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871.
Viviana Márquez-Velásquez Rosseval Galdino Leite Andres Hernandez-Serna Fredy Alvarado 《Journal of fish biology》2021,98(1):333-336
Analysis of feeding habits was performed for early life stages of Brachyplatystoma rousseauxii and Brachyplatystoma filamentosum in the Madeira River, Brazil. Stomach contents of B. rousseauxii and B. filamentosum were identified and analysed to provide the percentage of frequency of occurrence (%FO) and area (%A) and the alimentary index (IAi). The order Diptera represented the most important item consumed by both species. This is the first analyses of the trophic ecology of these ecologically and economically important species of the Amazonian region in early life stages. 相似文献
872.
Schneider Naira Fernanda Zanchett Menegaz Danusa Dagostin Andre Luiz Andreotti Persich Lara Rocha Sayonarah C. Ramos Ana Carolina Pacheco Cortes Vanessa Faria Fontes Carlos Frederico Leite de Pádua Rodrigo Maia Munkert Jennifer Kreis Wolfgang Braga Fernão Castro Barbosa Leandro A. Silva Fátima Regina Mena Barreto Simões Cláudia Maria Oliveira 《Molecular and cellular biochemistry》2021,476(4):1825-1848
Molecular and Cellular Biochemistry - Cardiac glycosides (CGs) are useful drugs to treat cardiac illnesses and have potent cytotoxic and anticancer effects in cultured cells and animal models.... 相似文献
873.
Silva Daniela Fernanda Dezotti de Oliveira Fujii Lucas Chiarotto Gabriela Bortolança de Oliveira Camila Andrea de Andrade Thiago Antônio Moretti de Oliveira Alexandre Leite Rodrigues Esquisatto Marcelo Augusto Marretto Mendonça Fernanda Aparecida Sampaio dos Santos Gláucia Maria Tech de Aro Andrea Aparecida 《Molecular biology reports》2021,48(2):1233-1241
Molecular Biology Reports - The literature has shown the beneficial effects of microcurrent (MC) therapy on tissue repair. We investigated if the application of MC at... 相似文献
874.
Fernanda Araújo Batista Leite Rosângela Luci Brandão Renata Santiago de Oliveira Buzatti José Pires de Lemos-Filho Maria Bernadete Lovato 《Tree Genetics & Genomes》2014,10(2):307-316
Assessing the population genetic structure of threatened species is important for developing successful conservation strategies. In this study, we evaluated the fine-scale spatial genetic structure (SGS) of Dalbergia nigra from a regenerating secondary forest fragment and compared it with previous data from a primary forest of a large reserve. A total of 107 adult and 111 saplings were mapped and genotyped for seven microsatellite loci. The genetic diversity was high and similar in adults (H e?=?0.682) and saplings (H e?=?0.680). The spatial extent of SGS was higher in adults than in saplings. Overlapping generations in the potentially reproductive individuals is the likely explanation for the higher SGS in adults (Sp?=?0.016) in relation to the saplings (Sp?=?0.010). The SGS in the adults from the secondary forest fragment was similar to that found in the primary forest. Considering the SGS found in adults, from both the secondary and primary forests, seeds for ex situ conservation should be collected from trees at least 80 m apart to reduce the genetic similarity between samples. These results highlight the importance of preserving small forest fragments to allow successful regeneration and maintenance of the genetic diversity in D. nigra. 相似文献
875.
Edney Geraldo da Silveira Firmiano Adriano C. Rabelo Cleocir J. Dalmaschio Antonio N. Pinheiro Ernesto C. Pereira Wido H. Schreiner Edson Robeto Leite 《Liver Transplantation》2014,4(6)
Layered molybdenum disulfide (MoS2) is deposited by microwave heating on a reduced graphene oxide (RGO). Three concentrations of MoS2 are loaded on RGO, and the structure and morphology are characterized. The first layers of MoS2 are detected as being directly bonded with the oxygen of the RGO by covalent chemical bonds (Mo‐O‐C). Electrochemical characterizations indicate that this electroactive material can be cycled reversibly between 0.25 and 0.8 V in 1 m HClO4 solution for hybrids with low concentrations of MoS2 layers (LCMoS2/RGO) and between 0.25 and 0.65 V for medium (MCMoS2/RGO) and high concentrations (HCMoS2/RGO) of MoS2 layers on graphene. The specific capacitance measured values at 10 mV s?1 are 128, 265, and 148 Fg?1 for the MoS2/RGO with low, medium, and high concentrations of MoS2, respectively, and the calculated energy density is 63 W h kg?1 for the LCMoS2/RGO hybrid. This supercapacitor electrode also exhibits superior cyclic stability with 92% of the specific capacitance retained after 1000 cycles. 相似文献
876.
877.
Antonio B. Oliveira Jr. Francisco M. Fatore Fernando V. Paulovich Osvaldo N. Oliveira Jr. Vitor B. P. Leite 《PloS one》2014,9(7)
Protein folding occurs in a very high dimensional phase space with an exponentially large number of states, and according to the energy landscape theory it exhibits a topology resembling a funnel. In this statistical approach, the folding mechanism is unveiled by describing the local minima in an effective one-dimensional representation. Other approaches based on potential energy landscapes address the hierarchical structure of local energy minima through disconnectivity graphs. In this paper, we introduce a metric to describe the distance between any two conformations, which also allows us to go beyond the one-dimensional representation and visualize the folding funnel in 2D and 3D. In this way it is possible to assess the folding process in detail, e.g., by identifying the connectivity between conformations and establishing the paths to reach the native state, in addition to regions where trapping may occur. Unlike the disconnectivity maps method, which is based on the kinetic connections between states, our methodology is based on structural similarities inferred from the new metric. The method was developed in a 27-mer protein lattice model, folded into a 3×3×3 cube. Five sequences were studied and distinct funnels were generated in an analysis restricted to conformations from the transition-state to the native configuration. Consistent with the expected results from the energy landscape theory, folding routes can be visualized to probe different regions of the phase space, as well as determine the difficulty in folding of the distinct sequences. Changes in the landscape due to mutations were visualized, with the comparison between wild and mutated local minima in a single map, which serves to identify different trapping regions. The extension of this approach to more realistic models and its use in combination with other approaches are discussed. 相似文献
878.
Natália Bueno Leite Dayane dos Santos Alvares Bibiana Monson de Souza Mário Sérgio Palma João Ruggiero Neto 《European biophysics journal : EBJ》2014,43(4-5):121-130
Polybia-MP1 (IDWKKLLDAAKQIL-NH2), a helical peptide extracted from the venom of a Brazilian wasp, has broad-spectrum antimicrobial activities without being hemolytic or cytotoxic. This peptide has also displayed anticancer activity against cancer cell cultures. Despite its high selectivity, MP1 has an unusual low net charge (Q = +2). The aspartic residue (D2) in the N-terminal region plays an important role in its affinity and selectivity; its substitution by asparagine (D2N mutant) led to a less selective peptide. Aiming to explore the importance of this residue for the peptides’ affinity, we compared the zwitterionic and anionic vesicle adsorption activity of Polybia-MP1 versus its D2N mutant and also mastoparan X (MPX). The adsorption, electrostatic, and conformational free energies were assessed by circular dichroism (CD) and fluorescence titrations using large unilamellar vesicles (LUVs) at the same conditions in association with measurement of the zeta potential of LUVs in the presence of the peptides. The adsorption free energies of the peptides, determined from the partition coefficients, indicated higher affinity of MP1 to anionic vesicles compared with the D2N mutant and MPX. The electrostatic and conformational free energies of MP1 in anionic vesicles are less favorable than those found for the D2N mutant and MPX. Therefore, the highest affinity of MP1 to anionic vesicles is likely due to other energetic contributions. The presence of D2 in MP1 makes these energetic components 1.2 and 1.5 kcal/mol more favorable compared with the D2N mutant and MPX, respectively. 相似文献
879.
Ednildes de Almeida Olympio Rua Marcella Leite Porto Jean Pierre Louzada Ramos Breno Valentim Nogueira Silvana dos Santos Meyrelles Elisardo Corral Vasquez Thiago de Melo Costa Pereira 《Journal of biomedical science》2014,21(1)
Background
Although cigarette smoke is known to be a complex mixture of over 4000 substances that can lead to damage through active or passive smoking, its mechanisms and biochemical consequences in pregnancy and neonates are not yet fully understood. Therefore, in the present study, we propose to study the impact of smoking during gestation on the viability of blood mononuclear cells (MNC) from umbilical cords of newborns to assess the degree of oxidative stress and cell viability. After childbirth, the cord blood and the umbilical cord were immediately collected in public hospitals in Greater Vitoria, ES, Brazil. Flow cytometry was used to analyze the cord blood followed by biochemical and histological tests to analyze possible changes in the umbilical cord.Results
Pregnant smokers had a reduction of MNC viability from the umbilical cord (10%), an increase in the production of reactive oxygen species (ROS) and an increase in cell apoptosis (~2-fold) compared to pregnant non-smokers. In the umbilical cord, it was observed an increase of advanced oxidation protein products - AOPP (~2.5-fold) and a loss of the typical architecture and disposition of endothelial cells from the umbilical artery.Conclusions
These data suggest that maternal cigarette smoking during pregnancy (even in small amounts) may compromise the viability of MNC cells and damage the umbilical cord structure, possibly by excessive ROS bioavailability. 相似文献880.
Deborah Mattos Guimarães Apgaua Rubens Manoel dos Santos Diego Gualberto Sales Pereira Gisele Cristina de Oliveira Menino Gabriela Gomes Pires Marco Aurélio Leite Fontes David Yue Phin Tng 《Biodiversity and Conservation》2014,23(1):217-232
Tropical biomes are species rich, but some biomes such as seasonally dry tropical forests (SDTFs) are still inadequately studied compared to their co-occurring rain forest and savanna. SDTFs occur in areas of high environmental heterogeneity, resulting in high beta (β)-diversity or species turnover, but this has so far only been accessed using a single β-diversity measure, and at a spatial scale that is of limited applicability for reserve planning. The Caatinga Biogeographic Domain in Brazil contains the largest known extent of SDTF which are poorly studied and inadequately reserved. We therefore studied the variation in species richness and species turnover among SDTF between localities and between known floristic communities. From six localities within the Caatinga Biogeographic Domain we recorded all tree species with a circumference at breast height equaling or exceeding 10 cm within 106 400 m2 survey plots. From the species presence/absence data we calculated three measures of β-diversity between pairs of study localities and between different floristic communities representing: (i) species similarity, (ii) differences between species richness, and (iii) species gain and loss. Our results confirm the high β-diversity of SDTFs and species turnover between localities and also between floristic communities. The three indices were also complementary to each other and can be used to maximize accuracy in β-diversity studies. The implications of our study for conservation and reserve planning of SDTFs are discussed. 相似文献