17β-雌二醇对AC细胞活性、细胞周期和超微结构的影响

通过免疫荧光获得雌激素α、β受体在体外星形胶质细胞（Acrocyte,AC）中表达的形态学证据;CCK-8法获得脂多糖（Lipopolysaccharide,LPS）激发AC的适宜浓度。在此基础上,研究了17β-雌二醇（17β-estradiol,E2）对AC的细胞活性、细胞周期和超微结构的影响。结果显示：E2作用AC 48h,10nmol/L E2可提高AC细胞活性和G2＋S%（P〈0.05）,而100,1 000nmol/L E2可降低AC细胞活性（P〈0.05）,100nmol/L E2还可降低G2＋S%（P〈0.05）;100nmol/L E2作用AC 24,48,72h,均可降低AC细胞活性和G2＋S%,以作用48h时抑制作用最强（P〈0.05）;10nmol/L E2可引起AC线粒体数量增加,细胞核分裂增多,但线粒体、粗面内质网结构正常,而100nmol/L E2可导致AC线粒体肿胀或空泡化,粗面内质网扩张或断裂。结果表明,低浓度（10nmol/L）E2促进AC增殖;高浓度（100,1 000nmol/L）E2抑制AC增殖。     

不同浓度雌二醇对猪卵母细胞体外成熟和孤雌激活胚胎的影响

为了探讨雌二醇（17β-estrodiol,E2）对猪卵母细胞体外成熟及孤雌激活后胚胎早期发育的影响,在卵母细胞体外成熟培养基中添加不同浓度雌二醇,研究卵裂率和囊胚率的变化。以未添加雌二醇的基础液为对照组,比较分析各组卵母细胞核成熟效率、孤雌激活后胚胎的卵裂率、囊胚发育率。结果表明,成熟液中添加1μg／mL雌二醇（E2）对猪卵母细胞的体外成熟具有明显的促进作用,而添加100μg／mL雌二醇（E2）对猪卵母细胞体外成熟具有明显的抑制作用。     

牛β-酪蛋白多克隆抗体的制备及鉴定

以牛β-酪蛋白标准品为免疫原,免疫健康的新西兰大白兔,制备了兔抗牛β-酪蛋白的多克隆抗体。经亲和层析纯化后,用SDS-PAGE电泳及考马斯亮蓝染色检测抗体的纯度,经ELISA法测定β-酪蛋白抗体的效价为1∶1600。Western-blot分析发现,制备的抗体与β-酪蛋白可以发生特异性结合,表明成功制备了纯度较高和特异性较好的牛β-酪蛋白多克隆抗体,为乳腺生物反应器的研究提供了有效的工具。     

一株聚β-羟基丁酸（PHB）产生菌的分离纯化及鉴定

本研究从土样中分离纯化出一株PHB高产菌株P-9,通过对其进行形态学和生理生化反应特征研究,初步鉴定为苏云金芽孢杆菌（Bacillus thuringiensis）。进一步研究P-9菌的生长规律,发现P-9菌生长的延迟期为0-24 h,24 h后进入对数生长期,同时积累PHB,84 h时细胞进入稳定生长期,108 h时PHB产量达到最大,达1.25 g/L。     

Varietal Differences in Cell Wall β-(1→3),(1→4)-Glucan and Nonstructural Carbohydrate in Rice Stems during the Grain Filling Stage

Abstract

The contribution of cell wall components and nonstructural carbohydrate (NSC) to grain filling in rice (Oryza sativa L.) was clarified by investigating the differences in the dynamics of hemicellulose, sugar composition of hemicellulose, β-(1→3),(1→4)-glucan, and NSC among cultivars with different grain filling capacities. This investigation was performed using the stems of standard, high yield and low harvest index (HI) cultivars. Hemicellulose concentration in stems tended to decrease slightly during the grain filling stage. This decrease was attributed to a decrease in β-(1→3),(1→4)-glucan concentration, which was detected as a decrease in glucose composition of hemicellulose in the stems during the grain filling stage. The rate of decrease and decrease in the amount of β-(1→3),(1→4)-glucan in the stems differed among the cultivars. These were higher in high yield and high HI cultivars than in relatively low yield and low HI cultivars. Moreover, a positive correlation was observed between the rate of decrease in β-(1→3),(1→4)-glucan and NSC, indicating similarities in the dynamics of β-(1→3),(1→4)-glucan and NSC among the cultivars. When the top half of panicle was removed, β-(1→3),(1→4)-glucan and NSC concentrations in the culm and leaf sheath did not decrease during the grain filling stage. Therefore, the β-(1→3),(1→4)-glucan in stems might be one of the sources that supply substrate to panicle as well as NSC.     

Decomposition of (1–3,1–4)-β-Glucan and Expression of the (1–3,1–4) -β-Glucanase Gene in Rice Stems during Ripening

Abstract

To elucidate the possible participation of hemicellulose decomposition in lodging resistance, we studied the change of hemicellulose and cellulose content in the stems of rice during the ripening stage by methylation analysis and the expression of related genes by Northern blotting. In the rice stem in ripening stage, content of (1-3,1-4)-β-glucan, a component of hemicellulose, decreased markedly although the content of arabinoxylan, a major component of hemicellulose, and cellulose showed little change during the same growth period. On the other hand, expression of the Gns 1 gene, which may encode (1-3,1-4) -β-glucanase that catalyzes the degradation of (1-3,14) -β-glucan, increased sharply in the stem. The mechanism of decomposition of (1-3,1-4) -β-glucan in rice stem and the possible association with lodging resistance is discussed.     

乳腺特异表达载体缺失片段的鉴定与修复

通过对pBC1中的乳腺特异表达启动子成分进行分析,鉴定了位于β酪蛋白启动子上游两个EcoRⅠ位点(-89~-94和-120~-125)之间的缺失片段,31bp的缺失使得该载体中的一个乳控盒元件(-112~-141)和一个乳腺因子识别序列(-92~-102)遭到破坏,并使得位于TATA框上游的所有启动子成分发生了位置改变。通过与山羊β酪蛋白启动子序列进行比较,设计并合成了缺失片段,经一系列的酶切和连接处理,使得该缺失得到了修复,修复后的载体具有所有乳蛋白表达需要的启动子调控原件。本试验结果为利用修复后的乳腺特异高效表达载体进行乳腺生物反应器的研究奠定了分子生物学基础。     

产气荚膜梭菌B型C58-1株β1毒素基因的克隆表达

利用PCR技术,从B型产气荚膜梭菌中国标准株C58-1株扩增出β1毒素基因,连接pMD18-T 载体筛选阳性克隆,然后用限制性核酸内切酶BamHⅠ和SalⅠ对其进行酶切,回收927 bp的β1毒素基因片段,将其定向克隆到载体pET-32a中,获得重组质粒pETβ927。将pETβ927转化至受体菌BL21(DE3)中,其表达产物经His-Trap FF预装柱纯化、SDS-PAGE 检测目的蛋白大小和分布及Western blotting检测其反应原性。结果表明,完整的β1毒素基因大小为1 011 bp,与GenBank发表的B型和C型产气荚膜梭菌β1毒素蛋白序列同源性达99.4%以上;SDS-PAGE结果显示重组目的蛋白在大肠杆菌中成功表达,融合蛋白大小为 54 ku,在超声波裂解上清和包涵体中均有分布,但以包涵体为主。Western blotting检测结果显示表达的重组蛋白可与特异性血清抗体发生免疫反应,表明β1毒素蛋白具有较好的反应原性。     

复方β-环糊精莪术油栓的制备及质量检查

【研究目的】为了防止复方莪术油栓中有效成份的挥发,提高栓剂的溶解性,制备复方β-环糊精莪术油栓;【方法】采用饱和水溶液法制备莪术油β-环糊精包合物,将包合物和甲硝唑等以热熔法制成栓剂并依据兽药典进行质量检查;【结果】试验结果表明在薄层色谱图中,莪术油包合物与莪术油斑点一致,Rf值差异不显著。包合物中含油率为3.6％,油的收率为32.4％,包合物的收率为86.1％。栓剂重量在1.0g～3.0g之间者重量差异限度为±7.5％;栓剂均在30min内全部溶解;【结论】包合过程没有改变莪术油的化学成分,栓剂的质量符合2005版兽药典规定。     

露水草加工粒径和其β-蜕皮激素释放的关系

[目的]比较不同粒径露水草（Cyanotis arachnoidea C.B.Clarke）对所含β-蜕皮激素释放的影响。[方法]采用GRACEODSC18色谱柱（250mm×4.6mm,5μm）,流动相甲醇：水=40：60（V/V,%）洗脱。柱温26℃,流速1.0ml/min,检测波长248nm。[结果]相同来源的露水草粉体（粒径10、30、50μm）β-蜕皮激素含量检测值和普通细粉（粒径180μm）相比,粉体中蜕皮激素激素的检测值平均高1倍多。[结论]露水草粉体中的蜕皮激素更容易溶于甲醇,其提取率明显高于普通细粉。表明露水草经过超微粉碎后,细胞破壁率到得明显提高,更有利于有效成分的溶出。