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951.
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Alessandro Ghezzo Paola Visconti Provvidenza M. Abruzzo Alessandra Bolotta Carla Ferreri Giuseppe Gobbi Gemma Malisardi Stefano Manfredini Marina Marini Laura Nanetti Emanuela Pipitone Francesca Raffaelli Federica Resca Arianna Vignini Laura Mazzanti 《PloS one》2013,8(6)
It has been suggested that oxidative stress may play a role in the pathogenesis of Autism Spectrum Disorders (ASD), but the literature reports somewhat contradictory results. To further investigate the issue, we evaluated a high number of peripheral oxidative stress parameters, and some related issues such as erythrocyte membrane functional features and lipid composition. Twenty-one autistic children (Au) aged 5 to 12 years, were gender and age-matched with 20 typically developing children (TD). Erythrocyte thiobarbituric acid reactive substances, urinary isoprostane and hexanoyl-lysine adduct levels were elevated in Au, thus confirming the occurrence of an imbalance of the redox status of Au, whilst other oxidative stress markers or associated parameters (urinary 8-oxo-dG, plasma radical absorbance capacity and carbonyl groups, erythrocyte superoxide dismutase and catalase activities) were unchanged. A very significant reduction of Na+/K+-ATPase activity (−66%, p<0.0001), a reduction of erythrocyte membrane fluidity and alteration in erythrocyte fatty acid membrane profile (increase in monounsaturated fatty acids, decrease in EPA and DHA-ω3 with a consequent increase in ω6/ω3 ratio) were found in Au compared to TD, without change in membrane sialic acid content. Some Au clinical features appear to be correlated with these findings; in particular, hyperactivity score appears to be related with some parameters of the lipidomic profile and membrane fluidity. Oxidative stress and erythrocyte membrane alterations may play a role in the pathogenesis of ASD and prompt the development of palliative therapeutic protocols. Moreover, the marked decrease in NKA could be potentially utilized as a peripheral biomarker of ASD. 相似文献
953.
Valentina Marziano Piero Poletti Giorgio Guzzetta Marco Ajelli Piero Manfredi Stefano Merler 《Proceedings. Biological sciences / The Royal Society》2015,282(1804)
Varicella zoster virus (VZV) causes varicella upon first exposure and may reactivate later in life into herpes zoster (HZ), with a risk that is thought to be reduced by re-exposures to VZV. Given the decades-long time scales of reactivation and its dependence on the accumulation of re-exposure episodes, adopting a long-term perspective may be useful to correctly interpret current epidemiological trends of VZV. In this study, we investigate the possible impact of demographic changes on varicella and HZ in Spain, using an age-structured mathematical model informed with historical demographic data and calibrated against age-specific profiles of varicella seroprevalence and HZ incidence data. The model qualitatively reproduces the remarkable growth of HZ incidence observed in Spain between 1997 and 2004, before the introduction of varicella vaccination programmes. We demonstrate that this growth may be partially ascribed to the reduction of varicella circulation that followed the overall decline of the birth rate in the twentieth century. Model predictions further suggest that, even under the most optimistic projections, HZ incidence will continue its rise until at least 2040. Considering the effect of demographic changes can help interpreting variations in epidemiological trends of HZ, contributing to a more accurate evaluation of vaccination programmes against VZV. 相似文献
954.
Daniela Giordano Roberta Russo Daniela Coppola Giovanna Altomonte Guido di Prisco Stefano Bruno Cinzia Verde 《Hydrobiologia》2015,761(1):293-312
Notothenioidei, the taxonomic group of teleosts that dominates the Southern Ocean and dwell in the Ross Sea at large, provide an example of marine species that underwent unique adaptations to life at low temperatures and high oxygen concentrations, resulting in morphological, physiological, genomic, and biochemical peculiarities in comparison with warm-water fish. Global Warming raises concerns over the fate of these stenothermal fish, as their adaptation has been accompanied by irreversible genomic losses, which suggest a poor genetic potential to adapt to warmer climates. Specifically, this review focuses on adaptation of proteins belonging to the globin superfamily, which include the respiratory proteins hemoglobin and myoglobin and the non-respiratory proteins neuroglobin and cytoglobin. Here, we describe their molecular adaptations to cold temperatures in the framework of the physiology of oxygen transport and management of oxidative stress in fish species largely populating the Ross Sea. 相似文献
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956.
M. Antonio Todaro D. Timothy J. Littlewood Maria Balsamo Elisabeth A. Herniou Stefano Cassanelli Giancarlo Manicardi Annarita Wirz Paolo Tongiorgi 《Zoologischer Anzeiger》2003,242(2):145-156
Gastrotrichs are meiobenthic invertebrates of obscure origin and unclear phylogenetic alliances. Uncertainties also plague the intra-group relationship with major contrasts between the evolutionary scenarios inferred from morphology or molecules. In this study we analysed partial sequences of the 18S rDNA gene of 18 taxa (14 new and 4 published) to test morphological estimates of gastrotrich phylogeny and to verify whether controversial interrelationships from previous molecular data are due to poor sampling. Data were analysed using both maximum parsimony and maximum likelihood. MP topology was then forced to reflect published morphological estimates and the most parsimonious solutions from each constraint analysis was statistically compared against the unconstrained solution. MP analysis yielded a single tree with few nodes well supported by bootstrap resampling. These included the monophyly of the Chaetonotidae and the internal relationships of the members of this family, with Aspidiophorus appearing as the most basal member. The monophyly of the Turbanellidae was also well supported with some suggestion that its sister group might be Mesodasys. Lepidodasyidae was found to be an unnatural taxon with Lepidodasys forming a separated clade but unrelated also to the Thaumastodermatidae. With the exception of genera Lepidodasys and Neodasys, the Macrodasyida appeared to be resolved separately from the Chaetonotida, and Dactylopodola was resolved as the most basal macrodasyid. ML analysis yielded a tree not too dissimilar from MP, although Dactylopodola and Xenodasys were resolved as a clade. Statistics indicate that the output from our MP analysis is compatible with the classical view placing representatives of the two orders within two distinct evolutionary lines. Most of the constrained solutions, except the shortest, corroborate the monophyly of the two orders, whereas all five constrained solutions support also the notion that sees Neodasys as an early divergent clade along the Chaetonotida branch. Thus, results are generally compatible with the hypothesised evolutionary scenario based on morphological data, but are in contrast with previous findings from molecules. Future research should consider using the complete SSU rDNA gene sequence in their analysis and additional genes for deeper resolution. 相似文献
957.
Pini A Lozzi L Bernini A Brunetti J Falciani C Scali S Bindi S Di Maggio T Rossolini GM Niccolai N Bracci L 《Amino acids》2012,43(1):467-473
The tetra-branched peptide M33 (Pini et al. in FASEB J 24:1015-1022, 2010) is under evaluation in animal models for its activity as antimicrobial agent in lung infections and sepsis. The preclinical development of a new drug requires medium-scale manufacture for tests of efficacy, biodistribution, pharmacokinetics and toxicity. In order to produce the most suitable peptide form for these purposes, we evaluated the behaviour of the peptide M33 obtained with different counter-ions. We compared activity and toxicity in vitro and in vivo of the peptide M33 produced as trifluoroacetate salt (TFacetate) and as acetate salt. The two forms did not differ substantially in terms of efficacy in vitro or in vivo but showed different toxicities for human cells and in animals. M33-TFacetate proved to be 5-30% more toxic than M33-acetate for cells derived from normal bronchi and cells carrying ΔF508 mutation in the CFTR gene, the most frequent variant in cystic fibrosis. M33-TFacetate produced manifest signs of in vivo toxicity immediately after administration, whereas M33-acetate only generated mild signs, which disappeared within a few hours. The peptide M33-acetate proved more suitable for the development of a new drug, and was therefore chosen for further characterization. 相似文献
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