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1.
Phys Rev Lett ; 86(2): 187-91, 2001 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-11177788

RESUMO

We suggest a closed form expression for the path integral of quantum transition amplitudes. We introduce a quantum action with parameters different from the classical action. We present numerical results for the harmonic oscillator with weak perturbation, the quartic potential, and the double well potential. The quantum action is relevant for quantum chaos and quantum instantons.

2.
Bioorg Khim ; 24(2): 100-11, 1998 Feb.
Artigo em Russo | MEDLINE | ID: mdl-10335405

RESUMO

A number of peptides, fragments of the envelope protein E of the tick-borne encephalitis virus (Sofjin strain), were synthesized. Their binding to the polyclonal antiserum to protein E was studied. Rats were immunized with both the free peptides and their KLH-conjugates, and the resulting antisera were tested for their reactivity toward protein E and for their neutralizing activity toward the virus in cell culture. The only peptide corresponding to the 98-113 sequence of protein E was shown to be bound by the protein E antiserum in EIA. Two-fold immunization of rats with KLH-conjugates of the peptides corresponding to the 98-113, 130-143, and 394-403 sequences of protein E resulted in antipeptide antibodies capable of binding the native protein E, and the antibodies to the 98-113 and 394-403 peptides were capable of neutralizing the virus.


Assuntos
Antígenos Virais/química , Vírus da Encefalite Transmitidos por Carrapatos/imunologia , Fragmentos de Peptídeos/química , Sequência de Aminoácidos , Animais , Antígenos Virais/imunologia , Linhagem Celular , Hemocianinas/química , Sondas Moleculares , Dados de Sequência Molecular , Testes de Neutralização , Ratos , Suínos , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/imunologia
3.
Virus Res ; 30(1): 1-16, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7505512

RESUMO

The arrangement of envelope protein epitopes of tick-borne encephalitis viruses (TBEV) (persulcatus or eastern subtype, Sofjin strain and ricinus or western subtype, Minsk-256 strain) and Kyasanur Forest disease virus (KFDV) was investigated using competitive binding of monoclonal antibodies against the Sofjin E protein. The E protein of TBEV Sofjin strain forms three antigenic domains: E1, E2 and E3, represented by 12, 9 and 2 epitopes respectively; two additional epitopes stand alone. Domains E1 and E2 are heterogeneous. On the epitope map of the Minsk-256 strain domain E3 remains intact, domains E1 and E2 overlap and the relative arrangement of virus-neutralizing epitopes from E1 and E2 domains is changed. The epitope map of KFDV is significantly dissimilar to TBEV. The viruses can be distinguished by epitopes with identical serological reactivity. A satisfactory agreement between our epitope maps and previously published antigenic models of flavivirus envelope protein (Guirakhoo et al., 1989; Mandl et al., 1989a) was observed. The main difference of our map is that domains corresponding to domains B and C (Sofjin strain) and A, B and C (Minsk-256 strain) in Heinz's model are overlapping. The results of competition analysis depend on the nature of the antigen (virion or purified protein) and the immunoassay technique.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/imunologia , Epitopos/análise , Proteínas do Envelope Viral/imunologia , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos/imunologia , Ligação Competitiva
4.
Bioorg Khim ; 17(3): 334-42, 1991 Mar.
Artigo em Russo | MEDLINE | ID: mdl-1712201

RESUMO

The largest cyanogen bromide fragment (GP-14,5; coordinates 78-176) of E protein belonging to the envelope of the tick-borne encephalitis (TBE) virus (Far Eastern subtype, strain Sofjin) interacted with five out of twelve E-specific monoclonal antibodies (MAbs). Having compared; efficiencies of some MAbs binding to the antigens of TBE viruses of Far Eastern and West European subtypes and primary structures of analogous peptides of these viruses, we suggested the epitopes of these MAbs to be located in the vicinity of 89 and/or 116-th amino acid residues of E protein. Effect of denaturing agents and reduction followed by carboxymethylation on the protein E antigenic properties was studied.


Assuntos
Anticorpos Monoclonais , Antígenos Virais/imunologia , Vírus da Encefalite Transmitidos por Carrapatos/imunologia , Proteínas do Envelope Viral/imunologia , Western Blotting , Brometo de Cianogênio , Eletroforese em Gel de Poliacrilamida , Epitopos/imunologia , Mapeamento por Restrição , Proteínas do Envelope Viral/genética
6.
Vopr Virusol ; 36(1): 27-31, 1991.
Artigo em Russo | MEDLINE | ID: mdl-1713371

RESUMO

Nucleic acid spot hybridization with cloned cDNA of tick-borne encephalitis (TBE) virus, strain Sofjin, was used to differentiate strains of TBE and other flaviviruses. The cDNA probe reacted with strains of TBE and flaviviruses of TBE subgroup with the exception of Powassan virus. The probe did not react with viruses of Japanese encephalitis and Gendue subgroups. The viruses of TBE subgroup and some strains of TBE virus were differentiated from TBE strain Sofjin by thermal stability of RNA-DNA hybrids. Negishi and Louping ill viruses were found to be most closely related to TBE strain Sofjin among viruses of the TBE subgroup.


Assuntos
DNA Viral/genética , Vírus da Encefalite Transmitidos por Carrapatos/classificação , Hibridização de Ácido Nucleico/genética , RNA Viral/genética , Animais , Encéfalo , DNA/genética , Sondas de DNA/isolamento & purificação , Vírus da Encefalite Transmitidos por Carrapatos/genética , Genes Virais/genética , Técnicas Genéticas , Camundongos , RNA/isolamento & purificação
7.
J Gen Virol ; 71 ( Pt 7): 1505-15, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2374007

RESUMO

Cloned cDNA and synthetic deoxyoligonucleotides, complementary to various parts of the genomic RNA of tick-borne encephalitis virus (TBEV), strain Sofjin, were used to distinguish between strains of TBEV and other flaviviruses. The cDNA probe hybridized with strains of TBEV and related flaviviruses of the TBE complex except for Powassan virus, and it did not react with flaviviruses of the Japanese encephalitis and dengue subgroups. Viruses of the TBE complex and some strains of TBEV were differentiated from TBEV strain Sofjin by the thermal stability of RNA-DNA hybrids. Negishi and louping-ill viruses were the most closely related to TBEV strain Sofjin, among viruses of the TBE complex. Eight strains of TBEV isolated in different geographical areas from different sources were tested by dot-hybridization with 11 deoxyoligonucleotide probes. The probes revealed genetic variations among strains of TBEV. The pattern of hybridization correlated with the source of virus strains: TBEV strains isolated from TBE patients reacted with more probes than strains isolated from ticks. Within a group of epidemic strains of TBEV there was a correlation between the geographical area of isolation and similarity to TBEV strain Sofjin.


Assuntos
DNA Viral/genética , Vírus da Encefalite Transmitidos por Carrapatos/genética , Genes Virais , RNA Viral/genética , Sequência de Aminoácidos , Sequência de Bases , Sondas de DNA , Vírus da Encefalite Transmitidos por Carrapatos/classificação , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Humanos , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Sondas de Oligonucleotídeos/síntese química , Homologia de Sequência do Ácido Nucleico , Termodinâmica
8.
Vopr Virusol ; 34(6): 694-8, 1989.
Artigo em Russo | MEDLINE | ID: mdl-2517368

RESUMO

Characterization of 12 clones of monoclonal antibodies (MAb) generated for the main immunogen of tick-borne encephalitis virus, glycoprotein E, is presented. The following MAb parameters have been determined: constants of binding with antigen, classes and subclasses of immunoglobulins, the activity in two variants of solid-phase enzyme-immunoassay, binding with protein A, and MAb behavior in serologic tests: hemagglutination-inhibition, diffuse precipitation in agar, and virus neutralization. The preliminary studies revealed the presence in these MAb of at least three groups of antibody complementary to various nonoverlapping sites on the structural virus glycoprotein. Further employment of these MAb in practical and research work is discussed.


Assuntos
Anticorpos Monoclonais/isolamento & purificação , Vírus da Encefalite Transmitidos por Carrapatos/imunologia , Glicoproteínas/imunologia , Proteínas Estruturais Virais/imunologia , Animais , Ensaio de Imunoadsorção Enzimática , Hibridomas , Imunodifusão , Camundongos , Camundongos Endogâmicos BALB C
11.
Vopr Virusol ; 29(6): 701-6, 1984.
Artigo em Russo | MEDLINE | ID: mdl-6528577

RESUMO

V3 glycoprotein isolated from virions of two antigenic types of TBE virus was found to be a valuable immunogen in experimental immunizations of rabbits and mice. The immune sera contained high titres of antibodies to TBE virus and other viruses of the TBE antigenic complex detectable in three serological tests. Species-, type-, and group-specific antibodies to TBE viruses were demonstrated. Mice vaccinated with TBE V3 glycoprotein developed immunity to TBE virus challenge. The isolated V3 glycoprotein of TBE virus, like whole TBE virus virions, carries several antigenic determinants.


Assuntos
Antígenos Virais/imunologia , Vírus da Encefalite Transmitidos por Carrapatos/imunologia , Glicoproteínas/imunologia , Proteínas do Envelope Viral/imunologia , Adsorção , Animais , Anticorpos Antivirais/análise , Antígenos Virais/análise , Reações Cruzadas , Glicoproteínas/análise , Soros Imunes/isolamento & purificação , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Coelhos , Proteínas do Envelope Viral/análise
12.
Bioorg Khim ; 9(2): 276-9, 1983 Feb.
Artigo em Russo | MEDLINE | ID: mdl-6679771

RESUMO

RNA of a flavivirus-tick-borne encephalitis virus (Far-East, type 1, strain Sofin) was subjected to reverse transcription and the DNA copy was transformed into double-stranded DNA by action of E. coli DNA-polymerase (Klenow's fragment) without primer. The hairpin structures were removed by S1 nuclease. Oligo-dC ends were attached to ds-cDNA thus obtained, and this DNA was annealed with pBR322 plasmid cut by PstI and equipped with oligo-dG termini. The recombinant plasmids were cloned in E. coli HB101. Of the 360 TcrAps clones obtained, 187 clones efficiently hybridized with partially degraded 32P-RNA of TBE virus. The sequence of the insert of one of the clones was determined by the Maxam-Gilbert method. The 720 b.p. sequence is translatable into an amino acid sequence without interruption. Nearby the 3'-terminus of the insert, the sequence ACACAGG is present which is homologous with that found in RNA of the flavivirus West Nile.


Assuntos
Clonagem Molecular , DNA Viral/genética , Vírus da Encefalite Transmitidos por Carrapatos/genética , Genes Virais , Sequência de Bases
14.
Vopr Virusol ; (3): 359-66, 1978.
Artigo em Russo | MEDLINE | ID: mdl-211734

RESUMO

Electron microscopic examinations of brains of white mice inoculated with the An 750 strain isolated for the first time from adult mosquitoes and with the prototype LB strain of Powassan virus were carried out. The method of combination of light and electron microscopy used in the study permitted to compare ultrastructural changes in one cell with the results of light microscopy. Sizes of virions and their localizations in the brain cells were determined. Virus particles were found in large and small neurons as well as in glial elements. Subcellular changes in neurons associated with virus multiplication are described. The causes of differences in sizes of virions measured in ultrathin sections are discussed.


Assuntos
Encéfalo/microbiologia , Vírus da Encefalite Transmitidos por Carrapatos/ultraestrutura , Encefalite Transmitida por Carrapatos/microbiologia , Animais , Encéfalo/patologia , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Encefalite Transmitida por Carrapatos/patologia , Camundongos , Microscopia Eletrônica , U.R.S.S. , Vírion/ultraestrutura , Replicação Viral
16.
Intervirology ; 8(5): 294-308, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-18425

RESUMO

Similar physicochemical characteristics were found with strains of Crimean hemorrhagic fever (CHF) and Congo viruses. The particle size, sedimentation coefficient, buoyant density, weight of the particles as well as morphology and morphogenesis of these viruses were similar to those of other members of the Bunyaviridae family. Data are presented on reproduction of CHF virus in cell cultures and on the inner structure of its virion.


Assuntos
Arbovírus/ultraestrutura , Vírus da Febre Hemorrágica da Crimeia-Congo/ultraestrutura , Centrifugação com Gradiente de Concentração , Clorofórmio/farmacologia , Efeito Citopatogênico Viral , Detergentes/farmacologia , Éter/farmacologia , Vírus da Febre Hemorrágica da Crimeia-Congo/efeitos dos fármacos , Vírus da Febre Hemorrágica da Crimeia-Congo/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Temperatura , Raios Ultravioleta
18.
Arch Virol ; 50(1-2): 169-72, 1976.
Artigo em Inglês | MEDLINE | ID: mdl-816333

RESUMO

Morphological characteristics of Crimean Hemorrhagic Fever Virus indicate that it is closely related to the Bunyaviridae family. However, there are some features (e.g. formation of crystal-like patterns in infected cells) demonstrating differences to the other known Bunyaviridae.


Assuntos
Arbovírus/ultraestrutura , Vírus da Febre Hemorrágica da Crimeia-Congo/ultraestrutura , Animais , Encéfalo/microbiologia , Vírus Bunyamwera/crescimento & desenvolvimento , Cristalografia , Técnicas de Cultura , Citoplasma/microbiologia , Complexo de Golgi/microbiologia , Vírus da Febre Hemorrágica da Crimeia-Congo/crescimento & desenvolvimento , Corpos de Inclusão Viral , Camundongos , Morfogênese , Replicação Viral
20.
Age Ageing ; 4(3): 142-7, 1975 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1211299

RESUMO

A point prevalence survey, using a questionnaire, was performed in three general hospitals to investigate the problem of elderly patients blocking acute-hospital beds. A total of 1010 occupied general beds were surveyed and all patients, over the age of 60 years, who had been in hospital more than four weeks, and who, in the opinion of medical and nursing staff, were no longer in need of the facilities of a general hospital, were investigated. Forty-eight patients (4.8 per cent of the total) were found to be genuinely in bed inappropriate to their needs. Rehabilitation, together with assessment of these patients, appeared disorganized and lacked consistency, and decisions regarding suitable 'disposal' appeared to be made without sufficient consultation and conformed to no detectable pattern. The main reason for the continuing bed occupancy of the patients was the length of the waiting lists for alternative residential accommodation and the main single medical factor preventing discharge home or to a hostel was the problem of mobility. By interviewing staff and patients and scrutinizing the questionnaires, it was found that 23 patients (48 per cent) were only suitable for transfer to a long-stay hospital. Of these, however, 15 (31 per cent) could be placed in specialized accommodation if some degree of nursing care, at present not available, was provided.


Assuntos
Geriatria , Tempo de Internação , Idoso , Inglaterra , Feminino , Hospitais Gerais , Humanos , Masculino , Pessoa de Meia-Idade
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