Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
J Water Health ; 16(4): 635-645, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30067244

RESUMO

Exposure to various endocrine disrupting chemicals (EDCs) can lead to adverse effects on reproductive physiology and behavior in both animals and humans. An adequate strategy for the prevention of environmental contamination and eliminating the effects of them must be established. Chemicals with estrogenic activity were selected, and the effectiveness of their removal during the purification processes in two drinking water treatment plants (DWTPs) using riverbank infiltrated water was determined. Thirty-five water samples in two sampling campaigns throughout different seasons were collected and screened with a yeast estrogen test; furthermore, bisphenol A (BPA), 17ß-estradiol (E2) and ethinyl-estradiol (EE2) content were measured using high-performance liquid chromatography-mass spectrometry (HPLC-MS). Our results confirm that estrogenic compounds are present in sewage effluents and raw surface river water of DWTPs. Very low estrogen activity and pg/L concentrations of BPA and E2 were detected during drinking water processing and occasionally in drinking water. Based on this study, applied riverbank filtration and water treatment procedures do not seem to be suitable for the total removal of estrogenic chemicals. Local contamination could play an important role in increasing the BPA content of the drinking water at the consumer endpoint.


Assuntos
Compostos Benzidrílicos/farmacologia , Disruptores Endócrinos/química , Estradiol/farmacologia , Fenóis/farmacologia , Rios/química , Poluentes Químicos da Água/farmacologia , Leveduras/efeitos dos fármacos , Compostos Benzidrílicos/química , Disruptores Endócrinos/farmacologia , Estradiol/química , Fenóis/química , Poluentes Químicos da Água/química
2.
Open Med Chem J ; 12: 13-22, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29492167

RESUMO

BACKGROUND: Non-enzymatic hydroxylation of aromatic compounds to the respective phenolic derivatives is a possible metabolic pathway of xenobiotics. The formed metabolites can undergo consecutive oxidative reactions with free radicals to form potential toxic molecules. OBJECTIVE: Development of HPLC methods to separate, identify and quantitate the main products formed from salicylic acid, 2,3-dihydroxybenzoic acid and 2,5-dihydroxybenzoic acid under in vitro hydroxylation conditions (Udenfriend's system). METHOD: An RP-HPLC-UV-Vis method was developed to separate salicylic acid and isomeric dihydroxybenzoic acids formed in the Udenfriend's system. Confirmation of structures of the oxidized products of salicylic acid, 2,3-dihydroxybenzoic acid and 2,5-dihydroxybenzoic acid was performed by HPLC-ESI-MS/MS method. RESULTS: The HPLC-UV-Vis method was evaluated for a number of validation characteristics (selectivity, repeatability and intermediate precision, LOD, LOQ and calibration range). It was found that oxidation of salicylic acid resulted in the formation of 2,3- and 2,5-dihydroxybenzoic acids. Furthermore, the hydroxylated metabolites can be further metabolized under the Udenfriend's conditions. CONCLUSION: The results give evidence for possible involvement of the oxidized metabolites of salicylic acid in the development of biological action of salicylates at the site of inflammation, where high hydroxyl radical level can be detected.

3.
Environ Sci Pollut Res Int ; 23(12): 11630-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26936475

RESUMO

17ß-Estradiol (E2) and 17α-ethinyl estradiol (EE2), which are environmental estrogens, have been determined with LC-MS in freshwater. Their sensitive analysis needs derivatization and therefore is very hard to achieve in multiresidue screening. We analyzed samples from all the large and some small rivers (River Danube, Drava, Mur, Sava, Tisza, and Zala) of the Carpathian Basin and from Lake Balaton. Freshwater was extracted on solid phase and derivatized using dansyl chloride. Separation was performed on a Kinetex XB-C18 column. Detection was achieved with a benchtop orbitrap mass spectrometer using targeted MS analysis for quantification. Limits of quantification were 0.05 ng/L (MS1) and 0.1 ng/L (MS/MS) for E2, and 0.001 ng/L (MS1) and 0.2 ng/L (MS/MS) for EE2. River samples contained n.d.-5.2 ng/L E2 and n.d.-0.68 ng/L EE2. Average levels of E2 and EE2 were 0.61 and 0.084 ng/L, respectively, in rivers, water courses, and Lake Balaton together, but not counting city canal water. EE2 was less abundant, but it was still present in almost all of the samples. In beach water samples from Lake Balaton, we measured 0.076-0.233 E2 and n.d.-0.133 EE2. A relative high amount of EE2 was found in river Zala (0.68 ng/L) and in Hévíz-Páhoki canal (0.52 ng/L), which are both in the catchment area of Lake Balaton (Hungary).


Assuntos
Estradiol/análise , Estrogênios/análise , Etinilestradiol/análise , Rios/química , Poluentes Químicos da Água/análise , Cromatografia Líquida , Monitoramento Ambiental , Hungria , Lagos/química , Espectrometria de Massas em Tandem
4.
J Agric Food Chem ; 63(26): 6059-65, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-26057604

RESUMO

From an extract of red mamey (Pouteria sapota) ß-cryptoxanthin-5,6-epoxide, ß-cryptoxanthin-5',6'-epoxide, 3'-deoxycapsanthin, and cryptocapsin were isolated and characterized by UV-vis spectroscopy, electronic circular dichroism (ECD), nuclear magnetic resonance (NMR) spectroscopy, and mass spectrometry (MS). Epoxidation of ß-cryptoxanthin delivered the ß-(5'R,6'S)- and (5'S,6'R)-cryptoxanthin-5',6'-epoxides, which were identified by HPLC-ECD analysis. These carotenoids among others are quite common in the fruits of Central America, and as they are natural provitamins A, they should play an important role in the diet of the mostly vitamin A deficient population of this region.


Assuntos
Capsaicina/química , Carotenoides/química , Criptoxantinas/química , Compostos de Epóxi/química , Extratos Vegetais/química , Pouteria/química , Capsaicina/isolamento & purificação , Carotenoides/isolamento & purificação , Dicroísmo Circular , Criptoxantinas/isolamento & purificação , Compostos de Epóxi/isolamento & purificação , Frutas/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Extratos Vegetais/isolamento & purificação
5.
Eur J Pharmacol ; 748: 61-7, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25528327

RESUMO

Resveratrol is a polyphenol found in grapes and red wine, showing well-characterized anti-inflammatory and antiproliferative activities. In order to exceed resveratrol׳s biological effects and to reveal the structural determinants of the molecule׳s activity, numerous derivatives were synthesized recently. Most of these resveratrol analogs vary from the original molecule in the number, position or identity of the phenolic functional groups. Investigation of the analogs provided important data regarding structure-activity relationship of the molecule. With the exception of cis- and trans-resveratrol and the reduced form dihydroresveratrol, little is known about the molecular effects of the stilbene backbone. In the present study we investigated the anti-inflammatory properties of a new, triple-bond resveratrol analog, 3,4',5-trihydroxy-diphenylacetylene (TDPA) on lipopolysaccharide-stimulated RAW macrophages. We found that the analog had weaker antioxidant activity and stronger inhibitory effect on nuclear factor-kappaB activation, and on cyclooxygenase-2, tumor necrosis factor α and interleukin-6 production. It also prevented lipopolysaccharide-induced depolarization of the mitochondrial membrane. In contrast to resveratrol, TDPA increased the phosphorylation of c-Jun N-terminal and p38 mitogen activated protein kinases. In summary, we identified a novel compound with better anti-inflammatory properties than resveratrol. Our results contributed to a better understanding of the structural determinants of resveratrol׳s biological activities.


Assuntos
Acetileno/análogos & derivados , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Resorcinóis/química , Resorcinóis/farmacologia , Estilbenos/química , Acetileno/química , Acetileno/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocinas/biossíntese , Lipopolissacarídeos/efeitos adversos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , NF-kappa B/metabolismo , Resveratrol , Transdução de Sinais/efeitos dos fármacos , Estilbenos/farmacologia , Relação Estrutura-Atividade
6.
J Pharm Biomed Anal ; 103: 59-66, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25462121

RESUMO

A sensitive and selective reverse-phase high performance liquid chromatographic method with fluorescence detection has been developed for determination of capsaicin (8-methyl-N-vanillyl-(trans)-6-nonenamid) and dihydrocapsaicin (8-methyl-N-vanillylnonanamide) in samples generated in rat small intestine luminal perfusion experiments. The experiments were designed to study the biotransformation of capsaicinoids in the small intestine in the rat. The chromatographic separation was performed at room temperature on a ZORBAX Eclipse(®) XDB-C8 column using isocratic elution with a mobile phase consisting 0.05M orthophosphoric acid solution and acetonitrile (60:40, v/v; pH 3.0) with a flow rate of 1.5mL/min. Fluorescence detection was performed at excitation and emission wavelengths of 230 and 323nm, respectively. The method was evaluated for a number of validation characteristics (accuracy, repeatability and intermediate precision, limit of detection, limit of quantification and calibration range). The limit of detection (LOD) was 50ng/mL and the limit of quantification (LOQ) was 100ng/mL for both capsaicin and dihydrocapsaicin reference standards dissolved in blank perfusate. The method was successfully applied for investigation of intestinal absorption of capsaicin and dihydrocapsaicin while 30µg/mL standardized Capsicum extract - containing capsaicin and dihydrocapsaicin - was luminally perfused for a 90min period. The structure of the glucuronide metabolites of capsaicin and dihydrocapsaicin appeared in the perfusate was identified by mass spectrometry.


Assuntos
Capsaicina/análogos & derivados , Capsaicina/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Absorção Intestinal , Espectrometria de Fluorescência/métodos , Animais , Área Sob a Curva , Calibragem , Capsaicina/metabolismo , Limite de Detecção , Masculino , Ratos , Ratos Wistar , Padrões de Referência , Reprodutibilidade dos Testes
7.
Int J Legal Med ; 127(2): 529-33, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23108457

RESUMO

The fast, high-throughput distinction between paleoanthropological remains and recent forensic/clinical bone samples is of vital importance in the field of medicolegal science. In this paper, a novel screening method has been described, using the crystallinity index (C.I.) and carbonate-phosphate index (C/P) as a means to distinguish between archeological and forensic anthropological skeletal findings. According to the Fourier transform infrared spectroscopy analyses, the archeological bone samples are characterized by a range of C.I. between 2.84 and 3.78 and by low C/P values of 0.10-0.33, while the C.I. and C/P ranges of forensic skeletal remains are 2.55-3.18 and 0.38-0.88, respectively. Significant (p < 0.05) changes were observed in C/P as well as C.I. values between the groups of forensic and archeological skeletal samples. The suggested dating method needs only a few milligramms of bone tissue; thus, it can be extremely useful for distiguishing ancient and recent bone fragments.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Calcificação Fisiológica , Vértebras Torácicas/anatomia & histologia , Adulto , Apatitas/análise , Carbonatos/análise , Cristalização , Feminino , Antropologia Forense , Humanos , Masculino , Fosfatos/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Vértebras Torácicas/química
8.
Mem. Inst. Oswaldo Cruz ; 107(8): 1048-1053, Dec. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-660654

RESUMO

The purpose of this study was to analyse a skeleton (adult female, 25-30 years) that presented evidence of tuberculous spondylitis. The skeleton, dated from the Roman Period (III-VI centuries), was excavated near the town of Győr, in western Hungary. The skeleton was examined by gross observation supplemented with mycolic acid and proteomic analyses using MALDI-TOF/TOF tandem mass spectrometry. The biomolecular analyses supported the morphological diagnosis.


Assuntos
Adulto , Feminino , História Antiga , Humanos , Tuberculose da Coluna Vertebral/história , Hungria , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tuberculose da Coluna Vertebral/patologia
9.
Mem Inst Oswaldo Cruz ; 107(8): 1048-53, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23295757

RESUMO

The purpose of this study was to analyse a skeleton (adult female, 25-30 years) that presented evidence of tuberculous spondylitis. The skeleton, dated from the Roman Period (III-VI centuries), was excavated near the town of Gyor, in western Hungary. The skeleton was examined by gross observation supplemented with mycolic acid and proteomic analyses using MALDI-TOF/TOF tandem mass spectrometry. The biomolecular analyses supported the morphological diagnosis.


Assuntos
Tuberculose da Coluna Vertebral/história , Adulto , Feminino , História Antiga , Humanos , Hungria , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tuberculose da Coluna Vertebral/patologia
10.
J Chromatogr Sci ; 43(9): 445-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16212788

RESUMO

A new, simple procedure for the determination of phenolic components of wines, such as resveratrol and piceid isomers, has been elaborated and validated. A set of 70 red wines and 3 white wines from two wineries (Polgar Winery and Bock Winery, Villany, Hungary) are analyzed by reversed-phase high-performance liquid chromatography. The samples are injected without pretreatment and UV-vis and mass spectrometric (MS) detection has been applied. The detection limit for trans-resveratrol and for trans-piceid is found to be 0.9 and 0.6 pmol for the UV-vis detection method and 0.3 and 0.2 pmol for the MS detection method. Trans-resveratrol and trans-piceid are found in red wines from 0.1 to 14.3 mg/L and from 3.8 to 16.4 mg/L concentrations, respectively.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Glucosídeos/análise , Estilbenos/análise , Vinho/análise , Eletroforese Capilar , Espectrometria de Massas , Reprodutibilidade dos Testes , Resveratrol , Espectrofotometria Ultravioleta
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...