154 research outputs found
Los blogs y las bibliotecas universitarias españolas: evaluando la blogosfera
Este trabajo analiza el estado de la blogosfera en el ámbito de las bibliotecas universitarias públicas españolas. Una vez adquiridos los conocimientos básicos sobre el origen, funcionamiento y uso de estas herramientas y del entorno 2.0 en el que se desarrollan, se analiza la presencia, el impacto y la actividad que están teniendo los blogs en estas instituciones. Se rastrean las webs de 50 bibliotecas y se seleccionan 30 que gestionan al menos un blog. A partir de una muestra de 183 blogs, se toman como unidad de análisis los 23 que difunden información de carácter general relativa a los recursos, servicios y actividades de la biblioteca. Utilizando una serie de indicadores de producción y participación en los blogs, se evalúa la visibilidad y el grado de actividad que han tenido en el último curso académico. Esto permite obtener una “radiografía” de la situación general e invita a la reflexión sobre el uso que se le está dando a estas herramientas en las bibliotecas universitarias
Competencia informacional
Guía de la Competencia Informacional como competencia transversal de la Universidad de Almería. Se define a la competencia informacional, se marcan sus objetivos y los resultados de su aprendizaj
Superparamagnetic iron oxide nanoparticles decorated mesoporous silica nanosystem for combined antibiofilm therapy
A crucial challenge to face in the treatment of biofilm-associated infection is the ability of bacteria to develop resistance to traditional antimicrobial therapies based on the administration of antibiotics alone. This study aims to apply magnetic hyperthermia together with controlled antibiotic delivery from a unique magnetic-responsive nanocarrier for a combination therapy against biofilm. The design of the nanosystem is based on antibiotic-loaded mesoporous silica nanoparticles (MSNs) externally functionalized with a thermo-responsive polymer capping layer, and decorated in the outermost surface with superparamagnetic iron oxide nanoparticles (SPIONs). The SPIONs are able to generate heat upon application of an alternating magnetic field (AMF), reaching the temperature needed to induce a change in the polymer conformation from linear to globular, therefore triggering pore uncapping and the antibiotic cargo release. The microbiological assays indicated that exposure of E. coli biofilms to 200 µg/mL of the nanosystem and the application of an AMF (202 kHz, 30 mT) decreased the number of viable bacteria by 4 log10 units compared with the control. The results of the present study show that combined hyperthermia and antibiotic treatment is a promising approach for the effective management of biofilm-associated infections.Depto. de Química en Ciencias FarmacéuticasFac. de FarmaciaTRUEpu
Nanoantibiotics Based in Mesoporous Silica Nanoparticles: New Formulations for Bacterial Infection Treatment.
This review focuses on the design of mesoporous silica nanoparticles for infection treat‐ment. Written within a general context of contributions in the field, this manuscript highlights the major scientific achievements accomplished by Prof. Vallet‐Regí’s research group in the field of silica‐based mesoporous materials for drug delivery. The aim is to bring out her pivotal role on the envisage of a new era of nanoantibiotics by using a deep knowledge on mesoporous materials as drug delivery systems and applying cutting‐edge technologies to design and engineer advanced nanoweapons to fight infection. This review has been divided in two main sections: the first part overviews the influence of the textural and chemical properties of silica‐based mesoporous materials on the loading and release of antibiotic molecules, depending on the host‐guest interactions.Furthermore, this section also remarks the potential of molecular modelling in the design and comprehension of the performance of these release systems. The second part describes the more recent advances in the use of mesoporous silica nanoparticles as versatile nanoplatforms for the development of novel targeted and stimuli‐responsive antimicrobial nanoformulations for future application in personalized infection therapies
Characterization and schematic modeling of a family system of bovine milk producers in Ciénega de Chapala, Mexico
Systems theory states that livestock production is dependent on the environment and goals and objectives of the system itself. Therefore, family systems of bovine milk producers (FSBMP) are considered as parallel systems: those in which there is a symbiosis between man and animals and relationships are only affected by environmental factors. The aim of this research was the characterization and schematic modeling of a FSBMP in the region of Ciénega de Chapala, Mexico. For characterization of FSBMP we used general theory of systems methodology and for modeling, a black box approach to integrate criteria such as: (a) internal consistency of the system, (b) interdependence of the system’s components. As a part of characterization, the type of producers was established and milk production was determined by simple random sampling (50% of the herd), milk being weighed at 7-d intervals during 180 d. Data were analyzed using mixed models with repeated measurements methodology. The inefficiency of the FSBMP analyzed (3 416 kg of milk per 305-d of lactation) was attributed to limited formal education of the producer (basic level), which was associated with inefficiencies in administration and in assimilation of technological packages. Milk production presented an abnormal lactation curve and was not affected by the time of year (P > 0.05). In conclusion, efficient functioning of the FSBMP was limited more by knowledge of the producer about the animal component than by the environment in which the system operates
Direct actions of dapagliflozin and interactions with LCZ696 and spironolactone on cardiac fibroblasts of patients with heart failure and reduced ejection fraction
Inhibitors of SGLT2 (SGLT2i) have shown a positive impact in patients with chronic heart failure and reduced ejection fraction (HFrEF). Nonetheless, the direct effects of SGLT2i on cardiac cells and how their association with main drugs used for HFrEF affect the behaviour and signalling pathways of myocardial fibroblasts are still unknown. We aimed to determine the effects of dapagliflozin alone and in combination with sacubitril/valsartan (LCZ696) or spironolactone on the function of myocardial fibroblasts of patients with heart failure and reduced ejection fraction (HFrEF).Myocardial fibroblasts isolated from HFrEF patients (n = 5) were treated with dapagliflozin alone (1 nM-1 ?M) or combined with LCZ696 (100 nM) or spironolactone (100 nM). The migratory rate was determined by wound-healing scratch assay. Expression of heart failure (HF) markers and signalling pathways activation were analysed with multiplexed protein array. Commercially available cardiac fibroblasts from healthy donors were used as Control (n = 4). Fibroblasts from HFrEF show higher migratory rate compared with control (P = 0.0036), and increased expression of HF markers [fold-change (Log2): COL1A1-1.3; IL-1b-1.9; IL-6-1.7; FN1-2.9 (P < 0.05)]. Dapagliflozin slowed the migration rate of HFrEF fibroblasts in a dose-dependent manner and markedly decreased the expression of IL-1?, IL-6, MMP3, MMP9, GAL3, and FN1. SGLT2i had no effect on control fibroblasts. These effects were associated with decreased phosphorylation of AKT/GSK3 and PYK2 kinases and the signal transducer and activator of transcription (STAT). A combination of dapagliflozin + LCZ696 further decreased fibroblast migration, although it did not have a significant effect on the regulation of signalling pathways and the expression of biomarkers induced by SGLT2 inhibition alone. In contrast, the combination of dapagliflozin + spironolactone did not change the migration rate of fibroblast but significantly altered SGLT2i responses on MMP9, GAL3, and IL-1b expression, in association with increased phosphorylation of the kinases AKT/GSK3 and ERK1/2.SGLT2i, LCZ696, and spironolactone modulate the function of isolated myocardial fibroblasts from HFrEF patients through the activation of different signalling pathways. The combination of SGLT2i + LCZ696 shows an additive effect on migration, while spironolactone modifies the signalling pathways activated by SGLT2i and its beneficial effects of biomarkers of heart failure.© 2022 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology
Free Form Deformation-Based Image Registration Improves Accuracy of Traction Force Microscopy
Traction Force Microscopy (TFM) is a widespread method used to recover cellular tractions from the deformation that they cause in their surrounding substrate. Particle Image Velocimetry (PIV) is commonly used to quantify the substrate's deformations, due to its simplicity and efficiency. However, PIV relies on a block-matching scheme that easily underestimates the deformations. This is especially relevant in the case of large, locally non-uniform deformations as those usually found in the vicinity of a cell's adhesions to the substrate. To overcome these limitations, we formulate the calculation of the deformation of the substrate in TFM as a non-rigid image registration process that warps the image of the unstressed material to match the image of the stressed one. In particular, we propose to use a B-spline -based Free Form Deformation (FFD) algorithm that uses a connected deformable mesh to model a wide range of flexible deformations caused by cellular tractions. Our FFD approach is validated in 3D fields using synthetic (simulated) data as well as with experimental data obtained using isolated endothelial cells lying on a deformable, polyacrylamide substrate. Our results show that FFD outperforms PIV providing a deformation field that allows a better recovery of the magnitude and orientation of tractions. Together, these results demonstrate the added value of the FFD algorithm for improving the accuracy of traction recovery.Funded by Ministerio de Economía y Competividad (ES); url: http://www.mineco.gob.es/;
RyC2010-06094, Fundación Ramón Areces (ES); url: http://www.fundacionareces.es/fundacionareces/, Ministerío de Economía y Competividad (ES); url: http://www.mineco.gob.es/; SAF2011-24953 (MVM); Ministerio de Economía y Competividad (ES); url: http://www.mineco.gob.es/; DPI2012-38090-C1, European Research Council (BE); url: http://erc.europa.eu/; 306751 (JMGA); European Research Council (BE); url: http://erc.europa.eu/; 308223 (HVO); Ministerio de Economía y Competividad (ES);
url: http://www.mineco.gob.es/; DPI2012-38090-C3 (COS); and Ministerio de Economía y Competividad (ES); url: http://www.mineco.gob.es/; TEC2013- 48552-C2-1-R (AMB). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.European Community's Seventh Framework Progra
Telomeric Repeat-Binding Factor Homologs in Entamoeba histolytica: New Clues for Telomeric Research
Telomeric Repeat Binding Factors (TRFs) are architectural nuclear proteins with critical roles in telomere-length regulation, chromosome end protection and, fusion prevention, DNA damage detection, and senescence regulation. Entamoeba histolytica, the parasite responsible of human amoebiasis, harbors three homologs of human TRFs, based on sequence similarities to their Myb DNA binding domain. These proteins were dubbed EhTRF-like I, II and III. In this work, we revealed that EhTRF-like I and II share similarity with human TRF1, while EhTRF-like III shares similarity with human TRF2 by in silico approach. The analysis of ehtrf-like genes showed they are expressed differentially under basal culture conditions. We also studied the cellular localization of EhTRF-like I and III proteins using subcellular fractionation and western blot assays. EhTRF-like I and III proteins were enriched in the nuclear fraction, but they were also present in the cytoplasm. Indirect immunofluorescence showed that these proteins were located at the nuclear periphery co-localizing with Lamin B1 and trimethylated H4K20, which is a characteristic mark of heterochromatic regions and telomeres. We found by transmission electron microscopy that EhTRF-like III was located in regions of more condensed chromatin. Finally, EMSA assays showed that EhTRF-like III forms specific DNA-protein complexes with telomeric related sequences. Our data suggested that EhTRF-like proteins play a role in the maintenance of the chromosome ends in this parasite
The MADS transcription factor XAL2/AGL14 modulates auxin transport during Arabidopsis root development by regulating PIN expression
Elucidating molecular links between cell-fate regulatory networks and dynamic patterning modules is a key for understanding development. Auxin is important for plant patterning, particularly in roots, where it establishes positional information for cell-fate decisions. PIN genes encode plasma membrane proteins that serve as auxin efflux transporters; mutations in members of this gene family exhibit smaller roots with altered root meristems and stem-cell patterning. Direct regulators of PIN transcription have remained elusive. Here, we establish that a MADS-box gene (XAANTAL2, XAL2/AGL14) controls auxin transport via PIN transcriptional regulation during Arabidopsis root development; mutations in this gene exhibit altered stem-cell patterning, root meristem size, and root growth. XAL2 is necessary for normal shootward and rootward auxin transport, as well as for maintaining normal auxin distribution within the root. Furthermore, this MADS-domain transcription factor upregulates PIN1 and PIN4 by direct binding to regulatory regions and it is required for PIN4-dependent auxin response. In turn, XAL2 expression is regulated by auxin levels thus establishing a positive feedback loop between auxin levels and PIN regulation that is likely to be important for robust root patterning.This work was supported by grants from CONACYT, México: Red Tematica de Investigacion: ‘Complejidad, Ciencia y Sociedad’ (124909; ERAB; BGP; AGA) and 81542 and 105678 (ERAB), 167705 (AGA), 152649 (MPS), 81433 (BGP), 177739 (SF) and 127957 (JGD), from PAPIIT-UNAM, IN204011-3 (BGP), IN229009-3 (ERAB), IN226510-3 (AGA), IB201212 (MPS), and IN204312 (JGD), from the Spanish Government BFU2012-33746 (SP) and from the National Science Foundation (NSF-IOS) 0820648 (ASM). ERAB acknowledges the support of the Miller Institute for Basic Research in Science, University of California, Berkeley while spending a sabbatical leave in the laboratory of Chelsea Specht at UC-B.Peer reviewe
- …