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No disponible
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Humanos , Enterobacteriaceae/aislamiento & purificación , beta-Lactamasas/aislamiento & purificación , Enfermedades Gastrointestinales/microbiologíaRESUMEN
No disponible
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Quinolonas/farmacocinética , Resistencia a Medicamentos/inmunología , Pruebas de Sensibilidad Microbiana/métodos , Farmacorresistencia MicrobianaRESUMEN
The (geno)toxicity of sediment dichloromethane extracts and fractions obtained by size exclusion chromatography were evaluated to investigate effects based on size fractionation. In this study, three sediments were selected according to their incremental contamination in PAHs and in PCBs: Hamilton harbour, Toronto bay and lake St. Clair sediments. Heavy metals, total sulfur and elemental sulfur (S8) were also determined in the (un)fractionated sediment extracts. The liver cells were exposed to concentrations of sediment extracts and fractionated samples for 24 h at 15 degrees C, afterwhich cell viability, cytochrome P4501A1 activity, available free Zn, DNA damage and oxidative stress were determined. The results showed that the sediment extracts contained high levels of sulfur most of which was found in the low molecular weight (LMW) region, i.e., the 2000-50 atomic mass unit (amu) fraction. Elemental sulfur (S8) accounted for 14-41% of extractable sulfur and were found to elute in the post-column volume (PCV) fraction despite its molecular weight of 256 amu. Heavy metals were found mainly in the HMW (i.e. the > 2000 amu) fraction and LMW fractions and very few or none were observed in the PCV fractions. In sediment extracts, sublethal effects were present principally by the HMW and LMW fractions suggesting that some chemicals were also associated with high molecular weight compounds of extractable organic matter. Less toxicity or effect was sometimes found in the extract indicating an antagonistic effect of the contaminants. We found that cell viability and genotoxicity evaluations could be performed on the unfractionated extracts while EROD, available Zn and oxidative stress measurements should be performed on the LMW fractions because of possible antagonist or shielding effects. Considering the cytotoxic responses, the best toxicity ranking in respect to contaminant levels in sediment extract was obtained with the LMW and PCV fractions which accounted for most of the toxic responses in the chromatographic fractions. Moreover, the shielding effect could be explained, in part, by the association of LMW contaminants to large macromolecules.
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Hidrocarburos Aromáticos/toxicidad , Oncorhynchus mykiss , Bifenilos Policlorados/toxicidad , Compuestos Policíclicos/toxicidad , Contaminantes del Suelo/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Hígado/citología , Hígado/efectos de los fármacos , Peso Molecular , Pruebas de Mutagenicidad/métodosAsunto(s)
Antagonistas de Estrógenos/toxicidad , Estrógenos/toxicidad , Hígado/efectos de los fármacos , Oncorhynchus mykiss/metabolismo , Contaminantes del Suelo/toxicidad , Vitelogeninas/análisis , Contaminantes Químicos del Agua/toxicidad , Animales , Benzo(a)pireno/química , Benzo(a)pireno/toxicidad , Citocromo P-450 CYP1A1/metabolismo , Estradiol/química , Estradiol/toxicidad , Antagonistas de Estrógenos/química , Estrógenos/química , Agua Dulce/química , Sedimentos Geológicos/química , Residuos Industriales , Hígado/química , Hígado/enzimología , Hígado/metabolismo , Compuestos Organofosforados/metabolismo , Hidrocarburos Policíclicos Aromáticos/toxicidad , Lluvia , Nieve , Vitelogeninas/biosíntesis , Vitelogeninas/genéticaRESUMEN
BACKGROUND: Lung cancer is the leading cause of death from cancer. Tobacco is related to the development of this type of tumor due to genetic alterations and to the secretion of certain biological markers. Bronchogenic carcinomas secrete a series of biological substances known as tumor markers. Some of these markers, such as carcinoembryonic antigen, neuron-specific enolase, tissue polypeptide antigen (TPA), tissue polypeptide-specific antigen (TPS) and CYFRA 21.1, possess clear clinical value when analyzed in bronchoalveolar lavage (BAL) of patients with lung malignancies, particularly when they are analyzed in the two BAL fractions, bronchial (BF) and alveolar (AF), being more increased in the BF. For this reason, we intend to demonstrate that smokers with cancer secrete more biological substances in the BF and that the concentrations of these markers are higher in the BAL of smokers than in that of non-smokers. METHODS: The five aforementioned tumor markers were studied in the two BAL fractions of 52 lung cancer patients (46 smokers and 6 non-smokers). We performed BAL using 150 ml of 0.9% saline solution divided in three aliquots of 50 ml. The fluid obtained from the first 50 ml was the BF. The liquid from the other two aliquots was the AF. The five tumor marker concentrations were calculated in accord with the indications of the laboratory. RESULTS: The TPA and TPS levels in the BAL of lung cancer patients were more increased in the BF than in the AF, even when the patients were divided into smokers and non-smokers. When we compared smokers with non-smokers, the smokers had higher levels of TPS in the BF and of TPA in the AF. CONCLUSIONS: Thus, we believe that the cellular alterations produced by tobacco are responsible for the secretion of these tumor markers.
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Biomarcadores de Tumor/análisis , Líquido del Lavado Bronquioalveolar/química , Neoplasias Pulmonares/química , Fumar/metabolismo , Anciano , Antígenos de Neoplasias/análisis , Bronquios/química , Antígeno Carcinoembrionario/análisis , Femenino , Humanos , Queratina-19 , Queratinas , Neoplasias Pulmonares/etiología , Masculino , Persona de Mediana Edad , Fosfopiruvato Hidratasa/análisis , Alveolos Pulmonares/química , Fumar/efectos adversos , Antígeno Polipéptido de Tejido/análisisRESUMEN
The use of Hydra attenuata in acute toxicity assessment is a potentially useful tool in (waste) water biomonitoring. The purpose of this study was to compare the sensitivity of H. attenuata with the extensively used Microtox test on 14 (waste) water samples from the Kraków region (South Poland). To this end, specific morphological changes displayed by the freshwater cnidarian Hydra attenuata (lethal LC50s and sublethal EC50s effects) and bioluminescence of the marine bacteria Vibrio fisheri (Microtox) were compared. Clearly, the Hydra assay was the more sensitive indicator of toxicity. No relationship was found among Hydra toxicological responses and water levels of As, Cd, Co, Cu, Pb and Zn. However, it appeared that toxicity to Hydra might be due to ammonia levels. Additional studies to better circumscribe the tolerance of H. attenuata to 'natural' water characteristics are needed.