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101.
Hüe S Monteiro RC Berrih-Aknin S Caillat-Zucman S 《Journal of immunology (Baltimore, Md. : 1950)》2003,171(4):1909-1917
The nonclassical MHC class I molecule MHC class I-related chain A (MICA) interacts with the NKG2D receptor expressed at the surface of most peripheral CD8 T cells, gammadelta T cells, and NK cells. We investigated the role of MICA-NKG2D interactions in the selection or maturation of the T cell repertoire within the thymus using MICA tetramers and anti-MICA mAbs. MICA tetramers identified a small population of late stage CD8 single-positive, CD45RA(+) CD62L(+) CCR7(+) CD69(-) thymocytes, a phenotype compatible with that of fully mature CD8(+) cells ready to emigrate to the periphery as naive cells. MICA molecules were expressed in the outer layer of Hassal's corpuscles within the medulla of normal thymus. In thymomas, an overexpression of MICA in cortical and medullar epithelial cells was observed. This was associated with a decreased percentage of NKG2D-positive thymocytes, which expressed a less mature phenotype than in normal thymus. These results indicate that CD8(+) thymocytes up-regulate NKG2D as they complete their developmental program before leaving the thymic medulla to seed the periphery, and identify NKG2D as a potential regulator of the developmental processes in T cells that are essential for immune homeostasis. 相似文献
102.
Rafaelle Fonseca de Matos Lúcia Carla Vasconcelos Mendonça Kaira Geiliane da Silva Souza Adriana Aparecida Durães Fonseca Elaine Mirla Souza Costa Marcus Vinicius Dias de Lima José Maria dos Santos Vieira Mioni Thielli Figueiredo Magalhães de Brito Marta Chagas Monteiro 《Folia microbiologica》2017,62(2):169-174
Certain non-steroidal anti-inflammatory drugs can inhibit fungal growth, fungal prostaglandin E2 production, and enzyme activation. This study aims to investigate the antifungal effect of nimesulide against pathogenic filamentous fungi and yeast. The experiments detailed below were also designed to investigate whether the action is dependent on E2 fungal prostaglandins. Our data showed that nimesulide exhibited potent antifungal activity, mainly against Trichophyton mentagrophytes (ATCC 9533) and Cryptococcus neoformans with MIC values of 2 and 62 μg/mL, respectively. This drug was also able to inhibit the growth of clinic isolates of filamentous fungi, such as Aspergillus fumigatus, and dermatophytes, such as T. rubrum, T. mentagrophytes, Epidermophyton floccosum, Microsporum canis, and M. gypseum, with MIC values ranging from 112 to 770 μg/mL. Our data also showed that the inhibition of fungal growth by nimesulide was mediated by a mechanism dependent on PGE2, which led to the inhibition of essential fungal enzymes. Thus, we concluded that nimesulide exerts a fungicidal effect against pathogenic filamentous fungi and yeast, involving the inhibition of fungal prostaglandins and fungal enzymes important to the fungal growth and colonization. 相似文献
103.
de Lourdes Corradi da Silva M Fukuda EK Vasconcelos AF Dekker RF Matias AC Monteiro NK Cardoso MS Barbosa AM Silveira JL Sassaki GL Carbonero ER 《Carbohydrate research》2008,343(4):793-798
Three D-glucans were isolated from the mycelium of the fungus Botryosphaeria rhodina MAMB-05 by sequential extraction with hot-water and hot aqueous KOH (2% w/v) followed by ethanol precipitation. Following their purification by gel permeation chromatography on Sepharose CL-4B, the structural characteristics of the D-glucans were determined by FT-IR and 13C NMR spectroscopy and, after methylation, by GC-MS. The hot-water extract produced a fraction designated Q1A that was a beta-(1-->6)-D-glucan with the following structure: [Formula: see text] The alkaline extract, when subjected to repeated freeze-thawing, yielded two fractions: K1P (insoluble) that comprised a beta-(1-->3)-D-glucan with beta-D-glucose branches at C-6 with the structure: [Formula: see text] and K1SA (soluble) consisting of a backbone chain of alpha-(1-->4)-linked D-glucopyranosyl residues substituted at O-6 with alpha-D-glucopyranosyl residues: [Formula: see text] 相似文献
104.
Wai Shing Tang Gabriel Monteiro da Silva Henry Kirveslahti Erin Skeens Bibo Feng Timothy Sudijono Kevin K. Yang Sayan Mukherjee Brenda Rubenstein Lorin Crawford 《PLoS computational biology》2022,18(5)
Identifying structural differences among proteins can be a non-trivial task. When contrasting ensembles of protein structures obtained from molecular dynamics simulations, biologically-relevant features can be easily overshadowed by spurious fluctuations. Here, we present SINATRA Pro, a computational pipeline designed to robustly identify topological differences between two sets of protein structures. Algorithmically, SINATRA Pro works by first taking in the 3D atomic coordinates for each protein snapshot and summarizing them according to their underlying topology. Statistically significant topological features are then projected back onto a user-selected representative protein structure, thus facilitating the visual identification of biophysical signatures of different protein ensembles. We assess the ability of SINATRA Pro to detect minute conformational changes in five independent protein systems of varying complexities. In all test cases, SINATRA Pro identifies known structural features that have been validated by previous experimental and computational studies, as well as novel features that are also likely to be biologically-relevant according to the literature. These results highlight SINATRA Pro as a promising method for facilitating the non-trivial task of pattern recognition in trajectories resulting from molecular dynamics simulations, with substantially increased resolution. 相似文献
105.
de Cássia Vieira Paião Jordana Monteiro Antonio Carlos do Nascimento Kronka Sérgio 《World journal of microbiology & biotechnology》2001,17(3):245-251
The susceptibility of the tick Boophilus microplus to Beauveria bassiana was evaluated by inoculating eggs, larvae and engorged females of the tick with five fungal isolates at concentrations of 106, 107 and 108 conidia/ml. Tick eggs (0.25 g) were immersed in 1 ml of a suspension of the different conidial concentrations for 1 min. Similar exposure was performed by immersion of 2000 larvae and homogeneous groups of nine engorged females in 2 and 20 ml of conidial suspension, respectively. Treated eggs, larvae and adults were placed in an incubator at 27 ± 1 °C and relative humidity above 80% for evaluation of the fungal action. All fungal isolates applied at all conidial concentrations reduced the hatching rate of larvae from treated eggs by 1.36–65.58% and increased the mortality rate of inoculated larvae by 0.8–70.49%. In the bioassay with engorged females, oviposition period was reduced by 9.69–47.80%, egg mass weight by 4.71–53.87%, estimated reproduction by 8.3–60.62%, egg production index by 5.03–54.20%, percent larval hatching by 0.27–13.96%, and the mortality rate of treated females was increased by 96.60–100%. The reduction of the estimated reproduction obtained for the treated groups ranged from 8.37 to 64.52%. The sporulation of the pathogen on dead females ranged from 3.70 to 88.88% depending on the isolate and concentration used. Isolates AM 09, CB 7 and JAB 07 were the most effective and effectiveness increased with increasing concentrations of conidia in the suspensions. 相似文献
106.
Aleksandro S. Da Silva Luziane P. Bellé Paula E.R. Bitencourt Herakles A. Garcia Perez Gustavo R. Thomé Marcio M. Costa Camila B. Oliveira Marta M.G. Teixeira Maria B. Moretto Cinthia M. Mazzanti Sonia T.A. Lopes Silvia G. Monteiro 《Experimental parasitology》2011,(1):173-177
The study was undertaken to evaluate changes in the activity of adenosine deaminase (ADA) in brains of rats infected by Trypanosoma evansi. Each rat was intraperitoneally infected with 106 trypomastigotes either suspended in fresh (group A; n = 13) and cryopreserved blood (group B; n = 13). Thirteen animals were used as control (group C). ADA activity was estimated in the cerebellum, cerebral cortex, striatum and hippocampus. No differences (P > 0.05) in ADA activity were observed in the cerebellum between infected and non-infected animals. Significant (P < 0.05) reductions in ADA activity occurred in cerebral cortex in acutely (day 4 post-infection; PI) and chronically (day 20 PI) infected rats. ADA activity was significantly (P < 0.05) decreased in the hippocampus in acutely infected rats, but significantly (P < 0.05) increased in the chronically infected rats. Significant (P < 0.05) reductions in ADA activity occurred in the striatum of chronically infected rats. Parasites could be found in peripheral blood and brain tissue through microscopic examination and PCR assay, respectively, in acutely and chronically infected rats. The reduction of ADA activity in the brain was associated with high levels of parasitemia and anemia in acute infections. Alterations in ADA activity of the brain in T. evansi-infected rats may have implications for pathogenesis of the disease. 相似文献
107.
Cristina M. Monteiro Susana C. Fonseca Paula M. L. Castro F. Xavier Malcata 《Journal of applied phycology》2011,23(1):97-103
Aquatic environments often contain toxic heavy metals that may enter the food web via uptake by microalgae and eventually
cause severe poisoning problems at higher trophic levels. The effects of Cd and Zn cations upon growth of two native green
microalgal species, Scenedesmus obliquus and Desmodesmus pleiomorphus (previously isolated from a polluted site in Northern Portugal), were accordingly evaluated. Growth inhibition of the microalgal
cells was determined following exposure for 96 h to several initial concentrations of aqueous solutions of either of those
two metals. At the higher end of Cd and Zn experimental concentration ranges, a significant reduction in cell density was
observed in the cultures; EC50 values, calculated after fitting a Weibull model to the experimental data, were 0.058 and 1.92 mg L−1 for Cd and 16.99 and 4.87 mg L−1 for Zn in the case of S. obliquus and D. pleiomorphus, respectively. One observed that S. obliquus can tolerate higher Zn concentrations than D. pleiomorphus, but the reverse holds regarding exposure to Cd. 相似文献
108.
Germinating seed ofDalbergia dolichopetala converted both [2H5]l-tryptophan and [2H5]indole-3-ethanol to [2H5]indole-3-acetic acid (IAA). Metabolism of [2-14C]IAA resulted in the production of indole-3-acetylaspartic acid (IAAsp), as well as several unidentified components, referred to as metabolites I, II, IV and V. Re-application of [14C]IAAsp to the germinating seed led to the accumulation of the polar, water-soluble compound, metabolite V, as the major metabolite, together with a small amount of IAA. Metabolites I, II and IV were not detected, nor were these compounds associated with the metabolism of [2-14C]IAA by shoots and excised cotyledons and roots from 26-d-oldD. dolichopetala seedlings. Both shoots and cotyledons converted IAA to IAAsp and metabolite V, while IAAsp was the only metabolite detected in extracts from excised roots. The available evidence indicates that inDalbergia, and other species, IAAsp may not act as a storage product that can be hydrolysed to provide the plant with a ready supply of IAA.Abbreviations HPLC-RC
high-performance liquid chromatography-radiocounting
- IAA
indole-3-acetic acid
- IAAsp
indole-3-acetylaspartic acid
- IAlnos
2-O-indole-3-acetyl-myo-inositol
- IEt
indole-3-ethanol 相似文献
109.
110.
Marina Gabriela Monteiro Carvalho Mori da Cunha Silvia Zia Fanny Oliveira Arcolino Marianne Sylvia Carlon Diego Vilibaldo Beckmann Ney Luis Pippi Dominguita Luhers Gra?a Elena Levtchenko Jan Deprest Jaan Toelen 《PloS one》2015,10(8)