Studies on Swine Enteroviruses

Of 38 new isolates of enterovirus recovered from fecal specimens of Japanese pigs, 14 isolates were found to be strains of a new serotype (represented by strain IPI) distinct from the five serotypes of swine enterovirus hitherto recognized in Japan. The remaining isolates included serotypes Teschen, T80, SF1 and V13. The two different types of cytopathic effect, which have been recently recognized in swine kidney cell cultures, were also observed with our isolates; type I is characterized by a rounding of cells followed by aggregation and destruction of affected cells, and type II by granulation and degradation of cells with poor clumping of affected cells. Of interest is the finding that the type I strains possess a higher heat stability than the type II strains when heated at 50 C for one hr.     

猪戊肝病毒存在准种现象

为研究猪戊肝病毒准种存在情况,采用逆转录-巢式聚合酶链反应法(RT-nested-PCR)对四株猪戊肝病毒(Hepatitis E virus)第2可读框(ORF2)部分序列进行PCR扩增,将产物克隆后,每个毒株分别随机挑取20个阳性克隆测序,进行DNA序列分析。结果显示4株HEV不同克隆间的ORF2核苷酸序列同源性分别为96.8%~99.7%、98.8%~99.7%、98.8%~99.7%和100%,有变异的克隆核苷酸序列与上海株(SAAS-JDY5)同源性为96.8%~100%。由此证实感染戊肝病毒的猪个体内存在HEV准种。     

Swine in cardiovascular research

Swine are being chosen with increasing frequency as subjects for cardiovascular research. Similarities to humans in their cardiovascular physiology, size, anatomy, and the perfusion distribution of blood flows make them better subjects than most species. In addition, swine can be less expensive than dogs and primates and they generally are not associated with the same high concern as other species about humane issues.