50 research outputs found
Crosstalk characterization of fabrics elaborated with conductive yarns
The electrical characterization of crosstalk of fabrics elaborated with conductive yarns is investigated. The impact of the source, victim and ground traces location is reported. The experimental results show that the crosstalk in fabrics is higher in comparison with other conductive media. Nevertheless, the results show that the standard strategies to reduce the coupling between lines can be used on fabrics. Doing this, fabrics elaborated with conductive yarns can be used as a conductive media for digital buses, which can help to improve the integration of electronic devices in textile.Peer ReviewedPostprint (author's final draft
Electrospun PLLA membranes for caffeine delivery: diffusional approach
One of the great advantages of electrospun fibers is the large tridimensional area produced, capable of storing any type of material. The aim of our investigation is to study the electrospinning technique to produce polymer membranes for drug delivery applications, given their large surface area and ability to transport a bioactive compound. A mathematical modeling of the delivery system kinetics was also studied to find the mechanism that controls the releasing process. Results showed that electrospinning could provide regular and smooth membranes suitable for drug delivery processes. The mathematical modeling also proved that thicker PLLA membranes exhibited a Fickian diffusion behavior during the drug transport, presenting better control in drug delivery processesPostprint (published version
Tissue compatibility of SN-38-loaded anticancer nanofiber matrices
Delivery of chemotherapy in the surgical bed has shown preclinical activity to control cancer progression upon subtotal resection of pediatric solid tumors, but whether this new treatment is safe for tumor-adjacent healthy tissues remains unknown. Here, Wistar rats are used to study the anatomic and functional impact of electrospun nano¿ber matrices eluting SN-38—a potent chemotherapeutic agent—on several body sites where pediatric tumors such as neuroblastoma, Ewing sarcoma, and rhabdomyosarcoma arise. Blank and SN-38-loaded matrices embracing the femoral neurovascular bundle or in direct contact with abdominal viscera (liver, kidney, urinary bladder, intestine, and uterus) are placed. Foreign body tissue reaction to the implants is observed though no histologic damage in any tissue/organ. Skin healing is normal. Tissue reaction is similar for SN-38-loaded and blank matrices, with the exception of the hepatic capsule that is thicker for the former although within the limits consistent with mild foreign body reaction. Tissue and organ function is completely conserved after local treatments, as assessed by the rotarod test (forelimb function), hematologic tests (liver and renal function), and control of clinical signs. Overall, these ¿ndings support the clinical translation of SN-38-loaded nano¿ber matrices to improve local control strategies of surgically resected tumorsPostprint (author's final draft
Spatiotemporal Characteristics of the Largest HIV-1 CRF02_AG Outbreak in Spain: Evidence for Onward Transmissions
Background and Aim: The circulating recombinant form 02_AG (CRF02_AG) is the predominant clade among the human immunodeficiency virus type-1 (HIV-1) non-Bs with a prevalence of 5.97% (95% Confidence Interval-CI: 5.41–6.57%) across Spain. Our aim was to estimate the levels of regional clustering for CRF02_AG and the spatiotemporal characteristics of the largest CRF02_AG subepidemic in Spain.Methods: We studied 396 CRF02_AG sequences obtained from HIV-1 diagnosed patients during 2000–2014 from 10 autonomous communities of Spain. Phylogenetic analysis was performed on the 391 CRF02_AG sequences along with all globally sampled CRF02_AG sequences (N = 3,302) as references. Phylodynamic and phylogeographic analysis was performed to the largest CRF02_AG monophyletic cluster by a Bayesian method in BEAST v1.8.0 and by reconstructing ancestral states using the criterion of parsimony in Mesquite v3.4, respectively.Results: The HIV-1 CRF02_AG prevalence differed across Spanish autonomous communities we sampled from (p < 0.001). Phylogenetic analysis revealed that 52.7% of the CRF02_AG sequences formed 56 monophyletic clusters, with a range of 2–79 sequences. The CRF02_AG regional dispersal differed across Spain (p = 0.003), as suggested by monophyletic clustering. For the largest monophyletic cluster (subepidemic) (N = 79), 49.4% of the clustered sequences originated from Madrid, while most sequences (51.9%) had been obtained from men having sex with men (MSM). Molecular clock analysis suggested that the origin (tMRCA) of the CRF02_AG subepidemic was in 2002 (median estimate; 95% Highest Posterior Density-HPD interval: 1999–2004). Additionally, we found significant clustering within the CRF02_AG subepidemic according to the ethnic origin.Conclusion: CRF02_AG has been introduced as a result of multiple introductions in Spain, following regional dispersal in several cases. We showed that CRF02_AG transmissions were mostly due to regional dispersal in Spain. The hot-spot for the largest CRF02_AG regional subepidemic in Spain was in Madrid associated with MSM transmission risk group. The existence of subepidemics suggest that several spillovers occurred from Madrid to other areas. CRF02_AG sequences from Hispanics were clustered in a separate subclade suggesting no linkage between the local and Hispanic subepidemics
DISSENY D'ESTRUCTURES LINEALS I LAMINARS NO TEIXIDES (Examen 1r quadrimestre, 1r parcial)
DISSENY D'ESTRUCTURES LINEALS I LAMINARS NO TEIXIDES (Examen 1r quadrimestre, 2n parcial)
DISSENY D'ESTRUCTURES LINEALS I LAMINARS NO TEIXIDES (Examen 1r quadrimestre, 1r parcial)
Aportaciones al desarrollo preclínico de un medicamento oncológico infantil con excipiente o soporte textil
The world of technical textiles is present every day in more sectors. In the work presented, a new facet of textile materials has been shown, textiles as a drug excipient and functional matrix.
It is known that electro-spinning technology has opened up a range of possibilities in the field of medical textiles. However, the environment and the requirements of the pharmaceutical sector make the implementation of any new product a long and expensive job.
This work is part of a project to develop a new medicine for both adult and paediatric cancer use. The drug that is developed uses as excipient and support matrix a non-woven formed with nanofibers made by the electro-spinning technique. During the nonwoven formation process, the active ingredient (API) is integrated into the structure. In this way, a very effective drug is produced for its intended use.
The present work focuses on finding solutions that help the development of this drug by adapting the textile production of nanofibers to the level of quality required for the production of a drug intended to be implanted inside a person. For this reason, a search has been made on the current state of the art of nanofiber production technologies. This has been done in order to ensure the production and scaling process in a future implementation in the development of the product at the commercial level.
From a development point of view, the mode of deposition of the nanofiber beam in the collector has been analysed. Theoretical concepts of a textile nature have been developed such as fibre count, deposition rate, total draw and polymer adapted to the electro-spinning technique. With these developments, new studies may be carried out that include these variables to gain an in-depth understanding of their influence on the structure of fibres and their properties, as is the case with fibres produced by conventional textile filament extrusion techniques.
Moreover, an analysis was carried out with its corresponding validation, using finite element modelling (FEM) of the electrostatic field in the electrospinning process. Thanks to this analysis, the nature of the sources of disturbance of the electrospinning beam that affect the homogeneity and therefore the quality of the generated non-tissue has been known.
As a result of the knowledge acquired with the FEM analysis, an element has been developed that guarantees the homogeneity of the fibres throughout the entire non-woven production width, thus allowing to maximize quality and production area.El mundo de los textiles de técnicos está presente cada día en más sectores. En el trabajo presentado se ha mostrado una nueva faceta de los materiales textiles: los textiles como excipiente de medicamento. Es conocido que la tecnología de electrohilatura ha abierto un abanico de posibilidades en el sector de los textiles de uso médico. Sin embargo, el entorno y los requisitos del sector farmacéutico hacen que la implementación de cualquier nuevo producto sea un trabajo largo y costoso. Este trabajo se enmarca dentro de un proyecto de desarrollo de un nuevo medicamento de uso oncológico tanto adulto como pediátrico. El fármaco que se desarrolla usa como excipiente un no tejido formado con nanofibras elaboradas por la técnica de electrohilatura. Durante el proceso de formación del no tejido se integra el principio activo (API) en la estructura. De este modo, se produce un fármaco muy eficaz para el uso al que va destinado. El presente trabajo se centra en buscar soluciones que ayuden al desarrollo de este fármaco mediante la adecuación de la producción textil de nanofibras al nivel de calidad requerido para la producción de un fármaco destinado a ser implantado dentro de una persona. Por este motivo, se ha realizado una búsqueda en el estado actual de la técnica de las tecnologías de producción de nanofibras, con objeto de asegurar el proceso de producción y escalado en una futura implementación en el desarrollo del producto a nivel de comercial. Bajo un punto de vista de desarrollo, se ha analizado el modo de deposición del haz de nanofibras en el colector. En este apartado se han desarrollado conceptos teóricos de naturaleza textil como son: título de fibra, velocidad de deposición, estiraje total y de polímero adaptados a la técnica de electrohilatura. Con estos desarrollos se podrán realizar nuevos estudios que incluyan estas variables para conocer en profundidad la influencia de estos en la estructura de las fibras y sus propiedades, tal y como sucede con las fibras producidas por las técnicas convencionales de extrusión de filamentos textiles. Paralelamente, se ha realizado un análisis con su correspondiente validación mediante modelización por elementos finitos (FEM) del campo electroestático en el proceso de electrohilatura. Gracias a este análisis, se ha conocido la naturaleza de las fuentes de perturbación del haz de electrohilatura que afectan la homogeneidad y por tanto la calidad del no tejido generado. Fruto de los conocimientos adquiridos con el análisis FEM, se ha desarrollado un elemento que permite garantizar la homogeneidad de las fibras en todo el ancho de producción del no tejido, permitiendo de este modo maximizar la calidad y la superficie de producción.Postprint (published version