Copper microlocalisation and changes in leaf morphology, chloroplast ultrastructure and antioxidative response in white lupin and soybean grown in copper excess

The final publication is available at Springer via http://dx.doi.org/10.1007/s10265-013-0583-1The microlocalisation of Cu was examined in the leaves of white lupin and soybean grown hydroponically in the presence of 1.6 (control) or 192 μM (excess) Cu, along with its effect on leaf morphology, (ultra)structure and the antioxidative response. The 192 μM dose led to a reduction in the total leaf area and leaf thickness in both species, although more strongly so in white lupin. In the latter species it was also associated with smaller spongy parenchyma cells, and smaller spaces between them, while in the soybean it more strongly reduced the size of the palisade parenchyma and epidermal cells. Energy-dispersive X-ray microanalysis showed that under Cu excess the metal was mainly localised inside the spongy parenchyma cells of the white lupin leaves, and in the lower epidermis cell walls in those of the soybean. Cu excess also promoted ultrastructural chloroplast alterations, reducing the photosynthetic capacity index and the green area of the leaves, especially in the soybean. Despite this, soybean appeared to be more tolerant to Cu excess than white lupin, because soybean displayed (1) lower accumulation of Cu in the leaves, (2) enhanced microlocalisation of Cu in the cell walls and (3) greater levels of induced total -SH content and superoxide dismutase and catalase activities that are expected for better antioxidative responsesFunding for this study was provided by the Spanish MCyT (project CTM 2010-21922-C02-02/TECNO), the Autonomous Community of Madrid (project S2009/AMB-1478) and the Junta de Comunidades de Castilla-La Mancha (project POII10-0211-5015

Activity of cefiderocol against high-risk clones of multidrug-resistant Enterobacterales, Acinetobacter baumannii, Pseudomonas aeruginosa and Stenotrophomonas maltophilia

BACKGROUND: Cefiderocol is a novel siderophore cephalosporin, developed for activity against MDR Gram-negative bacilli (MDR-GNB). OBJECTIVES: To assess the in vitro antibacterial activity of cefiderocol against a collection of MDR-GNB clinical isolates from hospitals in southern Spain. METHODS: Two hundred and thirty-one isolates of successful clones were tested: 125 Enterobacterales (121 ESBL- and/or carbapenemase-producing Klebsiella pneumoniae and 4 carbapenemase-producing Enterobacter cloacae), 80 Acinetobacter baumannii, 6 Pseudomonas aeruginosa and 20 Stenotrophomonas maltophilia. Ceftolozane/tazobactam, ceftazidime, ceftazidime/avibactam, cefepime, aztreonam, meropenem, amikacin, ciprofloxacin, colistin and tigecycline were used as comparators against Enterobacterales, P. aeruginosa and A. baumannii. Minocycline, levofloxacin and trimethoprim/sulfamethoxazole were studied against S. maltophilia instead of aztreonam, ciprofloxacin and cefepime. MICs were determined by broth microdilution according to CLSI guidelines. MIC determination was performed in CAMHB for all antimicrobials except cefiderocol, where iron-depleted CAMHB was used. RESULTS: Cefiderocol showed potent in vitro activity against the isolates analysed. MIC50 and MIC90 values were in the ranges 0.125-8 mg/L and 0.5-8 mg/L, respectively, and 98% of isolates were inhibited at ≤4 mg/L. Only five isolates showed cefiderocol MICs of >4 mg/L: three ST2/OXA-24/40-producing A. baumannii, one ST114/VIM-1-producing E. cloacae and one ST114/VIM-1 + OXA-48-producing E. cloacae. All KPC-3-producing K. pneumoniae were susceptible to cefiderocol, even those resistant to ceftazidime/avibactam. P. aeruginosa isolates showed cefiderocol MICs of <4 mg/L, including those resistant to ceftolozane/tazobactam. S. maltophilia isolates displayed cefiderocol MICs of <4 mg/L, including those resistant to levofloxacin and/or trimethoprim/sulfamethoxazole. CONCLUSIONS: Cefiderocol showed excellent activity against MDR-GNB, including carbapenem-resistant isolates, and was the most active antimicrobial tested against this collection

Estudio de la nutrición mineral de Phaseolus Vulgaris L. en suelos de cultivo que contienen metales pesados

9 páginas, ilustraciones y tablas estadísticas. Trabajo presentado en el XI Simposio Ibérico de Nutrición Mineral de las Plantas, celebrado en Pamplona (España), del 19 al 21 de julio de 2006La tala y quema en los bosques tropicales húmedos para usos agrícolas vienen siendo las prácticas más habituales de la población humana ubicada en la provincia de Pedernales República Dominicana, toda ella comprendida en la única Reserva de la Biosfera existente en dicho país, (Hernández et al., 2005, 2006). Estas actividades, unidas a la explotación de la bauxita y de la caliza, conllevan alteraciones en los suelos de los ecosistemas que están siendo utilizados también para la siembra de habichuela (Phaseolus vulgaris L). Esta leguminosa que es originaria de América central (actualmente Latinoamérica aporta una producción del 30% a nivel mundial) tiene bajos rendimientos en el territorio aludido. Por ello este trabajo se ha centrado en conocer los contenidos en nutrientes de esta especie, que constituyen el principal alimento proteínico para la población humana, creciendo en suelos representativos de las características aludidas y que presentan diferentes niveles de metales pesados (Zn, Cu, Cr, Pb, Cd) debido a la litología de los diferentes sustratos.Peer reviewe

Intrathecal cell therapy with autologous stromal cells increases cerebral glucose metabolism and can offer a new approach to the treatment of Alzheimer's type dementia

After recent observations that intrathecal administration of autologous bone marrow mesenchymal stromal cells (MSCs) increases cerebral metabolism in patients with severe traumatic brain injury (TBI), we examined this type of cell therapy in Alzheimer's type dementia. Three patients with clinical diagnosis of Alzheimer's disease received every 3 months 100million autologous MSCs by intrathecal route, until a total dose of 300million. During cell therapy the patients showed arrest in neurological deterioration and two of them manifested clear improvement of previous symptoms. A global increase in cerebral glucose metabolism, measured using 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET), was observed after every administration of cell therapy. Our present findings suggest that intrathecal administrations of autologous MSCs can be a new strategy for the treatment of Alzheimer's dementiaWe thank the institutions supporting the development of our cell therapy program, in particular Mapfre and Rafael del Pino Foundation

Fijación biológica del nitrógeno: factores limitantes

8 páginas y 2 tablasLa Fijación Biológica de Nitrógeno (FBN) representa una alternativa a la fertilización nitrogenada ya que puede paliar muchos de los efectos negativos que dicha fertilización produce tanto a nivel sanitario. La FBN está relegada a organismos procariontes que son capaces de reducir el nitrógeno molecular a amoniaco tanto en vida libre como en simbiosis. La mayor parte del nitrógeno fijado en los ecosistemas terrestres se realiza mediante la asociación simbiótica de bacterias de los géneros Rhizobium, Bradyrhizobium, Sinorhizobium, Azorhizobium y Mesorhizobium (Rhizobium para generalizar) con plantas leguminosas. Gran parte de estas asociaciones simbióticas tiene interés para la Agricultura. Sin embargo, aunque los rendimientos de la FBN se han incrementado considerablemente en los últimos años, al trasladar estos conocimientos a la Agricultura práctica, se detectan limitaciones a la fijación biológica en la simbiosis a nivel medioambiental, biológico, metodológico y a nivel de producción. En este trabajo se analiza el efecto de alguno de estos factores sobre la fijación de nitrógeno y la producción final de grano, desde el punto de vista fisiológico, bioquímico y estructural en la simbiosis Rhizobium-leguminosa.CSIC - Centro de Ciencias Medioambientales (CCMA)Peer reviewe

A Polymer/Oil Based Nanovaccine as a Single-Dose Immunization Approach

The recognized necessity for new antigen delivery carriers with the capacity to boost, modulate and prolong neutralizing immune responses prompted our approach, in which we describe a multifunctional nanocarrier consisting of an oily nanocontainer protected by a polymeric shell made of chitosan (CS), named CS nanocapsules (CSNC). The CS shell can associate the antigen on its surface, whereas the oily core might provide additional immunostimulating properties. In this first characterization of the system, we intended to study the influence of different antigen organizations on the nanocarrier's surface (using the recombinant hepatitis B surface antigen –rHBsAg– as a model antigen) on their long-term immunopotentiating effect, without any additional immunostimulant. Thus, two prototypes of antigen-loaded CSNC (CSNC+ and CSNC−), exhibiting similar particle size (200 nm) and high antigen association efficiency (>80%), were developed with different surface composition (polymer/antigen ratios) and surface charge (positive/negative, respectively). The biological evaluation of these nanovaccines evidenced the superiority of the CSNC+ as compared to CSNC- and alum-rHBsAg in terms of neutralizing antibody responses, following intramuscular vaccination. Moreover, a single dose of CSNC+ led to similar IgG levels to the positive control. The IgG1/IgG2a ratio suggested a mixed Th1/Th2 response elicited by CSNC+, in contrast to the typical Th2-biased response of alum. Finally, CSNC+ could be freeze-dried without altering its physicochemical properties and adjuvant effect in vivo. In conclusion, the evaluation of CSNC+ confirms its interesting features for enhancing, prolonging and modulating the type of immune response against subunit antigens, such as rHBsAgThis work was supported by a grant from the Bill and Melinda Gates Foundation (www.gatesfoundation.org), Consolider Ingenio 2010 CSD2006-00012 (Ministry of Science and Innovation, Spain) and Competitive Reference Groups SUDOE-FEDER (SOE1/P1/E014). SV and MP acknowledge a fellowship from the Spanish Ministry of Education (FPU predoctoral grants). DWP was in part supported by Montana Agricultural Experiment Station and US Department of Agriculture Formula FundsS

Estudio del comportamiento acumulador de Zn en Lupinus albus L., creciendo en suelos ácido y básico contaminados con este metal

4 páginas y tablas estadísticas.Trabajo presentado en el IX Simposio ibérico sobre Nutricion Mineral de las Plantas, celebrado en Zaragoza (España), del 10 al 13 de septiembre de 2002Existen en España numerosas áreas con suelos alterados que corresponden a antiguos vertederos, precariamente sellados, de carácter mixto (con residuos urbanos e industriales). En el centro del país y, concretamente en la Comunidad de Madrid, las cubiertas edáfícas que cubren estos vertederos se encuentran entre los suelos más contaminados de este área peninsular (CAM 1998). Su aprovechamiento actual, pese a su degradación, vuelven a ser actividades agrícolas, y cinegéticas, correspondientes a prácticas habituales del uso tradicional del territorio. Los contaminantes más frecuentes en estos vertederos son diferentes metales pesados, entre los que destaca por su incidencia el Zn seguido del Cu, según puede verse en los estudios citados. Es sabido que distintas especies cultivadas de uso común son extractoras, en mayor o menor grado, de metales pesados cuando crecen en suelos contaminados (Chaney,1989). En el caso de que este hecho se desconozca, puede ser perjudicial para los organismos consumidores de las plantas cultivadas. Sin embargo, esta propiedad extractora constituye una alternativa de empleo respecto a las especies hiperacumuladoras, en razón a su mayor producción de biomasa y a que logran crecer bien y con bajos costes económicos en ambientes donde su uso es habitual y su manejo conocido. En este sentido, el altramuz (Lupinus albus L.), podría ser una planta adecuada para emplearse como extractora de metales pesados de las cubiertas edáfícas de los vertederos. Aquí se sitúa el objetivo de este trabajo. La elección de esta especie se fundamenta en base a diversas características ecofisiologicas que presenta en relación a su adaptabilidad a las condiciones reales que se dan en los vertederos, como son una elevada salinidad, exceso de nitratos y en ocasiones de calcio (Hernández et al., 1998); la capacidad de solubilizar y absorber los elementos del suelo gracias a un potente desarrollo radicular, así como el poseer una importante tolerancia frente a los factores ambientales limitantes señalados (Fernández-Pascual et al, 1996), le hace ser una planta candidata a la fitorremediación de estos sistemas. También se sabe eme los lupinos pueden acumular Mn y Al (Reay and Waugh, 1981) y recientemente se ha visto la acumulación de varios metales (Mn, Cd, Pb, Cr, Hg) en la raíz (Ximénez-Embún et al, 2001). Por ello nos hemos propuesto estudiar su comportamiento frente al Zn en dos tipos de suelos, similares a los empleados en el sellado de los vertederos del sureste de Madrid y en unos niveles de contaminación en línea a la encontrada en vertederos.AMB 1999-1218 (M°CyT)Peer reviewe

Colonisatoin of Pinus halepensis roots by Pseudomonas fluorescens and interaction with the ectomycorrhizal fungus Suillus granulatus

8 pages, figures, and tables statistics.Colonisation of Pinus halepensis roots by GFP-tagged Pseudomonas fluorescens Aur6 was monitored by epifluorescence microscopy and dilution plating. Aur6-GFP was able to colonise and proliferate on P. halepensis roots. Co-inoculation with the ectomycorrhizal fungus Suillus granulatus did not affect the bacterial colonisation pattern whereas it had an effect on bacterial density. Bacterial counts increased during the first 20 days of seedling growth, irrespective of seedlings being mycorrhizal or not. After 40 days, bacterial density significantly decreased and bacteria concentrated on the upper two-thirds of the pine root. The presence of S. granulatus significantly stimulated survival of bacteria in the root elongation zone where fungal colonisation was higher. The number of mycorrhizas formed by S. granulatus was not affected by co-inoculation with Aur6-GFP. Neither Aur6-GFP nor S. granulatus stimulated P. halepensis development when inoculated alone, but a synergistic effect was observed on seedling growth when bacteria and fungus were co-inoculated.Peer reviewe

Spark plasma sintering and optical properties of Tm3+ and Tm3+ /Yb3+ doped NaLaF4 transparent glass-ceramics

Tm3+ doped oxyfluoride glass-ceramics (GCs) containing NaLaF4 nanocrystals (NCs) have been obtained by spark plasma sintering (SPS). First, the precursor glasses were melted and then milled and sieved to a suitable particle size. Glass powder pellets were sintered by spark plasma sintering under vacuum conditions. The SPS processing parameters (temperature, pressure, and holding time) were optimized to obtain transparent glass-ceramics. The times of SPS processing are considerably shorter compared with those for the preparation of these GCs by conventional thermal treatment. All glass-ceramics contain nanocrystals of the β- NaLaF4 phase with an average crystal size of 20 nm, but the more highly doped samples (2Tm3+ and 0.5Tm3+/2Yb3+) show evidence of the presence of another phase corresponding with α-NaLaF4. The luminescence properties of the near infrared (NIR) emissions of Tm3+ for different concentrations reveal the presence of concentration quenching of the 3H4 and 3F4 levels. The analysis of the decay from the 3H4 level with increasing concentration is consistent with a dipole-dipole quenching process assisted by energy migration, whereas the self-quenching of the 3F4→3H6 emission can be attributed to fast diffusion. Energy transfer between Yb3+ and Tm3+ ions is confirmed by the NIR and upconverted (UC) emissions after Yb3+ excitation at 975 nm. No UC emission is observed under 791 nm excitation of Tm3+ ions.Funding from MICINN under project PID2020–115419 GB-C-21/C-22/AEI/10.13039/501100011033 is acknowledged. This paper is part of the dissemination activities of project FunGlass. This project has received funding from the European Union´s Horizon 2020 research and innovation program under grant agreement No 739566

The role of native lichens in the biomonitoring of gaseous mercury at contaminated sites

Contamination by atmospheric mercury has been assessed in two different areas from Spain (Las Cuevas, Ciudad Real and Flix, Tarragona) using lichens as biomonitors. The relationship established between mercury contents in the soils and the gaseous mercury (GM) was also observed. It was found that the GM is highest in the vicinity of the source and it is dispersed depending on of the distance to the source and the wind directions. The mercury concentration in the gas phase in Flix was higher than that found in Las Cuevas and also higher than the value that the US EPA recommended. The mercury bioaccumulation in the native lichens from genders Ramalina and Xanthoria were used as biomonitors for absorbing mercury in Las Cuevas and Flix, respectively. The mercury uptake by Ramalina was higher than the amount accumulated by Xanthoria, a difference that was mainly due to the lichen characteristics. The content of mercury in lichens in relation to the mercury in gas was fitted by a Freundlich type equation, indicating that the equilibrium between both phases was established. Besides, transplanted Ramalina lichen in Las Cuevas allowed to obtain the kinetic of mercury uptake. A kinetic model of first order based on the equilibrium was proposed and the mass transfer constants for each sampling station were estimated. As it was expected, these values increased with the predominant wind flow direction.Se ha evaluado la contaminación por mercurio atmosférico en dos zonas diferentes de España (Las Cuevas, Ciudad Real y Flix, Tarragona) utilizando líquenes como biomonitores. También se observó la relación establecida entre los contenidos de mercurio en los suelos y el mercurio gaseoso (MG). Se comprobó que el MG es más alto en las proximidades de la fuente y se dispersa en función de la distancia a la misma y de las direcciones del viento. La concentración de mercurio en fase gaseosa en Flix fue mayor que la encontrada en Las Cuevas y también mayor que el valor que recomienda la EPA estadounidense. La bioacumulación de mercurio en los líquenes nativos de los géneros Ramalina y Xanthoria se utilizaron como biomonitores de absorción de mercurio en Las Cuevas y Flix, respectivamente. La absorción de mercurio por parte de Ramalina fue mayor que la cantidad acumulada por Xanthoria, diferencia que se debió principalmente a las características del liquen. El contenido de mercurio en los líquenes en relación con el mercurio en el gas se ajustó mediante una ecuación de tipo Freundlich, indicando que se estableció el equilibrio entre ambas fases. Además, el liquen Ramalina trasplantado en Las Cuevas permitió obtener la cinética de captación de mercurio. Se propuso un modelo cinético de primer orden basado en el equilibrio y se estimaron las constantes de transferencia de masa para cada estación de muestreo. Como era de esperar, estos valores aumentaron con la dirección del flujo de viento predominante