Influence of aryl hydrocarbon receptor and sulfotransferase 1A1 on bisphenol AF-induced clastogenesis in human hepatoma cells.

Bisphenol compounds (BPs) are ubiquitously existing pollutants. Recent evidence shows that they may be activated by human CYP1A1 for clastogenic effects; however, factors that influence/mediate CYP1A1-activated 4,4'-(hexafluoroisopropylidene)diphenol (BPAF) toxicity, particularly the aryl hydrocarbon receptor (AhR), sulfotransferase (SULT) 1A1 [known to conjugate 2,2-bis(4-hydroxyphenol)-propane (BPA)] and reactive oxygen species (ROS), remain unclear. In this study, a human hepatoma (HepG2) cell line was genetically engineered for the expression of human CYP1A1 and SULT1A1, producing HepG2-hCYP1A1 and HepG2-hSULT1A1, respectively.

Epidemiology and prediction of multidrug-resistant bacteria based on hospital level.

Objectives: Multidrug-resistant bacteria (MDRB) result in nosocomial infections and a substantial disease burden for hospitalised patients worldwide. However, strategies to control drug resistance at the hospital level are lacking. In this study, we aimed to find important indicators for risk assessment and predicting MDRB infections in the hospital.

Human CYP1B1-dependent genotoxicity of dioxin-like polychlorinated biphenyls in mammalian cells.

Polychlorinated biphenyls (PCBs) are persistent organic pollutants and human carcinogens. It was reported that rat CYP1A1 and catfish CYP1A can hydroxylate 3,3',4,4',5-pentachlorobiphenyl (PCB 126) and 3,3',4,4'-tetrachlorobiphenyl (PCB 77), while potential roles of other CYP1 enzymes in the metabolism of dioxin-like (DL) PCBs remain unconfirmed. In this study, three representative DL-PCBs, i.

Induction of micronuclei and cell cycle arrest by some tri- and tetrachlorobiphenyls in mammalian cells deficient in xenobiotic-metabolizing enzymes.

Polychlorinated biphenyls (PCBs) are persistent organic pollutants with continued public health concerns. The lower chlorinated biphenyls are supposed to be mutagenic following metabolic activation. However, in a preliminary study, we recently observed induction of micronuclei by several PCBs in a subclone of Chinese hamster V79 cell line, V79-Mz, which is deficient in xenobiotic-metabolizing enzyme activities.

Potent mutagenicity of some non-planar tri- and tetrachlorinated biphenyls in mammalian cells, human CYP2E1 being a major activating enzyme.

Polychlorinated biphenyls (PCBs) have been classified as human carcinogens. Mutagenicity of lower chlorinated biphenyls as well as activation of transcription factors by some other congeners may contribute to the carcinogenicity of PCBs. Recently, we reported that human CYP2E1 activates mono- and dichlorobiphenyls to mutagens.

Role of exposure/recovery schedule in micronuclei induction by several promutagens in V79-derived cells expressing human CYP2E1 and SULT1A1.

The standard procedure for the micronucleus test in cell lines requires a short exposure (≤0.5 cell cycle) to the test compounds followed by a long recovery (≥1.5 cell cycle), and in case of negative or equivocal results, a second test with extended exposure (≥2 cell cycles) without or with a recovery time.