不同春玉米品种茎秆显微结构对抗折强度的响应

以冀西北寒旱区9个春玉米品种为研究对象,通过测定玉米基部第3节抗折强度,利用光学显微镜观察其茎节显微结构,对维管束各项显微指标与节折强度进行相关分析,研究春玉米节折强度与茎秆显微结构之间的关系。结果表明,不同春玉米品种间节折强度达显著水平。对各品种维管束显微指标进行统计分析表明,维管束鞘厚度和表皮细胞厚度变异系数最大,分别达到34.8%和23.2%;茎节维管束数目增多不利于节折强度的提高(r=-0.945**,r=-0.927**),维管束平均面积、韧皮部面积增大有利于节折强度的增加(r=0.831*,r=0.799*;r=0.733*,r=0.786*)。通径分析表明,维管束数目对节折强度的直接效应最大,表皮细胞厚度次之,维管束最大面积、维管束鞘厚度、韧皮部面积等指标也通过维管束数目对茎折强度起间接作用。参试品种中,京农科728、纪元108维管束数目较少,维管束平均面积、韧皮部面积较大,茎折强度较高,抗倒伏性优于其他品种。     

比利时野猪非洲猪瘟防控

2018年9月,比利时公共健康研究院(国家非洲猪瘟参考实验室)确认在瓦隆地区发现野猪感染非洲猪瘟病毒,毒株与2007年欧洲首例非洲猪瘟病毒株非常相似。欧盟和比利时通过采取卓有成效的控制措施,截至目前未发生家猪感染病例。主要防控经验:一是出台法规,组建非洲猪瘟政策委员会,及时评估和措施调整;二是根据OIE的原则要求建立管控区,借助人工屏障和自然屏障,防止感染野猪跨区域移动;三是完善养殖企业生物安全管理制度,防止野猪和家猪的接触,并通过SANITEL系统对境内的所有家猪开展标识追溯,防止高风险地区家猪的非法移动;四是做好宣传,使兽医、养殖户、狩猎者了解非洲猪瘟相关认知,确保防控义务落实到人。     

Distribution of water-stable aggregates under soil tillage practices in a black soil hillslope cropland in Northeast China

Journal of Soils and Sediments - Soil aggregates are the basic units of soil structure. Water-stable aggregates (WSAs) are greatly influenced by tillage practices. The main objective of our study...     

均腐土不同亚纲典型土系土壤细菌群落多样性研究

为研究中国土壤系统分类(CST)体系下均腐土不同亚纲土壤细菌群落结构的多样性，以 4个干润均腐土[富牧西系(DFm)、春雷南系(DCl)、保国系(DBg)、明水系(DMs)]和 4个湿润均腐土[大西江系(MDx)、新发北系(MXf)、卫星农场系(MWx)、裴德系(MPd)]的腐殖质层(Ah层)为研究对象，采用高通量测序技术研究细菌群落多样性，分析细菌群落结构与环境因子间的关系，以探讨影响均腐土不同亚纲群落结构的主要环境因子。结果表明:均腐土 8个土系样品共获得 1 674 634条基因序列，Shannon指数和 Chao1指数表现为:干润均腐土 >湿润均腐土。均腐土 8个土系细菌群落主要包括 10个门类，其中变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、酸杆菌门(Acidobacteria)为富牧西系、春雷南系、保国系、大西江系、新发北系、卫星农场系、裴德系优势菌门，明水系以绿湾菌门(Chloroflexi)、变形菌门(Proteobacteria)、放线菌门(Actinobacteria)为优势菌门；属水平上，均腐土各土系的群落差异较大。样品热图分析将 8个土系细菌群落聚为 2类，其中干润均腐土聚为一类，湿润均腐土聚为一类。pH、交换性 Ca、CEC、交换性 Mg、SOC和 TP是影响均腐土细菌群落结构发生变化的主要因子( P<0.05)。此外，RDA分析发现，土壤 pH为影响均腐土细菌群落结构的主导因子，而 pH、交换性 Ca、CEC为驱动干润均腐土细菌群落结构发生变化的主要影响因素，交换性 Mg、SOC、TP为驱动湿润均腐土细菌群落发生变化的主要影响因素。     

黏虫CYP9A113基因的克隆及外源物质对基因表达的诱导效应

黏虫是我国作物上最重要的害虫之一。细胞色素P450能够参与昆虫外源物质代谢。本研究采用RACE技术克隆了一条编码黏虫P450基因的cDNA序列,并通过Real-time PCR技术,检测了4种外源物质对该基因表达的诱导效应。该基因被国际P450命名委员会命名为CYP9A113,GenBank登录号为KY436739。利用2.5%高效氯氟氰菊酯乳油的LD_(50)处理黏虫3 h,LD_(10)、LD_(30)和LD_(50)处理12 h和24 h,可诱导表达CYP9A113基因;20%氯虫苯甲酰胺悬浮剂的LD_(10)处理黏虫12、24和48 h,LD_(30)和LD_(50)处理24 h,CYP9A113基因表达呈诱导效应;0.1和0.5 mg/mL香豆素处理6、12、24和48 h,CYP9A113基因表达均呈诱导效应;0.1和0.5 mg/mL吲哚-3-甲醇处理3、6、12、24和48 h,CYP9A113基因表达均呈诱导效应。     

NRF2 attenuates oxidative stress and lysosomal dysfunction in doxorubicin-induced H9C2 cells

AIM:To study the effect of nuclear factor E2-related factor 2 (NRF2) on oxidative stress injury and lysosomal dysfunction in doxorubicin (DOX)-induced rat myocardial H9C2 cells. METHODS:The H9C2 cells were treated with DOX. The expression of NRF2 at mRNA and protein levels was determined by real-time PCR and Western blot. The H9C2 cells stably over-expressing NRF2 were established by lentiviral infection. Real-time PCR and Western blot were used to identify the efficiency of over-expression. After DOX treatment, the cell viability was measured by CCK-8 assay, the activity of lactate dehydrogenase (LDH), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), and the content of malondialdehyde (MDA) in the cell supernatant were detected. FITC-dextran was used to analyze lysosomal pH, and the protein expression of lysosomal-associated membrane protein 1 (LAMP1) and cathepsin B was determined by Western blot.RESULTS:The expression of NRF2 at mRNA and protein levels in DOX-treated H9C2 cells was significantly decreased (P<0.05). Over-expression of NRF2 significantly up-regulated the mRNA and protein expression of NRF2 in DOX-treated H9C2 cells (P<0.05). After DOX treatment, the cell viability was decreased, and LDH activity was increased. The activity of SOD, GSH-Px and CAT was decreased, and the content of MDA was increased (P<0.05). The lysosomal pH was increased, and the protein expression of LAMP1 and cathepsin B decreased (P<0.05). Over-expression of NRF2 increased the cell viability, decreased LDH activity, increased the activity of SOD, GSH-Px and CAT, and decreased the content of MDA in cell supernatant (P<0.05). Over-expression of NRF2 also decreased the lysosomal pH, and increased the protein expression of LAMP1 and cathepsin B (P<0.05). CONCLUSION:DOX inhibits the expression of NRF2 in the myocardial H9C2 cells. Over-expression of NRF2 attenuates oxidative stress and lysosomal dysfunction in the H9C2 cells induced by DOX.     

Effects of monocrotaline-induced pulmonary hypertension on expression of Hippo signaling pathway-related molecules in rat lung

AIM:To investigate the expression of Hippo signaling pathway-related molecules in the lung tissues of the rats with pulmonary hypertension induced by monocrotaline for exploring the significance of Hippo signaling pathway in the development of pulmonary hypertension. METHODS:SD rats (n=45) were randomly divided into control group (n=15) and model group (n=30). The rats in model group was given neck subcutaneous injection of monocrota-line at 60 mg/kg to establish pulmonary hypertension model, and the rats in control group was injected with the same volume of normal saline. Four weeks later, right ventricular systolic pressure (RVSP) was measured by right cardiac catheterization, and right ventricular hypertrophy index (RVHI) and right ventricular mass index (RVMI) were calculated. The remodeling of the pulmonary arterioles was observed by HE staining, and medial thickness/external diameter (M/E%) was evaluated. The fibrosis of lung tissues was detected by Masson staining. The protein expression of Yes-associated protein (YAP), tafazzin (TAZ) and TEAD was detected by immunohistochemistry, and the protein and mRNA levels of YAP, TAZ and TEAD in lung tissues were determined by Western blot and RT-qPCR. RESULTS:Compared with control group, the vascular wall in model group was thickened significantly, the M/E% was increased (P<0.01), the pulmonary fibrosis was obvious, and the RVSP and RVHI in model group were significantly higher than those in control group (P<0.01). The immunohistochemical staining showed that the protein expression of YAP, TAZ and TEAD in the pulmonary arterioles in model group was significantly higher than that in control group. The YAP, TAZ and TEAD protein and mRNA levels in the lung tissues were also higher than those in control group (P<0.05). CONCLUSION:The activation of Hippo signaling molecules may promote the remodeling of pulmonary arterioles and further regulate the development of monocrotaline-induced pulmonary hypertension.     

超高效液相色谱—串联质谱法检测鸡血液样品中喹诺酮类药物残留

旨在建立鸡血液样品中多种喹诺酮类药物残留的超高效液相色谱—串联质谱方法。样品经乙腈提取,经Waters Acquity UPLC BEH C₁₈色谱柱分离,以甲醇和0.1%甲酸水溶液为流动相进行梯度洗脱,电喷雾正离子（ESI⁺）模式电离,MRM扫描模式检测。经方法学验证,该方法的线性关系、回收率、精密度均符合要求。应用超高效液相色谱—串联质谱法建立了鸡血液样品中多种喹诺酮类药物同时检测的方法,实现了动物血液样品中12种喹诺酮类药物同时定性、定量分析。     

外源褪黑素和脱落酸对干旱胁迫下葡萄生理特性的影响

为了探讨褪黑素(MT)和脱落酸(ABA)两者混合施用对植物响应干旱胁迫的综合效应,以盆栽‘阳光玫瑰’葡萄为材料,通过根灌100μmol·L~(-1)的MT溶液和叶面喷施50μmol·L~(-1)的ABA溶液及二者组合处理,研究MT和ABA对干旱胁迫下葡萄生理特性的影响。结果表明,与干旱对照组(D_(ck))相比,MT处理导致葡萄叶片MDA、H_2O_2含量和相对电导率分别降低了14.42%、44.11%和21.26%,叶片相对含水量提高了1.12%,同时SOD和POD酶活性分别提高了14.00%和3.01%。这些均表明MT处理有效缓解了干旱胁迫对植株造成的损伤。50μmol·L~(-1 )的ABA处理组叶片MDA含量和相对电导率较干旱对照组提高了9.43%和17.25%,表明ABA处理没有缓解植株的胁迫状态。MT和ABA组合处理具有和MT处理类似的效果。结果表明,褪黑素可以通过减轻膜脂过氧化程度,增强抗氧化系统能力,从而缓解干旱胁迫对葡萄的氧化损伤,提高抗旱性;同时削弱ABA带来的负面效应。