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排序方式: 共有185条查询结果,搜索用时 468 毫秒
91.
Juan Gambini Raúl López-Grueso Gloria Olaso-González Marta Inglés Khira Abdelazid Marya El Alami Vicent Bonet-Costa Consuelo Borrás José Viña 《Revista espa?ola de geriatría y gerontología》2013
Resveratrol is a natural polyphenol which can be found in many plants and fruits, such as peanuts, mulberries, blueberries and, above all, in grapes and red wine. Its synthesis is regulated by the presence of stressful factors, such as fungal contamination and ultra-violet radiation. In plants, it plays a role as a phytoalexin, showing a capacity to inhibit the development of certain infections. Plant extracts which contain resveratrol have been employed by traditional medicine for more than 2000 years. Resveratrol was first isolated, and its properties were initially studied with scientific methods, thirty years ago. Its in vitro properties have been extensively studied and demonstrated. It is worth highlighting its activity as an anti-cancer agent, platelet anti-aggregation agent, anti-inflammatory, antiallergenic, etc. The activity of its in vivo properties are not so clear. There are many studies that report benefits on the cardiovascular system, illnesses such as diabetes, and in longevity. However, other authors did not find any agreement between in vitro and in vivo studies. This discrepancy is due to the bioavailability of resveratrol. After an oral dose, it has been demonstrated that the absorption is very high, but the metabolic pathways leave just a little free resveratrol in blood, therefore the bioavailability in the target tissues is very low and the concentrations used in in vitro studies are not found in these tissues. Thus, resveratrol is a very active molecule for maintaining health, but due to the low bioavailability not all the in vitro effects can be translated to in vivo. This opens a new potential approach, seeking derivatives of resveratrol that can be measured in the desired tissues 相似文献
92.
93.
Martín-González L Castro R Pereira MA Alves MM Font X Vicent T 《Bioresource technology》2011,102(7):4734-4741
Working at thermophilic conditions instead of mesophilic, and also the addition of a co-substrate, are both the ways to intend to improve the anaerobic digestion of the source-collected organic fraction of municipal solid wastes (SC-OFMSW). Addition of sewage treatment plant fat, oil and grease wastes (STP-FOGW), that are nowadays sent to landfill, would represent an opportunity to recover a wasted methane potential and, moreover, improve the whole process. In this study, after a first period feeding only SC-OFMSW, a co-digestion step was performed maintaining thermophilic conditions. During the co-digestion period enhancements in biogas production (52%) and methane yield (36%) were achieved. In addition, monitoring of microbial structure by using PCR-DGGE and cloning techniques showed that bacterial community profiles clustered in two distinct groups, before and after the extended contact with STP-FOGW, being more affected by the STP-FOGW addition than the archaeal one. 相似文献
94.
Hermosa R Botella L Keck E Jiménez JÁ Montero-Barrientos M Arbona V Gómez-Cadenas A Monte E Nicolás C 《Journal of plant physiology》2011,168(11):1295-1302
Using the TrichoEST database, generated in a previous functional genomics project from the beneficial filamentous fungus Trichoderma harzianum, a gene named Thkel1, which codes for a putative kelch-repeat protein, was isolated and characterized. Silencing of this gene in T. harzianum leads to a reduction of glucosidase activity and mycelial growth under abiotic stress conditions. Expression of this gene in Arabidopsis enhances plant tolerance to salt and osmotic stresses, accompanied by an increase in glucosidase activity and a reduction of abscisic acid levels compared to those observed in wild-type plants. Data presented throughout this article suggest the high value of T. harzianum as a source of genes able to facilitate the achievement of producing plants resistant to abiotic stresses without alteration of their phenotype. 相似文献
95.
96.
Alternative polyadenylation diversifies post‐transcriptional regulation by selective RNA–protein interactions 下载免费PDF全文
97.
98.
Bonet-Costa C Vilaseca M Diema C Vujatovic O Vaquero A Omeñaca N Castejón L Bernués J Giralt E Azorín F 《Journal of Proteomics》2012,75(13):4124-4138
Linker histone H1 is a major chromatin component that binds internucleosomal DNA and mediates the folding of nucleosomes into a higher-order structure, namely the 30-nm chromatin fiber. Multiple post-translational modifications (PTMs) of core histones H2A, H2B, H3 and H4 have been identified and their important contribution to the regulation of chromatin structure and function is firmly established. In contrast, little is known about histone H1 modifications and their function. Here we address this question in Drosophila melanogaster, which, in contrast to most eukaryotic species, contains a single histone H1 variant, dH1. For this purpose, we combined bottom-up and top-down mass-spectrometry strategies. Our results indicated that dH1 is extensively modified by phosphorylation, methylation, acetylation and ubiquitination, with most PTMs falling in the N-terminal domain. Interestingly, several dH1 N-terminal modifications have also been reported in specific human and/or mouse H1 variants, suggesting that they have conserved functions. In this regard, we also provide evidence for the contribution of one of such conserved PTMs, dimethylation of K27, to heterochromatin organization during mitosis. Furthermore, our results also identified multiple dH1 isoforms carrying several phosphorylations and/or methylations, illustrating the high structural heterogeneity of dH1. In particular, we identified several non-CDK sites at the N-terminal domain that appear to be hierarchically phosphorylated. This study provides the most comprehensive PTM characterization of any histone H1 variant to date. 相似文献
99.
Trincavelli ML Daniele S Orlandini E Navarro G Casadó V Giacomelli C Nencetti S Nuti E Macchia M Huebner H Gmeiner P Rossello A Lluís C Martini C 《Cellular signalling》2012,24(4):951-960
The structural and functional interaction between D2 dopamine receptor (DR) and A2A adenosine receptor (AR) has suggested these two receptors as a pharmacological target in pathologies associated with dopamine dysfunction, such as Parkinson's disease. In transfected cell lines it has been demonstrated the activation of D2DR induces a significant negative regulation of A2AAR-mediated responses, whereas few data are at now available about the regulation of A2AAR by D2DR agonists at receptor recognition site. In this work we confirmed that in A2AAR/D2DR co-transfected cells, these receptors exist as homo- and hetero-dimers. The classical D2DR agonists were able to negatively modulate both A2AAR affinity and functionality. These effects occurred even if any significant changes in A2AAR/D2DR energy transfer interaction could be detected in BRET experiments.Since the development of new molecules able to target A2A/D2 dimers may represent an attractive tool for innovative pharmacological therapy, we also identified a new small molecule, 3-(3,4-dimethylphenyl)-1-(2-piperidin-1-yl)ethyl)piperidine (compound 1), full agonist of D2DR and modulator of A2A-D2 receptor dimer. This compound was able to negatively modulate A2AAR binding properties and functional responsiveness in a manner comparable to classical D2R agonists. In contrast to classical agonists, compound 1 led to conformational changes in the quaternary structure in D2DR homomers and heteromers and induced A2AAR/D2DR co-internalization. These results suggest that compound 1 exerts a high control of the function of heteromers and could represent a starting point for the development of new drugs targeting A2AAR/D2 DR heteromers. 相似文献
100.
Marcellino D Ferré S Casadó V Cortés A Le Foll B Mazzola C Drago F Saur O Stark H Soriano A Barnes C Goldberg SR Lluis C Fuxe K Franco R 《The Journal of biological chemistry》2008,283(38):26016-26025
The function of dopamine D(3) receptors present in the striatum has remained elusive. In the present study evidence is provided for the existence of dopamine D(1)-D(3) receptor heteromers and for an intramembrane D(1)-D(3) receptor cross-talk in living cells and in the striatum. The formation of D(1)-D(3) receptor heteromers was demonstrated by fluorescence resonance energy transfer and bioluminescence resonance energy transfer techniques in transfected mammalian cells. In membrane preparations from these cells, a synergistic D(1)-D(3) intramembrane receptor-receptor interaction was observed, by which D(3) receptor stimulation enhances D(1) receptor agonist affinity, indicating that the D(1)-D(3) intramembrane receptor-receptor interaction is a biochemical characteristic of the D(1)-D(3) receptor heteromer. The same biochemical characteristic was also observed in membrane preparations from brain striatum, demonstrating the striatal co-localization and heteromerization of D(1) and D(3) receptors. According to the synergistic D(1)-D(3) intramembrane receptor-receptor interaction, experiments in reserpinized mice showed that D(3) receptor stimulation potentiates D(1) receptor-mediated behavioral effects by a different mechanism than D(2) receptor stimulation. The present study shows that a main functional significance of the D(3) receptor is to obtain a stronger dopaminergic response in the striatal neurons that co-express the two receptors. 相似文献