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1.
Artigo em Inglês | MEDLINE | ID: mdl-39147299

RESUMO

Mammalian and reptilian vascular tissues present basal release of 6-nitrodopamine, which is reduced when the tissues are pre-incubated with the NO synthase inhibitor L-NG-Nitro arginine methyl ester (L-NAME), or when the endothelium is mechanically removed. 6-Nitrodopamine induces vasorelaxation in pre-contracted vascular rings by antagonizing the dopaminergic D2-like receptor. Here it was investigated whether male swine vessels (including carotid, left descendent coronary, renal, and femoral arteries) release 6-nitrodopamine, dopamine, noradrenaline, and adrenaline, as measured by liquid chromatography coupled to tandem mass spectrometry. The in vitro vasorelaxant action of 6-nitrodopamine was evaluated in carotid, coronary, renal, and femoral arteries precontracted by U-46619 (3 nM), and compared to that induced by the dopamine D2-receptor antagonist L-741,626. Expression of tyrosine hydroxylase and the neuromaker calretinin was investigated by immunohistochemistry. All vascular tissues presented basal release of endothelium-derived catecholamines. The relaxation induced by 6-nitrodopamine was not affected by preincubation of the tissues with either L-NAME (100 µM, 30-min preincubation) or the heme-site inhibitor of soluble guanylyl cyclase ODQ (100 µM, 30-min preincubation). Electrical field stimulation (EFS)-induced contractions were significantly potentiated by previous incubation with L-NAME, but unaffected by ODQ preincubation. The contractions induced by EFS were reduced by preincubation with either 6-nitrodopamine or L-741,626. Immunohistochemistry in all arteries revealed the presence of tyrosine hydroxylase in the endothelium, whereas immunoreactivity for calretinin was negative. Swine vessels present basal release of endothelium-derived catecholamines and expression of tyrosine hydroxylase in the endothelium. The vasodilation induced by 6-nitrodopamine is due to blockade of dopaminergic D2-like receptors.


Assuntos
Vasodilatação , Animais , Masculino , Vasodilatação/efeitos dos fármacos , Suínos , Artéria Femoral/efeitos dos fármacos , Artéria Femoral/metabolismo , Artéria Femoral/fisiologia , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/fisiologia , Vasos Coronários/metabolismo , Artéria Renal/efeitos dos fármacos , Artéria Renal/metabolismo , Artéria Renal/fisiologia , Dopamina/metabolismo , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/metabolismo , Artérias Carótidas/fisiologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiologia , Vasodilatadores/farmacologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-39008629

RESUMO

This study aimed to develop and validate a multi-mycotoxin analysis method applied to cashew nuts by employing a miniaturized QuEChERS method followed by determination by ultra-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Satisfactory recoveries for the concentrations 1, 10 and 30 ng g-1, ranging from 66% (fumonisin B1) to 110% (ochratoxin A) and relative standard deviations lower than 9% (fumonisin B2) were obtained for the target compounds. Limits of quantification ranged from 0.004 ng g-1 (sterigmatocystin) to 0.59 ng g-1 (alternariol). The applicability of the analytical method was verified by analyzing 30 cashew nut samples from the city of Rio de Janeiro, RJ, southeastern Brazil. Aflatoxins M1, G2, G1, B2, B1, ochratoxin A and sterigmatocystin were detected, respectively, in 27%, 10%, 17%, 30%, 30%, 30% and 50% of the analyzed samples, at maximum concentrations of 0.56, 0.67, 1.43, 2.02, 4.93, 4.81, and 0.35 ng g-1. The maximum limit established by Brazilian legislation for aflatoxins was not exceeded by any of the analyzed samples.


Assuntos
Anacardium , Contaminação de Alimentos , Micotoxinas , Nozes , Espectrometria de Massas em Tandem , Micotoxinas/análise , Anacardium/química , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Nozes/química , Aflatoxinas/análise , Espectrometria de Massa com Cromatografia Líquida
3.
Arch Toxicol ; 98(10): 3491-3502, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38951190

RESUMO

Snake venoms are complex mixtures majorly composed of proteins with well-studied biological effects. However, the exploration of non-protein components, especially lipids, remains limited despite their potential for discovering bioactive molecules. This study compares three liquid-liquid lipid extraction methods for both chemical and biological analyses of Bothrops moojeni snake venom. The methods evaluated include the Bligh and Dyer method (methanol, chloroform, water), considered standard; the Acunha method, a modification of the Bligh and Dyer protocol; and the Matyash method (MTBE/methanol/water), featuring an organic phase less dense than the aqueous phase. Lipidomic analysis using liquid chromatography with high-resolution mass spectrometry (LC-HRMS) system revealed comparable values of lipid constituents' peak intensity across different extraction methods. Our results show that all methods effectively extracted a similar quantity of lipid species, yielding approximately 17-18 subclasses per method. However, the Matyash and Acunha methods exhibited notably higher proportions of biologically active lipids compared to the Bligh and Dyer method, particularly in extracting lipid species crucial for cellular structure and function, such as sphingomyelins and phosphatidylinositol-phosphate. In conclusion, when selecting a lipid extraction method, it is essential to consider the study's objectives. For a biological approach, it is crucial to evaluate not only the total quantity of extracted lipids but also their quality and biological activity. The Matyash and Acunha methods show promise in this regard, potentially offering a superior option for extracting biologically active lipids compared to the Bligh and Dyer method.


Assuntos
Bothrops , Lipidômica , Lipídeos , Animais , Lipídeos/análise , Lipídeos/química , Lipidômica/métodos , Venenos de Crotalídeos/química , Cromatografia Líquida/métodos , Extração Líquido-Líquido/métodos , Espectrometria de Massas
4.
Chemosphere ; 363: 142725, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38945225

RESUMO

Benzophenone-3 (BP-3), utilized as a UV filter in cosmetic products, is an emerging contaminant that constitutes a threat to natural resources and environmental health. This study investigated the assimilation of the UV filter BP-3 in Crassostrea gigas oysters collected in Florianópolis, Santa Catarina, Brazil. Lyophilized oyster tissue extracts were prepared using the QuEChERS method, and LC-MS/MS was employed to determine the BP-3 concentration in the samples. The method was applied to specimens intentionally exposed to two concentrations of the contaminant, for different periods of exposure (1 and 7 days). Samples from treatment 1 (T1) were exposed to a concentration of 1 µg L-1 of the BP-3 standard, and samples from treatment 2 (T2) were exposed to a concentration of 100 µg L-1 of the BP-3 standard. The results revealed rapid absorption of BP-3, with an increase of 126% for lower concentrations, reaching 1.13 µg of BP-3 per gram of oyster tissue, and 17% for higher concentrations, reaching 34.6 µg of BP-3 per gram of oyster tissue after 7 days. The presence of BP-3 even in samples not directly exposed to the contaminant indicates its widespread environmental distribution. The rapid bioaccumulation suggests the need to consider seasonal variations, such as increased tourism in the summer. The validated analytical method demonstrated efficacy in quantifying BP-3, providing an integrated approach for long-term monitoring of pollution levels and their dynamic variations over time. In addition, variation in BP-3 levels in the samples may be related to transport patterns influenced by tides and discharges from septic system, highlighting the need to improve wastewater treatment. These findings underscore the necessity for continuous biomonitoring and effective environmental management to safeguard the health of marine ecosystems and humans.


Assuntos
Benzofenonas , Crassostrea , Protetores Solares , Poluentes Químicos da Água , Animais , Benzofenonas/análise , Benzofenonas/metabolismo , Benzofenonas/toxicidade , Brasil , Crassostrea/metabolismo , Crassostrea/efeitos dos fármacos , Monitoramento Ambiental/métodos , Espectrometria de Massa com Cromatografia Líquida , Protetores Solares/análise , Protetores Solares/metabolismo , Protetores Solares/toxicidade , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
5.
Artigo em Inglês | MEDLINE | ID: mdl-38940750

RESUMO

Bakery products, including biscuits, cakes and breads, generally present a high content of simple sugars of rapid absorption, high fat content and low amount of dietary fiber, which make them highly caloric foods. Although sucrose is a very important ingredient in bakery products for its preservation characteristics and a significant source of energy, there is a growing interest in replacing this sugar with alternative substances, such as high-intensity sweeteners (HIS) that provide sweetness with no or low calories. In Brazil, there is no data on the use of HIS in this class of food. Therefore, the objective of this study was to evaluate the presence of HIS in baked food commercially available in the country and estimate the dietary exposure to these food additives. For that, an analytical method was established for the simultaneous determination of nine HIS in bakery products using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Sample preparation steps were required based on mechanical kneading for homogenization, hexane extraction of fats, dilution in mobile phase and vortex homogenization, prior to injection into the system. The results obtained during validation showed that coefficients of variation (CV%) for precision were lower than 13.8% and the accuracy was between 91.6% and 109.1%. Aspartame, acesulfame potassium, sodium cyclamate, saccharin, sucralose and steviol glycosides were found in the samples, used alone or in combinations of up five substances. Steviol glycosides were the most found HIS in biscuit samples, while sucralose was the most common sweetener in cake and bread samples. Analysis of product labels revealed only three different claims, .i.e. 'no sugar', 'no added sugar' and 'zero sugar', with the latter being found in 70% of the samples. Exposure to HIS through the consumption of bakery products estimated per eating occasion showed no concerns regarding toxicological risk.


Assuntos
Exposição Dietética , Edulcorantes , Espectrometria de Massas em Tandem , Edulcorantes/análise , Brasil , Humanos , Exposição Dietética/análise , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Pão/análise
6.
Food Chem ; 456: 139948, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38852444

RESUMO

The natural vanilla market, which generates millions annually, is predominantly dependent on Vanilla planifolia, a species characterized by low genetic variability and susceptibility to pathogens. There is an increasing demand for natural vanilla, prized for its complex, authentic, and superior quality compared to artificial counterparts. Therefore, there is a necessity for innovative production alternatives to ensure a consistent and stable supply of vanilla flavors. In this context, vanilla crop wild relatives (WRs) emerge as promising natural sources of the spice. However, these novel species must undergo toxicity assessments to evaluate potential risks and ensure safety for consumption. This study aimed to assess the non-mutagenic and non-carcinogenic properties of ethanolic extracts from V. bahiana, V. chamissonis, V. cribbiana, and V. planifolia through integrated metabolomic profiling, in vitro toxicity assays, and in silico analyses. The integrated approach of metabolomics, in vitro assays, and in silico analyses has highlighted the need for further safety assessments of Vanilla cribbiana ethanolic extract. While the extracts of V. bahiana, V. chamissonis, and V. planifolia generally demonstrated non-mutagenic properties in the Ames assay, V. cribbiana exhibited mutagenicity at high concentrations (5000 µg/plate) in the TA98 strain without metabolic activation. This finding, coupled with the dose-dependent cytotoxicity observed in WST-1 (Water Soluble Tetrazolium) assays, a colorimetric method that assesses the viability of cells exposed to a test substance, underscores the importance of concentration in the safety evaluation of these extracts. Kaempferol and pyrogallol, identified with higher intensity in V. cribbiana, are potential candidates for in vitro mutagenicity. Although the results are not conclusive, they suggest the safety of these extracts at low concentrations. This study emphasizes the value of an integrated approach in providing a nuanced understanding of the safety profiles of natural products, advocating for cautious use and further research into V. cribbiana mutagenicity.


Assuntos
Metabolômica , Extratos Vegetais , Vanilla , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Brasil , Vanilla/química , Humanos , Florestas , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Testes de Mutagenicidade , Simulação por Computador
7.
Chem Biodivers ; 21(8): e202400665, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38825721

RESUMO

Waltheria indica (Malvaceae) is a plant popularly used in folk medicine by traditional African and indigenous communities, and in various countries worldwide, to treat general inflammation. Several biological activities of this plant have been reported, including acetylcholinesterase inhibition and potential anti-human immunodeficiency virus (HIV), antinociceptive, analgesic, antifungal, anticancer, anti-inflammatory, leishmanicidal, trypanocidal, antioxidant, and antibacterial activities. The chemical profile of Waltheria indica was assessed by dereplication analysis using UPLC-MS/MS, and data acquisition was performed using chemoinformatics tools, such as Mass Spectrometry-Data Independent AnaLysis (MS-DIAL) and MS-FINDER softwares. The preprocessed data were sent to the GNPS to build a feature-based molecular network (FBMN). Thirty-three 4-quinolone alkaloids were annotated in the extracts and fractions of stems and roots, whereas 12 were annotated in the extracts and fractions of flowers and leaves. This represents an inaugural chemical investigation study employing UPLC-Q-TOF-MS/MS analysis, along with a molecular network approach, within this species and genus.


Assuntos
Alcaloides , Espectrometria de Massas em Tandem , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , 4-Quinolonas/química , 4-Quinolonas/farmacologia , 4-Quinolonas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Folhas de Planta/química , Raízes de Plantas/química , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/isolamento & purificação
8.
Front Public Health ; 12: 1336014, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38932775

RESUMO

Introduction: Pollution has emerged as a significant threat to humanity, necessitating a thorough evaluation of its impacts. As a result, various methods for human biomonitoring have been proposed as vital tools for assessing, managing, and mitigating exposure risks. Among these methods, urine stands out as the most commonly analyzed biological sample and the primary matrix for biomonitoring studies. Objectives: This review concentrates on exploring the literature concerning residual pesticide determination in urine, utilizing liquid and gas chromatography coupled with mass spectrometry, and its practical applications. Method: The examination focused on methods developed since 2010. Additionally, applications reported between 2015 and 2022 were thoroughly reviewed, utilizing Web of Science as a primary resource. Synthesis: Recent advancements in chromatography-mass spectrometry technology have significantly enhanced the development of multi-residue methods. These determinations are now capable of simultaneously detecting numerous pesticide residues from various chemical and use classes. Furthermore, these methods encompass analytes from a variety of environmental contaminants, offering a comprehensive approach to biomonitoring. These methodologies have been employed across diverse perspectives, including toxicological studies, assessing pesticide exposure in the general population, occupational exposure among farmers, pest control workers, horticulturists, and florists, as well as investigating consequences during pregnancy and childhood, neurodevelopmental impacts, and reproductive disorders. Future directions: Such strategies were essential in examining the health risks associated with exposure to complex mixtures, including pesticides and other relevant compounds, thereby painting a broader and more accurate picture of human exposure. Moreover, the implementation of integrated strategies, involving international research initiatives and biomonitoring programs, is crucial to optimize resource utilization, enhancing efficiency in health risk assessment.


Assuntos
Monitoramento Biológico , Resíduos de Praguicidas , Humanos , Resíduos de Praguicidas/urina , Resíduos de Praguicidas/análise , Monitoramento Biológico/métodos , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas/métodos , Exposição Ambiental/análise , Cromatografia Líquida
9.
Biomed Chromatogr ; 38(8): e5896, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38797868

RESUMO

The aim of this study was to develop a high-performance liquid chromatography-tandem mass spectrometry method for the determination of 6-cyanodopamine, 6-nitrodopamine, 6-nitrodopa, 6-nitroadrenaline and 6-bromodopamine in human plasma samples. Strata-X 33 µm solid-phase extraction cartridges were used for the extraction of the catecholamines from human plasma samples. The catecholamines were separated in a 150 × 3 mm Shim-pack GIST C18-AQ column with 3 µm particle size, placed in an oven at 40°C and perfused with 82% mobile phase A (acetonitrile-H2O; 90:10, v/v) + 0.4% acetic acid and 18% mobile phase B (deionized H2O) + 0.2% formic acid at a flow rate of 340 µl/min in isocratic mode. The injected volume was 4 µl and the run lasted 4 min. The method was linear from 0.1 to 20 ng/ml and the lower limit of quantification was 0.1 ng/ml for all analytes. The method was applied to evaluate the plasma levels of catecholamines in plasma of patients with chronic kidney disease and allowed the detection for the first time of circulating levels of the novel catecholamines 6-bromodopamine and 6-cyanodopamine.


Assuntos
Limite de Detecção , Insuficiência Renal Crônica , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , Modelos Lineares , Insuficiência Renal Crônica/sangue , Cromatografia Líquida de Alta Pressão/métodos , Masculino , Cromatografia Líquida/métodos , Extração em Fase Sólida/métodos , Dopamina/sangue , Dopamina/análogos & derivados , Catecolaminas/sangue , Pessoa de Meia-Idade , Espectrometria de Massa com Cromatografia Líquida
10.
J Chromatogr A ; 1726: 464967, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38749275

RESUMO

Infant formulas (IF) can contain harmful chemical substances, such as pesticides and mycotoxins, resulting from the contamination of raw materials and inputs used in the production chain, which can cause adverse effects to infants. Therefore, the quick, easy, cheap, effective, rugged, and safe (QuEChERS) methodology prior ultra-high performance liquid chromatography coupled to triple quadrupole mass spectrometry (UHPL-QqQ-MS/MS) analysis was applied for the determination of 23 contaminants, in 30 samples of Brazilian IF. The method was validated in terms of limit of detection (0.2 to 0.4 µg/kg), limits of quantification (1 and 10 µg/kg), and recovery (64 % to 122 %); precision values, in terms of relative standard deviation (RSD), were ≤ 20 %. Fenitrothion, chlorpyrifos, and bifenthrin were the pesticides detected in the samples, but the values did not exceed the limit set by the European Union (EU), and ANVISA, and they were detected under their limits of quantification. Additionally, suspect screening and unknown analysis were conducted to tentatively identify 32 substances, including some compounds not covered in this study, such as pesticides, hormones, and veterinary drugs. Carbofuran was identified, confirmed and quantified in 10 % of the samples.


Assuntos
Contaminação de Alimentos , Fórmulas Infantis , Limite de Detecção , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Brasil , Fórmulas Infantis/química , Contaminação de Alimentos/análise , Praguicidas/análise , Humanos , Resíduos de Praguicidas/análise , Reprodutibilidade dos Testes , Micotoxinas/análise , Lactente , Piretrinas/análise
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