RESUMO
Marked fluctuations in sensitivity to tuberculin related to the time of nonspecific vaccinations were found in children aged 1 to 7 years vaccinated with BCG within the first week of life in annual Mantoux test (2 tuberculin units). At the age of 3 and 7 years vaccinations raise sensitivity to tuberculin causing a rise in positive reactions to tuberculin. This indicates changes in postvaccination allergy to BCG.
Assuntos
Teste Tuberculínico , Tuberculina/imunologia , Fatores Etários , Vacina BCG/imunologia , Criança , Pré-Escolar , Humanos , LactenteRESUMO
The host-controlled EcoK-restriction of unmodified phage lambda.O is alleviated in dam mutants of Escherichia coli by 100- to 300-fold. In addition, the EcoK modification activity is substantially decreased in dam- strains. We show that type I restriction (EcoB, EcoD and EcoK) is detectably alleviated in dam mutants. However, no relief of EcoRI restriction (Type II) occurs in dam- strains and only a slight effect of dam mutation on EcoP1 restriction (Type III) is observed. We interpret the alleviation of the type I restriction in dam- strains to be a consequence of induction of the function which interferes with type I restriction systems.
Assuntos
Bacteriófago lambda/genética , Desoxirribonucleases de Sítio Específico do Tipo I/genética , Escherichia coli/genética , Genes Bacterianos , Genes , Metiltransferases/genética , Mutação , DNA Metiltransferases Sítio Específica (Adenina-Específica) , Escherichia coli/enzimologia , Proteínas de Escherichia coli , GenótipoRESUMO
The EcoK restriction of unmodified phage lambda is 1000-fold alleviated in Escherichia coli grown in the presence of base analogs 2-aminopurine (2AP) and 5-bromouracil (5BU). 2AP treatment of bacteria affects specifically the type I restriction systems (EcoA, EcoB, EcoD and EcoK) and does not influence type II (EcoRI) and type III (EcoP1) restriction. 2AP-induced alleviation of restriction occurs in bacteria which are deficient in the SOS response (recA and lexA) and mismatch repair (mutH, mutL and mutS) and can be distinguished from the alleviation of restriction observed in dam- strains. We suggest that mismatches induced by 2AP and 5BU may function as an inducing signal for the alleviation of restriction observed in the presence of base analogs.
Assuntos
2-Aminopurina/farmacologia , Adenina/análogos & derivados , Bromouracila/farmacologia , Desoxirribonucleases de Sítio Específico do Tipo I/genética , Escherichia coli/genética , Bacteriófago lambda/genética , Desoxirribonucleases de Sítio Específico do Tipo I/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Genótipo , FenótipoRESUMO
2-aminopurine (2-AP) and 5-bromouracil, strong mutagens of base analog type, were found to induce efficiently the alleviation of I type restriction in Escherichia coli. 2-AP induced restriction alleviation occurs in recA, lexA and mut- mutants, but no additional relief of restriction is registered in dam-bacteria in the presence of sublethal 2-AP concentrations. 2-AP specifically alleviates I type restriction in Escherichia coli (EcoA, EcoB, EcoD, and EcoK) and does not affect restriction systems of II (EcoRI) and III (EcoP1) types. We suggest that 2-AP-induced mismatches and other replication errors may be signals inducing restriction alleviation in Escherichia coli.
Assuntos
2-Aminopurina/farmacologia , Adenina/análogos & derivados , Bromouracila/farmacologia , Reparo do DNA , Enzimas de Restrição do DNA , Desoxirribonucleases de Sítio Específico do Tipo I , Escherichia coli/genética , Escherichia coli/efeitos dos fármacos , MutaçãoRESUMO
The host-controlled EcoK-restriction of unmodified phages lambda.0 and T7ocr. is 100-fold alleviated in dam- mutants of E. coli. In addition the EcoK modification activity is considerably decreased in dam- strains. The I and III types restriction (EcoB, EcoD, EcoK and EcoP1) were relieved in dam- mutants, but no alleviation of EcoRI restriction occurred in dam- strains. We interpret the alleviation of the I type restriction in dam- mutants as consequence of induction of the function, which interferes with the I type restriction systems.
Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , Enzimas de Restrição do DNA/genética , Escherichia coli/genética , Mutação , Bacteriófago lambda/genética , Escherichia coli/enzimologiaRESUMO
Electroacupuncture diagnosis was used to demonstrate the reaction of biologically active points of the skin (BAPS) to immunization with typhus vaccine. In 7 persons immunized with chemical and live (strain E) typhus vaccines, the reaction differed significantly from the initial parameters and other measurement data obtained in a group of unvaccinated subjects. The reaction of the BAPS was noticeable starting from the first day after vaccination and was far ahead of seroimmune shifts detectable in the host. The best correlation was established between the seroimmune response and the activity of the acupuncture points on meridians X and I (a positive correlation) and on meridians III, VIII and XI (a negative correlation).