81 research outputs found
Estudio de algunos haploxerolles de la provincia de Murcia
This paper gives account of the results obtained on the macromorphological, analytical and rninerailogical study of three representative HAPLOXEROLLS from the province of Murcia (Spain). They show an A-B-C profile, with an A horizon reaching 40-50 cm in depth, and enough organic matter content to be a moUic epipedon. Taking into account the variations of the organic mater and equivalen calcium carbonate contents with depth, the fluventic characteristics of the profile are evidents. Calcareous from the surface, these soiis are saturated, being calcium the dominant exchangeáble catión. The heavy mineral fraction from the fine sand is made up by resistant minerals with tourmaline as the main component, making up several associations with other minerals. The clay fraction shows a rather complex mineralogical composition, with illite and caolinite as the main components and vermiculite, chlorite, smectites, quartz and athapulgite in minor amounts.En el presente trabajo se da cuenta del estudio macromorfalógico, analítico y mineralógico de tres perfiles de suelos representativos de HAPLOXEROLLES de la provincia de Murcia. Se trata de suelos con perfil A-B-C, en los que el horizonte A alcanza profundidades de 40 a 50 cm o más, con contenidos en materia orgánica suficientes para ser epipedon móllico, y se ponen en evidencia las características fluvénticas de los perfiles, dadas las variaciones que sufren en profundidad tanto los contenidos en materia orgánica como en carbonato calcico equivalente. Calizos desde la superficie, son suelos totalmente saturados en bases, siendo el calcio el catión dominante en el complejo de cambio. La fracción pesada de Ja arena fina está constituida por minerales resistentes entre los que predomina la turmalina, que forma diversas asociaciones con otros minerales. La fracción arcilla posee una composición mineralógica bastante compleja, con ilita, caolinita, vermicuilita, clorita, smectitas, cuarzo y en ocasiones atapulgita, pero, en general, es bastante similar en los distintos perfiles estudiados
Assessment of the mobility of metals in a mining-impacted coastal area (Spain, Western Mediterranean)
A study on metal mobilisation (Zn, Pb and As) from contaminated sediments in Portman Bay (SE Spain) was carried out. Thisarea has suffered a major impact from mining activity, as millions of tons of mine tailings have been dumped into the bay over a long period, gradually filling the bay. A three-step sequential extraction procedure, modified from the BCR (Community Bureau of Reference) method, as well as selective extractions (H2O, 0.1 N HNO3, citrate–dithionite and 1 M NH4OAc after H2O2 attack) were applied to selected samples in order to evaluate the potential mobility of fixed metals. Acid volatile sulfides (AVS) and simultaneously extracted metals (SEM) were also determined. X-ray diffraction (XRD) and scanning electron microscopy coupled to with an energy-dispersion spectrometry (SEM-EDS) were applied to the characterization of both raw samples and the residues remaining after each extraction, providing additional information about the sediment phases carrying the metals studied. Metals associated with sediments showed different behaviour depending on the mineralogical phase they were bound to. Zn was the most labile metal, while Pb and As showed a lower mobility. The fraction of metals associated with jarosites presented a high stability under different physicochemical conditions, while metals associated with mineralogical phases that are undergoing supergenic alteration processes presented a high mobility. The results obtained may be useful to assess both the short and the long-term environmental impact of such disposal activities as well as supporting decisions for a future remediation of the zone
Determinación de Sr y Ba en celestinas por fluorescencia de rayos X empleando patrones sintéticos
A rapid and accurate X-ray method for the routine quantitative determination of strontium and barium in celestites is studied. The chemical characteristics of celestites from S.E. of Spain allows the use of synthetic standards with a simple pelleting method. The results obtained by this procedure agree with those found using AAS.Se ha estudiado un método rápido para análisis cuantitativo de estroncio y bario en celestinas por fluorescencia de rayos X. Las características químicas de las celestinas de la zona estudiada de las cordilleras Béticas se han simulado con patrones sintéticos. Los resultados obtenidos han sido contrastados con análisis de muestras naturales efectuadas por espectrometría de absorción atómica
Inorganic arsenic causes apoptosis cell death and immunotoxicity on European sea bass (Dicentrarchus labrax)
Inorganic arsenic (As) is one of the most toxic pollutants in the water. We have studied their effects on the marine teleost European sea bass (Dicentrarchus labrax) at 2 and 10 days of 5 μMofAs2O3 (sub-lethal doses) waterborne exposure. Arsenic accumulates in liver and gill tissues. The expression profile of five genes (bax, blc2, casp3, casp8 and casp9) involved in apoptosis cell death confirmed apoptotic effects in liver, slight changes in gill and no effects in skin according with the histopathology findings. Total IgM level and peroxidase activities were increased at 2 and 10 days, respectively. The bactericidal activity was decreased at 2 days after As exposure. A general decrease of cellular immune activities with significant differences in the case of respiratory burst activity was observed after 2 and 10 days of exposure. This work describes for the first time the effects of As exposure on European sea bass.Versión del editor2,35
Labdane diterpenes protect against anoxia/reperfusion injury in cardiomyocytes: involvement of AKT activation
Several labdane diterpenes exert anti-inflammatory and cytoprotective actions; therefore, we have investigated whether these molecules protect cardiomyocytes in an anoxia/reperfusion (A/R) model, establishing the molecular mechanisms involved in the process. The cardioprotective activity of three diterpenes (T1, T2 and T3) was studied in the H9c2 cell line and in isolated rat cardiomyocyte subjected to A/R injury. In both cases, treatment with diterpenes T1 and T2 protected from A/R-induced apoptosis, as deduced by a decrease in the percentage of apoptotic and caspase-3 active positive cells, a decrease in the Bcl-2/Bax ratio and an increase in the expression of antiapoptotic proteins. Analysis of cell survival signaling pathways showed that diterpenes T1 and T2 added after A/R increased phospho-AKT and phospho-ERK 1/2 levels. These cardioprotective effects were lost when AKT activity was pharmacologically inhibited. Moreover, the labdane-induced cardioprotection involves activation of AMPK, suggesting a role for energy homeostasis in their mechanism of action. Labdane diterpenes (T1 and T2) also exerted cardioprotective effects against A/R-induced injury in isolated cardiomyocytes and the mechanisms involved activation of specific survival signals (PI3K/AKT pathways, ERK1/2 and AMPK) and inhibition of apoptosis
Clinical experience with integrase inhibitors in HIV-2-infected individuals in Spain.
Background: HIV-2 is a neglected virus despite estimates of 1–2 million people being infected worldwide. The virus is naturally resistant to some antiretrovirals used to treat HIV-1 and therapeutic options are limited for patients with HIV-2.
Methods: In this retrospective observational study, we analysed all HIV-2-infected individuals treated with inte- grase strand transfer inhibitors (INSTIs) recorded in the Spanish HIV-2 cohort. Demographics, treatment modal- ities, laboratory values, quantitative HIV-2 RNA and CD4 counts as well as drug resistance were analysed.
Results: From a total of 354 HIV-2-infected patients recruited by the Spanish HIV-2 cohort as of December 2017, INSTIs had been given to 44, in 18 as first-line therapy and in 26 after failing other antiretroviral regimens. After a median follow-up of 13 months of INSTI-based therapy, undetectable viraemia for HIV-2 was achieved in 89% of treatment-naive and in 65.4% of treatment-experienced patients. In parallel, CD4 gains were 82 and 126cells/mm3, respectively. Treatment failure occurred in 15 patients, 2 being treatment-naive and 13 treatment-experienced. INSTI resistance changes were recognized in 12 patients: N155H (5), Q148H/R (3), Y143C/G (3) and R263K (1).
Conclusions: Combinations based on INSTIs are effective and safe treatment options for HIV-2-infected individ- uals. However, resistance mutations to INSTIs are selected frequently in failing patients, reducing the already limited treatment options
Application of bioassays with Enchytraeus crupticus and Folsomia candida to evaluate the toxicity of a metal-contaminated soil, before and after remediation.
Purpose: A contaminated soil was amended to reduce bioavailability of metals (As, Cd, Cu, Pb, and Zn) and to modify its potential environmental impacts. Reproduction toxicity tests using two different soil invertebrates, Enchytraeus crypticus and Folsomia candida, were used to evaluate efficiency of soil amendments to reduce metal availability. Materials and methods: This study has been carried out on a very contaminated soil from El Arteal mining district (SE Spain). The amendments used were marble sludge from the cutting and polishing of marble, compost from greenhouse wastes, and synthetic iron oxides. Soils were analyzed for cation exchange capacity, organic carbon and calcium carbonate content, particle size distribution, pH, electrical conductivity, and total metal content. Porewater and 0.01 M CaC
HTLV-1 infection in solid organ transplant donors and recipients in Spain
HTLV-1 infection is a neglected disease, despite infecting 10-15 million people worldwide and severe illnesses develop in 10% of carriers lifelong. Acknowledging a greater risk for developing HTLV-1 associated illnesses due to immunosuppression, screening is being widely considered in the transplantation setting. Herein, we report the experience with universal HTLV testing of donors and recipients of solid organ transplants in a survey conducted in Spain. All hospitals belonging to the Spanish HTLV network were invited to participate in the study. Briefly, HTLV antibody screening was performed retrospectively in all specimens collected from solid organ donors and recipients attended since the year 2008. A total of 5751 individuals were tested for HTLV antibodies at 8 sites. Donors represented 2312 (42.2%), of whom 17 (0.3%) were living kidney donors. The remaining 3439 (59.8%) were recipients. Spaniards represented nearly 80%. Overall, 9 individuals (0.16%) were initially reactive for HTLV antibodies. Six were donors and 3 were recipients. Using confirmatory tests, HTLV-1 could be confirmed in only two donors, one Spaniard and another from Colombia. Both kidneys of the Spaniard were inadvertently transplanted. Subacute myelopathy developed within 1 year in one recipient. The second recipient seroconverted for HTLV-1 but the kidney had to be removed soon due to rejection. Immunosuppression was stopped and 3 years later the patient remains in dialysis but otherwise asymptomatic. The rate of HTLV-1 is low but not negligible in donors/recipients of solid organ transplants in Spain. Universal HTLV screening should be recommended in all donor and recipients of solid organ transplantation in Spain. Evidence is overwhelming for very high virus transmission and increased risk along with the rapid development of subacute myelopathy
Metallic, magnetic and molecular nanocontacts
Scanning tunnelling microscopy and break-junction experiments realize metallic and molecular nanocontacts that act as ideal one-dimensional channels between macroscopic electrodes. Emergent nanoscale phenomena typical of these systems encompass structural, mechanical, electronic, transport, and magnetic properties. This Review focuses on the theoretical explanation of some of these properties obtained with the help of first-principles methods. By tracing parallel theoretical and experimental developments from the discovery of nanowire formation and conductance quantization in gold nanowires to recent observations of emergent magnetism and Kondo correlations, we exemplify the main concepts and ingredients needed to bring together ab initio calculations and physical observations. It can be anticipated that diode, sensor, spin-valve and spin-filter functionalities relevant for spintronics and molecular electronics applications will benefit from the physical understanding thus obtained
A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)
Meeting abstrac
- …