甘氨胆酸对小鼠免疫功能的影响

目的:观察甘氨胆酸(Glycocholic acid,GCA)对正常及免疫抑制小鼠免疫功能的影响。方法:应用环磷酰胺或环孢菌素A所致的免疫抑制模型;采用ELISA及比色法观察了GCA对体液免疫的影响,碳廓清法测定了GCA对单核巨噬细胞的吞噬功能的影响,迟发型皮肤变态反应法观察了GCA对二硝基氯苯丙酮溶液所致小鼠迟发型皮肤过敏反应的影响,并测定了血清中IL-2、TNF-α的含量。采用流式细胞术检测了GCA对小鼠外周血T细胞亚群CD4、CD8比例的影响。结果:GCA能够显著增强正常及抑制小鼠的IgMI、gG的含量;增加外周血中T淋巴细胞CD4比例,使CD4 /CD8 比值提高;显著抑制迟发型皮肤变态反应的发生,并增加IL-2及TNF-α的含量。结论:GCA能够显著提高非特异性免疫功能;显著增强机体的体液免疫能力;显著抑制迟发型变态反应,增强正常及CsA抑制小鼠CD4 百分率、CD4 /CD8 比值,GCA具有调节机体免疫功能的作用。     

0.1%氯吡脲可溶性液剂对西瓜产量和品质的影响

0.1%氯吡脲可溶性液剂50 mg/kg、45 mg/kg、40 mg/kg(毫克/公斤)(有效含量)涂抹西瓜雌花果柄可显著提高西瓜座果率,从而提高西瓜产量,同时在一定程度上可增加西瓜的含糖量和维生素C的含量.     

桃果肉颜色、果皮茸毛和花粉育性性状的分子标记

 以91-42-51 ×瑞光2号的杂交后代共48个单株为试材, 采用集群分离分析法(BSA) , 对桃果实的有毛/无毛、白肉/黄肉以及无花粉/有花粉3 个性状进行了分子标记研究。研究获得SSR 标记UDP96-018 (300 bp) 与有毛性状连锁, 遗传距离4.5 cM, SSR标记UDP98-407 (680 bp) 与白肉性状连锁, 遗传距离为2.2 cM; 根据拟南芥雄性不育序列标记设计的引物扩增出的两个片段NNJ-I (600 bp ) 和NNJ-I (900 bp) 与桃无花粉性状之间的遗传距离为0 cM。这些标记的获得为桃分子标记辅助育种提供了有效的筛选手段。     

白菜耐光氧化能力鉴定及其与活性氧代谢关系的研究

 采用人工光氧化技术对30个常见白菜栽培品种进行光氧化处理, 以总叶绿素存留率作为评价指标, 利用系统聚类分析将供试品种划分为5个级别(1～5级) 。其中耐光氧化能力强的品种有青优4号、暑绿、抗热605、绿扬青、矮抗6号、华王; 不耐光氧化的品种有四倍体矮脚黄、绿星。在此基础上, 以耐光氧化品种抗热605与不耐光氧化品种绿星为材料, 研究了光氧化过程中活性氧代谢的特征。结果表明:在光氧化条件下, 白菜叶片内的抗氧化酶SOD、POD、CAT、APX活性受光氧化诱导升高, 但光氧化敏感性品种绿星的酶活性很快下降, 耐光氧化品种抗热605的酶活持续保持在较高的水平。因此, 绿星的O₂·生成速率、H₂O₂ 含量及MDA的积累量均高于抗热605, 最终导致品种绿星在光氧化下总叶绿素存留率低。表明抗热605植株内较高的抗氧化酶活性对提高耐光氧化能力起了重要作用。     

Iodoacetamide attenuates cognition impairment and amyloid deposit in an AD rat model

AIM:To investigate the effect of an insulin-degrading enzyme (IDE) activator, iodoacetamide, on an AD rat model. METHODS:Thirty-two male Wistar rats were divided into 4 groups:Aβ group, Aβ+ iodoacetamide group, iodoacetamide group and control. Each group included 8 subjects. Aβ was injected into the CA3 area of bilateral hippocampi;Iodoacetamide was administered subcutaneously daily for 5 consecutive days before surgery. The behavior performance in the morris water maze was obtained. The level of Aβ was detected by immunohistochemistry staining and ELISA assay. RESULTS:Level of Aβ was significantly reduced in Aβ+iodoacetamide group compared with that of Aβ group (dropped by 24%), and the Aβ deposit decreased (by 23.9%), the cognition function of this group also greatly improved according to the behavior performance in the morris water maze. The mean escape latency in the place navigation was much lower compared to Aβ group and the times that rats acrossed the central platform in the spatial probe test was also elevated. CONCLUSION:Iodoacetamide significantly reduces the Aβ deposit in the hippocampus in an AD rat model and relieves memory loss.     

天祝县草产业发展的制约因素及其对策

通过分析天祝县草产业发展现状，指出天祝县草产业发展存在的问题，提出要大力发展天祝县草产业必须加强天然草原综合改良，科学合理利用草原资源，建立人工草地和牧草种子繁育基地，开发草产品；建立多元化的投入机制，培植草产业开发的龙头企业；进一步完善草地管理制度，全面彻底地落实草原有偿承包责任制；建立信息网络体系，把信息网络纳入畜牧业基础设施建设范围内，建立健全草畜产品信息网络。     

工程菌DH5a感受态细胞的制备及质粒pGEM的转化研究

绿色荧光蛋白（green fluorescent protein，GFP）是源于海洋生物多管水母(aequoia victoria)的一种发光蛋白，能够自身催化形成生色团并在蓝光激发下发出绿色荧光，能在活细胞内稳定表达，本试验首先从含有GFP的大肠杆菌中提取质粒，并利用胶回收试剂盒纯化质粒，采用氯化钙法将工程菌DH_5a制成感受态细胞，然后将纯化后的质粒转入已制备好的感受态细胞中，使得工程菌DH_5a转化成具有抗氨苄青霉素的大肠杆菌，并表达绿色荧光蛋白，接种于加氨苄青霉素的LB培养基上，筛选阳性克隆。     

猪白细胞介素-18基因表达及重组蛋白的纯化

以pcDNA3.1-IL18为模板进行PCR扩增获得猪白细胞介素-18(IL-18)的成熟肽基因,以KpnⅠ、SacⅠ双酶切PCR产物作为供体,KpnⅠ、SacⅠ双酶切的pET41c和pET32c作为载体,连接载体供体,转化DH5α,经双酶切、PCR鉴定及测序筛选出阳性重组质粒,并命名为pET41c-IL18和pET32c-IL18。将pET41c-IL18和pET32c-IL18转化大肠埃希氏菌BL21(DE3),用1 mmol/L IPTG 37℃诱导表达。SDS-PAGE及W estern-blotting分析结果表明,所表达的重组蛋白主要以包涵体形式存在,pET32c-IL18重组蛋白分子质量约33 ku,与预期大小相符。将包涵体提取物用8 mol/L脲变性,经N i-NTA柱纯化,透析复性,得到了纯化的IL-18蛋白。     

Biological characteristics of JAK2 transduced CD34+ cells from cord blood during ex vivo expansion

AIM: To explore the feasibility and biological characterization of long-term regulated expansion of JAK2 transduced human CD34⁺ cord blood cells in vitro.METHODS: A retrovirus (RV) vector which contains JAK2 catalytic domain and two binding sites for a chemical inducer,dimerization (AP20187),was cloned (designated MGI-F₂JAK2).CD34⁺cells were enriched from cord blood with a MiniMACS system.The purified CD34⁺ cells were transfected with supernatant from the retrovirus packaging cell line that expressed JAK2.Following transduction,cells were expanded into four groups: AP20187 alone,FL alone,TPO,alone,AP20187+FL+TPO,respectively.The expanded cells were monitored by GFP expression,immunophenotyping,progenitor colony assay,karyotype analysis as well as tumorigenesis in nude mice.RESULTS: The purity of selected CD34⁺ cells was over 91% and gene transfer rate was 49.32%±6.21%.Only the group of AP20187 +FL+ TPO was obtained a significant sustained outgrowth of the transduced CD34⁺ cord blood cells.The percentage of GFP+ cells consistently produced a rise to the 90% peak level by the end of 8th week of culture.Flow cytometry analysis showed that the phenotype of the expanded cells was CD33⁺,CD61⁺ and Gly-A⁺ partial positive;CD38⁺ and HLA-DR⁺ strong positive,while CD2,CD7 and CD19 were almost negative.Colony assays performed in methycelluos,which can give rise to BFU-E,CFU-GM and CFU-Mix,the CFU-GM was predominantly in all colonies.The tumor was not observed in nude mice and the karyotype analysis was normal from expanded cells.CONCLUSION: The results demonstrate that AP20187-mediated activation of JAK2 signaling is capable of stimulating expansion JAK2 transduced CB CD34⁺ cells in combination with FL and TPO.This system may have applications for studies in signaling transduction,hematopoiesis,and for gene and cell therapy.