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Distinct functions of Trio GEF domains in axon outgrowth of cerebellar granule neurons

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Journal of Genetics and Genomics 2019年第2期46卷 87-96页

作者： Tao Tao Jie Sun Yajing Peng Pei Wang Xin chen Wei Zhao yeqiong Li Lisha Wei Wei Wang Yanyan Zheng ye Wang Xuena Zhang Min-Sheng Zhu Model Animal Research Center State Key Laboratory of Pharmaceutical Biotechnology Department of Neurology of the Affiliated Nanjing Drum Tower Hospital of Nanjing University Medical School Nanjing University

As a critical guanine nucleotide exchange factor(GEF) regulating neurite outgrowth, Trio coordinates multiple processes of cytoskeletal dynamics through activating Rac1, Cdc42 and RhoA small GTPases by two GEF domains, but the in vivo roles of these GEF domains and corresponding downstream effectors have not been determined yet. We established multiple lines of knockout mice and assessed the respective roles of Trio GEF domains and Rac1 in axon outgrowth. Knockout of total Trio in cerebellar granule neurons(CGNs) led to an impaired F-actin rearrangement of growth cone and hence a retarded neurite outgrowth. Such a retardation was reproduced by inhibition of GEF1 domain or knockdown of Cdc42 and restored apparently by introduction of active Cdc42. As Rac1 deficiency did not affect the neurite outgrowth of CGNs, we suggested that Trio GEF1-mediated Cdc42 activation was required for neurite outgrowth. We established a GEF2-knockout line with deletion of all Trio isoforms except a cerebella-specific Trio8, a short isoform of Trio without GEF2 domain, and used this line as a GEF2-deficient animal model. The GEF2-deficient CGNs had a normal neurite outgrowth but abolished Netrin-1-promoted growth, without affecting Netrin-1 induced Rac1 activation. We thus suggested that Trio GEF1-mediated Cdc42 activation rather than Rac1 activation drives the F-actin dynamics necessary for neurite outgrowth, while GEF2 functions in Netrin-1-promoted neurite elongation. Our results delineated the distinct roles of Trio GEF domains in neurite outgrowth, which is instructive to understand the pathogenesis of clinical Trio-related neurodevelopmental disorders.

关键词： Trio GEF Rho GTPases Axon outgrowth Cerebellar granule neuron

Effects of calcium, samarium addition on microstructure and mechanical properties of AZ61 magnesium alloy

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Journal of Rare Earths 2015年第1期33卷 86-92页

作者：陈玉安金李方丹宋裕叶睿宇 College of Materials Science and Engineering Chongqing University

The microstructure and mechanical properties of AZ61 magnesium alloy with Ca, Sm addition were investigated. The results showed that the addition of 0.5 wt.% Ca reduced the quantity of Mg17Al12 phase, and formed a new Al4 Ca phase which is reticular in AZ61 alloy. With the addition of Ca and Sm, the microstructure was further refined and new Al-Sm rich phases were formed in AZ61 alloy with 0.6 wt.%-1.5 wt.% Sm addition, the TEM analysis confirmed that they were Al2 Sm and Al4 Sm. Tensile tests showed that 1.0 wt.% Sm addition contributed to the formation of the Al2 Sm and Al4 Sm and the improvement in the ambient strength, i.e., an ultimate tensile strength of 327 MPa and an elongation of 10.1%. However, excessive Sm addition led to the coarsening of Al2 Sm and Al4 Sm phases, thus resulted in the decline of strength and plasticity.

关键词： AZ61 magnesium microstructure mechanical properties samarium rare earths

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影像组学研究的文献计量学分析

中国医学装备 2024年第8期21卷 113-120页

作者：杨米扬陈楚洁汪昭楚叶培筠洪成坤张宇航付丽媛福建中医药大学福总教学医院(第九〇〇医院)放射诊断科福州350025 福建中医药大学附属人民医院肛肠科福州350004 中国人民解放军联勤保障部队第九〇〇医院放射诊断科福州350025

目的:分析2019—2023年近5年影像组学研究的发展现状、前沿及热点,为我国影像组学研究提供理论参考和指引方向。方法:检索2003年1月1日至2023年8月10日美国科学期刊网络索引(WOS)核心数据库中发表在影像组学领域的相关文献,按照纳入与... 详细信息

目的:分析2019—2023年近5年影像组学研究的发展现状、前沿及热点,为我国影像组学研究提供理论参考和指引方向。方法:检索2003年1月1日至2023年8月10日美国科学期刊网络索引(WOS)核心数据库中发表在影像组学领域的相关文献,按照纳入与排除标准筛选2003-2023年获取符合条件的文献6777篇,其中2019年1月1日至2023年8月10日近5年文献6254篇,采用文献计量学方法进行国家与地区、机构、期刊、作者和关键词进行聚类分析及可视化图谱绘制。结果:6777篇影像组学相关文献最早发表于2011年,2018年发文量趋于稳定,而后数量呈明显的逐年攀升趋势。2019年1月1日至2023年8月10日的6254篇文献中,发表于中国(3564篇)、美国(1164篇)和意大利(530篇)的发文量位居前3名,且各国合作关系紧密,美国通用电气公司发文量最多(448篇),Frontiers in Oncology(肿瘤学前沿,704篇)期刊在载文量层面排名第1。2019—2023年影像组学领域着重关注的疾病为直肠癌、肝细胞癌、乳腺癌和肺癌(尤其是非小细胞肺癌)。结论:我国虽在国家发文量上位居第一,但研究质量仍有待提升。基于多种影像检查的影像组学联合多种技术对各类疾病进行诊断与鉴别诊断、疗效预测与评估、肿瘤疾病转移情况评价与基因表型的识别是未来影像组学领域的研究趋势。

关键词：影像组学文献计量学可视化分析聚类分析

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Extracellular vesicles derived from neural EGFL-Like 1-modified mesenchymal stem cells improve acellular bone regeneration via the miR-25-5p-SMAD2 signaling axis

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Bioactive Materials 2022年第11期7卷 457-470页

作者： Yanhua Lan Huizhi Xie Qianrui Jin Xiaomin Zhao Yang Shi Yanyan Zhou Zihe Hu Yi ye Xiaoyuan Huang Yingjia Sun Zhuo chen Zhijian Xie Stomatology Hospital School of StomatologyZhejiang University School of MedicineClinical Research Center for Oral Diseases of Zhejiang ProvinceKey Laboratory of Oral Biomedical Research of Zhejiang ProvinceCancer Center of Zhejiang UniversityHangzhou310006China Department of Orthopaedics and Traumatology Li Ka Shing Faculty of MedicineThe University of Hong KongPokfulamHong Kong999077China

Stem cell based transplants effectively regenerate tissues;however, limitations such as immune rejection and teratoma formation prevent their application. Extracellular vesicles (EVs)-mediated acellular tissue regeneration is a promising alternative to stem cell based transplants. Although neural EGFL-like 1 (Nell1) is known to contribute to the osteogenic differentiation of bone marrow stem cells (BMSCs), it remains unknown whether EVs are involved in this process. Here, we present that EVs derived from Nell1-modified BMSCs (Nell1/EVs) have a stronger ability to promote BMSC osteogenesis owing to miR-25–5p downregulation. MiR-25–5p inhibits osteogenesis by targeting Smad2 and suppressing the SMAD and extracellular signal-related kinase 1 and 2 (ERK1/2) pathway activation. In addition, we demonstrate that the 3D-Nell1/EV-hydrogel system is beneficial for bone regeneration in vivo, probably stemming from a slow, continuous release and high concentration of EVs in the bone defect area. Thus, our results have shown the potential of Nell1/EVs as a novel acellular bone regeneration strategy. Mechanistically, the identification of miR-25-5p-SMAD2 signaling axis expands the knowledge of Nell1/EVs induced osteogenesis.

关键词： Extracellular vesicles Mesenchymal stem cells Bone regeneration Cell-free scaffolds miRNAs

Identification of a LMNA (c.646C>T) variant by whole-exome sequencing in combination with a dilated cardiomyopathy (DCM) related gene filter in a family with familiar DCM

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The Journal of Biomedical Research 2018年第4期32卷 314-316页

作者： Liang chen Zhongyin Zhou Huihe Lu ye Xie Gang Li Jianfei Huang Dongsheng Zhao Department of Cardiology The Second Affiliated Hospital of Nantong University Department of Cardiology The First Affiliated hospital of Hubei University of Technology Department of Cardiology The Third Affiliated Hospital of Nantong University

Dilated cardiomyopathy（DCM）is characterized by the dilated heart chambers and reduced systolic function in the absence of specific aetiology[1].Approximately one third of DCM cases are *** recent years,DCM concomita... 详细信息

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某船用齿轮箱基座的振动特性分析

装备环境工程 2024年第8期21卷 145-152页

作者：刘震叶辉陈雪华闫旭辉贾龙凯封富顺赵海涛滕德彬曾昭勇刘玉锋陈洁陈曦牟沛宋金朋重庆齿轮箱有限责任公司重庆402263 重庆开放大学智能制造与汽车学院重庆602260

目的保证船用齿轮箱在不同试验工况下的振动噪声的设计要求,对船用齿轮箱基座的振动特性进行分析。方法首先对船用齿轮箱基座进行模态分析,分析齿轮箱基座在不同阶数下有效质量与总质量的比值,同时提取不同方向下的有效质量与参与系数... 详细信息

目的保证船用齿轮箱在不同试验工况下的振动噪声的设计要求,对船用齿轮箱基座的振动特性进行分析。方法首先对船用齿轮箱基座进行模态分析,分析齿轮箱基座在不同阶数下有效质量与总质量的比值,同时提取不同方向下的有效质量与参与系数最大的模态进行分析。然后利用频响计算中的完全法对某型船用齿轮箱基座进行振动响应计算,提取3个点结果进行有限元分析,并利用锤击法对某型船用齿轮箱基座的3个测点进行机械阻抗的测试。结果通过有效质量分析,提取了前1000阶中的主要模态,分析模态发现,在齿轮箱基座的大部分区域,结构响应几乎为0,20、923、131、162、10阶出现模态为同一局部区域的模态,且23、131阶模态表现为平动及扭转振型。有限元频响计算结果表明,有限元计算结果在低频段的阻抗值更加稳定。随着频率增加,阻抗值逐渐降低,测试值的对数平均值与参考值的差值最大值为11.46 dB。计算值的对数平均值与参考值的差值最大值为10.3 dB,且逐渐接近100 dB。计算值的对数平均值与测试值对数平均值的差值均在2 dB左右。结论通过计算发现,有限元计算值接近参考值,且与参考值大多数差值均在10 dB之内。计算值与测试值接近,可以作为船用齿轮箱基座的振动噪声设计依据,为后续各型号船用齿轮箱基座优化设计打下了坚实的基础,极大提升了数字化驱动设计技术水平。

关键词：模态分析机械阻抗有限元动力学计算齿轮箱基座振动测试频响分析

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真实火灾下足尺冷成型钢复合剪力墙结构耐火性能试验研究

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建筑结构学报 2021年第6期42卷 59-71页

作者：叶继红陈文文中国矿业大学江苏省土木工程环境灾变与结构可靠性重点实验室江苏徐州221116 东南大学土木工程学院江苏南京211189

冷成型钢复合剪力墙结构采用冷成型钢管混凝土边柱、半刚性连接节点、组合楼盖体系和外填充式夹心组合墙体等构件,具有整体连接性强、抗震性能优越等优势。其耐火性能研究是该结构在我国推广应用的研究重点之一。为此,建造了3栋平面尺寸... 详细信息

冷成型钢复合剪力墙结构采用冷成型钢管混凝土边柱、半刚性连接节点、组合楼盖体系和外填充式夹心组合墙体等构件,具有整体连接性强、抗震性能优越等优势。其耐火性能研究是该结构在我国推广应用的研究重点之一。为此,建造了3栋平面尺寸为7.2 m×7.2 m、层高3 m的单层冷成型钢复合剪力墙结构模型房屋,并对其进行了不同火灾工况下的足尺结构模拟真实火灾试验。对试验现象、结构破坏模式、实际温度场和位移场进行分析。研究结果表明:相对于火源均匀分布的受火工况,存在局部集中火源的工况更容易发生轰燃;自然火灾下的小空间升温曲线对应温度改变可分为3个阶段,在封闭燃烧阶段和回燃阶段,受火房间内温度沿高度方向呈现不均匀分布,轰燃后,整个室内空间温度趋于相同;外填充式夹心组合墙体具有优越的耐火性能,自然火灾下耐火时间可以达到119 min。针对冷成型钢复合剪力墙结构提出抗火设计建议:墙体应选用外填充式夹心组合墙体;楼盖体系中,应选用与钢材连接可靠的耐火板材作为天花板,楼面ALC板材应当错落放置;需增强楼面钢托梁与墙体上部双拼梁(框架梁)连接处的防火保护。

关键词：冷成型钢复合剪力墙结构足尺结构真实火灾耐火性能升温曲线位移场

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双酶协同增加青稞慢消化淀粉含量的工艺优化

食品研究与开发 2024年第2期45卷 125-131页

作者：李岩孙康娜宋晓凡陈富章金苏宇韩丽娟叶英院珍珍青海大学农牧学院青海西宁810016 青海大学省部共建三江源生态与高原农牧业国家重点实验室青海西宁810016

以萌芽黑青稞粉为原料,研究β-淀粉酶协同α-葡萄糖苷酶增加青稞慢消化淀粉含量及其体外降糖活性。通过单因素试验、体外模拟消化法和Box-Behnken响应面试验,确定最优工艺条件,并通过α-淀粉酶和α-葡糖苷酶抑制率的测定,评价其体外降... 详细信息

以萌芽黑青稞粉为原料,研究β-淀粉酶协同α-葡萄糖苷酶增加青稞慢消化淀粉含量及其体外降糖活性。通过单因素试验、体外模拟消化法和Box-Behnken响应面试验,确定最优工艺条件,并通过α-淀粉酶和α-葡糖苷酶抑制率的测定,评价其体外降糖活性。结果表明,双酶协同增加青稞慢消化淀粉含量的酶解最优条件为β-淀粉酶、α-葡萄糖苷酶添加量150 U/g青稞粉、酶解时间8 h、酶解温度50℃、青稞粉浓度10%。此条件下青稞慢消化淀粉含量达到最高,为33.62%。体外降糖活性测定结果显示,与原粉相比酶改性青稞粉的α-淀粉酶抑制率增加了62.97%,α-葡萄糖苷酶的抑制率增加了52.46%,表明酶解粉的体外降糖活性明显提高。

关键词：青稞慢消化淀粉 β-淀粉酶 α-葡萄糖苷酶工艺优化

Geochemistry, geochronology and mineralization of the rare-metal granites in the Daping Ta-Nb deposit, Fujian Province, South China

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Acta Geologica Sinica(English Edition) 2017年第S1期91卷 289-290页

作者： WANG Jinrong HU Yongbin HUANG Shufeng chen Bin ye Yuansheng LUO Xiaohua Lv Xinbiao Faculty of Earth Resources China University of Geosciences The Second Geological Exploration Institute of China Metallurgical Geology Bureau CAS Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of Sciences

1 Introduction Rare-metal granites are widely distributed in South *** Daping porphyritic granitic Ta-Nb deposit,located in the Yongding area of south Fujian province,South China,is a large rare-metal deposit recently *** studies have been made of its petrology,mineralogy,geochemistry,chronology and *** recent years,several exploratory drillings have been done in this *** drilling holes,from 380 to 600

关键词： area In South China geochronology and mineralization of the rare-metal granites in the Daping Ta-Nb deposit Fujian Province Geochemistry Ta