Rydkina Eb

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

Demkin Vv

Kurchatov Institute

Ignatovich Vf

Gamalei Institute of Epidemiology and Microbiology

Balaeva Nm

Genig Va

Artem'ev Mi

Balayeva Nm

Centre National de la Recherche Scientifique

Artemiev Mi

Gamalei Institute of Epidemiology and Microbiology

Kokorin In

Reshetnikova Ta

Likhoded Ly

Cooperative Institutions

Gamalei Institute of Epidemiology and Microbiology

Centre National de la Recherche Scientifique

Saint Petersburg Pasteur Institute

University of Arizona

Aix-Marseille Université

Méditerranée Infection Foundation

Institut de Recherche pour le Développement

Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes

Institut de Neurobiologie de la Méditerranée

Inserm

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

[Use of the immunofluorescence reaction for evaluating the immunological transformation in those inoculated with a chemical typhus vaccine].

PubMed (1985)

Rydkina Eb Shirokova Em Balaeva Nm Kokorin In Nikol'skaia Vn

The results of the serological examination of persons immunized with chemical typhus vaccine (CTV) are presented. The examination was carried out by means of the complement fixation test (CFT), the passive hemagglutination test (PHAT), the toxin neutralization test (TNT) and the immunofluorescence test (IFT). The acetone-fixed live culture of Rickettsia prowazekii, strain Breinl, served as antigen in IFT. If persons immunized with CTV showed positive titers in CFT, TNT and PHAT, the results of IFT were highly correlated with the CFT titers. In 6-12 months after immunization with CTV the titers of CFT, TNT and PHAT became negative, while the IFT titers remained positive for several subsequent years.

Complement fixation test

Immunofluorescence

Antibody titer

Rickettsia prowazekii

Source

Cite

Citations (0)

Restriction fragment length polymorphism of the DNA of typhus group rickettsiae.

PubMed (1991)

Artemiev Mi Ignatovich Vf Rydkina Eb Lichoded Lj Balayeva Nm

The DNA of 10 strains of Rickettsia prowazekii, 5 strains of Rickettsia typhi and 1 strain of Rickettsia canada was investigated by restriction fragment length polymorphism analysis. Interspecies differences were characterized by a great number of noncomigrating bands. Using the endonuclease HindIII and PstI fragments comigration as a quantitative criterion, genetic similarity coefficient was calculated for the pair Rickettsia prowazekii/Rickettsia typhi-32.0%, for Rickettsia prowazekii/Rickettsia canada-22.7%, and for Rickettsia typhi/Rickettsia canada-23.5%. Intraspecies differences expressed are very subtle and concern 1-2 noncomigrating fragments. The investigated strains of Rickettsia prowazekii and Rickettsia typhi can be divided into 2 groups without any correlation to the source and period of isolation, or to strain passage history.

Rickettsia prowazekii

Rickettsia typhi

Rickettsiaceae

Source

Cite

Citations (2)

[Genotypic characteristics of Rickettsia sibirica strains].

PubMed (1993)

Balaeva Nm Artem'ev Mi Ignatovich Vf Likhoded LIa Genig Va

Six Rickettsia sibirica strains isolated in Siberia and Far East (Primorje) from various sources (patient, ticks D. nuttali, D. silvarum, H. concinna) at different time (1940-1980) were studied by the RFLP and DNA probe hybridization techniques. All studied strains were found to have the identical profiles of migrating fragments in restrictograms got by using a set of endonucleases (EcoRI, PstI, PvuII, Bg1I, XbaI, HindIII, MspI) and similar zones of hybridization with a DNA probe derived from Rickettsia prowazekii DNA. The obtained data point to a close similarity between the genomes of investigated Rickettsia sibirica strains. Long-term isolation of the genetically similar Rickettsia sibirica strains testifies to their constant circulation, thus apparently determining the stability of epidemiologic manifestation of tick-borne typhus fever of Northern Asia in the central part of its area (Siberia, Far East).

Rickettsia prowazekii

PstI

Source

Cite

Citations (0)

[The rickettsial genome studied by DNA restriction analysis].

PubMed (1990)

Rydkina Eb Artem'ev Mi Balaeva Nm Ignatovich Vf Demkin Vv

The restriction analysis of 6 Rickettsia prowazekii strains with the use of 8 restrictases (Cfr13I, EcoRI, HindIII, MSpI, MvaI, PstI, XhoI, BamHI) has been carried out. In the presence of considerable homology in the restriction pictures of DNA in these strains some differences in 1-2 fragments within the range of 8,000-20,000 nucleotide pairs have been established. The strains under study have been divided into two groups according to the character of differences in their restrictograms: the group of virulent typing strain Breinl (Breinl, G. Anan'ev) and the group of strain E with low pathogenicity (E, EVir, Katsinian). Differences in the restrictograms of DNA do not correlate with the virulence of R. prowazekii strains and the areas of their isolation.

XhoI

PstI

Rickettsia prowazekii

Ribotyping

Restriction fragment

Source

Cite

Citations (1)

Genotypic characterization of rickettsiae by DNA probes generated from Rickettsia prowazekii DNA.

PubMed (1994)

Demkin Vv Rydkina Eb Likhoded Ly Ignatovich Vf Genig Va

Southern blot analysis of HindIII-cleaved rickettsial DNA was used for genotypic characterization of the typhus group (TG) species (R. prowazekii, R. typhi, R. canada) and a few species of the spotted fever group (SFG) rickettsiae (R. sibirica, R. conorii, R. akari). Four different DNA probes were employed. PBH11 and PBH13 probes were morphospecific HindIII fragments of R. prowazekii DNA. MW218 probe contained the gene for 51 K antigen and MW264 probe contained the citrate synthase gene of R. prowazekii. All the probes hybridized with the tested TG and SFG rickettsial DNAs, forming from 1 to 5 bands, but they did not with R. tsutsugamushi or C. burnetii DNAs. All the probes demonstrated specific hybridization patterns with TG species and R. akari. PBH11, PBH13 and MW264 probes clearly distinguished R. sibirica and R. conorii from the other tested rickettsiae, but not from each other. However, these two species differed slightly with MW218 probe. Several strains of each species were analyzed in this way and except for strains of R. conorii identical intraspecies patterns were obtained. These data lead us to consider the obtained hybridization patterns as criteria for genotypic identification.

Rickettsia prowazekii

Rickettsia conorii

Hybridization probe

Southern blot

Rickettsiaceae

Source

Cite

Citations (2)

[Determination of Ehrlichia genome size by pulse gel electrophoresis].

PubMed (2000)

Rydkina Eb Roux Tarasevich Didier Raoult

Ehrlichia infections are more and more common in the USA and Europe. The genetics and genome organization of Ehrlichia are little studied due to great difficulties in cultivating these bacteria. Pulse gel electrophoresis was first used to determine the sizes of a genome of 3 representatives of the genus Ehrlichia. The sizes of a genome was established for E. sennetsu (881 kb), for E. risticii (867 kb), E. chaffeensis (1,236 kb).

Ehrlichia chaffeensis

Genome size

Source

Cite

Citations (0)

Genotypic and biological characteristics of non-identified strain of spotted fever group rickettsiae isolated in Crimea.

PubMed (1993)

Balayeva Nm Demkin Vv Rydkina Eb Ignatovich Vf Artemiev Mi

A strain of rickettsiae, designated Crimea-108, was isolated from ticks Dermacentor marginatus in the Crimea in 1977. Its immunobiological characteristics involve low pathogenicity for experimental animals, moderate infectivity for chick embryos, and antigenic relatedness to spotted fever group (SFG) rickettsiae (R. sibirica, R. conorii, R. akari), especially to R. sibirica. The genotypic characterization of the strain Crimea-108 was carried out in comparison with SFG and typhus group rickettsiae by using restriction fragment length polymorphism (RFLP) analysis and DNA-probe hybridization. The marked similarity was detected between DNA restriction patterns of the strains Crimea-108, R. sibirica and R. conorii, but each of them besides comigrating fragments had specific ones. Genotypic analysis of the strain Crimea-108, the SFG and typhus group rickettsiae by three independent DNA probes, based on R. prowazekii DNA, gave unique hybridization patterns for the Crimea-108 strain with all probes. The obtained data show that the Crimea-108 isolate does not belong to the species of R. sibirica, R. conorii, R. akari. The strain Crimea-108 is a novel strain of SFG rickettsiae for the Crimea region.

Rickettsia conorii

Strain (injury)

Rickettsiaceae

Source

Cite

Citations (5)

[The library of Rickettsia prowazekii genes].

PubMed (1987)

Artem'ev Mi Rydkina Eb Balaeva Nm

The DNA of Rickettsia provazekii strain E was cleaved by PstI restriction endonuclease under the conditions of partial restriction. The fragments were inserted into the PstI site of pBR325 and cloned in this plasmid. E. coli strain HB101 was used as a recipient for cloning. 880 clones sensitive to ampicillin and resistant to tetracycline were selected from 5120 transformants. The cloning of rickettsial DNA has been confirmed by the blot hybridization technique. Analysis of individual and net probes of the hybrid DNA by gel electrophoresis makes it possible to conclude that 90% of the selected clones harbour hybrid plasmids, the size of the cloned fragments rangers from 0.9 to 10.4 Kb, the obtained library of clones contains 70% of the whole genome of Rickettsia provazekii.

Rickettsia prowazekii

PstI

Southern blot

Cloning (programming)

Source

Cite

Citations (0)

Persistence of Rickettsia prowazekii with different initial biological properties in infected cotton rats.

PubMed (1983)

Ignatovich Vf Barkhatova Oi Rydkina Eb

Evidence has been obtained indicating the association of certain biological properties of Rickettsia prowazekii with their capacity for persistence. Highly virulent rickettsial cultures inducing increased levels of complement-fixing antibodies were shown to cause a high percentage of rickettsial carriers in infected cotton rats. Within an interval of 133-189 days after inoculation with the virulent Breinl strain, rickettsial carrier-state was still demonstrable in 20% of the animals. The vaccine strain E of R. prowazekii had a low capacity for persistence in cotton rats, because 64 days after inoculation all animals were found free of rickettsiae.

Rickettsia prowazekii

Persistence (discontinuity)

Strain (injury)

Source

Cite

Citations (6)

[Characteristics of DNA restriction fragment length polymorphisms of C. burnetti strains, isolated from areas of Russia].

PubMed (1993)

Demkin Vv Tokarevich Nk Rydkina Eb Kuzina Va Kartseva Na

The structural heterogeneity in Coxiella burnetii chromosomal DNA isolated in the European part of Russia from people, agricultural animals, and ticks has been studied. It is compared with the one of the European strains Henzerling and M44, the only genetically characterized strains up to date. The digestion of the total DNA by the restriction endonucleases BamHI, PstI, XhoI resulted in obtaining two types of restriction patterns. The ones for Henzerling and M44 differed from the restriction patterns of the Russian strains, while the latter proved to be identical. The obtained data are in proof of genetical homogeneity in the Russian group of strains. The group is different from the genomic group including Henzerling and M44. The fact is in proof of the genetical heterogeneity of the European population of coxiellae.

XhoI

genomic DNA

Restriction site

PstI

Source

Cite

Citations (0)