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We have previously shown that tumor necrosis factor-α (TNF-α), which is an important angiogenesis-related factor, was over-secreted in male BALB/c mice under social isolation stress as compared with the control, and closely associated with a remarkable elevation of tumor invasion and metastasis of colon 26-L5 carcinoma cells. In the present study, we explored the effect of isolation stress on the angiogenesis caused by colon 26-L5 carcinoma cells in vivo and in vitro. Social isolation lead to the enhancement of tumor growth after intrahepatic implantation with a fragment of colon 26-L5 tumor. Angiogenic response (number of vessels oriented towards tumor mass) and tumor growth (size) were significantly increased in the socially isolated mouse relative to that in the group-housed mice. Furthermore, higher protein level of hepatic TNF-α was found in the stressed mice than that in the control. Expression of mRNA for vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were also elevated in the tumor regions and liver tissues of the stressed mice in comparison with that in group-housed mice. On the other hand, hepatic sinusoidal endothelial (HSE) cells treated with TNF-α exhibited a marked promotion of the migration, invasion, expression of mRNA for matrix metalloproteinase (MMP)-9, and tube-like formation, but no cytotoxicity against the cells in vitro. The above data suggest that the social isolation stress augmented the tumor-induced angiogenesis probably by up-regulating the angiogenesis-related factors, including TNF-α, VEGF and HGF, and consequently mediating the functions of endothelial cells such as migration, invasion, and tube-like formation.  相似文献   
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UNC93B1存在于内质网上,具多次跨膜区域,它能与TLR(Toll-like receptors,TLRs)-3,-7,-9发生特异性结合并将它们从内质网上运输(trafficking)至溶酶体中。UNC93B1与TLRs相互作用并通过MyD88/TRIF途径进行着信号传递。TLRs通过识别相应的高度保守的病原相关分子模式(PAMPs),在介导防御外来微生物入侵的先天性免疫反应并桥连或触发获得性免疫反应中起重要作用。在3d(N-乙基-N-亚硝基脲诱导的染色体基因的隐性突变)小鼠中,UNC93B1上H412R位点的突变阻断了其和TLRs的结合,进而阻碍了TLRs信号的传递,这使得该小鼠易被各种病原体感染。另外,UNC93B1的突变阻止了小鼠体内抗原的交叉呈递途径,也降低了MHC-II类分子呈递途径。UNC93B1缺陷使得人体易受单纯疱疹病毒I型(HSV-1)病毒感染而引起单纯疱疹病毒1型脑炎(HSE)。此外,通过调节UNC93B1和TLR7/9的接触可控制或避免系统性红斑狼疮、关节炎等自身性免疫疾病的发生。  相似文献   
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In this study, the structure and coordination environment of two 3d transition elements (Ni and Cr) is investigated in a molten chloride salt system. Electronic absorption spectroscopy was employed to elucidate their coordination environment in 3LiCl-2KCl eutectic salt, as a function of temperature. Density functional theory (DFT) modeling was used to determine the coordination environment of the transition metal species in the eutectic composition as well as the optical spectra computationally. The Ni2+and Cr3+ exist in a tetrahedral and octahedral coordination environment, respectively, in eutectic salt. The spectra thus obtained were compared with the experimental data; a reasonable qualitative agreement was obtained between experimental and computational Ni2+ and Cr3+spectra, and the coordination of both elements in the eutectic composition were in excellent agreement with the experimentally determined results. Computational results were also obtained for two 4d elements, Mo3+ and Nb3+, with both quantum molecular dynamics (QMD) and hybrid functional optical spectra indicating octahedral coordination.  相似文献   
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Chemokines are important in HSE development in the CNS but underlying regulatory events are unknown. Two-hybrid binding assays identified that intercellular adhesion molecule 5 (ICAM-5), an immune modulator in the CNS, interacted with neurovirulence factor, UOL, of HSV-1. Viral load and interleukin levels were similar in UOL deletion virus (ΔUOL), and wild type virus infected mouse brains. However, higher numbers of lymphocytes, but unaltered soluble ICAM-5 and chemokine levels were detected in ΔUOL infected mouse brains. In contrast, lower lymphocyte numbers, reduced soluble ICAM-5, and higher chemokine levels were detected in wild type virus infected brains. Our results suggest that ICAM-5 plays a critical role in modulating chemokine production in the CNS.  相似文献   
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作业安全分析是一种有效的控制作业风险的工具。概述了作业安全分析的概念与实施。运用JSA对进入污水沉淀池作业进行安全分析,阐述作业安全分析对于实现HSE管理目标的重要作用和实践方法。  相似文献   
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目的 探讨凋亡素下调HepG2细胞热休克蛋白70 (HSP70)的分子机制.分析凋亡素与HSP70启动子区热休克元件(HSE)的相互结合作用.方法 应用凝胶电泳迁移率分析(EMSA)法检测凋亡素与HSE的结合;荧光素酶报告基因实验进一步分析凋亡素在细胞内与HSE的结合能力.结果 EMSA结果表明凋亡素在体外和细胞水平可以直接与HSP70启动子区的HSE结合,凋亡素浓度越高,与HSE结合能力越强;Luciferase报告基因结果显示凋亡素对HSE具有专一的结合能力,揭示在与HSE结合上,凋亡素与HSF1间存在竞争关系.结论 凋亡素与HSP70启动子区HSE序列结合,抑制HSP70转录的起始,显著下调HSP70的表达,解除HSP70对肿瘤细胞的保护作用,诱导肿瘤细胞的凋亡.  相似文献   
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Phototoxicity and photoallergy in man   总被引:2,自引:0,他引:2  
Photosensitivity is the broad term used to denote adverse reactions to the sun. These reactions may be phototoxic or photoallergic. Phototoxic reactions are much more common than photoallergic reactions. Phototoxic reactions may be photodynamic or nonphotodynamic in nature, the primary difference being that photodynamic reactions require oxygen. Porphyrins are examples of molecules which produce photodynamic responses. The 8-methoxypsoralen photobinding to DNA is an example of a nonphotodynamic reaction. The UVB sunburn response is the most common phototoxic reaction, and it appears to be nonphotodynamic in nature. Photoallergy is uncommon. As with all allergies it is an acquired, altered reactivity dependent on an antigen-antibody or cell-mediated hypersensitivity response. Solar urticaria due to UVB rays is an example of a circulating antibody-dependent reaction, and allergic photocontact dermatitis induced by the halogenated salicylanilides is an example of a cell-mediated response. The mechanisms of these reactions are discussed.  相似文献   
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We have created a totally synthetic, protein-free surfactant (Exosurf) composed of dipalmitoylphosphatidylcholine, hexadecanol, and tyloxapol. We studied the effects of endotracheal instillation of Exosurf on survival and pulmonary function of preterm lambs delivered at 131 to 133 days gestation (term 148 days). Exosurf treatment was compared with instillation of surface-active material prepared from lung lavages of adult sheep and with no instillation. Lambs were delivered by cesarean section, paralyzed, and mechanically ventilated. The Exosurf group survived longer (80% alive at 11 hours) than did the no instillation group (30% alive at 11 hours) (P less than 0.05). There were no statistically significant differences between the Exosurf and sheep surfactant groups. We conclude that Exosurf, a synthetic surfactant, produces significant improvement in survival and pulmonary function in preterm lambs.  相似文献   
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