[The characteristics of a Russian-made kit for the serological identification of streptococci groups A, B and C]. / Kharakteristika otechestvennogo nabora dlia serologicheskoi identifikatsii streptokokkov grupp A, B, C.

The first Soviet kits for the serological identification of streptococci, groups A, B, and C, on the basis of the coagglutination test were developed. Each kit was intended for 35-40 determinations. The optimum concentration of streptococci during their identification by means of the reagents making up the kit was about 1.6 x 10(9) cells/ml. The specificity of the reagents in comparison with the results of the identification of streptococci by reference methods was 97.3 +/- 0.9%. The reagents making up the kits can be presumably used for solving a number of practical problems in the epidemiological surveillance of streptococcal infection.

[The dynamics of detecting group-A streptococci in an infectious disease clinic]. / Dinamika vyiavleniia streptokokkov gruppy A v infektsionnoi klinike.

The study revealed that the isolation rate of group A streptococci in scarlet fever patients at the time of hospitalization did not exceed 68%. The isolation rate of these streptococci was greatly influenced by antibacterial therapy carried out before hospitalization. Under clinical conditions with intensive penicillin therapy group A streptococci were eliminated from the larynx on days 3-4. In 13% of children repeated streptococcal infection was observed 0.5-3 months after discharge from hospital.

[The rapid diagnosis of acute streptococcal infection in children]. / Ekspress-diagnostika ostroi streptokokkovoi infektsii u detei.

The present work deals with trials of the method of rapid diagnosis of streptococcal infection, carried out in children's infectious hospital, with the use of a new diagnostic kit. The proposed diagnosticum has proved to be highly sensitive and specific in scarlet fever and tonsillitis. The sensitivity and specificity of the diagnosticum depend on the duration of the disease, prehospital treatment and the quality of the bacteriological analysis.

[The detection of streptococci, the study of their immunobiological properties and the determination of lipoproteinase antibodies and anti-immunoglobulins in patients with acute rheumatic fever]. / Vyiavlenie streptokokkov i izuchenie ikh immunobiologicheskikh svoistv, opredelenie antitel k lipoproteinaze i antiimmunoglobulinov u bol'nykh ostroi revmaticheskoi likhoradkoi.

Bacteriological confirmation of the presence of group A Streptococcus (GAS) in patients with acute rheumatic fever (ARF) by means of the express method was achieved only in 15.1% of the cases and the positive growth of the culture was observed only in 12.1%. Streptococci isolated from the patients showed a low IgG-Fc receptor activity just as in the negative control. The blood serum of patients exhibited the presence of antibodies to 18 OF-serotypes among which serotypes 2, 4, 22, 28, 48, 68, 75, 77, 78, PT 2841 prevailed; their content fluctuated from 12.5 to 48.4%. There were no differences between the nature of distribution of the given antibodies depending on the presence and level of ASL-O in the blood and the presence of concomitant chronic tonsillitis. Antibodies to IgG in titres 1:10-1:40 were revealed in the blood of only 18.1% of the patients; there was some dependence of the frequency of their detection on the markedness of carditis and the presence of cardiac defects.

[Manifestations of Streptococcus infection resulting from various serologic groups of streptococcus]. / O nekotorykh osobennostiakh proiavlenii streptokokkovoi infektsii, vyzvannoi raznymi serogruppami streptokokka.

44 autopsy cases (from 1985 to 1990) are studied out of which in 38 cases the diseases were produced by streptococcus of group A. In 18 cases there was a pharyngeal or extra-pharyngeal generalized streptococcus infection (scarlet fever). Moderately pronounced local damage, mainly pneumonia, were found in 20 cases. In 3 other cases the disease was produced by group B streptococcus, in 2 cases by streptococcus D and in 1 case by streptococcus of G group. Group A streptococcus was encountered mainly in children older than 6 months (31 cases), B and D at an earlier age (particularly B streptococcus). Morphologically, there were no essential differences connected with different streptococcus groups. The infection in most cases was correlated with a respiratory diseases, more frequently with influenza or respiratory-syncytial infection this favouring more grave course of streptococcus infection.

[A new method for the rapid diagnosis of acute streptococcal infection]. / Novyi metod ékspress-diagnostiki ostroi streptokokkovoi infektsii.

The work deals with the development of the rapid method of the identification of acute streptococcal infection on the basis of the coagglutination test. The rapid method of the extraction of group-specific polysaccharide antigen from the cell walls of group A streptococci is proposed. The data on the use of native sera and their fractions in the development of coagglutination diagnostica have been described and analyzed. The advantages of the new method of the diagnosis of acute streptococcal infection in comparison with the traditional microbiological method are shown.

[The OF characteristics of streptococci group A and immunity to streptococcal infection based on the results of OF and anti-OF tests]. / OF-kharakteristika streptokokkov gruppy A i immunitet k streptokokkovoi infektsii po rezul'tatam OF- i anti-OF-testov.

The influence of the OF activity of group A streptococci on their specific pathogenic properties has been shown, which is manifested by increased virulence of these streptococci for children of younger age groups and by a two times higher isolation rate of OF+ strains in tonsillitis than in scarlet fever. The possibility of the indirect evaluation of the content of anti-M-antibodies by the results of the anti-OF test has been revealed, which permits using this test instead of the bactericidal test, more complicated, in the study of immunity to infection induced by group A OF+ streptococci. Among the main methods of laboratory support of epidemiological surveillance on streptococcal infection, the introduction of the highly discriminating OF typing and the anti-OF test into practical use is recommended.

[The general characteristics of the epidemic process and of the circulating streptococcal strains during an upsurge in scarlatina morbidity in Leningrad]. / Obshchaia kharakteristika épidemicheskogo protsessa i tsirkuliruiushchikh shtammov streptokokka v period pod''ema zabolevaemosti skarlatinoi v Leningrade.

The dynamics of scarlet fever morbidity in Leningrad for many years was studied and the absence of any effect produced by the existing system of preventive measures against this disease for the last 30 years was shown. On the basis of epidemiological and bacteriological data the authors came to the conclusion on the unity of the epidemic process of scarlet fever in the whole city and the relatively autonomous character of the process in individual districts. The necessity of the realization of epidemiological surveillance on streptococcal infection, with special emphasis on the multilevel social structure of the city and the wide use of the bacteriological diagnosis of streptococcal diseases, is substantiated.

[Distribution of type-specific antibodies to streptococcal lipoproteinase based on population screening data]. / Izuchenie rasprostranennosti tipospetsificheskikh antitel k streptokokkovoi lipoproteinaze po dannym populiatsionnykh obsledovanii.

In the serum samples obtained from residents of the Todzhinsky district in the Tuva Autonomous Soviet Socialist Republic antibodies to 12 out of 15 studied types of group A streptococcal lipoproteinases (OF-factor) were detected, with the prevalence of types 2, 4, 22, 25, 48, and 60, their incidence in the population constituting 34%. Antibodies to OF-antigens 58, 62, and 63 were not detected. The distribution of OF-antibodies was found to vary with sex, occurring in females 1.5 times more frequently than in males, and with age, accumulating in subjects aged 21-30 and 31-40. The distribution of antibodies to different OF serotypes did not depend on the blood serum streptolysin O titers.

[A system for insertion of heterologous DNA into chromosome of group H streptococci]. / Sistema dlia vvedeniia geterologichnykh DNK v khromosomu streptokokkov gruppy H.

A system for insertion of genes into the chromosome of group H streptococci has been elaborated. It consists of a recipient strain (Gallis GS10/1), having the fragments of lambda L-47-1 bacteriophage DNA inserted into the chromosome, and lambda 202 vector. The constructed system suggests the preliminary cloning of genes in E. coli cells with their subsequent insertion into the chromosome of group H streptococci.

Sequence relationships between plasmids associated with conventional MLS resistance and zonal lincomycin resistance in Streptococcus pyogenes.

By using electron microscopy of self-annealed DNA and restriction enzyme analysis, we have compared the physical maps of two group A streptococcal plasmids associated with conventional MLS resistance (pEL1; 20 Md) and zonal lincomycin resistance (pSM10419; 15 Md). Of their monomeric molecules, about 40% and 60%, respectively, are occupied by identical non-tandem inverted repeats containing sequences specifying putative replication functions. Sequence homology also exists between their resistance determinants which are located in unique DNA. Moreover, homology between additional regions of unknown function is so extensive and restriction fragment arrangement so similar that, formally, pSM10419 can be considered a deletion variant of pEL1. The results suggest that MLS and zonal lincomycin resistance have the same biochemical basis (i.e. methylation of 23S ribosomal RNA) and differ only quantitatively in the inducible control systems.

[Isolation and characteristics of plasmids determining multiple antibiotic resistance in strains of group A streptococci]. / Vydelenie i kharakteristika plazmidy, determiniruiushchei mnozhestvennuiu rezistentnost' k antibiotikam shtammov streptokokka gruppy A.

DNA of the streptococcal plasmid ERLI, determining resistance to erythromycin and lincomycin has been studied. The presence of satellite DNA component in streptococcal DNA has been demonstrated by dye-CsCl and CsCl density centrifugation, by chromatography of denatured-renatured DNA on the nitrocellulose and by electron microscopy. By all these methods the presence of covalently closed circular DNA molecules has been shown. Plasmid DNA has buoyant density in CsCl equal to 1.698 g/cm3 (GC content--38.8%), molecular weight (by electron microscopy) -- 19.8 Mdal; number of copies chromosomal genome equivalent is equal to about 4--4.5. Plasmid ERLI DNA was extracted from an original strain-carrier of plasmid ERLI, from a transduced strain which received plasmid ERLI as a result of transduction and lysogenization by phage "mo" and from the two antibiotic sensitive EMS mutants of resistant strain. Satellite DNA could not be isolated from a sensitive strain which served as a recipient in transduction experiments. The results obtained are in agreement with the literature on the molecular weight of the plasmid measured by the sedimentation analysis and with the previous genetic data on the antibiotic resistance within group A streptococci.

Lipoproteinase of group A streptococci and the antibodies in human sera.

The possibility of revealing lipoproteinase (serum opacity factor--OF) in hydrochloric and alkaline extracts from streptococcal cultures and the possibility of concentration and purification of this enzyme by means of gel-filtration and ion-exchange chromatography have been confirmed. When studying antibodies to OF in the blood of healthy and sick people, we were able both to reveal and to determine the titre of antibodies to OF of different serological M types (2, 4, 22/12, 22 and 49) in the sera under study (170 sera from the same number of persons). In groups of healthy people, anti-OF antibodies were shown to be present with a high frequency as well as in patients. But the titres of antibodies in the former were lower than in the latter. Most sera (32%) neutralized OF of one serological type and only 3% all types of enzymes used. The type-specificity of the anti-OF antibodies was shown. The data obtained are yet insufficient for epidemiological or clinical analysis but they point out the possibility of using the anti-OF test for these purposes.

[Antibodies to the lipoproteinase of group A hemolytic streptococci in the blood of healthy and ill persons]. / Antitela k lipoproteinaze gemoliticheskogo streptokokka gruppy A v krovi zdorovykh i bol'nykh liudei

In examining 170 samples of blood sera of healthy and sick individuals it was shown that with the aid of a simple and express antilipoproteinase test it was possible not only to reveal, but also to determine the titre of specific antibodies to the lipoproteinases of various serological M-types (2, 4, 22/12, 22 and 49) of a hemolytic streptoccus, group A. The antibodies to the enzymes were frequently revealed in the sera of adults and older children. The results obtained were still inadequate for the epidemiological or clinico-immunological analysis, but pointed to the principal possibility of using the antilipoproteinase test for the mentioned purpose.