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17~45岁肥胖门诊患者的6分钟步行试验距离参考方程研究
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作者 张家鸣 王欣宇 +1 位作者 王道荣 孙晓芳 《中国全科医学》 CAS 北大核心 2025年第3期330-334,345,共6页
背景 目前6分钟步行试验(6MWT)已经被广泛用于评估肥胖人群的运动能力,并为制订干预措施提供了参考依据。国外已有研究提出了其他人群的6MWT距离参考方程,但中国17~45岁且BMI≥30 kg/m^(2)肥胖受试者的6MWT距离参考方程研究较少。目的 ... 背景 目前6分钟步行试验(6MWT)已经被广泛用于评估肥胖人群的运动能力,并为制订干预措施提供了参考依据。国外已有研究提出了其他人群的6MWT距离参考方程,但中国17~45岁且BMI≥30 kg/m^(2)肥胖受试者的6MWT距离参考方程研究较少。目的 为17~45岁门诊肥胖受试者制订6MWT距离参考方程,并评估其影响因素。方法 根据美国胸科学会指南,前瞻性选取2022年6月—2023年9月于江苏省苏北人民医院内分泌科肥胖门诊部就诊的143名年龄17~45岁且BMI≥30 kg/m^(2)的成年人(71名男性和72名女性),进行人体测量和6MWT。采用逐步多元回归模型建立6MWT距离参考方程,将新建立的6MWT距离参考方程与现有的预测方程进行比较。结果 143名受试者的平均6MWT距离为(506.1±49.8)m,其中男性平均6MWT距离为(515.7±50.1)m,大于女性的平均6MWT距离(496.6±47.9)m(P<0.05)。在年龄段17~23岁、24~30岁、31~37岁以及38~45岁中,男性与女性6MWT距离比较,差异均有统计学意义(P<0.05)。男性受试者的体质量、BMI、最大心率(HR_(max))、心率差(ΔHR)、腰围、舒张压差(ΔDBP)、Borg量表评分差(ΔBorg)与6MWT距离相关(P<0.05),女性受试者的体质量、BMI、腰围与6MWT距离相关(P<0.05)。以步进的方法将潜在的影响因素纳入多元线性回归方程中,最终建立6MWT距离参考公式:男性y=494.463+1.414×ΔHR-3.903×BMI+0.874×HR_(max),R^(2)=0.429,女性y=670.448+0.299×ΔHR-4.342×BMI-0.195×HR_(max),R^(2)=0.312。结论 17~45岁门诊肥胖受试者中,男性的平均6MWT距离长于女性,且在不同年龄段均有显著差异。男性的体质量、BMI、HR_(max)、ΔHR、腰围、ΔDBP、ΔBorg与6MWT距离相关,女性的体质量、BMI、腰围、ΔSBP与6MWT距离相关。通过多元线性回归分析,为男性和女性分别建立了预测6MWT距离的参考方程,这些公式可能为评估个体的体能水平提供有价值的参考。 展开更多
关键词 肥胖症 步行试验 距离方程 17~45岁 6分钟步行试验 影响因素分析
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金属二聚体和氮共掺杂石墨烯(Gra)M_(2)N_(6)-Gra(M=Cr-Cu)的NO_(2)吸附特性理论研究
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作者 张展博 余娇 +5 位作者 魏亚茹 张轩 靳鑫 张子音 杨保成 张雷雷 《原子与分子物理学报》 CAS 北大核心 2025年第5期35-42,共8页
NO_(2)是空气污染物的主要成分之一,设计和开发高效的气敏传感器对NO_(2)进行检测具有重要意义.本工作利用基于密度泛函理论(DFT)的第一性原理计算方法对不同过渡金属原子形成的金属二聚体和氮共掺杂石墨烯(Gra)M_(2)N_(6)-Gra(M=Cr-Cu)... NO_(2)是空气污染物的主要成分之一,设计和开发高效的气敏传感器对NO_(2)进行检测具有重要意义.本工作利用基于密度泛函理论(DFT)的第一性原理计算方法对不同过渡金属原子形成的金属二聚体和氮共掺杂石墨烯(Gra)M_(2)N_(6)-Gra(M=Cr-Cu)的NO_(2)吸附特性进行了研究.结果表明,NO_(2)分子与M_(2)N_(6)-Gra之间均存在明显的化学吸附作用.其中,Ni_(2)N_(6)-Gra和Cu_(2)N_(6)-Gra体系具备较为适中的恢复时间(分别约为5秒和14分钟),这意味着这两个体系是开发新型NO_(2)气敏材料的潜在候选者.其它体系(M_(2)N_(6)-Gra,M=Cr-Co)强的吸附作用导致恢复时间过长,从而使得它们不适合作为NO_(2)气敏材料.这一研究不仅有望为设计和开发性能优异的新型NO_(2)气敏材料提供有益理论指导,还将有益于人们深入认识M_(2)N_(6)-Gra材料的NO_(2)电催化合成NO或NH 3性能. 展开更多
关键词 M_(2)N_(6)-Gra NO_(2)吸附 密度泛函理论
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m^(6)A修饰在病毒感染宿主细胞中的调节作用
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作者 夏月平 黄芬 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2024年第10期1362-1373,共12页
N^(6)-甲基腺苷(N^(6)-methyladenosine,m^(6)A)是指RNA分子腺嘌呤第6位氮原子上发生的甲基化修饰,是信使RNA(mRNA)和非编码RNA(ncRNA)中最常见的转录后修饰。m^(6)A修饰在RNA循环的所有阶段,包括RNA稳定、剪接、核输出、折叠、翻译和... N^(6)-甲基腺苷(N^(6)-methyladenosine,m^(6)A)是指RNA分子腺嘌呤第6位氮原子上发生的甲基化修饰,是信使RNA(mRNA)和非编码RNA(ncRNA)中最常见的转录后修饰。m^(6)A修饰在RNA循环的所有阶段,包括RNA稳定、剪接、核输出、折叠、翻译和降解等过程中发挥重要作用,这一过程需甲基转移酶(writers)、去甲基酶(erasers)和m^(6)A阅读蛋白(readers)的参与。随着RNA高通量测序技术的不断发展,m^(6)A修饰参与病毒与宿主互作中的研究不断涌现。研究表明m^(6)A修饰发生在多种RNA病毒中,影响病毒感染、复制及子代病毒粒子的生成。病毒也可通过改变宿主细胞转录物组的m^(6)A修饰影响病毒的感染性或宿主对病毒的抵抗性。本文对呼吸道病毒、反转录病毒、疱疹病毒等感染宿主细胞造成的m^(6)A修饰进行概述,并针对m^(6)A修饰对病毒的复制及对宿主免疫反应的调节作用进行综述,为了解病毒与宿主互作机制研究及抗病毒药物筛选供理论基础。 展开更多
关键词 N^(6)-methyladenosine(m^(6)A) m^(6)A甲基转移酶 m^(6)A去甲基酶 m^(6)A阅读蛋白 病毒
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线粒体氧化应激及m6A表观遗传调控TRPC6钙通道在肾病综合征发病中的作用研究
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作者 姜丽娜 孔玮晶 丁瑛雪 《临床和实验医学杂志》 2024年第8期785-789,共5页
目的 初步探讨N6-甲基腺嘌呤(m6A)表观遗传修饰瞬时受体电位阳离子通道6(TRPC6)通道失调在肾病综合征发病中的作用及潜在机理。方法 按照随机数字表法将小鼠足细胞分为4组:对照组、叔丁基对苯二酚(TBHQ)组、嘌呤霉素氨基核苷(PAN)处理组... 目的 初步探讨N6-甲基腺嘌呤(m6A)表观遗传修饰瞬时受体电位阳离子通道6(TRPC6)通道失调在肾病综合征发病中的作用及潜在机理。方法 按照随机数字表法将小鼠足细胞分为4组:对照组、叔丁基对苯二酚(TBHQ)组、嘌呤霉素氨基核苷(PAN)处理组、TBHQ+PAN处理组。对照组为正常完全培养液,TBHQ组培养液中加入10 nmol/L TBHQ,PAN处理组培养液中加入PAN 50μg/mL,TBHQ+PAN处理组培养液中加入10 nmol/L TBHQ以及PAN 50μg/mL,刺激24 h收集细胞。应用膜片钳证实PAN损伤诱导TRPC6通道激活机理及1,4,5-肌醇三磷酸(IP3)受体拮抗剂TBHQ对电流的影响,检测对照组、PAN处理组、TBHQ组和TBHQ+PAN处理组细胞TRPC6通道电流变化。通过葡萄糖氧化酶(GO)建立足细胞氧化应激模型。另外按照随机数字表法将足细胞分为4组:空白对照组、GO组、姜黄素组、姜黄素+GO组。GO组给予GO 3.5 kU/L,姜黄素组给予Nrf2激动剂(姜黄素)40μmol/L,姜黄素+GO组给予姜黄素40μmol/L和GO 3.5 kU/L处理,给药处理8~12 h后收集细胞。检测各组Nrf2和特异性调控蛋白NAD(P)H:醌氧化还原酶1(NQO-1)、TRPC6及Transgelin蛋白和线粒体调控蛋白表达变化。通过SRAMP对TRPC6通道m6A位点进行精准预测,对PAN诱导足细胞损伤模型公共数据库GSE124622进行2次生物信息学分析。结果 对照组与TBHQ组电流比较,差异无统计学意义(P>0.05);与对照组比较,PAN处理组电流升高,而TBHQ+PAN组电流减小,差异均有统计学意义(P<0.05)。与空白对照组比较,GO组Nrf2、NQO-1、TRPC6及Transgelin蛋白表达均升高,差异均有统计学意义(P<0.01);与GO组比较,姜黄素+GO组Nrf2、NQO-1、TRPC6及Transgelin蛋白表达均降低,差异均有统计学意义(P<0.05)。与空白对照组比较,GO组线粒体调控蛋白Mfn2、Opa1蛋白表达均降低,Drp1蛋白表达升高,差异均有统计学意义(P<0.05);与GO组比较,姜黄素+GO组粒体调控蛋白Mfn2、Opa1蛋白表达升高,Drp1蛋白表达降低,差异均有统计学意义(P<0.05);空白对照组与姜黄素组TRPC6/Transgelin及线粒体调控蛋白表达比较,差异均无统计学意义(P>0.05)。TRPC6通道序列存在多个m6A修饰位点,均具有被甲基转移酶(METTL)3、METTL14、肾母细胞肿瘤1相关蛋白(WTAP)和去甲基化酶ALKB同源蛋白(ALKBH)、m6A去甲基化酶(FTO)调控的潜在可能。对12个m6A调节基因进行表达分析,发现m6A调节基因的表达在PAN诱导足细胞损伤中发生显著差异。结论 TRPC6介导钙离子内流可被氧化应激激活参与足细胞损伤,激活Nrf2可以减少钙过负荷所致线粒体损伤而保护足细胞。TRPC6序列中存在多个高m6A修饰靶点,肾病综合征发病机理可能通过m6A修饰足细胞TRPC6离子通道,m6A相关调控基因在肾病足细胞损伤中发生明显变化。 展开更多
关键词 肾病综合征 嘌呤霉素 氨基核苷 瞬时受体电位阳离子通道6 线粒体功能异常 N6-甲基腺嘌呤 m6A转移酶样3抑制剂
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定向电场下W_(6)C_(6)团簇的超卤素调制及非线性光学特性
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作者 蔡璧钧 段宇静 魏强 《原子与分子物理学报》 CAS 北大核心 2025年第3期72-76,共5页
本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且... 本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且在特定强度下,OEEF可以将W_(6)C_(6)团簇转变为超卤素.通过对EA值的非线性拟合可以实现对W_(6)C_(6)团簇的连续调制.进一步对不同外电场下W_(6)C_(6)团簇的最高占据分子轨道(HOMO)和最低未占据分子轨道(LUMO)能级进行分析,发现OEEF降低了W_(6)C_(6)团簇LUMO能级是其EA值增大的主因.此外,OEEF可以显著增大W_(6)C_(6)团簇的平均极化率和第一超极化率,尤其是第一超极化率,改变其非线性光学性质. 展开更多
关键词 定向外电场 超原子 密度泛函理论 NLO W_(6)C_(6)团簇
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血清淀粉样蛋白A、白介素6、肿瘤坏死因子α及微小RNA在脓毒症并发急性肾损伤患儿中的表达及预后评估价值研究
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作者 王林娜 张靖辉 《中国全科医学》 CAS 北大核心 2025年第3期293-298,共6页
背景 急性肾损伤(AKI)是脓毒症常见并发症,机体免疫-炎症指标是预测脓毒症并发AKI患儿预后的常用指标,目前从微小RNA(miR)方面评估的研究较少,有待临床探究。目的 探究血清淀粉样蛋白A(SAA)、白介素6(IL-6)、肿瘤坏死因子α(TNF-α)及mi... 背景 急性肾损伤(AKI)是脓毒症常见并发症,机体免疫-炎症指标是预测脓毒症并发AKI患儿预后的常用指标,目前从微小RNA(miR)方面评估的研究较少,有待临床探究。目的 探究血清淀粉样蛋白A(SAA)、白介素6(IL-6)、肿瘤坏死因子α(TNF-α)及miR在脓毒症并发AKI患儿中的表达,并分析其对预后的评估价值。方法 选取2020年3月—2023年3月平顶山市第一人民医院收治的100例脓毒症并发AKI患儿为观察组,另选取同期80例单纯脓毒症患儿为对照组。收集患者一般资料,酶联免疫吸附试验(ELISA)检测血清SAA、IL-6、TNF-α水平,采用实时荧光定量PCR法检测miR-21-3p、miR-182-5p、miR-128-3p相对表达量。比较两组序贯性器官功能衰竭(SOFA)评分、急性生理与慢性健康(APACHEⅡ)评分。采用Pearson相关性检验分析血清SAA、IL-6、TNF-α及miR水平与SOFA、APACHEⅡ评分的相关性。绘制受试者工作特征(ROC)曲线探究血清SAA、IL-6、TNF-α及miR水平对脓毒症并发AKI患儿死亡的预测价值并计算ROC曲线下面积(AUC)。结果 观察组SOFA评分、APACHEⅡ评分、血清SAA、IL-6、TNF-α、miR-21-3p、miR-182-5p、miR-128-3p水平均高于对照组(P<0.05)。住院28 d后观察组74例患儿生存,26例患儿死亡。生存患儿血清SAA、IL-6、TNF-α、miR-21-3p、miR-182-5p、miR-128-3p均低于死亡患儿(P<0.05)。血清SAA、IL-6、TNF-α、miR-21-3p、miR-182-5p、miR-128-3p与SOFA、APACHEⅡ评分均呈正相关(P<0.05)。ROC曲线结果显示联合预测的AUC为0.926(95%CI=0.856~0.969,P<0.05)。结论 脓毒症并发AKI患儿血清SAA、IL-6、TNF-α、miR-21-3p、miR-182-5p、miR-128-3p异常高表达,临床检测各项指标水平对患儿预后评估有较高价值及预警作用。 展开更多
关键词 脓毒症 急性肾损伤 血清淀粉样蛋白A 白介素6 肿瘤坏死因子Α
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Regulator of G protein signaling 6 mediates exercise-induced recovery of hippocampal neurogenesis,learning,and memory in a mouse model of Alzheimer’s disease
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作者 Mackenzie M.Spicer Jianqi Yang +5 位作者 Daniel Fu Alison N.DeVore Marisol Lauffer Nilufer S.Atasoy Deniz Atasoy Rory A.Fisher 《Neural Regeneration Research》 SCIE CAS 2025年第10期2969-2981,共13页
Hippocampal neuronal loss causes cognitive dysfunction in Alzheimer’s disease.Adult hippocampal neurogenesis is reduced in patients with Alzheimer’s disease.Exercise stimulates adult hippocampal neurogenesis in rode... Hippocampal neuronal loss causes cognitive dysfunction in Alzheimer’s disease.Adult hippocampal neurogenesis is reduced in patients with Alzheimer’s disease.Exercise stimulates adult hippocampal neurogenesis in rodents and improves memory and slows cognitive decline in patients with Alzheimer’s disease.However,the molecular pathways for exercise-induced adult hippocampal neurogenesis and improved cognition in Alzheimer’s disease are poorly understood.Recently,regulator of G protein signaling 6(RGS6)was identified as the mediator of voluntary running-induced adult hippocampal neurogenesis in mice.Here,we generated novel RGS6fl/fl;APP_(SWE) mice and used retroviral approaches to examine the impact of RGS6 deletion from dentate gyrus neuronal progenitor cells on voluntary running-induced adult hippocampal neurogenesis and cognition in an amyloid-based Alzheimer’s disease mouse model.We found that voluntary running in APP_(SWE) mice restored their hippocampal cognitive impairments to that of control mice.This cognitive rescue was abolished by RGS6 deletion in dentate gyrus neuronal progenitor cells,which also abolished running-mediated increases in adult hippocampal neurogenesis.Adult hippocampal neurogenesis was reduced in sedentary APP_(SWE) mice versus control mice,with basal adult hippocampal neurogenesis reduced by RGS6 deletion in dentate gyrus neural precursor cells.RGS6 was expressed in neurons within the dentate gyrus of patients with Alzheimer’s disease with significant loss of these RGS6-expressing neurons.Thus,RGS6 mediated voluntary running-induced rescue of impaired cognition and adult hippocampal neurogenesis in APP_(SWE) mice,identifying RGS6 in dentate gyrus neural precursor cells as a possible therapeutic target in Alzheimer’s disease. 展开更多
关键词 adult hippocampal neurogenesis Alzheimer’s disease dentate gyrus EXERCISE learning/memory neural precursor cells regulator of G protein signaling 6(RGS6)
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Electronic structure and ultraviolet spectra of p-C_(6)H_(4)-C_(20)
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作者 CHEN Xin 《原子与分子物理学报》 CAS 北大核心 2025年第3期21-28,共8页
Geometry optimization of p-C_(6)H_(4)-connected cyclo[20]carbon(p-C_(6)H_(4)-C_(20))was carried out at M062X/6-311G(d,p)level,three kinds of bond orders(Mayer,Laplacian,and Wiberg),electron-hole distributions,localize... Geometry optimization of p-C_(6)H_(4)-connected cyclo[20]carbon(p-C_(6)H_(4)-C_(20))was carried out at M062X/6-311G(d,p)level,three kinds of bond orders(Mayer,Laplacian,and Wiberg),electron-hole distributions,localized orbital locators(LOL),and infrared(IR)spectrum were also performed at the same level.Based on TD-DFT M062X/6-311G(d,p)method,the first 20 excited states and ultraviolet(UV)spectra of p-C_(6)H_(4)-C_(20) were calculated.Calculation results of π-electron delocalization analyses prove thatπ-electron delocalization of p-C_(6)H_(4)-C_(20) is more likely to occur on shorter C-C bonds rather than longer C-C bonds,and inside/outside of the ring plane rather than above/below the ring plane.Two absorption peaks of p-C_(6)H_(4)-C_(20) locate at about 319 nm and 236 nm,respectively. 展开更多
关键词 p-C_(6)H_(4)-C_(20) Bone orders UV spectrum Electron-hole analyses π-electron delocalization analyses
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Salsolinol as an RNA m~6A methylation inducer mediates dopaminergic neuronal death by regulating YAP1 and autophagy
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作者 Jianan Wang Yuanyuan Ran +5 位作者 Zihan Li Tianyuan Zhao Fangfang Zhang Juan Wang Zongjian Liu Xuechai Chen 《Neural Regeneration Research》 SCIE CAS 2025年第3期887-899,共13页
Salsolinol(1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline,Sal)is a catechol isoquinoline that causes neurotoxicity and shares structural similarity with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,an environme... Salsolinol(1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline,Sal)is a catechol isoquinoline that causes neurotoxicity and shares structural similarity with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,an environmental toxin that causes Parkinson's disease.However,the mechanism by which Sal mediates dopaminergic neuronal death remains unclear.In this study,we found that Sal significantly enhanced the global level of N~6-methyladenosine(m~6A)RNA methylation in PC12 cells,mainly by inducing the downregulation of the expression of m~6A demethylases fat mass and obesity-associated protein(FTO)and alk B homolog 5(ALKBH5).RNA sequencing analysis showed that Sal downregulated the Hippo signaling pathway.The m~6A reader YTH domain-containing family protein 2(YTHDF2)promoted the degradation of m~6A-containing Yes-associated protein 1(YAP1)mRNA,which is a downstream key effector in the Hippo signaling pathway.Additionally,downregulation of YAP1 promoted autophagy,indicating that the mutual regulation between YAP1 and autophagy can lead to neurotoxicity.These findings reveal the role of Sal on m~6A RNA methylation and suggest that Sal may act as an RNA methylation inducer mediating dopaminergic neuronal death through YAP1 and autophagy.Our results provide greater insights into the neurotoxic effects of catechol isoquinolines compared with other studies and may be a reference for assessing the involvement of RNA methylation in the pathogenesis of Parkinson's disease. 展开更多
关键词 ALKBH5 AUTOPHAGY FTO Hippo pathway m~6A Parkinson's disease RNA methylation SALSOLINOL YAP1 YTHDF2
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Mutual regulation of microglia and astrocytes after Gas6 inhibits spinal cord injury
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作者 Jiewen Chen Xiaolin Zeng +6 位作者 Le Wang Wenwu Zhang Gang Li Xing Cheng Peiqiang Su Yong Wan Xiang Li 《Neural Regeneration Research》 SCIE CAS 2025年第2期557-573,共17页
Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord injury.Microglia and astrocytes play key roles in the spinal cord injury micro-e... Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord injury.Microglia and astrocytes play key roles in the spinal cord injury micro-environment and share a close interaction.However,the mechanisms involved remain unclear.In this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming phenotypes.The expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord injury.In vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between them.We further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling pathway.This,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling pathways.In vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function recovery.Overall,Gas6 may play a role in the treatment of spinal cord injury.It can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord. 展开更多
关键词 ASTROCYTES AXL cell polarization GAS6 Hippo signal inflammatory micro-environment intercellular interaction MICROGLIA single-cell sequencing spinal cord injury
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Protein arginine methyltransferase-6 regulates heterogeneous nuclear ribonucleoprotein-F expression and is a potential target for the treatment of neuropathic pain
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作者 Xiaoyu Zhang Yuqi Liu +6 位作者 Fangxia Xu Chengcheng Zhou Kaimei Lu Bin Fang Lijuan Wang Lina Huang Zifeng Xu 《Neural Regeneration Research》 SCIE CAS 2025年第9期2682-2696,共15页
Protein arginine methyltransferase-6 participates in a range of biological functions,particularly RNA processing,transcription,chromatin remodeling,and endosomal trafficking.However,it remains unclear whether protein ... Protein arginine methyltransferase-6 participates in a range of biological functions,particularly RNA processing,transcription,chromatin remodeling,and endosomal trafficking.However,it remains unclear whether protein arginine methyl transferase-6 modifies neuropathic pain and,if so,what the mechanisms of this effect.In this study,protein arginine methyltransferase-6 expression levels and its effect on neuropathic pain were investigated in the spared nerve injury model,chronic constriction injury model and bone cancer pain model,using immunohistochemistry,western blotting,immunoprecipitation,and label-free proteomic analysis.The results showed that protein arginine methyltransferase-6 mostly co-localized withβ-tubulinⅢin the dorsal root ganglion,and that its expression decreased following spared nerve injury,chronic constriction injury and bone cancer pain.In addition,PRMT6 knockout(Prmt6~(-/-))mice exhibited pain hypersensitivity.Furthermore,the development of spared nerve injury-induced hypersensitivity to mechanical pain was attenuated by blocking the decrease in protein arginine methyltransferase-6 expression.Moreover,when protein arginine methyltransferase-6 expression was downregulated in the dorsal root ganglion in mice without spared nerve injury,increased levels of phosphorylated extracellular signal-regulated kinases were observed in the ipsilateral dorsal horn,and the response to mechanical stimuli was enhanced.Mechanistically,protein arginine methyltransferase-6 appeared to contribute to spared nerve injury-induced neuropathic pain by regulating the expression of heterogeneous nuclear ribonucleoprotein-F.Additionally,protein arginine methyltransfe rase-6-mediated modulation of hete rogeneous nuclear ribonucleoprotein-F expression required amino atids 319 to 388,but not classical H3R2 methylation.These findings indicated that protein arginine methyltransferase-6 is a potential therapeutic target fo r the treatment of peripheral neuro pathic pain. 展开更多
关键词 dorsal root ganglion heterogeneous nuclear ribonucleoprotein F neuropathic pain protein arginine methyltransferase-6 sensory neurons
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AAV2-PDE6B restores retinal structure and function in the retinal degeneration 10 mouse model of retinitis pigmentosa by promoting phototransduction and inhibiting apoptosis
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作者 Ruiqi Qiu Mingzhu Yang +5 位作者 Xiuxiu Jin Jingyang Liu Weiping Wang Xiaoli Zhang Jinfeng Han Bo Lei 《Neural Regeneration Research》 SCIE CAS 2025年第8期2408-2419,共12页
Retinitis pigmentosa is a group of inherited diseases that lead to retinal degeneration and photoreceptor cell death.However,there is no effective treatment for retinitis pigmentosa caused by PDE6B mutation.Adeno-asso... Retinitis pigmentosa is a group of inherited diseases that lead to retinal degeneration and photoreceptor cell death.However,there is no effective treatment for retinitis pigmentosa caused by PDE6B mutation.Adeno-associated virus(AAV)-mediated gene therapy is a promising strategy for treating retinitis pigmentosa.The aim of this study was to explore the molecular mechanisms by which AAV2-PDE6B rescues retinal function.To do this,we injected retinal degeneration 10(rd10)mice subretinally with AAV2-PDE6B and assessed the therapeutic effects on retinal function and structure using dark-and light-adapted electroretinogram,optical coherence tomography,and immunofluorescence.Data-independent acquisition-mass spectrometry-based proteomic analysis was conducted to investigate protein expression levels and pathway enrichment,and the results from this analysis were verified by real-time polymerase chain reaction and western blotting.AAV2-PDE6B injection significantly upregulated PDE6βexpression,preserved electroretinogram responses,and preserved outer nuclear layer thickness in rd10 mice.Differentially expressed proteins between wild-type and rd10 mice were closely related to visual perception,and treating rd10 mice with AAV2-PDE6B restored differentially expressed protein expression to levels similar to those seen in wild-type mice.Kyoto Encyclopedia of Genes and Genome analysis showed that the differentially expressed proteins whose expression was most significantly altered by AAV2-PDE6B injection were enriched in phototransduction pathways.Furthermore,the phototransductionrelated proteins Pde6α,Rom1,Rho,Aldh1a1,and Rbp1 exhibited opposite expression patterns in rd10 mice with or without AAV2-PDE6B treatment.Finally,Bax/Bcl-2,p-ERK/ERK,and p-c-Fos/c-Fos expression levels decreased in rd10 mice following AAV2-PDE6B treatment.Our data suggest that AAV2-PDE6B-mediated gene therapy promotes phototransduction and inhibits apoptosis by inhibiting the ERK signaling pathway and upregulating Bcl-2/Bax expression in retinitis pigmentosa. 展开更多
关键词 APOPTOSIS AAV2-PDE6B ERK1/2 gene therapy PHOTOTRANSDUCTION PROTEOMICS rd10 retinitis pigmentosa
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Enhanced autophagic clearance of amyloid-βvia histone deacetylase 6-mediated V-ATPase assembly and lysosomal acidification protects against Alzheimer's disease in vitro and in vivo
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作者 Zhimin Long Chuanhua Ge +5 位作者 Yueyang Zhao Yuanjie Liu Qinghua Zeng Qing Tang Zhifang Dong Guiqiong He 《Neural Regeneration Research》 SCIE CAS 2025年第9期2633-2644,共12页
Recent studies have suggested that abnormal acidification of lysosomes induces autophagic accumulation of amyloid-βin neurons,which is a key step in senile plaque formation.Therefore,resto ring normal lysosomal funct... Recent studies have suggested that abnormal acidification of lysosomes induces autophagic accumulation of amyloid-βin neurons,which is a key step in senile plaque formation.Therefore,resto ring normal lysosomal function and rebalancing lysosomal acidification in neurons in the brain may be a new treatment strategy for Alzheimer's disease.Microtubule acetylation/deacetylation plays a central role in lysosomal acidification.Here,we show that inhibiting the classic microtubule deacetylase histone deacetylase 6 with an histone deacetylase 6 shRNA or thehistone deacetylase 6 inhibitor valproic acid promoted lysosomal reacidification by modulating V-ATPase assembly in Alzheimer's disease.Fu rthermore,we found that treatment with valproic acid markedly enhanced autophagy.promoted clearance of amyloid-βaggregates,and ameliorated cognitive deficits in a mouse model of Alzheimer's disease.Our findings demonstrate a previously unknown neuroprotective mechanism in Alzheimer's disease,in which histone deacetylase 6 inhibition by valproic acid increases V-ATPase assembly and lysosomal acidification. 展开更多
关键词 Alzheimer's disease amyloid-β APP/PS1 mice autophagy cognitive impairment histone deacetylase 6 lysosomal acidification microtubule acetylation valproic acid V-ATPASE
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“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage
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作者 Yan Zhao Qiang Yuan +5 位作者 Liting Yang Guisheng Liang Yifeng Cheng Limin Wu Chunfu Lin Renchao Che 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期348-360,共13页
Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte reaction.However,their moderate unit-cellvolume expansion(gen... Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte reaction.However,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term cyclability.Here,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical properties.During Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O movement.Such superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries. 展开更多
关键词 NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization
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N^(6)-甲基腺苷修饰及其调控蛋白在脑缺血中的表达变化及意义
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作者 叶维贞 赵顺英 +5 位作者 姜鸣钰 黄秋茹 温少红 董雯 陈青芳 刘向荣 《中国卒中杂志》 北大核心 2024年第6期655-663,共9页
目的本研究通过探讨N^(6)-甲基腺苷(N^(6)-methyladenosine,m^(6)A)修饰及其调控蛋白在脑缺血小鼠中的表达变化,为脑缺血治疗的分子靶点研究提供参考。方法取60只雄性C57BL/6J小鼠,随机分为假手术组、脑缺血1 d组、脑缺血3 d组和脑缺血... 目的本研究通过探讨N^(6)-甲基腺苷(N^(6)-methyladenosine,m^(6)A)修饰及其调控蛋白在脑缺血小鼠中的表达变化,为脑缺血治疗的分子靶点研究提供参考。方法取60只雄性C57BL/6J小鼠,随机分为假手术组、脑缺血1 d组、脑缺血3 d组和脑缺血7 d组,每组各15只,采用线栓法制作右侧大脑中动脉梗死模型,于缺血1 h进行拔栓再灌注。通过RNA提取及斑点印迹实验检测小鼠缺血侧脑组织RNA m^(6)A水平;使用荧光定量逆转录PCR检测小鼠缺血侧脑组织甲基转移酶3(methyltransferase 3,Mettl3)、甲基转移酶14(methyltransferase 14,Mettl14)、FTOα-酮戊二酸酯依赖性双加氧酶(FTO alpha-ketoglutarate dependent dioxygenase,Fto)、RNA去甲基化酶alkB同源基因5(alkB homolog 5,RNA demethylase;Alkbh5)、YTH N^(6)-甲基腺苷RNA结合蛋白1(YTH N^(6)-methyladenosine RNA binding protein 1,Ythdf1)、Ythdf2和Ythdf3的mRNA表达水平;利用免疫印迹实验检测缺血侧脑组织Mettl3、Mettl14、Fto、Alkbh5、Ythdf1、Ythdf2和Ythdf3蛋白的表达水平;借助免疫荧光染色观察缺血侧脑组织梗死周边区神经元中Mettl3、Fto、Ythdf1、Ythdf2和Ythdf3蛋白的表达变化情况。结果与假手术组相比,脑缺血3 d组脑组织RNA的m^(6)A水平升高(1.620±0.339 vs.1.000±0.192,P=0.0343)。(1)甲基转移酶表达情况:脑缺血7 d组Mettl3mRNA水平降低(0.675±0.059 vs.1.000±0.131,P=0.0331);脑缺血1 d组Mettl3(0.548±0.107 vs.1.000±0.056,P=0.0398)、Mettl14(0.534±0.218 vs.1.000±0.018,P=0.0108)蛋白表达水平降低;脑缺血3 d组Mettl3(0.410±0.341 vs.1.000±0.056,P=0.0084)、Mettl14(0.429±0.283 vs.1.000±0.018,P=0.0026)蛋白表达水平也均下降;免疫荧光染色显示脑缺血3 d组梗死周边区神经元中Mettl3蛋白表达减少。(2)去甲基化酶表达情况:脑缺血1 d组(0.405±0.209 vs.1.000±0.142,P=0.0108)、脑缺血3 d组(0.530±0.125 vs.1.000±0.142,P=0.0412)Fto蛋白表达水平降低;免疫荧光染色显示脑缺血3 d组梗死周边区神经元中Fto表达减少。(3)m^(6)A结合蛋白表达情况:脑缺血1 d组Ythdf1mRNA水平降低(0.708±0.046 vs.1.000±0.117,P=0.0331),Ythdf3mRNA水平升高(1.473±0.093 vs.1.000±0.142,P=0.0012);脑缺血3 d组Ythdf1(0.593±0.240 vs.1.000±0.117,P=0.0034)、Ythdf2(0.664±0.177 vs.1.000±0.200,P=0.0100)mRNA水平降低,Ythdf3 mRNA水平升高(1.451±0.281 vs.1.000±0.142,P=0.0018);脑缺血1 d组Ythdf1(0.486±0.177 vs.1.000±0.091,P=0.0197)、Ythdf3(0.536±0.107 vs.1.000±0.125,P=0.0400)蛋白表达水平降低;脑缺血3 d组Ythdf1(0.404±0.299 vs.1.000±0.091,P=0.0079)、Ythdf2(0.279±0.189 vs.1.000±0.261,P=0.0136)、Ythdf3(0.450±0.220 vs.1.000±0.125,P=0.0157)蛋白表达水平均降低;免疫荧光染色显示脑缺血3 d组梗死周边区神经元中m6A结合蛋白Ythdf1、Ythdf2、Ythdf3表达均减少。结论小鼠脑缺血后可能由Fto表达下调导致m^(6)A水平升高,Ythdf1、Ythdf2、Ythdf3蛋白表达水平趋势基本一致,可能存在功能冗余。 展开更多
关键词 脑缺血 N^(6)-甲基腺苷修饰 N^(6)-甲基腺苷甲基转移酶 N^(6)-甲基腺苷去甲基化酶 N^(6)-甲基腺苷结合蛋白
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Enhancing m^(6)A modification in the motor cortex facilitates corticospinal tract remodeling after spinal cord injury
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作者 Tian Qin Yuxin Jin +5 位作者 Yiming Qin Feifei Yuan Hongbin Lu Jianzhong Hu Yong Cao Chengjun Li 《Neural Regeneration Research》 SCIE CAS 2025年第6期1749-1763,共15页
Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-met... Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-methyladenosine(m^(6)A) modifications are the most common form of epigenetic regulation at the RNA level and play an essential role in biological processes. However, whether m^(6)A modifications participate in corticospinal tract regeneration after spinal cord injury remains unknown. We found that expression of methyltransferase 14 protein(METTL14) in the locomotor cortex was high after spinal cord injury and accompanied by elevated m^(6)A levels. Knockdown of Mettl14 in the locomotor cortex was not favorable for corticospinal tract regeneration and neurological recovery after spinal cord injury. Through bioinformatics analysis and methylated RNA immunoprecipitation-quantitative polymerase chain reaction, we found that METTL14 regulated Trib2 expression in an m^(6)A-regulated manner, thereby activating the mitogen-activated protein kinase pathway and promoting corticospinal tract regeneration. Finally, we administered syringin, a stabilizer of METTL14, using molecular docking. Results confirmed that syringin can promote corticospinal tract regeneration and facilitate neurological recovery by stabilizing METTL14. Findings from this study reveal that m^(6)A modification is involved in the regulation of corticospinal tract regeneration after spinal cord injury. 展开更多
关键词 corticospinal tract remodeling epigenetic regulations locomotor cortex m^(6)A modification methyltransferase 14 protein(METTL14) mitogen-activated protein kinase neural regeneration spinal cord injury SYRINGIN TRIB2
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5G向6G演进过程中的发展困境及未来6G发展建议
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作者 刘桦 陈昕 +1 位作者 孟凡蓉 李为民 《智库理论与实践》 CSSCI 北大核心 2024年第4期98-109,共12页
[目的/意义]5G及下一代移动通信网络作为落实网络强国、数字中国建设的重要新型基础设施之一,为深化传统产业数字化转型提供了升级动力。5G行业应用在我国得到快速发展的同时,也面临诸多的问题与困境,这是5G向6G演进过程中无法绕开的关... [目的/意义]5G及下一代移动通信网络作为落实网络强国、数字中国建设的重要新型基础设施之一,为深化传统产业数字化转型提供了升级动力。5G行业应用在我国得到快速发展的同时,也面临诸多的问题与困境,这是5G向6G演进过程中无法绕开的关键。本文旨在借鉴5G经验,探索方法提高6G关键能力和行业需求的匹配程度,为6G走出5G困境寻求方向。[方法/过程]本文结合未来数字化场景针对6G关键能力的全面梳理,从6G发展需要破解的两大困境出发,基于专家调研获取的未来数字化场景针对6G关键能力的需求程度数据,构建6G典型场景需求评估及6G垂直行业潜在价值空间评估模型。在此基础上,识别6G在各行业应用发展中具有共性的、应优先关注或值得推广的典型场景,为6G在不同行业的多波次推进提供策略依据。[结果/结论]基于模型输出,本文提出了“6G发展以场景为引、按需部署,破解需求和效益的发展困境”“尽早推动6G商业闭环顶层设计,提升技术与需求匹配度”“统筹5G和6G发展,加强产业培育,基于5G为6G挖掘需求并验证”等6G发展建议,并指出从需求和效益出发,优先针对潜在价值高的特定场景的技术演进是未来6G可持续发展的重要研究方向。 展开更多
关键词 5G困境 6G关键能力 6G需求 6G典型场景 6G潜在价值空间评估
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黄芩苷对干酵母致热大鼠的解热作用及血清TNF-α、IL-1β、IL-6、PGE_(2)、cAMP和脑组织NF-κB表达的影响 被引量:4
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作者 吴迪 王清 +2 位作者 张殿文 李伟 李响 《中国中医药科技》 CAS 2024年第1期37-41,共5页
目的:观察黄芩苷对干酵母致热大鼠的解热作用并探讨其作用机制。方法:采用背部皮下注射干酵母构建大鼠发热模型,SD雄性大鼠随机分为正常对照,模型组,阳性组(阿司匹林,0.1 g/kg),黄芩苷高、中、低剂量组(160、80、40 mg/kg),连续给药3 d... 目的:观察黄芩苷对干酵母致热大鼠的解热作用并探讨其作用机制。方法:采用背部皮下注射干酵母构建大鼠发热模型,SD雄性大鼠随机分为正常对照,模型组,阳性组(阿司匹林,0.1 g/kg),黄芩苷高、中、低剂量组(160、80、40 mg/kg),连续给药3 d,测定各组大鼠肛温的变化;酶联免疫法(ELISA)检测血清肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)、白细胞介素-6(IL-6)、前列腺素E_(2)(PGE_(2))与环磷酸腺苷(cAMP)水平;Western Blot检测各组大鼠脑组织NF-κB p65(核转录因子-κB p65)蛋白表达。结果:黄芩苷高剂量组有显著解热效果(P<0.01),黄芩苷各剂量组均可不同程度降低大鼠血清TNF-α、IL-1β、IL-6、PGE 2和cAMP含量;与正常组比较,模型组脑组织NF-κB p65蛋白表达增多,黄芩苷高剂量组可明显降低大鼠脑组织NF-κB p65表达(P<0.05)。结论:黄芩苷可显著性降低干酵母引起的体温升高,解热机制可能与抑制TNF-α、IL-1β、IL-6、PGE_(2)与cAMP的分泌和减少脑组织NF-κB p65蛋白表达有关。 展开更多
关键词 黄芩苷 发热 解热作用 TNF-α IL-1β IL-6 PGE_(2) CAMP NF-κB p65 大鼠
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校园网络IPv6地址规划探析 被引量:1
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作者 罗全珍 张义平 +1 位作者 刘涛 王立 《科技创新与应用》 2024年第23期44-47,共4页
IPv6技术是互联网升级演进的必然趋势,是校园网络规划阶段需要重点考虑的环节。IPv6地址规划需要考虑路由性能、路由策略和安全等因素,合理的IP地址规划可以直观地识别节点属性,提高网络的可管理性。IPv6地址分配方法主要有单调分配、... IPv6技术是互联网升级演进的必然趋势,是校园网络规划阶段需要重点考虑的环节。IPv6地址规划需要考虑路由性能、路由策略和安全等因素,合理的IP地址规划可以直观地识别节点属性,提高网络的可管理性。IPv6地址分配方法主要有单调分配、稀疏分配、最适合分配、随机分配和前缀委托等。以作者所在学校为例,介绍IPv6地址的规划,期待能为有类似需求的单位提供一点有益的探索和借鉴。 展开更多
关键词 校园网络 IPV6 地址规划 DHCPV6 最适合分配
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miR-216a和CAPN6基因过表达人宫颈癌细胞系HeLa增殖迁移侵袭变化及靶向关系
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作者 张贤雨 马欢 +5 位作者 宋凤丽 刘晓玉 李植燕 原娜 郝晓慧 张志林 《山东医药》 CAS 2024年第18期21-25,共5页
目的观察微小RNA-216a(miR-216a)和钙蛋白酶6(CAPN6)基因过表达的人宫颈癌细胞系HeLa增殖、迁移、侵袭变化及靶向关系,探讨miR-216a对HeLa细胞增殖迁移侵袭影响的作用机制。方法取对数生长期HeLa细胞,分为一、二、三、四、五组,一组转染... 目的观察微小RNA-216a(miR-216a)和钙蛋白酶6(CAPN6)基因过表达的人宫颈癌细胞系HeLa增殖、迁移、侵袭变化及靶向关系,探讨miR-216a对HeLa细胞增殖迁移侵袭影响的作用机制。方法取对数生长期HeLa细胞,分为一、二、三、四、五组,一组转染miR-216a mimic,二组转染pcDNA3.1-CAPN6质粒,三组顺序转染miR-216a mimic、pcDNA3.1-CAPN6,四组转染pcDNA3.1,五组转染miR-216a mimic NC,培养48 h时分别采用CCK-8法、划痕愈合实验、Transwell试验观察各组细胞的增殖迁移侵袭情况,培养24 h时采用qRT-PCR法检测各组细胞miR-216a、采用WesternBlotting法检测各组细胞CAPN6及信号转导子与激活子3(STAT3)蛋白。取对数生长期HeLa细胞分为四组:A组细胞顺序转染miR-216a mimic、pGL3-CAPN6-WT质粒,B组细胞顺序转染miR-216a mimic、pGL3-CAPN6-MUT质粒,C组细胞顺序转染miR-216amimicNC、pGL3-CAPN6-WT,D组细胞顺序转染miR-216amimicNC、pGL3-CAPN6-MUT,培养36 h时收集各组细胞,采用双荧光素酶报告基因检测试剂盒测算各组细胞相对荧光素酶活性。结果与五组相比,培养48 h时一组细胞增殖活性及划痕前缘迁移距离百分比低、侵袭细胞数少(P均<0.01);与四组相比,二组细胞增殖活性及划痕前缘迁移距离百分比高、侵袭细胞数多(P均<0.01);与一组相比,三组细胞增殖活性及划痕前缘迁移距离百分比高、侵袭细胞数多(P均<0.01);与二组相比,三组细胞增殖活性及划痕前缘迁移距离百分比低、侵袭细胞数少(P均<0.01)。与五组相比,一组细胞miR-216a相对表达量高(P<0.01)。与四组相比,培养24 h时二组细胞CAPN6蛋白、p-STAT3/STAT3相对表达量高,三组细胞表达CAPN6蛋白、p-STAT3/STAT3相对表达量低;与五组相比,一组细胞CAPN6蛋白、p-STAT3/STAT3相对表达量低;与一组相比,三组细胞CAPN6蛋白、p-STAT3/STAT3相对表达量高。与B组相比,A组细胞荧光素酶活性低(P<0.05)。结论miR-216a过表达可抑制HeLa细胞的增殖侵袭和迁移。HeLa细胞中miR-216a与CAPN6基因存在靶向关系。miR-216a可能通过调控CAPN6基因表达,抑制HeLa的增殖、迁移及侵袭。 展开更多
关键词 微小RNA 微小RNA-216a 钙蛋白酶6 细胞增殖 细胞侵袭 细胞迁移 宫颈癌
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