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V V Pogodina

Publications and source records attributed to V V Pogodina.

At least 19 recordsLinked to original sources

Cytopathological changes in human and animals brains in prion diseases.

Studies of histological preparations of the brains of humans and animals with prion diseases showed that neuron vacuolization often starts and develops intensely in the distal segments of dendrites. Two types of neuron body death were noted - cytolysis and pyknosis, the latter usually being associated with vacuolization of dendrites. The involvement of the main types of neuroglia in the pathogenesis of prion diseases was established, which provides grounds for referring to gliosis rather than astrocytosis. Accumulation of phagocytes (microgliocytes, blood macrophages, pericytes) and release of lymphocytes from blood vessels with diffuse infiltration of brain tissues by these cells to form accumulations around degeneratively changed neurons were noted.

Animals↗

Characterization of a siberian virus isolated from a patient with progressive chronic tick-borne encephalitis.

A strain of Tick-borne encephalitis virus designated Zausaev (Za) was isolated in Siberia from a patient who died of a progressive (2-year) form of tick-borne encephalitis 10 years after being bitten by a tick. The complete genomic sequence of this virus was determined, and an attempt was made to correlate the sequence with the biological characteristics of the virus. Phylogenetic analysis demonstrated that this virus belongs to the Siberian subtype of Tick-borne encephalitis virus. Comparison of Za virus with two related viruses, a Far Eastern isolate, Sofjin, and a Siberian isolate, Vasilchenko, revealed differences among the three viruses in pathogenicity for Syrian hamsters, cytopathogenicity for PS cells, plaque morphology, and the electrophoretic profiles of virus-specific nonstructural proteins. Comparative amino acid alignments revealed 10 individual amino acid substitutions in the Za virus polyprotein sequence that were different from those of other tick-borne flaviviruses. Notably, the dimeric form of the Za virus NS1 protein migrated in polyacrylamide gels as a heterogeneous group of molecules with a significantly higher electrophoretic mobility than those of the Sofjin and Vasilchenko viruses. Two amino acid substitutions, T(277)-->V and E(279)-->G, within the NS1 dimerization domain are probably responsible for the altered oligomerization of Za virus NS1. These studies suggest that the patient from whom Za virus was isolated died due to increased pathogenicity of the latent virus following spontaneous mutagenesis.

3' Untranslated Regions↗

[Cytopathological changes in human and animal brain in prion diseases].

The study of brain histological sections of humans and animals afflicted by prion diseases has shown that neuronal vacuolization began in and intensely spread from the distal portions of dendrites. Two types of neuronal cell body death were demonstrated, including cytolysis and pyknosis, the latter being usually associated with dendrite vacuolization. The involvement of major glial types in the pathogenesis of prion diseases was established, which argues against the concept of astrocytosis in favor glyosis. The accumulation of phagocytes (microgliocytes, blood macrophages, pericytes) and emigration of lymphocytes from the blood vessels with diffuse infiltration of brain tissue and formation of aggregates around degenerating neurons, were noted.

Animals↗

[In vivo diagnosis of Creutzfeldt-Jakob disease].

The paper presents the data concerning usage of some original method of vital laboratory diagnostics of Creutzfeldt-Jacob disease that belongs to the group of prionic diseases. The method consisted in the inoculation of inoculative culture of rat Gasser ganglion's neurinoma by biologic materials investigated (serum and clot of blood) with the following passivation and investigation of the contaminated culture by means of both morphologic and electron microscopic methods. As an example of vital verificated case the wide pathomorphologic analysis of the biopsy sample of brain was presented. Besides, the efficiency of the investigation of cognitive evoked potentials (P300) together with EEG was also demonstrated as the method of objectification of the development of dementia in this disease.

Brain↗

Complete sequence of two tick-borne flaviviruses isolated from Siberia and the UK: analysis and significance of the 5' and 3'-UTRs.

The complete nucleotide sequence of two tick-transmitted flaviviruses, Vasilchenko (Vs) from Siberia and louping ill (LI) from the UK, have been determined. The genomes were respectively, 10928 and 10871 nucleotides (nt) in length. The coding strategy and functional protein sequence motifs of tick-borne flaviviruses are presented in both Vs and LI viruses. The phylogenies based on maximum likelihood, maximum parsimony and distance analysis of the polyproteins, identified Vs virus as a member of the tick-borne encephalitis virus subgroup within the tick-borne serocomplex, genus Flavivirus, family Flaviviridae. Comparative alignment of the 3'-untranslated regions revealed deletions of different lengths essentially at the same position downstream of the stop codon for all tick-borne viruses. Two direct 27 nucleotide repeats at the 3'-end were found only for Vs and LI virus. Immediately following the deletions a region of 332-334 nt with relatively conserved primary structure (67-94% identity) was observed at the 3'-non-coding end of the virus genome. Pairwise comparisons of the nucleotide sequence data revealed similar levels of variation between the coding region, and the 5' and 3'-termini of the genome, implying an equivalent strong selective control for translated and untranslated regions. Indeed the predicted folding of the 5' and 3'-untranslated regions revealed patterns of stem and loop structures conserved for all tick-borne flaviviruses suggesting a purifying selection for preservation of essential RNA secondary structures which could be involved in translational control and replication. The possible implications of these findings are discussed.

Animals↗

[The Gerstmann-Sträussler syndrome: new diagnostic possibilities].

On the basis of clinical picture of the disease, data of CT, MRT, psychological study, original laboratory investigation aimed at indication of changes in transposed neuroglia cells induced by the causal agent of subacute spongious transmissible encephalopathies, the diagnosis of patient K., 49 years old, was considered to be: syndrome of Gertsmann-Sträussler [correction of Herstmann Streussler]. Duration of the disease was 2 years. The case was sporadic. The history of the problem, modern views on etiology, pathogenesis of preventive measures are presented.

Animals↗

Nucleotide and deduced amino acid sequence of the envelope gene of the Vasilchenko strain of TBE virus; comparison with other flaviviruses.

A strain of tick-borne encephalitis virus known as Vasilchenko (Vs) exhibits relatively low virulence characteristics in monkeys, Syrian hamsters and humans. The gene encoding the envelope glycoprotein of this virus was cloned and sequenced. Alignment of the sequence with those of other known tick-borne flaviviruses and identification of the recognised amino acid genetic marker EHLPTA confirmed its identity as a member of the TBE complex. However, Vs virus was distinguishable from eastern and western tick-borne serotypes by the presence of the sequence AQQ at amino acid positions 232-234 and also by the presence of other specific amino acid substitutions which may be genetic markers for these viruses and could determine their pathogenetic characteristics. When compared with other tick-borne flaviviruses, Vs virus had 12 unique amino acid substitutions including an additional potential glycosylation site at position (315-317). The Vs virus strain shared closest nucleotide and amino acid homology (84.5% and 95.5% respectively) with western and far eastern strains of tick-borne encephalitis virus. Comparison with the far eastern serotype of tick-borne encephalitis virus, by cross-immunoelectrophoresis of Vs virions and PAGE analysis of the extracted virion proteins, revealed differences in surface charge and virus stability that may account for the different virulence characteristics of Vs virus. These results support and enlarge upon previous data obtained from molecular and serological analysis.

Amino Acid Sequence↗

Variabilities in the antigenic structure of persisting tick-borne encephalitis virus strains.

Antigenic variants in the E protein from persisting tick-borne encephalitis (TBE) virus strains were analyzed using monoclonal antibodies (MAbs) to an analogous protein of the reference Sofyin strain. MAbs to sequential epitopes demonstrated their ability to differentiate persisting TBE virus strains from Sofyin and from each other. Two MAbs (2H3 and 13D6) showed a higher neutralizing activity in the interaction with persisting TBE virus variants as compared to the Sofyin strain. Based on the obtained data, a comparison was made of topologically identical epitopes from the E protein of reference and persisting virus strains. The possibility of increasing the neutralizing activity of MAbs through alterations in the primary structure of sequential antigenic sites is discussed.

Animals↗

[Antibodies to the structural elements of the neuron in patients with amyotrophic lateral sclerosis and in their healthy relatives].

The results of determining antibodies to the structural elements of neuron in the serum and CSF of 100 patients with lateral amyotrophic sclerosis (LAS), in the serum of their relatives (n-67), and in biological fluids of 50 patients suffering from other neurologic diseases allowed the following conclusions to be made. The predominance of antibody demonstration in the CSF of LAS patients over that in the serum may attest to the immune response on the part of the CNS. The presence of antibodies in the relatives (not-blood ones for the most part) of LAS patients suggests an infectious nature of the disease.

Adult↗

Molecular hybridization with cloned fragments of tick-borne encephalitis (TBE) virus cDNA in acute and chronic TBE infection.

Recombinant plasmid DNA was used as a probe to detect tick-borne encephalitis (TBE) virus RNA during incubation period, acute disease and persistent infection of syrian hamsters. Within the first three weeks post-infection the results of direct virus isolation and RNA detection in the brain agreed by a rate of 100%, the virus titre ranging between 10(1.9) to 10(10.5) LD50/ml and viral RNA concentration at 1-1000 pg. At the same time TBE virus RNA was detected in the spleen when the virus titre was greater than or equal to 10(6.5) LD50/ml. By 8 months post infection (p.i.) viral RNA was found in the brain, liver, and spleen in the absence of infectious TBE virus. No viral RNA was present in the thymus. In addition, electron microscopic findings in hamster brain confirmed the hypothesis that TBE virus persistence was accompanied by formation of virus-specific structures but impaired virion maturation.

Acute Disease↗

Development of antibodies to axonal neurofilaments in the progression of chronic tick-borne encephalitis.

We followed the presence of autoantibodies to neurofilaments (NF) in the sera of patients with acute tick-borne encephalitis (TBE), chronic TBE, amyotrophic lateral sclerosis (ALS), and other diseases of CNS. The diagnosis was made according to clinical signs and based on virus neutralizing antibodies. Autoantibodies to NF were found in the majority of chronic TBE patients during disease progression, but were neither present in acute TBE nor in chronic TBE cases during the stabilization phase. Autoantibodies to NF found in a patient with acute TBE showed subsequent progression to a prolonged course. The data are discussed in order to assess the mechanisms of the chronic TBE process and its role in impairing the slow axonal transport.

Amyotrophic Lateral Sclerosis↗

Alterations of arginase activity in scrapie-infected mice and in amyotrophic lateral sclerosis.

We followed the dynamics of arginase activity, the ultrastructural changes, and accumulation of the scrapie agent in the CNS of scrapie-infected mice. The arginase activity has been shown to increase 5-fold within the first 3-4 months of the incubation period followed by subsequent fall at its end. The peak of increased arginase activity coincided with appearance of multilayer membranes, whereas the decrease of this activity was associated with the greatest development of status spongiosus, synaptic degeneration, accumulation of five-layer membranes as well as with maximal accumulation of the scrapie agent in the CNS. Examination of 100 patients with different forms of amyotrophic lateral sclerosis (ALS) revealed a 2-8-fold increase of arginase levels in the cerebrospinal fluid (CSF) as compared with the background levels in the comparative groups of control patients. Similar enzyme alterations in scrapie--and in ALS--are discussed in terms of possible resemblance of their pathogenesis.

Amyotrophic Lateral Sclerosis↗

[Anti-neurofilament antibodies in slow infections of the nervous system].

Twenty-six patients including 12 with lateral amyotrophic sclerosis, 7 with multiple sclerosis, 5 with the Creutzfeld-Jakob disease and 2 with Alzheimer's disease were examined. Antibodies to neurofilaments in the blood serum were detected in all cases of the Creutzfeld-Jakob disease and Alzheimer's disease and in 8 patients with lateral amyotrophic sclerosis with clinical evidence of supranuclear structure involvement. A conclusion is drawn about a certain similarity of pathogenic mechanisms of these diseases, as well as about heterogeneity of the cytoskeleton of neurons in the brain and the spinal cord.

Adolescent↗

Persistence of the scrapie agent in glial cells from rat Gasserian ganglion.

Persistence of the scrapie agent in glial cell monolayers from rat Gasserian ganglion have been studied by electron microscopy, virologic and histologic methods. Under chosen experimental conditions the scrapie agent had been shown to persist in cells for over 2 years. The infected cells appeared to be infectious for BALB/c mice throughout. Persistence of the scrapie agent was associated with development of a marked proliferative effect with increasing mitotic index of the cells. Changes similar to those observed in the CNS in vivo were found by means of electron microscopy. The decreased number of oncovirus-containing cells seems to indicate the decreased proportion of such cells in the culture infected with scrapie agent.

Animals↗

Persistence of tick-borne encephalitis virus in monkeys. VI. Pathomorphology of chronic infection in central nervous system.

Histological changes were studied in the central nervous system (CNS) of 58 Macaca rhesus monkeys, infected intracerebrally (i.c.) and subcutaneously (s.c.) with tick-borne encephalitis (TBE) virus. Subacute degenerative process in the CNS occurred in 7 monkeys on days 15-24 post-infection (p.i.), while chronic degenerative changes were observed in 5 monkeys examined on days 45, 90, 279, 383, 789 p.i. Pathological changes in the CNS of 11 monkeys correlated with the clinical picture of subacute and chronic encephalitis. Chronic lesions were observed in the CNS of 1 monkey with asymptotic infection. The pathomorphology of the CNS lesions was characterized by progressive development of focal changes of various duration.

Animals↗