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Download ash and emission dust samples were collected from sintering, coking, ironmaking and steelmaking processes of iron and steel enterprises in Laiwu. Sixteen kinds of polycyclic aromatic hydrocarbons (PAHs) in the United States Environmental Protection Agency (USEPA) priority controlled lists were quantitatively analyzed using Gas Chromatography-Mass Spectrometer (GC-MS). Laser particle size analyzer was used to obtain the distribution pattern of download ash. It was found that the diameter distribution pattern from four production processes was quite different. The proportion of fine particulate (0–2.5 μm) was the highest (72.62%) in the steelmaking refining process, and was 28.962% in the ironmaking process. Moreover, the particle size in download ash from steelmaking refining is all less than 10 μm and that from the ironmaking process was 52.92%. The medium-sized particles (10–100 μm) were dominant in sinter and coking download ashes. The total PAHs (∑16PAHs) mass concentration ranged from 0.49 ± 0.06 to 69.63 ± 5.57 μg·g−1 in download ash samples, and varied from 2.815 ± 0.253 to 19.429 ± 2.545 μg·m−3 in emission dust samples. The ∑16PAHs values were both largest in download ash and dust emission from the coking process (69.63 ± 5.57 μg·g−1 and 19.429 ± 2.545 μg·m−3, respectively). The most abundant individual PAHs were benzo[b]fluoranthene, benzo[k]fluoranthene, phenanthrene, benzo[a]anthracene in ash samples, and benzo[a]anthracene, benzo[k]fluoranthene, benzo[b]fluoranthene and indeno[1,2,3-cd]pyrene in emission dust samples. Dominant compounds were high-molecular weight (four- to six-ring) PAHs in both ash and dust samples. The concentration order of individual compounds in PM10 and PM2.5 in ambient air around the steel plant was completely consistent with each other, and the concentration of ∑16PAHs was the highest in the steel plant and lowest in Daqin village because of upwind of the steel plant. The concentrations of benzo[b]fluoranthene and fluoranthene in ambient air were comparatively high, and were in accordance with the higher concentration of the two monomers in the download ash samples, which suggested that the effect of the emission flue gas from the steel plant on ambient air was necessary to concern. [ABSTRACT FROM AUTHOR]

Expression of miR-671 was reported to be downregulated in articular cartilage of patients with OA compared to healthy individuals, indicating it may serve as potential biomarker for OA. However, the mechanism by which miR-671 regulates the progression of OA remains unclear. Here, we aimed to investigate the role of miR-671 in cartilage from patients with OA. The expression of miR-671 and inflammation mediators in cartilage from patients with OA was analyzed by RT-PCR. In vitro , chondrocytes CHON-001 were stimulated with IL-1β for 24 h for OA model establishment. Protein expression of MMP-13, aggrecan, and collagen II was measured by western blot. In vivo , the severity of OA in mice was determined by histological analysis. We found that the level of miR-671 was downregulated in OA tissues, plasma and IL-1β treated CHON-001 cells, compared with control. MiR-671 mimics ameliorated IL-1β-induced proliferation inhibition and apoptosis stimulation, as well as decreased protein levels of collagen II and aggrecan in CHON-001 cells. In vivo study showed miR-671 mimics alleviated the progression of OA in mice. These results indicated miR-671 play an important role during the pathogenesis of OA. Therefore, miR-671 may serve as a potential therapeutic target for the treatment of OA. [ABSTRACT FROM AUTHOR]

Background: The E2A gene, which encodes two basic helix–loop–helix transcription factors, E12 and E47, regulates colorectal cancer progression and epithelial-mesenchymal transition. However, whether E2A regulates the tumor-initiating capacity of colorectal cancer is unclear. Thus, we have studied E2A expression in the initiation of colorectal cancer in vivo and in vitro. Methods: Immunohistochemistry and immunoblot were performed to determine protein levels of E2A in colorectal cancer specimens and cells. RNAi was employed to downregulate E2A expression, and the subsequent change in protein level was evaluated by immunoblot. Sphere-forming assay and enumeration of liver metastasis in mouse models were used to identify the tumor formation ability of colorectal cancer cells. Results: E2A expression in colorectal cancer clinical specimens was inversely associated with patients' progression-free survival. Functional studies demonstrated that E2A significantly decreased tumor formation in vitro and in vivo. Furthermore, nuclear translocation of beta-catenin and activation of the Wnt/beta-catenin pathway occurred after suppression of E2A in colorectal cancer cells. FoxM1 was identified as a down-stream target by mRNA microarray, implying that FoxM1 plays a main role in determining how E2A regulates the tumor-initiating capacity of colorectal cancer. Conclusion: E2A suppresses tumor-initiating capacity by targeting the FoxM1-Wnt/β-catenin pathway. [ABSTRACT FROM AUTHOR]

Bovine tuberculosis is a disease caused by Mycobacterium bovis (M. bovis) that leads to great economic losses in cattle production. The discovery of a reasonable bioagent to reduce M. bovis infection risk and environment contamination becomes significant and urgent. Previous study reported that human β-defensin-3 (HBD3) participated in Mycobacterial immunity and was recognized as a suitable candidate reagent. However, its minimal inhibitory concentration to M. bovis is not yet reported. In this study, we first purified HBD3 protein by recombinant-DNA technology and prokaryotic expression system. Subsequently, anti-bacterial tests were used to evaluate the basic bioactivity of the protein. Results revealed that recombinant HBD3 (rHBD3) protein inhibits Staphylococcus multiplication but not the host Escherichia coli. The growth curve of M. bovis showed that rHBD3 protein controls the proliferation of M. bovis in 20 μg/ml concentration. In addition, rHBD3 protein-incubated M. bovis exhibited reduced infectivity to alveolar epithelial cells and macrophages. In conclusion, the expression of rHBD3 protein is a potential ideal bio-regent for reducing M. bovis infection. [ABSTRACT FROM AUTHOR]

Efficient metal-free electrocatalysts for oxygen reduction reaction (ORR) are highly expected in future low-cost energy systems. We have successfully prepared crumpled, sheet-like, sulfur-doped graphene by magnesiothermic reduction of easily available, low-cost, nontoxic CO2 (in the form of Na2CO3) and Na2SO4 as the carbon and sulfur sources, respectively. At high temperature, Mg can reduce not only carbon in the oxidation state of +4 in CO32− to form graphene, but also sulfur in SO42− from its highest (+6) to lowest valence which was hybridized into the carbon sp2 framework. Various characterization results show that sulfur-doped graphene with only few layers has an appropriate sulfur content, hierarchically robust porous structure, large surface area/pore volume, and highly graphitized textures. The S-doped graphene samples exhibit not only a high activity for ORR with a four-electron pathway, but also superior durability and tolerance to MeOH crossover to 40% Pt/C. This is mainly ascribed to the combination of sulfur-related active sites and hierarchical porous textures, facilitating fast diffusion of oxygen molecules and electrolyte to catalytic sites and release of products from the sites. [ABSTRACT FROM AUTHOR]