Acta virologica
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Nine strains of Avalon virus were isolated from Ixodes uriae ticks collected in the Cape Sizun seabird reserve, Brittany, from 1979 to 1985, during a longitudinal study of consequences of tick-borne infections for kittiwakes (Rissa tridactyla). Avalon virus strains isolated in France proved difficult to study owing to the weak infectious titres they exhibited in suckling mice or cultured cells. However, some interesting data concerning the ecology of virus infection and the morphology of the virions were obtained and are discussed.
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Two viruses were isolated from a pool of three female Ixodes uriae ticks found on a dead puffin (Fratercula arctica) on a beach at Arbroath, Scotland. Complement fixation tests showed that one of the viruses was an orbivirus belonging to the Kemerovo serogroup and was related to Cape Wrath virus. ⋯ The other virus was of the Uukuniemi serogroup (family Bunyaviridae) and reacted in complement fixation and neutralisation tests with a virus isolated from I. uriae collected from a seabird colony at St Abb's Head, Scotland. Both the orbi- and the uukuviruses replicated in a tick (Rhipicephalus appendiculatus) cell line, RA-243.
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Persistence of tick-borne encephalitis virus IV. Virus localization after intracerebral inoculation.
Tick-borne encephalitis (TBE) virus was isolated from the brains and spinal cords, blood, livers, lymph nodes and kidneys from Macaca rhesus monkeys showing acute and subacute fatal encephalitis. In subacute encephalitis, virus titres in the CNS were lower than in acute disease (3.0--6.2 against 3.8--8.3 log LD50/ml). ⋯ In lymph nodes and spleen, it could be detected only by a combination of methods (co-cultivation in association with fluorescent antibody technique and complement-fixation test, explantation of organ fragments) more sensitive than is the inoculation of mice with organ homogenates. TBE virus was detected by the same methods on day 90 in the CNS and internal organs of a monkey with chronic encephalitis in the stage of remission.
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Crimean-Congo haemorrhagic fever (CCHF) virus was isolated for the first time in Iraq from the blood of three patients. It caused a cytopathic effect in lamb kidney and BHK-21 cell cultures. The virus particles were spherical, enveloped and had 90 nm in diameter similar particles were found in ultrathin sections of the liver from two fatal cases. The isolated virus proved to be antigenically closely related to CCHF virus.
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The approach to the problem of oncogenesis of tumorigenic viruses is compared and analyzed from the position of the Altshtein-Vogt hypothesis and from that of the general theory of oncogenesis advanced by the present author. In contrast to the hypothesis of Altshtein-Vogt dealing mainly with the problem of oncogene origin, the general theory of oncogenesis not only defines concretely the origin of the oncogene and the essence of its product, but also makes it possible to understand why, when and how integration of the oncogene with the genome of the cell leads to the transformation of the cell into a benign cell and when into a malignant tumour cell. An analysis of the essence of the "oncogene position effect" from this standpoint shows that an integration, similar in its mechanism but differing in polarity, of the genome of other viruses with the cell genome should lead to the formation of a corresponding antiviral stable (life-long) immunity or also to the emergence of pseudoautoimmune disease of the type caused by "slow" viruses.