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151.
Celiac disease (CD) is an autoimmune permanent enteropathy that is triggered in susceptible individuals after the ingestion of gluten, a storage protein fraction presents in wheat, rye and barley endosperm. Specific gluten peptides can bind to HLA-DQ2/8 and induce lamina propria CD4+ T cell responses causing damage of the small intestine mucosa. Recent studies suggested that beside immunodominant and toxic epitopes, wheat gluten also contains epitopes capable of preventing the mucosal response in vitro. Among them, a decapeptide (QQPQDAVQPF) from wheat was reported to have an antagonist effect on the agglutination of K562(S) cells and celiac T-cell activation, although the corresponding nucleotidic sequence remained unknown. This study was therefore designed to clone the sequence encoding the protein carrying the decapetide with CD protective properties. A ω-secalin gene encoding containing the decapeptide QQPQRPQQPF was isolated. Although the decapeptide was not identical to the one previously described, QQPQRPQQPF showed the same capability to prevent K562(S) cell agglutination and celiac mucosa immune activation induced by toxic gliadins. The ω-secalin gene was found in wheat carrying the wheat–rye chromosomal translocations 1BL.1RS. The identification of this immunomodulatory gliadin sequence, naturally occurring in cultivars of wheat toxic for celiac patients, might offer new therapeutic strategies for CD.  相似文献   
152.
In this paper, we estimate the distribution of population by exposure to multiple airborne pollutants, taking into account the spatio-temporal variability of daily air quality and the high-resolution spatial spread of human population around Europe. In particular, we consider monitoring network data for five pollutants, namely carbon monoxide, nitrogen dioxide, ozone, coarse and fine particulate matters. The spatial information contained in the large dataset of daily continental air quality is exploited using a multivariate spatio-temporal model capable to cover cross correlation among pollutants, covariates, and missing data as well as spatial and temporal variability and correlation. At the same time, the model is simple enough to be feasible for the large dataset of daily continental air quality over three years. Maximum likelihood estimation is performed using the EM algorithm, and kriging-like spatial estimates are used to compute high-resolution exposure distribution. Moreover, a novel semi-parametric bootstrap technique is used to assess the exposure distribution uncertainty. In this way, we compare the daily population exposure of 33 European countries and three important metropolitan areas in years 2009–2011 using a single flexible model. Extensive tabulations and graphs are reported in the supplementary material.  相似文献   
153.
Multi-environment trials represent a highly valuable tool for the identification of the genetic bases of crop yield potential and stress adaptation. A Diversity Array Technology®-based barley map has been developed in the ‘Nure’ × ‘Tremois’ biparental Doubled Haploid population, harbouring the genomic position of a gene set with a putative role in the regulation of flowering time and abiotic stress response in barley. The population has been evaluated in eighteen location-by-year combinations across the Mediterranean basin. QTL mapping identified several genomic regions responsible for barley adaptation to Mediterranean conditions in terms of phenology, grain yield and yield component traits. The most frequently detected yield QTL had the early flowering HvCEN_EPS2 locus (chromosome 2H) as peak marker, showing a positive effect from the early winter parent ‘Nure’ in eight field trials, and explaining up to 45.8 % of the observed variance for grain yield. The HvBM5A_VRN-H1 locus on chromosome 5H and the genomic region possibly corresponding to PPD-H2 on chromosome 1H were significantly associated to grain yield in five and three locations, respectively. Environment-specific QTLs for grain yield, and clusters of yield component QTLs not related to phenology and or developmental genes (e.g. on chromosome 4H, BIN_09) were observed as well. The results of this work provide a valuable source of knowledge and tools for both explaining the genetic bases of barley yield adaptation across the Mediterranean basin, and using QTL-associated markers for MAS pre-breeding and breeding programmes.  相似文献   
154.
Thiacloprid (TCP) is a widely used neonicotinoid insecticide with a probable toxic hazard to animals and human beings. This hazard has intensified the demand for natural compounds to alleviate the expected toxic insults. This study aimed at determining whether astaxanthin (ASX) could mitigate the hepatotoxic effect of TCP and diminish its suppressive effect on immune responses in rats. Animals received TCP by gavage at 62.1 mg/kg (1/10th LD50) with or without ASX at 40 mg/kg for 60 days. Intoxicated rats showed modulation of serum transaminases and protein profiles. The hemagglutination antibody titer to sheep red blood cells (SRBC) and the number of plaque-forming cells in the spleen were reduced. The cell-mediated immunity and phagocytosis were suppressed, while serum interleukins IL-1β, IL-6, and IL-10 were elevated. Additionally, malondialdehyde, nitric oxide, and 8-hydroxy-2′-deoxyguanosine levels were increased in the liver, spleen, and thymus, with depletion of glutathione and suppression of superoxide dismutase and catalase activities. The expressions of inducible nitric oxide synthase and the high mobility group box protein 1 genes were upregulated with histomorphological alterations in the aforementioned organs. Cotreatment with ASX markedly ameliorated the toxic effects of TCP, and all markers showed a regression trend towards control values. Collectively, our data suggest that the protective effects of ASX on the liver and immune system of TCP-treated animals depend upon improving the antioxidant status and relieving the inflammatory response, and thus it may be used as a promising therapeutic agent to provide superior hepato- and immunoprotection.  相似文献   
155.
Spatial variability and optimal sampling strategy of soil respiration   总被引:2,自引:0,他引:2  
Soil respiration is the second largest flux of carbon between terrestrial ecosystems and the atmosphere and is affecting climate sensitivity and vulnerability of the terrestrial carbon stock. Monitoring soil carbon dioxide efflux is a complex task, due to the high spatial and temporal variability of the fluxes. For this reason, more than 30 sampling points are required to attain reliable estimates of ecosystem soil respiration. However, the number of sampled points is often limited by labour, time and budget constraints. Stratified sampling is an alternative to random sampling as a method to reduce the number of sampling points when an effective proxy variable is available for the definition of the strata.  相似文献   
156.
Dietary supplements are commonly used by animals and humans and play key roles in diverse systems, such as the immune and reproductive systems, and in metabolism. Essential oils (EOs), which are natural substances, have potential for use in food supplementation; however, their effects on organisms remain to be elucidated. Here, we examine the effects of dietary Aloysia triphylla EO supplementation on zebrafish behavior, metabolism, stress response, and growth performance. We show that fish fed diets containing A. triphylla EO presented an anxiolytic response, with reduced exploratory activity and oxygen consumption; no changes were observed in neuroendocrine stress axis functioning and growth was not impaired. Taken together, these results suggest that the A. triphylla EO supplementation is a strong candidate for use in feed, since it ensures fish welfare (anxiolytic behavior) with decreased oxygen consumption. This makes it suitable for use in high-density production systems without causing damage to the neuroendocrine stress axis and without growth performance being impaired.  相似文献   
157.
158.
The present study focused on inhibitory activity of freshly extracted essential oils from three legal (THC < 0.2% w/v) hemp varieties (Carmagnola, Fibranova and Futura) on microbial growth. The effect of different sowing times on oil composition and biological activity was also evaluated. Essential oils were distilled and then characterized through the gas chromatography and gas chromatography-mass spectrometry. Thereafter, the oils were compared to standard reagents on a broad range inhibition of microbial growth via minimum inhibitory concentration (MIC) assay. Microbial strains were divided into three groups: i) Gram (+) bacteria, which regard to food-borne pathogens or gastrointestinal bacteria, ii) Gram (?) bacteria and iii) yeasts, both being involved in plant interactions. The results showed that essential oils of industrial hemp can significantly inhibit the microbial growth, to an extent depending on variety and sowing time. It can be concluded that essential oils of industrial hemp, especially those of Futura, may have interesting applications to control spoilage and food-borne pathogens and phytopathogens microorganisms.  相似文献   
159.
A new series of nortopsentin analogues, in which the imidazole ring of the natural product was replaced by thiazole and the indole unit bound to position 2 of the thiazole ring was substituted by a 7-azaindole moiety, was efficiently synthesized. Two of the new nortopsentin analogues showed good antiproliferative effect against the totality of the NCI full panel of human tumor cell lines (~60) having GI50 values ranging from low micromolar to nanomolar level. The mechanism of the antiproliferative effect of these derivatives, investigated on human hepatoma HepG2 cells, was pro-apoptotic, being associated with externalization of plasma membrane phosphatidylserine and mitochondrial dysfunction. Moreover, the compounds induced a concentration-dependent accumulation of cells in the subG0/G1phase, while confined viable cells in G2/M phase.  相似文献   
160.
Research and development of an innovative production system for hemp (Cannabis sativa L.) fibre for textile use requires the integration of multidisciplinary knowledge from cultivation technique to realization of end products. Research was carried out to study the effect of the agronomic factors cultivation year (2003–2004), genotype (Futura 75 and Tiborszallasi), plant population (120, 240 and 360 plants m−2) and harvesting time (beginning and full flowering) on fibre yield and quality in the whole hemp stem, and in the basal and apical stem portions separately. The study of separate stem portions was done to determine the effect on fibre quality of an innovative harvesting and processing system in which hemp stems are cut in two portions of approximately 1 m at harvest to enable processing on modern flax scutching lines.  相似文献   
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