Formation and characterization of model cell membranes and their interaction with Magnetic Nanoparticles

In this final master project model cell membranes of a mixture of 1, 2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and cholesterol were transferred onto mica substrates by Langmuir-Blodgett technique (LB) to mimic a real cell membrane. The high quality and chemical structure of the monolayers formed were confirmed by means of Atomic Force Microscopy (AFM) imaging and Contact Angle measurements. A study of the stability of the monolayer in liquid media considering the amphiphilic nature of the compounds was carried out, observing as the monolayer re-assembled into bilayer. This behaviour was explained by means of Force Spectroscopy (FS) studies with a noticeable increase in the breakthrough force values. Furthermore, the deposition of MNPs onto monolayer was carried out by LB in a successful way obtaining a well-covered distribution of MNPs with the final purpose of study the membrane response when it is exposed to alternating magnetic fields (Hyperthermia)

Bottom Effect in Atomic Force Microscopy Nanomechanics

In this work, the influence of the rigid substrate on the determination of the sample Young''s modulus, the so-called bottom-effect artifact, is demonstrated by an atomic force microscopy force-spectroscopy experiment. The nanomechanical properties of a one-component supported lipid membrane (SLM) exhibiting areas of two different thicknesses are studied: While a standard contact mechanics model (Sneddon) provides two different elastic moduli for these two morphologies, it is shown that Garcia''s bottom-effect artifact correction yields a unique value, as expected for an intrinsic material property. Remarkably, it is demonstrated that the ratio between the contact radius (and not only the indentation) and the sample thickness is the key parameter addressing the relevance of the bottom-effect artifact. The experimental results are validated by finite element method simulations providing a solid support to Garcia''s theory. The amphiphilic nature of the investigated material is representative of several kinds of lipids, suggesting that the results have far reaching implications for determining the correct Young''s modulus of SLMs. The generality of Garcia''s bottom-effect artifact correction allows its application to every kind of supported soft film

Modelos de membranas celulares y su interacción con nanopartículas magnéticas

Esta Tesis Doctoral, de carácter multidisciplinar, versa sobre la fabricación de membranas celulares simuladas de fosfolípidos y colesterol. Se han buscado las condiciones para la obtención de películas superficiales muy homogéneas que permitan fácilmente analizar fenómenos superficiales inducidos por la presencia de otros elementos. A estas membranas biomiméticas se les ha incorporado también un glicoesfingolípido conteniendo un grupo azida. El grupo azida permite la realización de química bioortogonal (reacción con un grupo alquino terminal) para la deposición específica de nanopartículas magnéticas (MNPs) convenientemente funcionalizadas. Se ha analizado cómo un campo magnético alterno puede alterar la membrana celular cuando se han incorporado MNPs en su superficie. Se ha concluido que el campo magnético alterno induce un calentamiento local de la membrana decorada con MNPs, modificando su fluidez y generando poros en la misma. También se ha estudiado el efecto de la rugosidad del sustrato en las membranas celulares simuladas mediante un estudio topográfico de microscopía de fuerza atómica y un estudio nanomecánico mediante curvas de fuerzas. Se ha demostrado la influencia de la rigidez de un sustrato en la determinación del módulo de Young de una película blanda y se han aplicado modelos para la corrección de la presencia del sustrato. <br /

Políticas de ocupación, mercado laboral y envejecimiento: iniciativas y buenas prácticas

Pol&iacute;ticas de ocupaci&oacute;n, mercado laboral y envejecimiento: iniciativas y buenas pr&aacute;ctica

Políticas de ocupación, mercado laboral y envejecimiento: iniciativas y buenas prácticas

Pol&iacute;ticas de ocupaci&oacute;n, mercado laboral y envejecimiento: iniciativas y buenas pr&aacute;ctica

Famílies botàniques de plantes medicinals

Facultat de Farmàcia, Universitat de Barcelona. Ensenyament: Grau de Farmàcia, Assignatura: Botànica Farmacèutica, Curs: 2013-2014, Coordinadors: Joan Simon, Cèsar Blanché i Maria Bosch.Els materials que aquí es presenten són els recull de 175 treballs d’una família botànica d’interès medicinal realitzats de manera individual. Els treballs han estat realitzat per la totalitat dels estudiants dels grups M-2 i M-3 de l’assignatura Botànica Farmacèutica durant els mesos d’abril i maig del curs 2013-14. Tots els treballs s’han dut a terme a través de la plataforma de GoogleDocs i han estat tutoritzats pel professor de l’assignatura i revisats i finalment co-avaluats entre els propis estudiants. L’objectiu principal de l’activitat ha estat fomentar l’aprenentatge autònom i col·laboratiu en Botànica farmacèutica

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Formation and characterization of model cell membranes and their interaction with Magnetic Nanoparticles

Proyecto Final del Máster Universitario en Materiales Nanoestructurados para Aplicaciones Nanotecnológicas, Departamento de Química Física de la Universidad de Zaragoza.Understanding the process occurred in cell membranes as well as their interaction with external agents such as Magnetic Nanoparticles (MNPs) is a goal of main importance in biomedicine. In this work model cell membranes of a mixture of 1, 2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and cholesterol were transferred onto mica substrates by Langmuir-Blodgett technique (LB) to mimic a real cell membrane. The high quality and chemical structure of the monolayers formed were confirmed by means of Atomic Force Microscopy (AFM) imaging and Contact Angle measurements. Due to the amphiphilic features of the compounds used in this work, a study of the stability of the monolayer in liquid media was carried out observing as the monolayer re-assembled into bilayer. This behaviour was explained by means of Force Spectroscopy (FS) studies with a noticeable increase in the breakthrough force values. Furthermore, the deposition of MNPs onto monolayer was carried out by LB in a successful way obtaining a well-covered distribution of MNPs with the final purpose of study the membrane response when it is exposed to alternating magnetic fields.Peer Reviewe

Modelos de membranas celulares y su interacción con nanopartículas magnéticas

Esta Tesis Doctoral, de carácter multidisciplinar, versa sobre la fabricación de membranas celulares simuladas de fosfolípidos y colesterol. Se han buscado las condiciones para la obtención de películas superficiales muy homogéneas que permitan fácilmente analizar fenómenos superficiales inducidos por la presencia de otros elementos. A estas membranas biomiméticas se les ha incorporado también un glicoesfingolípido conteniendo un grupo azida. El grupo azida permite la realización de química bioortogonal (reacción con un grupo alquino terminal) para la deposición específica de nanopartículas magnéticas (MNPs) convenientemente funcionalizadas. Se ha analizado cómo un campo magnético alterno puede alterar la membrana celular cuando se han incorporado MNPs en su superficie. Se ha concluido que el campo magnético alterno induce un calentamiento local de la membrana decorada con MNPs, modificando su fluidez y generando poros en la misma. También se ha estudiado el efecto de la rugosidad del sustrato en las membranas celulares simuladas mediante un estudio topográfico de microscopía de fuerza atómica y un estudio nanomecánico mediante curvas de fuerzas. Se ha demostrado la influencia de la rigidez de un sustrato en la determinación del módulo de Young de una película blanda y se han aplicado modelos para la corrección de la presencia del sustrato.Peer reviewe