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The water-soluble plant polyphenols rutin, (+)-catechin, and (–)-epigallocatechin gallate were each found to be efficient quenchers for the triplet-excited state of riboflavin in aqueous solution using nano-second laser flash photolysis. The deactivation followed second-order kinetics with rates close to the diffusion control: (–)-epigallocatechin gallate (1.70±0.2×109 l mol–1 s–1), (+)-catechin (1.44±0.04×109 l mol–1 s–1), and rutin (9.7±0.2×108 l mol–1 s–1) at 25 °C and pH = 6.8. No synergetic effects for mixtures of the phenolic compounds were found. Hydrogen atom transfer is calculated to be more exergonic than electron transfer, suggesting the hydrogen atom transfer mechanism to be operative. The efficient deactivation by the plant polyphenols makes this type of compounds of importance as protectors against light-induced oxidation in flavored milk-based beverages.  相似文献   
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A standard fresh pasta formulation (STD, the control sample) was modified by introducing soy and carrot ingredients both in dry and in liquid forms (soy and carrot flour and soy milk and carrot juice) to obtain eight nutritionally enriched fresh pasta samples with different formulations. The effect of formulation on selected physicochemical properties and water status of fresh pasta were studied. Colour, texture (force at rupture and extensibility), and cooking loss were found significantly affected by the formulation. Soy and carrot decreased the force at rupture and extensibility of fresh pasta and increased the solids loss during cooking. Improper gluten network development due to either a steric hindrance of soy and carrot solids or improper water availability for gluten hydration due to different water–solid interaction developed were hypothesized. Soy and carrot ingredients significantly altered the water dynamics in the pasta matrix at different space-time levels (macroscopic, moisture content and water activity; macromolecular, frozen water content; molecular, proton nuclear magnetic resonance relaxometry) of fresh pasta in a manner dependent upon the physical state of the added ingredient. Soy flour increased both the frozen water content and the overall proton mobility (1H FID, 1H T 1 and T 2) of fresh pasta while these parameters did not markedly differed from STD when soy milk was used. The presence of both carrot flour and carrot juice decreased significantly the frozen water content of fresh pasta but, at a molecular level, carrot flour altered the proton molecular mobility, while carrot juice did not.  相似文献   
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The centromere is the chromosomal locus essential for proper chromosome segregation. While the centromeric function is well conserved and epigenetically specified, centromeric DNA sequences are typically composed of satellite DNA and represent the most rapidly evolving sequences in eukaryotic genomes. The presence of satellite sequences at centromeres hampered the comprehensive molecular analysis of these enigmatic loci. The discovery of functional centromeres completely devoid of satellite repetitions and fixed in some animal and plant species represented a turning point in centromere biology, definitively proving the epigenetic nature of the centromere. The first satellite-free centromere, fixed in a vertebrate species, was discovered in the horse. Later, an extraordinary number of satellite-free neocentromeres had been discovered in other species of the genus Equus, which remains the only mammalian genus with numerous satellite-free centromeres described thus far. These neocentromeres arose recently during evolution and are caught in a stage of incomplete maturation. Their presence made the equids a unique model for investigating, at molecular level, the minimal requirements for centromere seeding and evolution. This model system provided new insights on how centromeres are established and transmitted to the progeny and on the role of satellite DNA in different aspects of centromere biology.  相似文献   
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The autonomic nervous system (ANS) and the immune system are deeply interrelated. The ANS regulates both innate and adaptive immunity through the sympathetic and parasympathetic branches, and an imbalance in this system can determine an altered inflammatory response as typically observed in chronic conditions such as systemic autoimmune diseases. Rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis all show a dysfunction of the ANS that is mutually related to the increase in inflammation and cardiovascular risk. Moreover, an interaction between ANS and the gut microbiota has direct effects on inflammation homeostasis. Recently vagal stimulation techniques have emerged as an unprecedented possibility to reduce ANS dysfunction, especially in chronic diseases characterized by pain and a decreased quality of life as well as in chronic inflammation.  相似文献   
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In the search for non-chemical and green methods to counteract the bacterial contamination of foods, the use of natural substances with antimicrobial properties and light irradiation at proper light waves has been extensively investigated. In particular, the combination of both techniques, called photodynamic inactivation (PDI), is based on the fact that some natural substances act as photosensitizers, i.e., produce bioactive effects under irradiation. Notably, curcumin is a potent natural antibacterial and effective photosensitizer that is able to induce photodynamic activation in the visible light range (specifically for blue light). Some practical applications have been investigated with particular reference to food preservation from bacterial contaminants.  相似文献   
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In severe COVID-19, which is characterized by blood clots and neutrophil-platelet aggregates in the circulating blood and different tissues, an increased incidence of cardiovascular complications and venous thrombotic events has been reported. The inflammatory storm that characterizes severe infections may act as a driver capable of profoundly disrupting the complex interplay between platelets, endothelium, and leukocytes, thus contributing to the definition of COVID-19-associated coagulopathy. In this frame, P-selectin represents a key molecule expressed on endothelial cells and on activated platelets, and contributes to endothelial activation, leucocyte recruitment, rolling, and tissue migration. Briefly, we describe the current state of knowledge about P-selectin involvement in COVID-19 pathogenesis, its possible use as a severity marker and as a target for host-directed therapeutic intervention.  相似文献   
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Tumor progression is a key aspect in oncology. Not even the overexpression of a powerful oncogenic stimulus such as platelet derived growth factor-B (PDGF-B) is sufficient per se to confer full malignancy to cells. In previous studies we showed that neural progenitors overexpressing PDGF-B need to undergo progression to acquire the capability to give rise to secondary tumor following transplant. By comparing the expression profile of PDGF-expressing cells before and after progression, we found that progressed tumors consistently downregulate the expression of the antiproliferative gene Btg2. We therefore tested whether the downregulation of Btg2 is sufficient and necessary for glioma progression with loss and gain of function experiments. Our results show that downregulation of Btg2 is not sufficient but is necessary for tumor progression since the re-introduction of Btg2 in fully progressed tumors dramatically impairs their gliomagenic potential. These results suggest an important role of Btg2 in glioma progression. Accordingly with this view, the analysis of public datasets of human gliomas showed that reduced level of Btg2 expression correlates with a significantly worse prognosis.  相似文献   
20.
Hydrothermal carbonization of sewage sludge was carried out with the aim to evaluate the influence of process severity and initial solid content. Response surface methodology was applied to model yield and C yield responses. Enhanced dewaterability performance was recorded under mild processing conditions. The treatment promoted concentration and immobilization of Pb, Cd, Ni, Zn, and Cu. Variation of the solid content showed a stronger influence than severity on average yield and C yield. Higher heating values (HHVs) and energy retention efficiencies (EREs) of hydrochars obtained at the lowest solid content displayed the lowest values. Hence, the energy requirements of a first dewatering step should be compared with the related improvement in terms of HHV and ERE when sludge is used as feedstock.  相似文献   
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