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11.
AIM: To explore the target relationship between microRNA-140-3p (miR-140-3p) and programmed cell death ligand 1 (PD-L1) and their effect on the viability, migration and invasion of non-small-cell lung cancer A549 cells.METHODS: RT-qPCR was used to detect the miR-140-3p expression in HLF-1, A549 and H1299 cells, and then the A549 cells with the most significant difference were selected as the subsequent research object. TargetScan software and dual-luciferase reporter assay were performed to predict and confirm the target relationship between miR-140-3p and PD-L1. RT-qPCR and Western blot were used to determine the effects of miR-140-3p mimic and inhibitor on PD-L1 expression level. MTT assay was used to detect the viability of A549 cells. Transwell assay was performed to detect the migration and invasion abilities of the A549 cells.RESULTS: miR-140-3p was significantly down-regulated in the A549 cells and H1299 cells (P<0.05). Transfection with miR-140-3p mimic decreased the expression of PD-L1 and inhibited the viability, migration and invasion of the A549 cells. Transfection with pcDNA3.0-PD-L1 reversed the inhibitory effect of miR-140-3p on the viability, migration and invasion of the A549 cells.CONCLUSION: miR-140-3p inhibits the viability, migration and invasion of A549 cells by targeting PD-L1.  相似文献   
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AIM:To investigate the effect of proline-spirooxindole on the viability and apoptosis of human non-small-cell lung cancer A549 cells. METHODS:The effect of proline-spirooxindole on the viability of A549 cells was determined by CCK-8 assay. The apoptosis was analyzed by flow cytometry. The effects of proline-spirooxindole on the expression of PARP and p53 and the phosphorylation of mTOR were determined by Western blot. RESULTS:After A549 cells were treated with proline-spirooxindole (25, 50 and 100 mg/L), the cell viability was decreased (P<0.01) compared with DMSO control group. The apoptotic rate was increased compared with DMSO control group (P<0.01). The protein expression of p53 was up-regulated, the increased apoptotic protein cleaved PARP was observed, and the phosphorylation of mTOR was inhibited (P<0.01). CONCLUSION:Proline-spirooxindole inhibits the viability of A549 cells and induces apoptosis, which may be related to the phosphorylation of mTOR.  相似文献   
13.
热处理对低温胁迫下黄瓜活性氧代谢和膜脂组分的影响   总被引:1,自引:0,他引:1  
为探讨热处理减轻黄瓜果实低温冷害的作用机理,本试验研究了47℃热水浸泡5 min处理对黄瓜果实在4℃贮藏期间活性氧代谢和膜脂组分的影响。结果表明,47℃热水5 min处理可显著抑制黄瓜果实冷害的发生,贮藏15 d后果实冷害指数较对照(CK)低20.87%。此外,热处理还可抑制黄瓜相对电导率及丙二醛(MDA)含量的上升,提高黄瓜果实超氧化物歧化酶(SOD)、过氧化物酶(DOD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)的活性,抑制超氧阴离子($\mathop{{O}}_{2}^{{\mathop{}_{\ ·}^{-}}}$)及过氧化氢(H2O2)的产生,同时降低脂氧合酶的活性,保持较低的饱和脂肪酸含量、较高的不饱和脂肪酸含量和膜脂不饱和度。综上,热处理可维持黄瓜果实活性氧代谢的平衡,抑制膜脂的过氧化作用,从而提高黄瓜果实的抗冷性,减轻果实冷害损伤。  相似文献   
14.
李佩艳  尹飞  党东阳  甘瑞卿  李鑫玲  梁华 《核农学报》2020,34(12):2742-2748
为探讨草酸处理对低温冷藏下芒果冷害及细胞壁代谢的影响,本试验以桂七芒果果实为试材,采用5 mmol·L-1草酸溶液浸泡处理,以清水浸泡处理为对照,并于4℃贮藏,分析芒果的冷害指数、丙二醛(MDA)含量、相对电导率、硬度、细胞壁物质含量、细胞壁代谢酶的变化。结果表明,与对照组相比,草酸处理显著降低了低温贮藏14 d后桂七芒果果实冷害指数、MDA含量、相对电导率、原果胶和纤维素含量,显著降低了低温贮藏28 d后果实的硬度;显著提高了低温贮藏14 d后果实水溶性果胶含量及多聚半乳糖醛酸酶(PG)、果胶甲酯酶(PME)、纤维素酶(Cx)活性,显著提高了贮藏21 d后果实β-半乳糖苷酶(β-Gal)活性。综上所述,草酸处理能减轻桂七芒果冷害,维持采后果实细胞壁降解酶较高活性和水溶性果胶含量。本研究为揭示草酸减轻芒果果实冷害机制提供了依据,可为草酸应用于其他冷敏型果实的贮藏保鲜提供理论参考。  相似文献   
15.
AIM: To investigate the effect of all-trans retinoic acid (ATRA) on blood-brain barrier after cerebral ischemia-reperfusion (CIR) injury in rats and its possible role mechanism.METHODS: Male SD rats were randomly divided into sham group, model (CIR) group and CIR+ATRA (10, 30 and 90 mg/kg) groups. The rat model of CIR injury was established by MCAO thread occlusion method. After ischemia for 1.5 h and reperfusion for 24 h, the neurological functional behavioral score, cerebral infarction volume, brain water content and Evans blue content were determined. The activity of matrix metalloprotein-9 (MMP-9) was measured by gelatin zymography. The protein levels of claudin-5, occludin, ZO-1, JNK, p-JNK, P38, p-P38 and MMP-9 in the brain tissues were determined by Western blot.RESULTS: Compared with CIR model group, ATRA at 30 mg/kg significantly improved neurological function, and decreased cerebral infarction volume, brain water content, Evans blue content and the degradation of tight junction proteins in ischemic area (P<0.01). The activity and protein expression of MMP-9 in ischemic brain tissue were decreased (P<0.01). The phosphorylation of JNK and P38 was inhibited and the protein levels of p-JNK and p-P38 were decreased (P<0.01).CONCLUSION: ATRA reduces the damage of brain tissue and the destruction of blood-brain barrier induced by CIR in rats. The protective effect may be related to inhibiting the activation of JNK/P38 MAPK signaling pathway and MMP-9.  相似文献   
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AIM: To investigate the expression and function of circular RNA_0000231 (circ_0000231) in non-small-cell lung cancer (NSCLC). METHODS: RT-qPCR was used to detect the expression of circ_0000231 in the NSCLC tissues and cell lines. circ_0000231 small interfering RNA (si-circ_0000231) or negative control siRNA of circ_0000231 (NC) was transfected into the NSCLC cells. The proliferation and apoptosis of the NSCLC cells were detected by CCK-8 assay, colony formation assay and flow cytometry, respectively. The expression of cyclin D1 (CCND1) and anti-apoptotic protein Bcl-2 were determined by RT-qPCR and Western blot. RESULTS: The expression of circ_0000231 in the NSCLC tissues and cell lines was significantly up-regulated compared with precancerous tissues and lung epithelial cells BEAS-2B (P<0.05). After transfection of NSCLC cells with si-circ_0000231, the cell viability, colony formation numbers were significantly decreased, and the apoptotic rate in si-circ_0000231 group was significantly increased as compared with NC group (P<0.01). In addition, the results of RT-qPCR and Western blot showed that transfection of si-circ_0000231 inhibited the expression of CCND1 and Bcl-2 (P<0.01). CONCLUSION: The expression of circ_0000231 is significantly increased in the NSCLC tissues and cells. Knock-down of circ_0000231 expression significantly inhibits the proliferation of NSCLC cells.  相似文献   
18.
Myoblast differentiation is an essential process during skeletal muscle development. C2 C12 myoblast is a commonly used experimental model to study muscle cell differentiation in vitro. Dehydrogenase/reductase(SDR family) member 3(DHRS3) is a highly conserved member in short-chain alcohol dehydrogenase/reductase superfamily and has been shown to be involved in the metabolism of retinol. Previous experimental results showed that the expression of DHRS3 increased significantly during the differentiation of myoblasts differentiation. However, the effect of DHRS3 on mouse muscle cell differentiation was unclear. The objective of current study was to determine if DHRS3 affected muscle cell differentiation, and if DHRS3 was involved in muscle regeneration. Protein expression was determined by western blot and immunofluorescence analysis. The activation and inhibition of DHRS3 increased and decreased C2 C12 myoblast differentiation respectively, which indicated that DHRS3 could affect C2 C12 myoblast differentiation. DHRS3 expression was significantly changed during muscle regeneration, with the regeneration of muscle injury, the expression of DHRS3 tended to increase first and then decrease. It suggested that DHRS3 might be involved in muscle regeneration. In summary, this study confirmed the involvement of DHRS3 in C2 C12 myoblast differentiation and mouse skeletal muscle regeneration and provided a theoretical basis for further elucidating the molecular mechanism of muscle development.  相似文献   
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小麦生长发育受冻害影响,而不良的环境条件严重危害小麦成长。冻害主要是指因温差骤降且时间过长影响小麦成长的情况。漯河地区冬季小麦冻害情况极为严重,而二类、三类麦田屡见不鲜,冬季冻害会造成极为严重的经济损失,只有针对其实际情况进行深入分析,并采取有效举措予以应对,即能够保证漯河地区小麦的稳定产量。  相似文献   
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