56 research outputs found
Epigenetic hypomethylation and upregulation of GD3s in triple negative breast cancer.
Background: Breast cancer remains a major health problem in the world. Triple-negative breast cancer (TNBC) is an aggressive subtype with very poor prognosis. Up to now, the mechanism behind TNBC\u27s activity is still unclear and no candidate drug target has been identified. Thus, it is of critical importance to elucidate the pathways in TNBC and identify the relevant biomarkers. Recent studies showed that ganglioside D3 synthase (GD3s) played a very important role in development of cancers. However, the physiological functions and associated pathways of GD3s in TNBC are still unclear.
Methods:
Results:
Conclusions: In summary, these results suggest that GD3s may be a potential biomarker and drug target in treatment of TNBC
miR-29c plays a suppressive role in breast cancer by targeting the TIMP3/STAT1/FOXO1 pathway.
Background: miR-29c has been associated with the progression of many cancers. However, the function and mechanism of miR-29c have not been well investigated in breast cancers.
Methods: Real-time quantitative PCR was used to assess expression of miR-29c and DNMT3B mRNA. Western blot and immunochemistry were used to examine the expression of DNA methyltransferase 3B (DNMT3B) protein in breast cancer cells and tissues. The functional roles of miR-29c in breast cancer cells such as proliferation, migration, invasion, colony formation, and 3D growth were evaluated using MTT, transwell chambers, soft agar, and 3D Matrigel culture, respectively. In addition, the luciferase reporter assay was used to check if miR-29c binds the 3\u27UTR of DNMT3B. The effects of miR-29c on the DNMT3B/TIMP3/STAT1/FOXO1 pathway were also examined using Western blot and methyl-specific qPCR. The specific inhibitor of STAT1, fludarabine, was used to further check the mechanism of miR-29c function in breast cancer cells. Studies on cell functions were carried out in DNMT3B siRNA cell lines.
Results: The expression of miR-29c was decreased with the progression of breast cancers and was closely associated with an overall survival rate of patients. Overexpression of miR-29c inhibited the proliferation, migration, invasion, colony formation, and growth in 3D Matrigel while knockdown of miR-29c promoted these processes in breast cancer cells. In addition, miR-29c was found to bind 3\u27UTR of DNMT3B and inhibits the expression of DNMT3B, which was elevated in breast cancers. Moreover, the protein level of TIMP3 was reduced whereas methylation of TIMP3 was increased in miR-29c knockdown cells compared to control. On the contrary, the protein level of TIMP3 was increased whereas methylation of TIMP3 was reduced in miR-29c-overexpressing cells compared to control. Knockdown of DNMT3B reduced the proliferation, migration, and invasion of breast cancer cell lines. Finally, our results showed that miR-29c exerted its function in breast cancers by regulating the TIMP3/STAT1/FOXO1 pathway.
Conclusion: The results suggest that miR-29c plays a significant role in suppressing the progression of breast cancers and that miR-29c may be used as a biomarker of breast cancers
Probing NaCl hydrate formation from aqueous solutions by Terahertz Time-Domain Spectroscopy
The cooling-induced formation of hydrate in aqueous NaCl solutions was probed using terahertz time-domain spectroscopy (THz-TDS). It was found that the NaCl hydrate formation is accompanied with emergence of four new absorption peaks at 1.60, 2.43, 3.34 and 3.78 THz. Combining the X-ray diffraction measurement with the solid-state based density functional theory (DFT) calculations, we assign the observed terahertz absorption peaks to the vibrational modes of the formed NaClâ‹…2H2O hydrate during cooling. This work dedicates THz-TDS based analysis great potential in studying ionic hydrate and the newly revealed collective vibrational modes could be the sensitive indicators to achieve quantitative analysis in phase transitions and lattice dynamics
Best Subset Selection with Efficient Primal-Dual Algorithm
Best subset selection is considered the `gold standard' for many sparse
learning problems. A variety of optimization techniques have been proposed to
attack this non-convex and NP-hard problem. In this paper, we investigate the
dual forms of a family of -regularized problems. An efficient
primal-dual method has been developed based on the primal and dual problem
structures. By leveraging the dual range estimation along with the incremental
strategy, our algorithm potentially reduces redundant computation and improves
the solutions of best subset selection. Theoretical analysis and experiments on
synthetic and real-world datasets validate the efficiency and statistical
properties of the proposed solutions.Comment: arXiv admin note: text overlap with arXiv:1703.00119 by other author
Advance of Lung Cancer Screening with Low-dose Spiral CT
Lung cancer has become the leading cause of cancer mortality globally, and 5-year survival rate is very poor. Screening and early detection are vital to improve survival and decrease mortality of lung cancer. In recent 20 years, low-dose spiral CT (LDCT) screening has become a research focus in this area. Randomized controlled trials have confirmed that LDCT can decrease lung cancer mortality. However, there are still some problems of LDCT. In this paper, we summarized the controversy that whether low-dose helical CT screening can reduce lung cancer mortality or not before its effectiveness was been confirmed, the results and problems in the randomized controlled trials and gave a prospect of low-dose helical CT screening’s future application
Weakened Interfacial Hydrogen Bond Connectivity Drives Selective Photocatalytic Water Oxidation toward H<sub>2</sub>O<sub>2</sub> at Water/Brookite-TiO<sub>2</sub> Interface
The
formation of H2O2 through the two-electron
photocatalytic water oxidation reaction (WOR) is significant but encounters
the competition with the four-electron O2 evolution reaction.
Recent studies showed a crystal-phase dependence in H2O2 selectivity, where high purity brookite TiO2 (b-TiO2) exhibits remarkable H2O2 selectivity
in contrast to the common rutile phase TiO2 (r-TiO2). However, the origin of such a structure-induced selectivity
preference remains elusive, primarily due to the complexities associated
with the solid–liquid interface system and excited-state chemistry.
Herein, we conducted a comprehensive investigation into the selectivity
mechanism of WOR at the water/b-TiO2(210) and water/r-TiO2(110) interfaces, employing first-principles molecular dynamics
simulations and microkinetic analyses. Intriguingly, our results reveal
that the intrinsic catalytic ability of the b-TiO2(210)
itself does not enhance H2O2 selectivity compared
to r-TiO2(110). Instead, it is the weakened interfacial
hydrogen bond connectivity, modulated by the herringbone-like local
atomic structure of the b-TiO2(210) surface, that determines
the selectivity. Specifically, this weakened H-bond connectivity (i.e.,
local low water density) at the interface, owing to the strong water
adsorption and distinct adsorption orientation, can stabilize the
OH• radical and inhibit its deprotonation, leading
to an improved H2O2 selectivity. By contrast,
the relatively strong interface H-bond connectivity established over
r-TiO2(110) accelerates the deprotonation of OH•, with the OH• coverage being 3 orders of magnitude
lower than at the water/b-TiO2(210) interface. This study
quantitatively demonstrates that the local H-bond structure (water
density) at the liquid/solid interface significantly influences photocatalytic
selectivity, and this insight may offer a rational approach to enhance
the H2O2 selectivity
Improving soil hydrological simulation under freeze–thaw conditions by considering soil deformation and its impact on soil hydrothermal properties
Traditional agricultural or eco-hydrological models usually ignore soil deformation and its impact on hydrothermal properties when simulating soil water, heat, and salt transport under freeze–thaw conditions. As a result, significant errors may occur when these models are used in areas with considerable frost heave, such as arid areas with shallow groundwater tables. In this study, the simultaneous heat and water model (SHAW model) was modified with considering soil deformation and its impact on hydrothermal properties during the freeze–thaw period. The modified SHAW model was then validated using the experimental data collected at the Hetao Irrigation District, in the upper Yellow River basin. Comparison between the simulated and observed data showed that the modified SHAW model performed well and obviously better than the original SHAW model in simulating the soil water, heat, and salt transport. As compared with the SHAW model, the modified SHAW model averagely decreased the RMSE value by 37.5% and 23% for soil water content and soil temperature, respectively. The modified model can be used as a decision tool for water management and salinity control of farmland in cold areas with significant frost heave
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