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A novel cost-effective secondary hardening ultrahigh-strength steel, strengthened by the co-precipitation of M2C and NiAl, was developed. The present study systematically investigated the co-precipitation evolution, austenite reversion, and mechanisms of strengthening and toughening at different ageing temperatures. As the ageing temperature increased, the quenched microstructure underwent various transformations, including precipitation and dissolution of cementite, nucleation and coarsening of M2C and NiAl nanoparticles, as well as reversion of austenite. At ageing temperatures of 427 °C and 454 °C, a small amount of cementite was present in the martensite matrix, and M2C and NiAl precipitates started to form, resulting in low strength and poor toughness. At 482 °C, the peak-ageing stage was reached, achieving a maximum yield strength of 1875 ± 4 MPa and an ultimate tensile strength of 2185 ± 3 MPa. This strength is primarily attributed to shear strengthening of NiAl particles and Orowan strengthening of M2C carbides. Additionally, the complete dissolution of cementite at this stage improved toughness. As the ageing temperature increased to 510 °C and 538 °C, the strength decreased due to coarsening of M2C, while the toughness improved as a result of film austenite reversion and enhanced dislocations bypassing around the M2C carbides.

Meclicope pteleifolia is a traditional medicinal herb and edible plant in Southeast China. Here, we report the complete chloroplast genome of M. pteleifolia. The chloroplast genome is 159,012 bp in length with 38.33% GC content, containing a small single-copy (SSC) region (18,609 bp), a large single-copy (LSC) region (851 bp), and a pair of inverted repeats (IRs: 27,640 bp each). A total of 131 genes were predicted, including 84 protein-coding genes, 8 ribosomal RNA genes, 37 tRNA genes, and 2 pseudogenes. Phylogenetic analysis based on chloroplast genomes of 17 plant species shows that M. pteleifolia is closest to Zanthoxylum and Casimiroa. These complete chloroplast genomes can be subsequently used for researches of Rutaceae.

Pine needle oil from crude extract of pine needles has been used as an anti-cancer agent in Traditional Chinese Medicine. The α-pinene is a natural compound isolated from pine needle oil which has been shown anti-cancer activity. In previous study, we found that pine needle oil exhibited significant inhibitory effect on hepatoma carcinoma BEL-7402 cells. In this study, we investigate the inhibition of α-pinene on hepatoma carcinoma BEL-7402 cells in vitro and in vivo and further explore the mechanism. The results show that liver cancer cell growth was inhibited obviously with inhibitory rate of 79.3% in vitro and 69.1% in vivo, Chk1 and Chk2 levels were upregulated, CyclinB, CDC25 and CDK1 levels were downregulated.

Iodide (I-) is crucial to thyroid function, and its regulation in thyrocytes involves ion transporters and reactive oxygen species (ROS). However, the extent of 2Cl-/H+ exchanger (ClC-3) involvement in the iodide (I-) efflux from thyrocytes remains unclear. Therefore, we examined the effects of ClC-3 on I-efflux. ClC-3 expression was found to significantly alter the serum TT3 and TT4 concentrations in mice. We further found that excess I- stimulation affected ClC-3 expression, distribution, and I- efflux in FRTL-5 cells. Immunofluorescence analyses indicated that ClC-3 mainly accumulated in the cell membrane and co-localized with β-tubulins after 24 h of excess I- treatment, and that this process depended on ROS production. Thus, ClC-3 may be involved in I- efflux at the apical pole of thyrocytes via excess I--induced ROS production and β-tubulin polymerization. Our results reveal novel insights into the role of ClC-3 in I- transport and thyroid function. [ABSTRACT FROM AUTHOR]

FGF signaling pathway is imperative for definitive endoderm (DE) differentiation from human embryonic stem cells (hESCs), which always accompanies an epithelial-to-mesenchymal transition (EMT) process. However, whether there is an association between FGF signaling and the EMT during DE formation in vitro has remained elusive. In the present study, we identify that several FGF family members were significantly activated during the differentiation of hESCs toward DE. Inhibition of FGF signaling by an efficient and selective inhibitor BGJ398 abolishes both the EMT and DE induction by blocking the activation of the zinc-finger transcription factor SNAI1 which is a direct transcriptional repressor of cell adhesion protein CDH1. In addition, cell proliferation is also severely influenced by attenuating the FGF signaling. Collectively, we propose that the FGF signaling promotes the DE formation through mediating the EMT and cell proliferation. [ABSTRACT FROM AUTHOR]

Cell migration is crucial for tumor metastasis. Membrane ion channels may play a major role in tumor cell migration because the cells must undergo changes in shape and volume during migration. In the present study, we used the transwell migration assay, an in vitro model for cell migration, and the patch-clamp technique to investigate the role of the volume-activated Cl- current (Icl,vol) in the regulation of the migration of nasopharyngeal carcinoma CNE-2Z cells. 5-Nitro-2- (3-phenylpropylamino) benzoic acid (NPPB) inhibited the Icl,vol and the migration of CNE-2Z cells with almost identical dose-dependent pattern (IC50 of 98.1 μM and 97.7 μM for Icl,vol and cell migration, respectively). Extracellular adenosine triphosphate (ATP) also showed similar dose-dependent inhibitory effects on the currents and migration (IC50 of 1.07mM, and 1.11mM for Icl,vol and cell migration, respectively). Hypotonic treatments, which activated Icl,vol, increased cell migration. Exposure to hypertonic solutions, which was shown to suppress Icl,vol, inhibited cell migration. Replacement of Cl- with gluconate, which is relatively chloride channel-impermeable, impaired cell migration, whereas substitution of Cl- by I- and Br-, the chloride channel-permeable ions, did not significantly affect cell migration. Analysis of the effects of all the above treatments on Icl,vol and cell migration indicated that the inhibition of migration was positively correlated with the blockage of Icl,vol, with a correlation coefficient (r) of 0.97, suggesting a functional relationship between Icl,vol and cell migration. These data suggest that the volume-activated Cl- channels are involved in cell migration. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]