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We present the case of a male patient in the sixth decade of life who attended due to the presence of progressive increase in abdominal circumference, accompanied by early satiety, to which generalized jaundice was later added, finding Gigot III polycystic liver disease by imaging methods.

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El propósito del presente estudio fue estimar la toxicidad del pesticidas carbofurán sobre los parámetros hematológicos (hematocrito, hemoglobina, glucosa en la sangre y conteo de eritrocitos y leucocitos totales), sobre la excreción de amoníaco y el consumo de oxígeno en individuos juveniles de Oreochromis niloticus (longitud total: 12±0,5 mm). Los espécimenes fueron expuestos a diferentes concentraciones del plaguicida carbofurán (0, 0,1, 0,5, 1,0, 2,0, y 4,0 mg L-1), a diferentes temperaturas (15, 20 y 25 °C) y pH 7. Los valores de LC50 en períodos de 24, 48, 72, 96 h para los juveniles de O. niloticus expuestos al carbofurán fueron 3,00; 2,84; 2,71 e 2,45 mg L−1 para 15 °C; 3,00; 2,69; 2,33 e 2,20 mg L−1 para 20 °C; y 2,84; 2,44; 1,71; 1,62 mg L−1 para 25 °C, respectivamente. Los resultados evidenciaron que con el aumento de la temperatura de 15 a 25 °C hubo un aumento de la sensibilidad de los peces al carbofurán de 21,80%, 9,55%, 31,92% y 30,87%, después de 24, 48, 72 y 96 h de exposición, respectivamente. Por otra parte, se observó que en peces expuestos al carbofurán en concentración de 2 mg L-1 ocurrió una disminución en la tasa de hemoglobina total y una elevación en la tasa de glucosa sanguínea, consumo de oxígeno y excreción de amonio. Estos resultados indican que la exposición al carbofurán, especialmente a altas temperaturas es un factor significativo a ser considerado en el manejo de la acuacultura.

Oreochromis niloticus juveniles (total length 12±0.5 mm) were exposed to different concentrations of carbofuran, using the static renewal method at different temperatures (15, 20 and 25°C) at pH 7. The 24, 48, 72, 96 h LC50 values of carbofuran in Oreochromis niloticus juveniles were 3.00, 2.84, 2.71 and 2.45 mg L−1 at 15°C; 3.00, 2.69, 2.33 and 2.20 mg L−1 at 20°C; and 2.84, 2.44, 1.7 1 and 1.62 mg L−1 at 25°C, respectively. Results show that a temperature increment from 15 to 25°C increased the carbofuran susceptibility in fish by 21.80%, 9.55%, 31.92% and 30.87%, after 24, 48, 72 and 96 hours of exposure, respectively. Furthermore, we found that exposure of fish to carbofuran caused an elevation in total hemoglobin and blood glucose concentration of 2 mg L-1. These results indicate that exposure to carbofuran, especially at lower temperatures is a significant factor to be considered in aquaculture management.

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El propósito del presente estudio fue estimar la toxicidad del pesticidas carbofurán sobre los parámetros hematológicos (hematocrito, hemoglobina, glucosa en la sangre y conteo de eritrocitos y leucocitos totales), sobre la excreción de amoníaco y el consumo de oxígeno en individuos juveniles de Oreochromis niloticus (longitud total: 12±0,5 mm). Los espécimenes fueron expuestos a diferentes concentraciones del plaguicida carbofurán (0, 0,1, 0,5, 1,0, 2,0, y 4,0 mg L-1), a diferentes temperaturas (15, 20 y 25 °C) y pH 7. Los valores de LC50 en períodos de 24, 48, 72, 96 h para los juveniles de O. niloticus expuestos al carbofurán fueron 3,00; 2,84; 2,71 e 2,45 mg L−1 para 15 °C; 3,00; 2,69; 2,33 e 2,20 mg L−1 para 20 °C; y 2,84; 2,44; 1,71; 1,62 mg L−1 para 25 °C, respectivamente. Los resultados evidenciaron que con el aumento de la temperatura de 15 a 25 °C hubo un aumento de la sensibilidad de los peces al carbofurán de 21,80%, 9,55%, 31,92% y 30,87%, después de 24, 48, 72 y 96 h de exposición, respectivamente. Por otra parte, se observó que en peces expuestos al carbofurán en concentración de 2 mg L-1 ocurrió una disminución en la tasa de hemoglobina total y una elevación en la tasa de glucosa sanguínea, consumo de oxígeno y excreción de amonio. Estos resultados indican que la exposición al carbofurán, especialmente a altas temperaturas es un factor significativo a ser considerado en el manejo de la acuacultura.(AU)

Oreochromis niloticus juveniles (total length 12±0.5 mm) were exposed to different concentrations of carbofuran, using the static renewal method at different temperatures (15, 20 and 25°C) at pH 7. The 24, 48, 72, 96 h LC50 values of carbofuran in Oreochromis niloticus juveniles were 3.00, 2.84, 2.71 and 2.45 mg L−1 at 15°C; 3.00, 2.69, 2.33 and 2.20 mg L−1 at 20°C; and 2.84, 2.44, 1.7 1 and 1.62 mg L−1 at 25°C, respectively. Results show that a temperature increment from 15 to 25°C increased the carbofuran susceptibility in fish by 21.80%, 9.55%, 31.92% and 30.87%, after 24, 48, 72 and 96 hours of exposure, respectively. Furthermore, we found that exposure of fish to carbofuran caused an elevation in total hemoglobin and blood glucose concentration of 2 mg L-1. These results indicate that exposure to carbofuran, especially at lower temperatures is a significant factor to be considered in aquaculture management.(AU)

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Biomixtures are used for the removal of pesticides from agricultural wastewater. As biomixtures employ high content of lignocellulosic substrates, their bioaugmentation with ligninolytic fungi represents a novel approach for their enhancement. Nonetheless, the decrease in the concentration of the pesticide may result in sublethal concentrations that still affect ecosystems. Two matrices, a microcosm of rice husk (lignocellulosic substrate) bioaugmented with the fungus Trametes versicolor and a biomixture that contained fungally colonized rice husk were used in the degradation of the insecticide/nematicide carbofuran (CFN). Elutriates simulating lixiviates from these matrices were used to assay the ecotoxicological effects at sublethal level over Daphnia magna (Straus) and the fish Oreochromis aureus (Steindachner) and Oncorhynchus mykiss (Walbaum). Elutriates obtained after 30 d of treatment in the rice husk microcosms at dilutions over 2.5% increased the offspring of D. magna as a trade-off stress response, and produced mortality of neonates at dilutions over 5%. Elutriates (dilution 1:200) obtained during a 30 d period did not produce alterations on the oxygen consumption and ammonium excretion of O. mykiss, however these physiological parameters were affected in O. aureus at every time point of treatment, irrespective of the decrease in CFN concentration. When the fungally colonized rice husk was used to prepare a biomixture, where more accelerated degradation is expected, similar alterations on the responses by O. aureus were achieved. Results suggest that despite the good removal of the pesticide, it is necessary to optimize biomixtures to minimize their residual toxicity and potential chronic effects on aquatic life.

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Carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate; C12H15NO3) is one of the most toxic carbamate pesticides. For acute toxicity of carbofuran, juveniles of Macrobrachium olfersii were exposed to different concentrations of carbofuran using the static renewal method at different temperature levels (15, 20 and 25°C) at pH 7.0. The main purpose of the present study was to detect the acute toxicity of carbofuran to M. olfersii and investigate its effects on oxygen consumption and ammonium excretion; these tests have not been carried out in this species before. First, the acute toxicity - median lethal concentration - of carbofuran to M. olfersii for 24, 48, 72 and 96 h was examined, which resulted in the following values: 1.64, 1.22, 0.86 and 0.42 mg L(-1), respectively. Furthermore, we also found that carbofuran caused an inhibition in oxygen consumption of 60.6, 65.3 and 66.2% with respect to the control. In addition, after separate exposures to carbofuran, elevations in ammonium excretion were more than 500% with respect to the control.

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Pesticide biopurification systems contain a biologically active matrix (biomixture) responsible for the accelerated elimination of pesticides in wastewaters derived from pest control in crop fields. Biomixtures have been typically prepared using the volumetric composition 50:25:25 (lignocellulosic substrate/humic component/soil); nonetheless, formal composition optimization has not been performed so far. Carbofuran is an insecticide/nematicide of high toxicity widely employed in developing countries. Therefore, the composition of a highly efficient biomixture (composed of coconut fiber, compost, and soil, FCS) for the removal of carbofuran was optimized by means of a central composite design and response surface methodology. The volumetric content of soil and the ratio coconut fiber/compost were used as the design variables. The performance of the biomixture was assayed by considering the elimination of carbofuran, the mineralization of (14)C-carbofuran, and the residual toxicity of the matrix, as response variables. Based on the models, the optimal volumetric composition of the FCS biomixture consists of 45:13:42 (coconut fiber/compost/soil), which resulted in minimal residual toxicity and ∼99% carbofuran elimination after 3 days. This optimized biomixture considerably differs from the standard 50:25:25 composition, which remarks the importance of assessing the performance of newly developed biomixtures during the design of biopurification systems.

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A biomixture constitutes the active core of the on-farm biopurification systems, employed for the detoxification of pesticide-containing wastewaters. As biomixtures should be prepared considering the available local materials, the present work aimed to evaluate the performance of ten different biomixtures elaborated with by-products from local farming, in the degradation of the insecticide/nematicide carbofuran (CFN), in order to identify suitable autochthonous biomixtures to be used in the tropics. Five different lignocellulosic materials mixed with either compost or peat and soil were employed in the preparation of the biomixtures. The comprehensive evaluation of the biomixtures included removal of the parent compound, formation of transformation products, mineralization of radiolabeled CFN, and determination of the residual toxicity of the process. Detoxification capacity of the matrices was high, and compost-based biomixtures showed better performance than peat-based biomixtures. CFN removal over 98.5% was achieved within 16 days (eight out of ten biomixtures), with half-lives below 5 days in most of the cases. 3-Hydroxycarbofuran and 3-ketocarbofuran were found as transformation products at very low concentrations suggesting their further degradation. Mineralization of CFN was also achieved after 64 days (2.9 to 15.1%); several biomixtures presented higher mineralization than the soil itself. Acute toxicity determinations with Daphnia magna revealed a marked detoxification in the matrices at the end of the process; low residual toxicity was observed only in two of the peat-based biomixtures. Overall best efficiency was achieved with the biomixture composed of coconut fiber-compost-soil; however, results suggest that in the case of unavailability of coconut fiber, other biomixtures may be employed with similar performance.

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Se utilizó el programa Pesticide Impact Rating Index (PIRI) para estimar la peligrosidad del uso de 30 plaguicidas en elcultivo de cebolla (Allium cepa L.) para la calidad del agua de la quebrada Sanatorio, ubicada en la comunidad de TierraBlanca, en el cantón de Cartago, Costa Rica. La información se obtuvo del Servicio Fitosanitario del Estado y de encuestasaplicadas a los productores de la zona de Tierra Blanca. Los resultados obtenidos con el PIRI se contrastaron con los nivelesde residuos de plaguicidas en sedimentos y agua encontrados en la quebrada en el monitoreo realizado durante losmeses de abril, junio, agosto y octubre del 2011. Aproximadamente el 50% de los plaguicidas autorizados se clasificaroncomo extremadamente tóxicos, y cerca del 40% se clasificaron como muy móviles. Por otro lado, de los plaguicidas noregistrados, el 60% fue catalogado como extremadamente tóxicos, y el 40% como muy móviles. El agua de la quebrada esutilizada para riego de los cultivos de fincas aledañas al cauce, por lo que esta situación podría representar un problemasobre la salud pública.

Usou-se o programa Pesticide Impact Rating Index (PIRI) para estimar o risco do uso de 30 inseticidas no cultivo dacebola (Allium cepa L.) para a qualidade da água de quebrada Sanatorio, localizado na comunidade de Terra Branca, nocantão de Cartago, Costa Rica. Obtiveram-se informações do Serviço Fitossanitário do Estado e de pesquisas feitas juntoaos produtores da área de Terra Branca. Os resultados obtidos com o PIRI confirmaram os níveis de resíduos de inseticidaem sedimento e água encontrada na quebrada em uma monitoração realizada durante abril, junho, agosto e outubro de2011. Aproximadamente 50% dos inseticidas autorizados mostraram-se extremamente venenosos, e perto de 40% comomuito móveis. Por outro lado, dos inseticidas não registrados, 60% catalogaram-se como extremamente venenosos, e40%, como muito móveis. A água quebrada é usada para a irrigação do cultivo de fazendas próximas do leito do rio,situação que pode gerar problemas de saúde pública.

Using the program Pesticide Impact Rating Index (PIRI) to estimate the risk of the use of 30 insecticides in the cultivationof onion (Allium cepa L.) for water quality from quebrada Sanatorio, located in the community of Tierra Blanca,in the canton of Carthage, Costa Rica. Information was obtained from the Phytosanitary Service of the State (ServicioFitosanitario del Estado) and from surveys applied to the producers of the area of Tierra. The results obtained with PIRIwere confirmed at the levels of residues of insecticides in sediments and water found in the gorge in a monitoringrealized during April, June, August and October, 2011. Approximately 50% of the authorized insecticides qualifiedas extremely poisonous, and close to 40% qualified as very mobile. On the other hand, from the non registered insecticides,60% were catalogued as extremely poisonous, and 40% as very mobile. The water of the gorge is used forirrigation of the cultivation of bordering farms to the river bed, and for that reason this situation can generate problemson public health.

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Environmental contamination with pesticides is an undesired consequence of agricultural activities. Biopurification systems (BPS) comprise a novel strategy to degrade pesticides from contaminated wastewaters, consisting of a highly active biological mixture confined in a container or excavation. The design of BPS promotes microbial activity, in particular by white rot fungi (WRF). Due to their physiological features, specifically the production of highly unspecific ligninolytic enzymes and some intracellular enzymatic complexes, WRF show the ability to transform a wide range of organic pollutants. This minireview summarizes the potential participation of WRF in BPS. The first part presents the potential use of WRF in biodegradation of pollutants, particularly pesticides, and includes a brief description of the enzymatic systems involved in their oxidation. The second part presents an outline of BPS, focusing on the elements that influence the participation of WRF in their operation, and includes a summary of the studies regarding the fungal-mediated degradation of pesticides in BPS biomixtures and other solid-phase systems that mimic BPS.

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Penaeid shrimps are important resources for worldwide fisheries and aquaculture. In Brazil, Xiphopenaeus kroyeriis an important commercially exploited species, and is an ideal animal for studying the impairment caused by the effects of heavy metals that are often detected in coastal areas. The main purpose of the present study was to detect the acute toxicity of Cd and Zn to X.kroyeriand to investigate their effects on oxygen consumption and ammonium excretion in different temperatures (25 ºC, 20 ºC, 15 ºC), which have not been carried out in this species before. First of all, we examined the acute toxicity of Cd and Zn to X. kroyeri24, 48, 72, and 96-h medium lethal concentration (LC50). Furthermore, we also found that exposure of shrimp to Cd and Zn caused an inhibition in oxygen consumption of 52.50% and 52.63%, respectively, relative to the control. However, after separate exposure to Cd and Zn, elevations in ammonium excretion were obtained, which were 85.00% and 89.47% higher than the control, respectively. The results shown that Cd and Zn performs higher toxicities toX. kroyeriat higher temperature.(AU)

Os camarões são importantes recursos marinhos explorados pela pesca e aquicultura. No Brasil, Xiphopenaeus kroyerié uma importante espécie comercialmente explorada e um animal ideal para estudar o impacto causado por efeitos de metais pesados que frequentemente são detectados em áreas costeiras. O principal objetivo do presente trabalho foi determinar a toxicidade aguda do Cd e Zn para o X. kroyerie investigar seus efeitos no consumo de oxigênio e na excreção de amônia em diferentes temperaturas, uma vez que tais parâmetros ainda não foram determinados para a referida espécie. Primeiramente, foram determinadas a toxicidade aguda (LC50) do Cd e Zn, para X.kroyeripor um período de 24, 48, 72 e 96 horas em três temperaturas (25 ºC, 20 ºC, 15 ºC). Os resultados revelaram que para camarões expostos ao Cd e Zn houve uma inibição do consumo de oxigênio de 52,50% e 52,63%, respectivamente, para a mais baixa temperatura (15 °C). Entretanto, para a excreção de amônia, houve um aumento de 85,00% e 89,47%para a mais alta concentração e temperatura utilizadas em relação ao controle. Conclui-se, portanto, que as toxicidades de Cd e Zn foram mais altas nas temperaturas e concentrações mais elevadas.(AU)

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Penaeid shrimps are important resources for worldwide fisheries and aquaculture. In Brazil, Xiphopenaeus kroyeri is an important commercially exploited species, and is an ideal animal for studying the impairment caused by the effects of heavy metals that are often detected in coastal areas. The main purpose of the present study was to detect the acute toxicity of Cd and Zn to X. kroyeri and to investigate their effects on oxygen consumption and ammonium excretion in different temperatures (25 ºC, 20 ºC, 15 ºC), which have not been carried out in this species before. First of all, we examined the acute toxicity of Cd and Zn to X. kroyeri 24, 48, 72, and 96-h medium lethal concentration (LC50). Furthermore, we also found that exposure of shrimp to Cd and Zn caused an inhibition in oxygen consumption of 52.50% and 52.63%, respectively, relative to the control. However, after separate exposure to Cd and Zn, elevations in ammonium excretion were obtained, which were 85.00% and 89.47% higher than the control, respectively. The results shown that Cd and Zn performs higher toxicities to X. kroyeri at higher temperature.

Os camarões são importantes recursos marinhos explorados pela pesca e aquicultura. No Brasil, Xiphopenaeus kroyeri é uma importante espécie comercialmente explorada e um animal ideal para estudar o impacto causado por efeitos de metais pesados que frequentemente são detectados em áreas costeiras. O principal objetivo do presente trabalho foi determinar a toxicidade aguda do Cd e Zn para o X. kroyeri e investigar seus efeitos no consumo de oxigênio e na excreção de amônia em diferentes temperaturas, uma vez que tais parâmetros ainda não foram determinados para a referida espécie. Primeiramente, foram determinadas a toxicidade aguda (LC50) do Cd e Zn, para X. kroyeri por um período de 24, 48, 72 e 96 horas em três temperaturas (25 ºC, 20 ºC, 15 ºC). Os resultados revelaram que para camarões expostos ao Cd e Zn houve uma inibição do consumo de oxigênio de 52,50% e 52,63%, respectivamente, para a mais baixa temperatura (15 C). Entretanto, para a excreção de amônia, houve um aumento de 85,00% e 89,47% para a mais alta concentração e temperatura utilizadas em relação ao controle. Conclui-se, portanto, que as toxicidades de Cd e Zn foram mais altas nas temperaturas e concentrações mais elevadas.

RESUMO

En el marco del proyecto Manejo de plagas a nivel comunitario en la agricultura centro americana, se diseñó un programa de capacitaciones denominado Prácticas agrícolas y su relación con la salud humana, para agricultores de tres comunidades del norte de Cartago, Costa Rica. La capacitación se dividió en tres charlas: efecto de plaguicidas sobre el cuerpo humano; sobre la familia y el ambiente; y salud ocupacional enfocada en el manejo de plaguicidas. Además, se realizó la recolección de muestras sanguíneas de participantes para el análisis de las enzimas colinesterasa eritrocítica (AChE) y plasmática (PChE), indicadores de exposición aplaguicidas organofosforados y carbamatos. En situaciones de intoxicación por estos plaguicidas, la PChE disminuye rápidamente(exposición aguda), mientras que la AChE es un indicador de exposición crónica, al permanecer disminuida mayor tiempo y sermenos afectada por condiciones clínicas. Fueron determinados los niveles de colinesterasas al inicio y final de la capacitación, paradetectar posibles cambios en la actividad enzimática, como resultado de la participación en las charlas. En ambas recolecciones,todos los participantes presentaron niveles de actividad enzimática dentro de los valores de referencia (varones PChE 4500-9900U/L; AChE 4000-6800 U/L). Únicamente en un grupo (Pacayas) hubo diferencia entre la actividad de PChE antes de las charlas ydespués de estas (t= -3,87, gL=10, p=0,003). Mediante este programa, se brindaron nuevos conocimientos sobre la importancia del uso de buenas prácticas agrícolas (BPA), los cuales se traducen en efectos positivos en la salud humana, familiar y ambiental.

Under the project Pest management at the community level in Central American agriculture, we designed a training programcalled Farming practices and their relation to human health, to farmers in three communities located north of Cartago, Costa Rica. The training was divided into three lectures: Effect of pesticides on the human body; on the family and environment;and occupational health focused on pesticide management. Moreover, blood samples of participants were collected for theanalysis of erythrocyte cholinesterase (AChE) and plasma (PChE) enzymes, indicators of exposure to organophosphate and carbamate pesticides. In these pesticide poisoning, the PChE decreases rapidly (acute exposure), whereas AChE is an indicatorof chronic exposure decreased to remain longer and be less affected by clinical conditions. At beginning and end of the training, it was determined cholinesterase levels, to detect changes in enzyme activity as a result of participation in the talks.In both collections, all participants had levels of enzyme activity with in the reference values (males PChE 4500-9900 U / L;AChE 4000-6800 U / L). Only one group (Pacayas) shows difference between the activity of PChE before and after these talks (t= -3.87, df = 10, p = 0.003). Through this program, new insights were provided into the importance of using good agricultural practices (GAP), which result in positive effects on human health, environment and family.

No âmbito do projeto Manejo de plagas a nivel comunitario en la agricultura centro americana, foi elaborado um programa de treinamento chamado Prácticas agrícolas y su relación con la salud humana para os agricultores de três comunidades ao norte de Cartago, Costa Rica. O treinamento foi adaptado e dividido em três palestras: efeito de pesticidas sobre o corpo humano,sobre a Família e Meio Ambiente e Saúde Ocupacional focada em gestão de pesticidas. Além disso, realizou-se a coleta deamostras de sangue dos sujeitos para análise da enzima colinesterase eritrocitária (AChE) e plasma (PChE), indicadores de exposição a compostos organofosforados e carbamatos. Nestas intoxicações por agrotóxicos, o PChE diminui rapidamente(exposição aguda), enquanto o AChE, um indicador de exposição crônica, diminui ao permanecer por mais tempo e ser menos afetado pelas condições clínicas. Foram determinados níveis de colinesterase no início e no final do treinamento, para detectar mudanças na atividade da enzima como resultado da participação nas atividades. Em ambos os conjuntos, todos os participantes tinham níveis de atividade enzimática dentro dos valores de referência (sujeitos do sexo masculino: PChE 4500-9900U / L; AChE 4000-6800 U / L). Apenas num grupo (Pacayas) houve diferença entre a atividade da PChE antes e depois destas conversas (t = -3,87, gl = 10, p = 0,003). Através deste programa, proposuram-se novos insights sobre a importância do uso de boas práticas agrícolas (GAP) que resultam em efeitos positivos sobre a saúde humana, meio ambiente e família.

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Se monitoreó la calidad del agua de la Quebrada Sanatorio (Tierra Blanca, Cartago, Costa Rica), durante abril, junio, agosto y octubre de 2011. Se establecieron tres puntos de muestreo utilizando una metodología de estratificación. Se realizó un análisis biofísico de la zona de estudio, así como la caracterización fisicoquímica y microbiológica del cuerpo de agua, determinación de residuos de plaguicidas en agua y sedimentos y aplicación de índice BMWP adaptado a Costa Rica. Se determinó una elevada contaminación en la quebrada por coliformes fecales y E. coli, nutrientes y plaguicidas, quefueron detectados en agua y sedimentos, demás se determinó una deficiente calidad del recurso hídrico según el índice BMWP-CR. Se concluye que el agua no es adecuada para riego y pone en riesgo la salud de los agricultores, sus familias y consumidores, así como se ve afectada la seguridad alimentaria.

This project was monitoring water quality of the stream “Quebrada Sanatorio” (Tierra Blanca, Cartago, Costa Rica), during April, June, August and October 2011. It established three sampling points using a stratification methodology. It was performed biophysical analysis of the area of study. It was determined physicochemical and microbiological characteristics of thewater body, determination of pesticide residues in water and sediments and application BMWP index adapted to Costa Rica.It was established high contamination in the stream for faecal coliforms and E. coli, also nutrients and pesticides in water and sediments. It was also determined poor quality of water resources by the index BMWP-CR. It is concluded that the water is not suitable for irrigation and it had a risks the health of farmers, their families and consumers, as well as food security is affected.

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The RUNX1/AML1 gene is the most frequent target for chromosomal translocation, and often identified as a site for reciprocal rearrangement of chromosomes 8 and 21 in patients with acute myelogenous leukemia. Virtually all chromosome translocations in leukemia show no consistent homologous sequences at the breakpoint regions. However, specific chromatin elements (DNase I and topoisomerase II cleavage) have been found at the breakpoints of some genes suggesting that structural motifs are determinant for the double strand DNA-breaks. We analyzed the chromatin organization at intron 5 of the RUNX1 gene where all the sequenced breakpoints involved in t(8;21) have been mapped. Using chromatin immunoprecipitation assays we show that chromatin organization at intron 5 of the RUNX1 gene is different in HL-60 and HeLa cells. Two distinct features mark the intron 5 in cells expressing RUNX1: a complete lack or significantly reduced levels of Histone H1 and enrichment of hyperacetylated histone H3. Strikingly, induction of DNA damage resulted in formation of t(8;21) in HL-60 but not in HeLa cells. Taken together, our results suggest that H1 depletion and/or histone H3 hyperacetylation may have a linkage with an increase susceptibility of specific chromosomal regions to undergo translocations.

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En los últimos años, la participación del sistema inmune innato en el desarrollo de la pre-eclampsia ha sido el objetivo de numerosos estudios. Sin embargo, el rol de las células agresoras naturales (NK) en esta patología no ha sido totalmente aclarado. Las células NK, componentes del sistema inmune innato, poseen actividad citotóxica espontánea, y secretan citoquinas tales como interferón gamma (INF-y ) y Factor de Necrosis Tumoral alfa (TNF-alfa). En el presente estudio hemos analizado la actividad funcional y el inmunofenotipo de células NK obtenidas desde sangre periférica de pacientes con pre-eclampsia, mujeres sanas embarazadas y mujeres sanas no embarazadas. Se cuantificó la actividad cititóxica usando el ensayo de liberación de51cromo. La producción de citoquinas en respuesta a activadores policlonales y el inmunofenotipo (CD3-CD16+CD56+) fueron determinados por citometría de flujo. Estos parámetros no evidenciaron diferencias significativas entre los grupos estudiados; sin embargo, en las pacientes con pre-eclampsia se observa una tendencia hacia una menor citotoxicidad y menor producción de TNF-alfa en células NK estimulada sin vitro, y una proporción aumentada del subtipo celular NK CD56-CD16+ en sangre periférica en relación con los otros dos grupos estudiados.

NK cells functionality during pregnancy. During the last few years, the role of innate immune system in development of pre-eclampsia has been the focus of a number of studies. However, the role of natural killer (NK) cells in pregnancy and pre-eclampsia has not been totally clarified. NK cells, an important component of innate immune system, normally exhibit spontaneus cytolytic activity and secrete cytokines such as interferon gamma (IFN-y) and tumor necrosis factor alpha (TNF-alpha). In current paper, we studied functional activity and immunophenotype of peripheral blood NKcells obtained from patients with pre-eclampsia, healthy pregnant women and non-pregnant healthy women. For this purpose, we quantified cytolytic activity using 51chromium release assay. We determined cytokine production in response to polyclonal activators and cells immunophenotype (CD3-CD16+CD56+) by flow cytometry. We found no significant differences in these parameters among the three groups studied, however, in patients with pre-eclampsia, there is a tendency to a decreased cytotoxic activity and less production of TNF-alpha by NK cells in vitro as well as an increased proportion of the NK subset CD56-CD16+, in peripheral blood.

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