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1.
Bull Environ Contam Toxicol ; 108(3): 451-456, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33891141

RESUMO

Sustainable agricultural practices based on the development of native arbuscular mycorrhizal fungi (AMF) can improve crop growth and stress tolerance in acidic soils with manganese toxicity. The beneficial effects are stronger when crops are colonized early in development by an intact extraradical mycelium (ERM), but are dependent on AMF assemblage. In wheat colonized by AMF associated to Lolium rigidum L. (LOL) or Ornithopus compressus (ORN), growth and stress tolerance are differently influenced. In the present study, this functional diversity was studied by evaluating the activity of ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR), guaiacol peroxidase (GPX), superoxide dismutase (SOD) and Mn-SOD. ORN treatment promoted higher wheat shoot and root dry weights, a higher root protein content, decreased root APX, GR and SOD activities but a higher proportion of MnSOD activity. ORN associated microbiota differently manage antioxidant enzyme activity of succeeding wheat to improve growth.


Assuntos
Antioxidantes , Micorrizas , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Micélio/metabolismo , Micorrizas/metabolismo , Triticum/metabolismo
2.
Graefes Arch Clin Exp Ophthalmol ; 259(4): 873-882, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33074374

RESUMO

PURPOSE: To characterize morphological changes in the retina and to report the frequency and natural history of non-exudative macular neovascularization (MNV) in a cohort of pseudoxanthoma elasticum (PXE). METHODS: A single-center, retrospective study was complemented by a cross-sectional examination. Consecutive patients with a definitive genetic and/or clinical diagnosis of PXE, visiting our department between January 2019 and December 2019, and with a minimum follow-up of 6 months were recruited. Baseline data were retrieved from each patient file. Additionally, a cross-sectional examination comprising color fundus photography, spectral-domain optical coherence tomography (SD-OCT), OCT-Angiography (OCT-A), and fundus autofluorescence was performed. The presence of typical PXE-related findings, as well as related complications, was multimodally evaluated. The prevalence and natural history of non-exudative MNV were assessed. All images were graded by two independent graders. RESULTS: Forty-eight eyes from 24 patients (mean age 59.11 ± 18.14) with a median follow-up of 53.00 months were included. Angioid streaks and peau d'orange were observed in 46/48 and 42/48 eyes, while MNV was present in 75.00% of the cohort. The prevalence of non-exudative MNV was 33.33% (6/18). In the 2 eyes that developed exudation, time to conversion was 9.50 ± 4.95 months. No significant difference in visual acuity was found between eyes with non-exudative MNV and those with no signs of MNV. CONCLUSION: We have shown that non-exudative MNV is a frequent finding in PXE but the majority of eyes did not develop exudation during follow-up. Our results are a clear evidence of the utility of OCT-A in the management of PXE.


Assuntos
Neovascularização de Coroide , Pseudoxantoma Elástico , Neovascularização de Coroide/diagnóstico , Neovascularização de Coroide/epidemiologia , Neovascularização de Coroide/etiologia , Estudos Transversais , Angiofluoresceinografia , Humanos , Pessoa de Meia-Idade , Pseudoxantoma Elástico/complicações , Pseudoxantoma Elástico/diagnóstico , Estudos Retrospectivos , Tomografia de Coerência Óptica
3.
Ecotoxicol Environ Saf ; 193: 110355, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32120164

RESUMO

In the Montado system, in Portuguese Alentejo region, some Eutric Cambisols are known to promote manganese (Mn) toxicity in wheat. Variation on bioavailable Mn concentration depends on soil acidity, which can be increased by natural events (e.g. waterlogging) or human activity (e.g. excess use of chemical fertilizers). The effect of increasing soil Mn on crop element uptake, element distribution and oxidative stress was evaluated on winter wheat (Triticum aestivum). Plants were grown for 3 weeks in an acidic Cambisol spiked with increasing Mn concentrations (0, 45.2 and 90.4 mg MnCl2/Kg soil). Calcium (Ca), phosphorus (P), magnesium (Mg) and Mn were quantified in the soil solution, root and shoot tissues and respective subcellular fractions. The activity of the antioxidant enzymes ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR), guaiacol peroxidase (GPX) and superoxide dismutase (SOD) were determined in extracts of wheat shoots and roots. Overall, increase in soil bioavailable Mn inhibited the uptake of other elements, increased the Ca proportion in the root apoplast, promoted the translocation of Mn and P to shoot tissues and increased their proportion in the shoot vacuoles. Wheat roots showed greater antioxidant enzymes activities than shoots. These activities decreased at the highest soil Mn concentration in both plant parts. Wheat roots appear to be more sensitive to oxidative stress derived from excess soil Mn and promote Mn translocation and storage in shoot vacuoles, probably in Mn and P complexes, as a detoxification strategy. Improvement in wheat production, in acidic soils, may rely on the enhancement of its Mn detoxification strategies.


Assuntos
Manganês/toxicidade , Poluentes do Solo/toxicidade , Triticum/efeitos dos fármacos , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Transporte Biológico , Cálcio/metabolismo , Catalase/metabolismo , Glutationa Redutase/metabolismo , Magnésio/metabolismo , Manganês/farmacocinética , Estresse Oxidativo , Peroxidase/metabolismo , Fósforo/metabolismo , Solo/química , Poluentes do Solo/farmacocinética , Superóxido Dismutase/metabolismo , Triticum/enzimologia , Triticum/metabolismo
4.
Ophthalmologica ; 241(4): 226-233, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30654376

RESUMO

PURPOSE: To evaluate the influence of hydroxychloroquine in visual field and retinal layer thickness. METHODS: This is a retrospective cross-sectional study. Patients taking hydroxychloroquine without signs of hydroxychloroquine retinopathy were included. Optical coherence tomography segmentation was used to obtain the ETDRS map thickness of each retinal layer. Groups were divided into short-term (< 5 years) and long-term (≥5 years) drug use. RESULTS: We included 93 eyes of 93 patients (short-term: 25 eyes; long-term: 68 eyes). The inner nuclear layer (INL) was thinner in the long-term group (32.86 ± 2.12 vs. 34.14 ± 2.37 µm; p = 0.014). Considering long-term cases, the parafoveal ganglion cell layer (GCL) showed an inverse correlation with cumulative dose (r = -0.37; p < 0.001). After adjusting for confounders, parafoveal ganglion cell complex thickness was associated with cumulative dose (ß = -0.239; p = 0.011). The parafoveal outer retina and visual field indices were similar between groups and did not correlate with cumulative dose. CONCLUSION: Hydroxychloroquine leads to progressive thinning of the parafoveal inner retina, particularly the INL and GCL. Visual field indices do not reflect the long-term effects of the drug.


Assuntos
Fóvea Central/patologia , Hidroxicloroquina/efeitos adversos , Doenças Retinianas/induzido quimicamente , Células Ganglionares da Retina/efeitos dos fármacos , Acuidade Visual/efeitos dos fármacos , Campos Visuais/efeitos dos fármacos , Antirreumáticos/efeitos adversos , Estudos Transversais , Feminino , Fóvea Central/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Doenças Retinianas/diagnóstico , Células Ganglionares da Retina/patologia , Estudos Retrospectivos , Fatores de Risco , Tomografia de Coerência Óptica
5.
Microsc Microanal ; 22(5): 1007-1017, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27619477

RESUMO

A corrosion product rarely reported in the literature has been found on the copper support of three miniature paintings of the 17th and 18th centuries. This product, which has been identified as dicoppertrihydroxyformate (Cu2(OH)3HCOO), is an unusual basic copper formate found on copper artifacts. The identification and characterization of dicoppertrihydroxyformate was carried out directly over the corroded surface of the objects, using a nondestructive approach, which combines the integrated use of various microanalytical techniques. Using this approach, it was possible to obtain a set of new reference data about the natural form of Cu2(OH)3HCOO, that will enable its unambiguous identification in other similar objects. In this work, the probable causes that may have contributed to its formation are also discussed.

6.
Plants (Basel) ; 12(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37299071

RESUMO

Soil with excess Mn induces toxicity and impairs crop growth. However, with the development in the soil of an intact extraradical mycelia (ERM) from arbuscular mycorrhizal fungi (AMF) symbiotic to native Mn-tolerant plants, wheat growth is promoted due to a stronger AMF colonization and subsequent increased protection against Mn toxicity. To determine the biochemical mechanisms of protection induced by this native ERM under Mn toxicity, wheat grown in soil from previously developed Lolium rigidum (LOL) or Ornithopus compressus (ORN), both strongly mycotrophic plants, was compared to wheat grown in soil from previously developed Silene gallica (SIL), a non-mycotrophic plant. Wheat grown after LOL or ORN had 60% higher dry weight, ca. two-fold lower Mn levels and almost double P contents. Mn in the shoots was preferentially translocated to the apoplast along with Mg and P. The activity of catalase increased; however, guaiacol peroxidase (GPX) and superoxide dismutase (SOD) showed lower activities. Wheat grown after ORN differed from that grown after LOL by displaying slightly higher Mn levels, higher root Mg and Ca levels and higher GPX and Mn-SOD activities. The AMF consortia established from these native plants can promote distinct biochemical mechanisms for protecting wheat against Mn toxicity.

7.
Plants (Basel) ; 12(13)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37446999

RESUMO

Control of the pinewood nematode (PWN), the causal agent of pine wilt disease, can be achieved through the trunk injection of nematicides; however, many pesticides have been linked to environmental and human health concerns. Essential oils (EOs) are suitable alternatives due to their biodegradability and low toxicity to mammals. These complex mixtures of plant volatiles often display multiple biological activities and synergistic interactions between their compounds. The present work profiled the toxicity of eight EOs against the PWN in comparison to their 1:1 mixtures, to screen for successful synergistic interactions. Additionally, the main compounds of the most synergistic mixtures were characterized for their predicted environmental fate and toxicity to mammals in comparison to emamectin benzoate, a commercial nematicide used against PWN. The mixtures of Cymbopogon citratus with Mentha piperita and of Foeniculum vulgare with Satureja montana EOs showed the highest activities, with half-maximal effective concentrations (EC50) of 0.09 and 0.05 µL/mL, respectively. For these, complete PWN mortality was reached after only ca. 15 min or 2 h of direct contact, respectively. Their major compounds had a higher predicted affinity to air and water environmental compartments and are reported to have very low toxicity to mammals, with low acute oral and dermal toxicities. In comparison, emamectin benzoate showed lower nematicidal activity, a higher affinity to the soil and sediments environmental compartments and higher reported oral and dermal toxicity to mammals. Overall, uncovering synergistic activities in combinations of EOs from plants of different families may prove to be a source of biopesticides with optimized toxicity against PWNs.

8.
Environ Sci Pollut Res Int ; 24(5): 4871-4881, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27988897

RESUMO

Several biosurfactants with antagonistic activity are produced by a variety of microorganisms. Lipopeptides (LPPs) produced by some Bacillus strains, including surfactin, fengycin and iturin are synthesized nonribosomally by mega-peptide synthetase (NRPS) units and they are particularly relevant as antifungal agents. Characterisation, identification and evaluation of the potentials of several bacterial isolates were undertaken in order to establish the production of active lipopeptides against biodeteriogenic fungi from heritage assets. Analysis of the iturin operon revealed four open reading frames (ORFs) with the structural organisation of the peptide synthetases. Therefore, this work adopted a molecular procedure to access antifungal potential of LPP production by Bacillus strains in order to exploit the bioactive compounds synthesis as a green natural approach to be applied in biodegraded cultural heritage context. The results reveal that the bacterial strains with higher antifungal potential exhibit the same morphological and biochemical characteristics, belonging to the genera Bacillus. On the other hand, the higher iturinic genetic expression, for Bacillus sp. 3 and Bacillus sp. 4, is in accordance with the culture antifungal spectra. Accordingly, the adopted methodology combining antifungal screening and molecular data is represent a valuable tool for quick identification of iturin-producing strains, constituting an effective approach for confirming the selection of lipopeptides producer strains.


Assuntos
Antifúngicos/farmacologia , Desinfetantes/farmacologia , Lipopeptídeos , Bacillus/metabolismo , Bacillus subtilis , Fungos/metabolismo , Tensoativos
9.
Nat Prod Res ; 31(18): 2183-2187, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28076987

RESUMO

Essential oils (EOs) and aqueous extracts of aerial parts of four aromatic species, Calamintha nepeta, Foeniculum vulgare, Mentha spicata and Thymus mastichina, from southwest of Portugal were characterised chemically and analysed in order to evaluate their antioxidant potential and cholinesterase inhibitory activities. The main components of EOs were oxygenated monoterpenes, and aqueous extracts were rich in phenol and flavonoid compounds. EOs and aqueous extracts presented a high antioxidant potential, with ability to protect the lipid substrate, free radical scavenging and iron reducing power. Furthermore, EOs and extracts showed AChE and BChE inhibitory activities higher than rivastigmine, the standard drug. Results suggested the potential use of EOs and aqueous extracts of these flavouring herbs as nutraceutical or pharmaceutical preparations to minimise the oxidative stress and the progression of degenerative diseases.


Assuntos
Antioxidantes/farmacologia , Inibidores da Colinesterase/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Antioxidantes/química , Inibidores da Colinesterase/química , Avaliação Pré-Clínica de Medicamentos/métodos , Flavonoides/análise , Aromatizantes/química , Foeniculum/química , Lamiaceae , Mentha spicata/química , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Fenóis/análise , Extratos Vegetais/química , Portugal , Thymus (Planta)/química
10.
J Chromatogr A ; 1129(1): 14-20, 2006 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-16893546

RESUMO

Cassis, a commercial powder obtained from blackcurrant juice (Ribes nigrum L.), was used to optimize the anthocyanin extraction by matrix solid-phase dispersion (MSPD) and by sea sand disruption method (SSDM). The optimum eluent conditions were 5.0 mL of MeOH/H2O (1:1, v/v) at pH 2. The extracts were analyzed by HPLC with diode-array detection (DAD) and the extraction efficiency was evaluated by statistical comparison (analysis of variance, ANOVA-single factor) of the compounds peak areas. The extraction efficiency for the MSPD procedure was dependent on the chemical nature of the C18 material but the optimized procedure yielded results similar to those obtained by the inexpensive sea sand disruption method (SSDM). This procedure also compared favorably to a previously published liquid-liquid extraction method. The optimized sea sand method was then used in the anthocyanin extraction from red grapes (Vitis vinifera L.) and strawberries (Fragaria ananassa D.) yielding chromatographic profiles similar to those reported in the literature for these products.


Assuntos
Antocianinas/análise , Fracionamento Químico/métodos , Verduras/química , Antocianinas/química , Antocianinas/isolamento & purificação , Cromatografia Líquida/métodos , Frutas/química , Estrutura Molecular , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/métodos
11.
Bioresour Technol ; 101(3): 886-92, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19783427

RESUMO

Microcosm constructed wetlands systems established with a matrix of light expanded clay aggregates (LECA) and planted with Typha spp. were used to evaluate their ability to remove pharmaceuticals ibuprofen, carbamazepine and clofibric acid from wastewaters. Seasonal variability of these systems' performances was also evaluated. Overall, removal efficiencies of 96%, 97% and 75% for ibuprofen, carbamazepine and clofibric acid, respectively, were achieved under summer conditions after a retention time of 7 days. In winter, a maximum loss of 26% in removal efficiency was observed for clofibric acid. Removal kinetics was characterized by a fast initial step (>50% removal within 6h) mainly due to adsorption on LECA but, on a larger timescale, plants also contributed significantly to the system's performance. Despite the fact that further tests using larger-scale systems are required, this study points to the possible application of these low-cost wastewater treatment systems for dealing with pharmaceuticals contaminated wastewater.


Assuntos
Preparações Farmacêuticas/isolamento & purificação , Typhaceae/metabolismo , Purificação da Água/métodos , Áreas Alagadas , Adsorção , Silicatos de Alumínio/química , Biodegradação Ambiental , Carbamazepina/isolamento & purificação , Argila , Ácido Clofíbrico/isolamento & purificação , Ibuprofeno/isolamento & purificação , Resíduos Industriais , Cinética , Fatores de Tempo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação
12.
Anal Chim Acta ; 674(2): 182-9, 2010 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-20678628

RESUMO

A multi-walled carbon nanotubes (MWCNTs) film-coated glassy carbon electrode (GCE) was used for the voltammetric determination of carbamazepine (CBZ). The results showed that this simple modified electrode exhibited excellent electrocatalytic activity towards the oxidation of CBZ. The voltammetric response of CBZ at this film-modified electrode increased significantly when compared with that at a bare glassy carbon electrode and the sensor response was reproducible. The proposed method was applied to the quantification of CBZ in wastewater samples, collected in a municipal wastewater treatment plant, and in pharmaceutical formulations. The developed methodology yields results in accord with those obtained by chromatographic techniques commonly used in the quantification of pharmaceutical compounds in real samples. Good recoveries have been obtained and the limits of detection and quantification (40 and 140 nM, respectively) are among the lowest that have been reported to date for this pharmaceutical compound using voltammetric techniques.


Assuntos
Anticonvulsivantes/análise , Carbamazepina/análise , Eletroquímica/instrumentação , Nanotubos de Carbono/química , Preparações Farmacêuticas/química , Poluentes Químicos da Água/análise , Calibragem , Eletrodos , Limite de Detecção , Oxirredução
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