Vaccinia virus variants as presumable cause of vaccinial complicationsEhrengut, W.; Sarateanu, D.; Alswede, U.; Habib, A.; Tetzlaff, G.
doi: 10.1007/BF01317965pmid: 1180697
Two vaccinia viruses isolated from patients with vaccinial complications (vaccinial ulcer, postvaccinial seizures) showed qualitative differences from the original parental strain. After intradermal injection of the viruses into the rabbit marked necroses developed, which the original strains did not produce. While the parental virus did not grow on the chorioallantoic membrane at 41°C after 2 days incubation, the vaccinia variant produced typical lesions at that temperature. Also the yield of infectious virus on various cell systems was 1–2.5 logs higher for the virus than for the original vaccine strain. With the plaque technique differences were seen in the appearance and size of plaques between the variant and the parental vaccinia strain. These results indicate that virus of an increased pathogenicity could be isolated from the patients and this might be causally connected with the postvaccinial complications from which they were suffering.
Antigenic comparison of swine influenza virus isolatesNath, D.; Rodkey, L.; Minocha, H.
doi: 10.1007/BF01317967pmid: 241310
Cross hemagglutination inhibition (HI) and neuraminidase inhibition (NI) tests demonstrated strong antigenic relationship between A/Swine/Wisconsin/1/73 (SW/73) and A/Swine/Shope/15/31 (SW/31) influenza viruses. An eightyone fold purification of virus was achieved by adsorption and elution followed by differential ultracentrifugation and sedimentation through linear sucrose gradient. Radio-immunoassay using purified125I labeled viral antigens revealed antigenic variation between the two virus isolates. Neuraminidase of both viruses had pH optima between 6.5 and 7.0, and SW/31 enzyme was relatively more heat stable than SW/73.
Structural and growth characteristics of two avian reovirusesNick, H.; Cursiefen, D.; Becht, H.
doi: 10.1007/BF01317969pmid: 170888
Two virus strains which had been suspected to be the etiological agents of infectious bursitis (Gumboro disease) and of inclusion body hepatitis of chickens were characterized by their morphology, their peptide composition and the segmented genome of their double-stranded RNA to be typical reoviruses. Although the 2 avian strains did not clearly differ in their serological behaviour, the size of some of their RNA segments were not identical. Both strains replicated in tissue cultures prepared from the chorioallantoic membrane of embryonated eggs with growth characteristics of reoviruses.