1,620 research outputs found
La crisis hispano-marroquí de Perejil. Revista de prensa internacional
El desembarco de tropas marroquíes en el islote de Perejil y su posterior desalojo y control por parte de efectivos militares españoles ha desatado una notable cobertura mediática, particularmente desde la contraofensiva española. A continuación se recogen algunos de los comentarios editoriales y la forma en que distintos periódicos no españoles han tratado la crisis hispano-marroquí
Bio-inspired materials for tissue engineering and controlled release of bioactive components
Herbal remedies and natural products have been used since the beginning of human history. A vast number of chemicals derived from plants have been identified over the years, and classified into primary and secondary metabolites. Their latter’s role consists, among other things, on protecting the plants from oxidative stress, microorganism and ultraviolet (UV) irradiation. Rosmarinic acid (RA) is a secondary metabolite which can be found in a variety of families of plants. Arising from its chemical structure, RA possess several desirable properties for the human health such as antioxidant, anti-inflammatory, antiviral and photoprotective. However, its instability, low permeability through biological barriers and scarce water solubility hampers its therapeutic potential. Nanotechnology offers several alternatives to address bioavailability issues. Aside from nanoencapsulation, polymer conjugates are an alternative that have gained a lot of attention over the last decades. Chitosan is one of the most commonly used natural polymers to develop polymer conjugates for the vehiculation of bioactive molecules. In addition to its exceptional functional properties, it is highly abundant polymer in nature and easy to modified, due to the amino groups presents in its structure.
Human skin, the biggest organ in our body, protects us from pathogens, UV light or mechanical injuries. However, as occurs in any other organ, the skin suffers from aging, losing its strength, youth aspect and function. The main factor for premature skin aging is UV irradiation. Under physiological conditions, cells are able to adequate the production of antioxidants to avoid excessive accumulation of reactive oxygen species (ROS). However, after solar irradiation, ROS levels in the skin are highly increased, and as a result, oxidative stress triggers a cascade of biochemical reactions that lead to photoaged skin. In this context, topical application of antioxidants has been proposed as a promising therapy to address this issue. Coenzyme Q10 (CoQ) is one the main cellular antioxidants, involved in mitochondrial function and energy production. Due to its beneficial properties to the human health and its excellent safety records, it is used in more than 200 health food and drug products. Nevertheless, its bioavailability issues derived from its photolability, water insolubility and high molecular weight, shrink its clinical potential. Fortunately, drug delivery systems can be used to overcome this obstacle. Among them, polymer nanoparticles (NPs) possess several desirable properties, including biocompatibility, which means they are unlikely to cause adverse reactions when introduced into living organisms. They also exhibit biodegradability, which means they can break down into smaller, harmless components over time. In addition, their size and surface properties can be carefully controlled, allowing drugs to be delivered directly to specific cells or tissues in the body.
The layer-by-layer (LbL) technique is a methodology employed in a variety of biomedical applications, such as drug delivery, wound healing or surface engineering. It consists on the alternate deposition of polyelectrolytes on either a 2D or 3D complex substrates. As the only requirement is that multipoint interactions, such as electrostatic interactions, exist between the materials used as building blocks, it has become a popular tool to develop new scaffolds for skin applications in form of multilayer systems. Besides, LbL allows to control the structure at the nanometer scale and film’s properties can be tailored changing the preparation conditions. One of the main strategies in the development of novel biomaterials for skin applications, is to provide them with biomimetic features, for example recreating the extracellular matrix (ECM) of cells. For that purpose, polysaccharides, such as chitosan and chondroitin sulphate, are excellent candidates for multilayer films development since there are main ECM components. Furthermore, nanoparticles (NPs) can also be employed as building blocks for multilayer films, enabling local delivery of bioactive molecules with beneficial effects on skin, such as RA or CoQ, improving their bioavailability. In this context, LbL technology can be used to develop advanced chitosan-based scaffolds with a dual role, acting as wound dressings and drug reservoirs, simultaneously.Los remedios a base de hierbas y productos naturales han sido utilizados desde los inicios de la historia de la humanidad. Un amplio número de productos químicos derivados de plantas se han identificado a lo largo de los años y clasificado en metabolitos primarios y secundarios. El rol de estos últimos consiste, entre otras cosas, en proteger a las plantas del estrés oxidativo, microorganismos y radiación ultravioleta (UV). El ácido rosmarínico (RA) es un metabolito secundario que se puede encontrar en una gran variedad de familias de plantas. Debido a su estructura química, el RA posee propiedades deseables para la salud humana como antioxidante, anti-inflamatorio, antiviral o foto-protector. Sin embargo, su inestabilidad, baja permeabilidad a través de barreras biológicas y escasa solubilidad en agua, dificultan su potencial terapéutico. La nanotecnología ofrece varias opciones para tratar problemas de biodisponibilidad. Además de la nanoencapsulación, los conjugados poliméricos son una alternativa que ha ganado mucha atención a lo largo de las últimas décadas. El quitosano es uno de polímeros naturales más comunes para desarrollar conjugados poliméricos para la vehiculización de moléculas bioactivas. Junto con sus excepcionales propiedades funcionales, es un polímero muy abundante en la naturaleza y fácil de modificar gracias a los grupos amino presentes en su estructura.
La piel humana, el órgano más grande de nuestro cuerpo, nos protege contra patógenos, luz UV o lesiones. Sin embargo, como ocurre con cualquier otro órgano, la piel sufre envejecimiento disminuyendo su fortaleza, aspecto joven y funcionalidad. El factor principal en el envejecimiento prematuro de la piel es la radiación UV. En condiciones fisiológicas, las células son capaces de adecuar la producción de antioxidantes para evitar acumulación de especies reactivas de oxígeno (ROS). Sin embargo, después de recibir radiación solar, los niveles de ROS aumentan en gran medida en la piel, y como consecuencia, se inician cascadas de reacciones bioquímicas que dan lugar a envejecimiento de la piel. En este contexto, la aplicación tópica de antioxidantes se ha propuesto como una terapia prometedora para abordar este problema. La coenzima Q10 (CoQ) es uno de los principales antioxidantes celulares que toma parte en el funcionamiento de las mitocondrias y producción de energía. Debido a sus propiedades beneficiosas y seguridad para la salud humana, se utiliza en más de 200 alimentos y productos para la salud. No obstante, sus problemas de biodisponibilidad derivados de su fotolabilidad, insolubilidad en agua y algo peso molecular, reducen su potencial clínico. Por suerte, los sistemas de liberación de fármacos se pueden utilizar para resolver este obstáculo, y entre ellos, las nanopartículas (NPs) poliméricas poseen varias propiedades deseables, como la biocompatibilidad, teniendo una baja probabilidad de causar reacciones adversas al ser introducidas en organismos vivos, o la biodegradabilidad, al poderse descomponer en componentes inocuos más pequeños con el paso del tiempo. Además, las propiedades de superficie de las NPs se pueden controlar y ajustar para conseguir una liberación controlada de fármacos en unas células o tejido específico dentro del organismo.
La técnica de deposición capa a capa es una metodología empleada en una gran variedad de aplicaciones biomédicas, desde la liberación de fármacos o la curación de heridas, a ingeniería de superficies. Consiste en la deposición alterna de polielectrolitos en sustratos 2D o 3D, y el único requisito es la existencia de interacciones multipunto, como interacciones electrostáticas, entre los materiales empleados como bloques de construcción del sistema multicapa. Por este motivo, la deposición capa a capa se ha convertido en una herramienta popular para el desarrollo de nuevos andamios con formas de sistemas multicapa para aplicaciones en piel. Además, esta metodología permite controlar la estructura a escala nanométrica y las propiedades de la película multicapa variando las condiciones de preparación. Una de las principales estrategias en el desarrollo de nuevo biomateriales para aplicaciones de piel, consiste en hacerlos biomiméticos, por ejemplo, recreando la matriz extracelular de las células. Con ese objetivo, los polisacáridos, como el quitosano o el sulfato de condroitina, son excelentes candidatos para desarrollar sistemas multicapa ya que son importantes componentes de la matriz extracelular. Asimismo, las nanopartículas también pueden ser usadas para preparar sistemas multicapa, permitiendo liberar de forma local moléculas bioactivas con propiedades beneficiosas para la piel, como el ácido rosmarínico y la coenzima Q10, mejorando su biodisponibilidad. En este contexto, la tecnología de deposición capa a capa puede ser usada para desarrollar avanzados andamios basados en quitosano con una función doble, actuando como apósitos para heridas y reservorios de fármacos, simultáneamente.Programa de Doctorado en Ciencia y Tecnología Biomédica por la Universidad Carlos III de MadridPresidenta: Florentina Niuris Acosta Contreras.- Secretaria: Olga García Ballesteros.- Vocal: Francisco Martín Goycoole
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Fostering a consciousness of academic success with Latino English language learners in high school: The role self-efficacy and social capital play
The purpose of this study is to suggest ways in which educators can foster a consciousness of academic success with Latino English language learners in high school using self-efficacy and social capital as assets. The concentration of this study is to look at the English language learner population at Vista Valley High School. A total of twelve students participated in this study. Each student will be interviewed twice with at least six additional students being interviewed a third time
Acute myeloid leukemia, secondary to myelodysplastic syndrome, debuting as thrombotic thrombocytopenic purpura: case report
We present a case of myelodysplastic syndrome (MDS) that progressed to acute myeloid leukemia (AML) with changes related to myelodysplasia that presented as thrombotic thrombocytopenic purpura (TTP). After a failure in response to plasmapheresis therapy and a poor long-term prognosis, the family opted for palliative care, the patient dying on the eleventh day of hospitalization. The case is an extremely rare presentation of a rare condition, as it is the second reported case of AML with myelodysplasia-related changes presenting as TTP, and the first reported case of TTP secondary to AML secondary to MDS
Cine y política de oposición en la producción estadounidense tras el 11-S
Los atentados terroristas del 11 de septiembre de 2001 provocaron, entre otras consecuencias, la agitación de la industria cinematográfica estadounidense y el desarrollo de una postura crítica respecto a las decisiones que la administración Bush ha adoptado como respuesta. El activismo ideológico protagonizado por los sectores más liberales de Hollywood se ha visto acompañado en los últimos años de un puñado de filmes que asumen una oposición militante a las tesis gubernamentales: el documental de denuncia, las ficciones políticas y la lectura que el cine bélico hace de la Guerra de Irak son los territorios más representativos de esa línea ideológica
Towards new multivalent supramolecular helical structures based on phthalocyanines for PDT applications
The self-assembly of α-D-glucose octafunctionalized Zn(II) phtalocyanine (ZnPc) in aqueous media has been investigated using different techniques such as UV, CD and diffusion-ordered 1H-NMR spectroscopy (DOSY). The formation of supramolecular columnar helical aggregates with a preferred handedness due to the presence of the sugar moiety has been confirmed by these techniques. Moreover, the stability of the supramolecular polymers formed has been assessed by using pyridine as a zinc ligand, disrupting the aggregates or inducing their formation by dilution of the system.M.G:I. acknowledges the MICINN for his Juan de la Cierva Fellowshi
Semantic Segmentation Using Convolutional Neural Networks for Volume Estimation of Native Potatoes at High Speed
Peru is one of the main producers of a wide variety of native potatoes in the world. Nevertheless, to achieve a competitive export of derived products is necessary to implement automation tasks in the production process. Nowadays, volume measurements of native potatoes are done manually, increasing production costs. To reduce these costs, a deep approach based on convolutional neural networks have been developed, tested, and evaluated, using a portable machine vision system to improve high-speed native potato volume estimations. The system was tested under different conditions and was able to detect volume with up to 90% of accuracy
Investigational Drugs for the Treatment of Postherpetic Neuralgia: Systematic Review of Randomized Controlled Trials
The pharmacological treatment of postherpetic neuralgia (PHN) is unsatisfactory, and
there is a clinical need for new approaches. Several drugs under advanced clinical development are
addressed in this review. A systematic literature search was conducted in three electronic databases
(Medline, Web of Science, Scopus) and in the ClinicalTrials.gov register from 1 January 2016 to
1 June 2023 to identify Phase II, III and IV clinical trials evaluating drugs for the treatment of PHN.
A total of 18 clinical trials were selected evaluating 15 molecules with pharmacological actions on
nine different molecular targets: Angiotensin Type 2 Receptor (AT2R) antagonism (olodanrigan),
Voltage-Gated Calcium Channel (VGCC) 2 subunit inhibition (crisugabalin, mirogabalin and pregabalin),
Voltage-Gated Sodium Channel (VGSC) blockade (funapide and lidocaine), Cyclooxygenase-1
(COX-1) inhibition (TRK-700), Adaptor-Associated Kinase 1 (AAK1) inhibition (LX9211), Lanthionine
Synthetase C-Like Protein (LANCL) activation (LAT8881), N-Methyl-D-Aspartate (NMDA) receptor
antagonism (esketamine), mu opioid receptor agonism (tramadol, oxycodone and hydromorphone)
and Nerve Growth Factor (NGF) inhibition (fulranumab). In brief, there are several drugs in advanced
clinical development for treating PHN with some of them reporting promising results. AT2R
antagonism, AAK1 inhibition, LANCL activation and NGF inhibition are considered first-in-class
analgesics. Hopefully, these trials will result in a better clinical management of PHNTraining University Lecturers program (FPU21/02736)
of the Spanish Ministry of Economy and Competitiveness (MINECO
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