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31.
Williams-Beuren syndrome (WBS), caused by a heterozygous deletion at 7q11.23, represents a model for studying hypertension, the leading risk factor for mortality worldwide, in a genetically determined disorder. Haploinsufficiency at the elastin gene is known to lead to the vascular stenoses in WBS and is also thought to predispose to hypertension, present in approximately 50% of patients. Detailed clinical and molecular characterization of 96 patients with WBS was performed to explore clinical-molecular correlations. Deletion breakpoints were precisely defined and were found to result in variability at two genes, NCF1 and GTF2IRD2. Hypertension was significantly less prevalent in patients with WBS who had the deletion that included NCF1 (P=.02), a gene coding for the p47(phox) subunit of the NADPH oxidase. Decreased p47(phox) protein levels, decreased superoxide anion production, and lower protein nitrotyrosination were all observed in cell lines from patients hemizygous at NCF1. Our results indicate that the loss of a functional copy of NCF1 protects a proportion of patients with WBS against hypertension, likely through a lifelong reduced angiotensin II-mediated oxidative stress. Therefore, antioxidant therapy that reduces NADPH oxidase activity might have a potential benefit in identifiable patients with WBS in whom serious complications related to hypertension have been reported, as well as in forms of essential hypertension mediated by a similar pathogenic mechanism.  相似文献   
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The mating call of Isoperla bipartita is described. The male call is composed of 3–10 groups, each of 1–4 rubs. The times between rubs average 89.52 msec (between first and second), 43.52 msec (between second and third) and 35.28 msec (between third and fourth). The time between two groups averages 180.75 msec and varies from 142 to 290 msec. The female answer is composed of a beat and rub repeated at 479.09 msec intervals on average and interspersed between the male call groups between 94 and 184 msec (mean = 118.11 msec) after the last rub of the male group. The I. bipartita call can be considered as a ‘complex and modified pattern’ because the male produces calls of 1–4 rubs by group and the female answers overlapping the male call by percussion-rubbing-produced signals. Moreover, it is different from other studied Iberian Isoperla calls, being probably a species-specific behavioural pattern.  相似文献   
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We investigate for the first time the influence of heart failure (HF) on nucleolar organization and proteins in patients with ischemic (ICM) or dilated cardiomyopathy (DCM). A total of 71 human hearts from ICM (n=38) and DCM (n=27) patients, undergoing heart transplantation and control donors (n=6), were analysed by western-blotting, RT-PCR and cell biology methods. When we compared protein levels according to HF etiology, nucleolin was increased in both ICM (117%, p<0.05) and DCM (141%, p<0.01). Moreover, mRNA expression were also upregulated in ICM (1.46-fold, p<0.05) and DCM (1.70-fold, p<0.05. Immunofluorescence studies showed that the highest intensity of nucleolin was into nucleolus (p<0.0001), and it was increased in pathological hearts (p<0.0001). Ultrastructure analysis by electron microscopy showed an increase in the nucleus and nucleolus size in ICM (17%, p<0.05 and 131%, p<0.001) and DCM (56%, p<0.01 and 69%, p<0.01). Nucleolar organization was influenced by HF irrespective of etiology, increasing fibrillar centers (p<0.001), perinucleolar chromatin (p<0.01) and dense fibrillar components (p<0.01). Finally, left ventricular function parameters were related with nucleolin levels in ischemic hearts (p<0.0001). The present study demonstrates that HF influences on morphology and organization of nucleolar components, revealing changes in the expression and in the levels of nucleolin protein.  相似文献   
35.
Olive pollen is one of the main causes of allergy in Mediterranean countries. Ole e 6, an olive pollen allergen, is a small (5.8 kDa) and acidic protein (pI 4.2) and no homologous proteins have been isolated or characterized so far. Ole e 6 has been efficiently expressed in the methylotrophic yeast Pichia pastoris. The cDNA encoding Ole e 6 was inserted into the plasmid vector pPIC9 and overexpressed in GS115 yeast cells. The recombinant product was purified by size-exclusion chromatography followed by reverse-phase HPLC. N-terminal sequencing, amino acid composition analysis, CD, NMR, and IgG-binding experiments were employed to characterize the purified protein. NMR data revealed the oxidation of the methionine at position 28 in approximately 50% of the recombinant protein but, although this alters its electrophoretic behavior, it did not affect folding or IgG-binding properties of rOle e 6. The recombinant form of Ole e 6 expressed in P. pastoris can be employed for structural and biochemical studies.  相似文献   
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The conservation of endangered species requires accurate data, and knowledge of cause-specific mortality rates is one of the most important issues. In recent years, conservation programs for the critically endangered Iberian lynx Lynx pardinus have been developed on the basis of mortality data derived 30 years ago from the small Doñana population. Thus, there is an urgent need for an update of mortality rates and causes in both populations (Sierra Morena and Doñana). Here we use radio-tracking information from the whole range of the Iberian lynx to quantify mortality rates and identify their causes. Between 2006 and 2011, we radio-tagged 78 Iberian lynxes from its two remaining populations (39 from Sierra Morena and 39 from Doñana). Mortality events were evaluated to identify causes, and cause-specific annual mortality rates (AMR) were obtained using the nonparametric cumulative incidence function estimator. Overall, AMR was estimated at 0.16?±?0.05 (0.19?±?0.09 in Sierra Morena and 0.12?±?0.07 in Doñana). Disease was the main cause of mortality both for the whole population and the Doñana population. Poaching was the main cause of mortality in Sierra Morena. Our results suggest that the best strategy for conserving this species is to focus action on decreasing the fatal effect of disease and poaching. Given the possible existence of an underlying inbreeding-mediated immunosuppression, genetic management aimed at increasing the genetic diversity of this population is also recommended.  相似文献   
38.
The present study was carried out in the marine area of Stratoni, Greece, where two seahorse species are present (Hippocampus hippocampus and Hippocampus guttulatus). Two surveys were conducted (September 2016 and May 2019) to gather information regarding seahorse species' abundance, distribution and habitat characteristics. Four different seahorse natural and artificial habitat types were identified. The results revealed that the presence of H. hippocampus was relatively high, especially at sites with artificial structures, whereas the presence of H. guttulatus was rare. Data collected can provide baseline information for future population assessments.  相似文献   
39.
As surface temperatures are expected to rise in the future, ice‐rich permafrost may thaw, altering soil topography and hydrology and creating a mosaic of wet and dry soil surfaces in the Arctic. Arctic wetlands are large sources of CH4, and investigating effects of soil hydrology on CH4 fluxes is of great importance for predicting ecosystem feedback in response to climate change. In this study, we investigate how a decade‐long drying manipulation on an Arctic floodplain influences CH4‐associated microorganisms, soil thermal regimes, and plant communities. Moreover, we examine how these drainage‐induced changes may then modify CH4 fluxes in the growing and nongrowing seasons. This study shows that drainage substantially lowered the abundance of methanogens along with methanotrophic bacteria, which may have reduced CH4 cycling. Soil temperatures of the drained areas were lower in deep, anoxic soil layers (below 30 cm), but higher in oxic topsoil layers (0–15 cm) compared to the control wet areas. This pattern of soil temperatures may have reduced the rates of methanogenesis while elevating those of CH4 oxidation, thereby decreasing net CH4 fluxes. The abundance of Eriophorum angustifolium, an aerenchymatous plant species, diminished significantly in the drained areas. Due to this decrease, a higher fraction of CH4 was alternatively emitted to the atmosphere by diffusion, possibly increasing the potential for CH4 oxidation and leading to a decrease in net CH4 fluxes compared to a control site. Drainage lowered CH4 fluxes by a factor of 20 during the growing season, with postdrainage changes in microbial communities, soil temperatures, and plant communities also contributing to this reduction. In contrast, we observed CH4 emissions increased by 10% in the drained areas during the nongrowing season, although this difference was insignificant given the small magnitudes of fluxes. This study showed that long‐term drainage considerably reduced CH4 fluxes through modified ecosystem properties.  相似文献   
40.
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