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61.
62.
Ágnes Donkó Anna Orient Pál T. Szabó Gábor Németh Tibor Vántus György Kéri 《Free radical research》2013,47(5):440-445
The aim of this work was to study the dityrosine-forming activity of lactoperoxidase (LPO) and its potential application for measuring hydrogen peroxide (H2O2). It was observed that LPO was able to form dityrosine at low H2O2 concentrations. Since dityrosine concentration could be measured in a simple fluorimetric reaction, this activity of the enzyme was utilized for the measurement of H2O2 production in different systems. These experiments successfully measured the activity of NADPH oxidase 4 (Nox4) by this method. It was concluded that LPO-mediated dityrosine formation offers a simple way for H2O2 measurement. 相似文献
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64.
DANIEL M. GONZÁLEZ‐TOKMAN ISAAC GONZÁLEZ‐SANTOYO HUMBERTO LANZ‐MENDOZA ALEX CÓRDOBA AGUILAR 《Physiological Entomology》2010,35(4):364-372
Adaptive immunity allows vertebrates to gain protection against repeated pathogenic infections. Analogous responses (priming) have been recently uncovered in invertebrates. However, whether such responses are widespread is not known. The present study investigated the presence of immunological priming in males of a species whose phylogenetic position places it in one of the less derived insect orders. It is hypothesized that the efficiency of such a response could be related to animal condition, as assessed by the expression of a sexually selected ornament. Hetaerina americana Fabricius (Odonata: Calopterygidae) males bear a conspicuous ornament (a red wing spot), which is evolutionarily maintained via male territorial competition. Using field‐collected animals, a group of males is challenged with bacteria before exposure to a higher dose of the same or a different bacteria, and survival is compared with that of infected males not previously challenged, as well as control groups. Gram‐positive and Gram‐negative bacteria are used. To explore how long priming may take to work, the second exposure is carried out either after 1 or 5 days. Red spot and body size are entered in the analysis as predictors of survival within and between groups. There is no difference in survival among groups, which suggests no priming effect. Overall, red spot and body size are not consistent in explaining survival. 相似文献
65.
Willig Julia Biz Vianna Débora Renz Barreto Beckenkamp Aline Beckenkamp Liziane Raquel Sévigny Jean Wink Márcia Rosângela Buffon Andréia Pilger Diogo André 《Purinergic signalling》2020,16(1):29-40
Purinergic Signalling - Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm, characterized by the occurrence of the t(9;22)(q34;q11) translocation. First-line therapy for CML consists... 相似文献
66.
Ákos T. Kovács 《Environmental microbiology》2020,22(11):4524-4526
Assembly of microbial communities is shaped by various physical and chemical factors deriving from their environment, including other microbes inhabiting the certain niche. In addition to direct cell–cell contacts, primary and secondary metabolites impact the growth of microbial community members. Metabolites might act as growth-promoting (e.g., cross-feeding), growth-inhibiting (e.g., antimicrobials) or signalling molecules. In multi-species microbial assemblies, secreted metabolites might influence specific members of the community, altering species abundances and therefore the functioning of these microcosms. In the current issue, Cosetta and colleagues describe a unique volatile metabolite-mediated cross-kingdom interaction that shapes the cheese rind community assembly. The study paves the way of our understanding how fungus-produced volatile compounds promote the growth of a certain bacterial genus, a principal connection between community members of the cheese rind. 相似文献
67.
Rüdiger Ortiz-Álvarez Joan Cáliz Lluís Camarero Emilio O. Casamayor 《Environmental microbiology》2020,22(1):297-309
Microbial communities in natural ecosystems are subject to strong ecological rules. The study of local communities along a regional metacommunity can reveal patterns of community assembly, and disentangle the underlying ecological processes. In particular, we seek drivers of community assembly at the regional scale using a large lacustrine dataset (>300 lakes) along the geographical, limnological and physico-chemical gradients in the Pyrenees. By using high throughput amplicon sequencing of the 16S rRNA gene, and inferring environmental sources of bacterial immigrants, we showed that surface aquatic bacterial assemblages were strongly influenced by terrestrial populations from soil, biofilms or sediments, and primarily selected by a pH-alkalinity gradient. Indeed, source proportions explained 27% of the community variation, and chemistry 15% of the total variation, half of it shared with the sources. Major taxonomic groups such as Verrucomicrobia, Actinobacteria and Bacteroidetes showed higher aquatic affinities than Parcubacteria, Gammaproteobacteria, Alphaproteobacteria or Betaproteobacteria, which may be recruited and selected through different hydrographic habitats. A regional fingerprint was observed with lower alpha diversity and higher beta diversity in the central Pyrenees than in both ends. We suggest an ecological succession process, likely influenced by complex interactions of environmental source dispersal and environmental filtering along the mountain range geography. 相似文献
68.
Ángela Ares Margaret Mars Brisbin Kirk N. Sato Juan P. Martín Yoshiteru Iinuma Satoshi Mitarai 《Environmental microbiology》2020,22(11):4571-4588
Climate change scenarios predict tropical cyclones will increase in both frequency and intensity, which will escalate the amount of terrestrial run-off and mechanical disruption affecting coastal ecosystems. Bacteria are key contributors to ecosystem functioning, but relatively little is known about how they respond to extreme storm events, particularly in nearshore subtropical regions. In this study, we combine field observations and mesocosm experiments to assess bacterial community dynamics and changes in physicochemical properties during early- and late-season tropical cyclones affecting Okinawa, Japan. Storms caused large and fast influxes of freshwater and terrestrial sediment – locally known as red soil pollution – and caused moderate increases of macronutrients, especially SiO2 and PO43−, with up to 25 and 0.5 μM respectively. We detected shifts in relative abundances of marine and terrestrially derived bacteria, including putative coral and human pathogens, during storm events. Soil input alone did not substantially affect marine bacterial communities in mesocosms, indicating that other components of run-off or other storm effects likely exert a larger influence on bacterial communities. The storm effects were short-lived and bacterial communities quickly recovered following both storm events. The early- and late-season storms caused different physicochemical and bacterial community changes, demonstrating the context-dependency of extreme storm responses in a subtropical coastal ecosystem. 相似文献
69.
López-González Manuel Víctor González-García Marta Peinado-Aragonés Carlos Antonio Barbancho Miguel Ángel Díaz-Casares Amelia Dawid-Milner Marc Stefan 《Journal of physiology and biochemistry》2020,76(4):561-572
Journal of Physiology and Biochemistry - Connections between the midbrain dorsolateral periaqueductal grey (dlPAG) and the pontine A5 region have been shown. The stimulation of both regions evokes... 相似文献
70.
Monja-Mio Kelly M. Olvera-Casanova Diego Herrera-Herrera Gaston Herrera-Alamillo Miguel Ángel Sánchez-Teyer Felipe L. Robert Manuel L. 《In vitro cellular & developmental biology. Plant》2020,56(5):662-669
In Vitro Cellular & Developmental Biology - Plant - 相似文献