[Objective] The aim of this paper was to study the genotype, pathogenicity and nucleotide difference between Newcastle disease virus(NDV) isolates and traditional NDV vaccine strain(La Sota). [Method] A suspected NDV ...[Objective] The aim of this paper was to study the genotype, pathogenicity and nucleotide difference between Newcastle disease virus(NDV) isolates and traditional NDV vaccine strain(La Sota). [Method] A suspected NDV strain was isolated from a chicken farm. The isolate was preliminarily determined by HA and HI tests. A pair of primers was designed based on the partial sequence of NDV F gene published in GenBank(accession No. JF950510.1). F gene was amplified by RT-PCR, cloned and sequenced. The sequencing result was compared with the F gene sequences published in GenBank, and the phylogenetic tree was constructed to analyze the genotypes. The pathogenicity of the virus was determined by mean death time(MDT) of chicken embryos, intracerebral pathogenicity index(ICPI) of one-day-old chicks and intravenous pathogenicity index(IVPI) of six-week-old chickens, respectively. Based on the NDV genome sequence published in GenBank(accession No. JF950510.1), nine pairs of primers were designed to amplify the genome sequence of the isolate, and its structure was analyzed. [Result] The length of F gene was about 500 bp, and a NDV strain of genotype VII was isolated. The MDT, ICPI and IVPI were 52.8 h, 1.675 and 2.46, respectively, indicating the isolate was a virulent strain. The whole genome sequence analysis results showed that the full genome length of the isolate was 15 192 bp, which had 6 more nu-cleotides than that of La Sota strain, and the homology between the two strains was 82.8%. [Conclusion] A virulent NDV strain of genotype Ⅶ was isolated, with low homology to La Sota strain in nucleotide sequence.展开更多
文摘近年来苯二氮䓬类药物(benzodiazepines,BZDs)及其新型策划药(designer benzodiazepines,DBZDs)在全球范围内的滥用呈现上升趋势.为实时监测区域苯二氮䓬类药物及其新型策划药的使用情况,本文建立了利用固相萃取(SPE)前处理、高效液相色谱串联质谱(LC-MS/MS)技术检测污水中BZDs及其代谢产物的分析方法,并对前处理条件和仪器参数进行了优化,前处理优化过程具体包括固相萃取柱类型、淋洗条件、洗脱条件及复溶条件的选择.最后应用优化后的方法测定北京市6家污水处理厂实际进水样品.结果表明:(1)前处理选用Cleanert PCX萃取柱,依次使用2 mL 2%甲酸水溶液、2 mL甲醇淋洗填料,使用4 mL 5%甲醇氨溶液洗脱目标化合物,氮吹后用500μL 50%甲醇水溶液复溶残留物时效果最优.(2)25种目标化合物不同浓度梯度加标回收率范围为85.7%~116.5%,基质效应、检出限和定量限、标准曲线及线性范围、精密度等指标均满足方法验证要求.(3)实际污水进水样品25种目标化合物可检出18种,浓度在0.03~22.4 ng/L之间,验证了方法的可靠性.研究显示,该分析方法可用于检测生活污水中苯二氮䓬类药物及其新型策划药,可为进一步开展该类药物的污水流行病学研究提供参考依据.
基金Supported by Science and Technology Innovation Leading Talent of Qingdao City(16-8-3-14-zhc)
文摘[Objective] The aim of this paper was to study the genotype, pathogenicity and nucleotide difference between Newcastle disease virus(NDV) isolates and traditional NDV vaccine strain(La Sota). [Method] A suspected NDV strain was isolated from a chicken farm. The isolate was preliminarily determined by HA and HI tests. A pair of primers was designed based on the partial sequence of NDV F gene published in GenBank(accession No. JF950510.1). F gene was amplified by RT-PCR, cloned and sequenced. The sequencing result was compared with the F gene sequences published in GenBank, and the phylogenetic tree was constructed to analyze the genotypes. The pathogenicity of the virus was determined by mean death time(MDT) of chicken embryos, intracerebral pathogenicity index(ICPI) of one-day-old chicks and intravenous pathogenicity index(IVPI) of six-week-old chickens, respectively. Based on the NDV genome sequence published in GenBank(accession No. JF950510.1), nine pairs of primers were designed to amplify the genome sequence of the isolate, and its structure was analyzed. [Result] The length of F gene was about 500 bp, and a NDV strain of genotype VII was isolated. The MDT, ICPI and IVPI were 52.8 h, 1.675 and 2.46, respectively, indicating the isolate was a virulent strain. The whole genome sequence analysis results showed that the full genome length of the isolate was 15 192 bp, which had 6 more nu-cleotides than that of La Sota strain, and the homology between the two strains was 82.8%. [Conclusion] A virulent NDV strain of genotype Ⅶ was isolated, with low homology to La Sota strain in nucleotide sequence.
