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61.
旨在研究山羊β防御素124(goat beta-defensin 124,gBD124)沉默对p38MAPK/AP1通路及下游细胞趋化因子和细胞因子表达的影响。本研究将设计的3条gBD124-shRNAs载入LV10-U6/RFP&Puro质粒载体,与包装质粒共转染到293T细胞中,用梯度稀释法测定病毒原液的滴度;将构建的3个LV10-gBD124和LV10-gBD124-NC载体转染到山羊附睾头细胞中,筛选有效沉默载体;然后用有效沉默载体联合转染附睾头细胞,设置了空白细胞对照组、LV10-NC组、有效沉默载体组,用2 μg·mL-1嘌呤霉素筛选后分别收集细胞和培养液,采用qRT-PCR、Western blot和ELISA检测gBD124、MAPK信号通路关键蛋白、细胞因子及趋化因子基因及蛋白表达情况。本研究构建了gBD124沉默慢病毒载体,筛选出LV10-gBD124-51和LV10-gBD124-161两个有效载体,并成功构建了gBD124沉默稳定转染的附睾头细胞株。与NC对照组相比,gBD124沉默显著降低了山羊附睾头细胞MAPK通路中MAPK1以及AP1的两个亚型c-JUNc-FOS基因表达(P<0.05),显著增加了RASA1基因表达(P<0.05);gBD124沉默显著降低了总p38MAPK、总c-JUN和总c-FOS蛋白表达,以及磷酸化p38MAPK和c-JUN蛋白表达(P<0.05);gBD124沉默显著上调了MAPK通路下游IL-1β及其受体IL-1R2、IL-8和趋化因子CCL6和CCL21基因表达(P<0.05),下调了CCL5和IL-1α基因表达(P<0.05);gBD124沉默显著降低了细胞培养液中CCL5浓度(P<0.05)。与空白对照组相比,gBD124沉默显著增加了培养液中IL-1β和IL-8浓度,降低了IL-1α浓度(P<0.05)。gBD124基因沉默通过抑制p38MAPK/AP1信号通路调控附睾头细胞趋化因子和细胞因子的表达。  相似文献   
62.
应用EM38电磁感应电导仪测量法调查了罗布泊“耳纹”地区盐壳电导值,对干盐湖沉积物采取不同尺度和不同空间分辨率的取样与测量。研究结果表明,盐壳土壤EM38电导的各特征参数值均表现出明显的空间变异性,“耳纹”的形成和电磁感应电导所表征的物理量存在较好相关性:“耳纹”黑色区域电导值较高,白色区域电导值较低。  相似文献   
63.
为了对防治黄瓜疫病的生防菌株LY-38的产业化生产提供参考,通过单因子试验和正交试验,对培养基组分中最佳碳源、氮源和无机盐进行筛选,在确定适合该菌株的培养基组分基础上,对其培养条件进行优化。结果表明:适合枯草芽孢杆菌生防菌株LY-38拮抗物质产生的最佳碳源为葡萄糖和玉米淀粉,最佳氮源为蛋白胨和黄豆粉,含量为葡萄糖1.0%、玉米淀粉0.5%、蛋白胨1.0%和黄豆粉2.0%;最佳无机盐为MgSO4·7H2O和CaCO3;最佳培养温度为32℃、培养时间为44h、初始pH 7.2、接种量为3.0%(体积分数)、转速为150r/min。在优化后的培养基成分和培养条件下,LY-38菌株发酵滤液的拮抗圈直径可达21.2mm,比基础培养基的拮抗圈直径提高41.3%。  相似文献   
64.
Feng AW  Yu C  Mao Q  Li N  Li QR  Li JS 《Fitoterapia》2011,82(7):976-982
The effect of berberine hydrochloride (BBR) on inducible cyclooxygenase-2 (COX-2) in small intestinal mucosa and related mechanisms was investigated in a rat model of acute endotoxemia. The results showed that lipopolysaccharide (LPS) increased COX-2 expression, whereas SB202190 and BBR curtailed it. LPS increased phosphorylation of mucosal p38 MAPK and ATF2 as well as production of ATF2, whereas BBR attenuated these effects. LPS upregulated mucosal peroxisome proliferator-activated receptor gamma (PPARγ), but BBR reduced this receptor. GW9662 aggravated LPS-induced and reversed BBR-attenuated COX-2 expression. The findings showed that BBR ameliorated COX-2 overexpression partially via modulation of p38 and PPARγ pathways during acute endotoxemia.  相似文献   
65.
M. Gowda    S. Roy-Barman    B. B. Chattoo 《Plant Breeding》2006,125(6):596-599
Blast, caused by Magnaporthe grisea, is the most devastating disease of rice worldwide. In this study, the main objective was to identify and map a new gene for blast resistance, in an indica rice cultivar ‘Tadukan’ against blast fungal isolate B157, using molecular tools. F2 segregating population was derived from ‘CO39’ (susceptible) and ‘Tadukan’ (resistant), and molecular mapping of the blast resistance gene was carried out using simple sequence length polymorphism (SSLP) and amplified fragment length polymorphism (AFLP) methods. Two SSLP markers, RM206 and RM21 and three AFLP markers (AF1: E‐aca/M‐ctt; AF2: E‐aca/M‐cat and AF3: E‐acc/M‐cac2) were identified to be linked to the resistance gene. The co‐segregation analysis using SSLP markers implied that the blast resistance gene designated Pi38 resides on rice chromosome 11.  相似文献   
66.
This study was conducted to construct zinc finger and BTB domain containing 38 (Zbtb38) gene lentiviral overexpression plasmid vector.Firstly,the CDS sequence of mouse Zbtb38 gene was amplified by overlap extension PCR method using mouse spinal cord tissue,and the Zbtb38 CDS sequence front amplification primer 1 and the latter amplification primer 2 were designed respectively.Using the amplification products of the above two primers as template,primer 3 was designed and subjected to fusion PCR amplification,thereby obtaining the full CDS sequence of Zbtb38.Then,the obtained Zbtb38 gene CDS full sequence was ligated to the plasmid pGM-T,and the recombinant plasmid was transferred into E.coli DH5α competent cells,the positive clones were identified and verified by direct PCR and sequencing.Finally,the Zbtb38 CDS sequence was ligated into the lentiviral vector Plvx-puro by XhoⅠ and BamHⅠ double digestion to obtain the shuttle plasmid Plvx-puro-Zbtb38,which was co-transfected with lentiviral packaging plasmids to produce lentiviral particles in 293T cells.The results showed that the primer 1 amplification product contained the first 1-1 794 bp of the Zbtb38 CDS sequence,and the actual sequencing length of the amplified product was 1 772 bp.The primer 2 amplification product contained the 1 762-3 594 bp of the entire sequence of Zbtb38 CDS,and the actual sequencing length of the amplified product was 1 818 bp,indicating that the fragmented amplification target fragment was successfully obtained.The expected fusion products amplified by primer 3 and the PCR amplification products of the colonies both contained the complete sequence of Zbtb38 CDS (3 594 bp),which was compared with the CDS sequence of Zbtb38 gene in NCBI database,and the coincidence rate was 99.99%,indicating that the Zbtb38 CDS sequence was successfully amplified.The Real-time PCR results showed that the virus titer reached 3.25×108 Tu/mL,which met the experimental animal injection standard requirement,indicating that the lentiviral vector was successfully constructed.In summary,the mouse Zbtb38 gene lentiviral overexpression plasmid vector was successfully constructed in this experiment.  相似文献   
67.
大地电导率仪EM38-MK2数据分析与应用拓展研究   总被引:1,自引:0,他引:1  
采用EM38-MK2测量了0.75m位水平和垂直模式下的表观电导率,并分析其差异性.结果表明,垂直模式下平均△E比水平模式下大18 mS/m,且二者线性相关.建立回归模型时,应结合具体数据选择多种模型拟合对比,以确定最优模型,建议0.75m层位数据取(EH0.75+Ev0.75)/2.  相似文献   
68.
TNF-related apoptosis-inducing ligand (TRAIL) is a tumor-selective apoptosis inducer and has been shown to be promising for treating various types of cancers. However, the application of TRAIL is greatly impeded by the resistance of cancer cells to its action. Studies show that overexpression of some critical pro-survival proteins, such as survivin, is responsible for TRAIL resistance. In this study, we found that Aplysin, a brominated compound from marine organisms, was able to restore the sensitivity of cancer cells to TRAIL both in vitro and in vivo. Aplysin was found to enhance the tumor-suppressing capacity of TRAIL on several TRAIL-resistant cancer cell lines. TRAIL-induced apoptosis was also potentiated in A549 and MCF7 cells treated with Aplysin. Survivin downregulation was identified as a mechanism by which Aplysin-mediated TRAIL sensitization of cancer cells. Furthermore, the activation of p38 MAPK was revealed in Aplysin-treated cancer cells, and its inhibitor SB203580 was able to abrogate the promoting effect of Aplysin on the response of cancer cells to TRAIL action, as evidenced by restored survivin expression, elevated cell survival and reduced apoptotic rates. In conclusion, we provided evidence that Aplysin acts as a sensitizer for TRAIL and its effect on p38 MAPK/survivin pathway may partially account for this activity. Considering its low cytotoxicity to normal cells, Aplysin may be a promising agent for cancer treatment in combination with TRAIL.  相似文献   
69.
对起垄覆膜、起垄无膜处理与常规进行对比试验研究,结果表明:起垄覆膜处理水稻株高增加18.4 cm,分蘖起始时间早9 d、最高分蘖时间早7 d、最高分蘖增加47.5株/m2、穗数增加57.4穗/m2、齐穗和成熟早2 d和3 d、穗粒数增加6.15粒,而千粒重降低1 g、最终水稻理论增产102.8 kg/667 m2,实测产量增加26.6 kg/667 m2,增产达4.36%;起垄无膜处理水稻株高降低4.8 cm、收获穗数降低13.3穗/m2,理论产量减少19 kg/667 m2实测产量减少94.4 kg/667 m2,最终常规处理比起垄无膜处理增产14.65%。  相似文献   
70.
Soil electrical conductivity (ECa) measured by electromagnetic induction (EM) using the EM-38 has shown promise as a soil survey tool. Soil temperature influences ECa readings, and temperature can fluctuate considerably in the upper 10cm of the soil during a day. ECa readings were taken in the horizontal and vertical dipole orientations once an hour from 8a.m. to 8p.m. at four sites on three separate days to determine if ECa values were influenced by diurnal temperature variations. Soil temperature readings were taken at the same times at four depths. EM-38 readings remained steady at all four sites all 3days. Linear regression analysis when temperature in the upper 10cm was plotted against ECa yielded low r 2 values and slopes, indicating no correlation between soil temperature in the upper 10cm and ECa values. Diurnal changes in soil temperature do not significantly influence soil ECa readings obtained with the EM-38 under the conditions encountered during the study.  相似文献   
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