Crescimento individual de Drepanotrema cimex (Moricand, 1839) (Pulmonata, Planorbidae) de Arenalcito, Reserva Natural de Usos Múltiples “Isla Martín García”, Argentina

The species of the genus Drepanotrema, most of them endemic to the Neotropical region, belong to the Planorbidae. Of the nine species of this genus, six are found in Argentina. The present investigation analysed the individual growth of Drepanotrema cimex in Arenalcito pond (34°11’ S, 58°15’ W), Martín García Island Natural Reserve of Multiple Uses, Buenos Aires Province, Argentina. A total of 14 samples were collected (n = 1931) from February 2006 to June 2007. Five environmental variables were measured: water temperature, dissolved oxygen (mg L-1), electrical conductivity (S cm-1), total dissolved solids, and pH. The individual growth of the species was analysed mathematically by means of the von Bertalanffy equation, where: Lt = 5,6(1-e-2,0592 (t-0,293)). The parameter L was estimated by the Ford-Walford Method. The population of D. cimex was characterised by a complex and dynamic size structure throughout the annual cycle. The analysis of the curves revealed unimodal (2006) and polymodal (April to June 2007) distributions, which pattern served to identify the existence of cohorts within the population studied.As espécies do gênero Drepanotrema, a maioria delas endêmicas da região Neotropical, pertencem ao Planorbidae. Das nove espécies desta família, seis são encontradas na Argentina. Este artigo analisa o crescimento individual de Drepanotrema cimex na lagoa de Arenalcito, Reserva Natural de Usos Múltiples Ilha Martín García, Buenos Aires, Argentina (34°11’ S - 58°15’ W). A amostragem foi realizada entre fevereiro de 2006 e junho de 2007. Durante o curso das campanhas foram obtidas 14 amostras (n = 1931). Cinco variáveis ambientais foram medidas: temperatura da água, oxigênio dissolvido (mg L-1), condutividade elétrica (uS cm-1), sólidos dissolvidos e pH. O crescimento individual das espécies foi analisada matematicamente por meio da equação de von Bertalanffy em que: Lt = 5,6 (1-e-2, 0592 (t-0, 293)). O paràmetro L foi estimada pe lo método de Ford-Walford. A população de D.cimex foi caracterizada por uma estrutura complexa e dinâmica de tamanho ao longo do ciclo anual. A análise das curvas mostrou distribuições unimodais (2006) e polimodais (abril-junho 2007), identificando a existência de coortes na população estudada.Fil: Martín, Stella Maris. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. División de Zoología Invertebrados; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; ArgentinaFil: Díaz, Ana Carolina. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. División de Zoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Rumi, A.. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. División de Zoología Invertebrados; Argentin

Modelo de negocio y estrategia editorial: el caso del wsj.com

La investigación sobre modelos de negocios en la industria de la comunicación se ha caracterizado por un elevado grado de experimentación y la ausencia de respuestas unívocas al problema de la rentabilidad de los contenidos digitales. En este escenario, The Wall Street Journal suele ser mencionado como un referente del modelo de suscripción. Este artículo demuestra empíricamente que el modelo del diario económico más prestigioso del mundo ofrece un modelo híbrido en el que los contenidos gratuitos representan el 73% del total publicado en la portada del wsj.com y analiza cuáles son las características comunes que suelen compartir aquellos contenidos de pago frente a las compartidas por los contenidos gratuitos

Noninvasive assessment of an engineered bioactive graft in myocardial infarction: impact on cardiac function and scar healing

Cardiac tissue engineering, which combines cells and biomaterials, is promising for limiting the sequelae of myocardial infarction (MI). We assessed myocardial function and scar evolution after implanting an engineered bioactive impedance graft (EBIG) in a swine MI model. The EBIG comprises a scaffold of decellularized human pericardium, green fluorescent protein-labeled porcine adipose tissue-derived progenitor cells (pATPCs), and a customized-design electrical impedance spectroscopy (EIS) monitoring system. Cardiac function was evaluated noninvasively by using magnetic resonance imaging (MRI). Scar healing was evaluated by using the EIS system within the implanted graft. Additionally, infarct size, fibrosis, and inflammation were explored by histopathology. Upon sacrifice 1 month after the intervention, MRI detected a significant improvement in left ventricular ejection fraction (7.5%64.9% vs. 1.4%63.7%; p = .038) and stroke volume (11.565.9 ml vs. 364.5 ml; p = .019) in EBIG-treated animals. Noninvasive EIS data analysis showed differences in both impedance magnitude ratio (20.02 6 0.04 per day vs. 20.48 6 0.07 per day; p = .002) and phase angle slope (20.18°60.24° per day vs.23.52°60.84° per day; p = .004) in EBIG compared with control animals. Moreover, in EBIG-treated animals, the infarct size was 48% smaller (3.4%60.6% vs. 6.5%61%; p = .015), less inflammation was found by means of CD25+ lymphocytes (0.65 6 0.12 vs. 1.26 6 0.2; p = .006), and a lower collagen I/III ratio was detected (0.4960.06 vs. 1.6660.5; p = .019). An EBIG composed of acellular pericardium refilled with pATPCs significantly reduced infarct size and improved cardiac function in a preclinical model of MI. Noninvasive EIS monitoring was useful for tracking differential scar healing in EBIG-treated animals, which was confirmed by less inflammation and altered collagen deposit.Peer ReviewedPostprint (published version

The in vitro antigenicity of Plasmodium vivax rhoptry neck protein 2 (PvRON2) B- and T-epitopes selected by HLA-DRB1 binding profile

Malaria caused by Plasmodium vivax is a neglected disease which is responsible for the highest morbidity in both Americas and Asia. Despite continuous public health efforts to prevent malarial infection, an effective antimalarial vaccine is still urgently needed. P. vivax vaccine development involves analyzing naturally-infected patients' immune response to the specific proteins involved in red blood cell invasion. The P. vivax rhoptry neck protein 2 (PvRON2) is a highly conserved protein which is expressed in late schizont rhoptries; it interacts directly with AMA-1 and might be involved in moving-junction formation. Bioinformatics approaches were used here to select B- and T-cell epitopes. Eleven high-affinity binding peptides were selected using the NetMHCIIpan-3.0 in silico prediction tool; their in vitro binding to HLA-DRB1*0401, HLA-DRB1*0701, HLA-DRB1*1101 or HLA-DRB1*1302 was experimentally assessed. Four peptides (39152 (HLA-DRB1*04 and 11), 39047 (HLA-DRB1*07), 39154 (HLADRB1*13) and universal peptide 39153) evoked a naturally-acquired T-cell immune response in P. vivax-exposed individuals from two endemic areas in Colombia. All four peptides had an SI greater than 2 in proliferation assays; however, only peptides 39154 and 39153 had significant differences compared to the control group. Peptide 39047 was able to significantly stimulate TNF and IL-10 production while 39154 stimulated TNF production. Allele-specific peptides (but not the universal one) were able to stimulate IL-6 production; however, none induced IFN-? production. The Bepipred 1.0 tool was used for selecting four B-cell epitopes in silico regarding humoral response. Peptide 39041 was the only one recognized by P. vivax-exposed individuals' sera and had significant differences concerning IgG subclasses; an IgG2 > IgG4 profile was observed for this peptide, agreeing with a protection-inducing role against P. falciparum and P. vivax as previously described for antigens such as RESA and MSP2. The bioinformatics results and in vitro evaluation reported here highlighted two T-cell epitopes (39047 and 39154) being recognized by memory cells and a B-cell epitope (39041) identified by P. vivax-exposed individuals' sera which could be used as potential candidates when designing a subunit-based vaccine. © 2018 López, Yepes-Pérez, Díaz-Arévalo, Patarroyo and Patarroyo

What is known about the immune response induced by Plasmodium vivax malaria vaccine candidates?

Malaria caused by Plasmodium vivax continues being one of the most important infectious diseases around the world; P. vivax is the second most prevalent species and has the greatest geographic distribution. Developing an effective antimalarial vaccine is considered a relevant control strategy in the search for means of preventing the disease. Studying parasite-expressed proteins, which are essential in host cell invasion, has led to identifying the regions recognized by individuals who are naturally exposed to infection. Furthermore, immunogenicity studies have revealed that such regions can trigger a robust immune response that can inhibit sporozoite (hepatic stage) or merozoite (erythrocyte stage) invasion of a host cell and induce protection. This review provides a synthesis of the most important studies to date concerning the antigenicity and immunogenicity of both synthetic peptide and recombinant protein candidates for a vaccine against malaria produced by P. vivax. © 2017 López, Yepes-Pérez, Hincapié-Escobar, Díaz-Arévalo and Patarroyo

Nuevos modelos de negocio, creación de valor y el cambiante rol de la prensa en los sistemas democráticos

Esta comunicación pretende profundizar en la relación que existe entre una prensa rentable y una democracia sana. La ausencia de un modelo de negocio que haga rentable el trabajo de las redacciones digitales plantea serios interrogantes sobre el modo en que los medios desempeñan tres funciones básicas para la normalidad de los sistemas democráticos: la selección de información, la vigilancia de los poderes políticos y económicos, y la generación del discurso que propicie un debate público. La pérdida de la exclusividad en la difusión de la información, el cuestionamiento de la autoridad de los periodistas como actores independientes y la desfragmentación de los mensajes inherente a internet ha debilitado la propia creación de valor de los medios tradicionales, lo que se ha derivado en una pérdida en la capacidad de generar ingresos por su actividad principal. Desde la investigación sobre modelos de negocios en la industria de la información apenas se ha dado respuesta a este problema, en parte por la escasa uniformidad conceptual, teórica y me-todológica, y en parte por una excesiva orientación hacia uno de los elementos de los modelos de negocio: los ingresos.This paper aims to analyze the relationship between a profitable press and a healthy democracy. The lack of a profitable business model for digital editions raises serious questions about how the media perform three key functions for the normality of democratic systems: selection of information, monitoring of political and economic powers, and generation of discourse that encourages the public debate. The loss of exclusivity in the dissemination of information, questioning the authority of journalists as independent actors, and the defragmentation of messages inherent to internet has undermined the creation of value of traditional media, which has resulted in a loss in the ability to generate income from their main activity. Research on business models in the media industry has barely responded to this problem in part by the limited conceptual, theoretical and methodological uniformity, and in part by an excessive focus on one element of the models business, the incomes

Impaired insulin signaling pathway in ovarian follicles of cows with cystic ovarian disease

Cystic ovarian disease (COD) is an important cause of infertility in dairy cattle. Follicular cell steroidogenesis and proliferation in ovulatory follicles is stimulated by hormones such as insulin and its necessary post-receptor response. The aim of this study was to determine the expression of insulin receptor (IR), IR substrate-1 (IRS1) and phosphatidylinositol 3-kinase (PI3K), key intermediates in the insulin pathway, in control cows and cows with spontaneous COD and ACTH-induced COD. IR and IRS1 mRNA levels were greater in granulosa cells and lower in follicular cysts than in control tertiary follicles. PI3K mRNA levels were similar in all follicles evaluated, whereas the expression of IR, IRS1 and PI3K was similar in theca cells. Protein expression of IR was higher in control tertiary follicles than in the same structures in animals with COD and with cysts. IRS1 and PI3K protein expression showed the same pattern in tertiary and cystic follicles. However, the protein expression of subunit alpha p85 of PI3K was greater in theca cells from tertiary follicles than in cystic follicles. These results provide new insights into the insulin response in cows with COD. The lower gene and protein expressions of some insulin downstream effectors at an early stage of the signaling pathway could negatively influence the functionality of ovaries and contribute to follicle persistence.Fil: Hein, Gustavo Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; Argentina. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfológicas. Laboratorio de Biología Celular y Molecular; ArgentinaFil: Panzani, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; Argentina. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfológicas. Laboratorio de Biología Celular y Molecular; ArgentinaFil: Rodríguez, Fernanda Mariel. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfológicas. Laboratorio de Biología Celular y Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Salvetti, Natalia Raquel. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfológicas. Laboratorio de Biología Celular y Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Díaz, Pablo Uriel. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfológicas. Laboratorio de Biología Celular y Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Gareis, Natalia Carolina. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfológicas. Laboratorio de Biología Celular y Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Benitez, G. A.. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfológicas. Laboratorio de Biología Celular y Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Ortega, Hugo Hector. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfológicas. Laboratorio de Biología Celular y Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; ArgentinaFil: Rey, Florencia. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Ciencias Morfológicas. Laboratorio de Biología Celular y Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; Argentin

Structural evolution of the El Salvador Fault Zone: an evolving fault system within a volcanic arc.

The El Salvador Fault Zone, firstly identifiedafter the 13th February 2001 Mw 6.6 El Salvador earthquake, is a 150 km long,20 km wide right-lateral strike-slip fault system. Ruptures along the ESFZ arethought to be responsible for most of the historical destructive earthquakesalong the El Salvador Volcanic Arc, as well as for most of the currentseismicity of the area. In this work, we focus on the geological setting of thefault zone by describing its geomorphology and structure, using field-based observations,digital terrain modelling, and aerial photograph interpretation with the aim atcontributing to the understanding of the ESFZ slip behaviour. In particular, weaddress the ESFZ structure, kinematics and evolution with time. The ESFZ is a complex set of traces divided inmajor rupture segments characterized by different geometry, kinematics andgeomorphic expressions. Natural fault exposures and paleoseismic trenchesexcavated along the fault show that the strike slip deformation is distributedin several planes. Both geometry and kinematics of the fault zone areconsistent with a transtensional strain regime.The estimated geological slip-rate for the mainfault segments by paleoseismic trenches and displaced geomorphic features impliesa deficit in velocity of the fault compared to the available GPS velocitiesdata. The high vertical scarps of some fault segments would require quaternaryslip rates not coherent neither with measured GPS velocities nor with sliprates obtained from paleoseismic analysis. This mismatch suggests apre-existing graben structure that would be inherited from the previousregional roll back related extensional stage. We consider that the ESFZ isusing this relict structure to grow up along it. As a result, we propose amodel for ESFZ development consistent with all these observations.La Zona de Falla de El Salvador (ZFES) es un sistema de falla de desgarre dextral de 150 km de longitud y 20 de anchura, que fue identificada por primera vez después del terremoto de Mw 6.6 de El Salvador de febrero de 2001. La mayoría de la sismicidad y de los terremotos históricos destructivos producidos en el arco volcánico salvadoreño han sido producidos por la ruptura de la ZFES. Este trabajo se centra en el marco geológico de la zona de falla describiendo su geomorfología y su estructura a través de observaciones de campo, del estudio de los modelos digitales del terreno y de la interpretación de las fotografías aéreas, con el objetivo de avanzar en el conocimiento del comportamiento de la ZFES. En concreto trataremos del estudio de la estructura, la cinemática y la evolución de la ZFES. La ZFES es un complejo sistema de fallas divididas en varios segmentos que se diferencian en la geometría, la cinemática y la expresión geomorfológica. En los afloramientos de la falla, así como en las trincheras paleosismicas excavadas se ha observado que la deformación de desgarre está distribuida en varios planos y tanto la geometría como la cinemática de la zona de falla indican que la ZFES está bajo un régimen de deformación transtensional. La tasa de deformación estimada para los principales segmentos a través del estudio paleosísmico y del análisis de indicadores geomorfológicos desplazados nos muestra un déficit de velocidad para la falla si lo comparamos con los datos obtenidos por GPS. Estos datos tampoco ayudan a explicar la existencia de grandes escarpes verticales que se observan en algunos segmentos de la falla, y que requerirían tasas de deformación muy elevadas. Esta discrepancia sugiere la existencia de una estructura de graben preexistente que puedo ser producida por el “roll-back” de la placa y que creó una fase extensional en el arco volcánico. En este trabajo consideramos que la ZFES está actualmente desarrollándose sobre la estructura extensional relicta y como resultado proponemos un modelo estructural consistente con estas observaciones

MTHFD1 controls DNA methylation in Arabidopsis.

DNA methylation is an epigenetic mechanism that has important functions in transcriptional silencing and is associated with repressive histone methylation (H3K9me). To further investigate silencing mechanisms, we screened a mutagenized Arabidopsis thaliana population for expression of SDCpro-GFP, redundantly controlled by DNA methyltransferases DRM2 and CMT3. Here, we identify the hypomorphic mutant mthfd1-1, carrying a mutation (R175Q) in the cytoplasmic bifunctional methylenetetrahydrofolate dehydrogenase/methenyltetrahydrofolate cyclohydrolase (MTHFD1). Decreased levels of oxidized tetrahydrofolates in mthfd1-1 and lethality of loss-of-function demonstrate the essential enzymatic role of MTHFD1 in Arabidopsis. Accumulation of homocysteine and S-adenosylhomocysteine, genome-wide DNA hypomethylation, loss of H3K9me and transposon derepression indicate that S-adenosylmethionine-dependent transmethylation is inhibited in mthfd1-1. Comparative analysis of DNA methylation revealed that the CMT3 and CMT2 pathways involving positive feedback with H3K9me are mostly affected. Our work highlights the sensitivity of epigenetic networks to one-carbon metabolism due to their common S-adenosylmethionine-dependent transmethylation and has implications for human MTHFD1-associated diseases

Urban sustainability. Tome: A proposal for evaluating chilean general plans

This article values the sustainability in the urban planning through the design of an indicators system, that arise from the identification of the attributes of the Sustainable Urban Planning. The indicators are tried in the proposed land cover model established in the instrument of territorial planning called “Regulator Urban Plan”. The study is applied in the town of “Tomé”, located in the 8th Region “Bío Bío” of Chile. The obtaining of the indicators of urban sustainability is developed from the use of the tools of GIS. The proposed urban planning is evaluated with a system of indicators based on 3 territorial components, that are: Distribution of uses and physical structure, Land use consumption and environmental Quality, and are processed in the zones of the proposed land cover model. The method combines the bibliographical analysis with the application of spatial analysis and geoprocessing in GIS. The results allow to access to us to value the sustainability of the proposed territorial model.Este artículo valora la sostenibilidad en la planificación urbana por medio del diseño de un sistema de indicadores, que surgen de la identificación de los atributos del Planeamiento Urbano Sostenible. Los indicadores se ensayan en el modelo de ocupación del suelo propuesto y establecido en el instrumento de planificación territorial denominado "Plan Regulador Comunal". El estudio se aplica en la localidad de Tomé, ubicada en la VIII Región del Bio Bío de Chile. La obtención de los indicadores de sostenibilidad urbana se desarrolla a partir del uso de las herramientas de Sistemas de Información Geográfica ó SIG. El planeamiento urbano propuesto se evalúa con un sistema de indicadores basados en 3 componentes territoriales que se procesan en la zonficación del suelo urbano propuesto y que son, la distribución de usos y estructura fisica, el consumo de Suelo y la calidad ambiental. El método combina el analisis bibliográfico, con la aplicación de análisis espacial y geoprocesamiento en SIG. Los resultados se aproximan a valorar la sostenibilidad del modelo territorial propuesto