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  • 1
    ISSN: 1436-5073
    Keywords: quality ; improvement ; organotins ; environment ; interlaboratory studies ; certified reference materials
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract One of the major prerequisites for the certification of various analytes in different Certified Reference Materials (CRMs) is that the analytical methods used are of verified performance and, hence, that no systematic errors have been left undetected. In the case of difficult measurements, research and feasibility studies are often necessary to ensure that the methods are operating under good quality control. The EC Standards Measurements and Testing Programme (SMT, formerly BCR) usually follows a step-by-step approach which consists in series of interlaboratory studies to assess and improve the quality of measurements prior to certification by comparing different analytical techniques. A programme following such stepwise approach has started in 1987 with the aim of improving the quality of butyltin determinations in environmental matrices. The project involved ca. 20 laboratories from different Member States of the European Union. The first interlaboratory study dealt with simple solutions containing mixtures of organotin compounds and a second exercise focused on the analysis of a tributyltin-spiked sediment. These exercises were continued by two certifications on butyltins in sediment, the first of which could not be successfully concluded owing to the high spread of results observed between the results of different techniques. The second certification allowed a CRM certified for its contents of di- and tributyltin (CRM 462) to be produced. This programme on Sn speciation is now focusing on the certification of butyltin and phenyltin compounds in candidate CRMs of mussel and sediment. This paper gives an account of the step-by-step approach followed and presents the results of the two certification exercises carried out so far. The preparation of the mussel candidate CRM is also described.
    Type of Medium: Electronic Resource
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  • 2
    Publication Date: 2021-05-19
    Description: El D-004 es un extracto lipídico obtenido del fruto de la palma real (Roystonea regia) (Arecaceae) que consiste en una mezcla reproducible de ácidos grasos, en la cual el ácido oleico, el laurico y el palmítico son los más abundantes. El tratamiento oral con D-004 inhibe significativamente la hiperplasia prostática (HP) inducida por testosterona en roedores. El objetivo de este trabajo fue investigar si el D-004 induce mutaciones génicas puntuales en el ensayo de Ames por incorporación directa en placa. Se utilizaron las cepas TA 1535, TA 98 y TA 100 de Salmonella typhimurium. El ensayo se realizó tanto con la adición de la fracción microsomal hepática (S9) como sin ella. Como controles positivos en este ensayo se emplearon dos mutágenos, uno directo: la azida de sodio (AzNa) y uno indirecto: el 2-acetil amino fluoreno (2-AAF). Las concentraciones de D-004 empleadas fueron 5, 50, 500, 2000 y 5000 μg/placa, utilizando el vehículo Tween 65 (0,2 %) como control negativo. Los resultados mostraron que el D-004 no afectó significativamente la frecuencia de reversión respecto al control negativo para ambas variantes del ensayo de Ames, con o sin activación metabólica, en las cepas empleadas. Como era esperado, los controles positivos AzNa y 2-AAF incrementaron significativamente el número de colonias revertantes con respecto al control negativo. Los niveles de frecuencia de reversión espontánea y el número de revertantes obtenidas con los controles positivos en este estudio están en el rango de los valores históricos obtenidos en nuestro laboratorio para cada una de las cepas empleadas. El presente estudio demuestra que el D-004 no presenta potencial mutagénico en el ensayo de Ames por incorporación directa a placa en las cepas estudiadas.
    Description: D-004 is a lipid extract of the fruits of the Cuban royal palm (Roystonea regia) (Arecaceae), which consist in a mixture of fatty acids, in which oleic, lauric and palmitic are the most abundant. Oral treatment with D-004 significantly prevents the prostate hyperplasia (PH) induced with testosterone in rodents. This study was conducted to investigate whether D-004 induces gene mutations in the Ames test for plate incorporation method. The tester strains used were TA 1535, TA 98 y TA 100 of Salmonella typhimurium. The test was done with and without metabolic activation. As positive controls two mutagenic agents, sodium azide (NaAz) and 2-acetyl aminofluorene (2-AAF), were used. The doses of D-004 used were 5, 50, 500, 2000 y 5000 μg/plate, using Tween 65 (0.2 %) vehicle as negative control. D-004 did not change significantly the reversion frequency compare with negative control in the Ames test in both alternatives with or without S9 metabolic activation, in the used strains. As expected, the positive controls, NaAz and 2-AAF significantly increased the frequency of revertants compared with the negative control. The frequencies of spontaneous reversions and the number of revertants observed in this study are within the historical values obtained in our lab for each strain. This study demonstrates that D-004 has not potential mutagenic in the Ames test for plate incorporation.
    Description: Centro de Productos Naturales. Centro Nacional de Investigaciones Científicas
    Description: Published
    Description: Ames test, D-004, Roystonea regia, potential mutagenic
    Keywords: Fatty acids ; Fatty acids
    Repository Name: AquaDocs
    Type: Journal Contribution
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