Highly stable dispersions of nanosized copper particles with an average particle size less than 2 nm were synthesized using a straightforward, cost-effective, and green method. Nontoxic L-ascorbic acid was utilized as both a reducing agent and capping agent precursor in aqueous medium. The copper particles were characterized by ultraviolet-visible spectroscopy, transmission electron microscopy, and Fourier-transform infrared spectroscopy The mechanism of L-ascorbic acid on the reduction and stabilization of copper nanoparticles is also discussed.

Co 3 O 4 is a well-known catalyst in the oxidation reaction. In such a catalyst, the geometric and electronic structures of tetrahedrally coordinated Co 2+ and octahedrally coordinated Co 3+ can be regulated by directional metal ion substitution strategy, accompanied by the modification of catalytic activity. Herein, normal and inverse cobalt-based spinel catalysts M x Co 3−x O 4 (M = Zn and Ni) with a threedimensionally ordered macroporous (3DOM) structure were successfully fabricated through the carboxy-modified colloidal crystal templating (CMCCT) method. The relationship between the dopant and activity during NO x -assisted soot oxidation was systematically studied by means of XPS, H 2 -TPR, soot-TPR, isothermal anaerobic titrations, NO-TPO, soot-TPO, and so on. The well-defined 3DOM structure for M x Co 3−x O 4 catalysts can improve the contact efficiency of soot and catalysts. 3DOM NiCo 2 O 4 exhibits high catalytic activity for soot oxidation under a loose contact mode between soot and catalyst. For instance, its T 50 and TOF values are 379 °C and 1.36 × 10 −3 s −1 , respectively. The doping of Ni to Co 3 O 4 will induce the structural distortion, improve the density of oxygen vacancies, and enhance lattice oxygen mobility. It leads to more surface-active oxygen species. A vacancy-mediated pathway of NO oxidation on the spinel catalyst is proposed according to the experimental results of in situ DRIFT spectra, in situ Raman spectra, and the theoretical knowledge of coordination chemistry of metal−NO. The catalytic performance of soot oxidation is highly related to the capacity of a catalyst in oxidizing NO to NO 2 . Therefore, indirect NO 2 -assisted mechanism is proposed for soot oxidation under an NO/O 2 /N 2 atmosphere.

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3D ordered meso-macroporous (3DOMM) Ce0.2Zr0.8O2 (CZO) was successfully synthesized by a combined method of evaporation-induced interfacial self-assembly (EISA) and colloidal crystal templates (CCT). The multifunctional catalysts of spinel-type Pd x Co3–x O4 nanoparticles (NPs) supported on 3DOMM CZO were fabricated by a gas bubbling assisted coprecipitation (GBCP) method. The relationship between nanostructure (hierarchical pore and spinel-type active phase) and activity during catalytic soot oxidation was studied by the techniques of SEM, TEM, XPS, H2-TPR, NO oxidation, soot-TPO, and so on. The 3DOMM structure with a larger surface area and total pore volume increases the amount of supported active sites and enhances the contact efficiency between reactants (soot, O2, and NO) and catalysts. Spinel-type Pd x Co3–x O4 (AB2O4) binary active sites by substitution for Co2+ (A site) with Pd2+ cations are beneficial for improving activation efficiency for gaseous reactants (NO and O2). The novel nanocatalysts of 3DOMM CZO-supported spinel-type Pd x Co3–x O4 NPs exhibited superb catalytic performance and strong nanostructure-dependent activity for soot oxidation under loose contact of soot with catalyst. For instance, the T 10, T 50, and T 90 values of 3DOMM PdCo2O4/CZO catalyst with the highest catalytic activity (TOF = 2.56 h–1) are only 313, 367, and 404 °C, respectively. The NO2-assisted catalytic mechanism for soot oxidation is studied and proposed by in situ Raman spectra, and the role of spinel-type PdCo2O4 binary active sites is revealed. 3DOMM Pd x Co3–x O4/CZO catalysts are decent systems for soot oxidation, and the easy preparation technology has the potential for application to catalysts with other element compositions.

Transfer RNAs (tRNAs), traditionally considered to participate in protein translation, were interspersed in the entire genome. Recent studies suggested that dysregulation was observed in not only tRNAs, but also tRNA derivatives generated by the specific cleavage of pre- and mature tRNAs in the progression of cancer. Accumulating evidence had identified that certain tRNAs and tRNA derivatives were involved in proliferation, metastasis and invasiveness of cancer cell, as well as tumor growth and angiogenesis in several malignant human tumors. This paper reviews the importance of the dysregulation of tRNAs and tRNA derivatives during the development of cancer, such as breast cancer, lung cancer, and melanoma, aiming at a better understanding of the tumorigenesis and providing new ideas for the treatment of these cancers.

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MicroRNA-381 (miR-381) is a highly expressed onco-miRNA that is involved in malignant progression and has been suggested to be a good target for glioblastoma multiforme (GBM) therapy. In this study, we employed two-dimensional fluorescence differential gel electrophoresis (2-D DIGE) and MALDI–TOF/TOF-MS/MS to identify 27 differentially expressed proteins, including the significantly upregulated neurofilament light polypeptide (NEFL), in glioblastoma cells in which miR-381 expression was inhibited. We identified NEFL as a novel target molecule of miR-381 and a tumor suppressor gene. In human astrocytoma clinical specimens, NEFL was downregulated with increased levels of miR-381 expression. Either suppressing miR-381 or enforcing NEFL expression dramatically sensitized glioblastoma cells to temozolomide (TMZ), a promising chemotherapeutic agent for treating GBMs. The mechanism by which these cells were sensitized to TMZ was investigated by inhibiting various multidrug resistance factors (ABCG2, ABCC3, and ABCC5) and stemness factors (ALDH1, CD44, CKIT, KLF4, Nanog, Nestin, and SOX2). Our results further demonstrated that miR-381 overexpression reversed the viability of U251 cells exhibiting NEFL-mediated TMZ sensitivity. In addition, NEFL-siRNA also reversed the proliferation rate of U251 cells exhibiting locked nucleic acid (LNA)-anti-miR-381-mediated TMZ sensitivity. Overall, the miR-381-NEFL axis is important for TMZ resistance in GBM and may potentially serve as a novel therapeutic target for glioma.