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Monolayers of 1,2-dipalmitoyl-sn-glycero-3-cytidine were incubated with guanine in a 0.1 M NaF electrolyte at the surface of a Langmuir trough and transferred to gold (111) electrodes using the Langmuir–Schaefer technique. Chronocoulometry and photon polarization modulation infrared reflection absorption spectroscopy were employed to investigate the influence of the static electric field on the orientation and conformation of the cytidine nucleolipid molecules on the metal surface in the presence of guanine and to monitor the molecular recognition of guanine with the cytosine moiety. When the monolayer is exposed to guanine solutions, the cytosine moiety binds to the guanine residue in either a Watson–Crick complex at positively charged electrode surfaces or a noncomplexed state at negative surface charges. The positive electrostatic field causes the cytosine moiety and the cytosine–guanine complex to adopt a nearly parallel orientation with respect to the plane of the monolayer with a measured tilt angle of ∼10°. The parallel orientation is stabilized by the interactions between the permanent dipole of the cytosine moiety or the Watson–Crick complex and the static electric field. At negative charge densities, the tilt of the cytosine moiety increases by ∼15–20°, destabilizing the complex. Our results demonstrate that the static electric field has an influence on the molecular recognition reactions between nucleoside base pairs at the metal–solution interface and can be controlled by altering the surface charge at the metal. Spanish Ministry of Economy and Competitiveness and Andalusian government, Natural Sciences and Engineering Council of Canada (NSERC)

The effect of the electrode potential on the orientation and conformation of the 1,2-dipalmitoyl-sn-glycero-3-cytidine monolayer deposited on a gold (111) electrode surface was described. The potential of zero free charge (Epzc) for the monolayer-covered electrode was determined to be −0.2 V vs SCE. The differential capacitance and charge density data indicated that the monolayer is stable at the electrode surface when (E – Epzc) > 0.0 V. At negative rational potentials, a progressive detachment (electrodewetting) of the monolayer occurs. The monolayer is fully detached from the electrode surface at (E – Epzc) < −0.6 V. The conformation and orientation of the acyl chains and the orientation of the cytosine moiety were determined with the help of photon polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS). The IR measurements demonstrate that the acyl chains are predominantly in the gel phase in the adsorbed state and tilted at an angle of ∼30° with respect to the electrode surface normal. The tilt angle of the acyl chains increases when the film is detached from the gold surface, indicating that the monolayer becomes more disordered. At (E – Epzc) > 0.0 V, the plane of the cytosine moiety assumes a small angle of ∼20° with respect to the surface. At negative potentials, the tilt angle of the cytosine fragment increases and rotates. With the help of DFT calculations, these changes were explained by the repulsion of the positive pole of the cytosine permanent dipole moment by the positively charged gold surface and its attraction to the metal surface at negative electrode potentials. This work provides unique information for the future development of sensors based on the molecular recognition of nucleoside targets. Spanish Ministry of Economy and Competitiveness and the Andalusian government, Spanish Ministry of Science and Technology. Natural Sciences and Engineering Council of Canada (NSERC)

Objectives: Incomplete or ambiguous evidence for identifying high-risk patients with acute respiratory distress syndrome for enrollment into randomized controlled trials has come at the cost of an unreasonable number of negative trials. We examined a set of selected variables early in acute respiratory distress syndrome to determine accurate prognostic predictors for selecting high-risk patients for randomized controlled trials. Design: A training and testing study using a secondary analysis of data from four prospective, multicenter, observational studies. Setting: A network of multidisciplinary ICUs. Patients: We studied 1,200 patients with moderate-to-severe acute respiratory distress syndrome managed with lung-protective ventilation. Interventions: None. Measurements and Main Results: We evaluated different thresholds for patient's age, Pao 2 /Fio 2, plateau pressure, and number of extrapulmonary organ failures to predict ICU outcome at 24 hours of acute respiratory distress syndrome diagnosis. We generated 1,000 random scenarios as training (n = 900, 75% of population) and testing (n = 300, 25% of population) datasets and averaged the logistic coefficients for each scenario. Thresholds for age (< 50, 50-70, > 70 yr), Pao 2 /Fio 2 (= 100, 101-150, > 150 mm Hg), plateau pressure (< 29, 29-30, > 30 cm H2O), and number of extrapulmonary organ failure (< 2, 2, > 2) stratified accurately acute respiratory distress syndrome patients into categories of risk. The model that included all four variables proved best to identify patients with the highest or lowest risk of death (area under the receiver operating characteristic curve, 0.86; 95% CI, 0.84-0.88). Decision tree analyses confirmed the accuracy and robustness of this enrichment model. Conclusions: Combined thresholds for patient's age, Pao 2 / Fio 2, plateau pressure, and extrapulmonary organ failure provides prognostic enrichment accuracy for stratifying and selecting acute respiratory distress syndrome patients for randomized controlled trials.

Clinical and molecular studies are reported on a Basque family (MRX82) with nonsyndromic X-linked mental retardation (XLMR) in five affected males. A total of 38 microsatellite markers were typed. The XLMR locus has been linked to DXS8067, DXS1001, DXS425, DXS7877, and DXS1183 with a maximum LOD score of 2.4. The haplotype studies and multipoint linkage analysis suggest a localization of the MRX82 locus to an interval of 7.6 Mb defined by markers DXS6805 and DXS7346, in Xq24 and Xq25, respectively. No gene contained in this interval has been so far associated with nonsyndromic mental retardation, except for GRIA3, disrupted by a balanced translocation in a female patient with bipolar affective disorder and mental retardation. However, the search for mutations of this gene did not showed a pathogenic mutation in the present family. Given that there are other eight MRX families overlapping this interval, none of them with known mutation, we conclude that at least one new gene responsible for nonsyndromic mental retardation is located in this region.

Actualmente, la cosecha de café en Colombia se realiza de manera manual, tiene un alto requerimiento de mano de obra y es responsable del 40% de los costos de producción. Para determinar las necesidades de mano de obra, los productores realizan estimaciones de la producción mediante métodos destructivos o subjetivos. Este trabajo investiga el desarrollo de una estrategia, basada en el análisis de imágenes, para planificar la cosecha del café a través de la estimación no destructiva del porcentaje de frutos maduros (PM) en las ramas. Para la puesta a punto de la metodología, se adquirieron imágenes utilizando un teléfono móvil en diferentes condiciones de campo a un total de 69 ramas de café variedad Castillo®, con un PM entre el 10% y el 70%. Debido a la longitud de las ramas (entre 40 y 60 cm), se capturaron varias imágenes de cada rama, obteniendo un total de 280 imágenes. Para segmentar las imágenes se utilizó la aplicación Food-ColorInspector (http://www.cofilab.com) y para cada rama se obtuvo mediante esta aplicación el área correspondiente a tres estados de madurez de los frutos (inmaduro, semimaduro y maduro), que se asoció al PM. Adicionalmente, se realizó el conteo manual de los frutos en los distintos estados de maduración. Se utilizaron 23 ramas escogidas al azar para crear un modelo lineal de estimación entre los porcentajes de madurez obtenidos mediante el análisis de las imágenes y el análisis manual. El modelo obtuvo un coeficiente de determinación R2=88%, con un error promedio absoluto del 3,9% entre el PM estimado a mano y mediante análisis de imagen. Posteriormente, este modelo se validó con 46 ramas restantes, obteniendo un R2=75% y un error promedio de 5,5%. Los resultados son prometedores para la creación de herramientas que automaticen la actual estimación manual de cosecha del café mediante el uso dispositivos móviles, como teléfonos inteligentes, al alcance de cualquier caficultor

El término humanismo arranca de la antigüedad clásica. Cinco siglos antes de la era cristiana, los sofistas, desde su posición de educadolores de una pequeña minoría, dieron validez a un concepto que con el transcurso de los siglos y en presencia de cambiantes realidades históricas se iría llenando de nuevo contenido. Heráclito, al hacer la articulación del hombre en la constitución legal de Cosmos, regido por un principio unitario, según señaló W. Jaeger, contribuyó de manera decisiva a acuñar una nueva teoría educativa. Con los sofistas se inicia una etapa de gran importancia en el desarollo del humanismo, al cual define dicho autor "como la idea de la formación humana" que se emparenta con la lla.mada educación "general" humana, que tiene en Grecia también su origen (1).

Los pacientes con insuficiencia renal crónica presentan un marcado descenso de la tasa de filtración glomerular por lo que requieren de terapia de reemplazo renal como la diálisis o el trasplante para sobrevivir. El objetivo del estudio fue determinar las características de los pacientes en lista de espera para trasplante renal. Analizamos 156 pacientes provenientes de diversos centros de diálisis que acudieron al Laboratorio Central de Salud Pública entre julio de 2.013 y agosto de 2.014. Se recolectaron datos demográficos y muestras de sangre para determinar la presencia de anticuerpos anti-HLA por ELISA. Las edades estaban comprendidas entre 4 y 74 años, con un promedio de 40 años. Se registraron pacientes de 15 de las 18 Regiones Sanitarias del país, 50% de los cuales provenían de Asunción y del Departamento Central. La cobertura médica se encontró dividida en partes iguales entre el Ministerio de Salud Pública y el Instituto de Previsión Social. El tiempo promedio en diálisis fue de 34 meses, el 66% de los pacientes fueron poli-transfundidos, el 13% candidatos a retrasplante y el 34% de las mujeres fueron multíparas. El 36% de la población estudiada presentó anticuerpos anti-HLA. Se concluye que los pacientes en espera de trasplante renal se caracterizan por encontrarse en plena edad productiva y por permanecer en diálisis durante varios años. Además, un tercio de esta población se encuentra inmunizada frente a antígenos de histocompatibilidad, lo que dificulta su acceso al trasplante. Patients with chronic renal failure present a pronounced reduction of the glomerular filtration rate and therefore, require renal replacement therapy such as dialysis or kidney transplantation to survive. The aim of this study was to determine the characteristics of patients on the waiting list for kidney transplantation. We analyzed 156 patients from various dialysis centers who came to the Central Laboratory of Public Health between July, 2013 and August, 2014. Demographic information and blood samples were collected to determine the presence of anti-HLA antibodies by ELISA. Ages were between 4 and 74 years, with a mean of 40 years. There were patients from 15 of the 18 health regions of the country, 50% of them came from Asunción and the Central Department. Medical coverage was found to be divided in equal parts between the Ministry of Public Health and the Social Security Institute. The mean time on dialysis was 34 months, 66% of the patients had received multiple blood transfusions, 13% of them were candidates for a second transplant, and 34% of the women were multiparous. Thirty six percent of the studied population presented anti-HLA antibodies. The results of this study indicate that patients awaiting kidney transplantation in Paraguay are characterized by being at their productive age and remain on dialysis for several years. In addition, a third of this population is immunized against histocompatibility antigens, which hinders their access to transplantation.