due to its deep penetration depth and high contrast,is playing an increasingly important role in biomedical imaging.PAM imaging systems equipped with conventional ultrasound transducers have demonstrated excellent imaging performance.However,these opaque ultrasonic transducers bring some constraints to the further development and application of PAM,such as complex optical path,bulky size,and difficult to integrate with other modalities.To overcome these problems,ultrasonic transducers with high optical transparency have appeared.At present,transparent ultrasonic transducers are divided into optical-based and acoustic-based sensors.In this paper,we mainly describe the acoustic-based piezoelectric transparent transducers in detail,of which the research advances in PAM applications are reviewed.In addition,the potential challenges and developments of transparent transducers in PAM are also demonstrated. 展开更多
关键词 Photoacoustic microscopy transparent ultrasound transducer LiNbO_(3) PMN-PT PVDF CMUT
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Helical particle manipulation based on power-exponent-phase acoustic vortices generated by a sector transducer array
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作者 王青东 胡彦涛 +1 位作者 王胜利 李洪宇 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期333-341,共9页
The characteristics of traditional acoustic vortices(AVs) were verified by the cross-sectional axisymmetric pressure distributions with perfect phase spirals around the center pressure null. In order to generate a non... The characteristics of traditional acoustic vortices(AVs) were verified by the cross-sectional axisymmetric pressure distributions with perfect phase spirals around the center pressure null. In order to generate a non-axisymmetric pressure distribution, the concept of power-exponent-phase was first introduced into the formation of AV beams, named “powerexponent-phase acoustic vortices(PAVs)” in this paper. Based on a ring-array of sector transducers, the helical distribution of the low-pressure valley in cross-sections of PAVs, which enables particles to move from a distant position to the center low-potential well along a certain spiral passageway, was proved theoretically. The particle manipulation behavior for PAVs with a power order of 2 is numerically modeled and experimentally confirmed. The results show that PAVs with a nonaxisymmetric spiral pressure distribution can be used to realize the directional transport of particles in an enlarged scope,suggesting prospective application potential in biomedical engineering. 展开更多
关键词 acoustic vortices power-exponent-phase spiral potential well sector transducer array particle manipulation
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Inverse design and realization of an optical cavity-based displacement transducer with arbitrary responses
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作者 Qianbo Lu Qingxiong Xiao +6 位作者 Chengxiu Liu Yinan Wang Qixuan Zhu Manzhang Xu Xuewen Wang Xiaoxu Wang Wei Huang 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第3期12-24,共13页
Optical cavity has long been critical for a variety of applications ranging from precise measurement to spectral analysis.A number of theories and methods have been successful in describing the optical response of a s... Optical cavity has long been critical for a variety of applications ranging from precise measurement to spectral analysis.A number of theories and methods have been successful in describing the optical response of a stratified optical cavity,while the inverse problem,especially the inverse design of a displacement sensitive cavity,remains a significant challenge due to the cost of computation and comprehensive performance requirements.This paper reports a novel inverse design methodology combining the characteristic matrix method,mixed-discrete variables optimization algorithm,and Monte Carlo method-based tolerance analysis.The material characteristics are indexed to enable the mixed-discrete variables optimization,which yields considerable speed and efficiency improvements.This method allows arbitrary response adjustment with technical feasibility and gives a glimpse into the analytical characterization of the optical response.Two entirely different light-displacement responses,including an asymmetric sawtooth-like response and a highly symmetric response,are dug out and experimentally achieved,which fully confirms the validity of the method.The compact Fabry-Perot cavities have a good balance between performance and feasibility,making them promising candidates for displacement transducers.More importantly,the proposed inverse design paves the way for a universal design of optical cavities,or even nanophotonic devices. 展开更多
关键词 inverse design optical cavity displacement transducer mixed-discrete variables optimization stratified system
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Design and analysis of longitudinal–flexural hybrid transducer for ultrasonic peen forming
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作者 Wuqin Li Yongyong Zhu +4 位作者 Xiaolong Lu Huafeng Li Ying Wei Pengwei Shang Bo Feng 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2023年第4期30-39,共10页
Ultrasonic peen forming(UPF)is an emerging technology that exhibits great superiority in both its flexible operating modes and the deep residual stress that it produces compared with conventional plastic forming metho... Ultrasonic peen forming(UPF)is an emerging technology that exhibits great superiority in both its flexible operating modes and the deep residual stress that it produces compared with conventional plastic forming methods.Although ultrasonic transducers with longitudinal vibration have been widely studied,they have seldom been incorporated into UPF devices for machining in confined spaces.To meet the requirements of this type of machining,a sandwich-type piezoelectric transducer with coupled longitudinal-flexural vibrational modes is proposed.The basic structure of the transducer is designed to obtain large vibrational amplitudes in both modes.Experimental results obtained with a prototype device demonstrate the feasibility of the proposed transducer.The measured vibrational amplitude for the working face in the longitudinal vibrational mode is 1.0μm,and electrical matching increases this amplitude by 40%.The flexural vibration characteristics of the same prototype transducer are also tested and are found to be slightly smaller than those of longitudinal mode.The resultant working strokes of the UPF impact pins reach 1.7 mm and 1.2 mm in the longitudinal and flexural modes,respectively.The forming capability of the prototype has been evaluated via 15-min machining on standard 2024-T351 aluminum plates.After UPF,an improved surface morphology with lower surface roughness is obtained.The aluminum plate test piece has an apparent upper deformation with an arc height of 0.64 mm.The measured peak value of the compressive residual stress is around 250 MPa,appearing at a depth of 100μm.The proposed longitudinal-flexural hybrid transducer thus provides a high-performance tool for plate peen forming in confined spaces. 展开更多
关键词 Ultrasonic peen forming Piezoelectric transducer Longitudinal-flexural vibrational mode Modal analysis
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18β-glycyrrhetinic acid promotes gastric cancer cell autophagy and inhibits proliferation by regulating miR-328-3p/signal transducer and activator of transcription 3
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作者 Yi Yang Yi Nan +7 位作者 Yu-Hua Du Shi-Cong Huang Dou-Dou Lu Jun-Fei Zhang Xia Li Yan Chen Lei Zhang Ling Yuan 《World Journal of Gastroenterology》 SCIE CAS 2023年第27期4317-4333,共17页
BACKGROUND Gastric cancer(GC)is one of the most common cancer types worldwide,and its prevention and treatment methods have garnered much attention.As the active ingredient of licorice,18β-glycyrrhetinic acid(18β-GR... BACKGROUND Gastric cancer(GC)is one of the most common cancer types worldwide,and its prevention and treatment methods have garnered much attention.As the active ingredient of licorice,18β-glycyrrhetinic acid(18β-GRA)has a variety of pharmacological effects.The aim of this study was to explore the effective target of 18β-GRA in the treatment of GC,in order to provide effective ideas for the clinical prevention and treatment of GC.AIM To investigate the mechanism of 18β-GRA in inhibiting cell proliferation and promoting autophagy flux in GC cells.METHODS Whole transcriptomic analyses were used to analyze and screen differentially expressed microRNAs(miRNAs)in GC cells after 18β-GRA intervention.Lentivirus-transfected GC cells and the Cell Counting Kit-8 were used to detect cell proliferation ability,cell colony formation ability was detected by the clone formation assay,and flow cytometry was used to detect the cell cycle and apoptosis.A nude mouse transplantation tumor model of GC cells was constructed to verify the effect of miR-328-3p overexpression on the tumorigenicity of GC cells.Tumor tissue morphology was observed by hematoxylin and eosin staining,and microtubule-associated protein light chain 3(LC3)expression was detected by immunohistochemistry.TransmiR,STRING,and miRWalk databases were used to predict the relationship between miR-328-3p and signal transducer and activator of transcription 3(STAT3)-related information.Expression of STAT3 mRNA and miR-328-3p was detected by quantitative polymerase chain reaction(qPCR)and the expression levels of STAT3,phosphorylated STAT3(p-STAT3),and LC3 were detected by western blot analysis.The targeted relationship between miR-328-3p and STAT3 was detected using the dual-luciferase reporter gene system.AGS cells were infected with monomeric red fluorescent protein-green fluorescent protein-LC3 adenovirus double label.LC3 was labeled and autophagy flow was observed under a confocal laser microscope.RESULTS The expression of miR-328-3p was significantly upregulated after 18β-GRA intervention in AGS cells(P=4.51E-06).Overexpression of miR-328-3p inhibited GC cell proliferation and colony formation ability,arrested the cell cycle in the G0/G1 phase,promoted cell apoptosis,and inhibited the growth of subcutaneous tumors in BALB/c nude mice(P<0.01).No obvious necrosis was observed in the tumor tissue in the negative control group(no drug intervention or lentivirus transfection)and vector group(the blank vector for lentivirus transfection),and more cells were loose and necrotic in the miR-328-3p group.Bioinformatics tools predicted that miR-328-3p has a targeting relationship with STAT3,and STAT3 was closely related to autophagy markers such as p62.After overexpressing miR-328-3p,the expression level of STAT3 mRNA was significantly decreased(P<0.01)and p-STAT3 was downregulated(P<0.05).The dual-luciferase reporter gene assay showed that the luciferase activity of miR-328-3p and STAT33’untranslated regions of the wild-type reporter vector group was significantly decreased(P<0.001).Overexpressed miR-328-3p combined with bafilomycin A1(Baf A1)was used to detect the expression of LC3 II.Compared with the vector group,the expression level of LC3 II in the overexpressed miR-328-3p group was downregulated(P<0.05),and compared with the Baf A1 group,the expression level of LC3 II in the overexpressed miR-328-3p+Baf A1 group was upregulated(P<0.01).The expression of LC3 II was detected after intervention of 18β-GRA in GC cells,and the results were consistent with the results of miR-328-3p overexpression(P<0.05).Additional studies showed that 18β-GRA promoted autophagy flow by promoting autophagosome synthesis(P<0.001).qPCR showed that the expression of STAT3 mRNA was downregulated after drug intervention(P<0.05).Western blot analysis showed that the expression levels of STAT3 and p-STAT3 were significantly downregulated after drug intervention(P<0.05).CONCLUSION 18β-GRA promotes the synthesis of autophagosomes and inhibits GC cell proliferation by regulating the miR-328-3p/STAT3 signaling pathway. 展开更多
关键词 18β-glycyrrhetinic acid miR-328-3p Signal transducer and activator of transcription 3 Cell proliferation Autophagy flow
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Inner damage identification and residual strength assessment of a 3D printed tunnel with marble-like cementitious materials using piezoelectric transducers
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作者 Guowei Ma Chen Huang Junfei Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期838-851,共14页
Quantitative damage identification of surrounding rock is important to assess the current condition and residual strength of underground tunnels.In this work,an underground tunnel model with marble-like cementitious m... Quantitative damage identification of surrounding rock is important to assess the current condition and residual strength of underground tunnels.In this work,an underground tunnel model with marble-like cementitious materials was first fabricated using the three-dimensional(3D)printing technique and then loaded to simulate its failure mode in the laboratory.Lead zirconate titanate piezoelectric(PZT)transducers were embedded in the surrounding rock around the tunnel in the process of 3D printing.A 3D monitoring network was formed to locate damage areas and evaluate damage extent during loading.Results show that as the load increased,main cracks firstly appeared above the tunnel roof and below the floor,and then they coalesced into the tunnel boundary.Finally,the tunnel model was broken into several parts.The resonant frequency and the peak of the conductance signature firstly shifted rightwards with loading due to the sealing of microcracks,and then shifted backwards after new cracks appeared.An overall increase in the root-mean-square deviation(RMSD)calculated from conductance signatures of all the PZT transducers was observed as the load(damage)increased.Damage-dependent equivalent stiffness parameters(ESPs)were calculated from the real and imaginary signatures of each PZT at different damage states.Satisfactory agreement between equivalent and experimental ESP values was achieved.Also,the relationship between the change of the ESP and the residual strength was obtained.The method paves the way for damage identification and residual strength estimation of other 3D printed structures in civil engineering. 展开更多
关键词 Piezoelectric(PZT)transducers Three-dimensional(3D)printed tunnel Electro-mechanical impedance(EMI) method Equivalent stiffness parameter(ESP) Residual strength
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STAT3在阿尔茨海默病小鼠认知障碍发生发展中的作用及机制研究 被引量:2
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作者 王珏 陈佩弦 +1 位作者 何玲 孙逸 《中南药学》 CAS 2024年第1期17-23,共7页
目的 研究信号传导及转录激活因子3(STAT3)在阿尔茨海默病小鼠认知障碍发生发展中的作用及机制。方法 利用C57BL/6J小鼠双侧海马脑立体定位注射β-淀粉样蛋白建立阿尔茨海默病模型,给予STAT3抑制剂氯硝柳胺,运用动物行为学分析检测、Wes... 目的 研究信号传导及转录激活因子3(STAT3)在阿尔茨海默病小鼠认知障碍发生发展中的作用及机制。方法 利用C57BL/6J小鼠双侧海马脑立体定位注射β-淀粉样蛋白建立阿尔茨海默病模型,给予STAT3抑制剂氯硝柳胺,运用动物行为学分析检测、Western blot分析检测等探究STAT3在认知障碍中的作用及机制。结果 行为学实验表明,与模型组小鼠相比,给药组小鼠的焦虑症状、空间探索能力、物体识别能力和学习记忆能力均得到改善;Western blot分析结果表明,给药后小鼠阿尔茨海默病的病理标志物改善,促炎因子表达下调;试剂盒分析结果显示给药组小鼠氧化应激相关指标改善;HE染色结果显示给药组小鼠海马神经元组织形态的改善。结论 本研究初步证明了抑制STAT3可减轻神经炎症和氧化应激,从而改善阿尔茨海默病小鼠的认知障碍。 展开更多
关键词 阿尔茨海默病 神经炎症 信号传导及转录激活因子3 氯硝柳胺
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镍铬硅薄膜换能元的制备及其发火性能研究
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作者 任小明 姚洪志 +3 位作者 解瑞珍 刘红娥 王燕兰 王可暄 《火工品》 CAS CSCD 北大核心 2024年第5期42-45,共4页
为了探索镍铬硅薄膜换能元的发火性能,采用MEMS工艺制备了镍铬硅薄膜换能元。利用扫描电子显微镜(SEM)和四探针法对镍铬硅薄膜进行了性能表征;依据GJB/Z 377B-2022感度实验中兰利法进行了镍铬硅薄膜换能元感度测试;在发火电压27 V、发... 为了探索镍铬硅薄膜换能元的发火性能,采用MEMS工艺制备了镍铬硅薄膜换能元。利用扫描电子显微镜(SEM)和四探针法对镍铬硅薄膜进行了性能表征;依据GJB/Z 377B-2022感度实验中兰利法进行了镍铬硅薄膜换能元感度测试;在发火电压27 V、发火电容33μF条件下对镍铬硅薄膜换能元进行了发火性能测试。结果表明:镍铬硅薄膜表面平整、致密性较好,且具有负电阻温度系数,其换能元平均发火电压比镍铬薄膜换能元高;镍铬硅薄膜换能元作用过程中产生等离子体,瞬发度高。 展开更多
关键词 薄膜换能元 镍铬硅 MEMS 性能表征 发火性能
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基于声黑洞设计理论的径向夹心式径-弯复合换能器
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作者 刘洋 陈诚 林书玉 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第8期159-168,共10页
基于弯曲波在声黑洞(acoustic black hole,ABH)结构中振幅不断增大的特性,提出了一种新型径向夹心式径-弯复合换能器,该换能器由径向夹心式圆环换能器与外围的环形ABH结构组成.ABH结构的存在实现了换能器径向振动与弯曲振动之间的转换,... 基于弯曲波在声黑洞(acoustic black hole,ABH)结构中振幅不断增大的特性,提出了一种新型径向夹心式径-弯复合换能器,该换能器由径向夹心式圆环换能器与外围的环形ABH结构组成.ABH结构的存在实现了换能器径向振动与弯曲振动之间的转换,提高了换能器的声辐射性能.利用几何声学的方法建立了ABH结构弯曲振动的解析模型,给出了其弯曲振动的本征频率,并结合有限元方法讨论了换能器机电转换性能随尺寸变化的关系.通过有限元方法给出了该换能器在空气中的辐射声压场、辐射声强以及辐射指向性,仿真结果表明,ABH结构的存在能够改善换能器弯曲振动的机电转换性能,提高换能器的声辐射性能,使换能器呈现出一定的辐射指向性.最后通过实验对换能器样机的电阻抗特性以及振动模态进行测量,实验结果与仿真相符合. 展开更多
关键词 声黑洞 换能器 径向振动 弯曲振动
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磁耦合式可调频压电振动俘能器
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作者 王淑云 杜洁雅 +3 位作者 黄喆人 阚君武 柴超辉 张忠华 《光学精密工程》 EI CAS CSCD 北大核心 2024年第1期73-83,共11页
为提高压电振动俘能器的环境适应性,提出一种磁耦合式可调频压电振动俘能器,利用激励器上主动磁铁和组合换能器上被动磁铁间的耦合作用及横摆簧片实现压电振子的单向限幅激励。通过对俘能器及磁对的建模和仿真分析,获得了俘能器结构参... 为提高压电振动俘能器的环境适应性,提出一种磁耦合式可调频压电振动俘能器,利用激励器上主动磁铁和组合换能器上被动磁铁间的耦合作用及横摆簧片实现压电振子的单向限幅激励。通过对俘能器及磁对的建模和仿真分析,获得了俘能器结构参数对俘能器输出性能的影响,在此基础上制作俘能器样机并进行实验研究,获得了俘能器纵摆质量m_(1)、横摆质量m_(2)、横向距离Lx、纵向距离Ly、竖向距离Lz及负载电阻对俘能器输出性能的影响规律。结果表明:存在两阶谐振频率f_(1)和f_(2)使输出电压出现峰值U_(n1)和U_(n2),调节m_(1),m_(2),Lx,Ly及Lz会影响f_(1),f_(2),U_(n1)及U_(n2);其他条件一定时,存在最佳负载电阻2 200 kΩ使输出功率达到0.122 mW。通过选择合适的结构参数能够提升俘能器的有效频带和输出电压,对增强压电振动俘能器的可靠性和频率适应性具有一定的参考价值。 展开更多
关键词 压电 可调频 磁耦合 组合换能器 能量回收
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先天性肠闭锁患儿组织STAT3和血清STAT3 mRNA,IL-12p40,IL-13Rα2水平表达及与预后的相关性研究
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作者 董彦清 牛会忠 +4 位作者 张鹏举 任慧 陈盼 张治广 牛波波 《现代检验医学杂志》 CAS 2024年第5期35-40,46,共7页
目的探究先天性肠闭锁(congenital intestinal atresia)患儿组织信号传导与转录激活因子3(signal transducerand activator of transcription 3,STAT3)和血清STAT3 mRNA,IL-12p40及IL-13Rα2水平表达及与预后的相关性。方法收集2020年1... 目的探究先天性肠闭锁(congenital intestinal atresia)患儿组织信号传导与转录激活因子3(signal transducerand activator of transcription 3,STAT3)和血清STAT3 mRNA,IL-12p40及IL-13Rα2水平表达及与预后的相关性。方法收集2020年1月~2023年1月在河北省儿童医院进行治疗的先天性肠闭锁患儿术中切除的100例肠闭锁病变组织、正常肠管组织及术前血清样本,根据Grosfeld分型标准将患儿分为Ⅰ型39例,Ⅱ型22例,Ⅲ型30例和Ⅳ型9例。根据术后6个月的恢复情况,将患儿分为预后良好组(n=78)和预后不良组(n=22);并选取93例同期体检健康儿童的血清样本作为对照。免疫组织化学检测STAT3在组织中阳性表达及定位情况;Western blot检测组织中STAT3蛋白表达;荧光定量PCR法(qPCR)检测血清中STAT3 mRNA的表达水平。采用Pearson相关分析先天性肠闭锁患儿血清STAT3与炎症因子水平的相关性。采用Logistic回归分析影响先天性肠闭锁患儿预后的因素。利用受试者工作特征(ROC)曲线分析血清STAT3水平对先天性肠闭锁患儿预后的预测效能。结果免疫组织化学结果显示,STAT3阳性表达主要定位于细胞质和细胞核,先天性肠闭锁组织中的阳性表达率(86%)显著高于正常肠管组织(18%),差异具有统计学意义(χ^(2)=92.628,P<0.05)。Western blot结果显示STAT3在先天性肠闭锁组织中的相对表达量(1.59±0.21)显著高于正常肠管组织中的相对表达水平(0.81±0.12),差异具有统计学意义(t=30.567,P<0.05)。qPCR法结果显示先天性肠闭锁组患儿血清STAT3 mRNA(2.13±0.56),IL-12p40(0.89±0.13ng/ml)以及IL-13Rα2(6.42±1.86ng/ml)水平均显著高于对照组(1.06±0.11,0.37±0.08ng/ml,1.35±0.41ng/ml),差异具有统计学意义(t=18.101,33.170,25.708,均P<0.05)。随着患儿分型的增加,STAT3 mRNA及IL-12p40,IL-13Rα2水平逐渐增加,差异具有统计学意义(F=52.666,160.300,25.82,均P<0.05)。Pearson相关分析显示先天性肠闭锁患儿血清STAT3 mRNA与炎症因子IL-12p40,IL-13Rα2水平均呈显著正相关(r=0.496,0.564,均P<0.001)。先天性肠闭锁患儿预后不良组血清STAT3 mRNA(3.01±0.75)表达水平显著高于预后良好组(1.88±0.51),差异具有统计学意义(t=8.212,P<0.05)。Logistic回归分析结果显示,STAT3 mRNA,IL-12p40,IL-13Rα2水平以及低出生质量均是先天性肠闭锁患儿预后不良的独立危险因素(均P<0.05)。ROC曲线可知血清STAT3评估先天性肠闭锁患儿预后的曲线下面积(AUC)为0.916,敏感度和特异度分别为81.82%,88.46%,当血清STAT3 mRNA水平高于2.47时先天性肠闭锁患儿发生预后不良的几率较高。结论STAT3在先天性肠闭锁患儿组织和血清中的表达显著升高,血清STAT3对患儿预后情况具有一定的预测价值。 展开更多
关键词 先天性肠闭锁 信号传导与转录激活因子3
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纤维介素2在卵巢癌中的表达及其对SKOV3细胞生物学特性的影响
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作者 王新玲 李楠 +4 位作者 赵武杰 王斌 王雅卓 范静 李娜 《现代中西医结合杂志》 CAS 2024年第12期1642-1647,1665,共7页
目的 探讨纤维介素2(FGL2)在上皮性卵巢癌中的表达情况及其对人卵巢癌SKOV3细胞生物学特性的影响及相关机制。方法 (1)取2018年7月—2020年5月在河北省人民医院行手术治疗的40例浆液性卵巢癌以及16例卵巢浆液性囊腺瘤患者的切除组织标本... 目的 探讨纤维介素2(FGL2)在上皮性卵巢癌中的表达情况及其对人卵巢癌SKOV3细胞生物学特性的影响及相关机制。方法 (1)取2018年7月—2020年5月在河北省人民医院行手术治疗的40例浆液性卵巢癌以及16例卵巢浆液性囊腺瘤患者的切除组织标本,免疫组化法检测组织标本中FGL2蛋白表达情况。(2)取SKOV3细胞,实验设空白组、FGL2 siRNA转染组和阴性对照siRNA组,采用Western blot法检测细胞中FGL2蛋白表达情况,以确定FGL2 siRNA转染效率;后续通过CCK-8法以及Transwell实验检测FGL2 siRNA转染组和阴性对照siRNA组SKOV3细胞增殖、侵袭及迁移能力,Western blot法检测细胞中白细胞介素-6(IL-6)、信号转导和转录激活因子3(STAT3)蛋白表达情况,观察沉默FGL2对SKOV3细胞增殖、侵袭及迁移能力和IL-6/STAT3信号通路的影响。结果 浆液性卵巢癌患者组织标本中FGL2蛋白高表达率明显高于卵巢浆液性囊腺瘤患者[80.0%(32/40)比37.5%(6/16),P<0.05]。FGL2 siRNA转染组FGL2蛋白相对表达量明显低于阴性对照siRNA组(P<0.05);FGL2 siRNA转染组转染后48 h、72 h、96 h、120 h的SKOV3细胞增殖活性均明显低于同期阴性对照siRNA组(P均<0.05);Transwell加基质胶侵袭实验和不加基质胶迁移实验显示FGL2 siRNA转染组穿膜细胞数均明显少于阴性对照siRNA组(P均<0.05);FGL2 siRNA组IL-6和p-STAT3蛋白相对表达量均明显低于阴性对照siRNA组(P均<0.05)。结论 卵巢癌组织中存在FGL2高表达,沉默FGL2抑制IL-6/STAT3信号通路的活性可影响卵巢癌细胞的生物学特性,推测FGL2可作为卵巢癌诊治的靶点之一。 展开更多
关键词 卵巢癌 纤维介素2 侵袭 迁移 白细胞介素-6 信号转导和转录激活因子3
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热声制冷机中磁致伸缩换能器设计及特性分析
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作者 汪建新 宋春雨 +2 位作者 孟楠 范蒙洋 李昭钦 《兵器材料科学与工程》 CAS CSCD 北大核心 2024年第6期8-14,共7页
本文针对传统驱动方式热声制冷机效率低的问题,提出一种用磁致伸缩换能器驱动热声制冷机的设计方案。磁致伸缩换能器作为热声制冷机的驱动器,其输出特性对热声制冷机制冷效果至关重要。基于此对磁致伸缩换能器开展了从超磁致伸缩材料几... 本文针对传统驱动方式热声制冷机效率低的问题,提出一种用磁致伸缩换能器驱动热声制冷机的设计方案。磁致伸缩换能器作为热声制冷机的驱动器,其输出特性对热声制冷机制冷效果至关重要。基于此对磁致伸缩换能器开展了从超磁致伸缩材料几何参数、激励线圈最佳电磁转换效率和内部磁路3个方面的优化设计研究,最后对换能器输出特性进行了仿真分析。结果表明:在4.6 kHz时位移最大,输出位移达到63μm,满足驱动热声制冷机需求。 展开更多
关键词 超磁致伸缩换能器 结构设计 有限元分析 输出特性
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用于血管内超声成像的高频换能器研制
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作者 李霞 陈益良 苏敏 《声学技术》 CSCD 北大核心 2024年第1期142-146,共5页
血管内超声(Intravascular Ultrasound,IVUS)成像技术可以精确评估血管腔口径、血管壁形态和其他相关血流和血管特性,在冠状动脉疾病的诊断、治疗指导和治疗后的评估中发挥着重要作用。文章设计并制备了一种用于血管内超声成像的高频超... 血管内超声(Intravascular Ultrasound,IVUS)成像技术可以精确评估血管腔口径、血管壁形态和其他相关血流和血管特性,在冠状动脉疾病的诊断、治疗指导和治疗后的评估中发挥着重要作用。文章设计并制备了一种用于血管内超声成像的高频超声换能器,并对换能器的电学和声学性能进行测试和表征。结果表明,所制备IVUS换能器的中心频率为38.9 MHz,-6 dB相对带宽为56.6%,在谐振频率42.3 MHz处的电阻抗为22.6Ω,在反谐振频率48.2MHz处的电阻抗为56.5Ω,有效机电耦合系数为0.48。使用该换能器进行线仿体成像实验的结果显示,换能器的纵向分辨率为54μm,横向分辨率为209μm。最后,将文中制备的超声换能器与国外同类型换能器进行比较,结果表明,该换能器的性能良好,能够满足血管内超声临床检测需求,未来有望能够突破技术瓶颈,实现国产替代。 展开更多
关键词 心血管疾病 血管内超声成像 高频超声换能器
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基于多层石墨烯薄膜的柔性传感器研究
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作者 李正农 肖康博 任志刚 《仪表技术与传感器》 CSCD 北大核心 2024年第6期1-7,65,共8页
为了在结构监测领域探索新型的传感材料和技术,对一种以多层石墨烯薄膜作为敏感材料的柔性传感器展开了研究,进行结构应变和冲击力信号监测。基于相似三角形的性质,设计了柔性传感器大应变范围内的标定实验,并通过悬臂钢梁实验对柔性传... 为了在结构监测领域探索新型的传感材料和技术,对一种以多层石墨烯薄膜作为敏感材料的柔性传感器展开了研究,进行结构应变和冲击力信号监测。基于相似三角形的性质,设计了柔性传感器大应变范围内的标定实验,并通过悬臂钢梁实验对柔性传感器和电阻应变片的应变监测结果进行了比较。此外,还搭建了沙粒冲击实验平台,实现了沙粒在不同下落高度的冲击响应。实验结果表明:柔性传感器具有大变形的监测能力,可代替电阻应变片测量结构的应变,并可用于沙粒冲击力的测量,在结构监测领域具有广泛的应用前景。 展开更多
关键词 石墨烯薄膜 传感器标定 应变监测 沙粒冲击力
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岩土离心模型试验软接触式微型土压计研制及性能评价
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作者 王永志 杨阳 +4 位作者 徐光明 汤兆光 张雪东 孙锐 周燕国 《岩土工程学报》 EI CAS CSCD 北大核心 2024年第8期1655-1664,共10页
微型土压计是岩土离心模型试验的重要测量技术之一。为解决刚性土压计测量中拱效应、尺寸效应、厚径比等经典误差问题及提升频响速率和精度,尝试开发了一种全新软接触式微型土压计ESP-II,介绍了其技术创新和设计方法。以两种国际代表性... 微型土压计是岩土离心模型试验的重要测量技术之一。为解决刚性土压计测量中拱效应、尺寸效应、厚径比等经典误差问题及提升频响速率和精度,尝试开发了一种全新软接触式微型土压计ESP-II,介绍了其技术创新和设计方法。以两种国际代表性土压计为参考,设计开展一系列离心模型试验,对其感应精度、速率和适用性进行评价。主要结论:①逐级加载离心加速度5g~50g试验下,各深度ESP-II和两种参考传感器测试结果与理论值的平均误差分别为5.16%,6.70%,4.85%,三者沿深度拟合K_(0)优度系数R^(2)均≥0.9893。②脉冲荷载试验中ESP-II最大响应时间约7.8 ms,略优于两种参考传感器,具有良好的频响速率。③不同幅值正弦、地震等动荷载试验下,3种传感器测得土压力均呈一致增量趋势,K_(0)约由0.43~0.45增至0.51~0.56,与既有规律认识吻合。④离心机下降卸荷过程中,ESP-II测得时程表现良好连续性和光滑性,反映软接触式设计有利于保障土体与传感器良好接触和稳定响应。研究成果,初步证明了软接触式土压计适应于静、动力离心试验需求,具有重要价值与应用前景。 展开更多
关键词 岩土离心模型试验 微型土压计 设计方法 软接触式 性能评价
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宫颈癌组织中KLF12、STAT3的表达及其与临床病理特征和预后的相关性
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作者 何永亮 章培 +4 位作者 吴宁 蒋炳林 成永莲 欧阳海英 涂媛 《现代肿瘤医学》 CAS 2024年第7期1305-1310,共6页
目的:分析宫颈癌中Krüpple样转录因子12(KLF12),信号转导和转录激活因子3(STAT3)的表达,并探讨其与临床病理特征和预后的相关性。方法:收集2017年07月至2020年07月收治于本院的82例宫颈癌患者活检及手术宫颈癌标本。采用免疫组化... 目的:分析宫颈癌中Krüpple样转录因子12(KLF12),信号转导和转录激活因子3(STAT3)的表达,并探讨其与临床病理特征和预后的相关性。方法:收集2017年07月至2020年07月收治于本院的82例宫颈癌患者活检及手术宫颈癌标本。采用免疫组化法检测患者宫颈癌组织及宫颈癌KLF12、STAT3表达情况。通过χ^(2)检验分析KLF12、STAT3表达与宫颈癌患者临床病理特征的关系。采用多因素Cox回归分析宫颈癌患者预后的相关因素。绘制Kaplan-Meier曲线分析KLF12、STAT3表达与宫颈癌患者3年生存率的关系。结果:宫颈癌组织KLF12阳性表达率高于癌旁组织(P<0.05),STAT3阳性表达率高于癌旁组织(P<0.05)。不同年龄、产次、月经状态、肿瘤直径、组织学分类、浸润深度患者宫颈癌组织中KLF12、STAT3表达差异无统计学意义(P>0.05)。FIGO分期Ⅱ期、低分化、有淋巴结转移的宫颈癌患者组织中KLF12、STAT3阳性表达率较高(P<0.05)。多因素Cox回归分析显示,FIGO分期Ⅱ期、KLF12、STAT3阳性表达均是宫颈癌患者3年内死亡的独立危险因素(P<0.05)。Kaplan-Meier曲线结果显示,KLF12阳性表达患者3年生存率66.66%(28/42)低于KLF12阴性表达患者90.00%(36/40)(P<0.05),STAT3阳性表达患者3年生存率70.49%(43/61)低于STAT3阴性表达患者100%(21/21)(P<0.05)。结论:宫颈癌组织中KLF12、STAT3阳性表达升高,两者异常表达与FIGO分期、分化程度、淋巴结转移及预后有关,可作为用于评估预后的生物标志物。 展开更多
关键词 宫颈癌 KLF12基因 信号转导和转录激活因子3 临床病理特征 预后
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STAT3信号通路在神经退行性疾病中的研究进展
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作者 王珏 陈佩弦 +1 位作者 何玲 孙逸 《中南药学》 CAS 2024年第1期6-16,共11页
信号传导及转录激活蛋白3(STAT3)信号通路是机体重要的信号通路,大量体内外研究显示该通路与神经退行性疾病密切相关,其激活引发的神经炎症等在疾病的发生发展中起着重要作用。在阿尔茨海默病和帕金森病中,多项生理生化研究显示STAT3信... 信号传导及转录激活蛋白3(STAT3)信号通路是机体重要的信号通路,大量体内外研究显示该通路与神经退行性疾病密切相关,其激活引发的神经炎症等在疾病的发生发展中起着重要作用。在阿尔茨海默病和帕金森病中,多项生理生化研究显示STAT3信号通路在患者体内激活并与多项病理特征存在潜在联系,但其具体作用还存在争议;关于STAT3在其他神经退行性疾病(如血管性痴呆、亨廷顿病、肌萎缩侧索硬化、多发性硬化)的病理生理作用的研究较少,大多集中于药效研究,有待进一步探索发现。本文对STAT3信号通路在神经退行性疾病中的作用进行综述,并列举靶向STAT3药物的最新研究进展,旨在为治疗该类疾病提供有潜力的新靶点。 展开更多
关键词 信号传导及转录激活蛋白3 神经炎症 神经退行性疾病
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