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The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children.  相似文献   
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Temperate species are projected to experience the greatest temperature increases across a range of modelled climate change scenarios, and climate warming has been linked to geographical range and population changes of individual species at such latitudes. However, beyond the multiple modelling approaches, we lack empirical evidence of contemporary climate change impacts on populations in broad taxonomic groups and at continental scales. Identifying reliable predictors of species resilience or susceptibility to climate warming is of critical importance in assessing potential risks to species, ecosystems and ecosystem services. Here we analysed long‐term trends of 110 common breeding birds across Europe (20 countries), to identify climate niche characteristics, adjusted to other environmental and life history traits, that predict large‐scale population changes accounting for phylogenetic relatedness among species. Beyond the now well‐documented decline of farmland specialists, we found that species with the lowest thermal maxima (as the mean spring and summer temperature of the hottest part of the breeding distribution in Europe) showed the sharpest declines between 1980 and 2005. Thermal maximum predicted the recent trends independently of other potential predictors. This study emphasizes the need to account for both land‐use and climate changes to assess the fate of species. Moreover, we highlight that thermal maximum appears as a reliable and simple predictor of the long‐term trends of such endothermic species facing climate change.  相似文献   
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The objective of this study was to evaluate the effects of six activating solutions on duration of sperm motility, fertilization rate (FR), and hatching rate (HR) of Prochilodus lineatus (Valenciennes, 1837). The activating solutions (SA) used were: SA0 (199 mOsm kg?1, pH 8.5), SA1 (138 mOsm kg?1, pH 7.5), SA2 (256 mOsm kg?1, pH 7.5), SA3 (131 mOsm kg?1, pH 10), NaCl (92 mOsm kg?1, pH 7.5) and distilled water (32 mOsm kg?1, pH 7.5). SA1 induced the highest motility, FR and HR, compared with the other activating solutions. The lowest motility was obtained with SA0, with no fertilization or hatching, whereas motility was zero with SA2 and SA3. It is possible to conclude that the solution SA1 can be used for the activation of gametes during fertilization in induced reproduction of curimba to achieve higher fertilization and hatching rates. Thus, it was found that the osmolality and pH of activating solutions, probably with the participation of dissolved substances therein, are the main factors acting on semen motility after activation.  相似文献   
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Focal and segmental glomerulosclerosis (FSGS) is one of the most important renal diseases related to end-stage renal failure. Bradykinin has been implicated in the pathogenesis of renal inflammation, whereas the role of its receptor 2 (B2RBK; also known as BDKRB2) in FSGS has not been studied. FSGS was induced in wild-type and B2RBK-knockout mice by a single intravenous injection of Adriamycin (ADM). In order to further modulate the kinin receptors, the animals were also treated with the B2RBK antagonist HOE-140 and the B1RBK antagonist DALBK. Here, we show that the blockage of B2RBK with HOE-140 protects mice from the development of FSGS, including podocyte foot process effacement and the re-establishment of slit-diaphragm-related proteins. However, B2RBK-knockout mice were not protected from FSGS. These opposite results were due to B1RBK expression. B1RBK was upregulated after the injection of ADM and this upregulation was exacerbated in B2RBK-knockout animals. Furthermore, treatment with HOE-140 downregulated the B1RBK receptor. The blockage of B1RBK in B2RBK-knockout animals promoted FSGS regression, with a less-inflammatory phenotype. These results indicate a deleterious role of both kinin receptors in an FSGS model and suggest a possible cross-talk between them in the progression of disease.KEY WORDS: Focal and segmental glomerulosclerosis, Bradykinin receptors, Inflammation, Podocyte, Fibrosis  相似文献   
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Summary. Mesial temporal lobe epilepsy (MTLE), the most common form of epilepsy, is characterised by cytoarchitectural abnormalities including neuronal cell loss and reactive gliosis in hippocampus. Determination of aberrant cytoskeleton protein expression by proteomics techniques may help to understand pathomechanism that is still elusive. We searched for differential expression of hippocampal proteins by an analytical method based on two-dimensional gel electrophoresis (2-DE) coupled with mass spectrometry unambiguously identifying 77 proteins analysed in eight control and eight MTLE hippocampi. Proteins were quantified and we observed 18 proteins that were altered in MTLE. Cytoskeleton proteins tubulin α-1 chain, β-tubulin, profilin II, neuronal tropomodulin were significantly reduced and one actin spot was missing, whereas ezrin and vinculin were significantly increased in MTLE. Proteins of several classes as e.g. antioxidant proteins (peroxiredoxins 3 and 6), chaperons (T-complex protein 1-α, stress-induced-phosphoprotein 1), signaling protein MAP kinase kinase 1, synaptosomal proteins (synaptotagmin I, α-synuclein), NAD-dependent deacetylase sirtuin-2 and 26S protease regulatory subunit 7 protein, neuronal-specific septin 3 were altered in MTLE. Taken together, the findings may represent or lead to cytoskeletal impairment; aberrant antioxidant proteins, chaperons, MAP kinase kinase 1 and NAD-dependent deacetylase sirtuin-2 may have been involved in pathogenetic mechanisms and altered synaptosomal protein expression possibly reflects synaptic impairment in MTLE. J. W. Yang and T. Czech have equally contributed to the paper.  相似文献   
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One hundred and twenty-eight specimens of namorado sandperches, 62 P. numida and 66 P. semifasciata, collected between October 2002 and June 2003 off the Cabo Frio, Rio de Janeiro, Brazil (Lat 23 degrees S and Long 42 degrees W), were examined to study their metazoan parasites. Parasite communities of these fish were composed basically of endoparasites, mainly digenean and cestodes species, with low prevalence and abundance but having high parasite species richness values (at the component community level). Among these values, that found for P. numida is the highest so far recorded for marine fishes from the Neotropical Region. Thirty-nine species of metazoan parasites were collected: 36 from P. numida and 28 from P. semifasciata. Twenty-five parasite species were common to both species of namorado sandperches. Pseudopercis numida and P. semifasciata are new host records for all parasite species collected, with the exception of Microcotyle pseudopercis. Choanodera sp., Leurodera decora, Neolebouria georgenascimentoi, and Proctoeces sp. which were recorded for the first time in the South American Atlantic Ocean. Gnathia sp. from P. numida and Scolex pleuronectis from P. semifasciata were the species having the greatest dominance frequency. Parasite abundance in P. numida and P. semifasciata were positively correlated with the host total length. Only in P. numida was parasite species richness correlated positively with the host total length. No significant differences between endoparasite infracommunities of P. numida and P. semifasciata were detected. The ectoparasites of P. numida had higher values for parasite abundance, parasite richness, Brillouin index, evenness index, and Berger-Parker index than those of the ectoparasites of P. semifasciata. Comparisons among all ecto- and endoparasites showed the ectoparasites of P. numida as the most heterogeneous group. Low similarity values were observed among the three types of parasite infracommunities of the two hosts.  相似文献   
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Lesion development in tegumentary leishmaniasis is markedly influenced by the inoculation site and the type and number of injected infective forms. This and the yet unclear contribution of Th2 cytokines as susceptibility factors to Leishmania amazonensis infection prompted us to investigate the roles of IL-4, IL-13 and IL-10 on C57BL/6 and BALB/c mice infected in the footpad (paw) or rump with low-dose L. amazonensis purified-metacyclics. Wild-type (WT) mice of either strain developed, in the rump, a single large ulcerated lesion whereas paw lesions never ulcerated and were much smaller in C57BL/6 than in BALB/c mice. However, rump-inoculated IL-4-deficient (IL-4(-/-)) C57BL/6 mice did not develop any visible lesions although parasites remained in the dermis and lymph nodes, even after systemic IL-10-receptor blocking. By comparison, all IL-4(-/-) BALB/c mice developed rump ulcers. Strikingly, only 30% of rump-infected IL-4Rα(-/-) BALB/c mice developed lesions. IL-4(-/-) mice had higher IFN-γ and lower IL-10 and IL-13 levels than WT mice. Paw-infected IL-4Rα(-/-) BALB/c mice developed minimal paw lesions. While other factors contributing to L. amazonensis susceptibility cannot be discounted, our results indicate that absent signalling by IL-4 or by IL-4/IL-13 have more intense attenuating effects on rump than on paw lesions but do not eradicate parasitism.  相似文献   
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