Surveillance studies of Lymphocystis disease virus in farmed gilthead seabream (Sparus aurata) by real-time PCR

Lymphocystis disease (LCD) is the main viral infection reported to affect cultured gilthead seabream (Sparus aurata) in Southern Atlantic and Mediterranean aquaculture. Its etiological agent is the Lymphocystis disease virus (LCDV), a member of the family Iridoviridae (genus Lymphocystivirus). The only adequate measures for LCD prevention in the aquaculture systems are general prophylactic practices, such as the control of fish to be introduced in the farm facilities in order to detect carrier fish. These animals may pose a risk for the introduction of LCDV in fish farms, as direct contact between fish specimens is considered the main route of LCDV spreading. More recently, asymptomatic carrier breeders, as well as virus contaminated-live food, have been involved in LCDV transmission to fish larvae. The detection of subclinical viral infections in carrier fish requires the use of sensitive diagnostic methods. In this context, the objective of this study was to establish the applicability of a real-time PCR assay for LCDV diagnosis in surveillance studies. In addition, the assay has been evaluated with samples from a gilthead seabream hatchery, in order to prove its utility to trace the origin of LCDV in fish farms. Juvenile fish were collected at four farms with different background regarding to LCD. LCDV was detected in all farms, and 30 to 100% of fish were identified as LCDV-infected. Estimated viral load in caudal fin of asymptomatic fish was two to five orders of magnitude lower than in diseased fish. Carrier fish were also identified in the broodstock from a farm with LCD records by analysing caudal fin samples by qPCR. In this farm, the q-PCR assay developed in this study allowed the quantitative detection of LCDV in all samples collected in the hatchery, including fertilized eggs, larvae and fingerlings, and also rotifer cultures and artemia metanauplii and cysts used for larval rearing.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Genetic Characterization of a Pigeon Paramyxovirus Type 1 Isolated from Columba livia in Uruguay

The isolation and molecular characterization of pigeon paramyxovirus type 1 (PPMV-1) from a sick racing pigeon in Uruguay is reported for the first time. Hemagglutination inhibition (HI) tests were performed to detect antibodies against avian paramyxovirus serotype 1 (APMV-1), and a HI titer of 1/32 was obtained. Tracheal and cloacal swabs were processed by real-time reverse transcriptionpolymerase chain reaction (rRT-PCR) with the use of the National Veterinary Services LaboratoryU.S. Department of Agriculture validated matrix (M) gene assay and were positive for APMV-1. Viral isolation in embryonated chicken eggs confirmed the molecular detection of the isolate. A fragment corresponding to the 3' region of the fusion (F) protein gene was amplified by RT-PCR, and subsequently sequenced. The deduced amino acid sequence at the F protein cleavage site displayed the motif 112RRQKR/F 117. Phylogenetic analysis of this part of the genome allowed the isolated virus to be grouped in the lineage VIb/4b, which suggests that it shares the same ecologic niche with other PPMV-1 that were found in the region, and it is not imported as other European or North American viruses.Fil: Castro, E. R.. No especifíca;Fil: Zanetti, Flavia Adriana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Arbiza, Juan. Universidad de la Republica; Urugua

Lesiones de la articulación tarso-metatarsiana

Se presentan 16 casos de fractura-luxación tarso-metatarsiana. El objetivo de este trabajo ha sido la valoración de los resultados finales en este tipo de patología. La etiología del accidente ha sido en 6 ocasiones casual o deportiva, en 5 laboral, en 4 accidente de tráfico y 1 caída de un caballo. Las fractura-luxaciones han sido clasificadas según los criterios de Hardcastle, resultando 3 casos tipo A externo, 6 B externo, 6 B interno y 1 C total. El tratamiento realizado fue mayoritariamente reducción y osteosíntesis con agujas de Kirschner, predominando la reducción abierta. Se ha considerado parámetros radiográficos y clínicos, siguiendo los criterios del Baltimore Painful Foot Store para la valoración de resultados finales, obteniéndose 9 casos excelentes, 4 buenos, 2 reguladores y 1 malo. Se concluye que es fundamental el diagnóstico y tratamiento precoz, considerando básica la reducción anatómica estabilizada con agujas de Kirschner.We report 16 cases of tarsometatarsal fracture-dislocation. The purpose of this work was the assessment of the final outcome of these cases. The etiology was casual or sport injuries in 6 cases, industrial accidents in 5, traffic accidents in 4 and fall off a horse in 1 case. The injuries have been classified according to the Hasrdcastle modified classification, being 3 cases type A external, 6 B internqal and 1 C total. In most cases the treatment was open reduction and internal fixation with Kirschner wires. According to the guidelines of the Balitmore Painful Score for the evaluation of final outcome, there were 9 excellent results, 4 good, 2 fair and 1 poor. We conclude that the best results were obtained in those cases with early diagnose and treatment, looking for an anatomical reduction and fixation with Kirschner wires

An onto-semiotic approach to the normative dimension in mathematics education

Las nociones de contrato didáctico, norma social y sociomatemática son claves en distintas teorías didácticas, siendo diversa su conceptualización y ámbito de aplicación. En este trabajo teórico, después de hacer una síntesis de los variados modos de entender el contrato didáctico y las normas en didáctica de las matemáticas, presentamos una perspectiva que integra estas nociones como parte de una «dimensión normativa de los procesos de estudio». La consideración de esta perspectiva, desde un enfoque ontosemiótico, da lugar a una categorización de las normas según la faceta de los procesos de estudio a la que se refieren las normas: epistémica, cognitiva, interaccional, mediacional, afectiva y ecológica. Finalmente, mostramos cómo la aplicación de los criterios de idoneidad didáctica de un proceso de estudio se integran junto a las normas matemáticas, sociales y sociomatemáticas en la dimensión normativa, incorporando una racionalidad axiológica en el análisis didácticoThe concepts of didactical contract, social norms and socio-mathematical norms are very relevant in mathematics education, where they are conceptualized and applied in different ways and settings. In this article, we present a synthesis of various perspectives of norms and didactical contract as well as an onto-semiotic approach to these notions in order to include them as part of the «normative dimension» of teaching and learning processes. Using this approach we categorize the norms according the facet the norm refer to: epistemic, cognitive, interactional, meditational, affective and ecological. Finally, we apply the didactical suitability criteria to provide an axiological rationality to the didactical analysi

Identificación y especularidad en los espectadores de violencia en televisión: una reconstrucción a partir del discurso.

Numerosos autores han vinculado la experiencia de ver violencia en televisión con procesos de identificación. La investigación ha descubierto dimensiones que no recogen con precisión la experiencia peculiar de los espectadores. El objetivo de este trabajo es reconstruir la noción de identificación a partir del discurso. Se analizaron ocho grupos focales con visionado de fragmentos de programas con violencia real o ficticia. Los resultados muestran que la identificación está conectada a la especularidad, la posibilidad de experimentar la misma emoción e impacto de los personajes, según la similitud o preferencia de los espectadores. Por último, se discuten las implicaciones sobre los efectos de la violencia en televisió

Estimation of Aneurysm Wall Motion from 4D Computerized Tomographic Angiography Images

It is widely accepted that wall shear stressis associated to aneurysm formation, growthand rupture. Early identification of potential risk factors may contribute to decide the treatment and improve patient care. Previous studies have shown associations between high aneurysm wall shear stress values and both elevated risk of rupture and localization of regions of aneurysm progression. Based on the assumption that damaged regions of the endothelium have different mechanical properties, regions with differentiated wall displacement amplitudes are expected. A previous approach based on the analysis ofbidimensional dynamic tomographic angiography images at a limited number of points during the cardiac cycle showed only small displacements in some patients using that simplified and semi-automatic low resolution methodology. The purpose of this work is to overcome some of those limitations. High time and spatial resolution four dimensional computerized tomographic angiography images of cerebral aneurysms were acquired and analyzed in order to identify and characterize wall motion. Images were filtered andsegmented at nineteentime points during the cardiac cycle.An average image was computed to generate the vascular model. Anunstructured mesh of tetrahedral elements was generated using an advancing front technique. A finite element blood flow simulationwas carried out under personalized pulsatile flow conditions. A fuzzy c-means clustering algorithm was used to estimate regions that exhibit wall motion within the aneurysm sac. A good correlation between localization of regions of elevated wall shear stress and regionsexhibiting wall motion was found.Fil: Castro, Marcelo Adrian. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ahumada Olivares, María C.. Universidad Favaloro; ArgentinaFil: Putman, Christopher M. . Inova Fairfax Hospital. Department of Interventional Neuroradiology; Estados UnidosFil: Cebral, Juan R.. George Mason University. Department of Computational and Data Sciences; Estados Unido

Characterization of the Adherence of Clostridium difficile Spores: The Integrity of the Outermost Layer Affects Adherence Properties of Spores of the Epidemic Strain R20291 to Components of the Intestinal Mucosa

Indexación: Web of Science.Clostridium difficile is the causative agent of the most frequently reported nosocomial diarrhea worldwide. The high incidence of recurrent infection is the main clinical challenge of C. difficile infections (CBI). Formation of C. difficile spores of the epidemic strain R20291 has been shown to be essential for recurrent infection and transmission of the disease in a mouse model. However, the underlying mechanisms of how these spores persist in the colonic environment remains unclear. In this work, we characterized the adherence properties of epidemic R20291 spores to components of the intestinal mucosa, and we assessed the role of the exosporium integrity in the adherence properties by using cdeC mutant spores with a defective exosporium layer. Our results showed that spores and vegetative cells of the epidemic R20291 strain adhered at high levels to monolayers of Caco-2 cells and mucin. Transmission electron micrographs of Caco-2 cells demonstrated that the hair-like projections on the surface of R20291 spores are in close proximity with the plasma membrane and microvilli of undifferentiated and differentiated monolayers of Caco-2 cells. Competitive-binding assay in differentiated Caco-2 cells suggests that spore-adherence is mediated by specific binding sites. By using spores of a cdeC mutant we demonstrated that the integrity of the exosporium layer determines the affinity of adherence of C. difficile spores to Caco-2 cells and mucin. Binding of fibronectin and vitronectin to the spore surface was concentration-dependent, and depending on the concentration, spore-adherence to Caco-2 cells was enhanced. In the presence of an aberrantly-assembled exosporium (cdeC spores), binding of fibronectin, but not vitronectin, was increased. Notably, independent of the exosporium integrity, only a fraction of the spores had fibronectin and vitronectin molecules binding to their surface. Collectively, these results demonstrate that the integrity of the exosporium layer of strain R20291 contributes to selective spore adherence to components of the intestinal mucosa.http://journal.frontiersin.org/article/10.3389/fcimb.2016.00099/ful

Aproximación a la dimensión normativa en didáctica de las matemáticas desde un enfoque ontosemiótico

Las nociones de contrato didáctico, norma social y sociomatemática son claves en distintas teorías didácticas, siendo diversa su conceptualización y ámbito de aplicación. En este trabajo teórico, después de hacer una síntesis de los variados modos de entender el contrato didáctico y las normas en didáctica de las matemáticas, presentamos una perspectiva que integra estas nociones como parte de una «dimensión normativa de los procesos de estudio». La consideración de esta perspectiva, desde un enfoque ontosemiótico, da lugar a una categorización de las normas según la faceta de los procesos de estudio a la que se refieren las normas: epistémica, cognitiva, interaccional, mediacional, afectiva y ecológica. Finalmente, mostramos cómo la aplicación de los criterios de idoneidad didáctica de un proceso de estudio se integran junto a las normas matemáticas, sociales y sociomatemáticas en la dimensión normativa, incorporando una racionalidad axiológica en el análisis didáctico.The concepts of didactical contract, social norms and socio-mathematical norms are very relevant in mathematics education, where they are conceptualized and applied in different ways and settings. In this article, we present a synthesis of various perspectives of norms and didactical contract as well as an onto-semiotic approach to these notions in order to include them as part of the «normative dimension» of teaching and learning processes. Using this approach we categorize the norms according the facet the norm refer to: epistemic, cognitive, interactional, meditational, affective and ecological. Finally, we apply the didactical suitability criteria to provide an axiological rationality to the didactical analysis

Hyperbolic space in the Newtonian limit: The cosmological constant

[EN] In this paper, the cosmological constant and the Boltzmann entropy of a Newtonian Universe filled with a perfect fluid are computed, under the assumption that spatial sections are copies of 3-dimensional hyperbolic space.This research was supported by Grant No. RTI2018-102256-B-I00 (Spain).Castro-Palacio, JC.; Fernández De Córdoba, P.; Gallego Torromé, R.; Isidro, J. (2022). Hyperbolic space in the Newtonian limit: The cosmological constant. International Journal of Modern Physics D. 31(09):2250072-1-2250072-11. https://doi.org/10.1142/S02182718225007292250072-12250072-11310

Revisiting the genus Photobacterium: taxonomy, ecology and pathogenesis

The genus Photobacterium, one of the eight genera included in the family Vibrionaceae, contains 27 species with valid names and it has received attention because of the bioluminescence and pathogenesis mechanisms that some of its species exhibit. However, the taxonomy and phylogeny of this genus are not completely elucidated; for example, P. logei and P. fischeri are now considered members of the genus Aliivibrio, and previously were included in the genus Vibrio. In addition, P. damselae subsp. piscicida was formed as a new combination for former Vibrio damsela and Pasteurella piscicida. Moreover, P. damselae subsp. damselae is an earlier heterotypic synonym of P. histaminum. To avoid these incovenences draft and complete genomic sequences of members of Photobacterium are increasingly becoming available and their use is now routine for many research laboratories to address diverse goals: species delineation with overall genomic indexes, phylogenetic analyses, comparative genomics, and phenotypic inference. The habitats and isolation source of the Photobacterium species include seawater, sea sediments, saline lake waters, and a variety of marine organisms with which the photobacteria establish different relationships, from symbiosis to pathogenic interactions. Several species of this genus contain bioluminescent strains in symbiosis with marine fish and cephalopods; in addition, other species enhance its growth at pressures above 1 atmosphere, by means of several high-pressure adaptation mechanisms and for this, they may be considered as piezophilic (former barophilic) bacteria. Until now, only P. jeanii, P. rosenbergii, P. sanctipauli, and the two subspecies of P. damselae have been reported as responsible agents of several pathologies on animal hosts, such as corals, sponges, fish and homeothermic animals. In this review we have revised and updated the taxonomy, ecology and pathogenicity of several members of this genus. [Int Microbiol 20(1): 1-10 (2017)]Keywords: Photobacterium · taxonomy · symbiosis · pathogenesis · virulence factor