940 research outputs found
La responsabilidad de las plataformas online en los contratos con consumidores, según la Propuesta de Reglamento de Servicios Digitales
[eng] This paper analyses the European legislation and case law regarding the liability of online platforms and critically assesses the Proposal for a Digital Services Act released by the European Commission in December 2020.[spa] El trabajo analiza la legislación y jurisprudencia europea sobre la responsabilidad de las plataformas online y enjuicia críticamente la Propuesta de Digital Services Act que la Comisión europea hizo pública el pasado mes de diciembre de 2020.[cat] El treball analitza la legislació i jurisprudència europea sobre la responsabilitat de les plataformes en línia i valora críticament la Proposta de Digital Services Act que la Comissió Europea va fer pública el passat mes de desembre de 202
Hacia una pedagogía de los valores en la Educación Superior
Se analiza el Proyecto Educativo como vía para desarrollar la educación en valores del estudiante de la Educación Superior en Cuba, lo cual puede generalizarse a otros contextos educativos.
Se ofrecen las premisas y requerimientos para la concepción de un Proyecto Educativo científicamente fundamentado en las leyes y regularidades del proceso pedagógico En las bases psicopedagógicas para el diagnóstico se trata de precisar el lugar que ocupan los valores en la estructura de la personalidad y su relación con otras categorías psicológicas.
Se concluye proponiendo que se tomen como base las esferas de actuación del estudiante universitario: las dimensiones curricular, sociopolítica y extensionista. El conteni-do esencial de las mismas se ha integrado en categorías que se podrán explorar mediante indicadores
Cloning, characterization and analysis of cat and ben genes from the phenol degrading halophilic bacterium Halomonas organivorans.
Background: Extensive use of phenolic compounds in industry has resulted in the generation of saline wastewaters that
produce significant environmental contamination; however, little information is available on the degradation of phenolic
compounds in saline conditions. Halomonas organivorans G-16.1 (CECT 5995T) is a moderately halophilic bacterium that we
isolated in a previous work from saline environments of South Spain by enrichment for growth in different pollutants,
including phenolic compounds. PCR amplification with degenerate primers revealed the presence of genes encoding ringcleaving
enzymes of the b-ketoadipate pathway for aromatic catabolism in H. organivorans.
Findings: The gene cluster catRBCA, involved in catechol degradation, was isolated from H. organivorans. The genes catA,
catB, catC and the divergently transcribed catR code for catechol 1,2-dioxygenase (1,2-CTD), cis,cis-muconate
cycloisomerase, muconolactone delta-isomerase and a LysR-type transcriptional regulator, respectively. The benzoate
catabolic genes (benA and benB) are located flanking the cat genes. The expression of cat and ben genes by phenol and
benzoic acid was shown by RT-PCR analysis. The induction of catA gene by phenol and benzoic acid was also probed by the
measurement of 1,2-CTD activity in H. organivorans growth in presence of these inducers. 16S rRNA and catA gene-based
phylogenies were established among different degrading bacteria showing no phylogenetic correlation between both
genes.
Conclusions/Significance: In this work, we isolated and determined the sequence of a gene cluster from a moderately
halophilic bacterium encoding ortho-pathway genes involved in the catabolic metabolism of phenol and analyzed the gene
organization, constituting the first report characterizing catabolic genes involved in the degradation of phenol in moderate
halophiles, providing an ideal model system to investigate the potential use of this group of extremophiles in the
decontamination of saline environments
Efectividad y seguridad de erenumab y fremanezumab en la prevención de la migraña crónica y la migraña episódica de alta frecuencia: estudio observacional descriptivo en la práctica clínica real
Introducción: la migraña tiene una alta prevalencia en nuestra población. Su tratamiento preventivo es complejo debido a que, hasta hace aproximadamente 18 meses, no disponíamos de ningún fármaco específicamente diseñado para ello. Erenumab y fremanezumab son anticuerpos que actúan sobre el receptor del CGRP (péptido relacionado con el gen de la calcitonina) o sobre el ligando respectivamente que han demostrado ser eficaces en la prevención de la migraña episódica de alta frecuencia (MEAF) y en la migraña crónica (MC). Este neuropéptido está implicado en la fisiopatología de la migraña y está elevado en un elevado porcentaje de pacientes con migraña frente a controles sanos. Método: Estudio observacional prospectivo unicéntrico en el que se incluyeron de forma consecutiva a pacientes con MC y MEAF que iniciaron tratamiento con erenumab 70mg o 140mg y fremanezumab 225mg mensual. Se recogieron variables demográficas, clínicas, de respuesta y tolerabilidad en situación basal, a los tres y 6 meses. Resultados: Se incluyeron 36 y 30 pacientes que iniciaron tratamiento con erenumab y fremanezumab respectivamente. Ambos anticuerpos han conseguido una disminución estadísticamente significativa en el número de días de migraña al mes (DMM). Tras 6 meses de tratamiento con erenumab se consiguió una disminución de 12 DMM y el 72,2% de los pacientes presentó una disminución ≥50% en los DMM. Con fremanezumab se obtuvo una disminución de 9 DMM y el 81,8% de los pacientes presentó una disminución en los DMM ≥50%. Además, en ambos hubo mejoría significativa en la intensidad del dolor, consumo de analgésicos, y puntuación en escalas de calidad de vida y comorbilidad. Conclusiones: Erenumab y fremanezumab son efectivos en el tratamiento preventivo de pacientes con MC y MEAF. Los pacientes del estudio obtuvieron una reducción significativa en el número de DMM y mejoraron aspectos de su calidad de vida. Los efectos secundarios fueron escasos y leves, por lo que a corto plazo ambos fármacos son bien tolerados y seguros. PALABRAS CLAVE: migraña crónica, migraña episódica de alta frecuencia, anticuerpos monoclonales, erenumab, fremanezumab<br /
pH influences the interfacial properties of blue whiting (M. poutassou) and whey protein hydrolysates determining the physical stability of fish oil-in-water emulsions
This work was funded by the project CTQ2017-87076-R from the Spanish Ministry of Science and Innovation. Julia Maldonado-Valderrama and Teresa del Castillo-Santaella acknowledge financialsupport from project RTI2018-101309-B-C21. The authors are also very grateful to F. Javier Espejo-Carpio and Marta Padial-Dominguez for providing the whey and blue whiting protein hydrolysates. Funding for open access charge: Universidad de Granada/CBUA.This work investigates the influence of the interfacial properties of whey protein (WPH) and blue whiting protein (BPH) hydrolysates on the physical stability of fish oil-in-water emulsions stabilized with these hydrolysates at pH 2 or 8. Measurements of interfacial tension and dilatational rheology confirmed that pH is a key factor affecting these interfacial properties of WPH and BPH. WPH, when tested at 1 and 10 mg/mL, showed a higher interfacial activity at pH 8 when compared to pH 2 or to BPH at pH 8 or 2, despite having a lower protein content. Moreover, when tested at 0.1 and 1 mg/mL, the dilatational modulus of WPH was significantly higher at pH 8 than at pH 2. These findings correlate with the formation of smaller oil droplets and a more resistant interfacial peptide layer for WPH at pH 8, hence explaining the improved physical stability of the 5% fish oil-in water emulsion stabilized with WPH at pH 8. BPH did not show significant differences in interfacial activity with pH but exhibited significantly higher dilatational elasticity and viscosity at pH 2 compared to pH 8 (when measured at 0.1 mg/mL and 0.01 or 0.1 Hz). This correlates with the formation of stable 5% fish oil-in-water emulsions with BPH at pH 2 but not at pH 8.Spanish Government CTQ2017-87076-
Mitochondrial free [Ca2+] levels and the permeability transition
Producción CientíficaMitochondrial Ca2+ activates many processes, from mitochondrial metabolism to opening of the permeability
transition pore (PTP) and apoptosis. However, there is considerable controversy regarding the
free mitochondrial [Ca2+] ([Ca2+]M) levels that can be attained during cell activation or even in mitochondrial
preparations. Studies using fluorescent dyes (rhod-2 or similar), have reported that phosphate
precipitation precludes [Ca2+]M from increasing above 2–3 M. Instead, using low-Ca2+-affinity aequorin
probes, we have measured [Ca2+]M values more than two orders of magnitude higher. We confirm here
these values by making a direct in situ calibration of mitochondrial aequorin, and we show that a prolonged
increase in [Ca2+]M to levels of 0.5–1mM was actually observed at any phosphate concentration
(0–10mM) during continuous perfusion of 3.5–100 MCa2+-buffers. In spite of this high and maintained
(>10 min) [Ca2+]M, mitochondria retained functionality and the [Ca2+]M drop induced by a protonophore
was fully reversible. In addition, this high [Ca2+]M did not induce PTP opening unless additional activators
(phenyl arsine oxide, PAO) were present. PAO induced a rapid, concentration-dependent and irreversible
drop in [Ca2+]M. In conclusion [Ca2+]M levels of 0.5–1mM can be reached and maintained for prolonged
periods (>10 min) in phosphate-containing medium, and massive opening of PTP requires additional pore
activators
Discovery of a Potent α ‑ Galactosidase Inhibitor by in Situ Analysis of a Library of Pyrrolizidine − (Thio)urea Hybrid Molecules Generated via Click Chemistry
The parallel synthesis of a 26-membered-library of
aromatic/aliphatic-(thio)urea-linked pyrrolizidines followed by in situ
biological evaluation toward
α
-galactosidases has been carried out.
The combination of the (thio)urea-forming click reaction and the in
situ screening is pioneer in the search for glycosidase inhibitors and
has allowed the discovery of a potent co
ff
ee bean
α
-galactosidase
inhibitor (IC
50
= 0.37
μ
M,
K
i
= 0.12
μ
M) that has also showed
inhibition against human lysosomal
α
-galactosidase (
α
-Gal A, IC
50
=
5.3
μ
M,
K
i
= 4.2
μ
M).Ministerio de Economía y Competitividad (CTQ2016-77270-R)Junta de Andalucía (FQM-345
Ca2+ Dynamics in the Secretory Vesicles of Neurosecretory PC12 and INS1 Cells
Producción CientíficaWe have investigated the dynamics of the free
[Ca2+] inside the secretory granules of neurosecretory PC12
and INS1 cells using a low-Ca2+-affinity aequorin chimera
fused to synaptobrevin-2. The steady-state secretory granule
[Ca2+] ([Ca2+]SG] was around 20–40 lM in both cell types,
about half the values previously found in chromaffin cells.
Inhibition of SERCA-type Ca2+ pumps with thapsigargin
largely blocked Ca2+ uptake by the granules in
Ca2+-depleted permeabilized cells, and the same effect was
obtained when the perfusion medium lacked ATP. Consistently,
the SERCA-type Ca2+ pump inhibitor benzohydroquinone
induced a rapid release of Ca2+ from the granules
both in intact and permeabilized cells, suggesting that the
continuous activity of SERCA-type Ca2+ pumps is essential
to maintain the steady-state [Ca2+]SG. Both inositol 1,4,
5-trisphosphate (InsP3) and caffeine produced a rapid Ca2+
release from the granules, suggesting the presence of InsP3
and ryanodine receptors in the granules. The response to
high-K+ depolarization was different in both cell types, a
decrease in [Ca2+]SG in PC12 cells and an increase in
[Ca2+]SG in INS1 cells. The difference may rely on the
heterogeneous response of different vesicle populations in
each cell type. Finally, increasing the glucose concentration
triggered a decrease in [Ca2+]SG in INS1 cells. In conclusion,
our data show that the secretory granules of PC12 and INS1
cells take up Ca2+ through SERCA-type Ca2+ pumps and
can release it through InsP3 and ryanodine receptors, supporting
the hypothesis that secretory granule Ca2+ may be
released during cell stimulation and contribute to secretion
A confocal study on the visualization of chromaffin cell secretory vesicles with fluorescent targeted probes and acidic dyes
Producción CientíficaSecretory vesicles have low pH and have been classically identified as those labelled by a series of acidic
fluorescent dyes such as acridine orange or neutral red, which accumulate into the vesicles according to
the pH gradient. More recently, several fusion proteins containing enhanced green fluorescent protein
(EGFP) and targeted to the secretory vesicles have been engineered. Both targeted fluorescent proteins
and acidic dyes have been used, separately or combined, to monitor the dynamics of secretory vesicle
movements and their fusion with the plasma membrane. We have now investigated in detail the degree
of colocalization of both types of probes using several fusion proteins targeted to the vesicles (synaptobrevin2-
EGFP, Cromogranin A-EGFP and neuropeptide Y-EGFP) and several acidic dyes (acridine orange,
neutral red and lysotracker red) in chromaffin cells, PC12 cells and GH3 cells. We find that all the acidic
dyes labelled the same population of vesicles. However, that population was largely different from the
one labelled by the targeted proteins, with very little colocalization among them, in all the cell types
studied. Our data show that the vesicles containing the proteins more characteristic of the secretory vesicles
are not labelled by the acidic dyes, and vice versa. Peptide glycyl-L-phenylalanine 2-naphthylamide
(GPN) produced a rapid and selective disruption of the vesicles labelled by acidic dyes, suggesting that
they could be mainly lysosomes. Therefore, these labelling techniques distinguish two clearly different
sets of acidic vesicles in neuroendocrine cells. This finding should be taken into account whenever vesicle
dynamics is studied using these techniques
- …