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1.
Toxicol Lett ; 155(2): 319-27, 2005 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-15603927

RESUMO

To determine the genotoxic risk associated to environmental arsenic exposure, the frequency of micronuclei in buccal cells (BCMN) of people drinking arsenic-contaminated water has been evaluated. A group of 105 individuals from the Antofagasta region (north Chile), and 102 individuals from the area of Concepcion, used as reference group, were included in the study. Arsenic concentration in drinking water was high (0.75 mg/L) in the Antofagasta area, 75-fold the maximum recommended level by WHO (0.01 mg/L), while the values obtained in Concepcion were significantly lower (0.002 mg/L). Individual measures of arsenic exposure were also determined in fingernails, which clearly confirm the existence of chronic exposure in the sampled populations from the Antofagasta region (10.15 microg/g versus 3.57 microg/g). The cytogenetic results indicate that, although the BCMN frequency is higher in exposed than in controls, this increase does not attain statistical significance. When the exposure biomarkers were related with the cytogenetic values, no correlations were observed between BCMN and arsenic content in water or in fingernails. In addition, the genotoxicity values do not seem to be related to the ethnic origin from people belonging to the exposed group. As a conclusion it appears that, in the studied population, the chronic ingestion of arsenic-contaminated water does not induce cytogenetic damage, measured as micronuclei, in the cells of the oral mucous in a significant extent.


Assuntos
Arsenicais/efeitos adversos , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Mucosa Bucal/efeitos dos fármacos , Poluentes Químicos da Água/efeitos adversos , Adulto , Chile , Feminino , Humanos , Masculino , Testes para Micronúcleos , Mucosa Bucal/citologia , Unhas/química , Abastecimento de Água/normas
2.
Mutat Res ; 564(1): 65-74, 2004 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-15474412

RESUMO

In the present study we have evaluated whether or not environmental exposure to arsenic in ground drinking-water results in a significant increase in the frequency of micronuclei (MN) in peripheral blood lymphocytes. Thus, 106 individuals from the Antofagasta region (North Chile), together with 111 individuals from the area of Concepción, were used in this investigation. In the Antofagasta area, arsenic levels in drinking-water as high as 0.750 mg/L were measured. In Concepción, located about 2500 km towards the south and used as reference area, arsenic levels in tap water were as low as 0.002 mg/L. The total content of arsenic in fingernails was determined as a biomarker of individual exposure. The cytogenetic results obtained in this study indicate that in the exposed group the overall frequency of binucleated micronucleated cells (BNMN) is higher than in the reference group, the difference being statistically significant. In addition, no differences were found between the exposed and the reference groups, regarding the cytokinesis-block proliferation index (CBPI). No association was observed between BNMN and arsenic content in water or arsenic in fingernails. On the other hand, when the exposed group was divided according to their Atacameno or Caucasian ethnicity, no significant differences were observed between them. In addition, as usually found in other human biomonitoring studies, sex and age are factors that modulate the frequency of MN in both exposed and reference populations.


Assuntos
Intoxicação por Arsênico/epidemiologia , Arsênio/análise , Arsênio/toxicidade , Carcinógenos/análise , Exposição Ambiental , Micronúcleos com Defeito Cromossômico , Adulto , Biomarcadores , Células Cultivadas , Chile , Feminino , Testes Hematológicos , Humanos , Linfócitos/citologia , Linfócitos/fisiologia , Masculino , Testes para Micronúcleos , Unhas/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Poluição Química da Água , Abastecimento de Água
3.
J Ethnopharmacol ; 38(2-3): 153-7, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8510463

RESUMO

A chemical investigation of the bark of Mimosa tenuiflora (Willd.) Poiret, performed in our laboratory, allowed the isolation and identification of three new triterpenoid saponins (mimonosides A, B and C), three steroid saponins (3-O-beta-D-glucopyranosyl campesterol, 3-O-beta-D-glucopyranosyl stigmasterol and 3-O-beta-D-glucopyranosyl beta-sitosterol) together with lupeol, campesterol, stigmasterol and beta-sitosterol. The three new triterpenoid saponins were subjected to in vitro biological tests (immunomodulation and proliferation) using different animal and human cells in culture. The results of these tests contribute to explain the traditional use of this plant material.


Assuntos
Plantas Medicinais/química , Animais , Humanos , México , Farmacognosia
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