Effect of miR-29b-mediated TGF-β/Smad signaling pathway on progression of hepatic fibrosis in rats

AIM: To investigate the role of microRNA-29b (miR-29b)-mediated TGF-β/Smad signaling pathway in the activation of hepatic stellate cells (HSC) and its effect on the progression of hepatic fibrosis in rats.METHODS: Hepatic liver fibrosis rat model was established, and its HSC were isolated. Normal rat HSC were also obtained and identified in vitro. RT-qPCR and Western blot were used to detect the alterations of miR-29b, TGF-β/Smad signaling pathway-related proteins and liver fibrosis marker proteins in the acquired cells. Finally, the direct targeting binding of miR-29b to TGF-β1 was identified by dual-luciferase reporter assay system.RESULTS: With the activation of HSC, the expression of miR-29b gradually decreased (P<0.01), while the expression of collagen type I and α-smooth muscle actin gradually increased (P<0.01). At the same time, the expression of Smad2/3/4 was significantly increased, and the expression of Smad7 was significantly decreased (P<0.01). Dual-luciferase reporter assay showed that miR-29b bound directly to "UCUCUCCGU" in the 3'UTR of TGF-β1, indicating that TGF-β1 was a downstream target gene of miR-29b.CONCLUSION: miR-29b may be involved in the inhibition of HSC activation and migration, thereby inhibiting the process of liver fibrosis. The biological function of miR-29b may be through the direct targeting of TGF-β1, thus regulating and inhibiting the TGF-β/Smad signaling pathway.     

基于蛋白质组学研究光质对番茄果实挥发性物质的影响机理

以‘Micro-Tom’番茄(Solanum lycopersicum L.)为试材,种子发芽后30d移入人工气候室,分别进行红/蓝光组合(1:1、3:1、5:1、7:1)处理,以白光处理为对照。在番茄果实绿熟期、转色期、成熟期取样,测定果实挥发性物质含量及蛋白组数据。结果表明,在转色期和成熟期,对番茄风味有积极作用的己醛、反式–2–己烯醛、β–紫罗兰酮、牻牛儿丙酮、6–甲基–5–庚烯–2–酮、2–苯乙醇、愈伤木酚的含量在红/蓝光3︰1组合处理中最高,而对风味有消极作用的水杨酸甲酯的含量较低,并且在成熟期为0。进一步分析了红/蓝光3︰1组合处理与对照相比的差异蛋白,在成熟过程中番茄果实共鉴定到12个与挥发性物质产生有关的差异蛋白,其中8个上调表达,4个下调表达。通过对12个差异蛋白进行mRNA水平的验证发现,只有转色期的苯丙酮酸互变异构酶(MIF)在蛋白质和mRNA水平表达不一致,其他11个蛋白在两个水平表达均一致。     

豫北山区“粮—草—羊”高效平衡养羊模式现状

从粮食作物、经济作物及饲草的种植,饲草料的加工调制与利用,全舍饲肉羊的养殖及杂交繁育,以及羊粪尿的资源化利用等方面介绍了豫北山区“粮—草—羊”高效平衡养羊模式发展现状,以期为促进豫北山区资源可持续利用、山区生态环境良性循环和社会经济可持续发展提供思路。     

根域限制栽培对主干形‘圆梦’桃生长和果实品质的影响

根域限制栽培具有控制树冠、促进果树成花的优点，适宜在主干形整枝的密植果园中应用，但不同品种桃表现不同。‘圆梦’桃是由‘湖景蜜露’和‘白丽’杂交而来的中晚熟新品种，为明确‘圆梦’用作南方密植品种的适用性，以浙江省桃主栽品种‘湖景蜜露’为对照品种，对其营养生长、成花量和果实品质进行了研究，结果表明根域限制栽培的‘圆梦’树体营养生长和枝条成花量与‘湖景蜜露’基本一致，且果型大小、糖度、色泽更优。     

6种梨果实对轮纹病的抗性差异及4种杀菌剂对轮纹病菌的抑菌作用

由葡萄座腔菌Botryosphaeria dothidea引起的梨轮纹病是梨生产中重要的真菌性病害,主要造成树势早衰和果实腐烂,严重影响梨的产量和品质。本研究选取市售的6个品种的梨果实,用分离自梨枝干的轮纹病菌进行了离体果实接种,测定不同品种果实对梨轮纹病的抗性差异。接种后6 d,按照病斑直径从大到小的顺序,品种排序依次为‘丰水梨’‘南果梨’‘库尔勒香梨’‘皇冠梨’‘雪花梨’‘砀山酥梨’,随病斑减小抗性依次增强。测定了4种杀菌剂对梨轮纹病菌菌丝生长的抑制作用,结果表明,咯菌腈、氟啶胺和咪鲜胺对梨轮纹病菌的菌丝生长有很强的抑制作用,EC_(50)分别为0.010 3、0.022 4μg/mL和0.034 3μg/mL;代森锰锌的EC_(50)为3.860 7μg/mL,也有较好的抑菌效果。本试验结果为了解不同梨品种对轮纹病的抗性及杀菌剂的选用提供了依据,具有一定的指导意义。     

富锗酵母培养物对下笼蛋鸡肉品质、肠道菌群及结构的影响

本试验旨在研究富锗酵母培养物对下笼蛋鸡肉品质及肠道的影响。选取505日龄健康的海兰褐壳蛋鸡480只,随机分为4组,每组5个重复,每个重复24只鸡。对照组饲喂基础日粮,试验组在基础日粮中分别添加12、16、20 mg/kg的富锗酵母菌培养物。预试期7 d,正试期为42 d。结果表明:与对照组相比,12、16、20 mg/kg组腿肉的蒸煮损失分别降低45.2%、33.6%、39.7%(P<0.01),pH均高于对照组(P<0.01);16mg/kg组腿肌的亮度(L~*)低于对照组(P<0.05);12、16、20 mg/kg组腿肌的剪切力分别比对照组低44.13%、56.07%、50.60%(P<0.01);各试验组胸肌pH均高于对照组(P<0.01),16mg/kg组的pH高于12、20mg/kg组(P<0.05);与对照组相比,16mg/kg组乳酸菌数量升高(P<0.05);空肠中,各试验组的绒毛长度高于对照组(P<0.01);16、20 mg/kg组绒毛长度/隐窝深度高于对照组(P<0.01)。结果显示,日粮中添加富锗酵母培养物可以改善下笼蛋鸡小肠的形态结构和肠道菌群平衡,提高鸡肉品质,建议添加量为16 mg/kg。     

PPARγ mediates effects of diosgenin on proliferation and apoptosis in human glioblastoma U87MG cells

AIM:To investigate the effect of diosgenin (Dio) on the proliferation, apoptosis and expression of peroxisome proliferator-activated receptor γ (PPARγ) in human glioblastoma U87MG cells and its possible mechanism. METHODS:Human astrocytes (HA) and U87MG cells were cultured in vitro and treated with Dio (0, 10, 20, 30, 40 and 50 μmol/L) and GW9662 (5 μmol/L) for 48 h, and then the cell viability was detected by CCK-8 assay. Cell colony formation assay was used to assess the proliferation potential. Flow cytometry was used to analyze the cell cycle distribution and apoptosis. The mRNA expression level of PPARγ was measured by RT-PCR. Western blot was used to determine the protein levels of PPARγ, cyclin D1, cyclin E1, Bcl-2 and Bax. RESULTS:Dio had no significant influence on the viabi-lity of HA (P>0.05). However, Dio remarkably reduced the viability of U87MG cells in a dose-dependent manner (P<0.05) with IC₅₀ of 24.31 μmol/L. Meanwhile, Dio remarkably diminished colony formation ability (P<0.05), induced G₀/G₁ phase arrest of the cell cycle and apoptosis (P<0.05), up-regulated the expression of PPARγ at mRNA and protein levels, increased the protein level of Bax (P<0.05), and down-regulated the protein levels of cyclin D1, cyclin E1 and Bcl-2 (P<0.05) in a dose-dependent manner. However, these effects induced by Dio were inhibited by GW9662 (P<0.05), a specific inhibitor of PPARγ. CONCLUSION:Dio may inhibit proliferation and induce apoptosis in human glioblastoma U87MG cells most likely via up-regulating the expression of PPARγ, and then down-regulating the protein levels of cyclin D1, cyclin E1 and Bcl-2, and up-regulating the protein level of Bax.     

伐地那非增加EGCG-β-乳球蛋白纳米粒对肝癌细胞的抑制作用

较高浓度的EGCG才能抑制癌细胞的增殖,通过纳米化和EGCG与其他药物的联合使用是提高EGCG生物活性的重要策略。本研究将EGCG和伐地那非（VD）同时包埋于β-乳球蛋白（β-Lg）纳米载体中,制备出EGCG-VD-β-Lg纳米粒（EVβ-NPs）,体外试验证实,EVβ-NPs能提高人肝癌细胞（HepG2细胞）中Caspase-3活性,使HepG2细胞在S期产生明显的阻滞,诱发细胞核分裂,从而导致HepG2细胞凋亡。研究结果表明,将EGCG与微量的VD联合使用,并通过纳米化包埋可以显著提高EGCG的抗癌活性。这一方法在EGCG抗癌制品的开发方面具有潜在的价值。     

滴灌施肥对幼龄茶树生长和养分吸收的影响

通过田间试验,研究了龙井43、白叶1号品种茶园滴灌施肥对幼龄茶树生长、养分吸收、品质成分等的影响,分析了不同施肥模式下的施肥成本投入情况。结果表明,与常规开沟施肥相比,采用滴灌施肥后,即使在化肥减量25%的情况下,树高、主干直径、树幅都显著增加,修剪物生物量增加明显;茶树对养分的吸收量明显增加,而养分的渗漏损失明显减少,从而提高了养分利用效率。从滴灌施肥的次数上分析,龙井43品种,在试验条件下年施肥次数7次可以达到较好效果,而白叶1号品种,年施14次的效果较好。