[The characteristics of the pathogenic properties of new strains of viruses of the California encephalitis antigenic complex isolated in Arkhangelsk Province]. / Kharakteristika patogennykh svoistv novykh shtammov virusov antigennogo kompleksa kaliforniiskogo éntsefalita, izolirovannykh v Arkhangel'skoi oblasti.

Neurotropic properties of Leiv 12724 Ax and Leiv 13004 Ax strains were demonstrated by inoculation of green monkeys, Syrian hamsters and white mice using different routes. The strain Leiv 13004 Ax showed more marked pathogenicity for monkeys and rodents producing lesions in all parts of the brain: temporal, frontal, occipital, cerebellar, medulla oblongata and spinal cord where productive vasculitis, perivascular infiltrations, hemorrhages, and dystrophy of nerve cells were observed. In hamsters, the strains Leiv 13004 Ax and Leiv 12724 Ax inoculated subcutaneously produced latent infection with long-term virus carrier state.

[A comparative experimental study of pathogenic properties of new strains of California encephalitis virus serogroups]. / Sravnitel'noe izuchenie patogennykh svoistv novykh shtammov virusa serogruppy Kaliforniiskogo éntsefalita véksperimente.

Experiments in noninbred mice, Syrian hamsters and grey monkeys were made to characterize the pathogenic properties of new strain of the California encephalitis serogroup isolated for the first time on the island of Taimir, in the Murmansk, Leningrad, Tver regions and in Karelia. All the strains displayed marked tropism for the CNS. The strains isolated in the northern regions of this country turned out more pathogenic for the animals. The strain Leiv-12812 Kl (isolated in the Tver region) differed from the remaining ones in more pronounced pathogenicity for the monkeys, as well as in the site and intensity of brain lesions. The persistence of the virus in hamsters organs may play a role of a reservoir of infection in nature.

[An experimental infection caused by the Issyk-Kul arbovirus]. / Eksperimental'naia infekstiia, vyzvannaia arbovirusom Issyk-Kul'.

Pathogenic properties of Issyk-Kul virus have been experimentally studied in green monkeys, golden hamsters and white mice. The virus was identified in the blood and organs of all the animals. Pathohistological studies have revealed inflammatory and dystrophic changes in the central nervous system, lungs, liver and kidneys. Pronounced immunomorphological changes have been observed in the spleen. The virus possessed pantropic properties and caused generalized infection in all the animals irrespective of the mode of infection. In monkeys asymptomatic infection was accompanied by marked organ damages and virusemia. The presence of specific antibodies in the blood indicated a low efficacy of humoral immunity in this infection.

[Experimental infection caused by Issyk-Kul' arbovirus]. / Eksperimental'naia infektsiia, vyzvannaia arbovirusom Issyk-Kul'.

Experimentally in green monkeys, Syrian hamsters and white mice the authors studied the pathogenic properties of a new virus Issyk-Kul. The virus was determined in all animals--in blood and organs (brain, lungs, liver, spleen, kidneys). During the histological investigation the inflammatory and dystrophic injuries were established: in CNS, lungs, liver and kidneys. There was a distinct immunomorphological reaction in the spleen. The virus has pantropic properties and causes a generalized infection in animals.

Biological profile of a virus belonging to California encephalitis complex isolated in Karelian Autonomous Soviet Socialist Republic.

We investigated in white mice and in Syrian hamsters the pathogenesis of infection with a virus belonging to the California encephalitis complex isolated in the Karelian Autonomous Soviet Socialist Republic. The pathogenic properties of the virus were investigated also in green monkeys. The localization and character of lesions in the organs of given animals appeared to be similar. The virus appeared to possess neurotropic activity, it propagated in the animal body by haematogenous route. The virus was found to be heat-resistant and pH-sensitive.

[Antiviral activity of ribamidyl in experimental infections with California encephalitis group viruses]. / Protivovirusnaia aktivnost' ribamidila pri éksperimental'nykh infektsiiakh virusami kompleksa kaliforniiskogo éntsefalita.

A preparation of ribamydil, an analogue of natural nucleosides, synthesized at the Latvian SSR Institute of Organic Chemistry showed a sufficiently high activity against bunyaviruses of California encephalitis complex both in vitro and in vivo. Various modifications of the enzyme immunoassay may be used for control of the effectiveness of treatment with this drug. Some advantages of the subcutaneous route over the intramuscular one were found. Ribamydil may be useful for treatment of infections of California encephalitis complex.

[Results of infecting experimental animals and monkeys with Karshi virus]. / Rezul'taty zarazheniia laboratornykh zhivotnykh i obez'ian virusom Karshi.

The paper presents the results of a comparative experimental study of pathoginicity of the Karshi virus (Flaviviridae) isolated from Ornithodoros papillipes ticks collected in Uzbekistan, for white mice, Syrian hamsters and green monkeys using various administration routes. Localization and types of lesions (brain, lungs, liver, spleen, kidneys) as well as the presence of viruses in blood and body organs are described basing on histological and virusological studies. Specific antibodies are found in monkeys' blood sera. Hematogenic route of distribution of the virus and its pantropical character are revealed. White mice are found to be the most sensitive model.

[Biological properties of the Tahyna virus isolated in the Arctic]. / Nekotorye biologicheskie svoistva virusa Tiaginia, vydelennogo v Zapoliar'e.

The results are presented of comparative studies over the course of experimental Tahyna infection of viremia in the blood and organs, localization and patterns of lesions in the same organs after different routes of inoculation of white mice and hamsters with a new strain LEIV 9843 Mur of Tahyna virus. The results of these experiments are compared with similar studies in monkeys with asymptomatic infection, including humoral antibody detection. The pattern of lesions in the organs of animals infected with Tahyna virus (LEIV 9843 Mur strain), the mode of virus spread, tissue tropism of the virus were established. The virus thermostability and sensitivity to different pH values of the medium were determined.

[Comparative characteristics of the pathogenicity of 2 viruses of the family Rhabdoviridae for monkeys]. / Sravnitel'naia kharakteristika patogennosti dlia obez'ian dvukh virusov semeistva Rhabdoviridae.

Pathogenic properties of two viruses, Sowgrass and Barur, of the Rhabdoviridae family, isolated in different geographical zones were studied comparatively in green monkeys. These viruses showed different pathogenicity for monkeys by the intracerebral and subcutaneous routes of inoculation. Sowgrass virus had no manifest pathogenicity for monkeys, whereas Barur virus caused death of the animals in 5-6 days after intracerebral inoculation with typical localization of lesions in the brain. Subcutaneous inoculation of the animals produced no fatalities; slight lesions in organs and production of virus-neutralizing antibodies in the blood were observed.

[Use of an immunoenzyme method for research on antichlamydial sera]. / Ispol'zovanie immunofermentnogo metoda dlia issledovaniia antikhlamidiinykh syvorotok.

Data on comparative studies of the sensitivity of enzyme-linked immunosorbent assay (ELISA), complement fixation test (CFT), and indirect immunofluorescence test (IIFT) in titration of antibodies to chlamydial agents of calf enteritis and pneumonia in sera of immunized rabbits are presented. The data indicate that ELISA is 10-40 times more sensitive than CFT and IIFT and may be used for large-scale diagnostic studies in chlamydial infections of cattle.

[Pathogenic properties of the LEIV23 Astrakhan strain of Batai virus for primates]. / Patogennye svoistva dlia primatov virusa Batai, shtamm LEIV23 Astrakhan'.

Pathogenic properties of Batai virus, LEIV23 Astrakhañ strain, isolated from Aedes vexans mosquitoes in Astrakhañ region were studied comparatively. The degree of susceptibility to the virus of green monkeys and rodents (white mice, Syrian hamsters), and the pattern of lesions produced by the virus in organs of these animals were established. The virus was shown to have a comparatively wide host range affecting phylogenetically far distant animals. Monkeys were found to have virus-carrier state for 50 days (the observation period). The virus is pantropic. Apparently mammals may be virus hosts in nature, but human infection cannot be ruled out. This requires further study in an epidemiological experiment.

[Fatty acids of the cerebrosides (1-beta-glycosylceramides) and sulfatides (sulfoglycosylceramides) of the brain of the river lamprey Lampetra fluviatilis]. / Zhirnye kisloty tserebrozidov (1-beta-glikoziltseramidov) i sul'fatidov (sul-foglikoziltseramidov) golovnogo mozga rechnoi minogi Lampetra fluviatilis.

The analysis of the fatty acids of cerebrosides and sulfatides from the brain of the lamprey L. fluviatilis has been carried out. Only normal fatty acids were revealed by TLC of total methyl esters of the fatty acid of cerebrosides and sulfatides. The hydroxy fatty acids are apparently absent. The composition of the normal fatty acids of cerebrosides and sulfatides is very similar. TLC revealed fatty acids containing from 14 to 27 C mainly saturated and small amount of monoenes. The fatty acid pattern of cerebrosides and sulfatides from lamprey brain resembles that from the brain of other vertebrates. The peculiarity of the fatty acid composition of these glycolipids in the lamprey brain is the high proportion of short chain (C14--C18) saturated acids, especially of palmitic acid. The fatty acid composition of cerebrosides and sulfatides from lamprey brain which does not contain myelin is rather similar to that of mammalian brain in early development before the onset of myelination.

[Causative agent of benign lymphoreticulosis]. / Vozbuditel' dobrokachesvennogo limforetikuleza.

A causative agent ("D" strain) was isolated from the contents of an affected lymph node of a patient with beningn lymphoreticulosis. According to the biological and antigenic properties this agent is identified with Chlamydia but is a distinct species. The chlamydial etiology of benign lymphoreticulosis is determined also by the complement-fixation test with sera from convalescents.