High urinary bisphenol A concentrations in workers and possible laboratory abnormalities.

Objectives: Bisphenol A (BPA) is widely used in epoxy resins in China. There are few reports on the adverse health effects of occupational exposure to BPA. This study examined associations between urinary BPA concentrations in workers and laboratory parameters for health status.

Terephthalic acid occupational exposure and its effect on organ functions in fiber workers.

Objectives: : To investigate the exposure to terephthalic acid (TPA), and to evaluate it's effects on organ function including the potential risk factors for uroliths and bladder tumor to TPA.

Methods: : Exposure-response modeling was carried out in a cohort of 141 TPA exposure workers and three subgroups were classified according to their urine TPA concentration. The control group consisted of 77 workers with no exposure to TPA dust.

The expression of insulin-like growth factor-I mRNA and polypeptide in rat osteoblasts with exposure to parathyroid hormone.

Objective: To investigate the insulin-like growth factor-I (IGF-I) gene and polypeptide expression in cultured rat osteoblast (ROB) and the role of IGF-I in mediating the cell-to-cell communication by mimicking the pharmacokinetics of parathyroid hormone (PTH).

Methods: The ROB was cultured with three kinds of treatment: (1) Control (Ctr), the cells were cultured without PTH during the first 6 hours and the subsequent 42 hours in a 48-hour cycle; (2) Intermittent exposure to PTH (Itm), the cells were cultured with PTH during the first 6 hours, but without PTH in the subsequent 42 hours; and (3) Continuous exposure to PTH (Ctu), the cells were cultured with PTH during the first 6 hours and the subsequent 42 hours.

Results: The bone-forming activities of ROB were increased in Itm and inhibited in Ctu.