174 research outputs found

    The N-fixing legume Periandra mediterranea constrains the invasion of an exotic grass (Melinis minutiflora P. Beauv) by altering soil N cycling

    Get PDF
    Melinis minutiflora is an invasive species that threatens the biodiversity of the endemic vegetation of the campo rupestre biome in Brazil, displacing the native vegetation and favouring fire spread. As M. minutiflora invasion has been associated with a high nitrogen (N) demand, we assessed changes in N cycle under four treatments: two treatments with contrasting invasion levels (above and below 50%) and two un-invaded control treatments with native vegetation, in the presence or absence of the leguminous species Periandra mediterranea. This latter species was considered to be the main N source in this site due to its ability to fix N2 in association with Bradyrhizobia species. Soil proteolytic activity was high in treatments with P. mediterranea and in those severely invaded, but not in the first steps of invasion. While ammonium was the N-chemical species dominant in plots with native species, including P.mediterranea, soil nitrate prevailed only in fully invaded plots due to the stimulation of the nitrifying bacterial (AOB) and archaeal (AOA) populations carrying the amoA gene. However, in the presence of P. mediterranea, either in the beginning of the invasion or in uninvaded plots, we observed an inhibition of the nitrifying microbial populations and nitrate formation, suggesting that this is a biotic resistance strategy elicited by P. mediterranea to compete with M. minutiflora. Therefore, the inhibition of proteolytic activity and the nitrification process were the strategies elicited by P.mediterranea to constrain M.munitiflora invasion

    Is basal ultrasensitive measurement of calcitonin capable of substituting for the pentagastrin-stimulation test?

    Get PDF
    OBJECTIVE: To evaluate a second-generation assay for basal serum calcitonin (CT) measurements compared with the pentagastrin-stimulation test for the diagnosis of inherited medullary thyroid carcinoma (MTC) and the follow-up of patients with MTC after surgery. Recent American Thyroid Association recommendations suggest the use of basal CT alone to diagnose and assess follow-up of MTC as the pentagastrin (Pg) test is unavailable in many countries. DESIGN: Multicentric prospective study. PATIENTS: A total of 162 patients with basal CT <10 ng/l were included: 54 asymptomatic patients harboured noncysteine \u27rearranged during transfection\u27 (RET) proto-oncogene mutations and 108 patients had entered follow-up of MTC after surgery. MEASUREMENT: All patients underwent basal and Pg-stimulated CT measurements using a second-generation assay with 5-ng/l functional sensitivity. RESULTS: Ninety-five per cent of patients with basal CT ≥ 5 ng/l and 25% of patients with basal CT <5 ng/l had a positive Pg-stimulation test (Pg CT >10 ng/l). Compared with the reference Pg test, basal CT ≥ 5 ng/l had 99% specificity, a 95%-positive predictive value but only 35% sensitivity (P < 0.0001). Overall, there were 31% less false-negative results using a 5-ng/l threshold for basal CT instead of the previously used 10-ng/l threshold. CONCLUSION: The ultrasensitive CT assay reduces the false-negative rate of basal CT measurements when diagnosing familial MTC and in postoperative follow-up compared with previously used assays. However, its sensitivity to detect C-cell disease remains lower than that of the Pg-stimulation test

    Aplicación de diferentes metodologías en el mejoramiento de lenteja (lens culinaris medik)

    Get PDF
    La lenteja es un cultivo muy importante desde el comienzo de la revolución de la agricultura en el Viejo Mundo y uno de los primeros en ser domesticados junto al trigo, la cebada, la arveja y el lino. Se lo considera como uno de los cultivos más antiguos con unos 8000 a 9000 años de antigüedad. Desde el punto de vista nutricional posee un alto valor proteico (20-30%), alto contenido de carbohidratos (43-70%) y es una fuente rica en fibra dietética, antioxidantes, vitaminas y minerales esenciales en la dieta. En Argentina, la principal región productora se ubica al sur de Santa Fe (Departamentos de Caseros, Constitución, Rosario y San Lorenzo) y al norte de Buenos Aires (Partidos de Pergamino, Rojas y Salto). Aquí el cultivo se hace en forma extensiva, de secano y durante el invierno, y luego de la cosecha, se realiza la siembra de soja de segunda. El objetivo de este trabajo es realizar una compilación de las diferentes metodologías utilizadas en el mejoramiento de lenteja.Lentil (Lens culinaris Medik.) is a self-pollinating diploid (2n=2x=14) species belonging to the Fabaceae family. It is one of the oldest crops known, with 8,000 to 9,000 years of history and it is among the earliest domesticates from the Near East Fertile Crescent. The seeds have high nutritional value. This crop is an interesting substitute to wheat in cereal rotations but its importance is low due to a lack of suitable varieties with local adaptation. Some of the major problems that Argentinian lentil breeders face are the narrow genetic base of the current cultivated germplasm and its low yield potential. A lentil breeding program was initiated in 2004 to develop new varieties with adaptation to prevalent conditions in growing areas of Argentina. Germplasm was obtained from ICARDA (International Center for Agricultural Research in the Dry Areas) and local producers. Conventional breeding methods using hybridization and selection are being carried out to develop improved varieties, broad the genetic base, and isolate superior recombinant inbred lines. Two new varieties have been obtained, one of the macrosperm type (Boyerito FCA) and the other of the microsperm type (Tacuarita FCA) through the application of mass selection in F2 populations from the cross of selected materials. This program complements traditional breeding methods with biotechnological techniques such as transgenesis, use of molecular markers, in vitro embryo culture combined with the SSD method to shorten the breeding time, and digital phenotyping.Fil: Bermejo, Carolina Julieta. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Producción Vegetal. Cátedra de Mejoramiento Vegetal y Producción de Semillas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Maglia, F.. Ministerio de Ciencia. Tecnología e Innovación Productiva. Agencia Nacional de Promoción Científica y Tecnológica; ArgentinaFil: Palacios, T.. Ministerio de Ciencia. Tecnología e Innovación Productiva. Agencia Nacional de Promoción Científica y Tecnológica; ArgentinaFil: Espósito, María Andrea. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Producción Vegetal. Cátedra de Mejoramiento Vegetal y Producción de Semillas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Cazzola, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentina. Ministerio de Ciencia. Tecnología e Innovación Productiva. Agencia Nacional de Promoción Científica y Tecnológica; ArgentinaFil: Guindon, María Fernanda. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Producción Vegetal. Cátedra de Mejoramiento Vegetal y Producción de Semillas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; ArgentinaFil: Gatti, I.. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Producción Vegetal. Cátedra de Mejoramiento Vegetal y Producción de Semillas; ArgentinaFil: Cointry Peix, Enrique Luis. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Departamento de Producción Vegetal. Cátedra de Mejoramiento Vegetal y Producción de Semillas; Argentin

    Rhizobium Promotes Non-Legumes Growth and Quality in Several Production Steps: Towards a Biofertilization of Edible Raw Vegetables Healthy for Humans

    Get PDF
    The biofertilization of crops with plant-growth-promoting microorganisms is currently considered as a healthy alternative to chemical fertilization. However, only microorganisms safe for humans can be used as biofertilizers, particularly in vegetables that are raw consumed, in order to avoid sanitary problems derived from the presence of pathogenic bacteria in the final products. In the present work we showed that Rhizobium strains colonize the roots of tomato and pepper plants promoting their growth in different production stages increasing yield and quality of seedlings and fruits. Our results confirmed those obtained in cereals and alimentary oil producing plants extending the number of non-legumes susceptible to be biofertilized with rhizobia to those whose fruits are raw consumed. This is a relevant conclusion since safety of rhizobia for human health has been demonstrated after several decades of legume inoculation ensuring that they are optimal bacteria for biofertilization

    Cardiovascular testing recovery in Latin America one year into the COVID-19 pandemic: An analysis of data from an international longitudinal survey.

    Get PDF
    The INCAPS COVID Investigators Group, listed by name in the Appendix, thank cardiology and imaging professional societies worldwide for their assistance in disseminating the survey to their memberships. These include alphabetically, but are not limited to, American Society of Nuclear Cardiology, Arab Society of Nuclear Medicine, Australasian Association of Nuclear Medicine Specialists, Australia-New Zealand Society of Nuclear Medicine, Belgian Society of Nuclear Medicine, Brazilian Nuclear Medicine Society, British Society of Cardiovascular Imaging, Conjoint Committee for the Recognition of Training in CT Coronary Angiography Australia and New Zealand, Consortium of Universities and Institutions in Japan, Danish Society of Cardiology, Gruppo Italiano Cardiologia Nucleare, Indonesian Society of Nuclear Medicine, Japanese Society of Nuclear Cardiology, Moscow Regional Department of Russian Nuclear Medicine Society, Philippine Society of Nuclear Medicine, Russian Society of Radiology, Sociedad Española de Medicina Nuclear e Imagen Molecular, Society of Cardiovascular Computed Tomography, and Thailand Society of Nuclear Medicine.Peer reviewe

    Defining the Rhizobium leguminosarum Species Complex

    Get PDF
    Bacteria currently included in Rhizobium leguminosarum are too diverse to be considered a single species, so we can refer to this as a species complex (the Rlc). We have found 429 publicly available genome sequences that fall within the Rlc and these show that the Rlc is a distinct entity, well separated from other species in the genus. Its sister taxon is R. anhuiense. We constructed a phylogeny based on concatenated sequences of 120 universal (core) genes, and calculated pairwise average nucleotide identity (ANI) between all genomes. From these analyses, we concluded that the Rlc includes 18 distinct genospecies, plus 7 unique strains that are not placed in these genospecies. Each genospecies is separated by a distinct gap in ANI values, usually at approximately 96% ANI, implying that it is a ‘natural’ unit. Five of the genospecies include the type strains of named species: R. laguerreae, R. sophorae, R. ruizarguesonis, “R. indicum” and R. leguminosarum itself. The 16S ribosomal RNA sequence is remarkably diverse within the Rlc, but does not distinguish the genospecies. Partial sequences of housekeeping genes, which have frequently been used to characterize isolate collections, can mostly be assigned unambiguously to a genospecies, but alleles within a genospecies do not always form a clade, so single genes are not a reliable guide to the true phylogeny of the strains. We conclude that access to a large number of genome sequences is a powerful tool for characterizing the diversity of bacteria, and that taxonomic conclusions should be based on all available genome sequences, not just those of type strains

    Defining the Rhizobium leguminosarum Species Complex

    Get PDF
    Bacteria currently included in Rhizobium leguminosarum are too diverse to be considered a single species, so we can refer to this as a species complex (the Rlc). We have found 429 publicly available genome sequences that fall within the Rlc and these show that the Rlc is a distinct entity, well separated from other species in the genus. Its sister taxon is R. anhuiense. We constructed a phylogeny based on concatenated sequences of 120 universal (core) genes, and calculated pairwise average nucleotide identity (ANI) between all genomes. From these analyses, we concluded that the Rlc includes 18 distinct genospecies, plus 7 unique strains that are not placed in these genospecies. Each genospecies is separated by a distinct gap in ANI values, usually at approximately 96% ANI, implying that it is a ‘natural’ unit. Five of the genospecies include the type strains of named species: R. laguerreae, R. sophorae, R. ruizarguesonis, “R. indicum” and R. leguminosarum itself. The 16S ribosomal RNA sequence is remarkably diverse within the Rlc, but does not distinguish the genospecies. Partial sequences of housekeeping genes, which have frequently been used to characterize isolate collections, can mostly be assigned unambiguously to a genospecies, but alleles within a genospecies do not always form a clade, so single genes are not a reliable guide to the true phylogeny of the strains. We conclude that access to a large number of genome sequences is a powerful tool for characterizing the diversity of bacteria, and that taxonomic conclusions should be based on all available genome sequences, not just those of type strains

    Genetic Approach for the Fast Discovery of Phenazine Producing Bacteria

    Get PDF
    A fast and efficient approach was established to identify bacteria possessing the potential to biosynthesize phenazines, which are of special interest regarding their antimicrobial activities. Sequences of phzE genes, which are part of the phenazine biosynthetic pathway, were used to design one universal primer system and to analyze the ability of bacteria to produce phenazine. Diverse bacteria from different marine habitats and belonging to six major phylogenetic lines were investigated. Bacteria exhibiting phzE gene fragments affiliated to Firmicutes, Alpha- and Gammaproteobacteria, and Actinobacteria. Thus, these are the first primers for amplifying gene fragments from Firmicutes and Alphaproteobacteria. The genetic potential for phenazine production was shown for four type strains belonging to the genera Streptomyces and Pseudomonas as well as for 13 environmental isolates from marine habitats. For the first time, the genetic ability of phenazine biosynthesis was verified by analyzing the metabolite pattern of all PCR-positive strains via HPLC-UV/MS. Phenazine production was demonstrated for the type strains known to produce endophenazines, 2-hydroxy-phenazine, phenazine-1-carboxylic acid, phenazine-1,6-dicarboxylic acid, and chlororaphin as well as for members of marine Actinobacteria. Interestingly, a number of unidentified phenazines possibly represent new phenazine structures

    Cold-adapted RTX lipase from antarctic Pseudomonas sp. strain AMS8: isolation, molecular modeling and heterologous expression

    Get PDF
    A new strain of psychrophilic bacteria (designated strain AMS8) from Antarctic soil was screened for extracellular lipolytic activity and further analyzed using molecular approach. Analysis of 16S rDNA showed that strain AMS8 was similar to Pseudomonas sp. A lipase gene named lipAMS8 was successfully isolated from strain AMS8, cloned, sequenced and overexpressed in Escherichia coli. Sequence analysis revealed that lipAMS8 consist of 1,431 bp nucleotides that encoded a polypeptide consisting of 476 amino acids. It lacked an N-terminal signal peptide and contained a glycine- and aspartate-rich nonapeptide sequence at the C-terminus, which are known to be the characteristics of repeats-in-toxin bacterial lipases. Furthermore, the substrate binding site of lipAMS8 was identified as S207, D 255 and H313, based on homology modeling and multiple sequence alignment. Crude lipase exhibited maximum activity at 20 C and retained almost 50 % of its activity at 10 C. The molecular weight of lipAMS8 was estimated to be 50 kDa via sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The optimal expression level was attained using the recombinant plasmid pET32b/BL21(DE3) expressed at 15 C for 8 h, induced by 0.1 mM isopropyl β-D thiogalactoside (IPTG) at E. coli growth optimal density of 0.5

    Citizen seismology helps decipher the 2021 Haiti earthquake

    Get PDF
    5 pages, 4 figures, supplementary materials https://doi.org/10.1126/science.abn1045.-- Data and materials availability: All data and code used in this study are openly available. RADAR data can be obtained through ESA (Sentinel) or JAXA (Alos-2). Aftershock data can be obtained from https://ayiti.unice.fr/ayiti-seismes/ (7). The codes used to process or model the data are published and public (8). The catalog of high-precision earthquake relocated with the NLL-SSST-coherence procedure (SM4) is available as supplementary dataOn 14 August 2021, the moment magnitude (Mw) 7.2 Nippes earthquake in Haiti occurred within the same fault zone as its devastating 2010 Mw 7.0 predecessor, but struck the country when field access was limited by insecurity and conventional seismometers from the national network were inoperative. A network of citizen seismometers installed in 2019 provided near-field data critical to rapidly understand the mechanism of the mainshock and monitor its aftershock sequence. Their real-time data defined two aftershock clusters that coincide with two areas of coseismic slip derived from inversions of conventional seismological and geodetic data. Machine learning applied to data from the citizen seismometer closest to the mainshock allows us to forecast aftershocks as accurately as with the network-derived catalog. This shows the utility of citizen science contributing to our understanding of a major earthquakeThis work was supported by the Centre National de la Recherche Scientifique (CNRS) and the Institut de Recherche pour le Développement (IRD) through their “Natural Hazard” program (E.C., S.S., T.M., B.D., F.C., J.P.A., J.C., A.D., D.B., S.P.); the FEDER European Community program within the Interreg Caraïbes “PREST” project (E.C., S.S., D.B.); Institut Universitaire de France (E.C., R.J.); Université Côte d’Azur and the French Embassy in Haiti (S.P.); the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant no. 758210, Geo4D project to R.J. and grant no. 805256 to Z.D.); the French National Research Agency (project ANR-21-CE03-0010 “OSMOSE” to E.C. and ANR-15-IDEX-01 “UCAJEDI Investments in the Future” to Q.B.); the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant no. 949221 to Q.B.); and HPC resources of IDRIS (under allocations 2020-AD011012142, 2021-AP011012536, and 2021-A0101012314 to Q.B.With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)Peer reviewe
    corecore