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1.
Drug Chem Toxicol ; : 1-11, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953234

RESUMO

Psychotria carthagenensis is a shrubby plant, often consumed by traditional populations in religious rituals. Previous studies have shown that this plant's infusion can inhibit the activity of Acetylcholinesterase (AChE) in rats. Despite the therapeutic potential, there is a lack of research regarding its possible toxicological and genotoxic effects. Hence, this study aimed to analyze the chemical profile of the ethanol extract from P. carthagenensis leaves by LC-DAD-MS and assess its possible toxicity and genotoxicity in zebrafish (Danio rerio). Adult zebrafish (N = 9/group) were exposed at different concentrations and the LC50 was calculated. Frequencies of micronucleus (MN) and nuclear abnormalities (NA) were estimated for genotoxic effects, and degree of tissue changes (DTC) was used to assess the liver and gill histopathology. From the LC-DAD-MS analyses, the identified compounds included N-fructosyl valine, ethyl hexoside, 5-O-E-caffeoylquinic acid, N-feruloylagmatime, roseoside, di-O-deoxyhexoyl-hexosyl quercetin, loiolide, and oleamide. The calculated values of LC50 did not vary significantly during the time of exposure. At the concentrations of 1.25, 2.5, 3.75, 5, 7.5, 10 and 15 mg/L, there was no genotoxicity, and only low to moderate toxicity for the tissues was observed, despite mortality of 100% at doses of 20-100 mg/L of P. carthagenensis ethanolic leaf extract. There were changes in cytoplasm of hepatocytes at 1.25 mg/L, and karyorrhexis, karyolysis and megalocytosis at 10 mg/L. In the gills, the alterations were primary lamellar hyperplasia in all concentrations, and at 10 mg/L, secondary lamellar edema and vascular hyperemia were common. Additionally, the chemical composition of P. carthagenensis was expanded.

2.
Chemosphere ; 268: 129334, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33360938

RESUMO

Synthetic manganese porphyrins (MnPs), in the presence of oxidants, were employed for the degradation of fluoroquinolone antibiotics. Ciprofloxacin (CIP) and levofloxacin (LEV) degradation by iodosylbenzene, iodobenzene diacetate, H2O2 and meta-chloroperbenzoic acid using water-soluble MnP catalysts yielded thirteen and nine products, respectively, seven of which have been proposed for the first time. The MnP catalysts have demonstrated the ability to degrade these antibiotics to a high degree (up to 100% degradation). The structures of the degradation products were proposed based on mass spectrometry analysis, and density functional theory calculations could confirm how the substituent moieties attached to the basic chemical structure of the fluoroquinolones influence the degradation reactions. CIP has been shown to be a more reactive substrate towards the porphyrinic catalysts tested because of its three-membered ring. However, the catalysts could almost completely degrade LEV, highlighting the ability of these porphyrins to act as catalysts to degrade environmental pollutants.


Assuntos
Porfirinas , Poluentes Químicos da Água , Antibacterianos , Ciprofloxacina , Peróxido de Hidrogênio , Levofloxacino , Manganês , Solventes , Água
3.
Sci Total Environ ; 592: 693-703, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28341464

RESUMO

The Velhas River is the most polluted river in the state of Minas Gerais, south-eastern Brazil. Due to its historical and environmental relevance, the aim of this study was to evaluate the effects of oestrogenic endocrine disruptors on the reproduction of the lambari Astyanax rivularis, a small-sized species found in headwaters of the São Francisco River basin. Quarterly field samplings were carried out during a reproductive cycle in three streams of the upper Velhas River: S1 (reference site) and S2 and S3 (sites contaminated by untreated sewage). The main oestrogenic compounds were evaluated in water using HPLC/MS. Molecular, histological and reproductive biomarkers were assessed in liver and gonad. The results showed higher average concentrations of oestradiol (>200ng/l) in S2 and S3, oestrone (>250ng/l) in S2 as well as oestriol (>200ng/l), bisphenol A (>190ng/l), and nonylphenol (>600ng/l) in S3 compared to S1 (<70ng/l for all compounds). In S2 and S3, there was an increase in the proportion of females, higher ELISA levels of vitellogenin (Vtg) and proteins of the zona radiata (Zrp) in liver males. Insulin-like growth factor (IGF-I) levels were lower in S2 males, which also had a smaller body size, a smaller seminiferous tubule diameter, a higher proportion of spermatogonia, and lower proportion of spermatozoa in relation to S1. Histopathological analyses detected an increase in yolk deficient oocytes and over-ripening in the contaminated sites, and these alterations were associated to a reduction of hepatic Vtg levels and a delay in spawning, respectively. Intersex specimens with perinucleolar follicles in a multifocal distribution in the testis were detected in S2 and S3. These results indicate that chronic exposure to oestrogenic compounds induced endocrine disruption that may affect wild populations of A. rivularis in the Velhas River.


Assuntos
Characidae/fisiologia , Disruptores Endócrinos/toxicidade , Reprodução/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/análise , Brasil , Transtornos do Desenvolvimento Sexual/veterinária , Estrogênios/análise , Feminino , Fator de Crescimento Insulin-Like I/análise , Masculino , Rios , Vitelogeninas/análise
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