190 research outputs found

    Dynamics of trace metal sorption by an ion-exchange chelating resin described by a mixed intraparticle/film diffusion transport model. The Cd/Chelex case

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    The time-evolution of Cd2+ ion sorption by Chelex 100 resin was studied in batch experiments as a function of time, pH, ionic strength, stirring rate, mass of resin and initial metal ion concentration. In the experimental conditions, the amount of resin sites are in excess with respect to the amount of metal ion, leading to extensive depletion of metal in bulk solution when equilibrium is reached. The data were described using a mixed control mass transport model in finite volume conditions (MCM) that includes explicitly both intraparticle and film diffusion steps. Exact numerical computations and a new approximate analytical expression of this model are reported here. MCM successfully predicts the influence of pH and ionic strength on the experimental Cd(II)/Chelex kinetic profiles (which cannot be justified by a pure film diffusion controlled mechanism) with a minimum number of fitting parameters. The overall diffusion coefficient inside the resin was modelled in terms of the Donnan factor and the resin/cation binding stability constant. The values of the latter coefficient as a function of pH and ionic strength were estimated from the Gibbs-Donnan model. Even though MCM is numerically more involved than models exclusively restricted to film or intraparticle diffusion control, it proves to be accurate in a wider range of values of the mass transfer Biot number and solution/resin metal ratios.The authors gratefully acknowledge support for this research from the Spanish Ministry MINECO (Projects CTM2013-48967 and CTM2016-78798) and by the “Comissionat d'Universitats i Recerca de la Generalitat de Catalunya” (2014SGR1132). FQ acknowledges a grant from AGAUR

    Job´s syndrome and to miliary tuberculosis

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    El síndrome de hiper IgE también denominado síndrome de Job, es una inmunodeficiencia primaria poco frecuente, cuyo modo de herencia puede ser autosómico recesivo o dominante. Se caracteriza por altos niveles de IgE, eosinofilia, abscesos cutáneos, eccema, candidiasis mucocutánea crónica e infecciones pulmonares recidivantes que contribuyen al desarrollo de neumatoceles y bronquiectasias. El germen más frecuentemente aislado es el Staphylococcus aureus. En la actualidad, ante la mayor supervivencia de los pacientes se han comunicado infecciones oportunistas y linfomas. Existen escasas publicaciones de pacientes con enfermedad por Mycobacterium tuberculosis asociada a síndrome de hiper IgE, por lo que consideramos relevante comunicar el caso de un paciente con antecedentes de una tuberculosis pulmonar, que presentó una tuberculosis miliar con grave compromiso respiratorio, con buena respuesta al tratamiento estándar con drogas de primera línea.The hyper Immunoglobulin E syndrome, also known as Job´s syndrome, is a rare primary immunodeficiency, its mechanisms of inheritance maybe recessive or dominant autosomal. It is characterized by high levels of IgE, eosinophilia, skin abscesses, eczema, chronic mucocutaneous candidiasis and recurrent pulmonary infections all of which contribute to the development of pneumatoceles and bronchiectasis. The most frequently isolated bacteria is Staphylococcus aureus. Currently, despite the highest survival of patients, lymphomas and other opportunistic infections have been reported. There are few reports of patients with Mycobacterium tuberculosis infection associated with hyper IgE syndrome. Therefore it is relevant that we report a case history of a patient with pulmonary tuberculosis, presenting miliary tuberculosis and severe respiratory compromise, who responded positively to standard anti-tuberculous treatment with first line drugs.Fil: Gamberale, Ana. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas ; ArgentinaFil: Moreira, Ileana. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños ; ArgentinaFil: Bartoletti, Bruno. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas ; ArgentinaFil: Cruz, Víctor. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas ; ArgentinaFil: Bezrodnik, Liliana. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alberti, Federico. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas ; ArgentinaFil: Castro Zorrilla, Liliana. Universidad de Buenos Aires; ArgentinaFil: Palmero, Domingo. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas ; Argentin

    53 a neuro specific gene therapy approach to treat cognitive impairment in down syndrome by rna interference

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    Down syndrome (DS) is a genetic disorder caused by the presence of a third copy of chromosome 21. DS affects multiple organs, resulting in characteristic facial features, muscular hypotonia, heart defects, brain development impairment, and varying degrees of intellectual disability. Trisomic mouse models of DS reproduce the main cognitive disabilities of the human syndrome. In particular, DS mice show structural and functional synaptic impairment as well as learning and memory deficits, largely determined by altered GABAergic transmission through chloride-permeable GABAa receptors (GABAaR). In particular, we have recently found that intracellular chloride accumulation shifts GABAAR-mediated signaling from inhibitory to excitatory in the adult brain of the Ts65Dn mouse model of DS. Accordingly, intracellular chloride accumulation was paralleled by increased expression of the chloride importer NKCC1 (Na-K-Cl cotransporter) in the brains of both trisomic mice and DS patients.Our findings on NKCC1 as a pivotal molecular target for the rescue of cognitive deficits in DS opens the possibility of a gene therapy approach to treat the disease. Here, to normalize NKCC1 expression and rescue synaptic dysfunctions as well as cognitive deficits in Ts65Dn mice we have developed and characterized a knock-down approach to normalize NKCC1 activity. Reducing the expression of the chloride importer NKCC1 by RNA interference restored GABAAR-mediated inhibition and also rescued the structural dendritic deficits found in trisomic neurons in vitro. Most importantly, focal administration of an AAV expressing a silencing RNA under the transcriptional control of a neuron-specific promoter in the hippocampus of Ts65Dn animals mediated NKCC1 knockdown in vivo and rescued behavioral performance on different learning and memory tests at levels undistinguishable from those of WT mice.Our findings demonstrate that NKCC1 overexpression drives excitatory GABAAR signaling in trisomic cells, leading to structural neuronal abnormalities and behavioral impairments in DS mice. Moreover, our study identifies a new gene therapy target for treatments aimed at rescuing cognitive disabilities in individuals with DS

    Bioimpedance Vector References Need to Be Period‐ Specific for Assessing Body Composition and Cellular Health in Elite Soccer Players: A Brief Report

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    none9noPurpose: Bioimpedance data through bioimpedance vector analysis (BIVA) is used to evaluate cellular function and body fluid content. This study aimed to (i) identify whether BIVA patters differ according to the competitive period and (ii) provide specific references for assessing bioelectric properties at the start of the season in male elite soccer players. Methods: The study included 131 male soccer players (age: 25.1 ± 4.7 yr, height: 183.4 ± 6.1 cm, weight: 79.3 ± 6.6) registered in the first Italian soccer division (Serie A). Bioimpedance analysis was performed just before the start of the competitive season and BIVA was applied. In order to verify the need for period-specific references, bioelectrical values measured at the start of the season were compared to the reference values for the male elite soccer player population. Results: The results of the two-sample Hotelling T2tests showed that in the bivariate interpretation of the raw bioimpedance parameters (resistance (R) and reactance (Xc)) the bioelectric properties significantly (T2= 15.3, F = 7.6, p ≤ 0.001, Mahalanobis D = 0.45) differ between the two phases of the competition analyzed. In particular, the mean impedance vector is more displaced to the left into the R-Xc graph at the beginning of the season than in the first half of the championship. Conclusions: For an accurate evaluation of body composition and cellular health, the tolerance ellipses displayed by BIVA approach into the R-Xc graph must be period-specific. This study provides new specific tolerance ellipses (R/H: 246 ± 32.1, Xc/H: 34.3 ± 5.1, r: 0.7) for performing BIVA at the beginning of the competitive season in male elite soccer players.openBongiovanni T.; Mascherini G.; Genovesi F.; Pasta G.; Iaia F.M.; Trecroci A.; Ventimiglia M.; Alberti G.; Campa F.Bongiovanni T.; Mascherini G.; Genovesi F.; Pasta G.; Iaia F.M.; Trecroci A.; Ventimiglia M.; Alberti G.; Campa F

    Enhancement of TiO2 NPs Activity by Fe3O4 Nano-Seeds for Removal of Organic Pollutants in Water

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    The enhancement of the photocatalytic activity of TiO2 nanoparticles (NPs), synthesized in the presence of a very small amount of magnetite (Fe3O4) nanoparticles, is here presented and discussed. From X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analyses, the crystallinity of TiO2 nanoparticles (NPs) seems to be affected by Fe3O4, acting as nano-seeds to improve the tetragonal TiO2 anatase structure with respect to the amorphous one. Photocatalytic activity data, i.e., the degradation of methylene blue and the Ofloxacin fluoroquinolone emerging pollutant, give evidence that the increased crystalline structure of the NPs, even if correlated to a reduced surface to mass ratio (with respect to commercial TiO2 NPs), enhances the performance of this type of catalyst. The achievement of a relatively well-defined crystal structure at low temperatures (Tmax = 150 \u25e6C), preventing the sintering of the TiO2 NPs and, thus, preserving the high density of active sites, seems to be the keystone to understand the obtained results

    Nutrient and herbivore alterations cause uncoupled changes in producer diversity, biomass and ecosystem function, but not in overall multifunctionality

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    Altered nutrient cycles and consumer populations are among the top anthropogenic influences on ecosystems. However, studies on the simultaneous impacts of human-driven environmental alterations on ecosystem functions, and the overall change in system multifunctionality are scarce. We used estuarine tidal flats to study the effects of changes in herbivore density and nutrient availability on benthic microalgae (diversity, abundance and biomass) and ecosystem functions (N2-fixation, denitrification, extracellular polymeric substances -EPS- as a proxy for sediment cohesiveness, sediment water content as a proxy of water retention capacity and sediment organic matter). We found consistent strong impacts of modified herbivory and weak effects of increased nutrient availability on the abundance, biomass and diversity of benthic microalgae. However, the effects on specific ecosystem functions were disparate. Some functions were independently affected by nutrient addition (N2-fixation), modified herbivory (sediment organic matter and water content), or their interaction (denitrification), while others were not affected (EPS). Overall system multifunction remained invariant despite changes in specific functions. This study reveals that anthropogenic pressures can induce decoupled effects between community structure and specific ecosystem functions. Our results highlight the need to address several ecosystem functions simultaneously for better ecosystem characterization and management.Instituto de Limnología "Dr. Raul A. Ringuelet

    Nutritional interventions for reducing the signs and symptoms of exercise-induced muscle damage and accelerate recovery in athletes: current knowledge, practical application and future perspectives

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    Purpose This review provides an overview of the current knowledge of the nutritional strategies to treat the signs and symptoms related to EIMD. These strategies have been organized into the following sections based upon the quality and quantity of the scientific support available: (1) interventions with a good level of evidence; (2) interventions with some evidence and require more research; and (3) potential nutritional interventions with little to-no-evidence to support efficacy. Method Pubmed, EMBASE, Scopus and Web of Science were used. The search terms ‘EIMD’ and ‘exercise-induced muscle damage’ were individually concatenated with ‘supplementation’, ‘athletes’, ‘recovery’, ‘adaptation’, ‘nutritional strategies’, hormesis’. Result Supplementation with tart cherries, beetroot, pomegranate, creatine monohydrate and vitamin D appear to provide a prophylactic effect in reducing EIMD. β-hydroxy β-methylbutyrate, and the ingestion of protein, BCAA and milk could represent promising strategies to manage EIMD. Other nutritional interventions were identified but offered limited effect in the treatment of EIMD; however, inconsistencies in the dose and frequency of interventions might account for the lack of consensus regarding their efficacy. Conclusion There are clearly varying levels of evidence and practitioners should be mindful to refer to this evidence-base when prescribing to clients and athletes. One concern is the potential for these interventions to interfere with the exercise-recovery-adaptation continuum. Whilst there is no evidence that these interventions will blunt adaptation, it seems pragmatic to use a periodised approach to administering these strategies until data are in place to provide and evidence base on any interference effect on adaptation

    Efecto del raleo en la densidad básica de la madera de Eucalyptus grandis

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    La madera es un material particularmente heterogéneo y de carácter anisótropo, sus propiedades físicas, mecánicas y químicas varían notablemente entre especies, entre árboles de una misma especie y entre diferentes partes dentro de un árbol. La silvicultura puede hasta cierto punto modificar, controlar, minimizar o mejorar las propiedades y características de cada material genético. Con el objetivo de evaluar el efecto del raleo en la densidad básica de la madera (DB) y su variación a lo largo del fuste, se evaluaron 36 árboles de 16,2 años de edad provenientes de un ensayo de raleo en suelo mestizo del departamento Colon, Entre Ríos. El ensayo se constituye de 4 intensidades de raleo (IR) con densidades finales de 827, 615, 414 y 291 árboles/ha. Mediante muestreo destructivo se obtuvieron discos a lo largo del fuste y, en el presente trabajo se analizó la DB en tres posiciones de altura P1 (4,20 m), P2 (8,40 m) y P3 (12,50 m). De cada disco se extrajeron probetas en cuartones según la orientación norte y sur de las que se obtuvo la DB (DBN y DBS); a partir de éstas, se calculó la DB promedio (DBprom). Los datos fueron analizados con el procedimiento GLM utilizando el software SAS. Los principales resultados mostraron: diferencias altamente significativas entre las IR (p<0,0001) en DBN, DBS y DBprom, presentando mayor valor de densidad básica el tratamiento de raleo que finaliza con 291 árb/ha. También se diferenció significativamente la DB entre las posiciones de altura, mostrando un aumento en la DB con la altura en el fuste, en tanto que la interacción IR x P no presentó significancia estadística.EEA Bella VistaFil: Caniza, Federico Javier. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bella Vista; ArgentinaFil: Mastrandrea, Ciro Andres. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Concordia; ArgentinaFil: Alberti, Sebastián. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Concordia; ArgentinaFil: Aparicio, Jorge Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bella Vista; ArgentinaFil: Ingaramo, Luciana And. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Concordia; Argentin

    Versatilidad del clavo endomedular retrógrado largo de tibia para artrodesis tibio-talo-calcánea en pacientes con lesiones asociadas en el mismo segmento

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    Introducción: La afección articular que lleva a la necesidad de una artrodesis tibio-calcánea puede estar acompañada de una segunda lesión en el mismo segmento óseo, y los clavos de diseño para artrodesis no tienen la longitud adecuada para cubrir ambas lesiones. No hallamos opciones terapéuticas para este tipo de lesiones en la bibliografía. Objetivo: Presentar una serie de casos en los que se utilizó un único clavo de tibia (de colocación anterógrada) de forma retrógrada, con el doble objetivo de efectuar una artrodesis tibio-talo-calcánea, sumada al tratamiento de una lesión asociada en un mismo tiempo quirúrgico. Materiales y Métodos: Se evaluó, en forma retrospectiva, desde septiembre de 2009 hasta junio de 2019, a un grupo de 12 pacientes que requirió una artrodesis tibio-talo-calcánea sumada a la necesidad de resolver simultáneamente un defecto secundario local. La edad promedio fue de 43.7 años, y el seguimiento global fue de 43.9 meses. Resultados: Todos los pacientes lograron una artrodesis tibio-calcánea constatada en radiografías de frente y de perfil, y el 83,3% recuperó el stock óseo de manera completa. Conclusión: Ante la ausencia en el mercado de osteosíntesis para resolver las patologías asociadas en un mismo paciente, proponemos el uso del clavo endomedular largo de tibia colocado de manera retrógrada como una opción de tratamiento, porque se ha demostrado que es eficaz para lograr la artrodesis tibio-calcánea. Además, se lo pudo utilizar como guía en el alargamiento y el transporte óseo, y como estabilización para tratar lesiones simultáneas

    Preparation of sesquiterpene lactone derivatives: Cytotoxic activity and selectivity of action

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    Cancer is one of the most important causes of death worldwide. Solid tumors represent the great majority of cancers (>90%) and the chemotherapeutic agents used for their treatment are still characterized by variable efficacy and toxicity. Sesquiterpene lactones are a group of naturally occurring compounds that have displayed a diverse range of biological activities including cytotoxic activity. A series of oxygenated and oxy-nitrogenated derivatives (4–15) from the sesquiterpene lactones cumanin (1), helenalin (2), and hymenin (3) were synthesized. The silylated derivatives of helenalin, compounds 13 and 14, were found to be the most active against tumor cell lines, with GI50 values ranging from 0.15 to 0.59 µM. The ditriazolyl cumanin derivative (11) proved to be more active and selective than cumanin in the tested breast, cervix, lung, and colon tumor cell lines. This compound was the least toxic against splenocytes (CC50 = 524.1 µM) and exhibited the greatest selectivity on tumor cell lines. This compound showed a GI50 of 2.3 µM and a SI of 227.9 on WiDr human colon tumor cell lines. Thus, compound 11 can be considered for further studies and is a candidate for the development of new antitumor agents.Fil: Beer, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Bivona, Augusto Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Sanchez Alberti, Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni; ArgentinaFil: Cerny, Natacha. Universidad Nacional de Luján. Instituto de Ecología y Desarrollo Sustentable. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ecología y Desarrollo Sustentable; ArgentinaFil: Reta, Guillermo Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Martín, Víctor S.. Universidad de La Laguna; EspañaFil: Padrón, José M.. Universidad de La Laguna; EspañaFil: Malchiodi, Emilio Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Sülsen, Valeria Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Donadel, Osvaldo Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; Argentin
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