Occurrence, spatial distribution, and risk assessment of short- and medium-chain chlorinated paraffins in sediment from black-odorous rivers across China.

Chlorinated paraffins (CPs) were massively produced for varied industrial purposes, of which improper handling and consequent environmental release resulted in worldwide contamination. The present study investigated the occurrence and spatial distribution of short- and medium-chain chlorinated paraffins (SCCP/MCCPs) in 171 sediment samples from black-odorous urban rivers across China. Total SCCP and MCCP concentrations ranged from 8.3 to 9.4 × 104 (median: 1.1 × 103) ng/g dw, and from not-detected-value to 1.0 × 106 (median: 1.3 × 104) ng/g dw, respectively. No clear spatial distribution of SCCPs and MCCPs was observed since black-odorous urban rivers were polluted by point-sources of the SCCP/MCCPs. Significant positive correlations were identified between SCCP/MCCPs and total organic carbon, and between SCCP/MCCPs and other persistent organic matter, including polybrominated diethyl ethers, polychlorinated biphenyls, antibiotics, and plasticizers. The average ratios of MCCPs to SCCPs in most samples were divided into 11 and 16, implying the manufacturing and use of at least two types of CP technical mixtures in China. The composition of SCCP/MCCPs were similar to that in their commercial products. Ecological risk assessments by two approaches, including the Federal Environmental Quality Guidelines and Risk Quotient, both revealed that SCCP/MCCP in surface sediments confer an ecological risk. ENVIRONMENTAL IMPLICATION: SCCPs and MCCPs can be considered "hazardous materials" because of their massive production and their potential persistence, long-distance transfer, bioaccumulation potential, and toxicity. This research conducted a comprehensive study on SCCP/MCCP in black-odorous urban river sediments across China and revealed their environmental risk, which may improve understanding of SCCP/MCCP contamination characteristics.

[miR-520a-3p regulates the signaling pathway of cytokine secretion in cervical cancer].

OBJECTIVE: To investigate the molecular mechanism of miR-520a-3p regulating the secretion of cytokines in cervical cancer. METHODS: The matching between miR-520a-3p and the NF-κB complex subunit RELA was analyzed by TargetScanHuman, and then the luciferase reporting system was used to detect whether miR-520a-3p targeted the NF-κB complex subunit RELA. After cervical cancer HELA cells stimulated by LPS, in the overexpression group or the knockout group, miR-520a-3p mimics or inhibitor were mixed with transfection reagent and dripped into HELA cells. The expression levels of colony stimulating factor (GCSF), granulocyte-macrophage colony stimulating factor (GM-CSF), interleukin 2 (IL-2), interleukin 3 (IL-3), interleukin 4 (IL-4), interleukin 5 (IL-5), interleukin 6 (IL-6), interleukin 19 (IL-9), interleukin 10 (IL-10), interleukin 12 p40 (IL-12 p40), interleukin 12 p70 (IL-12 p70), interleukin 13 (IL-13), interleukin 17 (IL-17), interferon gamma (IFN-γ), monocyte chemoattractant protein-1 (MCP-1), monocyte chemoattractant protein-5 (MCP-5), small inducible cytokine A5 (RANTES), tumor necrosis factor-alpha (TNFα) were detected by enzyme-linked immunosorbent assay in both the overexpression group and the knockout group. Each experiment was repeated three times. RESULTS: miR-520a-3p targeted the 3'UTR of RELA. After activation of the NF-κB signaling pathway by lipopolysaccharide (LPS), the protein expression levels of cytokines GCSF, GM-CSF, IL-2, IL-3, IL-4, IL-5, IL-6, IL-9, IL-10, IL-12 p40, IL-12 p70, IL-13, IL-17, IFN-γ, MCP-1, MCP-5, RANTES, TNFα secreted by HELA cells of cervical cancer were increased significantly (P＜0.05). In the overexpression group, the protein expression level of RELA of NF-κB complex subunit was decreased, and the protein expression level of the above-mentioned cytokines secreted by HELA cells of cervical cancer were decreased (P＜0.05). In the knockdown group, the protein expression level of RELA, a subunit of NF-κB complex, and the protein expression level of the above-mentioned cytokines secreted by HELA cells of cervical cancer were increased (P＜0.05). CONCLUSION: miR-520a-3p inhibits cytokine secretion in HELA cells of cervical cancer by targeting RELA, a key molecule in the NF-κB signaling pathway.

[Studies on chemical constituents of green algae Ulva pertusa].

OBJECTIVE: To study the compounds from Ulva pertusa. METHOD: The alga was extracted with ethanol, isolated and purified by column chromatography on silica gel and sephadex LH -20. All the compounds were identified on the basis of spectral analysis (including IR, MS, NMR). RESULT: Seven compounds were elucidated as cis-asarone (1), trans-asarone (2), gamma-asarone (3), trans-phytol (4), phytyl-stearate (5), phytyl-acetate (6), isophytol (7). CONCLUSION: All other compounds were isolated for the first time from U. pertusa, except for the compound 4.