2,019 research outputs found

    Incidence of Grapevine Leafroll Associated Viruses -1, -2, and -3 in Mendoza vineyards

    Get PDF
    Viticulture is important in Argentina's economy, especially in the province of Mendoza, which is responsible for more than 75% of the crop cultivated area. In this work, we evaluated the incidence of Grapevine leafroll-associated viruses (GLRaV) -1, -2, and -3 in Vitis vinifera clones of cultivars Cabernet Sauvignon, Cabernet Franc, and Sauvignon Blanc, planted in different zones of Mendoza. The selected clones were previously reported as putatively infected by GLRaV-2. All selected samples were analyzed by DAS-ELISA for GLRaV-1,-2 and -3. GLRaV-2 was the only virus identified in all the analyzed clones. The overall infection rates were 0.6%, 18.8% and 1.2 % for GLRaV-1, 2 and 3 respectively. For the clone Cabernet Sauvignon 337, the infection rate was very high (68.3%).A viticultura é importante para a economia da Argentina, especialmente na província de Mendoza, que abrange mais de 75% da área cultivada do país. Neste trabalho, nós avaliamos a incidência de Grapevine leafroll associated virus (GLRaV) -1, -2 e -3 em clones de Vitis vinifera das cultivares Cabernet Sauvignon, Cabernet Franc e Sauvignon Blanc, cultivadas em diferentes zonas de Mendoza. Os clones selecionados foram previamente relatados como provavelmente infectados por GLRaV-2. Todas as amostras selecionadas foram analisadas por DAS-ELISA para GLRaV-1, -2 e -3. GLRaV-2 foi o único vírus identificado em todos os clones analisados. As incidëncias das infecçoes globais foram 0,6%, 18,8% e 1,2% para GLRaV-1, 2 e 3, respectivamente. No Cabernet Sauvignon clone 337 a incidëncia da infecção foi muito elevado (68,3%)Fil: Lanza Volpe, Melisa. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; ArgentinaFil: Gomez Talquenca, Gonzalo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; ArgentinaFil: Engel, Esteban A. Fundación Ciencia para la Vida; Chile. Universidad Andrés Bello. Facultad de Ciencias de la Salud; ChileFil: Gracia, Olga. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; Argentin

    Detection of Replay Attacks to GNSS based on Partial Correlations and Authentication Data Unpredictability

    Full text link
    Intentional interference, and in particular GNSS spoofing, is currently one of the most significant concerns of the Positioning, Navigation and Timing (PNT) community. With the adoption of Open Service Navigation Message Authentication (OSNMA) in Galileo, the E1B signal component will continuously broadcast unpredictable cryptographic data. This allows GNSS receivers not only to ensure the authenticity of data origin but also to detect replay spoofing attacks for receivers already tracking real signals with relatively good visibility conditions. Since the spoofer needs to estimate the unpredictable bits introduced by OSNMA with almost zero delay in order to perform a Security Code Estimation and Replay (SCER) attack, the spoofer unavoidably introduces a slight distortion into the signal, which can be the basis of a spoofing detector. In this work, we propose five detectors based on partial correlations of GNSS signals obtained over predictable and unpredictable parts of the signals. We evaluate them in a wide set of test cases, including different types of receiver and spoofing conditions. The results show that one of the detectors is consistently superior to the others, and it is able to detect SCER attacks with a high probability even in favorable conditions for the spoofer. Finally, we discuss some practical considerations for implementing the proposed detector in receivers, in particular when the Galileo OSNMA message structure is used

    Aspectos etiopatogénicos del asma bronquial en el niño

    Full text link

    Antigen Discovery for the Identification of Vaccine Candidates and Biomarkers Using a T Cell Driven Approach in Combination with Positional Scanning Peptide Libraries

    Get PDF
    The prevention and treatment of infectious diseases is highly dependent on the availability of reliable diagnostic tests and protective or therapeutic vaccines. There also exists an urgent need to develop reliable biomarkers to monitor treatment success and to predict disease progression from asymptomatic to symptomatic disease in several disease scenarios. The elucidation of the disease-relevant antigens that elicit the protective immune responses is critical and required for the development of biomarkers, diagnostics, and vaccines. However; one of the main obstacles to the study of antigen specificity in human T cells is their low frequency in PBMC samples. To overcome this problem we have implemented strategies to generate memory T cell libraries and clones specific to the pathogen of interest. Due to the fact that memory T cells represent a repository of the human T cell response to infection, examination of their antigen specificity can efficiently reveal immunogenic and relevant antigens involved in the in vivo response to infection or vaccines. To examine the specificity of the memory T cells we use an unbiased collection of antigens together with an in silico analysis, namely positional scanning based biometrical analysis. Here we present a summary of our approach and ongoing work on the development of strategies for the culture of memory T cells from patients with Chagas disease. While most studies focus on the identification of vaccine candidates using preselected immunogenic proteins derived from animal models or by or bioinformatics prediction, here we present an innovative approach that directly examines the specificity of the memory response following infection or immunization in humans

    Analytical description of optical vortices generated by discretized vortex-producing lenses

    Get PDF
    In this article, a general analytical treatment (any topological charge - any number of discretization levels) for the diffraction of a Gaussian beam through a discretized vortex-producing lens is presented. In the proposal, the field is expressed as a sum of Kummer beams with different amplitudes and topological charges, which are focalized at different planes on the propagation axis. Likewise, it is demonstrated that characteristics of diffracted light can be modified by tuning the parameters of the setup. Vortex lines are analyzed to understand the internal mechanism of measurable topological charges that appear in specific planes, apparently violating topological charge conservation. Conservation of the topological charge is verified and theoretical predictions are supported by experiments.Fil: Rumi, Gonzalo Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Ópticas. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones Ópticas. Universidad Nacional de La Plata. Centro de Investigaciones Ópticas; ArgentinaFil: Actis, Daniel Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Ópticas. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones Ópticas. Universidad Nacional de La Plata. Centro de Investigaciones Ópticas; ArgentinaFil: Amaya Robayo, Dafne Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Ópticas. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones Ópticas. Universidad Nacional de La Plata. Centro de Investigaciones Ópticas; ArgentinaFil: Gomez, Jorge A.. Politécnico Colombiano Jaime Isaza Cadavid; ColombiaFil: Rueda, Edgar. Universidad de Antioquia; ColombiaFil: Lencina, Alberto Germán. Universidad Nacional del Centro de la Provincia de Buenos Aires; Argentin

    Genetic and Transcription Profile Analysis of Tissue-Specific Anthocyanin Pigmentation in Carrot Root Phloem

    Get PDF
    In purple carrots, anthocyanin pigmentation can be expressed in the entire root, or it can display tissue specific-patterns. Within the phloem, purple pigmentation can be found in the outer phloem (OP) (also called the cortex) and inner phloem (IP), or it can be confined exclusively to the OP. In this work, the genetic control underlying tissue-specific anthocyanin pigmentation in the carrot root OP and IP tissues was investigated by means of linkage mapping and transcriptome (RNA-seq) and phylogenetic analyses; followed by gene expression (RT-qPCR) evaluations in two genetic backgrounds, an F2 population (3242) and the inbred B7262. Genetic mapping of ‘root outer phloem anthocyanin pigmentation’ (ROPAP) and inner phloem pigmentation (RIPAP) revealed colocalization of ROPAP with the P1 and P3 genomic regions previously known to condition pigmentation in different genetic stocks, whereas RIPAP co-localized with P3 only. Transcriptome analysis of purple OP (POP) vs. non-purple IP (NPIP) tissues, along with linkage and phylogenetic data, allowed an initial identification of 28 candidate genes, 19 of which were further evaluated by RT-qPCR in independent root samples of 3242 and B7262, revealing 15 genes consistently upregulated in the POP in both genetic backgrounds, and two genes upregulated in the POP in specific backgrounds. These include seven transcription factors, seven anthocyanin structural genes, and two genes involved in cellular transport. Altogether, our results point at DcMYB7, DcMYB113, and a MADS-box (DCAR_010757) as the main candidate genes conditioning ROPAP in 3242, whereas DcMYB7 and MADS-box condition RIPAP in this background. In 7262, DcMYB113 conditions ROPAP.EEA MendozaFil: Bannoud, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Carvajal, Sofía. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ellison, Shelby. University of Wisconsin. Department of Horticulture; Estados Unidos.Fil: Senalik, Douglas A. United States Department of Agriculture–Agricultural Research Service. Vegetable Crops Research Unit; Estados UnidosFil: Gomez Talquenca, Gonzalo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; ArgentinaFil: Iorizzo, Massimo. North Carolina State University. Plants for Human Health Institute; Estados UnidosFil: Iorizzo, Massimo. North Carolina State University. Department of Horticultural Science; Estados UnidosFil: Simon, Philipp. University of Wisconsin. Department of Horticulture; Estados Unidos.Fil: Simon, Philipp. United States Department of Agriculture–Agricultural Research Service. Vegetable Crops Research Unit; Estados UnidosFil: Cavagnaro, Pablo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria La Consulta; ArgentinaFil: Cavagnaro, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cavagnaro, Pablo. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Horticultura; Argentina

    Methodological approach to the ex vivo expansion and detection of T. cruzi-specific T cells from chronic Chagas disease patients

    Get PDF
    The discovery of T cell epitopes is essential not only for gaining knowledge about host response to infectious disease but also for the development of immune-intervention strategies. In Chagas disease, given the size and complexity of the Trypanosoma cruzi proteome and its interaction with the host’s immune system, the fine specificity of T cells has not been extensively studied yet, and this is particularly true for the CD4+ T cell compartment. The aim of the present work was to optimize a protocol for the generation of parasite-specific memory T cell lines, representative of their in vivo precursor populations and capable of responding to parasite antigens after long-term culture. Accordingly, peripheral blood mononuclear cells (PBMC) from both chronic asymptomatic and cardiac patients, and from non-infected individuals, underwent different in vitro culture and stimulation conditions. Subsequently, cells were tested for their capacity to respond against T. cruzi lysate by measuring [3H]-thymidine incorporation and interferon-γ and GM-CSF secretion. Results allowed us to adjust initial T. cruzi lysate incubation time as well as the number of expansions with phytohemagglutinin (PHA) and irradiated allogeneic PBMC prior to specificity evaluation. Moreover, our data demonstrated that parasite specific T cells displayed a clear and strong activation by using T. cruzi lysate pulsed, Epstein-Barr virus (EBV)-transformed human B lymphocytes (B-LCL), as autologous antigen presenting cells. Under these culture conditions, we generated a clone from an asymptomatic patient’s memory CD4+ T cells which responded against epimastigote and trypomastigote protein lysate. Our results describe a culture method for isolating T. cruzispecific T cell clones from patients with Chagas disease, which enable the acquisition of information on functionality and specificity of individual T cells

    Independent genomic polymorphisms in the PknH serine threonine kinase locus during evolution of the Mycobacterium tuberculosis Complex affect virulence and host preference

    Get PDF
    Species belonging to the Mycobacterium tuberculosis Complex (MTBC) show more than 99% genetic identity but exhibit distinct host preference and virulence. The molecular genetic changes that underly host specificity and infection phenotype within MTBC members have not been fully elucidated. Here, we analysed RD900 genomic region across MTBC members using whole genome sequences from 60 different MTBC strains so as to determine its role in the context of MTBC evolutionary history. The RD900 region comprises two homologous genes, pknH1 and pknH2, encoding a serine/threonine protein kinase PknH flanking the tbd2 gene. Our analysis revealed that RD900 has been independently lost in different MTBC lineages and different strains, resulting in the generation of a single pknH gene. Importantly, all the analysed M. bovis and M. caprae strains carry a conserved deletion within a proline rich-region of pknH, independent of the presence or absence of RD900. We hypothesized that deletion of pknH proline rich-region in M. bovis may affect PknH function, having a potential role in its virulence and evolutionary adaptation. To explore this hypothesis, we constructed two M. bovis ‘knock-in’ strains containing the M. tuberculosis pknH gene. Evaluation of their virulence phenotype in mice revealed a reduced virulence of both M. bovis knock-in strains compared to the wild type, suggesting that PknH plays an important role in the differential virulence phenotype of M. bovis vs M. tuberculosis
    • …
    corecore