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1.
应用免疫组化PAP法和TUNEL凋亡染色法,对小鼠胚胎及生后1~5天食管肌层的发育进行了研究,以阐明小鼠食管肌层的分化发育特点。结果显示:α-平滑肌肌动蛋白(α-SMA)是食管肌层最先表达的标志蛋白。ED12(胎龄12天)的食管上段,α-SMA表达限于后壁间充质细胞。中段以下,可见α-SMA弱阳性细胞形成不连续环形围绕食管腔。ED13,  相似文献   

2.
目的 探讨血管紧张素(Ang)Ⅱ与其介导的蛋白酪氨酸激酶JAK2信号通路在急性缺血再灌注肾损伤模型中发生的肾小管上皮细胞逆向分化的作用机制.方法 (1)建立Wistar大鼠急性缺血再灌注肾损伤模型,采用放射免疫法检测肾脏局部AngⅡ的水平变化,采用免疫组织化学ABC法和RT-PCR,观察间充质细胞表面标记α-平滑肌肌动蛋白(α-SMA)的表达.(2)模拟高、中、低浓度的肾素-血管紧张素系统(RAS)环境,体外观察培养的肾小管上皮细胞(NRK-52E)逆向分化的情况.(3)先后阻断AngⅡ受体(AT2R)及其介导的Ang Ⅱ信号转导通路的JAK2,研究AngⅡ与JAK2通路对肾小管上皮细胞逆向分化的影响.结果 (1)肾脏缺血再灌注损伤后0、24、48、72、96、120 h,局部AngⅡ含量持续增高,分别为(406.7±106.1)、(463.0±112.9)、(526.6±128.3)、(649.5±131.5)、(875.4±150.2)、(980.8±155.2)ng/L,P<0.05.(2)缺血再灌注后48 h,肾小管上皮细胞开始表达α-SMA mRNA及蛋白质.(3)高浓度(10-7mol/L)Ang Ⅱ刺激可诱导体外培养的肾小管上皮细胞表达α-SMA,且呈剂量和时间依赖性.10-9,mol/L浓度AngⅡ刺激30 min时,α-SMA表达水平最高.无论是阻断AT2R抑或JAK2信号通路,肾小管上皮细胞表达α-SMA均明显受到抑制.结论 急性缺血再灌注损伤时肾小管上皮细胞可向间充质细胞逆向分化,局部RAS启动与其密切相关.AngⅡ可能通过AT2R及其介导的JAK2信号通路促发肾小管细胞的逆向分化.  相似文献   

3.
目的: 探讨小鼠胚胎干细胞在体外分化心肌样细胞过程中αMHC、Anf、MLC2v基因的表达情况以及分化的心肌样细胞的电生理特点。 方法: 将转染PαMHC-EGFP小鼠D3胚胎干细胞系,体外诱导分化心肌样细胞,应用RT-PCR检测0 d、3 d、5 d、7 d、10 d、14 d拟胚体(EB)细胞中αMHC、Anf、 MLC2v基因的表达情况,同时应用膜片钳技术,观察心肌样细胞的电生理特性。 结果: 在EB形成的7d和8d可见EB内出现有绿色荧光蛋白表达的心肌样细胞群;RT-PCR结果显示αMHC基因表达在EB体形成第7 d,而在10 d、14 d跳动的心肌样细胞中该基因表达增强(P<0.05),而Anf、 MLC2v基因的表达仅出现在心肌样细胞;膜片钳记录的心肌样细胞动作电位显示,73.5%(n=34)的细胞记录到典型心房肌细胞动作电位[APD90=(78.4±3.1)ms];20.5%细胞表现为起搏细胞动作电位[APD90=(112.6±5.5)ms];1个细胞显示了典型的心室肌细胞动作电位的特征(APD90=200 ms)。 结论: 在心肌样细胞分化的早期可见αMHC、Anf、 MLC2v基因的表达,这3种基因可为心肌发育过程中的特征性基因并对心肌发育起调节作用。而此干细胞系分化的心肌样细胞主要为心房肌细胞和起搏细胞。  相似文献   

4.
IL-18对肾小管上皮细胞表型转化的影响   总被引:1,自引:0,他引:1  
目的:研究IL-18对体外培养肾小管上皮细胞表型转化的影响,以明确IL-18在慢性肾脏疾病中的可能作用机制。方法:应用体外细胞培养技术培养人肾小管上皮细胞侏(HK-2)。应用RT-PCR技术检测α-平滑肌肌动蛋白(α-SMA)、转化生长因子-β1(TGF-β1)mRNA水平,用免疫细胞化学方法(ICC)及Western blot技术分别检测IL-18对HK-2细胞表达仪-SMA蛋白的影响。结果:(1)IL-18可促进HK-2细胞表达α-SMA、TGF-β1 mRNA,且两者之间呈正相关(P〈0.05)。(2)IL-18增加α-SMA阳性HK-2细胞百分数(P〈0.05)。(3)IL-18使HK-2细胞α-SMA蛋白表达水平增加。结论:IL-18可剂量和时间依赖性地促进肾小管上皮细胞转分化为肌成纤维细胞,促进肾间质纤维化。  相似文献   

5.
目的:比较胚胎体、胚胎体-细胞单层和细胞单层3种细胞培养方式对小鼠胚胎干细胞(ES细胞)分化为胰岛素分泌细胞的诱导效果方法:应用胰高血糖素样肽-1(GLP-1)、β细胞素(betacellulin)、激活素A(activin A)、碱性成纤维细胞生长因子(bFGF)和尼克酰胺(nicotinamide),分别以胚胎体、胚胎体-细胞单层和细胞单层3种细胞培养方式诱导小鼠ES细胞30 d后,应用RT-PCR、双硫腙(DTZ)染色和免疫组化检测分化细胞胰岛素表达,以流式细胞仪检测胰岛素阳性细胞百分比结果:3种细胞培养方式诱导的分化细胞均可见DTZ染色和胰岛素免疫组化染色阳性细胞,RT-PCR检测到胰岛素和其它一些胰岛相关基因mRNA表达,胚胎体-细胞单层方式胰岛素mRNA表达最强,胚胎体方式次之,细胞单层方式最弱。胚胎体-细胞单层方式的胰岛素阳性细胞百分比高于胚胎体方式(P<0.01),后者又高于细胞单层方式(P<0.01)结论:采用胚胎体-细胞单层方式诱导可更好促进小鼠ES细胞分化为胰岛素分泌细胞。  相似文献   

6.
目的观察α-横纹肌肌节肌动蛋白(α-SCA)、α-平滑肌肌动蛋白(ct-SMA)和中间丝结蛋白在小鼠心脏发育过程中的时空表达特征,以探讨这些蛋白质表达与胚胎及生后小鼠心脏成熟的关系。方法用抗α-SCA、抗α-SMA及抗结蛋白单克隆抗体对胚胎及生后小鼠心脏连续切片进行染色。结果胎龄9d,心室和流出道α-SCA、α-SMA表达较强,而结蛋白表达较弱。在心房α-SCA、α-SMA的表达限于背侧壁和腹侧壁,静脉窦仅见少许α-SCA弱阳性细胞。心房和静脉窦则无结蛋白表达。α-SCA、α-SMA和结蛋白的表达于胎龄12d达高峰。较高水平的α-SCA表达将持续到生后。心脏各部α-SMA和结蛋白表达于胎龄12d后逐渐下降,但在右心室表达持续时间较长。出生后,结蛋白表达主要集中于明带Z线和闰盘。结论α-SMA和结蛋白在小鼠胚胎心脏表达的时空差异性表明小鼠胚胎心脏不同部位发育成熟的时问有差异,右心室成熟较慢。α-SMA表达可能与早期胚胎心脏的缓慢蠕动收缩有关。肌节的发育成熟需要较高的结蛋白表达。  相似文献   

7.
目的:体外研究多发性骨髓瘤(MM)患者尿本周氏蛋白(BJP)对肾小管上皮细胞(TEC)的转分化作用以探讨MM肾损害的部分机理。方法:将自MM患者尿中提取的κ和λ型BJP各5例以不同浓度与大鼠NRK52E株TEC共同培养72小时,通过倒置显微镜、透射电镜观察TEC形态学改变;采用细胞免疫组织化学法研究细胞骨架标志:细胞角蛋白-18、波形蛋白、α平滑肌肌动蛋白(α-SMA)表达的改变。结果:培养72小时后,光镜下部分细胞拉长呈梭形;透射电镜下细胞变得肥大,细胞中出现与细胞长轴平行的微丝束和致密体;随BJP的浓度增加,NRK52E细胞角蛋白-18表达率逐渐减少,波形蛋白和α-SMA表达率逐渐增加。结论:BJPκ与BJPλ均有促进NRK52E转分化的作用,且随着BJP浓度增加而增强。  相似文献   

8.
目的:研究小鼠诱导多能干细胞(i PS细胞)在体外自发性分化和神经定向分化过程中的基因表达谱的特性。方法:在体外将i PS细胞分别进行形成类胚胎小体后自发性分化及成骨蛋白抑制剂Noggin诱导神经定向分化后,通过实时荧光定量PCR(q PCR)测定在分化过程中i PS细胞分化相关基因表达的变化。结果:i PS细胞形成类胚胎小体后胚胎外胚层标志基因(GFAP,Map2和Tu J1)及内胚层标记基因(Foxa2,GATA4和Sox17)的表达随分化而迅速增加,但中胚层标记基因(Bmp4,BRA,FGF5)表达水平变化不明显。在神经定向分化过程中,i PS细胞的神经标志物基因(Map2,Neu N,Tu J1和Sox1)及线粒体相关基因(12s,ND3,ND5,ND6、Cytb和Cox1)的表达都逐渐增加,且两者具有相同的增长趋势。结论:在自发性分化过程中小鼠i PS细胞具有自发向外胚层和内胚层分化的趋势;在神经定向分化过程中,i PS细胞的线粒体相关基因表达随着分化表达逐渐增加,并与神经细胞标记基因具有正相关性,表明线粒体的功能在i PS细胞神经定向分化中发挥重要作用。  相似文献   

9.
目的:探讨三七总皂苷(total saponins of panax notoginseng, PNS)对马兜铃酸I(aristolochic acid I,AAI)诱导的人肾小管上皮细胞株HK-2转分化的影响。方法:应用倒置相差显微镜观察HK-2细胞形态学变化;免疫组织化学方法检测α-平滑肌肌动蛋白(α-smooth muscle actin, α-SMA)的表达;ELISA法测定培养细胞上清液中转化生长因子-β1(transforming growth factor-β1, TGF-β1)的含量。结果:AA I诱导组HK-2细胞从原有典型的上皮细胞形态转变为长梭形肌成纤维细胞形态;胞浆内大量表达α-SMA,其积分光密度值增加(P<0.05);细胞培养上清液中TGF-β1含量均增加,且呈时间依赖性(P<0.05)。不同剂量PNS治疗可减轻AA I诱导的细胞形态学改变,不同程度的抑制α-SMA的表达和TGF-β1的分泌,且呈剂量依赖性(P<0.05)。PNS对照组HK-2细胞形态学、α-SMA表达和TGF-β1分泌与空白对照组比较均无明显变化。结论:AA I可通过促进TGF-β1的分泌诱导肾小管上皮细胞转分化,促进细胞外基质α-SMA的合成;PNS可抑制AA I诱导的肾小管上皮细胞转分化作用,减少α-SMA的表达,该作用可能是通过抑制TGF-β1表达实现的。  相似文献   

10.
目的: 研究鼠巨细胞病毒(MCMV)感染对体外培养神经干细胞(NSCs)分化及分化基因表达的影响,探讨CMV先天感染致脑发育异常的机制。方法: 体外分离培养和鉴定BALB/c胎鼠NSCs,检测细胞分化潜能,用感染复数(MOI)为5、1和0.1 MCMV smith毒株感染NSCs并进行分化培养,倒置显微镜下观察细胞形态学改变,流式细胞术检测分化细胞比率,免疫荧光法观察NSCs及其分化细胞标记物nestin、GFAP和NSE表达的变化,采用MCMV 早期抗原(EA)示踪感染过程(MOI=1),实时定量RT-PCR检测分化早期NSCs Wnt信号途径关键分化基因Neurog2、Myc及Ccnd1 mRNA水平的动态变化。结果: 体外培养的NSCs呈球样生长,神经干细胞特异性标记nestin表达阳性,并可进一步分化为NF-200阳性的神经元和GFAP阳性的星形胶质细胞;分化培养后,感染组NSCs不能贴壁分化生长并逐渐出现肿胀,细胞nestin表达下调缓慢并显著高于正常对照组,GFAP和NSE表达显著低于正常对照组(P<0.05),可检测到MCMV EA(早期抗原)的阳性表达;分化培养3-9 d,感染组nestin阳性细胞比率显著高于正常对照组,GFAP和NSE阳性细胞比率显著低于正常对照组(P<0.05);感染组Neurog2 mRNA水平在分化培养后第1 d明显低于正常对照组(P<0.05),感染组Myc mRNA表达水平在第1-4 d显著低于正常组(P<0.05),感染组Ccnd1 mRNA水平在第0.5-1 d明显低于正常组;感染组和正常组的差异随病毒MOI的增加而更明显。结论: (1)MCMV感染可明显抑制NSCs向神经元和星形胶质细胞方向分化,导致分化细胞比率减少;(2)MCMV可下调或干扰NSCs Wnt信号途径分化基因Neurog2、Myc和Ccnd1的表达;(3)MCMV抑制NSCs分化及其分化基因表达的效应与MOI大小存在一定量效依赖关系;(4)MCMV可能通过抑制NSCs分化基因的表达来抑制其分化,这可能是CMV感染致脑发育异常的重要机制之一。  相似文献   

11.
Epithelial–mesenchymal transition (EMT) of tubular epithelial cells (TECs) is commonly considered as the major mechanism leading to renal fibrosis in chronic kidney diseases (CKD) injury. We raise the hypothesis that EMT in adult kidney may be an event of “atavistic” phenotypic transition, which mimics but reverses the genetic and cellular processes of development of renal tubules. Transformed TECs may be regarded as induced mesenchymal stem-like cells, representing a cellular self-adaptation when in acute or chronic injury. The reasons are as follows: (1) Embryonic gene WT1 and Pax2, which govern tubule development, have been found to re-express during tubular EMT when facing injury. (2) The common factors that induce EMT in vitro, like IL-1, angiotension II and hypoxia could also promote WT1 and/or Pax2 re-expression. (3) Expression of WT1 and Pax2 are found to be associated with progenitor cells. (4) Beside embryonic gene WT1 and Pax2, we also found that some stem cell markers like CD133 were expressed during EMT process. (5) The process of EMT is not only take place in chronic kidney injury (CKD), but also in acute kidney injury (AKI) as well. (6) The phenotype transition of TECs and genetic event during AKI are entirely consistent with what happened in CKD, but the outcome is completely different. Thus, we thought tubular injury of CKD and AKI may share a common initiative repair mechanism: tubular EMT, that is TECs are transformed into induced mesenchymal stem-like cells, and then interpret the injurious signal differently in acute versus chronic conditions, so as to possess a divergent fates, tubular regeneration or fibrosis formation, depending on a different microenvironment or the duration of the injury. In this sense, tubular EMT could be purposefully orientated into a constructively pathway that repair kidney injury via tubular regeneration, matrix remodeling and tissue structure and function restoration.  相似文献   

12.
Interstitial fibrosis is regarded as the common final pathway in chronic renal failure. Myofibroblasts play an important role in the renal fibrosis through producing extracellular matrices. In addition to expressions of cytoskeletons such as vimentin, desmin and α-smooth muscle actin (α-SMA), Thy-1 expression was investigated in cisplatin-induced rat renal interstitial fibrosis, to clarify the characteristics of myofibroblasts. Immunohistochemically, myofibroblasts in the renal fibrotic lesions reacted to vimentin, desmin and α-SMA in varying degrees, and the expression degrees were increased with advancing fibrosis. Vimentin expression was the greatest and the increased expression retained even in scar at end stages, whereas desmin and α-SMA expressions were almost completely decreased in scar. In double immunofluorescence, there were myofibroblasts reacting to both vimentin/desmin, desmin/α-SMA or α-SMA/vimentin, indicating that renal myofibroblasts can simultaneously express different cytoskeletons. Thy-1 expression in renal myofibroblasts was increased according to progressing fibrosis; however, the increased expression was decreased in scar, similar to desmin and α-SMA expressions. Some myofibroblasts expressing Thy-1 reacted simultaneously to vimentin or desmin, but there were no cells reacting to both Thy-1 and α-SMA. Because well-differentiated myofibroblasts are characterized mainly by α-SMA expression and the pericytes (immature stromal stem cells) showed a positive reaction to Thy-1, renal myofibroblasts might be originated from immature mesenchymal cells through loosing Thy-1 expression. This study for the first time shows that renal myofibroblasts can variously exhibit such mesenchymal markers as vimentin, desmin, α-SMA and Thy-1; particularly, Thy-1 immunohistochemistry would be used to detect myofibroblasts at early stages in analyzing chemically induced renal lesions.  相似文献   

13.
目的:探讨黄芪多糖对糖尿病肾病肾小管上皮细胞凋亡、转分化及ROS 含量的影响。方法:HK-2 细胞分为低糖组、高糖组和黄芪多糖+高糖组,处理细胞48 h 后,CCK-8 实验检测细胞增殖;流式细胞仪检测细胞凋亡及ROS 含量;Western blot 检测E-cadherin、α-SMA、STAT1、STAT3、p-STAT1、p-STAT3 蛋白表达。结果:高糖组细胞存活率显著低于低糖组(P<0.01),细胞凋亡率、ROS 含量及E-cadherin、α-SMA、p-STAT1、p-STAT3 蛋白表达均显著高于低糖组(P<0.01),高糖+黄芪多糖组细胞存活率显著高于高糖组,细胞凋亡率、ROS 含量及E-cadherin、α-SMA、p-STAT1、p-STAT3 蛋白表达均显著低于高糖组(P<0.01)。结论:黄芪多糖可促进高糖诱导的肾小管上皮细胞增殖,抑制细胞凋亡及转分化,其机制与下调JAK/ STAT 信号通路有关。  相似文献   

14.
目的:探讨1,25(OH)2D3对甲状旁腺素(PTH)诱导的肾小管上皮细胞转分化和转化生长因子-β1(TGF-β1)表达的影响。方法:人肾小管上皮细胞(HK-2细胞)培养在含50 mL/L FCS的DMEM/F12培养液中。对照组:加入等体积含50 mL/L FCS的DMEM/F12培养液;PTH刺激组:加入终浓度为10-10 mol/L PTH的含50 mL/L FCS的DMEM/F12培养液;PTH+1,25(OH)2D3干预组:加入10-10 mol/L PTH,同时加入不同浓度(10-10、10-9、10-8、10-7 mol/L)的1,25(OH)2D3。刺激HK-2细胞48 h。半定量RT-PCR法检测细胞中α-平滑肌肌动蛋白(α-SMA)和TGF-β1的基因表达;Western blot法检测细胞中α-SMA和TGF-β1的蛋白表达;免疫细胞化学法检测细胞中α-SMA的表达;ELISA法检测细胞培养上清液中TGF-β1的含量。结果:半定量RT-PCR结果显示,对照组HK-2细胞中几乎无α-SMA的mRNA表达,仅有少量的TGF-β1 mRNA表达;PTH刺激组α-SMA和TGF-β1mRNA表达量与对照组比较明显增加;PTH+1,25(OH)2D3干预组表达量比PTH刺激组显著降低,且随着1,25(OH)2D3浓度的升高呈一定的剂量依赖性(P<0.05)。Western blot结果显示,对照组HK-2细胞中无α-SMA的蛋白表达,仅有少量的TGF-β1蛋白表达;10-10 mol/L的PTH能够明显诱导HK-2细胞中α-SMA的蛋白表达,增加TGF-β1的蛋白表达量;PTH+1,25(OH)2D3干预组,α-SMA和TGF-β1的蛋白表达量比PTH刺激组显著降低(P<0.05)。免疫细胞化学法结果显示,对照组几乎无α-SMA阳性表达的细胞,PTH刺激组可见大量细胞α-SMA表达阳性;PTH+1,25(OH)2D3干预组α-SMA表达阳性的细胞数明显低于PTH刺激组(P<0.05)。ELISA结果显示,对照组细胞上清液中可检测到少量的TGF-β1,PTH刺激组含量显著升高,PTH+1,25(OH)2D3干预组与PTH刺激组比较含量明显降低(P<0.05)。结论:1,25(OH)2D3能够部分拮抗PTH诱导的HK-2细胞转分化和TGF-β1的表达。  相似文献   

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16.
Mature tubular epithelial cells in the adult kidney can undergo epithelial-mesenchymal transition (EMT), a phenotypic change that is linked to the pathogenesis of renal interstitial fibrosis. EMT may be considered the reverse of mesenchymal-epithelial transition, which occurs during normal kidney development. The Wilms' tumor suppressor gene WT1 and the paired box 2 gene Pax2 are needed to induce mesenchymal-epithelial transition and play key roles in the progression of nephrogenesis. However, until now, WT1 and Pax2 have not been tested for their direct involvement in the process of renal tubular EMT. In this study, we explored the potential roles of WT1 and Pax2 in EMT that is induced in the remnant kidney of rats following 5/6 nephrectomy. We also examined WT1 and Pax2 in cultured renal tubular epithelial (NRK52E) cells treated with interleukin-1α and investigated the effects of blocking EMT using RNA interference. We showed that WT1 and Pax2 were re-expressed in the EMT models, and these were accompanied by decreased expression of E-cadherin and increased expression of vimentin, Snail and α-smooth muscle actin. Silencing WT1 and Pax2 by RNA interference blocked the interleukin-1α-induced EMT in the NRK52E cells, as reflected in the suppression of α-SMA and Snail expression, the restoration of E-cadherin expression and normal cell morphology. Our experiments suggested that the re-expression of WT1 and Pax2 in the tubular epithelial cells plays important roles in the promotion of EMT, and there may be therapeutic value in silencing Pax2 and WT1 to prevent or reverse renal fibrosis.  相似文献   

17.
目的:观察外周血单核巨噬细胞(MO/MAC)条件培养基(M-CM)对肾小管上皮细胞(RTEC)直接作用的生物学效应并探讨可能的作用机制。方法:应用正常人外周血M-CM刺激人近端肾小管上皮细胞(HK-2),以[3H]-TdR掺入法检测HK-2细胞DNA合成、Westernblot法检测骨桥蛋白(OPN)和α-平滑肌肌动蛋白(α-SMA)表达、间接抑制ELISA法检测纤连蛋白(FN)分泌。进一步采用白细胞介素-10(IL-10)和转化生长因子-β1(TGF-β1)中和抗体进行拮抗。结果:①M-CM可促进HK-2细胞DNA合成、α-SMA表达及FN分泌。②TGF-β1中和抗体(5mg/L)与M-CM同时作用于HK-2细胞,其α-SMA表达和FN分泌均明显低于M-CM单独作用组。③IL-10(20μg/L)与M-CM同时作用组的HK-2细胞,α-SMA表达和FN分泌亦明显低于M-CM组;IL-10预孵育MO/MAC组,HK-2细胞α-SMA表达也明显低于M-CM组。结论:单核巨噬细胞可直接诱导肾小管上皮细胞增殖、表型转化以及分泌细胞外基质增加;其分泌的TGF-β1及炎性细胞因子可能参与介导上述效应。  相似文献   

18.
目的:探讨成纤维细胞(FB)向肌成纤维细胞( MFB)转分化在系统性硬化症(SSc)发病机制中的作用和H2松弛素( H2-RLX)在SSc中的抗纤维化作用机制.方法:体外培养SSc患者皮损和正常皮肤FB及鉴定;免疫细胞化学法定性、ELISA法定量检测FB中α-平滑肌肌动蛋白(α-SMA)而了解MFB比重;施加并观察H2-RLX对SSc FB增殖和转分化为MFB的影响.结果:两组FB的细胞形态无明显不同;SSc组α-SMA阳性率均值高于对照组(P<0.01);随培养时间的延长,两组α-SMA量均渐增多(P均<0.01),但在培养的24、48、72 h,SSc组α-SMA量分别高于对照组(P均<0.05);H2-RLX 1 μg/L对FB增殖和α-SMA量无明显影响,而10 μg/L和100 μg/L则完全地抑制FB增殖和α-SMA量(P均<0.05),以100 μg/L时抑制作用最强.结论:SSc患者皮损来源的FB存在强烈地向MFB转分化的特性,H2-RLX则可通过抑制FB增殖及转分化为MFB而在SSc中发挥抗纤维化作用.  相似文献   

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