黄酮类化合物的药理学作用研究进展

对黄酮类化合物的药理作用研究进展进行了综述。黄酮类化合物能抑制或杀死多种菌株,破坏许多病原性病毒,可抑制脂氧酶、环氧酶等重要的炎症酶类;由于黄酮类化合物已被证实具有抑制特异性酶类、清除自由基、细胞毒性等作用,其作为治疗多种常见疾病的药物已经引起了人们广泛的兴趣,比如：某些癌症,心血管疾病和神经衰弱症等。     

MMP-2、MMP-9及TIMP-1、TIMP-2在TPV感染OMK细胞中的表达及其与感染的关系

【目的】研究在特纳河痘病毒(Tanapox virus,TPV)感染枭猴肾上皮细胞(Owl monkey kidney epi-thelial cells,OMK)过程中,基质金属蛋白酶-2(Matrix metalloproteinase-2,MMP-2)、MMP-9和其组织抑制剂(Tissueinhibitor of metalloproteinase,TI MP)TI MP-1、TI MP-2的表达变化及其与感染的关系。【方法】用MMPs高特异性抑制剂(MMP-2Ⅱ、MMP-9Ⅰ)降低MMP-2或MMP-9的活性,研究其对TPV感染的影响和对OMK细胞的毒性。采用明胶酶谱法检测MMP-9和MMP-2在TPV感染过程中蛋白质水平的变化,并应用实时荧光定量PCR方法检测TPV感染中TI MP-1和TI MP-2 mRNA表达水平的变化。【结果】MMP-2和MMP-9的高特异性抑制剂对TPV感染具有显著抑制效果,且对OMK细胞没有毒性作用。在TPV感染OMK细胞过程中,MMP-2和MMP-9蛋白水平升高,而TI MP-1和TI MP-2的mRNA表达水平下降。【结论】MMP-2和MMP-9参与TPV感染,可能对病毒的感染具有促进作用。MMP-2、MMP-9和TI MP-1、TI MP-2比例失衡,造成MMP-2和MMP-9相对"过盛",这可能是MMPs促进TPV感染的重要机制。     

6种病毒抑制剂对烟草花叶病毒的抑制作用及其机制初探

采用半叶枯斑法测定6种病毒抑制剂对烟草花叶病毒(TMV)的活体治疗、保护和钝化作用,并用半定量RT-PCR检测药剂诱导烟叶中病程相关蛋白基因PR-5的表达情况。结果表明:有效成分为宁南霉素的金珠蔬美对TMV有较高的活体治疗和保护效果,在250 mg/L时枯斑抑制率分别达到了67.24%、54.55%;关于药剂对TMV的活体钝化作用,金毒冠氨基寡糖素的抑制率最高,5 mg/L时平均抑制率为60.31%。6种药剂处理烟草K326后,PR-5基因表达呈现不同程度地上调,表明它们均能诱导烟草产生对TMV的抗性。     

四种植物提取物对肉鸡生长性能、肠道及排泄物生化指标的影响

观察比较了樟科（CFPE）、丝兰（YE）、一串红（SS）和桂花（OFL）植物提取物对肉鸡生产性能、肠道和排泄物生化指标的影响。将300只0日龄AA肉鸡随机分为5组：即肉桂、丝兰、一串红和桂花提取物各添加200 mg/kg为试验组,以基础日粮为对照组。每个试验组3次重复,每重复20只。结果表明,与对照组相比,各试验组均可显著提高日增重,降低料肉比（P〈0.05）,显著改善肉鸡肠道内容物和排泄物的生化指标（P〈0.05）：氨态氮、尿素氮、尿酸含量及脲酶活性较对照组呈下降趋势;同时抑制了产脲酶、尿酸酶、尿囊素酶菌以及一些肠道有害细菌的生长,直接抑制粪中尿酸酶活性,从而有效地减少了氨气的逸放,降低其对肉鸡的应激,进而生长性能各项指标都有了改善。     

Occurrence and Stabilities of Oat Trypsin and Chymotrypsin Inhibitors

Nine chymotrypsin and four trypsin inhibitors have been extracted and separated from ungerminated oat grains. The inhibitors fell into two groups, based on their heat and pH stabilities. Members of the most abundant group are labile and are inactivated at 80 °C or at pHs of 3·3 or lower. Members of the second group are stable and are resistant to boiling for 30 min. On germination, the labile inhibitors are inactivated after 2 days and the stable chymotrypsin inhibitors after 3 days. Most of the labile inhibitors from ungerminated grain are destroyed when incubated at 20 °C for 20 h but addition of PMSF, a serine protease inhibitor, prevented their inactivation. Labile inhibitors in extracts of ungerminated oats are inactivated on incubation with an extract prepared from germinated oats, but not in the presence of PMSF. Most oat chymotrypsin and trypsin inhibitors are heat labile and pH sensitive. These inhibitors are apparently inactivated by serine proteinase(s) already present in ungerminated grain.     

Effects of Polyamines Synthesis Inhibitors Sprayed after Heading on Contents and Components of Polyamines in Rice Grains at the Ripening Stage

With a higher polyamine rice （indica variety Jinlingxiang） as experimental material, the changes in contents and components of polyamines （PAs） in rice grains after harvesting were investigated under the treatments by spraying the panicles and flag leaves of rice with PAs synthesis inhibitors, D-Arg （0.5, 1.0, 1.5 and 2.0 mmol/L）, methylglyoxal bis-guanylhydrazone （MGBG） （0.1, 0.5, 1.0 and 1.5 mmol/L） and cyclohexylamine （CHA） （1.0, 5.0, 10.0, 15.0 and 20.0 mmol/L）, at the heading, flowering and grain filling stages. The inhibition of D-Arg on the contents of free and bound PAs and its total amounts in rice grains was significant, especially treated at the flowering and grain filling stages. Treatments with MGBG and CHA affected mainly the components of PAs, and their effects on the total amounts of PAs were not significant except MGBG at the flowering stage and CHA at both heading and flowering stages.