194 research outputs found
Identification of the HSP70-II gene in Leishmania braziliensis HSP70 locus: genomic organization and UTRs characterization
<p>Abstract</p> <p>Background</p> <p>The heat stress suffered by <it>Leishmania sp </it>during its digenetic life-cycle is a key trigger for its stage differentiation. In <it>Leishmania </it>subgenera two classes of <it>HSP70 </it>genes differing in their 3' UTR were described. Although the presence of <it>HSP70</it>-<it>I </it>genes was previously suggested in <it>Leishmania (Viannia) braziliensis</it>, <it>HSP70</it>-<it>II </it>genes had been reluctant to be uncovered.</p> <p>Results</p> <p>Here, we report the existence of two types of <it>HSP70 </it>genes in <it>L. braziliensis </it>and the genomic organization of the <it>HSP70 </it>locus. RT-PCR experiments were used to map the untranslated regions (UTR) of both types of genes. The 3' UTR-II has a low sequence identity (55-57%) when compared with this region in other <it>Leishmania </it>species. In contrast, the 5' UTR, common to both types of genes, and the 3' UTR-I were found to be highly conserved among all <it>Leishmania </it>species (77-81%). Southern blot assays suggested that <it>L. braziliensis </it><it>HSP70 </it>gene cluster may contain around 6 tandemly-repeated <it>HSP70</it>-<it>I </it>genes followed by one <it>HSP70</it>-<it>II </it>gene, located at chromosome 28. Northern blot analysis indicated that levels of both types of mRNAs are not affected by heat shock.</p> <p>Conclusions</p> <p>This study has led to establishing the composition and structure of the HSP70 locus of <it>L. braziliensis</it>, complementing the information available in the GeneDB genome database for this species. <it>L. braziliensis </it><it>HSP70 </it>gene regulation does not seem to operate by mRNA stabilization as occurs in other <it>Leishmania </it>species.</p
SARS-CoV2 infection: the role of cytokines in COVID-19 disease
Elsevier concede permiso para que toda su investigación relacionada con COVID-19 que esté disponible en el centro de recursos COVID-19 -incluido el contenido de esta investigación- esté inmediatamente disponible en PubMed Central y otros repositorios financiados con fondos públicos, como la base de datos COVID de la OMS, con derechos para su reutilización y análisis de investigación sin restricciones en cualquier forma o por cualquier medio con reconocimiento de la fuente original. Estos permisos son concedidos gratuitamente por Elsevier mientras permanezca activo el centro de recursos COVID-19.COVID-19 disease, caused by infection with SARS-CoV-2, is related to a series of physiopathological mechanisms that mobilize a wide variety of biomolecules, mainly immunological in nature. In the most severe cases, the prognosis can be markedly worsened by the hyperproduction of mainly proinflammatory cytokines, such as IL-1, IL-6, IL-12, IFN-γ, and TNF-α, preferentially targeting lung tissue. This study reviews published data on alterations in the expression of different cytokines in patients with COVID-19 who require admission to an intensive care unit. Data on the implication of cytokines in this disease and their effect on outcomes will support the design of more effective approaches to the management of COVID-19.Este estudio ha contado con el apoyo del grupo de investigación BIO277 (Junta de Andalucía) y del Departamento de Enfermería de la Universidad de Granada
Sequence analysis of the 3-untranslated region of HSP70 (type I) genes in the genus Leishmania: Its usefulness as a molecular marker for species identification
Background: The Leishmaniases are a group of clinically diverse diseases caused by parasites of the genus Leishmania. To distinguish between species is crucial for correct diagnosis and prognosis as well as for treatment decisions. Recently, sequencing of the HSP70 coding region has been applied in phylogenetic studies and for identifying of Leishmania species with excellent results. Methods: In the present study, we analyzed the 3-untranslated region (UTR) of Leishmania HSP70-type I gene from 24 strains representing eleven Leishmania species in the belief that this non-coding region would have a better discriminatory capacity for species typing than coding regions. Results: It was observed that there was a remarkable degree of sequence conservation in this region, evenbetween species of the subgenus Leishmania and Viannia. In addition, the presence of many microsatellites was a common feature of the 3-UTR of HSP70-I genes in the Leishmania genus. Finally, we constructed dendrograms based on global sequence alignments of the analyzed Leishmania species and strains, the results indicated that this particular region of HSP70 genes might be useful for species (or species complex) typing, improving for particular species the discrimination capacity of phylogenetic trees based on HSP70 coding sequences. Given the large size variation of the analyzed region between the Leishmania and Viannia subgenera, direct visualization of the PCR amplification product would allow discrimination between subgenera, and a HaeIII-PCR-RFLP analysis might be used for differentiating some species within each subgenera. Conclusions: Sequence and hylogenetic analyses indicated that this region, which is readily amplified using a single pair of primers from both Old and New World Leishmania species, might be useful as a molecular marker for species discrimination. © 2012 Requena et al.; licensee BioMed Central Ltd.Ministerio de Ciencia y Tecnología (BFU2009-08986); Fondo de Investigaciones Sanitarias (ISCIII-RETIC RD06/0021/0008-FEDER and ISCIII-RETIC RD06/0021/0009-FEDER); Agencia Española de Cooperación Internacional para el Desarrollo (AECID, A/024740/09); Fundación Ramón ArecesPeer Reviewe
A dataset of proteins associated with Trypanosoma cruzi LYT1 mRNAs
Post-transcriptional gene regulation in Trypanosoma cruzi, the etiological agent of Chagas disease, plays a critical role in ensuring that the parasite successfully completes its life cycle in both of its obligate hosts: insect vector and mammals. This regulation is basically governed by RNA binding proteins (RBPs) through their interactions with cis-elements located in the UTRs of their mRNA targets. LYT1 gene, coding for a virulence factor of T. cruzi, is expressed into two isoforms: kLYT1 and mLYT1, which play different functions according to their cellular location and parasite life-cycle stages. Whereas kLYT1 exhibits a regulatory role during the epimastigote-to-metacyclic trypomastigote stage transition, mLYT1 acts as a pore-forming protein, relevant for host cell invasion and parasite intracellular survival. Considering the LYT1 biological relevance and the fact that this is a protein exclusive of T. cruzi, the protein and its mechanisms regulating the alternative gene expression products are promising targets for therapeutic intervention. In this work, an experimental approach consisting of pull-downs assays followed by proteomic analyzes was carried out to identify the proteins interacting with the different LYT1 mRNAs. The dataset presented here was obtained through three biological replicates using all the different UTRs characterized in the LYT1 mRNAs (i.e., 5´UTR kLYT1, 5´UTR mLYT1, and I and II-type 3´UTRs) as baits, and protein extracts from epimastigotes and trypomastigotes of the 058 PUJ (DTU I) strain. Bound proteins were analyzed by liquid chromatography coupled to mass spectrometry (LC/MS). As a control of non-specificity, the same protein extracts were incubated with Leishmania braziliensis rRNA and the bound proteins also identified by LC/MS. In all, 1,557 proteins were identified, 313 of them were found in at least two replicates and 18 proteins were exclusively associated with the LYT1 baits. Of these, six proteins have motifs related to RNA binding, and seven remain annotated as hypothetical proteins. Remarkably, three of these hypothetical proteins also contain nucleic acid binding motifs. This knowledge, beside expanding the known T. cruzi proteome, gains insight into putative regulatory proteins responsible for alternative LYT1 mRNAs processing. Raw mass spectrometry data are available via MassIVE proteome Xchange with identifier PXD027371
Detection of Trypanosoma cruzi and Trypanosoma rangeli infection in triatomine vectors by amplification of the histone H2A/SIRE and the sno-RNA-C11 genes
Trypanosoma rangeli is non pathogenic for humans but of important medical and epidemiological interest because it shares vertebrate hosts, insect vectors, reservoirs and geographic areas with T. cruzi, the etiological agent of Chagas disease. Therefore, in this work, we set up two PCR reactions, TcH2AF/R and TrFR2, to distinguish T. cruzi from T. rangeli in mixed infections of vectors based on amplification of the histone H2A/SIRE and the small nucleolar RNA Cl1 genes, respectively. Both PCRs were able to appropriately detect all T. cruzi or T. rangeli experimentally infected-triatomines, as well as the S35/S36 PCR which amplifies the variable region of minicircle kDNA of T. cruzi. In mixed infections, whereas T. cruzi DNA was amplified in 100% of samples with TcH2AF/R and S35/S36 PCRs, T. rangeli was detected in 71% with TrF/R2 and in 6% with S35/S36. In a group of Rhodnius colombiensis collected from Coyaima (Colombia), T. cruzi was identified in 100% with both PCRs and T. rangeli in 14% with TrF/R2 and 10% with S35/S36 PCR. These results show that TcH2AF/R and TrF/R2 PCRs which are capable of recognizing all T. cruzi and T. rangeli strains and lineages could be useful for diagnosis as well as for epidemiological field studies of T. cruzi and T. rangeli vector infections.Embora o Trypanosoma rangeli não seja patogênico para o homem, sua importância médica e epidemiológica reside no fato de compartilhar vetores, reservatórios e áreas geográficas com o Trypanosoma cruzi, agente causal da Doença de Chagas. Neste estudo, para distinguir T. cruzi de T. rangeli em vetores com infecções mistas, se utilizaram duas amplificações de PCR; TcH2AF/R para o gen da histona H2A/SIRE e TrFR2, para um gen repetitivo de ARN nucleolar Cl1 (sno-RNA-Cl1). Assim como a PCR S35/S36, ambas as reações foram capazes de detectar corretamente a presença de T. cruzi ou T. rangeli em triatomíneos infectados experimentalmente. Nas infecções mistas, o ADN de T. cruzi foi amplificado em 100% das amostras quando se utilizaram TcH2AF/R e S35/S36, enquanto T. rangeli foi detectado em 71% delas com os iniciadores TrF/R2 e em 6%, com S35/S36. Adicionalmente, em um grupo de Rhodnius colombiensis coletados na região de Coyaima (Tolima), T. cruzi foi identificado em 100% com ambas PCRs e T. rangeli em 14% delas com os iniciadores TrF/R2 e em 10%, com S35/S36. Estes resultados mostram que as reações de PCR TcH2AF/R e TrF/R2, capazes de reconhecer todas as cepas e linhagens de T. cruzi e T. rangeli, podem ser úteis no diagnóstico e também nos estudos epidemiológicos do campo com vetores infectados pelo T. cruzi e T. rangeli
Leishmania braziliensis replication protein A subunit 1: molecular modelling, protein expression and analysis of its affinity for both DNA and RNA
Variación antigénica de la cepa Munantá de Trypanosoma cruzí después de pase por ratón
This study evaluated the isoenzyme and antigenic changes of Trypanosoma cruzfs Munanta strain after two consecutive passages in mice, using isoenzyme electrophoresis, SDS-PAGE electrophoresis and immunoblot. The results obtained show significant statistical differences within the strain before and after animal passages, which suggests that the mouse is not a recommended model for obtaining the parasite's Munanta strain's trypomastigote forms destined for study of the immune response.Este estudio evaluó los cambios en el perfil isoenzimático y antigénico de la cepa Munantá de Trypanosoma cruzidespués de dos pases consecutivos por ratón, mediante electrofóresis isoenzimática, electrofóresis en PAGE-SDS e immunoblot. Los resultados obtenidos muestran diferencias estadísticamente significativas entre la cepa antes y después de los pases en los animales, lo cual sugiere que el ratón no es un modelo recomendable para obtener las formas tripomastigotas de la cepa Munanta del parásito destinadas a estudios de la respuesta inmune
Educación para el emprendimiento: un enfoque orientado a incrementar las posibilidades de éxito y evitar el fracaso prematuro
La baja tasa de actividad emprendedora en España contrasta con que nuestro país esté considerado como uno de los entonos más propicios para emprender y, todo ello, a pesar del esfuerzo llevado a cabo por los poderes públicos durante los últimos lustros por tratar de impulsar el emprendimiento. Ante esta situación y teniendo en cuenta el riesgo que entraña esta alternativa profesional, conviene plantearse si, antes de incentivar el emprendimiento, sería conveniente dotar a los nuevos emprendedores de las destrezas y habilidades necesarias para incrementar sus posibilidades de éxito y evitar el fracaso de los proyectos incipientes. Este artículo tiene por objeto descubrir los factores que resultan determinantes del éxito en los emprendedores y vincularlos con la educación, de manera que pueda actuarse sobre ellos desde este ámbito y así lograr un emprendimiento de calidad. Para ello, se ha llevado a cabo una revisión bibliográfica de la abundante literatura académica existente sobre la materia. Se partió de una preselección de 398 publicaciones de las que, tras un exhaustivo proceso de filtrado, se terminaron utilizando 82. Tras el análisis de estas fuentes, se concluyó que, para incrementar la tasa de emprendedores y lograr un emprendimiento de calidad, es necesario integrar en el sistema educativo las capacidades y los valores emprendedores desde temprana edad, elaborando una estrategia formativa orientada a dotar a los nuevos emprendedores de los factores que resulten determinantes para el éxito y eviten el fracaso prematuro.2021-2
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