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41.
The Non‐Canonical Substrates of Trypanosoma cruzi Tyrosine and Aspartate Aminotransferases: Branched‐Chain Amino Acids
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Nubia Carolina Manchola Ariel Mariano Silber Cristina Nowicki 《The Journal of eukaryotic microbiology》2018,65(1):70-76
Trypanosoma cruzi, the etiological agent of Chagas disease, lacks genes that encode canonical branched‐chain aminotransferases. However, early studies showed that when epimastigotes were grown in the presence of 14C1‐DL‐leucine, the label was incorporated into various intermediates. More recently, our studies provided evidence that T. cruzi epimastigotes display a single ATP‐dependent and saturable transport system that enables epimastigotes to uptake branched‐chain amino acids (BCAAs) from the culture media. To extend our knowledge of the first step of BCAA catabolism, the ability of this parasite's noncanonical broad specificity aminotransferases, such as tyrosine aminotransferase (TAT) and aspartate aminotransferase (ASAT), to transaminate these amino acids was investigated. Indeed, our results show that TAT and ASAT utilize BCAAs as substrates; however, both enzymes differ in their catalytic competence in utilizing these amino donors. For instance, ASAT transaminates isoleucine nearly 10‐fold more efficiently than does TAT. This unique characteristic of TAT and ASAT allows to explain how BCAAs can be oxidized in the absence of a BCAA transaminase in T. cruzi. 相似文献
42.
W. Seyffert 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1963,33(8):356-365
Ohne ZusammenfassungMit 3 Abbildungen 相似文献
43.
Michael Seyffert Pooja Lagisetty Jessica Landgraf Vineet Chopra Paul N. Pfeiffer Marisa L. Conte Mary A. M. Rogers 《PloS one》2016,11(2)
Background
Insomnia is of major public health importance. While cognitive behavioral therapy is beneficial, in-person treatment is often unavailable. We assessed the effectiveness of internet-delivered cognitive behavioral therapy for insomnia.Objectives
The primary objectives were to determine whether online cognitive behavioral therapy for insomnia could improve sleep efficiency and reduce the severity of insomnia in adults. Secondary outcomes included sleep quality, total sleep time, time in bed, sleep onset latency, wake time after sleep onset, and number of nocturnal awakenings.Data Sources
We searched PubMed/MEDLINE, the Cumulative Index to Nursing and Allied Health Literature, PsycInfo, Cochrane Library, Embase, and the Web of Science for randomized trials.Methods
Studies were eligible if they were randomized controlled trials in adults that reported application of cognitive behavioral therapy for insomnia via internet delivery. Mean differences in improvement in sleep measures were calculated using the Hartung-Knapp-Sidik-Jonkman method for random effects meta-analysis.Results
We found 15 trials, all utilizing a pretest-posttest randomized control group design. Sleep efficiency was 72% at baseline and improved by 7.2% (95% CI: 5.1%, 9.3%; p<0.001) with internet-delivered cognitive behavioral therapy versus control. Internet-delivered cognitive behavioral therapy resulted in a decrease in the insomnia severity index by 4.3 points (95% CI: -7.1, -1.5; p = 0.017) compared to control. Total sleep time averaged 5.7 hours at baseline and increased by 20 minutes with internet-delivered therapy versus control (95% CI: 9, 31; p = 0.004). The severity of depression decreased by 2.3 points (95% CI: -2.9, -1.7; p = 0.013) in individuals who received internet-delivered cognitive behavioral therapy compared to control. Improvements in sleep efficiency, the insomnia severity index and depression scores with internet-delivered cognitive behavioral therapy were maintained from 4 to 48 weeks after post-treatment assessment. There were no statistically significant differences between sleep efficiency, total sleep time, and insomnia severity index for internet-delivered versus in-person therapy with a trained therapist.Conclusion
In conclusion, internet-delivered cognitive behavioral therapy is effective in improving sleep in adults with insomnia. Efforts should be made to educate the public and expand access to this therapy. Registration Number, Prospero: CRD42015017622 相似文献44.
Photoluminescence shift in frustules of two pennate diatoms and nanostructural changes to their pores
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Nubia V. Arteaga‐Larios Yuri Nahmad Hugo R. Navarro‐Contreras Armando Encinas J. Viridiana García‐Meza 《Luminescence》2014,29(8):969-976
The diatom silicified cell wall (frustule) contains pore arrays at the micro‐ to nanometer scale that display efficient luminescence within the visible spectrum. Morphometric analysis of the size and arrangement of pores was conducted to observe whether any correlation exists with the photoluminescence (PL) of two diatom species of different ages. UV‐excited PL displays four clearly defined peaks within the blue‐region spectrum, on top of the broad PL characteristic of synthetic porous silicon dioxide, recorded for reference and where discrete lines are absent. A set of shifted emission lines was observed when diatom cultures reached adulthood. These discrete line shifts correlate with structural changes observed in adult frustules: reduction in pore diameter; appearance of pores within pores, 10 nm in size; an increase in the gap distance between stria; and the deposition of several girdle bands with a concomitant increase in the diatom waist length, as well as the appearance of pores on such bands. Destruction of the pores results in the disappearance of all discrete emission lines. The PL shifts are correlated with a substantial increment of Si–OH groups adsorbed on the frustule surface, as revealed by Fourier transform infrared spectroscopy. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
45.
Cristian Antonio Rojas Nubia Barbosa Eloy Marcelo de Freitas Lima Roberta Lopes Rodrigues Luciana Ozório Franco Kristiina Himanen Gerrit T. S. Beemster Adriana Silva Hemerly Paulo Cavalcanti Gomes Ferreira 《Plant molecular biology》2009,71(3):307-318
The Anaphase Promoting Complex (APC) controls CDK activity by targeting the ubiquitin-dependent proteolysis of S-phase and
mitosis-promoting cyclins. Here, we report that the ectopic expression of the Arabidopsis CDC27a, an APC subunit, accelerates plant growth and results in plants with increased biomass production. CDC27a overexpression
was associated to apical meristem restructuration, protoplasts with higher 3H-thimidine incorporation and altered cell-cycle marker expression. Total protein extracts immunoprecipitated with a CDC27a
antibody showed ubiquitin ligase activity, indicating that the Arabidopsis CDC27a gets incorporated into APC complexes. These results indicate a role of AtCDC27a in regulation of plant growth and
raise the possibility that the activity of the APC and the rates of plant cell division could be regulated by the concentration
of the CDC27a subunit.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Cristian Antonio Rojas and Nubia Barbosa Eloy contributed equally to this work. 相似文献
46.
Moncada L Carrasquilla MC Spinelli G Lotta I Matta N 《Memórias do Instituto Oswaldo Cruz》2010,105(8):978-980
A new species of Culicoides of the subgenus Diphaomyia Vargas from high altitudes of the Andes in Colombia is described and photographied. The species is compared with its similar congener Culicoides marinkellei Wirth & Lee. Data on the collecting site and notes on the species daily activity are also provided. 相似文献
47.
48.
Giehl Nubia França da Silva Cabette Helena Soares Ramos Dias-Silva Karina Juen Leandro Moreira Felipe Ferraz Figueiredo de Castro Lourivaldo Amâncio Ferreira Victor Rennan Santos Batista Joana Darc 《Hydrobiologia》2020,847(16):3497-3510
Hydrobiologia - Veredas environments play a critical role on the perennialization of streams in the Cerrado Biome, but alterations to their physiognomies are becoming increasingly more common,... 相似文献
49.
Wanderson M. Silva Núbia Seyffert Alessandra Ciprandi Agenor V. Santos Thiago L. P. Castro Luis G. C. Pacheco Debmalya Barh Yves Le Loir Adriano M. C. Pimenta Anderson Miyoshi Artur Silva Vasco Azevedo 《Current microbiology》2013,67(4):460-465
Corynebacterium pseudotuberculosis is the etiologic agent of caseous lymphadenitis a chronic infectious disease affecting small ruminants. The 2D-DIGE technique was used to compare the exoproteomes of two C. pseudotuberculosis biovar ovis strains isolated from goat (strain 1002) and sheep (strain C231). Seventeen proteins differentially produced were identified here. Nine proteins appeared over-produced in the exoproteome of 1002 goat strain and 8 in that of C231 sheep strain. These proteins were related to various biological functions, such as the cell envelope, respiratory metabolism and proteolysis. This proteomic analysis revealed strain-specific exoproteins although each of the corresponding genes was found in both strain genomes. Such differential expression pattern may reflect inter-strain differences in adaptation to a specific host, in pathogenicity and or in antigenicity of this pathogenic bacterium. 相似文献
50.
Eloy NB de Freitas Lima M Van Damme D Vanhaeren H Gonzalez N De Milde L Hemerly AS Beemster GT Inzé D Ferreira PC 《The Plant journal : for cell and molecular biology》2011,68(2):351-363
The largest E3 ubiquitin-ligase complex, known as anaphase-promoting complex/cyclosome (APC/C), regulates the proteolysis of cell cycle regulators such as CYCLIN B and SECURIN that are essential for sister-chromatid separation and exit from mitosis. Despite its importance, the role of APC/C in plant cells and the regulation of its activity during cell division remain poorly understood. Here, the Arabidopsis thaliana APC/C subunit APC10 was characterized and shown to functionally complement an apc10 yeast mutant. The APC10 protein was located in specific nuclear bodies, most probably resulting from its association with the proteasome complex. An apc10 Arabidopsis knockout mutant strongly impaired female gametogenesis. Surprisingly, constitutive overexpression of APC10 enhanced leaf size. Through kinematic analysis, the increased leaf size was found to be due to enhanced rates of cell division during the early stages of leaf development and, at the molecular level, by increased APC/C activity as measured by an amplification of the proteolysis rate of the mitotic cyclin, CYCB1;1. 相似文献