Objective: To investigate the effects of palladium (Pd) nanoparticles on cytokine release from peripheral blood mononuclear cells (PBMCs) of control or Pd-sensitized nonatopic women. Methods: TNF-α, IL-5, IL-10 and IFN-γ release and/or expression from PBMCs incubated in presence of 5 to 10 nm Pd⁰ nanoparticles or Pd^IV salt (potassium hexachloropalladate) were determined by enzyme-linked immunosorbent assay and reverse transcription–polymerase chain reaction analysis. Transmission electronmicroscopy was performed. Results: In lipopolysaccharide-stimulated PBMCs from controls, Pd salt inhibited IFN-γ and IL-10 release, whereas Pd nanoparticles enhanced IFN-γ release and inhibited TNF-α secretion. In lipopolysaccharide-stimulated PBMCs from Pd-sensitized women showing high IFN-γ release, Pd nanoparticles inhibited TNF-α release and Pd salt IL-10 release. TNF-α and IFN-γ release and messenger RNA expression were correlated. Transmission electronmicroscopy demonstrated uptake of nanoparticles in the endocytic compartment and activation of autophagy. Conclusions: Palladium ions and nanoparticles exert different effects in vitro on the expression and release of cytokines.

Effects of Benzo[a]pyrene on Autonomic Nervous System of Coke Oven Workers: Hong‐Mei Zhang, et al. Department of Occupational Health, School of Public Health, Shanxi Medical University, China—Objectives are to investigate the effects of benzo[a]pyrene (B[a]P) on the autonomic nervous system of coke oven workers. One hundred eightyfour coke oven workers were divided into 3 groups according to their working sites (coke oven bottom group, coke oven side group and coke oven top group), and 93 referents were recruited. B[a]P monitored by air sampling pumps as well as urinary 1‐hydroxypyrene (1‐OH‐Py) was determined by high performance liquid chromatograph with a fluorescence detector (HPLCFD). The autonomic nervous system (ANS) function was determined by 4 tests: Valsalva Manoeuvre heart rate variation (HR‐V), variation of heart rate when breathing deeply (HR‐DB), variation of heart rate when instantly standing up (HR‐IS, including RR30:15 and RRmax:min) and variation of blood pressure when instantly standing up (BP‐IS). The B[a]P mean concentrations in coke oven bottom, coke oven side and coke oven top were 19, 185 and 1,623 ng/m³, respectively. The levels of urinary 1‐OH‐Py were markedly higher in the 3 exposed groups than that in the referent group (p0.05). Compared with referents, HR‐V decreased significantly in coke oven workers (p0.05). HR‐V decreased with the increment of 1‐OH‐Py (p<0.05), and results of multiple linear stepwise regression demonstrated that external exposure level and duration of education entered the HR‐V model; age was a significant factor of HR‐DB and RRmax:min, but no variable was involved in RR30:15 and BP‐IS regression. Benzo[a]pyrene affects the autonomic nervous function of coke oven workers mainly by down‐regulating the parasympathetic nervous function.