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941.
Yuki Kawakami Shiori Hirano Mai Kinoshita Akemi Otsuki Toshiko Suzuki-Yamamoto Makiko Suzuki Masumi Kimoto Sae Sasabe Mitsuo Fukushima Koji Kishimoto Takashi Izumi Toru Oga Shuh Narumiya Mitsuaki Sugahara Masashi Miyano Shozo Yamamoto Yoshitaka Takahashi 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
Cysteinyl leukotrienes (LTs) are key mediators in inflammation. To explore the structure of the antigen-recognition site of a monoclonal antibody against LTC4 (mAbLTC), we previously isolated full-length cDNAs for heavy and light chains of the antibody and prepared a single-chain antibody comprising variable regions of these two chains (scFvLTC).Methods
We examined whether mAbLTC and scFvLTC neutralized the biological activities of LTC4 and LTD4 by competing their binding to their receptors.Results
mAbLTC and scFvLTC inhibited their binding of LTC4 or LTD4 to CysLT1 receptor (CysLT1R) and CysLT2 receptor (CysLT2R) overexpressed in Chinese hamster ovary cells. The induction by LTD4 of monocyte chemoattractant protein-1 and interleukin-8 mRNAs in human monocytic leukemia THP-1 cells expressing CysLT1R was dose-dependently suppressed not only by mAbLTC but also by scFvLTC. LTC4- and LTD4-induced aggregation of mouse platelets expressing CysLT2R was dose-dependently suppressed by either mAbLTC or scFvLTC. Administration of mAbLTC reduced pulmonary eosinophil infiltration and goblet cell hyperplasia observed in a murine model of asthma. Furthermore, mAbLTC bound to CysLT2R antagonists but not to CysLT1R antagonists.Conclusions
These results indicate that mAbLTC and scFvLTC neutralize the biological activities of LTs by competing their binding to CysLT1R and CysLT2R. Furthermore, the binding of cysteinyl LT receptor antagonists to mAbLTC suggests the structural resemblance of the LT-recognition site of the antibody to that of these receptors.General significance
mAbLTC can be used in the treatment of inflammatory diseases such as asthma. 相似文献942.
Aberrant mucin O-glycosylation often occurs in different cancers and is characterized by immature expression of simple mucin-type carbohydrates. At present, there are some controversial reports about the Tn antigen (GalNAcα-O-Ser/Thr) expression and there is a great lack of information about the [UDP-N-acetyl-α-d-galactosamine:polypeptide N-acetylgalactosaminyltransferase (GalNAc-Ts)] expression in chronic lymphocytic leukemia (CLL). To gain insight in these issues we evaluated the Tn antigen expression in CLL patient samples using two Tn binding proteins with different fine specificity. We also studied the expression from 14 GalNAc-Ts genes in CLL patients by RT-PCR. Our results have provided additional information about the expression level of the Tn antigen, suggesting that a low density of Tn residues is expressed in CLL cells. We also found that GALNT11 was expressed in CLL cells and normal T cell whereas little or no expression was found in normal B cells. Based on these results, GALNT11 expression was assessed by qPCR in a cohort of 50 CLL patients. We found significant over-expression of GALNT11 in 96% of B–CLL cells when compared to normal B cells. Moreover, we confirmed the expression of this enzyme at the protein level. Finally we found that GALNT11 expression was significantly associated with the mutational status of the immunoglobulin heavy chain variable region (IGHV), [?2(1) = 18.26; P < 0.0001], lipoprotein lipase expression [?2(1) = 13.72; P = 0.0002] and disease prognosis [?2(1) = 15.49; P < 0.0001]. Our evidence suggests that CLL patient samples harbor aberrant O-glycosylation highlighted by Tn antigen expression and that the over-expression of GALNT11 constitutes a new molecular marker for CLL. 相似文献
943.
944.
硫对土壤重金属形态转化及植物有效性的影响研究进展 总被引:2,自引:1,他引:1
生源要素硫在土壤中的化学循环不仅会直接影响土壤重金属元素的环境行为,也可通过调控植物根际微环境间接影响植物对重金属元素的吸收累积.土壤中的硫被植物根吸收后在植株中合成的有机硫化合物如植物螯合素(PCs)和金属硫蛋白(MTs)可与重金属形成毒性较低的络合物,构成植物重金属解毒的重要机制之一.我国部分土壤缺硫现象严重,为保证作物高质高产,硫肥的使用逐渐被重视,而硫与重金属的交互作用机制也逐渐成为研究热点.本文综合相关研究,介绍了硫在土壤中的生物化学转化,探讨了土壤硫的化学转化对土壤重金属形态转化及植物有效性的影响,并对今后硫在土壤重金属控制的应用提出展望.
相似文献
945.
946.
Jennifer Heine Steffen Krüger Christoph Hartnig Ulrich Wietelmann Martin Winter Peter Bieker 《Liver Transplantation》2014,4(5)
Safety issues caused by the metallic lithium inside a battery represent one of the main reasons for the lack of commercial availability of rechargeable lithium‐metal batteries. The advantage of anodes based on coated lithium powder (CLiP), compared to plain lithium foil, include the suppression of dendrite formation, as the local current density during stripping/plating is reduced due to the higher surface area. Another performance and safety advantage of lithium powder is the precisely controlled mass loading of the lithium anode during electrode preparation, giving the opportunity to avoid Li excess in the cell. As an additional benefit, the coating makes electrode manufacturing safer and eases handling. Here, electrodes based on coated lithium powder electrodes (CLiP) are introduced for application in lithium‐metal batteries. These electrodes are compared to lithium foil electrodes with respect to cycling stability, coulombic efficiency of lithium stripping/plating, overpotential, and morphology changes during cycling. 相似文献
947.
Nanoparticles: A Light Harvesting Antenna Using Natural Extract Graminoids Coupled with Plasmonic Metal Nanoparticles for Bio‐Photovoltaic Cells (Adv. Energy Mater. 18/2014)
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948.
Linking Vertical Bulk‐Heterojunction Composition and Transient Photocurrent Dynamics in Organic Solar Cells with Solution‐Processed MoOx Contact Layers
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It is demonstrated that a combination of microsecond transient photocurrent measurements and film morphology characterization can be used to identify a charge‐carrier blocking layer within polymer:fullerene bulk‐heterojunction solar cells. Solution‐processed molybdenum oxide (s‐MoOx) interlayers are used to control the morphology of the bulk‐heterojunction. By selecting either a low‐ or high‐temperature annealing (70 °C or 150 °C) for the s‐MoOx layer, a well‐performing device is fabricated with an ideally interconnected, high‐efficiency morphology, or a device is fabricated in which the fullerene phase segregates near the hole extracting contact preventing efficient charge extraction. By probing the photocurrent dynamics of these two contrasting model systems as a function of excitation voltage and light intensity, the optoelectronic responses of the solar cells are correlated with the vertical phase composition of the polymer:fullerene active layer, which is known from dynamic secondary‐ion mass spectroscopy (DSIMS). Numerical simulations are used to verify and understand the experimental results. The result is a method to detect poor morphologies in operating organic solar cells. 相似文献
949.
950.