187 research outputs found

    10 kg scaled-up preparation of Al/Fe-pillared clay CWPO catalysts from concentrated precursors

    Get PDF
    In this work, the significant intensification of a bentonite pillaring process was achieved by using a novel methodological approach, leading to an intercalating Al/Fe mixed oligomeric precursor, around 100 times more concentrated than usually reported. In addition, the intercalating step was achieved directly on the clay with no previous swelling of the mineral being required; this allowed the successful scaled-up preparation of the Al/Fe-PILC, by a factor of one thousand, from the lab (10 g) to the pilot scale (10 kg). Intercalating solutions prepared under either oncentrated (13 cm3) or diluted (widely reported, 2.0 dm3) conditions for lab-scale preparations were both translucent, displaying similar final pH values (close to 4.0) typical of highly oligomerized Al-pillaring solutions. The clay modified from concentrated precursors at the 10 g scale reached a high basal spacing (18.3 Å) and specific surface area (198 m2 g−1 ) with very comparable fractions of Fe forming truly mixed Al/Fe pillars in comparison to a reference material (H2-TPR analyses). This promoted high performance in the catalytic wet peroxide oxidation of phenol in aqueous solution as a toxic model organic molecule at very mild temperature (25.0 °C ± 1.0 °C) and pressure (76 kPa), exhibiting the highest catalytic efficiency as a function of both parameters (full conversion of phenol together with 45.2% of TOC mineralization) with low iron leaching using a very low catalyst concentration (0.25 g dm−3). Particle size refining of the starting clay, the speed of stirring and conditions for the final washing of the interlayered precursor are the main factors influencing successful pillaring at scales higher than 1.0 kg

    Trophic consequences of introduced species: comparative impacts of increased inter-specific versus intra-specific competitive interactions

    Get PDF
    1. Invasive species can cause substantial ecological impacts on native biodiversity. Whilst ecological theory attempts to explain the processes involved in the trophic integration of invaders into native food webs and their competitive impacts on resident species, results are equivocal. In addition, quantifying the relative strength of impacts from non-native species (inter-specific competition) versus the release of native conspecifics (intra-specific competition) is important but rarely completed. 2. Two model non-native fishes, the globally invasive Cyprinus carpio and Carassius auratus, and the model native fish Tinca tinca, were used in a pond experiment to test how increased intra- and inter-specific competition influenced trophic niches and somatic growth rates. This was complemented by samples collected from three natural fish communities where the model fishes were present. The isotopic niche, calculated using stable isotope data, represented the trophic niche. 3. The pond experiment used additive and substitutive treatments to quantify the trophic niche variation that resulted from intra- and inter-specific competitive interactions. Although the trophic niche sizes of the model species were not significantly altered by any competitive treatment, they all resulted in patterns of inter-specific niche divergence. Increased inter-specific competition caused the trophic niche of T. tinca to shift to a significantly higher trophic position, whereas intra-specific competition caused its position to shift towards elevated 13C. These patterns were independent of impacts on fish growth rates, which were only significantly altered when inter-specific competition was elevated. 4. In the natural fish communities, patterns of trophic niche partitioning between the model fishes was evident, with no niche sharing. Comparison of these results with those of the experiment revealed the most similar results between the two approaches were for the niche partitioning between sympatric T. tinca and C. carpio. 5. These results indicate that trophic niche divergence facilitates the integration of introduced species into food webs, but there are differences in how this manifests between introductions that increase inter- and intra-specific competition. In entirety, these results suggest that the initial ecological response to an introduction appears to be a trophic re-organisation of the food web that minimises the trophic interactions between competing species

    Automatic quantification of cardiomyocyte dimensions and connexin 43 lateralization in fluorescence images

    Get PDF
    Cardiomyocytes’ geometry and connexin 43 (CX43) amount and distribution are structural features that play a pivotal role in electrical conduction. Their quantitative assessment is of high interest in the study of arrhythmias, but it is usually hampered by the lack of automatic tools. In this work, we propose a software algorithm (Myocyte Automatic Retrieval and Tissue Analyzer, MARTA) to automatically detect myocytes from fluorescent microscopy images of cardiac tissue, measure their morphological features and evaluate the expression of CX43 and its degree of lateralization. The proposed software is based on the generation of cell masks, contouring of individual cells, enclosing of cells in minimum area rectangles and splitting of these rectangles into end-to-end and middle compartments to estimate CX43 lateral-to-total ratio. Application to human ventricular tissue images shows that mean differences between automatic and manual methods in terms of cardiomyocyte length and width are below 4 ”m. The percentage of lateral CX43 also agrees between automatic and manual evaluation, with the interquartile range approximately covering from 3% to 30% in both cases. MARTA is not limited by fiber orientation and has an optimized speed by using contour filtering, which makes it run hundreds of times faster than a trained expert. Developed for CX43 studies in the left ventricle, MARTA is a flexible tool applicable to morphometric and lateralization studies of other markers in any heart chamber or even skeletal muscle. This open-access software is available online

    Comprehensive plasma proteomic profiling reveals biomarkers for active tuberculosis

    Get PDF
    BACKGROUND. Tuberculosis (TB) kills more people than any other infection, and new diagnostic tests to identify active cases are required. We aimed to discover and verify novel markers for TB in nondepleted plasma. / METHODS. We applied an optimized quantitative proteomics discovery methodology based on multidimensional and orthogonal liquid chromatographic separation combined with high-resolution mass spectrometry to study nondepleted plasma of 11 patients with active TB compared with 10 healthy controls. Prioritized candidates were verified in independent UK (n = 118) and South African cohorts (n = 203). / RESULTS. We generated the most comprehensive TB plasma proteome to date, profiling 5022 proteins spanning 11 orders-of-magnitude concentration range with diverse biochemical and molecular properties. We analyzed the predominantly low–molecular weight subproteome, identifying 46 proteins with significantly increased and 90 with decreased abundance (peptide FDR ≀ 1%, q ≀ 0.05). Verification was performed for novel candidate biomarkers (CFHR5, ILF2) in 2 independent cohorts. Receiver operating characteristics analyses using a 5-protein panel (CFHR5, LRG1, CRP, LBP, and SAA1) exhibited discriminatory power in distinguishing TB from other respiratory diseases (AUC = 0.81). / CONCLUSION. We report the most comprehensive TB plasma proteome to date, identifying novel markers with verification in 2 independent cohorts, leading to a 5-protein biosignature with potential to improve TB diagnosis. With further development, these biomarkers have potential as a diagnostic triage test. / FUNDING. Colciencias, Medical Research Council, Innovate UK, NIHR, Academy of Medical Sciences, Program for Advanced Research Capacities for AIDS, Wellcome Centre for Infectious Diseases Research

    Non-destructive Techniques Methodologies for the Detection of Ancient Structures under Heritage Buildings

    Full text link
    [EN] Structures and elements buried beneath heritage buildings are frequent but are often unknown and inaccessible. Therefore, they are difficult to locate in general if an archaeological excavation is not carried out, with the economic cost and time involved. It is important to discover them in order to increase our knowledge of cultural heritage, as well as to know, recover and improve the state of conservation of the materials that make up these structures. This paper presents methodologies for locating old structures using a low-cost NDT approach, with a qualitative and quantitative analysis of GPR profiles in heritage buildings. Small perforations are performed at critical points and introducing an endoscope for verification. Various crypts have been located using the proposed methodologies in a real study case: The Church of the AsuciĂłn of LlĂ­ria in Spain.Gil Benso, E.; Mas Tomas, MDLA.; Lerma Elvira, C.; Torner, ME.; Vercher Sanchis, J. (2021). Non-destructive Techniques Methodologies for the Detection of Ancient Structures under Heritage Buildings. International journal of architectural heritage (electronic). 15(10):1457-1473. https://doi.org/10.1080/15583058.2019.1700320S14571473151

    Analysis of age-related left ventricular collagen remodeling in living donors: Implications in arrhythmogenesis

    Get PDF
    Age-related fibrosis in the left ventricle (LV) has been mainly studied in animals by assessing collagen content. Using second-harmonic generation microscopy and image processing, we evaluated amount, aggregation and spatial distribution of LV collagen in young to old pigs, and middle-age and elder living donors. All collagen features increased when comparing adult and old pigs with young ones, but not when comparing adult with old pigs or middle-age with elder individuals. Remarkably, all collagen parameters strongly correlated with lipofuscin, a biological age marker, in humans. By building patient-specific models of human ventricular tissue electrophysiology, we confirmed that amount and organization of fibrosis modulated arrhythmia vulnerability, and that distribution should be accounted for arrhythmia risk assessment. In conclusion, we characterize the age-associated changes in LV collagen and its potential implications for ventricular arrhythmia development. Consistency between pig and human results substantiate the pig as a relevant model of age-related LV collagen dynamics. © 2022 The Author(s

    Biocompatible nanocomposite for PET/MRI hybrid imaging

    Get PDF
    A novel nanocarrier system was designed and developed with key components uniquely structured at the nanoscale for early cancer diagnosis and treatment. In order to perform magnetic resonance imaging, hydrophilic superparamagnetic maghemite nanoparticles (NPs) were synthesized and coated with a lipophilic organic ligand. Next, they were entrapped into polymeric NPs made of biodegradable poly(lactic-co-glycolic acid) linked to polyethylene glycol. In addition, resulting NPs have been conjugated on their surface with a 2,2'-(7-(4-((2-aminoethyl)amino)-1-carboxy-4-oxobutyl)-1,4,7-triazonane-1,4-diyl)diacetic acid ligand for subsequent 68Ga incorporation. A cell-based cytotoxicity assay has been employed to verify the in vitro cell viability of human pancreatic cancer cells exposed to this nanosystem. Finally, in vivo positron emission tomography-computerized tomography biodistribution studies in healthy animals were performed

    Impact of the COVID-19 pandemic on the organisation of stroke care. Madrid Stroke Care Plan

    Full text link
    La sobrecarga asistencial y los cambios organizativos frente a la pandemia de COVID-19 podrĂ­an estar repercutiendo en la atenciĂłn al ictus agudo en la Comunidad de Madrid. MĂ©todos: Encuesta estructurada en bloques: caracterĂ­sticas del hospital, cambios en infraestructura y recursos, circuitos de cĂłdigo ictus, pruebas diagnĂłsticas, rehabilitaciĂłn y atenciĂłn ambulatoria. AnĂĄlisis descriptivo segĂșn el nivel de complejidad en la atenciĂłn del ictus (disponibilidad o no de unidad de ictus y de trombectomĂ­a mecĂĄnica). Resultados: De los 26 hospitales del SERMAS que atienden urgencias en adultos, 22 cumplimentaron la encuesta entre el 16 y 27 de abril. El 95% han cedido neurĂłlogos para atender a pacientes afectados por la COVID-19. Se han reducido camas de neurologĂ­a en el 89,4%, modificado los circuitos en urgencias para ictus en el 81%, con circuitos especĂ­ficos para sospecha de infecciĂłn por SARS-CoV2 en el 50%, y en el 42% de los hospitales los pacientes con ictus agudo positivos para SARS-CoV2 no ingresan en camas de neurologĂ­a. Ha mejorado el acceso altratamiento, con trombectomĂ­a mecĂĄnica las 24 h en el propio hospital en 10 hospitales, y sehan reducido los traslados interhospitalarios secundarios. Se ha evitado el ingreso de pacientescon ataque isquĂ©mico transitorio o ictus leve (45%) y se han incorporado consultas telefĂłnicaspara seguimiento en el 100%.Conclusiones: Los cambios organizativos de los hospitales de la Comunidad de Madrid frente ala pandemia por SARS-Co2 han modificado la dedicaciĂłn de recursos humanos e infraestructurasde las unidades de neurologĂ­a y los circuitos de atenciĂłn del ictus, realizaciĂłn de pruebasdiagnĂłsticas, ingreso de los pacientes y seguimientoThe overload of the healthcare system and the organisational changes made inresponse to the COVID-19 pandemic may be having an impact on acute stroke care in the Regionof Madrid.Methods: We conducted a survey with sections addressing hospital characteristics, changes ininfrastructure and resources, code stroke clinical pathways, diagnostic testing, rehabilitation,and outpatient care. We performed a descriptive analysis of results according to the level ofcomplexity of stroke care (availability of stroke units and mechanical thrombectomy).Results: The survey was completed by 22 of the 26 hospitals in the Madrid Regional HealthSystem that attend adult emergencies, between 16 and 27 April 2020. Ninety-five percent ofhospitals had reallocated neurologists to care for patients with COVID-19. The numbers of neuro-logy ward beds were reduced in 89.4% of hospitals; emergency department stroke care pathwayswere modified in 81%, with specific pathways for suspected SARS-CoV2 infection established in50% of hospitals; and SARS-CoV2-positive patients with acute stroke were not admitted to neu-rology wards in 42%. Twenty-four hour on-site availability of mechanical thrombectomy wasimproved in 10 hospitals, which resulted in a reduction in the number of secondary hospitaltransfers. The admission of patients with transient ischaemic attack or minor stroke was avoi-ded in 45% of hospitals, and follow-up through telephone consultations was implemented in100%.Conclusions: The organisational changes made in response to the SARS-Co2 pandemic in hos-pitals in the Region of Madrid have modified the allocation of neurology department staff andinfrastructure, stroke units and stroke care pathways, diagnostic testing, hospital admissions,and outpatient follow-u

    Liver injury in non-alcoholic fatty liver disease is associated with urea cycle enzyme dysregulation

    Get PDF
    The main aim was to evaluate changes in urea cycle enzymes in NAFLD patients and in two preclinical animal models mimicking this entity. Seventeen liver specimens from NAFLD patients were included for immunohistochemistry and gene expression analyses. Three-hundred-and-eighty-two biopsy-proven NAFLD patients were genotyped for rs1047891, a functional variant located in carbamoyl phosphate synthetase-1 (CPS1) gene. Two preclinical models were employed to analyse CPS1 by immunohistochemistry, a choline deficient high-fat diet model (CDA-HFD) and a high fat diet LDLr knockout model (LDLr −/−). A significant downregulation in mRNA was observed in CPS1 and ornithine transcarbamylase (OTC1) in simple steatosis and NASH-fibrosis patients versus controls. Further, age, obesity (BMI > 30 kg/m), diabetes mellitus and ALT werefound to be risk factors whereas A-allele from CPS1 was a protective factor from liver fibrosis. CPS1 hepatic expression was diminished in parallel with the increase of fibrosis, and its levels reverted up to normality after changing diet in CDA-HFD mice. In conclusion, liver fibrosis and steatosis were associated with a reduction in both gene and protein expression patterns of mitochondrial urea cycle enzymes. A-allele from a variant on CPS1 may protect from fibrosis development. CPS1 expression is restored in a preclinical model when the main trigger of the liver damage disappears.The research leading to these results has received funding from the ConsejerĂ­a de Salud de la Junta de AndalucĂ­a under grant agreement PC-0148-2016-0148 and PE-0451-2018 and Instituto de Salud Carlos III under grant agreements CD21/00095, PI16/01842, PI19/01404, PI19/00589, IFI18/00041, FI20/00201, CD18/00126 and EHD18PI04/2021. RocĂ­o Gallego-DurĂĄn has received the Andrew K Burroughs Fellowship from European Association for the Study of the Liver (EASL), Aprendizaje de Nuevas TecnologĂ­as fellowship from AsociaciĂłn Española para el Estudio del HĂ­gado (AEEH) and CIBERehd Grant to support researcher’s mobility
    • 

    corecore