RESUMEN
The beneficial effects of fish consumption in both children and adults are well known. However, the intake of methylmercury, mainly from contaminated fish and shellfish, can have adverse health effects. The study group on the prevention of exposure to methylmercury (GEPREM-Hg), made up of representatives from different Spanish scientific societies, has prepared a consensus document in a question and answer format, containing the group's main conclusions, recommendations and proposals. The objective of the document is to provide broader knowledge of factors associated with methylmercury exposure, its possible effects on health amongst the Spanish population, methods of analysis, interpretation of the results and economic costs, and to then set recommendations for fish and shellfish consumption. The group sees the merit of all initiatives aimed at reducing or prohibiting the use of mercury as well as the need to be aware of the results of contaminant analyses performed on fish and shellfish marketed in Spain. In addition, the group believes that biomonitoring systems should be set up in order to follow the evolution of methylmercury exposure in children and adults and perform studies designed to learn more about the possible health effects of concentrations found in the Spanish population, taking into account the lifestyle, eating patterns and the Mediterranean diet.
Asunto(s)
Consenso , Exposición a Riesgos Ambientales/análisis , Compuestos de Metilmercurio/efectos adversos , Animales , Dieta , Peces , Embalaje de Alimentos , Humanos , EspañaRESUMEN
Mercury is an environmental toxicant that causes numerous adverse effects on human health and natural ecosystems. The factors that determine the existance of adverse effects, as well as their severity are, among others: the chemical form of mercury (elemental, inorganic, organic), dosis, age, period of exposure, pathways of exposure and environmental, nutritional and genetic factors. In the aquatic cycle of mercury, once it has been deposited, it is transformed into methylmercury due to the action of certain sulphate-reducing bacteria, which bioaccumulates in the aquatic organisms and moves into the food chain. The methylmercury content of large, long-lived fish such as swordfish, shark, tuna or marlin, is higher. Methylmercury binds to protein in fish and is therefore not eliminated by cleaning or cooking the fish. Fetuses and small children are more vulnerable to the neurotoxic effects of methylmercury from the consumption of contaminated fish. Methylmercury is absorbed in the gastrointestinal tract and crosses the blood-brain barrier and the placenta. The intake of certain dietary components such as polyunsaturated fatty acids, selenium, fiber, thiol compounds, certain phytochemicals and other nutrients can modify methylmercury bioaccesibility and its toxicity. Apart from environmental factors, genetic factors can influence mercury toxicity and explain part of the individual vulnerability.
El mercurio es un tóxico ambiental que causa numerosos efectos adversos en la salud humana y en los ecosistemas naturales. Los factores que determinan la aparición de efectos adversos y su severidad son entre otros: la forma química del mercurio (elemental, inorgánico, orgánico), la dosis, la edad, la duración de la exposición, la vía de exposición y los factores ambientales, nutricionales y genéticos. En el ciclo acuático del mercurio, una vez que se ha depositado, se transforma en metilmercurio por la acción de determinadas bacterias sulfato reductoras y se bioacumula en los organismos acuáticos incorporándose a la cadena trófica de alimentos. El contenido de metilmercurio es mayor en las especies depredadoras de mayor tamaño y que viven más años como el emperador, pez espada, tiburón, atún o marlín. El metilmercurio se halla unido a las proteínas del pescado por lo que no se elimina mediante la limpieza ni el cocinado del mismo. El feto en desarrollo y los niños pequeños son los más vulnerables a los efectos neurotóxicos del metilmercurio procedente de la ingesta de pescado contaminado. El metilmercurio se absorbe en el tracto gastrointestinal y atraviesa la barrera hematoencefálica y la placenta. Algunos componentes de la dieta como los ácidos grasos poliinsaturados, el selenio, la fibra, los compuestos tiol, algunos fitoquímicos y otros nutrientes pueden modificar la bioaccesibilidad del mercurio y su toxicidad. Además de los factores ambientales, los factores genéticos pueden influir en la toxicidad del mercurio y explicar parte de la vulnerabilidad individual.
Asunto(s)
Intoxicación por Mercurio/genética , Intoxicación por Mercurio/patología , Compuestos de Metilmercurio/farmacocinética , Compuestos de Metilmercurio/toxicidad , Estado Nutricional , Envejecimiento , Animales , Femenino , Peces , Humanos , Masculino , Mercurio/metabolismo , Mercurio/farmacocinética , Alimentos Marinos , Caracteres Sexuales , ToxicocinéticaRESUMEN
The benefit of fish consumption in children and adults is well-known. However, it has been pointed out that excessive methylmercury intake due to consumption of contaminated fish leads to neurological toxicity in children, affecting cognitive function, memory, visual-motor function and language. After the intoxications in Minamata and Iraq, wide-ranging epidemiological studies were carried out in New Zealand, the Faroe Islands and the Seychelles and international recommendations were established for fish consumption in pregnant women and small children. In Spain, the Childhood and Environmental project (INMA, its Spanish acronym) has studied the effects of diet and the environment on fetal and childhood development in different geographic areas of Spain. National and international sudies have demonstrated that mercury concentrations are mainly dependent on fish consumption, although there are variations among countries which can be explained not only by the levels of fish consumption, but also by the type or species of fish that is consumed, as well as other factors. Although the best documented adverse effects of methylmercury are the effects on nervous sytem development in fetuses and newborns, an increasing number of studies indicate that cognitive function, reproduction and, especially, cardiovascular risk in the adult population can also be affected. However, more studies are necessary in order to confirm this and establish the existance of a causal relationship.
Los efectos beneficiosos del consumo de pescado tanto en niños como en adultos han sido bien reconocidos. Sin embargo, se ha referido que la ingesta excesiva de metilmercurio procedente del pescado contaminado produce toxicidad neurológica en los niños afectando a la función cognitiva, la memoria, la función visual-motora y al lenguaje. Después de las intoxicaciones de Minamata e Iraq, se realizaron grandes estudios epidemiológicos en Nueva Zelanda, las islas Féroe y las islas Seychelles y se establecieron recomendaciones internacionales sobre el consumo de pescado y marisco en las mujeres embarazadas y niños pequeños. En España, el proyecto Infancia y Medio Ambiente (INMA) ha estudiado los efectos del medio ambiente y de la dieta sobre el desarrollo fetal e infantil en diversas zonas geográficas de España. Los estudios realizados nacionales e internacionales muestran que la concentración de mercurio depende principalmente del consumo de pescado, aunque existe una variabilidad entre los países que podría explicarse no solo por la cantidad de pescado consumida, sino también por el tipo o especies de pescados que se consumen, así como por otro tipo de factores. Aunque los efectos perjudiciales del metilmercurio mejor documentados son los que se producen sobre el desarrollo del sistema nervioso en el feto y en el recién nacido, cada vez hay más estudios que indican que también puede afectar a la función cognitiva, reproducción y especialmente al riesgo cardiovascular en la población adulta. Sin embargo, son necesarios más estudios para confirmarlo y establecer la existencia de una relación causal.
Asunto(s)
Peces , Intoxicación por Mercurio/epidemiología , Compuestos de Metilmercurio/toxicidad , Alimentos Marinos/efectos adversos , Adulto , Animales , Femenino , Humanos , Lactante , Recién Nacido , Intoxicación por Mercurio/etiología , Compuestos de Metilmercurio/envenenamiento , Embarazo , Alimentos Marinos/análisisRESUMEN
The beneficial effects of fish consumption are well- known. Nevertheless, there is worldwide concern regard methylmercury concentrations in fish, which is why many countries such as the United States, Australia, New Zealand, Canada and numerous European countries have made fish consumption recommendations for their populations, particularly vulnerable groups, in order to México methylmercury intake. Blood and hair are the best biological samples for measuring methylmercury. The most widely-used method to analyse methylmercury is cold vapor atomic absorption spectrometry, although there are also direct methods based on the thermal decomposition of the sample. In recent years, the number of laboratories that measure mercury by inductively coupled plasma mass spectrometry has increased. In addition, the different kinds of mercury can be distinguished by coupling chromatography methods of separation. Laboratories that analyse mercury in biological samples need to participate in external quality control programmes. Even if mercury emissions are reduced, mercury may remain in the environment for many years, so dietary recommendations are fundamental in order to reduce exposure. It is necessary to propose public health measures aimed at decreasing mercury exposure and to evaluate the benefits of such measures from the economic and social standpoints.
Los efectos beneficiosos del consumo de pescado son bien reconocidos. Sin embargo, existe preocupación a nivel mundial sobre los niveles de metilmercurio en el pescado, por lo que muchos países como Estados Unidos, Australia, Nueza Zelanda, Canadá y muchos países europeos han realizado recomendaciones de consumo de pescado a la población , especialmente a los grupos vulnerables con el fin de reducir la ingesta de metilmercurio. La sangre y el pelo son las mejores muestras biológicas para medir el metilmercurio. El método de análisis más empleado ha sido la espectroscopia de absorción atómica con la técnica del vapor frío, aunque existen también métodos directos que se basan en la descomposición térmica de la muestra. En los últimos años han aumentado los laboratorios que miden el mercurio por espectrometría de masas con plasma acoplado por inducción. Además, se puede diferenciar las distintas especies de mercurio acoplando métodos de separación cromatográficos. Es necesario que los laboratorios que analizan mercurio en muestras biológicas participen en programas de garantía externa de la calidad. Aunque se logre reducir las emisiones de mercurio, el mercurio del medio ambiente todavía puede permanecer muchos años, por lo que es fundamental el consejo dietético para disminuir la exposición. No es aconsejable el uso de terapia quelante con fines diagnósticos o en pacientes asintomáticos. Es preciso proponer medidas de salud pública encaminadas a la disminución de la exposición al mercurio y que se evalúe también los beneficios de las mismas desde el punto de vista económico y social.
Asunto(s)
Compuestos de Metilmercurio/análisis , Compuestos de Metilmercurio/toxicidad , Animales , Análisis Costo-Beneficio , Peces , Contaminación de Alimentos/análisis , Contaminación de Alimentos/economía , Humanos , Compuestos de Metilmercurio/economíaRESUMEN
The beneficial effects of fish consumption in both children and adults are well known. However, the intake of methylmercury, mainly from contaminated fish and shellfish, can have adverse health effects. The study group on the prevention of exposure to methylmercury (GEPREM-Hg), made up of representatives from different Spanish scientific societies, has prepared a consensus document in a question and answer format, containing the group's main conclusions, recommendations and proposals. The objective of the document is to provide broader knowledge of factors associated with methylmercury exposure, its possible effects on health among the Spanish population, methods of analysis, interpretation of the results and economic costs, and to then set recommendations for fish and shellfish consumption. The group sees the merit of all initiatives aimed at reducing or prohibiting the use of mercury as well as the need to be aware of the results of contaminant analyses performed on fish and shellfish marketed in Spain. In addition, the group believes that biomonitoring systems should be set up in order to follow the evolution of methylmercury exposure in children and adults and perform studies designed to learn more about the possible health effects of concentrations found in the Spanish population, ta king into account the lifestyle, eating patterns and the Mediterranean diet.
Los efectos beneficiosos del consumo de pescado tanto en niños como en adultos han sido bien reconocidos. Sin embargo, la ingesta de metilmercurio principalmente a través del pescado y marisco contaminado puede producir efectos adversos en la salud. El grupo de estudio para la prevención de la exposición al metilmercurio (GEPREM-Hg), constituido por representantes de diferentes sociedades científicas españolas, ha elaborado un documento de consenso donde se recogen en forma de preguntas y respuestas las principales conclusiones, recomendaciones y propuestas planteadas en el grupo. El objetivo del documento es profundizar en el conocimiento de los factores asociados a la exposición al metilmercurio, los posibles efectos sobre la salud en la población española, los métodos de análisis, la interpretación de los resultados, el coste económico y establecer finalmente recomendaciones de consumo de pescados y mariscos. El grupo considera acertadas todas las iniciativas encaminadas a reducir o prohibir el uso del mercurio y la necesidad de conocer los resultados de los análisis de contaminantes que se realizan en los pescados y mariscos que se comercializan en España. Además, opina que se deberían establecer sistemas de biomonitorización para conocer la evolución de la exposición al metilmercurio en niños y adultos y realizar estudios diseñados para conocer los posibles efectos sobre la salud de las concentraciones halladas en la población española, teniendo en cuenta el estilo de vida, los patrones de consumo alimentarios y la dieta mediterránea.
Asunto(s)
Compuestos de Metilmercurio/efectos adversos , Compuestos de Metilmercurio/análisis , Alimentos Marinos/efectos adversos , Alimentos Marinos/análisis , Adulto , Niño , Consenso , Dieta Mediterránea , Contaminación de Alimentos/análisis , Humanos , España/epidemiologíaRESUMEN
OBJECTIVES: The analysis of urinary stones is used for the diagnosis of the etiology of an episode of nephrolithiasis. The technique considered as standard for this purpose is infrared spectroscopy (IR). However, when the urinary stone is formed by a mixture of components, only semi-quantitative information can be achieved using IR. The objective of this work is the development of a quantitative method. DESIGN AND METHODS: Bands in the IR spectra of several mixtures were studied, in order to design a calibration model useful to determine the quantitative composition of the urinary stones. For mixtures of two components, four mathematical models were proposed. To assess the validity of these models, nine series of mixtures of two components were prepared, using the most frequently compounds found in urinary stones, for analyzing by ATR-FTIR spectroscopy (Attenuated Total Reflection Fourier Transformed Infrared). RESULTS: Nine series of nine mixtures of two components were prepared for this work. The IR spectrum was recorded for each mixture and the absorbance intensities at selected wave numbers were used to apply the proposed mathematical models. There were good linear correlations between the analytical signals (IR absorbances) and the analytical responses (weight fractions) using the calibration lines. The validity of the method was checked by the comparison between the weight fractions resulted from the calibration lines and the real weight fractions obtained by weighing, presenting good correlation parameters. CONCLUSIONS: The method developed in this work has been useful for the quantification of compounds which are commonly found in urinary stones. This method allows a total characterization of the urinary stones (qualitative and quantitative) by means of IR spectroscopy.
Asunto(s)
Espectroscopía Infrarroja por Transformada de Fourier/métodos , Cálculos Urinarios/química , Apatitas/química , Oxalato de Calcio/química , Fosfatos de Calcio/química , Calibración , Modelos Lineales , Modelos Teóricos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Ácido Úrico/químicaRESUMEN
Anthracyclines are frequently used for the treatment of breast cancer and topoisomerase II alpha (TOP2A) is considered to be the molecular target. Numerous studies have evaluated the predictive value of TOP2A using different methodological approaches and inconsistent results have been reported. Indeed, the correlation between techniques for the assessment of TOP2A status has not been well evaluated. In this study, we determined TOP2A status in 61 breast tumor samples by real-time PCR, DNA microarrays, immunohistochemistry (IHC), and fluorescence in situ hybridization (FISH), and then evaluated these results with clinical-pathological features and breast cancer intrinsic subtypes. First, we observed a statistical significant correlation of TOP2A gene expression between real-time PCR and microarrays (Pearson coefficient, 0.816; P < 0.001), and both predicted TOP2A IHC results fairly well (area under the curve > 0.74). In contrast, poor agreement between FISH and IHC data was observed (k: 0.134). Secondly, TOP2A expression was found significantly associated with cell proliferation, and with the highly proliferative Luminal B, Her2-enriched and Basal-like intrinsic subtypes. In conclusion, TOP2A expression in breast cancer was associated with high proliferation and aggressive tumor subtypes and appears to be independent of its amplification status. All of these features should be taken into consideration when assessing the predictive value of TOP2A for anthracycline-based chemotherapy.
