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211.
Wheat grain contamination with toxigenic Fusarium spp. is of great economic concern to cereal producers and to the grain processing industry and is of great relevance for the quality and safety of the final products. In particular, the bread production chain can potentially be a vehicle for mycotoxin ingestion above the tolerable total daily intake. A quantitative polymerase chain reaction‐based analytical approach has been developed as a possible tool to estimate and control the risk of mycotoxins, particularly deoxynivalenol (DON). This DNA‐based analytical method has been applied to detect and quantify contamination levels of Fusarium graminearum and Fusarium culmorum in naturally infected wheat grain samples. The persistence of Fusarium contamination was also detected along the bread production chain in wholemeal, flour and bread. A significant correlation was found between Fusarium DNA and DON concentration in all samples.  相似文献   
212.
Thyroid hormones (THs) are key regulators of different biological processes. Their action involves genomic and non-genomic mechanisms, which together mediate the final effects of TH in target tissues. However, the proportion of the two processes and their contribution to the TH-mediated effects are still poorly understood. Skeletal muscle is a classical target tissue for TH, which regulates muscle strength and contraction, as well as energetic metabolism of myofibers. Here we address the different contribution of genomic and non-genomic action of TH in skeletal muscle cells by specifically silencing the deiodinase Dio2 or the β3-Integrin expression via CRISPR/Cas9 technology. We found that myoblast proliferation is inversely regulated by integrin signal and the D2-dependent TH activation. Similarly, inhibition of the nuclear receptor action reduced myoblast proliferation, confirming that genomic action of TH attenuates proliferative rates. Contrarily, genomic and non-genomic signals promote muscle differentiation and the regulation of the redox state. Taken together, our data reveal that integration of genomic and non-genomic signal pathways finely regulates skeletal muscle physiology. These findings not only contribute to the understanding of the mechanisms involved in TH modulation of muscle physiology but also add insight into the interplay between different mechanisms of action of TH in muscle cells.  相似文献   
213.
The interactions of Type I acid soluble collagen (Col) with both carbonate-free hydroxyapatite (HA1100) and carbonate-rich one (CHA) were investigated. The aim was to ascertain whether the increase of bone CO3 2− with ageing could relate to the disease known as osteoporosis. HA1100-Col and CHA-Col composites with various ratios were prepared and examined. Scanning electron microscopy and differential scanning calorimetry showed a stronger adhesion of the Col matrix to the granules of HA1100 than to those of CHA. FT-IR spectroscopy showed that with HA1100 both multiple hydrogen bonds of Col peptide –NH groups with HA PO4 3−, and electrochemical interactions between Col peptide –C=O groups and HA Ca2+ were present. In the presence of CO3 2−, the interactions between –NH and phosphate were diminished, and Ca2+ interacted more strongly with CO3 2− than with peptide –C=O, so causing a separation between the two components of the bone extra-cellular matrix. The results obtained strengthen the hypothesis that the substitution of PO4 3− ions by CO3 2− ions in the HA lattice might be a significant component of osteoporosis, although further investigation is needed.  相似文献   
214.
Fungal sepsis is one of the major problems in neonatal and pediatric care unit settings. The availability of new diagnostic techniques could allow medical practitioners to rapidly identify septic patients and to improve their outcome. The aim of this study was to evaluate the performance of the 1→3-β-d-glucan (BDG), individually and in comparison with the Candida mannan (CM) antigen, in ten preterm infants and five onco-haematological pediatric patients with Candida bloodstream infections already proven by positive culture. The serum levels of BDG were >80 pg/mL on the same day as a positive blood culture in all examined patients, while CM antigen was negative in the patients with C. parapsilosis fungemia and in one further case due to C. albicans. These results suggest that a regular monitoring of serum circulating antigens (i.e., 1→3-β-d-glucan) combined with other microbiological and clinical information, may allow earlier and accurate diagnosis. However, further studies are necessary to confirm its usefulness in routine clinical practice.  相似文献   
215.
New trans-platinum planar amines (TPAs) represent a family of platinum-based drugs with cytotoxicity equivalent to that of cisplatin, but with negligible cross-resistance. According to the substitution pattern around the metal center, distinct DNA adducts can be formed which yield various levels of cytotoxicity in cell lines. We compared the effects of leaving groups (Cl(-) versus formate or acetate) and amines (NH(3) versus aromatic heterocyclic planar systems) on the efficiency, kinetics, and mode of DNA platination. We show that the substitution of just a single amino group on the transplatin nucleus is optimal, with major effects on the kinetics of metal complex conversion into the reactive aquo species. Additionally, by monitoring TPA reactivity toward variable DNA structures, a lack of preference for double-stranded DNA in over single-stranded or G-quadruplex DNA was observed which is possibly related to steric effects of the planar amine groups. These properties can lead to a unique distribution of platination sites by TPA relative to the lead compound cisplatin, which may help to explain the unique cytotoxic profile of TPAs.  相似文献   
216.
MCrAlY coatings are usually adopted to improve the environmental resistance of Ni-based superalloy components of turbine engines against high-temperature oxidation and hot corrosion. In this work, CoNiCrAlYRe coatings were produced by atmospheric plasma spraying. The coatings exhibited relatively low oxygen content and porosity. X-ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy analyses revealed that the high-temperature exposure at 1383 K (1110 °C) promoted the growth of an oxide scale on the top surface being composed of a continuous and dense Al2O3 inner layer followed by an outer mixed layer (Cr2O3 and spinels). The oxide scale was mainly composed of Al2O3, while the formation of mixed oxides occurred at lesser extent. After high-temperature exposure, the formation of internal oxides in some areas reduced the inter-lamellar cohesion, so that a decrease in microhardness was found.  相似文献   
217.
Chemotherapy-induced neuropathy is a common, dose-dependent adverse effect of several antineoplastics, such as oxaliplatin (L-OHP). The aim of the present work was to evaluate the potential beneficial effects of 2-pentadecyl-2-oxazoline (PEA-OXA) in a murine model of oxaliplatin-induced peripheral neuropathy (OIPN). OIPN was induced by an intraperitoneally injection of L-OHP in rats on five consecutive days (D0–4) for a final cumulative dose of 10 mg/kg. PEA-OXA and ultramicronized palmitoylethanolamide (PEAum), both 10 mg/kg, were given orally 15–20 min prior (L-OHP) and sacrifice was made on day 25. Our results demonstrated that PEA-OXA, more than PEAum, reduced the development of hypersensitivity in rats; this was associated with the reduction in hyperactivation of glia cells and the increased production of proinflammatory cytokines in the dorsal horn of the spinal cord, accompanied by an upregulation of neurotrophic factors in the dorsal root ganglia (DRG). Moreover, we showed that PEA-OXA reduced L-OHP damage via a reduction in NF-κB pathway activation and a modulation of Nrf-2 pathways. Our findings identify PEA-OXA as a therapeutic target in chemotherapy-induced painful neuropathy, through the biomolecular signaling NF-κB/Nrf-2 axis, thanks to its abilities to counteract L-OHP damage. Therefore, we can consider PEA-OXA as a promising adjunct to chemotherapy to reduce chronic pain in patients.  相似文献   
218.
219.
An increasing number of applications in the chemical industry involve measuring nonconforming items, particularly in high-purity processes or high-yield processes. Dedicated monitoring tools such as the time-between-events (TBE) control charts have been developed for both discrete time (CCC-charts) and continuous time (tr-charts) for detecting any shifts in the process defect rate. However, most common performance metrics used in literature are not always appropriate and may not suffice to describe the efficiency of a monitoring system. The definition of conditional performance measures described in the literature is extended to TBE charts. These metrics are computed for Shewhart-type TBE charts with run rules and used to compare these charts at different aggregation levels.  相似文献   
220.
Micro-combined heat and power (CHP) systems are a key resource to meet the EUCO2 reduction agreed in the Kyoto Protocol. In the near future they are likely to spread significantly through applications in the residential and service sectors, since they can provide considerably higher primary energy efficiencies than plants generating electricity and heat separately. A 28 kWe natural gas, automotive-derived internal combustion engine CHP system was modeled with a view to comparing constant and variable speed operation modes. Besides their energy performances, the paper addresses the major factors involved in their economic evaluation and describes a method to assess their economic feasibility. Typical residential and service sector applications were chosen as test cases and the results discussed in terms of energy performances and of profitability. They showed that interesting savings can be obtained with respect to separate generation, and that they are higher for the household application in variable speed operating conditions. In fact the plant’s energy performance is greatly enhanced by the possibility, for any given power, to regulate the engine’s rotational speed. From the economic viewpoint, despite the higher initial cost of the variable speed concept, the system involves a shorter pay-back period and ensures greater profit.  相似文献   
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