Environmental radiological baseline in unconventional oil and gas areas of Mexico.

Environmental radioactivity study was performed in unconventional hydrocarbons areas for the first time in Mexico, where four unconventional hydrocarbon exploratory wells (UHEW) are planned. This study assesses natural radiological conditions in areas around UHEW. Equivalent dose rate distribution displayed in Geographic Information System (GIS) had a maximum of 1.83 mSv a-1 and minimum of 0.04 mSv a-1, GIS was also used for introducing land usage, water resources and population occupancy. Measurements of gross alpha and gross beta in water were below the national permissible limits for drinking water 0.5 and 1.0 Bq L-1 respectively, even though samples do not correspond to drinking water. Evaluation of 238U and 226Ra in groundwater were below minimum detectable concentration 1.3 and 1.0 Bq L-1, respectively. This study provides a radiological baseline for the impact of future industrial activities, especially if exploitation of unconventional hydrocarbons produces naturally occurring radioactive material.

Phthalates in the diet of Mexican children of school age. Risk analysis.

Phthalates are widely used as plasticizers, additives, or solvents. Its extensive use has generated environmental and food contamination, which implies continuous population exposure. The aim of this work was to determine the probability of health risk of Mexican children exposed to phthalates through the consumption of contaminated food. A survey was applied to 384 Mexican school-age children (between 6 and 12 years old), to find out the type of food they eat most frequently, based on this, a research was made to know the concentration of phthalates contained in these foods. The daily intake had been calculated with the concentration of phthalates reported in food, obtaining: DEHP (19.50 µg/kg body weight/day), DnBP (5.52 µg/kg body weight/day) y for DEP (1.12 µg/kg body weight/day). The hazard index (HI) for DEP y DEHP was 0.49 to 42.5 for internal organs damage reported. HI for reproductive health damage due to exposure to DnBT and DEHP was of 0.04 to 5.58, so that there is a high probability that children's health is at risk. Therefore, it is necessary to a quantitative analysis of phthalates in food consumed in Latin American countries and establish the TDI of phthalates especially, to DEHP, which was obtained the higher HI.

Penicillium sp. as an organism that degrades endosulfan and reduces its genotoxic effects.

Endosulfan is an organochloride and persistent pesticide that has caused concern because of its impact in the environment and its toxicity to and bioaccumulation in living organisms. In this study, we isolated an endosulfan-degrading fungus from the activated sludge from an industrial wastewater treatment plant. Through repetitive enrichment and successive subculture in media containing endosulfan as the sole carbon source, a fungus designated CHE 23 was isolated. Based on a phylogenetic analysis, strain CHE 23 was assigned to the genus Penicillium sp. In a mineral salt medium with 50 mg/l endosulfan as the sole source carbon, CHE 23 removed the added endosulfan in a period of six days. To verify the decrease in endosulfan toxicity due to the activity of the fungus, we performed genotoxicity tests trough the single cell gel electrophoresis assay or comet assay, with Eisenia fetida as the bioindicator species. This organism was exposed to the supernatants of the culture of the fungus and endosulfan. Our results indicated that the genotoxicity of endosulfan was completely reduced due the activity of this fungus. These results suggest that the Penicillium sp. CHE 23 strain can be used to degrade endosulfan residues and/or for water and soil bioremediation processes without causing toxicity problems, which are probably due to the generation of no-toxic metabolites during biodegradation.

Still's Disease in a Pediatric Patient after Liver Transplantation.

Still's disease (SD) is a multisystemic inflammatory disease characterized by persistent arthritis and in many cases with fever of unknown origin. Diagnosis of SD is challenging because of nonspecific characteristics and especially in the case of a patient with solid organ transplantation and immunosuppressive therapy where multiple causes of fever are possible. There is no diagnostic test for SD, even though some useful diagnostic criteria or laboratory findings, such as serum ferritin levels, have been proposed, and useful imaging studies for the diagnosis or followup of SD have not been developed. We report the case of a 9-year-old child who presented with high grade fever associated with joint pain after a history of liver transplantation and immunosuppressive therapy. Laboratory tests showed increased acute phase reactants, elevated ferritin, and leukocytosis. An 18 F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) was performed identifying abnormal hypermetabolic areas localized in spleen, transplanted liver, and bone marrow secondary to inflammatory process. All infectious, autoimmune, and malignant causes were ruled out. A diagnosis of SD was performed and a steroid-based regimen was initiated with adequate response and no evidence of recurrence. To our knowledge this is the first case of SD following a solid organ transplant.

Correlación entre características mamográficas y resultados anatomopatológicos de lesiones no palpables de pacientes con cáncer de mama. Lima - Perú / Correlation between mammographic characteristics and anatomical pathological results of non-palpable lesions of patients with breast cancer. Lima - Peru

OBJETIVO: El objetivo principal del presente estudio es describir las características radiológicas de las lesiones no palpables de mama y determinar su relación con el estudio anatomopatológico en el Hospital Nacional Edgardo Rebagliati Martins. METODOLOGIA: El tipo de estudio fue observacional-analítico, retrospectivo de corte transversal, cuyo número de muestra fue constituido por las historias clínicas de 159 pacientes con lesiones clínicamente no palpables detectadas por mamografía y confirmadas por biopsia quirúrgica. Se elaboro una ficha de recolección en la que se incluían las características poblacionales, mamográficas y de anatomía patológica de las pacientes. Posteriormente, se creó una base de datos sobre la cual se realizo el análisis aplicando la prueba de Chi-cuadrado y Odds Ratio, según fuera conveniente. RESULTADOS: La cantidad de pacientes estudiadas fue de 159 cuya media de edad fue de 58 +/- 7.9 años. Se hallo que 93.1 por ciento de los casos correspondían a la categoría BIRADS 4.27 por ciento de las pacientes fueron diagnosticadas con cáncer de mama. En cuanto a las lesiones la ubicación lateral más frecuente fue la mama izquierda (56 por ciento) sobre el cuadrante superior externo (36.5 por ciento). La lesión que se hallaba con más frecuencia fue la microcalcificacíón, en 89.9 por ciento de los casos, cuya distribución se concentraba entre las de tipo lineal y grupal con 37.1 por ciento de los casos en cada una, 50 por ciento eran de tipo amorfa, 45.5 por ciento se presentaban en número de menos de 10 por cm2. Las masas correspondían al 23.9 por ciento de los casos, la forma oval es la que mas predominaba con 34.2 por ciento de los casos y el tamaño menor a 1 cm. con 63.2 por ciento de los casos. La distorsión de la arquitectura tenía una frecuencia del 15.1 por ciento. Se encontró una diferencia estadísticamente significativa para la prueba de Chi-cuadrado entre los casos de Efecto de masa y Cáncer de mama (p=0.17), se calculo la asociación para estas variables con un valor de OR = 2.5 IC (), lo cual indica que las pacientes con evidencia mamográfica de masa tienen 2.5 veces más riesgo de desarrollar Cáncer de mama que las que no lo presentan. CONCLUSION: Se encontraron diferencias estadísticamente significativas entre los casos de efecto de masa y cáncer de mama; se calculo que existe un riesgo doblemente mayor de padecer cáncer de mama en aquellas pacientes que presentan masas en la mamografía

Toxicity assessment of a complex industrial wastewater using aquatic and terrestrial bioassays Daphnia pulex and Lactuca sativa.

Aquatic and terrestrial bioassays were used to assess toxicity at several stages in an industrial wastewater treatment plant that processes 400 L/s from a complex influent formed by wastewater from 135 industries. Daphnia pulex and Lactuca sativa were used to assess and compare toxicity between the influent wastewater and effluent wastewater from an activated sludge process, and compare their relationship with physicochemical parameters of Biological Oxygen Demand (BOD); Chemical Oxygen Demand (COD); Total Suspended Solids (TSS); total Nitrogen (N (N-total)), and ammonia Nitrogen (N (N - NH3)). Samples from the primary clarifiers (PC), mix liquor stage (ML) and secondary clarifiers (SC) were processed using physicochemical and bioassay test. Toxicity results with Daphnia pulex showed decreased mean values of acute Toxic Units (a.T.U.) between PC (2.1 a.T.U.) and SC (1,25 a.T.U.). Lactuca sativa showed high values of toxicity between PC and SC (3.37 and 3.32 a.T.U. respectively). Some samples exhibited higher toxicity values at the effluent stage (SC) than the influent stage (PC). The highest correlations of physicochemical properties with toxicity were obtained with COD and nitrogen compounds in effluent samples (SC), but not with influent samples (PC).

New process for fungal delignification of sugar-cane bagasse and simultaneous production of laccase in a vapor phase bioreactor.

We propose a new process using a vapor phase bioreactor (VPB) to simultaneously (i) delignify sugar-cane bagasse, a residue of sugar production that can be recycled in paper industry, and (ii) produce laccase, an enzyme usable to bleach paper pulp. Ethanol vapor, used as laccase inducer, was blown up through a VPB packed with bagasse and inoculated with Pycnoporus cinnabarinusss3, a laccase-hyperproducing fungal strain. After 28 days, the laccase activity in the ethanol-treated bagasse was 80-fold higher (80 U g(ds)(-)(1)) and the bagasse delignification percentage was 12-fold (12%) higher than in the reference samples produced in the absence of ethanol, corresponding to a high overall pulp yield of 96.1%. In the presence of ethanol, the total soluble phenols amount was 2.5-fold (3 mg FA g(ds)(-)(1)) higher than that without ethanol. Six monomeric phenols were detected: p-coumaric (4-hydroxyphenyl-2-propenoic), ferulic (4-hydroxy-3-methoxyphenyl-2-propenoic), syringic (4-hydroxy-3,5-dimethoxybenzoic), vanillic (4-hydroxy-3-methoxybenzoic) and 4-hydroxybenzoic acids, and 2-methoxyhydroquinone. Higher concentrations of phenolic compounds were observed when ethanol vapor was added, confirming a more efficient bagasse delignification. After 28 days, the fungal-treated bagasse (with ethanol addition) was pulped and refined. For a freeness of 81 mL CSF, this processing required 50% less energy than with untreated bagasse (without inoculation and ethanol addition), which indicated a significant potential economy for the pulp and paper industry. Handsheets were made from pulp obtained after fungal-treated and untreated bagasse. Comparison of bagasse-pulp characteristics for freeness of 35 and 181 mL CSF showed an average increment by 35% for tensile index and breaking strength and length. VPB allowed a simultaneous production of laccase (90 U g(ds)(-)(1), after pressing of the bagasse) that improved the overall profitability of the process.

El hábito de fumar en pacientes con periodontitis: características clínicas / The smoking habit in patients with periodontitis: clinical characteristics

Este estudio fue de tipo descriptivo comparativo correlacional, con un diseño no experimental. El objetivo fue identificar las características clínicas del periodonto de pacientes fumadores con periodontitis que asistían a la Facultad de Odontología de la Pontificia Universidad Javeriana. La población del estudio incluyó pacientes de posgrado, fumadores y no fumadores, con periodontitis, sin tratamiento previo, que aistieron a la Facultad de Odontología de la Universidad Javeriana en el año 1996 y el primer semestre de 1997. El estudio se realizó con 115 pacientes a los que se les observaron las características clínicas periodontales, se les aplicó una encuesta con el fin de identificar los que presentaban el hábito de fumar y, posteriormente, se compararon los datos entre los pacientes fumadores y no fumadores. Se aplicaron pruebas de estadística descriptiva que incluyeron medidas de tendencia central y de dispersión. Se encontró que el hábito de fumar incluye principalmente en la profundidad de la bolsa, la pérdida ósea, la pérdida de nivel de inserción clínica y la hemorragia. El hábito de fumar no influye sobre el porcentaje de placa bacteriana, ya que en los pacientes fumadores se encontró una menor proporción de ésta en relación con los no fumadores