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161.
Mourão LC Morais CG Bueno LL Jimenez MC Soares IS Fontes CJ Guimarães Lacerda MV Xavier MS Barnwell JW Galinski MR Braga EM 《Microbes and infection / Institut Pasteur》2012,14(9):730-739
An important step when designing a vaccine is identifying the antigens that function as targets of naturally acquired antibodies. We investigated specific antibody responses against two Plasmodium vivax vaccine candidates, PvMSP-119 and PvMSP-3α359?798. Moreover, we assessed the relationship between these antibodies and morbidity parameters. PvMSP-119 was the most immunogenic antigen and the frequency of responders to this protein tended to increase in P. vivax patients with higher parasitemia. For both antigens, IgG antibody responses tended to be lower in patients who had experienced their first bout of malaria. Furthermore, anemic patients presented higher IgG antibody responses to PvMSP-3α359?798. Since the humoral response involves a number of antibodies acting simultaneously on different targets, we performed a Principal Component Analysis (PCA). Anemic patients had, on average, higher first principal component scores (IgG1/IgG2/IgG3/IgG4 anti-MSP3α), which were negatively correlated with hemoglobin levels. Since antibodies against PfMSP-3 have been strongly associated with clinical protection, we cannot exclude the possibility of a dual role of PvMSP-3 specific antibodies in both immunity and pathogenesis of vivax malaria. Our results confirm the high immunogenicity of the conserved C terminus of PvMSP-1 and points to the considerable immunogenicity of polymorphic PvMSP-3α359?798 during natural infection. 相似文献
162.
Viviane Castelo Branco Reis André Moraes Nicola Osmar de Souza Oliveira Neto Vinícius Daniel Ferreira Batista Lidia Maria Pepe de Moraes Fernando Araripe Gon?alves Torres 《Journal of industrial microbiology & biotechnology》2012,39(11):1673-1683
Used for millennia to produce beverages and food, Saccharomyces cerevisiae also became a workhorse in the production of biofuels, most notably bioethanol. Yeast strains have acquired distinct characteristics that are the result of evolutionary adaptation to the stresses of industrial ethanol production. JP1 is a dominant industrial S. cerevisiae strain isolated from a sugarcane mill and is becoming increasingly popular for bioethanol production in Brazil. In this work, we carried out the genetic characterization of this strain and developed a set of tools to permit its genetic manipulation. Using flow cytometry, mating type, and sporulation analysis, we verified that JP1 is diploid and homothallic. Vectors with dominant selective markers for G418, hygromycin B, zeocin, and ρ-fluoro-dl-phenylalanine were used to successfully transform JP1 cells. Also, an auxotrophic ura3 mutant strain of JP1 was created by gene disruption using integration cassettes with dominant markers flanked by loxP sites. Marker excision was accomplished by the Cre/loxP system. The resulting auxotrophic strain was successfully transformed with an episomal vector that allowed green fluorescent protein expression. 相似文献
163.
Vinícius Silva Junqueira Leonardo de Azevedo Peixoto Bruno Galvêas Laviola Leonardo Lopes Bhering Simone Mendon?a Tania da Silveira Agostini Costa Rosemar Antoniassi 《PloS one》2016,11(6)
The biggest challenge for jatropha breeding is to identify superior genotypes that present high seed yield and seed oil content with reduced toxicity levels. Therefore, the objective of this study was to estimate genetic parameters for three important traits (weight of 100 seed, oil seed content, and phorbol ester concentration), and to select superior genotypes to be used as progenitors in jatropha breeding. Additionally, the genotypic values and the genetic parameters estimated under the Bayesian multi-trait approach were used to evaluate different selection indices scenarios of 179 half-sib families. Three different scenarios and economic weights were considered. It was possible to simultaneously reduce toxicity and increase seed oil content and weight of 100 seed by using index selection based on genotypic value estimated by the Bayesian multi-trait approach. Indeed, we identified two families that present these characteristics by evaluating genetic diversity using the Ward clustering method, which suggested nine homogenous clusters. Future researches must integrate the Bayesian multi-trait methods with realized relationship matrix, aiming to build accurate selection indices models. 相似文献
164.
Aleš Imramovský Jarmila Vinšová Juana Monreal Férriz Vladimír Buchta Josef Jampílek 《Bioorganic & medicinal chemistry letters》2009,19(2):348-351
A series of novel, highly antimicrobial salicylanilide esters of N-protected amino acids were synthesized and characterized. Their in vitro antimicrobial activity against eight fungal strains and Mycobacterium tuberculosis was determined. The compounds had the highest level of activity against Aspergillus fumigatus, Absidia corymbifera and Trichophyton mentagrophytes, and these levels were higher than that of the standard drug fluconazole. In addition, three compounds showed interesting antituberculosis activity, with inhibition ranging from 89% to 99%. (S)-4-Chloro-2-(4-trifluoromethylphenylcarbamoyl)-phenyl 2-benzyloxy-carbonylamino-propionate had the highest level of both antifungal and antimycobacterial activity. The structure–activity relationships of the new compounds are discussed. 相似文献
165.
Gabriela Julianelly Sartori Livia Deris Prado Helvécio Vinícius Antunes Rocha 《AAPS PharmSciTech》2017,18(8):3011-3020
Efavirenz is a fundamental drug in the HIV therapy; however, it has a low bioavailability due to low water solubility. Particle nanonization should enhance its dissolution and therefore its bioavailability. Nanocrystallization is a promising technique for preparing drug nanocrystals. A solution containing efavirenz (EFV) and methanol was added to an aqueous solution of particle stabilizers, under sonication. The adequate polymer stabilizer and its concentration and drug load were evaluated. Particle size and zeta potential of suspensions were measured. Nanosuspensions were freeze-dried and the resulting powder was characterized by some techniques, with special attention to dissolution. Particle size and zeta potential analysis showed that HMPC and PVP were the most suitable polymers. All samples prepared with these stabilizers had nanosized particles and proper zeta potential; however, sedimentation and particle growth were detected with Turbiscan?. Time-related destabilization occurred when the lowest polymer concentration of 20% was used. SEM analysis of the dried powder shows film formation for suspensions with 40% of polymer and particle aggregation in samples with less polymer. Dissolution profiles of samples were higher than EFV raw material, although the lower the polymer concentration, the higher the dissolution. 相似文献
166.
Désio Aurélio Farias-de-Oliveira Vinícius Cotta-de-Almeida Déa Maria S. Villa-Verde Ingo Riederer Juliana de Meis Wilson Savino 《Memórias do Instituto Oswaldo Cruz》2013,108(7):825-831
Developing thymocytes interact with thymic epithelial cells (TECs) through cell-cell
interactions, TEC-derived secretory moieties and extracellular matrix (ECM)-mediated
interactions. These physiological interactions are crucial for normal thymocyte
differentiation, but can be disrupted in pathological situations. Indeed, there is severe
thymic atrophy in animals acutely infected with Trypanosoma cruzi due to
CD4+CD8+ thymocyte depletion secondary to caspase-mediated apoptosis, together with
changes in ECM deposition and thymocyte migration. We studied an in vitro model of TEC
infection by T. cruzi and found that infected TEC cultures show a reduced
number of cells, which was likely associated with decreased proliferative capacity, but
not with increased cell death, as demonstrated by bromodeoxyuridine and annexin-V
labelling. The infected TEC cultures exhibited increased expression of fibronectin (FN),
laminin (LM) and type IV collagen. Importantly, treatment with FN increased the relative
number of infected cells, whereas treatment with anti-FN or anti-LM antibodies resulted in
lower infection rates. Consistent with these data, we observed increased thymocyte
adhesion to infected TEC cultures. Overall, these results suggest that ECM molecules,
particularly FN, facilitate infection of the thymic epithelium and that the consequent
enhancement of ECM expression might be associated with changes in TEC-thymocyte
interactions. 相似文献
167.
beta-Galactosidase (beta-Gal) activity is a widely accepted biomarker to detect senescence both in situ and in vitro. A cytochemical assay based on production of a blue-dyed precipitate that results from the cleavage of the chromogenic substrate X-Gal is commonly used. Blue and nonblue cells are counted under the microscope and a semiquantitative percentage of senescent cells can be obtained. Here, we present a quantitative, fast, and easy to use chemiluminescent assay to detect senescence. The Galacton chemiluminescent method used to detect the prokaryotic beta-Gal reporter enzyme in transfection studies was adapted to assay mammalian beta-Gal. The assay showed linear production of luminescence in a time- and cell-number-dependent manner. The chemiluminescent assay showed significant correlation with the cytochemical assay in detecting replicative senescence (Pearson r=0.8486, p<0.005). Moreover, the chemiluminescent method (Galacton) also detected stress-induced senescence in cells treated with H2O2 similar to the cytochemical assay (X-Gal) (Galacton: control 25,207.3+/-6548.6, H2O2 52,487.4+/-16,284.9, p<0.05; X-Gal: control 41.31+/-7.0%, H2O2 92.97+/-2.8%, p<0.01). Thus, our method is well suited to the detection of replicative and stress-induced senescence in cell culture. 相似文献
168.
169.
Misuse of bird digital distribution maps creates reversed spatial diversity patterns in the Amazon 下载免费PDF全文
Mariana M. Vale Tamires L. Marques Mario Cohn‐Haft Marcus Vinícius Vieira 《Biotropica》2017,49(5):636-642
It is well known that bird richness in the Amazon is greater in upland forests and that seasonally flooded forest is particularly species poor. However, the misleading pattern of greater bird richness in seasonally flooded forest has emerged seemingly unnoticed numerous times in richness maps in the literature. We hypothesize that commission errors in digital distribution maps (DDMs) are the cause behind the misleading richness pattern. In the Amazon, commission errors are a consequence of the different methodological treatment given to large‐ranged versus small‐ranged habitat specialists when mapping distributions. DDMs of 1007 Amazonian birds were examined, and maps that had commission errors were corrected. We generated two richness maps, one from the overlay of original DDMs and another from the overlay of the corrected ones. We identified 291 species whose distribution maps had errors. In the original data, seasonally flooded forests showed higher species richness than upland forest, but this pattern was reverted in the corrected richness map. Commission errors were 35 times more likely in the seasonally flooded forest. We conclude that DDMs accurately portray the distribution of single species in the Amazon. Commission errors in individual maps, however, accumulate when they are overlaid, explaining the misleading pattern for birds in the Amazon. DDMs can continue to be used mapping richness, as long as, at a regional scale: (1) basic map refinements are carried, or (2) only small‐range species are used for mapping species richness. 相似文献
170.
Mesenchymal stem cells improves survival in LPS‐induced acute lung injury acting through inhibition of NETs formation 下载免费PDF全文
Leonardo Pedrazza Aline Andrea Cunha Carolina Luft Nailê Karine Nunes Felipe Schimitz Rodrigo Benedetti Gassen Ricardo Vaz Breda Marcio Vinícius Fagundes Donadio Angela Terezinha de Souza Wyse Paulo Marcio Condessa Pitrez Jose Luis Rosa Jarbas Rodrigues de Oliveira 《Journal of cellular physiology》2017,232(12):3552-3564