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Search Results: 1 - 10 of 166 matches for " Anahí Magdaleno "
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Evaluation of the Anti-Trypanosoma Cruzi Effects of the Antipsychotic Drug Levomepromazine  [PDF]
Inga Eva Stik Lange, Elisabeth Mieko Furusho Pral, Anahí Magdaleno, Ariel Mariano Silber
International Journal of Clinical Medicine (IJCM) , 2012, DOI: 10.4236/ijcm.2012.35067
Abstract: Chagas disease, caused by the protozoan Trypanosoma cruzi, is a relevant parasitic disease in the Americas. Current chemotherapy relies on Nifurtimox and Benznidazole, which present serious drawbacks, including high toxicity, low efficiency and the emergence of resistant strains. In the present work, the perspectives of levomepromazine, a tri-cyclic compound belonging to the family of phenotiazines with well-known properties as antipsychotics were evaluated as a potential anti-T. cruzi drug. We show that this drug is able to inhibit the proliferation of epimastigotes (IC50 = 0.41 ± 0.01 mM) and to interfere with the infection of the host cells (IC50 = 0.34 ± 0.01 mM). Interestingly, the treatment with levomepromazine affected the ability of metabolites such as glucose, proline and glutamate to fuel the recovery of epi-mastigotes after being submitted to metabolic stress. These findings prompt levomepromazine as a promising leader drug to obtain new trypanocidal activities.
Genotoxicidad y determinación de compuestos tóxicos en un residuo líquido hospitalario de Buenos Aires, Argentina
PAZ, Marta;MAGDALENO, Anahí;TORNELLO, Carina;BALBIS, Natalia;MORETTON, Juan;
Revista internacional de contaminación ambiental , 2008,
Abstract: abstract raw wastewaters from health centers transport a great variety of chemical compounds like medical drugs, disinfectants, detergent, laboratory reagents, etc. the complex and fluctuant chemical composition of these effluents opens the possibility of an environmental toxicity scenario. even considering that these wastewaters are diluted after their discharge towards the municipal sewer system, certain substances present in the effluents can generate by cumulative effect a biological imbalance in aquatic ecosystems. in buenos aires city, the urban sewer waters are delivered into the río de la plata with no previous depuration treatment, being the latter the main source of drinking water for the city. the objective of this work is to analyze the toxicity and genotoxicity in wastewater samples of san martin hospital, an important medical center that daily releases 565 m3 of wastewaters to the sewer system. the evaluation of the genotoxic potential of hospital effluents was performed with different biological systems: the ames test, the saccharomyces cereviciae d7 test and the rec (+/-) assay with bacillus subtilis. samples of raw wastewater and the correspondent xad4 extract were submitted to biological test. no mutagenic effect, either with the ames test or the rec (+/-), was detected. only those samples taken on friday induced gene conversion in saccharomyces cereviciae d7. simultaneously, the chemical toxicity profile of the samples was studied. cadmium, chromium, mercury and organic halogenated compounds concentrations were in all cases below the toxicity limits established for effluents release to the sewer system. the results obtained confirm the existence of unidentified hazardous substances in hospital wastewater. the determination of toxicants or toxic substances concentration in the samples, in addition to a test battery for genotoxicity detection studies, provide more meaningful information to decision-makers in the estimation of environmental risk of h
Evaluación ecotóxica y genotóxica de aguas residuales hospitalarias Ecotoxicological and genotoxic evaluation of hospital wastewaters
Anahí Magdaleno,ángela B Juárez,Marta Paz,Carina Tornello
Acta Toxicológica Argentina , 2012,
Abstract: Los líquidos residuales provenientes de hospitales constituyen un riesgo potencial para los ecosistemas y la salud humana debido a la presencia de compuestos tóxicos y genotóxicos. El objetivo de este trabajo fue analizar la toxicidad y la genotoxicidad de los efluentes provenientes del Hospital de Clínicas José de San Martín (Buenos Aires). Las muestras del efluente se tomaron durante los días y horarios de mayor actividad del hospital y se separaron en dos fracciones: acuosa y orgánica (extractos). Los ensayos de toxicidad se realizaron en la fracción acuosa utilizando dos especies de algas verdes: Pseudokirchneriella subcapitata y Chlorella vulgaris. La genotoxicidad se evaluó en las dos fracciones mediante el ensayo de Salmonella/ microsomas en ausencia y presencia de mezcla S9, utilizando las cepas TA98 y TA100. Veintinueve muestras de un total de 53 muestras analizadas resultaron tóxicas para P. subcapitata (entre 18 y 55 % de inhibición), mientras que sólo 8 muestras lo fueron para C. vulgaris (entre 21 y 50 % de inhibición). Ninguna de las muestras resultó genotóxica para Salmonella, ni en los extractos ni en las fracciones acuosas. De los tres ensayos utilizados, P. subcapitata fue el más sensible, siendo el ensayo más apropiado para el monitoreo de estos efluentes. Wastewaters from hospitals constitute a potential risk to the ecosystems and human health due to the presence of toxic and genotoxic chemical compounds. The objective of this work was to analyze the toxicity and genotoxicity of wastewaters from the "Hospital de Clínicas José de San Martín" (Buenos Aires). Wastewater samples were obtained during the days and hours of major hospital activities and they were separated into two fractions: aqueous and organic (extracts). The toxicity assays were performed for the aqueous fraction using the green algae species: Pseudokirchneriella subcapitata and Chlorella vulgaris. Genotoxicity was assessed for the two fraction samples using the Salmonella/microsome assay in presence and in absence of S9 mix, with the strains TA98 and TA100. Twenty nine of the 53 total analyzed samples were toxic to P. subcapitata (between 18 and 55 % inhibition), whereas only 8 samples were toxic to C. vulgaris (between 21 and 50 % inhibition). None of the samples resulted genotoxic to Salmonella. Of the three tests used, P. subcapitata was the most sensible, resulting in the most suitable species to be used in hospital wastewaters monitoring.
Genotoxicidad y determinación de compuestos tóxicos en un residuo líquido hospitalario de Buenos Aires, Argentina
Marta Paz,Anahí Magdaleno,Carina Tornello,Natalia Balbis
Revista internacional de contaminación ambiental , 2008,
Abstract: Los líquidos residuales no tratados provenientes de centros de salud presentan un riesgo potencial para la salud y el ambiente debido a que transportan sustancias químicas con efectos tóxicos y genotóxicos. La composición de estos líquidos residuales fluctúa continuamente debido a la gran diversidad de medicamentos, desinfectantes, solventes, reactivos de laboratorio, detergentes y otros compuestos vertidos a los mismos. En la Ciudad de Buenos Aires, las aguas residuales procedentes de los centros hospitalarios no son tratadas in situ, sino que se transportan a través del sistema cloacal y se vierten con un mínimo tratamiento al Río de La Plata, principal fuente de abastecimiento de agua potable para una población de 10 millones de habitantes. El objetivo de este trabajo es analizar la presencia de compuestos tóxicos y la genotoxicidad en aguas residuales del Hospital de Clínicas San Martín de la Universidad de Buenos Aires, centro médico de alta complejidad que vuelca diariamente 565 m3 de agua residual al colector cloacal. Se tomaron muestras de este líquido de lunes a viernes, que se ensayaron como agua cruda filtrada y como extracto obtenido por pasaje a través de resinas XAD4. La determinación de toxicidad y genotoxicidad del efluente hospitalario se realizó utilizando distintos sistemas biológicos normatizados: los ensayos de Ames, Saccharomyces cereviciae D7 y Rec (+/-) con Bacillus subtilis. En ninguno de estos ensayos se evidenció efecto tóxico sobre las cepas empleadas. Los datos obtenidos con los ensayos de Ames y Rec (+/-) no permitieron demostrar actividad mutagénica ni en las muestras de agua cruda ni en los extractos XAD4. Las determinaciones realizadas con Saccharomyces cereviciae D7 mostraron actividad genotóxica en el agua residual del día viernes. Se determinó, además, el perfil de tóxicos presentes en las muestras al seleccionar los más probables, como cadmio, cromo, mercurio y compuestos orgánicos halogenados; en todos los casos, las concentraciones de estos compuestos en las aguas residuales fueron inferiores a los límites establecidos para los vertidos industriales a colectores cloacales. El efecto genotóxico no pudo ser relacionado con la presencia de estos contaminantes, lo que demuestra la importancia de utilizar ensayos químicos y biológicos para determinar el posible riesgo ambiental de estos vertidos.
The Involvement of Glutamate Metabolism in the Resistance to Thermal, Nutritional, and Oxidative Stress in Trypanosoma cruzi
Anahí Magdaleno,Brian Suárez Mantilla,Sandra C. Rocha,Elizabeth M. F. Pral,Ariel M. Silber
Enzyme Research , 2011, DOI: 10.4061/2011/486928
Abstract: The inhibition of some glutamate metabolic pathways could lead to diminished parasite survival. In this study, the effects of L-methionine sulfoximine (MS), DL-methionine sulfone (MSO), and DL-methionine sulfoxide (MSE), three glutamate analogs, on several biological processes were evaluated. We found that these analogs inhibited the growth of epimastigotes cells and showed a synergistic effect with stress conditions such as temperature, nutritional starvation, and oxidative stress. The specific activity for the reductive amination of α-ketoglutaric acid, catalyzed by the NADP+-linked glutamate dehydrogenase, showed an increase in the NADP+ levels, when MS, MSE, and MSO were added. It suggests an eventual conversion of the compounds tested by the T. cruzi cells. The fact that trypomastigote bursting was not significantly inhibited when infected cells were treated with these compounds, remarks the existence of relevant metabolic differences among the different life-cycle stages. It must be considered when proposing a new therapeutic drug. 1. Introduction Chagas’ disease, also known as American trypanosomiasis, is a parasitic illness caused by the hemoflagellate Trypanosoma cruzi, which is transmitted to humans by blood-sucking triatomine vectors. The parasite is prevalent in South and Central America and infects 12–15 million people in the region, with approximately 40,000 new cases per year, and approximately 12,500 deaths per year due to cardiac disease (WHO, http://www.who.int/tdr/). In addition, more than 100,000 chronically infected individuals currently reside in the United States, Canada, and Europe due to migration from endemic countries [1]. At present, no clinically approved drug exists for the satisfactory treatment of chronic stage of the infection. Benznidazole and nifurtimox are the only available drugs prescribed for T. cruzi and are 60–80% effective in the treatment of acute infection, but the use of these drugs to treat the chronic phase remains controversial due to their low effectiveness and high toxicity. As a consequence of the adverse reactions, oral treatments frequently have to be discontinued [2]. The limitations of existing therapies encourage the search for alternative new drugs for both the acute and chronic treatment of Chagas’ disease. T. cruzi has a complex life cycle, alternating between the insect vector and the mammalian vertebrate host, which may include humans. The parasite presents different stages during the cycle: epimastigotes (replicative and noninfective forms in the insect vector), bloodstream and metacyclic
Actions of a Proline Analogue, L-Thiazolidine-4-Carboxylic Acid (T4C), on Trypanosoma cruzi
Anahí Magdaleno, Il-Young Ahn, Lisvane Silva Paes, Ariel M. Silber
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0004534
Abstract: It is well established that L-proline has several roles in the biology of trypanosomatids. In Trypanosoma cruzi, the etiological agent of Chagas' disease, this amino acid is involved in energy metabolism, differentiation processes and resistance to osmotic stress. In this study, we analyzed the effects of interfering with L-proline metabolism on the viability and on other aspects of the T. cruzi life cycle using the proline analogue L- thiazolidine-4-carboxylic acid (T4C). The growth of epimastigotes was evaluated using different concentrations of T4C in standard culture conditions and at high temperature or acidic pH. We also evaluated possible interactions of this analogue with stress conditions such as those produced by nutrient starvation and oxidative stress. T4C showed a dose-response effect on epimastigote growth (IC50 = 0.89±0.02 mM at 28°C), and the inhibitory effect of this analogue was synergistic (p<0.05) with temperature (0.54±0.01 mM at 37°C). T4C significantly diminished parasite survival (p<0.05) in combination with nutrient starvation and oxidative stress conditions. Pre-incubation of the parasites with L-proline resulted in a protective effect against oxidative stress, but this was not seen in the presence of the drug. Finally, the trypomastigote bursting from infected mammalian cells was evaluated and found to be inhibited by up to 56% when cells were treated with non-toxic concentrations of T4C (between 1 and 10 mM). All these data together suggest that T4C could be an interesting therapeutic drug if combined with others that affect, for example, oxidative stress. The data also support the participation of proline metabolism in the resistance to oxidative stress.
Kilómetro cero: la construcción del universo simbólico del camino en la Argentina de los a?os treinta
Ballent,Anahí;
Bolet?-n del Instituto de Historia Argentina y Americana Dr. Emilio Ravignani , 2005,
Abstract: the article focuses on the creation and the initial works of the national agency for roads within the ministry of public works in order to examine several aspects of the social process of construction of representations of the road and highway system in the 1930s. in the first place, the article analyzes the agents -aboye all the state and the non government public organizations- and the public polices which intervened in it. second, it examines the territorial dimension of those representations, taking as its center the relationship between the automobile, the road, and the national territory.
Efectos formativos de la modalidad residencial e intensiva
Anahí Mastache
Praxis Educativa , 2010,
Abstract: El Postítulo en Análisis y Animación Socio- Institucional, dise ado y coordinado por la Lic. Lidia Fernández, se propuso la formación de profesores de Institutos de Formación Docente para el rol de "extensionistas". El dise o curricular puso el eje en el trabajo en laboratorios residenciales intensivos. La "convivencia obligada", la acumulación de horas de trabajo intensivo a lo largo de la semana, así como la "intensidad" del tiempo vivido como consecuencia del alto grado de involucramiento personal requerido por la tarea, permitieron la aparición y el análisis de fenómenos peculiares que produjeron efectos formativos de alto interés. En la primera parte voy a hacer foco en las huellas formativas que estos fenómenos han tenido en los docentes participantes. En la segunda parte, me voy a centrar en el impacto de estos mismos fenómenos en la dinámica del equipo coordinador y en las condiciones requeridas para el ejercicio de esta tarea.
Efectos formativos de la modalidad residencial e intensiva. Segunda parte
Anahí MASTACHE
Praxis Educativa , 2011,
Abstract: El Postítulo en Análisis y Animación Socio- Institucional, dise ado y coordinado por la Lic. Lidia Fernández, se propuso la formación de profesores de Institutos de Formación Docente para el rol de "extensionistas". El dise o curricular puso el eje en el trabajo en laboratorios residenciales intensivos. La "convivencia obligada", la acumulación de horas de trabajo intensivo a lo largo de la semana, así como la "intensidad" del tiempo vivido como consecuencia del alto grado de involucramiento personal requerido por la tarea, permitieron la aparición y el análisis de fenómenos peculiares que produjeron efectos formativos de alto interés. En la primera parte me refería a las huellas formativas que estos fenómenos han tenido en los docentes participantes. En esta segunda parte, en cambio, me voy a centrar en el impacto de estos mismos fenómenos en la dinámica del equipo coordinador y en las condiciones requeridas para el ejercicio de esta tarea.
Kilómetro cero: la construcción del universo simbólico del camino en la Argentina de los a os treinta
Anahí Ballent
Bolet?-n del Instituto de Historia Argentina y Americana Dr. Emilio Ravignani , 2005,
Abstract: El artículo toma como objeto la creación y la obra inicial de la Dirección Nacional de Vialidad dentro del Ministerio de Obras Públicas. Se trata de examinar diversos aspectos del proceso social de construcción de representaciones alrededor de la red vial en la década de 1930, mediante el análisis de la trama de actores -sobre todo el Estado y las organizaciones públicas no estatales- y de políticas públicas que intervinieron en él y de la dimensión territorial de esas representaciones, tomando como centro la vinculación entre automóvil, camino y territorio nacional. The article focuses on the creation and the initial works of the National Agency for Roads within the Ministry of Public Works in order to examine several aspects of the social process of construction of representations of the road and highway system in the 1930s. In the first place, the article analyzes the agents -aboye all the State and the non government public organizations- and the public polices which intervened in it. Second, it examines the territorial dimension of those representations, taking as its center the relationship between the automobile, the road, and the national territory.
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