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PurposeGlioblastoma multiforme (GBM) is one of the deadliest tumors, which is involved in numerous dysregulated microRNAs including miR-137. However, the mechanism of how miR-137 suppression associated with cancer progression and chemoresistance still remains to be elucidated.MethodsQuantitative reverse transcriptase-PCR (qRT-PCR), DNA methylation analysis, cell proliferation assay, flow cytometric analysis, invasion assay, in situ tumor formation experiment were performed to test the expression levels and functions of miR-137 in GBM. Bioinformatics analysis, luciferase reporter assay, qRT-PCR, immunoblotting, immunofluorescence, and immunohistochemistry assay were used to identify and verify the target of miR-137.ResultsWe found that miR-137 was downregulated in primary and recurrent GBM compared with normal brain tissues. Overexpression of miR-137 inhibited cell invasion and enhanced cell chemosensitivity to temozolomide (TMZ) by directly targeting low-density lipoprotein receptor-related protein 6 (LRP6) in GBM. Forced expression of LRP6 cDNA without its 3’-UTR region partly restored the effects of miR-137 in vitro and in vivo. Hypoxia-induced miR-137 methylation was responsible for the miR-137 suppression, leading to the cell chemoresistance and poor prognosis of GBM.ConclusionsThese findings demonstrated the detailed molecular mechanism of miR-137 in regulating GBM growth and chemoresistance in hypoxia microenvironment, suggesting the potentiality of miR-137 as a therapeutic target for GBM.

ObjectivesTo evaluate the associations of pre-endoscopy anxiety with discomfort and tolerance in patients undergoing unsedated esophagogastroduodenoscopy (EGD).MethodsThis is a hospital-based cohort study of 348 patients undergoing routine, non-advanced EGD without sedation. The primary outcomes were discomfort and tolerance. The anxiety before endoscopy was evaluated with a 10-point visual analogue scale (VAS). The associations of pre-endoscopy anxiety with the outcomes were evaluated with logistic regression adjusting for potential confounders like age, sex, and body mass index.ResultsSeventy patients reported severe discomfort and 56 patients reported poor tolerance after endoscopy. The risk of severe discomfort increased with pre-endoscopy anxiety and reached a platform around 7-10 points. Compared with the participants with low pre-endoscopy anxiety, those with moderate (adjusted odds ratio [OR] 2.70, 95% confidence interval [CI] 1.17 to 6.22) and high level of anxiety (adjusted OR 6.87, 95% CI 2.16 to 21.79) were associated with a gradual increase in the risk of severe discomfort (P-trend < 0.001). The association between pre-endoscopy anxiety and tolerance was linear, with an adjusted OR of 1.67(95% CI 1.33 to 2.08) for a 1-score increase in pre-endoscopy anxiety VAS. The associations were not modified by age, sex, pharyngitis, duration of endoscopy, and diameter of the endoscope.ConclusionsPre-endoscopy anxiety was an independent predictor of severe discomfort and poor tolerance in Chinese patients undergoing unsedated EGD. Our findings suggested the importance of the management of anxiety to reduce adverse endoscopic experience and taking high level of anxiety as an indication for sedation.

Doping and constructing intergrowth are found to be an effectual approach to modify the electrical properties of bismuth layer-structured ferroelectrics. In this work, ferroelectric, piezoelectric and dielectric properties of Nb-doped Bi4Ti3O12-SrBi4Ti4O15 (BTN-SBTN-x) intergrowth ceramics were investigated. The ferroelectric property of Bi4Ti3O12-SrBi4Ti4O15 was improved by niobium doping. The remanent polarization (2Pr) increases at first, then decreases with the increase of niobium content, while the coercive field changes little with Nb-doping. As niobium content is 0.06, the 2Pr maximizes at a value of 34.9 μC/cm2, which is increased by about 75% in comparison with that of Bi4Ti3O12-SrBi4Ti4O15 (2Pr = 20.0 μC/cm2). The Curie temperature of the samples varies hardly upon Nb-doping, which indicates that the good thermal stability of Bi4Ti3O12-SrBi4Ti4O15 is not deteriorated after Nb addition. Piezoelectric coefficient d33 was increased from 9.3 pC·N-1 to 18.6 pC·N-1 due to the enlargement of 2Pr. [ABSTRACT FROM AUTHOR]

An investigation on the ferroelectric and dielectric properties of higher-valent-cations Nb-and Mo-modificated SrBi4Ti4O15 ceramics was presented. The ferroelectric property of SrBi4Ti4O15 was both obviously improved by niobium and molybdenum doping. The remnant polarization (2Pr) of both Nb-and Mo-modificated SrBi4Ti4O15 increases at first, then decreases with further doping. As the doping content is 0.03 and 0.06 respectively, the 2Pr maximizes at a value of 24.7 μC/cm2 and 26.5 μC/cm2, which is about twice larger than that of SrBi4Ti4O15. Meanwhile, the coercive field is increased less than 20% upon Nb and Mo substitution. The Curie temperature of the samples shifted hardly by Nb-and Mo-doping, which indicates that the good thermal stability of SrBi4Ti4O15 is not affected. [ABSTRACT FROM AUTHOR]

Ferroelectric ceramics of lanthanum-modified SrBi 4 Ti 4 O 15 and Bi 4 Ti 3 O 12 -SrBi 4 Ti 4 O 15 have been synthesized, and Raman spectrum measurements have been carried out at room temperature. The investigation on the Raman spectra suggest that La 3+ ions prefer to occupy the A site in the case of x ≤ 0.10, and at higher content they tend to be incorporated into Bi 2 O 2 layers in the La-doped SrBi 4 Ti 4 O 15 . As for La-doped Bi 4 Ti 3 O 12 -SrBi 4 Ti 4 O 15 , the critical content of the doping ions is 0.50. An interesting phenomenon has been noticed that the remnant polarization maximized at about the critical doping content. Thus, it can be concluded that the Bi 2 O 2 layers have a very important effect on the properties in the bismuth layer-structured ferroelectric materials. [ABSTRACT FROM AUTHOR]

This article reports first-principles band structure calculations for RMn6Sn6 ( R=Tb, Dy). The calculation uses the linear muffin-tin orbitals (LMTO) method in the atomic-sphere-approximation (ASA), and yields results showing that both TbMn6Sn6 and DyMn6Sn6 are ferrimagnetic compounds with antiparallel aligned moments of R and Mn atoms. In this research the 4 f states of R atoms are treated as localized states, i.e., the hybridization of 4 f states with other valence electrons is neglected. The moments of Mn in both compounds were determined to be 2.43 μB and 2.38 μB, respectively. The considerably small additional moments for Mn from the spin-orbit coupling indicates that the spin-orbital coupling is not dominated for Mn atoms. The total moments of Tb and Dy atoms are 10.28 μB and 11.20 μB. All the calculation findings accorded well with experimental results. [ABSTRACT FROM AUTHOR]