571 research outputs found
Factores pronósticos en el implante de prótesis valvular aórtica a través de catéter
La hipótesis de esta Tesis Doctoral es que existen factores clínicos y de imagen en los pacientes con estenosis aórtica severa sometidos a implante de prótesis percutánea aórtica (TAVI) que permiten determinar qué pacientes presentarán una mala evolución. En concreto:
¿ La insuficiencia mitral moderada-severa está presente en la mitad de los pacientes sometidos a TAVI. La calcificación de los velos y una dilatación del anillo mitral por tomografía computerizada identifica la persistencia de insuficiencia mitral.
¿ La fibrilación auricular de novo tras el implante de TAVI es frecuente, en particular, cuando hay mayor tamaño auricular izquierdo y abordaje transapical. Además, su presencia se asocia con mayor incidencia de ictus lo cual tiene importantes implicaciones pronósticas y terapeuticas.
¿ El abordaje transapical para el implante de prótesis aórticas percutáneas presenta con frecuencia complicaciones. El empleo de analgesia torácica epidural se asocia a una significativa reducción de éstas y de la mortalidad.Departamento de Medicina, Dermatología y Toxicologí
Legal Protection Plant Biological Matter, Transgenic Products, Patents, and Plant Byproducts
La relevancia del tema abordado se basa en el conocimiento del régimen jurídico sobre la protección de la materia biológica vegetal y las variedades vegetales, dada su relevancia e implementación práctica en el campo de la innovación agroalimentaria y del comercio internacional. En primer lugar, se aporta claridad científica a los conceptos y definiciones legales acerca de las variedades y obtenciones vegetales y los organismos transgénicos. Seguidamente, partiendo del Derecho internacional convencional (Tratados), se examinan diversos modelos jurídicos para la protección legal de nuevas variedades y de material vegetal (Unión Europea/España, con especial énfasis en Brasil). Se estudian también las sincronías y desajustes entre los dos posibles sistemas jurídicos de protección: título de obtención vegetal y patente de invención. Finalmente se analiza el desarrollo a nivel mundial de las solicitudes y títulos sobre obtenciones vegetales.The relevance of the topic addressed is based on the knowledge of the legal system on the protection of plant biological mater and plant varieties, given its importance and practical implementation in the field of agricultural and food innovation and international trade. First, the article provides scientific explanation to legal concepts and definitions about plant varieties and byproducts and transgenic organisms. Second, and based on the conventional international law (treaties), several legal systems on the legal protection of new varieties and plant material (European Union/Spain, with special emphasis on Brazil) are analyzed. Synchronies and malfunction between the two potential legal systems on protection (plant byproducts title and invention patent) are also studied. Finally, the world development of requests and titles on plant byproducts is analyzed
Combining tissue engineering with metal scaffolds in orthopaedic to improve osseointegration of endoprothesis
Electron Beam Melting (EBM) technology allows the fabrication of free-formed metal scaffolds, thus creating the possibility of manufacturing patient-specific endo-prostheses. It also allows the production of highly-porous prostheses with an elastic modulus similar to that of bone. The porous can be filled-in with tissue engineering elements (i.e. osteogenic molecules, biomaterials, cells) in order to promote bone ingrowth inside them, thus improving the prostheses osseointegration. For this purpose, the surface of EBM-sintered titanium should permit cell adhesion, growth and differentiation to ensure a good metal-to-tissue interaction. Our goal was to evaluate the osteoconductivity of EBM-manufactured Ti6Al4V porous scaffolds.
Porous Ti6Al4V discs were manufactured by EBM-sintering, autoclave-sterilized and seeded with human and rat osteoblasts and mesenchymal stem cells (MSC). Cell adhesion, proliferation and differentiation were assessed by vital staining, MTT assay, RT-PCR and immunostaining techniques. Bone organ-explant culture was used to further assess osteoconductivity at tissue level in vitro.
Both osteoblastic and MSC attached to and grew on the titanium discs, covering up the entire metal surface, and even bridging the pores of the scaffold. Collagen type I, osteopontin, and osteocalcin expression confirmed the osseous differentiation of the cells cultured on the titanium discs. Bone explants placed on EBM-sintered titanium alloy spontaneously released cells that covered up the metal surface. Long-term cultured explants strongly adhered to the titanium.
EBM-sintered titanium scaffolds promote cell adhesion and can be populated by osteoblastic and MSC, which can normally differentiate towards the osteogenic lineage upon proper stimulation. These osteoconductive properties should promote the osseointegration of EBM-manufactured endoprostheses for bone replacement.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
New Challenging Scenarios in Transcatheter Aortic Valve Implantation: Valve-in-valve, Bicuspid and Native Aortic Regurgitation
Transcatheter aortic valve implantation (TAVI) is the most frequently performed structural technique in the field of interventional cardiology. Initially, this procedure was only used in patients with severe symptomatic aortic stenosis and prohibitive risk. Now, barely one decade after its introduction, TAVI indications extend to low- and intermediate-risk patients. Despite these advances, several challenging scenarios are still on the periphery of the evidence base for TAVI. These include valve-in-valve procedures, lower-risk patients with bicuspid aortic valve and the treatment of pure aortic regurgitation. Whereas the valve-in-valve indication has expanded rapidly, evidence for the use of TAVI compared with conventional surgery for bicuspid aortic valve is limited, including the best choice of device should TAVI be used. Evidence for TAVI in pure aortic regurgitation is still anecdotal because of suboptimal outcomes. Operators worldwide have described variations in the TAVI procedural technique to achieve commissural alignment and to minimise the rate of pacemaker use through cusp overlap implantation. In light of the potential clinical benefits, this may also be an area of further development. This review aims to discuss the current evidence available supporting the use of TAVI for these new indications
Strategies to Drive Photo-Fenton Process at Mild Conditions for the Removal of Xenobiotics from Aqueous Systems
[EN] The aim of this paper is to provide an overview on the different approaches that can be employed to
drive a photo-Fenton process under mild conditions, using both heterogeneous and homogeneous iron sources.
For this purpose, sections are devoted to the following strategies: a) addition of iron at low concentrations; b) using
the matrix of the effluent in order to avoid deactivation of iron; c) addition of chemical auxiliaries to form
photoactive complexes with iron, such as carboxylates, chelating agents and humic-like macromolecules; d)
strategies leading to the application of heterogeneous photo-Fenton process, by using iron-based solid particles or
by hosting iron on different supports and; e) using heterogeneous iron sources as a reservoir for constant dosing
of homogeneous iron photocatalyst. In particular, the review will focus on the elimination of emerging pollutants
(e.g. drugs, personal care products or pesticides at low concentrations) which are the effluents where applying
neutral photo-Fenton seems especially meaningful, although relevant works with other families of pollutants are
also consideredThis work was performed with the financial of the Marie Sklodowska-Curie Research and Innovation Staff Exchange project funded by the European Commission H2020-MSCA-RISE-2014, within the framework of the research project Mat4treat. Authors also want to thank the financial support of Spanish Ministerio of Economía y Competitividad (TRICERATOPS project and FOTO-CAT excellence network).Santos-Juanes Jordá, L.; Amat Payá, AM.; Arqués Sanz, A. (2017). Strategies to Drive Photo-Fenton Process at Mild Conditions for the Removal of Xenobiotics from Aqueous Systems. Current Organic Chemistry. 21(12):1074-1083. https://doi.org/10.2174/1385272821666170102150337S10741083211
Effect of Salinity on UVA-Vis Light Driven Photo-Fenton Process at Acidic and Circumneutral pH
In the present work, the treatment of a mixture of six emerging pollutants (acetamiprid, acetaminophen, caffeine, amoxicillin, clofibric acid and carbamazepine) by means of photo-Fenton process has been studied, using simulated sunlight as an irradiation source. Removal of these pollutants has been investigated in three different aqueous matrices distinguished by the amount of chlorides (distilled water, 1 g L-1 of NaCl and 30 g L-1 of NaCl) at a pH of 2.8 and 5.0. Interestingly, the presence of 1 g L-1 was able to slightly accelerate the pollutants removal at pH = 5, although the reverse was true at pH = 2.8. This is attributed to the pH-dependent interference of chlorides on photo-Fenton process, that is more acute in an acidic medium. As a matter of fact, the fastest reaction was obtained at pH = 3.5, in agreement with literature results. Monitoring of hydrogen peroxide consumption and iron in solution indicates that interference with chlorides is due to changes in the interaction between iron and the peroxide, rather than a scavenging effect of chloride for hydroxyl radicals. Experiments were also carried out with real seawater and showed higher inhibition than in the NaCl experiments, probably due to the effect of different dissolved salts present in natural water
Mild Fenton Processes for the Removal of Preservatives: Interfering Effect of Methylisothiazolinone (MIT) on Paraben Degradation
[EN] The degradation of various preservatives used in the cosmetics industry, including five parabens and their most employed substitute, methylisothiazolinone (MIT), was investigated. A mild photo-Fenton process was applied using low iron concentrations (5 mg/L) at a pH of five, instead of the traditional acidic value of three. At these conditions, the paraben degradation was very low after one hour of reaction and it was necessary to present humic-like substances (HLS) acting as iron chelators to improve the process. Values obtained when MIT was treated were very low, also in the presence of HLS, indicating that their complexing effect was not acting properly. When MIT was added to the mixture of parabens an inhibitory effect was found in the presence of HLS. A possible complex between iron and MIT was suggested and the studies of hydrogen peroxide consumption and Job's plot technique confirmed this hypothesis. Evidence of the formation of this inactive complex, so far never reported, will be essential in future work when dealing with this compound using Fenton processes. Furthermore, this fact points out the importance of using mixtures of model contaminants instead of a single one or a group of the same family, since their ability to form active or inactive complexes with iron can strongly change the behavior of the whole system.Authors want to acknowledge the financial support of Spanish Ministerio de Ciencia, Innovacion y Universidad (RTI 2018-097997-B-C31, Calypsol Project) and Generalitat Valenciana AICO/2021/014.Duarte-Alvarado, V.; Santos-Juanes Jordá, L.; Arqués Sanz, A.; Amat Payá, AM. (2022). Mild Fenton Processes for the Removal of Preservatives: Interfering Effect of Methylisothiazolinone (MIT) on Paraben Degradation. Catalysts. 12(11):1-16. https://doi.org/10.3390/catal12111390116121
Enantiopure Indolo[2,3-a]quinolizidines: Synthesis and Evaluation as NMDA Receptor Antagonists
Enantiopure tryptophanol is easily obtained from the reduction of its parent natural amino acid trypthophan (available from the chiral pool), and can be used as chiral auxiliary/inductor to control the stereochemical course of a diastereoselective reaction. Furthermore, enantiopure tryptophanol is useful for the syntheses of natural products or biological active molecules containing the aminoalcohol functionality. In this communication, we report the development of a small library of indolo[2,3-a]quinolizidines and evaluation of their activity as N-Methyl D-Aspartate (NMDA) receptor antagonists. The indolo[2,3-a]quinolizidine scaffold was obtained using the following key steps: (i) a stereoselective cyclocondensation of (S)- or (R)-tryptophanol with appropriate racemic -oxoesters; (ii) a stereocontrolled cyclization on the indole nucleus. The synthesized enantiopure indolo[2,3-a]quinolizidines were evaluated as NMDA receptor antagonists and one compound was identified to be 2.9-fold more potent as NMDA receptor blocker than amantadine (used in the clinic for Parkinson's disease). This compound represents a hit compound for the development of novel NMDA receptor antagonists with potential applications in neurodegenerative disorders associated with overactivation of NMDA receptors
Prophylactic percutaneous circulatory support in high risk transcatheter aortic valve implantation
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