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Gender differences in cooperative choices and their neural correlates were investigated in a situation where reputation represented a crucial issue. Males and females were involved in an economic exchange (trust game) where economic and reputational payoffs had to be balanced in order to increase personal welfare. At the behavioral level, females showed a stronger reaction to negative reputation judgments that led to higher cooperation than males, measured by back transfers in the game. The neuroanatomical counterpart of this gender difference was found within the reward network (engaged in producing expectations of positive results) and reputation-related brain networks, such as the self-control network (engaged in strategically resisting the temptation to defect) and the mentalizing network (engaged in thinking about how one is viewed by others), in which the dorsolateral prefrontal cortex (DLPFC) and the medial (M)PFC respectively play a crucial role. Furthermore, both DLPFC and MPFC activity correlated with the amount of back transfer, as well as with the personality dimensions assessed with the Big-Five Questionnaire (BFQ-2). Males, according to their greater DLPFC recruitment and their higher level of the BFQ-2 subscale of Dominance, were more focused on implementing a profit-maximizing strategy, pursuing this target irrespectively of others'' judgments. On the contrary, females, according to their greater MPFC activity and their lower level of Dominance, were more focused on the reputation per se and not on the strategic component of reputation building. These findings shed light on the sexual dimorphism related to cooperative behavior and its neural correlates.  相似文献   
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Soybean (Glycine max) is one of the most important cultivated plants worldwide as a source of protein‐rich foods and animal feeds. Anthracnose, caused by different lineages of the hemibiotrophic fungus Colletotrichum, is one of the main limiting factors to soybean production. Losses due to anthracnose have been neglected, but their impact may threaten up to 50% of the grain production.TaxonomyWhile C. truncatum is considered the main species associated with soybean anthracnose, recently other species have been reported as pathogenic on this host. Until now, it has not been clear whether the association of new Colletotrichum species with the disease is related to emerging species or whether it is due to the undergoing changes in the taxonomy of the genus.Disease symptomsTypical anthracnose symptoms are pre‐ and postemergence damping‐off; dark, depressed, and irregular spots on cotyledons, stems, petioles, and pods; and necrotic laminar veins on leaves that can result in premature defoliation. Symptoms may evolve to pod rot, immature opening of pods, and premature germination of grains.ChallengesAs accurate species identification of the causal agent is decisive for disease control and prevention, in this work we review the taxonomic designation of Colletotrichum isolated from soybean to understand which lineages are pathogenic on this host. We also present a comprehensive literature review of soybean anthracnose, focusing on distribution, symptomatology, epidemiology, disease management, identification, and diagnosis. We consider the knowledge emerging from population studies and comparative genomics of Colletotrichum spp. associated with soybean providing future perspectives in the identification of molecular factors involved in the pathogenicity process.Useful websiteUpdates on Colletotrichum can be found at http://www.colletotrichum.org/.All available Colletotrichum genomes on GenBank can be viewed at http://www.colletotrichum.org/genomics/.  相似文献   
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It is now well established that Southern European peninsulas have been major glacial refugia for temperate species during Pleistocene climatic oscillations. However, substantial environmental changes occurred also within these peninsulas throughout the Pleistocene, raising questions about the role and interplay of various microevolutionary processes in shaping patterns of intraspecific diversity within these areas. Here, we investigate the patterns of genetic variation in the bank vole Myodes glareolus within the Italian peninsula. By using a panel of 13 microsatellite loci, we found more intraspecific variation than expected based on previous assessments. Indeed, both Bayesian and ordination‐based clustering analyses of variation recovered five main geographic/genetic clusters along the peninsula, with three clusters geographically restricted to the southern portion of the peninsula. This clustering is supported by previous evidences of some morphological distinctiveness among these populations. This pattern can be explained by a refugia‐within‐refugia scenario, with the occurrence of multiple sub‐refugia for the bank vole within the Italian peninsula, likely promoted by the major palaeo‐environmental changes which affected forested habitats within this area during the Pleistocene. Moreover, our results support a scenario whereby the high levels of intraspecific diversity observed within major Pleistocene refugia are better explained by dynamic microevolutionary processes occurred within these areas, rather than by long‐term demographic stability of refugial population. Finally, the narrow and isolated distribution of some of the identified lineages suggests the need for future assessments of their conservation and taxonomic status.  相似文献   
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Inhibition of the proteasome, the multicatalytic protease complex responsible for the turnover of many cellular proteins, represents an attractive target in the development of new drug therapies, proteasome inhibitors being potentially useful tools for the treatment of pathologies such as cancer, as well as inflammatory, immune and neurodegenerative diseases. Based on our previous development of a new class of inhibitors bearing a C‐terminal VE cluster able to interact with catalytic threonine, we report herein the synthesis and activity of new VE‐based peptide analogs bearing an additional allyl pharmacophore unit at the C‐ or N‐terminal position of the pseudotripeptide sequence. In the new series, the structural modification carried out to the prototype determine a decrease of proteasome inhibition. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
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Background

Sphingolipids take part in immune response and can initiate and/or sustain inflammation. Various inflammatory diseases have been associated with increased ceramide content, and pharmacological reduction of ceramide diminishes inflammation damage in vivo. Inflammation and susceptibility to microbial infection are two elements in a vicious circle. Recently, sphingolipid metabolism inhibitors were used to reduce infection. Cystic fibrosis (CF) is characterized by a hyper-inflammation and an excessive innate immune response, which fails to evolve into adaptive immunity and to eradicate infection. Chronic infections result in lung damage and patient morbidity. Notably, ceramide content in mucosa airways is higher in CF mouse models and in patients than in control mice or healthy subjects.

Methods

The therapeutic potential of myriocin, an inhibitor of the sphingolipid de novo synthesis rate limiting enzyme (Serine Palmitoyl Transferase, SPT),was investigated in CF cells and mice models.

Results

We treated CF human respiratory epithelial cells with myriocin, This treatment resulted in reduced basal, as well as TNFα-stimulated, inflammation. In turn, TNFα induced an increase in SPT in these cells, linking de novo synthesis of ceramide to inflammation. Furthermore, myriocin-loaded nanocarrier, injected intratrachea prior to P. aeruginosa challenge, enabled a significant reduction of lung infection and reduced inflammation.

Conclusions

The presented data suggest that de novo ceramide synthesis is constitutively enhanced in CF mucosa and that it can be envisaged as pharmacological target for modulating inflammation and restoring effective innate immunity against acute infection.

General significance

Myriocin stands as a powerful immunomodulatory agent for inflammatory and infectious diseases.  相似文献   
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