221 research outputs found

    Enhanced performance of gelatin 5-fluorouracil-containing nanoparticles against squamous cell carcinoma in simulated chronic wounds conditions

    Get PDF
    Chronic wounds are considered a silent epidemic affecting a significant fraction of the World population. Their treatment supposes a large fraction of the public spending on the health of developed countries. In chronic wounds secondary to burns, trauma, UV light radiation, and diabetes, among others, the development of squamous cell carcinoma (SCC) has been reported. If detected early, 95% of SCC are most comfortable to be treated and cured; however, 5% of advanced SCC is more dangerous and challenging to treat. It has been reported that the pH value within the wound-milieu influences indirectly and directly all biochemical reactions taking place in this process of healing. Differences in pH values between normal skin and chronic cutaneous wounds could be considered in designing and developing stimuli-responsive nanomaterials. In this work, the anticancer drug 5-fluorouracil (5-FU) inclusion on gelatin-based NPs for SCC treatment has been projected. The present work goal is to prepare and characterize physicochemical and biological properties of new therapeutic-containing NPs for the sustainable delivery of 5-FU under simulated chronic wound conditions. In vitro experiments have been performed to assess the biocompatible character of these gelatin-based NPs in terms of their hemolytic and cytotoxicity properties. Due to hyperglycemia impact on both the chronicity of the wounds and chemotherapy efficacy, cellular responses have been determined under euglycemic and hyperglycemic conditions. In vitro cytotoxicity studies have reported good selective toxicity against the A431 cell line, demonstrating that gelatin-based NPs are promising dual-responsive delivery systems to SCC targeting under simulated chronic wound conditions

    Propuesta del sistema de gestión de seguridad y salud en el trabajo para la facultad de ciencias económicas de la Universidad de Guayaquil bajo los lineamientos del SART.

    Get PDF
    Este documento contiene archivo en PDF.El desarrollo de la presente tesis se basa en el análisis preliminar de los trabajos de titulación de los Ingenieros Industriales Perlaza Nazareno Marcos David, Choez Pibaque Gabriel Ricardo, Plaza Santos Félix Luis, los mismos que al finalizar el diagnóstico del Sistema de Auditorías de Riesgos de Trabajo obtuvieron un puntaje del 11,42%, en la Facultad de Ciencias Económicas de la Universidad de Guayaquil sobre el 80% como mínimo requerido del SART. Partiendo la matriz y el cuadro de estratificación de riesgos se propone la elaboración e implementación de planes de respuestas a Emergencias, vigilancia de la salud de los trabajadores, inspecciones planeadas de seguridad, señalización, implementación de factores de indicadores reactivos y proactivos, información interna y externa, monitoreo de factores de riesgos, desarrollo de competencias, plan de vacunación y otros. Estableciendo un presupuesto global de $ 256.088,20 dólares. Se recomienda la aplicación del método basado en Excel Grafico Radar, para monitorear el detalle de avances del Sistema de Gestión de Prevención de Riesgos, bajo el esquema del SART. El método Radar o también denominado diagrama de araña es una herramienta muy útil para mostrar visualmente los avances entre el estado actual y el futuro de gestión de prevención y presentar claramente las características de desempeño del sistema de gestión de prevención. Esta metodología permite establecer que los avances más significativos en este estudio son la Gestión de los Procedimientos y Programas Operativos Básicos y Administrativa establecidos en el artículo 9 numeral 1 y 4, seguido por la Gestión Técnica y de Talento Humano establecidos en el artículo 9 numeral 2 y 3 y sus literales de la Resolución 333 CD-IESS.The development of this thesis is based on preliminary analysis of the work of certification of Industrial Engineers Perlaza Nazareno Marcos David, Choez Pibaque Gabriel Ricardo, Plaza Santos Félix Luis, the same as at the end of the diagnostic system of Workplace Audits average score of 11,42% , Faculty of Administrative Sciences at the University of Guayaquil on 80% minimum required SART. From the table matrix and risk stratification developing and implementing emergency response plans, monitoring the health of workers, planned safety inspections, signaling factors implementation of proactive and reactive indicators, aims and internal information external, monitoring risk factors, skills development, and other vaccination plan. Establishing an overall budget of 256.088,20 US dollars. The method based on Excel Graphic Radar method is recommended to monitor the detailed progress Management System Risk Prevention, under the scheme of the SART. The Radar method or also called spider diagram is very useful for displaying the progress between the current state and future prevention and management clearly have the characteristics of performance management system prevention tool. This methodology allows for the most significant advances in this study are Management Procedures and Basic Administrative and Operational Programmes set out in Article 9, paragraph 1 and 4, followed by the Technical Management and Talent established in Article 9 paragraph 2 and 3 and their literal Resolution 333 CD-IESS

    Regenerable Superhydrophobic Coatings for Biomedical Fabrics

    Get PDF
    Coatings with high water repellence represent a promising field for biomedical applications. Superhydrophobicity (SH) can be used for preventing adhesion, controlling cell deposition, and spreading by inhibition of adsorption processes at liquid-solid interfaces. The recyclability of medical aids like fabrics can open the way for lower cost and more environmentally-friendly solutions. In this case, two different coatings form recyclable and low global warming potential materials and green solvents have been prepared and characterized based on their wettability properties. The resulting substrates have been used for the adhesion and spreading of representative skin cell lines, both tumoral and non-tumoral, showing a strong decrease in cell viability with values <10%. The coated substrates showed a complete recovery on initial SH properties after rinsing with suitable solvents

    Mammalian Cell Behavior on Hydrophobic Substrates: Influence of Surface Properties

    Get PDF
    The influence of different surface properties holding to a modification of the substrate towards hydrophobic or superhydrophobic behavior was reviewed in this paper. Cell adhesion, their communication, and proliferation can be strongly manipulated, acting on interfacial relationship involving stiffness, surface charge, surface chemistry, roughness, or wettability. All these features can play mutual roles in determining the final properties of biomedical applications ranging from fabrics to cell biology devices. The focus of this work is the mammalian cell viability in contact with moderate to highly water repellent coatings or materials and also in combination with hydrophilic areas for more specific application. Few case studies illustrate a range of examples in which these surface properties and design can be fruitfully matched to the specific aim

    Acoso escolar: relación con sentimiento de soledad y perfeccionismo positivo en adolescentes

    Get PDF
    En esta investigación nos planteamos como hipótesis que el maltrato físico y psicológico es únicamente un componente del bullying, que otros componentes son el rechazo de iguales y la soledad por separación significativa. Como segunda hipótesis planteamos que el bullying se dirige principalmente hacia adolescentes que destacan por tener un nivel superior de perfeccionismo positivo. Otros objetivos fueron conocer la incidencia del acoso en la muestra estudiada y averiguar si existen diferencias por razón de género en las variables estudiadas. Participaron 167 escolares de 12 a 16 años (varones = 46%). Se aplicaron cuestionarios de autoinforme. Los resultados confirman la hipótesis de que los adolescentes con mayor sentimiento de soledad y rechazados por sus iguales son los más propensos a sufrir el maltrato de acosadores. La segunda hipótesis se confirma parcialmente: los chicos acosados no son más perfeccionistas que los no acosados, aunque esta relación si se produce en las chicas acosadas que sí tienen un mayor perfeccionismo en “sensibilidad a los errores”. No aparecen diferencias de género en la frecuencia del acoso. Y se confirma que en esta población más del 5% de los adolescentes percibir acoso en un grado relativamente grave.In this study, we hypothesized that physical and psychological abuse is only one component of bullying; other components are peer rejection and loneliness. As second hypothesis proposed was that bullying is mainly focused towards teens having higher level of positive perfectionism. Others objectives were: to determine the incidence of harassment in the sample and find gender differences. Participants were 167 schoolchildren (12-16 years; males = 46%). Self-report questionnaires were applied. The results confirm the hypothesis that adolescents with greater feelings of loneliness and rejected by their peers are more probable to suffer abuse. The second hypothesis was partially confirmed: the boys harassed are not perfectionists that none harassed, while this relationship occurs in girls who do have a higher positive perfectionism. No gender differences appear in the frequency of harassment. In this population confirmed that 5.4 percent of adolescents perceived harassment in a relatively high degree.peerReviewe

    Jornadas escolares

    Get PDF
    S

    Cytotoxic Assessment of 3,3-Dichloro-β-Lactams Prepared through Microwave-Assisted Benzylic C-H Activation from Benzyl-Tethered Trichloroacetamides Catalyzed by RuCl2(PPh3)3

    Full text link
    Natural and synthetic ß -lactam derivatives constitute an interesting class of compounds due to their diverse biological activity. Mostly used as antibiotics, they were also found to have antitubercular, anticancer and antidiabetic activities, among others. In this investigation, six new 3,3-dichloro-ß -lactams prepared in a previous work were evaluated for their hemolytic and cytotoxic properties. The results showed that the proposed compounds have non-hemolytic properties and exhibited an interesting cytotoxic activity toward squamous cell carcinoma (A431 cell line), which was highly dependent on the structure and concentration of these -lactams. Among the molecules tested, 2b was the most cytotoxic, with the lowest IC50 values (30-47 µg/mL) and a promising selectivity against the tumor cells compared with non-tumoral cells

    Mammalian cell viability on hydrophobic and superhydrophobic fabrics

    Get PDF
    fecting its growth, survival and also for its communication with other cells on fabrics. The combination of low surface energy and a specific surface morphology (micro/nano-roughness) leads to significantly less wettable surfaces, known as superhydrophobic characterized by high contact angle above 150° and a very small hysteresis. Such high water repellent coatings feature small area available to be exploited in many applications where interactions with aqueous environment are strongly to be avoided. In this work, the authors have investigated the influence of coating polyester fabric at different degree of hydrophobicity by mixed organicinorganic coating with moderated to highly water repellence. Depending on the coating composition and structure, the hydrophobicity of the fabric can be finely modulated by an easy-to-prepare method applicable to commercial, low cost fabric substrates providing advanced performance. In vitro experiments have been performed in order to establish the influence of surface modification on adhesion of representative model mammalian cell lines such as 3T3 fibroblasts, HaCaT keratinocytes and HeLa epithelial carcinoma cells. The obtained results suggested that, in addition to the chemistry and morphology of the coating, the characteristics of the substrate are important parameters on the final cell viabilities
    corecore