869 resultados para reduced residues
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Abstract The giant hogweed (Heracleum mantegazzianum) has successfully invaded 19 European countries as well as parts of North America. It has become a problematic species due to its ability to displace native flora and to cause public health hazards. Applying population genetics to species invasion can help reconstruct invasion history and may promote more efficient management practice. We thus analysed levels of genetic variation and population genetic structure of H. mantegazzianum in an invaded area of the western Swiss Alps as well as in its native range (the Caucasus), using eight nuclear microsatellite loci together with plastid DNA markers and sequences. On both nuclear and plastid genomes, native populations exhibited significantly higher levels of genetic diversity compared to invasive populations, confirming an important founder event during the invasion process. Invasive populations were also significantly more differentiated than native populations. Bayesian clustering analysis identified five clusters in the native range that corresponded to geographically and ecologically separated groups. In the invaded range, 10 clusters occurred. Unlike native populations, invasive clusters were characterized by a mosaic pattern in the landscape, possibly caused by anthropogenic dispersal of the species via roads and direct collection for ornamental purposes. Lastly, our analyses revealed four main divergent groups in the western Swiss Alps, likely as a consequence of multiple independent establishments of H. mantegazzianum.
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Nonstructural protein 4B (NS4B) is a key organizer of hepatitis C virus (HCV) replication complex formation. In concert with other nonstructural proteins, it induces a specific membrane rearrangement, designated as membranous web, which serves as a scaffold for the HCV replicase. The N-terminal part of NS4B comprises a predicted and a structurally resolved amphipathic α-helix, designated as AH1 and AH2, respectively. Here, we report a detailed structure-function analysis of NS4B AH1. Circular dichroism and nuclear magnetic resonance structural analyses revealed that AH1 folds into an amphipathic α-helix extending from NS4B amino acid 4 to 32, with positively charged residues flanking the helix. These residues are conserved among hepaciviruses. Mutagenesis and selection of pseudorevertants revealed an important role of these residues in RNA replication by affecting the biogenesis of double-membrane vesicles making up the membranous web. Moreover, alanine substitution of conserved acidic residues on the hydrophilic side of the helix reduced infectivity without significantly affecting RNA replication, indicating that AH1 is also involved in virus production. Selective membrane permeabilization and immunofluorescence microscopy analyses of a functional replicon harboring an epitope tag between NS4B AH1 and AH2 revealed a dual membrane topology of the N-terminal part of NS4B during HCV RNA replication. Luminal translocation was unaffected by the mutations introduced into AH1, but was abrogated by mutations introduced into AH2. In conclusion, our study reports the three-dimensional structure of AH1 from HCV NS4B, and highlights the importance of positively charged amino acid residues flanking this amphipathic α-helix in membranous web formation and RNA replication. In addition, we demonstrate that AH1 possesses a dual role in RNA replication and virus production, potentially governed by different topologies of the N-terminal part of NS4B.
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Hypertension is a major public health problem and a leading cause of death and disability in both developed and developing countries, affecting onequarter of the world"s adult population. Our aim was to evaluate whether the consumption of gazpacho, a Mediterranean vegetable-based cold soup rich in phytochemicals, is associated with lower blood pressure (BP) and/or reduced prevalence of hypertension in individuals at high cardiovascular risk. Methods and results: We selected 3995 individuals (58% women, mean age 67 y) at high cardiovascular risk (81% hypertensive) recruited into the PREDIMED study. BP, weight, and dietary and physical activity data were collected. In multivariate linear regression analyses, after adjustment, moderate and high gazpacho consumption categories were associated with reduced mean systolic BP of 1.9 mm Hg [95% confidence interval (CI): 3.4; 0.6] and 2.6 mm Hg (CI: 4.2; 1.0), respectively, and reduced diastolic BP of 1.5 mm Hg (CI: 2.3; 0.6) and 1.9 mm Hg (CI: 2.8; 1.1). By multiple-adjusted logistic regression analysis, gazpacho consumption was associated with a lower prevalence of hypertension, with OR Z 0.85 (CI: 0.73; 0.99) for each 250 g/week increase and OR Z 0.73 (CI: 0.55; 0.98) for high gazpacho consumption groups compared to the no-consumption group. Conclusions: Gazpacho consumption was inversely associated with systolic and diastolic BP and prevalence of hypertension in a cross-sectional Mediterranean population at high cardiovascular risk. The association between gazpacho intake and reduction of BP is probably due to synergy among several bioactive compounds present in the vegetable ingredients used to make the recipe.
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Hypertension is a major public health problem and a leading cause of death and disability in both developed and developing countries, affecting onequarter of the world"s adult population. Our aim was to evaluate whether the consumption of gazpacho, a Mediterranean vegetable-based cold soup rich in phytochemicals, is associated with lower blood pressure (BP) and/or reduced prevalence of hypertension in individuals at high cardiovascular risk. Methods and results: We selected 3995 individuals (58% women, mean age 67 y) at high cardiovascular risk (81% hypertensive) recruited into the PREDIMED study. BP, weight, and dietary and physical activity data were collected. In multivariate linear regression analyses, after adjustment, moderate and high gazpacho consumption categories were associated with reduced mean systolic BP of 1.9 mm Hg [95% confidence interval (CI): 3.4; 0.6] and 2.6 mm Hg (CI: 4.2; 1.0), respectively, and reduced diastolic BP of 1.5 mm Hg (CI: 2.3; 0.6) and 1.9 mm Hg (CI: 2.8; 1.1). By multiple-adjusted logistic regression analysis, gazpacho consumption was associated with a lower prevalence of hypertension, with OR Z 0.85 (CI: 0.73; 0.99) for each 250 g/week increase and OR Z 0.73 (CI: 0.55; 0.98) for high gazpacho consumption groups compared to the no-consumption group. Conclusions: Gazpacho consumption was inversely associated with systolic and diastolic BP and prevalence of hypertension in a cross-sectional Mediterranean population at high cardiovascular risk. The association between gazpacho intake and reduction of BP is probably due to synergy among several bioactive compounds present in the vegetable ingredients used to make the recipe.
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AIMS/HYPOTHESIS: To assist in the development of preventive strategies, we studied whether the neighbourhood environment or modifiable behavioural parameters, including cardiorespiratory fitness (CRF) and physical activity (PA), are independently associated with obesity and metabolic risk markers in children. METHODS: We carried out a cross-sectional analysis of 502 randomly selected first and fifth grade urban and rural Swiss schoolchildren with regard to CRF, PA and the neighbourhood (rural vs urban) environment. Outcome measures included BMI, sum of four skinfold thicknesses, homeostasis model assessment of insulin resistance (HOMA-IR) and a standardised clustered metabolic risk score. RESULTS: CRF and PA (especially total PA, but also the time spent engaged in light and in moderate and vigorous intensity PA) were inversely associated with measures of obesity, HOMA-IR and the metabolic risk score, independently of each other, and of sociodemographic and nutritional parameters, media use, sleep duration, BMI and the neighbourhood environment (all p < 0.05). Children living in a rural environment were more physically active and had higher CRF values and reduced HOMA-IR and metabolic risk scores compared with children living in an urban environment (all p < 0.05). These differences in cardiovascular risk factors persisted after adjustment for CRF, total PA and BMI. CONCLUSIONS/INTERPRETATION: Reduced CRF, low PA and an urban environment are independently associated with an increase in metabolic risk markers in children.
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We report on the growth of epitaxial YBa2Cu3O7 thin films on X-cut LiNbO3 single crystals. The use of double CeO2/YSZ buffer layers allows a single in-plane orientation of YBa2Cu3O7, and results in superior superconducting properties. In particular, surface resistance Rs values of 1.4 m¿ have been measured at 8 GHz and 65 K. The attainment of such low values of Rs constitutes a key step toward the incorporation of high Tc materials as electrodes in photonic and acoustic devices.
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Several hypotheses have been elaborated to account for the evolutionary decay commonly observed in full-fledged Y chromosomes. Enhanced drift, background selection and selective sweeps, which are expected to result from reduced recombination, may all share responsibilities in the initial decay of proto-Y chromosomes, but little empirical information has been gathered so far. Here we take advantage of three markers that amplify on both of the morphologically undifferentiated sex chromosomes of the European tree frog (Hyla arborea) to show that recombination is suppressed in males (the heterogametic sex) but not in females. Accordingly, genetic variability is reduced on the Y, but in a way that can be accounted for by merely the number of chromosome copies per breeding pair, without the need to invoke background selection or selective sweeps.
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An analysis of latent fingermark residues by Sodium-Dodecyl-Sulfate PolyAcrylamide Gel Electrophoresis (SDS-PAGE) followed by silver staining allowed the detection of different proteins, from which two major bands, corresponding to proteins of 56 and 64 kDa molecular weight, could be identified. Two other bands, corresponding to proteins of 52 and 48 kDa were also visualizable along with some other weaker bands of lower molecular weights. In order to identify these proteins, three antibodies directed against human proteins were tested on western blots of fingermarks residues: anti-keratin 1 and 10 (K1/10), anti-cathepsin-D (Cat.D) and anti-dermcidin (Derm.). The corresponding antigens are known to be present in the stratum corneum of desquamating stratified epithelium (K1/10, Cat.D) and/or in eccrine sweat (Cat.D, Derm.). The two major bands were identified as consistent with keratin 1 and 10. The pro-form and the active form of the cathepsin-D have also been identified from two other bands. Dermcidin could not be detected in the western blot. In addition, these antibodies have been tested on latent fingermarks left on polyvinylidene fluoride (PVDF) membrane, as well as on whitened and non-whitened paper. The detection of fingermarks was successful with all three antibodies.
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BACKGROUND: Environmental conditions play a crucial role in mite growth, and optimal environmental control is key in the prevention of airway inflammation in chronic allergic rhinoconjunctivitis or asthma. OBJECTIVE: To evaluate the relationship between building energy performance and indoor mite allergen concentration in a cross-sectional study. METHODS: Major allergen concentration (Der f 1, Der p 1, mite group 2, Fel d 1 and Bla g 2) was determined by quantitative dot blot analysis from mattress and carpet dust samples in five buildings designed for low energy use (LEB) and in six control buildings (CB). Inhabitants had received 4 weeks prior to mite measurement a personal validated questionnaire related to the perceived state of health and comfort of living. RESULTS: Cumulative mite allergen concentration (with Der f 1 as the major contributor) was significantly lower in LEB as compared with CB both in mattresses and in carpets. In contrast, the two categories of buildings did not differ in Bla g 2 and Fel d 1 concentration, in the amount of dust and airborne mould collected. Whereas temperature was higher in LEB, relative humidity was significantly lower than in CB. Perceived overall comfort was better in LEB. CONCLUSIONS: Major mite allergen Der f 1 preferentially accumulates in buildings not specifically designed for low energy use, reaching levels at risk for sensitization. We hypothesize that controlled mechanical ventilation present in all audited LEB may favour lower air humidity and hence lower mite growth and allergen concentration, while preserving optimal perceived comfort.
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OBJECTIVE: Critically ill patients are at high risk of malnutrition. Insufficient nutritional support still remains a widespread problem despite guidelines. The aim of this study was to measure the clinical impact of a two-step interdisciplinary quality nutrition program. DESIGN: Prospective interventional study over three periods (A, baseline; B and C, intervention periods). SETTING: Mixed intensive care unit within a university hospital. PATIENTS: Five hundred seventy-two patients (age 59 ± 17 yrs) requiring >72 hrs of intensive care unit treatment. INTERVENTION: Two-step quality program: 1) bottom-up implementation of feeding guideline; and 2) additional presence of an intensive care unit dietitian. The nutrition protocol was based on the European guidelines. MEASUREMENTS AND MAIN RESULTS: Anthropometric data, intensive care unit severity scores, energy delivery, and cumulated energy balance (daily, day 7, and discharge), feeding route (enteral, parenteral, combined, none-oral), length of intensive care unit and hospital stay, and mortality were collected. Altogether 5800 intensive care unit days were analyzed. Patients in period A were healthier with lower Simplified Acute Physiologic Scale and proportion of "rapidly fatal" McCabe scores. Energy delivery and balance increased gradually: impact was particularly marked on cumulated energy deficit on day 7 which improved from -5870 kcal to -3950 kcal (p < .001). Feeding technique changed significantly with progressive increase of days with nutrition therapy (A: 59% days, B: 69%, C: 71%, p < .001), use of enteral nutrition increased from A to B (stable in C), and days on combined and parenteral nutrition increased progressively. Oral energy intakes were low (mean: 385 kcal*day, 6 kcal*kg*day ). Hospital mortality increased with severity of condition in periods B and C. CONCLUSION: A bottom-up protocol improved nutritional support. The presence of the intensive care unit dietitian provided significant additional progression, which were related to early introduction and route of feeding, and which achieved overall better early energy balance.
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In this paper, an advanced technique for the generation of deformation maps using synthetic aperture radar (SAR) data is presented. The algorithm estimates the linear and nonlinear components of the displacement, the error of the digital elevation model (DEM) used to cancel the topographic terms, and the atmospheric artifacts from a reduced set of low spatial resolution interferograms. The pixel candidates are selected from those presenting a good coherence level in the whole set of interferograms and the resulting nonuniform mesh tessellated with the Delauney triangulation to establish connections among them. The linear component of movement and DEM error are estimated adjusting a linear model to the data only on the connections. Later on, this information, once unwrapped to retrieve the absolute values, is used to calculate the nonlinear component of movement and atmospheric artifacts with alternate filtering techniques in both the temporal and spatial domains. The method presents high flexibility with respect to the required number of images and the baselines length. However, better results are obtained with large datasets of short baseline interferograms. The technique has been tested with European Remote Sensing SAR data from an area of Catalonia (Spain) and validated with on-field precise leveling measurements.
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The objective of this work was to evaluate the feasibility of different agro-residues as a carbon source in the fruiting substrates of Flammulina velutipesmushroom and the effect of supplementation with the nitrogen sources spent brewer's yeast and rice bran. The following fruiting substrates were evaluated: rubber wood sawdust (SD), paddy straw (PS), palm empty fruit bunches (EFB), and palm-pressed fiber (PPF). Cultivation was done on each agro-residue, based on formulations consisting of two substrates at the ratios of 3:1, 1:1, and 1:3. Mycelial growth rate and basidiocarp yield were evaluated. The best fruiting substrates were PS+EFB (25:75), PS+PPF (50:50), and PPF (100), with biological efficiency of 185.09±36.98, 150.89±50.35, and 129.06±14.51%, respectively. No significant effects of supplementation with rice bran and spent yeast were observed on mycelial growth rate and biological efficiency. The cultivation of F. velutipes on oil palm wastes does not require additional nitrogen sources.
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American Heart Journal Vol. 152, Issue 3, pp 538-542, 2006
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The death-inducing receptor Fas is activated when cross-linked by the type II membrane protein Fas ligand (FasL). When human soluble FasL (sFasL, containing the extracellular portion) was expressed in human embryo kidney 293 cells, the three N-linked glycans of each FasL monomer were found to be essential for efficient secretion. Based on the structure of the closely related lymphotoxin alpha-tumor necrosis factor receptor I complex, a molecular model of the FasL homotrimer bound to three Fas molecules was generated using knowledge-based protein modeling methods. Point mutations of amino acid residues predicted to affect the receptor-ligand interaction were introduced at three sites. The F275L mutant, mimicking the loss of function murine gld mutation, exhibited a high propensity for aggregation and was unable to bind to Fas. Mutants P206R, P206D, and P206F displayed reduced cytotoxicity toward Fas-positive cells with a concomitant decrease in the binding affinity for the recombinant Fas-immunoglobulin Fc fusion proteins. Although the cytotoxic activity of mutant Y218D was unaltered, mutant Y218R was inactive, correlating with the prediction that Tyr-218 of FasL interacts with a cluster of three basic amino acid side chains of Fas. Interestingly, mutant Y218F could induce apoptosis in murine, but not human cells.
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The establishment of legislative rules about explosives in the eighties has reduced the illicit use of military and civilian explosives. However, bomb-makers have rapidly taken advantage of substances easily accessible and intended for licit uses to produce their own explosives. This change in strategy has given rise to an increase of improvised explosive charges, which is moreover assisted by the ease of implementation of the recipes, widely available through open sources. While the nature of the explosive charges has evolved, instrumental methods currently used in routine, although more sensitive than before, have a limited power of discrimination and allow mostly the determination of the chemical nature of the substance. Isotope ratio mass spectrometry (IRMS) has been applied to a wide range of forensic materials. Conclusions drawn from the majority of the studies stress its high power of discrimination. Preliminary studies conducted so far on the isotopic analysis of intact explosives (pre-blast) have shown that samples with the same chemical composition and coming from different sources could be differentiated. The measurement of stable isotope ratios appears therefore as a new and remarkable analytical tool for the discrimination or the identification of a substance with a definite source. However, much research is still needed to assess the validity of the results in order to use them either in an operational prospect or in court. Through the isotopic study of black powders and ammonium nitrates, this research aims at evaluating the contribution of isotope ratio mass spectrometry to the investigation of explosives, both from a pre-blast and from a post-blast approach. More specifically, the goal of the research is to provide additional elements necessary to a valid interpretation of the results, when used in explosives investigation. This work includes a fundamental study on the variability of the isotopic profile of black powder and ammonium nitrate in both space and time. On one hand, the inter-variability between manufacturers and, particularly, the intra-variability within a manufacturer has been studied. On the other hand, the stability of the isotopic profile over time has been evaluated through the aging of these substances exposed to different environmental conditions. The second part of this project considers the applicability of this high-precision technology to traces and residues of explosives, taking account of the characteristics specific to the field, including their sampling, a probable isotopic fractionation during the explosion, and the interferences with the matrix of the site.