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Olatz Arteaga Miren Revuelta Leyre Urigüen Antonia álvarez Haizea Montalvo Enrique Hilario 《PloS one》2015,10(11)
Despite advances in neonatal care, hypoxic-ischemic brain injury is still a serious clinical problem, which is responsible for many cases of perinatal mortality, cerebral palsy, motor impairment and cognitive deficits. Resveratrol, a natural polyphenol with important anti-oxidant and anti-inflammatory properties, is present in grapevines, peanuts and pomegranates. The aim of the present work was to evaluate the possible neuroprotective effect of resveratrol when administered before or immediately after a hypoxic-ischemic brain event in neonatal rats by analyzing brain damage, the mitochondrial status and long-term cognitive impairment. Our results indicate that pretreatment with resveratrol protects against brain damage, reducing infarct volume, preserving myelination and minimizing the astroglial reactive response. Moreover its neuroprotective effect was found to be long lasting, as behavioral outcomes were significantly improved at adulthood. We speculate that one of the mechanisms for this neuroprotection may be related to the maintenance of the mitochondrial inner membrane integrity and potential, and to the reduction of reactive oxygen species. Curiously, none of these protective features was observed when resveratrol was administered immediately after hypoxia-ischemia. 相似文献
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Excess formaldehyde was extracted from embalmed animal cadavers by vascular perfusion or combined perfusion and percolation with 20% ethanol. The perfusion was undertaken through a carotid artery and the percolation through the serous body cavities for 1-2 h. Nineteen goats were perfused once and one goat and three cows were perfused and percolated twice a day for 3 days. The extracted cadavers were stored in 20% ethanol or in a freezer at -20 degrees C. The mean value of the atmospheric concentration of formaldehyde after extraction was 0.27 +/- 0.05 mg/m3 for goats and 0.39 +/- 0.12 mg/m3 for cows. 相似文献
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Molecular Genetics and Genomics - 相似文献
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Sander A.B. Weelink Wim van Doesburg Flávia Talarico Saia W. Irene C. Rijpstra Wilfred F.M. Röling Hauke Smidt & Alfons J.M. Stams 《FEMS microbiology ecology》2009,70(3):243-253
A bacterium (strain G5G6) that grows anaerobically with toluene was isolated from a polluted aquifer (Banisveld, the Netherlands). The bacterium uses Fe(III), Mn(IV) and nitrate as terminal electron acceptors for growth on aromatic compounds. The bacterium does not grow on sugars, lactate or acetate. Phylogenetic analysis of the 16S rRNA gene sequence indicated that strain G5G6 belonged to the Betaproteobacteria . Its closest, but only distantly related, cultured relative is Sterolibacterium denitrificans Chol-1ST (94.6% similarity of the 16S rRNA genes), a cholesterol-oxidizing, denitrifying bacterium. Strain G5G6 possesses the benzylsuccinate synthase A ( bssA ) gene encoding the α-subunit of Bss, which catalyzes the first step in anaerobic toluene degradation. The deduced BssA amino acid sequence is closely related to those of Azoarcus and Thauera species, which also belong to the Betaproteobacteria . Strain G5G6 is the first toluene-degrading, iron-reducing bacterium that does not belong to the Geobacteraceae within the Deltaproteobacteria . Based on phylogenetic and physiological comparison, strain G5G6 could not be assigned to a described species. Therefore, strain G5G6 (DSMZ 19032T =JCM 14632T ) is a novel taxon of the Betaproteobacteria . We propose the name Georgfuchsia toluolica gen. nov., sp. nov. 相似文献
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嗅觉受体(olfactory receptor)不仅表达在鼻腔中,还广泛表达在全身其他部位,起着重要的生理作用.本文综述了非嗅觉组织和细胞中表达的嗅觉受体及其功能,这些嗅觉受体通过调控细胞周围的内源性化学物质,维持正常的生理功能,并且能在选定的外源性配体刺激下,表现出特定的功能.在医药领域,大约有40%上市药物的作用靶点都来自于G蛋白偶联受体(GPCR)家族,而嗅觉受体是GPCR中最大的基因家族,鉴于其表现出的重要作用,我们推测这些嗅觉受体可能成为未来重要的药物靶标.本文对非嗅觉组织和细胞中嗅觉受体功能的综述,一方面有利于将其作为潜在药物靶点,开发新的药物,另一方面也为中药中挥发性单体的药理作用提供了新的研究思路. 相似文献
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Drahomíra Kenov Lucie oltysov Michal Pravenec Marie-Pierre Moisan W. Theodore Kurtz Vladimír Ken 《Journal of Experimental Animal Science》2000,41(1-2)
The SHR-Lx congenic strain carrying a differential segment of chromosome 8 of BN and PD origin was recently shown to exhibit a significant decrease in blood pressure as compared to the SHR strain. There were two positional candidate genes for blood pressure control mapped to the differential segment: the rat kidney epithelial potassium channel gene (Kcnj1) and brain dopamine receptor 2 gene (Drd2). Bot these genes were separated into SHR.BN-RNO8 congenic substrains. In this communication, we are presenting the assignment of two further putative candidate genes, which might be involved in blood pressure control to the BN/PD differential segment of the SHR-Lx congenic strain. These are: the gene coding for smooth muscle cell specific protein 22 (Sm22) defined by the D8Mcw1 marker and neuronal nicotinic acetylcholine receptor gene cluster, defined by the D8Bord1 marker. Moreover, the glutamate receptor gene Grik4 which also maps to the differential segment of the SHR-Lx should be taken into account. The genetic separation of all these putative candidate genes of blood pressure control is being performed by recombinations and subsequent selection using (SHR×SHR-Lx) intercross population. 相似文献
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