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181.
Vinolo MA Rodrigues HG Hatanaka E Sato FT Sampaio SC Curi R 《The Journal of nutritional biochemistry》2011,22(9):849-855
Short chain fatty acids (SCFAs) are fermentation products of anaerobic bacteria. More than just being an important energy source for intestinal epithelial cells, these compounds are modulators of leukocyte function and potential targets for the development of new drugs. The aim of this study was to evaluate the effects of SCFAs (acetate, propionate and butyrate) on production of nitric oxide (NO) and proinflammatory cytokines [tumor necrosis factor α (TNF-α) and cytokine-induced neutrophil chemoattractant-2 (CINC-2αβ)] by rat neutrophils. The involvement of nuclear factor κB (NF-κB) and histone deacetylase (HDAC) was examined. The effect of butyrate was also investigated in vivo after oral administration of tributyrin (a pro-drug of butyrate). Propionate and butyrate diminished TNF-α, CINC-2αβ and NO production by LPS-stimulated neutrophils. We also observed that these fatty acids inhibit HDAC activity and NF-κB activation, which might be involved in the attenuation of the LPS response. Products of cyclooxygenase and 5-lipoxygenase are not involved in the effects of SCFAs as indicated by the results obtained with the inhibitors of these enzymes. The recruitment of neutrophils to the peritonium after intraperitoneal administration of a glycogen solution (1%) and the ex vivo production of cytokines and NO by neutrophils were attenuated in rats that previously received tributyrin. These results argue that this triglyceride may be effective in the treatment of inflammatory conditions. 相似文献
182.
The taxonomic relationships among the four genera of the Atelidae family, Alouatta (Howler), Ateles (Spider), Lagothrix (Woolly) and Brachyteles (Muriqui), have been the subject of great debate. In general, almost all authors agree with the assignment of Howler monkeys
as the basal genus, either in its own tribe Alouattini or in the subfamily Alouattinae, but they disagree on the associations
among the other members of the family. Muriquis have been grouped with Spider monkeys based on the fact that they share various
behavioral and morphological characteristics. Cladistic analyses using morphological, biochemical, karyotype and behavioral
characteristics depicted a phylogenetic tree that places Howler as the basal genus and the remaining genera in an unresolved
politomy. More recent studies using molecular data have suggested that Muriqui and Woolly monkeys are sister groups. However,
a recent study based on nuclear and mtDNA argued that politomy is what best represents the relationships among Spider, Woolly
and Muriqui. To contribute to this debate we have added new data from two nuclear genes, Transferrin and von Willebrand Factor,
and using an alignment of 17,997 bp we demonstrate that a total analysis strongly supports the Muriqui-Woolly clade. A gene-to-gene
approach showed that four of the eight nuclear genes provide support for the Muriqui-Woolly clade, two strongly and two moderately,
while none of the eight genes provide support for any alternative arrangement. The mitochondrial genes were not able to resolve
the politomy. A possible reason for the difficulty in resolving atelid relationships may be the short period of time separating
each cladogenetic event in the evolutionary process that shaped this family. 相似文献
183.
The goal of restoration is to accelerate ecosystem recovery, but in ecosystems that naturally regenerate rapidly restoration techniques need to be selected carefully to facilitate rather than impede natural recovery. We compared the effects of five restoration techniques, such as plowing the soil, removing grasses, adding forest litter, seeding, and planting nursery‐growing seedlings, on the regeneration of seasonal deciduous forest trees in four abandoned pastures in central Brazil. We monitored all woody stems immediately prior to treatments and again 14 months after the treatments. We recorded an average of 16,663 tree stems per hectare and a total of 83 species before implementing treatments. Planting strongly increased species richness; adding litter and seeding had weaker positive effects on richness; and plowing and grass removal had no effect. Plowing substantially reduced the density of naturally established stems. Despite the high survival of planted seedlings, stem density in planting treatments did not change because the tractor and digging holes to plant seedlings caused mortality of naturally regenerating seedlings. Tree stems grew more in the grass release plots than in the control plots. Our results suggest that early succession of seasonal deciduous forest in pastures in the region studied does not need to be stimulated once the perturbation is stopped and that intensive restoration efforts may actually slow recovery. We recommend only enrichment planting of seedlings that are not able to resprout. 相似文献
184.
Inês Catry Ana Sampaio Mnica C. Silva Francisco Moreira Aldina M. A. Franco Teresa Catry 《Ibis》2019,161(2):272-285
Diet studies are crucial for understanding the ecology and evolution of species, as well as for establishing appropriate conservation and management strategies. However, they remain methodologically challenging due to variation between seasons, sites, sexes or age groups and even variation between individuals. Due to method‐specific characteristics and biases, a combination of existing techniques can overcome the inherent limitations of each technique and provide a more accurate and broad picture of species’ food preferences. Here, we examine diet information obtained using three different assessment methods to better understand the trophic ecology of the European Roller Coracias garrulus, a species targeted by conservation measures in Europe. First, we analysed regurgitated pellets and video‐recordings to report the diet composition of adult and nestling Rollers, respectively. Secondly, we used stable isotope analysis (SIA) to investigate adult sexual diet segregation as well as to confirm the main findings regarding adult and nestling diets obtained through conventional methods. Based on the analysis of pellets, the diet of adult Rollers was dominated by Coleoptera, whereas camera images revealed that the diet of nestlings was dominated by Orthoptera, mainly grasshoppers and bush crickets. Blood isotopic signatures of adult and nestling Rollers confirmed the results obtained through pellet and video‐recording techniques. Of the three methods, pellet analysis provided the most comprehensive trophic information regarding the detectable prey spectrum and prey species contribution, as well as basic diet information for the SIA. Our results also highlight the potential of SIA for assessing intraspecific variation in diet by sampling individuals of known age and sex, which is often unfeasible through conventional approaches. SIA analysis showed no differences in δ13C and δ15N ratios of blood between males and females and a high degree of overlap amongst isotopic niches, suggesting no sex‐specific partitioning in resource use. Overall, we showed that the combination of different methods could be used to gain new and clearer insights into avian trophic ecology that are essential for informing habitat management aiming to improve availability of foraging resources. 相似文献
185.
Octavio Ferreira de Matos Diego Valente Pereira Jamerson Aguiar‐Santos Andr da Silva Sampaio Carlos Edwar de Carvalho Freitas Flvia Kelly Siqueira‐Souza 《Zeitschrift fur angewandte Ichthyologie》2019,35(3):799-801
Parameters of the length‐weight relationship (LWR) were calculated for five fish species from Amazon Basin. Samplings were carried out in ten lakes of the Solimões River floodplains during the four seasons of the hydrological cycle: rising water, high water, receding water, and low water, during two periods. The first period of eight years included samplings performed from 2001 to 2008 and the second sampling period of two years was from 2012 to 2013. Specimens were captured using gillnets (mesh sizes ranging from 30 to 120 mm between opposite knots) and standardized dimension of 20 m in length × 2 m in height. This study provides the LWR parameters for Acarichthys heckelii, Leporinus trifasciatus, Brycon amazonicus, Curimatella meyeri and Osteoglossum bicirrhosum. 相似文献
186.
187.
I. B. Schmidt D. I. de Urzedo F. C. M. Pia‐Rodrigues D. L. M. Vieira G. M. de Rezende A. B. Sampaio R. G. P. Junqueira 《Plant biology (Stuttgart, Germany)》2019,21(3):389-397
- Large‐scale restoration programmes in the tropics require large volumes of high quality, genetically diverse and locally adapted seeds from a large number of species. However, scarcity of native seeds is a critical restriction to achieve restoration targets.
- In this paper, we analyse three successful community‐based networks that supply native seeds and seedlings for Brazilian Amazon and Cerrado restoration projects. In addition, we propose directions to promote local participation, legal, technical and commercialisation issues for up‐scaling the market of native seeds for restoration with high quality and social justice.
- We argue that effective community‐based restoration arrangements should follow some principles: (i) seed production must be based on real market demand; (ii) non‐governmental and governmental organisations have a key role in supporting local organisation, legal requirements and selling processes; (iii) local ecological knowledge and labour should be valued, enabling local communities to promote large‐scale seed production; (iv) applied research can help develop appropriate techniques and solve technical issues.
- The case studies from Brazil and principles presented here can be useful for the up‐scaling restoration ecology efforts in many other parts of the world and especially in tropical countries where improving rural community income is a strategy for biodiversity conservation and restoration.
188.
Downstairs gene flow: the effects of a linear sequence of waterfalls on the only population of the endangered minnow Astyanax xavante 下载免费PDF全文
K. V. Reis P. C. Venere I. Sampaio P. S. Rêgo M. Vallinoto I. L. Souza 《Journal of fish biology》2015,87(3):754-762
The aim of this study was to estimate the genetic diversity and structure of the only known population of minnow Astyanax xavante, which inhabits a stretch of river including several waterfalls. The FST values among the samples were not significant, except between two populations separated by a 30 m waterfall. Nevertheless, haplotype and nucleotide diversity increased in the downstream direction, indicating that gene flow is unidirectional, which indicates this genetic pattern as downstairs gene flow, as it has the effect of increasing genetic diversity in the downstream direction. 相似文献
189.
Pedro Araújo Igor Cesarino Juliana Lischka Sampaio Mayer Ilse Fernanda Ferrari Eduardo Kiyota Alexandra Christine Helena Frankland Sawaya Adriana Franco Paes Leme Paulo Mazzafera 《Physiologia plantarum》2014,152(1):17-31
Recalcitrance of plant biomass is closely related to the presence of the phenolic heteropolymer lignin in secondary cell walls, which has a negative effect on forage digestibility, biomass‐to‐biofuels conversion and chemical pulping. The genus Eucalyptus is the main source of wood for pulp and paper industry. However, when compared to model plants such as Arabidopsis thaliana and poplar, relatively little is known about lignin biosynthesis in Eucalyptus and only a few genes were functionally characterized. An efficient, fast and inexpensive in vitro system was developed to study lignification in Eucalyptus globulus and to evaluate the potential role of candidate genes in this biological process. Seedlings were grown in four different conditions, in the presence or absence of light and with or without sucrose in the growth medium, and several aspects of lignin metabolism were evaluated. Our results showed that light and, to a lesser extent, sucrose induced lignin biosynthesis, which was followed by changes in S/G ratio, lignin oligomers accumulation and gene expression. In addition, higher total peroxidase activity and differential isoperoxidase profile were observed when seedlings were grown in the presence of light and sucrose. Peptide sequencing allowed the identification of differentially expressed peroxidases, which can be considered potential candidate class III peroxidases involved in lignin polymerization in E. globulus. 相似文献
190.
Tânia L. Costa Everardo V. S. B. Sampaio Margareth F. Sales Luciano J. O. Accioly Tiago D. Althoff Frans G. C. Pareyn Eliza R. G. M. Albuquerque Rômulo S. C. Menezes 《Plant and Soil》2014,378(1-2):113-123