To investigate the relationship of the variation of virulence and the external capsid proteins of the pandemic duck hepatitis A virus type 1(DHAV-1) isolates,the virulence,cross neutralization assays and the complete ...To investigate the relationship of the variation of virulence and the external capsid proteins of the pandemic duck hepatitis A virus type 1(DHAV-1) isolates,the virulence,cross neutralization assays and the complete sequence of the virion protein 1(VP1) gene of nine virulent DHAV-1 strains,which were isolated from infected ducklings with clinical symptoms in Shandong province of China in 2007-2008,were tested.The fifth generation duck embryo allantoic liquids of the 9 isolates were tested on 12-day-old duck embryos and on 7-day-old ducklings for the median embryonal lethal doses(ELD 50 s) and the median lethal doses(LD 50 s),respectively.The results showed that the ELD 50 s of embryonic duck eggs of the 9 DHAV-1 isolates were between 1.9 × 10 6 /mL to 1.44 × 10 7 /mL,while the LD 50 s were 2.39 × 10 5 /mL to 6.15 × 10 6 /mL.Cross-neutralization tests revealed that the 9 DHAV-1 isolates were completely neutralized by the standard serum and the hyperimmune sera against the 9 DHAV-1 isolates,respectively.Compared with other virulent,moderate virulent,attenuated vaccine and mild strains,the VP1 genes of the 9 strains shared 89.8%-99.7% similarity at the nucleotide level and 92.4%-99.6% at amino acid level with other DHAV-1 strains.There were three hypervariable regions at the C-terminus(aa 158-160,180-193 and 205-219) and other variable points in VP1 protein,but which didn't cause virulence of DHAV-1 change.展开更多
采用三聚磷酸钠和三偏磷酸钠法制备磷酸化绞股蓝皂苷（pGP），然后运用体外细胞培养法比较研究绞股蓝皂苷（GP）和pGP抗DHAV感染鸭胚肝细胞（DEH）的作用。通过MTT法测定了GP和pGP在DEH上的安全质量浓度，并采用先加药物后接种病毒、先...采用三聚磷酸钠和三偏磷酸钠法制备磷酸化绞股蓝皂苷（pGP），然后运用体外细胞培养法比较研究绞股蓝皂苷（GP）和pGP抗DHAV感染鸭胚肝细胞（DEH）的作用。通过MTT法测定了GP和pGP在DEH上的安全质量浓度，并采用先加药物后接种病毒、先接种病毒后加药物和药物与病毒同时感作3种加药方式观察了GP和pGP对DHAV（duck hepatitis A virus）感染DEH的影响。为了进一步验证药物的抗病毒效果，采用实时荧光定量PCR方法比较分析了最有效药物浓度的GP和pGP对DHAV在DEH上的吸附、复制和释放的影响。结果显示：GP和pGP在一定质量浓度下均能促进DEH的生长；GP和pOP都具有较好的体外抗DHAV的作用，且在先加药后加毒和先加毒后加药作用方式下，pGP的抗DHAV的作用效果优于GP；在先加药后加病毒作用方式时，GP和pGP均能有效抑制DHAV的吸附；在先加病毒后加药作用方式时，GP和pGP对病毒吸附鸭胚肝细胞没有明显的作用，但能有效抑制DHAV的复制和释放，且pGP的抑制效果优于GP。结果表明：磷酸化修饰显著提高了GP的抗DHAV作用，pGP有希望被开发成一种新型抗DHAV药物。展开更多
为了明确引起雏鸭胰腺炎的新型鸭1型甲肝病毒（duck hepatitis A virus 1,DHAV-1）的分类地位,通过鸭胚血清交叉中和试验测定并分析其与经典的肝炎型DHAV-1的抗原相关性。经血清交叉中和试验测得抗胰腺炎型DHAV-1阳性血清对胰腺炎型DHA...为了明确引起雏鸭胰腺炎的新型鸭1型甲肝病毒（duck hepatitis A virus 1,DHAV-1）的分类地位,通过鸭胚血清交叉中和试验测定并分析其与经典的肝炎型DHAV-1的抗原相关性。经血清交叉中和试验测得抗胰腺炎型DHAV-1阳性血清对胰腺炎型DHAV-1、经典的肝炎型DHAV-1的中和效价分别为1∶169.8、1∶91.2,而抗肝炎型DHAV-1阳性血清对经典的肝炎型DHAV-1、胰腺炎型DHAV-1的中和效价分别为1∶125.9、1∶89.1。参照同属小RNA病毒科的口蹄疫病毒血清型、亚型的划分标准,计算得出胰腺炎型DHAV-1与经典的肝炎型DHAV-1间的抗原亲源值（R）为0.62,介于0.32-0.7之间,表明胰腺炎型DHAV-1与经典的肝炎型DHAV-1相比其抗原性发生了较大变异,定名为鸭1型甲肝病毒亚型（DHAV-1a）。展开更多
为了解1型鸭甲肝病毒（Duck hepatitis A virus type 1）VP1基因在鸭胚传代中的变异规律,本研究将LY0801株DHAV-1在鸭胚体内传代至30代,分别对1~5、10、15、20、25、30代病毒进行VP1基因的克隆测序。各代次病毒分别以108copies/胚接种9...为了解1型鸭甲肝病毒（Duck hepatitis A virus type 1）VP1基因在鸭胚传代中的变异规律,本研究将LY0801株DHAV-1在鸭胚体内传代至30代,分别对1~5、10、15、20、25、30代病毒进行VP1基因的克隆测序。各代次病毒分别以108copies/胚接种9日龄健康鸭胚,测定各组鸭胚的平均死亡时间和病毒在鸭胚尿囊液中的增殖拷贝数。结果表明：DHAV-1在鸭胚传代过程中,不同代次之间出现12个氨基酸的反复变异和同步变异,分别为R43M（K）、T48A、T101S、L169F、T180I、S181L、R183Q、E184A（K）、G187D、D193N、M213R、H219Y;在传代过程中,病毒致死鸭胚的时间逐渐延迟,但病毒在鸭胚内的增殖拷贝数未呈现稳定增长的趋势。展开更多
基金the Chinese National Natural Sciences Foundation(30871878)Shandong Province Higher Educational Science and Technology Program(J08LF07)the Science and Technology Commission of Shandong Province(2010GNC10914),China
文摘To investigate the relationship of the variation of virulence and the external capsid proteins of the pandemic duck hepatitis A virus type 1(DHAV-1) isolates,the virulence,cross neutralization assays and the complete sequence of the virion protein 1(VP1) gene of nine virulent DHAV-1 strains,which were isolated from infected ducklings with clinical symptoms in Shandong province of China in 2007-2008,were tested.The fifth generation duck embryo allantoic liquids of the 9 isolates were tested on 12-day-old duck embryos and on 7-day-old ducklings for the median embryonal lethal doses(ELD 50 s) and the median lethal doses(LD 50 s),respectively.The results showed that the ELD 50 s of embryonic duck eggs of the 9 DHAV-1 isolates were between 1.9 × 10 6 /mL to 1.44 × 10 7 /mL,while the LD 50 s were 2.39 × 10 5 /mL to 6.15 × 10 6 /mL.Cross-neutralization tests revealed that the 9 DHAV-1 isolates were completely neutralized by the standard serum and the hyperimmune sera against the 9 DHAV-1 isolates,respectively.Compared with other virulent,moderate virulent,attenuated vaccine and mild strains,the VP1 genes of the 9 strains shared 89.8%-99.7% similarity at the nucleotide level and 92.4%-99.6% at amino acid level with other DHAV-1 strains.There were three hypervariable regions at the C-terminus(aa 158-160,180-193 and 205-219) and other variable points in VP1 protein,but which didn't cause virulence of DHAV-1 change.
文摘采用三聚磷酸钠和三偏磷酸钠法制备磷酸化绞股蓝皂苷（pGP），然后运用体外细胞培养法比较研究绞股蓝皂苷（GP）和pGP抗DHAV感染鸭胚肝细胞（DEH）的作用。通过MTT法测定了GP和pGP在DEH上的安全质量浓度，并采用先加药物后接种病毒、先接种病毒后加药物和药物与病毒同时感作3种加药方式观察了GP和pGP对DHAV（duck hepatitis A virus）感染DEH的影响。为了进一步验证药物的抗病毒效果，采用实时荧光定量PCR方法比较分析了最有效药物浓度的GP和pGP对DHAV在DEH上的吸附、复制和释放的影响。结果显示：GP和pGP在一定质量浓度下均能促进DEH的生长；GP和pOP都具有较好的体外抗DHAV的作用，且在先加药后加毒和先加毒后加药作用方式下，pGP的抗DHAV的作用效果优于GP；在先加药后加病毒作用方式时，GP和pGP均能有效抑制DHAV的吸附；在先加病毒后加药作用方式时，GP和pGP对病毒吸附鸭胚肝细胞没有明显的作用，但能有效抑制DHAV的复制和释放，且pGP的抑制效果优于GP。结果表明：磷酸化修饰显著提高了GP的抗DHAV作用，pGP有希望被开发成一种新型抗DHAV药物。
文摘为了明确引起雏鸭胰腺炎的新型鸭1型甲肝病毒（duck hepatitis A virus 1,DHAV-1）的分类地位,通过鸭胚血清交叉中和试验测定并分析其与经典的肝炎型DHAV-1的抗原相关性。经血清交叉中和试验测得抗胰腺炎型DHAV-1阳性血清对胰腺炎型DHAV-1、经典的肝炎型DHAV-1的中和效价分别为1∶169.8、1∶91.2,而抗肝炎型DHAV-1阳性血清对经典的肝炎型DHAV-1、胰腺炎型DHAV-1的中和效价分别为1∶125.9、1∶89.1。参照同属小RNA病毒科的口蹄疫病毒血清型、亚型的划分标准,计算得出胰腺炎型DHAV-1与经典的肝炎型DHAV-1间的抗原亲源值（R）为0.62,介于0.32-0.7之间,表明胰腺炎型DHAV-1与经典的肝炎型DHAV-1相比其抗原性发生了较大变异,定名为鸭1型甲肝病毒亚型（DHAV-1a）。
文摘为了解1型鸭甲肝病毒（Duck hepatitis A virus type 1）VP1基因在鸭胚传代中的变异规律,本研究将LY0801株DHAV-1在鸭胚体内传代至30代,分别对1~5、10、15、20、25、30代病毒进行VP1基因的克隆测序。各代次病毒分别以108copies/胚接种9日龄健康鸭胚,测定各组鸭胚的平均死亡时间和病毒在鸭胚尿囊液中的增殖拷贝数。结果表明：DHAV-1在鸭胚传代过程中,不同代次之间出现12个氨基酸的反复变异和同步变异,分别为R43M（K）、T48A、T101S、L169F、T180I、S181L、R183Q、E184A（K）、G187D、D193N、M213R、H219Y;在传代过程中,病毒致死鸭胚的时间逐渐延迟,但病毒在鸭胚内的增殖拷贝数未呈现稳定增长的趋势。
