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41.
42.
The incidence of chronic renal diseases is increasing worldwide, and there is a great need to identify therapies capable of arresting or reducing disease progression. The current treatment of chronic nephropathies is limited to angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, but increasing clinical and experimental evidence suggests that statins could play a therapeutic role. Ultrastructural studies have shown the presence of gap junctions within all the cells of the glomerulus and podocytes have been found to contain primarily connexin-43. The present study aims to observe the beneficial effects of rosuvastatin on structural and ultrastructural renal morphology and on glomerular connexin-43 expression in normotensive rats and spontaneously hypertensive rats (SHR). Rats were randomly allocated into four groups: WKY-C: normotensive animals no receiving rosuvastatin; WKY-ROS: normotensive animals receiving rosuvastatin; SHR-C: hypertensive animals no receiving rosuvastatin; SHR-ROS: hypertensive animals receiving rosuvastatin. Our results show no differences in blood urea, creatinine, uric acid and creatine phosphokinase levels between the groups, however, there was an decreasing of 24-h protein excretion in SHR-ROS. Capsular area in SHR-ROS was decreased, however, there was no alteration in urinary space. By transmission electron microscopy the slit diaphragm and podocyte foot processes were more preserved in SHR-ROS. By scanning electron microscopy the podocyte foot processes were more preserved in SHR-ROS. Increased connexin-43 immunofluorescence was observed in glomeruli of WKY-ROS and SHR-ROS. In conclusion, we hypothesize that renal pleiotropic effect of rosuvastatin can be a therapeutic tool for improving kidney ultrastructure and, consequently, renal function in hypertensive individuals.  相似文献   
43.
Tomato high pigment (hp) mutants represent an interesting horticultural resource due to their enhanced accumulation of carotenoids, flavonoids and vitamin C. Since hp mutants are known for their exaggerated light responses, the molecules accumulated are likely to be antioxidants, recruited to deal with light and others stresses. Further phenotypes displayed by hp mutations are reduced growth and an apparent disturbance in water loss. Here, we examined the impact of the hp1 mutation and its near isogenic line cv Micro-Tom (MT) on stomatal conductance (gs), transpiration (E), CO(2) assimilation (A) and water use efficiency (WUE). Detached hp1 leaves lost water more rapidly than control leaves, but this behaviour was reversed by exogenous abscisic acid (ABA), indicating the ability of hp1 to respond to this hormone. Although attached hp1 leaves had enhanced gs, E and A compared to control leaves, genotypic differences were lost when water was withheld. Both instantaneous leaf-level WUE and long-term whole plant WUE did not differ between hp1 and MT. Our results indicate a link between exaggerated light response and water loss in hp1, which has important implications for the use of this mutant in both basic and horticultural research.  相似文献   
44.
Enzymatic synthesis of fructose fatty acid ester was performed in organic solvent media, using a purified lipase from Candida antartica B immobilized in acrylic resin. Response surface methodology with a central composite rotatable design based on five levels was implemented to optimize three experimental operating conditions (temperature, agitation and reaction time). A statistical significant cubic model was established. Temperature and reaction time were found to be the most significant parameters. The optimum operational conditions for maximizing the synthesis of fructose esters were 57.1°C, 100 rpm and 37.8 h. The model was validated in the identified optimal conditions to check its adequacy and accuracy, and an experimental esterification percentage of 88.4% (±0.3%) was obtained. These results showed that an improvement of the enzymatic synthesis of fructose esters was obtained under the optimized conditions.  相似文献   
45.
Manu National Park of southern Peru is one of the most renowned protected areas in the world, yet large-bodied vertebrate surveys conducted to date have been restricted to Cocha Cashu Biological Station, a research station covering <0.06 percent of the 1.7 Mha park. Manu Park is occupied by >460 settled Matsigenka Amerindians, 300–400 isolated Matsigenka, and several, little-known groups of isolated hunter–gatherers, yet the impact of these native Amazonians on game vertebrate populations within the park remains poorly understood. On the basis of 1495 km of standardized line-transect censuses, we present density and biomass estimates for 23 mammal, bird, and reptile species for seven lowland and upland forest sites in Manu Park, including Cocha Cashu. We compare these estimates between hunted and nonhunted sites within Manu Park, and with other Neotropical forest sites. Manu Park safeguards some of the most species-rich and highest biomass assemblages of arboreal and terrestrial mammals ever recorded in Neotropical forests, most likely because of its direct Andean influence and high levels of soil fertility. Relative to Barro Colorado Island, seed predators and arboreal folivores in Manu are rare, and generalist frugivores specializing on mature fruit pulp are abundant. The impact of such a qualitative shift in the vertebrate community on the dynamics of plant regeneration, and therefore, on our understanding of tropical plant ecology, must be profound. Despite a number of external threats, Manu Park continues to serve as a baseline against which other Neotropical forests can be gauged. Abstract in Spanish is available at http://www.blackwell-synergy.com/loi/btp .  相似文献   
46.
Recent changes in Brazilian legislation for commercial disinfectants have been published due to the recent epidemic of nosocomial infections caused by rapidly growing mycobacteria (RGM) in many states of Brazil over the last 8 years. One of these documents requires that all the manufacturers provide evidence of efficacy of sterilizing and disinfectant products, used for semi critical medical devices, against the Mycobacterium bovis BCG Moreau and Mycobacterium abscessus subsp. bolletii INCQS 00594 strains by using the Confirmative in vitro Test for Determining Tuberculocidal Activity of Disinfectants recommended by the Association of Official Analytical Chemists. These changes have caused additional costs and increased problems for importation of enrichment products at national laboratories where disinfectant efficacy assay service is performed. Middlebrook ADC Enrichment (ADC) is provided by a unique manufacturer and used in the official protocol. The aim of the present study was to evaluate an alternative in house low-cost enrichment composed of fetal bovine serum and glucose (FBSG) with ADC for performance of disinfectant efficacy assay against mycobacteria. After obtaining the growth curves for M. abscessus ATCC 19977, M. abscessus subsp. bolletii INCQS 00594, Mycobacterium chelonae ATCC 35752, and Mycobacterium fortuitum ATCC 6841 by using ADC enrichment and FBSG in Kirchners and 7H9 culture media. Through statistical analysis via the Kruskal-Wallis test on the evaluation of microorganism growth rate, it was observed that there was no inhibition of RGM growth by any of the enrichments used. These results suggest that low-cost enrichment FBSG may be used as a potential substitute of ADC for composition of media for mycobacterial growth, including in disinfectant tests.  相似文献   
47.
Amazonian countryside habitats provide limited avian conservation value   总被引:1,自引:0,他引:1  
Balancing ever-increasing agricultural and biofuel needs with biodiversity conservation is one of the greatest challenges facing conservation biologists in the 21st century. The conversion of >75 million hectares of forests in Brazilian Amazonia over four decades for agropastoral uses has resulted in the ‘creation’ of a similar-sized amount of non-forest ‘agricultural matrix’ habitats. Despite extensive research on the effects of forest loss and fragmentation on the Amazonian biota, the value of increasingly larger areas of non-forest habitat for forest wildlife remains poorly understood. We conducted 325 fixed-radius point counts of the avifaunal assemblage of non-forest vegetation within a 1200-km2 region along the Amazonian ‘Arc of Deforestation’ in Northern Mato Grosso, Brazil. Our sampling included 2,814 records of 164 species, 15 and 54% of which were recorded in more than 10% and fewer than 2% of all sampling sites, respectively. In particular, nearly 70% of the regional scale avifauna of 560 species failed to use the agricultural matrix, regardless of the persistence of ameliorating structural features, such as isolated trees. At the local scale, higher species richness in the agricultural matrix was best predicted by the presence of relictual trees, and to a lesser extent by standing water and scrubby habitats. The presence of relictual trees, rather than scrub, predicted the occurrence of those forest-dependent species that did use the agricultural matrix. Our results indicate that intensive agricultural production coupled with land sparing would better suit conservation of vulnerable forest species than more extensive ‘wildlife friendly’ agricultural practices that require more land under production to produce the same yield.  相似文献   
48.
Specialized seed predators are uncommon in arboreal vertebrate assemblages, and the hypothesis that consuming seeds of immature fruits – which may be available for relatively long periods compared to mature fruit – could reduce seasonal food scarcity experienced by generalist frugivores remains largely untested. To test this hypothesis, we examined the diet and feeding ecology of bald‐faced saki monkeys Pithecia irrorata in a largely intact forest mosaic of southeastern Peru based on systematic monitoring of five habituated groups over a three‐year period and compared the relative availability of ripe and unripe fruits in their diet. Plant phenology data from individual tree crowns showed that, compared to ripe fruits, immature fruits were available in more tree species, in greater quantities, and for longer periods. Despite pronounced community‐wide seasonal changes in fruit production at our study area, feeding patterns of bald‐faced saki remained largely invariant: fruits comprised approximately 95% of the species’ monthly diet, with seeds alone accounting for 75%, with no major monthly dietary shifts. The flexible exploitation by this species of a consistently available food supply for which it faces little competition likely reduces foraging effort and consumption of less desirable foods, even during prolonged periods of overall fruit scarcity. The relative rarity of immature fruit specialists in tropical forests may reflect the fact that processing the hard pericarps and neutralizing the toxicities of immature seeds present substantial evolutionary hurdles that few arboreal vertebrate species have overcome.  相似文献   
49.
In the process analytical technology (PAT) initiative, the application of sensors technology and modeling methods is promoted. The emphasis is on Quality by Design, online monitoring, and closed-loop control with the general aim of building in product quality into manufacturing operations. As a result, online high-throughput process analyzers find increasing application and therewith high amounts of highly correlated data become available online. In this study, an hybrid chemometric/mathematical modeling method is adopted for data analysis, which is shown to be advantageous over the commonly used chemometric techniques in PAT applications. This methodology was applied to the analysis of process data of Bordetella pertussis cultivations, namely online data of near-infrared, (NIR), pH, temperature and dissolved oxygen, and off-line data of biomass, glutamate, and lactate concentrations. The hybrid model structure consisted of macroscopic material balance equations in which the specific reactions rates are modeled by nonlinear partial least square (PLS). This methodology revealed a significant higher statistical confidence in comparison to PLSs, translated in a reduction of mean squared prediction errors (e.g., individual root mean squared prediction errors calibration/validation obtained through the hybrid model for the concentrations of lactate: 0.8699/0.7190 mmol/L; glutamate: 0.6057/0.2917 mmol/L; and biomass: 0.0520/0.0283 OD; and obtained through the PLS model for the concentrations of lactate: 1.3549/1.0087 mmol/L; glutamate: 0.7628/0.3504 mmol/L; and biomass: 0.0949/0.0412 OD). Moreover, the analysis of loadings and scores in the hybrid approach revealed that process features can, as for PLS, be extracted by the hybrid method.  相似文献   
50.
Cancer cachexia is a multifaceted syndrome whose aetiology is extremely complex and is directly related to poor patient prognosis and survival. Changes in lipid metabolism in cancer cachexia result in marked reduction of total fat mass, increased lipolysis, total oxidation of fatty acids, hyperlipidaemia, hypertriglyceridaemia, and hypercholesterolaemia. These changes are believed to be induced by inflammatory mediators, such as tumour necrosis factor-α (TNF-α) and other factors.Attention has recently been drawn to the current theory that cachexia is a chronic inflammatory state, mainly caused by the host’s reaction to the tumour. Changes in expression of numerous inflammatory mediators, notably in white adipose tissue (WAT), may trigger several changes in WAT homeostasis. The inhibition of adipocyte differentiation by PPARγ is paralleled by the appearance of smaller adipocytes, which may partially account for the inhibitory effect of PPARγ on inflammatory gene expression. Furthermore, inflammatory modulation and/or inhibition seems to be dependent on the IKK/NF-κB pathway, suggesting that a possible interaction between NF-κB and PPARγ is required to modulate WAT inflammation induced by cancer cachexia.In this article, current literature on the possible mechanisms of NF-κB and PPARγ regulation of WAT cells during cancer cachexia are discussed. This review aims to assess the role of a possible interaction between NF-κB and PPARγ in the setting of cancer cachexia as well as its significant role as a potential modulator of chronic inflammation that could be explored therapeutically.  相似文献   
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