RESUMO
Particulate matter (PM) collected from mainstream tobacco smoke is a test article commonly used for in vitro genotoxicity and cytotoxicity testing of combustible tobacco products. However, little published data exists concerning the stability of PM. We completed a 2 year study to quantify the effect of PM storage at -80 °C, on the genotoxicity and cytotoxicity of PM generated from 3R4F and M4A reference cigarettes. The Ames test, Micronucleus assay (MNvit), Mouse Lymphoma assay (MLA) and the Neutral Red Uptake assay (NRU) were used. The majority of M4A and 3R4F PMs were genotoxic and cytotoxic at the timepoints tested. Some minor but statistically significant differences were observed for stored versus freshly prepared PM, but the magnitude of changes were within the variability observed for repeat testing.
Assuntos
Poluentes Atmosféricos/toxicidade , Mutagênicos/toxicidade , Material Particulado/toxicidade , Fumaça/efeitos adversos , Poluição por Fumaça de Tabaco/efeitos adversos , Poluentes Atmosféricos/classificação , Animais , Células 3T3 BALB/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , DNA/efeitos dos fármacos , Dano ao DNA , Estabilidade de Medicamentos , Concentração Inibidora 50 , Leucemia L5178/tratamento farmacológico , Leucemia L5178/genética , Camundongos , Camundongos Endogâmicos BALB C , Testes para Micronúcleos , Mutagênicos/classificação , Vermelho Neutro/metabolismo , Material Particulado/classificação , Reprodutibilidade dos Testes , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Fatores de Tempo , NicotianaRESUMO
Blood samples from female C57BL/10 mice mated with CBA/Ca males were obtained before, during and after both first and second pregnancies. A cellular enzyme-linked immunospecific assay (CELISA) was used to detect maternal antibodies against antigens on paternal splenocytes. Alloantibodies were detected in 48% of mice during or 9 days after a first pregnancy and in 82% of mice by the ninth day after the second pregnancy; these antibodies were first observed on day 10 of the first pregnancy. In two of four active multigravid sera tested, an increase in IgG1 concentration was detected; the level of all other isotypes remained within normal limits. Weak binding of alloantibody to an antigen of approximate molecular weight 44,000 was detected on CBA/Ca splenocytes by immunoblotting sera from multiparous animals. These sera also recognised an antigen of similar molecular weight on H-2b identical 129J splenocytes but not on splenocytes from the maternal strain. These results provide further information on the maternal humoral immune response during murine pregnancy.