48 resultados para IL-23


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采用软件分析选择与IL-4分子结合与活性相关的重要位点13T,121R,通过定点突变得到IL-4突变基因cpIL4(13D121E),将其与绿脓杆菌外毒素突变基因PE38KDEL融合,成功地构建了编码免疫毒素cpIL4(13D121E)-PE38KDEL的融合基因.该基因在原核表达系统中得到了高效表达,表达量占细胞全蛋白的30%以上.表达产物经亲和色谱和阴离子交换色谱纯化后,进行细胞毒性实验,证明其对表达型IL-4受体的淋巴瘤细胞Daudi具有良好的细胞毒作用,活性是同类型IL-4免疫毒素的2倍,而对表达型IL-4受体的内皮细胞活性较低.

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Chemically converted graphene (CCG)/3,4,9,10-perylene tetracarboxylic acid (PTCA)/Au-ionic liquid (Au-IL) composites (CCG/PTCA/Au-IL) have been prepared by a chemical route that involves functionalization of CCG with PTCA followed by deposition of Au-IL. Transmission electron microscopy revealed well-distributed Au with a high surface coverage. The identity of the hybrid material was confirmed through X-ray diffraction and X-ray photoelectron spectroscopy. The CCG/PTCA/Au-IL composites exhibited good electrocatalytic behavior toward oxygen reduction. The results indicate that modification of CCG with Au-IL could play an important role in increasing the electrocatalytic activity of CCG.

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The hydrophobic carbon nanotubes-ionic liquid (CNTs-IL) get forms a stable modified film on hydrophobic graphite electrode surface. Laccase immobilized on the CNTs-IL gel film modified electrode shows good thermal stability and enhanced electrochemical catalytic ability. The optimal bioactivity occurs with increasing temperature and this optimum is 20 degrees C higher in comparison to free laccase. The improvement of laccase thermal stability may be due to the microenvironment of hydrophobic CNTs-IL gel on graphite electrode surface. On the other hand, the sensitive detection of oxygen has been achieved due to the feasibility of oxygen reduction by both of laccase and nanocomposite of CNTs-IL gel. Furthermore, the laccase hybrid nanocomposite also shows the fast electrochemical response and high sensitivity to the inhibitors of halide ions with the approximate IC50 of 0.01, 4.2 and 87.5 mM for the fluoride, chloride and bromide ions, respectively. It implies the feasibility of laccase modified electrode as an inhibition biosensor to detect the modulators of laccase.

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Multiwall carbon nanotubes (CNTs)-modified electrode has been prepared by using ionic liquid (IL) as the binder. The as-prepared CNTs-IL composite modified electrode has good biocompatibility and is a suitable matrix to immobilize biomolecules. Glucose oxidase (GOx), containing flavin adenine dinucleotide as active site, stably adsorbed on modified electrode surface has resulted in the direct electron transfer. The electron transfer rate of 9.08 s(-1) obtained is much higher than that of GOx adsorbed on the CNTs papers (1.7 s(-1)), and the process is more reversible with small redox peak separation of 23 mV This may be due to the synergetic promotion of CNTs and IL to electron transfer of the protein, especially the IL as the binder, showing better electrochemical properties than that of chitosan and Nafion. Furthermore, GOx adsorbed at the modified electrode exhibits good stability and keeps good electrocatalytic activity to glucose with broad linear range up to 20 mM. Besides, the simple preparation procedure and easy renewability make the system a basis to investigate the electron transfer kinetics and biocatalytic performance of GOx and provide a promising platform for the development of biosensors.

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CE/tris(2,2-bipyridyl) ruthenium(ll) (Ru(bpy)(3)(2+)) electrochemiluminescence (ECL), CEECL, with an ionic liquid (IL) detection system was established for the determination of bioactive constituents in Chinese traditional medicine opium poppy which contain large amounts of coexistent substances. A minimal sample pretreatment which involves a one-step extraction approach avoids both sample loss and environmental pollution. As the nearby hydroxyl groups in some alkaloid such as morphine may react with borate to form complexes and IL, as a high-conductivity additive in running buffer, could cause an enhanced field-amplified effect of electrokinetic injection. Running buffer containing 25 mM borax-8 mM 1-ethyl-3-methylimidazolium tetrafluoroborate (EMImBF(4)) IL (pH 9.18) was used which resulted in significant changes in separation selectivity and obvious enhancement in ECL intensities for those alkaloids with similar structures. Sensitive detection could be achieved when the distance between the Pt working electrode and the outlet of separation capillary was set at 150 mu m and the stainless steel cannula was fixed approximately 1 cm away from the outlet of the capillary. Quantitative analysis of four alkaloids was achieved at a detection voltage of 1.2 V and a separation voltage of 15 kV in less than 7 min.

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研究了两亲聚合物聚 (2 -丙烯酰胺基十六烷磺酸 ) (PAMC16S)存在下 1 -乙基 -3 ,3 -二甲基螺 [吲哚啉 -萘并口恶嗪 ](SO -E)在水溶液中的增溶作用及PAMC16S对SO -E化学和光化学性质的影响。PAMC16S明显增加了SO -E在水相的溶解性 ,SO -E的最大增溶浓度随PAMC16S浓度增加呈线性增加规律。在PAMC16S存在下 ,新配制的SO -E溶液显示可逆的光致变色性 ,显色体呈红色 ,最大吸收峰位于 5 2 0nm ,在室温下的消色反应速度明显慢于无PAMC16S存在下的兰色显色体。SO -E/PAMC16S溶液是不稳定的 ,配制后较长时间即失去SO -E的正常光致变色性质。盐酸具有与PAMC16S相似的作用 ,SO -E/PAMC16S体系的不稳定性可用氨水中和的方法解决。1H -NMR结果表明SO -E在酸性介质中发生了不可逆的化学反应。

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利用 ̄(23)Na作为探针磁核,通过弛豫分析发现:稀土离子与HSA络合后使蛋白质分子体积膨胀,链段活动性增加,表现为相关时间(τ_c)减小;HSA可能至少有了3个高亲和位点可络合稀土离子;稀土离子诱导的HSA动态结构变化在某种程度上具有可逆性,即当高亲和位上的稀土离子被螯合剂在取后,膨胀伸展的结构趋于恢复原有状态。

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以谷胱甘肽作为病毒包络蛋白的模拟物,用NMR方法研究了与具有抗爱滋病病毒活性杂多酸HPA-23的作用.对不同配比的HPA-23和谷胱甘肽混合物的1H和183WNMR谱研究结果表明,还原型和氧化型谷胱甘肽均以C末端COO-与HPA-23骨架的钨原子配位,还原型谷胱甘肽侧链上的巯基(SH)也参加配位.COSY谱证明了SH配位为慢交换反应.早在七十年代初,人们就发现杂多酸具有抗病毒活性[1,2].最近报道[NH4]18[NaSb9W21O88]·24H2O(结构代号为HPA-23)具有很高的抗爱滋病病毒活性,在法国已进入临床应用[3].但从分子水平研究杂多酸化合物抗病毒的机理.目前尚未见到国内外报道.而作为病毒可以广义地看作由一个蛋白外壳包裹,内部则为核酸.爱滋病病毒同样由两层蛋白所包裹,与宿主细胞发生吸附作用主要是通过外层包络蛋白(GP120)[4],该蛋白的活性组份是一个由8个氨基酸组成的T(Ala-Ser-Thr-Thr-Thr-Asn-Tyr-Thn)肽段[5].我们以容易得到的三肽一谷胱甘肽作为病毒包络蛋白的模拟物,用NMR方法研究杂多酸HPA-23与它的作用.结果表明还原型和氧化型谷胱甘肽均以C末端C

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早在70年代初,人们就发现杂多酸具有抗病毒活性.例如钨锑酸钠[NaSb_9W_(21)O_(86)]~(18-)有可能成为潜在的抗病毒化合物.非常有趣的是最近报道[NH_4]_(18)[NaSb_9W_(21)O_(86)]·24H_2O(结构代号为HPA-23)具有很高的抗爱滋病病毒活性,在法国已进入临床应用.但从分子水平研究杂多酸化合物抗病毒的机理,目前尚未见到国内外报道.而作为病毒可以广义地看作由一个蛋白外壳包裹,内部则为核酸.爱滋病病毒同样由两层蛋白所包裹,与宿主细胞发生吸附作用主要是通过外层包络蛋白(GP120),该蛋白的活性组分是一个由8个氨基酸组成

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The interleukin 1beta (IL-1beta) cDNA was cloned from the red seabream (Pagrus major) by homology cloning strategy. A cDNA fragment was amplified by PCR using two degenerated primers, which were designed according to the conserved regions of other known IL-1beta sequences, and elongated by 3' ends and 5' ends RACE PCR to get the full length coding sequence of red seabream IL-1beta (RS IL-1beta). The sequence contained 1252 nucleotides that included a 5' untranslated region (UTR) of 84 bp, a 3' UTR of 410 bp and an open reading frame (ORF) of 759 nucleotides which could be translated into a putative peptide of 253 amino acids with molecular weight of 28.6 kD and putative isoelectric point pI of 5.29. The deduced peptide contained two potential N-glycosylation sites and an identifiable IL1 family signature, but lacked the signal peptide and the clear ICE cut site, which were common in other nonmammalian IL-1beta genes. The RS IL-1beta had the highest homology with piscine IL-1beta according to phylogenetic tree analysis. The transcript expression was detected in blood, brain, gill, heart, head kidney, kidney, liver, muscle and spleen in the pathogen challenged and healthy red seabream by RTPCR. Results showed that the RS IL-1beta mRNA was constitutively expressed in most of the tissues both in stimulated and un-stimulated fish, and the expression could be enhanced by pathogen challenging.

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Myeloid differentiation factor 88 (MyD88) is a universal and essential adapter for the TLR/IL-1R family. In this report, the first mollusk Myd88 ortholog (named as CfMyd88) was cloned from Zhikong scallop (Chlamys farreri). The full-length cDNA of CfMyd88 was of 1554 bp, including a 5 '-terminal untranslated region (UTR) of 427 bp, a polyA tail, and an open reading frame (ORF) of 1104 bp encoding a polypeptide of 367 amino acids containing the typical TLR and IL-1R-related (TIR) domain and death domain (DD). Homology analysis revealed that the predicted amino acid sequence of CfMyd88 was homologous to a variety of previously identified Myd88s with more than 30% identity. The temporal expressions of CfMyd88 mRNA in the mixed primary cultured haemocytes stimulated by lipopolysaccharide (LPS) and peptidoglycans (PGN) were measured by real-time RT-PCR system. The mRNA expression of CfMyd88 decreased after stimulation with both LPS and PGN, and the lowest level was about 1/3 times (at 6 h) and 1/10 times (at 9 h) to that in the control group, respectively. The expression then recovered and was upregulated to two-fold at 9 h after LPS stimulation or to the original level at 12 It after PGN stimulation. The results suggest that the MyD88-dependent signaling pathway exists in scallop and was involved in the defense system. (c) 2007 Elsevier Ltd. All rights reserved.

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Toll-like receptors (TLRs) are an ancient family of pattern recognition receptors, which show homology with the Drosophila Toll protein and play key roles in detecting various non-self substances and then initiating and activating immune system. In this report, the full length of the first bivalve TLR (named as CfToll-1) is presented. CfToll-1 was originally identified as an EST (expressed sequence tag) fragment from a cDNA library of Zhikong scallop (Chlamys farreri). Its complete sequence was obtained by the construction of Genome Walker library and 5' RACE (rapid amplification of cDNA end) techniques. The full length cDNA of CfToll-1 consisted of 4308 nucleotides with a polyA tail, encoding a putative protein of 1198 amino acids with a 5' UTR (untranslated region) of 211 bp and a 3'UTR of 500 bp. The predicted amino acid sequence comprised an extracellular domain with a potential signal peptide, nineteen leucine-rich repeats (LRR), two LRR-C-terminal (LRRCT) motifs, and a LRR-N-terminal (LRRNT), followed by a transmembrane segment of 20 amino acids, and a cytoplasmic region of 138 amino acids containing the Toll/IL-1R domain (TIR). The deduced amino acid sequence of CfToll-1 was homologous to Drosophila melanogaster Tolls (DmTolls) with 23-35% similarity in the full length amino acids sequence and 30-54% in the TIR domain. Phylogenetic analysis of CfToll-1 with other known TLRs revealed that CfToll-1 was closely related to DmTolls. An analysis of the tissue-specific expression of the CfToll-1 gene by Real-time PCR showed that the transcripts were constitutively expressed in tissues of haemocyte, muscle, mantle, heart, gonad and gill. The temporal expressions of CfToll-1 in the mixed primary cultured haemocytes were observed after the haemocytes were treated with 1 mu g ml(-1) and 100 ng ml(-1) lipopolysaccharide (LPS), respectively. The expression of CfToll-1 was up-regulated and increased about 2-fold at 6 h with the treatment of 1 mu g ml(-1) LPS. The expression of CfToll-1 was down-regulated with the treatment of 100 ng ml(-1) LPS. The results indicated that the expression of CfToll-1 could be regulated by LPS, and this regulation was dose-dependent. (c) 2006 Elsevier Ltd. All rights reserved.

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地幔平衡部分熔融过程中,微量元素在原始岩浆中(熔体)和初始固相母体物质中(地幔)遵循以下关系:C^iL/C^oL=1/[D+F(1-D)];分离结晶成因的岩浆岩系,微量元素在残余岩浆中(C^iL)和母岩浆中(C^oL)遵循如下关系式:C^iL=C^iL*F^D-1。微量元素在部分熔融和分离结晶成岩方式中有独立的分布规律,因此利用微量元素对或比值的图解就可判别岩体(或脉岩)的成岩方式。选取微量元素Th-Yb、La-La/Yb、Th-Cr和Th-Ni图解对闽西基性脉岩成岩方式进行判别,发现闽西三个地区的基性脉岩均为地幔部分熔融作用所致,从而印证了闽西基性脉岩不是酸性岩浆演化的产物。

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伟晶岩形成和演化中岩浆-热液过渡阶段物理化学性质、过铝质富挥发分岩浆体系岩浆液相不混溶、流体相出溶事件的相对时间尺度以及在岩浆-热液过渡阶段体系中稀土和其它微量元素地球化学行为(稀土“四重效应”机制和微量元素分异及控制因素等)是目前过铝质岩浆体系研究的焦点问题。对上述问题的研究和探讨,将有助于了解伟晶岩形成和演化的全过程,有助于了解挥发分(H_20、F、B、P)对过铝质岩浆体系物理性质以及对REE和其它微量元素地球化学行为影响,这对于理解过铝质岩浆体系成岩、成矿作用过程具有重大的理论和实际意义。本论文选择著名的新疆阿尔泰3号伟晶岩脉为研究对象,由于它具有完美的分带特征,使我们有可能通过各结构带矿物学、地球化学的研究揭示伟晶岩成因和演化过程以及讨论岩浆-热液过渡阶段体系中的稀土和微量元素地球化学行为。由于LCT型伟晶岩具有明显的分带性、矿物颗粒大小不均匀性等特点,因此利用全岩样品研究伟晶岩往往因取样没有代表性而被大多数岩石学家和地球化学家所否定。考虑到这点,本文系统采集阿尔泰3号伟晶岩脉各结构带磷灰石、电气石、碱性长石、石英矿物,部分结构带的石榴石、绿柱石、锂辉石矿物以及伟晶岩冷凝边和蚀变围岩的全岩样品,通过各结构带磷灰石矿物化学组成和~(87)Sr/~(86)Sr比值测定,电气石矿物的化学组成和硼同位素组成分析,碱性长石中磷含量的电子探针分析和碱性长石-石英矿物对的氧同位素体系研究以及蚀变围岩和冷凝边的化学组成分析,本文较为详尽系统地探讨以上所有的问题。通过本次多年的研究,我们获得了以下几点新的认识:f1) 富挥发分过铝质岩浆体系的样品存在稀土“四重效应”和Y-Ho、Zr-Hf、Nb-Ta、Sr-Eu元素对的显著分异,表明在过铝质岩浆演化过程中含氟流体相起着重要的作用;目前,稀土“四重效应”机制被认为是含水流体相与过铝质岩浆熔体相互作用的结果(Irber 1999;Bau 1997),而不是独居石、磷钇矿、石榴石矿物等矿物的早期结晶引起的残余熔体稀土含量的异常变化。由于阿尔泰3号伟晶岩脉各带磷灰石以及与其共生的石榴石、绿柱石、碱性长石、锂辉石矿物均存存明显的稀土“四重效应”以及相同电价、相似离子半径的不相容元素间存在显著的分异,并结合最近赵振华等(1999)和Sba and Chappell(1999)报道S型花岗岩全岩和单矿物(磷灰石、独居石、长石、黄玉等)均存在稀土“四重效应”这一现象,本文研究提出,稀土“四重效应”是富挥发分过铝质岩浆体系的一个基本特征,其机制既不可能由含稀土的副矿物早期结晶引起残余熔体相中REE含量变化的结果,也不能定性地归因于流体相与熔体相相互作用过程中稀土元素在流体/熔体之间分异的结果,而很可能与伟晶岩岩浆形成之前某些过程密切相关,S型花岗岩岩浆在液相线以上存在硅酸盐熔体与高盐熔体(或卤水相)的不混溶液相分离有可能是过铝质岩浆体系产生稀土“四重效应”的主要原因。(2) 由于Sr~(2+)与Eu~(2+)具有相同的电价、相似的离子半径,根据经典的地球化学原理,它们具有相似的地球化学行为,在各种地质过程中其它们具有紧密的一致性。阿尔泰3号伟晶岩磷灰石中Sr/Eu比值具有二歧变化现象,其中I、Il、III和IV带磷灰石具有低的Sr/Eu比值(16:0~111.2),而V、VI、VII带、核部带和IV带中的一个磷灰石则显示较大的Sr/Eu比值(主要在246.6~514:9范围,其中IV带的一个磷灰石该比值在10000以上)。对世界范围内的过铝质花岗岩统计表明,过铝质岩浆岩的全岩样品中的Sr/Eu也呈现二歧变化,由此本文提出Sr/Eu比值是指示过铝质岩浆体系中岩浆流体相出溶的有效地球化学参数,大于300的Sr/Eu比值是Eu~(2+)强烈分配进入流体相的地球化学标志。(3) 阿尔泰3号伟晶岩I、II、III带电气石矿物的硼同位素组成(δ~(11)B)分布在-41.11‰~-30.90‰之间,V、VI、VII带电气石矿物硼同位素组成(δ~(11)B)在-15.23‰~-9.20‰范围,IV带电气石硼同位素分布于-39.19~13.10‰范围,如此大的硼同位素分馏无法根据实验研究获得的熔体/流体相间的分馏系数进行合理解释。我们的研究表明岩浆成因电气石的B同位素组成与电气石化学组成具相关性,随电气石Y位上AI、Li阳离子数的增大,δ~(11)B值显示明显增大的趋势。阿尔泰3号伟晶岩最初形成的结构带中电气石的B同位素组成是目前所发现的最低值之一(-41.1l~39.01‰),指示形成伟晶岩脉的初始岩浆可能由含非海相蒸发岩的泥质岩经变质深熔作用形成,或是伟晶岩岩浆在上侵定位过程中同化了含非海相蒸发岩地层的结果。本次研究利用电气石-白云母和电气石-四硼酸盐矿物间的同位索分馏以及熔体相-流体相间的同位索分馏,合理解释了阿尔泰3号伟晶岩脉电气石B同位素分馏过程,并首次获得伟晶岩形成、演化过程中B同位素组成演化的全程图谱。(4)伟晶岩岩浆形成和演化过程是否存在由过磷引起的液相不混溶现象未见确凿的岩石学和实验地球化学证据。阿尔泰3号伟晶岩脉糖粒状钠长石带(II带)明显由两种不同组构的岩性组成,而且该带是3号脉主要的Be矿化带,也是P、REE最重要的沉淀场所。阿尔泰3号伟晶岩脉梳状结构带和I带的碱性长石具较高P含量(平均值分别为0.42 wt%和0.22 wt%),随着岩浆的演化进行,从III带到核部带,碱性长石中P含量逐渐增大(平均值由0.21 wt%增至0.50 wt%),而II带碱性长石中异常低的P含量(平均值为0.08、wt%)是该带大量磷灰石矿物饱和结晶,导致残余熔体相中P极度亏损所造成的,而不是晚期出溶的岩浆热液交代形成的。根据Watson (1978)、Ryerson and Hess(1980)在液相线以上温度下实验研究获得的微量元素在不混溶的基性和酸性液相中分配特征,以及Webster et a1.(1997)对德国Ehrenfriedersdorf矿区伟晶岩石英中熔体包裹体的研究成果,我们推断在富磷岩浆体系中,在其演化的早期将出现由磷引起的液相不混溶作用,它对伟晶岩成岩和Be的成矿具有重大的影响。