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1.
Excessive energy intake may evoke complex biochemical processes characterized by inflammation, oxidative stress, and impairment of mitochondrial function that represent the main factors underlying noncommunicable diseases. Because cow milk is widely used for human nutrition and in food industry processing, the nutritional quality of milk is of special interest with respect to human health. In our study, we analyzed milk produced by dairy cows fed a diet characterized by a high forage:concentrate ratio (high forage milk, HFM). In view of the low n-6:n-3 ratio and high content of conjugated linoleic acid of HFM, we studied the effects of this milk on lipid metabolism, inflammation, mitochondrial function, and oxidative stress in a rat model. To this end, we supplemented for 4 wk the diet of male Wistar rats with HFM and with an isocaloric amount (82 kJ, 22 mL/d) of milk obtained from cows fed a diet with low forage:concentrate ratio, and analyzed the metabolic parameters of the animals. Our results indicate that HFM may positively affect lipid metabolism, leptin:adiponectin ratio, inflammation, mitochondrial function, and oxidative stress, providing the first evidence of the beneficial effects of HFM on rat metabolism.  相似文献   
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Under the hypothesis that cardioprotective agents might benefit from synergism between antiarrhythmic activity and antioxidant properties, a small series of mexiletine analogues were coupled with the 2,2,5,5-tetramethylpyrroline moiety, known for its antioxidant effect, in order to obtain dual-acting drugs potentially useful in the protection of the heart against post-ischemic reperfusion injury. The pyrroline derivatives reported herein were found to be more potent as antiarrhythmic agents than mexiletine and displayed antioxidant activity. The most interesting tetramethylpyrroline congener, a tert-butyl-substituted analogue, was at least 100 times more active as an antiarrhythmic than mexiletine.  相似文献   
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Cardiac connexins (Cxs) are proteins responsible for proper heart function. They form gap junctions that mediate electrical and chemical signalling throughout the cardiac system, and thus enable a synchronized contraction. Connexins can also individually participate in many signal transduction pathways, interacting with intracellular proteins at various cellular compartments. Altered connexin expression and localization have been described in diseased myocardium and the aim of this study is to assess the involvement of Cx43, Cx26, and some related molecules in ponatinib-induced cardiac toxicity. Ponatinib is a new multi-tyrosine kinase inhibitor that has been successfully used against human malignancies, but its cardiotoxicity remains worrisome. Therefore, understanding its signaling mechanism is important to adopt potential anti cardiac damage strategies. Our experiments were performed on hearts from male and female mice treated with ponatinib and with ponatinib plus siRNA-Notch1 by using immunofluorescence, Western blotting, and proteomic analyses. The altered cardiac function and the change in Cxs expression observed in mice after ponatinib treatment, were results dependent on the Notch1 pathway and sex. Females showed a lower susceptibility to ponatinib than males. The downmodulation of cardiac Cx43, Cx26 and miR-122, high pS368-Cx43 phosphorylation, cell viability and survival activation could represent some of the female adaptative/compensatory reactions to ponatinib cardiotoxicity.  相似文献   
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The EU‐funded project UAN (Underwater Acoustic Network) was aimed at conceiving, developing, and testing at sea an innovative and operational concept for integrating underwater and above‐water sensors in a unique communication system to protect offshore and coastline critical infrastructures. This work gives details on the underwater part of the project. It introduces a set of original security features and gives details on the integration of autonomous underwater vehicles (AUVs) as mobile nodes of the network and as surveillance assets, acoustically controlled by the command and control center to respond against intrusions. Field results are given of the final UAN project sea trial, UAN11, held in May 2011 in Norway. During the experimental activities, a UAN composed of four fixed nodes, two AUVs, and one mobile node mounted on the supporting research vessel was operated continuously and integrated into a global protection system. In this article, the communication performance of the network is reported in terms of round‐trip time, packet loss, and average delivery ratio. The major results of the experiment can be thus summarized: the implemented network structure was successful in continuously operating over five days with nodes seamlessly entering and exiting the network; the performance of the network varied greatly with fluctuations in the acoustic channel; the addition of security features induced a minor degradation in network performance with respect to channel variation; the AUVs were successfully controlled from a remote station through acoustic signals routed by the network. © 2013 Wiley Periodicals, Inc.  相似文献   
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Ricco G  Tomei MC  Ramadori R  Laera G 《Water research》2004,38(8):2103-2110
The toxicity of four xenobiotic compounds 3,5-dichlorophenol, formaldehyde, 4-nitrophenol and dichloromethane, representative of industrial wastewater contaminants was evaluated by a simple respirometric procedure set up on the basis of OECD Method 209 and by the Microtox bioassay. Very good reproducibility was observed for both methods, the variation coefficients being in the range of 2-10% for the respirometric procedure and 6-15% for Microtox, values that can be considered very good for a biological method. Comparison of EC(50) data obtained with the two methods shows that in both cases 3,5-dichlorophenol is more toxic than other compounds investigated and dichloromethane has a very low toxicity value. Intermediate EC(50) values were found for the two other chemicals, formaldehyde and 4-nitrophenol. Moreover, the Microtox EC(50) values are generally lower (except for dichloromethane) than the respirometric ones: these differences could be explained by the fact that the Microtox method uses a pure culture of marine species and, therefore, should not necessarily be expected to behave like a community of activated sludge bacteria. In conclusion, both methods can be usefully applied for toxicity detection in wastewater treatment plants but it is advisable to take into account that Microtox is more sensitive than respirometry in estimating the acute toxicity effect on the biomass operating in the plant.  相似文献   
9.
We describe a novel noninvasive optical technique to monitor the refractive-index variation in an epoxy-based resin that is due to the polymerization process. This kind of resin is widely used in polymer matrix composites. It is well known that the process of fabricating a thermoset-based composite involves mass and heat transfer coupled with irreversible chemical reactions that induce physical changes. To improve the quality and the reliability of these materials, monitoring the cure and optimization of the manufacturing process are of key importance. We discuss the basic operating principles of an optical system based on angle deflection measurements and present typical cure-monitoring results obtained from optical characterization. The method provides a flexible, high-sensitivity, material-independent, low-cost, noninvasive tool for monitoring real-time refractive-index variation.  相似文献   
10.
The Regulatory Emotional Self-Efficacy (RESE) scale was developed to assess perceived self-efficacy in managing negative (NEG) and in expressing positive (POS) affect (G. V. Caprara & M. Gerbino, 2001). In this study of young adults, the factorial structure of the RESE scale was found to be similar in Italy, the United States, and Bolivia. In addition to a factor for POS, NEG was represented by a second-order factor of 2 different negative affects: despondency-distress (DES) and anger-irritation (ANG). Overall, there was partial invariance at both metric and scalar levels across gender and countries. Discriminant and convergent validity of the RESE scale was further examined in the Italian sample. Stronger patterns of association of POS with prosocial behavior, of ANG with low aggressive behavior problems and irritability, and of DES with low anxiety/depressive problems and shyness and high self-esteem were found. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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