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81.
Adriana Fernanda Vizuete Daniela Fraga de Souza Maria Cristina Guerra Cristiane Batassini Márcio Ferreira Dutra Caren Bernardi Ana Paula Costa Carlos-Alberto Gonçalves 《Life sciences》2013,92(17-19):923-928
AimsWe investigated the effects of ketogenic diet (KD) on levels of tumor necrosis factor alpha (TNF-α, a classical pro-inflammatory cytokine), BDNF (brain-derived neurotrophic factor, commonly associated with synaptic plasticity), and S100B, an astrocyte neurotrophic cytokine involved in metabolism regulation.Main methodsYoung Wistar rats were fed during 8 weeks with control diet or two KD, containing different proportions of omega 6 and omega 3 polyunsaturated fatty acids. Contents of TNF-α, BDNF and S100B were measured by ELISA in two brain regions (hippocampus and striatum) as well as blood serum and cerebrospinal fluid.Key findingsOur data suggest that KD was able to reduce the levels of BDNF in the striatum (but not in hippocampus) and S100B in the cerebrospinal fluid of rats. These alterations were not affected by the proportion of polyunsaturated fatty acids offered. No changes in S100B content were observed in serum or analyzed brain regions. Basal TNF-α content was not affected by KD.SignificanceThese findings reinforce the importance of this diet as an inductor of alterations in the brain, and such changes might contribute to the understanding of the effects (and side effects) of KD in brain disorders. 相似文献
82.
Marina Azevêdo Souza Susana Johann Luciana Alves Rodrigues dos Santos Lima Fernanda Fraga Campos Isolda Castro Mendes Heloisa Beraldo Elaine Maria de Souza-Fagundes Patrícia Silva Cisalpino Carlos Augusto Rosa Tania Maria de Almeida Alves Nívea Pereira de Sá Carlos Leomar Zani 《Memórias do Instituto Oswaldo Cruz》2013,108(3):342-351
Lapachol was chemically modified to obtain its thiosemicarbazone and semicarbazone derivatives. These compounds were tested for antimicrobial activity against several bacteria and fungi by the broth microdilution method. The thiosemicarbazone and semicarbazone derivatives of lapachol exhibited antimicrobial activity against the bacteria Enterococcus faecalis and Staphylococcus aureus with minimal inhibitory concentrations (MICs) of 0.05 and 0.10 µmol/mL, respectively. The thiosemicarbazone and semicarbazone derivatives were also active against the pathogenic yeast Cryptococcus gattii (MICs of 0.10 and 0.20 µmol/mL, respectively). In addition, the lapachol thiosemicarbazone derivative was active against 11 clinical isolates of Paracoccidioides brasiliensis, with MICs ranging from 0.01-0.10 µmol/mL. The lapachol-derived thiosemicarbazone was not cytotoxic to normal cells at the concentrations that were active against fungi and bacteria. We synthesised, for the first time, thiosemicarbazone and semicarbazone derivatives of lapachol. The MICs for the lapachol-derived thiosemicarbazone against S. aureus, E. faecalis, C. gattii and several isolates of P. brasiliensis indicated that this compound has the potential to be developed into novel drugs to treat infections caused these microbes. 相似文献
83.
Paula Nilda Fergnani Adriana Ruggiero Soledad Ceccarelli Frédéric Menu Jorge Rabinovich 《Memórias do Instituto Oswaldo Cruz》2013,108(8):997-1008
We analysed the spatial variation in morphological diversity (MDiv) and species
richness (SR) for 91 species of Neotropical Triatominae to determine the ecological
relationships between SR and MDiv and to explore the roles that climate,
productivity, environmental heterogeneity and the presence of biomes and rivers may
play in the structuring of species assemblages. For each 110 km x 110 km-cell on a
grid map of America, we determined the number of species (SR) and estimated the mean
Gower index (MDiv) based on 12 morphological attributes. We performed bootstrapping
analyses of species assemblages to identify whether those assemblages were more
similar or dissimilar in their morphology than expected by chance. We applied a
multi-model selection procedure and spatial explicit analyses to account for the
association of diversity-environment relationships. MDiv and SR both showed a
latitudinal gradient, although each peaked at different locations and were thus not
strictly spatially congruent. SR decreased with temperature variability and MDiv
increased with mean temperature, suggesting a predominant role for ambient energy in
determining Triatominae diversity. Species that were more similar than expected by
chance co-occurred near the limits of the Triatominae distribution in association
with changes in environmental variables. Environmental filtering may underlie the
structuring of species assemblages near their distributional limits. 相似文献
84.
Douglas Eulálio Antunes Sergio Araujo Gabriela Porto Ferreira Ana Carolina Sousa Rodrigues da Cunha Adeilson Vieira da Costa Maria Aparecida Gon?alves Isabela Maria Bernardes Goulart 《Memórias do Instituto Oswaldo Cruz》2013,108(7):901-908
This cross-sectional retrospective study evaluated 440 leprosy patients; 57% (251/440) had leprosy reactions during and/or after multidrug therapy, 80.5% (202/251) of whom presented with multibacillary leprosy. At diagnosis, positive bacterial index (BI) [odds ratio (OR) = 6.39; 95% confidence interval (CI): 4.1-10.1)] or polymerase chain reaction (PCR) (OR = 9.15; 95% CI: 5.4-15.5) in skin smears, anti-phenolic glycolipid-1 (anti-PGL-1) ELISA (OR = 4.77; 95% CI: 2.9-7.9), leucocytosis (OR = 9.97; 95% CI: 3.9-25.7), thrombocytopenia (OR = 5.72; 95% CI: 2.3-14.0) and elevated lactate dehydrogenase (OR = 2.38; 95% CI: 1.4-4.0) were potential markers for the development of reactions during treatment. After treatment, positive BI (OR = 8.47; 95% CI: 4.7-15.3) and PCR (OR = 6.46; 95% CI: 3.4-12.3) in skin smears, anti-PGL-1 ELISA (OR = 2.25; 95% CI: 1.3-3.9), anaemia (OR = 2.36; 95% CI: 1.2-4.5), leucocytosis (OR = 4.14; 95% CI: 1.5-11.6) and thrombocytopenia (OR = 3.70; 95% CI: 1.3-2.2) were risk factors for the occurrence of reactions during the study period. The identification of groups with an increased risk for developing reactions will allow for the timely development of a treatment plan to prevent nerve damage and, therefore, the appearance of the disabling sequelae associated with the stigma of leprosy. 相似文献
85.
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87.
Gisela A. Samaja Olga Castro Lautaro D. Alvarez María V. Dansey Daiana S. Escudero Adriana S. Veleiro Adalí Pecci Gerardo Burton 《Bioorganic & medicinal chemistry letters》2013,23(10):2893-2896
27-Nor-Δ4-dafachronic acid was prepared in nine steps and 14% overall yield by two sequential 2-carbon homologations from 20β-carboxyaldehyde-4-pregnen-3-one. Its activity was evaluated in vivo, where it rescued the Mig phenotype of daf-9(rh50) Caenorhabditis elegans mutants and restored their normal resistance to oxidative stress. 27-Nor-Δ4-dafachronic acid was also able to directly bind and activate DAF-12 in a transactivation cell-based luciferase reporter assay, although it was less active than the corresponding 25R-and 25S dafachronic acids. The binding mode of the 27-Nor steroid was studied by molecular dynamics using a homology model of the CeDAF-12 receptor. 相似文献
88.
Graziano Di Giuseppe Michele Barbieri Adriana Vallesi Pierangelo Luporini Fernando Dini 《Molecular ecology》2013,22(15):4029-4037
Nuclear (18S and ITS) and mitochondrial (16S) ribosomal RNA gene sequences were determined from genetically distinct wild‐type strains of Antarctic (nine strains), Fuegian (four strains), Greenland (nine strains) and Svalbard (three strains) populations of the marine ciliate, Euplotes nobilii, and analysed for their nucleotide polymorphisms. A close genetic homogeneity was found within and between the Antarctic and Fuegian populations, while more significant levels of genetic differentiation were detected within and between the two Arctic populations, as well as between these populations and the Antarctic/Fuegian ones. The phylogeographical pattern that was derived from these data indicates that gene flow is not limited among Arctic populations; it equally connects the Arctic and Antarctic populations either directly, or through the Fuegian population. This indication reinforces previous evidence from laboratory assays of mating interactions between some of the strains analysed in this work that Southern and Northern polar populations of E. nobilii belong to a unique, panmictic population that substantially share the same gene pool. 相似文献
89.
Morphology and molecular phylogeny constitute the structural elements of diatom taxonomy. These approaches do not, however, give information on the functioning of taxa. Additional methods to serve a more integrated and wide-ranging taxonomy have therefore been called for. Metabolic fingerprinting is one approach used within the field of metabolomics, often applied in classification of samples. Here we apply metabolic fingerprinting in a taxonomic study of a cryptic diatom species. Strains of the cosmopolitan diatom Chaetoceros socialis from two geographical areas; the north-east Atlantic and Arctic and the Gulf of Naples, were cultivated at three different temperatures; 2.5, 8 and 13°C. The strains from the two different geographical areas exhibited different growth rates as well as different photosynthetic efficiencies. Algal extracts, collected at the end of the growth experiments, were analysed by Ultra-Performance Liquid Chromatography High Resolution Mass Spectrometry. The two groups of strains were separated by principal component analysis of their metabolic fingerprints. Analysis of the data revealed both qualitative and quantitative differences in metabolite markers. These phenotypic differences reinforce differences also found for morphology, phylogenetic markers and growth rates, and point at different adaptive characteristics in organisms living under different temperature regimes. 相似文献
90.
Adriana Fonseca Marques Daniel Esser Philip J. Rosenthal Matthias U. Kassack Luis Mauricio T.R. Lima 《Bioorganic & medicinal chemistry》2013,21(13):3667-3673
Falcipain-2 is a cysteine protease of the malaria parasite Plasmodium falciparum that plays a key role in the hydrolysis of hemoglobin, a process that is required by intraerythrocytic parasites to obtain amino acids. In this work we show that the polysulfonated napthylurea suramin is capable of binding to falcipain-2, inhibiting its catalytic activity at nanomolar concentrations against both synthetic substrates and the natural substrate hemoglobin. Kinetic measurements suggest that the inhibition occurs through an noncompetitive allosteric mechanism, eliciting substrate inhibition. Smaller suramin analogues and those with substituted methyl groups also showed inhibition within the nanomolar range. Our results identify the suramin family as a potential starting point for the design of falcipain-2 inhibitor antimalarials that act through a novel inhibition mechanism. 相似文献