RESUMEN
The present study proposes the use of endophytic fungi for mercury bioremediation in in vitro and host-associated systems. We examined mercury resistance in 32 strains of endophytic fungi grown in culture medium supplemented with toxic metal concentrations. The residual mercury concentrations were quantified after mycelial growth. Aspergillus sp. A31, Curvularia geniculata P1, Lindgomycetaceae P87, and Westerdykella sp. P71 were selected and further tested for mercury bioremediation and bioaccumulation in vitro, as well as for growth promotion of Aeschynomene fluminensis and Zea mays in the presence or absence of the metal. Aspergillus sp. A31, C. geniculata P1, Lindgomycetaceae P87 and Westerdykella sp. P71 removed up to 100% of mercury from the culture medium in a species-dependent manner and they promoted A. fluminensis and Z. mays growth in substrates containing mercury or not (Dunnett's test, pâ¯<â¯0.05). Lindgomycetaceae P87 and C. geniculata P1 are dark septate endophytic fungi that endophytically colonize root cells of their host plants. The increase of host biomass correlated with the reduction of soil mercury concentration due to the metal bioaccumulation in host tissues and its possible volatilization. The soil mercury concentration was decreased by 7.69% and 57.14% in A. fluminensis plants inoculated with Lindgomycetaceae P87 + Aspergillus sp. A31 and Lindgomycetaceae P87, respectively (Dunnet's test, pâ¯<â¯0.05). The resistance mechanisms of mercury volatilization and bioaccumulation in plant tissues mediated by these endophytic fungi can contribute to bioremediation programs. The biochemical and genetic mechanisms involved in bioaccumulation and volatilization need to be elucidated in the future.
Asunto(s)
Biodegradación Ambiental , Hongos/química , Mercurio/químicaRESUMEN
The endophytic fungal communities of Polygonum acuminatum and Aeschynomene fluminensis were examined with respect to soil mercury (Hg) contamination. Plants were collected in places with and without Hg+2 for isolation and identification of their endophytic root fungi. We evaluated frequency of colonization, number of isolates and richness, indices of diversity and similarity, functional traits (hydrolytic enzymes, siderophores, indoleacetic acid, antibiosis and metal tolerance) and growth promotion of Aeschynomene fluminensis inoculated with endophytic fungi on soil with mercury. The frequency of colonization, structure and community function, as well as the abundant distribution of taxa of endophytic fungi were influenced by mercury contamination, with higher endophytic fungi in hosts in soil with mercury. The presence or absence of mercury in the soil changes the profile of the functional characteristics of the endophytic fungal community. On the other hand, tolerance of lineages to multiple metals is not associated with contamination. A. fluminensis depends on its endophytic fungi, since plants free of endophytic fungi grew less than expected due to mercury toxicity. In contrast plants containing certain endophytic fungi showed good growth in soil containing mercury, even exceeding growth of plants cultivated in soil without mercury. The data obtained confirm the hypothesis that soil contamination by mercury alters community structure of root endophytic fungi in terms of composition, abundance and species richness. The inoculation of A. fluminensis with certain strains of stress tolerant endophytic fungi contribute to colonization and establishment of the host and may be used in processes that aim to improve phytoremediation of soils with toxic concentrations of mercury.
Asunto(s)
Endófitos/efectos de los fármacos , Fabaceae/microbiología , Mercurio/efectos adversos , Polygonum/microbiología , Microbiología del Suelo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/microbiologíaRESUMEN
OBJECTIVE: The Framework Convention on Tobacco Control (FCTC) aims to coordinate tobacco control policies around the world that reduce tobacco consumption. The FCTC's recommended policies are likely to be effective in low- and middle-income countries. Nevertheless, policy evaluation studies are needed to determine policy impact and potential synergies across policies. MATERIAL AND METHODS: The International Tobacco Control Policy Evaluation Project (ITC) is an international collaboration to assess the psychosocial and behavioral impact of the FCTC's policies among adult smokers in nine countries. The ITC evaluation framework utilizes multiple country controls, a longitudinal design, and a theory-driven conceptual model to test hypotheses about the anticipated effects of given policies. RESULTS: ITC Project results generally confirm previous studies that form the evidence base for FCTC policy recommendations, in particular: the use of graphic warning labels; banning of "light" and "mild" descriptors; smoking bans; increasing tax and price; banning advertising; and using new cigarette product testing methods. CONCLUSIONS: Initial findings from the ITC Project suggest that Latin American countries could use similar methods to monitor and evaluate their own tobacco control policies while contributing to the evidence base for policy interventions in other countries.
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Publicidad/legislación & jurisprudencia , Política de Salud , Prevención del Hábito de Fumar , Industria del Tabaco/legislación & jurisprudencia , Adolescente , Adulto , Educación en Salud , Humanos , Cooperación Internacional , América Latina , Salud Pública , Fumar/legislación & jurisprudenciaRESUMEN
OBJECTIVE: To determine which graphic warnings on cigarette packs (images on the labels indicating the negative impact on health that tobacco can have) provoke the strongest desire to quit smoking among adult Mexican smokers. MATERIAL AND METHODS: A pile sort method was used among 60 smokers over 18 years old to determine which images made them think about quitting smoking. Averages were determined and non-parametric statistical methods were used to determine differences in ranks. RESULTS: Within each of the five themes, one or two graphic warnings provoked the strongest responses in smokers. The graphic warnings with the greatest impact used the following images: a close-up of a lung tumor; a man with cancer of the larynx with a large tumorous mass on the exterior part of his neck; an unconscious young man in a bed in an intensive care unit with text mentioning benzene, formaldehyde and cyanide as tobacco components; an image of two healthy children indicating that cigarettes contain carbon monoxide; an image of a dead fetus in a specimen jar; and a close up of a mouth with yellow, rotting teeth and text describing tooth loss and mouth cancer as a result of tobacco use. CONCLUSIONS: The graphic warnings used on cigarette packs in other countries could contribute to cessation among Mexican smokers and should be implemented in Mexico.
Asunto(s)
Etiquetado de Productos , Cese del Hábito de Fumar/métodos , Prevención del Hábito de Fumar , Fumar/efectos adversos , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , México , Persona de Mediana Edad , Estadísticas no ParamétricasRESUMEN
OBJETIVO: Determinar el impacto de los avisos gráficos (imágenes en las etiquetas que indican el daño a la salud que causa el tabaco) en las cajetillas de cigarros entre fumadores adultos mexicanos. MATERIAL Y MÉTODOS: Se aplicó el método antropológico de sorteo de montones a 60 fumadores adultos para determinar cuáles los hacían pensar en dejar de fumar. Se sacaron promedios y se utilizaron métodos estadísticos no paramétricos. RESULTADOS: Los avisos gráficos más impactantes mostraban las siguientes imágenes: un tumor de bronquio fuente visto a través del broncoscopio; un hombre con cáncer de laringe con una gran masa tumoral externa en el cuello; un hombre joven inconsciente en una cama de la unidad de cuidados intensivos, con texto mencionando benceno, formaldehído y cianuro de hidrógeno como componentes del tabaco, y una de dos niños sanos que indica que el cigarro contiene amoníaco, monóxido de carbono; un feto muerto en un frasco con formol; y una boca con dientes amarillos y con texto que menciona la pérdida de dientes y cáncer bucal como resultados del tabaco. CONCLUSIONES: Los avisos gráficos que se utilizan en las cajetillas de cigarros en otros países podrían contribuir a la cesación entre fumadores mexicanos y deben implementarse en México.
Asunto(s)
Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Etiquetado de Productos , Cese del Hábito de Fumar/métodos , Fumar/efectos adversos , Fumar/prevención & control , México , Estadísticas no ParamétricasRESUMEN
OBJETIVO: El Convenio Marco para el Control del Tabaco (CMCT) pretende coordinar las políticas mundiales que reducen el consumo de tabaco. Con toda probabilidad, estas medidas tendrán efectos en países de ingresos medianos y bajos; no obstante, se requieren estudios de evaluación para determinar sus consecuencias y las posibles sinergias entre las directrices. MATERIAL Y MÉTODOS: El Proyecto Internacional de Evaluación de Políticas para el Control del Tabaco (ITC) es una colaboración internacional para evaluar el efecto psicosocial y conductual que causan las políticas promovidas por el CMCT en adultos fumadores de nueve países. El marco de evaluación ITC utiliza diversos controles de país, con un diseño longitudinal y un modelo conceptual basado en teorías para probar las hipótesis sobre los efectos anticipados de determinadas políticas. RESULTADOS: Los resultados del análisis de datos confirman por lo general los hallazgos anteriores de investigaciones basadas en las recomendaciones del CMCT, y se refieren a las siguientes políticas: promover etiquetas de advertencia con imágenes gráficas, prohibir el uso de las descripciones "ligero" y "suave", establecer ambientes libres de humo de tabaco, incrementar los impuestos, prohibir la publicidad del cigarro e implementar nuevos métodos para evaluar los componentes del cigarro. CONCLUSIONES: Los hallazgos iniciales sugieren que los países latinoamericanos podrían aplicar métodos similares para vigilar y evaluar sus propias directrices, así como fortalecer el cuerpo de conocimiento sobre políticas en otros países.