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991.
Emiliano Manzo Paola Bartolommei Alessandro Giuliani Gabriele Gentile Francesco Dessì-Fulgheri Roberto Cozzolino 《Acta theriologica》2018,63(3):357-367
Studies at small spatial scale are often fundamental to highlight the behavioural plasticity of a species and thus have important implications for conservation planning, in particular for species usually considered as habitat specialists. We investigated second-order habitat selection of the European pine marten in an area dominated by deciduous oak forest and open fields in central Italy, by radio-tracking 16 pine martens (eight males, eight females). Pine martens placed home ranges in areas with more open field than in the study area, whereas woodland (oak and conifer forests) comprised a smaller portion of the home range than predominant forest character of the studied area. Although the presence of the species in the open habitats has been documented, to our knowledge, our results provide the first evidence of home range establishment in this cover type by pine marten at population level. The combination of low predation risk and high availability of resources could allow pine martens to occupy open fields in our study area. We highlighted different individual strategies of habitat selection, with some individuals placing home ranges in areas with high forest coverage while others occupying open areas. We found no effects of sex and body condition on habitat selection, and this could indicate that in the study area, both forested and non-forested cover types, such as open fields, shrub and anthropic areas, can provide adequate food, overhead cover and resting sites for all individuals. Pine marten ability to occupy open fields seems thus more related to the behavioural flexibility of the species, rather than to the need to supplement dens and forage from complementary lower quality habitat. The high quality of the Mediterranean continental area studied could also explain the selection of open areas by the pine marten. Our results offer useful information on pine marten ecology and may be helpful for conservation management of this species in southern Europe. 相似文献
992.
Single-sample preparation for simultaneous cellular redox and energy state determination 总被引:1,自引:0,他引:1
Lazzarino G Amorini AM Fazzina G Vagnozzi R Signoretti S Donzelli S Di Stasio E Giardina B Tavazzi B 《Analytical biochemistry》2003,322(1):51-59
A simple and reliable method for the preparation of biological samples for the evaluation of biochemical parameters representative of the redox and energy states, such as glutathione (GSH), oxidized glutathione (GSSG), oxidized nicotinamide adenine dinucleotide (NAD+), reduced nicotinamide adenine dinucleotide (NADH), oxidized nicotinamide adenine dinucleotide phosphate (NADP+), reduced nicotinamide adenine dinucleotide phosphate (NADPH), coenzyme A (CoASH), oxidized CoASH, ascorbate, malondialdehyde, oxypurines, nucleosides, and energy metabolites, is presented. Fast deproteinization under nonoxidizing conditions is obtained by tissue homogenization in ice-cold, nitrogen-saturated CH3CN + 10 mM KH2PO4 (3:1; v:v), pH 7.40. After sample centrifugation to pellet precipitated proteins, organic solvent removal is performed on clear supernatants by three washings with large volumes of high-performance liquid chromatography (HPLC)-grade chloroform. The remaining aqueous phase, free of solvent and any lipid-soluble substances that may interfere with the further metabolite analysis, is used for the simultaneous ion-pairing HPLC determination of 39 compounds by means of a Kromasil C-18, 250 x 4.6-mm, 5-microm-particle-size column with tetrabutylammonium hydroxide as the pairing reagent. Results obtained by using the present method to prepare different rat tissue extracts demonstrate that it is possible to perform a single tissue preparation only for monitoring, in the same sample, compounds representative of the redox state (through the direct determination of GSH, GSSG, NAD+, NADH, NADP+, NADPH, CoASH, and oxidized CoASH) and of the cell energy state (by the analysis of oxypurines, nucleosides, and energy metabolites). Applicability of this sample processing procedure to quantify variations of the aforementioned compounds under pathological conditions was effected in rats subjected to moderate closed-head trauma. 相似文献
993.
Scotti C Iamele L Alessandrini A Vannini V Cazzalini O Lazzè MC Melli R Savio M Pizzala R Stivala LA Biglieri S Tomasi A Bianchi L 《Mitochondrion》2003,2(5):361-373
We investigated the molecular relationships between lipid peroxidation and mitochondrial DNA (mtDNA) single strand breaks (ssb) in isolated rat hepatocytes and mitochondria exposed to tert-butylhydroperoxide (TBH). Our results show that mtDNA ssb induced by TBH are independent of lipid peroxidation and dependent on the presence of iron and of hydroxyl free radicals. These data contribute to the definition of the mechanisms whereby mtDNA ssb are induced and provide possible molecular targets for the prevention of this kind of damage in vivo. 相似文献
994.
Bradbury A Velappan N Verzillo V Ovecka M Chasteen L Sblattero D Marzari R Lou J Siegel R Pavlik P 《Trends in biotechnology》2003,21(7):312-317
There are many ways in which the use of antibodies and antibody selection can be improved and developed for high-throughput characterization. Standard protocols, such as immunoprecipitation, western blotting and immunofluorescence, can be used with antibody fragments generated by display technologies. Together with novel approaches, such as antibody chips and intracellular immunization, these methods will yield useful proteomic data following adaptation of the protocols for increased reliability and robustness. To date, most work has focused on the use of standard, well-characterized commercial antibodies. Such protocols need to be adapted for broader use, for example, with antibody fragments or other binders generated by display technologies, because it is unlikely that traditional approaches will provide the required throughput. 相似文献
995.
996.
Laura Brunelli Giuseppe Ristagno Renzo Bagnati Francesca Fumagalli Roberto Latini Roberto Fanelli Roberta Pastorelli 《Metabolomics : Official journal of the Metabolomic Society》2013,9(4):839-852
The mechanisms responsible for post-resuscitation myocardial and cerebral dysfunction are not well understood, especially in the early post-resuscitation phases. In this investigation, we first adopted unbiased mass spectrometry-based metabolomic profiling to identify perturbations in circulating metabolites in a rat model of cardiac arrest and cardiopulmonary resuscitation. Our findings strongly indicated early alterations in a major route of the tryptophan catabolism, namely the kynurenines pathway, after resuscitation. Specific metabolites involved in the tryptophan catabolism were quantified absolutely using liquid chromatography-multiple reaction monitoring-mass spectrometry. Tryptophan plasma concentration fell significantly very early in the post-resuscitation phase, while its metabolites, l-kynurenine, kynurenic acid, 3-hydroxyanthranilic acid and 5-hydroxyindoleacetic acid, rose significantly. Changes in their concentration reflected changes in rat post-resuscitation myocardial dysfunction. Elevated plasma level of kynurenic acid, 3-hydroxyanthranilic acid were associated with significant decrease in ejection fraction and stroke volume. It is well known that kynurenines pathway is involved in the pathogenesis of numerous central nervous system disorders. By implication, altered levels of tryptophan metabolites in the early post resuscitation phase might contribute to the degree of cognitive recovery. Our results suggest that kynurenine pathway is activated early following resuscitation from cardiac arrest and might account for the severity of post-resuscitation syndrome. Our explorative investigation indicate that metabolomics can help to clarify unexplored biochemical pathways in cardiopulmonary resuscitation. 相似文献
997.
Roberto Consonni Rita Limiroli Renato Longhi Ernesto Manera Giuseppe Vecchio Laura Ragona Antonio G. Siccardi Lucia Zetta 《Biopolymers》1996,38(3):423-435
CD and nmr characterizations are reported for the 23-mer peptide CMC3, corresponding to residues 577–599 of gp41, the transmembrane glycoprotein of the human immunodeficiency virus 1. Concentration, temperature, and pH dependencies of CD and nmr spectra are indicative of self-association with a consequent stabilization of secondary structural elements in water. The addition to the water solution of small amounts of trifluoroethanol induces a secondary structure, mostly due to the presence of helical elements. The amphipathic character of the helix and the presence of three hydrophobic 4/3 heptad repeats suggest that the peptide could be structured in a symmetric association of helices, such as in a coiled-coil structure. This behavior is discussed in terms of a possible role of this segment in the gp41 envelope oligomerization. © 1996 John Wiley & Sons, Inc. 相似文献
998.
Laura Pasin Giovanni Landoni Maria Lourdes Castro Luca Cabrini Alessandro Belletti Paolo Feltracco Gabriele Finco Andrea Carozzo Roberto Chiesa Alberto Zangrillo 《PloS one》2013,8(12)
Objective
Statins are among the most prescribed drugs worldwide and their recently discovered anti-inflammatory effect seems to have an important role in inhibiting proinflammatory cytokine production, chemokines expression and counteracting the harmful effects of sepsis on the coagulation system. We decided to perform a meta-analysis of all randomized controlled trials ever published on statin therapy in septic patients to evaluate their effect on survival and length of hospital stay.Data sources and study selection
Articles were assessed by four trained investigators, with divergences resolved by consensus. BioMedCentral, PubMed, Embase and the Cochrane Central Register of clinical trials were searched for pertinent studies. Inclusion criteria were random allocation to treatment and comparison of statins versus any comparator in septic patients.Data extraction and synthesis
Data from 650 patients in 5 randomized controlled studies were analyzed. No difference in mortality between patients receiving statins versus control (44/322 [14%] in the statins group vs 50/328 [15%] in the control arm, RR = 0.90 [95% CI 0.65 to 1.26], p = 0.6) was observed. No differences in hospital stay (p = 0.7) were found.Conclusions
Published data show that statin therapy has no effect on mortality in the overall population of adult septic patients. Scientific evidence on statins role in septic patients is still limited and larger randomized trials should be performed on this topic. 相似文献999.
Paulo Roque Obreli-Neto Leonardo Régis Leira Pereira Camilo Molino Guidoni André de Oliveira Baldoni Srecko Marusic Divaldo Pereira de Lyra-Júnior Kelsen Luis de Almeida Ana Claudia Montolezi Pazete Janaina Dutra do Nascimento Mitja Kos Edmarlon Girotto Roberto Kenji Nakamura Cuman 《PloS one》2013,8(12)
1000.
Maria Pia Rigobello Roberto Stevanato Federico Momo Sabrina Fabris Guido Scutari Rita Boscolo 《Free radical research》2013,47(3):315-321
Propofol (2,6-diisopropylphenol), some substituted phenols (2,6-dimethylphenol and 2,6-ditertbutylphenol) and their 4-nitrosoderivatives have been compared for their scavenging ability towards 1,1-diphenyl-2-picrylhydrazyl and for their inhibitory action on lipid peroxidation. These products were also compared to the classical antioxidants butylated hydroxytoluene and butylated hydroxyanisole. When measuring the reactivity of the various phenolic derivatives with 1,1-diphenyl-2-picrylhydrazyl the following order of effectiveness was observed: butylated hydroxyanisole>propofol>2,6-dimethylphenol>2,6-di-tertbutylphenol?>?butylated hydroxytoluene. In cumene hydroperoxide-dependent microsomal lipid peroxidation, propofol acts as the most effective antioxidant, while butylated hydroxyanisole, 2,6-di-tertbutylphenol and butylated hydroxytoluene exhibit a rather similar effect, although lower than propofol. In the iron/ascorbate-dependent lipid peroxidation propofol, at concentrations higher than 10?μM, exhibits antioxidant properties comparable to those of butylated hydroxytoluene and butylated hydroxyanisole. 2,6-Dimethylphenol is scarcely effective in both lipoperoxidative systems. The antioxidant properties of the various molecules depend on their hydrophobic characteristics and on the steric and electronic effects of their substituents. However, the introduction of the nitroso group in the 4-position almost completely removes the antioxidant properties of the examined compounds. The nitrosation of the aromatic ring of antioxidant molecules and the consequent loss of antioxidant capacity can be considered a condition potentially occurring in vivo since nitric oxide and its derivatives are continuously formed in biological systems. 相似文献