RESUMO
A high prevalence of hepatitis B (HBV) and C virus (HCV) infections has been reported among specific patient groups in Libya; a survey was thus designed to determine the extent of the problem at the national level. A multi-stage sampling design covering all administrative areas of Libya was applied, covering > 65,000 individuals of all age groups. All subjects gave a blood sample and completed a questionnaire on demographic and risk behaviour data. The prevalence of HBV surface antigen (HBsAg) and anti-HCV were 2.2% and 1.3% respectively. The prevalence of anti-HCV increased with age, rising gradually after age 30 years, in contrast to a stable prevalence of HBsAg in all age groups 10+ years. Age-adjusted risk factors for HCV infection were previous hospitalization, surgical operations, previous blood transfusions and intravenous drug use; for HBV infection only family exposure or contact with HBV case were identified.
Assuntos
Hepatite B/epidemiologia , Hepatite C/epidemiologia , Abuso de Substâncias por Via Intravenosa/complicações , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Reação Transfusional , Adolescente , Adulto , Distribuição por Idade , Idoso , Criança , Pré-Escolar , Feminino , Hepatite B/sangue , Hepatite B/transmissão , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Hepatite C/sangue , Hepatite C/transmissão , Anticorpos Anti-Hepatite C/sangue , Anticorpos Anti-Hepatite C/imunologia , Humanos , Líbia/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Assunção de Riscos , Estudos Soroepidemiológicos , Distribuição por Sexo , Adulto JovemRESUMO
A study of 31 temperature-sensitive mutants of mouse cytomegalovirus has indicated that two mutants (tsm1, tsm31) may be defective in immediate-early/early functions, two (tsm2, tsm3) may be defective in early functions and six (tsm9, tsm18, tsm22, tsm23, tsm28, tsm30) may be defective in early/late functions while the remainder are late function-defective mutants as determined by temperature-shift experiments. Three mutants (tsm1, tsm2, tsm3) were more thermostable than wild-type virus while three (tsm16, tsm26, tsm28) were more thermolabile; the remainder were similar in their thermostability to wild-type virus.
Assuntos
Muromegalovirus/fisiologia , Mutação , Temperatura , Replicação Viral , Muromegalovirus/genética , Especificidade da EspécieRESUMO
1. The immune responses to Trypanosoma cruzi infection of germfree mice were compared to the responses of infected conventional mice. Two groups (40 animals in each group) of 2-month old female CFW germfree and conventional mice were used. The IgM and IgG which bound to the surface of T. cruzi epimastigotes determined by ELISA were significantly lower in germfree than in conventional mice (1/3 and 1/5 for IgM and IgG, respectively). 2. After infection there was a three-fold increase in the circulating levels of these immunoglobulins in germfree but not in conventional mice. Twenty-one days after T. cruzi inoculation, both IgG and IgM levels were similar in germfree and conventional animals. 3. Footpad swelling after T. cruzi-antigen inoculation was initially four-fold more intense in germfree than in conventional mice. 4. These results suggest that the reduced humoral immune response of germfree mice during the initiation of experimental Chagas' disease may be responsible for the more severe parasitism when compared to conventional mice.
Assuntos
Anticorpos Antiprotozoários/análise , Doença de Chagas/imunologia , Vida Livre de Germes/imunologia , Imunoglobulina G/análise , Imunoglobulina M/análise , Trypanosoma cruzi/imunologia , Análise de Variância , Animais , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Trypanosoma lewisi/imunologiaRESUMO
1. The immune responses to Trypanosoma cruzi infection of germfree mice were compared to the reponses of infected conventional mice. Two groups (40 animals in each group) of 2-month old female CFW germfree and vonventional mice were used. The IgM and IgG which bound to the surface of T. cruzi epimastigotes determined by ELISA were significantly lower in germfree than in conventional mice (1/3 and 1/5 for IgM and IgG, respectively). 2. After infection there was a three-fold increase in the circulating levels of these immunoglobulins in germfree but not in conventional mice. twenty-one days after T. cruzi inoculation, both IgG and IgM levels were similar in germfree and conventional animals. 3. Footpad swelling after T. cruzi-antigen inoculation was initially four-fold more intense in germfree than in conventional mice. 4. These results suggest that the reduced humoral immune response of germfree mice during ythe initiation of experimental Chagas' disease may be responsible for the more severe parasitism when compared to conventional mice