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41.
Lara Soares Aleixo de Carvalho Lívia Mara Silva Vinícius Carius de Souza Marcos Paulo Nascimento da Silva Priscila V. S. Z. Capriles Priscila de Faria Pinto Josué de Moraes Ademar Alves Da Silva Filho 《化学与生物多样性》2021,18(11):e2100604
Schistosomiasis, a neglected tropical disease caused by Schistosoma species, harms over 250 million people in several countries. The treatment is achieved with only one drug, praziquantel. Cardamonin, a natural chalcone with in vitro schistosomicidal activity, has not been in vivo evaluated against Schistosoma. In this work, we evaluated the in vivo schistosomicidal activities of cardamonin against Schistosoma mansoni worms and conducted enzymatic apyrase inhibition assay, as well as molecular docking analysis of cardamonin against potato apyrase, S. mansoni NTPDase 1 and S. mansoni NTPDase 2. In a mouse model of schistosomiasis, the oral treatment with cardamonin (400 mg/kg) showed efficacy against S. mansoni, decreasing the total worm load in 46.8 % and reducing in 54.5 % the number of eggs in mice. Cardamonin achieved a significant inhibition of the apyrase activity and the three-dimensional structure of the potato apyrase, obtained by homology modeling, showed that cardamonin may interact mainly through hydrogen bonds. Molecular docking studies corroborate with the action of cardamonin in binding and inhibiting both potato apyrase and S. mansoni NTPDases. 相似文献
42.
Daniel Silva Torres Bruna Alves de Oliveira Lígia Souza d Silveira Marcos Paulo da Silva Vinícius Rodrigues Durães Pereira Josué Moraes Mara Rúbia Costa Couri Rafaella Fortini Grenfell e Queiroz Patrícia Martins Parreiras Márcio Roberto Silva Lara Azevedo Alves Vinícius Carius de Souza Priscila Vanessa Zabala Capriles Goliatt Eveline Gomes Vasconcelos Ademar Alves da Silva Filho Priscila de Faria Pinto 《化学与生物多样性》2021,18(11):e2100439
In this work, two synthetic aurones revealed moderate schistosomicidal potential in in vitro and in vivo assays. Aurones ( 1 ) and ( 2 ) promoted changes in tegument integrity and motor activity, leading to death of adult Schistosoma mansoni worms in in vitro assays. When administered orally (two doses of 50 mg/kg) in experimentally infected animals, synthetic aurones ( 1 ) and ( 2 ) promoted reductions of 56.20 % and 57.61 % of the parasite load and stimulated the displacement towards the liver of the remaining adult worms. The oogram analysis revealed that the treatment with both aurones interferes with the egg development kinetics in the intestinal tissue. Seeking an action target for compounds ( 1 ) and ( 2 ), the connection with NTPDases enzymes, recognized as important therapeutic targets for S. mansoni, was evaluated. Molecular docking studies have shown promising results. The dataset reveals the anthelmintic character of these compounds, which can be used in the development of new therapies for schistosomiasis. 相似文献
43.
Agustín Maceda Jorge Reyes-Rivera Marcos Soto-Hernández Teresa Terrazas 《化学与生物多样性》2021,18(10):e2100431
Cactaceae family has heterogeneity in the accumulation of lignocellulose due to the diversity of shapes and anatomy of the wood. Most studies focus on fibrous and dimorphic species; but the non-fibrous species are poorly studied. The aims of this work were to analyze the syringyl/guaiacyl ratio of lignin and its distribution in secondary xylem, especially in non-fibrous species. The syringyl/guaiacyl (S/G) ratio was quantified from 34 species of cacti by nitrobenzene oxidation of free-extractive wood. The distribution of lignocellulose in wood sections stained with safranin O/fast green was determined with epifluorescence microscopy. The S/G ratio was heterogeneous; most of the non-fibrous species had a higher percentage of syringyl, while the fibrous ones accumulate guaiacyl. Fluorescence emission showed that vessel elements and wide-band tracheids had similar tonalities. It is hypothesized that the presence of a higher percentage of syringyl in most cacti is part of the defense mechanism against pathogens, which together with the succulence of the stem represent adaptations that contribute to survival in their hostile environments. 相似文献
44.
Andr Gomes-dos-Santos Manuel Lopes-Lima Andr M Machado Antnio Marcos Ramos Ana Usi Ivan N Bolotov Ilya V Vikhrev Sophie Breton L Filipe C Castro Rute R da Fonseca Juergen Geist Martin E
sterling Vincent Pri Amílcar Teixeira Han Ming Gan Oleg Simakov Elsa Froufe 《DNA research》2021,28(2)
Since historical times, the inherent human fascination with pearls turned the freshwater pearl mussel Margaritifera margaritifera (Linnaeus, 1758) into a highly valuable cultural and economic resource. Although pearl harvesting in M. margaritifera is nowadays residual, other human threats have aggravated the species conservation status, especially in Europe. This mussel presents a myriad of rare biological features, e.g. high longevity coupled with low senescence and Doubly Uniparental Inheritance of mitochondrial DNA, for which the underlying molecular mechanisms are poorly known. Here, the first draft genome assembly of M. margaritifera was produced using a combination of Illumina Paired-end and Mate-pair approaches. The genome assembly was 2.4 Gb long, possessing 105,185 scaffolds and a scaffold N50 length of 288,726 bp. The ab initio gene prediction allowed the identification of 35,119 protein-coding genes. This genome represents an essential resource for studying this species’ unique biological and evolutionary features and ultimately will help to develop new tools to promote its conservation. 相似文献
45.
Claudio Marcos Bedran Magalhães Renan Alves Resende Renata Noce Kirkwood 《Journal of electromyography and kinesiology》2013,23(5):1243-1249
The purpose of this study was to identify the gait strategies in women with mild and moderate knee osteoarthritis (OA). Forty women diagnosed with OA of the knee and 40 healthy women participated in the study. Toe-out progression angle, trunk lateral lean, hip internal abduction moment and gait speed were measured using Qualisys ProReflex System and two force plates. Principal component analysis was applied to extract features from the gait waveforms data that characterized the waveforms main modes of temporal variation. Discriminant analysis with a stepwise model was conducted to determine which strategies could best discriminate groups. According to the discriminant model, the PC2 of the internal abduction moment of the hip and the gait speed were the most discriminatory variables between the groups. The OA group showed decreased gait speed, decreased hip internal abduction moment during the loading response phase, and increased hip internal abduction moment during the mid and terminal stance phases. Interventions that may increase hip internal abduction moment, such as the strengthening of the hip abductors muscles, may benefit women with knee OA. Training slower than normal gait speeds must be considered in light of potential adverse implications on overall physical function, daily tasks, and safety. 相似文献
46.
47.
Albert Flexas Jaume Rosselló Julia F. Christensen Marcos Nadal Antonio Olivera La Rosa Enric Munar 《PloS one》2013,8(11)
We examined the influence of affective priming on the appreciation of abstract artworks using an evaluative priming task. Facial primes (showing happiness, disgust or no emotion) were presented under brief (Stimulus Onset Asynchrony, SOA = 20ms) and extended (SOA = 300ms) conditions. Differences in aesthetic liking for abstract paintings depending on the emotion expressed in the preceding primes provided a measure of the priming effect. The results showed that, for the extended SOA, artworks were liked more when preceded by happiness primes and less when preceded by disgust primes. Facial expressions of happiness, though not of disgust, exerted similar effects in the brief SOA condition. Subjective measures and a forced-choice task revealed no evidence of prime awareness in the suboptimal condition. Our results are congruent with findings showing that the affective transfer elicited by priming biases evaluative judgments, extending previous research to the domain of aesthetic appreciation. 相似文献
48.
49.
Dong Wook Han Natalia Tapia Marcos J. Araúzo-Bravo Kyung Tae Lim Kee Pyo Kim Kinarm Ko Hoon Taek Lee Hans R. Sch?ler 《PloS one》2013,8(6)
Epiblast stem cells (EpiSCs) and embryonic stem cells (ESCs) differ in their in vivo differentiation potential. While ESCs form teratomas and efficiently contribute to the development of chimeras, EpiSCs form teratomas but very rarely chimeras. In contrast to their differentiation potential, the reprogramming potential of EpiSCs has not yet been investigated. Here we demonstrate that the epiblast-derived pluripotent stem cells EpiSCs and P19 embryonal carcinoma cells (ECCs) exhibit a lower reprogramming potential than ESCs and F9 ECCs. In addition, we show that the low reprogramming ability is due to the lower levels of Sox2 in epiblast-derived stem cells. Consistent with this observation, overexpression of Sox2 enhances reprogramming efficiency. In summary, these findings suggest that a low reprogramming potential is a general feature of epiblast-derived stem cells and that the Sox2 level is a determinant of the cellular reprogramming potential. 相似文献
50.
Adriana S. Azevedo Ant?nio J. S. Gon?alves Marcia Archer Marcos S. Freire Ricardo Galler Ada M. B. Alves 《PloS one》2013,8(3)
The dengue envelope glycoprotein (E) is the major component of virion surface and its ectodomain is composed of domains I, II and III. This protein is the main target for the development of a dengue vaccine with induction of neutralizing antibodies. In the present work, we tested two different vaccination strategies, with combined immunizations in a prime/booster regimen or simultaneous inoculation with a DNA vaccine (pE1D2) and a chimeric yellow fever/dengue 2 virus (YF17D-D2). The pE1D2 DNA vaccine encodes the ectodomain of the envelope DENV2 protein fused to t-PA signal peptide, while the YF17D-D2 was constructed by replacing the prM and E genes from the 17D yellow fever vaccine virus by those from DENV2. Balb/c mice were inoculated with these two vaccines by different prime/booster or simultaneous immunization protocols and most of them induced a synergistic effect on the elicited immune response, mainly in neutralizing antibody production. Furthermore, combined immunization remarkably increased protection against a lethal dose of DENV2, when compared to each vaccine administered alone. Results also revealed that immunization with the DNA vaccine, regardless of the combination with the chimeric virus, induced a robust cell immune response, with production of IFN-γ by CD8+ T lymphocytes. 相似文献