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1.
Phys Rev Lett ; 105(1): 018901; author reply 018902, 2010 Jul 02.
Article in English | MEDLINE | ID: mdl-20867486
4.
Article in Russian | MEDLINE | ID: mdl-11236493

ABSTRACT

Serological study of 788 blood sera, taken from residents of the Moscow region was conducted using antigens of microorganisms of the genera Rickettsia and Bartonella. The first group under examination consisted of 355 patients with diagnosed diseases of nonreckettsial nature. The second group includes 433 healthy adults working at a meat processing and packing factory. The main method used for sera survey was the indirect immunofluorescence test. In the sera taken from the first group of subjects specific antibodies to R. prowazekii, R. typhi, B. quintana, B. henselae antigens were detected in 2.3%, 5.1%, 4.0% and 2.9% of serum samples respectively. In the serum samples taken from the second group the proportion of antibodies to R. prowazekii, R. typhi, B. quintana, B. henselae antigens was different: 0.5%, 3.3%, 1.7% and 4.0% respectively. In total, specific antibodies to R. typhi and B. henselae prevailed over specific antibodies to R. prowazekii and B. quintana twofold.


Subject(s)
Antibodies, Bacterial/blood , Bartonella/isolation & purification , Rickettsia/isolation & purification , Adult , Bartonella/immunology , Fluorescent Antibody Technique, Indirect , Humans , Moscow , Rickettsia/immunology
5.
Voen Med Zh ; 320(9): 59-65, 96, 1999 Sep.
Article in Russian | MEDLINE | ID: mdl-10575953

ABSTRACT

Difficulties in the clinical diagnosis of rickettsiosis and related illnesses made it necessary to develop and improve its methods (immunoferment analysis, nondirect methods of fluorescent antibodies and polimerase chain reaction). Detailed recommendations for diagnosis of Q-fever by the level and growth of antibodies of IgG and IgA subclasses.


Subject(s)
Rickettsia Infections/diagnosis , Animals , Antibodies, Bacterial/blood , Diagnosis, Differential , Humans , Immunologic Tests/methods , Rickettsia/immunology , Rickettsia/isolation & purification , Rickettsia Infections/complications , Rickettsia Infections/microbiology
6.
Article in Russian | MEDLINE | ID: mdl-10356738

ABSTRACT

The analysis of the results of prolonged observations on the prophylactic immunization of employees working with R. prowazekii is presented. The necessity of the differentiated approach to the determination of the immunization schedule and the choice of vaccine is shown. The presence of specific antibodies (Ab) and the level of their titers have been found to be related to the degree of anti-infectious protection. The following characteristics indicate the presence of profound immunological transformation in vaccinees: complement-fixing Ab in titers 1:10 and more and/or immunofluorescent Ab in titers not below 1:180, Ab to protein in the hemagglutination test in titers not below 1:1000. These specific Ab and the level of their titers can be registered after the second injection of live combined typhus vaccine E and the third injection of chemical typhus vaccine. Cases of laboratory infection and their relationship to the character of immunization and the intensity of contacts with R. prowazekii virulent strains are discussed. Attention is drawn to the strict observance of professional safety rules.


Subject(s)
Occupational Exposure/prevention & control , Research Personnel , Rickettsia prowazekii/immunology , Rickettsial Vaccines/immunology , Typhus, Epidemic Louse-Borne/prevention & control , Vaccination/methods , Academies and Institutes , Antibodies, Bacterial/blood , Antibody Specificity , Humans , Immunization Schedule , Immunization, Secondary , Moscow , Rickettsia prowazekii/pathogenicity , Time Factors , Vaccines, Attenuated/immunology , Vaccines, Combined/immunology , Vaccines, Synthetic/immunology
7.
Am J Trop Med Hyg ; 55(6): 685-92, 1996 Dec.
Article in English | MEDLINE | ID: mdl-9025699

ABSTRACT

Restriction fragment length polymorphism (RFLP) analysis of polymerase chain reaction-amplified gene fragments was used to characterize 24 isolates of spotted fever group rickettsiae previously identified as Rickettsia sibirica from their serologic properties. These strains were obtained in Russia between 1946 and 1991 from humans and different species of Ixodid ticks. The RFLP analysis was performed using amplified DNA products obtained with a genus-specific primer pair derived from the R. prowazekii citrate synthase gene and two group-specific primer pairs from the R. rickettsii 190-kD and 120-kD surface protein antigen genes followed by Alu I, Pst I, and Rsa I restriction endonuclease digestions. Although some differences were detected in biological characteristics among the examined strains, only a single R. sibirica genotype was found with these molecular tools of identification.


Subject(s)
Arachnid Vectors/microbiology , Polymorphism, Restriction Fragment Length , Rickettsia Infections/microbiology , Rickettsia/genetics , Ticks/microbiology , Animals , Chick Embryo , Chlorocebus aethiops , DNA, Bacterial/analysis , Genome, Viral , Guinea Pigs , Humans , Male , Polymerase Chain Reaction , Rickettsia/isolation & purification , Rickettsia/pathogenicity , Rickettsia Infections/transmission , Russia , Vero Cells , Virulence
8.
J Clin Microbiol ; 33(11): 3022-4, 1995 Nov.
Article in English | MEDLINE | ID: mdl-8576365

ABSTRACT

Pulsed-field gel electrophoresis of SmaI-, EagI-, and BssHII-digested DNA was used to perform restriction fragment length polymorphism analysis of Rickettsia akari strains isolated from humans, rodents, and mites in the United States and Ukraine. Although some differences in biological and serological characteristics were present between strains, the genomic studies demonstrated a high degree of intraspecies homogeneity of R. akari isolates. Our results confirm the value of pulsed-field gel electrophoresis-restriction fragment length polymorphism analysis for the identification of species of rickettsiae.


Subject(s)
Genome, Bacterial , Polymorphism, Restriction Fragment Length , Rickettsia/genetics , Animals , Deoxyribonucleases, Type II Site-Specific , Electrophoresis, Gel, Pulsed-Field , Humans , Mites/microbiology , Rickettsia/classification , Rickettsia Infections/epidemiology , Rickettsia Infections/microbiology , Rodentia/microbiology , Serotyping , Ukraine/epidemiology , United States/epidemiology
9.
J Clin Microbiol ; 33(10): 2738-44, 1995 Oct.
Article in English | MEDLINE | ID: mdl-8567916

ABSTRACT

Strain S, a spotted fever group (SFG) rickettsia isolated from Rhipicephalus sanguineus ticks collected in Armenia, was identified. Microimmunofluorescence, sodium dodecyl sulfate-polyacrylamide gel protein electrophoresis and Western immunoblotting, PCR and then restriction fragment length polymorphism analysis, pulsed-field gel electrophoresis, and 16S rRNA gene sequencing were used to compare strain S with reference isolates. Strain S was found to possess proteinic, antigenic, and genomic patterns which were unique among SFG rickettsiae. Strain S is characterized by its high degree of pathogenicity for experimental animals, but its role as a potential human pathogen should be determined. The role of R. sanguineus ticks in the epidemiology of SFG rickettsiae is discussed.


Subject(s)
Rickettsia/classification , Ticks/microbiology , Animals , Armenia , Bacterial Proteins/analysis , Bacterial Typing Techniques , DNA, Bacterial , DNA, Ribosomal/genetics , Electrophoresis, Gel, Pulsed-Field , Immunoblotting , Molecular Sequence Data , Polymorphism, Restriction Fragment Length , RNA, Ribosomal, 16S/genetics , Rickettsia/chemistry , Rickettsia/genetics , Rickettsia Infections/microbiology , Sequence Analysis, DNA , Serotyping
10.
Acta Virol ; 39(4): 205-209, 1995 Sep.
Article in English | MEDLINE | ID: mdl-8825301

ABSTRACT

The growth of mildly pathogenic strain E, its virulent revertant EVir, and prototype virulent strain Breinl of Rickettsia prowazekii in peritoneal macrophage cultures of outbread white rats (WR) was evaluated by light microscopy and bioassay in chick embryos (CE). Macrophage cultures infected with strain E were characteristic by limited number of infected cells, poor or moderate accumulation of rickettsiae in individual cells, poor or nil spread of infectious process during first 7 days of infection, and the death of rickettsiae in cultures as determined by the bioassay in CE. Moreover, rickettsiae were not determined in 20.7% of infected macrophage cultures by either microscopic or bioassay methods. In contrast, the growth of virulent strains EVir and Breinl was characteristic by higher proportion of infected cells, considerable accumulation of rickettsiae, and intensive spread of infectious process within 5-7 days post infection (p.i.). However, the intensity of infectious process in macrophage cultures was less expressed with strain EVir than with strain Breinl.


Subject(s)
Macrophages, Peritoneal/microbiology , Rickettsia prowazekii/growth & development , Animals , Cells, Cultured , Chick Embryo , Macrophages, Peritoneal/metabolism , Male , Rats , Rickettsia prowazekii/pathogenicity , Time Factors , Virulence
11.
Eur J Epidemiol ; 11(4): 383-7, 1995 Aug.
Article in English | MEDLINE | ID: mdl-8549703

ABSTRACT

Astrakhan fever is a new spotted fever group (SFG) rickettsiosis. Sera of patients with Astrakhan fever have been examined by microimmunofluorescence and western immunoblotting to determine the serologic responses to the Astrakhan strain and to R. conorii M-1 strain and the Israelian isolate of SFG rickettsiae. The serologic response to specific rickettsial agent and to Israelian isolate has been found to be similar, but was different of that to R. conorii. Immunoglobulin G (IgG) and IgM antibodies were detected in most sera and were directed against the lipopolysaccharide. Only one of tested sera contained IgG antibodies which also recognized high molecular weight proteins.


Subject(s)
Antibodies, Bacterial/analysis , Boutonneuse Fever/immunology , Immunoglobulin G/analysis , Immunoglobulin M/analysis , Rickettsia/immunology , Boutonneuse Fever/epidemiology , Electrophoresis, Polyacrylamide Gel , Fluorescent Antibody Technique , Humans , Immunoblotting , Israel/epidemiology , Rickettsia Infections/epidemiology , Rickettsia Infections/immunology , Russia/epidemiology
12.
Mol Gen Mikrobiol Virusol ; (6): 29-33, 1994.
Article in English | MEDLINE | ID: mdl-7739594

ABSTRACT

Five strains of Rickettsia prowazekii different in origin, biological and genetic properties were compared in protein and LPS patterns by the polyacrylamide gel electrophoresis and in antigenic properties by immunoblotting with specific sera of infected white mice. Three virulent strains Breinl, G and Katsinjan had identical protein patterns and differed from isogenic pair of strains E and EVir in the electrophoretic properties of 29-30 kDa proteins. Silver-strained LPS patterns were different in five compared strains. Strain G and strain Katsinjan had the longest O-chaines of LPS. Polyclonal mouse antisera contained specific antibodies which mainly directed against LPS and 25-60 kDa proteins. Strains E and EVir were identical in all performed immunoblotting reactions and separated from three virulent strains. Out of virulent strains, whole cell antigen of strain Katsinjan and LPS antigen of strain G had different reactions in comparison with correspondent antigen of the standard strain Breinl.


Subject(s)
Antigens, Bacterial/immunology , Immune Sera , Rickettsia prowazekii/immunology , Animals , Antigens, Bacterial/genetics , Blotting, Western , Electrophoresis, Polyacrylamide Gel , Mice , Rickettsia prowazekii/pathogenicity , Virulence/immunology
13.
Acta Virol ; 38(2): 65-70, 1994 Apr.
Article in English | MEDLINE | ID: mdl-7976865

ABSTRACT

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.


Subject(s)
DNA, Bacterial/genetics , Rickettsia/genetics , Animals , Antigens, Bacterial/genetics , Bacterial Typing Techniques , Citrate (si)-Synthase/genetics , DNA Probes , Genes, Bacterial , Genotype , Humans , Rickettsia/classification , Rickettsia/isolation & purification , Rickettsia prowazekii/enzymology , Rickettsia prowazekii/genetics , Rickettsia prowazekii/immunology , Species Specificity
14.
Acta Virol ; 37(6): 475-83, 1993 Dec.
Article in English | MEDLINE | ID: mdl-7912040

ABSTRACT

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.


Subject(s)
Rickettsia Infections/microbiology , Rickettsia/classification , Animals , Citrate (si)-Synthase/genetics , Cross Reactions , DNA, Bacterial/genetics , Dermacentor/microbiology , Guinea Pigs , Humans , Immune Sera/immunology , Male , Mice , Polymorphism, Restriction Fragment Length , Rats , Rickettsia/genetics , Rickettsia/isolation & purification , Rickettsia/pathogenicity , Serotyping , Ukraine , Virulence
15.
J Clin Microbiol ; 31(10): 2625-33, 1993 Oct.
Article in English | MEDLINE | ID: mdl-7902843

ABSTRACT

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), restriction fragment length polymorphism of polymerase chain reaction-amplified genes (RFLP-PCR), and pulsed-field gel electrophoresis (PFGE) were used to identify 25 isolates of spotted fever group rickettsia collected in the former USSR. Six Rickettsia akari isolates which were identical to the MK reference strain from the American Type Culture Collection were found. Also, 14 isolates were found to be Rickettsia sibirica and identical to reference strain 246. Two of three isolates previously considered as atypical, low-pathogenic strains of R. sibirica, were found to be strains of Rickettsia slovaca. The third, strain S, was similar in its RFLP-PCR profile to "R. africae" sp. nov. (proposed name for a rickettsia pathogenic for human beings in southern Africa) but in its SDS-PAGE and PFGE profiles was unique among spotted fever group rickettsiae. Strain M-1 was confirmed as a genetic variant of Rickettsia conorii. The Astrachan isolate, the causative agent of a tick-bite rickettsiosis at the North of the Caspian Sea, showed a previously described RFLP-PCR profile identical to that of the Israeli tick typhus rickettsia, but its SDS-PAGE and PFGE profiles different from those of the other strains tested.


Subject(s)
Bacterial Proteins/analysis , Boutonneuse Fever/microbiology , DNA, Bacterial/analysis , Rickettsia Infections/microbiology , Rickettsia/classification , Animals , Electrophoresis, Gel, Pulsed-Field , Electrophoresis, Polyacrylamide Gel , Humans , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Rickettsia/chemistry , Rickettsia/genetics , Russia
16.
Mol Gen Mikrobiol Virusol ; (4): 15-9, 1993.
Article in Russian | MEDLINE | ID: mdl-8103913

ABSTRACT

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).


Subject(s)
Rickettsia/genetics , DNA Probes , Genes, Bacterial , Genotype , Nucleic Acid Hybridization , Polymorphism, Restriction Fragment Length , Species Specificity
17.
Acta Virol ; 36(1): 52-6, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1350172

ABSTRACT

The protein antigens of two distinct lines of genetically related strains, namely the nonpathogenic strain E and its virulent revertant EVir and of the standard virulent strain Breinl were compared in SDS-PAGE and immunoblot assay using typhus patient sera and immune rabbit sera. No differences in the polypeptide pattern as detected in SDS-PAGE were found between strain E and EVir; the Breinl strain differed in a 30 kD protein. The high immunogenicity of the protein antigens of E, EVir and Breinl strains was demonstrated by immunoblot assay with human sera, which did not show any differences between the strains studied. Immunoblot analysis with immune rabbit sera to the strain E, EVir, and Breinl showed differences in immunological response to the 70 kD and 60 kD polypeptides of low virulent strain E and those of virulent strains EVir and Breinl.


Subject(s)
Bacterial Proteins/immunology , Rickettsia prowazekii/immunology , Animals , Antigens, Bacterial/genetics , Antigens, Bacterial/immunology , Bacterial Proteins/genetics , Chick Embryo , Electrophoresis, Polyacrylamide Gel , Immunoblotting , Rabbits , Rickettsia prowazekii/genetics , Rickettsia prowazekii/pathogenicity , Typhus, Epidemic Louse-Borne/immunology , Typhus, Epidemic Louse-Borne/microbiology , Virulence
18.
Acta Virol ; 35(6): 526-30, 1991 Nov.
Article in English | MEDLINE | ID: mdl-1687635

ABSTRACT

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.


Subject(s)
DNA, Bacterial/genetics , Rickettsia/genetics , Polymorphism, Restriction Fragment Length , Species Specificity , Typhus, Epidemic Louse-Borne/microbiology
19.
Zh Mikrobiol Epidemiol Immunobiol ; (4): 69-71, 1991 Apr.
Article in Russian | MEDLINE | ID: mdl-1831951

ABSTRACT

Starting from 1978, noncontagious febrile diseases of unclear etiology, accompanied by pronounced headache, roseolous-papular eruptions, prolonged convalescence period, are registered in May-September in Astrakhan Province. These diseases can be effectively treated with chrolamphenicol. In 11 out of 12 sera obtained from such patients the complement fixation test with the antigens of rickettsiae causing tick-borne spotted fever, epidemic typhus, as well as Coxiella burnetii antigen, revealed the presence of antibodies (in 8 sera) only to the antigens of rickettsiae causing tick-borne spotted fever (R. akari, R. conorii, R. sibirica), or the titers of antibodies to these antigens were greater (1 serum), equal and lower (2 sera) in comparison with those of the antigens of rickettsiae causing epidemic typhus. The dynamics and values of antibody titers in 7 patients with the antigens of three rickettsial species of the tick-transmitted biotype indicated that the disease was related to tick-borne spotted fever.


Subject(s)
Rickettsia Infections/diagnosis , Antibodies, Bacterial/blood , Antibody Specificity , Complement Fixation Tests , Humans , Rickettsia/immunology , Rickettsia Infections/epidemiology , Russia/epidemiology , Seroepidemiologic Studies
20.
Acta Virol ; 34(2): 171-7, 1990 Apr.
Article in English | MEDLINE | ID: mdl-1975978

ABSTRACT

Cultural properties and the capacity for persistence were studied in spontaneous erythromycin-resistant (E errSM), in induced erythromycin-resistant (E errI) mutants and in a virulent revertant (E Vir) of the vaccine strain E, as compared with parent vaccine strain E and standard virulent strain Breinl of Rickettsia prowazekii. Cultural properties of the strains were found to differ in passages in chick embryos (CE) and cultures of FL cells. Multiplication indices in CE of mutant E errI were significantly lower than those of other strains (E, E errSM, E Vir, Breinl). The multiplication rate in FL cells was found to be high in strains E errSM, Breinl, E Vir, being much lower in strains E errI and E. The capacity of the virulent revertant E Vir to persist in cotton rat (CR) was higher as compared with that of standard strain Breinl and significantly higher than that of the parent strain E. Low level carrier state of rickettsia was registered in CR infected with the mutant E errI.


Subject(s)
Rickettsia prowazekii/growth & development , Animals , Cells, Cultured , Chick Embryo , Drug Resistance, Microbial/genetics , Male , Mutation , Rats , Rickettsia prowazekii/genetics , Virulence , Virus Replication
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