简介:Thereisagrowingsupportforthelowlyingscalarmesonsf0(500),f0(980),a0(980),and(800)tobegenerateddynamicallyfromtheinteractionofpseudoscalarmesons,whilethecaseofthenextsetofscalarresonancesathigherenergies,f0(1370),f0(1710),K0(1430)ismoreaquestionofdebate.Soisthecaseofthetensorresonancesf2(1270),f′2(1525),K2(1430).AnewperspectiveonthesestateshasbeenofferedinRef.[1]wherethef0(1370)andf2(1270)resonancesareshowntobegeneratedfromtheinteractionprovidedbythelocalhiddengaugeLagrangiansimplementingunitarization.Itisshownthattheideaofthenatureofthesestatesasvectormeson-vectormesoncompositestateshasbeentestedinmanyreactions.Yet,thepermanentdiscussionoftheissuedemandsextrachecksforotherobservablesand,inthissense,theweakdecaysbringanewsourceofvaluableinformationthatshouldservetotestdifferentmodels.
简介:目的探索不同f2/f1比值对DPOAEs幅值的影响,寻找最佳的测试参数,以得到最大的DPOAEs测值.方法对12例(24耳)正常青年人进行不同f2/f1比值条件下的DPOAEs幅值测试.结果当f1/f1=1.220时,DPOAEs幅值最大(P<0.05或P<0.01).当f2/f1=1.232时,除了f2=2002Hz处以外,其DPOAEs幅值与f2/f1=1.220时无显著性差异(P>0.05).其他f2/f1值的DPOAEs幅值均较低,多数测值与f2/f1=1.220时相比均有显著性差异(P<0.05或P<0.01).结论f2/f1=1.220~1.232时,DPOAEs测值最大,此范围为最佳测试参数值.
简介:AbstractBackground:Pancreatic stellate cells (PSCs) activation plays a critical role in the development of chronic pancreatitis. Previous studies confirmed that thromboxane A2 receptor (TxA2r) was overexpressed in activated PSCs in rats. The purpose of this study was to investigate the role of TxA2r in the activation of PSCs induced by 8-epi-prostaglandin F2α (8-epi-PGF2α).Methods:TxA2r expression in both quiescent and activated PSCs was detected by immunocytochemistry and immunoblot assay. Isolated PSCs were treated with 8-epi-PGF2α (10-6, 10-7, 10-8 mol/L) for 48 h, and SQ29548 (10-4, 10-6, and 10-7 mol/L), a TxA2r-specific antagonist, for 48 h, respectively, to identify the drug concentration with the best biological effect and the least cytotoxicity. Then isolated PSCs were treated with SQ29548 (10-4 mol/L) for 2 h, followed by 10-7 mol/L 8-epi-PGF2α for 48 h. Real-time polymerase chain reaction was performed to detect the messenger RNA (mRNA) levels of α-smooth muscle actin (α-SMA) and collagen I. Comparisons between the groups were performed using Student’s t test.Results:TxA2r was up-regulated in activated PSCs in vitro compared with quiescent PSCs (all P < 0.001). Compared with the control group, different concentrations of 8-epi-PGF2a significantly increased mRNA levels of α-SMA (10-6 mol/L: 2.23 ± 0.18 vs. 1.00 ± 0.07, t= 10.70, P < 0.001; 10-7 mol/L: 2.91 ± 0.29 vs. 1.01 ± 0.08, t= 10.83, P <0.001; 10-8 mol/L, 1.67 ± 0.07 vs. 1.00 ± 0.08, t= 11.40, P < 0.001) and collagen I (10-6 mol/L: 2.68 ± 0.09 vs. 1.00 ± 0.07, t = 24.94, P < 0.001; 10-7 mol/L: 2.12 ± 0.29 vs. 1.01 ± 0.12, t = 6.08, P < 0.001; 10-8 mol/L: 1.46 ± 0.15 vs. 1.00 ± 0.05, t = 4.93, P = 0.008). However, different concentrations of SQ29548 all significantly reduced the expression of collagen I (10-4 mol/L: 0.55 ± 0.07 vs. 1.00 ± 0.07, t = 10.47, P < 0.001; 10-6 mol/L: 0.56 ± 0.10 vs. 1.00 ± 0.07, t = 6.185, P < 0.001; 10-7 mol/L: 0.27 ± 0.04 vs. 1.00 ± 0.07, t= 15.41, P < 0.001) and α-SMA (10-4 mol/L: 0.06 ± 0.01 vs. 1.00 ± 0.11, t= 15.17, P < 0.001; 10-6 mol/L: 0.28 ± 0.03 vs. 1.00 ± 0.11, t= 11.29, P < 0.001; 10-7 mol/L: 0.14 ± 0.04 vs. 1.00 ± 0.11, t= 12.86, P < 0.001). After being treated with SQ29548 (10-4 mol/L) and then 8-epi-PGF2α (10-7 mol/L), the mRNA levels of a-SMA (0.20 ± 0.08 vs. 1.00 ± 0.00, t= 17.46, P < 0.001) and collagen I (0.69 ± 0.13 vs. 1.00 ± 0.00, t = 4.20, P = 0.014) in PSCs were significantly lower than those of the control group.Conclusions:The results show that 8-epi-PGF2α promoted PSCs activation, while SQ29548 inhibited PSCs activation induced by 8-epi-PGF2α. The result indicated that TxA2r plays an important role during PSC activation and collagen synthesis induced by 8-epi-PGF2αin vitro. This receptor may provide a potential target for more effective antioxidant therapy for pancreatic fibrosis.
简介:摘要本文以一实际工程为例,对超高层剪力墙结构设计计算中的若干关键技术问题进行介绍,如结构选型、结构分析及抗震加强措施等内容。本文有关计算方法可为相关工程设计参考。
简介:摘要:如何保证隧道在富水区穿越断裂带地质条件下的安全施工是隧道施工的关键,本文结合工程实例,针对富水隧道在穿越F2断裂带且岩体为松散角砾岩地质条件下,详细介绍断裂带松散角砾岩隧道超前支护及初期支护措施,主要包含采用超前小导管、超前大管棚、水泥-水玻璃双浆液注浆、初期支护等通过断裂带塌方体的安全施工技术,技术实施后到达预期效果,对类似工程有较高的参考价值。
简介:摘要目的筛选叉头框转录因子F2(FOXF2)作用于结肠癌细胞中Wnt/β-连环蛋白(β-catenin)信号通路的候选靶基因并分析其生物学功能。方法设置干扰FOXF2基因的最佳慢病毒转染获得的HT29细胞为沉默组,空载慢病毒转染获得的HT29细胞为对照组。对照组和沉默组各取三个样本行转录组测序分析;富集到Wnt/β-catenin信号通路,实时荧光定量聚合酶链式反应(RT-qPCR)、蛋白质印迹法(Western blot)验证该通路的候选靶基因。多组间比较采用单因素方差分析,两组间比较采用t检验。结果3组干扰慢病毒沉默HT29细胞中FOXF2的表达效果显著高于空载慢病毒[FOXF2基因信使RNA(mRNA)表达分别为0.29±0.02、0.28±0.05、0.26±0.01比1.00±0.13,FOXF2基因蛋白表达分别为0.20±0.02、0.16±0.01、0.12±0.01比1.00±0.01],差异有统计学意义(F=75.948、3 549.333,均P<0.01),第3组慢病毒沉默FOXF2效果最佳。HT29细胞沉默FOXF2后有389个差异表达基因(DEGs);基因本体论(GO)功能富集分析显示,DEGs显著富集在免疫效应过程、细胞外区域、腺苷酸转移酶活性等功能集团;京都基因与基因组百科全书(KEGG)分析显示,DEGs主要涉及EB病毒感染、NOD样受体信号通路及Wnt信号通路等;Wnt/β-catenin信号通路的候选靶基因骨形成蛋白和激活素的跨膜抑制剂(BAMBI)、富含亮氨酸重复序列的G蛋白耦联受体5(LGR5)、富含亮氨酸重复序列的G蛋白耦联受体6(LGR6)和MSTRG.14182(新基因)主要涉及正向调控Wnt信号通路、细胞增殖和迁移等生物学过程。沉默组中BAMBI、LGR5、LGR6 mRNA和蛋白表达显著高于对照组[mRNA表达分别为1.86±0.21比1.00±0.20、1.95±0.11比1.00±0.09、2.06±0.10比1.00±0.03,蛋白表达分别为1.88±0.02比1.00±0.06、2.08±0.12比1.00±0.04、1.80±0.03比1.00±0.08],差异有统计学意义(t=-5.066、-11.646、-17.584、-24.100、-14.820、-16.710,均P<0.01)。结论沉默FOXF2基因的HT29细胞存在较多的差异表达基因,Wnt/β-catenin信号通路的候选靶基因可能参与正向调控Wnt信号通路、细胞增殖及迁移等生物学过程。