Three-dimensional (3D) hierarchically porous nanostructures with controlled morphology and dimensionality represent one kind of important material and have received enormous attention for a series of applications. In this work, 3D hierarchically porous ZnO architectures were synthesized via an amino acid-assisted biomimetic hydrothermal method combined with subsequent calcination. First a basic zinc carbonate (BZC) precursor with a lamellar spherical morphology assembled by interconnected nanosheets was synthesized. By subsequent calcination, the as-obtained BZC precursor can be facilely transformed into porous ZnO with a large surface area of 193.7 m 2 /g, while maintaining its 3D hierarchical morphology. The 3D hierarchically porous ZnO superstructures are further employed as a support to load Au nanoparticles (AuNPs) to construct hybrid nanomaterials for chemical gas sensors. The AuNP-functionalized 3D hierarchically porous ZnO nanomaterials, combining the high surface accessibility of porous materials and catalytic activity of small AuNPs, demonstrated excellent sensor properties in terms of higher sensitivity and very fast response. Furthermore, it is expected this AuNP-functionalized 3D hierarchically porous nanostructure may provide a new pathway to develop advanced nanomaterials for applications like gas sensors, low temperature CO oxidation and photocatalysis.

Astrocyte elevated gene-1 (AEG-1), upregulated in various types of human cancers, has been reported to be associated with the carcinogenesis of human cancer. However, the functional significance of AEG-1 in human esophageal squamous cell carcinoma (ESCC) remains unknown. In the present study, we showed the expression of AEG-1 was markedly upregulated in esophageal cancer cell lines and surgical ESCC specimens at both transcriptional and translational levels. Immunohistochemical analysis revealed that 80 of 168 (47.6%) paraffin-embedded archival ESCC specimens exhibited high levels of AEG-1 expression. Statistical analysis suggested the upregulation of AEG-1 was significantly correlated with the clinical staging of the ESCC patients (P 5 0.001), T classification (P 5 0.002), N classification (P 5 0.034), M classification (P 5 0.021) and histological differentiation (P 5 0.035) and those patients with high AEG-1 levels exhibited shorter survival time (P < 0.001). Multivariate analysis indicated that AEG-1 expression might be an independent prognostic indicator of the survival of patients with ESCC. Furthermore, we found that ectopic expression of AEG-1 in ESCC cells could significantly enhance cell proliferation and anchorage-independent growth ability. Conversely, silencing AEG-1 by short hairpin RNAi caused an inhibition of cell growth and anchorage-independent growth ability on soft agar. Moreover, we demonstrated that the upregulation of AEG-1 could reduce the expression of p27 Kip1 and induce the expression of cyclin D1 through the AKT/FOXO3a pathway. Our findings suggest that the AEG-1 protein is a valuable marker of ESCC progression and that the upregulation of AEG-1 plays an important role in the development and pathogenesis of human ESCC.

Polypyrrole-coated SnO 2 hollow spheres hybrid materials have been synthesized through an in situ polymerization of pyrrole monomers in the presence of preprepared SnO 2 hollow spheres. The hybrids were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR), and thermogravimetric analysis (TG). Experimental data showed certain synergetic interaction existed in the hybrids, probably resulting in the enhanced thermal stability of polypyrrole coatings. Gas sensing tests showed that the hybrids possessed very fast response and high sensitivity to ammonia gas at room temperature, implying its potential application for gas sensors.

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