MiR-26a functions as a tumor suppressor in ambient particulate matter-bound metal-triggered lung cancer cell metastasis by targeting LIN28B-IL6-STAT3 axis.

Exposure to ambient particulate matter (PM) has been linked to the increasing incidence and mortality of lung cancer, but the principal toxic components and molecular mechanism remain to be further elucidated. In this study, human lung adenocarcinoma A549 cells were treated with serial concentrations of water-extracted PM10 (WE-PM10) collected from Beijing, China. Our results showed that exposure to 25 and 50 µg/ml of WE-PM10 for 48 h significantly suppressed miR-26a to upregulate lin-28 homolog B (LIN28B), and in turn activated interleukin 6 (IL6) and signal transducer and activator of transcription 3 (STAT3) in A549 cells, subsequently contributing to enhanced epithelial-mesenchymal transition and accelerated migration and invasion. In vivo pulmonary colonization assay further indicated that WE-PM10 enhanced the metastatic ability of A549 cells. In addition, luciferase reporter assay demonstrated that 3' untranslated region of LIN28B was a direct target of miR-26a. Last but not the least, the key toxic contribution of metals in WE-PM10 was confirmed by the finding that removal of metals through chelation significantly rescued WE-PM10-mediated inflammatory, carcinogenic and metastatic responses. Taken together, miR-26a could act as the tumor suppressor in PM10-related lung cancer, and PM10-bound metals promoted lung cancer cell metastasis through downregulation of miR-26a that directly mediated LIN28B expression.

[Assessment of Ecosystem Health of Baogang Tailings Groundwater Based on Microbiome Index of Biotic Integrity (M-IBI)].

Index of Biological Integrity (IBI) is a scientific tool used to evaluate health of aquatic ecosystems. IBI associates anthropogenic influences with biological activity in the water body, and is formulated using data developed from biosurveys. Compared with other biotic assemblage indicators of water quality, little attention has been paid to the application of microbial community in ecosystem health assessment for groundwater bodies so far. An approach based on microbiome index of biotic integrity was developed to assess groundwater ecosystem health in this study. The method based on Illumina high-throughput DNA sequencing was applied to achieve the information of microbial community. The key environmental factors were selected based on CCA analysis and the optimized values were calculated for defining the taxonomic genera sensitive and resistant to these factors. The resulting candidate biotic factors were used to construct microbiome index of biotic integrity (M-IBI) evaluating system. The results showed among the studied sample sites from groundwater of Baogang rare earth tailings, 33.3% of samples were at "Great" level, 16.7% at "Good" level, most of samples (41.7%) at "moderate" level and 8.3% at "Bad" level. The ecosystem healthy status of the sample sites near the tailings was affected by human disturbances, while the samples far away the tailings were at healthy level. The results of the groundwater ecosystem healthy assessment based on M-IBI system had a good match with the groundwater quality standard based on chemical properties. It indicated that M-IBI could be a potential index to evaluate the health of groundwater ecosystem.

Conversion of food waste into biofertilizer for the biocontrol of root knot nematode by Paecilomyces lilacinus.

The feasibility of converting food waste into nematocidal biofertilizer by nematophagous fungus Paecilomyces lilacinus (P. lilacinus) was investigated. The culture conditions of P. lilacinus were optimized through response surface methodology. Results showed that fermentation time, the amount of food waste, initial pH and temperature were most important factors for P. lilacinus production. The P. lilacinus production under optimized conditions was 10(9.6 ± 0.3) conidia mL⁻¹. After fermentation, the chemical oxygen demand concentration of food waste was efficiently decreased by 81.92%. Moreover, the property evaluation of the resultant food waste as biofertilizer indicates its high quality with reference to the standard released by the Chinese Ministry of Agriculture. The protease activity and nematocidal ability of P. lilacinus cultured by food waste were 10.8% and 27% higher than those by potato dextrose agar, respectively.

Response mechanisms of antioxidants in bryophyte (Hypnum plumaeforme) under the stress of single or combined Pb and/or Ni.

The short-term responses and mechanisms of antioxidants in moss Hypnum plumaeforme subjected to single or combined Pb and/or Ni stress has been revealed in this study, in order to clarify (1) the relationship between the stress intensity and antioxidant fluctuation, (2) the difference between single and combined stress, and (3) the possibility of biomonitoring by the application of antioxidant fluctuation under stress. The results showed that the stress induced dose dependent formation of reactive oxygen species (ROS) and subsequent lipid peroxidation. Total chlorophyll (Chl) content and superoxide dismutase (SOD) activity were initiated under lower stress but were inhibited under higher stress. Both single and combined stress decreased catalase (CAT) activity but increased peroxidase (POD) activity, indicating POD in the moss played an important role in resisting the oxidative stress induced by Pb and Ni. The accumulation of (.)O2(-) and H2O2 in H. plumaeforme was respectively related to the low activity of SOD and the decreased activity of CAT. The study indicated that Pb and Ni had synergistic effect in inducing the oxidative stress in moss H. plumaeforme, especially under the combination of high concentration of Ni (0.1, 1.0 mM) and Pb. POD and CAT activity, as well as H2O2 and MDA content, which increased or decreased regularly with a dose dependent under Pb and Ni stress, could be used as an effective indicator in moss biomonitoring, especially in the case of light pollution caused by heavy metals without the changes in the appearance of mosses.