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L N Chernousova

Publications and source records attributed to L N Chernousova.

At least 37 records · Page 2Linked to original sources
PubMed2000

[The comparative cultural-biochemical and immunochemical identification of laboratory strains of cultured mycobacteria from leprous patient lesions and from soil].

The paper presents the results of studied of cultural biochemical and immunochemical properties of the cultured mycobacteria isolated from patients with leprous lesions of (M.01, M.011) and the soil (M. lufu) in compared to other well-known mycobacteria and between them. M.01, M.011, and M. lufu differ from other representatives of the genus Mycobacterium, but they are close to each other in their cultural biochemical and immunochemical properties, antigenic composition, and protein spectra. The findings are an additional characteristic of the biological properties of M.01, M.011, and M. lufu.

Animals↗
PubMed1999

[Detection and characteristics of rpoB gene mutations in rifampicin-resistant clinical strains of M. tuberculosis].

The resistance of M. tuberculosis to rifampicin, one of the key agents used in the treatment of tuberculosis is due to point mutations in the rpoB gene encoding for the B-subunit of PNA polymerase. Based on the detection of such mutations, genotypic determinations of rifampicin resistance is a serous alternative to routine microbiological assays that take much more time. Nevertheless, the efficiency of genotypic methods largely depends how completely the resistance-associated mutations are studied and characterized. It is shown that the types and detection rates of certain rpoB mutations can greatly vary in the Mycobacterium strains spread in different geographical regions. By applying the approach based on the direct sequencing of PCR with rpoB gene fragments, the present paper analyzed 48 rifampicin-sensitive and 52 rifampicin-resistant clinical M. tuberculosis strains provided by Moscow tuberculous control facilities. Mutations responsible for rifampicin resistance were detected in 51 (98%) of the 52 resistant strains. The mutations involving codons 531 (46%), 526 (23%), and 516 (23%) of the rpoB gene were proved to be dominant. An unusual double mutation combining the replacement of F by L in codon 514 and previously uncharacterized methionine deletion in the position 515 was detected in the single investigated strain. The efficiency of the employed approach for rapid diagnosis of rifampicin-resistant M. tuberculosis strains is discussed.

Antibiotics, Antitubercular↗
PubMed1997

[Interaction of Mycobacteria isolated from sarcoidosis patients with antituberculosis antibodies].

In 80% of cases, antituberculosis antibodies from the sera of patients with tuberculosis were ascertained to react in enzyme immunoassay (EIA) with antigens (ultrasound disintegrants (USDs)) of reverse mycobacteria isolated (initially) from patients with sarcoidosis. The USDs of reverse mycobacteria isolated from patients with sarcoidosis reacted in EIA with monoclonal antibodies (MAb) against M. tuberculosis complex antigens (unique and crossover). Both common and distinctive (unique) antigenic determinants were detected via MAb against different mycobacterial types by immunoblotting in the antigenic complexes of M. tuberculosis H37Rv and reverse strains isolated from patients with sarcoidosis.

Animals↗
PubMed1997

[Examining of humoral immunity on mycobacteria antigens in sarcoidosis].

Antibodies to Mycobacterium tuberculosis antigens H37Rv and reverse strains previously isolated from patients with sarcoidosis with granular isolates were determined in 50 patients with sarcoidosis (including 16 patients isolating granular types) and 56 patients with tuberculosis, by using ELISA and immunoblotting. Serum antibodies from patients with sarcoidosis were ascertained to more commonly react in ELISA with the antigen (ultrasound disintegrant (USDs) obtained from reverse mycobacteria isolated (initially) from patients with sarcoidosis (AGS) than with the USD of the M. tuberculosis H37Rv (AGT) and, on the contrary, serum antibodies from patients with tuberculosis more frequently reacted with the M. tuberculosis H37Rv. The spectrum of serum antibodies from patients with sarcoidosis greatly differed at immunoblotting with AGS and AGT. There was most commonly a reaction with the antigenic determinants 79, 27, 30, and 50 kDa to AGS and that of the determinants 17, 35, 32 kDa to AGT.

Adult↗
PubMed1996

Serodiagnosis of tuberculosis: detection of mycobacterial antibodies and antigens.

SETTING: The diagnosis of tuberculosis is based primarily on identification of mycobacteria and on clinical evidence. Recently, serological studies have been widely used experimentally as a diagnostic approach. OBJECTIVE: The aim of our study was to optimize serodiagnosis of tuberculosis by detecting mycobacterial antigens and antibodies in sera from patients with lung tuberculosis, non-related diseases and healthy controls. DESIGN: Mycobacterium tuberculosis H37Rv was disintegrated by pressure. Cell walls were extracted with 3 M KCL and were subjected to gel filtration in Toyopearl gel. Immune sera were prepared by immunization of rabbits with cell wall material. Anti H37Rv antibodies were purified by affinity chromatography. The reagents obtained were used to detect serum antibodies and antigens (following immune complex dissociation) using ELISA. RESULTS: Using fraction 6 of cell wall extract, antibodies were detected in 72.2% of TB patients; there were no positive reactions in control subjects. By use of affinity-purified antibodies, antigens were detected in 77.1% of TB patients, 10% of patients with unrelated diseases and 6.7% of healthy controls. CONCLUSION: Effective serodiagnosis of tuberculosis can be achieved only by combining detection of both circulating antibodies and antigens using highly specific purified reagents and immune complex-dissociated sera.

Antibodies, Bacterial↗
PubMed1996

Association of various genetic markers with tuberculosis and other lung diseases in Tuvinian children.

SETTING: Heredity factors influence susceptibility to tuberculosis and other lung diseases. Recent immunogenetic studies have confirmed the genetic predisposition to lung diseases in different populations. Precise knowledge of genetic aspects of disease susceptibility is important for improvement of public health. OBJECTIVE: The aim of our research was to study the distribution of certain genetic markers in Tuvinian children suffering from tuberculosis and other lung diseases and to compare it with that in ethnically- and age-matched healthy donors. HLA-A, -B, -C and -DR antigens have been defined serologically by lymphocytotoxic assay, and variants of polymorphic protein loci Hp, Tf, Gc, ESD, ACP, PGM1, ADA, PGD have been defined by electrophoresis. RESULTS: It was demonstrated that in Tuvinian children with tuberculosis the frequencies of HLA-DR2 and HLA-DRw53 antigens are increased in comparison with healthy donors. In children with non-tuberculous chronic lung diseases with allergic components the frequency of HLA-A1, -B5 and -B8 antigens and of genetic variants Hp2-2 and ESD1-1 was elevated. CONCLUSION: HLA complex genetic factors influence susceptibility to tuberculosis and other lung diseases in Tuvinian children.

Adolescent↗
PubMed1996

[S and R forms of Mycobacterium tuberculosis as a problem of producing cloned and phenotypically competent strains].

The authors suggest that animals and humans carry M. tuberculosis in S form. These mycobacteria are virulent, do not form conglomerates and represent biologically most potent form. The state of R-form M. tuberculosis results from their culturing on artificial culture media which fail to secure compatible conditions for cells. M. tuberculosis S-form is convenient for microbiological and molecular-genetic research. The authors offer a method of biological production of single M. tuberculosis in S form.

Culture Media↗
PubMed1996

[The isolation and characteristics of monoclonal antibodies to Mycobacterium smegmatis and M. kansasii].

Immunization of BALB/c mice with sonicates of M. smegmatis and kansasii and fusion of splenocytes of the immunized mice with cells of syngeneic myeloma P3X63Ag8653 yielded hybrid clones synthetizing antibodies to these antigens. The selection of hybrid clones and analysis of the antibodies specificity were performed at ELISA using the immunization antigens and antigens from other mycobacteria and E. coli. To define immunoglobulin class of the antibodies the authors used antiglobulin sera of class A, M, G. The monoclonal antibodies belonged to IgG. Molecular mass of polypeptides carrying the epitope against which the antibodies were directed was measured at immunoblotting. Two antibodies reacted only with M. smegmatis, 38 and 10 kD proteins. The other 2 cross-reacted with other mycobacteria and were directed against epitopes on polypeptides varying in molecular mass.

Animals↗
PubMed1996

[New microbiological Techniques in diagnosis of tuberculosis].

Microbial spectrum in patients with disorders of the upper respiratory tract consisted mainly of streptococci, staphylococci and pneumococci in 1991-1993, 1994 and later, respectively. Most specific for detection of nontuberculous flora was brushing with protecting agar plugs in combination with transport medium and anaerobic culturing. Direct immunofluorescence allows detection of antigens M. chlamydia in 29.4%, M. pneumoniae in 18.5% of cases. In diagnosis of tuberculosis the following new technologies were introduced: bacterioscopy with previous culturing of the material on liquid culture media followed by biological test and polymerase-chain reaction; determination of drug resistance based on nitrate reductase activity of M. tuberculosis indicating resistance of M. tuberculosis on liquid media in 4-7 days, dense egg media in 8-12 days, usage of Popesku medium enables correction of tuberculosis chemotherapy one month after the test initiation; M. tuberculosis identification using Western blot with monoclonal antibodies in some cases for 7 days.

Diagnosis, Differential↗
PubMed1996

[Advances in microbiological diagnosis of tuberculosis and sarcoidosis].

Combined microbiological investigation of diagnostic material containing granular mycobacteria has revealed cultures-revertants both in tuberculous and sarcoidosis patients. Identification of the isolated cultures provided the conclusion on identity of granular mycobacterial structures discovered both in tuberculous and sarcoidosis patients.

Animals↗
PubMed1995

[Principles and methods of immunodiagnosis in tuberculosis].

The paper provides data on the current principles of tuberculosis immunodiagnosis, characterizes agents (antibodies, antigens, recombinant proteins, anti-idiotypes) used for these purposes, describes some difficulties arising in designing antigen and antibody diagnostic kits, presents the results of using various agents for the immunodiagnosis (primarily for serodiagnosis) of tuberculosis, discusses the diagnostic problems of tuberculosis during mass surveys and at tuberculosis hospitals. The results obtained at the Central Research Institute of Tuberculosis are given on the above issues along with references.

Diagnosis, Differential↗
PubMed1995

[Detection of Mycobacterial antigens in tuberculous pleuritis, empyema and meningitis].

Mycobacterial antigens were identified by inhibition solid-phase enzyme immunoassay specific antibodies to M.H37Rv labelled with horse radish peroxidase in 20, 27, 24, 47 and 21 patients with tuberculous pleurisy, tuberculous empyema, meningitis, pleurisy and nontuberculous empyema, respectively. Mycobacterial antigens were found more frequently and in greater quantities in pleural and cerebrospinal fluids in tuberculosis than in the above nontuberculous affections. These differences were less pronounced in serum assays.

Antigens, Bacterial↗
PubMed1995

[Biological characteristics of M. tuberculosis and difficulties in microbiological diagnosis of tuberculosis].

The paper outlines difficulties in tuberculosis diagnosis and effectiveness of various methods of mycobacteria identification. The latter along with direct and indirect determination of mycobacterial drug resistance require perfection. There is a need in investigation of diagnostic samples from tuberculous and respiratory sarcoidosis patients for mycobacterial granular forms. A multimodality diagnostic approach to examination of clinical material from tuberculous patients is advocated.

Adult↗
PubMed1995

[Affinity isolation of mycobacterial antigens on monoclonal antibodies].

Affinity chromatography on monoclonal antibodies specific to tuberculous mycobacteria was used to isolate mycobacterial antigens from ultrasonic disintegrate M. tuberculosis H37Rv. Disk-electrophoresis on polyacrylamide gel showed purified antigens to consist of polypeptides with molecular mass 16, 19, 32, 60, 27, 70 and 55 kD. The antigens were tested for enzyme immunoassay of antibodies in the sera from patients with infiltrative pulmonary tuberculosis.

Adolescent↗