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The role of BACH1 in the process of vascular smooth muscle cell (VSMC) differentiation from human embryonic stem cells (hESCs) remains unknown. Here, we find that the loss of BACH1 in hESCs attenuates the expression of VSMC marker genes, whereas overexpression of BACH1 after mesoderm induction increases the expression of VSMC markers during in vitro hESC-VSMC differentiation. Mechanistically, BACH1 binds directly to coactivator-associated arginine methyltransferase 1 (CARM1) during in vitro hESC-VSMC differentiation, and this interaction is mediated by the BACH1 bZIP domain. BACH1 recruits CARM1 to VSMC marker gene promoters and promotes VSMC marker expression by increasing H3R17me2 modification, thus facilitating in vitro VSMC differentiation from hESCs after the mesoderm induction. The increased expression of VSMC marker genes by BACH1 overexpression is partially abolished by inhibition of CARM1 or the H3R17me2 inhibitor TBBD in hESC-derived cells. These findings highlight the critical role of BACH1 in hESC differentiation into VSMCs by CARM1-mediated methylation of H3R17. [Display omitted] • Deletion of BACH1 attenuates VSMC differentiation from hESCs • BACH1 promotes VSMC marker expression by CARM1-mediated H3R17me2 • BACH1 interacts with CARM1 He et al. find that transcription factor BACH1 acts as a positive regulator for in vitro vascular smooth muscle cell (VSMC) differentiation from human embryonic stem cells (hESCs) after mesoderm induction. They show that arginine methyltransferase CARM1-mediated histone 3 arginine 17 methylation is essential for BACH1-mediated VSMC differentiation. [ABSTRACT FROM AUTHOR]

Perfluoroalkyl substances (PFAS) and organochlorine pesticides (OCPs) in surface sediments were investigated from the Bering Sea, the Chukchi Sea and adjacent Arctic Ocean in 2010. Total concentrations (dry weight) of Σ 14 PFAS in surface sediments (0.85 ± 0.22 ng g−1) of the Bering Sea were lower than that in the Chukchi Sea and adjacent Arctic Ocean (1.27 ± 0.53 ng g−1). Perfluoro-butanoic acid (PFBS) and perfluoro-octanoic acid (PFOA) were the dominant PFAS in these areas. The concentrations of Σ 15 OCPs in the sediment of the Bering Sea (13.00 ± 6.17 ng g−1) was slightly higher than that in the Chukchi and Arctic Ocean (12.05 ± 2.27 ng g−1). The most abundant OCPs were hexachlorocyclohexane isomers (HCHs) and dichlorodiphenyltrichloroethane (DDT) and its metabolites. The composition patterns of HCHs and DDTs indicated that they were mainly derived from the early residues via river runoff. Increasing trends of PFAS, HCHs and DDTs in surface sediments from the Bering Sea to the Arctic Ocean were found, indicating oceanic transport. In summary, the concentrations of OCPs were orders of magnitude greater than the observed PFAS concentrations, and the concentrations of PFAS and OCPs in surface sediments from the Bering Sea to the Chukchi Sea and adjacent Arctic Ocean are at the low to moderate levels by comparing with other coastal and marine sediments worldwide. • PFAS and OCPs were determined in surface sediments of the adjacent Arctic Ocean. • OCPs were orders of magnitude greater than the observed PFAS. • PFOA was the main compound, and the most abundant OCPs were HCHs and DDTs. • Industrial activities may be responsible for high levels of PFAS in the Bering Sea. • An increasing latitudinal trend of OCPs were observed. [ABSTRACT FROM AUTHOR]

Riverine runoff is one of the most important pathways of pollutants entering the oceans. To study the seasonal variations, spatial transports, sources and mass fluxes of polycyclic aromatic hydrocarbons (PAHs) from the subtropical Jiulong River watershed to estuary, water samples were collected in wet and dry seasons. PAH concentrations showed significant temporal-spatial variations (ANOVA, p < 0.05). In the watershed, PAH concentrations in wet season (48.6 ± 18.2 ng L−1) were significantly lower than in dry season (90.3 ± 18.5 ng L−1). In contrast, estuarine PAH concentrations in wet season (67.1 ± 24.6 ng L−1) were significantly higher than in dry season (27.4 ± 10.6 ng L−1) (p < 0.0001). The spatial variations of PAH concentrations in wet and dry seasons reflected positive and restricted transport processes occurred in the river. These findings might be subjected to seasonal changes in precipitation, water discharge, hydrodynamic conditions, and human activities. The compositional patterns of PAHs illustrated that fluorene and phenanthrene were the dominant compounds in the watershed, while phenanthrene was predominant in the estuary. Source analysis by molecular diagnostic ratios and PMF model indicated that fossil fuel and biomass combustion and petroleum both contributed to the presence of PAHs, and the high contributions of pyrogenic PAHs might be related to urban rainstorm runoff in winter and atmospheric inputs in winter. Although the estimated flux of PAHs from watershed to estuary was about 676 kg yr−1 with a low level by comparing the data obtained in the worldwide, continue concern of PAHs in the Jiulong River is recommended due to the intense human activities. • PAH concentrations displayed significant temporal and spatial variations. • Compositional patterns of PAHs were different between watershed and estuary. • Combustion and petroleum both contributed to the presence of PAHs. • Fluvial transport of riverine PAHs was dominate in summer than in winter. • Flux of riverine PAHs transported to the estuary was at a low level globally. [ABSTRACT FROM AUTHOR]

On July 27, 2003, a spill of approximately 31,000 tons of Iranian light crude oil affected the coast of Karachi, Pakistan. Approximately 11 years after the spill, we analyzed polycyclic aromatic hydrocarbons (PAHs) and their alkylated homologues (alkyl-PAHs) as the indicators to evaluate the residual effect of oil spill to the sediment along the Karachi coast. The total concentrations (dry weight) of parent PAHs and alkyl-PAHs ranged from 121.9 to 735.4 and 42.3–1149.9 ng/g, respectively. The estuary and harbor were the two regions with the highest levels of PAHs in the sediment. Conversely, sedimentary PAHs in the oil spill areas and remote coastal areas showed significantly lower levels. Although the results of the source identification indicated the up to 75.2% of the contribution from petroleum and its derivatives, this could only reflect the direct impact of the Karachi city on the presence of PAHs in the coastal sedimentary environment and did not indicated that the oil spill continues to stay 11 years later. Compared with 11 years ago, the sharply reduced PAH content, great changed composition, and the degradation driven trend of diagnostic ratios all indicated a sharp decrease in the influence of PAHs caused by the oil spill. Finally, the ecological risk caused by the PAH residual in the marine sedimentary ecosystem had disappeared along the Karachi coasts, Pakistan. • The concentrations of ∑ 16 PAHs in sediment was decreased 11 years after oil spill. • ΣP-PAHs and ∑alkyl-PAHs provided better information to evaluate oil spill. • PCA-MLR was employed to identify the petroleum-related sources of PAHs in sediment. • PAHs would be unlikely to cause adverse effects. [ABSTRACT FROM AUTHOR]

Abstract Semi-permeable membrane devices (SPMDs) were applied to sample some Organochlorinated Pesticides (OCPs), Polycyclic Aromatic Hydrocarbons (PAHs) and Polychlorinated Biphenyls (PCBs) from the seawater of 14 Chinese coastal areas. The total concentrations of OCPs (∑ 16 OCPs), PAHs (∑ 15 PAHs) and PCBs (∑ 35 PCBs) were in the ranges of 489.2–2174, 589.4–53,160, and 133.2–3658 ng/g lipid, respectively. The ∑ 15 PAHs varied significantly with the sampling locations, which were far higher in north Chinese coastal areas than in south areas, whereas ∑ 16 OCPs and ∑ 35 PCBs only slightly fluctuated along the entire coast line. Comparing SPMD to grab sampler, it was found that the distribution patterns of the PCBs and OCPs in seawater were generally similar. However, the compositional profiles of the PAHs, PCBs, DDTs and HCHs in SPMDs were slightly different to grab samplers and organisms. The SPMDs accumulated less lipotropic compounds, which are inclined to dissolve in water rather than in organisms. Graphical abstract In the present study, the concentrations of PAHs, PCBs and OCPs in the seawater of Chinese coastal areas using SPMDs were reported. This figure illustrated that OCPs and PCBs did not vary significantly along the whole coast line, while PAHs residual levels in the Yellow Sea and East China Sea were relatively higher than other coastal areas in Chinese coasts. Unlabelled Image Highlights • The PAHs, PCBs and OCPs in entire Chinese coastline seawater using SPMD were reported. • The concentrations of PAHs in north sea area were much higher than in south. • The spatial distribution presented by SPMD was basically consistent to grab sampler. • The OCs compositions and source diagnosis ratios in SPMDs were different to organisms. [ABSTRACT FROM AUTHOR]

The seasonal variations and spatial distributions of fifteen perfluoroalkyl substances (PFASs) were investigated in the water of the subtropical Jiulong River Estuary (JRE) in Fujian, China. The concentrations and composition profiles of PFASs showed significant seasonal variations. ∑PFASs concentrations ranged from 4.8 to 37.6 ng L −1 , 12.2 to 110 ng L −1 and 3.3 to 43.0 ng L −1 in the dry, medium and wet seasons, respectively. Perfluorooctane sulfonate (PFOS) was found to be the most abundant PFAS in the dry season, with a composition of 33% ± 5%, Perfluorohexanoic acid PFHxA (47% ± 13%) and perfluoropentanoic acid (PFPeA) (52% ± 15%) were the dominant compounds in the medium and wet seasons, respectively. Seasonal and spatial distributions of ∑PFASs were different in the upstream and downstream sections. High concentration of PFHxA occurred in the medium season, and showed a linear decreasing trend from upstream to downstream. The majority of other PFASs did not show clear seasonal variation. Composition profiles indicated that the JRE was mainly contaminated by short-chain perfluoroalkyl carboxylic acids (PFCAs), shipbuilding industry, multiple wastewater and river runoff were identified as major potential sources. [ABSTRACT FROM AUTHOR]