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971.
The Mediterranean diet is associated with a lower incidence of chronic degenerative diseases and higher life expectancy. These health benefits have been partially attributed to the dietary consumption of extra virgin olive oil (EVOO) by Mediterranean populations, and more specifically the phenolic compounds naturally present in EVOO. Studies involving humans and animals (in vivo and in vitro) have demonstrated that olive oil phenolic compounds have potentially beneficial biological effects resulting from their antimicrobial, antioxidant and anti-inflammatory activities. This paper summarizes current knowledge on the biological activities of specific olive oil phenolic compounds together with information on their concentration in EVOO, bioavailability and stability over time. 相似文献
972.
Lucas N. Paolucci Ricardo R. C. Solar Tathiana G. Sobrinho Carlos F. Sperber José H. Schoereder 《Biodiversity and Conservation》2012,21(12):3095-3105
Remnant isolation following fragmentation is considered to be one of the main drivers of ecological decline in modified landscapes. Thereby, connecting remnants using ecological corridors has been increasingly suggested as being important for conservation. Our objectives were to test isolation effects on extinction, colonization and turnover rates of a litter-dwelling ant assemblage, and to evaluate effectiveness of ecological corridors to mitigate habitat fragmentation consequences. We used a mesocosm manipulative design, with three different isolation treatments: far, near and near connected by a corridor, sampled fortnightly for 60?days. Fragmentation caused an ongoing decrease in ant species richness, probably due to a negative balance between extinction and colonization. Extinction was steady with time, while colonization decreased over the same period. This outcome highlights the key role that colonization plays in the persistence of populations of litter-dwelling ants. Turnover rates increased with time in the treatment with a corridor, but remained steady in the other treatments. We conclude that corridors are important for not only immigration to remnants, but also emigration, acting as a two way traffic route. Thus, it may be an important “leakage” point for threatened species, with implications for their conservation status. 相似文献
973.
Santana AB Lucas SD Gonçalves LM Correia HF Cardote TA Guedes RC Iley J Moreira R 《Bioorganic & medicinal chemistry letters》2012,22(12):3993-3997
The synthesis, inhibitory activity and mode of action of oxazolidine-2,4-diones against porcine pancreatic elastase, here used as a model for human neutrophil elastase, are reported. The nature of N-substitution at the oxazolidine-2,4-dione scaffold has large effect on the inhibitory potency against elastase. N-Acyl and N-sulfonyloxazolidine-2,4-diones emerged as potent pseudo-irreversible inhibitors, displaying high second-order rate constants for PPE inactivation. The title compounds were also shown to be potent inhibitors of human neutrophil elastase (HNE) and proteinase-3, and weak inhibitors of human cathepsin G. The results herein presented show that the oxazolidine-2,4-diones represent a new promising class of serine protease inhibitors. 相似文献
974.
Davies DJ Crowe M Lucas N Quinn J Miller DD Pritchard S Grose D Bettini E Calcinaghi N Virginio C Abberley L Goldsmith P Michel AD Chessell IP Kew JN Miller ND Gunthorpe MJ 《Bioorganic & medicinal chemistry letters》2012,22(7):2620-2623
A series of novel benzimidazoles are discussed as NR2B-selective N-methyl-d-aspartate (NMDA) receptor antagonists. High throughput screening (HTS) efforts identified a number of potent and selective NR2B antagonists such as 1. Exploration of the substituents around the core of this template identified a number of compounds with high potency for NR2B (pIC(50) >7) and good selectivity against the NR2A subunit (pIC(50) <4.3) as defined by FLIPR-Ca(2+) and radioligand binding studies. These agents offer potential for the development of therapeutics for a range of nervous system disorders including chronic pain, neurodegeneration, migraine and major depression. 相似文献
975.
Lucas Leite AC Rosenblatt A da Silva Calixto M da Silva CM Santos N 《Mutation research》2012,747(1):93-97
OBJECTIVE: To investigate whether formocresol, in Buckley's original formulation, used for pulp therapy of deciduous teeth, can have a genotoxic effect. Genotoxicity was tested in lymphocyte cultures from the peripheral blood of children aged 5-10y, in Recife, Pernambuco, Brazil. This was a case-control study. The sample comprised 40 children who had primary teeth with non-vital pulps. Two venous blood samples (6-8ml) were collected from each child, the first prior to pulp therapy (control group) and the second 24h after pulp therapy (experimental group). Lymphocyte cultures were grown in 78% RPMI 1640 medium, 20% fetal bovine serum, 2% phytohemagglutinin. The lymphocytes were assessed for chromosomal aberrations; each sample involved analysis of 100 metaphases. There was a statistically significant difference between the control and treated groups for the isochromatid gap (p<0.001), chromatid break (p<0.009), isochromatid break (p<0.046), other chromosomal alterations (p<0.001), and for total aberrations. In view of these results, caution in the use of formocresol in pediatric dentistry is recommended. 相似文献
976.
Panter S Chu PG Ludlow E Garrett R Kalla R Jahufer MZ de Lucas Arbiza A Rochfort S Mouradov A Smith KF Spangenberg G 《Transgenic research》2012,21(3):619-632
Viral diseases, such as Alfalfa mosaic virus (AMV), cause significant reductions in the productivity and vegetative persistence of white clover plants in the field. Transgenic white clover plants ectopically expressing the viral coat protein gene encoded by the sub-genomic RNA4 of AMV were generated. Lines carrying a single copy of the transgene were analysed at the molecular, biochemical and phenotypic level under glasshouse and field conditions. Field resistance to AMV infection, as well as mitotic and meiotic stability of the transgene, were confirmed by phenotypic evaluation of the transgenic plants at two sites within Australia. The T(0) and T(1) generations of transgenic plants showed immunity to infection by AMV under glasshouse and field conditions, while the T(4) generation in an agronomically elite 'Grasslands Sustain' genetic background, showed a very high level of resistance to AMV in the field. An extensive biochemical study of the T(4) generation of transgenic plants, aiming to evaluate the level and composition of natural toxicants and key nutritional parameters, showed that the composition of the transgenic plants was within the range of variation seen in non-transgenic populations. 相似文献
977.
Bigot L Shaik HA Bozzolan F Party V Lucas P Debernard S Siaussat D 《Insect biochemistry and molecular biology》2012,42(1):22-31
Physiological and behavioral plasticity allows animals to adapt to changes in external (environmental) and internal (physiological) factors. In insects, the physiological state modulates adult behavior in response to different odorant stimuli. Hormones have the potential to play a major role in the plasticity of the olfactory responses. To explore if peripheral olfactory processing could be regulated by steroid hormones, we characterized the molecular, electrophysiological, and behavioral response to changes in endogenous hormone levels in adult male Spodoptera littoralis. The expression of the receptor complex (EcR/USP) was localized by in situ hybridization in the olfactory sensilla of antennae. Injections of 20-hydroxyecdysone (20E) induced an ecdysteroid signaling pathway in antennae and increased expression of the nuclear receptors EcR, USP and E75. Diacylglycerol kinase (DGK) and CaM expression were also up-regulated by 20E. Taken together, these molecular, electrophysiological, and behavioral results suggest a hormonal regulation of the peripheral olfactory processing in S. littoralis. 相似文献
978.
Haber M Platt DE Ashrafian Bonab M Youhanna SC Soria-Hernanz DF Martínez-Cruz B Douaihy B Ghassibe-Sabbagh M Rafatpanah H Ghanbari M Whale J Balanovsky O Wells RS Comas D Tyler-Smith C Zalloua PA;Genographic Consortium 《PloS one》2012,7(3):e34288
Afghanistan has held a strategic position throughout history. It has been inhabited since the Paleolithic and later became a crossroad for expanding civilizations and empires. Afghanistan's location, history, and diverse ethnic groups present a unique opportunity to explore how nations and ethnic groups emerged, and how major cultural evolutions and technological developments in human history have influenced modern population structures. In this study we have analyzed, for the first time, the four major ethnic groups in present-day Afghanistan: Hazara, Pashtun, Tajik, and Uzbek, using 52 binary markers and 19 short tandem repeats on the non-recombinant segment of the Y-chromosome. A total of 204 Afghan samples were investigated along with more than 8,500 samples from surrounding populations important to Afghanistan's history through migrations and conquests, including Iranians, Greeks, Indians, Middle Easterners, East Europeans, and East Asians. Our results suggest that all current Afghans largely share a heritage derived from a common unstructured ancestral population that could have emerged during the Neolithic revolution and the formation of the first farming communities. Our results also indicate that inter-Afghan differentiation started during the Bronze Age, probably driven by the formation of the first civilizations in the region. Later migrations and invasions into the region have been assimilated differentially among the ethnic groups, increasing inter-population genetic differences, and giving the Afghans a unique genetic diversity in Central Asia. 相似文献
979.
Ghansah A Rockett KA Clark TG Wilson MD Koram KA Oduro AR Amenga-Etego L Anyorigiya T Hodgson A Milligan P Rogers WO Kwiatkowski DP 《PloS one》2012,7(4):e34565
Background
Haemoglobin S (HbS) and C (HbC) are variants of the HBB gene which both protect against malaria. It is not clear, however, how these two alleles have evolved in the West African countries where they co-exist at high frequencies. Here we use haplotypic signatures of selection to investigate the evolutionary history of the malaria-protective alleles HbS and HbC in the Kassena-Nankana District (KND) of Ghana.Methodology/Principal Findings
The haplotypic structure of HbS and HbC alleles was investigated, by genotyping 56 SNPs around the HBB locus. We found that, in the KND population, both alleles reside on extended haplotypes (approximately 1.5 Mb for HbS and 650 Kb for HbC) that are significantly less diverse than those of the ancestral HbA allele. The extended haplotypes span a recombination hotspot that is known to exist in this region of the genomeSignificance
Our findings show strong support for recent positive selection of both the HbS and HbC alleles and provide insights into how these two alleles have both evolved in the population of northern Ghana. 相似文献980.
Cartier AE Ubhi K Spencer B Vazquez-Roque RA Kosberg KA Fourgeaud L Kanayson P Patrick C Rockenstein E Patrick GN Masliah E 《PloS one》2012,7(4):e34713
Parkinson's disease (PD) is a progressive neurodegenerative disorder caused by genetic and environmental factors. Abnormal accumulation and aggregation of alpha-synuclein (a-syn) within neurons, and mutations in the a-syn and UCH-L1 genes have been shown to play a role in the pathogenesis of PD. In light of recent reports suggesting an interaction between a-synuclein and UCH-L1, we investigated the effects of UCH-L1 inhibition on a-syn distribution and expression levels in primary neurons and hippocampal tissues derived from non transgenic (non tg) and a-syn over expressing tg mice. We show that suppression of UCH-L1 activity increased a-syn levels in control, non tg neurons, and resulted in a concomitant accumulation of presynaptic a-syn in these neurons. In contrast, blocking UCH-L1 activity in a-syn over expressing neurons decreased a-syn levels, and enhanced its synaptic clearance. In vitro studies verified the LDN-induced inhibition of UCH-L1 had minimal effect on LC3 (a marker of autophagy) in control cells, in cells over expressing a-syn UCH-L1 inhibition resulted in increased LC3 activity. These findings suggest a possible differential role of UCH-L1 function under normal and pathological conditions. Furthermore, in the context of a-syn-induced pathology, modulation of UCH-L1 activity could serve as a therapeutic tool to enhance the autophagy pathway and induce clearance of the observed accumulated/aggregated a-syn species in the PD brain. 相似文献