1,094 research outputs found

    Study of the mechanism of cell death caused by peptides targeting CD47 in leukemia cell lines.

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    CD47 activation through the C-terminus of thrombospondin-1 or its derived peptides (4N1K and PKHB1) induce regulated cell death (RCD) in several types of cancer. Recently, it was demonstrated that PKHB1, the first serum-stable CD47 agonist peptide, induce caspase-independent, calcium-dependent RCD in CLL cells, even in those resistant to conventional therapy. Therefore, the objective of the present work was to study the PKHB1-induced cell death mechanism in other types of leukemia. To that end, cell death induction was evaluated by flow cytometry, analyzing phosphatidilserine exposure (Ann-V) and plasma membrane permeability (PI), as well as caspase dependance (inhibitor Q-VD-OPH) or calcium dependance (BAPTA, calcium chelator). The results show that PKHB1 is a better inductor of cell death, compared to 4N1K, and it is selective to different types of leukemia (MEC-1, CEM, Junket, K562, HL-60, L5178Y-R), since it does not kill human peripheral mononuclear cells, nor cells derived from lymphoid organs of healthy mice. PKHB1-induced killing is caspase-independent in all cases. Additionally, in CEM (human T lymphoblasts of acute lymphocytic leukemia, the principal type of childhood cancer) and L5178Y-R (murine T lymphoblasts) cells, death is not modulated by co-culture with chemoprotective bone marrow stromal cells; calcium chelation, however, inhibits PKHB1-induced cell death. Together, the results indicate that PKHB1 is effective in different types of leukemia, and induce caspase-independent, microenvironment-independent calcium-dependent RCD, in leukemic T lymphocytes. These results suggest that PKHB1-induced RCD could be conserved in different types of leukemia, and set the basis for further studies on murine models

    Construcción metodológica de la aplicabilidad de la teoría de la justicia de John Rawls en el marco de la distribución de la riqueza en Colombia

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    La distribución de la riqueza es uno de presupuestos elementales que devienen de la estructura de la hacienda pública para la consecución de los fines esenciales de un Estado. En ese orden de ideas, la repartición de los recursos se materializa en la formulación de los presupuestos anuales ya sea nacionales, regionales o locales. Sin embargo, en la práctica se tiene que la distribución de los recursos no siempre implica que se vea reflejado en las necesidades de los ciudadanos, como quiera que la importancia y la prioridad está sujeta a la coyuntura política, económica y social que se encuentre atendiendo el Gobierno Nacional. El problema que suscita a partir de allí es, si la distribución de la riqueza no se aplica en una masa universal, sino en focos específicos, ¿cómo se puede lograr la justicia, que se supone se persigue como fin indispensable de un Estado? Por otro lado, Rawls propone un modelo de justicia como equidad en el que los bienes primarios redunden especialmente entre los menos aventajados, como solución a la regla de Pareto. Teniendo en cuenta estos postulados, la presente ponencia se construye con el fin de presentar un primer modelo de metodología en el que sea aplicable la teoría de la justicia de Rawls en la distribución de la riqueza, como mecanismo necesario para la consecución de los fines del Estado, sin desconocer el modelo económico o la estructura misma del Estado.Facultad de Humanidades y Ciencias de la Educació

    Multiple feature models for image matching

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    The common approach to image matching is to detect spatial features present in both images and create a mapping that relates both images. The main draw back of this method takes place when more than one matching is likely. A first simplification to this ambiguity is to represent with apara-metric model the point locus where the matching is highly likely,and then use a POCS(projection on to convex sets)procedure combined with Tikhonov regularization that results in the mapping vectors. However,if there is more than one model perpixel,the regularization and constrainforcing process faces a multiplechoice dilemma that has no easy solution. This work proposes a frame work to overcome this draw back: the combined projection over multiple models base don the norm of the projection–pointdis-tance. This approach is tested on a stereo-pair that presents multiple choices of similar likelihood.This work is partially supported by the Spanish Ministerio de Ciencia y Tecnología,under grant TIC2002-03033

    An Innovative Strategy Based on Secure Element for Cyber–Physical Authentication in Safety-Critical Manufacturing Supply Chain

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    This research has been founded by the European Union’s Horizon 2020 Research and Innovation program under grant agreement No. 871518, a project named, A COmprehensive cyber-intelligence framework for resilient coLLABorative manufacturing Systems, COLLABS [55].The accurate tracking of every production step and related outcome in a supply chain is a stringent requirement in safety-critical sectors such as civil aviation. In such a framework, trusted traceability and accountability can be reliably and securely managed by means of blockchain-based solutions. Unfortunately, blockchain cannot guarantee the provenance and accuracy of the stored information. To overcome such a limitation, this paper proposes a secure solution to strongly rely on the tracking information of the physical assets in the supply chain. The proposed solution exploits Hardware Security Modules (HSMs) to provide required cryptographic primitives through a Near-Field Communication (NFC) connection. In our approach, each transfer of the assets is authenticated, verified, and recorded in the blockchain through the HSM. Transaction entries are signed, thus providing a guarantee of ownership and authenticity. The proposed infrastructure has been subject of an exhaustive security analysis and proved resilient against counterfeiting attempts, stakeholder repudiations, and misleading information.Horizon 2020 Framework Programme 871518 H202

    Integration Host Factor (IHF) binds to the promoter region of the phtD operon involved in phaseolotoxin synthesis in P. syringae pv. phaseolicola NPS3121

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    <p>Abstract</p> <p>Background</p> <p><it>Pseudomonas syringae </it>pv. phaseolicola, the causal agent of halo blight disease in beans, produces a toxin known as phaseolotoxin, in whose synthesis participate a group of genes organized within the genome in a region known as the "Pht cluster". This region, which is thought to have been acquired by horizontal gene transfer, includes 5 transcriptional units, two monocistronic (<it>argK, phtL</it>) and three polycistronic (<it>phtA, phtD, phtM</it>), whose expression is temperature dependent. So far, the regulatory mechanisms involved in phaseolotoxin synthesis have not been elucidated and the only well-established fact is the requirement of low temperatures for its synthesis. In this work, we searched for regulatory proteins that could be involved in phaseolotoxin synthesis, focusing on the regulation of the <it>phtD </it>operon.</p> <p>Results</p> <p>In this study we identified the global regulator IHF (Integration Host Factor), which binds to the promoter region of the <it>phtD </it>operon, exerting a negative effect on the expression of this operon. This is the first regulatory protein identified as part of the phaseolotoxin synthesis system. Our findings suggest that the Pht cluster was similarly regulated in the ancestral cluster by IHF or similar protein, and integrated into the global regulatory mechanism of <it>P. syringae </it>pv. phaseolicola, after the horizontal gene transfer event by using the host IHF protein.</p> <p>Conclusion</p> <p>This study identifies the IHF protein as one element involved in the regulation of phaseolotoxin synthesis in <it>P. syringae </it>pv. phaseolicola NPS3121 and provides new insights into the regulatory mechanisms involved in phaseolotoxin production.</p

    Síndrome de reperfusión en el paciente quirúrgico : fisiopatología, manifestaciones clínicas y nuevas alternativas de manejo

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    Con el objetivo de describir los eventos fisiopatológicos, las manifestaciones clínicas y las estrategias de manejo del síndrome isquemia-reperfusión en el paciente quirúrgico, se realizó una revisión de la literatura. Teniendo en cuenta la complejidad de los pacientes sometidos a cirugías mayores, las víctimas de trauma mayor y quemaduras, una comprensión adecuada de los eventos subyacentes a nivel celular y humoral, pero fundamentalmente de todos aquellos relacionados con el aparato energético permiten enfrentar y prevenir oportunamente las consecuencias que implican el agotamiento de la mitocondria y en general del funcionamiento celular. Las estrategias de tratamiento frecuentemente se refieren en un amplio sentido a la forma de reanimación utilizada, líquidos, terapia transfusional, nutrición y soporte general en la unidad de cuidado intensivo. No obstante más allá de estas estrategias convencionales, hoy en día existe una creciente literatura que en buena parte se dirige a la comprensión de procesos específicos y tratamientos que son objeto de estudio y experimentación. En este artículo se pretende revisar específicamente estas estrategias de tratamiento, las cuales se constituyen también en una parte integral del manejo de los pacientes quirúrgicos severamente enfermos.N/

    Evaluación del proceso de lixiviación por agitación de minerales Au-Ag en la Compañía Minera Ares Castilla - Arequipa

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    Para ta evaluación del presente -estudio se ha trabajado eon un tttinerat que tiene una ley de 6.0 g/TM de Au y 156.0 g/TM de Ag. El oro en este mineral se. encuentra libre y· enespsuJado en cuarzo. y la ptata se presenta en forma de minerales sulfurados (acantita). Por la naturafeza de -esta .mena se ha realizado pruebas de cianuración por agitación a nivel de laboratorio, para ello el mineral ha sido molido a una granulometría de 7 4% -270· mallas. esto con el fin de liberar un buen porcentaje de oro que se encuentra en el cuarzo. De acuerdo a las pruebas preliminares de lixiviación por agitación se ha podido establecer que las variables que tienen mayor influencia en el proceso son: la concentración de NaCN, Pb(N03)2 y el pH; variables· que han servido para realizar las pruebas experimentales utilizando el diseño factorial 2 ^3 • En estas condiciones, el proceso nos ha permitido obtener una extracción de 97.60% de Au y 88.63% de Ag, relativamente superiores a las condiciones actuales de extracción· que es de 96.00% de Au y 87.00% de Ag, finalmente los parámetros obtenidos para mejorar el proceso de extracción fueron: Concentración dé Cianuro de Sodio 0.30%, Concentración de Nitrato de Plomo 190 g/TM y un pH de 10.5.Tesi

    Fine-Grained Access Control with User Revocation in Smart Manufacturing

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    This research has been founded by the European Union’s Horizon 2020 Research and Innovation program under grant agreement No. 871518, a project named COLLABS [19].Collaborative manufacturing is a key enabler of Industry 4.0 that requires secure data sharing among multiple parties. However, intercompany data-sharing raises important privacy and security concerns, particularly given intellectual property and business-sensitive information collected by many devices. In this paper, we propose a solution that combines four technologies to address these challenges: Attribute-Based Encryption for data access control, blockchain for data integrity and non-repudiation, Hardware Security Modules for authenticity, and the Interplanetary File System for data scalability. We also use OpenID for dynamic client identification and propose a new method for user revocation in Attribute-Based Encryption. Our evaluation shows that the solution can scale up to 2,000,000 clients while maintaining all security guarantees.European Union’s Horizon 2020, 87151
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