RESUMO
Shibalianwei is a large constructed wetland formed at the estuary of the Nanfei River adjoining Lake Chaohu. To investigate the distribution and pollution characteristics of nutrients and heavy metals in surface sediments of Shibalianwei Wetland, sediment samples were collected from 72 sites in July 2018. The source of the pollution was analyzed. Our results showed that the average contents of total nitrogen (TN), total phosphorus (TP), and organic matter (OM) in surface sediments of Shibalianwei were 2108.87 mg·kg-1, 1448.82 mg·kg-1, and 86.2 g·kg-1, respectively; in the external water system of the wetland, they were 2305.81 mg·kg-1, 1268.46 mg·kg-1, and 59.9 g·kg-1, respectively. The average contents of heavy metals of Mn, Cr, Cu, Pb, Cd, As, and Hg in Shibalianwei were 462.58, 42.12, 21.69, 18.05, 0.63, 5.67, and 0.059 mg·kg-1, respectively; in the external water bodies, they were 381.61, 36.85, 24.74, 30.70, 2.49, 6.47, and 0.035 mg·kg-1, respectively. In the assessments of nutrient pollution of internal water bodies of Shibalianwei, TN was at mild to moderate pollution levels, TP was at a heavy pollution level, and the comprehensive pollution index (FF) indicated that nutrients in Shibalianwei were at moderate to heavy pollution levels. The assessment results of the organic pollution index (OI) were consistent with the FF. The potential ecological risk assessments of heavy metals showed that both Cd and Hg reached certain ecological risks, which were indicated by RI and Eri. For external water bodies, the nutrient levels were also high and heavy metal pollution was relatively serious, indicating high ecological risks.
RESUMO
BACKGROUND: MicroRNAs (miRNAs) play crucial roles in tumor initiation and development. The aim of the study was to explore the clinicopathological role and functional effects of miR-504 in non small cell lung cancer (NSCLC). METHODS: Quantitative reverse transcription polymerase chain reaction (QRT-PCR) was applied to detect the expression of miR-504 in 55 cases of NSCLC tissues and matched adjacent normal tissues in NSCLC patients. MTT, colony formation and transwell invasion assays were performed to evaluate the effects of miR-504 on cell proliferation and invasion, respectively. Dual luciferase reporter assay was used to verify that LOXL2 was a direct target of miR-504. QRT-PCR and western blot analysis were performed to analyze mRNA and protein expression. RESULTS: In the study, we demonstrated that miR-504 was notably downregulated in NSCLC tissues compared with adjacent normal tissues. Lower miR-504 expression positively correlated with lymph node metastasis and advanced TNM stage in patients. Furthermore, upregulation of miR-504 significantly inhibited cell proliferation, cell invasion and EMT process of NSCLC. QRT-PCR, western blot and luciferase reporter assays confirmed that miR-504 could bind to LOXL2 3'UTR region and regulate its expression. Moreover, ectopic expression of LOXL2 could rescue the inhibiting effects on cell proliferation and invasion induced by miR-504 in NSCLC cells. CONCLUSIONS: Our results indicated that miR-504 functioned as a tumor suppressor in NSCLC and may serve as a target of NSCLC treatment.
