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1.
Interleukin-1βconverting enzyme: A novel cysteine protease required for IL-1β production and implicated in programmed cell death 下载免费PDF全文
Nancy A. Thornberry Susan M. Molineaux 《Protein science : a publication of the Protein Society》1995,4(1):3-12
Interleukin-1β converting enzyme is the first member of a new class of cysteine proteases. The most distinguishing feature of this family is a nearly absolute specificity for cleavage at aspartic acid. This enzyme has been the subject of intense research because of its role in the production of IL-1β, a key mediator of inflammation. These studies have culminated in the design of potent inhibitors and determination of its crystal structure. The structure secures the relationship of the enzyme to CED-3, the product of a gene required for programmed cell death in Caenorhabditis elegans, suggesting that members of this family function in cell death in vertebrates. 相似文献
2.
Protected cultivation of ornamental flowers, as a commercial venture, becomes less profitable with excessive use of fertilizers. The present study examined the influence of microbial biofilm inoculants (Anabaena–Azotobacter, Anabaena–Trichoderma and Trichoderma–Azotobacter) on the availability of soil nutrients and structure of rhizosphere microbial communities in three varieties of chrysanthemum (var. White Star, Thai Chen Queen and Zembla). Varietal-specific responses in growth, enzyme activities, flower yield of plants and availability of soil nutrients were recorded. Dehydrogenase activity was highest in var. White Star treated with the Anabaena–Trichoderma biofilm inoculants. The Anabaena–Azotobacter inoculant enhanced the availability of nitrogen, phosphorus and micronutrients in the soil, besides 40–50% increase in soil organic carbon, as compared to carrier alone or no inoculation. PCR-DGGE profiling of the cyanobacterial communities and qPCR quantification of 16S rRNA abundance of bacteria, archaea and cyanobacteria in the rhizosphere soils, revealed the stronger influences of these inoculants, especially in var. Zembla. Principal Component Analysis (PCA) helped to illustrate that the enhanced microbe-mediated availability of soil macro-and micronutrients, except iron content (Fe), was the most influential factor facilitating improved plant growth and yield parameters. The Anabaena–Azotobacter, and Anabaena–Trichoderma biofilm inoculants, proved superior in all three chrysanthemum varieties. 相似文献
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目的:研究优质护理模式对心肌梗死康复期患者心理障碍及不良情绪的影响程度,旨在为康复期患者护理方式的选取提供理论依据。方法:将本院2014年1月~2014年12月的70例心肌梗死康复期患者遵照随机数字表法分为对照组和观察组各35例,对照组采用常规的康复护理进行干预,观察组则以优质护理理念为指导进行护理干预,然后将两组护理前和护理后2周、4周及8周的心理障碍及不良情绪状态采用SECD6量表及HAD量表进行评估,并将评估结果进行比较。结果:观察组护理后2周、4周及8周的SECD6量表及HAD量表评估结果均明显优于对照组,P均0.05,均有显著性差异。结论:优质护理模式对心肌梗死康复期患者治疗信心及不良情绪的影响相对更为积极,为患者康复治疗的顺利进行奠定了基础。 相似文献
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《Bioorganic & medicinal chemistry》2014,22(1):141-147
A series of new sulfonamides was prepared starting from 2-oxo-N′-(4-sulfamoylphenyl)-propanehydrazonoyl chloride, a sulfanilamide derivative, which was reacted with aroylhydrazides, amines, or thiols. A library of derivatives incorporating aroylhydrazone, [1,2,4]triazolo[3,4-b][1,3,4]thiadiazinyl- or 2-(cyanophenyl-methylene)-1,3,4-thiadiazol-3(2H)-yl moieties was thus synthesized. The new compounds were investigated as inhibitors of four α-carbonic anhydrases (CAs, EC 4.2.1.1), the human (h) isoforms hCA I and II, and the bacterial ones recently isolated from the extremophilic bacteria Sulfurihydrogenibium yellostonense (SspCA) and Sulfurihydrogenibium azorense (SazCA). Low nanomolar activity was observed against hCA II (KIs of 0.56–17.1 nM) whereas hCA I was less inhibited by these compounds (KIs of 86.4 nM–32.8 μM). The bacterial CAs were also effectively inhibited by these derivatives (KIs in the range of 0.77–234 nM against SazCA, and of 6.2–89.1 against SspCA, respectively), with several low nanomolar/subnanomolar inhibitors detected against both of them. As SspCA and SazCA are among the most thermostable and catalytically active CAs, it is of interest to find modulators of their activity for potential biotechnologic applications. 相似文献
6.
Fast protein liquid chromatography on Superose 6 of crude extracts from Chlorella kessleri, Fott et Novákóva, grown autotrophically in blue or in red light yields three different oligomeric forms of phosphofructokinase (PFK, EC 2.7.1.11). Their substrate affinities and responses to homotropic and heterotropic effectors are different. In vitro, the degree of oligomerization of the enzyme can be influenced by specific intermediates or cofactors. Its substrate, MgATP (10 mM/5 mM), and the negative effector, phosphoenolpyruvate (5 mM), both lead to some dissociation, while the second substrate, fructose-6-phosphate (5 mM), and the positive effector, inorganic phosphate (50 mM), have no effect. It is discussed whether formation or dissociation of oligomeric PFK forms in vivo result from alterations in the levels or in the intracellular distribution of effector molecules and whether such processes are involved in the different regulation of cell metabolism in blue or in red light. 相似文献
7.
Plant Molecular Biology - 相似文献
8.
Harjot K. Saini-Chohan Michael G. Holmes Adam J. Chicco William A. Taylor Russell L. Moore Sylvia A. McCune Diane L. Hickson-Bick Grant M. Hatch Genevieve C. Sparagna 《Journal of lipid research》2009,50(8):1600-1608
Cardiolipin (CL) is responsible for modulation of activities of various enzymes involved in oxidative phosphorylation. Although energy production decreases in heart failure (HF), regulation of cardiolipin during HF development is unknown. Enzymes involved in cardiac cardiolipin synthesis and remodeling were studied in spontaneously hypertensive HF (SHHF) rats, explanted hearts from human HF patients, and nonfailing Sprague Dawley (SD) rats. The biosynthetic enzymes cytidinediphosphatediacylglycerol synthetase (CDS), phosphatidylglycerolphosphate synthase (PGPS) and cardiolipin synthase (CLS) were investigated. Mitochondrial CDS activity and CDS-1 mRNA increased in HF whereas CDS-2 mRNA in SHHF and humans, not in SD rats, decreased. PGPS activity, but not mRNA, increased in SHHF. CLS activity and mRNA decreased in SHHF, but mRNA was not significantly altered in humans. Cardiolipin remodeling enzymes, monolysocardiolipin acyltransferase (MLCL AT) and tafazzin, showed variable changes during HF. MLCL AT activity increased in SHHF. Tafazzin mRNA decreased in SHHF and human HF, but not in SD rats. The gene expression of acyl-CoA: lysocardiolipin acyltransferase-1, an endoplasmic reticulum MLCL AT, remained unaltered in SHHF rats. The results provide mechanisms whereby both cardiolipin biosynthesis and remodeling are altered during HF. Increases in CDS-1, PGPS, and MLCL AT suggest compensatory mechanisms during the development of HF. Human and SD data imply that similar trends may occur in human HF, but not during nonpathological aging, consistent with previous cardiolipin studies. 相似文献
9.
Distinguishing between cryptic species is a perennial problem for biologists. Bombus ruderatus and Bombus hortorum are two species of bumblebee, which can be indistinguishable from their morphology. The former species is in decline, whereas the latter is ubiquitous. In the UK, isolated records of B. ruderatus occur amongst many for B. hortorum. For ecological studies of B. ruderatus to be feasible, the two species need to be reliably distinguishable. We present a diagnostic tool for quick and reliable identification of problematic individuals based on a restriction enzyme digest of the cytochrome b region of mitochondrial DNA. 相似文献
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