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V S Kiktenko

Publications and source records attributed to V S Kiktenko.

At least 19 recordsLinked to original sources

[A comparative evaluation of the sensitivity of different methods for the serological diagnosis of leptospirosis].

In this work the comparative evaluation of the sensitivity and serological specificity of the microcapsular agglutination (MCA) test, the passive hemagglutination (PHA) test and the microagglutination (MA) test are presented. In the MCA test leptospiral antigens, adsorbed on synthetic carrier capsules produced by Japan Lyophilization Laboratory, were used and the PHA test was made with the use of polyvalent erythrocyte diagnosticum. The study of blood serum samples from 46 leptospirosis patients revealed that the values of antibody titers in the PHA and MCA tests were 5.5-8.1 times higher than the traditional MA test. In the MCA and PHA tests antileptospiral antibodies could be detected as early as on days 1-3 of the disease when the results of the MA test were negative or very low. The maximum values of antibody titers in the MCA and PHA tests were detected on days 11-15 of the disease and in the MA test, on days 21-25. The MCA and PHA tests are genus-specific and permit the detection of antileptospiral antibodies irrespective of the serogroup of the infective agent. In the study of the blood sera of 40 patients with diseases of nonleptospiral etiology the MCA and MA tests yielded false positive results in 7.5% and the PHA test, in 12.5% of cases in titers below the diagnostic level. These data are indicative of high sensitivity and specificity of the serological tests used in this study.

Agglutination Tests↗

[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↗

Investigation of hemolytic activity of leptospirae on solid culture media.

Results of investigation of hemolytic activity of leptospirae against red blood cells of various animal species on solid culture media using the technique of agar layers are presented. It has been shown that hemolytic properties of pathogenic and saprophytic leptospirae differ with respect to red blood cells of the sheep, the rabbit, the hamster, the albino rat and the albino mouse. Hemolytic activity of leptospirae regarding the erythrocytes of the cattle, the horse and the fowl depends on the strain of leptospirae. The advantage of using solid nutrient media for the determination of hemolytic properties of leptospirae in comparison with liquid media has been demonstrated.

Animals↗

[The use of direct immunoenzyme analysis with genus-specific peroxidase conjugate in leptospirosis].

For the first time anti-Patoc I peroxidase conjugate was obtained from the serum of a hyperimmunized guinea pig by the method of Nakane and Kawaoi (1974) in the modification of Mathiesen et al. (1978). In the experimental study of 37 Leptospira strains belonging to 19 serological groups, carried out with the use of direct EIA techniques, anti-Patoc I peroxidase conjugate was found to be genus-specific and highly active. The possibility of detecting Leptospira antigens of 7 serological groups in the blood and in suspensions of the liver and kidneys of golden hamsters by direct EIA with the use of the above-mentioned conjugate was established. The use of direct EIA with anti-Patoc I peroxidase conjugate for the diagnosis of leptospirosis is recommended.

Animals↗

Influence of the mechanism of transmission of the infective agent on the aetiological structure of leptospiral foci.

It has been demonstrated that the differences observed in the aetiological structure of the individual foci of leptospirosis can be explained not only by the affinity of leptospiral serogroups to certain animal species, but also by different mechanisms of transmission of the causative agent of leptospiral infection which can be transferred both by sexual and alimentary routes (in water). It has been demonstrated that mostly one serotype of leptospires predominates in natural foci of leptospirosis, but several in anthropurgic ones. In the author's opinion, leptospiral infection in natural foci is mainly spread by the sexual route through the background species of animals--carriers of leptospirosis, and by the alimentary route in the anthropurgic foci. It is presumed that leptospires of the serogroups Javanica, Australis, Icterohaemorrhagiae, transmitted by the shrew-mice, hedgehogs and rats by the sexual route, are by their origin "ancient" serogroups of leptospires while the serogroups of leptospires isolated from domestic animals, showing predominantly the alimentary route of transmission of infection in the focus, are representatives of the "younger" forms of the evolutional development of leptospires.

Animals↗

[Dynamics of Leptospira colony formation on solid nutrient media].

The formation of Leptospira colonies on solid culture media varying in composition were studied. In all species of Leptospira 3 main periods of colony development were revealed, each of them having its characteristic morphological changes connected with the growth of the colony deeply into agar.

Culture Media↗

[Significance of an increase in the titer of agglutinins in the microagglutination test in leptospirosis].

The authors considered different views of investigators on the diagnostic antibody titre level in the microagglutination test (MAT) in leptospirosis of man and animals. Some of them took into consideration MAT in low titres (1:10-1:20), and others - in high only (1:400, 1:1000), which gave no possibility to assess the state of leptospirosis morbidity. The authors suggest that the assessment of the level of the titres in single and repeated studies should be approached differentially. In single examination 1:100 and over should be considered as a positive MAT titre for man, 1:200 and over - for cattle, 1:20 and over - for swine, and 1:20 and over for murine rodents. In repeated investigations any level of the titre in case of its dynamics should be taken into consideration.

Agglutination Tests↗

[Antigenic structure of saprophytic leptospirae and their classification].

The authors present the results of study of the serological properties of 46 strains of saprophytic leptospirae of different origin. On the basis of the affinity of the antigenic structure detected in the cross microagglutination reaction (MAR) 38 strains under study were united into 8 serological groups; the rest 8 strains were serologically independent in this reaction. The fact that 9 strains of water leptospirae isolated in the Armenian SSR belonged to one serological group was proved in the cross MAR and the test of aglutinin adsorption. This serological group was new and was named L. armenica. Five individual serological types of saprophytic leptospirae were differentiated in its composition. Comparative study of the serological interrelations between the group of strains isolated in Armenia and the strains of some serological groups and serological types the closest serological connections were noted in the K-1030 (serological group Armenica) and Bovedo (serological group Andamana) strains. It is believed that the existing division of the saprophytic leptospirae into two serological groups (Semaranga and Andamana) required widening and supplement by new serological groups and serological types.

Agglutination Tests↗

Leptospirosis infection through insemination of animals.

The semen of animals in spontaneous and experimental leptospirosis was investigated by bacteriological, immunological and biological methods. It has been found that pathogenic leptospirae (L. pomona, L. hebdomadis) are well preserved in the semen and in media used for its dilution. Leptospirae are eliminated with the semen. The initial strain of the agent was isolated from the semen and secretions of 6 out of 26 experimentally infected rabbits and 4 spontaneously recovered bulls (L. hebdomadis). Specific leptospiral antibodies appear in the semen of infected animals. The dynamics of the titre of these antibodies corresponds to the dynamics of the antibody titre in the blood. It is recommended to use the sement for the agglutination reaction. The application of semen infected with pathogenic leptospirae for artificial insemination causes the animals falling ill with leptospirosis accompanied by abortions, reduced fertility and stillbirths of rabbits.

Animals↗

Leptospirosis infection through insemination of animals.

The semen of animals in spontaneous and experimental leptospirosis was investigated by bacteriological, immunological and biological methods. It has been found that pathogenic leptospirae (L. pomona, L. hebdomadis) are well preserved in the semen and in media used for its dilution. Leptospirae are eliminated with the semen. The initial strain of the agent was isolated from the semen and secretions of 6 out of 26 experimentally infected rabbits and 4 spontaneously recovered bulls (L. hebdomadis). Specific leptospiral antibodies appear in the semen of infected animals. The dynamics of the titre of these antibodies corresponds to the dynamics of the antibody titre in the blood. It is recommended to use the semen for the agglutination reaction. The application of semen infected with pathogenic leptospirae for artificial insemination causes the animals falling ill with leptospirosis accompanied by abortions, reduced fertility and stillbirths of rabbits.

Animals↗

Nucleic acid content and nucleotide composition of DNA in leptospirae.

The contents of DNA and RNA were studied in 9 strains of leptospirae and the composition of nitrogen bases of DNA in 20 strains of pathogenic and saprophytic leptospirae. It has been found that leptospirae contain a high per cent ration of nucleic acids. According to the nucleotide composition, the family of Leptospira as a whole belongs to the AT-type. According to overall guanine and cytosine contents, the investigated strains of pathogenic leptospirae fall into 3 groups and differ from the seprophytic strains. With respect to the limited number of the investigated strains, the DNA nucleotide composition of leptospirae can be used as a supplementary biochemical criterion in the classification of leptospirae.

Chromatography, Paper↗