To explore the effects of micro ribonucleic acid (miR)-188 on proliferation and apoptosis of lung adenocarcinoma (LUAD) cells, and its potential mechanism.
The expression level of miR-188 in LUAD ...cell lines was detected via quantitative Real Time-Polymerase Chain Reaction (PCR). The effects of miR-188 overexpression on proliferation and apoptosis of A549 cells were detected using methyl thiazolyl tetrazolium (MTT) assay, colony formation assay, and flow cytometry. The potential targets for miR-188 were predicted using the TargetScan Human database, and the interaction between miR-188 and target gene was determined through Dual-Luciferase reporter assay. Moreover, the associations of miR-188 and sine oculis homeobox homolog 1 (SIX1) with the extracellular signal-regulated kinase (ERK) pathway were detected via Western blotting.
The expression of miR-188 significantly declined in LUAD cell lines (p<0.05). The overexpression of miR-188 significantly reduced the proliferation rate of A549 cells and increased the percentage of apoptotic A549 cells (p<0.05). Similarly, it was found in colony formation assay that the overexpression of miR-188 inhibited the colony formation ability of A549 cells most significantly (p<0.05). SIX1 was a direct target for miR-188, and its mRNA and protein expressions were downregulated by the overexpression of miR-188. The remarkable downregulation of phosphorylated ERK was observed in A549 cells overexpressing miR-188, while the decline in phosphorylated ERK was reversed in A549 cells overexpressing miR-188 and SIX1.
The expression of miR-188 is downregulated in LUAD cell lines. The overexpression of miR-188 inhibits proliferation and promotes apoptosis of LUAD cells, whose functional mechanism may be related to its regulation on the ERK signaling pathway by targeting SIX1.
High strain-rate rolling (HSRR) was successfully used to produce Mg–6.0 Zn–0.5 Zr sheets at 250–400°C. All the sheets have ultrafine-grained structures and exhibit excellent strength and ductility. ...Extensive deformation twinning, production of high-density dislocations in twins, subsequent continuous dynamic recrystallization (DRX) and discontinuous DRX contribute to the feasibility of HSRR and to the ultrafine-grained structures. The excellent mechanical properties are ascribed to the ultrafine grains, low dislocation density and weakened basal texture in the final structure.
ABSTRACT
The follow-up timing observations were carried out for 24 pulsars discovered with the Five-hundred-meter Aperture Spherical radio Telescope (FAST) in Commensal Radio Astronomy FAST Survey. ...We report their phase-connected timing ephemeris, polarization pulse profiles, and Faraday rotation measurements. With their spin periods spanning from 2.995 ms to 4.34 s, their period derivatives were determined to spread between 7.996(8) × 10−21 and 9.83(3) × 10−15 s s−1, which imply that they have characteristic ages from 1.97 × 106 to 5.93 × 109 yr. It is inferred that PSRs J0211+4235 and J0518+2431 are beyond the ‘traditional death line’. PSR J0211+4235 is beyond the ‘death valley’. The death line model of Zhang et al. also cannot explain the radio presence of PSR J0211+4235. This suggests that radiation theory needs to be improved. Besides, ten of the 22 canonical pulsars show nulling phenomena. Moreover, PSR J1617+1123 exhibits variation of emission and J0540+4542 shows subpulse drifting. The DM of five pulsars is larger than the estimated by the YMW16 electron density model, which could suggest that electron density models need updates for higher Galactic latitude regions. PSRs J0447+2447 and J1928−0548 are isolated millisecond pulsars. With their flux densities spanning from 5(1)–553(106) μJy, some of these new pulsars found by FAST are distant, dim, and low-$\dot{E}$ ones and are suitable for testing pulsar emission theories.
The study investigated the effects of dietary curcumin supplementation on tissue distribution of curcumin and its metabolites, intestinal antioxidant capacity, and expression of ...detoxification-related genes in ducks. A total of 720 one-day-old male Cherry Valley Pekin ducklings (initial BW 58.6 ± 0.1 g) were randomly assigned to 4 dietary groups each with 6 replicates of 30 ducks using a single factorial arrangement design. Ducks in the control group were fed a basal diet and the remainder were fed the basal diet supplemented with 200, 400, or 800 mg/kg curcumin. The experiment lasted for 21 D. Curcumin was present at 13.12 to 16.18 mg/g in the cecal digesta, 75.50 to 575.40 μg/g in jejunal mucosa, 35.10 to 73.65 μg/g in liver, and 7.02 to 7.88 μg/mL in plasma. The jejunal and hepatic contents of curcumin increased significantly (P < 0.05) in response to supplementation with 400 and 800 mg/kg of curcumin respectively, compared with 200 mg curcumin/kg group. There was a linear (P < 0.001) effect of dietary curcumin on relative abundance of SOD1, GPX1, CAT, HO-1, and Nrf2 transcripts, and a quadratic (P < 0.001) increase in the activities of GSH-Px and T-AOC in jejunal mucosa. The expression of CYP1A4, CYP2D17 increased and CYP1B1, CYP2A6 decreased linearly (P < 0.001) with dietary curcumin concentrations. In addition, dietary curcumin increased gene expression of GST, MRP6, and ABCB1 in jejunal mucosa. In conclusion, dietary supplementation with 200 to 800 mg/kg curcumin enhanced the accumulation of curcumin and its metabolites in jejunum as well as increasing the antioxidant capacity and detoxification potential, which play major roles in the protection of duck intestines against damage.
Solar wind parameters play a dominant role in reconnection rate, which controls the solar wind‐magnetosphere coupling efficiency at Earth's magnetopause. Besides, low‐energy ions from the ionosphere, ...frequently detected on the magnetospheric side of the magnetopause, also affect magnetic reconnection. However, the specific role of low‐energy ions in reconnection is still an open question under active discussion. In the present work, we report in situ observations of a multiscale, multi‐type magnetopause reconnection in the presence of low‐energy ions using NASA's Magnetospheric Multiscale data on September 11, 2015. This study divides ions into cold (10–500 eV) and hot (500–30,000 eV) populations. The observations can be interpreted as a secondary reconnection dominated by electrons and cold ions (mainly in XYGSE plane) located at the edge of an ion‐scale reconnection (mainly in XZGSE plane). This analysis demonstrates a dominant role of cold ions in the secondary reconnection without hot ions' response. Cold ions and electrons are accelerated and heated by the secondary process. The case study provides observational evidence for the simultaneous operation of antiparallel and component reconnection. Our results imply that the pre‐accelerated and heated cold ions and electrons in the secondary reconnection may participate in the primary ion‐scale reconnection affecting the solar wind‐magnetopause coupling and the complicated magnetic field topology could affect the reconnection rate.
Key Points
We report Magnetospheric Multiscale observations of a multiscale, multi‐type magnetopause reconnection in the presence of low‐energy ions
An electron‐cold ion reconnection, dominated by low‐energy ions and electrons, is located at the edge of an ion‐scale reconnection
The multiscale reconnection provides observational evidence for the simultaneous operation of antiparallel and component reconnection
Abstract
The protective performance of a composite structure composed of the composite layer (FC composite) as the matrix armor and the ballistic ceramic layer as the faceplate against Type 53 7.62 ...mm Armor-Piercing Incendiary (API) is studied. FC composite is used as the hybrid fiber layer mainly containing carbon fiber, and the ballistic ceramic layer is respectively made of three kinds of ballistic ceramics: alumina, silicon carbide and boron carbide. The results show that the weight of boron carbide ceramic is 14% ~ 30% less than that of alumina ceramic and 10% ~ 24% less than that of silicon carbide ceramic under equal thickness of the FC composite substrate. The lowest total areal density is 44 kg/m
2
when the bearing capacity of the armored vehicle is basically satisfied.
Early diagnosis of patients with dilated cardiomyopathy (DCM) remains challenging. Cardiac MR can correlate myocardial changes with their pathological basis. There have been some previous studies on ...the effect of T1 mapping in DCM, but there is limited data on the incremental value of T2 mapping for DCM in routine clinical practice. This study will examine whether the combination of MRI T1 and T2 mapping offers greater advantages in the diagnosis of DCM.
The study included 28 patients with DCM and 21 healthy controls. CMR evaluation included late gadolinium enhancement (LGE), T1 mapping, extracellular volume (ECV) fraction and T2 mapping. The DCM group was divided into LGE (+) and LGE (−) subgroups. The main modes of LGE are subendocardial, midwall, subepicardial, or transmural. T1 values, T2 values, and ECV in the 16 segments myocardial levels were measured by post-processing software. Student's t-tests or Mann–Whitney U test was used to compare between two groups, and one-way ANOVA or Kruskal–Wallis H test was used to compare between multiple groups, with p values corrected by Bonferroni. The difference was considered statistically significant at P < 0.05. ROC curve analysis was used to compare the area under the curve (AUC) of each index and its combined value, and the cut-off value, sensitivity and specificity were determined by Jordan's index.
Mean native myocardial T1, ECV and T2 were significantly higher in the DCM group compared to controls (p ≤ 0.001, respectively). The best cut-off values for T1, T2 and ECV to discriminate DCM from controls were 1184 ms, 40.9 ms and 29.2%, respectively. The AUC of T1, ECV and T2 were 0.87, 0.89, and 0.83, respectively. The combined AUC of the three values was 0.96.
Native T1 value and ECV overcome some of the limitations of LGE, and the T2 helps to understand the extent of myocardial damage. The combination of T1 and T2 mapping techniques can reveal fibrotic and oedematous changes in the early stages of DCM, providing a more comprehensive assessment of DCM and better guidance for individualised clinical management of patients.
We suggest that the addition of T2 mapping to the routine CMR examination of patients with suspected DCM, and the combined assessment of T1mapping and T2 mapping can provide complementary information about the disease and improve the early diagnosis of DCM.
Abstract
This research was carried out with focus on the multi-scale structure of meretrix lusoria shell. In mesoscopic, meretrix lusoria shell contains three layers; the thickness of different ...layers is 0.6mm, 0.8mm and 0.7mm respectively. Compared to mesoscopic structure, the microstructure also has three layers, it refers to cuticle, prismatic layer and nacre. The cuticle is composed of a great number of particles, and its main composition is protein.The prismatic layer is composed of stagger structure. The inner layer presents orthogonal-sheets arrangement. This microstructure might show a special enhanced effect for the whole shell. The different inorganic layers’ crystal is same, which is aragonite. The mechanical properties of Meretrix lusoria shell are excellent, its elastic modulus was the same order of magnitude of high strength glass fiber composites. From this research will provide the theoretical basis for designing and producing bioinspired composite materials.
Abstract
In this study, Polybenzoxazole (PBO) nanofiber membranes are prepared by applying a three-step process, including synthesis of the electrospinning precursor with ortho-hydroxyl, ...electrospinning, and thermal conversion. Electrospinning is conducted at 10 kV with a distance of 10 cm and the solution concentration is 17.8% (w/v). Different flow rates are adopted to prepare polymer nanofiber membranes and test their properties. At the rate of 0.5 μL/min and 1 μL/min, uniform and compact films with nanofibers are obtained. The high-temperature transition from the precursor to PBO is then investigated systematically. Thermal treatment at 420°C is needed for complete cyclodecarboxylation conversion from the precursor to PBO. Diameters of the fibers in the as-prepared PBO nanofiber membrane are within the range of 120-130 nm. The membrane shows high thermal stability with the decomposition temperature of 619.8°C in N
2
and 513.6°C in air respectively, presenting a promising application prospect in high-temperature areas.
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