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Effects of P301L-TAU on post-translational modifications of microtubules in human iPSC-derived cortical neurons and TAU transgenic mice
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作者 Mohamed Aghyad Al Kabbani Christoph Köhler Hans Zempel 《Neural Regeneration Research》 SCIE CAS 2025年第8期2348-2360,共13页
TAU is a microtubule-associated protein that promotes microtubule assembly and stability in the axon.TAU is missorted and aggregated in an array of diseases known as tauopathies.Microtubules are essential for neuronal... TAU is a microtubule-associated protein that promotes microtubule assembly and stability in the axon.TAU is missorted and aggregated in an array of diseases known as tauopathies.Microtubules are essential for neuronal function and regulated via a complex set of post-translational modifications,changes of which affect microtubule stability and dynamics,microtubule interaction with other proteins and cellular structures,and mediate recruitment of microtubule-severing enzymes.As impairment of microtubule dynamics causes neuronal dysfunction,we hypothesize cognitive impairment in human disease to be impacted by impairment of microtubule dynamics.We therefore aimed to study the effects of a disease-causing mutation of TAU(P301L)on the levels and localization of microtubule post-translational modifications indicative of microtubule stability and dynamics,to assess whether P301L-TAU causes stability-changing modifications to microtubules.To investigate TAU localization,phosphorylation,and effects on tubulin post-translational modifications,we expressed wild-type or P301L-TAU in human MAPT-KO induced pluripotent stem cell-derived neurons(i Neurons)and studied TAU in neurons in the hippocampus of mice transgenic for human P301L-TAU(p R5 mice).Human neurons expressing the longest TAU isoform(2N4R)with the P301L mutation showed increased TAU phosphorylation at the AT8,but not the p-Ser-262 epitope,and increased polyglutamylation and acetylation of microtubules compared with endogenous TAU-expressing neurons.P301L-TAU showed pronounced somatodendritic presence,but also successful axonal enrichment and a similar axodendritic distribution comparable to exogenously expressed 2N4R-wildtype-TAU.P301L-TAU-expressing hippocampal neurons in transgenic mice showed prominent missorting and tauopathy-typical AT8-phosphorylation of TAU and increased polyglutamylation,but reduced acetylation,of microtubules compared with non-transgenic littermates.In sum,P301L-TAU results in changes in microtubule PTMs,suggestive of impairment of microtubule stability.This is accompanied by missorting and aggregation of TAU in mice but not in i Neurons.Microtubule PTMs/impairment may be of key importance in tauopathies. 展开更多
关键词 human induced pluripotent stem cell MICROTUBUlES p301l pR5 mice TAU TAUOpATHY tubulin code
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Loss-of-function mutations of microRNA-142-3p promote ASH1L expression to induce immune evasion and hepatocellular carcinoma progression
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作者 Xing-Hui Yu Yan Xie +8 位作者 Jian Yu Kun-Ning Zhang Zhou-Bo Guo Di Wang Zhao-Xian Li Wei-Qi Zhang Yu-Ying Tan Li Zhang Wen-Tao Jiang 《World Journal of Gastroenterology》 SCIE CAS 2025年第1期126-145,共20页
BACKGROUND Hepatocellular carcinoma(HCC)has been a pervasive malignancy throughout the world with elevated mortality.Efficient therapeutic targets are beneficial to treat and predict the disease.Currently,the exact mo... BACKGROUND Hepatocellular carcinoma(HCC)has been a pervasive malignancy throughout the world with elevated mortality.Efficient therapeutic targets are beneficial to treat and predict the disease.Currently,the exact molecular mechanisms leading to the progression of HCC are still unclear.Research has shown that the microRNA-142-3p level decreases in HCC,whereas bioinformatics analysis of the cancer genome atlas database shows the ASH1L expression increased among liver tumor tissues.In this paper,we will explore the effects and mechanisms of microRNA-142-3p and ASH1L affect the prognosis of HCC patients and HCC cell bioactivity,and the association between them.AIM To investigate the effects and mechanisms of microRNA-142-3p and ASH1L on the HCC cell bioactivity and prognosis of HCC patients.METHODS In this study,we grouped HCC patients according to their immunohistochemistry results of ASH1L with pathological tissues,and retrospectively analyzed the prognosis of HCC patients.Furthermore,explored the roles and mechanisms of microRNA-142-3p and ASH1L by cellular and animal experiments,which involved the following experimental methods:Immunohistochemical staining,western blot,quantitative real-time-polymerase chain reaction,flow cytometric analysis,tumor xenografts in nude mice,etc.The statistical methods involved in this study contained t-test,one-way analysis of variance,theχ^(2)test,the Kaplan-Meier approach and the log-rank test.RESULTS In this study,we found that HCC patients with high expression of ASH1L possess a more recurrence rate as well as a decreased overall survival rate.ASH1L promotes the tumorigenicity of HCC and microRNA-142-3p exhibits reduced expression in HCC tissues and interacts with ASH1L through targeting the ASH1L 3′untranslated region.Furthermore,microRNA-142-3p promotes apoptosis and inhibits proliferation,invasion,and migration of HCC cell lines in vitro via ASH1L.For the exploration mechanism,we found ASH1L may promote an immunosuppressive microenvironment in HCC and ASH1L affects the expression of the cell junction protein zonula occludens-1,which is potentially relevant to the immune system.CONCLUSION Loss function of microRNA-142-3p induces cancer progression and immune evasion through upregulation of ASH1L in HCC.Both microRNA-142-3p and ASH1L can feature as new biomarker for HCC in the future. 展开更多
关键词 Hepatocellular carcinoma MicroRNA-142-3p ASH1l Immune evasion Tumor immune microenvironment Apoptosis
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Rapid Propagation of Pteris vittata L.via Tissue Culture 被引量:2
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作者 罗利琼 张军 +1 位作者 罗旭 杨兵 《Agricultural Science & Technology》 CAS 2012年第1期68-70,共3页
[Objective] The study had developed a means of rapid propagation Pteris vittata L.by tissue culture. The species was a perennial fern belonging to the genus Pteris. [Metbed] The leaf bud of P. vittata collected in fie... [Objective] The study had developed a means of rapid propagation Pteris vittata L.by tissue culture. The species was a perennial fern belonging to the genus Pteris. [Metbed] The leaf bud of P. vittata collected in field conditions as explantsand the 1/2 MS + 3% sucrose + 0.7% agar as the basic medium were used to screen the medium formula of the phytohormone ratio for callus induction and subculture of P. vittata. [Result] The best medium formula for each step was list below: 1/2 MS + 3% sucrose + 0.7% agar + 0.5 g/L PVP + 0.1 mg/L KT + 0.5 mg/L 2, 4-D for in- ducing the callus from explants; 1/2MS + 3% sucrose + 0.7% agar + 0.5 g/L PVP + 1.0 mg/L KT + 0.01 mg/L 2,4-D for inducing the GGB from callus and the seedlings from GGB. In addition, 1/2 MS + 3% sucrose + 0.7% agar + 0.5 g/L PVP + 0.5 mg/L 2,4-D for the subculture could make the continued proliferation of callus. [Cen- clusioa] This study makes an applicable procedure by the direct use of field materi- als, for propagating P. vittata in a simplified and rapid mode. 展开更多
关键词 DIFFERENTIATION pHYTOHORMONE plant tissue culture pteris vittata l.
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非小细胞肺癌EGFR基因少见突变P733L对第1代和第3代EGFR-TKI敏感性的研究
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作者 车娟娟 王婧 +3 位作者 甄洪超 林海珊 尚昆 俞静 《中国医院用药评价与分析》 2024年第7期774-777,782,共5页
目的:探讨表皮生长因子受体(EGFR)基因少见突变P733L对第1代和第3代EGFR酪氨酸激酶抑制剂(EGFR-TKI)的敏感性。方法:通过四唑盐比色法和平板克隆实验分析EGFR L858R和P733L肺癌细胞对第1代和第3代EGFR-TKI的敏感性;通过Transwell实验分... 目的:探讨表皮生长因子受体(EGFR)基因少见突变P733L对第1代和第3代EGFR酪氨酸激酶抑制剂(EGFR-TKI)的敏感性。方法:通过四唑盐比色法和平板克隆实验分析EGFR L858R和P733L肺癌细胞对第1代和第3代EGFR-TKI的敏感性;通过Transwell实验分析第1代和第3代EGFR-TKI对EGFR L858R和P733L肺癌细胞迁移的抑制作用;通过检测凋亡蛋白分析第1代和第3代EGFR-TKI促进EGFR L858R和P733L肺癌细胞凋亡的作用。结果:第1代和第3代EGFR-TKI对EGFR L858R和P733L细胞的增殖、克隆形成和细胞迁移都有抑制作用。与EGFR野生型肺癌细胞相比,第1代和第3代EGFR-TKI处理后,EGFR L858R和P733L细胞的EGFR激酶活性受到抑制,细胞凋亡明显增加。结论:EGFR P733L突变细胞对第1代和第3代EGFR-TKI的敏感性与EGFR L858R突变细胞的敏感性相似,本研究为EGFR基因少见突变从EGFR-TKI治疗中获益提供了实验证据。 展开更多
关键词 非小细胞肺癌 表皮生长因子受体酪氨酸激酶抑制剂 EGFR少见突变 EGFR p733l 药物敏感性
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基于L型轮辐结构膜片的窄频光纤F-P声波传感器研究
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作者 王巧云 闻妲 +2 位作者 王纪龙 严重越 朱子恒 《仪器仪表学报》 EI CAS CSCD 北大核心 2024年第5期110-117,共8页
光纤声传感器被广泛应用在工业、医疗等领域。为了提高光纤F-P声传感器的性能,本文提出了一种L型轮辐结构的F-P传感膜片。膜片的厚度为15μm、梁宽度为0.5 mm、中心膜片的半径为1 mm。膜片由激光加工技术在304不锈钢上刻蚀而成。实验对1... 光纤声传感器被广泛应用在工业、医疗等领域。为了提高光纤F-P声传感器的性能,本文提出了一种L型轮辐结构的F-P传感膜片。膜片的厚度为15μm、梁宽度为0.5 mm、中心膜片的半径为1 mm。膜片由激光加工技术在304不锈钢上刻蚀而成。实验对1000 Hz下的传感器灵敏度进行研究,将传感器应用于光声池共振频率为1600 Hz的光声光谱气体检测系统中,并实现对50~100×10^(-6)的乙炔(C_(2)H_(2))气体浓度测量。实验结果表明,该传感器在1000 Hz下的声压灵敏度为25.4 nm/Pa,传感器可实现的最小可探测声压(MDP)为38.2μPa/Hz^(1/2)@1 kHz,声压信噪比为76.8 dB。实验所得到的光声光谱二次谐波信号的峰值与乙炔浓度呈现良好的线性关系,乙炔浓度的响应度为1.8 pm/10^(-6)。该传感器在光声光谱等单频声信号检测领域具有广泛的应用前景。 展开更多
关键词 光纤声传感器 F-p干涉 l型轮辐结构 光声光谱
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P和L波段的典型地物雷达散射系数的研究
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作者 刘志坤 江凯 +3 位作者 乔兴旺 谈璐璐 张佳佳 刘永涛 《航天返回与遥感》 CSCD 北大核心 2024年第4期91-98,共8页
能够反映地物散射特性的雷达散射系数应用前景广泛,具有重要的学术价值。国内外对于L波段同极化和交叉极化雷达散射系数的差值的相关研究较少,且暂无公开的P波段典型地物的雷达散射系数数据,为了弥补这一现状,文章结合国内外实测数据分... 能够反映地物散射特性的雷达散射系数应用前景广泛,具有重要的学术价值。国内外对于L波段同极化和交叉极化雷达散射系数的差值的相关研究较少,且暂无公开的P波段典型地物的雷达散射系数数据,为了弥补这一现状,文章结合国内外实测数据分析了P波段和L波段雷达散射系数和入射角的变化关系,并对L波段和P波段典型地物的雷达散射系数进行了比较。结果表明:L波段HH极化和HV极化雷达散射系数的差值随着入射角的增大而减小,在40°入射角时,典型地物的差值在10~13 dB;P波段典型地物雷达散射系数随着入射角的增加而减小,且比L波段小1~2 dB;P波段HH极化和HV极化雷达散射系数差值随着入射角的增大而减小。文章的研究为P、L波段雷达的遥感应用积累了数据,为极化SAR反演目标信息提供帮助和借鉴。 展开更多
关键词 交叉极化 同极化 后向散射系数 l波段 p波段
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CircRTN4调节miR-224-5p/MYT1L轴对胶质母细胞瘤细胞恶性生物学行为的影响 被引量:1
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作者 刘应刚 李维民 +3 位作者 龙勇 向城卫 张施远 陈星宇 《河北医学》 2024年第1期15-22,共8页
目的:探讨环状RNA(CircRNA)RTN4调节微小RNA(miR)-224-5p/髓磷脂转录因子1样(MYT1L)轴对胶质母细胞瘤(GM)细胞恶性生物学行为的影响。方法:以对数生长期的U251细胞进行设置分组:空白组、阴性对照(sh NC)组、沉默circRTN4 shRNA(sh circR... 目的:探讨环状RNA(CircRNA)RTN4调节微小RNA(miR)-224-5p/髓磷脂转录因子1样(MYT1L)轴对胶质母细胞瘤(GM)细胞恶性生物学行为的影响。方法:以对数生长期的U251细胞进行设置分组:空白组、阴性对照(sh NC)组、沉默circRTN4 shRNA(sh circRTN4)组、sh circRTN4+抑制剂对照(inhibitor NC)组、sh circRTN4+miR-224-5p抑制剂(miR-224-5p inhibitor)组。Transwell实验、流式细胞术、CCK-8、qRT-PCR、Western blot以及双荧光素酶分别检测细胞迁移与侵袭、凋亡、增殖、CircRTN4、miR-224-5p、MYT1L mRNA表达、增殖蛋白(ki-67)、凋亡蛋白(cleaved Caspase-3)、MYT1L蛋白表达以及miR-224-5p分别与CircRTN4、MYT1L靶向关系验证;qRT-PCR检测GM细胞系U118、U87、U251和LN229细胞及正常人星形胶质细胞系NHA细胞中CircRTN4、miR-224-5p、MYT1L mRNA表达水平。结果:U118、U87、U251和LN229细胞中CircRTN4、MYT1L mRNA表达较NHA细胞显著增加,miR-224-5p表达显著下降(P<0.05);miR-224-5p分别与CircRTN4、MYT1L的有靶向关系。与空白组、sh NC组相比,sh circRTN4组迁移、侵袭数、24h、48h A450值、ki-67、CircRTN4、MYT1L mRNA及蛋白表达显著降低,凋亡率、cleaved Caspase-3表达显著增加(P<0.05);与sh circRTN4+inhibitor NC组相比,sh circRTN4+miR-224-5p inhibitor组迁移、侵袭数、24h、48h A450值、ki-67、MYT1L mRNA及蛋白表达显著增加,凋亡率、cleaved Caspase-3表达显著下降(P<0.05),CircRTN4表达无统计学差异(P>0.05),体内实验证明干扰CircRTN4可显著抑制移植瘤裸鼠肿瘤质量(P<0.05)。结论:沉默CircRTN4调节miR-224-5p/MYT1L轴抑制GM细胞恶性生物学行为。 展开更多
关键词 胶质母细胞瘤 环状RTN4 miR-224-5p/MYT1l 恶性生物学行为
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P/L波段大带宽轻质柔性超材料吸波体
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作者 李士贤 吴微微 +2 位作者 崔开博 王福兴 许逸轩 《电讯技术》 北大核心 2024年第10期1582-1589,共8页
为了适应现代武器设备在低频端的应用和对于吸波性能的要求,基于电磁超材料理论,利用电磁谐振特性设计了一种在P/L波段工作的大带宽轻质柔性吸波体。当电磁波入射到该新型吸波体,根据电磁感应作用机理,会在吸波体表面产生感应电流,通过... 为了适应现代武器设备在低频端的应用和对于吸波性能的要求,基于电磁超材料理论,利用电磁谐振特性设计了一种在P/L波段工作的大带宽轻质柔性吸波体。当电磁波入射到该新型吸波体,根据电磁感应作用机理,会在吸波体表面产生感应电流,通过装载集总电阻的方式,可将入射电磁波的能量转化为热能,从而实现对于电磁波的有效吸收。对于吸波体单元结构形状和尺寸的设计使得该吸波体具有两处谐振频点,并通过多谐振频率的耦合进一步展宽吸波带宽。仿真和实测结果验证了吸波体的优良性能。其工作频段为382~1419.4 MHz,相对带宽为140.9%,吸波层厚度仅为0.2 mm,在保证大带宽的同时具有重量轻、可共形的优点,在转台曲面吸波、雷达隐身等领域具有广阔的应用前景。 展开更多
关键词 电磁超材料 p/l波段 柔性吸波体
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Arsenic uptake and transport of Pteris vittata L.as influenced by phosphate and inorganic arsenic species under sand culture 被引量:9
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作者 HUANG Ze-chun AN Zhi-zhuang CHEN Tong-bin LEI Mei XIAO Xi-yuan LIAO Xiao-yong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第6期714-718,共5页
In order to understand the similarity or difference of inorganic As species uptake and transport related to phosphorus in Ashyperaccumulator, uptake and transport of arsenate (As(V)) and arsenite (As(Ⅲ)) were... In order to understand the similarity or difference of inorganic As species uptake and transport related to phosphorus in Ashyperaccumulator, uptake and transport of arsenate (As(V)) and arsenite (As(Ⅲ)) were studied using Pteris vittata L. under sand culture. Higher concentrations of phosphate were found to inhibit accumulation of arsenate and arsenite in the fronds of P. vittata. The reduction in As accumulation was greater in old fronds than in young fronds, and relatively weak in root and rhizome. Moderate increases, from 0.05 to 0.3 mmol/L, in phosphate reduced uptake of As(Ⅲ) more than As(Ⅴ), while the reverse was observed at high concentrations of phosphate (≥1.0 mmol/L). Phosphate apparently reduced As transport and the proportion of As accumulated in fronds of P. vittata when As was supplied as As(Ⅴ). It may in part be due to competition between phosphorus and As(Ⅴ) during transport. In contrast, phosphate had a much smaller effect on As transport when the As was supplied as As(Ⅲ). Therefore, the results from present experiments indicates that a higher concentration of phosphate suppressed As accumulation and transport in P. vittata, especially in the fronds, when exposed to As(Ⅴ), but the suppression of phosphate to As transport may be insignificant when P. vittata exposed to As(Ⅲ) under sand culture conditions. The finding will help to understand the interaction of P and As during their uptake process in P. vittata. 展开更多
关键词 ARSENATE ARSENITE As species pteris vittata l. pHOSpHATE transport UpTAKE
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Potential of Pteris vittata L. for phytoremediation of sites co-contaminated with cadmium and arsenic: The tolerance and accumulation 被引量:11
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作者 XIAO Xiyuan CHEN Tongbin AN Zhizhuang LEI Mei HUANG Zechun LIAO Xiaoyong LIU Yingru 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第1期62-67,共6页
Field investigation and greenhouse experiments were conducted to study the tolerance of Pteris vittata L. (Chinese brake) to cadmium (Cd) and its feasibility for remediating sites co-contaminated with Cd and arsen... Field investigation and greenhouse experiments were conducted to study the tolerance of Pteris vittata L. (Chinese brake) to cadmium (Cd) and its feasibility for remediating sites co-contaminated with Cd and arsenic (As). The results showed that P. vittata could survive in pot soils spiked with 80 mg/kg of Cd and tolerated as great as 301 mg/kg of total Cd and 26.8 mg/kg of diethyltriaminepenta acetic acid (DTPA)-extractable Cd under field conditions. The highest concentration of Cd in fronds was 186 mg/kg under a total soil concentration of 920 mg As/kg and 98.6 mg Cd/kg in the field, whereas just 2.6 mg/kg under greenhouse conditions. Ecotypes of P. vittata were differentiated in tolerance and accumulation of Cd, and some of them could not only tolerate high concentrations of soil Cd, but also accumulated high concentrations of Cd in their fronds. Arsenic uptake and transportation by P. vittata was not inhibited at lower levels (〈20 mg/kg) of Cd addition. Compared to the treatment without addition of Cd, the frond As concentration was increased by 103.8% at 20 mg Cd/kg, with the highest level of 6434 mg/kg. The results suggested that the Cd-tolerant ecotype of P. vittata extracted effectively As and Cd from the site co-contaminated with Cd and As, and might be used to remediate and revegetate this type of site. 展开更多
关键词 arsenic (As) cadmium (Cd) Chinese brake pteris vittata l.) HYpERACCUMUlATOR pHYTOREMEDIATION TOlERANCE uptake
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MyD88L265P及CD79B基因突变对原发性中枢神经系统淋巴瘤预后的影响
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作者 蒋皓云 金祺祺 +3 位作者 张丽田 李翠翠 岳宁宁 吴重阳 《解放军医学杂志》 CAS CSCD 北大核心 2024年第1期57-63,共7页
目的探究MyD88L265P及CD79B基因突变对原发性中枢神经系统淋巴瘤(PCNSL)患者预后的影响。方法收集2018年8月-2020年11月于兰州大学第二医院经开颅手术或立体定位活检术确诊的18例免疫功能正常(无HIV感染及免疫抑制药服用病史)的PCNSL患... 目的探究MyD88L265P及CD79B基因突变对原发性中枢神经系统淋巴瘤(PCNSL)患者预后的影响。方法收集2018年8月-2020年11月于兰州大学第二医院经开颅手术或立体定位活检术确诊的18例免疫功能正常(无HIV感染及免疫抑制药服用病史)的PCNSL患者临床资料进行回顾性分析。分别采用实时荧光定量PCR和一代基因测序技术检测18例PCNSL患者肿瘤组织中MyD88L265P和CD79B基因突变情况。针对可能与PCNSL首次无疾病进展生存期(PFS)和总生存期相关的指标行单因素分析,并采用Cox回归进行多因素分析。结果18例PCNSL肿瘤组织MyD88L265P突变率为38.9%,CD79B突变率为33.3%,MyD88L265P/CD79B共突变率为27.8%。单因素分析结果显示,病灶多发、病灶深部受累、肿瘤组织CD79B突变患者的PFS时间更短(P<0.05);多因素分析结果显示,病灶深部受累(HR=0.135,95%CI 0.023~0.799,P<0.05)、肿瘤组织CD79B突变(HR=0.149,95%CI 0.028~0.800,P<0.05)是PCNSL患者预后不良的独立危险因素。结论本组PCNSL患者肿瘤组织MyD88L265P、CD79B突变频率较高,这两种基因突变尤其是CD79B突变可能与PCNSL不良预后相关。 展开更多
关键词 原发性中枢神经系统淋巴瘤 MyD88l265p突变 CD79B突变 预后
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基于P-L双重特征提取的PEMFC系统故障诊断方法
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作者 贺飞 张雪霞 陈维荣 《太阳能学报》 EI CAS CSCD 北大核心 2024年第1期492-499,共8页
针对质子交换膜燃料电池系统故障诊断问题,提出基于P-L双重特征提取的故障诊断方法。使用P-L双重特征提取对预处理后的样本数据进行特征提取,通过冗余变量剔除与二次特征提取,最大程度保留分类特征并有效降低样本数据维度。利用二叉树... 针对质子交换膜燃料电池系统故障诊断问题,提出基于P-L双重特征提取的故障诊断方法。使用P-L双重特征提取对预处理后的样本数据进行特征提取,通过冗余变量剔除与二次特征提取,最大程度保留分类特征并有效降低样本数据维度。利用二叉树多类支持向量机与极限学习机对二维故障特征向量进行分类实现故障诊断。通过实例验证,对比线性判别分析的特征提取效果,P-L双重特征提取可使相同分类器测试集诊断准确率提高21.19%,诊断准确率达99.27%,实现了PEMFC系统膜干、氢气供应故障的精准快速诊断。 展开更多
关键词 质子交换膜燃料电池 故障检测 数据挖掘 p-l双重特征提取 支持向量机 极限学习机
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基于改进L-P法的块系岩体摆型波与准共振机理分析
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作者 徐天涵 崔海涛 +3 位作者 邓勇 邢灏喆 李超 纪玉国 《陆军工程大学学报》 2024年第5期1-10,共10页
块系岩体中摆型波具有非线性特征,导致难以解释其频谱特征及准共振现象机理。针对此问题,建立了考虑三次项的摆型波非线性振动模型,利用改进的L-P法与振型叠加法,求得多自由度强非线性振动的近似解析解,一定程度上解释了试验观测到块系... 块系岩体中摆型波具有非线性特征,导致难以解释其频谱特征及准共振现象机理。针对此问题,建立了考虑三次项的摆型波非线性振动模型,利用改进的L-P法与振型叠加法,求得多自由度强非线性振动的近似解析解,一定程度上解释了试验观测到块系岩体摆型波的非线性现象机理。结果表明,块体系统振动频率可表示为输入能量的高次多项式,随能量增大振动频率呈非单调变化;各谐振频率之间的比例与系统构造有关,近似满足√2的整数倍比例关系。通过建立摆型波的层次构造模型,得出准共振是摆型波在不同尺度块体之间跃迁的标志。 展开更多
关键词 摆型波 强非线性 改进l-p 块系岩体 准共振
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一类漂移系数分段连续的随机微分方程驯服Euler方法的L^(p)收敛率
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作者 胡慧敏 甘四清 《数学理论与应用》 2024年第2期1-19,共19页
本文研究一类漂移系数分段连续的标量随机微分方程的驯服Euler方法的L^(p)收敛率.更确切地说,本文在漂移系数是分段连续的并且呈多项式增长,扩散系数是Lipschitz连续的并且在漂移系数的间断点处不为0的假设下,证明方程具有唯一的强解,... 本文研究一类漂移系数分段连续的标量随机微分方程的驯服Euler方法的L^(p)收敛率.更确切地说,本文在漂移系数是分段连续的并且呈多项式增长,扩散系数是Lipschitz连续的并且在漂移系数的间断点处不为0的假设下,证明方程具有唯一的强解,并且对于任意的p∈[1,∞),驯服Euler方法的L^(p)收敛阶都可以达到1/2.此外,本文还提供一个数值算例来验证理论结果. 展开更多
关键词 随机微分方程 漂移系数 驯服Euler方法 l^(p)收敛率
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喉癌肿瘤组织NOC2L、p53表达及其临床价值研究
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作者 凡丹丹 高芳芳 +1 位作者 邹婧 李鹏程 《疑难病杂志》 CAS 2024年第10期1177-1181,共5页
目的检测喉癌肿瘤组织中NOC2L、p53 mRNA表达并研究其临床价值。方法选取2020年1月—2022年1月武汉大学附属同仁医院诊治的喉癌患者103例(喉癌组)和喉良性疾病患者57例(对照组)。采用实时荧光定量聚合酶链反应检测组织NOC2L、p53 mRNA... 目的检测喉癌肿瘤组织中NOC2L、p53 mRNA表达并研究其临床价值。方法选取2020年1月—2022年1月武汉大学附属同仁医院诊治的喉癌患者103例(喉癌组)和喉良性疾病患者57例(对照组)。采用实时荧光定量聚合酶链反应检测组织NOC2L、p53 mRNA表达。比较喉癌不同临床病理特征中肿瘤组织NOC2L、p53 mRNA表达差异。受试者工作特征(ROC)曲线分析肿瘤组织NOC2L、p53表达预测喉癌患者预后不良的价值;多因素Cox回归模型分析喉癌预后不良的危险因素;Kaplan-Meier模型分析NOC2L、p53表达对喉癌生存期的影响。结果与对照组比较,喉癌组患者NOC2L表达升高,p53表达降低(t/P=19.307/<0.001、13.726/<0.001)。组织学分级3级、原发肿瘤大小≥3 cm、转移淋巴结数N2~3、远处转移M1及TNM分期Ⅲ~Ⅳ期喉癌患者肿瘤组织NOC2L mRNA表达高于组织学分级1~2级、原发肿瘤大小<3 cm、转移淋巴结数N0~1、远处转移M0及TNM分期Ⅰ~Ⅱ期患者(t/P=3.681/0.001、4.167/<0.001、2.554/0.012、4.005/<0.001、3.228/<0.001),p53 mRNA表达低于组织学分级1~2级、原发肿瘤大小<3 cm、转移淋巴结数N0~1、远处转移M0及TNM分期Ⅰ~Ⅱ期患者(t/P=4.162/<0.001、4.789/<0.001、4.053/<0.001、3.492/<0.001、3.724/<0.001);NOC2L、p53及二者联合预测喉癌预后不良的AUC分别为0.756、0.712、0.917,二者联合优于各自单独预测效能(Z=7.238、8.102,P<0.001)。NOC2L≥0.73、p53≤0.65、组织学分级3级、原发肿瘤大小≥3 cm、转移淋巴结数N2~3、远处转移M1及TNM分期Ⅲ~Ⅳ期为喉癌预后不良的独立危险因素[HR(95%CI)=5.328(1.455~9.201)、4.200(1.279~7.122)、1.992(1.127~2.857)、2.164(1.099~3.299)、2.228(1.304~3.152)、2.406(1.131~3.681)、2.514(1.278~3.762)];NOC2L≥0.81且p53≤0.54喉癌患者中位生存期显著低于NOC2L<0.81或p53>0.54患者中位生存期(Log Rankχ^(2)=9.033,P<0.001)。结论喉癌患者NOC2L及p53表达与病情严重程度及生存期显著相关,可为喉癌病情及预后评估提供客观证据,NOC2L及p53联合检测可显著提高其临床价值。 展开更多
关键词 喉癌 NOC2l p53 肿瘤组织 临床价值
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MicroRNA-329-3p inhibits the Wnt/β-catenin pathway and proliferation of osteosarcoma cells by targeting transcription factor 7-like 1
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作者 Hur SUN MASANORI KAWANO +4 位作者 TATSUYA IWASAKI ICHRO ITONAGA YUTA KUBOTA HROSHI TSUMURA KAZUHRO TANAKA 《Oncology Research》 SCIE 2024年第3期463-476,共14页
An important factor in the emergence and progre sion of osteosarcoma(OS)is the dysregulated expression of microRNAs(miRNAs).Transcription factor 7-like 1(TCF7LI),a member of the T cell factor/lymphoid enhancer factor(... An important factor in the emergence and progre sion of osteosarcoma(OS)is the dysregulated expression of microRNAs(miRNAs).Transcription factor 7-like 1(TCF7LI),a member of the T cell factor/lymphoid enhancer factor(TCF/LEF)transcription factor family,interacts with the Wnt signaling pathway regulator β-catenin and acts as a DNA-specific binding protein.This study sought to elucidate the impact of the interaction between miR 3293p and TCF7L1 on.the growth and apoptosis of OS and analyze the regulatory expression relationship between miRNA and mRNA in osteosarcoma cells using a variety of approaches.MiR329-3p was significantly downregulated,while TCF7L1 was considerably up-regulated in all examined OS cell lines.Additionally,a clinical comparison study was performed using the TCGA database.Subsequently,the regulatory relationship between miR-329-3p and TCF7L1 on the proliferation and apoptosis of OS cells was verified through in vitro and in vivo experiments.When miR 329-3p was transfected into the OS cell line,the expression of TCF7L1 decreased,the proliferation of OS cells was inhibited,the cytoskeleton disintegrated,and the nucleus condensed to fom apoptotic bodies.The expression of proteins that indicate apoptosis increased simultaneously.The cell cycle was arrested in the G0/G1 phase,and the G1/S transition was blocked.The introduction of miR 3293p also inhibited downstream Cyclin D1 of the Wnt pathway.Xenograf experiments indicated that the overexpression of miR-329-3p signi ficanly inhibited the growth of OS xenografts in nude mice,and the expression of TCF7L1 and C-Myc in tumor tssues decreased.MiR 329-3p was significantly reduced in OS cells and played a suppressive role in tumorigenesis and proliferation by targeting TCF7L1 both in vitro and in vivo.Osteosarcoma cell cycle arrest and pathway inhibition were observed upon the regulation of TCF7LI by miR 3293p.Summarizing these results,it can be inferred that miR.3293p exerts anticancer efects in osteosarcoma by inhibiting TCF7L1. 展开更多
关键词 MiR-329-3p TCF7l1 Wnt/β-catenin pathway OSTEOSARCOMA pROlIFERATION
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Hardy-Littlewood截断极大算子的L^(p)范数的连续性
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作者 武嘉 魏明权 燕敦验 《中国科学院大学学报(中英文)》 CSCD 北大核心 2024年第1期28-34,共7页
研究截断极大算子M^(b)_(a)的L_(p)(R^(n))→L_(p)(R^(n))范数的连续性。首先,分别给出‖M^(b)_(a)‖L_(p)(R^(n))→L_(p)(R^(n))关于参数θ=b/a的左右连续性,然后证明‖M^(b)_(a)‖L_(p)(R^(n))→L_(p)(R^(n))在无穷远处的连续性。
关键词 截断极大算子 连续性 l_(p)(R^(n))→l_(p)(R^(n))范数
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miR-212-3p靶向调控NAP1L1抑制胶质瘤细胞增殖、迁移和上皮-间充质转化
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作者 郭小兵 李晓文 +2 位作者 李恒希 曹艳 李坪 《昆明医科大学学报》 CAS 2024年第11期22-30,共9页
目的探究miR-212-3p在胶质瘤细胞增殖、侵袭和上皮-间充质转化(EMT)中的分子机制。方法RT-qPCR用于衡量胶质瘤细胞中miR-212-3p和NAP1L1表达,构建NC mimic、miR-212-3p mimic、oeNC和oe-NAP1L1转染至细胞中,利用CCK-8、Transwell和伤口... 目的探究miR-212-3p在胶质瘤细胞增殖、侵袭和上皮-间充质转化(EMT)中的分子机制。方法RT-qPCR用于衡量胶质瘤细胞中miR-212-3p和NAP1L1表达,构建NC mimic、miR-212-3p mimic、oeNC和oe-NAP1L1转染至细胞中,利用CCK-8、Transwell和伤口实验评估细胞生物学行为。通过Western blot分析EMT相关标志物的蛋白表达。miR-212-3p与NAP1L1的关系通过双荧光素酶报告基因和AgO2-RIP实验进行证实。结果miR-212-3p的表达水平在胶质瘤细胞中显著下调(P<0.0001),过表达miR-212-3p可以显著降低胶质瘤细胞增殖(P<0.0001)、侵袭(P=0.0011)和迁移能力(P<0.0001),并且抑制了EMT标志物N-钙黏蛋白(N-cadherin)(P=0.000861)和波形蛋白(Vimentin)(P=0.007430)的表达,而上调了E-钙黏蛋白(Ecadherin)(P<0.0001)的表达。miR-212-3p靶向负调控NAP1L1的表达。过表达NAP1L1逆转了miR-212-3p对胶质瘤细胞增殖(P<0.0001)、迁移(P<0.0001)和EMT(P<0.0001)的抑制作用。结论miR-212-3p通过靶向负调节NAP1L1的表达抑制胶质瘤细胞增殖、迁移和EMT。 展开更多
关键词 胶质瘤 miR-212-3p NAp1l1 上皮-间充质转化 细胞增殖
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阴道镜检查联合HPV L1壳蛋白、p16蛋白检测筛查宫颈上皮内瘤变效果
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作者 王颖 陈飞 +2 位作者 苏展 贺竞 苏晓兰 《中国计划生育学杂志》 2024年第10期2415-2418,2464,共5页
目的:探讨宫颈病变筛查中阴道镜检查、人乳头瘤病毒L1(HPV L1)壳蛋白检测、多肿瘤抑制基因(MTS1,p16蛋白)检测和联合诊断在宫颈上皮内瘤变(CIN)的临床应用效果。方法:收集2022年6月-2023年6月本院妇科门诊因疑存宫颈病变进行宫颈癌筛查... 目的:探讨宫颈病变筛查中阴道镜检查、人乳头瘤病毒L1(HPV L1)壳蛋白检测、多肿瘤抑制基因(MTS1,p16蛋白)检测和联合诊断在宫颈上皮内瘤变(CIN)的临床应用效果。方法:收集2022年6月-2023年6月本院妇科门诊因疑存宫颈病变进行宫颈癌筛查的女性201例,均行HPV L1壳蛋白、p16蛋白检测和阴道镜检查,以阴道镜下宫颈组织活检病理结果为诊断依据,对HPV L1壳蛋白、p16蛋白检测、阴道镜检查及3项联合诊断的效果进行分析。结果:宫颈病理诊断无病变121例,病变80例(CIN1级54例、CIN2级25例、CIN3级1例)。阴道镜CIN检出率为53.7%,灵敏度81.3%,特异度64.5%,准确度为71.1%;HPV L1壳蛋白检测CIN检出率为55.2%,灵敏度73.8%,特异度为57.0%,精确度为63.7%。p16蛋白检测CIN检出率为53.7%,灵敏度83.8%,特异度66.1%,精确度73.1%。3项联合检测CIN检出率为64.2%,灵敏度97.5%,特异度57.9%,精确度74.6%。筛查灵敏度阴道镜、HPV L1壳蛋白、p16蛋白检测无差异(χ^(2)=2.667,P>0.05),但3项联合诊断的灵敏度高于各单独指标检测(χ^(2)=11.123、18.331、8.901,P<0.05),特异度3项联合诊断与单独指标无差异(χ^(2)=3.233,P>0.05)。结论:阴道镜检查联合HPV L1壳蛋白,p16蛋白检测筛查CIN的灵敏度可显著提高,可为临床提供有价值的诊断证据。 展开更多
关键词 宫颈上皮内瘤变 阴道镜 HpV l1壳蛋白 p16蛋白 灵敏度
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Th17细胞功能相关基因OX40L筛选及其与miR-146a-3p靶向关系验证、对Th17细胞迁移调控作用机制探讨
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作者 黄韵 李春美 李作孝 《山东医药》 CAS 2024年第36期29-35,39,共8页
目的筛选Th17细胞功能相关基因OX40L,验证其与微小核糖核酸146a-3p(miR-146a-3p)的靶向关系,并探讨其对Th17细胞迁移的调控作用机制。方法①通过在GEO数据集中搜索multiple sclerosis,筛选出GSE57098基因数据集,R语言获取CD4+T细胞和Th1... 目的筛选Th17细胞功能相关基因OX40L,验证其与微小核糖核酸146a-3p(miR-146a-3p)的靶向关系,并探讨其对Th17细胞迁移的调控作用机制。方法①通过在GEO数据集中搜索multiple sclerosis,筛选出GSE57098基因数据集,R语言获取CD4+T细胞和Th17细胞的差异基因,DAVID 6.8在线分析软件获取GO分析及KEGG分析,STRING在线分析网站获取蛋白互作关系,Cytoscape软件获取Th17细胞功能相关的Hub蛋白,选取关键蛋白OX40L,并用qPCR进行验证。②使用Starbase预测miR-146a-3p与OX40L存在结合位点,双荧光素酶报告实验验证miR-146a-3p与OX40L靶向关系。③体外培养生长良好的Th17细胞,给予miR-146a-3p模拟物和抑制剂及其对照处理,qRT-PCR检测Th17细胞miR-146a-3p mRNA,CCK8增殖实验检测各组Th17细胞增殖情况,Transwell小室侵袭实验检测各组Th17细胞迁移情况,流式细胞术检测各组Th17细胞凋亡比例;qRT-PCR法和Western blot法检测各组OX40L mRNA和蛋白,ELISA法检测各组Th17细胞TNF-α。结果①GSE57098数据集中Th17细胞和CD4+T细胞有差异基因2130个,其中表达上调1515个,表达下调615个,OX40L在表达上调的蛋白中排名靠前。OX40L在KEGG分析中参与Cytokine-cytokinereceptorinteraction途径。②miR-146a-3p与OX40LmRNA3'UTR呈靶向结合关系,miR-146a-3p可抑制OX40L基因的转录表达。③与对照组比较,miR-146a-3pmimic组Th17细胞TLR4和p-NFκBp65蛋白表达降低,分泌TNF-α能力降低,细胞迁移能力降低,P均<0.05。结论OX40L在Th17细胞基因表达谱发生明显变化,其表达上调是造成多发性硬化发病的机制之一;miR-146a-3p通过靶向调节OX40L的表达,进一步抑制TNF-α途径中NF-κB p65的翻译水平,降低Th17细胞的迁移。 展开更多
关键词 多发性硬化 OX40l基因 TH17细胞 微小核糖核酸146a-3p TNF-α途径
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