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Emerging evidence suggests that microRNAs (miRNAs) serve an important role in tumorigenesis and development. Although the low expression of miR‐125a‐5p in gastric cancer has been reported, the underlying mechanism remains unknown. In the current study, the low expression of miR‐125a‐5p in gastric cancer was verified in paired cancer tissues and adjacent non‐tumour tissues. Furthermore, the GC islands in the miR‐125a‐5p region were hypermethylated in the tumour tissues. And the hypermethylation was negatively correlated with the miR‐125a‐5p expression. Target gene screening showed that the histone methyltransferase Suv39H1 was one of the potential target genes. In vitro studies showed that miR‐125a‐5p could directly suppress the Suv39H1 expression and decrease the H3K9me3 levels. On the other hand, the Suv39H1 could induce demethylation of miR‐125a‐5p, resulting in re‐activation of miR‐125a‐5p. What is more, overexpessing miR‐125a‐5p could also self‐activate the silenced miR‐125a‐5p in gastric cancer cells, which suppressed cell migration, invasion and proliferation in vitro and inhibited cancer progression in vivo. Thus, we uncovered here that the epigenetic silenced miR‐125a‐5p could be self‐activated through targeting Suv39H1 in gastric cancer, suggesting that miR‐125a‐5p might be not only the potential prognostic value as a tumour biomarker but also potential therapeutic targets in gastric cancer.

We study silver nanowires as a model for the mechanical effects of ultrasonication. Their bending is caused by the outward push of shock waves against the inertia and fluid resistance. The structural analyses of a large number of cases reveal the principles of the mechanical effects on the freely suspended colloidal nanostructures. In addition to providing knowledge of the sonication effects, we believe that understanding would help to exploit sonication for nanoscale mechanical manipulation.

Altered expression of microRNA (miRNA) is strongly implicated in gastric cancer (GC). Here, we demonstrated a decreased expression of miRNA-329 in GC. Then we explored the regulatory mechanisms responsible for its effect on GC cells. GC tissues and their adjacent non-tumor tissues were collected. Complete follow-up was updated. A series of inhibitors, mimics, and siRNA against KDM1A were introduced to validate regulatory mechanisms for miR-497 and KDM1A in BGC-823 cells. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assay were employed for evaluating the expressions of miRNA-329, KDM1A, H3K4me1, and H3K4me2. Cell proliferation, cycle progression, and apoptosis were assessed by means of an MTT assay and flow cytometry. Cell colony formation was assessed. uman gastric cancer xenotransplanted into nude mice was studied. As opposed to adjacent tissues and gastritis tissues, miRNA-329 was highly expressed and KDM1A was low expressed in GC tissues. The patients with high miRNA-329 expression or low KDM1A expression had longer survival periods. The miRNA-329 mimics and siRNA against KDM1A decreased KDM1A expression and increased H3K4me1 and H3K4me2 expressions. Forced expression of miRNA-329 in gastric cancer cells significantly promotes their capacity of apoptosis but reduces proliferation, migration, and invasion. KDM1A is a direct downstream target for miRNA-329. In a nude mouse subcutaneous tumor system, in vivo tumor growth of BGC-823 was significantly inhibited after treatment of miRNA-329 mimics or siRNA against KDM1A. We conclude that miRNA-329 functions as a tumor suppressor in GC, which could be achieved via transcriptional suppression of KDM1A.

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It is now a consensus that high-stakes testing exerts powerful impact in controlling curriculum and pedagogy, and shaping students' learning. The power of testing is especially strong in contexts where testing culture prevails. The Chinese educational context is such a context which is dominated by competitive tests. The language testing results from large-scale tests, such as CET-4 (College English Test-Band 4), used to be included as a compulsory prerequisite for undergraduates to get their bachelor's degree. Such a requirement has been removed recently to reduce testing stakes for leverage purposes. Thus, it is worthwhile to investigate whether the change will possibly help to impact students and their learning in a positive way. Our study aimed to explore the impact of changes in the stakes of a language test in the Chinese university context. Data were collected through questionnaires from 544 College English students at a university in northwestern China. Our analysis via SPSS 2.3 showed that test-taking was still well accepted and practiced; while reducing the stakes helped to redirect the students towards English learning, it had less impact on their English learning motivation and approaches. The findings also show that the test-dominated environment that is deep-rooted in the macro-and micro-contexts decided the students' responses to this policy change.

Nano-stirbars are the most convenient and effective means for mixing in microscale systems. With electrospinning and ultrasonic breaking, a simple method is developed to continuously synthesize nano-stirbars without external magnet....

No abstract