[pH-dependent fusion of eukaryotic cells, caused by arenaviruses, pathogenic and non-pathogenic for humans]. / pH-zavisimoe sliianie éukarioticheskikh kletok, vyzyvaemoe patogennymii nepatogennymi dlia cheloveka arenavirusami.

The conditions necessary for fusion from inside (FFWI) of the BHK-21 cell culture affected by the Lassa and Mopeya arenaviruses were studied. The fusion was shown to occur only in the slightly acid medium and at lower pH meanings for the Mopeya virus, than for the Lassa virus.

[The Mopeia virus induces pH-dependent "fusion from within" in a BHK-21 cell culture]. / Virus Mopeiia indutsiruet pH-zavisimoe "sliianie iznutri" kul'tury kletok BHK-21.

The capacity of BHK-21 cell culture to produce Mopeia virus (Arenaviridae family) to form syncytium upon acidification of the culture medium to pH 5.5 and lower was demonstrated. The cell fusion requires their active virus production: a virus titre in the culture medium must be at least 10(5) PEU/ml. The inhibition of virus multiplication with ammonium chloride as well as treatment of the cells before the medium acidification with immune serum reduced syncytium formation markedly. No cell fusion was observed upon acidification of the medium immediately after virus adsorption to cells. Thus, the observed cell fusion under the influence of the virus is an "internal fusion" and confirms our previous data on the endocytosis mode of arenavirus penetration into the cell.

[Viral retrograde-like pattern of neuronal degeneration in experimental amyotrophic leukospongiosis]. / O virusnom retrogradnopodobnom tipe degeneratsii neironov pri éksperimental'nom amiotroficheskom leikospongioze.

The pattern of destructive alterations of neurons and their processes at different spinal cord levels in guinea pigs with experimental amyotrophic leukospongiosis (AL) was studied by light and electron microscopy. The destruction of a portion of neurons was found to be of retrograde degeneration type. Electron microscopy of spinal conduction pathways showed that degenerative alterations occurred not only in the neuronal soma or processes but also in synaptic structures. The results indicate primary involvement of nerve cell processes, particularly axons, in experimental AL. It is suggested that AL pathogenesis is pathomorphologically based on the uptake of the agent by axonal terminals.

[Cellular transformation in an MDCK culture caused by the agent of amyotrophic leukospongiosis]. / Obuslovlennaia agentom amiotroficheskogo leikospongioza transformatsiia kletok v kul'ture MDCK.

The possibility of infecting epithelioid MDCK cell culture with the agent of amyotrophic leukospongiosis (AL) was shown. Various morphofunctional changes were observed in the infected cells. In the first subpassage, the saturation density and yields of cells increased, while their mitotic activity decreased and adhesive properties changed. In the second subpassage, the cell morphology and monolayer architectonics changed, the cells losing the ability to form a confluent monolayer. The infected cultures died in further subpassages. Clinical signs of the disease and morphological changes in the CNS typical of AL were observed in the animals infected with a homogenate of cells and culture fluid from the AL-agent-infected cultures.

[Pathology of the reproductive apparatus of cells under the action of remantadine and deitiforin]. / O patologii reproduktivnogo apparata kletok pri deistvii remantadina i deitiforina.

The antiviral effect of chemical agents remantadine and deutephorine on the reproductive apparatus of MDCK-cells was studied. It was established that the action of the chemical agents during 3-4 days induced enhancement in pathologically transformed mitoses. This enhancement was in direct proportion to the doses used and to the cultivation time. Dose dependent enhancement of the total pathological mitoses number was simultaneous with the redistribution of mitoses into groups: the relative number of pathologies connected with chromosome damage became lower and the number of degenerating mitoses grew. Computer regression analysis showed the linear dependence between the chemical agent dose and the number of mitoses in the metaphase, that gives an indirect evidence of statmokinetic action of the agents under study.

[The 3-phase reaction of cells of an MDCK culture to long-term exposure to antiviral chemical preparations]. / Trekhfaznaia reaktsiia kletok kul'tury MDCK na dlitel'noe vozdeistvie protivovirusnykh khimiopreparatov.

A study was made of the effect of antiviral drugs remantadine and deitephorine on dynamics in the changes in structure-function parameters, mitotic activity, protein and nucleic acid synthesis in the Madin-Darby canine kidney cell culture. The application of methodical complex and regression analysis methods, the approximation of experimental data with analytical functions showed general regularity in the monolayer cell population response to the effect of drugs. In the response of cell populations three phases are distinguished: the first phase--transient inhibition; the second phase--relative compensation; the third phase--pathological cell destructive process.

[Virus replication in a culture of smooth muscle cells from the human aorta]. / Replikatsiia virusov v kul'ture gladkomyshechnykh kletok aorty cheloveka.

A new modification of the method for cultivation of cells from blood vessel explants has been proposed, and on its basis several cell lines from different vessels of human embryo and adult subjects have been derived. The sensitivity of vessel cells to viruses was studied on a model of aorta cell culture using a wide spectrum of RNA and DNA viruses. All the strains under study with the exception of respiratory-syncytial virus (RSV) and encephalomyocarditis (EMC) virus induced a productive infection in the cells. The infection with RSV and EMC was abortive. The possibility of virus replication in vessel cells was confirmed by isolation of adenovirus from a human renal artery biopsy.