1,720,984 research outputs found
Diversidad de levaduras en ecosistemas de Vitis no-vinifera
Full text linkThe surface of grapes lodges a complex community of yeast species responsible for spontaneous alcoholic fermentation. The study of indigenous Saccharomyces and non-Saccharomyces yeasts during grape must fermentation constitutes a major research area in microbial enology. Although there are detailed studies on the microbiota of Vitis vinifera L. grapes, little is known about the diversity of yeast communities present in non-vinifera Vitis ecosystems (i.e., grapes and spontaneously fermenting grape musts). Potentially scientific and/or enological valuable yeast strains from these non-vinifera Vitis ecosystems might never be isolated from V. vinifera L. In this updated review, we summarize relevant aspects of the microbial studies conducted on V. non-vinifera grapes and spontaneously fermenting grape musts.Fil: Raymond Eder, María Laura. Universidad Católica de Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J.; ArgentinaFil: Rosa, Alberto Luis. Universidad Católica de Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J.; Argentin
A complex interplay of genetic and epigenetic events leads to abnormal expression of the DUX4 gene in facioscapulohumeral muscular dystrophy
Full text linkFacioscapulohumeral muscular dystrophy (FSHD), a prevalent inherited human myopathy, develops following a complex interplay of genetic and epigenetic events. FSHD1, the more frequent genetic form, is associated with: (1) deletion of an integral number of 3.3 Kb (D4Z4) repeated elements at the chromosomal region 4q35, (2) a specific 4q35 subtelomeric haplotype denominated 4qA, and (3) decreased methylation of cytosines at the 4q35-linked D4Z4 units. FSHD2 is most often caused by mutations at the SMCHD1 (Structural Maintenance of Chromosomes Hinge Domain 1) gene, on chromosome 18p11.32. FSHD2 individuals also carry the 4qA haplotype and decreased methylation of D4Z4 cytosines. Each D4Z4 unit contains a copy of the retrotransposed gene DUX4 (double homeobox containing protein 4). DUX4 gene functionality was questioned in the past because of its pseudogene-like structure, its location on repetitive telomeric DNA sequences (i.e. junk DNA), and the elusive nature of both the DUX4 transcript and the encoded protein, DUX4. It is now known that DUX4 is a nuclear-located transcription factor, which is normally expressed in germinal tissues. Aberrant DUX4 expression triggers a deregulation cascade inhibiting muscle differentiation, sensitizing cells to oxidative stress, and inducing muscle atrophy. A unifying pathogenic model for FSHD emerged with the recognition that the FSHD-permissive 4qA haplotype corresponds to a polyadenylation signal that stabilizes the DUX4 mRNA, allowing the toxic protein DUX4 to be expressed. This working hypothesis for FSHD pathogenesis highlights the intrinsic epigenetic nature of the molecular mechanism underlying FSHD as well as the pathogenic pathway connecting FSHD1 and FSHD2. Pharmacological control of either DUX4 gene expression or the activity of the DUX4 protein constitutes current potential rational therapeutic approaches to treat FSHD.Fil: Gatica, Laura Virginia. Fundación Allende; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; ArgentinaFil: Rosa, Alberto Luis. Fundación Allende; Argentina. Sanatorio Allende; Argentina. Universidad Católica de Córdoba; Argentin
Differential yeast populations in grape musts from different Vitis species in a shared terroir
Full text linkThe study of indigenous microbial communities in V. vinifera L. ecosystems constitutes a major research area in oenology. Few studies, however, consider the yeast communities present in non-vinifera Vitis ecosystems. Moreover, there are no comparative studies concerning yeast communities in V. vinifera L. and non-vinifera Vitis ecosystems in a shared terroir.Fil: Raymond Eder, María Laura. Universidad Católica de Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J.; Argentina. Universidad Católica de Córdoba; ArgentinaFil: Conti, Francisco. Universidad Católica de Córdoba; ArgentinaFil: Rosa, Alberto Luis. Universidad Católica de Córdoba; Argentina. Universidad Católica de Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J.; ArgentinaLIV Reunión Anual de la Sociedad Argentina de Investigación Bioquímica y Biología MolecularParanáArgentinaConsejo Nacional de Investigaciones Científicas y TécnicasFondo para la Investigación Científica y Tecnológic
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Growth fitness of indigenous wine yeasts in grape musts from different vitis species
Full text linkYeast communities associated with Vitis vinifera L. niches (i.e. grapes and fermenting grape musts) have been widely characterized. Less is known, however, about yeast communities present in other non-vinifera Vitis ecosystems. Moreover, there are no studies concerning eventual must-specific growth fitness of indigenous wine yeast species. In this work, we have characterized the potentialmust-specific growth fitness of ten different indigenous wine yeast species (i.e. C. azymoides, C. californica, H. uvarum, H. vineae, I. hanoiensis, M. pulcherrima, P. cecembensis, T. delbrueckii, S. bacillaris and S. cerevisiae). All the analyzed strains were isolated from spontaneously fermenting musts of V. vinifera L. (cv. Malbec) and/or V. labrusca L. (cv. Isabella) grapes harvested from vineyards in a shared terroir. Yeast identification was performed using standard ITS-rDNA RFLPs and/or microsatellite genotyping. Growth fitness of selected yeast species and strains, on Malbec and Isabella pasteurized grape must media, was studied by measuring lag phases (i.e. Lag Time) and maximum growth rates (i.e. µmax). Results showed that rare yeast species isolated from the Isabella ecosystem (i.e. P. cecembensis and I. hanoiensis) have better growth parameters when growing in Isabella grape must. The growth parameters of other wine yeast species, isolated from Malbec and Isabella ecosystems, did not show any clear associations with their musts of origin. Our findings suggest that the presence of two rare yeast species in Isabella could result from their growth advantage to this Vitis ecosystem. It is possible that yeast communities assembled in alternative grape musts result from the growth fitness of yeast species and strains to each specific Vitis species. Non-conventional Vitis ecosystems may constitute a reservoir of unique yeast strains valuable in the winemaking industryFil: Raymond Eder, María Laura. Universidad Católica de Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J.; ArgentinaFil: Rosa, Alberto Luis. Universidad Católica de Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J.; Argentin
Non-tandem repeat polymorphisms at microsatellite loci in wine yeast species
Full text linkYeast microsatellite loci consist of short tandem-repeated DNA sequences of variable length. The high mutational rate at these loci generates a remarkable repertoire of alleles, useful for strain differentiation and population genetic studies. In this work, we analyze the DNA sequences of thirteen alleles from each of ten microsatellite loci described for the yeast Starmerella bacillaris. Our results show that polymorphic variants of some informative alleles are dependent on SNPs and indels rather than on length variation at their originally defined tandem-repeated motifs. The analysis was extended to 55 previously described hypervariable microsatellite loci from a total of 26 sequenced genomes of yeast species that dominate the microbiota of spontaneously fermenting grape musts (i.e., Hanseniaspora uvarum, Saccharomyces cerevisae, Saccharomyces uvarum, and Torulaspora delbrueckii) or lead to wine spoilage (Brettanomyces bruxellensis and Meyerozyma guilliermondii). We found that allelic variants for some microsatellite loci of these yeast species are also dependent on SNPs and/or indels flanking their tandem-repeated motifs. For some loci, the number of units at their tandem repeats was found to be identical among the various characterized alleles, with allelic differences being dependent exclusively on flanking polymorphisms. Our results indicate that allele sizing of microsatellite loci using PCR, although valid for strain differentiation and population genetic studies, does not necessarily score the number of units at their tandem-repeated motifs. Sequence analysis of microsatellite loci alleles could provide relevant information for evolutionary and phylogeny studies of yeast species.Fil: Raymond Eder, María Laura. Universidad Católica de Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J.; ArgentinaFil: Rosa, Alberto Luis. Universidad Católica de Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Recursos Naturales y Sustentabilidad José Sanchez Labrador S. J.; Argentin
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Pantothenate kinase-associated neurodegeneration: Novel mutations in the PANK2 gene in an Argentinean young woman
Full text linkNeurodegeneration with brain iron accumulation (NBIA) refers to a heterogeneous group of disorders.1–3 The pantothenate kinase-associated neurodegeneration (PKAN) is an autosomal recessive disorder caused by defective iron metabolism associated with mutations in the pantothenate kinase 2 (PANK2) gene on chromosome 20p13–p12.3.Fil: Gatto, Emilia Mabel. Instituto de Neurociencias Buenos Aires; ArgentinaFil: Etcheverry, Jose L.. Instituto de Neurociencias Buenos Aires; ArgentinaFil: Converso, Daniela Paola. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín. Laboratorio de Metabolismo del Oxígeno; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bidinost, Carla. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín. Laboratorio de Metabolismo del Oxígeno; ArgentinaFil: Rosa, Alberto Luis. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín. Laboratorio de Metabolismo del Oxígeno; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentin
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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