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991.
Eleonora Di Gregorio Barbara Borroni Elisa Giorgio Daniela Lacerenza Marta Ferrero Nicola Lo Buono Neftj Ragusa Cecilia Mancini Marion Gaussen Alessandro Calcia Nico Mitro Eriola Hoxha Isabella Mura Domenico A. Coviello Young-Ah Moon Christelle Tesson Giovanna Vaula Philippe Couarch Laura Orsi Eleonora Duregon Mauro Giulio Papotti Jean-François Deleuze Jean Imbert Chiara Costanzi Alessandro Padovani Paola Giunti Marcel Maillet-Vioud Alexandra Durr Alexis Brice Filippo Tempia Ada Funaro Loredana Boccone Donatella Caruso Giovanni Stevanin Alfredo Brusco 《American journal of human genetics》2014
992.
High Insulin‐Induced Down‐Regulation of Erk‐1/IGF‐1R/FGFR‐1 Signaling Is Required for Oxidative Stress‐Mediated Apoptosis of Adipose‐Derived Stem Cells
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993.
Supercritical CO2 Induces Marked Changes in Membrane Phospholipids Composition in Escherichia coli K12 总被引:1,自引:0,他引:1
Sabrina Tamburini Andrea Anesi Giovanna Ferrentino Sara Spilimbergo Graziano Guella Olivier Jousson 《The Journal of membrane biology》2014,247(6):469-477
Supercritical carbon dioxide (SC-CO2) treatment is one of the most promising alternative techniques for pasteurization of both liquid and solid food products. The inhibitory effect of SC-CO2 on bacterial growth has been investigated in different species, but the precise mechanism of action remains unknown. Membrane permeabilization has been proposed to be the first event in SC-CO2-mediated inactivation. Flow cytometry, high performance liquid chromatography–electrospray ionization–mass spectrometry and NMR analyses were performed to investigate the effect of SC-CO2 treatment on membrane lipid profile and membrane permeability in Escherichia coli K12. After 15 min of SC-CO2 treatment at 120 bar and 35 °C, the majority of bacterial cells dissipated their membrane potential (95 %) and lost membrane integrity, as 81 % become partially permeabilized and 18 % fully permeabilized. Membrane permeabilization was associated with a 20 % decrease in bacterial biovolume and to a strong (>50 %) reduction in phosphatidylglycerol (PG) membrane lipids, without altering the fatty acid composition and the degree of unsaturation of acyl chains. PGs are thought to play an important role in membrane stability, by reducing motion of phosphatidylethanolamine (PE) along the membrane bilayer, therefore promoting the formation of inter-lipid hydrogen bonds. In addition, the decrease in intracellular pH induced by SC-CO2 likely alters the chemical properties of phospholipids and the PE/PG ratio. Biophysical effects of SC-CO2 thus cause a strong perturbation of membrane architecture in E. coli, and such alterations are likely associated with its strong inactivation effect. 相似文献
994.
Francesco Ferretti Andrea Sforzi Julia Coats Giovanna Massei 《European Journal of Wildlife Research》2014,60(3):555-558
The impact of wild boar Sus scrofa and feral pigs on ecosystems and human activities is of interest worldwide. Bait-delivered pharmaceuticals such as contraceptives or disease vaccines are increasingly advocated to assist the management of such impacts. We evaluated the Boar-Operated-System (BOS?) to deliver baits to wild boar in a Mediterranean area with a large community of potential nontarget species. In a pre-trial phase (BOS? open), both wild boar and 12 nontarget species (wildlife and livestock) visited the BOS? and eight species consumed the baits. In the trial phase, when the BOS? were closed, only wild boar consumed baits. From pre-trial to trial, the rate of visits by nontarget species to the BOS? decreased significantly, but that of wild boar did not change. We observed that crested porcupines Hystrix cristata prevented the wild boar from using BOS?. We confirmed the effectiveness of BOS? to deliver baits selectively to wild boar in a Mediterranean area. 相似文献
995.
996.
Alessandro Vergara Marisa Franzese Giovanna Bonomi Daniela Giordano H. Caroline Lee Lelio Mazzarella 《Biophysical journal》2009,97(3):866-874
Oxidation of Hbs leads to the formation of different forms of Fe(III) that are relevant to a range of biochemical and physiological functions. Here we report a combined EPR/x-ray crystallography study performed at acidic pH on six ferric tetrameric Hbs. Five of the Hbs were isolated from the high-Antarctic notothenioid fishes Trematomus bernacchii, Trematomus newnesi, and Gymnodraco acuticeps, and one was isolated from the sub-Antarctic notothenioid Cottoperca gobio. Our EPR analysis reveals that 1), in all of these Hbs, at acidic pH the aquomet form and two hemichromes coexist; and 2), only in the three Hbs that exhibit the Root effect is a significant amount of the pentacoordinate (5C) high-spin Fe(III) form found. The crystal structure at acidic pH of the ferric form of the Root-effect Hb from T. bernacchii is also reported at 1.7 Å resolution. This structure reveals a 5C state of the heme iron for both the α- and β-chains within a T quaternary structure. Altogether, the spectroscopic and crystallographic results indicate that the Root effect and hemichrome stability at acidic pH are correlated in tetrameric Hbs. Furthermore, Antarctic fish Hbs exhibit higher peroxidase activity than mammalian and temperate fish Hbs, suggesting that a partial hemichrome state in tetrameric Hbs, unlike in monomeric Hbs, does not remove the need for protection from peroxide attack, in contrast to previous results from monomeric Hbs. 相似文献
997.
Talita Romanatto Erika A. Roman Ana P. Arruda Raphael G. Denis Carina Solon Marciane Milanski Juliana C. Moraes Maria L. Bonfleur Giovanna R. Degasperi Paty K. Picardi Sandro Hirabara Antonio C. Boschero Rui Curi Licio A. Velloso 《The Journal of biological chemistry》2009,284(52):36213-36222
In diet-induced obesity, hypothalamic and systemic inflammatory factors trigger intracellular mechanisms that lead to resistance to the main adipostatic hormones, leptin and insulin. Tumor necrosis factor-α (TNF-α) is one of the main inflammatory factors produced during this process and its mechanistic role as an inducer of leptin and insulin resistance has been widely investigated. Most of TNF-α inflammatory signals are delivered by TNF receptor 1 (R1); however, the role played by this receptor in the context of obesity-associated inflammation is not completely known. Here, we show that TNFR1 knock-out (TNFR1 KO) mice are protected from diet-induced obesity due to increased thermogenesis. Under standard rodent chow or a high-fat diet, TNFR1 KO gain significantly less body mass despite increased caloric intake. Visceral adiposity and mean adipocyte diameter are reduced and blood concentrations of insulin and leptin are lower. Protection from hypothalamic leptin resistance is evidenced by increased leptin-induced suppression of food intake and preserved activation of leptin signal transduction through JAK2, STAT3, and FOXO1. Under the high-fat diet, TNFR1 KO mice present a significantly increased expression of the thermogenesis-related neurotransmitter, TRH. Further evidence of increased thermogenesis includes increased O2 consumption in respirometry measurements, increased expressions of UCP1 and UCP3 in brown adipose tissue and skeletal muscle, respectively, and increased O2 consumption by isolated skeletal muscle fiber mitochondria. This demonstrates that TNF-α signaling through TNFR1 is an important mechanism involved in obesity-associated defective thermogenesis. 相似文献
998.
Giovanna Albertin Diego Guidolin Elisa Sorato Raffaella Spinazzi Alessandra Mascarin Barbara Oselladore Monica Montopoli Michele Antonello Domenico Ribatti 《Regulatory peptides》2009,157(1-3):64-71
Urotensin-II (U-II), along its receptor UT, is widely expressed in the cardiovascular system, where it exerts regulatory actions under both physiological and pathological conditions. In the present study, human vascular endothelial cells (EC) from one arterious and three venous vascular beds were used to investigate in vitro their heterogeneity in terms of expression of U-II and UT and of angiogenic response to the peptide. Real-time PCR and immunocytochemistry demonstrated the expression of UT, as mRNA and protein, in all the EC populations investigated. U-II, on the contrary, was detectable only in EC from aorta and umbilical vein. U-II did not affect the proliferation rate of adult human EC, but induced a moderate proliferative effect on EC from human umbilical vein. When tested in the Matrigel assay, however, all EC exhibited a strong angiogenic response to the peptide, comparable to that of fibroblast growth factor-2 (FGF-2) and it was not associated to an increased expression of vascular endothelial growth factor (VEGF) and/or its receptors. The angiogenic effect of U-II was abolished by the UT antagonist palosuran. Overall, these data suggest that U-II, in addition to the well known role in the regulation of cardiovascular function, also exert a specific angiogenic activity. 相似文献
999.
We have characterised genetically and phenotypically a T-DNA insertion mutant line of A. thaliana (L.) Heynh. selected for Cs resistance when germinating and growing on Cs concentrations up to 600microM, lethal for the wild type. Measures of concentration and localisation of Cs, K, and Ca have been conducted on plants grown in vivo also utilising synchrotron light-based techniques as micro-SRXF (synchrotron radiation induced X-ray micro-fluorescence) and micro-XANES (micro X-ray absorption near edge structure) spectroscopy. We report here an attempt to apply micro-XANES to investigate Cs speciation and to measure the Cs content of living plants. The results obtained with micro-SRXF and micro-XANES spectroscopy complemented the genetic and physiological analyses: a comparison between wild type and mutant plants led to the conclusion that in our case a single gene mutation impairs Cs uptake and translocation, K and Ca homeostasis and plant biomass production. 相似文献
1000.