RESUMO
The recent data on the genetic variability of the hepatitis B virus and problems of serological ELISA-mediated detection of this virus are discussed.
Assuntos
Variação Genética , Vírus da Hepatite B , Hepatite B , Ensaio de Imunoadsorção Enzimática/métodos , Hepatite B/sangue , Hepatite B/diagnóstico , Hepatite B/genética , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Humanos , Testes Sorológicos/métodosRESUMO
AIM: Study heterogeneity ofhepatitis B virus in adult patients with chronic hepatitis B and determination of diagnostic potential of modern test systems with the detection of HBsAg with amino acid substitutions in the main hydrophilic region (MHR). MATERIALS AND METHODS: In 27 hepatitis B virus samples isolated from patients with chronic hepatitis B virus infection living in Vladimir, nucleotide sequence ofgenome region corresponding to preS1/preS2/S genes was determined. RESULTS: In all of the 27 isolates genotype D virus presented by 3 subgenotypes D1, D2, D3 was detected in 18%, 26% and 56% respectively. Based on the distribution of nucleotide substitutions in the compared functional regions of hepatitis B virus (virus entry into the cell coding site (2875 - 2991 n.b.), pre-S2/S promoter region (2994 - 3171 n.b.), 5'-end pre-S2 and S-genes sequences (3172 - 154 n.b. and 155-455 n.b.), MHR (455 - 635 n.b.) and 3'-end S-gene sequence (636 - 835 n.b.), substitutions are mostly concentrated in the promoter region of the S2/S-genes (30.8%). HBsAg serotypes were determined in 24 of 27 cases by using the predicted amino acid sequence, and in 17 cases HBsAg belonged to ayw2 (71%) serotype and in 7 cases - to ayw3 serotype (29%). Amino acid substitutions G145A, M133I, S132T localized in the main hydrophilic region and P217L, S207N, V184A localized in the C-end of the protein C that are connected with diagnostic and vaccine escape were identified in 5 isolates. CONCLUSION: Diagnostic potential of test systems with the detection of HBsAg with known amino acid sequence of the MHR region were studied. Approximately equal potential of 6 test systems to detect HBsAg with amino acid substitutions G145A, M133I and S132T localized in the MHR region were shown.
Assuntos
DNA Viral/análise , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/diagnóstico , Imunoensaio , Mutação , Precursores de Proteínas/genética , Adulto , Substituição de Aminoácidos/imunologia , DNA Viral/biossíntese , Feminino , Heterogeneidade Genética , Genótipo , Anticorpos Anti-Hepatite B/análise , Anticorpos Anti-Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/classificação , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/classificação , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Fases de Leitura Aberta/imunologia , Regiões Promotoras Genéticas/imunologia , Precursores de Proteínas/classificação , Precursores de Proteínas/imunologia , Estrutura Terciária de Proteína , Federação Russa , Sensibilidade e EspecificidadeRESUMO
The diagnostic capacities of 4 commercial test systems were comparatively estimated for the detection of HBsAg, by applying a panel of samples with the established amino acid sequence of the "a" determinant of HBsAg. The Roche Elecsys HBsAg test system demonstrated the highest sensitivity - the maximum HBsAg concentrations were found in 19 of 31 cases. Escape mutations in the major hydrophilic region (MHR) of HBsAG (P120S, M133T) were responsible for differences in the sensitivity of 4 test systems by 10- to 40-fold. There were also samples that showed differences in the diagnostic capacities of the test systems to detect HBsAg, but without amino acid replacements in the area of the "a" determinant, which seems to be associated with amino acid replacements in other regions of HBsAg.
Assuntos
Antígenos de Superfície da Hepatite B/isolamento & purificação , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/diagnóstico , Kit de Reagentes para Diagnóstico , Substituição de Aminoácidos/genética , Substituição de Aminoácidos/imunologia , Genes Virais/genética , Antígenos de Superfície da Hepatite B/genética , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Humanos , Mutação , Sensibilidade e EspecificidadeRESUMO
An ultrasonic interferometer has been used to study the process of fibrin clot lysis according to the decrease in the rate of propagation of an ultrasonic wave in the latter. A significant decrease in the sound fall rate on adding epsilon-aminocaproic and trans-4-aminomethylcyclohexanecarbonic acids to the system indicates their activity inhibiting fibrinolysis. N-nicotinoyl derivatives of this compounds possess less pronounced antiplasmin activity.
