Atomic-level characterization and cilostazol affinity of poly(lactic acid) nanoparticles conjugated with differentially charged hydrophilic molecules

Indexación: Scopus.M.F.M. acknowledges support from CONICYT-PFCHA/Doctorado Nacional/2014-21140225. M.M.M. thanks the FONCyT PICT-2015-2191, CONICET PIP 11220110100992, Secyt, Universidad Nacional de Cordoba. C.V. acknowledges support from CONICYT under FONDECYT #1161438 and BASAL Grant FB0807, MECESUP PMI-UAB1301, and H2020-MSCA-RISE-2016 #734801 MAGNAMED. The authors thank the High-Performance Computational Center (CCAD UNC) and Escuela de Ingeniería Civil en Bioinformática (Universidad de Talca) for access to supercomputers.Nanotherapeutics is a promising field for numerous diseases and represents the forefront of modern medicine. In the present work, full atomistic computer simulations were applied to study poly(lactic acid) (PLA) nanoparticles conjugated with polyethylene glycol (PEG). The formation of this complex system was simulated using the reactive polarizable force field (ReaxFF). A full picture of the morphology, charge and functional group distribution is given. We found that all terminal groups (carboxylic acid, methoxy and amino) are randomly distributed at the surface of the nanoparticles. The surface design of NPs requires that the charged groups must surround the surface region for an optimal functionalization/charge distribution, which is a key factor in determining physicochemical interactions with different biological molecules inside the organism. Another important point that was investigated was the encapsulation of drugs in these nanocarriers and the prediction of the polymer-drug interactions, which provided a better insight into structural features that could affect the effectiveness of drug loading. We employed blind docking to predict NP-drug affinity testing on an antiaggregant compound, cilostazol. The results suggest that the combination of molecular dynam ics ReaxFF simulations and blind docking techniques can be used as an explorative tool prior to experiments, which is useful for rational design of new drug delivery systems. © 2018 Matus et al.https://www.beilstein-journals.org/bjnano/articles/9/12

Diversity of N2-fixing cyanobacteria from Andalusian paddy fields and analysis of their potential as bioinoculants

The marshes of the Guadalquivir River contain the largest area of rice cultivation in Spain, where more than 40,000 ha are used every year for rice production. These wetland areas provide a perfect place for rice cultivation, and represent a unique aquaticterrestrial habitat that hold more wintering waterfowl than any other European wetland. Paddies require large amounts nitrogen and phosphorus for their growth, development and production. Though, flooded conditions used for rice cultivation drastically diminish efficiency inorganic nitrogen fertilizers, being only 30–40% used by the plant, and in some cases even less. Large amounts of nitrogen fertilizers are dissolved in the surface water and lost, causing environmental pollution and health problems due to losses through N2O and NO volatilization, denitrification, and leaching (Ishii et al., 2011)

La fijación externa monolateral en el tratamiento de las fracturas femorales del niño: experiencia preliminar en 20 casos

Veinte niños con fracturas femorales diafisarias simples fueron tratados mediante fijación externa con el aparato de Wagner. Once eran niños y 9 niñas, con una edad media de 8 años (3-15). Doce fracturas eran mediodiafisarias, 6 en el tercio proximal y 2 en el tercio distal. La hospitalización media fue de 9 días (5-20). La duración media de fijación externa fue de 61 días. Cinco casos precisaron de algún tratamiento adicional. En 3 pacientes se detectó una infección en el trayecto de los clavos y 1 de ellos necesitó retirada prematura del aparato. La movilidad articular de la rodilla se restableció de modo completo y constante excepto en 1 caso. En los casos seguidos más de 18 meses se observó un hipercrecimiento medio del fémur fracturado de 0,8 cm (0,5- 1,5). No hubo desaxaciones ni malrotaciones. Las ventajas de la fijación externa en el tratamiento de las fracturas femorales del niño incluyen Un mejor control de los fragmentos fracturarlos, una menor hospitalización y un cuidado más fácil y confortable de los pacientes. La infección del trayecto de los clavos parece ser la complicación más seria. En esta serie se detectó una curva de aprendizaje.Twenty children with simple femoral-shaft fractures were treated by monolateral external fixation with the Wagner device. There were 11 boys and 9 girls with a mean age of 8 years (3-15). Twelve fractures were located at the midshaft, 6 at the proximal third, and 2 other at the distal third of the femur. The mean hospital stay was 9 days (5-20). Mean external fixation time was 61 years. In 5 cases, additional methods of treatment were required. Pin tract infection occurred in 3 cases (one needed premature removal of the device). Except for one case, full range of knee motion was usually achieved after treatment. In patients followed for more than 18 months, a mean femoral overgrowth of 0.8 cm (0.5-1.5) was detected. Neither angular deformities nor malrotations were observed. In our experience, the main advantages of external fixation for femoral-shaft fractures in children include less hospitalization time and an easier and more confortable nursing. External fixation allows a better control of the bone fragments, providing an adequate stability. Pin tract infection seems to be the most important drawback. A learning curve was observed in this series

Diversity of N2-fixing cyanobacteria from Andalusian paddy fields and analysis of their potential as bioinoculants

The marshes of the Guadalquivir River contain the largest area of rice cultivation in Spain, where more than 40,000 ha are used every year for rice production. These wetland areas provide a perfect place for rice cultivation, and represent a unique aquatic-terrestrial habitat that hold more wintering waterfowl than any other European wetland.Paddies require large amounts nitrogen and phosphorus for their growth, development and production. Though, flooded conditions used for rice cultivation drastically diminish efficiency inorganic nitrogen fertilizers, being only 30–40% used by the plant, and in some cases even less. Large amounts of nitrogen fertilizers are dissolved in the surface water and lost, causing environmental pollution and health problems due to losses through N2O and NO volatilization, denitrification, and leaching (Ishii et al., 2011).The paddy field ecosystem provides a favourable environment for the growth of phototrophic microorganisms including nitrogen-fixing cyanobacteria, as it meets their requirements for light, water, temperature and nutrient availability. The ability of this type of cyanobacteria to fix N2 provides a natural source of fixed nitrogen to the plant that is evidently priceless, and encourages research to develop new cyanobacteria-based biofertilizers for rice cultivation. In our laboratory, diversity of N2-fixing cyanobacteria from Andalusian paddies has been studied by means of metagenomic analysis and classical microbiological approaches. We have found that agronomic techniques influence microbial diversity (Ramírez-Moncayo et al., 2018). We have also isolated Nitrogen-fixing cyanobacteria from the paddy fields and we have found that Nostocaceae and Rivulariaceae are the dominant N2-fixing cyanobacteria families in these isolates (Alves-Martínez et al., 2017). Genetic analysis of the different isolates revealed the presence of new uncharacterized strains. We have evaluated their potential as bioinoculants for plant fortification. Some of the strains showed a strong attraction and attachment to rice roots, which could be an indication of possible supply to the plant of nitrogen-fixed metabolites by the cyanobacterium. These isolates might be used for the formulation of new ecological biofertilizers alternative to chemical synthetic fertilizers

Music distraction among young drivers: analysis by gender and experience

The aim of this study was to quantify the probability of committing a speed infraction by young drivers and to investigate to what extent listening music could affect young drivers’ emotions as well as their driving performances at the wheel. To achieve this aim, employing Bayesian networks, the study analysed different music styles, in which they resulted in sample drivers’ speed infractions. Gender and drivers’ experiences at the wheel were the other factors, which were taken into account when interpreting the study results. Variables taken into account in this study included type of music whilst driving, gender of drivers, and drivers’ driving experiences. These variables further incorporated into the study of other telemetric variables including acceleration, number of revolutions per minute (RPM) of the engine, brake, traffic, and other types of infractions other than speed, which were considered as dependent variables. A driving simulator was used, and different driving simulation studies were carried out with young people aged between 20 and 28 years. Each participant carried out three simulations by listening to different type of music in each journey. The study defined a conceptual model in which the data were analysed and evaluated mathematically through Bayesian networks. A sensitivity analysis was performed to evaluate the influence of music on driving speed. Based on the different variables, the study further analysed the probability of speed infractions committed by drivers and their adequate speed. The range of frequency probabilities varied between 96.32% (which corresponds to experienced male drivers who do not listen to music) and 79.38% (which corresponds to less-experienced female drivers who listen to music), which resulted in their happiness or aggression.FEDER (Fondo Europeo de Desarrollo Regional) for developing Castilla y Le´on´s region. *e title of the project is “Modelizaci´on mediante t´ecnicas de machine learning de la influencia de las distracciones del conductor en la seguridad vial-Modeling the influence of driver´s distractions on road safety through machine learning techniques.” Ref. BU300P1

Detección de indicadores de contaminación fecal y pseudomonas en muestras de agua cruda y tratada de las plantas potabilizadoras de Chilibre y Miraflores de Panamá

Es importante establecer modelos de evaluación y gestión integral que garanticen la calidad del suministro de agua. Es por esto, que el uso de microorganismos bioindicadores de calidad del agua, disminuye los costos y facilita la implementación de medidas eficientes de tratamiento, control del agua y de enfermedades asociadas a su transmisión. Debido a esto, el objetivo de este estudio es evaluar la presencia de bacterias coliformes y Pseudomonas en muestras de agua cruda y tratada de las plantas potabilizadoras de Chilibre y Miraflores de la Ciudad de Panamá. Se llevaron a cabo dos muestreos por semana con tres repeticiones por cada punto de muestreo, siendo 6 muestras de agua cruda y tratada para cada potabilizadora por 12 semanas desde octubre a diciembre de 2019. Las muestras de agua cruda y tratada de la planta potabilizadora de Chilibre fueron recolectadas dentro de la planta y en el caso de la potabilizadora de Miraflores, el agua cruda fue recolectada en una zona abierta dentro del Lago Gatún y el agua tratada fue recolectada a través de las redes de distribución, en el centro de salud de Paraíso, corregimiento de Ancón. Estas muestras fueron transportadas en cadena de frío a los laboratorios de la Universidad de Panamá y procesadas mediante la técnica de filtro de membrana con medios de cultivos para coliformes termotolerantes fecales y totales, Pseudomonas y recuento total de heterótrofos. Con los resultados de estos análisis, se pudo demostrar que existen diferencias significativas entre el recuento total por tipo de microorganismos, tipo de agua y tipo de potabilizadora (Friedman chi-cuadrado = 353.77, df = 2, p-value < 2.2e16). Además, se observó una disminución significativa durante el proceso de potabilización del agua de los niveles de coliformes termotolerantes y totales en agua potable en ambas potabilizadoras, de acuerdo con la norma DGNTI-COPANIT 21-2019, encontrándose dentro de los valores permitidos que son establecidos para el agua para consumo humano. Esto determina el buen nivel de desinfección de ambas potabilizadoras

Identificação de deficiências minerais de bovinos na microrregião Alto Purus-Acre.

A Unidade de Execução de Pesquisa de Âmbito Estadual - UEPAE/Rio Branco, vem desenvolvendo estudos com os objetivos de identificar as deficiências minerais de bovinos na microrregião Alto Purus-Acre, determinando as interrelações entre os níveis de minerais no solo, nas forrageiras e nos tecidos animais durante as estações chuvosa e seca.bitstream/item/145816/1/1097.pd

Vortex solitons of the discrete Ginzburg-Landau Equation

We have found several families of vortex soliton solutions in two-dimensional discrete dissipative systems governed by the cubic-quintic complex Ginzburg-Landau equation. There are symmetric and asymmetric solutions, and some of them have simultaneously two different topological charges. Their regions of existence and stability are determined. Additionally, we have analyzed the relation- ship between dissipation and stability for a number of solutions. We have obtained that dissipation favours the stability of the solutions.Comment: 7 pages, 11 figure