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1.
Planta ; 255(4): 77, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35239061

RESUMO

MAIN CONCLUSION: Ceratodon purpureus showed changes in disaccharides, flavonoids, and carotenoids throughout annual seasons. These changes indicate harsher environmental conditions during the dry period, directing metabolic precursors to enhance the antioxidant system. Bryophytes are a group of land plants comprising mosses (Bryophyta), liverworts (Marchantyophyta), and hornworts (Antocerotophyta). This study uses the molecular networking approach to investigate the influence of seasonality (dry and rainy seasons) on the metabolome and redox status of the moss Ceratodon purpureus (Hedw.) Brid., from Campos do Jordão, Brazil. Samples of C. purpureus were submitted to three extraction methods: 80% methanol producing the soluble fraction (intracellular compounds), followed by debris hydrolysis using sodium hydroxide producing the insoluble fraction (cell wall conjugated compounds), both analyzed by HPLC-MS; and extraction using pre-cooled methanol, separated into polar and non-polar fractions, being both analyzed by GC-MS. All fractions were processed using the Global Natural Product Social Molecular Network (GNPS). The redox status was assessed by the analysis of four enzyme activities combined with the analysis of the contents of ascorbate, glutathione, carotenoids, reactive oxygen species (ROS), and malondialdehyde acid (MDA). During the dry period, there was an increase of most biflavonoids, as well as phospholipids, disaccharides, long-chain fatty acids, carotenoids, antioxidant enzymes, ROS, and MDA. Results indicate that C. purpureus is under harsher environmental conditions during the dry period, mainly due to low temperature and less water availability (low rainfall).


Assuntos
Biflavonoides , Briófitas , Bryopsida , Antioxidantes/metabolismo , Biflavonoides/metabolismo , Bryopsida/metabolismo , Metaboloma
2.
J Exp Bot ; 72(3): 941-958, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33165620

RESUMO

Nitric oxide (NO) has been implicated as part of the ripening regulatory network in fleshy fruits. However, very little is known about the simultaneous action of NO on the network of regulatory events and metabolic reactions behind ripening-related changes in fruit color, taste, aroma and nutritional value. Here, we performed an in-depth characterization of the concomitant changes in tomato (Solanum lycopersicum) fruit transcriptome and metabolome associated with the delayed-ripening phenotype caused by NO supplementation at the pre-climacteric stage. Approximately one-third of the fruit transcriptome was altered in response to NO, including a multilevel down-regulation of ripening regulatory genes, which in turn restricted the production and tissue sensitivity to ethylene. NO also repressed hydrogen peroxide-scavenging enzymes, intensifying nitro-oxidative stress and S-nitrosation and nitration events throughout ripening. Carotenoid, tocopherol, flavonoid and ascorbate biosynthesis were differentially affected by NO, resulting in overaccumulation of ascorbate (25%) and flavonoids (60%), and impaired lycopene production. In contrast, the biosynthesis of compounds related to tomato taste (sugars, organic acids, amino acids) and aroma (volatiles) was slightly affected by NO. Our findings indicate that NO triggers extensive transcriptional and metabolic rewiring at the early ripening stage, modifying tomato antioxidant composition with minimal impact on fruit taste and aroma.


Assuntos
Frutas/fisiologia , Óxido Nítrico/fisiologia , Solanum lycopersicum/fisiologia , Etilenos , Regulação da Expressão Gênica de Plantas , Fenótipo
3.
Plant Biotechnol J ; 18(10): 2027-2041, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32068963

RESUMO

Photoreceptor engineering has recently emerged as a means for improving agronomically beneficial traits in crop species. Despite the central role played by the red/far-red photoreceptor phytochromes (PHYs) in controlling fruit physiology, the applicability of PHY engineering for increasing fleshy fruit nutritional content remains poorly exploited. In this study, we demonstrated that the fruit-specific overexpression of a constitutively active GAF domain Tyr252 -to-His PHYB2 mutant version (PHYB2Y252H ) significantly enhances the accumulation of multiple health-promoting antioxidants in tomato fruits, without negative collateral consequences on vegetative development. Compared with the native PHYB2 overexpression, PHYB2Y252H -overexpressing lines exhibited more extensive increments in transcript abundance of genes associated with fruit plastid development, chlorophyll biosynthesis and metabolic pathways responsible for the accumulation of antioxidant compounds. Accordingly, PHYB2Y252H -overexpressing fruits developed more chloroplasts containing voluminous grana at the green stage and overaccumulated carotenoids, tocopherols, flavonoids and ascorbate in ripe fruits compared with both wild-type and PHYB2-overexpressing lines. The impacts of PHYB2 or PHYB2Y252H overexpression on fruit primary metabolism were limited to a slight promotion in lipid biosynthesis and reduction in sugar accumulation. Altogether, these findings indicate that mutation-based adjustments in PHY properties represent a valuable photobiotechnological tool for tomato biofortification, highlighting the potential of photoreceptor engineering for improving quality traits in fleshy fruits.

4.
Molecules ; 25(20)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066182

RESUMO

Floral colour change is a widespread phenomenon in angiosperms, but poorly understood from the genetic and chemical point of view. This article investigates this phenomenon in Pleroma raddianum, a Brazilian endemic species whose flowers change from white to purple. To this end, flavonoid compounds and their biosynthetic gene expression were profiled. By using accurate techniques (Ultra Performance Liquid Chromatography-High-Resolution Mass Spectrometry (UPLC-HRMS)), thirty phenolic compounds were quantified. Five key genes of the flavonoid biosynthetic pathway were partially cloned, sequenced, and the mRNA levels were analysed (RT-qPCR) during flower development. Primary metabolism was also investigated by gas chromatography coupled to mass spectrometry (GC-EIMS), where carbohydrates and organic acids were identified. Collectively, the obtained results suggest that the flower colour change in P. raddianum is determined by petunidin and malvidin whose accumulation coincides with the transcriptional upregulation of early and late biosynthetic genes of the flavonoid pathway, mainly CHS and ANS, respectively. An alteration in sugars, organic acids and phenolic co-pigments is observed together with the colour change. Additionally, an increment in the content of Fe3+ ions in the petals, from the pink to purple stage, seemed to influence the saturation of the colour.


Assuntos
Flores/química , Flores/fisiologia , Melastomataceae/fisiologia , Pigmentação/fisiologia , Antocianinas/genética , Antocianinas/metabolismo , Brasil , Cromatografia Líquida de Alta Pressão , Flavonoides/genética , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas , Espectrometria de Massas , Melastomataceae/química , Metais/análise , Pigmentos Biológicos/análise , Pigmentos Biológicos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
Molecules ; 25(12)2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32604974

RESUMO

Environmental conditions influence specialized plant metabolism. However, many studies aiming to understand these modulations have been conducted with model plants and/or under controlled conditions, thus not reflecting the complex interaction between plants and environment. To fully grasp these interactions, we investigated the specialized metabolism and genetic diversity of a native plant in its natural environment. We chose Myrcia bella due to its medicinal interest and occurrence in Brazilian savanna regions with diverse climate and soil conditions. An LC-HRMS-based metabolomics approach was applied to analyze 271 samples harvested across seven regions during the dry and rainy season. Genetic diversity was assessed in a subset of 40 samples using amplified fragment length polymorphism. Meteorological factors including rainfall, temperature, radiation, humidity, and soil nutrient and mineral composition were recorded in each region and correlated with chemical variation through multivariate analysis (MVDA). Marker compounds were selected using a statistically informed molecular network and annotated by dereplication against an in silico database of natural products. The integrated results evidenced different chemotypes, with variation in flavonoid and tannin content mainly linked to soil conditions. Different levels of genetic diversity and distance of populations were found to be correlated with the identified chemotypes. These observations and the proposed analytical workflow contribute to the global understanding of the impact of abiotic factors and genotype on the accumulation of given metabolites and, therefore, could be valuable to guide further medicinal exploration of native species.


Assuntos
Flavonoides/química , Metabolômica/métodos , Myrtaceae/química , Taninos/química , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Cromatografia Líquida , DNA de Plantas/genética , Variação Genética , Pradaria , Myrtaceae/genética , Extratos Vegetais/química
6.
Molecules ; 24(4)2019 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-30781526

RESUMO

Tibouchina pulchra (Cham.) Cogn. is a plant native to Brazil whose genus and family (Melastomataceae) are poorly studied with regards to its metabolite profile. Phenolic pigments of pink flowers were studied by ultra-performance liquid chromatography with a photodiode array detector and electrospray ionization quadrupole time-of-flight mass spectrometry. Therein, twenty-three flavonoids were identified with eight flavonols isolated by preparative high-performance liquid chromatography and analysed by one- and two-dimensional nuclear magnetic resonance. Kaempferol derivatives were the main flavonols, encompassing almost half of the detected compounds with different substitution patterns, such as glucoside, pentosides, galloyl-glucoside, p-coumaroyl-glucoside, and glucuronide. Concerning the anthocyanins, petunidin p-coumaroyl-hexoside acetylpentoside and malvidin p-coumaroyl-hexoside acetylpentoside were identified and agreed with previous reports on acylated anthocyanins from Melastomataceae. A new kaempferol glucoside was identified as kaempferol-(2''-O-methyl)-4'-O-α-d-glucopyranoside. Moreover, twelve compounds were described for the first time in the genus with five being new to the family, contributing to the chemical characterisation of these taxa.


Assuntos
Flavonoides/química , Flores/química , Glicosídeos/química , Melastomataceae/química , Pigmentação , Árvores , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
7.
Appl Nurs Res ; 39: 211-216, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29422161

RESUMO

PURPOSE: To identify the expectations and perceptions of clients concerning the quality of hospital care provided to them and their respective companions at a private Brazilian hospital using SERVQUAL. The SERVQUAL questionnaire can provide information concerning expectations and perceptions of clients. In addition, it is able to identify the participation of frontline employees and how they contribute to the organization's end product (service delivery). METHODS: In total, 172 inpatients for surgical reasons answered the SERVQUAL questionnaire. It consists of 23 pairs of statements, 22 of which are distributed into the dimensions of tangibles, reliability, responsiveness, assurance and empathy. Statement 23 refers to the overall quality of care. Exploratory analysis, internal consistency (Cronbach's alpha) and the kappa Coefficient were calculated using the Statistical Package for Social Sciences and SAS 9.2. Ethical approval was obtained from the Institutional Review Board at the Hospital das Clínicas at the University of São Paulo at Ribeirao Preto Medical School. RESULTS: Most participants had a bachelor's degree and were over than 60years old. Cronbach's alpha coefficients indicated good internal consistency (α=0.93) and high levels of agreement were observed (91.10%). CONCLUSION: The SERVQUAL questionnaire was sensitive to items in each dimension for which clients' perceptions surpassed their expectations. IMPLICATIONS FOR NURSING MANAGEMENT: The continuous quality assessment of health services is mandatory for nursing leadership. The nursing leadership can further explore the SERVQUAL with a view to better attending to the clients' expectations.


Assuntos
Hospitais/estatística & dados numéricos , Hospitais/normas , Satisfação do Paciente/estatística & dados numéricos , Garantia da Qualidade dos Cuidados de Saúde/estatística & dados numéricos , Garantia da Qualidade dos Cuidados de Saúde/normas , Qualidade da Assistência à Saúde/estatística & dados numéricos , Qualidade da Assistência à Saúde/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Inquéritos e Questionários
8.
Chem Biodivers ; 13(8): 990-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27286480

RESUMO

Annona crassiflora Mart. is a native tree from Brazilian savanna. Isoquinoline alkaloids are characteristic of species of Annonaceae. This work aimed to assess the magnitude of genetic diversity among different populations of A. crassiflora using AFLP markers, and verify the existence of any correlation between the AFLP data and previous reported alkaloid composition. A. crassiflora from eight populations in the states of São Paulo, Goiás, Minas Gerais, and Distrito Federal were analyzed. The data suggest a low, moderate, and high level of genetic diversity from different populations of A. crassiflora. Concentration of alkaloids was significantly correlated with AFLP data, suggesting interaction between chemical and molecular markers in A. crassiflora. The data of association between the chemical and genetic differentiation of A. crassiflora may be useful to establish cultivation areas allowing the definition of strategies to preserve their genetic diversity with an interest in specific chemotypes for genetic improvement programs focused on sustainable utilization of this specie.


Assuntos
Annona/química , Annona/genética , Isoquinolinas/análise , Brasil
9.
Mol Omics ; 20(3): 203-212, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38289293

RESUMO

Plants should be probably thought of as the most formidable chemical laboratory that can be exploited for the production of an incredible number of molecules with remarkable structural and chemical diversity that cannot be matched by any synthetic libraries of small molecules. The bryophytes chemistry has been neglected for too long, but in the last ten years, this scenery is changing, with several studies being made using extracts from bryophytes, aimed at the characterization of interesting metabolites, with their metabolome screened. The main objective of this study was to analyze the metabolome of Brittonodoxa subpinnata, a native Brazilian moss species, which occurs in the two Brazilian hotspots. GC-MS and LC-MS2 were performed. All extracts were analyzed using the molecular networking approach. The four extracts of B. subpinnata (polar, non-polar, soluble, and insoluble) resulted in 928 features detected within the established parameters. 189 (20.4%) compounds were annotated, with sugars, fatty acids, flavonoids, and biflavonoids as the major constituents. Sucrose was the sugar with the highest quantity; palmitic acid the major fatty acid but with great presence of very long-chain fatty acids rarely found in higher plants, glycosylated flavonoids were the major flavonoids, and biflavonoids majorly composed by units of flavones and flavanones, exclusively found in the cell wall. Despite the high percentage, this work leaves a significant gap for future works using other structure elucidation techniques, such as NMR.


Assuntos
Biflavonoides , Brasil , Flavonoides/química , Cromatografia Gasosa-Espectrometria de Massas , Açúcares , Ácidos Graxos
11.
Kidney Int Rep ; 9(4): 1047-1056, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38765576

RESUMO

Introduction: This retrospective study on patients with biopsy-proven lupus nephritis (LN) aimed to assess the probability of sustained clinical remission (sCR) and to investigate sCR effects on disease flares and impaired kidney function (IKF). Methods: sCR was defined as clinical-Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) = 0 and estimated glomerular filtration rate (eGFR) >60 ml/min per 1.73 m2 lasting ≥1 year; IKF: eGFR <60 ml/min per 1.73 m2 for >3 months. We analyzed the probability of achieving and maintaining sCR, and the yearly risk of flare. Cox models were used to identify predictors of sCR and IKF with variables analyzed as time-dependent covariates when appropriate. Results: Of 303 patients followed-up with for 14.8 (interquartile range: 9.8-22) years, 257 (84.8%) achieved sCR. The probability of achieving sCR progressively increased over time reaching 90% at 15 years. Baseline age (hazard ratio [HR]: 1.017; 95% confidence interval [CI]: 0.005-1.029; P = 0.004), hydroxychloroquine intake (HR: 1.385; 95% CI: 1.051-1.825; P = 0.021), and absence of arterial hypertension (HR: 0.699; 95% CI: 0.532-0.921; P = 0.011) were independent predictors of sCR. Among patients who achieved sCR, 142 (55.3%) developed a lupus flare after a median time of 3.6 (2.3-5.9) years. In the remaining 115 patients, sCR persisted for 9.5 (5.8-14.5) years. The probability of sCR to persist at 15 years was 38%. SLE flare risk decreased to 10%, 5%, and 2% in patients with sCR lasting <5, 5 to 10, and >10 years, respectively. At the last observation, 57 patients (18.81%) had IKF. sCR achievement (HR: 0.18, P < 0.001) and its duration (HR: 0.83, P < 0.001) were protective against IKF. Conclusion: sCR is an achievable target in LN management and protects against IKF. The longer the sCR, the higher the chance of its persistence and the lower the risk of SLE flares.

12.
Stat Med ; 31(29): 4114-34, 2012 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-22829461

RESUMO

In the city of Casale Monferrato, the largest Italian factory that produced asbestos-cement goods was active from 1907 to 1985. Consequently, asbestos fibers scattered in the surrounding area and caused an enormous number of cases of pleural mesothelioma. Owing to the very long latency of this disease, many subjects have not exhibited its symptoms yet. The aim of this paper is to model and predict the future evolution of the number of deaths due to this disease among residents in the area around that city. The model used here is based on a cellular automata that is assumed to pass through three steps: exposure, contamination, and diagnosis. In this way, forecasts of the future evolution take into account the environmental conditions that changed over the last century because of different levels of plant activity. The model is fitted to annual diagnosis data from 1954 to 2008. Results show that deaths will not end until 2031 and that in the next two decades, at least 505 more subjects will be diagnosed with this disease.


Assuntos
Amianto/toxicidade , Exposição Ambiental , Previsões , Mesotelioma/mortalidade , Modelos Estatísticos , Neoplasias Pleurais/mortalidade , Feminino , Humanos , Itália/epidemiologia , Masculino
13.
Anal Bioanal Chem ; 399(4): 1715-23, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21153584

RESUMO

In the present study, a method based on liquid chromatography with diode array detection (HPLC-DAD) coupled to an electrospray ionisation (ESI) interface was developed for the determination of the constituents in the aqueous preparations of Viola odorata L. flowering tops. The developed assay was fast, simple and effective and permitted the quality control of the preparations. The aim of this work was to assess the qualitative and quantitative profile of the investigated preparations, which find until today wide applications in food and cosmetic industry, and to propose a validated method for their quality control. Characteristic constituents of V. odorata flowers are considered to be the anthocyanins; however, a detailed literature research showed that data concerning their chemical content are scarce. HPLC-DAD-ESI-MS analyses supported by extensive preparative chromatographic investigations and 2D NMR analyses revealed the predominance of complex flavonol glycosides and permitted the complete characterisation of the content of V. odorata preparations. This is the first report of detailed analysis of the chemical composition of V. odorata flowers.


Assuntos
Flores/química , Viola/química , Cromatografia Líquida de Alta Pressão , Controle de Qualidade , Espectrometria de Massas por Ionização por Electrospray , Água/química
14.
Plant Sci ; 311: 110994, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34482907

RESUMO

Drought is a pivotal cause for crop yield reductions. When subjected to recurrent external stimuli, plants can develop memory of stress responses that, eventually, enables improved plant tolerance to environmental changes. In addition, despite causal relationships, these responses may vary according to hierarchical levels of observation. Thus, this study aims to check the responses of recurrent and non-recurrent stresses in two rice genotypes observing their drought memory responses at different levels of organization, that is, on a physiological, biochemical and metabolomic scale and for end in global PCA. For this, seventy variables were measured on the scales described in order to obtain a large number of observations. The memory responses were evident in almost all scales observed. The lowland genotype, especially plants not subjected to recurrent water shortage, showed higher damage to the photosynthetic apparatus under drought conditions, although it has exhibited more evident memory response effect after rehydration. On the other hand, the upland genotype appears to be more tolerant to drought insofar lower biochemical damage was observed. Specific behaviors of each genotype at biochemical and metabolomics levels and similar behavior at physiological level were observed. This study demonstrates the importance of observation at different hierarchical levels.


Assuntos
Adaptação Fisiológica/genética , Desidratação/genética , Desidratação/fisiopatologia , Secas , Oryza/genética , Oryza/fisiologia , Água/metabolismo , Brasil , Produtos Agrícolas/genética , Produtos Agrícolas/fisiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo , Estresse Fisiológico/genética
15.
Sci Total Environ ; 769: 145080, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33736256

RESUMO

Eugenia uniflora L. is an important fruit tree native to tropical South America that adapts to different habitats, thanks to its metabolic diversity and ability to adjust the leaf antioxidant metabolism. We hypothesized that this metabolic diversity would also enable E. uniflora to avoid oxidative damage and tolerate the enhanced ozone (O3) concentrations that have been registered in the (sub)tropics. We investigated whether carbohydrates, polyphenols and antioxidants are altered and markers of oxidative damage (ROS accumulation, alterations in leaf gas exchange, growth and biomass production) are detected in plants exposed to two levels of O3 (ambient air and twice elevated ozone level in a O3-FACE system for 75 days). Phytotoxic O3 dose above a threshold of 0 nmol m-2 s-1 (POD0) and accumulated exposure above 40 ppb (AOT40) were 3.6 mmol m-2 and 14.898 ppb h at ambient, and 4.7 mmol m-2 and 43.881 ppb h at elevated O3. Twenty-seven primary metabolites and 16 phenolic compounds were detected in the leaves. Contrary to the proposed hypothesis that tropical broadleaf trees are relatively O3 tolerant, we concluded that E. uniflora plants are sensitive to elevated O3 concentrations. Experimental POD0 values were lower than the critical levels for visible foliar O3, because of low stomatal conductance. In spite of this low stomatal O3 uptake, we found classic O3 injury, e.g. reduction in carbohydrates and fatty acids concentrations; non-significant changes in the polyphenol profile; inefficient antioxidant responses; increased contents of ROS and indicators of lipid peroxidation; reductions in stomatal conductance, net photosynthesis, root/shoot ratio and height growth. However, we also found some compensation mechanisms, e.g. increased leaf concentration of polyols for protecting the membranes, and increased leaf number for compensating the decline of photosynthetic rate. These results help filling the knowledge gap about tropical tree responses to O3.


Assuntos
Poluentes Atmosféricos , Eugenia , Ozônio , Poluentes Atmosféricos/análise , Ozônio/análise , Fotossíntese , Folhas de Planta/química , América do Sul , Árvores
16.
Photochem Photobiol ; 97(1): 166-179, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32762087

RESUMO

Combined enhanced UV-B radiation and drought may induce different morphological and physiological alterations in plants than either abiotic stress alone. We evaluated morphology, biomass, and primary and secondary metabolism changes in seedlings of two common bean cultivars, IAC Imperador (drought-resistant) and IAC Milênio. To test the hypothesis that cultivars responded differently to combined stresses in a controlled environment, seedlings of the examined been cultivars were exposed to UV-B and/or drought treatments for three weeks. The cultivars behaved differently, especially to the drought treatment, suggesting that they use different mechanisms to cope with unfavorable environmental conditions. IAC Imperador showed a stronger protective response, modifying wax composition and primary metabolism, and improving its resistance to UV-B radiation. For IAC Imperador, the accumulation of cuticular wax and alkane was higher under combined stress but production of primary alcohols was reduced, suggesting a possible fatty acyl switch. Root/shoot length and biomass ratios increased in both cultivars, particularly for the combined stress, indicating a common plant response. We show that these two bean cultivars responded more strongly to UV-B and combined stress than drought alone as evident in changes to their chemistry and biology. This shows the importance of investigating plant morphological and physiological responses to combined stress.


Assuntos
Phaseolus/fisiologia , Estresse Fisiológico , Raios Ultravioleta , Água , Phaseolus/classificação , Folhas de Planta/fisiologia , Plântula
17.
Plant Physiol Biochem ; 136: 222-229, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30703634

RESUMO

The present study aimed to investigate the reciprocal effects of Phoradendron perrottetii (mistletoe) and T. guianensis (host plant) regarding their polyphenol composition. Taking into account that tannins are important molecules in plant defense and their biosynthesis tends to be enhanced when a species is exposed to stress, we address the following questions: (1) Are the tannins found in our model species important in the interaction between host and mistletoe? (2) Does the presence of mistletoe induce changes in the content of tannins and other polyphenols in the host plant? (3) Do we find differences between the tannin sub-groups in the responses of the host plant to mistletoe? (4) Could the observed differences reflect the relative importance of one tannin group over another as chemical defense against the mistletoe? Using a polyphenol and tannin group-specific MRM methods we quantified four different tannin sub-groups together with flavonoid and quinic acid derivatives by ultra-performance liquid chromatography tandem mass spectrometry together with the oxidative and protein precipitation activities of leaves and branches of Tapirira guianensis and Phoradendron perrottetii. We selected leaves and branches of six non-parasitized trees of T. guianensis. Leaves and branches of nine individuals of T. guianensis parasitized by P. perrottetii were also sampled. For each parasitized tree, we sampled an infested branch and its leaves, as well as a non-infested branch and its leaves. Infested branches were divided into three groups: gall (the host-parasite interface), proximal, and distal region. Both proanthocyanidins and ellagitanins seem to be important for plant-plant parasitism interaction: host infested tissues (gall and surrounding regions) have clearly less tannin contents than healthy tissues. Mistletoe showed high levels of quinic acid derivatives and flavonoids that could be important during hastorium formation and intrusion on host tissues, suggesting a defense mechanism that could promote oxidative stress together with an inhibition of mistletoe seed germination, consequently avoiding secondary infestations. Polyphenol detected in T. guianensis-P. perrottetii interaction could play different role as plant-mistletoe strategies of survival.


Assuntos
Anacardiaceae/parasitologia , Interações Hospedeiro-Parasita , Phoradendron/metabolismo , Polifenóis/metabolismo , Anacardiaceae/metabolismo , Flavonoides/metabolismo , Interações Hospedeiro-Parasita/fisiologia , Taninos Hidrolisáveis/metabolismo , Proantocianidinas/metabolismo , Ácido Quínico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Taninos/metabolismo
18.
Sci Total Environ ; 656: 1091-1101, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30625641

RESUMO

Passiflora edulis Sims is a liana species of high economic interest and is an interesting model plant for understanding ozone action on disturbed vegetation. In this work we hypothesized that P. edulis has adaptive responses to oxidative stress that enable it to tolerate ozone damage based on its capacity to grow under a diversity of environmental conditions and to dominate disturbed areas. We exposed seedlings to three levels of ozone in a Free-Air Controlled Exposure (FACE) system (22, 41 and 58 ppb h AOT40 and 13.52, 17.24 and 20.62 mmol m-2 POD0, over 97 days) for identifying its tolerance mechanisms. Anatomical (leaf blade structure and fluorescence emission of chloroplast metabolites), physiological (leaf gas exchange, growth rate and biomass production) and biochemical (pigments, total sugars, starch, enzymatic and non-enzymatic antioxidant metabolites, reactive oxygen species and lipid peroxidation derivatives) responses were assessed. Ozone caused decreased total number of leaves, hyperplasia and hypertrophy of the mesophyll cells, and accelerated leaf senescence. However, O3 did not affect carbohydrates content, net photosynthetic rate, or total biomass production, indicating that the carboxylation efficiency and associated physiological processes were not affected. In addition, P. edulis showed higher leaf contents of ascorbic acid, glutathione (as well high ratio between their reduced and total forms), carotenoids, and flavonoids located in the chloroplast outer envelope membrane. Our results indicate that P. edulis is an O3-tolerant species due to morphological acclimation responses and an effective antioxidant defense system represented by non-enzymatic antioxidants, which maintained the cellular redox balance under ozone.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Ozônio/efeitos adversos , Passiflora/efeitos dos fármacos , Relação Dose-Resposta a Droga , Passiflora/anatomia & histologia , Passiflora/química , Passiflora/fisiologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Plântula/anatomia & histologia , Plântula/química , Plântula/efeitos dos fármacos , Plântula/fisiologia
19.
Environ Pollut ; 152(2): 361-5, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17683837

RESUMO

Tibouchina pulchra saplings were exposed to carbon filtered air (CF), ambient non-filtered air (NF) and ambient non-filtered air+40 ppb ozone (NF+O3) 8 h per day during two months. The AOT40 values at the end of the experiment were 48, 910 and 12,895 ppb h(-1), respectively, for the three treatments. After 25 days of exposure (AOT40=3871 ppb h(-1)), interveinal red stippling appeared in plants in the NF+O3 chamber. In the NF chamber, symptoms were observed only after 60 days of exposure (AOT40=910 ppb h(-1)). After 60 days, injured leaves per plant corresponded to 19% in NF+O3 and 1% in the NF treatment; and the average leaf area injured was 7% within the NF+O3 and 0.2% within the NF treatment. The extent of leaf area injured (leaf injury index) was mostly explained by the accumulated exposure of ozone (r2=0.89; p<0.05).


Assuntos
Poluentes Atmosféricos/toxicidade , Melastomataceae/efeitos dos fármacos , Ozônio/toxicidade , Folhas de Planta/efeitos dos fármacos , Biomassa , Brasil , Exposição Ambiental , Monitoramento Ambiental/métodos , Plântula , Clima Tropical
20.
J. health sci. (Londrina) ; 25(2): 113-118, 20230630.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1510197

RESUMO

COVID-19 pandemic can have a significant impact on an individual's physical and emotional well-being. However, it is important to note that not all experiences of the pandemic are negative. This study aims to evaluate the perception of quality of life of students enrolled in a nursing course during the COVID-19 pandemic by administering a global questionnaire. A quantitative, exploratory, cross-sectional, and descriptive study to investigate perception of quality of life of students during the COVID-19 pandemic. Participants comprised 80 students graduating with a nursing qualification between 2020 and 2021. The Ferrans and Powers Quality of Life Index was used in the study. The mean scores are reported as follows: health/functioning domain (22.06), socioeconomic domain (21.40), psychological/spiritual domain (23.34), and family domain (23.06), with an average general quality of life index of 22.46. After evaluating the domains, it was found that there was a higher perception of the psychological/spiritual domain and lower perception of the socioeconomic domain. The results supported the internal consistency reliability of the entire Quality of Life (QLI; alpha=0.95) and the four subscales (alpha=0.88, 0.71, 0.92, and 0.80). The study suggests that the COVID-19 pandemic did not have an impact on the perceived quality of life among students.(AU)


Pandemia de COVID-19 pode ter um impacto significativo no bem-estar físico e emocional de um sujeito. No entanto, é importante notar que nem todas as experiências da pandemia são negativas. Este estudo teve como objetivo avaliar a percepção da qualidade de vida de estudantes matriculados em um curso de enfermagem durante a pandemia de COVID-19 por meio da aplicação de um questionário global. Estudo quantitativo, exploratório, transversal e descritivo para investigar a percepção da qualidade de vida de escolares durante a pandemia de COVID-19. Participaram 80 estudantes concluintes do curso de enfermagem entre 2020 e 2021. O Índice de Qualidade de Vida de Ferrans e Powers foi utilizado no estudo. Os escores médios foram relatados da seguinte forma: domínio saúde/funcionamento (22,06), domínio socioeconômico (21,40), domínio psicológico/espiritual (23,34) e domínio família (23,06), com média geral do índice de qualidade de vida de 22,46. Após a avaliação dos domínios, constatou-se maior percepção do domínio psicológico/espiritual e menor percepção do domínio socioeconômico. Os resultados apoiaram a confiabilidade da consistência interna de toda a Qualidade de Vida (QLI; alfa=0,95) e as quatro subescalas (alfa=0,88, 0,71, 0,92 e 0,80). O estudo sugere que a pandemia de COVID-19 não teve impacto na qualidade de vida percebida entre os estudantes.(AU)

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