Search results for "biomaterial"

Evaluación de Biopolímeros como Superficie de Regeneración de Tejidos Dérmico y Cardíaco

2018

Las enfermedades cardiovasculares son la primera causa de muerte y de hospitalización en los países desarrollados. La cardiopatía isquémica se produce como consecuencia de un flujo coronario deficiente, con el consiguiente déficit en el aporte de oxígeno para cubrir las necesidades metabólicas del miocardio. Las modalidades terapéuticas actuales para el tratamiento del infarto agudo de miocardio son limitadas y van desde el tratamiento médico en la fase aguda hasta la aplicación de dispositivos de asistencia mecánica al ventrículo izquierdo y el trasplante de corazón. Todo ello ha hecho que en los últimos años se hayan desarrollado nuevas técnicas para encontrar solución a las cardiopatías …

Síntesis y caracterización de scaffolds poliméricos para la ingeniería de tejidos

2013

El desarrollo del campo de la ingeniería de tejidos surge ante la necesidad de dar solución a las deficiencias asociadas a la sustitución de tejidos cuando se han producido pérdidas irreparables de los mismos o no funcionan correctamente. Muchos tipos de células necesitan scaffolds para guiar el desarrollo de nuevos tejidos con la función apropiada, servir como sustrato para la adhesión celular y al mismo tiempo proporcionar un soporte mecánico para el nuevo tejido que ha crecido. El objetivo principal de este trabajo ha sido desarrollar métodos de síntesis de scaffolds poliméricos, basados en el método convencional denominado colado de sólidos en combinación con el lixiviado de partículas,…

Legal controversies and ethical considerations concerning the property rights in the human body

2021

When considering the rise of the biotech industry over the years, one might wonder if the procurement of the biological materials, that are necessary for the success of the industry, was done through ethical and safe measures, especially considering the stagnant position of many countries towards granting individuals ownership rights over their bodies. As such, this paper inspects and compares the current legal approaches that are used in certain common law and civil law jurisdictions to determine individuals’ rights over their bodies, and considers the bundle of rights concept and the law of equity as possible solutions to the ethical and equitable deficiencies observed in certain jurisdic…

V2O5 nanowires with an intrinsic peroxidase-like activity

2010

V2O5 nanowires exhibit an intrinsic catalytic activity towards classical peroxidase substrates such as 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 3,3,5,5,-tetramethylbenzdine (TMB) in the presence of H2O2. These V2O5 nanowires show an optimum reactivity at a pH of 4.0 and the catalytic activity is dependent on the concentration. The Michaelis-Menten kinetics of the ABTS oxidation over these nanowires reveals a behavior similar to that of their natural vanadium-dependent haloperoxidase (V-HPO) counterparts. The V2O5 nanowires mediate the oxidation of ABTS in the presence of H2O2 with a turnover frequency (k(cat)) of 2.5 x 10(3) s(-1). The K-M values of the V2O5 nanowire…

Human ABCB1 confers cells resistance to cytotoxic guanidine alkaloids from Pterogyne nitens.

2015

Multidrug resistance (MDR) caused by human ABCB1 (P-glycoprotein/MDR1) is one of the major obstacles in chemotherapy. To understand the mechanism of MDR by ABCB1 and circumvent the MDR, in the present study, we established human ABCB1-expressing cells (Flp-In-293/ABCB1 cells) and examined the cytotoxic effects of four guanidine alkaloids from Pterogyne nitens (galegine, nitensidine A, pterogynidine and pterogynine) using Flp-In-293/Mock and Flp-In-293/ABCB1 cells. The activity of ABCB1 in Flp-In-293/ABCB1 cells were confirmed by typical substrates for ABCB1 (taxol and vinblastine) in MTT assay. Flp-In-293/ABCB1 cells were also resistant to the four guanidine alkaloids as well as taxol and v…

Combined metabolic activity within an atrazine-mineralizing community enriched from agrochemical factory soil

2007

Abstract The main objective of this work was to characterize an atrazine-mineralizing community originating from agrochemical factory soil, especially to elucidate the catabolic pathway and individual metabolic and genetic potentials of culturable members. A stable four-member bacterial community, characterized by colony morphology and 16S rDNA sequencing, was rapidly able to mineralize atrazine to CO 2 and NH 3 . Two primary organisms were identified as Arthrobacter species (ATZ1 and ATZ2) and two secondary organisms (CA1 and CA2) belonged to the genera Ochrobactrum and Pseudomonas, respectively. PCR assessment of atrazine-degrading genetic potential of the community, revealed the presence…

Experimental and robust modeling approach for lead(II) uptake by alginate gel beads: influence of the ionic strength and medium composition.

2014

Abstract Systematic kinetic and equilibrium studies on the lead ions removal ability by Ca-alginate gel beads have been performed by varying several internal parameters, namely, number of gel beads, nature and composition of the ionic medium and pH, which allowed us to model a wastewater in order to closely reproduce the composition of a real sample. Moreover, the effects brought about the different ionic species present in the reacting medium have been evaluated. Differential Pulse Anodic Stripping Voltammetry (DP-ASV), has been systematically used to perform kinetic and equilibrium measurements over continuous time in a wide range of concentration. Kinetic and equilibrium data have been q…

Characterization of particle morphology of biochanin A molecularly imprinted polymers and their properties as a potential sorbent for solid-phase ext…

2014

Abstract Molecularly imprinted polymers (MIPs) with biochanin A as a template were obtained using a bulk polymerization with non-covalent imprinting approach. The polymers were prepared in acetonitrile as porogen, using ethylene glycol dimethacrylate (EDMA) as cross-linking agent. The synthesis, with an application of 1′,1′-azobis(cyclohexanecarbonitrile) (ACHN) as an initiator, has been performed thermally. During the synthesis process the effect of different functional monomers such as methacrylic acid (MAA), acrylamide (AA) and 4-vinylpyridine (4-VP) was investigated. The application of nitrogen sorption porosimetry, scanning electron microscopy (SEM), and Fourier transform infrared spec…

PROGETTAZIONE, SINTESI E CARATTERIZZAZIONE DI NUOVI DERIVATI POLISACCARIDICI E POLIURETANICI PER LA PRODUZIONE DI BIOMATERIALI INNOVATIVI PROCESSABIL…

2022

Double Thermoresponsive Block Copolymers Featuring a Biotin End Group

2010

A poly(oligo(ethylene glycol) monomethyl ether methacrylate)-block-poly(N-isopropyl methacrylamide) (POEGMA-b-PNIPMAM) block copolymer with a biotin end group on the PNIPMAM block as a biotarget was synthesized as a model system for temperature-controlled polymer immobilization. The synthesis was based on RAFT polymerization followed by postpolymerization modification of an activated ester precursor block and an exchange of the dithioester end group within one step. NMR, differential scanning calorimetry (DSC), dynamic light scattering (DLS), and turbidimetry measurements were performed to investigate the stimulus-responsive properties. The double thermoresponsive POEGMA-b-PNIPMAM with biot…