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OBJECTIVE: To clarify the function of microRNA-15a in the spinal cord injury (SCI) and its potential mechanism. PATIENTS AND METHODS: The plasma levels of microRNA-15a and signal transducer and activator of transcription 3 (STAT3) in SCI patients were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between the expressions of microRNA-15a and STAT3 was analyzed. The in vitro SCI model was established in H2O2-induced C8-D1A and C8B4 cells, and in vivo SCI model was established in mice by hitting T10. The mRNA and protein expressions of tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6) were detected in the SCI model. The apoptosis was examined by flow cytometry or TUNEL staining, respectively. The motor function of mouse hindlimb was evaluated using the Basso Beattie Bresnahan (BBB) standard scale. The target gene of microRNA-15a was predicted by bioinformatics and further verified by dual-luciferase reporter gene assay. The expression changes of target genes in C8-D1A and C8B4 cells with microRNA-15a overexpression or knockdown were examined by qRT-PCR and Western blot. Finally, rescue experiments were performed to evaluate the regulatory effects of microRNA-15a and STAT3 on cell apoptosis. RESULTS: MicroRNA-15a was lowly expressed in plasma of SCI patients, while STAT3 was highly expressed with a negative correlation to microRNA-15a. Identically, microRNA-15a was lowly expressed in H2O2-induced C8-D1A and C8B4 cells, and STAT3 was highly expressed. MicroRNA-15a overexpression downregulated mRNA and protein levels of TNF-α and IL-6 in C8-D1A and C8B4 cells. BBB score was markedly low in SCI mice relative to controls. SCI mice injected with microRNA-15a mimics had higher BBB score than those injected with negative control. Besides, SCI mice with microRNA-15a overexpression had downregulated expressions of STAT3, TNF-α, and IL-6 in the impaired spinal cord tissues, as well as lower apoptotic rate. Through bioinformatics, we found binding sites between STAT3 and microRNA-15a. Their binding conditions were further verified by dual-luciferase reporter gene assay. Moreover, STAT3 expression was negatively regulated by microRNA-15a. Finally, rescue experiments showed that STAT3 overexpression could reverse the regulatory effects of microRNA-15a on expressions of TNF-α and IL-6, as well as apoptosis. CONCLUSIONS: MicroRNA-15a expression decreases in the SCI model, which participates in the process of SCI by regulating inflammatory response and cell apoptosis via targeting STAT3. [ABSTRACT FROM AUTHOR]

The crystal structure and polarization switching behavior of SrBi1.4La0.6Ta2O9 (SBLT) thin films have been studied by x-ray diffraction and piezoresponse force microscopy (PFM), respectively. Compared with SrBi2Ta2O9 (SBT), SBLT thin films show a reduced orthorhombic distortion. The polarization rotation of SBLT thin film, which is driven by negative and positive direct current (dc) biases, has been investigated by a combination of vertical and lateral PFM (VPFM and LPFM, respectively). After dc bias applications, the VPFM image is hardly changed, whereas the LPFM image experiences an obvious variation. It is believed that such difference is caused by 90° polarization switching. However, this kind of switching can be only realized by the exchange of a axis and b axis. By virtue of the reduced orthorhombic distortion, the a-b exchange in SBLT is easier than that in SBT. Unfortunately, stress is created due to the 90° polarization switching in SBLT thin films. The internal stress is found to increase with the repeated switching cycles, and so the polarization reorientation in SBLT is constrained. Thus, the fatigue resistance of SBLT thin films is not thought to be as good as that of SBT. [ABSTRACT FROM AUTHOR]

A combination of piezoresponse force microscopy and x-ray diffraction sin2 Ψ stress measurement have been used to investigate domain evolutions in (111)-oriented Pb(Zr0.55Ti0.45)O3 (PZT) and (115)-oriented SrBi2Ta2O9 (SBT) thin films with the repeated switching cycles sfatigue processd. In the PZT film, it has been found that 90° a-c domain walls form at the beginning of fatigue process and increase in amount with accumulation of switching cycles, accompanied by increase of stress. However, domain pattern and stress in the SBT film seem to be unchanged as the fatigue process is going on. The increase in stress with the repeated switching cycles in the PZT film can be attributed to the lattice distortion caused by polarization rotation. On the contrary, polarization switching in SBT involves little lattice distortion and lets it in a nearly stress-free status during the fatigue process. The difference in domain evolution during the fatigue process suggests the important role of stress in fatigue behaviors of PZT and SBT films. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Lung cancer is a malignant tumor with extremely high morbidity and mortality. Recent studies have identified the vital role of LINC00511 (lncRNAs) in the development and progression of non-small cell lung cancer (NSCLC). In this research, we aim to explore the biological function of LINC00511 in the development and metastasis of NSCLC. PATIENTS AND METHODS: LINC00511 expression in 57 paired NSCLC patients' tissues and matched normal tissues were detected by Real-time quantitative polymerase chain reaction (RT-qPCR). Cell proliferation assay, colony formation assay and transwell assay were conducted to observe the biological behavior changes of NSCLC cells through the influence of LINC00511. In addition, dual-luciferase reporter gene assay, RNA immunoprecipitation assay (RIP) and, chromatin immunoprecipitation (ChIP) were performed to discover the potential targets of LINC00511 in NSCLC cells. RESULTS: LINC00511 was highly expressed in NSCLC tissues and cell lines compared with controls. LINC00511 expression was positively correlated with tumor size, tumor stage, lymph node metastasis and distant metastasis, but negatively correlated with overall survival (OS) of NSCLC patients. Receiver Operating Characteristic (ROC) curves suggested that LINC00511 could be an effective indicator to distinguish NSCLC patients from normal people. Cell counting kit-8 (CCK-8), flow cytometry and transwell assay showed that knockdown of LINC00511 in A549 cells decreased viability, accelerated apoptosis and inhibited invasive and migratory abilities. Overexpression of LINC00511 in PC9 cells obtained the opposite biological effects. Chromatin fractionation predicted that LINC00511 was mainly distributed in the nucleus. RIP and ChIP assay showed that LINC00551 directly bound to lysine-specific demethylase 1 (LSD1) and enhancer of zeste homolog 2 (EZH2). It inhibited expressions of LATS2 and KLF2 by binding to their promoter regions. CONCLUSIONS: LINC00511 is upregulated in NSCLC tissues and cell lines. It is closely related to tumor size, tumor stage, lymph node metastasis and, distant metastasis of NSCLC patients. Knockdown of LINC00511 attenuates proliferative, migratory and invasive capacities, but induces apoptosis of NSCLC cells. LATS2 and KLF2 are target genes of LINC00511, which are regulated by LINC00511 through binding to EZH2 and LSD1, thus influencing the progression of NSCLC. [ABSTRACT FROM AUTHOR]

The brazed grinding wheels were fabricated by high-frequency induction brazing with varying temperature from 900 to 1000 °C. The morphology and chemical composition of the brazing resultants around cubic boron nitride (cBN) grit were examined using scanning electron microscopy (SEM) and energy dispersion X-ray spectrometry (EDS) techniques. Grinding tests of titanium alloy Ti6Al4V were carried out. The results showed that the reaction layer composed of Ti-N and Ti-B compound was formed between the cBN grit and filler alloy. The specific grinding force and specific grinding energy of brazed cBN wheels were much lower than those of the electroplated counterpart during grinding of titanium. In particular, a good sharpness and bonding strength of brazed cBN wheel were obtained when the brazing temperature is 940 °C. With the brazing temperature increase, the main wear pattern of brazed cBN wheel is pullout, breakage, and crush, successively, while adhesion is dominant on the surface of the electroplated cBN wheel. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Given the important functions of TP53 pathway in various biological processes, this study aimed to investigate the expression of TP53 pathway-related proteins in ovarian carcinoma transplanted subcutaneously in nude mice with and without the presence of p53 inhibitor and to explore possible roles of p53 in the development of ovarian cancer. MATERIALS AND METHODS: Thirty BALB/cnu female nude mice were randomly divided into model group, control group and p53 inhibitor group (Pftα group). There were 10 rats in each group. The nude mice were subcutaneously inoculated with human ovarian cancer cell line SKOV3, and the tumor growth was observed. Morphological changes of tumor tissue were observed by hematoxylin and eosin (HE) staining. The mRNA and protein levels of TP53 pathway related factors-p53, p21 and mouse double minute 2 homolog (MDM2) were detected by RT-PCR and Western blot. RESULTS: p53 inhibitor can increase the growth rate of subcutaneously transplanted tumor in nude mice. p53 inhibitor could decrease the expression of p53 and p21 at both mRNA and protein levels and increase the expression of MDM2 at both mRNA and protein levels in ovarian carcinoma transplanted subcutaneously in nude mice. CONCLUSIONS: TP53 pathway may play pivotal roles in the development of ovarian cancer and TP53 pathway may be a new target for the treatment of ovarian cancer. [ABSTRACT FROM AUTHOR]

The physical properties of CdS is calculated by using the first principles pseudopotential plane wave method based on density functional theory (DFT). The calculated lattice parameters and elastic constants agree well with other theoretical values, and the crystal is determined to be structurally stable by the Born mechanical stability condition. The Debye temperature, Grüneisen parameters, heat capacity and thermal expansion coefficient of CdS under high temperature and high pressure were studied successfully by using the quasi-harmonic Debye model. The influence of pressure on thermal expansion coefficient and Debye temperature is greater than that of temperature. The heat capacity decreases with the increase of pressure. At high temperature and high pressure, the heat capacity approaches the Dulong-Petit limit. [ABSTRACT FROM AUTHOR]

Exotic domain states, like vortex, offer the promise of superior properties and the potential disclination strain is a key factor for their formation in ferroelectrics. Here we show that large scale arrays of four-state vortex domains can be obtained in rhombohedral BiFeO3 thin films grown on PrScO3 substrates by pulsed laser deposition. Cs-corrected scanning transmission electron microscopy demonstrates that each vortex domain is comprised of four ferroelectric variants with two 180° domain walls and two 109° domain walls. Atomic mappings of the lattice distortions unit cell by unit cell reveal that the cores of the vortex might be charged. The strains are mainly concentrated on domain walls. The formation mechanism of such large scale vortex-like states was discussed. [ABSTRACT FROM AUTHOR]