Los cambios de la acumulación de capital a nivel mundial y los procesos regionales de integración: un análisis de los distintos enfoques teóricos; Alterações no Acúmulo de Processo de Capitais a Nível Mundial e Integração Regional: uma análise das diferentes abordagens teóricas Guevara, Sebastian Luis Desde la década de 1970 se fue desarrollando una acelerada transformación de las condiciones en las cuales la sociedad produce su vida (organización de los procesos de trabajo, modos de la circulación de la producción, formas políticas de organización y regulación de la vida social, etc.). Esta transformación ha sido conceptualizada de distintas maneras, de acuerdo a las diversas perspectivas teóricas. La integración regional ha desarrollado una nueva forma y cobró un nuevo ímpetu en los últimos 40 años, como parte de ese proceso de transformación. En este trabajo se sistematizan y ponen en discusión distintas respuestas teóricas que se fueron desarrollando para explicar estos fenómenos de integración regional, focalizando especialmente en el caso del Mercado Común del Sur. Es decir que se presentan y discuten los planteos que analizan la integración regional desde el punto de vista del comercio internacional; aquellos que lo analizan desde la relación entre los Estados nacionales; aquellos que lo entienden como una herramienta para el desarrollo económico (neo-estructuralismo) y; aquellos que lo analizan desde el punto de vista de la unidad del proceso de producción social (entendiendo a la acumulación de capital como un proceso esencialmente global). El trabajo se ubica en esta última perspectiva la cual, a su vez, es puesta en discusión a través de la diferenciación de distintas perspectivas a su interior.; Since the 1970's was developing the rapid transformation of the conditions under which the soiety produces its life (organization of work processes, circulation patterns of production, political forms of organization and regulation of social life, etc. ). This transformation has been conceptualized in different ways according to different theoretical perspectives. Regional integration has developed a new way and gained a new momentum in the last 40 years as part of that process of transformation. In this paper we systematize and call into question various theoretical responses that have been developed to explain these phenomena of regional integration, focusing especially in the case of the Southern Common Market. This means that present and discuss the postures that analyze regional integration from the point of view of international trade from those who analyze the relationship between nation states, those who understand it as a tool for economic development (neo-structuralism ) and, those that analyze it from the point of view of the unity of the social production process (understanding the accumulation of capital as an essentially global.) The work is located in the latter perspective which, in turn, is put into discussion through the differentiation of different perspectives within it.

Altered phenotype and functionality of circulating immune cells characterize adult patients with nonalcoholic steatohepatitis Inzaugarat, Maria Eugenia; Ferreyra Solari, Nazarena Eugenia; Billordo, Luis Ariel; Abecasis, Raquel; Gadano, Adrián Carlos; Cherñavsky, Alejandra Claudia Nonalcoholic steatohepatitis (NASH) is a chronic inflammatory liver disease associated with insulin resistance and its metabolic consequences. Leukocyte mobilization, intrahepatic activation, and an exacerbated production of reactive oxygen species (ROS) and cytokines contribute to the development of NASH. Though alterations in peripheral blood (PB) T cell proportions and functionality remain unidentified, they might play a main role in NASH progression. We have compared the phenotype and Th1/Th2 commitment of peripheral immune cell reservoirs in adult patients and controls as well as the ability of neutrophils and monocytes to handle an ex vivo challenge. Also, we correlated those parameters with the main histological characteristics in NASH. Compared with controls, patients showed increased numbers of CD4 + cells and both CD4 + and CD8 + CD45RO subsets together with a higher frequency of IFN-γ-producing CD4 + and CD8 + T cells. We also found a decreased number of CD4 + and CD8 + CD45RA subsets. The distinctive production of IFN-γ highlights the significance of the observed skewed frequencies of PB T cells. Whereas ROS production by monocytes from NASH patients did not differ from controls, circulating neutrophils displayed a particularly higher phorbol myristate acetate-induced production of ROS. A negative correlation between oxidative burst and fibrosis grade was observed. This study reveals the presence of a characteristic profile of peripheral immune cells in NASH. We also discuss the probable influence of obesity on some of our present findings.

Recuperación de la entrada original del Palacio Muncipal Schavelzon Chavin, Daniel Gaston; Romano, Samanta; Borracci, Lorena Recuperación de la entrada original del Palacio Muncipal

Chondrichthyan egg cases from the south-west Atlantic Ocean Mabragaña, Ezequiel; Figueroa, Daniel Enrique; Scenna, Lorena Beatriz; Díaz de Astarloa, Juan Martín; Colonello, Jorge Horacio; Delpiani, Gabriela Elina Egg cases of 21 oviparous chondrichthyan species from the south-west Atlantic Ocean are described and compared. The catshark Schroederichthys bivius has a cigar-shaped egg case with curled tendrils only at the posterior end. Egg cases of the elephant fish Callorhinchus callorynchus are spindle-shaped with anterior and posterior tubular extensions and lateral flanges. The skate Amblyraja doellojuradoi presents medium-sized egg cases (71 mm in length) with a lateral keel extending to the first portion of the horns. The endemic skate species of the genus Atlantoraja have medium to large egg cases (69-104 mm in length) and present relatively large posterior horns. Egg cases of the genus Bathyraja have a medium size, 75-98 mm in length, and are characterized by a very similar morphology, a relatively smooth to rough surface case and posterior horns strongly curved inwards. Egg cases of the genera Dipturus and Zearaja are very large, 115-230 mm in length, and have a well-developed posterior apron. Despite the problematical identification of skates at species level, the egg capsules of the endemic genus Psammobatis are easily diagnosed; the capsules are small (25-53 mm in length), those of Psammobatis rutrum being the smallest known to date in the world. Egg cases of Rioraja agassizi have a medium size, 61-68 mm in length, relatively straight sides, a smooth surface and silky attachment fibres placed in the lateral keel next to each horn. Those of the genus Sympterygia are small to medium sized, 51-86 mm in length, and display the thickest lateral keel and the longest posterior horns among the skates of the world. Egg cases can be a useful tool for identifying species and egg-laying areas; therefore, a provisional key for the south-west Atlantic Ocean chondrichthyan capsules is presented.

Tensiones entre el emprendedorismo y la autogestion: El papel de las políticas públicas en ese recorrido; Contradictions between entrepreneurship and self management: the public policies role in this relationship Rodriguez, Maria Carla; Ciolli, Vanesa Paola Autogestión y emprendedorismo responden a experiencias históricas y perspectivas sociopolíticas diferentes. Sin embargo, a la luz de la crisis del 2001, en Argentina proliferaron iniciativas orientadas a satisfacer distintas necesidades sociales, a través de la organización, la participación y el desarrollo de prácticas autogestionarias, que emparentaron ambas conceptualizaciones. El presente artículo indaga en los significados constituidos históricamente sobre ambos conceptos con el fin de analizar las experiencias actuales, cuyo carácter y significado se  constituyó como un campo en disputa, entre, por un lado la búsqueda orientada hacia un nuevo modelo social y productivo basado en relaciones sociales no capitalistas y, por otro, alternativas dirigidas a palear el empobrecimiento en el marco del sistema capitalista. Disputa que cobra particular resonancia en el actual contexto regional latinoamericano. El análisis retoma una serie de investigaciones empíricas -realizadas y en curso- en distintas cooperativas de trabajo y vivienda que actualmente funcionan en el Área Metropolitana de Buenos Aires. En esta oportunidad, la exploración de su praxis, subjetividades emergentes y perspectivas sociopolíticas se realizan a partir de la caracterización de las interacciones entre el Estado y las organizaciones sociales en los procesos de diseño y ejecución de políticas públicas.

¿“Damas gratis y pibes chorros”?: Interceptando prácticas y representaciones sobre mujeres y varones jóvenes de sectores populares Silba, Malvina Leonor El presente trabajo tiene como objetivo deconstruir ciertas afirmaciones del sentido común hegemónico sobre las mujeres y varones jóvenes de sectores populares en Argentina. Dichos discursos suelen ser construidos sobre el prejuicio y no sobre el conocimiento de los deseos, expectativas y elecciones de este grupo social. La inclusión de las variables de clase social, edad y género es fundamental para entender los diversos y complejos emplazamientos de los mismos y su relación con las representaciones que sobre ellos se forman. Para cumplir con estos objetivos, propongo repasar la construcción de estos discursos, a los que defino como estigmatizantes, para luego contrastar dichas afirmaciones con las prácticas de un grupo de mujeres y varones jóvenes con los que compartí una experiencia etnográfica, participando de momentos de su vida cotidiana en el barrio y en los lugares bailables a los que asisten los fines de semana.; This article intends to deconstruct certain hegemonic common sense statements about young women and men from popular sectors in Argentina. Such discourse is usually based on bias rather than knowledge about these subjects’ practices, desires, expectations and choices. Also, the inclusion of these social class, age and gender variables is essential to understand their complex and varied social positionings and how they are related to their representations. To meet these goals, in the first place I propose to review these discourses, which I define as stigmatizing, and in the second place, to contrast such statements with the practices of a group of young people with whom I shared an ethnographic experience, participating in some moments of their everyday life in their neighborhood and in the dancing places they attend on weekends.

Glosis de Roxana Carrizo Longoni, Ana Intuyo que la clave de la poética de Roxana Carrizo es la convicción de que existe una lengua secreta, tan secreta que ni la misma poeta la conoce porque es secreta para todos. Para la poeta hablar es en cierta forma hacer trampa a esa certidumbre: un sortilegio o un conjuro contra esas palabras que no se conocen, porque las conocidas nunca alcanzan a decir lo indecible. Hablar es tener algo que ocultar (lo contrario a pensar que callar es dejar de decir lo que se sabe). La revista Plebella está indexada por Latindex: http://www.latindex.unam.mx/

Uniformity of rotavirus strain nomenclature proposed by the Rotavirus Classification Working Group (RCWG) Matthijnssens, Jelle; Ciarlet, Max; McDonald, Sarah M.; Attoui, Houssam; Bányai, Krisztián; Brister, J. Rodney; Buesa, Javier; Esona, Mathew D.; Estes, Mary K.; Gentsch, Jon R.; Iturriza Gómara, Miren; Johne, Reimar; Kirkwood, Carl D.; Martella, Vito; Mertens, Peter P. C.; Nakagomi, Osamu; Parreño, Gladys Viviana; Rahman, Mustafizur; Ruggeri, Franco M.; Saif, Linda J.; Santos, Norma; Steyer, Andrej; Taniguchi, Koki; Patton, John T.; Desselberger, Ulrich; van Ranst, Marc In April 2008, a nucleotide-sequence-based, complete genome classification system was developed for group A rotaviruses (RVs). This system assigns a specific genotype to each of the 11 genome segments of a particular RV strain according to established nucleotide percent cutoff values. Using this approach, the genome of individual RV strains are given the complete descriptor of Gx-P[x]-Ix-Rx-Cx-Mx-Ax-Nx-Tx-Ex-Hx. The Rotavirus Classification Working Group (RCWG) was formed by scientists in the field to maintain, evaluate and develop the RV genotype classification system, in particular to aid in the designation of new genotypes. Since its conception, the group has ratified 51 new genotypes: as of April 2011, new genotypes for VP7 (G20-G27), VP4 (P[28]-P[35]), VP6 (I12-I16), VP1 (R5-R9), VP2 (C6-C9), VP3 (M7-M8), NSP1 (A15-A16), NSP2 (N6-N9), NSP3 (T8-T12), NSP4 (E12-E14) and NSP5/6 (H7-H11) have been defined for RV strains recovered from humans, cows, pigs, horses, mice, South American camelids (guanaco), chickens, turkeys, pheasants, bats and a sugar glider. With increasing numbers of complete RV genome sequences becoming available, a standardized RV strain nomenclature system is needed, and the RCWG proposes that individual RV strains are named as follows: RV group/species of origin/country of identification/common name/year of identification/G- and P-type. In collaboration with the National Center for Biotechnology Information (NCBI), the RCWG is also working on developing a RV-specific resource for the deposition of nucleotide sequences. This resource will provide useful information regarding RV strains, including, but not limited to, the individual gene genotypes and epidemiological and clinical information. Together, the proposed nomenclature system and the NCBI RV resource will offer highly useful tools for investigators to search for, retrieve, and analyze the ever-growing volume of RV genomic data.

La cultura italiana en traducción Perez Carrasco, Mariano En este artículo realizo algunas observaciones críticas acerca de un amplio grupo de libros de literatura y filosofía italianas recientemente traducidos al castellano (2010-2011). El artículo comienza con el análisis de la traducción (por primera vez al castellano) de los textos literarios de Maquiavelo; luego describe las traducciones de las poesías de Gesualdo Bufalino (La amarga miel), y de Leopardi y Ungaretti (Secreto del poeta). El artículo expone también el contenido y el trabajo de traducción llevado a cabo en el volumen La cuestión de los universales en la Edad Media, de A. Tursi y M.F. Marchetto, que contiene textos de Porfirio, Boecio y Abelardo. También la obra de Giorgio Agamben (varias veces traducida al castellano) tiene un capítulo especial. El artículo finaliza con un comentario acerca de los blogs dedicados a la traducción de literatura y filosofía italianas, y con una reflexión acerca de la recepción de la literatura y filosofía italianas en nuestro país.

El pesimismo histórico en la filosofía de Denis Diderot Ratto, Gustavo Adrián Los especialistas suelen atribuir a Diderot una concepción pesimista de la historia. Si bien de las obras de madurez del editor de la Encyclopédie se desprende una oscura imagen del porvenir, producto entre otras cosas de su encuentro con Catherine II y de la influencia de Galiani, ese pesimismo parece no agotar sus reflexiones acerca de la historia. De los trabajos de la época anterior a su viaje a Rusia se desprende otra concepción de la historia, la cual, no obstante, no se confunde con las cándidas especulaciones acerca del futuro del marqués de Condorcet.; Specialists commonly ascribe to Diderot a pessimistic conception of history. While the mature work of the editor of the Encyclopédie conveys an obscure image of the future, resulting, inter alia, from his encounter with Catherine II and from Galiani's influence, such pessimism never appears to exhaust his reflections on history. His work prior to his trip to Russia reveals another perception of history wich, nevertheless, is clearly distinct from the Marquis of Condorcet´s candid speculations about the future.

Antioxidant response of three Tillandsia species transplanted to urban, agricultural, and industrial areas Bermudez, Gonzalo Miguel Angel; Pignata, Maria Luisa To evaluate the physiological response of Tillandsia capillaris Ruiz & Pav. f. capillaris, T. recurvata L., and T. tricholepis Baker to different air pollution sources, epiphyte samples were collected from a noncontaminated area in the province of Córdoba (Argentina) and transplanted to a control site as well as three areas categorized according to the presence of agricultural, urban, and industrial (metallurgical and metal-mechanical) emission sources. A foliar damage index (FDI) was calculated with the physiological parameters chlorophyll a, chlorophyll b, malondialdehyde (MDA), hydroperoxyconjugated dienes, sulfur (S) content, and dry weight-to-fresh weight ratio. In addition, electrical conductivity (E-cond), relative water content (RWC), dehydration kinetics (Kin-H 2O), total phenols (T-phen), soluble proteins (S-prot), and activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase were determined. The parameters E-cond, FDI, SOD, RWC, and Kin-H 2O can serve as suitable indicators of agricultural air pollution for T. tricholepis and T. capillaris, and CAT, Kin-H 2O, and SOD can do the same for T. recurvata. In addition, MDA, T-phen, and S-prot proved to be appropriate indicators of urban pollution for T. recurvata. Moreover, FDI, E-cond, and SOD for T. recurvata and MDA for T. tricholepis, respectively, could be used to detect deleterious effects of industrial air pollution.

Real-Space Mapping of Fano Interference in Plasmonic Metamolecules Alonso Gonzalez, Pablo; Schnell, Martin; Sarriugarte, Paulo; Sobhani, Heidar; Wu, Chihhui; Arju, Nihal; Khanikaev, Alexander; Golmar, Federico; Albella, Pablo; Arzubiaga, Libe; Casanova, Felix; Hueso, Luis E.; Nordlander, Peter; Shvets, Gennady; Hillenbrand, Rainer An unprecedented control of the spectral response of plasmonic nanoantennas has recently been achieved by designing structures that exhibit Fano resonances. This new insight is paving the way for a variety of applications, such as biochemical sensing and surface-enhanced Raman spectroscopy. Here we use scattering-type near-field optical microscopy to map the spatial field distribution of Fano modes in infrared plasmonic systems. We observe in real space the interference of narrow (dark) and broad (bright) plasmonic resonances, yielding intensity and phase toggling between different portions of the plasmonic metamolecules when either their geometric sizes or the illumination wavelength is varied.

Long term effects of fire on ectomycorrhizas and soil properties in Nothofagus pumilio forests in Argentina Longo, Maria Silvana; Urcelay, Roberto Carlos; Nouhra, Eduardo Ramon The forests of Nothofagus pumilio have historically been affected by forest fires. The effects of fire on certain above and belowground, biotic and abiotic components of these ecosystems have been previously documented, albeit belowground components have received much less attention. It has been suggested that the effects observed in the short-term after a fire usually differ from the longer-term effects. The long-term effects of fire (i.e. >5 years after burning) on belowground components in Nothofagus forests are currently unknown. In the present study we evaluated the long-term effect of fire on ectomycorrhiza (ECM) colonization and morphotype composition in N. pumilio roots, as well as soil chemical properties in temperate forests in Patagonia. Sampling was conducted in three mature monospecific forests. In each, nearby burned and unburned sites were selected. The time since the occurrence of fires differed between areas (i.e. 6?10 years). Within each site, 3 transects of 40 m were established randomly along which 5 samples of roots and soil were collected in spring and autumn. The main results were: (1) in comparison with the unburned site, ECM colonization was lower in the burned site in the area with the shorter time length since fire occurrence and no effects in the other two areas were observed; (2) richness and diversity were not significantly affected by fire but there was a significant effect of season for both parameters, being higher in spring; (3) ECM dominance was significantly higher in the unburned than in the burned site in Tronador, while in Challhuaco the opposite was observed, mainly in autumn; (4) in general carbon, nitrogen and phosphorous decreased while pH increased in the burned sites; (5) ECM colonization positively correlated with NH4+ and phosphorus and negatively with pH but was not significantly correlated with organic matter or any other soil variable. Altogether the results suggest that effects of fire on ectomycorrhiza and soil properties in N. pumilio forests are probably related to the time elapsed since fire occurrence combined with site characteristics. In addition, the direct and indirect effects of fire in these forest systems may persist for more than 10 years.

The Amblyomma (Acari: Ixodida: Ixodidae) of Mexico: identification keys, distribution and hosts Guzmán Cornejo, Carmen; Robbins, Richard G.; Guglielmone, Alberto Alejandro; Montiel Parra, Griselda; Pérez, Tila María Taxonomic keys, distributional data and hosts are provided for the 26 Amblyomma species known from Mexico. Members of this genus have been collected in 30 of Mexico’s 32 states and are associated with 43 nominal vertebrate taxa, of which 40 have been identified to species and four (Python sp., Myrmecophaga tridactyla, Tamandua tetradactyla, Tupinambis teguixin) are non-native. Mammals are the principal class of vertebrates parasitized by Mexican Amblyomma species, followed by reptiles, birds and amphibians. Our knowledge of Mexican Amblyomma is still far from complete because many potential hosts have not yet been examined and vast areas of the country remain unexplored.

Ru/La2O3–SiO2 catalysts for hydrogen production in membrane reactors Faroldi, Betina María Cecilia; Lombardo, Eduardo Agustin; Cornaglia, Laura Maria Binary La2O3–SiO2 supports were employed to obtain active, stable Ru catalysts with high dispersions for the dry reforming of methane. Supports with 15, 27, 40 and 50 wt.% of La2O3 were prepared by incipient wetness impregnation of La(NO3)3 on SiO2. The Ru loading was 0.6 wt.% for all catalysts. The solids were evaluated in a fixed-bed reactor under differential conditions. Previously, they were reduced at 550 ◦C. All the formulations were stable for at least 100 h on stream. Subsequently, the most active catalyst (Ru/La2O3(50)–SiO2) was tested in a membrane reactor using different feed mixtures with and without O2. The reactor configuration was formed by a fixed-bed reactor followed by a membrane reactor. The methane conversion increased when the CO2/CH4 ratio increased from 1.0 to 1.9 and when oxygen was added to the feed. Operating under conditions of combined reforming (oxygen addition) and CO2/CH4 ratio equal to 1, a high production of hydrogen was also achieved in the membrane reactor.

Effect of the organochlorine pesticide endosulfan on GnRH and gonadotrope cell populations in fish larvae Piazza, Yanina Grisel; Pandolfi, Matias; Lo Nostro, Fabiana Laura Endocrine-disrupting chemicals can influence the hypothalamus-pituitary- gonad axis and possibly affect reproduction in vertebrates. We analyzed the effect of 30-day endosulfan (ES) exposure in sexually undifferentiated larvae of the cichlid fish Cichlasoma dimerus. The number, area, mean cytoplasmic and nuclear diameter, and mean cytoplasmic optical density of gonadotropin-releasing hormone (GnRH) I, II, and III immunoreactive (ir-) neurons and β follicle-stimulating hormone (βFSH) ir-cells were measured. Animals exposed to the highest ES concentration (0.1 μg/l) showed a decrease in GnRH I nucleus/cytoplasm area ratio upon exposure. Nuclear area and mean nuclear diameter of βFSH ir-cells was higher in ES treated fish. βFSH nucleus/cytoplasm area ratio was high in exposed animals, and animals exposed to 0.1 μg/l ES showed smaller mean cytoplasmic optical density. These findings suggest that ES affects GnRH I and βFSH protein synthesis/release. However, these responses seem to be insufficient to affect gonadal differentiation at this stage of development.

Effect of indigenous mycorrhizal colonization on phosphorus-acquisition efficiency in soybean and sunflower Fernández, Mariana Cecilia; Gutiérrez Boem, Flavio Hernán; Rubio, Gerardo Despite a general consent about the beneficial contribution of arbuscular mycorrhizal fungi (AMF) on natural ecosystems, there is an intense debate about their role in agricultural systems. In this work, soybean (Glycine max L.) and sunflower (Helianthus annuus L.) field plots with different P availabilities were sampled across the Pampean Region of Argentina (> 150 samples from Mollisols) to characterize the relationship between available soil P and indigenous mycorrhizal colonization. A subsequent pot experiment with soybean and sunflower was carried out to evaluate the effect of P supply (0, 12, and 52 mg Pkg -1) and AMF inoculation on AMF colonization and crop responsiveness to P in a Mollisol. Both crops showed high AMF colonization in the field (average: 55% for soybean and 44% for sunflower). While mycorrhizal colonization in soybean was significantly and negatively related to available soil P, no such trends were apparent in sunflower. Also, total biomass was 3.5 and 2.0 times higher in mycorrhizal than in nonmycorrhizal pot-grown soybean under low- and medium-P conditions, respectively. Sunflower, on the other hand, did not benefit from AMF symbiosis under medium and high P supply. While mycorrhization stimulated P-uptake efficiency in soybean, the generally high P efficiency in sunflower was not associated with AMF symbiosis.

Habitat specificity can blur the predictions of species-energy theory: A case study of tenebrionid beetles adapted to aridity Carrara, Rodolfo; Vazquez, Diego P.; Flores, Gustavo Ernesto Species-energy theory predicts a positive relationship between species richness and energy. The mechanism assumed by this theory is that high energy promotes high population abundance, which in turn promotes high species richness. Evaluations of this mechanism have rendered conflicting evidence, suggesting that more effort is needed to understand the theory's limitations. Several studies have addressed these limitations, contributing to expand the theory's scope by incorporating energy variation, whereas others have demonstrated scale dependence of the more individuals hypothesis. We propose that another limitation of this theory is related to its application to groups of species with strong habitat specificity. We suggest that the expected relationship between energy and richness is not necessarily positive at large scales for groups of species adapted to harsh environments. Using data on tenebrionid beetles from arid areas of southern South America, we contrasted four hypotheses that lead to contrasting predictions about the strength and direction of the species-energy relationship on tenebrionid richness. We found a negative relationship between richness and energy availability. We propose that this negative relationship is the result of a constraint in the mechanisms assumed by species-energy theory because organisms evolve adaptations to survive climatic harshness, which influences population abundances.

Actualización en el tratamiento del síndrome urémico hemolítico endémico: Patogénesis y tratamiento de la complicación sistémica más grave de las infecciones por Escherichia coli productor de toxina Shiga; Update on the treatment of endemic hemolytic uremic syndrome. Pathogenesis and treatment of the most severe systemic complication of infections by Shiga toxin-producing Escherichia coli Fernández Brando, Romina Jimena; Bentancor, Leticia Verónica; Mejias, María Pilar; Panek, Cecilia Analía; Cabrera, Gabriel Gustavo; Exeni, Ramón A.; Palermo, Marina Sandra La forma típica o post-diarreica del síndrome urémico hemolítico (SUH) es la complicación más grave de las infecciones por cepas de Escherichia coli productoras de toxina Shiga (STEC). En la Argentina el SUH es un problema crítico de salud pública, ya que representa la principal causa de falla renal aguda en la infancia, la segunda causa de falla renal crónica, y aporta el 20% de los casos de transplante renal durante la infancia y la adolescencia. A pesar de los avances en el conocimiento de su patogénesis, el único tratamiento actual de los pacientes con SUH es de sostén, y no existen terapias específicas ni preventivas. En la presente revisión expondremos los conocimientos básicos de los mecanismos patogénicos y discutiremos los enfoques terapéuticos tradicionales e innovadores, con especial foco en la situación nacional y los aportes hechos por grupos de la Argentina.; The typical form of hemolytic uremic syndrome (HUS) is the major complication of Shiga toxin-producing Escherichia coli (STEC) infections. HUS is a critical health problem in Argentina since it is the main cause of acute renal failure in children and the second cause of chronic renal failure, giving account for 20% of renal transplants in children and adolescents in our country. In spite of the extensive research in the field, the mainstay of treatment for patients with HUS is supportive therapy, and there are no specific therapies preventing or ameliorating the disease course. In this review, we present the current knowledge about pathogenic mechanisms and discuss traditional and innovative therapeutic approaches, with special focus in national status and contributions made by Argentinean groups.

Study of the water-gas shift reaction over Pt supported on CeO2–ZrO2 mixed oxides Vignatti, Charito Ivana; Avila, Maria Sol; Apesteguia, Carlos Rodolfo; Garetto, Teresita Francisca The water gas shift (WGS) reaction was studied on Pt/CeO2, Pt/ZrO2 and Pt/CexZrx-1O2 catalysts. All the samples were characterized by a variety of physical and spectroscopic techniques. The catalysts activities were evaluated at 250°C in a recirculating reactor through CO conversion versus time test and also by in situ diffuse reflection infrared Furier transform spectroscopy (DRIFT). The samples activity for the WGS reaction depended on chemical composition. Pt/CexZrx-1O2 catalysts with x≥0.5 were more active than Pt/CeO2, probably because the addiction of Zr to ceria increased both the surface area and the reducibility of ceria. The lowest CO conversion rates were obtained on Pt/ZrO2 and Zr-rich Pt/CexZrx-1O2 samples. Based on DRIFT experiments, this result was interpreted by considering that in the WGS formate associative mechanism the stability of formats species is higher on Zr-rich supports.