1,278 research outputs found

    Quantitative phylogenomic evidence reveals a spatially structured SARS-CoV-2 diversity

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    Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emergent RNA virus that spread around the planet in about 4 months. The consequences of this rapid dispersion are under investigation. In this work, we analyzed thousands of genomes and protein sequences from Africa, America, Asia, Europe, and Oceania. We provide statistically significant evidence that SARS-CoV-2 phylogeny is spatially structured. Remarkably, the virus phylogeographic patterns were correlated with ancestral amino acidic substitutions, suggesting that such mutations emerged along colonization events. We hypothesize that geographic structuring is the result of founder effects occurring as a consequence of, and local evolution occurring after, long-distance dispersion. Based on previous studies, the possibility that this could significantly affect the virus biology is not remote.Fil: Jones, Leandro Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales y Ciencias de la Salud - Sede Trelew. Laboratorio de Virología y Genética Molecular; ArgentinaFil: Manrique, Julieta Marina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales y Ciencias de la Salud - Sede Trelew. Laboratorio de Virología y Genética Molecular; Argentin

    Evidence for the existence of pathogenicity determinants in the Long Terminal Repeats (LTRs) of the Bovine Leukemia Virus (BLV) genome

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    peer reviewedaudience: researcherEvidence for the existence of pathogenicity determinants in the Long Terminal Repeats (LTRs) of the Bovine Leukemia Virus (BLV) genome Sabrina M. Rodríguez1*, Karina Trono2, Leandro R. Jones3 1 Molecular and Cellular Epigenetics, Interdisciplinary Cluster for Applied Genoproteomics (GIGA) , University of Liège (ULg), Belgium. 2 Instituto de Virología, CICVyA, Instituto Nacional de Tecnología Agropecuaria INTA-Castelar, CC 25 (1712), Castelar. 3 División de Biología Molecular, Estación de Fotobiología Playa Unión, CC 15, Rawson, Chubut 9103, Argentina. *E-mail: [email protected] The majority of BLV-infected animals are asymptomatic carriers (AL) while about 30% develop a benign persistent lymphocytosis (PL). Fatal lymphosarcoma (LS) occurs in 5% of infected animals. The genetic basis of these diverse outcomes of BLV infection is still unknown. Viral LTRs constitute a genetic determinant of pathogenesis for other retroviruses. However, this possibility has never been tested for BLV. Analyses to test correlation between clinical and genotypic traits across species must be corrected by including the group phylogeny. Otherwise, shared evolutionary history can jeopardize statistical independence. Thus, the influence of BLV LTR genetic variation on the clinical manifestation of the disease was investigated by employing Cladistic and Probabilistic, phylogenetic comparative methods. With this purpose, the 5´LTR region of 40 BLV proviruses from bovines with different clinical presentations (AL, PL, LS) was sequenced. Seven polymorphic positions showing an apparent association with the clinical presentation were identified. A provirus phylogeny was obtained using env gene sequences from 28 of the 40 provirus studied in this work. Both Cladistic and Probabilistic comparative analyses based on the empirical sequence alignment and the provirus phylogeny suggested that positions 41 and 56 might be correlated to the clinical presentation. The probabilistic analysis further indicated an association with the viral pathogenesis for positions 373, 450, 494 and 505, though the corresponding statistical supports were lower in comparison to the supports obtained for positions 41 and 56. These observations indicate that the BLV LTRs might contain pathogenicity determinants

    Phylogenetic analysis of Ostreococcus virus sequences from the Patagonian Coast

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    A phylogenetic analysis of new Ostreococcus virus (OV) sequences from the Patagonian Coast, Argentina, and homologous sequences from public databases was performed. This analysis showed that the Patagonian sequences represented a divergent viral clade and that the rest of OV sequences analyzed here were clustered into six additional phylogenetic groups. Analyses of 18S gene libraries supported a close relationship of the Patagonian Ostreococcus host with clade A sequences described elsewhere, corroborating previous studies indicating that clade A strains are ubiquitous. Besides the Patagonian OV sequences, several phylogenetic groupings were linked to particular geographic locations, suggesting a role for allopatric cladogenesis in viral diversification. However, and in agreement with previous observations, other viral lineages included sequences with diverse geographic origins. These findings, together with analyses of ancestral trait trajectories performed here, are consistent with an evolutionary dynamics in which geographical isolation has a role in OV diversification but can be followed by rapid dispersion to remote places.Fil: Manrique, Julieta Marina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Playa Unión. Estación de Fotobiología Playa Unión; ArgentinaFil: Calvo, Andrea Yamila. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Playa Unión. Estación de Fotobiología Playa Unión; ArgentinaFil: Jones, Leandro Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Playa Unión. Estación de Fotobiología Playa Unión; Argentin

    An optimized DNA extraction protocol for benthic Didymosphenia geminata

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    Didymosphenia geminata mats display few cells in relation to extracellular material and contain polysaccharides and heavy metals that interfere with molecular studies. We describe an optimized DNA extraction protocol that help to overcome these difficulties. Our protocol outperformed five previously described DNA extraction techniques.Fil: Uyua, Noelia Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Trelew; ArgentinaFil: Manrique, Julieta Marina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Trelew; ArgentinaFil: Jones, Leandro Roberto. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Trelew; Argentin

    Biologics for treating axial spondyloarthritis

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    INTRODUCTION: Spondyloarthritis (SpA) encompasses a heterogeneous group of diseases sharing genetic, immunological, clinical and imaging features. Axial spondyloarthritis (axSpA) refers to a subgroup characterised predominately by inflammation of the axial skeleton with subsequent symptoms of chronic (often inflammatory) back pain and sacroiliitis. There is a strong association with the major histocompatibility complex (MHC) class I allele human leukocyte antigen (HLA) B27. In the last decade, there has been significant progress in earlier detection of the disease and the molecular mechanisms involved in its pathogenesis. The subsequent introduction of anti-tumour necrosis factor (TNF) has revolutionised the treatment of patients with axSpA. Areas covered: In this article, we review the current biologic therapies for axSpA, the emergence of biosimilars, predictors of response, primary and secondary failure and new biologics on the horizon. Expert opinion: There have been significant advances in the treatment of axSpA. Beyond the clear efficacy of anti-TNF inhibition, IL-17 offers an alternative therapeutic target and there is promise from inhibition of the IL-17/IL-23 pathway and small molecules, such as Janus kinase (JAK) inhibitors. Biosimilars have offered greater affordability and choice within this increasingly growing field of therapeutics

    Bovine leukemia virus can be classified into seven genotypes: evidence for the existence of two novel clades.

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    Previous studies have classified the env sequences of bovine leukemia virus (BLV) provirus from different locations worldwide into between two and four genetic groupings. These different studies gave unique names to the identified groups and no study has yet integrated all the available sequences. Thus, we hypothesized that many of the different groups previously identified actually correspond to a limited group of genotypes that are unevenly distributed worldwide. To examine this hypothesis, we sequenced the env gene from 28 BLV field strains and compared these sequences to 46 env sequences that represent all the genetic groupings already identified. By using phylogenetic analyses, we recovered six clades, or genotypes, that we have called genotypes 1, 2, 3, 4, 5 and 6. Genotypes 1-5 have counterparts among the sequence groupings identified previously. One env sequence did not cluster with any of the others and was highly divergent when compared with the six genotypes identified here. Thus, an extra genotype, which we named 7, may exist. Similarity comparisons were highly congruent with phylogenetic analyses. Furthermore, our analyses confirmed the existence of geographical clusters

    Inter and intra-host variability of hepatitis C virus genotype 1a hypervariable envelope coding domains followed for a 4-11 year of human immunodeficiency virus coinfection and highly active antiretroviral therapy

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    The evolution of hepatitis C virus (HCV) quasispecies in patients with HIV-1 coinfection is not fully understood. The HCV-1a quasispecies heterogeneity was analyzed at inter and intra-host levels along 7.6 years in 21 coinfected patients that showed different virological and immunological responses to highly active antiretroviral therapy (HAART). Two to nine serial samples were subjected to direct and clonal sequence analyses of the envelope glycoprotein 2 (E2) gene. E2-based phylogenies, intra-host HCV evolution and evolutionary rates, as well as dynamics of the quasispecies heterogeneity parameters were evaluated. Bayesian coalescent phylogenies indicated complex evolutionary histories, revealing some viral lineages that persisted along the follow up and others that were detectable at a single or some sampling times, suggesting the occurrence of emergence-extinction cycles. HCV quasispecies underwent very rapid evolution in HAART-treated patients (~3.1 × 10(-2) sub/site/year) following the recovery of the host immunocompetence irrespectively of the virological response to HAART.Fil: Sede, Mariano Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; ArgentinaFil: Jones, Leandro Roberto. Universidad Nacional de la Patagonia ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Moretti, Franco. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; ArgentinaFil: Laufer, Natalia Lorna. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; ArgentinaFil: Quarleri, Jorge Fabian. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentin

    Linear polyethylenimine-decorated gold nanoparticles: One-step electrodeposition and studies of interaction with viral and animal proteins

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    Polyethylenimine (PEI)-decorated gold nanoparticles (AuNP) were electrodeposited on conductive surfaces in one-step procedure. Solution-state NMR evidenced that chloride from PEI.HCl was partially exchanged by AuCl 4 − prior to AuNP formation. XPS studies indicated the presence of Au° together with the interaction between AuNP with nitrogen atoms of the PEI polymer. The particle size by DLS was 49 nm. The electrochemical behavior of bare electrode and of glassy carbon electrode modified with PEI-decorated AuNP was compared using [Fe(CN) 6 ] 3-/4- redox probe, to determine the potential role of the nanomaterial and of the polymer in the detection of proteins. The most relevant experimental variables from cyclic voltammetry (CV), square-wave voltammetry (SWV) and electrochemical impedance spectroscopy (EIS) were used for the characterization of protein uptake. The adsorption by electrostatic interaction between the biomolecules and the positively charged polymer (PEIH + ) affected negatively the current response (Ip) of the probe, especially when the negatively charged protein was involved. This platform resulted adequate to immobilize proteins and to characterize this process, for further applications as a tool in bioanalysis or biotechnology.Fil: Lazaro Martinez, Juan Manuel. Universidad de Málaga; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Byrne, Agustin Jesus. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; ArgentinaFil: Rodríguez Castellón, Enrique. Universidad de Málaga; EspañaFil: Manrique, Julieta Marina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales y Ciencias de la Salud - Sede Trelew. Laboratorio de Virología y Genética Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Jones, Leandro Roberto. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales y Ciencias de la Salud - Sede Trelew. Laboratorio de Virología y Genética Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Campodallorto, Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; Argentin
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