异硫氰酸丙烯酯毒杀松材线虫作用机制初步研究

对异硫氰酸丙烯酯毒杀松材线虫作用机制进行了初步研究。测定了其对线虫虫体形态、运动行为、体内总糖和蛋白质含量的影响,以及处理前后线虫体内过氧化氢酶(CAT)、乙酰胆碱酯酶(AChE)和谷胱甘肽-S-转移酶(GST)活性变化。结果表明:经异硫氰酸丙烯酯处理后的松材线虫虫体形态严重扭曲,运动形态出现由正常的S形变化为多节弯曲和螺旋状卷曲等异常状况,线虫行动随时间的推移变得迟缓,最终呈C形、新月形或直接死亡。随着异硫氰酸丙烯酯处理质量浓度的增大,线虫体内总糖和蛋白质含量显著上升,糖和蛋白质的代谢发生紊乱;线虫体内CAT、AChE和GST活性显著降低,且均低于对照组,表明线虫体内氧化和抗氧化作用失衡;细胞受到极大的影响,神经系统遭到破坏,解毒能力明显降低。研究结果可为研究利用异硫氰酸丙烯酯作为植物源杀线虫剂提供依据。     

聚松香丙烯醇酯及其氧化物的合成及表征(Ⅰ)——微波加热法合成聚松香丙烯醇酯

采用微波加热和常规加热方法聚合得到聚松香丙烯醇酯,分别对聚合物进行了红外、紫外、软化点和热失重分析。结果表明,微波加热聚合得到聚松香丙烯醇酯具有交联结构,松香的共轭双键参与了反应,软化点在300℃以上,微波加热反应的聚松香丙烯醇酯的相对分子质量在29 305以上,常规加热方法聚合得到聚松香丙烯醇酯相对分子质量在3 910以上,常规加热方法聚合时加入交联剂后得到的聚合物,相对分子质量在9 729以上,聚合物中残留有更多的双键,聚合物的热稳定性减弱。采用微波加热合成聚松香丙烯醇酯快速简便,聚合物性能优于常规方法。     

Phenethyl isothiocyanate as an anti-nutritional factor attenuates deoxynivalenol-induced IPEC-J2 cell injury through inhibiting ROSmediated autophagy

Deoxynivalenol(DON)is considered to be the most harmful mycotoxin that affects the intestinal health of animals and humans.Phenethyl isothiocyanate(PEITC)in feedstuff is an anti-nutritional factor and impairs nutrient digestion and absorption in the animal intestinal.In the current study,we aimed to explore the effects of PEITC on DON-induced apoptosis,intestinal tight junction disorder,and its potential molecular mechanism in the porcine jejunum epithelial cell line(IPEC-J2).Our results indicated that PEITC treatment markedly alleviated DON-induced cytotoxicity,decreasing the apoptotic cell percentage and pro-apoptotic mRNA/protein levels,and increasing zonula occludens-1(ZO-1),occludin and claudin-1 mRNA/protein expression.Meanwhile,PEITC treatment ameliorated DON-induced an increase of the inducible nitric oxide synthase(iNOS)and cyclooxygenase 2(COX-2)mRNA levels and intracellular reactive oxygen species(ROS)level,and a decrease of glutathione peroxidase 1(GPx1),superoxide dismutase 2(SOD2),catalase(CAT)and heme oxygenase 1(HO-1)mRNA levels.Additionally,PEITC treatment significantly down-regulated autophagy-related protein 5(ATG5),beclin-1 and microtubuleassociated protein 1 light chain 3B(LC3-II)mRNA/protein levels,decreased the number of green fluorescent protein-microtubule-associated protein 1 light-chain 3(GFP-LC3)puncta and phosphatidylinositol 3 kinase(PI3K)protein expression,and up-regulated phospho-protein kinase B(p-Akt)and phospho-mammalian target of rapamycin(p-mTOR)protein expression against DON.However,the activation of autophagy by rapamycin,an autophagy agonist,abolished the protective effects of PEITC against DON-induced cytotoxicity,apoptosis and intestinal tight junction disorder.Collectively,PEITC could confer protection against DON-induced porcine intestinal epithelial cell injury by suppressing ROSmediated autophagy.     

枞酸烯丙酯与异海松酸烯丙酯光固化反应的比较研究

研究了枞酸烯丙酯(AA)和异海松酸烯丙酯(AI)发生UV光固化反应的区别。采用红外光谱法表征双键转化率,两者均随引发剂用量的增加先变大后减小;均随光照时间的增加呈先增大后趋于平缓的趋势,但200 s前,AA的UV固化产物双键转化率高;同等光照强度条件下AA的双键转化率高于AI。在同等固化条件下AA的表干时间比AI短,对应的相对固化速率快。以2-羟基-2-甲基苯丙酮(Darocure-1173)为光引发剂,用量为原料质量的6%,光照时间200 s,光照距离4.5 cm,光照强度100%,在此条件下,AA和AI固化产物的数均相对分子质量分别为4 176和9 407,数均聚合度分别为12和28,两者的UV固化产物均有光滑透明的外观,均具有较好的附着力、耐冲击强度及柔韧性,均通过了耐酸、耐碱、耐盐及耐水性测定,AA和AI的硬度分别为H和HB。     

扩展青霉基因组DNA五种提取方法比较

为寻找一种适合于扩展青霉基因组DNA的提取方法,比较了固体培养、液体静置培养和液体振荡培养3种培养方式的提取效果,分别采用氯化苄法、蜗牛酶法、CTAB法、SDS法及异硫氰酸胍法提取扩展青霉菌基因组DNA,经DNA质量浓度测定及电泳分析,比较5种方法的差异,并利用扩展青霉的多聚半乳糖醛酸酶(Polygalacturonase)基因内一段保守序列,设计PCR引物,扩增大小为288 bp的特异目的基因,检测其灵敏性.结果表明:固体培养的方式较适合扩展青霉基因组DNA的提取,另外5种提取方法均能提取出扩展青霉菌基因组DNA,扩增出目的条带,其中氯化苄法和蜗牛酶法所提DNA的纯度均较好,但蜗牛酶法所提DNA量较少.因此,氯化苄法是5种提取方法中最可靠的DNA提取方法,所提DNA浓度高、纯度好、结果稳定,可作为PCR反应的模板进行特异性扩增,且该方法的最低检测限大约为1.01×10-1μg/mL.     

萝卜肉质根辣味定量分析

用４甲硫基３丁烯异硫氰酸盐（ＭＴＢ－ＩＴＣ）作为辣味的定量指标，用气相色谱法测定其含量。在生食较辣的萝卜榨汁液中ＭＴＢ－ＩＴＣ含量为１００～２００μｍｏｌ／１００ｍＬ。肉质根生长初期其含量较低，定桩期增长最快，近露肩期达最大值，然后逐步下降；在整个生长过程中肉质根不同部位的辣味物质变化趋势一致；辣味物质在萝卜皮（韧皮部）的含量大于萝卜肉（木质部），萝卜肉中，真根部的顶端含量最高，向根头部的方向逐步减少。辣味强弱与播种期早晚有关。     

In vitro effect of recombinant human tumor necrosis factor-alpha on canine neutrophil apoptosis

Neutrophils (polymorphonuclear leukocytes: PMNs) are essential for the host defense against various infections and are often injurious to the host, causing inflammatory diseases where tumor necrosis factor-alpha (TNF-alpha) is suggested to play an important role. Since an effect of TNF-alpha on canine PMN apoptosis has not been studied, canine PMNs were stimulated with recombinant human (rh)TNF-alpha in the present study to investigate the effect of TNF-alpha on canine PMN apoptosis. PMN apoptosis and function to produce ROS were assessed by flow cytometry. Delayed apoptosis was observed in the PMNs treated with rhTNF-alpha at 100 ng/ml, accompanied by retention of capability to produce ROS. However, PMN apoptosis was accelerated by rhTNF-alpha combined with cycloheximide. Therefore, it is indicated that TNF-alpha is able to activate anti- and pro-apoptotic pathways in PMNs and that the inhibition of PMN apoptosis by TNF-alpha requires protein synthesis in the PMNs.     

烯丙基异硫氰酸酯的熏蒸毒力研究

以玉米象和赤拟谷盗作为实验对象,采用熏蒸方式对烯丙基异硫氰酸酯的毒力进行测定.结果表明,烯丙基异硫氰酸酯对所研究的两种害虫有较好的快速致死作用,同时研究发现在相同熏蒸时间内烯丙基异硫氰酸酯对玉米象熏蒸的LC50和LC99均小于对赤拟谷盗的LC50和LC99,这说明烯丙基异硫氰酸酯对玉米象的熏蒸效果比对赤拟谷盗的好.     

用改进的异硫氰酸胍一步法提取完熟水果RNA

以完熟水果为材料提取RNA,除了要最大限度地抑制内源RNA酶活性,严格杜绝外源RNA酶污染外,选择合适的试验材料也是试验成功的关键。选取健壮植株上发育正常的果实,剖取果皮或近果皮果肉组织,在Chomczynski硫氰酸肌一步法的基础上,进行了2次变性,反复抽提,无菌操作等技术改进,获得了满意的纯化效果。