68 research outputs found
Radio-sensitizing effect of ethyl caffeate on nasopharyngeal carcinoma CNE-2 cell line
Purpose: To investigate the radio-sensitizing effect of ethyl caffeate (ETF) on naso-pharyngeal carcinoma.Methods: MTT (3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide) assay was used to evaluate the cell viability of CNE-2 cells, while their levels of caspase-3 and caspase-9 were determined by enzyme-linked immunosorbent assay (ELISA). In addition, a xenograft model was established in nude mice. The model was treated with ETF (40 mg/kg) and subjected to β-irradiation (10 Gy) for 28 days, during which tumor volume was determined at 4-day intervals. Expressions of caspase-3, caspase-9 and Bcl-2 were determined by western blotting assay.Results: β-irradiation (10 Gy) did not produce any obvious inhibitory effect on the proliferation of CNE-2 cells. However, ETF (10, 20 and 40 μg/mL) significantly enhanced the radiosensitivity of the cells to β- irradiation (p < 0.01) and significantly increased their levels of caspase-3 and caspase-9 (p < 0.01). The combination of ETF (40 mg/kg) with β-irradiation resulted in significant inhibition of tumor growth in mice xenograft model (p < 0.01). The combined treatment also resulted in significant up-regulation of expressions of caspase-3 and casepase-9 and significant down-regulation of Bcl-2 in the tumor tissues when compared with corresponding tissues from the control mice (p < 0.01).Conclusion: ETF significantly enhances the sensitivity of naso-pharyngeal carcinoma CNE-2 cells to β- irradiation, probably through induction of mitochondria-mediated apoptosis. ETF may be useful for treating naso-pharyngeal carcinoma in combination with radiation therapy.Keywords: Ethyl caffeate, Radio-sensitizing effects, Caspase, Nasopharyngeal carcinoma, CNE-2 cell line, β-irradiatio
Broad-Wavevector Spin Pumping of Flat-Band Magnons
We report the experimental observation of large spin pumping signals in
YIG/Pt system driven by broad-wavevector spin-wave spin current. 280 nm-wide
microwave inductive antennas offer broad-wavevector excitation which, in
combination with quasi-flatband of YIG, allows a large number of magnons to
participate in spin pumping at a given frequency. Through comparison with
ferromagnetic resonance spin pumping, we attribute the enhancement of the spin
current to the multichromatic magnons. The high efficiency of spin current
generation enables us to uncover nontrivial propagating properties in ultra-low
power regions. Additionally, our study achieves the spatially separated
detection of magnons, allowing the direct extraction of the decay length. The
synergistic combination of the capability of broad-wavevector excitation,
enhanced voltage signals, and nonlocal detection provides a new avenue for the
electrical exploration of spin waves dynamics
Clinical and Biological Implications of Mutational Spectrum in Acute Myeloid Leukemia of FAB Subtypes M0 and M1
Background/Aims: Acute myeloid leukemia (AML) of French-American-British (FAB) subtypes M0 and M1 are both poorly differentiated AML, but their mutational spectrum and molecular characteristics remain unknown. This study aimed to explore the mutational spectrum and prognostic factors of AML-M0 and M1. Methods: Sixty-five AML patients derived from The Cancer Genome Atlas (TCGA) database were enrolled in this study. Whole-genome sequencing was performed to depict the mutational spectrum of each patient. Clinical characteristics at diagnosis, including peripheral blood (PB) white blood cell counts (WBC), blast percentages in PB and bone marrow (BM), FAB subtypes and the frequencies of known recurrent genetic mutations were described. Survival was estimated using the Kaplan-Meier methods and log-rank test. Univariate and multivariate Cox proportional hazard models were constructed procedure. Results: Forty-six patients had more than five recurrent genetic mutations. FLT3 had the highest mutation frequency (n=20, 31%), followed by NPM1 (n=18, 28%), DNMT3A (n=16, 25%), IDH1 (n=14, 22%), IDH2 (n=12, 18%), RUNX1 (n=11, 17%) and TET2 (n=7, 11%). Univariate analysis showed that age >= 60 years and TP53 mutations had adverse effect on EFS (P=0.015, P=0.036, respectively) and OS (P=0.003, P=0.004, respectively), WBC count >= 50x10(9)/L and FLT3-ITD negatively affected EFS (P=0.003, P=0.034, respectively), whereas NPM1 mutations had favorable effect on OS (P=0.035) and allogeneic hematopoietic stem cell transplantation (allo-HSCT) on EFS and OS (all P= 50x10(9)/L was an independent risk factor for EFS (P=0.002) and TP53 mutations for OS (P=0.043). Conclusions: Our study provided new insights into the mutational spectrum and molecular signatures of AML-M0 and M1. We proposed that FLT3-ITD, NPM1 and TP53 be identified as markers for risk stratification of AML-M0 and M1. Patients with AML-M0 and M1 would likely benefit from allo-HSCT. (C) 2018 The Author(s) Published by S. Karger AG, Base
Observation of Fluctuation Spin Hall Effect in Antiferromagnet
The spin Hall effect (SHE) can generate a pure spin current by an electric
current, which is promisingly used to electrically control magnetization. To
reduce power consumption of this control, a giant spin Hall angle (SHA) in the
SHE is desired in low-resistivity systems for practical applications. Here,
critical spin fluctuation near the antiferromagnetic (AFM) phase-transition is
proved as an effective mechanism to create an additional part of SHE, named as
fluctuation spin Hall effect (FSHE). This FSHE enhances the SHA due to the AFM
spin fluctuation between conduction electrons and local spins. We detect the
FSHE with the inverse and direct spin Hall effect (ISHE and DSHE) set-up and
their temperature (T) dependences in the Cr/MgO/Fe magnetic tunnel junctions
(MTJs). The SHA is significantly enhanced when temperature is approached to the
N\'eel temperature (T_N) and has a peak value of -0.34 at 200 K near T_N. This
value is higher than the room-temperature value by 240% and comparable to that
of heavy metals Ta and W. Furthermore, the spin Hall resistivity of Cr well
fits the modeled T-dependence when T approaches T_N from low temperatures,
implying the AFM spin fluctuation nature of strong SHA enhancement. Thus, this
study demonstrates the critical spin fluctuation as a prospective way of
increasing SHA and enriches the AFM material candidates for spin-orbitronic
devices.Comment: 27 pages, 9 figure
Genetic analysis of 23 Y-STR loci in the Va population from Yunnan Province, Southwest China
Background Y-chromosomal short tandem repeat (Y-STR) polymorphisms are widely used in forensic DNA analysis. However, there is a lack of information about the Chinese Va population in the Y-STR Haplotype Reference Database. Aim To establish the Y-chromosome Haplotype Reference Database of the Yunnan Va population and investigate the population genetic relationships with other geographically adjacent groups. Subjects and methods In total, 23 Y-STR loci were genotyped with the PowerPlex Y23 Kit in 368 unrelated healthy Va males from Yunnan Province, Southwest China. Genetic polymorphism was analysed using the YHRD’s AMOVA tools and the MEGA 6.0 software. Results The gene diversity (GD) of the 23 Y-STR loci ranged from 0.3092 (DYS19) to 0.7868 (DYS385a/b). According to haplotype analysis, 204 different haplotypes were obtained, out of which 144 were unique. The haplotype diversity (HD) and discrimination capacity (DC) were 0.9852 and 0.5543, respectively. By comparing the Yunnan Va group with the other 22 referential groups, the results revealed that Yunnan Va was isolated from other groups. Conclusions The 23 Y-STR loci were highly polymorphic and informative in the Yunnan Va population, and the results enriched the basic genetic information for forensic investigation and population genetic studies
Roles of ethylene glycol solvent and polymers in preparing uniformly distributed MgO nanoparticles
This study focus on specifying the roles of solvent ethylene glycol (EG) and polymers for synthesis of uniformly distributed magnesium oxide (MgO) nanoparticles with average crystallite size of around 50 nm through a modified polyol method. Based on different characterization results, it was concluded that, Mg2+ ions was precipitated by the −OH and CO32− ions decomposed from urea in ethylene glycol (EG) medium (CO(NH2)2 → NH3 + HNCO, HNCO + H2O → NH3 + CO2), thus forming well crystallized Mg5(CO3)4(OH)2 (H2O)4 precursor which could be converted to MgO by calcination. Surface protectors PEG and PVP have no obvious influences on cyrtsal structure, morphology and size uniformity of as-prepared precursors and target MgO nanoparticles. In comparison with polymers PEG and PVP, solvent EG plays an important role in controlling the morphology and diameter uniformity of MgO nanoparticles
Temporal collaborative attention for wind power forecasting
Wind power serves as a clean and sustainable form of energy. However, its generation is fraught with variability and uncertainty, owing to the stochastic and dynamic characteristics of wind. Accurate forecasting of wind power is indispensable for the efficient planning, operation, and grid integration of wind energy systems. In this paper, we introduce a novel forecasting method termed Temporal Collaborative Attention (TCOAT). This data-driven approach is designed to capture both temporal and spatial dependencies in wind power generation data, as well as discern long-term and short-term patterns. Utilizing attention mechanisms, TCOAT dynamically adjusts the weights of each input variable and time step based on their contextual relevance for forecasting. Furthermore, the method employs collaborative attention units to assimilate directional and global information from the input data. It also explicitly models the interactions and correlations among different variables or time steps through the use of self-attention and cross-attention mechanisms. To integrate long-term and short-term information effectively, TCOAT incorporates a temporal fusion layer that employs concatenation and mapping operations, along with hierarchical feature extraction and aggregation. We validate the efficacy of TCOAT through extensive experiments on a real-world wind power generation dataset from Greece and compare its performance against twenty-two state-of-the-art methods. Experimental results demonstrate that TCOAT outperforms existing methods in terms of both accuracy and robustness in wind power forecasting. Moreover, we conduct a generality study on an additional real-world dataset from a different climate condition and wind power characteristics. The results show that TCOAT can achieve comparable or better performance than the state-of-the-art methods, confirming the generalization ability of TCOAT
Comparison of Mean Dynamic Topography Modeling from Multivariate Objective Analysis and Rigorous Least Squares Method
Filtering methods are usually used to combine the mean sea surface (MSS) and geoid (computable by global geopotential model (GGM)) into a common subspace, to model mean dynamic topography (MDT), which may lead to signal leakage and distortion problems. The use of the rigorous least squares (LS) method and multivariate objective analysis (MOA) alleviates these problems, and the derived MDTs from these two methods show better performance than MDTs derived from filtering methods. However, the advantages and disadvantages of these two methods have not been evaluated, and no direct comparison has yet been conducted between these two approaches regarding the performances in MDT recovery. In this study, we compare the performances of the MOA method with the LS method, providing information with respect to the usability of different methods in MDT modeling over regions with heterogeneous ocean states and hydrological conditions. We combined a recently published mean sea surface called DTU21MSS, and a satellite-only GGM named GO_CONS_GCF_2_DIR_R6, for MDT computation over four typical study areas. The results showed that the MDTs derived from the LS method outperformed the MOA method, especially over coastal regions and ocean current areas. The root mean square (RMS) of the discrepancies between the LS-derived MDT and the ocean reanalysis data was lower than the RMS of the discrepancies computed from the MOA method, by a magnitude of 1–2 cm. The formal error of the MDT estimated by the LS method was more reasonable than that derived from the MOA method. Moreover, the geostrophic velocities calculated by the LS-derived MDT were more consistent with buoy data than those calculated by the MOA-derived solution, by a magnitude of approximately 1 cm/s. The reason can be attributed to the fact that the LS method forms the design matrix segmentally, based on the error characteristics of the GGM, and suppresses high-frequency noise by applying constraints in different frequency bands, which improves the quality of the computed MDT. Our studies highlight the superiority of the LS-derived method versus the MOA method in MDT modeling
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