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ZIF-67/CNT materials are prepared by using in situ growth method with cobalt nitrate and 2-methylimidazole (2-MI) as raw materials, polyvinyl pyrrolidone (PVP) as complexing agents. A series of N-Co@C/CNT catalysts are prepared through heating ZIF-67/CNT in N2 atmosphere. The effects of additional proportion of CNT on the catalytic performance of N-Co@C/CNT catalysts for oxygen reduction reaction (ORR) are studied. The chemical states of the materials, micro-morphology, elemental composition, and crystalline structure are analyzed by X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), transmission electron microscope (TEM), and X-ray diffraction (XRD). The results show that polyhedral ZIF-67 has grown on the surfaces of CNTs. After heat treatment, ZIF-67/CNT transforms to N-Co@C/CNT. The particle size of Co is 10–20 nm. N-Co@C/CNT-2.6 shows the best catalytic performance for ORR in alkaline solution with the onset potential of 0.94 V, half-wave-potential of 0.83 V, and limiting diffusion current density of 5.6 mA cm−2. The ORR on N-Co@C/CNT proceeds through a four-electron path and the yield of H2O2 is 12%, which is close to Pt/C. N-Co@C/CNT shows higher methanol-tolerant ability than Pt/C. The addition of CNT makes N-Co@C expose more active sites. CNT plays an important role in connecting different N-Co@C particles and enhancing the electron conductivity. The contents of graphitic nitrogen and pyridine nitrogen in N-Co@C/CNT-2.6 catalysts are 15.8% and 38.6%, respectively, which are higher than those in N-Co@C (7% and 34%).

Co/NC-Gr catalyst is prepared by in-situ growth of porous ZIF-67 on graphene (Gr) sheets followed by calcination. The effect of preparation method on the structure and catalytic performance of Co/NC-Gr for oxygen reduction reaction is studied. By optimizing the preparation process, the large Gr sheets are wrapped around the surfaces of the Co-incorporated polyhedral N-doped carbon skeleton. This structure plays a great role in connecting different Co/NC rhombic dodecahedron (RD), leading to high conductivity and fast mass transportation. The higher-content of pydinic-N and graphitic-N in Co/NC-Gr-A than those in Co/NC make it have enhanced catalytic activity. The porous Co/NC-Gr-A shows the highest ORR activity and stability through a dominant 4e− process. The Co/NC-Gr-A exhibits much higher methanol-tolerant ability than Pt/C. The yield of H2O2 during ORR on Co/NC-Gr-A is very close to that on commercial Pt/C.

The emerging evidence reveals that protein arginine methyltransferase 5 (PRMT5) is involved in regulation of tumour cell proliferation and cancer development. Nevertheless, the exact role of PRMT5 in human lung cancer cell proliferation and the underlying molecular mechanism remains largely obscure. Here, we showed that PRMT5 was highly expressed in human lung cancer cells and lung cancer tissues. Furthermore, we generated PRMT5 stable knockdown cell lines (A549 and H1299 cells) and explored the functions of PRMT5 in lung cancer cell proliferation. We found that the down‐regulation of PRMT5 by shRNA or the inhibition of PRMT5 by specific inhibitor GSK591 dramatically suppressed cyclin E1 and cyclin D1 expression and cell proliferation. Moreover, we uncovered that PRMT5 promoted lung cancer cell proliferation via regulation of Akt activation. PRMT5 was directly co‐localized and interacted with Akt, but not PTEN and mTOR. Down‐regulation or inhibition of PRMT5 markedly reduced Akt phosphorylation at Thr308 and Ser473, whereas the expression of PTEN and mTOR phosphorylation was unchanged, indicating that PRMT5 was an important upstream regulator of Akt and induced lung cancer cell proliferation. Altogether, our results indicate that PRMT5 promotes human lung cancer cell proliferation through direct interaction with Akt and regulation of Akt activity. Our findings also suggest that targeting PRMT5 may have therapeutic potential for treatment of human lung cancer.

During recent years, increasing demand of new, clean, and renewable energy resources has stimulated wide study on exploitation of non-platinum-group cathode catalysts for oxygen reduction reaction (ORR). Here, a series of nitrogen-doped carbon coated Co nanoparticle supported on reduced graphene oxide (Co@NC/RGO) were prepared by growth of ZIF-67 on GO with subsequent carbonation. The influence of incorporating dose of GO on the catalyst structure and activity was studied. The phase structure, morphology, element distribution, element composition, specific surface area, and pore-size distribution were characterized by various characterization techniques. The highest catalytic performance is achieved when the adding proportion of GO is 2.6% with the onset potential of 0.96 V and half-wave potential of 0.82 V. The introduction of RGO not only improves the electronic conductivity but also accelerates charge transfer. The special porous structure makes it have high specific surface area (313.7 m2 g−1) and large pore size (12.6 nm). The contents of pyridinic-N (53.4%) and graphitic-N (19.3%) in Co@NC/RGO-2.6 are higher than those in Co@NC (50.2% and 10.3%). Co@NC/RGO-2.6 exhibits much higher durability than commercial Pt/C. The ORR mechanism on the home-made catalyst is similar to that on Pt/C.

Due to the diversity of the image content, different images have different focuses, image retrieval system based on single feature has a lower performance, and it cannot apply to all images, so an image retrieval method using multi-feature fusion is proposed. In this method, the color moment in RGB color space in combination with the color histogram in HSV color space is used for color feature extraction, the improved Zernike moments are used for shape feature extraction, and the gray level co-occurrence matrix is used for texture feature extraction, then combining these three features. Finally, respectively using color features, shape features, texture features as well as the fused features for image retrieval, the experimental results show that the image retrieval method based on multi-feature fusion has better retrieval performance.

Polychlorinated biphenyls (PCBs) possessed much potential hazard to environment because of its chemical stability and biological toxicity. Here, we identified the binding mode of a representative compound, PCB153, to human serum albumin (HSA) using fluorescence and molecular dynamics simulation methods. The fluorescence study showed that the intrinsic fluorescence of HSA was quenched by addition of PCB153 through a static quenching mechanism. The thermodynamic analysis proved the binding behavior was mainly governed by hydrophobic force. Furthermore, as evidenced by site marker displacement experiments using two probe compounds, it revealed that PCB153 acted exactly on subdomain IIIA (site II) of HSA. On the other hand, the molecular dynamics studies as well as free energy calculations made another important contribution to understand the conformational changes of HSA and the stability of HSA-PCB153 system. Molecular docking revealed PCB153 can bind in a large hydrophobic activity of subdomain IIIA by the hydrophobic interaction and hydrogen bond interactions between chlorine atoms and residue ASN391. The present work provided reasonable models helping us further understand the transporting, distribution and toxicity effect of PCBs when it spread into human blood serum.

For centuries, Patrinia heterophylla had been used in China to treat many diseases including tumor. Triterpenes has been identified as the major active constituents in Patrinia heterophylla. To elucidate the antitumor mechanism of triterpenes from Patrinia heterophylla1 (TPH), a proteomic analysis is carried out with TPH treatment in K562 cells. The total proteins extracted from TPH treated K562 cells are analyzed by two dimensional gel electrophoresis (2-DE) and compared with those untreated K562 cells. Mass spectrometry is applied to identify the differentially expressed proteins. Twenty-three differentially expressed significant proteins are discovered. Eight proteins are later identified by mass spectrometry (MALDI-TOF-MS) and Mascot software. Among them, four proteins are up-regulated (Aldolase A, Glyceraldehyde-3-phosphate dehydrogenase, Flavin reductase and Hemoglobin subunit) and four proteins were down-regulated (Heat-shock protein 90 〈Alpha〉 (HSP90-〈Alpha〉), Eukaryotic translation initiation factor 5A, Moesin, tublin) by TPH treatment in K562 cells. The identified proteins are associated with energy metabolism, oxidative stress, apoptosis, signal transduction, differential induction, and protein biosynthesis. These findings might provide valuable insights into the antitumor mechanism of TPH in K562 cells.

To investigate the effects of advanced oxidation protein products (AOPP) on epithelial-to-mesenchymal transition (EMT) in cultured human proximal tubular epithelial cells (HK-2) and explore the mechanism.HK-2 cells treated with 50, 100, 200, and 400 µg/ml AOPP or 50 µg/m bovine serum albumin (BSA) for 24 h, or with 200 µg/ml AOPP for 0.5, 1, 3, 6, 12, and 24 h were examined for the protein expression of α-SMA and E-cadherin. In cells pretreated with diphenyleneiodonium (DPI) or cytoplasmic superoxide dismutase (C-SOD), the effects of 50 µg/ml BSA and 200 µg/ml AOPP were assessed on the expressions of α-SMA and E-cadherin, malondialdehyde (MDA) level, superoxide dismutase (SOD) activity, catalase (CAT) activity, and glutathione peroxidase (GSH-px) activity.AOPP treatment up-regulated α-SMA expression and down-regulated E-cadherin expression in a dose- and time-dependent fashion. AOPP exposure of the cells resulted in increased MDA level and lowered activities of SOD, CAT and GSH-PX. DPI and C-SOD partially attenuated the effects of AOPP on α-SMA, E-cadherin, MDA, SOD, CAT and GSH-px.AOPP can induce EMT in cultured HK-2 cells via oxidative stress, and this effect can be attenuated by inhibiting the activation of NADPH oxidase and using antioxidants to delay the progression of renal interstitial fibrosis.

To investigate the association between single nucleotide polymorphisms (SNPs) of the transmembrane protein 39A (TMEM39A) at the loci 1880G/A, 2442T/G, and 2456A/T and systemic lupus erythematosus (SLE) in Chinese Han patients.TMEM39A gene polymorphisms at 3 loci (1880G/A, 2442T/G, 2456 A/T) were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 110 Chinese Han patients with SLE and 80 normal control subjects, and the allele and genotype frequencies were compared by Chi-square test between the two groups.Both the genotype frequencies (AA, GA and GG) and allele frequencies (A and G) at 1880G/A differed significantly between SLE cases and the normal controls (P=0.002 and P=0.044, respectively). The two groups also showed significant differences in the genotype frequencies (GG, TG and TT) (P=0.001) and allele frequencies (G and T) (P=0.041) at 2442T/G. No significant differences were found in the genotype frequencies (TT, AT and AA) or allele frequencies (T and A) at 2456A/T between the two groups (P0.05). The allele and genotype frequencies of the 3 SNPs showed no significant differences between lupus nephritis (LN) patients and non-LN patients.The TMEM39A polymorphisms at 1880G/A and 2442T/G, but not at 2456 A/T gene, may be associated with the susceptibility to SLE in Chinese Han population. The genotype or allele frequencies of the 3 SNPs have no effect on the incidence of lupus nephritis.

A series of eight novel podophyllotoxin derivatives were designed, synthesized and evaluated for biological activities. The antiproliferative activities were tested against a panel of human cancer cell lines (K562, SGC, Hela and HepG) and the inhibition of tubulin polymerization was also evaluated. Compound 8e displayed significant antiproliferative activities for all four cell lines and strong levels of tubulin polymerization inhibition effect. Combined with cell apoptosis and cell cycle analysis, it demonstrated that compound 3e that effectively interfere with tubulin dynamics prevent mitosis in cancer cells, leading to cell cycle arrest and, eventually dose dependent apoptosis. All experimental measurements were also supported by molecular docking simulations of colchicine binding site, which revealed the governing forces for the binding behavior and a good relationship with anti-tubulin activity and antiproliferative activities. The synthesis and biological studies provided an interesting new class of antitubulin agents for development of lead compounds and also a direction for further structure modification to obtain more potent anti-cancer drugs.

Microtubules are considered as important targets of anticancer therapy. Podophyllotoxin and its structural derivative are major microtubule-interfering agents with potent anticancer activity. In this study, we reported the anticancer effects of 10 representative podophyllotoxin derivatives on a panel of four human cancer cell lines. Deoxypodophyllotoxin (6b) and β-apopicropodophyllotoxin (6g) elicited strong antiproliferative effects (IC₅₀) at a range of 0.0073-0.14 μM. Direct tubulin depolymerization assay in vitro was also performed. Results showed that that the two compounds can inhibit microtubule polymerization. Experimental measurements were also supported by molecular dynamic simulations, which showed that the two active compounds formed interactions with the colchicine-binding site of the tubulin protein. Our results helped us understand the nature of tubulin binding and determine the core design of a new series of potent inhibitors of tubulin polymerization.

Oxidative damage of biomolecules increases with age and is postulated to be a major causal factor of various physiological function disorders. Consequently, the concept of anti-age by antioxidants has been developed. Lycium barbarum fruits have been used as a traditional Chinese herbal medicine and the data obtained in in vitro models have clearly established the antioxidant potency of the polysaccharides isolated from the fruits. In the present study, the age-dependent changes in the antioxidant enzyme activity, immune function and lipid peroxidation product were investigated and effect of Lycium barbarum polysaccharides on age-induced oxidative stress in different organs of aged mice was checked. Lycium barbarum polysaccharides (200, 350 and 500 mg/kg b.w. in physiological saline) were orally administrated to aged mice over a period of 30 days. Aged mice receiving vitamin C served as positive control. Enzymatic and non-enzymatic antioxidants, lipid peroxides in serum and tested organs, and immune function were measured. Result showed that increased endogenous lipid peroxidation, and decreased antioxidant activities, as assessed by superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and total antioxidant capacity (TAOC), and immune function were observed in aged mice and restored to normal levels in the polysaccharides-treated groups. Antioxidant activities of Lycium barbarum polysaccharides can be compable with normal antioxidant, vitamin C. Moreover, addition of vitamin C to the polysaccharides further increased the in vivo antioxidant activity of the latter. It is concluded that the Lycium barbarum polysaccharides can be used in compensating the decline in TAOC, immune function and the activities of antioxidant enzymes and thereby reduces the risks of lipid peroxidation accelerated by age-induced free radical.