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Influenza is a respiratory virus that alone or in combination with secondary bacterial pathogens can contribute to the development of acute pneumonia in persons >65 years of age. Host innate immune antiviral signaling early in response to influenza is essential to inhibit early viral replication and guide the initiation of adaptive immune responses. Using young adult (3 months) and aged adult mice infected with mouse adapted H1N1 or H3N2, the results of our study illustrate dysregulated and/or diminished activation of key signaling pathways in aged lung contribute to increased lung inflammation and morbidity. Specifically, within the first seven days of infection, there were significant changes in genes associated with TLR and RIG-I signaling detected in aged murine lung in response to H1N1 or H3N2. Taken together, the results of our study expand our current understanding of age-associated changes in antiviral signaling in the lung.  相似文献   

3.
段天宝  曲黎  叶文玉 《应用化工》2006,35(11):867-870
在醇-水体系中,以H4S iMo12O40和哌嗪为原料制备了组成为(C4H10N2H)3HS iMo12O40的纳米颗粒,以透射电子显微镜(TEM)、扫描电子显微镜(SEM)、X射线粉末衍射仪(XRD)、傅立叶变换红外光谱仪(FT-IR)、紫外可见分光光度计(UV)、热分析仪(TG-DTA)等测试手段,对纳米颗粒的形貌、组成和结构进行了表征,并在机械式四球长时抗磨损试验机上考察了其摩擦学性能。分散型实验结果表明,化合物在有机溶剂中良好分散(除乙醚外),红外/紫外光谱和X射线粉末衍射表明,所合成的纳米颗粒具有杂多酸Keggin骨架结构无机核,透射电镜分析表明,颗粒平均粒径约为10 nm,热分析显示分解温度范围为200~425℃,作为新型有机/无机复合纳米润滑油添加剂,最佳添加浓度为0.35%时,在测试条件为负荷294 N,时间30 m in,转速1450 r/m in条件下,使磨斑直径减小22.7%,摩擦系数减小14%。  相似文献   

4.
Fish oils are used as therapeutic agents in chronic inflammatory diseases. The omega-3 fatty acids (FA) found in these oils are mainly eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. The anti-inflammatory properties of fish oils are attributed to both omega-3 fatty acids. However, it is unknown whether such effects are due to either EPA or DHA. In this study, the effects of EPA and DHA on rat neutrophil function in vitro were compared. Both EPA and DHA increased the production of H2O2 when cells were stimulated or not with lipopolysaccharides (LPS). However, EPA was more potent than DHA in triggering an increase in superoxide release by cells in the basal condition or when stimulated with phorbol myristate acetate (PMA) or zymosan. Only DHA increased the phagocytic capacity and fungicidal activity of neutrophils. Both FA increased the release of tumor necrosis factor-α (TNF-α) in nonstimulated cells, but only EPA increased the production of cytokine-inducing neutrophil chemoattractant-2 (CINC-2) in the absence or presence of LPS, whereas production of interleukin-1 beta (IL-1β) was only increased by DHA in the presence of LPS. In addition, there was no alteration in the production of nitric oxide. In conclusion, we show herein that EPA and DHA can differently modulate aspects of the neutrophil response, which may be relevant for the development of therapies rich in one or other FA depending on the effect required.  相似文献   

5.
A single-step complex decomposition method for the synthesis of bulk and alumina-supported γ-Mo2N catalysts is described. The complex precursor (HMT)2(NH4)4Mo7O24·2H2O (HMT: hexamethylenetetramine) is converted to γ-Mo2N under a flow of Ar in a temperature range of 823–1023 K. Furthermore, decomposition of the precursor in a NH3 flow forms γ-Mo2N in a temperature range of 723–923 K. Compared with direct decomposition of the precursor in Ar, the reaction in NH3 shows obvious advantages that the nitride forms at a lower temperature. In addition, alumina-supported γ-Mo2N catalysts with different nitride loadings can be prepared from the alumina-supported complex precursor in the Ar or NH3 flow. The resultant catalysts exhibit good dibenzothiophene HDS activities, which are similar to the γ-Mo2N/γ-Al2O3 prepared by traditional TPR method. The catalyst prepared by decomposition in an Ar flow exhibits highest activity. It proves that such a single-step complex decomposition method possesses the potential to be a general route for the preparation of molybdenum nitride catalysts.  相似文献   

6.
The aim of this study was to analyze the expression of peroxisome proliferator-activated receptor γ (PPARγ) and retinoid X receptor α (RxRα), a binding heterodimer playing a pivotal role in the successful trophoblast invasion, in the placental tissue of preeclamptic patients. Furthermore, we aimed to characterize a possible interaction between PPARγ and H3K4me3 (trimethylated lysine 4 of the histone H3), respectively H3K9ac (acetylated lysine 9 of the histone H3), to illuminate the role of histone modifications in a defective trophoblast invasion in preeclampsia (PE). Therefore, the expression of PPARγ and RxRα was analyzed in 26 PE and 25 control placentas by immunohistochemical peroxidase staining, as well as the co-expression with H3K4me3 and H3K9ac by double immunofluorescence staining. Further, the effect of a specific PPARγ-agonist (Ciglitazone) and PPARγ-antagonist (T0070907) on the histone modifications H3K9ac and H3K4me3 was analyzed in vitro. In PE placentas, we found a reduced expression of PPARγ and RxRα and a reduced co-expression with H3K4me3 and H3K9ac in the extravillous trophoblast (EVT). Furthermore, with the PPARγ-antagonist treated human villous trophoblast (HVT) cells and primary isolated EVT cells showed higher levels of the histone modification proteins whereas treatment with the PPARγ-agonist reduced respective histone modifications. Our results show that the stimulation of PPARγ-activity leads to a reduction of H3K4me3 and H3K9ac in trophoblast cells, but paradoxically decreases the nuclear PPARγ expression. As the importance of PPARγ, being involved in a successful trophoblast invasion has already been investigated, our results reveal a pathophysiologic connection between PPARγ and the epigenetic modulation via H3K4me3 and H3K9ac in PE.  相似文献   

7.
以N-甲基苯胺为起始原料,经过环合反应制得4-羟基-1-甲基-2(1H)-喹啉酮,再经硝化和氯代反应合成了目标化合物,该方法所用原料廉价易得,产物处理简单,适合工业化生产,总收率可达51.9%。  相似文献   

8.
Copper-nickel phosphides/ graphite-like phase carbon nitride (Cu3P-Ni2P/g-C3N4) composites were obtained through a facile one-pot in situ solvothermal approach. The coexistence of Cu3P and Ni2P plays an important role in enhancing the catalytic activity of g-C3N4. The 7 wt% Cu3P-Ni2P/g-C3N4 bimetallic phosphide photocatalyst demonstrates the best photocatalytic hydrogen (H2) evolution rate of 6529.8 μmol g−1 h−1, which is 80.7-fold higher than that of g-C3N4. The apparent quantum yield (AQE) was determined to be 18.5% at 400 nm over the 7% Cu3P-Ni2P/g-C3N4. This in situ growth strategy produced intimate contact interfaces, leading to a significantly promoted separation of charge carriers, and hence strengthened the photocatalytic H2 production. Moreover, the coexistence of Cu3P and Ni2P reduced the overpotential of H2 during the evolution process, further benefiting H2 production. Finally, the photocatalytic enhancement mechanism was proposed and verified by fluorescence and electrochemical analysis. This work provides a low-cost strategy to synthesize nonprecious bimetallic phosphides/carbon nitride photocatalyst with outstanding H2 production activity. © 2020 Society of Chemical Industry  相似文献   

9.
The effect of seeding on the microstructural development and mechanical properties of sintered reaction-bonded silicon nitride was investigated by the use of β-Si3N4 particles. Seeding of an appropriate amount of the β-Si3N4 particles gave rise to the promotion of density and the resulting increase in fracture strength and hardness. The fracture toughness was also increased due to the development of elongated grains. On the other hand, addition of a large amount of seed particles showed lower strength and fracture toughness owing to the coalescence of large elongated grains. By seeding of 2 wt.% β-Si3N4 particles on Si powders of 7 μm, high fracture strength of 1100 MPa and fracture toughness of 7.2 MPa·m1/2 were obtained in sintered reaction-bonded silicon nitride ceramics.  相似文献   

10.
标题化合物(SYP-298)是沈阳化工研究院的试验除草剂,由邻硝基苯甲酸经5步反应制得。其结构经核磁共振谱和质谱分析确证。SYP-298在温室条件下38 g a.i./hm2可防多种阔叶杂草,在600 g a.i./hm2对玉米和水稻安全。  相似文献   

11.
对3,4-二氢-2(1H)喹啉酮衍生物1,2,3(R= NO2,NH2,OH;R= H,NO2,NH2)的合成进行了研究。以苯胺和3-氯丙酰氯为原料,制得N-苯基-3-氯丙酰胺,然后经环合得到3,4-二氢-2(1H)喹啉酮,再经由硝化、还原、重氮化水解合成了一系列3,4-二氢-2(1H)喹啉酮衍生物:6-硝基-3,4-二氢-2(1H)喹啉酮(1a),6,8-二硝基-3,4-二氢-2(1H)喹啉酮(1b),6-氨基-3,4-二氢-2(1H)喹啉酮(2a),6,8-二氨基-3,4-二氢-2(1H)喹啉酮(2b),6-氨基-8-硝基-3,4-二氢-2(1H)喹啉酮(2c),6-羟基-3,4-二氢-2(1H)喹啉酮(3a)和6-羟基-8-硝基-3,4-二氢-2(1H)喹啉酮(3b),其中化合物(2c)及(3b)为新化合物。单步产率均在86%以上,路线简单,操作简便,反应条件温和。采用MS,1HNMR对产品进行了定性及结构表征。  相似文献   

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Conjugated linoleic acid (CLA) is thought to have anti-proliferative and anti-inflammatory properties, but its effect on cancer cachexia is unknown. Two effects were here investigated: that of CLA on inflammatory mediator production in human lung cancer cells, and that of reduced mediators on the myogenic differentiation of murine muscle C2C12 cells. The latter cells were grown in medium conditioned by human lung cancer A427 cells, with or without CLA, to mimic only the effect of molecules released from the tumor “in vivo”, excluding the effect of host-produced cachectic factors. The results obtained show that CLA was found to reduce the production of tumor necrosis factor-α, interleukin (IL)-1β and prostaglandin E2 (PGE2), but had no effect on IL-6 production. The mechanisms underlying the effect of CLA on cytokine or PGE2 release in A427 cells are probably mediated by activation of peroxisome proliferator-activated receptor (PPAR)α, which increased at 24 h CLA treatment. In turn, the reduced content of inflammatory mediators in medium conditioned by A427 cells, in the presence of CLA, allowed muscle cells to proliferate, again by inducing PPAR. The involvement of PPARα was demonstrated by treatment with the antagonist MK-886. The findings demonstrate the anti-inflammatory and myogenic action of CLA and point to its possible application as a novel dietary supplement and therapeutic agent in inflammatory disease states, such as cachexia.  相似文献   

14.
In the present study the derivatization of two water‐soluble synthetic polymers, α,β‐poly(N‐2‐hydroxyethyl)‐DL ‐aspartamide (PHEA) and α,β‐polyasparthylhydrazide (PAHy), with glycidyltrimethylammonium chloride (GTA) is described. This reaction permits the introduction of positive charges in the macromolecular chains of PHEA and PAHy in order to make easier the electrostatic interaction with DNA. Different parameters affect the reaction of derivatization, such as GTA concentration and reaction time. PHEA reacts partially and slowly with GTA; on the contrary the reaction of PAHy with GTA is more rapid and extensive. The derivatization of PHEA and PAHy with GTA is a convenient method to introduce positive groups in their chains and it permits the preparation of interpolyelectrolyte complexes with DNA. © 2000 Society of Chemical Industry  相似文献   

15.
An efficient and divergent one‐pot synthesis of substituted 2H‐pyrans, 4H‐pyrans and pyridin‐2(1H)‐ones from β‐oxo amides based on the selection of the reaction conditions is reported. Mediated by N,N,N′,N′‐tetramethylchloroformamidinium chloride, β‐oxo amides underwent intermolecular cyclizations in the presence of triethylamine at room temperature to give substituted 2H‐pyrans in high yields, which could be converted into substituted 4H‐pyrans in the presence of sodium hydroxide in ethanol at room temperature, or into substituted pyridin‐2(1 H)‐ones under reflux.  相似文献   

16.
Herein, we disclose the N‐heterocyclic carbene (NHC)‐catalyzed [3+3] annulation of challenging esters with methyl ketoimines for the highly enantioselective synthesis of intriguing δ‐lactams featuring various substituent patterns. The annulation occurs under mild conditions and offers good tolerance, good yields and excellent enantioselectivities. The six‐membered heterocyclic products are valuable for the synthesis of bioactive molecules.

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17.
综述了1,2-苯并异噻唑-3(2H)-酮-2-正丁基-1,1-二氧化物的研究进展,并评价了各方法的优缺点,提出了改进方向。  相似文献   

18.
目的构建双亚型(H3/H1)流感病毒血凝素(HA)基因真核表达质粒,并在HeLa细胞中进行表达。方法通过PCR分别改造流感病毒H1亚型HA1和H3亚型HA基因片段,在融合片段间引入(G4S)3柔性linker和口蹄疫病毒2A蛋白linker。采用DNAstar结合生物信息学软件InsightⅡ分析后,对其空间构象进行模拟。将H1HA1-H3HA融合基因片段克隆至真核表达载体pVAX1 CMV启动子下游。通过脂质体法转染HeLa细胞,RT-PCR法检测转染细胞中目的基因mRNA的转录,间接免疫荧光检测转染细胞中目的蛋白的表达。结果表达双亚型(H3/H1)流感病毒血凝素基因的重组真核表达质粒pVAX1-H3HA-H1HA1经酶切和测序证明构建正确。转染重组质粒的HeLa细胞可检测到目的基因mRNA的转录和目的蛋白的表达。结论已成功构建了真核表达质粒pVAX1-H3HA-H1HA1,并可在HeLa细胞中正确转录与表达,为H3、H1亚型流感病毒双价核酸疫苗的研究奠定了基础。  相似文献   

19.
胡立志  钱利  孙晨  袁艳琴 《化学试剂》2011,33(4):369-372
以硅胶磺酸(SiO2-SO3H)为催化剂,4-芳硫基芳醛、1,3-环己二酮及醋酸铵为原料,于乙醇中合成了标题化合物.该方法具有处理方便、反应时间短、产率高、催化剂价廉易得、可回收重复使用等优点.  相似文献   

20.
Nd1.95NiO4+δ (NNO) cathode supported microtubular cells were fabricated and characterized. This material presents superior oxygen transport properties in comparison with other commonly used cathode materials. The supporting tubes were fabricated by cold isostatic pressing (CIP) using NNO powders and corn starch as pore former. The electrolyte (GDC, gadolinia doped ceria based) was deposited by wet powder spraying (WPS) on top of pre‐sintered tubes and then co‐sintered. Finally, a NiO/GDC suspension was dip‐coated and sintered as the anode. Optimization of the cell fabrication process is shown. Power densities at 750 °C of ∼40 mWcm−2 at 0.5V were achieved. These results are the first electrochemical measurements reported using NNO cathode‐supported microtubular cells. Further developments of the fabrication process are needed for this type of cells in order to compete with the standard microtubular solid oxide fuel cells (SOFC).  相似文献   

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