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81.
The aim if this study was to assess the distribution of mercury in water, suspended particulate matter, surface sediments and biota from the Sado estuary, which, for the most part, is classified as a natural reserve, so as to evaluate its environmental quality status in terms of mercury contamination. Besides the diffuse sources of mercury coming into the Sado estuary, there are also additional contributions from the northern industrial zone and from the urban areas within the system. Applying national and international guidelines to different environmental matrices, the results obtained show that the system does not seem to be under environmental risk as far as mercury contamination is concerned. These quality guidelines can be used to rank and prioritise sites of concern. Hence, the area at the northern industrialised area deserves particular attention. The concentration of mercury in sediments of this area (0.54?mg kg?1) simultaneously succeeded the European Union Water Framework Directive (EU-WFD) reference value, the OSPAR Convention Ecotoxicological Assessment Criteria (EACs) and is classified as class 2 in degree of contamination by the National legislation, which implies some legal restrictive rules. Considering the stations close to urbanised areas, one exceeded the OSPAR EACs for dissolved mercury, whilst the other exceeded the EU-WFD reference value for mercury concentrations in sediments. No statistical significant relations were found between mercury concentrations in biota (Ulva sp, Hediste diversicolor, Scrobicularia plana, Cerstoderma edule and Carcinus maenas) and in the abiotic matrices (sediment and water column, including mercury in its dissolved form and associated to suspended particulate matter). This paper provides an overview of the guidelines for Hg proposed for a considerable number of coastal systems of the northern hemisphere and highlights the complex interactions of Hg in the different environmental compartments in low contaminated systems.  相似文献   
82.
The low-grade inflammation has been recognized as the link between adiposity and the risk of chronic metabolic disorders. Thus, increased concentrations of inflammatory markers, such as interleukins and tumor necrosis factor alpha have been found in obese individuals. In turn, diet can positively or negatively influence on the risk of chronic metabolic diseases by modulating the inflammatory status. In this context, orange juice consumption can play a role in modulation of inflammatory markers through bioactive compounds, such as the flavonoids (hesperidin, naringenin). According to this review, orange juice appears to mediate the inflammatory response in plasma level and gene expression, and in postprandial and chronic (≥7 consecutive days) periods. The current findings suggest that orange juice could be a dietary feature for prevention and treatment of chronic diseases, although more studies are necessary to evaluate the physiological and molecular mechanisms involved.  相似文献   
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84.
The objective was to evaluate the intake, digestibility, and ingestive sheep behavior with feeding phytogenic additives derived from plant extracts. Five non-emasculated sheep without defined breed at 28?±?1.81 kg initial body weight and 6 months age were used. Treatments consisted of administering four phytogenic additives from the garlic extracts, coriander seed, oregano, and pods of mesquite, plus a control treatment (without additive). The ration was composed of Tifton 85 hay grass, corn, soybean meal, and mineral salt. As experimental design, we used a 5?×?5 Latin square design (five treatments and five periods). The data were analyzed through the mixed model through the procedure PROC MIXED of software Systems Statistical Analysis version 9.1, with comparation analysis between the treatment without additive (control) with phytogenic additives produced from vegetable extracts of mesquite pod, of coriander seed, the bulb of garlic, and the oregano leaves. There were no significant differences for the nutrient intake and ingestive behavior patterns. However, the additive intake derived from mesquite pods and coriander extracts provided an increase in digestibility. Extracts from garlic, coriander, and mesquite pods can be used as phytogenic additives in feeding sheep.  相似文献   
85.
The Rickettsiales Ehrlichia ruminantium (ER) is the causative agent of heartwater, a fatal tick-borne disease of livestock in sub-Saharan Africa and in the Caribbean, posing strong economical constraints to livestock production. In an attempt to identify the most prominent proteins expressed by this bacterium, especially those encoded by the major antigenic protein 1 (map1) multigene family, a proteome map of ER cultivated in endothelial cells was constructed by using two dimensional gel electrophoresis combined with mass spectrometry. Among the sixty-four spots detected, we could identify only four proteins from the MAP1-family; the other proteins detected were mainly related to energy, amino acid and general metabolism (26%), to protein turnover, chaperones and survival (21%) and to information processes (14%) or classified as hypothetical proteins (23%). Additional studies on MAP1-family protein using immunochemical labeling also revealed that these proteins are differentially expressed along the bacterium life cycle, presenting different structural organization. Interestingly, when infectious elementary bodies (EBs) are released from host cells, MAP1 appears to be organized in SDS and heat-resistant dimers and trimers stabilized by disulfide bridges. Overall, the results presented herein not only reveal the first partial proteome map of ER but provide new insights on the expression ER MAP1-family proteins in host endothelial cells.  相似文献   
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87.
The Serra do Brigadeiro State Park (PESB) is one of the largest fragments of Brazilian Atlantic Rainforest, and it is relevant for native species conservation. However, monocultures settled around the Park resulted in extensive open areas that facilitate the establishment of alien species on the PESB perimeter, which may threaten native species conservation therein, since biological invasion is the second main cause of global biodiversity loss. In this region, there are also farmers planting agroforestry systems (AFS), characterized by tree-based intercropping, which are structurally more similar to the Atlantic Rainforest reminiscent fragments present in the region and may limit local occurrence of potentially invasive exotic weeds for several reasons, such as the high levels of shade provided by trees, the groundcover that result from loss of tree leaves and the increased competition for belowground resources. This study aimed to test whether AFS limit exotic species establishment when compared to monoculture systems. Accordingly, three coffee monocultures and three agroforestry coffee plantations around the PESB were studied. In each of the six study areas, 30 plots of 1 m2 were established between the lines of coffee plantation, where all species present were surveyed. In both treatments, rarefaction curves were constructed to evaluate native and exotic richness, and diversity of these two categories was estimated through Simpson index inverse (1/D). All 13 sampled exotic species were present in monocultures, but only three of them occurred in AFS. Besides, alien diversity in monocultures (\(1/D\) = 2.173 ± 0.011) was significantly higher than in AFS (\(1/D\) = 1.031 ± 0.001). Such changes in alien plant community between land-use show that AFSs limit invasive species establishment. Therefore, when planted around protected areas, AFS may contribute to the control of biological invasions and to biodiversity conservation.  相似文献   
88.
Downy mildew (DM; Hyaloperonospora brassicae) is one of the most serious diseases in radish and responsible for high production losses. The objectives of this study were (1) to identify new sources of DM resistance at the cotyledon stage; (2) to determine the inheritance of the resistance; and (3) to clarify the histological and cellular response involved in DM infection. We screened 200 radish accessions for DM resistance at the cotyledon stage. Radish accessions Rd001, Rd004, Rd048 and Rd150 showed a complete resistance response (hypersensitive reaction), and accession Rd193 exhibited a partial resistance with confined sporulation. The highly susceptible accession Rd197 was then crossed with all resistant genotypes for a genetic analysis. F2 segregation analysis suggested that cotyledon resistance in Rd001, Rd004, Rd048 and Rd150 is conferred by a single dominant gene while resistance in Rd193 is polygenic. Genetic data suggests Rd193 resistance might be conferred by two dominant genes with complementary action, althought further experiments are needed to confirm this hypothesis. To conduct a histological study using light and fluorescence microscopy, we collected cotyledons from three genotypes with either differing levels of resistance (Rd004 and Rd193) and high susceptibility (Rd197) at ten different time points, from 3 h to 7 days post inoculation. Tissue necrosis was responsible for the inhibition and reduction of H. brassicae growth in Rd004 and Rd193 within 24 h of inoculation. For susceptible accession Rd197, the first evidence of necrotic cells appeared 48 h post inoculation. Callose deposition associated with intercellular H. brassicae growth occurred 3 h post inoculation for all genotypes and was the lowest in resistant accession Rd004. Cotyledon resistance to DM identified in radish is of high commercial interest and has the potential to be used in breeding programs.  相似文献   
89.
In previous studies, it has not been reported that protein isolated from chia interferes favorably with antibacterial activity, and reduces cholesterol synthesis. The objective of this study was to determine whether commonly used commercial microbial proteases can be utilized to generate chia protein-based antibacterial and hypocholesterolemic hydrolysates/peptides, considering the effects of protein extraction method. Alcalase, Flavourzyme and sequential Alcalase-Flavourzyme were used to produce hydrolysates from chia protein (CF), protein-rich fraction (PRF) and chia protein concentrates (CPC1 and CPC2). These hydrolysates were evaluated for their antimicrobial activity against Gram-positive (G+) and Gram-negative (G?) microorganisms. The protein hydrolysates were purified by ultrafiltration through a membrane with 3 kDa nominal molecular weight, for evaluation of hypocholesterolemic activity. An inhibition zone was observed when the hydrolysate was tested against S. aureus, and minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were obtained. Peptides from chia protein with molecular mass lower than 3 kDa reduced up to 80.7% of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) enzymatic reaction velocity. It was also observed that, independent of the method used to obtain chia proteins, the fractions showed relevant bioactivity. Moreover, the intensity of the bioactivity varied with the method for obtaining the protein and with the enzyme used in the hydrolysis process. This is the first report to demonstrate that chia peptides are able to inhibit cholesterol homeostasis.  相似文献   
90.
This work investigates the degradation of Reactive Gray BF-2R dye (a blend of reactive yellow 145, reactive orange 122 and reactive black 5 dyes) using UV/H2O2, Fenton, and photo-Fenton-advanced oxidative processes, with artificial sunlight and UV-C radiations. The photo-Fenton process employing UV-C radiation was the most efficient under the conditions studied. The ideal conditions for the degradation of the dye, determined using a factorial design 23 and a study of the concentration of hydrogen peroxide ([H2O2]), were [H2O2] equal to 40 mg L?1, iron concentration [Fe] of 1 mg L?1, and pH between 3 and 4. The Chan and Chu non-linear kinetic model predicted the kinetic data with a degradation of over 98% for color and 68% for aromatics after 60 min. The behavior of the chemical oxygen demand fitted the first-order kinetic model well, with a degradation of 64% after 60 min. The Multilayer Perceptron 7-11-2 artificial neural network model enabled to model the degradation process of the aromatics and accurately predict the experimental data. Toxicity tests indicated that the post-treatment samples were non-toxic for Escherichia coli bacteria, and Portulaca grandiflora and Basil sabory seeds. However, they inhibited the growth of Lactuca sativa seeds and Salmonella enteritidis bacteria. The photo-Fenton process with UV-C radiation degraded the dye studied efficiently and the degradation percentages were, on average, 7% and 5% higher for color than those observed when employing the Fenton and UV/H2O2 processes, respectively. With the aromatic, however, they were 84% and 62% higher, thus justifying the use of this process.  相似文献   
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