Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Chronic Obstr Pulm Dis ; 11(3): 270-281, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38527191

RESUMO

Background: Daily physical activity is part of the self-management of patients with chronic obstructive pulmonary disease (COPD), and didactic information sessions may be insufficient for the provision of these skills. Prior activation can determine sensitivity to these sessions. We evaluated whether the activation in patients with COPD, as measured by the Patient Activation Measure (PAM)-13 questionnaire, determined their responses to an educational group session on physical activity (PA), which were measured with actigraphy by the number of steps/day. Methods: We conducted an uncontrolled clinical trial in an outpatient clinic with 75 patients with nonexacerbating COPD (forced expiratory volume in 1 second 30%-80%) who were selected consecutively. Patients were provided with an actigraph that they used for 15 days and completed the PAM-13 questionnaire. On the eighth day, they attended a group educational session where they were given PA information. We compared the changes in activity after the session by pooled PAM levels and the correlation between the change in the number of steps/day and the PAM-13 questionnaire. Results: A total of 26 patients had activation levels of 1-2, while 49 patients had levels of 3-4. After the session, patients in Levels 1-2 decreased their number of steps (-596±42), while those in Levels 3-4 increased them (680±253, p<0.01). The level of activation was positively correlated with change in the number of steps/day (p<0.05). Conclusion: COPD patients with greater activation showed greater improvements in daily PA after a group educational session.

3.
Dev Comp Immunol ; 138: 104523, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36055417

RESUMO

Silica crystals are potent activators of the inflammasome that cause a fibrotic lung disease, called silicosis, with no effective treatment available. We report here that injection of silica crystals into the hindbrain ventricle of zebrafish embryos led to the initiation of local and systemic immune responses driven through both Toll-like receptors (TLR)- and inflammasome-dependent signaling pathways, followed by induction of pro-fibrotic markers. Genetic and pharmacological analysis revealed that the Nlrp3 inflammasome regulated silica crystal-induced inflammation and pyroptotic cell death, but not emergency myelopoiesis. In addition, Cxcl8a/Cxcr2-dependent recruitment of myeloid cells to silica crystals was required to promote emergency myelopoiesis and systemic inflammation. The zebrafish model of silicosis developed here shed light onto the molecular mechanisms involved in the activation of the immune system by silica crystals.


Assuntos
Inflamassomos , Silicose , Animais , Imunidade , Inflamassomos/metabolismo , Inflamação , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Dióxido de Silício/efeitos adversos , Receptores Toll-Like/metabolismo , Peixe-Zebra/metabolismo
4.
Plants (Basel) ; 11(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35567247

RESUMO

Exposure to ultraviolet-B (UV-B) radiation can lead to oxidative damage in plants, increasing reactive oxygen species (ROS) production. To overcome ROS burst, plants have antioxidant mechanisms related to ROS scavenging which can be improved by elicitation with biological agents or derived molecules (elicitors), as they can trigger a physiological alert state called "priming". This work describes the effects of lipo-chitooligosaccharides (LCOs) treatment applied to tomato plants under UV-B stress. The LCOs used in the study are produced by three species of the genus Ensifer (formerly Sinorhizobium) (SinCEU-1, SinCEU-2, and SinCEU-3) were assayed on tomato plants under UV-B stress. LCOs were able to significantly increase most of the enzymatic activities related to ROS scavenging while non-enzymatic antioxidants were not modified. This response was associated with a lower oxidative stress, according to malondialdehyde (MDA) levels and the higher antioxidant capacity of the plants. Furthermore, the photosynthetic efficiency of LCOs-treated plants indicated a better physiological state than the control plants. Therefore, although more studies and deepening of certain aspects are necessary, LCOs have shown great potential to protect plants from high UV-B radiation conditions.

5.
Front Microbiol ; 12: 672751, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34489881

RESUMO

A novel Pseudomonas, designated strain BBB001T, an aerobic, rod-shaped bacterium, was isolated from the rhizosphere of Nicotiana glauca in Las Palmas Gran Canaria, Spain. Genomic analysis revealed that it could not be assigned to any known species of Pseudomonas, so the name Pseudomonas palmensis sp. nov. was proposed. A 16S rRNA gene phylogenetic analysis suggested affiliation to the Pseudomonas brassicae group, being P. brassicae MAFF212427 T the closest related type strain. Upon genomic comparisons of both strains, all values were below thresholds established for differentiation: average nucleotide identity (ANI, 88.29%), average amino acid identity (AAI, 84.53%), digital DNA-DNA hybridization (dDDH, 35.4%), and TETRA values (0.98). When comparing complete genomes, a total of 96 genes present exclusively in BBB001T were identified, 80 of which appear associated with specific subsystems. Phenotypic analysis has shown its ability to assimilate glucose, potassium gluconate, capric acid malate, trisodium citrate, and phenylacetic acid; it was oxidase positive. It is able to produce auxins and siderophores in vitro; its metabolic profile based on BIOLOG Eco has shown a high catabolic capacity. The major fatty acids accounting for 81.17% of the total fatty acids were as follows: C16:0 (33.29%), summed feature 3 (22.80%) comprising C16:1 ω7c and C16:1 ω6c, summed feature 8 (13.66%) comprising C18:1 ω7c, and C18:1ω6c and C17:0 cyclo (11.42%). The ability of this strain to improve plant fitness was tested on tomato and olive trees, demonstrating a great potential for agriculture as it is able to trigger herbaceous and woody species. First, it was able to improve iron nutrition and growth on iron-starved tomatoes, demonstrating its nutrient mobilization capacity; this effect is related to its unique genes related to iron metabolism. Second, it increased olive and oil yield up to 30% on intensive olive orchards under water-limiting conditions, demonstrating its capacity to improve adaptation to adverse conditions. Results from genomic analysis together with differences in phenotypic features and chemotaxonomic analysis support the proposal of strain BBB001T (=LMG 31775T = NCTC 14418T) as the type strain of a novel species for which the name P. palmensis sp. nov is proposed.

6.
J Sci Food Agric ; 101(1): 205-214, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32623714

RESUMO

BACKGROUND: The beneficial rhizobacterium, Pseudomonas fluorescens N 21.4, and its metabolic elicitors were inoculated in commercial cultivars of blackberry plants (Rubus cv. Loch Ness). Phenolic compounds present in red and black fruit and the expression of structural marker genes of the phenylpropanoid pathway during fruit ripening were studied. RESULTS: An inverse relationship between gene expression and accumulation of metabolites was seen, except for the RuDFR gene, which had a direct correlation with cyanidin 3-O-glucoside synthesis, increasing its content 1.3 times when RuDFR was overexpressed in the red fruit of plants inoculated with the metabolic elicitors of P. fluorescens N 21.4, compared with red fruit of plants inoculated with N 21.4. The RuCHS gene also had a fundamental role in the accumulation of metabolites. Both rhizobacterium and metabolic elicitors triggered the flavonoid metabolism, enhancing the catechin and epicatechin content between 1.1 and 1.6 times in the case of red fruit and between 1.1 and 1.8 times in the case of black fruit. Both treatments also boosted the anthocyanin, quercetin, and kaempferol derivative content, highlighting the effects of metabolic elicitors in red fruit and the effects of live rhizobacterium in black fruit. CONCLUSION: The metabolic elicitors' capacity to modulate gene expression and to increase secondary metabolites content was demonstrated. This work therefore suggests that they are effective, affordable, easily manageable, and ecofriendly plant inoculants that complement, or are alternatives to, beneficial rhizobacteria. © 2020 Society of Chemical Industry.


Assuntos
Flavonoides/química , Frutas/química , Frutas/metabolismo , Pseudomonas fluorescens/fisiologia , Rubus/microbiologia , Produção Agrícola , Flavonoides/metabolismo , Frutas/crescimento & desenvolvimento , Frutas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Rubus/química , Rubus/crescimento & desenvolvimento , Rubus/metabolismo , Metabolismo Secundário
7.
Plants (Basel) ; 9(8)2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32806693

RESUMO

In this work, the metabolic elicitors extracted from the beneficial rhizobacterium Pseudomonas fluorescens N 21.4 were sequentially fragmented by vacuum liquid chromatography to isolate, purify and identify the compounds responsible for the extraordinary capacities of this strain to induce systemic resistance and to elicit secondary defensive metabolism in diverse plant species. To check if the fractions sequentially obtained were able to increase the synthesis of isoflavones and if, therefore, they still maintained the eliciting capacity of the live strain, rapid and controlled experiments were done with soybean seeds. The optimal action concentration of the fractions was established and all of them elicited isoflavone secondary metabolism-the fractions that had been extracted with n-hexane being more effective. The purest fraction was the one with the highest eliciting capacity and was also tested in Arabidopsis thaliana seedlings to induce systemic resistance against the pathogen Pseudomonas syringae pv. tomato DC 3000. This fraction was then analyzed by UHPLC/ESI-QTOF-MS, and an alkaloid, two amino lipids, three arylalkylamines and a terpenoid were tentatively identified. These identified compounds could be part of commercial plant inoculants of biological and sustainable origin to be applied in crops, due to their potential to enhance the plant immune response and since many of them have putative antibiotic and/or antifungal potential.

8.
Front Plant Sci ; 8: 472, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28428793

RESUMO

Blackberries (Rubus spp.) are among the high added value food products relevant for human health due to the increasing evidence of the beneficial effects of polyphenols, which are very abundant in these fruits. Interestingly, these compounds also play a role on plant physiology, being especially relevant their role in plant defense against biotic and abiotic stress. Hence, we hypothesize that since blackberry fruits have high amounts of flavonols and anthocyanins, leaves would also have high amounts of these compounds, and can be studied as a source of active molecules; furthermore, leaf synthesis would support their high contents in fruits. To explore this hypothesis, the present study reports a de novo transcriptome analysis on field grown blackberry leaves and fruits at the same time point, to establish the metabolic relationship of these compounds in both organs. Transcripts were aligned against Fragaria vesca genome, and genes were identified and annotated in different databases; tissue expression pattern showed 20,463 genes common to leaves and fruits, while 6,604 genes were significantly overexpressed only in fruits, while another 6,599 genes were significantly overexpressed in leaves, among which flavonol-anthocyanin transporter genes were present. Bioactives characterization indicated that total phenolics in leaves were three-fold, and flavonols were six-fold than in fruits, while concentration of anthocyanins was higher in fruits; HPLC-MS analysis indicated different composition in leaves and fruits, with cyanidin-3-glucoside as the only common compound identified. Next, RT-qPCR of the core genes in the flavonol anthocyanin pathway and regulatory MYB genes were carried out. Interestingly, genes in the flavonol-anthocyanin pathway and flavonol-transport families were overexpressed in leaves, consistent with the higher bioactive levels. On the other hand, transcription factors were overexpressed in fruits anticipating an active anthocyanin biosynthesis upon ripening. This suggests that, in addition to the biosynthesis taking place in the fruits during ripening, translocation of flavonols from leaves to fruits contributes to the high amounts of bioactives starting to accumulate in fruits.

9.
Funct Plant Biol ; 44(11): 1063-1074, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32480633

RESUMO

The Pseudomonas fluorescens strain used in this work (Aur 6) has demonstrated its ability to improve fitness of different plant species upon biotic and abiotic stress conditions. Random mutants of this strain were constructed with the Tn5 transposon technology, and biological tests to evaluate loss of salt protection were conducted with all the mutants (104 mutants) on rice seedlings. Mutant 33 showed an evident reduction in its ability to protect plants upon salt stress challenge, whereas mutant 19 was more effective than the wild type. Enzymes related with oxidative stress were studied in both mutants and wild type. Enzyme activities were decreased with mutant 33 with regard to wild type, whereas mutant 19 did not produce important changes suggesting involvement of redox balance associated to the observed modifications in these antioxidant enzymes as one of the probable mechanisms used by these strains. Data of malondialdehyde (MDA) were consistent with this fact. Mutants also affected accumulation of proline, the most common osmolyte in plants. A second experiment to evaluate the ability of both mutants and wild type to stimulate growth on tomato plants was conducted, as this feature was previously demonstrated by wild type. Similar results were obtained in growth of both species, suggesting that mutations of both mutants are related with the capacities of the wild type to stimulate growth. To reveal mutated genes, both mutants were mapped. Three mutated genes were found in mutant 33. A gene related with a general secretion pathway protein D, a gene related with a putative two-component system sensor kinase (ColS), and a gene related with flagellar motor switch protein (FliG). In mutant 19, two mutated genes were found. One gene related with heavy metal efflux pump Czca family, and other gene of 16s rRNA.

10.
Curr Drug Saf ; 3(1): 35-45, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18690979

RESUMO

Inhaled corticosteroids (ICS) are the cornerstone of asthma management both in adults and in children. There are some adverse effects related to the use of these drugs in all ages. Those adverse effects can be local or systemic. From the paediatric point of view, the main worry relates to the effect on growth and on the integrity of the HPA-axis. At the recommended doses, their effect on the latter is not clinically relevant and the slight modification of cortisol levels which occurs while taking them reflects their presence in blood. Although there is a slowing down on growth velocity, this is reduced to the first months of treatment which are followed by a catch up: there is quite consistent data supporting their lack of significant effect on the final height. Other adverse effects which may appear in relation to ICS treatment in children, including infants, are mild or very sporadic. However, it is important to bear in mind that a small proportion of asthmatic children may have a certain idiosyncrasy which makes them especially sensitive to ICS. Furthermore, a close follow up is warranted when, due to the disease severity, higher than the recommended doses of ICS are administered.


Assuntos
Corticosteroides/efeitos adversos , Corticosteroides/uso terapêutico , Antiasmáticos/efeitos adversos , Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Administração por Inalação , Adolescente , Corticosteroides/administração & dosagem , Corticosteroides/farmacocinética , Envelhecimento/fisiologia , Antiasmáticos/administração & dosagem , Antiasmáticos/farmacocinética , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Humanos , Lactente
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...