[Characteristics of neurovirulence, stability, and immunogenicity of attenuated variants of TP-21 Langat virus]. / Kharakteristiki neirovirulentnosti, stabil'nosti i immunogennosti oslablennykh variantov virusa Langat TP-21.

Clones of Langat TP-21 virus with neurovirulence for primates much lower than that of Elantsev 15-20/3 strain may be obtained by threshold dilutions method on mice. Neurovirulence for monkeys of L1-L5 clones of Langat TP-21 virus obtained at our laboratory was similar to neurovirulence of A.Sabin's type III vaccinal poliomyelitis virus. Attenuated clones of Langat virus are stable and retain protective properties in experiments with mouse protection from pathogenic viruses of tick-borne encephalitis complex.

[The neurovirulence of variants of the Langat TP-21 virus in experiments on different species of lower monkeys]. / Neirovirulentnost' variantov virusa Langat TP-21 v opytakh na nizshikh obez'ianakh raznykh vidov.

Neurovirulence of the attenuated strains of Langat TP-21 virus was tested in monkeys of 5 species: M. mulatta, M. fascicularis, M. nemestrina, C. aethiops, and P. hamadryas. The individual susceptibility of the animals to the infection varied but there was no difference in species susceptibility. The monkeys were more susceptible to intraspinal than to intrathalamic inoculations. The animals not adapted to the laboratory conditions were more susceptible to infection than the adapted ones. The lesions in the spinal cord were the most informative pathomorphological data for differentiation of attenuated strains of Langat TP-21 virus.

[Study of the effect of the cDNA for the human apolipoprotein A-I gene in transgenic rabbits: modeling the neurological syndrome of human Tangier disease]. / Issledovanie na transgennykh krolikakh deistviia kDNK gena apolipoproteid A-I cheloveka: modelirovanie neirologicheskogo sindroma tenzhirskoi bolezni cheloveka.

Two transgenic rabbits which carried human apolipoprotein A-1 (apo A-1) cDNA under mouse ribosomal protein L/32 promoter were obtained. The effectiveness of transgenosis was confirmed by DNA dot/blot and Southern blot hybridizations. Both transgenic animals had paralyses of fore or fore and high limbs. Electron microscopy demonstrated distinct degradative changes of those parts of spinal cord which were responsible for leg skeletal muscle innervation. RNA dot/blot hybridization showed transgene expression in liver and brain but not in kidney of adult transgenic animal. However, analysis of blood serum lipids and immunochemical determinations gave no indications of the presence of human apo A-1 in adult transgenic rabbit. The data obtained allow us to suggest that the observed pathology was due to interference of native and foreign protein products of apo A-1 gene expression in CNS in the course of embryo development. This suggestion was supported by results of in situ hybridization of 5- and 9-week human embryo sections with apo A-1 cDNA, showing effective expression of apo A-1 gene in neural cells of CNS. Results of transgenosis may be viewed as modeling of the neurological syndrome of human Tangier disease.

[Dysontogenesis of the brain of the progeny born to mothers drinking alcohol during pregnancy]. / Dizontogenez golovnogo mozga potomstva materei, upotrebliavshikh alkogol' v period beremennosti.

A study was made of the development of the brain from 44 embryos (5-12 weeks) and 1 fetus (14 weeks) obtained from mothers who used alcohol during pregnancy. 16 cases made up the control group. In 34 cases out of 45 (75.5%), deviations in the development of the brain were established and distributed into the three degrees of gravity: mild, moderate and severe. 11 variants of brain pathology are described. Deviations in the formation of brain walls and disorders of the development of the cortical lamina occurred most frequently (70.6 and 57.9%, respectively). In alcoholic mothers, brain pathology in their progeny was revealed in 100% of cases. Provided they used alcohol systematically and frequently, brain pathology was identified in 83.3% of cases, in systematic rare use of alcohol in 77.3%, and in episodic use of alcohol in 28.5% of cases.

[Proliferative processes in nerve tissue culture under the action of ethanol]. / Proliferativnye protsessy v kul'ture nervnoi tkani pri deistvii étanola.

The authors describe the ultrastructure of an organotypic culture of rat brain cortex exposed to small doses of ethanol. It is shown that the small dose of alcohol (0.5% ethanol) present in the nutrient medium induced proliferation of cytoplasmic membrane structure: hyperplasia of the endoplasmic reticulum with the formation of concentrically located membranes; an increase of the number and size of mitochondria was accompanied by the appearance of the giant, atypical forms of mitochondria; proliferation of vesicular components of Golgi's laminar complex.

[The pathomorphological changes in the brain and internal organs in experimental influenza infection in mice]. / Patomorfologicheskie izmeneniia v golovnom mozge i nekotorykh vnutrennikh organakh pri éksperimental'noi grippoznoi infektsii u myshei.

The possibility of long persistence of influenza virus A in the brain and other organs of mice was established on the basis of complex virological, histological and electron microscopic studies. It was shown that the perivascular oedema of choroid plexus reaches the maximum during late stages of infection, after the clinical recovery. Sharp increase of the permeability of cerebral vessels causing the perivascular oedema, especially in choroid plexus of lateral brain ventricles, proposed to be one of possible mechanisms of pathogenic action of the virus.

[Neuromorphologic studies in pathologic anatomy]. / Neuromorfologicheskie issledovaniia v patologicheskoi anatomii.

In the USSR, pathological neuromorphology that developed at the borderline of pathological anatomy, clinical neuropathology and psychiatry was represented by historically established research schools noted for great achievements. During the past two decades, the number of those skilled in this area has been, however, drastically reduced for a variety of reasons, adversely affecting both the research designs and the pathoanatomic care itself. The paper analyses the present-day pathomorphology of the nervous system in the USSR and provides the possible ways of eliminating the lag existing in the science and the perspectives of its development.

[Effect of ethanol on the morphological characteristics of the cerebral cortex in tissue culture]. / Vliianie étanola na morfologicheskuiu kharakteristiku ku'ltury kory golovnogo mozga.

Light and electron microscopy were used to study the effects of different ethanol concentrations (0.5 and 1%) on the organotypic culture of neonatal rat cerebral cortex. Ethanol produced a biphasic effect. Primarily, the adaptive response of the tissue increased and cell differentiation accelerated. Later, destruction signs accumulated. These changes correlated with the strength and duration of the stimulus. Exposure to 1% ethanol induced the destruction.

[A method of detecting demyelinated nerve tissue in experimental allergic encephalomyelitis]. / Sposob vyiavleniia demielinizatsii v nervnoi tkani pri éksperimental'nom allergicheskom éntsefalomielite.

A method of rapid pathomorphological diagnosis of demyelinization with a simultaneous detection of cell elements in the nervous tissue has been described. The method tested on the model of experimental allergic encephalomyelitis (EAE) is a modified method of Marchi with subsequent staining of histological sections with toluidine blue. Due to a shorter period of nervous tissue exposure to potassium bichromate and osmium acid solutions (from 6-8 weeks to 5 days) the cells preserve their ability to uptake the dye and the endurance of histological sections increases. Their thickness (2-3 microns) makes it possible to examine them in immersion magnification of the light microscope. Using the above method, we succeeded in revealing hematogenic and glial elements in demyelinating foci in the central nervous system of animals with EAE. The method described can be used for studying pathomorphology of multiple sclerosis and other demyelinating diseases in humans and their experimental models, as well as for the express diagnosis of demyelinization in pathoanatomical practice.

Interconnection of demyelination processes and inflammation in the dynamics of experimental allergic encephalomyelitis.

Using a new method for the simultaneous demonstration of myelin breakdown products and cell elements in the demyelinated nervous tissue, a number of previously unknown regularities were revealed concerning interconnection between demyelination processes and inflammation in the dynamics of experimental allergic encephalomyelitis (EAE). Alterations in osmophilia and in size of myelin breakdown products in the demyelination foci are demonstrated to be the most essential in the EAE pathomorphology, a certain type of cellular reaction corresponding to each stage of periaxonal changes. A close relationship was found between demyelination processes and inflammation which determines the structure of the demyelination foci at various stages of the disease.

[Morphologic and biochemical changes in brain cells of mice with influenza]. / Morfologicheskie i biokhimicheskie izmeneniia v kletkakh golovnogo mozga myshei pri grippoznoi infektsii.

The influence of influenza virus infection on the brain cells was studied in mice. Virology, electron microscopy and biochemistry methods were used for this purpose. It has been shown that intracerebral injection of pathogenic strain of influenza virus A/PR/8/34 is accompanied both by the reproduction of virus in the central nervous system tissue and the morphology changes in ependial cells of the vascular plexus of the brain lateral ventricle. It has been found that the level of the lipid peroxidation products in lipid extracts of infected mouse brain is greater than their level in extracts from control mouse brain. It has been concluded that the influenza virus has a damaging effect on the central nervous system cells.

[Dynamics of pathomorphologic changes in experimental allergic encephalomyelitis]. / Dinamika patomorfologicheskikh izmenenii pri éksperimental'nom allergicheskom éntsefalomielite.

The new method of simultaneous identification of myelin degradation products and cellular elements in the demyelinated nervous tissue allowed one to determine some previously unknown regularities in the interaction of demyelination and inflammation processes during experimentally induced allergic encephalomyelitis. The most significant feature in the pathomorphology of this disease is shown to be the change in osmiophilia and the amount of myelin degradation products in the demyelination foci, with every stage of periaxonal changes corresponding to a certain type of cellular reactions. A close relation is revealed between the demyelination and inflammation processes determining the structure of demyelination foci at different stages of the disease.

[Experimental coronavirus encephalomyelitis in mice]. / Eksperimental'nyi koronavirusnyi éntsefalomielit myshei.

A combined comparative virological, morphological, and immunological study of experimental coronavirus encephalomyelitis was carried out in mice in order to elucidate the pathogenetic mechanisms involved in the formation of the foci of lesions in acute and chronic forms of the disease. Intracerebral inoculation of C3H mice with the neurotropic JHM strain of murine hepatitis virus induces a disease with demyelinization foci in the CNS running acute, subacute, or chronic course. This model underlies a concept that demyelinating diseases are caused by viruses producing immunopathologic responses realized via certain histocompatibility loci. The long-term persistence of viral antigen in the CNS and liver may be explained by virus replication in hepatocytes and oligodendrocytes at low levels, and exacerbations of the disease are prevented by the immune system.

The effects of serotonin on the morpho-functional development of rat cerebral neocortex in tissue culture.

The morpho-functional development of the visual area of the cerebral cortex of newborn rats and effects of serotonin (5-HT) on these processes were studied in long-term (up to 40 days) organotypic cultures. It was shown that systematic addition of 5-HT in physiological concentrations to the nutrient medium during cultivation of the explants stimulates glia proliferation, neuron differentiation, neuropil formation, axon myelination and synaptogenesis. Electrophysiological studies of cortical cells in 5-HT-treated cultures showed earlier exhibition of spontaneous activity, increased number (by 33%) of spontaneously firing neurons and prevalence of periodic (bursting) type of discharges. Cultivation of neurons in a medium with 5-HT approximates their sensitivity to 5-HT to that observed in situ. The data obtained are indicative of the stimulating effects of 5-HT on the morpho-functional development of the rat cerebral cortex in tissue culture.

[Effect of serotonin on the development of tissue cultures of the cerebral cortex in the rat]. / Vliianie serotonina na razvitie kul'tury tkani kory golovnogo mozga krys.

The paper deals with morpho-functional development of the visual area of newborn rats cerebral cortex in conditions of prolonged (up to 40 days) organotypical cultivation and with the effect of serotonin (5-OT) on these processes. It has been shown that systematic addition of physiological concentrations of 5-OT to the nutrient medium during explantates cultivation, stimulates glia proliferation, neurones differentiation, neuropyl formation, synaptogenesis and axones myelinization. In media with 5-OT, spontaneous activity of neurones develops earlier, the number of active cells increases by 33%, neurones with periodical bursts prevail in all periods studied. Development of neurones in the medium with 5-OT changes their sensitivity to 5-OT, which becomes close to that in situ.