Modulation of laccase transcriptome during biodegradation of naphthalene by white rot fungus Pleurotus ostreatus

Biodegradation of polycyclic aromatic hydrocarbons (PAHs) using Pleurotus ostreatus was investigated in the current study along with the expression levels of laccase genes involved in biodegradation under variable conditions. Biodegradation of PAHs (naphthalene, anthracene, and 1,10-phenanthroline) was detected spectrophotometrically. Recorded data revealed that biodegradation of the tested PAHs was time dependent. Elevated level of naphthalene biodegradation (86.47%) was observed compared to anthracene (27.87%) and 1,10-phenanthroline (24.51%) within 3 days post incubation. Naphthalene was completely degraded within 5 days. Further incubation enhanced the biodegradation of both anthracene and 1,10-phenanthroline until reaches 93.69% and 92.00% biodegradation of the initial concentration within an incubation period of 11 and 14 days, respectively. Naphthalene was selected as a PAH model. HPLC and thin layer chromatography of naphthalene biodegradation products at time intervals proposed that naphthalene was first degraded to alpha- and ß-naphthol which was further metabolized to salicylic and benzoic acid. The metabolic pathway of naphthalene degradation by this fungus was elucidated based on the detected metabolites. The expression profile of six laccase isomers was evaluated using real-time PCR. The transcriptome of the fungal laccase isomers recorded higher levels of transcription under optimized fermentation conditions especially in presence of both naphthalene and Tween 80. The accumulation of such useful metabolites from the biodegradation of PAH pollutants recommended white rot fungus as a potential candidate for production of platform chemicals from PAH wastes

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Degradative properties of two newly isolated strains of the ascomycetes Fusarium oxysporum and Lecanicillium aphanocladii

Two ascomycete strains were isolated from creosote-contaminated railway sleeper wood. By using a polyphasic approach combining morpho-physiological observations of colonies with molecular tools, the strains were identified as Fusarium oxysporum Schltdl. (IBPPM 543, MUT 4558; GenBank accession no. MG593980) and Lecanicillium aphanocladii Zare & W. Gams (IBPPM 542, MUT 242; GenBank accession no. MG593981). Both strains degraded hazardous pollutants, including polycyclic aromatic hydrocarbons, anthraquinone-type dyes, and oil. Oil was better degraded by F. oxysporum, but the aromatic compounds were better degraded by L. aphanocladii. With both strains, the degradation products of anthracene, phenanthrene, and fluorene were 9,10-anthraquinone, 9,10-phenanthrenequinone, and 9-fluorenone, respectively. During pollutant degradation, F. oxysporum and L. aphanocladii produced an emulsifying compound(s). Both fungi produced extracellular Mn-peroxidases, enzymes possibly involved in the fungal degradation of the pollutants. This is the first report on the ability of L. aphanocladii to degrade four-ring PAHs, anthraquinone-type dyes, and oil, with the simultaneous production of an extracellular Mn-peroxidase

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Prenatal and postnatal exposure to polycyclic aromatic hydrocarbons and allergy symptoms in city children

BACKGROUND: Studies indicate that exposure to polycyclic aromatic hydrocarbons (PAH) is associated with adverse respiratory and allergy outcomes. Exposure to PAH may impair the immune function of the foetus and, subsequently, be responsible for an increased susceptibility of children to allergic diseases. OBJECTIVES: The aim of the present study was to assess the association between mother's exposure to PAH during pregnancy and allergy diseases in their infants. We also assessed the above associations using measured PAH exposure in children's urine during the first two years of life. METHODS: The current analysis was restricted to 455 mothers and their children from Lodz district. The women were interviewed three times during the pregnancy in order to collect demographic, socio-economic and medical history data. Children's health status was assessed at the age of 10-18 months and repeated at two years of age. The associations between dependent dichotomous variables and urine concentrations of 1-hydroxypyrene (1-HP) were analysed using logistic regression. RESULTS: We showed that higher urine concentrations of 1-HP in mothers at 20-24 weeks of pregnancy increased the risk of more frequent respiratory infections (p = 0.02) in children during their first year of life. Higher 1-HP concentrations in children's urine increased the risk of food allergy (p = 0.002) in children during their first two years of life. CONCLUSIONS: This study suggests awareness of environmental factors, which may affect children's health since PAH showed to be a risk factor for airway infections and food allergy in children after adjustment for other risk factors

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Evidencia de la asociación entre cáncer colorrectal y la ingesta de carnes procesadas / Evidence of the association between colorectal cancer and intake of processed meats

Contexto: En 2012 el cáncer colorrectal (CCR) fue el más frecuente tanto en hombres como para mujeres, ocupando el segundo lugar para las mujeres y el tercero para los hombres. Varios mecanismos han sido propuestos para establecer asociaciones entre el consumo de carne roja y procesada y el riesgo de desarrollar CCR. Objetivo: Resumir y evaluar la evidencia disponible sobre la asociación entre el consumo de carne roja y procesada, con el riesgo de desarrollar CCR. Método: Se llevó a cabo una revisión sistemática, realizando una búsqueda en las bases de datos de Pubmed y Scopus, e identificando los artículos relevantes desde 2010 hasta 2015. Resultados: Se incluyeron 19 artículos que respondieron a nuestro objetivo, de los cuales, sólo 8 de mostraron haber encontrado una asociación positiva entre el consumo de carne roja y procesada con el CCR, pero cada uno lo relacionó con un sitio anatómico diferente. Los métodos de cocción y el grado y tiempo de cocinado, concluyeron con resultados contrapuestos, no pudiendo establecerse ninguna asociación clara, solo hubo asociación positiva para la conservación de la carne en escabeche y una asociación negativa para el cocinado al horno. La asociación para los compuestos mutágenos, aminas heterocíclicas (AHCs) y sus biomarcadores, hidrocarburos aromáticos policíclicos (HAPs) y los compuestos N-nitrosos (CONs) sí parecieron contribuir a un mayor riesgo de CCR. Los subtipos de carne roja y procesada fueron clasificados por cada estudio de forma diferente. Factores de confusión como consumo de fibra dietética, frutas y verduras, alcohol, tabaco o patrón de actividad física influyeron en los resultados. Conclusiones: No se dispone de suficiente evidencia científica para apoyar una clara e inequívoca asociación positiva entre el consumo de carne roja y procesada con el riesgo de desarrollar CCR (AU)

Background: In 2012, colorectal cancer (CRC) was the most common in both men and women, ranking second for women and third for men. Several mechanisms have been proposed to establish association between consumption of red and processed meat with the risk of develop CRC. Objective: Summarize and evaluate the available evidence on the association between consumption of red meat and processed meat, with the risk of developing CRC. Methods: A systematic review was performed, by searching in PubMed and Scopus’ databases, and identifying relevant articles from 2010 to 2015. Conclusions: 19 items that responded to our goal, were included. Only 8 of them showed to have found a positive association between the consumption of red and processed meat and CCR, but each associated were with a different anatomic site. Cooking methods, doneness level and cooking time, ended with mixed results, clear association can’ t be established, there were only positive association for the conservation of pickled meat and a negative association for cooking in the oven. The association for mutagenic compounds, heterocyclic amines (HCAs) and biomarkers, polycyclic aromatic hydrocarbons (PAHs) and N-nitroso compounds (NOCs) did appear contribute to an increased risk of CRC. Subtypes of red and processed meat were classified by each study differently. Confounding factors such as consumption of dietary fiber, fruits and vegetables, alcohol, smoke or physical activity pattern influenced the results (AU)

Haloalkalitolerant Actinobacteria with capacity for anthracene degradation isolated from soils close to areas with oil activity in the State of Veracruz, Mexico

The use of native strains of microorganisms from soils is an excellent option for bioremediation. To our knowledge, until now there has been no other group working on the isolation of Actinobacteria from contaminated soils in Mexico. In this study, samples of soils close to areas with oil activity in the State of Veracruz, Mexico, were inoculated for the isolation of Actinobacteria. The strains isolated were characterized morphologically, and the concentrations of NaCl and pH were determined for optimal growth. Strain selection was performed by the detection of a phylogenetic marker for Actinobacteria located at the 23S rRNA gene, followed by species identification by sequencing the 16S rRNA gene. Several haloalkalitolerant Actinobacteria were isolated and identified as: Kocuria rosea, K. palustris, Microbacterium testaceum, Nocardia farcinica and Cellulomonas denverensis. Except for C. denverensis, the biomass of all strains increased in the presence of anthracene. The strains capacity to metabolize anthracene (at 48 h), determined by fluorescence emission, was in the range of 46-54%. During this time, dihydroxy aromatic compounds formed, characterized by attenuated total reflectance Fourier transform infrared spectroscopy bands of 1205 cm-1 and 1217 cm-1. Those Actinobacteria are potentially useful for the bioremediation of saline and alkaline environments contaminated with polycyclic aromatic hydrocarbon compounds (AU)

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Contaminantes orgánicos persistentes en plasma de tortugas bobas (Caretta caretta) varadas en las Islas Canarias / Plasma leves of persistent organic pollutans in loggerhead sea turtles (caretta caretta) stranded in the Canary Islands

En el presente estudio se ha evaluado el grado de contaminación por contaminantes orgánicos persistentes (COPs) en 193 ejemplares de tortuga boba (Caretta caretta) varadas en las Islas Canarias entre 2007-2011. La cuantificación en plasma de los niveles de pesticidas organoclorados (POCs), bifenilos policlorados (PCBs) e hidrocarburos aromáticos policíclicos (PAHs) se realizó mediante GC-MS. Todas las muestras analizadas presentaron niveles cuantificables de alguno de los COPs incluidos en el estudio. El grupo de COPs que presentó mayores niveles fue el de los PAHs (alcanzando la carga total de PAHs 6,45 ng/ml), siendo el fenantreno el hidrocarburo más frecuentemente detectado y a concentraciones más altas, lo que indica el origen petrogénico de estos contaminantes. La contaminación por PCBs alcanzó niveles menores (3,84 ng/ml), predominando el grupo de los hexaclorobifenilos (PCB-153 y PCB- 138 principalmente). Los niveles de contaminación por POCs fueron también bajos alcanzando valores de 1,67 ng/ml, siendo el principal metabolito del DDT, el p,p´-DDE el compuesto más frecuentemente detectado (89,6%) y a más altas concentraciones (0,68 ng/ml). Fue evidente una asociación inversa entre el tamaño de las tortugas y la carga de PCBs y PAHs. Asimismo existieron niveles más altos de contaminación por COPs en los años 2009 y 2010. Este trabajo evalúa por vez primera la presencia de PAHs en sangre de tortugas varadas y nuestros resultados parecen indicar que esta metodología y esta especie animal pueden ser muy útiles para monitorizar la presencia de contaminación por derivados del petróleo en el medio acuático (AU)

This study assessed the degree of contamination by persistent organic pollutants (POPs) present in 193 specimens of loggerhead turtle (Caretta caretta) stranded in the Canary Islands between 2007-2011. Quantification of plasma levels of organochlorine pesticides (POCs), polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) were performed by GC-MS. All samples tested showed measurable levels of several of the POPs included in the study. PAHs was the group that showed the highest levels (total burden of PAHs = 6.45 ng/ml), being phenanthrene the compound most frequently detected and at higher concentrations, indicating the petrogenic origin of these contaminants. PCBs contamination reached lower levels (3.84 ng/ml), dominating the group of hexachlorobiphenyls (PCB-153 and PCB-138 in particular). The pollution levels were also low in the subgroup of POCs, reaching values of 1.67 ng/ml, and being the main metabolite of DDT, p, p'-DDE the compound most frequently detected (89.6%) and at highest concentrations (0.68 ng/ml). There was a clear inverse association between the size of the turtles and the burden of PCBs and PAHs. There were also higher levels of POPs in 2009 and 2010 than in the other years. This study evaluates for the first time the presence of PAHs in stranded turtles blood and our results suggest that this methodology and this animal species can be very useful for monitoring the presence of petroleum derivatives contamination in the aquatic environment (AU)

Estudio comparativo de la aplicación del hidrocarburo aromático policíclico 7, 12-dimetil-1, 2-benzatraceno (DMBA) sobre la mucosa oral del hámster y del cobaya / A comparative study of the effect of applying polycyclic aromatic hydrocarbon, 7,12-dimethyl-1,2-benzanthracene (DMBA), to the oral mucosa of hamsters and guinea-pigs

Introducción: El carcinoma oral de células escamosases una neoplasia maligna con mal pronóstico y baja tasa desupervivencia, en cuya etiología están fuertemente implicadosel tabaco y el alcohol, entre otros factores. En 1954,Salley describió un modelo experimental de carcinogénesisen la mucosa yugal del hámster mediante la aplicación delagente DMBA. Métodos: Hemos desarrollado dos modelosexperimentales diferenciados, basados en la aplicación delDMBA sobre cobayas y hámster respectivamente. Resultados:En el primer modelo (cobayas) no ocurrió el fenómenode la carcinogénesis con el tiempo y las dosis administradas.Solamente observamos áreas de displasia epitelial,que era más severa en los animales que, además del tratamientocon DMBA, ingerían etanol. En el segundo modelo(hámster), se desarrollaron neoplasias malignas, que eranmás numerosas y con un comportamiento biológico másagresivo cuando se administraba el DMBA combinado conel etanol. Conclusiones: El etanol se ha comportado comoagente promotor de la carcinogénesis(AU)

Introduction: Oral squamous cell carcinoma is a malignantneoplasm with a bad prognosis and low survival rate.Tobacco and alcohol are among the most important causativefactors. In 1954, Salley described an experimental modelof carcinogenesis, applying the agent DMBA to the jugalmucosa of hamsters. Methods: we have developed two differentexperimental models based on the application ofDMBA to guinea pigs and hamsters. Results: No carcinogenesiswas seen in the guinea pigs at the administereddoses of DMBA, only areas of epithelial dysplasia, whichwere more severe in the animals that were also given alcohol.Malignant neoplasias developed in the hamsters andwere more numerous and more aggressive when DMBAwas administered together with ethanol. Conclusions: Inthe present study, ethanol acted as an enhancer of carcinogenesis(AU)

Hidrocarburos Aromáticos Policíclicos (HAPs) en productos de la pesca: revisión / Polycyclic Aromatic Hydrocarbons (PAHs) in fishery products: a review

El interés de los hidrocarburos aromáticos policíclicos (HAPs) como contaminantes alimentarios se debe a que, algunos de ellos, son conocidos cancerígenos humanos, clasificados en el grupo 2 de la Agencia Internacional de Investigación sobre el Cáncer (IARC), además de producir efectos teratógenos y otros efectos agudos (alteraciones digestivas, cefaleas, malestar general, agitación y confusión, irritación de piel y mucosas, etc.). La determinación de los niveles de estas sustancias en los alimentos, especialmente en productos de la pesca y en alimentos ahumados, se ha incrementado en los últimos años por diversas causas. Esta revisión reúne los datos más relevantes sobre las concentraciones de estos compuestos en los productos de la pesca así como los valores de ingesta alimentaria estimados para algunas poblaciones

The great interest of the polycyclic aromatic hydrocarbons (PAHs) as food contaminants is due to their well known human carcinogenic properties. Moreover, they are classified in the second group of the International Agency for Research on Cancer (IARC). These compounds also present teratogenic and acute toxic effects (digestive alterations, cephalea, malaise, cluttering, skin and mucosa irritation, etc.). The determination of the levels of these compounds in foods, especially in fishery products and smoked foods, has increased in the last years. This review gathers the most relevant data about the PAHs concentrations in fishery products at the same time that gives information about the estimated dietary intakes of PAHs for certain populations

Coeficientes de partición de hidrocarburos aromáticos policíclicos con sustancias húmicas: un método simple para su determinación / Binding coefficients of polycyclic aromatic hydrocarbons to humic substances: a simple method for their determination

Las sustancias húmicas son componentes importantes de las aguas naturales, son polímeros ácidos, predominantemente aromáticos, que no resultan nocivos a los seres vivos. Sin embargo, su rol en el medio ambiente es importante porque afectan a la biodisponibilidad y toxicidad de muchos compuestos en el ambiente acuático. Por otra parte, entre los contaminantes de los sistemas acuáticos, se hallan los hidrocarburos aromáticos policíclicos (HAPs), algunos de los cuales son cancerígenos. Esta serie de compuestos en general está presente en el ambiente como mezclas complejas, presentando un rango muy variado de propiedades químicas, físicas y toxicológicas. En el presente trabajo, se estudió la interacción de sustancias húmicas con fenantreno y antraceno, separados o en mezcla, determinándose los coeficientes de partición (Koc) de las sustancias entre el carbono orgánico disuelto y la fase líquida por una metodología sencilla que utiliza extracción en fase sólida y determinación por espectrofotometría UV-visible. Los valores de Koc obtenidos son comparables con los referidos para estos compuestos por aplicación de otras técnicas. El método descrito es una herramienta que puede ser útil para analizar la interacción de los contaminantes orgánicos hidrofóbicos con las sustancias húmicas

Humic substances are major components of natural water. They are acidic polymers, mostly aromatic and usually harmless. However, they play an important role because they affect bioavailability and toxicity of many compounds in aquatic environments. Polycyclic aromatic hydrocarbons (some of them carcinogenic) are considered to be some of the most common pollutants of aquatic systems. They are usually found in the environment as complex mixtures exhibiting a wide range of physical, chemical and toxicological properties. In the present work, the interaction between humic substances and phenantrene and anthracene, individually or in mixtures, was studied. Partition coefficients of the substances between dissolved organic carbon and liquid phase were estimated by a simple methodology involving solid phase extraction and UVVIS spectrophotometry. Koc values obtained by this means are comparable with those obtained using other methods. The method described is a valuable tool for analyzing interactions of hydrophobic pollutants with humic substances

Exposición a tóxicos de uso industrial y ambiente laboral / No disponible

Existen evidencias epidemiológicas que sugieren la posibilidadde que un importante número de exposicionesprofesionales puedan contribuir a la génesis del cáncerlaríngeo.Con este trabajo hemos pretendido hacer un repaso deaquellas actividades profesionales que implican un aumentodel riesgo de desarrollar cáncer de laringe

Exist epidemiologic evidences about the relationshipamong an important number of professional exposuresthat may contribute to the genesis of a laryngeal cancer.With this article, our purpose has been to revise thoseprofessional activities with high risk for developing alaryngeal carcinoma

Carcinoma de pulmón de origen laboral / Occupational lung cancer

El carcinoma broncopulmonar es la primera causade muerte por cáncer en varones, siendo su principalcausa el consumo de tabaco; no obstante, diversosestudios han atribuido un tanto por ciento no despreciablede su etiología a la exposición laboral a agentesconsiderados cancerígenos como el asbesto, con elque tiene relación la mitad de los casos de cáncer pulmonarde origen laboral. Dada la baja supervivencia deesta patología, son de suma importancia las medidasde prevención encaminadas a identificar los agentescancerígenos y a la disminución de su exposición.Puesto que la presentación clínica no difiere del carcinomarelacionado con el tabaco, un alto grado de sospecha,basado en una cuidadosa historia laboral, esfundamental para su diagnóstico. Debido el efectosinérgico del tabaco, medidas destinadas a disminuirsu consumo, continúan siendo de suma importancia enla población expuesta

Bronchopulmonary carcinoma is the first cause ofdeath by cancer in males, its principal cause beingtobacco consumption. Nonetheless, different studieshave attributed a certain, by no means negligiblepercent of its aetiology to the occupational exposure toagents considered carcinogenic such as asbestos, withwhich half of the cases of occupational lung cancer arerelated. Given the low survival rate of this pathology,preventive measures directed at identifyingcarcinogenic agents and reducing exposure to them areextremely important. Given that the clinicalpresentation does not differ from tobacco-relatedcarcinoma, a high level of suspicion, based on ameticulous occupational history, is fundamental to itsdiagnosis. Due to the synergic effect of tobacco,measures aimed at reducing its consumption continueto be extremely important in the exposed population

XIX Reunión Científica de la SEE: Madrid, 17-19 de Octubre de 2001 / No disponible

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