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731.
Jesús Hernndez Eneida Soto-Canevett Araceli Pinelli-Saavedra Mnica Resendiz Silvia Y. Moya-Camarena Kirk C. Klasing 《Veterinary immunology and immunopathology》2009,131(1-2):9-16
In order to analyze the effect of vitamin E on Th1 and Th2 cytokine production, porcine peripheral blood mononuclear cells (PBMC) were isolated from healthy pigs (n = 8) and cultured with either 0, 10, 50, or 100 μM of vitamin E (α-tocopherol). PBMC were stimulated with PHA for either, 24 h to determine: (a) the concentration of tocopherol incorporated into the cell membrane, (b) cytokine production and (c) Th1 and Th2 regulators gene expression; or 72 h to determine the proliferation of PBMC. Vitamin E was incorporated into the PBMC in a dose dependent manner, giving as a result a high proliferation of cells irrespective of the dose of vitamin E used. Regarding cytokine production, vitamin E consistently decreases the mRNA expression and the percentage of cells producing IL-10. Vitamin E did not influence the production of IFN-γ but the lowest level of vitamin E (10 μM) was sufficient to maximally increase the proportion of cells producing IL-2, to diminish IL-4, and discreetly increase the mRNA expression of TBX21 vs. GATA3. In conclusion, our results revealed that vitamin E is able to suppress IL-10 production and to influence the production of IL-2, IL-4, and maybe TBX21. Vitamin E clearly has immunomodulatory effects, though further work in vivo to determine the physiological nature of these effects is warranted. 相似文献
732.
Roberta Teta Germana Esposito Karishma Kundu Mariano Stornaiuolo Silvia Scarpato Antonino Pollio Valeria Costantino 《Marine drugs》2022,20(4)
In this study, a strain of Anabaena flos-aquae UTEX 1444 was cultivated in six different concentrations of iron (III). Cultures were extracted with organic solvents and analyzed using our dereplication strategy, based on the combined use of high-resolution tandem mass spectrometry and molecular networking. The analysis showed the presence of the siderophores’ family, named synechobactins, only in the zero iron (III) treatment culture. Seven unknown synechobactin variants were present in the extract, and their structures have been determined by a careful HRMS/MS analysis. This study unveils the capability of Anabaena flos-aquae UTEX 1444 to produce a large array of siderophores and may be a suitable model organism for a sustainable scale-up exploitation of such bioactive molecules, for the bioremediation of contaminated ecosystems, as well as in drug discovery. 相似文献
733.
- Group membership is a key attribute of animal societies and central to the study of social structure in several taxa. However, social structure analyses are sensitive to the way data are collected and associations defined.
- In this study, a time–space method was used to investigate the social structure of common bottlenose dolphins Tursiops truncatus observed and photographed across 7 years in the semi-enclosed Gulf of Corinth, Greece. Instead of adopting traditional group definitions, individuals were considered as being members of the same group if photographed within a specific time and space window. This approach can be applied post hoc across studies and can offer advantages under challenging sampling conditions (e.g. when dealing with groups spread over vast areas or when group membership is otherwise hard to assess).
- Dolphins were mostly found around coastal cage aquaculture facilities farming European sea bass Dicentrarchus labrax and gilthead seabream Sparus aurata.
- Dolphins formed clusters largely or entirely composed of individuals of the same sex, suggestive of sex-based homophily. Habitat partitioning was not detected: there was substantial spatial overlap among dolphin clusters, with all individuals using a relatively small area in the northern portion of the Gulf, where most of the productive fish farms were located. Associations between females were stronger than those between males, and daughters tended to stay in the group of their mothers.
- Sex-based social clustering may allow females and calves to limit interactions with potentially aggressive males, while individuals of both sexes benefit from prey concentrated around fish farms.
- Adaptation to foraging around farms can result in trade-offs between the costs and benefits of nourishment and social interaction. This may have both positive or negative effects on the animals that should be considered in the context of ensuring their favourable conservation status.