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Prenatal exposure to arsenic and mercury have been associated with adverse pregnancy outcomes that might be in part mediated by dynamic modification of imprinting gene that are emerging mechanism.The objective of this study was to examine the impacts of paternal exposure to arsenic and co-exposure to arsenic and mercury on human sperm DNA methylation status of imprinting genes, respectively.A total of 352 male subjects (23-52 years old) were recruited and demographic data were obtained through questionnaires. Urinary arsenic and mercury levels were measured using hydride generation-atomic fluorescence spectrometer. Multivariate regression model was employed to investigate the relationship between urinary arsenic levels and sperm DNA methylation status at H19, Meg3 and Peg3, measured by pyrosequencing, and evaluating the interaction with mercury.After adjusting potential confounds factors by multivariate regression model, the results indicated a significantly positive relationship between urinary arsenic levels and the methylation status of Meg3 at both mean level (β = + 0.125, p 0.001) and all individual CpGs, i.e., CpG1 (β = + 0.094, p 0.001), CpG2 (β = + 0.132, p 0.001), CpG3 (β = + 0.121, p 0.001), CpG4 (β = + 0.142, p 0.001), CpG5 (β = + 0.111, p 0.001), CpG6 (β = + 0.120, p 0.001), CpG7 (β = + 0.143, p 0.001), CpG8 (β = + 0.139, p 0.001) of Meg3 DMRs. The interaction effects analysis indicated the interaction effects of arsenic and mercury on Meg3 were not existing.Paternal nonoccupational exposure to arsenic induces the altered DNA methylation status of Meg3 in human sperm DNA. In addition, the interaction effects of arsenic and mercury on Meg3 were not existing. These findings would implicate the sensibility of sperm epigenome for environmental pollutions.

Through collecting, sorting, and analysing the research data of tungsten inert gas (TIG) welding in China and abroad, the modified TIG welding and ways to realise the improvement of the arc energy density are summarised. Based on the existing literature, two methods have been employed to improve the arc energy density. One is controlling and reducing the arc space, i.e., to compress and constrain the arc. The other is to increase the number and energy of the particles in the arc. The primary techniques to achieve the goals mentioned above are the following: adding energy to the arc, changing the arc ionisation, and increasing the arc heat dissipation. Additionally, it is indicated that further studying the mechanism of the arc energy density, especially the shape and energy distribution of the arc at the microscopic level, will provide fresh perspectives in the efficient production of TIG welding.

Polymerizable ionic liquid copolymer P(MMA-co-BVIm-Br) was synthesized by radical polymerization technique, and characterized by Fourier transform infrared spectrometry (FTIR), 1H Nuclear magnetic resonance (1H-NMR) and gel permeation chromatography (GPC). The resulting copolymer was used to prepare poly(vinylidene fluoride) (PVDF) blend membranes via a phase inversion method. The effects of the copolymer on the polymorphism, surface wettability and zeta potential (ζ) of the blend membranes were investigated by ATR-FTIR, contact angle instrument and zeta potential analyzer. Scanning electron microscopy (SEM and SEM-EDS) was also applied to investigate the morphology and the surface element changes of the fabricated membranes. The results indicated that P(MMA-co-BVIm-Br) copolymer existed on the surface of the membrane which made the blend membrane have a positive surface during the experimental pH range. The copolymer was also in favor of the formation of β crystal phase in PVDF membranes. The contact angle experiment indicated that P(MMA-co-BVIm-Br) copolymer could switch the wettability of the blend membranes from hydrophilic to hydrophobic by exchanging Br− anion with PF6−. Compared with pure PVDF membranes, the water flux and water recovery flux of the blend membranes were enhanced obviously. The results from the flux recovery ratio (FR) and total fouling ratio (Rt) all suggested that the blend membranes had good anti-fouling properties.

Wilforidine is a potentially efficient medicine to cure autoimmune diseases. In this paper, a sensitive and selective liquid chromatographic method coupled with atmospheric -pressure chemical ionization mass spectrometry (LC–APCI–MS/MS) has been developed for quantification of wilforidine in human plasma. Samples were deproteinized with acetonitrile and cleaned by solid-phase extraction. The chromatographic separation was performed on an analytical RRHD C18 column (50 × 2.1 mm) using ammonium acetate solution (10.0 mmol L−1)/acetonitrile (30/70, v/v) as the mobile phase at a flow rate of 0.7 mL min−1. Detection was carried out by the positive multiple reaction monitoring mode with transitions of m/z 780 → 684 for wilforidine, and 646 → 586 for aconitine (internal standard), respectively. The calibration curve was linear (r = 0.9991) in the concentration range of 0.5–100.0 μg L−1 with a lower limit of quantification of 0.5 μg L−1 in plasma. Intra- and inter-day relative standard deviations were less than 6.8 and 13.1 %, respectively, and the recoveries were between 88.0 and 96.0 %. This accurate and highly specific assay provides a useful method for evaluating the pharmacokinetics of wilforidine in human plasma.

Pindone is a highly effective anticoagulant rodenticide. In this paper, an improved assay for the analysis and confirmation of pindone in human plasma has been proposed. After the samples protein precipitation with 10% (v/v) methanol in acetonitrile and cleaning with solid-phase extraction, the separation was carried out on an IonPac AS11-HC analytical column (250 mm × 2 mm) using 20 mmol L−1 KOH containing 10% (v/v) methanol as organic modifier by eluent generator reagent free ion chromatography. Quantification was performed by a negative electrospray ionization ion trap mass spectrometry using diphacinone as an internal standard. The transition for quantitative analysis was m/z 229 → 172, and for qualitative analysis were m/z 229 → 145 and m/z 229 → 214 for pindone. The transition for quantitative analysis was m/z 339 → 167 for IS. The limit of detection, the limit of quantification, recovery, linearity, precision, and stability were well validated. The cracking approach of characteristic fragments for pindone and IS were proposed. It was confirmed that this method could be used in clinical diagnosis and forensic toxicology analysis.

Analysis of diphacinone is often performed on C18 column by reserved phase liquid chromatographic methods coupled with ultraviolet detection or by ion-pair chromatography coupled with mass spectrometry. In this work, a sensitive and selective method using eluent generator reagent free ion chromatography coupled with electrospray ionization ion trap mass spectrometric detection for the quantification of diphacinone in animal livers has been developed. Samples were extracted with 10% (v/v) methanol in acetonitrile after spiking with warfarin (internal standard, IS) and cleaned by solid-phase extraction. The analytes were separated on an IonPac AS11 analytical column (250 mm × 4.0 mm) using 30.0 mmol L−1 KOH (achieved by a KOH eluent generator) containing 10% (v/v) methanol as organic modifier at a flow rate of 1.0 mL min−1. Detection was performed by negative electrospray ionization and ion trap tandem mass spectrometry in multiple reaction monitoring mode with a transition of m/z 339 → 167 for diphacinone, and 307 → 161 for IS, respectively. The calibration curve was linear (r 2 = 0.993) in the concentration range of 1.0–200.0 ng mL−1 with a lower limit of quantification of 0.3 ng g−1 in animal livers. Intra- and inter-day relative standard deviations (RSDs) were less than 8.7 and 12.5%, respectively. Recoveries of diphacinone ranged from 81.2 to 89.5%. It was confirmed that this method could be used in clinical diagnosis or forensic toxicology.