Inhibition of LpxC Increases the Activity of Iron Chelators and Gallium Nitrate in Multidrug-Resistant Acinetobacter baumannii

Infections caused by multidrug-resistant Acinetobacter baumannii would benefit from the development of novel treatment approaches. Compounds that interfere with bacterial iron metabolism, such as iron chelators and gallium nitrate, have previously been shown to have antimicrobial activity against A. baumannii. In this study, we characterize the effect of LpxC inhibitors on the antimicrobial activity of previously characterized iron chelators, 2,2'-bipyridyl (BIP) and deferiprone (DFP), and gallium nitrate (Ga(NO3)3) against A. baumannii reference strains and multidrug-resistant clinical isolates. The LpxC inhibitor LpxC-2 was synergistic with BIP for 30% of strains tested (FICI values: 0.38-1.02), whereas inhibition with LpxC-4 was synergistic with BIP for 60% of strains tested (FICI values: 0.09-0.75). In time-kill assays, combinations of BIP with both LpxC inhibitors demonstrated synergistic activity, with a more than 3 log10 reduction in bacterial counts compared to BIP alone. LpxC-2 was synergistic with Ga(NO3)3 for 50% of strains tested (FICI values: 0.27-1.0), whereas LpxC-4 was synergistic with Ga(NO3)3 for all strains tested (FICI values: 0.08-≤0.50). In time-kill assays, combinations of Ga(NO3)3 with LpxC-2 and LpxC-4 decreased the growth of both strains compared to each compound separately; however, only the combination with LpxC-4 met the defined criteria for synergy. These results identify a novel synergy between two antimicrobial classes against A. baumannii strains.This research was supported by grants MPY 380/18 from the Instituto de Salud Carlos III (ISCIII) awarded to M.J.M. V.V. is supported by the Río Hortega Program from the Instituto de Salud Carlos III. The APC was funded by MPY 380/18 from the Instituto de Salud Carlos III (ISCIII) awarded to M.J.M.S

Levels of Physical Activity during School Hours in Children and Adolescents: A Systematic Review

Background: This systematic reviewdetermines the levels of physical activity (PA) during school hours in children and adolescents.Methods: Studies carried out fromJanuary 1987 toDecember 2019were retrieved from four databases (Web of Science, Pubmed, Scopus and SportDiscus). Results: Twenty-nine studies were included in this systematic review. Most of them used accelerometers and showed that male and female children accumulated a mean of between 14 and 68 min of moderate-to-vigorous PA (MVPA) during school hours (3–22% of this daily segment), andmale and female adolescents accumulated amean of between 13 and 28min ofMVPA during this daily segment (3–8% of the school hours). Less than a quarter of children and adolescents reached the recommended 30 min of MVPA during school hours, with notable differences between sexes. Conclusions: These results suggest that the levels of PA during school hours are not enough, and consequently, schools should develop strategies for helping children and adolescents reach the school PA recommendation

Beatriz Galindo : fortuna y poder de una humanista en la corte de los Reyes Católicos

La vida y la muerte están unidas en un testamento, a través de este documento –que es un expediente formado por distintos documentos- podemos estudiar la forma de vida y los ingresos de un matrimonio que representa muchos de los aspectos de la Corte de los Reyes Católicos: Francisco Ramírez de Madrid y Beatriz Galindo. Éstos asentaron una parte importante de su fortuna en el Reino de Granada y en la ciudad de Málaga. Este documento también permite conocer cómo la viuda, Beatriz Galindo, pudo apelar a los reyes porque estaba en desacuerdo con la última voluntad de Francisco Ramírez de Madrid.Life and death are linked in a testament, through this document –that is a file of different records- we can study the way of life and the incomes of a couple that represented many aspects of the Court of the Catholic Kings: Francisco Ramírez de Madrid and Beatriz Galindo. They settled an important part of they fortune in the Kingdom of Granada and in the city of Malaga. This record also allows to know how the widow, Beatriz Galindo, could appealed the King and Queen because she was in disagreement with the last wish of Francisco Ramírez de Madrid

Modelo bidimensional de transmisión de calor en tableros de puente

The thermal effects on bridge decks has been a siibject of iilt,erest during the last two decades, beginning the analysis of heat conduction in the deck and the thermal conditions which deal with it. The numerical handling of the problem had been reduced up to the present time, to one-dimensional models of lieat transmission, which can only represent reasonably slab decks, mainly in llie central area. Altliough, tlie most important effects produced by thermal gradients are located in selections with thin walls and in the borders of the deck. The authors have developed a two-dimensional model of lieat conduction that reproduce the temperature field in a complete section of tlie bridge in a realistic manner

Improvements to the X-ray Spectrometer at the Aerosol Laboratory, Instituto de Física, UNAM

Due to the demands of better (accurate and precise) analytical results using X-ray Fluorescence (XRF) at the Aerosol Laboratory, Instituto de Física, UNAM, it was necessary to carry out improvements in instrumentation and analytical procedures in the x-ray spectrometer located in this facility. A new turbomolecular vacuum system was installed, which allows reaching the working pressure in a shorter time. Characteristic x-rays are registered with a Silicon Drift Detector, or SDD, (8 mm thick Be window, 140 eV at 5.9 keV resolution), working directly in a high-vacuum, permitting the detection of x-rays with energies as low as 1 keV (Na Ka) and higher counting rates than in the past. Due to the interference produced by the Rh L x-rays emitted by the tube normally used for atmospheric and food analysis with Cl K x-rays, another tube with a W anode was mounted in the spectrometer to avoid this interference, with the possibility to select operation with any of these tubes. Examples of applications in atmospheric aerosols and other samples are presented, to demonstrate the enhanced function of the spectrometer. Other future modifications are also explained

Determinación experimental de la carga de apertura de grieta en fatiga bajo cargas aleatorias

El concepto de carga de apertura o cierre de grieta es ampliamente utilizado en fatiga para justificar el comportamiento del crecimiento de grietas con distintas relaciones de carga y el efecto de interacción de las cargas. Hasta la fecha son numerosas las técnicas experimentales propuestas para medir la apertura de grieta y entre ellas los métodos de flexibilidad son ampliamente utilizados por su simplicidad. En este trabajo se propone una modificación del método propuesto por la ASTM y se presentan los resultados obtenidos en ensayos de crecimiento de grietas por fatiga bajo cargas aleatorias. Así mismo, los valores experimentales de cargas de apertura son comparados con los calculados analíticamente por un modelo de simulación tipo “strip-yield” implementado en el software NASGRO. En general, se ha encontrado una concordancia razonablemente buena entre los valores experimentales y los obtenidos por simulación.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Los autores agradecen la financiación aportada para la realización de este trabajo al Ministerio de Economía y Competitividad (referencia MAT2016-76951-C2-2-P)

Anthropogenic influence in the Sado estuary (Portugal): a geochemical approach

Two areas of salt marsh in the Sado estuary – Faralhão, on the industrialized north margin and Malha da Costa, on the south bank, sheltered by a uninhabited sand spit – have been cored to study the geochemical signature of anthropogenic activity in recent (19th century onwards) intertidal sediments. Short cores were taken from each site from both the high and low marsh and were studied for texture, organic matter, pH, carbonates and geochemistry, including the heavy metals Cu, Pb and Zn. The marsh sediments are free of carbonate bioclasts and quite uniform in texture, consisting of acid to neutral clayey silt in addition to organic matter, which is higher in the top 20 cm. The vertical concentration profiles of heavy metals indicates enrichment in the top 30 cm of the sediment of the high marsh, in contrast with underlying high and low marsh sediment that has concentrations of metals at both studied sites similar to the Average Shale international reference/ continental crust sediments. The geochemical signal of anthropogenic influence in the marsh sediment was determined to have commenced from 1900-1920 using the sedimentation rates derived from 210Pb and 137Cs analyses. Spatial contrast in contamination levels was found within the estuary, with sediments of the Faralhão marsh showing higher enrichment factors of all metals. The anthropogenic increase of the supply of metal to the Sado estuary resulted from extensive exploitation of pyrite ore in the drainage basin until the1960’s; since that time, the sediments record a break in metal input, which resulted from a decline of the mining industry. However, in the marsh located closer to the industrial area (Faralhão) this break is followed by a local increase of heavy metal fluxes, which is interpreted as the result of intensification of anthropogenic influence. The comparison of metal concentrations in marsh sediments with target values established in quality guidelines indicates the studied area to be of environmental concern.Con el fin de estudiar el registro geoquímico de la actividad antrópica en sedimentos recientes (a partir del siglo XIX) e intermareales, han sido perforadas dos zonas de marisma en el Estuario del Sado- Faralhão, en el industrializado margen norte, y Malha da Costa, en la orilla sur, resguardada por una flecha litoral de arena no ocupada antrópicamente. Los pequeños sondeos realizados en cada punto de muestreo englobaron la marisma alta y baja. Fueron realizados análisis texturales, de contenido en materia orgánica, de pH, carbonatos y geoquímica, incluyendo los metales pesados Cu, Pb y Zn. Los sedimentos de marisma no muestran carbonato bioclástico y son bastante uniformes en la textura, consistiendo en limo arcilloso ácido a neutro junto con materia orgánica cuyo contenido es mayor en los 20 cm más superficiales. La concentración vertical de los perfiles de metales pesados indica un enriquecimiento en los 30 cm superficiales de la marisma alta, en contraste con los sedimentos subyacentes de marisma alta y baja que poseen concentraciones de metales similares a los referenciados internacionalmente para Average Shale / sedimentos de corteza continental. La señal geoquímica de la influencia antrópica en los sedimentos de marisma fue datada de 1900 a 1920 usando las tasas de sedimentación deducidas mediante 210Pb y 137Cs. Un contraste espacial en los niveles de contaminación fue encontrado en el interior del estuario: la marisma de Faralhão muestra valores con mayor enriquecimiento para todos los metales. El aporte antrópico de metales en el estuario de Sado resulta de la extensa explotación de pirita en la cuenca hasta 1960; a partir de ese momento los sedimentos registran una disminución en el aporte antropogénico de metales, consecuencia de la disminución del trabajo minero. Sin embargo, en la marisma cercana a la zona industrial (Faralhão) a esta interrupción le sigue un restablecimiento del flujo de metales pesados, interpretado como resultado del aumento de la influencia antrópica. La comparación de las concentraciones de metales en sedimentos de marisma con valores fijados establecidos en directrices de calidad sugiere una inquietud ambiental para el área de estudio

Delayed development of basal spikelets in wheat explains their increased floret abortion and rudimentary nature

Large differences exist in the number of grains per spikelet across an individual wheat (Triticum aestivum L.) spike. The central spikelets produce the highest number of grains, while apical and basal spikelets are less productive, and the most basal spikelets are commonly only developed in rudimentary form. Basal spikelets are delayed in initiation, yet they continue to develop and produce florets. The precise timing or the cause of their abortion remains largely unknown. Here, we investigated the underlying causes of basal spikelet abortion using shading applications in the field. We found that basal spikelet abortion is likely to be the consequence of complete floret abortion, as both occur concurrently and have the same response to shading treatments. We detected no differences in assimilate availability across the spike. Instead, we show that the reduced developmental age of basal florets pre-anthesis is strongly associated with their increased abortion. Using the developmental age pre-abortion, we were able to predict final grain set per spikelet across the spike, alongside the characteristic gradient in the number of grains from basal to central spikelets. Future efforts to improve spikelet homogeneity across the spike could thus focus on improving basal spikelet establishment and increasing floret development rates pre-abortion