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排序方式: 共有195条查询结果,搜索用时 9 毫秒
41.
Amparo Romero-Pic Marta G. Novelle Omar Al-Massadi Daniel Beiroa Marta Tojo Violeta Heras Francisco Ruiz-Pino Ana Senra Miguel Lpez Clemence Blouet Manuel Tena-Sempere Rubn Nogueiras Carlos Diguez 《International journal of molecular sciences》2022,23(6)
Weight gain is a hallmark of decreased estradiol (E2) levels because of menopause or following surgical ovariectomy (OVX) at younger ages. Of note, this weight gain tends to be around the abdomen, which is frequently associated with impaired metabolic homeostasis and greater cardiovascular risk in both rodents and humans. However, the molecular underpinnings and the neuronal basis for these effects remain to be elucidated. The aim of this study is to elucidate whether the kappa-opioid receptor (k-OR) system is involved in mediating body weight changes associated with E2 withdrawal. Here, we document that body weight gain induced by OVX occurs, at least partially, in a k-OR dependent manner, by modulation of energy expenditure independently of food intake as assessed in Oprk1−/−global KO mice. These effects were also observed following central pharmacological blockade of the k-OR system using the k-OR-selective antagonist PF-04455242 in wild type mice, in which we also observed a decrease in OVX-induced weight gain associated with increased UCP1 positive immunostaining in brown adipose tissue (BAT) and browning of white adipose tissue (WAT). Remarkably, the hypothalamic mTOR pathway plays an important role in regulating weight gain and adiposity in OVX mice. These findings will help to define new therapies to manage metabolic disorders associated with low/null E2 levels based on the modulation of central k-OR signaling. 相似文献
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Violeta Gulbiniene Greta Balciuniene Justina Petroniene Rita Viliene Irena Dumalakiene Ingrida Pilypiene Diana Ramasauskaite 《International journal of molecular sciences》2022,23(6)
Preterm premature rupture of membranes (PPROM) interrupts normal lung development, resulting in neonatal respiratory morbidity. Although post-PPROM risks have been researched, only a few studies have investigated noninvasively obtained amniotic fluid (AF) to predict neonatal outcomes. In this study, we aimed to determine whether epidermal growth factor (EGF) in vaginally-collected AF is a significant predictor of neonatal respiratory outcomes after PPROM. We analyzed EGF in vaginally-obtained AF from 145 women with PPROM at 22–34 weeks of gestation. The following neonatal outcomes were included: respiratory distress syndrome, surfactant need, duration and type of respiratory support, and bronchopulmonary dysplasia. We found that EGF concentration was associated with gestational age, and its medians were lower in neonates with respiratory morbidities than unaffected ones. EGF concentrations gradually declined, the lowest being in the most clinically ill patients. EGF < 35 pg/mL significantly predicted the odds of severe respiratory outcomes. EGF in noninvasively collected AF may be a reliable predictor for respiratory outcomes of preterm neonates with PPROM before 34 weeks of gestation. The results of our study may have implications for further research both in noninvasive amniotic fluid analysis and the management of patients after PPROM. 相似文献
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Violeta Purcar Dan Donescu Cristian Petcu Rafael Luque Duncan J. Macquarrie 《Catalysis communications》2009,10(4):395-400
Hybrid thin films containing palladium nanoparticles in different concentrations (0.5% and 1%) with and without nanoparticle stabiliser agent [mercaptopropyl trimethoxysilane, MPTMS] were prepared using a sol–gel process. Pd nanoparticles were found to be highly dispersed on the thin films with particles ranging from 7 to 10 nm. The catalytic properties of the thin films supported Pd nanoparticles were investigated in the Heck reaction of iodobenzene and methyl acrylate. Films containing Pd MNP (with and without MPTMS) gave quantitative conversion and complete selectivity to the targeted product (methyl cinnamate) in a short time of reaction (<15 min) under microwave irradiation. While Pd containing films without MPTMS were highly active and reusable after 3 runs, MPTMS containing films were found to be inactive after the first use. Such phenomenon was correlated to the steric hindrance round the Pd MNP due to the adsorption of species on the surface that render the catalysts inactive. 相似文献
46.
Violeta T. Pardio Maria D. Mariezcurrena Krzysztof N. Waliszewski Victor Sánchez Mariusz K. Janczur 《International Journal of Food Science & Technology》2009,44(12):2417-2423
The effects on the aroma compositions of ethanol extracts obtained by traditional and enzyme‐assisted methods from seven killing conditions used in vanilla pod curing were studied. Two procedures of vanilla pod killing consisted of either freezing pods at ?10 °C for 24 h or immersing pods in 80 °C water for 10 s each of three times with 30 s intervals resulted in the highest vanillin values in terms percentage of dry weight of the bean (2.84 and 2.96), 4‐hydroxybenzaldehyde (0.18 and 0.20), vanillyl alcohol (0.56 and 0.57) and vanillic acid (0.18 and 0.19 respectively) when traditional vanilla ethanol extraction was used. When this extract was aged for 3 months it showed improvement in flavour compounds. Enzyme‐assisted vanilla ethanol extraction showed a higher content of flavour compounds than traditional extract, for example vanillin 4.38% and 2.96% respectively. Only vanillic acid levels were improved after ageing of the enzyme‐assisted extracts. 相似文献
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Georgi Grancharov Violeta Mitova Stoitcho Shenkov Antonya Topliyska Ivan Gitsov Kolio Troev 《应用聚合物科学杂志》2007,105(2):302-308
This article describes a new approach for the recycling of microporous polyurethane elastomers by Tris(1‐methyl‐2‐chloroethyl) phosphate‐induced degradation. The phosphorus‐containing degradation products formed are transformed into reactive intermediates by reaction with propylene oxide and are used for the preparation of rigid polyurethane foams. These new phosphorus‐containing materials have higher density and better mechanical properties compared to the standard rigid polyurethane foams. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
49.
This work presents the γ irradiation (600–3500 kGy) and acid hydrolysis onto orange peel for hexavalent chromium removal. SEM, AFM, TGA-DSC, FTIR, and UV-Vis showed that γ rays enhance degradation and cleavage of orange peel cellulose polymeric chains, increasing the presence of reducing sugars after acid hydrolysis (0.1552 g/g biomass, 3500 kGy). Bioreduction kinetics of Cr(VI) using both solid and solubilized liquid fractions of γ irradiated biomass showed a direct correlation between the applied dose and Cr(VI) removal, reaching 100% of Cr(VI) reduction at pH 2 and 3500 kGy. Cr(VI) reduction is explained as a function of hydrolyzed reducing sugar oxidation. 相似文献
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