26 research outputs found

    Starch Modified With Chitosan and Reinforced With Feather Keratin Materials Produced by Extrusion Process: An Alternative to Starch Polymers

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    They also reached up to 3800% and 3150% in maximum strength, respectively, compared to the matrix. The lysozyme test showed relevant changes in the degradability rate, because the weight loss of the films at 3 weeks decreased from 53% for starch-chitosan matrix and up to 34% for composites with 5wt% of modified quill. The results corroborated that chicken feather materials can be useful for the development of a manufacturing process for starch composites, and the decomposition of starch-chitosan composites can be controlled depending on the content and type of keratin.Starch (potato), chitosan, and feather keratin are used for processing biodegradable films produced by extrusion. The morphology of the films is examined with a scanning electron microscope and showed the excellent dispersion of keratin. The dispersion is the result of compatibility between the polysaccharides and proteins, as well as the proper operation of the extrusion process. Water solubility of the starch-chitosan films decreased with an increase of keratin materials. The storage modulus increased up to 137% for the composites with unmodified ground quill, and by 192% for composites with modified ground quill. In a tensile test, the composites with unmodified and modified quill reached outstanding increments up to 8160 and 7250% in elastic modulus, respectively, compared to the matrixUniversidad Autonoma del Estado de Mexico Tecnologico Nacional de Mexico Universidad Nacional Autonoma de Mexico Universidad Autonoma de Cd. Juare

    Tumor-Induced CD8+ T-Cell Dysfunction in Lung Cancer Patients

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    Lung cancer is the leading cause of cancer deaths worldwide and one of the most common types of cancers. The limited success of chemotherapy and radiotherapy regimes have highlighted the need to develop new therapies like antitumor immunotherapy. CD8+ T-cells represent a major arm of the cell-mediated anti-tumor response and a promising target for developing T-cell-based immunotherapies against lung cancer. Lung tumors, however, have been considered to possess poor immunogenicity; even so, lung tumor-specific CD8+ T-cell clones can be established that possess cytotoxicity against autologous tumor cells. This paper will focus on the alterations induced in CD8+ T-cells by lung cancer. Although memory CD8+ T-cells infiltrate lung tumors, in both tumor-infiltrating lymphocytes (TILs) and malignant pleural effusions, these cells are dysfunctional and the effector subset is reduced. We propose that chronic presence of lung tumors induces dysfunctions in CD8+ T-cells and sensitizes them to activation-induced cell death, which may be associated with the poor clinical responses observed in immunotherapeutic trials. Getting a deeper knowledge of the evasion mechanisms lung cancer induce in CD8+ T-cells should lead to further understanding of lung cancer biology, overcome tumor evasion mechanisms, and design improved immunotherapeutic treatments for lung cancer

    Apoyo social y autoestima en el alumnado universitario: implicaciones para la calidad del aprendizaje

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    La comprensión del proceso de adaptación del estudiantado de nuevo ingreso a la Educación Superior ha cobrado relevancia, debido a la necesidad de reducir el fracaso académico y el abandono prematuro. La investigación al respeto ha venido centråndose en analizar qué variables se encuentran relacionadas con la adaptación universitaria y el rendimiento académico. Entre estas variables, el presente estudio ha seleccionado la autoestima y el apoyo social, cuya relación directa con el éxito académico ha sido ampliamente fundamentada. A través de un estudio descriptivo y correlacional se caracteriza el perfil psicosocial del estudiantado de nuevo ingreso y se analiza la relación entre las variables citadas. La muestra asciende a 750 estudiantes de nuevo ingreso de la Universidad de Sevilla. Los resultados muestran que los estudiantes de primer año acceden a la Educación Superior con unos niveles altos de autoestima y apoyo social. Ambas variables mostraron una relación moderada de signo positivo. A partir de estos resultados se derivan algunas recomendaciones con el objetivo de que desde las Universidades se favorezca el apoyo social de los estudiantes de nuevo ingreso y su autoestima, facilitando así la adaptación al contexto universitario y la mejora de su aprendizaje

    Expectativas del alumnado universitario sobre el logro de una formaciĂłn de calidad para el empleo

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    La relevancia que ha ido adquiriendo el concepto de empleabilidad dentro de la EducaciĂłn Superior ha estado marcada por su inclusiĂłn dentro de los objetivos prioritarios de las polĂ­ticas educativas europeas, erigiĂ©ndose en un elemento de calidad para las universidades. El presente estudio se centra en conocer quĂ© expectativas poseen los estudiantes de nuevo ingreso, al inicio de su primer curso universitario, acerca de las oportunidades que la EducaciĂłn Superior les brindarĂĄ para lograr una formaciĂłn de calidad que contribuya a garantizar su empleabilidad. Para ello, hemos contado con una muestra de 940 estudiantes de las cinco ĂĄreas de enseñanza universitaria. Las expectativas del alumnado fueron obtenidas mediante encuesta. El anĂĄlisis de los datos se apoyĂł en el cĂĄlculo de estadĂ­sticos descriptivos y en el anĂĄlisis de la varianza, con estimaciĂłn del tamaño del efecto mediante eta cuadrado parcial. Los resultados muestran en general unas expectativas altas en cuanto a la formaciĂłn para el empleo y la carrera, aunque con claras diferencias segĂșn ĂĄreas de enseñanza. Tras reflexionar sobre las expectativas comparativamente menos altas que se registran para el alumnado de Artes y Humanidades, se proponen medidas orientadas a responder a las expectativas de los estudiantes e incrementar la calidad de la educaciĂłn que se les proporciona en las instituciones universitaria

    Dietary Compounds as Epigenetic Modulating Agents in Cancer

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    Epigenetic mechanisms control gene expression during normal development and their aberrant regulation may lead to human diseases including cancer. Natural phytochemicals can largely modulate mammalian epigenome through regulation of mechanisms and proteins responsible for chromatin remodeling. Phytochemicals are mainly contained in fruits, seeds, and vegetables as well as in foods supplements. These compounds act as powerful cellular antioxidants and anti-carcinogens agents. Several dietary compounds such as catechins, curcumin, genistein, quercetin and resveratrol, among others, exhibit potent anti-tumor activities through the reversion of epigenetic alterations associated to oncogenes activation and inactivation of tumor suppressor genes. In this review, we summarized the actual knowledge about the role of dietary phytochemicals in the restoration of aberrant epigenetic alterations found in cancer cells with a particular focus on DNA methylation and histone modifications. Furthermore, we discussed the mechanisms by which these natural compounds modulate gene expression at epigenetic level and described their molecular targets in diverse types of cancer. Modulation of epigenetic activities by phytochemicals will allow the discovery of novel biomarkers for cancer prevention, and highlights its potential as an alternative therapeutic approach in cancer

    Compromising between European and US allergen immunotherapy schools: Discussions from GUIMIT, the Mexican immunotherapy guidelines

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    Background: Allergen immunotherapy (AIT) has a longstanding history and still remains the only disease-changing treatment for allergic rhinitis and asthma. Over the years 2 different schools have developed their strategies: the United States (US) and the European. Allergen extracts available in these regions are adapted to local practice. In other parts of the world, extracts from both regions and local ones are commercialized, as in Mexico. Here, local experts developed a national AIT guideline (GUIMIT 2019) searching for compromises between both schools. Methods: Using ADAPTE methodology for transculturizing guidelines and AGREE-II for evaluating guideline quality, GUIMIT selected 3 high-quality Main Reference Guidelines (MRGs): the European Academy of Allergy, Asthma and Immunology (EAACI) guideines, the S2k guideline of various German-speaking medical societies (2014), and the US Practice Parameters on Allergen Immunotherapy 2011. We formulated clinical questions and based responses on the fused evidence available in the MRGs, combined with local possibilities, patient's preference, and costs. We came across several issues on which the MRGs disagreed. These are presented here along with arguments of GUIMIT members to resolve them. GUIMIT (for a complete English version, see Supplementary data) concluded the following: Results: Related to the diagnosis of IgE-mediated respiratory allergy, apart from skin prick testing complementary tests (challenges, in vitro testing and molecular such as species-specific allergens) might be useful in selected cases to inform AIT composition. AIT is indicated in allergic rhinitis and suggested in allergic asthma (once controlled) and IgE-mediated atopic dermatitis. Concerning the correct subcutaneous AIT dose for compounding vials according to the US school: dosing tables and formula are given; up to 4 non-related allergens can be mixed, refraining from mixing high with low protease extracts. When using European extracts: the manufacturer's indications should be followed; in multi-allergic patients 2 simultaneous injections can be given (100% consensus); mixing is discouraged. In Mexico only allergoid tablets are available; based on doses used in all sublingual immunotherapy (SLIT) publications referenced in MRGs, GUIMIT suggests a probable effective dose related to subcutaneous immunotherapy (SCIT) might be: 50–200% of the monthly SCIT dose given daily, maximum mixing 4 allergens. Also, a table with practical suggestions on non-evidence-existing issues, developed with a simplified Delphi method, is added. Finally, dissemination and implementation of guidelines is briefly discussed, explaining how we used online tools for this in Mexico. Conclusions: Countries where European and American AIT extracts are available should adjust AIT according to which school is followed

    Anafilaxia en niños y adultos: prevención, diagnóstico y tratamiento

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    La anafilaxia es una condiciĂłn que requiere asistencia inmediata para su resoluciĂłn, se puede presentar en diferentes entornos: consultorio, hospital, escuela, hogar o en algĂșn otro espacio pĂșblico. La informaciĂłn aquĂ­ contenida forma parte de lineamientos conocidos sobre prevenciĂłn, diagnĂłstico y tratamiento. Se abordan aspectos epidemiolĂłgicos, desencadenantes, factores de riesgo y cofactores; se explican de una manera didĂĄctica los mecanismos fisiopatolĂłgicos que se traducen en fenotipos de presentaciĂłn. Se enfatiza el diagnĂłstico clĂ­nico con base en criterios ya establecidos, se mencionan clasificaciones para evaluar la gravedad de la reacciĂłn, asĂ­ como el rol de las pruebas clĂ­nicas o de laboratorio. Como aspectos de relevancia, se abordan el tratamiento de primera elecciĂłn con adrenalina, instrucciones sobre autoinyectores y diferentes elementos para el tratamiento complementario y de segunda elecciĂłn. TambiĂ©n se refieren aspectos a considerar al dar de alta a un paciente y medidas de seguimiento, con un Ă©nfasis preventivo en la comunidad. Finalmente, se menciona el abordaje en el consultorio de alergia para decidir sobre opciones de inmunomodulaciĂłn. ABSTRACT Anaphylaxis is a condition that requires immediate assistance for its resolution, it can occur in different settings: office, hospital, school, home or some other public space. The information contained herein forms part of known guidelines on prevention, diagnosis and treatment. Epidemiological aspects, triggers, risk factors and co-factors are addressed; physiopathological mechanisms that are translated into presentation phenotypes are explained in a didactic way. Clinical diagnosis is emphasized based on established criteria, classifications are mentioned to evaluate the severity of the reaction, as well as the role of clinical or laboratory tests. As relevant aspects, the first choice treatment with adrenaline, instructions on auto-injectors and different elements for the complementary and second choice treatment are dealt with. They also refer to aspects to consider when discharging a patient and followup measures, with a preventive emphasis on the community. Finally, the allergy clinic approach to deciding on immunomodulation options is mentione

    GUIMIT 2019, Guía mexicana de inmunoterapia. Guía de diagnóstico de alergia mediada por IgE e inmunoterapia aplicando el método ADAPTE

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