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11.
Gabriele Mocciaro Simona DAmore Benjamin Jenkins Richard Kay Antonio Murgia Luis Vicente Herrera-Marcos Stefanie Neun Alice P. Sowton Zoe Hall Susana Alejandra Palma-Duran Giuseppe Palasciano Frank Reimann Andrew Murray Patrizia Suppressa Carlo Sabb Antonio Moschetta Albert Koulman Julian L. Griffin Michele Vacca 《International journal of molecular sciences》2022,23(12)
The metabolic syndrome (MetS) is a cluster of cardiovascular risk factors characterised by central obesity, atherogenic dyslipidaemia, and changes in the circulating lipidome; the underlying mechanisms that lead to this lipid remodelling have only been partially elucidated. This study used an integrated “omics” approach (untargeted whole serum lipidomics, targeted proteomics, and lipoprotein lipidomics) to study lipoprotein remodelling and HDL composition in subjects with central obesity diagnosed with MetS (vs. controls). Compared with healthy subjects, MetS patients showed higher free fatty acids, diglycerides, phosphatidylcholines, and triglycerides, particularly those enriched in products of de novo lipogenesis. On the other hand, the “lysophosphatidylcholines to phosphatidylcholines” and “cholesteryl ester to free cholesterol” ratios were reduced, pointing to a lower activity of lecithin cholesterol acyltransferase (LCAT) in MetS; LCAT activity (directly measured and predicted by lipidomic ratios) was positively correlated with high-density lipoprotein cholesterol (HDL-C) and negatively correlated with body mass index (BMI) and insulin resistance. Moreover, many phosphatidylcholines and sphingomyelins were significantly lower in the HDL of MetS patients and strongly correlated with BMI and clinical metabolic parameters. These results suggest that MetS is associated with an impairment of phospholipid metabolism in HDL, partially led by LCAT, and associated with obesity and underlying insulin resistance. This study proposes a candidate strategy to use integrated “omics” approaches to gain mechanistic insights into lipoprotein remodelling, thus deepening the knowledge regarding the molecular basis of the association between MetS and atherosclerosis. 相似文献
12.
Influence of ethanol/water ratio in ultrasound and high‐pressure/high‐temperature phenolic compound extraction from agri‐food waste 下载免费PDF全文
Marco Paini Alessandro A. Casazza Bahar Aliakbarian Patrizia Perego Arianna Binello Giancarlo Cravotto 《International Journal of Food Science & Technology》2016,51(2):349-358
The valorisation and management of agri‐food waste are currently hot investigation topics which probe the recovery of valuable compounds, such as polyphenols. In this study, high‐pressure/high‐temperature extraction (HPTE) and ultrasound‐assisted extraction (UAE) have been used to study the recovery of phenolic compounds from grape marc and olive pomace in hydroalcoholic solutions. The main phenolic compounds in both extracts were identified by HPLC‐DAD. Besides extraction yield (total polyphenol and flavonoid content) and the antiradical power, polyphenol degradation under HPTE and UAE has also been studied. HPTE with ethanol 75% gave higher phenolic extraction yields: 73.8 ± 1.4 mg of gallic acid equivalents per gram of dried matter and 60.0 mg of caffeic acid equivalents per gram of dried matter for grape marc and olive pomace, respectively. In this study, the efficient combination of ethanol/water mixture with HPTE or UAE has been used to enhance the recovery of phenolic compounds from grape marc and olive pomace. HPLC‐DAD showed that UAE prevents phenolic species degradation damage because of its milder operative conditions. 相似文献
13.
Ultrastructural and developmental toxicity of potato and tomato leaf extracts to beet armyworm,Spodoptera exigua (lepidoptera: noctuidae) 下载免费PDF全文
Zbigniew Adamski Katarzyna Radtke Agnieszka Kopiczko Szymon Chowański Paweł Marciniak Monika Szymczak Marta Spochacz Patrizia Falabella Filomena Lelario Laura Scrano Sabino A. Bufo 《Microscopy research and technique》2016,79(10):948-958
Beet Armyworm, Spodoptera exigua is a herbivorous moth and a serious pest of many economically important plants, which are used as food sources. Because of rigorous standards of food quality, usage of synthetic insecticides in crop protection, against pests, is limited. Solanaceae plant extracts may be a relatively cheap source of efficient natural insecticides that can limit usage of synthetic substances. Their biological activity is not fully known. In particular, ultrastructural studies, using transmission electron microscopy, are not usual. In the present article we describe the effects of sublethal concentrations of tomato and potato leaf extracts against S. exigua. Acute lethal effects were not observed. Both extracts exerted similar effects within midgut and fat body cells. Midgut cells were not significantly altered while fat body cells showed prominent swelling of nuclear envelope and endoplasmic reticulum, vacuolization of mitochondria and fusion of fat droplets. These changes were much more intensive within groups exposed to potato than tomato extracts at highest concentration at least. Light microscopy was used to observe and document developmental alterations of S. exigua exposed to potato and tomato leaf extracts. Potato leaf extracts significantly decreased hatching success and caused morphological malformations of imagoes. Among them, malformations of wings were the most prominent. Interestingly, these effects were not observed within populations exposed to tomato extracts at highest concentration at least. 相似文献
14.
Gianluigi De Falco Mario Commodo Carmela Bonavolontà Giovanni Piero Pepe Patrizia Minutolo Andrea D’Anna 《Combustion and Flame》2014
Optical and electrical properties of carbonaceous particles produced in laboratory scale, premixed ethylene/air flames are obtained. Light absorption and Raman spectroscopy show that the change in particle nanostructure follows a graphitization trajectory as the flame richness increases. The optical band gap decreases and the size of the aromatic network in the particle increases, while the interlayer spacing between parallel layers decreases. The electrical conductivity of the materials increases by increasing flame richness in agreement to the graphitization trajectory. A non-ohmic behavior has been found and explained in terms of electron tunneling in a percolative network. Our results show that the electrical properties of flame formed carbon nanoparticles are strongly dependent on their nanostructure, and hence they have to be used carefully for the determination of particle concentration with conductometric sensors. Moreover, the dependence of the electrical properties of combustion formed particles might be useful for the development of cheap sensors for the selective detection of different classes of combustion aerosols. 相似文献
15.
Patrizia Restani Francesca Uberti Roberta Danzi Cinzia Ballabio Francesco Pavanello Chiara Tarantino 《Food chemistry》2012
The possible presence of allergenic residues in wines treated with one of the potassium caseinates used as fining agents has been investigated. 相似文献
16.
17.
Most studies on surface-initiated controlled polymerizations for the synthesis of polymeric covalent organic-inorganic hybrid materials focus on chemical methods requiring specific modifications of the inorganic substrate. Few mechanistically-aware approaches have been undertaken towards exploiting the reactivity of defects induced by physical techniques such as ionizing radiations or UV–Vis light. Within this framework, we take grafted polymerization of styrene from γ-irradiated silica as a mechanistic testing ground where para- and diamagnetic silica defects are present, and polymerization proceeds through both radical and cationic mechanisms, resulting in a bimodal molecular weight distribution. We show that these mechanistic intricacies can be sorted out by resorting to the chemical arsenal developed in the last decades for controlled polymerizations. Specifically, we obtained a silica-polystyrene grafted material by cationic grafting from at 30 °C, a unimodal molecular weight distribution, and a relatively high molecular weight (Mn = 7.4 kDa) with a PDI of 1.68. 相似文献
18.
伽利略EPTS中原子钟频率稳定度与噪声类型分析 总被引:3,自引:0,他引:3
本文对伽利略系统实验精确授时中心(EPTS)中四台原子钟的主要特性进行了分析.首先基于原子钟的信号模型和时域上的实验测量数据,用Allan方差对各原子钟的频率稳定度进行了计算与分析.其次运用最小二乘算法对短期和长期的时域稳定度数据进行线性拟合,根据拟合斜率鉴别了影响EPTS中各原子钟的主要噪声类型.实验结果表明,EPTS中具有高短期稳定度的氢原子钟和三台高长期稳定度的铯原子钟满足在GSTB-V1阶段产生实验伽利略系统时间(EGST)的设计要求. 相似文献
19.
Mariachiara Zuccarini Patricia Giuliani Valentina Di Liberto Monica Frinchi Francesco Caciagli Vanni Caruso Renata Ciccarelli Giuseppa Mud Patrizia Di Iorio 《International journal of molecular sciences》2022,23(3)
Over the last decade, several compounds have been identified for the treatment of obesity. However, due to the complexity of the disease, many pharmacological interventions have raised concerns about their efficacy and safety. Therefore, it is important to discover new factors involved in the induction/progression of obesity. Adipose stromal/stem cells (ASCs), which are mostly isolated from subcutaneous adipose tissue, are the primary cells contributing to the expansion of fat mass. Like other cells, ASCs release nanoparticles known as extracellular vesicles (EVs), which are being actively studied for their potential applications in a variety of diseases. Here, we focused on the importance of the contribution of ASC-derived EVs in the regulation of metabolic processes. In addition, we outlined the advantages/disadvantages of the use of EVs as potential next-generation anti-obesity agents. 相似文献
20.
Ya-Fei Zhao Wen-Jing Ren Ying Zhang Jin-Rong He Hai-Yan Yin Yang Liao Patrizia Rubini Jan M. Deussing Alexei Verkhratsky Zeng-Qiang Yuan Peter Illes Yong Tang 《International journal of molecular sciences》2022,23(3)
Extracellular adenosine 5′-triphosphate (ATP) in the brain is suggested to be an etiological factor of major depressive disorder (MDD). It has been assumed that stress-released ATP stimulates P2X7 receptors (Rs) at the microglia, thereby causing neuroinflammation; however, other central nervous system (CNS) cell types such as astrocytes also possess P2X7Rs. In order to elucidate the possible involvement of the MDD-relevant hippocampal astrocytes in the development of a depressive-like state, we used various behavioral tests (tail suspension test [TST], forced swim test [FST], restraint stress, inescapable foot shock, unpredictable chronic mild stress [UCMS]), as well as fluorescence immunohistochemistry, and patch-clamp electrophysiology in wild-type (WT) and genetically manipulated rodents. The TST and FST resulted in learned helplessness manifested as a prolongation of the immobility time, while inescapable foot shock caused lower sucrose consumption as a sign of anhedonia. We confirmed the participation of P2X7Rs in the development of the depressive-like behaviors in all forms of acute (TST, FST, foot shock) and chronic stress (UCMS) in the rodent models used. Further, pharmacological agonists and antagonists acted in a different manner in rats and mice due to their diverse potencies at the respective receptor orthologs. In hippocampal slices of mice and rats, only foot shock increased the current responses to locally applied dibenzoyl-ATP (Bz-ATP) in CA1 astrocytes; in contrast, TST and restraint depressed these responses. Following stressful stimuli, immunohistochemistry demonstrated an increased co-localization of P2X7Rs with a microglial marker, but no change in co-localization with an astroglial marker. Pharmacological damage to the microglia and astroglia has proven the significance of the microglia for mediating all types of depression-like behavioral reactions, while the astroglia participated only in reactions induced by strong stressors, such as foot shock. Because, in addition to acute stressors, their chronic counterparts induce a depressive-like state in rodents via P2X7R activation, we suggest that our data may have relevance for the etiology of MDD in humans. 相似文献