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991.
Pedro G. Nachtigall Marcos C. Dias Robson F. Carvalho Cesar Martins Danillo Pinhal 《PloS one》2015,10(3)
A class of small non-coding RNAs, the microRNAs (miRNAs), has been shown to be essential for the regulation of specific cell pathways, including skeletal muscle development, maintenance and homeostasis in vertebrates. However, the relative contribution of miRNAs for determining the red and white muscle cell phenotypes is far from being fully comprehended. To better characterize the role of miRNA in skeletal muscle cell biology, we investigated muscle-specific miRNA (myomiR) signatures in Nile tilapia fish. Quantitative (RT-qPCR) and spatial (FISH) expression analyses revealed a highly differential expression (forty-four-fold) of miR-499 in red skeletal muscle compared to white skeletal muscle, whereas the remaining known myomiRs were equally expressed in both muscle cell types. Detailed examination of the miR-499 targets through bioinformatics led us to the sox6 and rod1 genes, which had low expression in red muscle cells according to RT-qPCR, FISH, and protein immunofluorescence profiling experiments. Interestingly, we verified that the high expression of miR-499 perfectly correlates with a low expression of sox6 and rod1 target genes, as verified by a distinctive predominance of mRNA destabilization and protein translational decay to these genes, respectively. Through a genome-wide comparative analysis of SOX6 and ROD1 protein domains and through an in silico gene regulatory network, we also demonstrate that both proteins are essentially similar in vertebrate genomes, suggesting their gene regulatory network may also be widely conserved. Overall, our data shed light on the potential regulation of targets by miR-499 associated with the slow-twitch muscle fiber type phenotype. Additionally the results provide novel insights into the evolutionary dynamics of miRNA and target genes enrolled in a putative constrained molecular pathway in the skeletal muscle cells of vertebrates. 相似文献
992.
Norinne Lacerda-Queiroz Fatima Brant David Henrique Rodrigues Juliana Priscila Vago Milene Alvarenga Rachid Lirlandia Pires Sousa Mauro Martins Teixeira Antonio Lucio Teixeira 《PloS one》2015,10(3)
Experimental cerebral malaria (ECM) is characterized by a strong immune response, with leukocyte recruitment, blood-brain barrier breakdown and hemorrhage in the central nervous system. Phosphatidylinositol 3-kinase γ (PI3Kγ) is central in signaling diverse cellular functions. Using PI3Kγ-deficient mice (PI3Kγ-/-) and a specific PI3Kγ inhibitor, we investigated the relevance of PI3Kγ for the outcome and the neuroinflammatory process triggered by Plasmodium berghei ANKA (PbA) infection. Infected PI3Kγ-/- mice had greater survival despite similar parasitemia levels in comparison with infected wild type mice. Histopathological analysis demonstrated reduced hemorrhage, leukocyte accumulation and vascular obstruction in the brain of infected PI3Kγ-/- mice. PI3Kγ deficiency also presented lower microglial activation (Iba-1+ reactive microglia) and T cell cytotoxicity (Granzyme B expression) in the brain. Additionally, on day 6 post-infection, CD3+CD8+ T cells were significantly reduced in the brain of infected PI3Kγ-/- mice when compared to infected wild type mice. Furthermore, expression of CD44 in CD8+ T cell population in the brain tissue and levels of phospho-IkB-α in the whole brain were also markedly lower in infected PI3Kγ-/- mice when compared with infected wild type mice. Finally, AS605240, a specific PI3Kγ inhibitor, significantly delayed lethality in infected wild type mice. In brief, our results indicate a pivotal role for PI3Kγ in the pathogenesis of ECM. 相似文献
993.
Laura Taguchi Nathalia M. Pinheiro Clarice R. Olivo Alessandra Choqueta-Toledo Simone S. Grecco Fernanda D.T.Q.S. Lopes Luciana C. Caperuto Mílton A. Martins Iolanda F.L.C. Tiberio Niels O. Camara Jo?o Henrique G. Lago Carla M. Prado 《Respiratory research》2015,16(1)
BackgroundPulmonary emphysema is characterized by irreversible airflow obstruction, inflammation, oxidative stress imbalance and lung remodeling, resulting in reduced lung function and a lower quality of life. Flavonoids are plant compounds with potential anti-inflammatory and antioxidant effects that have been used in folk medicine. Our aim was to determine whether treatment with sakuranetin, a flavonoid extracted from the aerial parts of Baccharis retusa, interferes with the development of lung emphysema.MethodsIntranasal saline or elastase was administered to mice; the animals were then treated with sakuranetin or vehicle 2 h later and again on days 7, 14 and 28. We evaluated lung function and the inflammatory profile in bronchoalveolar lavage fluid (BALF). The lungs were removed to evaluate alveolar enlargement, extracellular matrix fibers and the expression of MMP-9, MMP-12, TIMP-1, 8-iso-PGF-2α and p65-NF-κB in the fixed tissues as well as to evaluate cytokine levels and p65-NF-κB protein expression.ResultsIn the elastase-treated animals, sakuranetin treatment reduced the alveolar enlargement, collagen and elastic fiber deposition and the number of MMP-9- and MMP-12-positive cells but increased TIMP-1 expression. In addition, sakuranetin treatment decreased the inflammation and the levels of TNF-α, IL-1β and M-CSF in the BALF as well as the levels of NF-κB and 8-iso-PGF-2α in the lungs of the elastase-treated animals. However, this treatment did not affect the changes in lung function.ConclusionThese data emphasize the importance of oxidative stress and metalloproteinase imbalance in the development of emphysema and suggest that sakuranetin is a potent candidate that should be further investigated as an emphysema treatment. This compound may be useful for counteracting lung remodeling and oxidative stress and thus attenuating the development of emphysema.
Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0233-3) contains supplementary material, which is available to authorized users. 相似文献994.
995.
996.
Ana Flávia Mar?al-Pessoa Carmen Lucia Bassi-Branco Cristiana dos Santos Barbosa Salvatierra Luiz Fabrizio Stoppiglia Letícia Martins Ignacio-Souza Sílvia Regina de Lima Reis Roberto Vilela Veloso Marise Auxiliadora de Barros Reis Everardo Magalh?es Carneiro Antonio Carlos Boschero Vanessa Cristina Arantes Márcia Queiroz Latorraca 《Biological research》2015,48(1)
Background
Gap junctions between β-cells participate in the precise regulation of insulin secretion. Adherens junctions and their associated proteins are required for the formation, function and structural maintenance of gap junctions. Increases in the number of the gap junctions between β-cells and enhanced glucose-stimulated insulin secretion are observed during pregnancy. In contrast, protein restriction produces structural and functional alterations that result in poor insulin secretion in response to glucose. We investigated whether protein restriction during pregnancy affects the expression of mRNA and proteins involved in gap and adherens junctions in pancreatic islets. An isoenergetic low-protein diet (6% protein) was fed to non-pregnant or pregnant rats from day 1–15 of pregnancy, and rats fed an isocaloric normal-protein diet (17% protein) were used as controls.Results
The low-protein diet reduced the levels of connexin 36 and β-catenin protein in pancreatic islets. In rats fed the control diet, pregnancy increased the levels of phospho-[Ser279/282]-connexin 43, and it decreased the levels of connexin 36, β-catenin and beta-actin mRNA as well as the levels of connexin 36 and β-catenin protein in islets. The low-protein diet during pregnancy did not alter these mRNA and protein levels, but avoided the increase of levels of phospho-[Ser279/282]-connexin 43 in islets. Insulin secretion in response to 8.3 mmol/L glucose was higher in pregnant rats than in non-pregnant rats, independently of the nutritional status.Conclusion
Short-term protein restriction during pregnancy prevented the Cx43 phosphorylation, but this event did not interfer in the insulin secretion. 相似文献997.
D. Gaspar A. C Pimentel M. J. Mendes T. Mateus B. P. Falcão J. P. Leitão J. Soares A. Araújo A. Vicente S. A. Filonovich H. Águas R. Martins I. Ferreira 《Plasmonics (Norwell, Mass.)》2014,9(5):1015-1023
Silver (Ag) and tin (Sn) nanoparticles (NPs) were deposited by thermal evaporation onto heated glass substrates with a good control of size, shape and surface coverage. This process has the advantage of allowing the fabrication of thin-film solar cells with incorporated NPs without vacuum break, since it does not require chemical processes or post-deposition annealing. The X-ray diffraction, TEM and SEM properties are correlated with optical measurements and amorphous silicon hydrogenated (a-Si:H) films deposited on top of both types of NPs show enhanced absorbance in the near-infrared. The results are interpreted with electromagnetic modelling performed with Mie theory. A broad emission in the near-infrared region is considerably increased after covering the Ag nanoparticles with an a-Si:H layer. Such effect may be of interest for possible down-conversion mechanisms in novel photovoltaic devices. 相似文献
998.
Gilberto Martins Luciana Peixoto António G. Brito Regina Nogueira 《Reviews in Environmental Science and Biotechnology》2014,13(3):265-275
All restoration strategies to mitigate eutrophication depend on the success of phosphorus (P) removal from the water body. Therefore, the inputs from the watershed and from the enriched sediments, that were the sink of most P that has been discharged in the water body, should be controlled. In sediments, iron (hydr)oxides minerals are potent repositories of P and the release of P into the water column may occur upon dissolution of the iron (hydr)oxides mediated by iron reducing bacteria. Several species of these bacteria are also known as electroactive microorganisms and have been recently identified in lake sediments. This capacity of bacteria to transfer electrons to electrodes, producing electricity from the oxidation of organic matter, might play a role on P release in sediments. In the present work it is discussed the relationship between phosphorus and iron cycling as well as the application of an electrode to work as external electron acceptor in sediments, in order to prevent metal bound P dissolution under anoxic conditions. 相似文献
999.
Flávio Ricardo Guilherme Carlos Alexandre Molena-Fernandes Luzia Jaeger Hintze Maria Teresa Martins Fávero Roberto Kenji Nakamura Cuman Wilson Rinaldi 《PloS one》2014,9(11)
ObjectiveTo identify the prevalence of hypertriglyceridemic waist (HTW) phenotype and its association with metabolic abnormalities in schoolchildren.MethodsA cross-sectional study, with a sample of 241 students aged 10 to 14 years from public schools (4 schools) and private (2 schools) from Paranavai town, in Parana State, Brazil. Anthropometric variables (weight, height, waist circumference) and levels of triglycerides, total cholesterol, HDL-C, non-HDL and LDL-C were analyzed. In statistical tests of Pearson partial correlation and multivariate logistic regression, considering p<0,05.ResultsThe prevalence of HTW was 20,7% among schoolchildren, 14,1% in males and 6,6% among females with higher proportions aged 10–12 years old. Multivariate analysis indicated that the students who attended private schools were nearly three times more likely (95% CI: 1,2–5,6), to be diagnosed with HTW compared with those who attended public schools (p = 0,006), and LDL-C was the only metabolic variable positively associated with the outcome (p = 0,001), where the students categorized with elevated serum levels had odds 4,2 times (95% CI: 1,6–10,9) having the HTW compared to students in appropriate levels.ConclusionThis study showed higher prevalence of hypertriglyceridemic waist phenotype in students when compared to prospective studies in Brazil and worldwide. It also showed that the only metabolic alteration associated with HTW phenotype was LDL-C (low density lipoprotein). 相似文献
1000.
Tomàs M. Pérez-Porcuna Carlos Ascaso Adriana Malheiro Rosa Abellana Marilaine Martins José Felipe Jardim Sardinha Patricia Quincó Irineide Assump??o Antunes Marlucia da Silva Garrido Samira Bührer-Sékula Flor Ernestina Martinez-Espinosa 《PloS one》2014,9(5)