Biopolymers: Scaffold Applications in Regenerative Medicine

Los biopolímeros se han convertido en un herramienta indispensable para el desarrollo de la medicina regenerativa, su amplio espectro ha permitido la aparición de nuevas técnicas para la generación de andamios de diversos tamaños, formas, con características estructurales únicas capaces de generar e innovar tratamientos nuevos ante enfermedades catastróficas, su aplicación por todas las ramas de investigación como la neurología, endocrinología, en el área cardiovascular, para la reparación de tejidos o donación de órganos ha producido su aplicación como conductores o transportadores de fármacos para lograr una liberación guiada aumentando la efectividad y disminuyendo efectos adversos en el caso de tratamientos contra el cáncer. El objetivo de esta revisión es conocer los fundamentos de la medicina regenerativa, los avances producidos a partir del uso de biopolímeros como una herramienta capaz de desarrollar biomateriales funcionales, tipos, modo de síntesis y aplicabilidad en tratamientos. Esta investigación se realizó a partir de la recopilación de artículos científicos relacionados al área de la salud pública y la aplicación de andamios funcionales como terapia. La funcionalización de andamios radica en la utilización de polímeros biocompatibles capaces de unirse a un sustrato en un ambiente controlado para el desarrollo de una matriz celular, generando la producción de un tejido en específico acorde a las células diana que se han investigado, gracias a esto el posible rechazo ante un injerto producido con las mismas células del paciente permite la aparición de estructuras como vasos sanguíneos u órganos biocompatibles. Este trabajo recapitula la importancia del uso de biopolímeros en la medicina, las técnicas de producción, su estructura, forma y  aplicaciones más importantes para el tratamiento contra enfermedades.Biopolymers have become an indispensable tool for the development of regenerative medicine, their broad spectrum has allowed the emergence of new techniques for the generation of scaffolds of various sizes, shapes, with unique structural characteristics capable of generating and innovating new treatments before catastrophic diseases, its application by all branches of research such as neurology, endocrinology, in the cardiovascular area, for tissue repair or organ donation has produced its application as drug conductors or transporters to achieve a guided release increasing the effectiveness and reducing adverse effects in the case of cancer treatments. The objective of this review is to know the fundamentals of regenerative medicine, the advances produced from the use of biopolymers as a tool capable of developing functional biomaterials, types, synthesis mode and applicability in treatments. This research was carried out from the compilation of scientific articles related to the area of ​​public health and the application of functional scaffolds as therapy. The functionalization of scaffolds lies in the use of biocompatible polymers capable of binding to a substrate in a controlled environment for the development of a cellular matrix, generating the production of a specific tissue according to the target cells that have been investigated, thanks to this the possible rejection of a graft produced with the same cells of the patient allows the appearance of structures such as blood vessels or biocompatible organs. This work recapitulates the importance of the use of biopolymers in medicine, production techniques, their structure, form and most important applications for the treatment against diseases

Blockade of IL-33R/ST2 Signaling Attenuates Toxoplasma gondii Ileitis Depending on IL-22 Expression

Oral T. gondii infection (30 cysts of 76K strain) induces acute lethal ileitis in sensitive C57BL/6 (B6) mice with increased expression of IL-33 and its receptor ST2 in the ileum. Here we show that IL-33 is involved in ileitis, since absence of IL-33R/ST2 attenuated neutrophilic inflammation and Th1 cytokines upon T. gondii infection with enhanced survival. Blockade of ST2 by neutralizing ST2 antibody in B6 mice conferred partial protection, while rmIL-33 aggravated ileitis. Since IL-22 expression further increased in absence of ST2, we blocked IL-22 by neutralizing antibody, which abrogated protection from acute ileitis in ST2 deficient mice. In conclusion, severe lethal ileitis induced by oral T. gondii infection is attenuated by blockade of ST2 signaling and may be mediated in part by endogenous IL-22

Signaling in innate immunity and apicomplexa : role of the adapter protein MyD88 and inflammasome in control of Toxoplasma gondii infection or Cryptosporidium parvum

Les Apicomplexes constituent une vaste famille de parasites protozoaires responsables de nombreuses maladies chez l’Homme et chez les animaux. C’est le cas de Toxoplasma gondii, agent de la toxoplasmose et de Cryptosporidium parvum, responsable de la cryptosporidiose. Ces pathogènes représentent un réel problème de santé publique et vétérinaire. A l’heure actuelle, les seuls moyens de lutte contre ces parasites demeurent la chimiothérapie car il n’existe aucune stratégie prophylactique efficace. L’identification de cibles vaccinales repose sur le décryptage des mécanismes de défense mis en jeux vis-à-vis de ces agents infectieux. Dans le cadre de cette thèse, nos recherches se sont tournées vers l’étude du bras inné de la réponse immunitaire et plus particulièrement vers les voies de signalisation intracellulaires conséquentes de la reconnaissance de ces parasites.No summary availabl

Nanoparticles cellular uptake, trafficking, activation, toxicity and in vitro evaluation

Nanoparticles (NPs) physicochemical properties, such as size, shape, surface chemistry, charge, etc., play a critical role in biological systems interactions, which include NPs' cellular uptake, trafficking, activation, and toxicity. Although nano-bio interactions are multifaceted and complex, their assessment is essential for future therapeutic and diagnostic use since being carriers that deliver specific molecules (i.e., active pharmaceutical ingredients and imaging agents) in intracellular sites. The journey of NPs begins by reaching the plasma membrane and entering the cell mainly through endocytosis. After vesicles pinch off the cell membrane, the intracellular trafficking is mediated by a network of cellular endosomes which direct NPs to the different cellular components. Otherwise, NPs or their contents are released into the cytoplasm. In both cases, NPs can pass undetected or be recognized by the cell leading to a pro or anti-inflammatory response. Indeed, the cell response mostly depends on cell type and NPs physicochemical properties. The principal mechanism by which NPs activate the cell response is RONS production. Other mechanism includes signaling pathways modulation related to metabolic and enzymatic reactions, cell transduction, and immune modulation. Hence, the underlying mechanisms of cellular and subcellular interactions in vitro should be performed to provide insights into NPs' effect. This information helps us to improve their synthesis and design to maximize the clinical benefits while minimizing side effects. Most in vitro tests to evaluate NPs' effect in cells were developed focusing on cell dysfunctions, cytotoxicity, genotoxicity, immunogenicity, and cell death

Determinación de la eficacia de los jabones antibacterianos

Análisis de cuatro variedades de jabones comerciales, sometidos a tres métodos de análisis para realizar una comparación de la eficacia de cada uno de ellos mediante la capacidad de inhibir a las bacterias estudiadas. Entre los métodos empleados, el más importante fue tomado de la Farmacopea Americana obteniendo resultados veráces realizando una categorización mediante la tabla de grado de reactividad en Difución de Agar con la cual podemos dar el grado de reactividad de cada tipo de jabón. En cuanto a los resultados obtenidos se determinó que los jabones antibacterianos tiene un grado poco severo, mientras que el grupo que se destaco fueron los jabones quirúrgicos siendo severos.Doctor en Bioquímica y FarmaciaCuenc

Recent Advances in the Roles of Neutrophils in Toxoplasmosis

International audienceNeutrophils are now recognized as major components of the response to Toxoplasma gondii by their contribution to parasite elimination by a number of mechanisms. This article focuses on recent advances in the understanding of the mechanisms of migration, cytokine release, and formation of extracellular traps by neutrophils during toxoplasmosis

Biological Impact of Exposure to Extremely Fine-Grained Volcanic Ash

At the northwestern edge of South America is located Ecuador. This place is a classical example of an active continental margin with widespread active volcanism. Detailed studies about the impact of volcanic ash on human health are still lacking. Therefore, the disease of exposed populations is unknown. The objective of the present investigation was to assess the biological impact of Pichincha volcanic ash on cell culture and inflammation in murine lung tissues that will contribute to the understanding of the hazards. In this study, the in vivo phase was performed in mice C57BL/6 exposed to several doses of volcanic ash (0.5, 1, and 3.75 mg/100 g mouse body weight). The body weight and survival were controlled during seven days of treatment. The expression of inflammation markers NRLP 3, caspase-1, pro-IL-1, IL-1β, IL-6, IL-8, and h-HPRT was analyzed. The in vitro phase was performed in lung cancer cells A549, peritoneal macrophages, and McCoy cells exposing them to different concentrations of volcanic ash (80, 320, and 1280 μg/cm3) to determine the cytotoxicity and the production of reactive oxygen species. The ash initiated activation of the inflammasome complex NRLP 3 and the initiation of a proinflammatory activity in the murine lung tissue depending on the concentration of this agent. The viability of A549 and McCoy cell decreased with the length of exposure and increased with the concentration of volcanic ash. The activity in superoxide dismutase decreased by about 60%, leading to the formation of reactive oxygen species. These results associated with compounds contained in Pichincha volcanic ash are considered hazardous elements which induce inflammation leading to activate inflammasome NRLP, releasing reactive oxygen species, and producing changes in cell morphology and density, all of which are expression of cytotoxicity