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1.
Environ Technol ; 43(17): 2612-2619, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33583355

RESUMO

In this study, we have applied Fe(III)-bi-carboxylic acid solutions containing citrate and oxalate ligands to degrade 3-méthylphénol (3MP) in aqueous solutions both under UV and sunlight. Under irradiation at 365 nm, the photodegradation of 3MP is markedly better in the presence of the Fe(III)Ox complex than in the Fe(III)Cit complex this fact is explained by an excess of H2O2 and Fe(II) generated by Fe(III)Ox photolysis creating the Fenton process. We mixtures were realized by varying the composition of the Fe(III)Cit and Fe(III)Ox in order to see the additives of the degradation efficiency of the pollutant. The results show that the addition of Fe(III)Ox to the Fe(III)Cit system evidently augmented the photodegradation rate at pH = 5.5. The Fe(III)Ox/Fe(III)Cit ratio is optimized at [Fe(III)Ox] (0.15/0.15)/[Fe(III)Cit] (0.15/0.6). Synergistic effect in the Fe(III)Ox/Fe(III)Cit binary system was confirmed. The addition of tertiobutanol (T-buOH) noticeably inhibited the photodegradation, indicating the involvement of •OH in the process. To verify the feasibility of photochemical processes in the environment, tests on the photodegradation of 3MP were performed under natural irradiation. The degradation was improved under excitation by sunlight in the presence of Fe(III)-bi-carboxylic acid solutions containing citrate and oxalate ligands. These results are very encouraging for the application of this system for the treatment of organic pollutants in aqueous solution.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Ácidos Carboxílicos , Citratos , Ácido Cítrico/química , Compostos Férricos/química , Peróxido de Hidrogênio/química , Ligantes , Compostos Orgânicos , Oxalatos/química , Fotólise , Luz Solar , Água/química , Poluentes Químicos da Água/química
2.
Exp Toxicol Pathol ; 64(7-8): 689-95, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21288705

RESUMO

Zearalenone (ZEN) is a non-steroidal estrogenic mycotoxin produced by several species of Fusarium in cereals and agricultural products. It has been implicated in several mycotoxicosis in farm animals and in humans. Several reports suggest that oxidative damage seems to be a key determinant of ZEN induced toxicity in vitro and in vivo. The aim of the current study was to evaluate the protective effects of aqueous extract of Allium sativum (AEA), against ZEN-induced cytotoxicity, reactive oxygen species (ROS) generation and DNA fragmentation in cultured Vero cells. Indeed, cytotoxicity effects were studied using MTT viability assay, ROS generation measurement and catalase activity induction. To check whether the oxidative stress induction was associated to DNA lesions, we looked for DNA fragmentation using Comet test. Our results indicated that ZEN induced several toxic effects and significant alterations mediated by oxidative stress mechanism. Treatment by ZEN combined to the lowest dose of AEA (250 µg/ml) showed a significant reduction of ZEN induced damages for all tested markers and a noticeable reduction of DNA fragmentation. It could be concluded that A. sativum aqueous extracts is effective in the protection against ZEN hazards. This could be relevant, particularly with the emergent demand for natural products which may counteract the detrimental toxic effects mediated by oxidative stress process and therefore prevents multiple human diseases.


Assuntos
Estrogênios não Esteroides/toxicidade , Sequestradores de Radicais Livres/farmacologia , Alho/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Zearalenona/toxicidade , Animais , Catalase/metabolismo , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Ensaio Cometa , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sequestradores de Radicais Livres/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Superóxidos/metabolismo , Células Vero , Xantina Oxidase/antagonistas & inibidores
3.
J Biochem Mol Toxicol ; 23(4): 233-43, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19705349

RESUMO

Zearalenone (ZEN) is a fusarotoxin converted predominantly into alpha-zearalenol (alpha-Zol) and beta-zearalenol (beta-Zol) by hepatic hydroxysteroid dehydrogenases. The feeding of naturally contaminated grains with ZEN was associated with hyperestrogenic and adverse effects on humans and animals. There is a lack of information on the attribution of the toxic effects of these toxins. One wonders if these effects are due to the parent molecule (ZEN) or to its major metabolites (alpha-Zol and beta-Zol). Using human Caco-2 cells, we looked for the molecular mechanisms of toxicity of ZEN, alpha-Zol, and beta-Zol. Toxicity effects were studied by MTT viability assay and oxidative stress induction by measuring malondialdehyde (MDA) generation. To check whether the oxidative stress induction was associated to DNA lesions, we looked for DNA fragmentation by means of the Comet and the diphenylamine assays. To specify cell death pathway, we investigated caspase-3 activation, confirmed by poly(ADP-ribose) polymerase cleavage and by Bcl-2 depletion. Our results clearly demonstrated that ZEN as well as its two metabolites presented variable toxic effects. They induced cell death and an increase in MDA generation. These effects were associated to DNA fragmentation as well as caspase-3 activation. The observed toxic effects seem to be relieved by the metabolism of ZEN into alpha-Zol and beta-Zol.


Assuntos
Zearalenona/toxicidade , Zeranol/análogos & derivados , Células CACO-2 , Caspase 3/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Dano ao DNA , Fragmentação do DNA/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Genoma Humano/genética , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Zearalenona/química , Zeranol/química , Zeranol/toxicidade
4.
Toxicon ; 48(3): 343-52, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16884754

RESUMO

T-2 toxin belongs to a group of mycotoxins synthesized by Fusarium fungi that are widely encountered as natural contaminants of certain important agricultural commodities particularly, cereals. Upon exposure, T-2 toxin causes severe human and animal diseases. It is considered to be a major causative agent in fatal alimentary toxic aleukia (ATA) in humans. In this study, cytotoxicity and apotosis induction by T-2 toxin was investigated in vitro on Vero cell line using the MTT and the neutral red viability assays, the induction of lipid peroxidation, the decrease of macromolecule levels (protein, DNA and RNA), DNA fragmentation and caspase-3-dependent apoptosis induction. Our results showed that T-2 toxin reduced cell viability correlated to an impairment of macromolecule levels. It also increased MDA formation, induced DNA fragmentation showed by DNA laddering patterns on agarose gel electrophoresis. This fragmentation is in relation with apoptosis induction which was confirmed by activation of caspase-3, and depletion of the mitochondrial membrane potential reflecting a mitochondrial dysfunction.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Toxina T-2/toxicidade , Animais , Apoptose/efeitos dos fármacos , Caspase 3 , Caspases/metabolismo , Chlorocebus aethiops , DNA/efeitos dos fármacos , Eletroforese em Gel de Ágar , Ativação Enzimática , Peroxidação de Lipídeos/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , RNA/efeitos dos fármacos , Células Vero
5.
Eur J Intern Med ; 12(6): 522-4, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11711277

RESUMO

Carcinoma of the breast is relatively rare among men, accounting for less than 1% of all malignancies. An increased risk has been associated with benign breast diseases, such as gynecomastia, Klinefelter's syndrome, testicular disorders, exogenous estrogen use, radiation, or a family history of male or female breast cancer. To date, hypogonadotrophic hypogonadism has never been associated with male breast cancer. We report here the first case of breast cancer coexisting with Kallmann's syndrome in a 66-year-old man.

6.
Presse Med ; 21(29): 1364-8, 1992 Sep 12.
Artigo em Francês | MEDLINE | ID: mdl-1454765

RESUMO

In order to validate the information systems medicalization program used since 1984 at the Hôtel-Dieu hospital, Paris, the direct costs given by this program were compared with those calculated from the medical records of 10 adult patients hospitalized for diagnosis and treatment of acute myeloblastic leukaemia. The mean direct cost of an 8 to 81 days hospital stay was estimated at 75.393 +/- 41.260 French francs by the program and 84.969 +/- 52.288 FF by calculations from the records. A fairly good correlation (r2 = 0.72; P = 0.002) was found between the 2 evaluations. There was no statistically significant difference between the figures obtained by the 2 methods, except for pharmaceutical expenditures (P = 0.005) which were grossly underevaluated by the program. A better correlation could be obtained if an attribution of drugs and transfusions per patient was entered in the program.


Assuntos
Efeitos Psicossociais da Doença , Sistemas de Informação Hospitalar , Leucemia Mieloide Aguda/economia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , França , Humanos , Tempo de Internação , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade
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