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Now showing items 17 - 32 of 63

  • Radon induced mitochondrial dysfunction in human bronchial epithelial cells and epithelial–mesenchymal transition with long-term exposure

    Xu, Qian   Fang, Lijun   Chen, Bin   Zhang, Hong   Wu, Qianqian   Zhang, Hongbo   Wang, Aiqing   Tong, Jian   Tao, Shasha   Tian, Hailin  

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  • Depression and Risk of Stroke A Meta-Analysis of Prospective Studies

    Dong, Jia-Yi   Zhang, Yong-Hong   Tong, Jian  

    Background and Purpose-A history of depression may be associated with an increased risk of stroke. We aimed to determine the association between depression and risk of stroke by performing a meta-analysis of prospective studies.Methods-Relevant studies were identified by a PubMed database search through May 2011 without restrictions and by reviewing reference lists of obtained articles. Community-based or population-based prospective studies that reported relative risk estimates with 95% confidence intervals for the association between depression and stroke were selected. Studies that enrolled participants with preexisting stroke at baseline were excluded. A random-effects model was used to compute the pooled risk estimate.Results-Random-effects meta-analysis of 17 prospective studies involving 206 641 participants and 6086 cases demonstrated a significant positive association between depression and subsequent risk of stroke (pooled relative risk, 1.34; 95% confidence interval, 1.17-1.54) after adjustment for potential confounding factors. The associations were similar between men and women. Potential publication bias may exist, but correction for this bias using a formal statistical method did not materially alter the combined risk estimate.Conclusions-Depression significantly increased the risk of development of stroke, and this increase was probably independent of other risk factors, including hypertension and diabetes. (Stroke. 2012;43:32-37.)
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  • Circadian rhythm genes mediate fenvalerate-induced inhibition of testosterone synthesis in mouse Leydig cells

    Guo, Yichen   Shen, Ouxi   Han, Jingjing   Duan, Hongyu   Yang, Siyuan   Zhu, Zhenghong   Tong, Jian   Zhang, Jie  

    Fenvalerate (Fen), a widely used pesticide, is known to impair male reproductive functions by mechanisms that remain to be elucidated. Recent studies indicated that circadian clock genes may play an important role in successful male reproduction. The aim of this study was to determine the effects of Fen on circadian clock genes involved in the biosynthesis of testosterone using TM3 cells derived from mouse Leydig cells. Data demonstrated that the circadian rhythm of testosterone synthesis in TM3 cells was disturbed following Fen treatment as evidenced by changes in the circadian rhythmicity of core clock genes (Bmal1, Rev-erba, Rora). Further, the observed altered rhythms were accompanied by increased intracellular Ca2+ levels and modified steroidogenic acute regulatory (StAR) mRNA expression. Thus, data suggested that Fen inhibits testosterone synthesis via pathways involving intracellular Ca2+ and clock genes (Bmal1, Rev-Erba, Rora) as well as StAR mRNA expression in TM3 cells.
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  • Ectopic expression of miR-34a enhances radiosensitivity of non-small cell lung cancer cells, partly by suppressing the LyGDI signaling pathway

    Duan, Weiming   Xu, Yaxiang   Dong, YuJin   Cao, Lili   Tong, Jian  

    miR-34a is transcriptionally induced by the tumor suppressor gene p53, which is often downregulated in non-small cell lung cancer (NSCLC). To address whether the downstream signal of miR-34a is sufficient to induce apoptosis and to alter cellular radiosensitivity, a chemical synthetic miR-34a mimic was delivered into A549 and H1299 cells, with or without co-treatment of gamma-irradiation. Results showed that ectopic expression of miR-34a induced dose-dependent cell growth inhibition and apoptosis in a p53-independent manner in both NSCLC cell lines. Interestingly, LyGDI was discovered as a new target gene of miR-34a, and downregulation of LyGDI promoted Rac1 activation and membrane translocation, resulting in cell apoptosis. Furthermore, restoration of miR-34a indirectly reduced cyclooxygenase-2 (COX-2) expression. Taken together, these results demonstrate that restoration of miR-34a expression enhances radiation-induced apoptosis, partly by suppressing the LyGDI signaling pathway, and miR-34a could possibly be used as a radiosensitizer for non-small cell lung cancer therapy.
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  • Radon-Induced Alterations in Micro-RNA Expression Profiles in Transformed BEAS2B Cells

    Cui, Feng-Mei   Li, Jian-Xiang   Chen, Qiu   Du, Hou-Bin   Zhang, Shu-Yu   Nie, Ji-Hua   Cao, Jian-Ping   Zhou, Ping-Kun   Hei, Tom K.   Tong, Jian  

    Radon and its progeny are confirmed to be type I carcinogenic agents accounting for increased risks in 10% of observed lung cancers globally. However, the underlying carcinogenic mechanisms are largely unknown. In the present study, BEAS2B cells were directly exposed twice to 20,000 Bq/m3 radon gas for 20 min once (first passage) and subsequently 10 times (fifth passage). The fifth-passage cells were then subcultured for 1 and 20 generations (named Rn5-1 and Rn5-20, respectively). Molecular mechanisms indicative of malignant transformation were assessed by determination of apoptosis, seroresistance, and microRNA (miRNA) expression profiles. The microRNA profiles were used to assess the functional annotations of the target genes. Data indicated an increased seroresistance and colony efficiency on soft agar, and enhanced apoptosis resistance in the Rn5-20 cells with significant differential expressions in some miRNA, including hsa-miR-483-3p, hsa-miR-494, hsa-miR-2115*, hsa-miR-33b, hsa-miR-1246, hsa-miR-3202, hsa-miR-18a, hsa-miR-125b, hsa-miR-17*, and hsa-miR-886-3p. Functional annotation demonstrated that these miRNA target genes were predominantly involved in the regulation of cell proliferation, differentiation, and adhesion during the process of malignant transformation, which is associated with signal pathways such as mitogen-activated protein kinase (MAPK), Int and Wg (Wnt), reactive oxygen species (ROS), nuclear factor ?B (NF-?B), and other genes regulating cell cycles.
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  • Study on the properties of amino acid ionic liquid EMIGly

    Yang, Jia-Zhen   Zhang, Qing-Guo   Wang, Bin   Tong, Jian  

    In terms of standard addition method, the density and surface tension of an amino acid ionic liquid EMIGly-(1-ethyl-3-methylimidazolium aminoacetate) were measured under dry argon atmosphere in the temperature range of 288.15-343.15 K. The properties of volume and surface for pure EMIGly were discussed in terms of the interstice model and Glasser's theory. The thermal expansion coefficient alpha = 5.03 x 10(-4) K-1 calculated using interstice model is in good agreement with alpha (experimental) 5.20 x 10(-4) K-1.
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  • Mechanisms underlying melatonin-mediated prevention of fenvalerate-induced behavioral and oxidative toxicity in zebrafish

    Han, Jingjing   Ji, Cheng   Guo, Yichen   Yan, Rui   Hong, Ting   Dou, Yuanyan   An, Yan   Tao, Shasha   Qin, Fenju   Nie, Jihua   Ji, Chen   Wang, Han   Tong, Jian   Xiao, Wei   Zhang, Jie  

    The neurotoxic effects attributed to the pesticide fenvalerate (FEN) are well-established. The aim of this study was to determine whether melatonin (MLT) was able to protect against FEN-induced behavior, oxidative stress, apoptosis, and neurogenesis using zebrafish (Danio rerio) model. Zebrafish exposed to 100 mu g/L FEN for 120 h exhibited decreased swimming activity accompanied by downregulated expression of neurogenesis-related genes (Dlx2, Shha, Ngn1, Elavl3, and Gfap), suggesting that neurogenesis were impaired. In addition, FEN exposure significantly elevated oxidative stress as evidenced by increased malondialdehyde levels, as well as activities of Cu/Zn superoxide dismutase (Cu/Zn SOD), catalase, and glutathione peroxidase. Acridine orange staining demonstrated that embryos treated with FEN for 120 h significantly enhanced apoptosis mainly in the brain. FEN also produced upregulation of the expression of the pro-apoptotic genes (Bax, Fas, caspase 8, caspase 9, and caspase 3) and decreased expression of the anti-apoptotic gene Bcl-2. MLT significantly attenuated the FEN-mediated oxidative stress, modulated apoptotic-regulating genes, and diminished apoptotic responses. Further, MLT blocked the FEN-induced effects on swimming behavior as well as on neurogenesis-related genes. In conclusion, MLT protected against FEN-induced developmental neurotoxicity and apoptosis by inhibiting pesticide-mediated oxidative stress in zebrafish.
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  • How Does Environmental Regulation Affect Industrial Transformation? A Study Based on the Methodology of Policy Simulation

    Liu, Wei   Tong, Jian   Yue, Xiaohang  

    The difference of factor input structure determines different response to environmental regulation. This paper constructs a theoretical model including environmental regulation, factor input structure, and industrial transformation and conducts a policy simulation based on the difference of influencing mechanism of environmental regulation considering industrial heterogeneity. The findings show that the impact of environmental regulation on industrial transformation presents comparison of distortion effect of resource allocation and technology effect. Environmental regulation will promote industrial transformation when technology effect of environmental regulation is stronger than distortion effect of resource allocation. Particularly, command-control environmental regulation has a significant incentive effect and spillover effect of technological innovation on cleaning industries, but these effects do not exist in pollution-intensive industries. Command-control environmental regulation promotes industrial transformation. The result of simulation showed that environmental regulation of market incentives is similar to that of command-control.
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  • Association of CLOCK gene variants with semen quality in idiopathic infertile Han-Chinese males

    Zhang, Jie   Ding, Xinliang   Li, Yingchun   Xia, Yankai   Nie, Jihua   Yi, Cao   Wang, Xinru   Tong, Jian  

    Recent experimental animal studies suggested that the circadian locomotor output cycles kaput protein gene (CLOCK) may play an important role in male reproduction. So far, such data for humans are not available. This study used single-nucleotide polymorphisms (SNP) to examine the association between CLOCK and semen quality in a human population with idiopathic infertility. Three-variant genotyping of CLOCK and semen analysis were performed in 478 men with idiopathic infertility by SNP genotyping assays and computer-aided sperm analysis. Subjects carrying a C allele at rs3749474 (CC and TC) presented significantly lower semen volume (P = <0.001 and 0.001, respectively) compared with the TT genotype. Subjects carrying the rs3749474 CC genotype had significantly lower sperm number per ejaculate (P = 0.026) and sperm motility (P = 0.021) than TT genotype carriers. rs1801260 TC genotype carriers had significantly lower sperm motility compared with the TT genotype (P = 0.028). For the rs3817444 genotypes, CA and AA genotype carriers presented significantly lower semen volume compared with the CC genotype (P = 0.022 and 0.001, respectively). The findings suggest, as far as is known for the first time, an association between CLOCK genetic variants and altered semen quality in a human population with idiopathic infertility. (C) 2012, Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
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  • A new approximate fast method of computing the scattering from multilayer rough surfaces based on the Kirchhoff approximation

    Tian, Jiasheng   Tong, Jian   Shi, Jian   Gui, Liangqi  

    In this paper a new approximate fast method of calculating the bistatic-scattering coefficients of a multilayer structure with random rough interfaces was presented based on the Kirchhoff Approximation (KA) and the electromagnetic theory of stratified media. First, the electromagnetic scattering from a Gauss rough metal or dielectric surface was calculated by KA method and method of moment (MOM), and the effectiveness of KA method was confirmed and verified. Second, a new approximate fast method was presented to calculate electromagnetic scattering from a multilayer-random-rough surface based on electromagnetic reflection from multilayer parallel surfaces and KA. The calculated results by the new method were in good agreements with those by MOM, especially near the specular point. Finally, a comparison of the new method and MOM was carried out in consuming computing time, memory resources, and complexity. The comparison indicated that the new approximate method was faster by about 30-150 times than MOM. The new approximate fast method could avoid a large matrix inversion and greatly reduce the computation time and memory resources and thus improve the computational efficiency. It was an effective approximation fast analyzing method of electromagnetic scattering from multilayer rough surfaces.
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  • lncRNA‑NR024118 overexpression reverses LPS‑induced inflammatory injury and apoptosis via NF‑κB/Nrf2 signaling in ATDC5 chondrocytes

    Mei, Xiaoliang   Tong, Jian   Zhu, Wei   Zhu, Yongliang  

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  • Direct Form I Active Optical Filters Realized in an Integrated Photonic Architecture

    MacFarlane, Duncan L.   Tong, Jian   Hunt, L. Roberts   Panahi, Issa   Wade, Kent   Evans, Gary A.   Christensen, Marc P.  

    A novel integrated photonic architecture is introduced and used to realize an optical filter with direct form I realization. The architecture offers gain from semiconductor optical amplifiers; and this gain results in an active optical filter whose filter response depends on the individual gains. The presence of gain provides advantages in filter performance; and tunable and adaptive functionality. The optical filter is modeled as a discrete time system and the z-transform is used in its analysis and design. A low-pass filter design example is presented and the filter coefficients are derived in terms of gains and coupler splitting ratios. The region of stable operations is derived by applying the Schur-Cohn stability test.
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  • Circadian alterations of reproductive functional markers in male rats exposed to 1800MHz radiofrequency field.

    Qin, Fenju   Zhang, Jie   Cao, Honglong   Guo, Weiqiang   Chen, Lili   Shen, Ouxi   Sun, Jinpeng   Yi, Cao   Li, Jianxiang   Wang, Jiajun   Tong, Jian  

    In this study, we explored the circadian effects of daily radiofrequency field (RF) exposure on reproductive functional markers in adult male Sprague-Dawley rats. Animals in circadian rhythm (as indicated by melatonin measurements), were divided into several groups and exposed to 1800MHz RF at 205muw/cm(2) power density (specific absorption rate 0.0405W/kg) for 2h/day for 32days at different zeitgeber time (ZT) points, namely, ZT0, ZT4, ZT8, ZT12, ZT16 and ZT20. Sham-exposed animals were used as controls in the study. From each rat, testicular and epididymis tissues were collected and assessed for testosterone levels, daily sperm production and sperm motility, testis marker enzymes gamma-GT and ACP, cytochrome P450 side-chain cleavage (p450cc) mRNA expression, and steroidogenic acute regulatory protein (StAR) mRNA expression. Via these measurements, we confirmed the existence of circadian rhythms in sham-exposed animals. However, rats exposed to RF exhibited a disruption of circadian rhythms, decreased testosterone levels, lower daily sperm production and sperm motility, down-regulated activity of gamma-GT and ACP, as well as altered mRNA expression of cytochrome P450 and StAR. All of these observations were more pronounced when rats were exposed to RF at ZT0. Thus, our findings indicate potential adverse effects of RF exposure on male reproductive functional markers, in terms of both the daily overall levels as well as the circadian rhythmicity. =20
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  • 1800MHz radiofrequency fields inhibits testosterone production via CaMKI /RORalpha pathway.

    Qin, Fenju   Cao, Honglong   Yuan, Hongxia   Guo, Weiqiang   Pei, Hailong   Cao, Yi   Tong, Jian  

    Exposure to radiofrequency fields (RF) has been reported to induce adverse effects on testosterone production and its daily rhythm. However, the mechanisms underneath this effect remain unknown. In this study, male mice were exposed to 1800MHz radiofrequency fields (RF, 40 muW/cm2 power intensity and 0.0553W/Kg SAR) 2h per day for 32 days. The data suggested that RF exposure: (i) significantly reduced testosterone levels, (ii) altered the expression of genes involved in its synthesis (Star, P450scc, P450c17 and 3beta-Hsd) in testicular tissue, (iii) significantly reduced regulatory protein CaMKI/RORalpha. Similar observations were also made in cultured primary Leydig cells exposed in vitro to RF. However, all of these observations were blocked by CaMK inhibitor, KN-93, and ionomycin reversed the down-regulation effects on intracellular [Ca2+]i and CaMKI/RORalpha expression induced by RF exposure. Thus, the data provided the evidence that RF-induced inhibition of testosterone synthesis might be mediated through CaMKI/RORalpha signaling pathway. Capsule: CaMKI/RORalpha signaling pathway was involved in the inhibition of testosterone synthesis induced by RF exposure. Copyright =C2=A9 2018 Elsevier Inc. All rights reserved.
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  • Structure and inclusion behaviour of five supramolecular inclusion solids constructed from flexible organic layers with [Fe(CN)(6)](3-) as pillars by second-sphere coordination

    Guo, Fang   Li, Lei   Zhang, Yi-Ning   Tong, Jian   Song, Chun-Liang   Xia, Fang   Guo, Wen-Sheng  

    In the paper, a series of new pillar-layered supramolecular complexes have been built up through second-sphere coordination. Three N, N, N', N'-tetrabenzyl diamine ligands [N, N, N', N'-tetrabenzyl-ethylenediamine (L1), N, N, N', N'-tetrabenzyl- 2-butyne-1,4-diamine (L2) and N, N, N', N'-tetrabenzyl-(p-xylylene)-diamine (L3)] were synthesised, and can react with [Fe(CN)(6)](3) via second-sphere coordination, yielding pillar-layered supramolecular complexes, [H(2)L1] 0.5.[Fe(CN)(6)](0.5) superset of 0.5H(3)O.1.5H(2)O (Crystal 1), [H(2)L2](0.25)center dot[Fe(CN)(6)](0.25) superset of 0.5H(3)O.0.5H(2)O (Crystal 2) and [H(2)L3]center dot[Fe(CN)(6)] superset of Cl.ethylene glycol center dot H2O (Crystal 3). The 3D networks are organic layers formed by the self-assembly of the ligands through extensive hydrogen-bonding interactions (pi ... pi stacking or C-H ... pi interactions) and further interconnected by [Fe(CN)(6)](3-) in a pillar fashion, constructing into pillar-layered networks with channels accessible to various guest molecules. The inclusion property of [H(2)L1] u [Fe(CN)(6)] was studied; varieties of guest molecules, such as ethanol and tetrahydrofuran, can be included in the framework and lead to the formation of different inclusion complexes [H(2)L1].[Fe(CN)(6)]. (guest)(n) (crystal 1, 4-5).
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  • Densities and Viscosities of Aqueous Amino Acid Ionic Liquids [C(n)mim][Ala](n=3D3,4,5)

    Tong, Jing   Zheng, Xu   Li, Hui   Tong, Jian   Liu, Qingshan  

    Amino acid ionic liquids [C(n)mim] [Ala] (n =3D 3, 4, 5) (1-alkyl-3-methylimidazolium alanine salt) were prepared by the neutralization method. The density and viscosity for aqueous solutions of the ionic liquids (ILs) with various molalities were measured at T =3D (288.15 to 328.15), K with an interval of 5 K. In terms of the Jones Dole equation, the viscosity B-coefficients with large positive values and dB/dT < 0 were obtained, and these facts implied that the ionic liquids are water-structure-making. According to Feakins, the contribution of the solute per mole to the free energy of activation for viscous flow of the solution, Delta mu(double dagger 0)(2), or called as the standard molar activation free energy, was obtained at different temperatures. Under the constant molality of solution, Delta H-2(double dagger 0) (the activation enthalpy of the activation for viscous flow of aqueous [C(n)mim][Ala] (n =3D 3, 4, 5)) is a temperature-independent constant. This implies that the activation process of the solute for viscous flow of aqueous [C(n)mim] [Ala] (n =3D 3, 4, 5) is an isoCoulombic reaction. A semiempirical method to estimate the viscosity of aqueous [C(n)mim] [Ala] (n =3D 3, 4, 5) was put forward based on Eyring's theory, and the estimated viscosity values of the aqueous ILs are in good agreement with the corresponding experimental ones.
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