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A P Samsonova

Publications and source records attributed to A P Samsonova.

8 recordsLinked to original sources
PubMed1997

[Development of polymerase chain reaction-based test systems for detecting leptospira in polytypical leptospirosis foci].

Two highly sensitive test systems G and B, based on the polymerase chain reaction, were developed for indication of pathogenic Leptospira interrogans, including the serovariants appearing during outbreaks in polytypical foci of leptospirosis in the tropical zone of China. These test systems can be used for rapid diagnosis of leptospirosis in humans in foci with different etiological structure.

China↗
PubMedDate not supplied

[Gene diagnostics of acute persistent Leptospira infection].

The results of clinical trials carried out in different foci have demonstrated high diagnostic value of analysis made with the use of the polymerase chain reaction (PCR) at early stages of Leptospira infection caused by infective agents of the serogroups Grippotyphosa, Canicola and Icterohaemorrhagiae. The possibility of leptospiremia lasting considerably longer than heretofore believed to be possible, as well as the persistence of leptospires in the liquor of patients after the acute phase of the disease is over, i.e. during the early and late convalescence periods, has been shown. This is indicative of good prospects of using the PCR analysis not only for early rapid diagnostics of Leptospira infections, but also for controlling the course of the infection, for prognosticating early and late complications of the disease, as well the mechanisms of pathogenesis.

Acute Disease↗
PubMedDate not supplied

[A new methodological approach for leptospira persistence studies in case of mixed leptospirosis].

A new methodical approach for Leptospira persistence studies in case of mixed leptospirosis, based on the use of PCR test systems with different taxonomic specificity for the indication and identification of leptospires, was developed. Two PCR test systems (G and B) were used in experiments on BALB/c white mice to study patterns of the development of mixed infection caused by leptospires of serovar poi (genomospecies L. borgpeterseni) and grippotyphosa (genomospecies L. kirschneri). The conclusion was made of good prospects of this method application in studies on symbiotic relationships of leptospires both in vivo and in vitro.

Animals↗
PubMedDate not supplied

[Prevalence of the gene encoding the outer membrane lipoprotein LipL32 in leptospires of different taxons].

Primers flanking the fragment sized 677 bp have been constructed on the basis of nucleotide sequences of the gene encoding the outer membrane lipoprotein LipL32. PCR-analysis was used to reveal the prevalence of gene lipL32 among 73 Leptospiraceae family strains representing different genera and genomic species. The gene lipL32 appeared to be conservative across the pathogenic species. In contrast, it was not detected in the genome of nonpathogenic free-living leptospires. Thus the developed PCR test-system with primers LEP21/LEP22 may be efficiently used to differentiate these two distinct ecological groups of leptospires.

Animals↗
PubMedDate not supplied

[Development of a test system for detecting Leptospira interrogans using the polymerase chain reaction].

Based on polymerase chain reaction a test-system has been elaborated permitting one to identify the leptospirae of the most common serogroups (Icterohaemorrhagiae, Canicola, Javanica, Ballum, Pyrogenes, Pomona, Habdomadis, Sejroe, Tarassovi) of the species Leptospira interrogans. Sensitivity of the technique is 1-10 cells in a sample. The specificity of the system has been shown to depend on the temperature of the primers annealing. The elaborated system exceeds all other systems for leptospiral identification in sensitivity. It is prospective for leptospiral identification in biological liquids aimed at early diagnosis of leptospiroses and in the studies of leptospiral persistence in host organisms in the saprophitic phase of life cycle.

DNA Primers↗
PubMedDate not supplied

[A polymerase chain reaction method for studying host persistence of pathogenic leptospira].

Polymerase chain reaction has for the first time been shown to be applicable to indication of Leptospira interrogans in the organs of infected animals with acute or chronic leptospirosis (on the model of golden syrian hamsters). Polymerase chain reaction is superior to microscopic and bacteriological analyses in identification of leptospirae in organ suspensions. The sensitivity of the technique is 1-10 cells per sample in studies of kidney or brain suspensions or 100-1000 cells in studies of liver suspensions.

Acute Disease↗