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Interleukin-33 is a newly described member of the interleukin-1 family. Recent research suggests that IL-33 is increased in lungs and plays a critical role in chronic airway inflammation in cigarette smoke-induced chronic obstructive pulmonary disease (COPD) mice. To determine the role of IL-33 in systemic inflammation, we induced COPD mice models by passive cigarette smoking and identified the IL-33 expression in bronchial endothelial cells and peripheral blood mononuclear cells (PBMCs) of them. After isolation, PBMCs were cultured and stimulated in vitro. We measured expressions of interleukin-6 and interleukin-8 in PBMCs in different groups. The expression of IL-33 in bronchial endothelial cells and PBMCs of COPD mice were highly expressed. Stimulated by cigarette smoke extract (CSE), the expression of IL-6 and IL-8 were induced and enhanced by IL-33. PBMCs of COPD mice produced more IL-6 and IL-8 stimulated by CSE and IL-33. Expression of IL-6 and IL-8 were decreased when stimulated by IL-33 together with soluble ST2. The mRNA production of ST2 in IL-33 stimulated PBMCs was increased. Being pretreated with several kinds of MAPK inhibitors, the secretions of IL-6 and IL-8 in PBMCs did not decrease except for the p38 MAPK inhibitor. We found that IL-33 could induce and enhance the expression of IL-6 and IL-8 in PBMCs of COPD mice via p38 MAPK pathway, and it is a promoter of the IL-6 and IL-8 production in systemic inflammation in COPD mice.  相似文献   
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A taxonomic study was carried out on strain 22II-S11-z10T, which was isolated from the surface seawater of the Atlantic Ocean. The bacterium was found to be Gram-stain negative, oxidase and catalase positive, oval- to rod-shaped and non-motile. Growth was observed at salinities of 0.5–9 % and at temperatures of 10–41 °C. The isolate can reduce nitrate to nitrite, degrade gelatin and aesculin, but can not degrade Tween 80. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 22II-S11-z10T belongs to the genus Actibacterium, with the highest sequence similarity to the type strain Actibacterium mucosum CECT 7668T (97.3 %). The DNA–DNA hybridization estimate value between strain 22II-S11-z10T and A. mucosum CECT 7668T was 19.30 ± 2.29 %. The principal fatty acids were identified as Summed Feature 8 (C18:1 ω7c/ω6c as defined by the MIDI system, 75.2 %) and Summed Feature 3 (C16:1 ω7c/ω6c, 6.9 %). The G+C content of the chromosomal DNA was determined to be 59.0 mol%. The respiratory quinone was determined to be Q-10 (100 %). Phosphatidylglycerol, phosphatidylcholine, two phospholipids, two aminolipids and two lipids were identified in the polar lipids. The combined genotypic and phenotypic data show that strain 22II-S11-z10T represents a novel species within the genus Actibacterium, for which the name Actibacterium atlanticum sp. nov. is proposed, with the type strain 22II-S11-z10T (=MCCC 1A09298T = LMG 27158T).  相似文献   
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Scorpion toxin Ctri9577, as a potent Kv1.3 channel blocker, is a new member of the α-KTx15 subfamily which are a group of blockers for Kv4.x potassium channels. However, the pharmacological function of Ctri9577 for Kv4.x channels remains unknown. Scorpion toxin Ctri9577 was found to effectively inhibit Kv4.3 channel currents with IC50 value of 1.34 ± 0.03 μM. Different from the mechanism of scorpion toxins as the blocker recognizing channel extracellular pore entryways, Ctri9577 was a novel gating modifier affecting voltage dependence of activation, steady-state inactivation, and the recovery process from the inactivation of Kv4.3 channel. However, Ctri9755, as a potent Kv1.3 channel blocker, was found not to affect voltage dependence of activation of Kv1.3 channel. Interestingly, pharmacological experiments indicated that 1 μM Ctri9755 showed less inhibition on Kv4.1 and Kv4.2 channel currents. Similar to the classical gating modifier of spider toxins, Ctri9577 was shown to interact with the linker between the transmembrane S3 and S4 helical domains through the mutagenesis experiments. To the best of our knowledge, Ctri9577 was the first gating modifier of potassium channels among scorpion toxin family, and the first scorpion toxin as both gating modifier and blocker for different potassium channels. These findings further highlighted the structural and functional diversity of scorpion toxins specific for the potassium channels.  相似文献   
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摘要:【目的】筛选可产生抗血栓活性物质的细菌。【方法】利用VY/4平板、酪蛋白平板从水样、土样、兔粪、羊粪、朽木等20多个样品中筛选目的菌株;利用纤维蛋白平板和纤维蛋白试管检测抗血栓活性;利用形态学特征、理化性质、16S rRNA序列同源性鉴定目的菌株。【结果】得到5株可产生抗血栓活性物质的细菌,重点研究了菌株LDS33,发现其分泌的胞外蛋白在纤维蛋白平板上和纤维蛋白试管中均显示出强烈的溶栓活性,通过试管法发现此蛋白质同时具有较强的抗凝活性。结合形态学、理化性质、16S rDNA序列及进化树分析,发现该菌株属于硬壁菌门芽孢杆菌目芽孢杆菌科芽孢杆菌属的短小芽孢杆菌,将其命名为Bacillus pumilus LDS.33。【结论】短小芽孢杆菌LDS33可产生高活性的抗凝溶栓双活性蛋白。  相似文献   
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A series of color‐tunable Ca3–2x‐y‐zSiO4Cl2 (CSC):xCe3+,xLi+,yMn2+,zEu2+ phosphors with low temperature phase structure was synthesized via the sol–gel method. An energy transfer process from Ce3+ to Mn2+ in CSC:0.01Ce3+,0.01Li+,yMn2+ (y = 0.03–0.09) and the mechanism was verified to be an electric dipole–dipole interaction. The Ce3+ and Mn2+ emission intensities were greatly enhanced by co‐doping Eu2+ ions into CSC:0.01Ce3+,0.01Li+,0.07Mn2+ phosphors due to competitive energy transfers from Eu2+/Ce3+ to Mn2+, and Ce3+ to Eu2+. Under 332 nm excitation, CSC:0.01Ce3+,0.01Li+,0.07Mn2+,zEu2+ (z = 0.0005–0.002) exhibited tunable emission colors from green to white with coexisting orange, green and violet‐blue emissions. These phosphors could have potential application in white light‐emitting diodes.  相似文献   
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中国特有植物银杉林的现状和未来   总被引:9,自引:0,他引:9  
银杉是我国特有的珍稀植物,仅在四川、贵州、湖南和广西四省区残存。其地理分布可归结为大娄山、越城岭、八面山和大瑶山等4个集积地。现有的银杉林全部为混交林,主要有7个类型:银杉-甜槠混交林、银杉-石栎混交林、银杉-亮叶桦混交林、银杉-广东五针松混交林、银杉-长苞铁杉混交林、银杉-大明松混交林及银杉-南方铁杉-福建柏混交林。银杉处于优势地位,群落相对稳定,但银杉更新不良。在自然演替中,阔叶树种的入侵对银杉构成严重威胁,最终将会取代银杉。为了保护银杉,在林地对阔叶树进行透光伐,在林窗人工移植银杉幼苗幼树是必要的。  相似文献   
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铅锌砷复合污染对水稻生长的影响   总被引:15,自引:0,他引:15  
谢正苗  黄昌勇 《生态学报》1994,14(2):215-217
铅锌砷复合污染对水稻生长的影响谢正苗,黄昌勇(浙江农业大学土化系杭州,310029)EFFECTSOFCOMBINEDPOLLUTIONOFLEADZINCARSENICONRICEGROWTHXieZhengmiaoHunagChangyong(Z...  相似文献   
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