RESUMO
Covalent organic frameworks (COFs) with donor-acceptor (D-A) units are credible photocatalysts for their per-designed structure, inherent porosity, large surface area, splendid stability and so forth. Developing COFs with an excellent photocatalytic efficiency for hydrogen evolution is of a great significance in alleviating the energy crisis. Herein, a D-A type imine-linked crystalline Zn-Por-TT COF was fabricated successfully via the co-polymerization of electron-deficient Zinc (II) 5,10,15,20-tetrakis(para-aminophenyl) porphyrin (Zn-TAPP), and electron-rich thieno[3,2-b]thiophene-2,5-dicarbaldehyde (TT). Profiting from the D-A complex structure, the obtained Zn-Por-TT COF showcases an excellent photocatalytic activity with a hydrogen evolution rate of 8200 µmol/g/h, while the Zn-TAPP monomer presents practically no capacity for the generation of hydrogen under identical conditions. In addition, the counterparts Por-TT COF and COF-366-Zn were employed to illustrate the enhancement of the photocatalytic performance by metal catalytic sites and D-A structures. In addition, the counterparts Por-TT COF and COF-366-Zn were employed to illustrate the enhancement of metal catalytic sites and D-A structures for the photocatalytic performance.
RESUMO
PURPOSE: To explore the function of DREAM gene mediated by NF-kB signal pathway in the pathogenesis of osteosarcoma. METHODS: This study included 13 Sprague Dawley (SD) rats with osteosarcoma (treatment group) and 13 healthy rats (control group). NF-kB, DREAM and P105 mRNAs expression levels were determined using quantitative PCR (qPCR). The expression levels of NF-kB, DREAM and P105 proteins were evaluated using ELISA and western blot. Also, DREAM protein expression in rats was determined by immunofluorescence. RESULTS: NF-kB and DREAM levels in the treatment group were significantly higher than those in the control group (p<0.05). However, P105 mRNA expression level in the treatment group was significantly lower than in the control group (p<0.05). Results obtained from ELISA and western blot showed that NF-kB and DREAM expression levels in the treatment group were significantly higher than in the control group (p<0.05). NF-kB and DREAM levels in the treatment group were 4.3±0.12 µg/l and 6.8±0.21 µg/l, respectively. These levels in the control group were 0.96±0.11 µg/l and 1.25±0.18 µg/l, respectively. P105 expression level in the treatment group was 0.37±0.11 µg/l which was significantly lower than that in the control group (1.63±0.21 µg/l) (p<0.05). Immunofluorescence results showed that DREAM expression level was significantly higher in the treatment group (p<0.05). CONCLUSION: NF-kB signal pathway promoted the expression of DREAM gene and also promoted the pathogenesis and worsening of osteosarcoma.
