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1.

Background

Environmental challenges might affect the maternal organism and indirectly affect the later ontogeny of the progeny. We investigated the cross-generation impact of a moderate heat challenge in chickens. We hypothesized that a warm temperature–within the thermotolerance range- would affect the hormonal environment provided to embryos by mothers, and in turn, affect the morphology and behavioral phenotype of offspring.

Methodology/Principal Findings

Laying hens were raised under a standard thermal condition at 21°C (controls) or 30°C (experimental) for 5 consecutive weeks. A significant increase was observed in the internal temperature of hens exposed to the warm treatment; however plasma corticosterone levels remained unaffected. The laying rate was not affected, but experimental hens laid lighter eggs than the controls during the treatment. As expected, the maternal thermal environment affected yolk hormone contents. Eggs laid by the experimental hens showed significantly higher concentrations of yolk progesterone, testosterone, and estradiol. All chicks were raised under standard thermal conditions. The quality of hatchlings, growth, feeding behavior and emotional reactivity of chicks were analyzed. Offspring of experimental hens (C30 chicks) were lighter but obtained better morphological quality scores at hatching than the controls (C21 chicks). C30 chicks expressed lesser distress calls when exposed to a novel food. Unlike C21 chicks, C30 chicks expressed no preference for energetic food.

Conclusion/Significance

Our findings suggest that moderate heat challenge triggers maternal effects and modulate the developmental trajectory of offspring in a way that may be adaptive. This suggests that the impact of heat challenges on captive or wild populations might have a cross-generation effect.  相似文献   
2.
In the present study, we surveyed the distribution and diversity of fungal assemblages associated with 10 species of marine animals from Antarctica. The collections yielded 83 taxa from 27 distinct genera, which were identified using molecular biology methods. The most abundant taxa were Cladosporium sp. 1, Debaryomyces hansenii, Glaciozyma martinii, Metschnikowia australis, Pseudogymnoascus destructans, Thelebolus cf. globosus, Pseudogymnoascus pannorum, Tolypocladium tundrense, Metschnikowia australis, and different Penicillium species. The diversity, richness, and dominance of fungal assemblages ranged among the host; however, in general, the fungal community, which was composed of endemic and cold-adapted cosmopolitan taxa distributed across the different sites of Antarctic Peninsula, displayed high diversity, richness, and dominance indices. Our results contribute to knowledge about fungal diversity in the marine environment across the Antarctic Peninsula and their phylogenetic relationships with species that occur in other cold, temperate, and tropical regions of the World. Additionally, despite their extreme habitats, marine Antarctic animals shelter cryptic and complex fungal assemblages represented by endemic and cosmopolitan cold-adapted taxa, which may represent interesting models to study different symbiotic associations between fungi and their animal hosts in the extreme conditions of Antarctica.  相似文献   
3.
Paracoccidioides brasiliensis rarely shows bone marrow involvement and its response to treatment with itraconazole in children needs further assessment. We describe here a child with a juvenile disseminated form of paracoccidioidomycosis, which showed reticuloendothelial system involvement and the presence of Paracoccidioides brasiliensis in the bone marrow. The patient showed an effective and rapid response to itraconazole therapy.  相似文献   
4.
G-protein-coupled receptors (GPCRs) represent approximately 3% of human proteome and the most prominent class of pharmacological targets. Despite their important role in many functions, only the X-ray structures of rhodopsin, and more recently of the β1- and β2-adrenergic receptors, have been resolved. Structural studies of GPCRs require that several tedious preliminary steps be fulfilled before setting up the first crystallization experiments: protein expression, detergent solubilization, purification, and stabilization. Here we report on screening expression conditions of approximately 100 GPCRs in Escherichia coli with a view to obtain large amounts of inclusion bodies, a prerequisite to the subsequent refolding step. A set of optimal conditions, including appropriate vectors (Gateway pDEST17oi), strain (C43), and fermentation at high optical density, define the best first instance choice. Beyond this minimal setting, however, the rate of success increases significantly with the number of conditions tested. In contrast with experiments based on a single GPCR expression, our approach provides statistically significant results and indicates that up to 40% of GPCRs can be expressed as inclusion bodies in quantities sufficient for subsequent refolding, solubilization, and purification.  相似文献   
5.
Aquatic herbaceous macrophytes grow in profusion in the Amazon fertile varzea floodplains. A large number of species occur but only a few are particularly abundant, supporting food chains, contributing substantially to carbon and nutrient cycles. Their growth and role in the ecosystem depend, among other, on its life cycles and habits, floating or semi-aquatic. Although in the last decades, petroliferous activity intensified in the Central Amazon region and so did oil spills, the effect of petroleum on the native aquatic plants is unknown. The present study was designed to test experimentally the survival and morpho-anatomical modifications of the free floating water hyacinth Eichhornia crassipes and the semi-aquatic grass Echinochloa polystachya to 10 different concentrations of crude oil. Higher concentrations of crude oil caused the mortality in both species; however, lethal dose (LD50) values showed that E. polystachya was more sensitive than E. crassipes. Despite the higher tolerance of E. crassipes, the inhibition of root and leaf growth as well as anatomical modifications in leaves were registered in higher concentrations. Additionally, the oil caused a reduction in leaf numbers in both species. Although mortality of the floating species was lower, it may increases over time, since important alterations in morphology and anatomy occurred. These results show that oil spills in the Amazon varzea can cause severe alterations in the aquatic flora and in the floodplain dynamics.  相似文献   
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ObjectivesTo explore how GPs conceptualise advance care planning (ACP), based on their experiences with ACP in their practice.MethodsFive focus groups were held with 36 GPs. Discussions were analysed using a constant comparative method.ResultsFour overarching themes in the conceptualisations of ACP were discerned: (1) the organisation of professional care required to meet patients’ needs, (2) the process of preparing for death and discussing palliative care options, (3) the discussion of care goals and treatment decisions, (4) the completion of advance directives. Within these themes, ACP was both conceptualised in terms of content of ACP and/or in terms of tasks for the GP. A specific task that was mentioned throughout the discussion of the four different themes was (5) the task of actively initiating ACP by the GP versus passively waiting for patients’ initiation.ConclusionsThis study illustrates that GPs have varying conceptualisations of ACP, of which some are more limited to specific aspects of ACP. A shared conceptualisation and agreement on the purpose and goals of ACP is needed to ensure successful implementation, as well as a systematic integration of ACP in routine practice that could lead to a better uptake of all the important elements of ACP.  相似文献   
9.
Upon contact with airway epithelial cells, mycobacteria activate several signal transduction events that are required for induction of NF-kappaB-dependent chemokine gene expression. However, downstream signaling pathways, especially that of Ca(2+)-dependent protein kinase C alpha (PKCalpha), and in particular, the identity of the IKKalphabeta signal pathway for CXCL8 secretion in Mycobacterium bovis BCG-induced epithelial cells are still unknown. In this study, we demonstrated that the phosphoinositide-phospholipase C (PI-PLC) downstream signaling pathway is involved in M. bovis BCG-induced CXCL8 release, since A549 cells pretreated with U73122, a PI-PLC inhibitor, inhibited CXCL8 release, whereas U73343 the inactive analog had no effect. In addition, our results demonstrated that M. bovis BCG-induced CXCL8 production by A549 cells was significantly blocked by using neomycin (another well-described inhibitor of PI-PLC with a different mechanism of action), Ro-32-0432 and Ro-31-8220 (two PKCalpha inhibitors), PP1 and PP2 (two potent and selective inhibitors of the Src-family tyrosine kinases), and Bay 11-7082 (an IkappaB phosphorylation inhibitor). We also demonstrated that M. bovis BCG can rapidly induce translocation of PKCalpha from the cytosol to the membrane, and that treatment of cells with M. bovis BCG caused time-dependent increases in phosphorylation of c-Src at tyrosine 416. Finally, our studies revealed that M. bovis BCG induced the association of c-Src and IKKalphabeta during the interaction of PKCalpha and IKKalphabeta. Altogether, these results represent the first evidence to date suggesting that M. bovis BCG activates the PI-PLC/PKCalpha/c-Src/IKKalphabeta signaling pathway to induce CXCL8 release in human epithelial cells.  相似文献   
10.
The concept of pollination syndromes has been widely questioned, since plant–pollinator interactions have proved to be more generalist than was previously thought. We examined whether the network of a tropical high‐altitude grassland contained groups of plants and pollinators that interact preferentially with each other. A general binary matrix was created. To assess the robustness of myophily, in all analyses we considered: 1) the whole network, 2) the network after the wasps were removed, and 3) the network after the flies were removed. For each network we evaluated whether: 1) the observed interactions were more related to syndromes than expected by chance, compared to an expected matrix; 2) there was a modular structure; 3) the modules found were more related to syndromes than expected by chance, compared to another expected matrix; 4) the syndromes were equally robust. For this analysis, the general matrix was subdivided into smaller matrices that included each pollination syndrome separately. To test the influence of the functional groups of pollinators and the phylogeny of plants, in addition to the general matrix, we also considered the first expected matrix, a quantitative functional group and a plant phylogeny matrix. The pollination syndromes determined the pattern of interactions in the network: 69% of the total interactions resulted from the functional group of pollinators predicted by the plant syndrome. The network showed greater modularity (13 modules) than expected by chance, mostly consisting of the expected functional groups of pollinators and plant syndromes. The modules were associated with pollination syndromes more than was predicted by chance. Most of the variation in interactions was explained by functional groups of pollinators or by plant syndromes. Plant phylogeny did not account for a significant amount of variation in the interactions. Our findings support the concept of pollination syndromes. However, the interactions were not equally predicted by different pollination syndromes, and the accuracy of the prediction was strongest for ornithophily and melittophily.  相似文献   
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