PubMed Health⌕ Search

Biomedical subjects

E A Tkachenko

Publications and source records attributed to E A Tkachenko.

At least 19 recordsLinked to original sources

[Nervous system involvement in hemorrhagic fever with renal syndrome].

The authors of the article describe two cases of hemorrhagic fever with renal syndrome (HFRS) with prevalence of signs of nervous system involvement. The first case was a 40-year-old woman with moderate HFRS, who developed Guillain-Barre syndrome of axonal-demyelinating polyneuropathy. An important observation was the absence of hemorrhagic or renal syndrome; combined therapy including plasmapheresis was successful. The second case demonstrated polymorphism of HFRS clinical manifestations with prevalence of neurological symptoms, which consisted in encephalopathy and no renal failure signs; hemorrhagic syndrome was moderate. In both cases the diagnosis was confirmed by elevated titer of antibodies to HFRS virus, belonging to the group of hantaviruses.

Adolescent↗

[Analysis of the primary structure of hantavirus RNA, detected in organs of patients that died from HFKS in the Republic of Bashkortostan].

Fragments of the minor S and middle M segments of Hantavirus genome RNA were isolated by reverse transcription-polymerase chain reaction (RT-PCR) from the organs of patients who died from hemorrhagic fever with the renal syndrome (HFRS) during an epidemic outbreak of this infection in the Bashkortostan Republic in 1997-1998. The sizes of the resultant PCR fragments were 317 p. n. for S segment and 416 p. n. for M segment. Their primary structures (GENBANK registration numbers AJ133581 and AJ133582) were determined and they were compared with the nucleotide sequences of the respective genome sites of Hantavirus strain CG1820/Ufa-83 isolated from Clethrionomys in Bashkortostan in 1983. The homologies of nucleotide sequences of the corresponding sites of S and M segments of RNA isolate of 1997 and CG1820/Ufa-83 were 87.7 and 96.6%, respectively. The authors discuss the probability of circulation of hantaviruses differing by individual features of primary structure of genome RNA in Bashkortostan.

Amino Acid Sequence↗

Serological evidence of Hantaan virus in Slovakia during 1989-1991.

Nephropathia epidemica was supposed to be an European form of haemorrhagic fever with renal syndrome (HFRS). However, in 1989-1991 we found serological evidence of infection with Hantaan virus in patients' sera from Slovakia. Higher titers of antibodies against Hantaan virus were detected in sera of 6 out of 75 patients with febrile disease, renal failure and clinical diagnosis of HFRS. The higher titers of antibodies against Puumala virus were detected in sera of 6 out of 75 patients. Serologic differentiation between Hantaan and Puumala infection in patients was based on the detection of higher antibody titers (4-fold or greater differences).

Adolescent↗

Anti-hantavirus antibodies in human sera in Czechoslovakia.

By indirect immunofluorescence using antigens of hantavirus Hantaan and CG 18-20 on Vero E6 cells were examined 5,827 samples of sera from 5,299 probands of Czechoslovakia. In 49 persons (0.94%) were found antibodies of titres 1:32 and higher. Two groups of elderly farm workers showed a cluster of positive individuals amounting to 9.9% and 29.4% respectively. The ratio of positivities in some other, randomly and specifically selected groups was deep below 1%. The partial results for the group of farmers were confirmed by RIA test. Occasionally antibodies only to one of the hantavirus serotypes, at other time, to both were found. The authors discuss the findings of antibodies of the two serotypes in humans as related to the evidenced existence of two hantavirus antigen serotypes in animals.

Adolescent↗

[The intensity of the immune response to the hemorrhagic fever with renal syndrome virus among different population groups of Bashkortostan].

For the first time the natural immune stratum to hemorrhagic fever with the renal syndrome (HFRS) among the population of all regions of Bashkiria, a large territory with the highest morbidity level in this infection in the USSR, was studied. 9,176 persons over 15 years of age were examined by radioimmune techniques. Analysis of the immune structure of the population revealed that the share of immune males was higher than that of immune females, but the difference was less than the difference between males and females among the registered HFRS patients. Among children immune persons were almost completely absent. The immune stratum increased rather slowly among persons under 40 years, and only from this age the considerable increase of the immune stratum was observed (up to 16.2%). High risk groups included persons of such professions as forestry workers, truck and tractor drivers, oil workers and prospectors, livestock breeders, builders. These data may be used for the formation of groups to be vaccinated against HFRS in foci with different degrees of activity. Before vaccination the correction of groups to be vaccinated in a given region should be carried out, taking into account the immune structure of the population and the specific features of the local landscape and economy.

Age Factors↗

Hantaviruses in small wild living mammals in Czechoslovakia. Results of a 1983-1989 study.

During a 7- year period were hunted small wild living mammals and examined by ELISA and RIA techniques for the presence of hantavirus antigen and/or antibodies by MFA. In total 3,050 animals of 16 species caught in 9 out of 10 regions of Czechoslovakia, were examined. The proportion of positive animals was 4.4%. To the positive ones with the serotype 2 (Western type) belonged the following: M. arvalis, C. glareolus, P. subterraneus, A. sylvaticus, A. flavicollis. To the Eastern serotype: A. agrarius in eastern Slovakia, A. flavicollis in North of Bohemia and A. sylvaticus in South of Moravia. The repeatedly examined localities were found to be either repeatedly positive or repeatedly negative. The antigen titres in the lungs of M. arvalis were constant irrespective of sex and season of capture. They were, however, much higher in young animals, whereas the proportion of positivities was higher in adults ones. The titres of antigen in the lungs of C. glareolus never exceeded those of M. arvalis.

Animals↗

Detection of antibodies to the western and the eastern type of haemorrhagic fever with renal syndrome in patient's sera from Slovakia.

We present serological evidence of infection with western and eastern type of haemorrhagic fever with renal syndrome (HFRS) virus in patient's sera from Slovakia by indirect immunofluorescence. Treatment of sera with 2-mercaptoethanol decreased levels of haemagglutination-inhibition (HI) antibodies to the eastern type of HFRS suggesting primary infection of the patients by this virus.

Antibodies, Viral↗

[The immune structure of the population of the Bashkir ASSR in connection with hemorrhagic fever with renal syndrome and the relation of indices of collective immunity to morbidity and the nature of the landscape].

The study of 9,176 serum samples obtained from all regions and 15 cities of Bashkiria, carried out by the method of radioimmunoassay with the use of the antigen of hemorrhagic fever with the renal syndrome (HFRS), has revealed considerable differences in the size of the natural immune stratum of the population (43.9-0.8%). The size of such immune stratum characterizes the activity of natural foci: the largest immune stratum (25.4%) exists among the population of regions with broad-leaved forests, this stratum is somewhat less (12.2-13.2%) in regions with combined coniferous and broad-leaved forest, in regions with different combinations of broad-leaved forests and steppes, as well as mountain forests. On the Aĭsko-Kungurskaia forest-steppe territory and in regions characterized by a combination of steppe areas with mountain forests the immune stratum has been found to be even lesser (7.3-8.4%). The least immune stratum (3.4%) exists in steppe regions. By comparing the percentage of the population immune to HFRS and having had the diagnosis of HFRS over the period of 30 years the quality of the clinical diagnosis of this infection on the given territory may be determined.

Antibodies, Viral↗

Enzyme immuno assay for the detection of virus specific IgG and IgM antibody in patients with haemorrhagic fever with renal syndrome.

Consecutive serum samples collected from 235 patients with Haemorrhagic Fever with Renal Syndrome (HFRS), between two days and two years after onset of disease, have been analysed for the presence of IgG and IgM type of antibodies specific for Hanta-viruses. The sera were screened in parallel by a newly developed indirect Immuno Enzyme Assay (EIA) in parallel with Indirect Immunofluorescent Antibody Assay (IFA). In both tests the Hantaan virus strain 76-118 was used as the antigen. The EIA was much more sensitive than the IFA test for the detection of IgM type antibodies. With the indirect EIA IgM type antibodies against Hantaan virus 76-118 have been detected in HFRS patient's sera from the second day of illness indicating the usefulness of this test for the early serological diagnosis of this disease.

Antibodies, Viral↗

Virus-specific proteins and RNAs from cells infected with hemorrhagic fever with renal syndrome (HFRS) viruses derived from endemic areas of the U.S.S.R.

Cell-associated proteins of rodent (CG-1820 strain) and human (K-27 and 360 strains) hantaviruses isolated in the European endemic areas of the U.S.S.R. are antigenically similar as revealed by immunoprecipitation and immunoblotting assays. Nucleocapsid-associated RNAs of representative hantaviruses of four antigenic groups [Sugiyama et al. (1987) J Gen Virol 68: 979-987] have unique PAGE patterns. "Electropherotyping" of the RNAs isolated from infected cells might be used for identifying and distinguishing hantaviruses.

Animals↗

Antigenic relationship between hantaviruses analysed by immunoprecipitation.

Antigenic relationships between seven hantaviruses isolated in Sweden, Belgium, Korea, European U.S.S.R. and Asian U.S.S.R. were studied by radioimmunoprecipitation assays (RIPA) and indirect immunofluorescence tests (IFT). Animal immune sera and haemorrhagic fever with renal syndrome (HFRS) patient sera from the above countries were used. The strains fell into three antigenic groups by both RIPA and IFT: nephropathia epidemica (NE)-type, Korean haemorrhagic fever (KHF)-type and urban rat-type. This antigenic grouping conforms to the clinical grouping of the respective HFRS patients. The major cross-reactive antigen between the antigenic groups was the nucleocapsid protein. Of the two viral glycoproteins, the G2 exhibited weak cross-reactivity between the groups, while the G1 protein appeared to be the least cross-reactive. Patient sera collected at different intervals after the onset of disease showed a marked difference in their capacity to immunoprecipitate the homologous viral glycoproteins, although by IFT all sera had high titres. Host species-related antibody response differences were found by both RIPA and IFT. Using patient sera, a one-way cross-reactivity was seen between the NE-type and the KHF-type viruses. However, animal immune sera clearly demonstrated a reciprocal cross-reactivity between the two virus groups.

Antigens, Viral↗

Detection of the antigen and antibodies to the eastern subtype of haemorrhagic fever with renal syndrome virus in small rodents in Slovakia.

Direct enzyme-linked immunosorbent assay (ELISA) was used for the demonstration of haemorrhagic fever with renal syndrome (HFRS) virus antigen in lung tissue of small rodents trapped in Eastern and Western Slovakia. The eastern subtype of HFRS virus antigen was demonstrated in the lungs of Apodemus agrarius and of the western subtype in the lungs of Microtus arvalis. Antibodies to HFRS virus antigen have been detected in Apodemus species (A. agrarius and A. flavicollis) in higher titres to the Eastern subtype.

Animals↗

[Use of microcapsular leptospiral antigens for detecting specific antibodies].

The sensitivity of microcapsular leptospiral antigens, produced by Japan Lyophilization Laboratory and intended for use in tests for the detection of antibodies to leptospires in the sera of experimentally immunized laboratory animals, were studied. The comparative study of the microcapsular agglutination (MCA) test and other serological tests, such as the microagglutination (MA) test and the indirect enzyme immunoassay (EIA), was made. The leptospiral antigens under study were found to actively react with serospecific and group-specific antibodies. In infected guinea pigs and rabbits specific antibodies could be detected from days 3-4 in the MCA test and only from days 5-7 in the MA test. The average antibody level determined by titration in the MCA test was 3.3 times higher and in indirect EIA, 4.3 times higher than that determined by titration in the MA test. These data make it possible to recommend the use of microcapsular leptospiral antigens for the early diagnosis of leptospirosis.

Adsorption↗

Four serotypes of haemorrhagic fever with renal syndrome viruses identified by polyclonal and monoclonal antibodies.

Antigenic relationships among 20 strains of haemorrhagic fever with renal syndrome (HFRS) viruses isolated in Korea, China, U.S.S.R., Finland, Japan and U.S.A. were examined with rat immune sera, patient sera, eight monoclonal antibodies against the SR-11 strain and 10 monoclonal antibodies against the 76-118 strain. Antigen analyses by indirect immunofluorescent antibody and immune adherence haemagglutination tests using polyclonal and monoclonal antibodies demonstrated that HRFS viruses may be divided into four serotypes, i.e. Apodemus (Type 1), Rattus (Type 2), Clethrionomys (Type 3) and Microtus (Type 4). Further, it was demonstrated that Type 1 could be divided into three subtypes and Type 3 into two subtypes. The two sets of monoclonal antibodies were useful for identification of the antigenic types of viruses isolated from patients in endemic areas.

Animals↗

Characterization of Hantaviruses using monoclonal antibodies.

The antigenic relations among nine Hantaviruses from seven different geographic areas were examined in indirect fluorescent antibody test with 12 monoclonal antibodies. Ten monoclonals were prepared against Hantaan virus strain 76-118 and two against Hantavirus B-1, a virus isolated from a tumour in a laboratory rat. Four different serotypes have been differentiated: Hällnäs, Hantaan, Prospect Hill and Rat strain like. Two monoclonal antibodies were able to react with all nine Hantaviruses studied. Rat strain- and Hantaanvirus-specific monoclonal antibodies were documented.

Animals↗