ABSTRACT The objective of this work was to formulate and prepare alkyd paints with new anticorrosive pigments based on exchanged mordenite, friendly with the environment. The electrochemical characterization of painted steel was done by: conductivity measurements, linear polarizations essays and corrosion potential measurements. The paint film tested in this case was removed and the steel surface analysed by scanning electron microscopy and energy dispersive X-ray analysis. The results showed that the new pigments incorporated in the paint have acceptable anticorrosive properties, taking into account their low environmental impact and the use of a low-cost natural resource.

RESUMEN El presente trabajo tuvo como objetivo la formulación y elaboración de pinturas alquídicas con nuevos pigmentos anticorrosivos a base de mordenita intercambiada, amigables con el medio ambiente. La caracterización electroquímica del acero pintado se llevó a cabo por: medidas de conductividad, ensayos de polarización lineal y medidas del potencial de corrosión. La película de pintura ensayada en cada caso fue removida y la superficie fue analizada mediante microscopía electrónica de barrido y análisis de energía dispersiva por rayos X. Los resultados muestran que los nuevos pigmentos incorporados a la pintura proporcionan propiedades anticorrosivas aceptables teniendo en cuenta su bajo impacto ambiental y la utilización de un recurso natural de bajo costo.

Abstract It is important to have forest seeds in sufficient quality and quantity in order to alleviate and reverse the processes of deforestation and land use change that occur at local, national and global levels; therefore, the objective of the present study was to evaluate the productive potential of cones and seeds in two pine species of the El Salto region in Pueblo Nuevo, Durango, Mexico. A total of 63 specimens of Pinus cooperi and 53 of Pinus durangensis were sampled; an average of five cones were collected from each individual, and the total number of the remaining cones in the whole crown of each tree was counted; the length, diameter and biological potential of each cone was determined, and the seeds were classified as infested, aborted and viable, based on X-ray tests. The results showed that only 17 % of the P. cooperi and 21 % of P. durangensis seeds in the region are viable, 34 % and 27 %, respectively, are aborted, and 49 % and 52 % are infested with pests. No statistical differences were found for the variables of the cones and seeds in P. durangensis (α≤0.05 %); however, for P. cooperi, statistical differences were obtained in cone length, biological potential, and developed seeds.

Resumen La necesidad de disponer de semillas forestales de calidad y en cantidad suficiente es importante para mitigar y revertir los procesos de deforestación y de cambio de uso de suelo que ocurren a nivel local, nacional y mundial; por tanto, el objetivo del presente estudio fue evaluar el potencial productivo de conos y semillas de dos especies de pino en la región de El Salto, Pueblo Nuevo, Durango, México. Se muestrearon 63 ejemplares de Pinus cooperi y 53 de Pinus durangensis; de cada árbol se recolectaron, en promedio, cinco conos y se contabilizó el total existente en toda la copa; se determinó la longitud, diámetro y el potencial biológico de cada cono, y se clasificaron las semillas como plagadas, abortadas y viables, mediante pruebas de rayos X. Los resultados mostraron que solo 17 % de las pertenecientes a P. cooperi y 21 % de P. durangensis fueron viables; 34 % y 27 % correspondieron a la categoría de abortadas; mientras que, 49 % y 52 %, respectivamente presentaron plagas. No se obtuvieron diferencias estadísticas para las variables de los conos y semillas en P. durangensis (α≤0.05%); sin embargo, para P. cooperi sí se registraron en la longitud del cono, potencial biológico y semillas desarrolladas.

ABSTRACT Xanthogaleruca luteola (Coleoptera: Chrysomelidae) is an aggressive defoliating pest on elms (Ulmus sp.) worldwide. We evaluated the antifeedant and insecticidal effects of ethanolic and aqueous extracts from Melia azedarach L. green fruits and leaves of Peumus boldus Molina, on X. luteola third instar larvae, the most harmful stage. Five doses of the extracts were applied to fresh elm leaves to determine antifeedant effect evaluating consumed foliar area at 24 h. Insecticidal activity was assessed through daily mortality for 14 d. For each extract an antifeedant index, relative to respective control, and mean lethal concentrations (LC50) were calculated. We found a direct relationship between concentration and both antifeedant and insecticidal effects for all extracts. A dose of 6.1% w/v of ethanolic extract of M. azedarach green fruits significantly inhibited larvae feeding behavior by 91% with a LC50 1.49% at day 8. On the other hand, 3.4% w/v of ethanolic extract of P. boldus inhibited larvae feeding behavior by 81% and LC50 at day 8 was 0.92% w/v. All extracts showed insecticidal effect on X. luteola larvae, and the highest mortalities observed were 79% and 71% with ethanolic and aqueous extracts of P. boldus, respectively. Antifeedant and insecticidal effects observed with M. azedarach green fruits and P. boldus leaf extracts on X. luteola third instar larvae, support the development of botanical insecticides from both tree species in order to contribute to its integrated management.

Introducción: la infección oculta por el virus de la hepatitis B (VHB) se caracteriza por la presencia del genoma viral en suero y/o tejido hepático de individuos negativos para el antígeno de superficie HBsAg. La infección oculta se ha asociado con el desarrollo de cirrosis y carcinoma hepatocelular. Objetivo: identificar casos de infección oculta por el VHB en pacientes con diagnóstico de cirrosis y carcinoma hepatocelular, sometidos a trasplante hepático. Materiales y métodos: entre febrero de 2013 y marzo de 2014 fueron obtenidas muestras de explante hepático provenientes de pacientes con diagnóstico de cirrosis y/o carcinoma hepatocelular. Se detectó el genoma del VHB mediante amplificación de tres regiones del genoma viral (S, Core y X). Las muestras positivas se confirmaron por reacción en cadena de la polimerasa (PCR) en tiempo real para la región S. Resultados: se analizaron 15 muestras de tejido hepático, y en dos (13,3%) se detectó el genoma del VHB mediante PCR anidada para la región S y por PCR semianidada para la región X, resultado confirmado por PCR en tiempo real. Estas muestras provenían de pacientes negativos para los marcadores serológicos de infección por el VHB, anti-HBc y anti-HBs. Conclusión: la frecuencia de infección oculta reportada en este estudio es similar a lo reportado en Brasil en muestras de biopsias obtenidas de pacientes con hepatitis crónica. Estudios adicionales son necesarios para estimar la frecuencia de infección oculta por VHB (OBI) en pacientes con hepatopatías terminales en Colombia

Introduction: Occult hepatitis B virus infection is characterized by the presence of the viral genome in serum and/or liver tissue from individuals who test negative for the HBsAg surface antigen. Occult infection has been associated with the development of cirrhosis and hepatocellular carcinoma. Objective: The objective of this study was to identify cases of occult hepatitis B virus infection in patients with cirrhosis and/or hepatocellular carcinoma undergoing liver transplantation. Materials and methods: Between February 2013 and March 2014 hepatic explant samples were obtained from patients with cirrhosis and/or hepatocellular carcinoma. The hepatitis B virus genome was detected by amplification of three regions of the viral genome (S, Core and X). Positive samples were confirmed by real-time PCR for the S region. Results: Fifteen hepatic tissue samples were analyzed. The genome of the hepatitis B virus was detected in two (13.3%) samples by nested PCR for the S region and by semi-nested PCR for region X. The results were confirmed by real-time PCR. These samples came from patients who had tested negative for anti-HBc and anti-HBs serological markers for hepatitis B virus infection. Conclusion: The frequency of occult infection reported in this study is similar to that reported in Brazil in biopsy specimens obtained from patients with chronic hepatitis. Additional studies are needed to estimate the frequency of occult hepatitis B in patients with end-stage liver disease in Colombia

Bleeding disorders are commonly associated with hemato-oncologic diseases. We report a 68 years old male with a chronic myelomonocytic leukemia derived from a long lasting mielodysplastic syndrome that did not respond to treatment with Azacitidine. The patient was hospitalized due to tonic clonic seizures. A CAT scan showed a hematoma in the frontal lobe. A new assessment of hemostasis revealed an isolated deficiency of Factor X. We speculate that this deficit could be secondary to consumption due to the chronic Myelomonocytic Leukemia.

The medical records of ten pediatric patients with a clinical diagnosis of tetanus were reviewed retrospectively. The heart rate and blood pressure of all tetanus patients were measured noninvasively every hour during the first two weeks of hospitalization. Six of ten tetanus patients presented clinical evidence of sympathetic hyperactivity (group A) and were compared with a control group consisting of four children who required mechanical ventilation for diseases other than tetanus (group B). Heart rate and blood pressure simultaneously and progressively increased to a maximum by day 7. The increase over baseline was 43.70 ± 11.77 bpm (mean ± SD) for heart rate (P<0.01) and 38.60 ± 26.40 mmHg for blood pressure (P<0.01). These values were higher and significantly different from those of the control group (group B) at day 6, which had an average heart rate increase over baseline of 19.35 ± 12.26 bpm (P<0.05) and blood pressure of 10.24 ± 13.30 mmHg (P<0.05). By the end of the second week of hospitalization, in group A the increase of systolic blood pressure over baseline had diminished to 9.60 ± 15.37 mmHg (P<0.05), but the heart rate continued to be elevated (27.80 ± 33.92 bpm, P = NS), when compared to day 7 maximal values. The dissociation of these two cardiovascular variables at the end of the second week of hospitalization suggests the presence of asymmetric cardiac and vascular sympathetic control. One possible explanation for these observations is a selective and delayed action of tetanus toxin on the inhibitory neurons which control sympathetic outflow to the heart.