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31.
Rossetti Y 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2003,358(1435):1269-1275
Two main types of dissociation can be considered in order to articulate action and abstraction. Vision for action and vision for perception are often described as dissociated systems at both anatomical and functional levels. Within this framework, abstraction should be specific to perceptual representation, whereas the action system would simply analyse the objective metric of space. By contrast, one may focus on dissociations within the action system. In this case, one will accept that action may involve abstract representations, at least during movement preparation. But a specific visuomotor level of processing can be described that appears to comply with the spatial properties of the relationship between the actor and the environment. This system would be specialized for fast movement guidance towards pre-defined goals. Such an automatic piloting system would thus be free of abstraction. 相似文献
32.
Falvo A Levantesi C Rossetti S Seviour RJ Tandoi V 《Journal of applied microbiology》2001,91(2):299-305
AIMS: The study investigated the physiology of Amaricoccus kaplicensis to determine whether it could outcompete polyphosphate accumulating bacteria in activated sludge systems removing phosphorus, by preferentially assimilating substrates in the anaerobic stages of these processes. METHODS AND RESULTS: The storage processes were investigated under anaerobic, anoxic and aerobic conditions in both batch and periodically fed cultures in an aerobic sequencing batch reactor (SBR). Amaricoccus kaplicensis showed a high capacity for storing aerobically large amounts of acetate as poly beta-hydroxybutyrate (PHB) at high rates. However, no acetate assimilation under anaerobic conditions and very slow assimilation under anoxic conditions could be detected. CONCLUSION: Amaricoccus kaplicensis in pure culture does not behave as polyphosphate accumulating bacteria competitor; therefore it is difficult to understand why anaerobic/aerobic systems often contain such large numbers of Amaricoccus cells. SIGNIFICANCE AND IMPACT OF THE STUDY: Amaricoccus kaplicensis is probably not responsible for the failure of activated sludge systems removing phosphorus, and other organisms capable of anaerobic substrate assimilation should be sought. 相似文献
33.
Circulating insulin inhibits endogenous glucose production. Here we report that bidirectional changes in hypothalamic insulin signaling affect glucose production. The infusion of either insulin or a small-molecule insulin mimetic in the third cerebral ventricle suppressed glucose production independent of circulating levels of insulin and of other glucoregulatory hormones. Conversely, central antagonism of insulin signaling impaired the ability of circulating insulin to inhibit glucose production. Finally, third-cerebral-ventricle administration of inhibitors of ATP-sensitive potassium channels, but not of antagonists of the central melanocortin receptors, also blunted the effect of hyperinsulinemia on glucose production. These results reveal a new site of action of insulin on glucose production and suggest that hypothalamic insulin resistance can contribute to hyperglycemia in type 2 diabetes mellitus. 相似文献
34.
Intersection of mitochondrial fission and fusion machinery with apoptotic pathways: Role of Mcl‐1 下载免费PDF全文
Giampaolo Morciano Gaia Pedriali Luigi Sbano Tommaso Iannitti Carlotta Giorgi Paolo Pinton 《Biology of the cell / under the auspices of the European Cell Biology Organization》2016,108(10):279-293
Mitochondria actively contribute to apoptotic cell death through mechanisms including the loss of integrity of the outer mitochondrial membrane, the release of intermembrane space proteins, such as cytochrome c, in the cytosol and the caspase cascade activation. This process is the result of careful cooperation not only among members of the Bcl‐2 family but also dynamin‐related proteins. These events are often accompanied by fission of the organelle, thus linking mitochondrial dynamics to apoptosis. Emerging evidences are suggesting a fine regulation of mitochondrial morphology by Bcl‐2 family members and active participation of fission–fusion proteins in apoptosis. The debate whether in mitochondrial morphogenesis the role of Bcl‐2 family members is functionally distinct from their role in apoptosis is still open and, above all, which morphological changes are associated with cell death sensitisation. This review will cover the findings on how the mitochondrial fission and fusion machinery may intersect apoptotic pathways focusing on recent advances on the key role played by Mcl‐1. 相似文献
35.
Filamentous Alphaproteobacteria associated with bulking in industrial wastewater treatment plants 总被引:1,自引:0,他引:1
Levantesi C Beimfohr C Geurkink B Rossetti S Thelen K Krooneman J Snaidr J van der Waarde J Tandoi V 《Systematic and applied microbiology》2004,27(6):716-727
The phylogeny and distribution of filamentous Alphaproteobacteria, morphologically similar to “Nostocoida limicola” and Eikelboom Type 021N that cause the solids separation problem of bulking in industrial activated sludge plants is described here. A combination of culture-dependent and culture-independent molecular methods has characterized 5 novel species. 16S rRNA targeted oligonucleotide probes were designed for their in situ identification by fluorescence in situ hybridisation (FISH) and used to monitor their presence in 86 WWTPs treating different industrial effluents in four European countries. The involvement of these bacteria in bulking in these plants was confirmed. Filaments hybridising with the ALF-968 probe for the Alphaproteobacteria were present in 65% of the WWTPs examined. They were dominant and therefore probably responsible for bulking in 25.5% of them. The heterogeneous filamentous alphaproteobacterial populations in these communities could be completely identified after application of the oligonucleotide probes used in this study in 91% of the plants containing them. The only filamentous Alphaproteobacteria retrieved in pure culture was isolated from three different industrial WWTPs plants. None of these isolates could grow anaerobically on glucose or denitrify, but all grew aerobically and heterotrophically on a range of carbon sources. Although morphologically similar to the Eikelboom Type 021N morphotype, they were not involved in sulphur metabolism. These bacteria accumulated lipidic storage granules that were associated with their presence under the unbalanced growth conditions existing in these plants. 相似文献
36.
Caroline Tanski Bueno Cláudia Maria Dornelles da Silva Regina Bones Barcellos Juliana da Silva Carla Rossana dos Santos Jo?o Evangelista Sampaio Menezes Honório Sampaio Menezes Maria Lucia Rosa Rossetti 《Genetics and molecular biology》2014,37(3):496-499
The aim of this study was to evaluate the association between the frequency of micronuclei (MN) and the cellular changes detected in the conventional Papanicolaou test. One hundred and seventy-four Papanicolaou test smears with cellular changes were examined. MN screening was done in cytopathological smears by counting 1,000 cervical cells in a light microscope. MN frequencies were significantly higher in the group with cellular changes compared to the control group (p < 0.001). The mean MN frequencies were 0.95 ± 1.12 (mean ± SD) in the control group (n = 223), 2.98 ± 1.20 in individuals with atypical squamous cells of undetermined significance (ASC-US) (n = 50), 4.04 ± 1.45 in cervical intraepithelial neoplasia (CIN) I (n = 52), 5.97 ± 1.83 in CIN II (n = 30), 7.29 ± 1.55 in CIN III (n = 17) and 8.64 ± 1.55 in invasive cancer (n = 25). These findings suggest that MN monitoring should be included as an additional criterion for the early detection of cytogenetic damage in routine examinations. This monitoring should be done in the same smear as used for cytopathological examination. More specific and systematic studies are necessary to confirm this proposal. 相似文献
37.
Luciano Elias Da Cruz Perez Ana Lucia Machado Sebastião Vicente Canevarolo Carlos Eduardo Vergani Eunice Teresinha Giampaolo Ana Cláudia Pavarina 《Gerodontology》2010,27(1):62-69
doi:10.1111/j.1741‐2358.2009.00292.x Effect of reline material and denture base surface treatment on the impact strength of a denture base acrylic resin Objective: In this study, the effect of relining and surface treatment on the impact strength (IS) of a heat‐polymerising denture base acrylic resin (Lucitone 550‐L) was evaluated. Materials and methods: Rectangular bars of L were made (60 × 6 × 2 mm) and relined (2 mm) with the relining resins Ufi Gel Hard (UH) and Tokuso Rebase Fast (TR). Specimens relined with L and intact L, TR and UH specimens were also made (60 × 6 × 4 mm), for comparison. Before relining, the L surface was left untreated or wetted with methyl methacrylate monomer and/or the bonding agents (BA) supplied by manufacturers of the reline resins. V‐notches were machined at the midpoint of the length of all specimens. The notches were made either across the width (Nw) or across the thickness of the specimens (Nth). The Charpy impact test was performed using a 0.5‐J pendulum, which had been specially designed and constructed. Data were analysed separately for each notch position using one‐way analysis of variance and Tukey honestly significant difference post‐hoc test (p = 0.05). Results: The IS of L was similar to that of L/L. For the Nw notch, treating the denture base L with TR BA and relining with TR reline material produced the highest IS. Conclusion: The IS of specimens made from heat polymerising acrylic resin Lucitone 550 was increased after relining using the hard chairside reline resin TR with its proprietary BA. 相似文献
38.
Marco Forghieri Christian Laggner Paolo Paoli Thierry Langer Giampaolo Manao Guido Camici Lucia Bondioli Fabio Prati Luca Costantino 《Bioorganic & medicinal chemistry》2009,17(7):2658-2672
Protein tyrosine phosphatases (PTP) are crucial elements in eukaryotic signal transduction. Several reports suggested that the LMW-PTP family has oncogenic relevance. Moreover, LMW-PTP has been recognized as a negative regulator of insulin-mediated mitotic and metabolic signaling. Thus, inhibition of the LMW-PTP can be considered an attractive approach for the design of new therapeutic agents for the treatment of type II diabetes and for new antitumoral drugs. To date very few (and weak) inhibitors of LMW-PTP have been identified. On the basis of the reported weak activity of some flavonoids on phosphatases, we discovered a lead that originated a new class of highly active LMW-PTP inhibitors; these compounds inhibit also PTP-1B and are active in cellular assays. Docking experiments and SAR highlighted the possible binding mode of these compounds to the enzyme, putting the background for the future optimization of their inhibitory activity and selectivity towards the closely related enzyme PTP-1B. 相似文献
39.
Sabio y García JV Bigi F Rossetti O Campos E 《Microbes and infection / Institut Pasteur》2010,12(14-15):1236-1243
Immunodominant MPB83 antigen from Mycobacterium bovis was expressed as a chimeric protein fused to either β-galactosidase, outer membrane lipoprotein OMP19 or periplasmic protein BP26 in gram-negative Brucella abortus S19, in all cases driven by each gene's own promoter. All fusion proteins were successfully expressed and localized in the expected subcellular fraction. Moreover, OMP19-MPB83 was processed as a lipoprotein when expressed in B. abortus. Splenocytes from BALB/c mice immunized with the recombinant S19 strains carrying the genes coding for the heterologous antigens in replicative plasmids, showed equally specific INF-γ production in response to MPB83 stimulation. Association to the lipid moiety of OMP19 presented no advantage in terms of immunogenicity for MPB83. In contrast, fusion to BP26, which was encoded by an integrative plasmid, resulted in a weaker immune response. None of the constructions affected the survival rate or the infection pattern of Brucella. We concluded that B. abortus S19 is an appropriate candidate for the expression of M. bovis antigens both associated to the membrane or cytosolic fraction and may provide the basis for a future combined vaccine for bovine brucellosis and tuberculosis. 相似文献
40.
Giampaolo Barone Angela Ruggirello Alessio Terenzi 《Journal of inorganic biochemistry》2010,104(7):765-773
The photophysical and photochemical properties of the cationic ZnII complex of 5-triethyl ammonium methyl salicylidene ortho-phenylendiimine (ZnL2+) interacting with native DNA were investigated by steady state and time-resolved fluorescence spectroscopies. Experimental results indicate that, in the presence of DNA, ZnL2+ is efficiently protected from a photochemical process, which occurs when it is in the free state dispersed in aqueous solution. The analysis of the absorption and emission spectra of ZnL2+, both stored in the dark and after exposure to tungsten lamp light for 24 h, corroborated by quantum chemical calculations, allowed us to point out that ZnL2+ undergoes a photoinduced two-electron oxidation process. According to this picture, the protective action of DNA toward the intercalated ZnL2+ was attributed to an effective inhibition of the ZnL2+ photooxidation. In this context, it can be considered that DNA-intercalated ZnL2+ is located in a region more hydrophobic than that sensed in the bulk water solvent. Moreover, by a thorough analysis of steady state and time-resolved fluorescence spectra, the interaction process can be consistently explained in terms of a complete intercalation of the complex molecules and that the polarity of the environment sensed by intercalated ZnL2+ is comprised between that of methanol and ethanol. 相似文献