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11.
Scope: Deoxynivalenol (DON) and fumonisins (FB) are the most frequently encountered mycotoxins produced by Fusarium species and most commonly co‐occur in animal diets. These mycotoxins were studied for their toxicity in piglets on several parameters including plasma biochemistry, organ histopathology and immune response. Methods and results: Twenty‐four 5‐wk‐old animals were randomly assigned to four different groups, receiving separate diets for 5 wk, a control diet, a diet contaminated with either DON (3 mg/kg) or FB (6 mg/kg) or both toxins. At days 4 and 16 of the trial, the animals were subcutaneously immunized with ovalbumin to assess their specific immune response. The different diets did not affect animal performance and had minimal effect on hematological and biochemical blood parameters. By contrast, DON and FB induced histopathological lesions in the liver, the lungs and the kidneys of exposed animals. The liver was significantly more affected when the two mycotoxins were present simultaneously. The contaminated diets also altered the specific immune response upon vaccination as measured by reduced anti‐ovalbumin IgG level in the plasma and reduced lymphocyte proliferation upon antigenic stimulation. Because cytokines play a key role in immunity, the expression levels of IL‐8, IL‐1β, IL‐6 and macrophage inflammatory protein‐1β were measured by RT‐PCR at the end of the experiment. The expression of these four cytokines was significantly decreased in the spleen of piglets exposed to multi‐contaminated diet. Conclusion: Taken together, our data indicate that ingestion of multi‐contaminated diet induces greater histopathological lesions and higher immune suppression than ingestion of mono‐contaminated diets.  相似文献   
12.
The ability of bacterial species to colonize and infect host organisms is critically dependent upon their capacity to adhere to cellular surfaces of the host. Adherence to cell surfaces is known to be essential for the activation and delivery of certain virulence factors, but can also directly affect host cell signaling to aid bacterial spread and survival. In this review we will discuss the recent advances in the field of bacterial adhesion, how we are beginning to unravel the effects adhesins have on host cell signaling, and how these changes aid the bacteria in terms of their survival and evasion of immune responses. Finally, we will highlight how the exploitation of bacterial adhesins may provide new therapeutic avenues for the treatment of a wide range of bacterial infections.  相似文献   
13.
Coupled transfers of aroma compounds and water vapour were investigated by varying the relative humidity gradient of storage (50% or 90%) of two paper packaging at 25 °C. These papers differed in their coating surface: both were identically impregnated then supercalendered, and only one was twice coated on both sides with a synthetic barrier substance. Permeability and solubility coefficients were determined. The coating treatment was more effective to decrease the permeabilities of water vapour and ethyl ester than the effect of RH. On the contrary, the RH modified the water content of the treated papers and affected more strongly their permeability and solubility to cis-3-hexenol and benzaldehyde. The cis-3-hexenol transfer through the non-coated paper and the benzaldehyde transfer through the coated paper decreased due to a probable competition with sorbed water although it increases for the cis-3-hexenol of a plasticisation phenomenon.  相似文献   
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The feasibility of low-temperature (7 °C) anaerobic digestion for the treatment of a trichloroethylene (TCE) contaminated wastewater was investigated. Two expanded granular sludge bed (EGSB) bioreactors (R1 and R2) were employed for the mineralisation of a synthetic volatile fatty acid based wastewater at an initial organic loading rate (OLR) of 3 kg COD m−3 d−1, and an operating temperature of 15 °C. Successive reductions in OLR to 0.75 kg COD m−3 d−1, and operational temperature to 7 °C, resulted in stable bioreactor operation by day 417, with COD removal efficiency and biogas CH4 content ≥74%, for both bioreactors. Subsequently, the influent to R1 was supplemented with increasing concentrations (10, 20, 30 mg l−1) of TCE, while R2 acted as a control. At an influent TCE concentration of 30 mg l−1, although phase average TCE removal rates of 79% were recorded, a sustained decrease in R1 performance was observed, with COD removal of 6%, and % biogas CH4 of 3% recorded on days 595 and 607, respectively. Specific methanogenic activity (SMA) assays identified a general shift from acetate- to hydrogen-mediated methanogenesis in both R1 and R2 biomass, while toxicity assays confirmed an increased sensitivity of the acetoclastic community in R1 to TCE and dichloroethylene (DCE), which contributed to acetate accumulation. Quantitative Polymerase Chain Reaction (qPCR) analysis of the methanogenic community confirmed the dominance of hydrogenotrophic methanogens in both R1 and R2, representing 71-89% of the total methanogenic population, however acetoclastic Methanosaeta were the dominant organisms, based on 16S rRNA gene clone library analysis of reactor biomass. The greatest change in the bacterial community, as demonstrated by UPGMA analysis of DGGE banding profiles, was observed in R1 biomass between days 417 and 609, although 88% similarity was retained between these sampling points.  相似文献   
16.
The authors investigated whether intensive musical experience leads to enhancements in executive processing, as has been shown for bilingualism. Young adults who were bilinguals, musical performers (instrumentalists or vocalists), or neither completed 3 cognitive measures and 2 executive function tasks based on conflict. Both executive function tasks included control conditions that assessed performance in the absence of conflict. All participants performed equivalently for the cognitive measures and the control conditions of the executive function tasks, but performance diverged in the conflict conditions. In a version of the Simon task involving spatial conflict between a target cue and its position, bilinguals and musicians outperformed monolinguals, replicating earlier research with bilinguals. In a version of the Stroop task involving auditory and linguistic conflict between a word and its pitch, the musicians performed better than the other participants. Instrumentalists and vocalists did not differ on any measure. Results demonstrate that extended musical experience enhances executive control on a nonverbal spatial task, as previously shown for bilingualism, but also enhances control in a more specialized auditory task, although the effect of bilingualism did not extend to that domain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Polymerase chain reaction (PCR)-enzyme linked immunosorbent assays (ELISAs) targeting either the 35S promoter or the Bt176 specific junction sequence were developed to screen for the presence of genetically modified organisms (GMOs) and specifically detect Bt176 maize in flours and starches. Two additional PCR-ELISA assays were developed to validate the results: one, based on the detection of the maize alcohol dehydrogenase 1 promoter specifically detected the presence of maize, and the other, based on the detection of a conserved sequence of plants ( 26S ribosomal RNA gene), validated the extracted DNA amplification. The PCR-ELISA assays developed here were highly specific and found to be as sensitive as the reference Southern hybridisation assay. The PCR-ELISA tests were at least 6 times more sensitive than gel electrophoresis and allowed 0.1% GMOs to be detected in Bt176, Bt11, Mon810 maize and Roundup Ready soybean. The PCR-ELISA tests are a method of choice for GMO screening and identifying Bt176 maize in flours and native starches. They may offer a cheaper alternative to the expensive real-time PCR assays and may be useful in laboratory GMO monitoring.  相似文献   
19.
Embedded devices using highly integrated chips must cope with conflicting constraints, while executing computationally demanding applications under limited energy storage. Automatic control and feedback loops appear to be an effective solution to simultaneously accommodate for performance uncertainties due to the tiny scale gates variability, varying and poorly predictable computing demands and limited energy storage constraints. This paper presents the example of an embedded video decoder controlled by several feedback loops to carry out the trade-off between decoding quality and energy consumption, exploiting the frequency and voltage scaling capabilities of the chip. The inner loop controls the dynamic voltage and frequency scaling through a fast predictive control strategy. The outer loop computes the scheduling set-points needed by the inner loop to process frames decoding. The feedback loops have been implemented on a stock PC and experimental results are provided.  相似文献   
20.
Using an in vivo manipulation, this study examined whether alcohol outcome expectancies (AOEs) vary across environmental settings. Two hundred twenty-one undergraduates were randomly assigned to 1 of 4 conditions in which environmental context (an on-campus bar vs. a laboratory) and instructed phase of intoxication ("just enough to begin to feel intoxicated" vs. "too much to drink") were manipulated. AOEs were assessed with a revised version of the Effects of Alcohol Scale (L. Southwick, C. Steele, A. Marlatt, & M. Lindell, 1981). Compared with participants tested in the laboratory, individuals exposed to the on-campus bar expected greater alcohol-related stimulation/perceived dominance and pleasurable disinhibition. Women expected more behavioral impairment during the latter stage of intoxication. These findings highlight the importance of ecologically valid research in this area, as well as cue-exposure assessment and treatment approaches. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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