187 research outputs found

    Decreased reactive oxygen species concentration in the elongation zone contributes to the reduction in maize leaf growth under salinity

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    Reactive oxygen species (ROS) in the apoplast of cells in the growing zone of grass leaves are required for elongation growth. This work evaluates whether salinity‐induced reductions in leaf elongation are related to altered ROS production. Studies were performed in actively growing segments (SEZ) obtained from leaf three of 14‐d‐old maize (Zea mays L.) seedlings gradually salinized to 150 mM NaCl. Salinity reduced elongation rates and the length of the leaf growth zone. When SEZ obtained from the elongation zone of salinized plants (SEZs) were incubated in 100 mM NaCl, the concentration where growth inhibition was approximately 50%, O2•– production, measured as NBT formazan staining, was lower in these than in similar segments obtained from control plants. The NaCl effect was salt‐specific, and not osmotic, as incubation in 200 mM sorbitol did not reduce formazan staining intensity. SEZs elongation rates were higher in 200 mM sorbitol than in 100 mM NaCl, but the difference could be cancelled by scavenging or inhibiting O2•– production with 10 mM MgCl2 or 200 µM diphenylene iodonium, respectively. The actual ROS believed to stimulate growth is •OH, a product of O2•– metabolism in the apoplast. SEZs elongation in 100 mM NaCl was stimulated by a •OH‐generating medium. Fusicoccin, an ATPase stimulant, and acetate buffer pH 4, could also enhance elongation in these segments, although both failed to increase ROS activity. These results show that decreased ROS production contributes to the salinity‐associated reduction in grass leaf elongation, acting through a mechanism not associated with pH changes.Instituto de Fisiología y Recursos Genéticos VegetalesFil: Rodriguez, Andrés Alberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales (ex IFFIVE); ArgentinaFil: Córdoba, Alicia R. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales (ex IFFIVE); ArgentinaFil: Ortega, Leandro Ismael. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales (ex IFFIVE); ArgentinaFil: Taleisnik, Edith. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales (ex IFFIVE); Argentin

    Quantitative real-time PCR method with internal amplification control to quantify cyclopiazonic acid producing molds in foods

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    A quantitative TaqMan real-time PCR (qPCR) method that includes an internal amplification control (IAC) to quantify cyclopiazonic acid (CPA)-producing molds in foods has been developed. A specific primer pair (dmaTF/dmaTR) and a TaqMan probe (dmaTp) were designed on the basis of dmaT gene which encodes the enzyme dimethylallyl tryptophan synthase involved in the biosynthesis of CPA. The IAC consisted of a 105 bp chimeric DNA fragment containing a region of the hly gene of Listeria monocytogenes. Thirty-two mold reference strains representing CPA producers and non-producers of different mold species were used in this study. All strains were tested for CPA production by high-performance liquid chromatography-mass spectrometry (HPLC-MS). The functionality of the designed qPCR method was demonstrated by the high linear relationship of the standard curves relating to the dmaT gene copy numbers and the Ct values obtained from the different CPA producers tested. The ability of the qPCR protocol to quantify CPA-producing molds was evaluated in different artificially inoculated foods. A good linear correlation was obtained over the range 1-4 log cfu/g in the different food matrices. The detection limit in all inoculated foods ranged from 1 to 2 log cfu/g. This qPCR protocol including an IAC showed good efficiency to quantify CPA-producing molds in naturally contaminated foods avoiding false negative results. This method could be used to monitor the CPA producers in the HACCP programs to prevent the risk of CPA formation throughout the food chain.Fil: Rodríguez, Alicia. Universidad de Extremadura. Facultad de Veterinaria; EspañaFil: Werning, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rodríguez, Mar. Universidad de Extremadura. Facultad de Veterinaria; EspañaFil: Bermúdez, Elena. Universidad de Extremadura. Facultad de Veterinaria; EspañaFil: Córdoba, Juan J.. Universidad de Extremadura. Facultad de Veterinaria; Españ

    Laboratorización del mundo. Escenarios contemporáneos de la ciencia y la tecnología

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    Introducción al dossier del número seis.  

    From the laboratory to the field: trajectory of the researcher who managed to clone the best Polo horses in Argentina

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    El trabajo pone en juego una entrevista de trayectoria profesional de un reconocido investigador del campo de la biotecnología animal en Argentina, con el objetivo de desplegar su itinerario, reponer los dilemas que enfrentó y los modos en que resolvió las encrucijadas a las que se vio confrontado. En este recorrido, quedan expuestos los enormes desafíos éticos, sociales y políticos que plantea la modificación (por transgénesis o por edición genética) de organismos vivos, así como el debate aún vigente sobre el estatus de mercancía adquirido por el conocimiento científico mediante el proceso de patentamiento de dichas “invenciones”. Aspectos que constituyen una fuente de interrogación para la antropología que se interesa en el rol que tienen la ciencia y la tecnología en las sociedades contemporáneas.This work puts forward a professional career interview with a renowned researcher in the field of animal biotechnology in Argentina. The aim is to deploy his work itinerary, present the dilemmas he faced and the ways in which he resolved them. In this journey, the enormous ethical, social and political challenges posed by the modification (by transgenesis or by genetic editing) of living organisms are exposed, as well as the debate around the status of merchandise that scientific knowledge has achieved through the process of patenting of so called "inventions". All this aspects constitute a source of inquire for anthropology that’s seeks to explore the role of science and technology in contemporary societies.Fil: Hernandez, Valeria Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto de Altos Estudios Sociales; ArgentinaFil: Córdoba, María Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto de Altos Estudios Sociales; Argentin

    Le rôle de la diaspora circulaire dans le développement du secteur biotechnologique argentin

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    Cet article traite de la mobilité internationale de scientifiques argentins dont le travail s’inscrit dans le secteur de la biologie moléculaire et des biotechnologies1 . Il a été élaboré à partir d’un travail de recherche réalisé entre octobre 2009 et avril 20112 , afin d’obtenir un premier cadre analytique des rapports entre le secteur biotechnologique argentin (public et privé) et les scientifiques argentins expatriés. Nous avons eu recours à des études qualitatives et quantitatives selon les nécessités du processus de compréhension en cours. En premier lieu, pour obtenir une photographie globale du secteur, nous utilisons une information disponible dans des centres de recherche et observatoires de science et technologie de la région — comme les rapports et bases de données de la plate-forme Biotecsur, du Centre Redes et du Ministère de Science, Technique et Innovation productive (MINCYT). De cette façon, nous avons constitué un listing de 90 entités3 , composé d’entreprises privées et d’instituts publics sur lequel nous avons réalisé une première caractérisation quant aux aires de spécialisation, possession de brevets et implantation d’un secteur de recherche et de développement (I&D). Nous avons obtenu finalement une liste dépurée de 50 entités que nous avons contacté pour solliciter leur collaboration à cette recherche; 40 ont accepté de répondre à une enquête auto-administrée. Finalement, nous avons obtenu 32 questionnaires complétés, univers sur lequel nous avons identifié neuf cas qui ont déclaré avoir des rapports avec a diaspora scientifique et technique (DCT): cinq entreprises argentines (Biogénesis-Bagó, Biosidus, Don Mario Semillas, Craveri et Bioprofarma), deux entités de recherches publiques (Laboratoire d’Hémodérivés de l’Université Nationale de Cordoba et le Laboratoire de Cultures Cellulaires de l’Université Nationale du Littoral) et deux instituts privés avec une forte synergie sur le système public de recherche (Fondation Institution Leloir et l’Institut d’Agro-biotechnologie de Rosario). Ces neuf cas ont fait l’objet d’un travail de caractérisation détaillée pour lequel nous avons utilisé une approche ethnographique. Nous présenterons ci-dessous, en premier lieu, le contexte argentin des biotechnologies pour faire ensuite référence aux cas d’étude, en observant les modes particuliers de relation avec la DTC. Nous conclurons par quelques réflexions sur le rôle de la diaspora comme vecteur de développement pour des pays ayant une certaine tradition scientifique et technologique comme c’est le cas de l’Argentine (et de divers pays latino-américains).Fil: Hernandez, Valeria Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Institut de Recherche Pour Le Developpement; FranciaFil: Córdoba, María Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto de Altos Estudios Sociales; Argentin

    Rescue of a genotype 4 human hepatitis E virus from cloned cDNA and characterization of intergenotypic chimeric viruses in cultured human liver cells and in pigs

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    Hepatitis E virus (HEV) is an important but extremely understudied human pathogen. Genotypes 1 and 2 are restricted to humans, whereas genotypes 3 and 4 are zoonotic, infecting both humans and pigs. This report describes, for the first time, the successful rescue of infectious HEV in vitro and in vivo from cloned cDNA of a genotype 4 human HEV (strain TW6196E). The complete genomic sequence of the TW6196E virus was determined and a full-length cDNA clone (pHEV-4TW) was assembled. Capped RNA transcripts from the pHEV-4TW clone were replication competent in Huh7 cells and infectious in HepG2/C3A cells. Pigs inoculated intrahepatically with capped RNA transcripts from pHEV-4TW developed an active infection, as evidenced by faecal virus shedding and seroconversion, indicating the successful rescue of infectious genotype 4 HEV and cross-species infection of pigs by a genotype 4 human HEV. To demonstrate the utility of the genotype 4 HEV infectious clone and to evaluate the potential viral determinant(s) for species tropism, four intergenotypic chimeric clones were constructed by swapping various genomic regions between genotypes 1 and 4, and genotypes 1 and 3. All four chimeric clones were replication competent in Huh7 cells, but only the two chimeras with sequences swapped between genotypes 1 and 4 human HEVs produced viruses capable of infecting HepG2/C3A cells. None of the four chimeras was able to establish a robust infection in pigs. The availability of a genotype 4 HEV infectious clone affords an opportunity to delineate the molecular mechanisms of HEV cross-species infection in the future

    ESTUDIO CLINICO-PATOLÓGICO DE LAS PRINCIPALES CAUSAS DE MUERTE PERINATAL

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    Introducción: La muerte u óbito fetal se define como la ausencia de latido cardiaco, pulsación del cordón, respiración espontánea y movimientos fetales.Es fundamental conocer las causas de muerte fetal intrauterina. Hay que tener en cuenta que en muchos casos la causa o los factores que contribuyen a la muerte son desconocidos.Para ello, se requiere la realización del estudio anatomopatológico del feto y de la placenta. Los datos obtenidos de este estudio junto a los antecedentes maternos clínicos o de laboratorio pueden ayudar a conocer el origen de la muerte fetal.Objetivo: Conocer las principales causas de muerte fetal perinatal, valorando los antecedentes clínicos maternos más relevantes, así como, los hallazgos patológicos encontrados tras la realización de la autopsia fetal y tras el estudio de la placenta.Material y métodos: Se realizó un estudio observacional y retrospectivo de las autopsias fetales perinatales, realizadas a partir de la semana 22 de gestación o ≥ 500 g y hasta los 28 días de vida, solicitadas al Servicio de Anatomía Patológica del Complejo Hospitalario de Navarra entre enero de 2018 y enero de 2021.Resultados: Tras el análisis de los datos, durante el periodo de enero de 2018 a enero de 2021 independientemente de la edad gestacional se solicitaron un total de 122 autopsias fetales al Servicio de Anatomía patológica del CHN. En concreto durante el periodo perinatal se solicitaron 26 autopsias. 2 de ellas no fueron incluidas en el estudio por la imposibilidad de acceso a los datos clínicos maternos, resultando un número final de 24 casos. Los factores maternos, fetales y placentarios pueden aparecer de forma aislada o tener relación entre ellos. En 11 casos (46%) se observó la presencia de un solo factor de riesgo, en 9 casos (37%) coexistían dos factores de riesgo y en un único caso (4%) se identificó correlación entre un factor materno, fetal y placentario. En 3 casos (13%) no pudieron identificarse factores de riesgo de muerte fetal.Conclusiones: El análisis de los hallazgos de la autopsia fetal, del estudio de la placenta y de los antecedentes clínicos maternos, permiten aclarar la causa de la mayoría de las muertes fetales. Además, puede ayudar en la orientación y manejo de embarazos posteriores.<br /

    Prognostic Factor Utility of BAP1 Immunohistochemistry in Uveal Melanoma: A Single Center Study in Spain

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    Even today, the mortality rate for uveal melanoma (UM) remains very high. In our research, we sought to determine which pathological and clinical features were correlated with the prognosis of UM. BAP1 (BRCA1-Associated Protein 1) gene mutation has been analyzed as one of the strongest predictors for metastasis in UM. The BAP1 gene codifies the BAP1 protein which has a tumor suppressor function. The presence of this protein can be determined by BAP1 immunohistochemical staining. Eighty-four uveal melanoma patients and forty enucleated eyeballs were examined. Metastasis was present in 24 patients. Nuclear BAP1 staining was low in 23 patients. The presence of a higher large basal diameter tumor (p < 0.001), tumor infiltrating lymphocytes (p = 0.020), and a lack of nuclear BAP1 immunostaining (p = 0.001) ocurred significantly more often in the metastatic group. Metastasis-free survival was lower in patients with low nuclear BAP1 staining (p = 0.003). In conclusion, to the best of our knowledge, this is the first time that BAP1 staining has been studied in uveal melanoma in a Spanish community. We believe that this technique should become routine in the pathological examination of uveal melanoma in order to allow adequate classification of patients and to establish an individual follow-up plan.This research was partially funded by research grants from the “Instituto de Salud Carlos III/European Regional Development Fund (ERDF)” and RD16/0008/0011, OFTARED: Enfermedades oculares: “Prevención, detección precoz, tratamiento y rehabilitación de las patologías oculares”. Publication costs are covered by “Clínica Universidad de Navarra” and “Fundación Miguel Servet”.S
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