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81.
Oxidative stress can induce apoptosis of granulosa cells and lead to follicular atresia, thereby reducing the number of pigs giving birth. The aim of this study was to investigate the protective effect of Periplaneta americana peptide (PAP) on the apoptosis of the granulosa cells of pig ovaries (PGCs) induced by hydrogen peroxide (H2O2) via FoxO1. PGCs were treated with H2O2 to establish a cell apoptosis model. Cell viability was measured using the cell counting kit-8 (CCK-8) assay, and cell apoptosis was detected using flow cytometry. The malondialdehyde (MDA) level and nitric oxide (NO) content were detected to reflect the oxidative stress. Western blotting, qRT-PCR and overexpression were undertaken to determine the expression of FoxO1 and caspase-3, and immunofluorescence was used to detect FoxO1 in the nucleus and cytoplasm. PGCs were treated with 100 μM H2O2 for 6 hr, which resulted in oxidative damage and apoptosis and an apoptosis rate for PGCs of 32.95%. Next, PGCs were treated with 400 μg/ml PAP for 24 hr to repair the apoptosis induced by H2O2. PAP improved cell viability in H2O2-stimulated PGCs, the increased MDA level and NO content caused by H2O2 stimulation were reversed and the apoptotic rate of PGCs was reduced. The qRT-PCR and Western blotting results indicated that PAP decreased the H2O2-induced apoptosis and the expression of FoxO1 and caspase-3 in PGCs. The effect of PAP was the same following FoxO1 overexpression. FoxO1 was expressed in the nucleus when stimulated by H2O2 or overexpression; however, it migrated to the cytoplasm following PAP treatment. PAP decreased the apoptosis of PGCs induced by H2O2 by regulating FoxO1 expression and nuclear translocation.  相似文献   
82.
AIM To investigate the role of monocyte chemoattractant protein-1 (MCP-1) and its receptor CC chemokine receptor 2 (CCR2) in ethanol-promoted breast cancer angiogenesis and the underlying mechanism. METH?ODS: A mouse model of transplanted breast tumor with moderate alcohol consumption was established. The correlations between the expression of MCP-1/CCR2 and the expression of angiogenesis markers [platelet endothelial cell adhesion molecule-1 (PECAM-1) and vascular endothelial growth factor (VEGF)] in tumor tissues were examined by immunohistochemistry. In vitro, a 3D tumor-endothelial co-culture system was established to observe tumor angiogenesis and the role of MCP-1/CCR2 signaling pathway in alcohol-mediated angiogenesis. The cell migration ability was detected to clarify whether MCP-1/CCR2 enhanced cell mobility to form new vessels. RESULTS MCP-1 and CCR2 were both highly expressed in the breast tumor tissues of tumor-bearing mice consuming alcohol, and their expression levels were consistent with the angiogenic markers PECAM-1 and VEGF (P<0.05). The interaction between mouse breast cancer E0771 cells and endothelial cells was observed to promote angiogenesis in the 3D tumor-endothelial co-culture system with or without alcohol stimulation. MCP-1 promoted this kind of tumor angiogenesis, while CCR2 antagonist effectively inhibited the tumor angiogenesis and especially blocked alcohol-induced angiogenesis. Activation of MCP-1/CCR2 signaling pathway enhanced the migration ability of endothelial cells. CONCLUSION The MCP-1/CCR2 signaling pathway plays an important role in promoting the angiogenesis of breast cancer stimulated by alcohol. The mechanism might be that MCP-1 improves the migration of endothelial cells and then promotes angiogenesis.  相似文献   
83.
AIM To study the effect of microRNA-153-3p (miR-153-3p) knock-down on oxidative injury of H9C2 cells induced by H2O2 and its specific mechanism. METHODS The oxidative stress injury of H9C2 cell model was induced by H2O2, and then the cell viability and the expression of miR-153-3p were detected by MTT assay and RT-qPCR, respectively. The effects of miR-153-3p knock-down on the H9C2 cell injury under oxidative stress were studied by RNA interference technology. The targets of miR-153-3p were identified by Western blot and dual-luciferase reporter assay. RESULTS MTT assay showed that the viability of H9C2 cells was decreased with the increase in H2O2 concentration (P<0.05). The results of RT-qPCR showed that the expression of miR-153-3p was increased with the increase in H2O2 concentration (P<0.05). Knock-down of miR-153-3p increased the viability of H9C2 cells under oxidative stress, decreased the cell apoptosis and the content of malondialdehyde (MDA), and increased the activity of superoxide dismutase (SOD). The expression of nuclear factor E2-related factor 2(Nrf2) and antioxidant response element(ARE) activity were increased with the increase in H2O2 concentration (P<0.01). TargetScan analysis and dual-luciferase reporter assay showed that Nrf2 was one of the potential target genes of miR-153-3p. The results of Western blot further showed that over-expression of miR-153-3p inhibited the expression of Nrf2 (P<0.01), while down-regulation of miR-153-3p increased the expression of Nrf2 (P<0.01). Dual interference with Nrf2 and miR-153-3p significantly reduced H9C2 cell viability, promoted the apoptosis, increased MDA content, and decreased SOD activity in the presence of H2O2 (P<0.01). CONCLUSION Inhibition of miR-153-3p expression attenuates the injury of H9C2 cells induced by H2O2 through up-regulating Nrf2/ARE signaling pathway.  相似文献   
84.
【目的】探讨不同灌水下限设施土壤CO2排放特征及其影响因素,为调控设施土壤水分和碳排放提供理论依据。【方法】在番茄生育期内采用LI-8100A土壤碳通量自动测定仪观测不同灌水下限[20 kPa(D20)、30 kPa(D30)、40 kPa(D40)]下的土壤CO2排放速率,并分析其影响因素。【结果】在番茄生育期内,不同灌水下限设施土壤CO2排放速率变化趋势基本一致,D20处理最高,平均速率为2.759μmol/(m2·s),其次是D30处理,为2.601μmol/(m2·s),D40处理最低,为2.559μmol/(m2·s)。在土壤CO2累积排放量方面,D20处理显著高于其他2个处理,而D30和D40处理之间无显著差异。就单因素模型而言,不同灌水下限处理的土壤CO2排放速率与15 cm土壤温度呈指数回归关系,且均达显著水平(P<0.05);不同灌水下限处理的土壤CO2排放速率与15 cm土壤含水率均呈显著二次回归关系(P<0.05);与单因素模型相比,土壤温度和土壤含水率的双因素复合模型(68.5%~83.8%)可以更好地解释土壤CO2排放的变化。土壤温度敏感系数Q10值在1.442~1.498之间,其中D20处理最敏感,D40处理最不敏感。相关分析结果表明,土壤CO2累积排放量与0~20 cm土层土壤有机质量、pH值、全氮量、速效磷量、速效钾量、碱解氮量和微生物量碳呈显著相关关系。采用PCA分析提取出的2个主成分累积贡献率为85.79%。【结论】灌水下限影响设施土壤CO2的排放,其中D20处理促进了设施土壤CO2的排放。  相似文献   
85.
【目的】近年来,硅对于的植物影响受到人们广泛关注,人们试图将硅确定为植物生长发育的的“必要元素”。因此如何提高植物对硅的吸收利用来增加植物的农艺性状和产量,是当前农业和林业研究的一个重要课题。【方法】以黄枝杉Cunninghamia lanceolata和罗田垂枝杉C.lanceolata var.luotian为材料,采用盆栽的方式,研究施加不同浓度的纳米SiO2颗粒(0、1、2、4 g/盆)对杉木幼苗光合参数、叶绿素荧光、叶片厚度、氮磷钾含量及其分配、生物量累积的影响。【结果】本研究结果显示,SiO2纳米颗粒对杉木根系的生长发育有很大的促进作用,使之能更好的吸收养分,加强了氮磷钾含量的累积。且叶片的厚度也有所增加,在较低的浓度下,气孔导度、光合作用机制、以及光合作用效率增加;地上的生物量也随着施入SiO2纳米颗粒浓度的增加而增加。【结论】我们的实验表明,SiO2纳米颗粒通过促进根系发育加强对营养的吸收和提升叶片厚度,以及提高净光合速率和气孔导度来提高植物的生长机理,进而增加植物的生物量来提升产量。鉴于其对植物生长发育及产量的多种积极影响,硅纳米材料将会为农林植物增产有重要的影响和广阔的前景。  相似文献   
86.
试验旨在研究3种转染方法对猪肾上皮细胞(PK15)的转染效率,为以PK15细胞为模型研究外源基因的功能提供参考。本研究以PK15细胞为研究对象,用脂质体、电穿孔、慢病毒3种转染方法转染后,在荧光显微镜下观察绿色荧光蛋白的表达,采用实时荧光定量PCR检测EGFPNR2F2基因的表达情况,采用CCK-8检测细胞存活率,进而比较3种方法的转染效果。结果显示,转染PK15细胞后,电穿孔和慢病毒方法转染效率极显著高于脂质体(P<0.01),但电穿孔方法和慢病毒方法之间差异不显著(P>0.05);EGFPNR2F2基因的实时荧光定量PCR结果显示慢病毒方法效果最好,脂质体方法较差,与细胞转染效率基本一致;CCK-8结果显示,电穿孔转染后细胞存活率最低,极显著低于对照组(P<0.01),脂质体方法显著低于对照组(P<0.05),慢病毒方法与对照组间差异不显著(P>0.05)。综合考虑转染效率及细胞活性,本研究认为慢病毒转染方法最适合转染PK15细胞,为今后高效转染PK15细胞提供了理想的方法。  相似文献   
87.
胰岛素样生长因子2(insulin-like growth factor 2,IGF2)作为胰岛素类激素家族中重要成员之一,广泛参与机体众多生理代谢过程,在癌症发生、神经调节、糖代谢疾病、骨质疏松、肌肉发育和脂肪沉积等方面具有重要的作用,其功能行使主要通过与受体IGF1R和IGF2R结合或与胰岛素样生长因子结合蛋白IGFBPs和IGF2BPs竞争性结合发挥功能。鉴于IGF2基因在肌肉发育和脂肪沉积中的重要作用,发掘IGF2基因相关分子标记并解析其内在调控机理,在畜牧生产中具有重要的意义。研究发现,众多IGF2基因遗传变异与动物的生长发育之间存在显著相关关系,其可能通过影响IGF2基因印记、甲基化状态、转录因子结合或miRNA靶向结合型转录后调控等方式发挥作用。因此,文章综述了IGF2基因表达调控模式,包括IGF2与其受体的调控关系,基因印记与miRNA参与的表观遗传调控,转录因子对其的调节作用,遗传变异等方面的内容,以期为IGF2基因在动物生长发育调控相关研究中提供相应的借鉴,为分子育种提供有效线索。  相似文献   
88.
The present study investigated the effects of elevated carbon dioxide concentration ([CO2]) and air temperature on the germination of seed bulbils and the seedling vigour of two Chinese yam lines. Plants were grown under two [CO2] levels, ambient and elevated (ambient + 200 μmol mol?1), and two mean air temperature regimes, 22.2 °C (ambient + 1.4 °C) and 25.6 °C (ambient + 5.2 °C). Elevated [CO2] did not affect bulbil germination under both air temperature regimes. During the early growth stage, the dry weight (DW) of leaves, vines, shoots, roots, belowground parts (roots + tubers) and whole plants were higher under elevated [CO2] than ambient [CO2] for both lines under the low- and high-temperature regimes. The values of vigour indexes (index I = germination % × seedling length and index II = germination % × seedling DW) were also higher under elevated [CO2] than ambient [CO2] for both lines. These results indicated that Chinese yam seedlings respond positively to elevated [CO2] during the early growth stage. The above:belowground DW ratios were lower under elevated [CO2] than ambient [CO2] in seedlings with very small new tubers for both yam lines, indicating that elevated [CO2] strongly affected the root growth in the early growth stage. The DWs of post-treatment seed bulbils were higher in the elevated [CO2] under both air temperature regimes. The results showed that Chinese yam used a smaller amount of the reserves in seed bulbils under elevated [CO2] than under ambient [CO2].  相似文献   
89.
The purpose of the research was to identify the phenolic and flavonoid compounds of seven different traditional pigmented whole rice cultivars grown in the temperate regions of Kashmir so as to study their relationship with in vitro antioxidant capacities. The completely pigmented rice cultivars were found to have higher phenolic, flavonoid, anthocyanin contents and exhibited higher antioxidant capacities than the light colored and sparely colored rice cultivars. A total of 40 compounds had been identified in the analyzed rice cultivars that were found to be distributed in 6 major categories with 6-phenolics, 6-flavonoids, 11-hydroxycinnamic acid derivatives, 7-hydroxybenzoic acid derivatives, 3-anthocyanins and 7-flavonoid glucosides of different flavonoid compounds. Among the free and bound fractions for each cultivars the light and sparsely colored depicted higher content of phenolics and in vitro antioxidant properties in bound faction, while the completely pigmented cultivars showed higher antioxidant properties in free fractions. The anthocyanins quercetin-3-O-galactoside, cyanidin-3-O-rutinoside and pelargonidin-3-O-diglucoside had been identified by LC-MS existing in the free fractions of the analyzed rice cultivars whereas, the free fraction of acetone + H2O possessed higher percentage of phenolic compounds as compared to methanolic extracts and bound fractions. The black colored cultivars possessed higher DPPH scavenging activity and lipid peroxidation inhibition.  相似文献   
90.
Inheritance of fertility restorer gene in pigeonpea was studied using F2 and BC1F1 populations derived from cross AL103A × IC245273. It was found to be controlled by single dominant gene. Out of 228 SSR primer pairs, 33 primer pairs showed parental polymorphism, while four primers were found polymorphic in bulk segregant analysis (BSA). These four primers viz., CcM 1615, CcM 0710, CcM 0765 and CcM 1522 were used for genotyping of F2 population and were found to be placed at 3.1, 5.1, 28.1 and 45.8 cM, respectively. Two of them, CcM 1615 and CcM 0710, evinced clear and unambiguous bands for fertility restoration in F2 population. The Rf gene was mapped on linkage group 6 between the SSR markers CcM 1615 and CcM 0710 with the distances of 3.1 and 5.1 cM, respectively. The accuracy of the CcM 1615 was validated in 18 restorers and six maintainer lines. The marker CcM 1615 amplified in majority of male restorer lines with a selection accuracy of 91.66%.  相似文献   
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