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991.
992.
Samantha Corrà Riccardo Salvadori Leonardo Bee Vito Barbieri Maddalena Mognato 《Cell biology and toxicology》2017,33(4):373-388
Many aspects of cellular physiology, including cellular response to genotoxic stress, are related to the circadian rhythmicity induced by the molecular clock. The current study investigated if the cellular response to DNA damage is in relation to endogenous expression levels of the PER2 protein, a key component of the molecular regulatory system that confers rhythmicity in mammalian cells. Human normal fibroblasts (CCD-34Lu) were subjected to serum shock to induce circadian oscillations of the PER2 protein and then irradiated with γ- rays at times corresponding to the trough and peak expression of the PER2 protein. To better examine cellular response to DNA damage, the experiments performed in this study were carried out in non-proliferating CCD-34Lu fibroblasts in order to maintain the cell and circadian cycles separated while they were being exposed to genotoxic stress. Study results demonstrated that clonogenic cell survival, double-strand break repair kinetics, and TP53 protein levels were affected in the cells irradiated at the trough than in those irradiated at peak expression of the PER2 protein. 相似文献
993.
Giorgio Maccari Davide Deodato Diego Fiorucci Francesco Orofino Giuseppina I. Truglio Carolina Pasero Riccardo Martini Filomena De Luca Jean-Denis Docquier Maurizio Botta 《Bioorganic & medicinal chemistry letters》2017,27(15):3332-3336
In the last ten years, we identified and developed a new therapeutic class of antifungal agents, the macrocyclic amidinoureas. These compounds are active against several Candida species, including clinical isolates resistant to currently available antifungal drugs. The mode of action of these molecules is still unknown. In this work, we developed an in-silico target fishing procedure to identify a possible target for this class of compounds based on shape similarity, inverse docking procedure and consensus score rank-by-rank. Chitinase enzyme emerged as possible target. To confirm this hypothesis a novel macrocyclic derivative has been produced, specifically designed to increase the inhibition of the chitinase. Biological evaluation highlights a stronger enzymatic inhibition for the new derivative, while its antifungal activity drops probably because of pharmacokinetic issues. Collectively, our data suggest that chitinase represent at least one of the main target of macrocyclic amidinoureas. 相似文献
994.
Landscape simplification weakens the association between terrestrial producer and consumer diversity in Europe 下载免费PDF全文
Matteo Dainese Nick J. B. Isaac Gary D. Powney Riccardo Bommarco Erik Öckinger Mikko Kuussaari Juha Pöyry Tim G. Benton Doreen Gabriel Jenny A. Hodgson William E. Kunin Regina Lindborg Steven M. Sait Lorenzo Marini 《Global Change Biology》2017,23(8):3040-3051
Land‐use change is one of the primary drivers of species loss, yet little is known about its effect on other components of biodiversity that may be at risk. Here, we ask whether, and to what extent, landscape simplification, measured as the percentage of arable land in the landscape, disrupts the functional and phylogenetic association between primary producers and consumers. Across seven European regions, we inferred the potential associations (functional and phylogenetic) between host plants and butterflies in 561 seminatural grasslands. Local plant diversity showed a strong bottom‐up effect on butterfly diversity in the most complex landscapes, but this effect disappeared in simple landscapes. The functional associations between plant and butterflies are, therefore, the results of processes that act not only locally but are also dependent on the surrounding landscape context. Similarly, landscape simplification reduced the phylogenetic congruence among host plants and butterflies indicating that closely related butterflies become more generalist in the resources used. These processes occurred without any detectable change in species richness of plants or butterflies along the gradient of arable land. The structural properties of ecosystems are experiencing substantial erosion, with potentially pervasive effects on ecosystem functions and future evolutionary trajectories. Loss of interacting species might trigger cascading extinction events and reduce the stability of trophic interactions, as well as influence the longer term resilience of ecosystem functions. This underscores a growing realization that species richness is a crude and insensitive metric and that both functional and phylogenetic associations, measured across multiple trophic levels, are likely to provide additional and deeper insights into the resilience of ecosystems and the functions they provide. 相似文献
995.
996.
Guerranti R Ogueli IG Bertocci E Muzzi C Aguiyi JC Cianti R Armini A Bini L Leoncini R Marinello E Pagani R 《Proteomics》2008,8(2):402-412
Previously, we reported the antisnake venom properties of a Mucuna pruriens seed extract (MPE) and tested its in vivo efficacy against Echis carinatus venom (EV) in short- (1 injection) and long-term (three weekly injections) treatments. The aim of the present study was to investigate plasma proteome changes associated with MPE treatments and identify proteins responsible for survival of envenomated mice (CHALLENGED mice). Six treatment groups were studied. Three control groups: one saline, one short-term and one long-term MPE treatment. One group received EV alone. Two test groups received EV with either a short-term or long-term MPE treatment (CHALLENGED mice). The plasma from each group was analysed by 2-DE/MALDI-TOF MS. The most significant changes with treatment were: albumin, haptoglobin, fibrinogen, serum amyloid A and serum amyloid P. Most of these changes were explained by EV effects on coagulation, inflammation and haemolysis. However, MPE treatments prevented the EV-induced elevation in HPT. Consequently, HPT levels were similar to controls in the plasma of CHALLENGED mice. The plasma of CHALLENGED mice showed substantial proteomic modifications. This suggests the mechanism of MPE protection involves the activation of counterbalancing processes to compensate for the imbalances caused by EV. 相似文献
997.
998.
Bandino A Compagnone A Bravoco V Cravanzola C Lomartire A Rossetto C Novo E Cannito S Valfrè di Bonzo L Zamara E Autelli R Parola M Colombatto S 《The international journal of biochemistry & cell biology》2008,40(9):1861-1871
Disruption of cell-to-cell contacts, as observed in many pathophysiological conditions, prime hepatocytes for compensatory hyperplastic response that involves induction of several genes, including proto-oncogenes and other gene targets of beta-catenin signaling pathway. By using cultured hepatocytes and experimental models of adherens junction disruption we have investigated changes in beta-catenin subcellular localization and their relationships with inducible nitric oxide synthase (iNOS) expression. Two experimental models were employed: (a) rat hepatocytes obtained by collagenase liver perfusion within the first 48 h of culture; (b) 48-h old cultured hepatocytes, transiently transfected or not with a plasmid encoding for dominant/negative inhibitory kappa B-alpha, exposed to ethylene glycol-bis-(2-aminoethylether)-N,N,N',N'-tetraacetic acid/LiCl treatment. beta-Catenin signaling and cellular localization, iNOS expression and nuclear factor kappaB involvement, were investigated using morphological, cell and molecular biology techniques. E-cadherin-mediated disruption of cell-to-cell contacts induces early beta-catenin translocation from membrane to cytoplasm and nuclear compartments, events that are followed by up-regulation of c-myc, cyclin D1 and beta-transducin repeat-containing protein expression. This, in turn, resulted eventually in iNOS induction that was mechanistically related to nuclear factor kappaB activation, as unequivocally shown in cells expressing dominant negative inhibitory kappa B-alpha. Our data indicate that E-cadherin disassembly and concomitant inactivation of glycogen synthase kinase-3beta result in nuclear factor kappaB-dependent induction of iNOS in hepatocytes. 相似文献
999.
Georg Wohlfahrt Margaret Anderson-Dunn Michael Bahn Manuela Balzarolo Frank Berninger Claire Campbell Arnaud Carrara Alessandro Cescatti Torben Christensen Sabina Dore Werner Eugster Thomas Friborg Markus Furger Damiano Gianelle Cristina Gimeno Ken Hargreaves Pertti Hari Alois Haslwanter Torbjörn Johansson Barbara Marcolla Celia Milford Zoltan Nagy Eiko Nemitz Nele Rogiers Maria J. Sanz Rolf T.W. Siegwolf Sanna Susiluoto Mark Sutton Zoltan Tuba Francesca Ugolini Riccardo Valentini Roberto Zorer Alexander Cernusca 《Ecosystems》2008,11(8):1338-1351
The net ecosystem carbon dioxide (CO2) exchange (NEE) of nine European mountain grassland ecosystems was measured during 2002–2004 using the eddy covariance method.
Overall, the availability of photosynthetically active radiation (PPFD) was the single most important abiotic influence factor
for NEE. Its role changed markedly during the course of the season, PPFD being a better predictor for NEE during periods favorable
for CO2 uptake, which was spring and autumn for the sites characterized by summer droughts (southern sites) and (peak) summer for
the Alpine and northern study sites. This general pattern was interrupted by grassland management practices, that is, mowing
and grazing, when the variability in NEE explained by PPFD decreased in concert with the amount of aboveground biomass (BMag). Temperature was the abiotic influence factor that explained most of the variability in ecosystem respiration at the Alpine
and northern study sites, but not at the southern sites characterized by a pronounced summer drought, where soil water availability
and the amount of aboveground biomass were more or equally important. The amount of assimilating plant area was the single
most important biotic variable determining the maximum ecosystem carbon uptake potential, that is, the NEE at saturating PPFD.
Good correspondence, in terms of the magnitude of NEE, was observed with many (semi-) natural grasslands around the world,
but not with grasslands sown on fertile soils in lowland locations, which exhibited higher maximum carbon gains at lower respiratory
costs. It is concluded that, through triggering rapid changes in the amount and area of the aboveground plant matter, the
timing and frequency of land management practices is crucial for the short-term sensitivity of the NEE of the investigated
mountain grassland ecosystems to climatic drivers. 相似文献
1000.
Eva Terzibasi Dario Riccardo Valenzano Mauro Benedetti Paola Roncaglia Antonino Cattaneo Luciano Domenici Alessandro Cellerino 《PloS one》2008,3(12)