Examinando por Materia "VIRUS"

Mostrando1 - 6 de 6
  • Artículo de Publicación Periódica
    Electrostatic interactions in virus removal by ultrafiltration membranes
    (2018-02) Gentile, Guillermina José; Cruz, Mercedes Cecilia; Rajal, Verónica Beatriz; Fidalgo de Cortalezzi, María Marta
    "Ultrafiltration membranes are increasingly used in potabilization to remove viral particles. This removal is controlled by electrostatic repulsion, attachment and size exclusion. The effect of electrostatic interaction in virus filtration was investigated. Our work included characterization of bacteriophage PP7 and polyethersulfone membrane with respect to size and surface charge; the removal of this bacteriophage at laboratory scale by ultrafiltration membrane process and the mechanism and limitations were analyzed and discussed under DLVO and XDLVO theories. A partial removal of the bacteriophage was achieved; however, enhanced separation may be achieved considering that the process is affected by the aqueous matrix. The presence of divalent cations diminished the effectiveness of the procedure as opposed to monovalent cations and species with amphoteric behavior such as bicarbonate. DLVO and XDLVO predicted the interactions studied between bacteriophage PP7 and polyethersulfone membrane."
  • Artículo de Publicación Periódica
    Imidazo[2,1-b]thiazole carbohydrate derivatives: synthesis and antiviral activity against Junin virus, agent of Argentine hemorrhagic fever
    (2011-01) Barradas, José Sebastián; Errea, María Inés; D´Accorso, Norma B.; Sepúlveda, Claudia Soledad; Damonte, Elsa Beatriz
    "Herein, we describe the syntheses of 3,5-disubstituted imidazo[2,1-b]thiazole. The cyclization step was performed in two different conditions by using either thermal or microwave heating. Comparing the results of both methodologies, we found that the microwave assistance is an improved alternative to obtain this family of heterocyclic compound. Compounds were first evaluated for cytotoxicity in Vero cells by MTT method and then, the antiviral activity was assayed by a virus yield inhibition assay in the range of concentrations lower than the corresponding CC50, using JUNV strain IV4454 as the model system. The most active compounds (3 and 4), showed a level of antiviral activity against JUNV in monkey Vero cells better than the reference substance ribavirin. Then, they are promising lead compound for further analysis and characterization to establish their therapeutic potential against hemorrhagic fever viruses."
  • Proyecto final de Grado
    Impacto del genotipo TLR4 en la respuesta humoral contra el virus sincicial respiratorio
    (2018) Levy, Hernán; Acosta, Patricio Leandro
    "El objetivo del presente trabajo consiste en "caracterizar la respuesta inmune humoral frente al virus del VSR de una muestra poblacional con diferentes genotipos en el gen codificante para TLR4 para determinar el papel del genotipo en la respuesta."
  • Artículo de Publicación Periódica
    Interparticle effects in the cotransport of viruses and engineered nanoparticles in saturated porous media
    (2021-10) Gentile, Guillermina José; Blanco Fernández, María Dolores; Fidalgo de Cortalezzi, María Marta
    "The effects of P25 TiO2 nanoparticles on the transport in saturated porous media of the bacteriophage PP7 was investigated. Two levels of ionic strength were considered, given by monovalent and divalent cations, Na+ and Ca2+. The viruses and the P25 particles were characterized with respect to size and surface charge, by dynamic light scattering and electron microscopy. The breakthrough curves were obtained for suspensions of each particle and both combined, using UV absorbance to quantify P25 and RT-qPCR for PP7. In the single transport experiments, P25 was retained, while the viruses mostly eluted the sand bed. However, in the cotransport experiments, retention increased for the virus and decreased for the TiO2 nanoparticles under high viral content, due to heteroaggregation among the colloids in the incoming suspension, electrostatic interactions, and ripening. The interparticle interactions were modeled by DLVO theory, resulting in agreement with the experimental observations, which highlights the electrostatic nature."
  • Tesis de doctorado
    Surface phenomena affecting the transport and removal of viruses and bacteria in natural and engineered porous media: implications for water quality
    (2016-06) Gentile, Guillermina José; Fidalgo de Cortalezzi, María Marta; Errea, María Inés
    "El objetivo general de la tesis fue profundizar el conocimiento de las interacciones presentes en las interfases entre superficies, microorganismos y nanomateriales en medios acuosos. En particular se estudiaron las interacciones en tres sistemas diferentes: transporte de microorganismos y nanopartículas a través de lechos porosos, eliminación en sistemas acuosos de bacteriófagos modelo por medio de membranas cerámicas nanoestructuradas, y membranas empleadas en ultrafiltración de aguas para la remoción de bacteriófagos como modelo de virus patógenos. Los resultados obtenidos podrán ser de utilidad para elaborar mejoras en los procesos estudiados con fines de asegurar la calidad del agua. Adicionalmente, se analizó la factibilidad de la aplicación de membranas en el proceso de ósmosis retardada por presión (PRO) para generación de energía eléctrica en el país."
  • Artículo de Publicación Periódica
    Virus removal by iron oxide ceramic membranes
    (2014-09) Fidalgo de Cortalezzi, María Marta; Gallardo, María V.; Yrazu, Fernando M.; Gentile, Guillermina José; Opezzo, Oscar; Pizarro, Ramón A.; Poma, Hugo R.; Rajal, Verónica Beatriz
    "Nanoporous iron oxide ceramics were studied for the removal of virus contamination from water. Supported and unsupported iron oxide nanostructured hematite was fabricated by a green chemistry route from ferroxane nanoparticles. The material had a surface area of approximately 30 m2/g and a mean pore size of 65 nm. Bacteriophage P22 was chosen as a model for human virus. The kinetics and equilibrium of the attachment process was investigated. P22 adsorption isotherms on iron oxide were described by the Freundlich equation. Batch experiments resulted in 1.5 LRVs. Removal proceeded rapidly for the first 7 h; next, a diffusion-limited stage occurred. Dynamic attachment experiments demanded extensive recirculation to achieve significant reduction levels. Up to 3 LRV were observed. The enhanced performance can be explained by the higher iron oxide area available and the facilitated access to inner porosity sites that were previously unavailable due to slow diffusion. The role of electrostatic interactions in the attachment mechanisms was confirmed by the dependence of the isotherm on the ionic strength of the suspension medium. P22 bacteriophage is expected to attach to the iron oxide by electrostatic forces up to a pH of 6.5. DLVO theory predicts moderately well the interaction energies between P22 particles themselves and between the phage and the ceramic. However, a slight underestimation of the P22–P22 repulsive forces was evident by comparison to the experimental data."