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231.
Carlos M.G. Azevedo Carlos M.M. Afonso Diana Sousa Raquel T. Lima M. Helena Vasconcelos Madalena Pedro João Barbosa Arlene G. Corrêa Salette Reis Madalena M.M. Pinto 《Bioorganic & medicinal chemistry》2013,21(11):2941-2959
A promising antitumor xanthone derivative was optimized following a multidimensional approach that involved the synthesis of 17 analogues, the study of their lipophilicity and solubility, and the evaluation of their growth inhibitory activity on four human tumor cell lines. A new synthetic route for the hit xanthone derivative was also developed and applied for the synthesis of its analogues. Among the used cell lines, the HL-60 showed to be in general more sensitive to the compounds tested, with the most potent compound having a GI50 of 5.1 μM, lower than the hit compound. Lipophilicity was evaluated by the partition coefficient (Kp) of a solute between buffer and two membrane models, namely liposomes and micelles. The compounds showed a log Kp between 3 and 5 and the two membrane models showed a good correlation (r2 = 0.916) between each other. Studies concerning relationship between solubility and structure were developed for the hit compound and 5 of its analogues. 相似文献
232.
Lucas C. Pantaleão Gabriela F.R. Teodoro Francisco L. Torres-Leal Daiana Vianna Tatyana D. de Paula Emídio M. de Matos-Neto Michele C.C. Trindade Marcelo M. Rogero Carlos R. Bueno Julio Tirapegui 《The Journal of nutritional biochemistry》2013,24(7):1340-1348
The positive regulation of insulin pathway in skeletal muscle results in increased activity of the mammalian target of rapamycin (mTOR), a positive effector of mRNA translation rate and protein synthesis. Studies that assess the activity of this protein in response to chronic high-fat diet (HFD) are scarce and controversial, and to date, there are no studies evaluating the mTOR pathway in infants exposed to gestational and postgestational HFD. This study investigated the effect of maternal HFD on skeletal muscle morphology and on phosphorylation of proteins that comprise the intracellular mTOR signaling pathway in soleus muscle of offspring at weaning. For this purpose, 10 days prior to conception, 39 female Wistar rats were randomly assigned to either control diet (CTL) or HFD. Later, rats were distributed into four groups according to gestational and postpregnancy diet: CTL/CTL (n=10), CTL/HF (n=11), HF/HF (n=10) and HF/CTL (n=8). After 21 days of lactation, pups were killed, and blood samples and soleus and gastrocnemius skeletal muscle were collected for analysis. We observed an influence of maternal postgestational diet, rather than gestational diet, in promoting an obese phenotype, characterized by body fat accumulation, insulin resistance and high serum leptin, glucose, triglycerides and cholesterol levels (P<.05). We have also detected alterations on skeletal muscle morphology — with reduced myofiber density — and impairment on S6 kinase 1 and 4E binding protein-1 phosphorylation (P<.05). These results emphasize the importance of maternal diet during lactation on muscle morphology and on physiological adaptations of infant rats. 相似文献
233.
Sandro M. Hirabara Alessandra Folador Jarlei Fiamoncini Rafael H. Lambertucci Carlos F. Rodrigues Marlene S. Rocha Julia Aikawa Ricardo K. Yamazaki Amanda R. Martins Alice C. Rodrigues Angelo R. Carpinelli Tania C. Pithon-Curi Luiz C. Fernandes Renata Gorjão Rui Curi 《The Journal of nutritional biochemistry》2013,24(6):1136-1145
We investigated the effect of fish oil supplementation for two consecutive generations on insulin sensitivity in rats. After the nursing period (21 days), female rats from the same prole were divided into two groups: (a) control group and (b) fish oil group. Female rats were supplemented with water (control) or fish oil at 1 g/kg body weight as a single bolus for 3 months. After this period, female rats were mated with male Wistar rats fed on a balanced chow diet (not supplemented). Female rats continued to receive supplementation throughout gestation and lactation periods. The same treatment was performed for the next two generations (G1 and G2). At 75 days of age, male offspring from G1 and G2 generations from both groups were used in the experiments. G1 rats did not present any difference with control rats. However, G2 rats presented reduction in glycemia and lipidemia and improvement in in vivo insulin sensitivity (model assessment of insulin resistance, insulin tolerance test) as well as in vitro insulin sensitivity in soleus muscle (glucose uptake and metabolism). This effect was associated with increased insulin-stimulated p38 MAP kinase phosphorylation and lower n-6/n-3 fatty acid ratio, but not with activation of proteins from insulin signaling (IR, IRS-1 and Akt). Global DNA methylation was decreased in liver but not in soleus muscle. These results suggest that long-term fish oil supplementation improves insulin sensitivity in association with increased insulin-stimulated p38 activation and decreased n-6:n-3 ratio in skeletal muscle and decreased global DNA methylation in liver. 相似文献
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236.
N. C. C. Oliveira P. S. N. Lopes L. M. Ribeiro M. O. Mercandante-Simões L. A. A. Oliveira F. O. Silvério 《Trees - Structure and Function》2013,27(6):1633-1645
Butia capitata is a palm tree endemic to the Cerrado biome of Brazil and has significant potential for ornamental and food uses. In this work, we characterized the structures of the seeds and seedlings of this species to identify anatomical aspects related to its pronounced dormancy and determine the processes involved in reserve mobilization. Intact seeds, and seeds from which the operculum had been removed, were allowed to germinate and their morphology, physiology, anatomy, and histochemistry, together with those of the seedlings, were followed for 30 days. The seed coat was found to be rich in phenolic compounds and not lignified. The endosperm contains abundant protein and lipidic reserves, and the embryo has additional starch reserves. Germination occurred only in seeds with their opercula removed and involved the elongation of the cotyledon cells and meristematic activity in the “M zone” located between the embryonic axis and the proximal extremity of the embryo. The mobilization of embryonic reserves initiates during the first phase of imbibition, while the mobilization of endosperm reserves represents a post-germination event associated with the formation of a secretory epidermis and aerenchyma and the vascularization of the haustorium. Seeds with intact opercula did not germinate, but demonstrated embryonic reserve mobilization and cell elongation, indicating that dormancy in B. capitata is related to the incapacity of the embryo to dislocate the operculum. 相似文献
237.
João Pedro Tereso Pablo Ramil-Rego Teresa Pires De Carvalho Rubim Almeida-da-Silva Filipe Costa Vaz 《Vegetation History and Archaeobotany》2013,22(6):479-492
Archaeobotanical material was recovered in two contiguous compartments of a compound in Monte Mozinho (Penafiel, northern Portugal). These areas comprise storage facilities from three different typologies—dolium, pits and above-ground quadrangular structures in the corner of the compartments. Few carpological materials were found inside the storage structures and all these are cereals which were most likely stored as clean grain. Recovered grains are probably remnants of the last stored crops prior to abandonment of the area. A radiocarbon date obtained on grains of rye positions this event at a time within the 3rd century and the beginning of the 4th century a.d. Outside the structures from compartment 2, abundant crop processing by-products, mostly weeds and chaff, were recovered. Since traditional agricultural communities tend not to waste such organic material, it is likely that it was kept in the area to be used as fodder. Data is ambiguous regarding the possible existence of fodder crops mixed with these by-products. Overall, there is a predominance of millets (Panicum miliaceum and Setaria italica) and rye (Secale cereale), but naked wheat (Triticum aestivum) is also a relevant crop. The presence of oat (Avena) is significant but it is difficult to interpret due to its exclusive presence alongside weeds and chaff. Grape pips (Vitis vinifera) were also found, but these are rare. The Late Roman carpological material from Monte Mozinho is of great relevance on a regional level. It documents and dates the presence of rye and testifies to a multifunctional system in which plant husbandry and animal breeding were intertwined. 相似文献
238.
Miguel Brandão Llorenç Milà i Canals 《The International Journal of Life Cycle Assessment》2013,18(6):1243-1252
Purpose
The inclusion of land-use activities in life cycle assessment (LCA) has been subject to much debate in the LCA community. Despite the recent methodological developments in this area, the impacts of land occupation and transformation on its long-term ability to produce biomass (referred to here as biotic production potential [BPP]) — an important endpoint for the Area of Protection (AoP) Natural Resources — have been largely excluded from LCAs partly due to the lack of life cycle impact assessment methods.Materials and methods
Several possible methods/indicators for BPP associated with biomass, carbon balance, soil erosion, salinisation, energy, soil biota and soil organic matter (SOM) were evaluated. The latter indicator was considered the most appropriate for LCA, and characterisation factors for eight land use types at the climate region level were developed.Results and discussion
Most of the indicators assessed address land-use impacts satisfactorily for land uses that include biotic production of some kind (agriculture or silviculture). However, some fail to address potentially important land use impacts from other life cycle stages, such as those arising from transport. It is shown that the change in soil organic carbon (SOC) can be used as an indicator for impacts on BPP, because SOC relates to a range of soil properties responsible for soil resilience and fertility.Conclusions
The characterisation factors developed suggest that the proposed approach to characterize land use impacts on BBP, despite its limitations, is both possible and robust. The availability of land-use-specific and biogeographically differentiated data on SOC makes BPP impact assessments operational. The characterisation factors provided allow for the assessment of land-use impacts on BPP, regardless of where they occur thus enabling more complete LCAs of products and services. Existing databases on every country’s terrestrial carbon stocks and land use enable the operability of this method. Furthermore, BPP impacts will be better assessed by this approach as increasingly spatially specific data are available for all geographical regions of the world at a large scale. The characterisation factors developed are applied to the case studies (Part D of this special issue), which show the practical issues related to their implementation. 相似文献239.
Filipe S. Dias Miguel N. Bugalho J. Orestes Cerdeira M. João Martins 《Biodiversity and Conservation》2013,22(1):93-112
Over the last four decades the world has been losing biodiversity at an alarming rate despite the increasing number of protected areas (PAs). Certified forest management may complement the role of PAs in protecting biodiversity. Forest certification aims to promote sustainable forest management and to maintain or enhance the conservation value of certified forests. The area of forest under certified forest management has grown quickly over the past decade. Forest Stewardship Council (FSC) certification, for example, currently covers 148 million hectares, i.e., 3.7 % of the world’s forests. In spite of such increase there is, however, a dearth of information on how forest certification is related to biodiversity. In this study we assessed if FSC certification is being applied in high biodiversity areas in cork oak savannas in Portugal by comparing biodiversity values of certified and non-certified areas for birds, reptiles and amphibians. We calculated the relative species richness and irreplaceability value for each group of species in certified and non-certified areas and compared them using randomization tests. The biodiversity value of certified areas was not significantly greater than that of non-certified areas. Since FSC certification is expanding quickly in cork oak savannas it is important to consider the biodiversity value of these areas during this process. Prioritizing areas of high biodiversity value would enhance the conservation value of forest certification and facilitate integrating certification with other conservation initiatives. 相似文献
240.
Walter Santos de Araújo Claudia Scareli-Santos Frederico Augusto Guimarães Guilherme Pablo Cuevas-Reyes 《Biodiversity and Conservation》2013,22(4):1083-1094
Plant species diversity maintains the stability of ecosystems and the diversity of consumer species such as insect herbivores. Considering that gall-inducing insects are highly specialized on their host plants and dependent on the occurrence, abundance and distribution of plants, we evaluated the diversity patterns of gall-inducing insect along Brazilian Neotropical savannas and the potential role of plant species richness, vegetation structure and super-host presence on determining these patterns. We found 1,882 individual plants that belonged to 64 different host plant species grouped in 31 families, associated to 112 galling insect species. The galling richness was positively influenced by plant species richness and the presence of the super-host genus Qualea (Vochysiaceae). Plant species richness explained 48 % of the galling richness and areas with presence of super-hosts had more than twice of galling species than areas where they were absent. On the other hand, we found no evidence that larger plants hosted more species of galling insects. We observed that for the diversity of galling insects in the Brazilian Cerrado, vegetation structure explained almost the same portion as plant richness, because structural variables did not have an effect on residuals of galling richness and plant richness regression. Our findings suggests that plant richness has a more important role on the mitigation of natural enemies and adaptive radiation of galling species, while structural aspects of the vegetation does not seem to have that effect. Furthermore, we show that the super-host taxa provide an increment in local galling richness because they present a great diversity of local number of gall morphospecies (i.e. alpha diversity) and the high turnover of morphospecies among different localities (i.e. beta diversity). Therefore we argue that the quality of resources (richness and super host presence) appears to be a most important factor for the diversity of galling insects in Neotropical systems, than the amount of resources. 相似文献