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ERK phosphorylation functions in invadopodia formation in tongue cancer cells in a novel silicate fibre-based 3D cell culture system 被引量:2
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作者 Masaharu Noi Ken-Ichi Mukaisho +8 位作者 Saori Yoshida Shoko Murakami Shinya Koshinuma Takeshi Adachi Yoshisato Machida Masashi Yamori Takahisa Nakayama Gaku Yamamoto Hiroyuki Sugihara 《International Journal of Oral Science》 SCIE CAS CSCD 2018年第4期253-262,共10页
To screen for additional treatment targets against tongue cancer, we evaluated the contributions of extracellular signal-related kinase(ERK), AKT and ezrin in cancer development. Immunohistochemical staining showed th... To screen for additional treatment targets against tongue cancer, we evaluated the contributions of extracellular signal-related kinase(ERK), AKT and ezrin in cancer development. Immunohistochemical staining showed that ERK and ezrin expressions were significantly higher in invasive squamous cell carcinoma than in carcinoma in situ. To investigate the roles of ERK and ezrin in cancer development, we used the non-woven silica fibre sheet Cellbedwith a structure resembling the loose connective tissue morphology in a novel 3 D culture system. We confirmed that the 3 D system using CellbedTMaccurately mimicked cancer cell morphology in vivo. Furthermore, cell projections were much more apparent in 3 D-cultured tongue cancer cell lines than in 2 D cultures. Typically, under conventional 2 D culture conditions, F-actin and cortactin are colocalized in the form of puncta within cells.However, in the 3 D-cultured cells, colocalization was mainly observed at the cell margins, including the projections. Projections containing F-actin and cortactin colocalization were predicted to be invadopodia. Although suppressing ezrin expression with small interfering RNA transfection caused no marked changes in morphology, cell projection formation was decreased, and the tumour thickness in vertical sections after 3 D culture was markedly decreased after suppressing ERK activity because both the invasion ability and proliferation were inhibited. An association between cortactin activation as well as ERK activity and invadopodia formation was detected. Our novel 3 D culture systems using Cellbed? are simple and useful for in vitro studies before conducting animal experiments. ERK contributes to tongue cancer development by increasing both cancer cell proliferation and migration via cortactin activation. 展开更多
关键词 ERK phosphorylation functions in invadopodia formation in tongue cancer cells in a novel silicate fibre-based 3D cell culture sy HSC
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Curvature and Size Effects on Reactivities of Mono-to Octa-vacancies in a(5,5) Single-walled Carbon Nanotube 被引量:1
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作者 贾桂霄 李磊 +3 位作者 王晓霞 孙松松 包金小 安胜利 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第4期621-630,共10页
Defect curvature was developed based on our previously proposed direction curvature theory. Defect curvature, as a universal criterion, was used to identify vacancy formation energies E_f of mono-vacancies to octa-vac... Defect curvature was developed based on our previously proposed direction curvature theory. Defect curvature, as a universal criterion, was used to identify vacancy formation energies E_f of mono-vacancies to octa-vacancies in a(5,5) tube. An ab initio calculation results showed that E_f decreased with increasing the defect curvature K_(V_s)(s = 1~8). The structures with removed carbon atoms along zigzag chain or the tubular axis were the most stable in each kind of Vs, because their corresponding K_(V_s) was the largest. In addition, local product structures disturbed the variation rule of E_f as K_(V_s). There was an odd-even oscillation rule in the smallest E_f among each kind of Vs as the s value and vacancies V2, V4 and V6 were more stable. The stabilities of the related vacancy structures were confirmed by two dissociation processes. 展开更多
关键词 defect curvature atomic vacancies vacancy formation energies density functional theory
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Quantum of Space of the Universe—Correction of Previous Mistakes
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作者 Valentyn Nastasenko 《Journal of Applied Mathematics and Physics》 2021年第4期565-576,共12页
A large number of scientific works, from ancient times to the present, have been dedicated to the search for “bricks” that make up the foundations of the material world. Justification of quantum of space parameters ... A large number of scientific works, from ancient times to the present, have been dedicated to the search for “bricks” that make up the foundations of the material world. Justification of quantum of space parameters of the Universe is a complicated scientific problem, as its reliable information is unknown. Therefore, errors may appear in it, which must be corrected in a timely manner. In the latest works from this sphere, the quanta of the space of the Universe are replaced by hexahedral prisms instead of balls, which solves the problem of their dense packing. However, the mistake was the deformation of these prisms. <strong>The purpose of this work</strong> is to eliminate this deficiency. Its scientific novelty is the substantiation of the specified of refined parameters of the quantum of the space of the Universe on the basis of strict scientific provisions and the physical laws of nature. The solution to this problem is an urgent and important scientific and applied task, since it develops knowledge about the quantum foundations of the material world and the Universe as a whole. <strong>Research methods which used in this work:</strong> The performed work is based on the methods of deduction and induction in the research of the material world based on the application of the well-known reliable laws of physics and the general principles of the development of the theory of knowledge. Other research methods are still unknown, since the work performed is associated with new scientific discoveries, the search for which is difficult to formalize by known technique methods. <strong>Results and their discussion:</strong> The work is based on the hypothesis that was put forward that at the quantum-mechanical level of the material world, a longitudinal quantum shift by the wavelength <em>λ<sub>G</sub></em> and a transverse quantum shift by <em>λ<sub>G</sub></em> of the quantum of the Universe space is carried out in the time interval <em>T<sub>G</sub></em>, which can be found on the basis of the Heisenberg uncertainty principle. The parameters obtained made it possible to clarify the length and shape of quanta of the space of the Universe, as well as the conditions for its rotation. It was also taken into account that the hexagonal prism of the circular quantum of the space of the Universe is composed of 6 trihedral prisms of elementary quanta of space. So she can be formed by 3 elements of real quark with a common top in the center of the prism, with the formation of 3 elements of virtual quark between them. In this case, a transverse shift by <em>λ<sub>G</sub></em> and a rotation of quarks by an angle of 2π/6 radians is performed without energy loss, only due to transformations of their real and virtual states. The totality of all the above transformations of quanta of the space of the Universe does not contradict previously known physical laws and regularities, which serves as the basis for confirming the scientific hypothesis put forward. 展开更多
关键词 Quantum of Space of the Universe Subject to Its Formation and functioning
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Comparative DFT Study of [Mg(CHZ)_3](ClO_4)_2 and [Mg(CHZ)_3](NO_3)_2(CHZ=Carbohydrazide)
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作者 聂西度 黄辉胜 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第4期679-683,共5页
The molecular geometry,electronic structure,thermochemistry and infrared spectra of [Mg(CHZ)3](ClO4)2 and [Mg(CHZ)3](NO3)2 were comparatively studied using the Heyd-Scuseria-Ernzerhof(HSE) screened hybrid de... The molecular geometry,electronic structure,thermochemistry and infrared spectra of [Mg(CHZ)3](ClO4)2 and [Mg(CHZ)3](NO3)2 were comparatively studied using the Heyd-Scuseria-Ernzerhof(HSE) screened hybrid density functional with 6-31G** basis set.The experimental results show that the complexes have six-coordinated octahedron feature,and the metal-ligand interactions are predominantly ionic in nature.The calculated heats of formation predict that [Mg(CHZ)3](NO3)2 is more stable than [Mg(CHZ)3](ClO4)2.Detailed NBO analyses indicate that the ligand-anion interaction plays an important role in the stability for these two energetic complexes.Moreover,the stretching vibration frequencies of N-H bonds shift to lower wave number compared to the free CHZ ligand,which are caused by the delocalizations from N-H bond orbital to lone-pair electron antibond orbital of magnesium. 展开更多
关键词 energetic complex carbohydrazide density functional theory electronic structure heats of formation
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Density functional theory study on the influence of cation ratio on the host layer structure of Zn/Al double hydroxides 被引量:1
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作者 Hong Yan Min Wei +1 位作者 Jing Ma Xue Duan 《Particuology》 SCIE EI CAS CSCD 2010年第3期212-220,共9页
A density functional theory (DFT) study has been carried out for [Zn-1AI(OH2)n+6(OH)2n-2]^3+ (n=3-6) and [Znn-1AI(OH2)2n-2(OH)2n-2]^3+ (n = 7) clusters, which include the basic structural information ... A density functional theory (DFT) study has been carried out for [Zn-1AI(OH2)n+6(OH)2n-2]^3+ (n=3-6) and [Znn-1AI(OH2)2n-2(OH)2n-2]^3+ (n = 7) clusters, which include the basic structural information of the brucite-like lattice structure of Zn/Al layered double hydroxides (LDHs) with Zn/AI molar ratio (R) in the range 2-6, in order to understand the effect of the Zn/Al ratio on the structure and stability of binary Zn/Al LDHs. Based on systematic calculations of the geometric parameters and formation energies of the cluster models, it was found that it is possible for Zn^2+ and Al^3+ cations to replace Mg^2+ isomorphously in the brucite-like structure with different R values, resulting in differences in microstructure of the clusters and unit cell parameter a of the Zn/Al LDHs. Analysis of the geometry and bonding around the trivalent Al^3+ or divalent Zn^2+ cations reveals that Al^3+ plays a more significant role than Zn^2+ in determining the microstructure properties, formation and bonding stability of the corresponding ZnRAl clusters when R〈5, while the influence of Zn^2+ becomes the dominant factor in the case of R〉 5. These findings are in good agreement with experiments. This work provides a detailed electronic-level understanding of how the composition of cations affects the microstructure and stability of Zn-containing binary LDH layers. 展开更多
关键词 Layered double hydroxide Zn/Al molar ratio Density functional calculation Microstructure Formation and bonding stability
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Functional diversifications of Gh ERF1 duplicate genes after the formation of allotetraploid cotton 被引量:2
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作者 Chunxiao Liu Tian Zhen Zhang 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2019年第1期60-74,共15页
Whole genome duplication, a prevalent force of evolution in plants, results in massive genome restructuring in different organisms. Roles of the resultant duplicated genes are poorly understood both functionally and e... Whole genome duplication, a prevalent force of evolution in plants, results in massive genome restructuring in different organisms. Roles of the resultant duplicated genes are poorly understood both functionally and evolutionarily. In the present study, differentially expressed ethylene responsive factors(GhERF1 s), anchored on Chr-A07 and Chr-D07 were isolated from a high-yielding cotton hybrid(XZM2)and its parents. The GhERF1 was located in the B3 subgroup of the ethylene responsive factors subfamily involved in conferring tolerance to abiotic stress Nucleotide sequence analysis of 524 diverse accessions together with quantitative real-time polymerase chain reaction analysis, elucidated that de-functionalization of GhERF1-7 A occurred due to one base insertion following formation of the allotetraploid cotton. Our quantitative trait loci and association mapping analyses highlighted a role for GhERF1-7 A in conferring high boll number per plant in modern cotton cultivars. Overexpression of GhERF1-7 A in transgenic Arabidopsis resulted in a substantial increase in the number of siliques and total seed yield. Neo-functionalization of GhERF1-7 A was also observed in modern cultivars rather than in races and/or landraces, further supporting its role in the development of high-yielding cotton cultivars. Both de-and neofunctionalization occurred in one of the duplicate genes,thus providing new genomic insight into the evolution of allotetraploid cotton species. 展开更多
关键词 functional diversifications of Gh ERF1 duplicate genes after the formation of allotetraploid cotton
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Theoretical study on the formation mechanism of polychlorinated dibenzothiophenes/thianthrenes from 2-chlorothiophenol molecules 被引量:1
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作者 Xiaoqing Yu Jiamin Chang +2 位作者 Xian Liu Wenxiao Pan Aiqian Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第4期318-327,共10页
Homogeneous formation of polychlorinated dibenzothiophenes/thianthrenes(PCDT/TAs),sulfurated compounds analogous to polychlorinated dibenzo-p-dioxin/dibenzofurans(PCDD/Fs), has been well-documented to occur via ra... Homogeneous formation of polychlorinated dibenzothiophenes/thianthrenes(PCDT/TAs),sulfurated compounds analogous to polychlorinated dibenzo-p-dioxin/dibenzofurans(PCDD/Fs), has been well-documented to occur via radical–radical coupling reactions from chlorinated thiophenol precursors. However, the current understanding of the formation mechanism of PCDT/TAs is exclusively limited to the inherent point of view that chlorothiophenoxy radicals act as the only required intermediates for PCDT/TAs. This study investigates reaction pathways for the formation of PCDT/TAs involving two new types of radical species, i.e., substituted phenyl radicals and substituted thiophenoxyl diradicals. Taking 2-chlorothiophenol(2-CTP) as a model compound for chlorothiophenols,we found that apart from the mostly discussed chlorothiophenoxy radicals, substituted phenyl radicals and substituted thiophenoxyl diradicals could also be readily formed via the reaction of 2-CTP with H radicals. Furthermore, direct self-and cross-coupling of these radicals can result in the formation of PCDT/TAs, including 1-monochlorothianthrene(1-MCTA), 1,6-dichlorothianthrene(1,6-DCTA), 4,6-dichlorodibenzothiophene(4,6-DCDT)and 1,6-dichlorodibenzothiophene(1,6-DCDT). The pathways proposed in this work are proven to be both thermodynamically and kinetically favorable. Particularly, comparisons were made between the formation mechanisms of sulfurated and oxygenated dioxin systems from an energetic point view, showing that replacing oxygen with sulfur atoms greatly reduces the activation barriers of the rate-controlling steps involved in the PCDT/TA formation processes compared with those involved for PCDD/Fs. The calculated results in this work may improve our understanding of the formation mechanism of PCDT/TAs from chlorothiophenol precursors and should be informative to environmental scientists. 展开更多
关键词 Polychlorinated dibenzothiophenes/thianthrenes Formation mechanism Phenyl radicals Thiophenoxyl diradicals Density functional theory study
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