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Naproxen and cromolyn were investigated as new inhibitors of glycogen synthase kinase‐3β (GSK‐3β) in an attempt to explain their hypoglycemic properties. Study included simulated docking experiments, in vitro enzyme inhibition assay, and in vivo validations. Both drugs not only were optimally fitted within a GSK‐3β binding pocket via several attractive interactions with key amino acids but also exhibited potent in vitro enzymatic inhibitory activities of IC50 1.5 and 2.0 µM for naproxen and cromolyn, respectively. In vivo experiments illustrated that both drugs significantly reduced serum glucose and increased hepatic glycogen‐ and serum insulin levels in normal and type II diabetic Balb/c mice models. In obese animal model, both drugs exhibited significant reduction in mice weights, serum glucose, and resistin levels along with significant elevation in serum insulin, C‐peptide, and adiponectin values. It can be concluded that naproxen and cromolyn are novel GSK‐3β inhibitors and can help in management of diabetes and obesity. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:425–436, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21503  相似文献   
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Proteins in the soluble and insoluble fractions, extracted frommature castor bean cv. Hale seed cotyledons, differ quantitativelyand qualitatively from their counterparts extracted from theendosperm. The soluble fraction contains no glycoproteins, andthe lectins RCA1 and ricin D are absent. While the insolubleproteins are electrophoretically and immunologically similarto those in the endosperm, they do not form the 100 kD subunitdimers which characterize some of the endosperm insoluble crystalloidproteins. Rapid rates of deposition of all of the soluble andinsoluble proteins present in the mature seed cotyledons commences30–35 d after pollination (DAP) and continues until 45DAP. These proteins are mobilized rapidly beginning 1–2d after seed imbibition and this coincides with an increasein specific activity, in the cotyledons, of two aminopeptidasesand a carboxypeptidase. The soluble and insoluble proteins inthe cotyledons of the mature seed probably function as storageproteins and support the growth of the germinated seed priorto the mobilization of the major protein storage reserves ofthe endosperm. Key words: Ricinus communis, Castor bean, Hale cultivar, Cotyledon, Storage protein, Seed development, Seed germination  相似文献   
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Soil amendments containing carbonized materials increase the soil carbon reservoir, influence plant productivity, and, ultimately, help to clean the environment. There is data on the effect of such additions on soil physicochemical properties or plant growth, but few studies have focused on how these carbonized materials are distributed by termite species in the soil ecosystem. It is the first comprehensive study of the transportation of biochar (BC) by termite species under tropical environmental conditions in Pakistan. The present study was carried out to test the hypothesis that if termite species I) were involved in the distribution of biochar particles II) if yes, then how far these particles were transported during the study period (10 days) and III) check their preference between the enriched BC (EBC) and non-enriched BC. BC was enriched with the cattle slurry after its pyrolysis in the study. The results showed that EBC particles were significantly more widely distributed than non-enriched BC particles, but both types of BC were transported more than 4 cm (ring 4) within 10 days (at the end of the experiment). The current study also revealed that EBC was easily attached to the setae, cuticle, and legs of termites, implying that it could potentially be transported over a greater distance. Furthermore, transportation of EBC over larger distances indicated a potential preference of termite species between the EBC and BC particles. During the study, however, the preference among the termite species was also observed. Under the prevailing study conditions, the Coptotermes heimi and Heteroterme indicola species transported the EBC further than Microtermes obesi and Odontotermes obesus. These findings revealed that transportation preferences were observed among the four termite species. In conclusion, the current study found that termites were involved in the distribution of BC particles, with a preference for EBC and that these have the potential to transport BC particles more than 4 cm within 10 days. Furthermore, two species Coptotermes heimi and Heteroterme indicola may be more suitable candidates for EBC transpiration in Pakistani soils. It was necessary to conduct additional research into the effect of temperature on the transportation process.  相似文献   
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The leaf temperature of six annual and six perennial plant species was monitored during spring and summer on a sand dune ecosystem in the delta Mediterranean coast of Egypt. During winter, leaves of all tested perennial species attained temperatures higher than the air temperature at night and shortly after sunrise, with maximum leaf–air temperature differences reaching up to 8°C. The lowest differences were less than 1°C. Around noon, the leaves of several species attained temperatures lower than that of the air whereas others showed higher temperatures. The opposite was true during summer, when leaf temperatures were lower than air temperature. The maximum leaf–air temperature differences occurred after midnight towards sunrise and reached up to 10°C. The lowest differences were found around noon and were of less than 5°C. The annual plant species have more pronounced variations than perennials in their leaf temperatures during the night and for most of the day. The leaves were heated or cooled a few degrees above or below the air temperature. The results are discussed in relation to the morphological characters of the leaves. The variation in leaf temperature at different times of the day was significantly related to leaf morphology, specific leaf area, thickness, volume, leaf area index and the surrounding environment.  相似文献   
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Cell-penetrating peptides (CPPs) are membrane permeable vectors recognized for their intrinsic ability to gain access to the cell interior. The hydrophobic counter-anion, pyrenebutyrate, enhances cellular uptake of oligoarginine CPPs. To elucidate CPP uptake mechanisms, the effect of pyrenebutyrate on well-recognized CPPs with varying hydrophobicity and arginine content is investigated. The cellular CPP uptake and CPP-mediated oligonucleotide delivery is analyzed by fluorescence activated cell sorting, confocal microscopy, and a cell-based splice-switching assay. The splice-switching oligonucleotide is a mixmer of 2′-O-methyl RNA and locked nucleic acids delivered as a non-covalent complex with 10-fold molar CPP excess. CPP-induced membrane perturbation on large unilamellar vesicles is investigated in calcein release experiments. We observed that pyrenebutyrate facilitates cellular uptake and translocation of oligonucleotide mediated by oligoarginine nonamer while limited effect of pyrenebutyrate on more hydrophobic CPPs was observed. By combining the different experimental results we conclude that the pathway for cellular uptake of oligoarginine is dominated by direct membrane translocation, whereas the pathway for oligoarginine-mediated oligonucleotide translocation is dominated by endocytosis. Both mechanisms are promoted by pyrenebutyrate and we suggest that pyrenebutyrate has different sites of action for the two uptake and translocation mechanisms.  相似文献   
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