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1.
J Biol Chem ; 298(10): 102397, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35988640

RESUMO

Sterols in eukaryotic cells play important roles in modulating membrane fluidity and in cell signaling and trafficking. During evolution, a combination of gene losses and acquisitions gave rise to an extraordinary diversity of sterols in different organisms. The sterol C-22 desaturase identified in plants and fungi as a cytochrome P-450 monooxygenase evolved from the first eukaryotic cytochrome P450 and was lost in many lineages. Although the ciliate Tetrahymena thermophila desaturates sterols at the C-22 position, no cytochrome P-450 orthologs are present in the genome. Here, we aim to identify the genes responsible for the desaturation as well as their probable origin. We used gene knockout and yeast heterologous expression approaches to identify two putative genes, retrieved from a previous transcriptomic analysis, as sterol C-22 desaturases. Furthermore, we demonstrate using bioinformatics and evolutionary analyses that both genes encode a novel type of sterol C-22 desaturase that belongs to the large fatty acid hydroxylase/desaturase superfamily and the genes originated by genetic duplication prior to functional diversification. These results stress the widespread existence of nonhomologous isofunctional enzymes among different lineages of the tree of life as well as the suitability for the use of T. thermophila as a valuable model to investigate the evolutionary process of large enzyme families.


Assuntos
Proteínas de Protozoários , Estearoil-CoA Dessaturase , Tetrahymena thermophila , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Saccharomyces cerevisiae , Estearoil-CoA Dessaturase/química , Estearoil-CoA Dessaturase/classificação , Estearoil-CoA Dessaturase/genética , Esteróis/metabolismo , Tetrahymena thermophila/enzimologia , Filogenia , Proteínas de Protozoários/química , Proteínas de Protozoários/classificação , Proteínas de Protozoários/genética
2.
Parasitol Res ; 121(4): 1077-1089, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34665308

RESUMO

The first cestode genomes were obtained by an international consortium led by the Wellcome Sanger Institute that included representative institutions from countries where the sequenced parasites have been studied for decades, in part because they are etiological agents of endemic diseases (Argentina, Uruguay, Mexico, Canada, UK, Germany, Switzerland, Ireland, USA, Japan, and China). After this, several complete genomes were obtained reaching 16 species to date. Cestode genomes have smaller relative size compared to other animals including free-living flatworms. Moreover, the features genome size and repeat content seem to differ in the two analyzed orders. Cyclophyllidean species have smaller genomes and with fewer repetitive content than Diphyllobothriidean species. On average, cestode genomes have 13,753 genes with 6 exons per gene and 41% GC content. More than 5,000 shared cestode proteins were accurately annotated by the integration of gene predictions and transcriptome evidence being more than 40% of these proteins of unknown function. Several gene losses and reduction of gene families were found and could be related to the extreme parasitic lifestyle of these species. The application of cutting-edge sequencing technology allowed the characterization of the terminal sequences of chromosomes that possess unique characteristics. Here, we review the current status of knowledge of complete cestode genomes and place it within a comparative genomics perspective. Multidisciplinary work together with the implementation of new technologies will provide valuable information that can certainly improve our chances to finally eradicate or at least control diseases caused by cestodes.


Assuntos
Cestoides , Infecções por Cestoides , Platelmintos , Animais , Cestoides/genética , Infecções por Cestoides/veterinária , Genômica , Platelmintos/genética , Análise de Sequência de DNA
3.
BMC Genomics ; 18(1): 204, 2017 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-28241794

RESUMO

BACKGROUND: The parasite Echinococcus canadensis (G7) (phylum Platyhelminthes, class Cestoda) is one of the causative agents of echinococcosis. Echinococcosis is a worldwide chronic zoonosis affecting humans as well as domestic and wild mammals, which has been reported as a prioritized neglected disease by the World Health Organisation. No genomic data, comparative genomic analyses or efficient therapeutic and diagnostic tools are available for this severe disease. The information presented in this study will help to understand the peculiar biological characters and to design species-specific control tools. RESULTS: We sequenced, assembled and annotated the 115-Mb genome of E. canadensis (G7). Comparative genomic analyses using whole genome data of three Echinococcus species not only confirmed the status of E. canadensis (G7) as a separate species but also demonstrated a high nucleotide sequences divergence in relation to E. granulosus (G1). The E. canadensis (G7) genome contains 11,449 genes with a core set of 881 orthologs shared among five cestode species. Comparative genomics revealed that there are more single nucleotide polymorphisms (SNPs) between E. canadensis (G7) and E. granulosus (G1) than between E. canadensis (G7) and E. multilocularis. This result was unexpected since E. canadensis (G7) and E. granulosus (G1) were considered to belong to the species complex E. granulosus sensu lato. We described SNPs in known drug targets and metabolism genes in the E. canadensis (G7) genome. Regarding gene regulation, we analysed three particular features: CpG island distribution along the three Echinococcus genomes, DNA methylation system and small RNA pathway. The results suggest the occurrence of yet unknown gene regulation mechanisms in Echinococcus. CONCLUSIONS: This is the first work that addresses Echinococcus comparative genomics. The resources presented here will promote the study of mechanisms of parasite development as well as new tools for drug discovery. The availability of a high-quality genome assembly is critical for fully exploring the biology of a pathogenic organism. The E. canadensis (G7) genome presented in this study provides a unique opportunity to address the genetic diversity among the genus Echinococcus and its particular developmental features. At present, there is no unequivocal taxonomic classification of Echinococcus species; however, the genome-wide SNPs analysis performed here revealed the phylogenetic distance among these three Echinococcus species. Additional cestode genomes need to be sequenced to be able to resolve their phylogeny.


Assuntos
Equinococose/genética , Echinococcus/genética , Genoma de Protozoário , Animais , Proteínas Argonautas/antagonistas & inibidores , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Hibridização Genômica Comparativa , Mapeamento de Sequências Contíguas , Ilhas de CpG , Metilação de DNA , Equinococose/parasitologia , Equinococose/patologia , Echinococcus/classificação , Echinococcus/metabolismo , Humanos , Sequências Repetitivas Dispersas/genética , Filogenia , Polimorfismo de Nucleotídeo Único , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
4.
Trop Med Int Health ; 21(2): 166-75, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26610060

RESUMO

OBJECTIVE: To systematically review publications on Echinococcus granulosus sensu lato species/genotypes reported in domestic intermediate and definitive hosts in South America and in human cases worldwide, taking into account those articles where DNA sequencing was performed; and to analyse the density of each type of livestock that can act as intermediate host, and features of medical importance such as cyst organ location. METHODS: Literature search in numerous databases. We included only articles where samples were genotyped by sequencing since to date it is the most accurate method to unambiguously identify all E. granulosus s. l. genotypes. Also, we report new E. granulosus s. l. samples from Argentina and Uruguay analysed by sequencing of cox1 gene. RESULTS: In South America, five countries have cystic echinococcosis cases for which sequencing data are available: Argentina, Brazil, Chile, Peru and Uruguay, adding up 1534 cases. E. granulosus s. s. (G1) accounts for most of the global burden of human and livestock cases. Also, E. canadensis (G6) plays a significant role in human cystic echinococcosis. Likewise, worldwide analysis of human cases showed that 72.9% are caused by E. granulosus s. s. (G1) and 12.2% and 9.6% by E. canadensis G6 and G7, respectively. CONCLUSIONS: E. granulosus s. s. (G1) accounts for most of the global burden followed by E. canadensis (G6 and G7) in South America and worldwide. This information should be taken into account to suit local cystic echinococcosis control and prevention programmes according to each molecular epidemiological situation.


Assuntos
Equinococose/parasitologia , Echinococcus granulosus/genética , Genótipo , Gado/parasitologia , Animais , Equinococose/veterinária , Echinococcus , Humanos , América do Sul
5.
Life (Basel) ; 13(12)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38137887

RESUMO

Helminth parasites cause debilitating-sometimes fatal-diseases in humans and animals. Despite their impact on global health, mechanisms underlying host-parasite interactions are still poorly understood. One such mechanism involves the exchange of extracellular vesicles (EVs), which are membrane-enclosed subcellular nanoparticles. To date, EV secretion has been studied in helminth parasites, including EV protein content. However, information is highly heterogeneous, since it was generated in multiple species, using varied protocols for EV isolation and data analysis. Here, we compared the protein cargo of helminth EVs to identify common markers for each taxon. For this, we integrated published proteomic data and performed a comparative analysis through an orthology approach. Overall, only three proteins were common in the EVs of the seven analyzed species. Additionally, varied repertoires of proteins with moonlighting activity, vaccine antigens, canonical and non-canonical proteins related to EV biogenesis, taxon-specific proteins of unknown function and RNA-binding proteins were observed in platyhelminth and nematode EVs. Despite the lack of consensus on EV isolation protocols and protein annotation, several proteins were shown to be consistently detected in EV preparations from organisms at different taxa levels, providing a starting point for a selective biochemical characterization.

6.
Am J Biol Anthropol ; 181(4): 597-610, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37323114

RESUMO

OBJECTIVES: The objective of this study was to enhance our understanding of the population history in South America, specifically Northwestern Argentina, by analyzing complete ancient mitogenomes of individuals from the Ojo de Agua archeological site (970 BP) in Quebrada del Toro (Salta, Argentina). MATERIALS AND METHODS: We analyzed teeth from four individuals from the site Ojo de Agua (970 ± 60 BP), located in Quebrada del Toro (Andean region of Northwestern Argentina). DNA extracts were converted to double-stranded DNA libraries and indexed using unique dual-indexing primer combinations. DNA libraries were then enriched for the complete mitochondrial genome, pooled at equimolar concentrations, and sequenced on an Illumina® MiSeq™ platform. Reads from high quality libraries were trimmed, merged, and then mapped to the revised Cambridge Reference Sequence. The aDNA damage patterns were assessed and contamination estimated. Finally, variants were called, filtered, and the consensus mitogenome was constructed and used for haplogroup assignment. We also compiled available mitogenome sequences from ancient and present-day populations from the Southcentral Andes and other surrounding regions in Argentina. Maximum Likelihood and Bayesian phylogenetic reconstructions were obtained using the generated dataset. RESULTS: We successfully obtained the complete mitogenome sequence from one individual with an average depth coverage of 102X. We discovered a novel haplotype that was assigned to haplogroup D1. Phylogenetic reconstructions suggests that this haplotype falls within the sister branches of the D1j lineage, forming a well-supported clade. The estimate TMRCA of this clade that includes D1j and its sister branches ranged between 12,535 and 18,669 ya. DISCUSSION: The sequence analyzed in this study represents the first ancient mitogenome from within the valley region in Northwestern Argentina. We found that a representative of a lineage highly associated with D1j was already present approximately 1000 BP in the region. Our results agree with the proposed origin of D1j in other regions north of Patagonia and independent of the Pacific coast fast migratory route, contrary to what was originally hypothesized. This study highlights the lack of information regarding pre-Hispanic genetic diversity and contributes to the knowledge about the peopling process in South America.


OBJETIVOS: El objetivo de este estudio fue contribuir a mejorar la comprensión del poblamiento de Sudamérica, específicamente del Noroeste Argentino, mediante el análisis de mitogenomas antiguos completos de individuos del sitio arqueológico Ojo de Agua (970 AP), Quebrada del Toro (Salta, Argentina). MATERIALES Y MÉTODOS: Se analizaron dientes de cuatro individuos del sitio Ojo de Agua (970 ± 60 AP), ubicado en la Quebrada del Toro (región andina del Noroeste Argentino). A partir de los extractos de ADN se armaron librerías doble cadena y se indexaron utilizando combinaciones únicas de pares de cebadores. Las librerías fueron luego enriquecidas en ADN mitocondrial, llevadas a concentraciones equimolares y secuenciadas en una plataforma Illumina® MiSeq™. Las lecturas de las librerías de alta calidad fueron recortadas, fusionadas y, posteriormente, alineadas con la Secuencia de Referencia de Cambridge revisada. Se evaluaron los patrones de daño del ADNa y se estimó la contaminación. Por último, se identificaron las variantes, se filtraron y se construyó el mitogenoma consenso, que se utilizó para la asignación de haplogrupos. Además, se recopilaron secuencias de mitogenomas disponibles para poblaciones pre-hispánicas y actuales de los Andes Centrosur y otras regiones adyacentes de Argentina. Utilizando el conjunto de datos generado, se obtuvieron reconstrucciones filogenéticas mediante Máxima Verosimilitud y estimación Bayesiana. RESULTADOS: Se obtuvo la secuencia completa del mitogenoma de un individuo con una profundidad media de 102X. Esta secuencia corresponde a un nuevo haplotipo que fue asignado al haplogrupo D1. Las reconstrucciones filogenéticas sugirieron que este haplotipo se encuentra dentro del grupo hermano del linaje D1j, conformando un clado bien soportado. La datación estimada para este clado que contiene a D1j y a todo su grupo hermano fue de entre 12.535 y 18.669 años atrás. DISCUSIÓN: La secuencia analizada en este estudio representa el primer mitogenoma antiguo de la región valliserrana del Noroeste Argentino. Se halló que un representante de un linaje altamente asociado con D1j ya estaba presente hace aproximadamente 1000 años AP en la región. Nuestros resultados concuerdan con un origen de D1j en otras regiones al norte de la Patagonia, e independientemente de la ruta migratoria rápida por la costa del Pacífico, en contraposición a lo planteado inicialmente. Este estudio pone en evidencia la falta de información que se tiene actualmente sobre la diversidad genética en tiempos prehispánicos y contribuye al conocimiento del proceso de poblamiento de Sudamérica.


Assuntos
Genoma Mitocondrial , Humanos , Argentina , Genoma Mitocondrial/genética , Filogenia , Teorema de Bayes , DNA Mitocondrial/genética , América do Sul
7.
Sci Rep ; 11(1): 4108, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33602998

RESUMO

In December 2019, rising pneumonia cases caused by a novel ß-coronavirus (SARS-CoV-2) occurred in Wuhan, China, which has rapidly spread worldwide, causing thousands of deaths. The WHO declared the SARS-CoV-2 outbreak as a public health emergency of international concern, since then several scientists are dedicated to its study. It has been observed that many human viruses have codon usage biases that match highly expressed proteins in the tissues they infect and depend on the host cell machinery for the replication and co-evolution. In this work, we analysed 91 molecular features and codon usage patterns for 339 viral genes and 463 human genes that consisted of 677,873 codon positions. Hereby, we selected the highly expressed genes from human lung tissue to perform computational studies that permit to compare their molecular features with those of SARS, SARS-CoV-2 and MERS genes. The integrated analysis of all the features revealed that certain viral genes and overexpressed human genes have similar codon usage patterns. The main pattern was the A/T bias that together with other features could propitiate the viral infection, enhanced by a host dependant specialization of the translation machinery of only some of the overexpressed genes. The envelope protein E, the membrane glycoprotein M and ORF7 could be further benefited. This could be the key for a facilitated translation and viral replication conducting to different comorbidities depending on the genetic variability of population due to the host translation machinery. This is the first codon usage approach that reveals which human genes could be potentially deregulated due to the codon usage similarities between the host and the viral genes when the virus is already inside the human cells of the lung tissues. Our work leaded to the identification of additional highly expressed human genes which are not the usual suspects but might play a role in the viral infection and settle the basis for further research in the field of human genetics associated with new viral infections. To identify the genes that could be deregulated under a viral infection is important to predict the collateral effects and determine which individuals would be more susceptible based on their genetic features and comorbidities associated.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/genética , Infecções por Coronavirus/virologia , Códon/genética , Uso do Códon , Biologia Computacional/métodos , Coronavirus/genética , Infecções por Coronavirus/metabolismo , Genes Virais , Genoma Viral , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Filogenia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , SARS-CoV-2/genética
8.
Front Cell Infect Microbiol ; 10: 607348, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33392111

RESUMO

Background: Most patients with respiratory syncytial virus (RSV) infection requiring hospitalization have no risk factors for severe disease. Genetic variation in the receptor for the Fc portion of IgG (FcγR) determines their affinity for IgG subclasses driving innate and adaptive antiviral immunity. We investigated the relationship between FcγRIIa-H131R polymorphism and RSV disease. Methods: Blood samples were collected from 182 infants ≤24-month-old (50 uninfected, 114 RSV-infected with moderate course and 18 suffering severe disease). FcγRIIa-H131R SNP genotypic frequencies (HH, HR, RR) and anti-RSV IgG1, IgG2 and IgG3 levels were studied. Results: Genotypic frequencies for FcγRIIa-H131R SNP were comparable between uninfected and RSV-infected infants. In contrast, we found a significant higher frequency of HH genotype in severe RSV-infected children compared to moderate patients. Among severe group, HH infants presented more factors associated to severity than HR or RR patients did. Furthermore, compared to moderate RSV-infected infants, severe patients showed higher levels of anti-RSV IgG1 and IgG3. Conclusions: We found an association between an FcγRIIa (H131) polymorphism and severe RSV disease, which points towards a critical role for interactions between FcγRs and immune complexes in RSV pathogenesis. This genetic factor could also predict the worse outcome and identify those infants at risk during hospitalization.


Assuntos
Receptores de IgG , Infecções por Vírus Respiratório Sincicial , Criança , Humanos , Lactente , Polimorfismo Genético , Receptores de IgG/genética , Infecções por Vírus Respiratório Sincicial/genética , Vírus Sinciciais Respiratórios
9.
Front Genet ; 10: 708, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31440275

RESUMO

The first parasitic helminth genome sequence was published in 2007; since then, only ∼200 genomes have become available, most of them being draft assemblies. Nevertheless, despite the medical and economical global impact of helminthic infections, parasite genomes in public databases are underrepresented. Recently, through an integrative approach involving morphological, genetic, and ecological aspects, we have demonstrated that the complete life cycle of Echinococcus oligarthrus (Cestoda: Taeniidae) is present in South America. The neotropical E. oligarthrus parasite is capable of developing in any felid species and producing human infections. Neotropical echinococcosis is poorly understood yet and requires a complex medical examination to provide the appropriate intervention. Only a few cases of echinococcosis have been unequivocally identified and reported as a consequence of E. oligarthrus infections. Regarding phylogenetics, the analyses of mitogenomes and nuclear datasets have resulted in discordant topologies, and there is no unequivocal taxonomic classification of Echinococcus species so far. In this work, we sequenced and assembled the genome of E. oligarthrus that was isolated from agoutis (Dasyprocta azarae) naturally infected and performed the first comparative genomic study of a neotropical Echinococcus species. The E. oligarthrus genome assembly consisted of 86.22 Mb which showed ∼90% identity and 76.3% coverage with Echinococcus multilocularis and contained the 85.0% of the total expected genes. Genetic variants analysis of whole genome revealed a higher rate of intraspecific genetic variability (23,301 SNPs; 0.22 SNPs/kb) rather than for the genomes of E. multilocularis and Echinococcus canadensis G7 but lower with respect to Echinococcus granulosus G1. Comparative genomics against E. multilocularis, E. granulosus G1, and E. canadensis G7 revealed 38,762, 125,147, and 170,049 homozygous polymorphic sites, respectively, indicating a higher genetic distance between E. oligarthrus and E. granulosus sensu lato species. The SNP distribution in chromosomes revealed a higher SNP density in the longest chromosomes. Phylogenetic analysis using whole-genome SNPs demonstrated that E. oligarthrus is one of the basal species of the genus Echinococcus and is phylogenetically closer to E. multilocularis. This work sheds light on the Echinococcus phylogeny and settles the basis to study sylvatic Echinococcus species and their developmental evolutionary features.

10.
Mol Biochem Parasitol ; 225: 54-66, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30081061

RESUMO

The species of the genus Echinococcus are parasitic platyhelminths that cause echinococcosis and exert a global burden on public and animal health. Here we performed codon usage bias and comparative genomic analyses using whole genome and expression data of three Echinococcus species. The study of 4,710,883 codons, two orders of magnitude more than in previous research works, showed that the codon usage in Echinococcus genes is biased towards the pyrimidines T and C ending codons, with an average effective number of codons equal to 57 revealing a low codon usage bias. The gene annotations and the expression profile of 7613 genes allowed to accurately determine 27 optimal codons for the Echinococcus species, most of them ending in G/C. Approximately the 30% of Echinococcus genes analysed exhibits higher codon usage bias as well as a higher expression profile. Neutrality-plots demonstrated that the selection pressure is the main evolutionary force shaping the codon usage with a contribution of 80%. Comparative genome analyses among several tapeworm species revealed that codon usage patterns are a conserved trait in cestodes parasites. Since cestodes parasites take advantage of the host protein synthesis pathways, this study could provide valuable information associated with the parasite-host relationship that would be useful to determine which host's factors are relevant for shaping the codon usage.


Assuntos
Códon , DNA de Helmintos/genética , Echinococcus/genética , Genoma Helmíntico , RNA de Helmintos/genética , Animais
11.
PLoS Negl Trop Dis ; 12(2): e0006267, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29425245

RESUMO

BACKGROUND: Cestodes are a diverse group of parasites, some of them being agents of neglected diseases. In cestodes, little is known about the functional properties of G protein coupled receptors (GPCRs) which have proved to be highly druggable targets in other organisms. Notably, serotoninergic G-protein coupled receptors (5-HT GPCRs) play major roles in key functions like movement, development and reproduction in parasites. METHODOLOGY/PRINCIPAL FINDINGS: Three 5-HT GPCRs from Echinococcus granulosus and Mesocestoides corti were cloned, sequenced, bioinformatically analyzed and functionally characterized. Multiple sequence alignment with other GPCRs showed the presence of seven transmembrane segments and conserved motifs but interesting differences were also observed. Phylogenetic analysis grouped these new sequences within the 5-HT7 clade of GPCRs. Molecular modeling showed a striking resemblance in the spatial localization of key residues with their mammalian counterparts. Expression analysis using available RNAseq data showed that both E. granulosus sequences are expressed in larval and adult stages. Localization studies performed in E. granulosus larvae with a fluorescent probe produced a punctiform pattern concentrated in suckers. E. granulosus and M. corti larvae showed an increase in motility in response to serotonin. Heterologous expression revealed elevated levels of cAMP production in response to 5-HT and two of the GPCRs showed extremely high sensitivity to 5-HT (picomolar range). While each of these GPCRs was activated by 5-HT, they exhibit distinct pharmacological properties (5-HT sensitivity, differential responsiveness to ligands). CONCLUSIONS/SIGNIFICANCE: These data provide the first functional report of GPCRs in parasitic cestodes. The serotoninergic GPCRs characterized here may represent novel druggable targets for antiparasitic intervention.


Assuntos
Cestoides/fisiologia , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Motivos de Aminoácidos , Animais , Cestoides/genética , Cestoides/crescimento & desenvolvimento , Infecções por Cestoides/tratamento farmacológico , Clonagem Molecular , Biologia Computacional , Echinococcus granulosus/genética , Echinococcus granulosus/fisiologia , Larva/fisiologia , Mesocestoides/genética , Mesocestoides/crescimento & desenvolvimento , Mesocestoides/fisiologia , Modelos Moleculares , Filogenia , Conformação Proteica , Receptores Acoplados a Proteínas G/genética , Alinhamento de Sequência , Serotonina/farmacologia
12.
Mol Biochem Parasitol ; 214: 91-100, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28385564

RESUMO

MicroRNAs (miRNAs), a class of small non-coding RNAs, are key regulators of gene expression at post-transcriptional level and play essential roles in biological processes such as development. MiRNAs silence target mRNAs by binding to complementary sequences in the 3'untranslated regions (3'UTRs). The parasitic helminths of the genus Echinococcus are the causative agents of echinococcosis, a zoonotic neglected disease. In previous work, we performed a comprehensive identification and characterization of Echinococcus miRNAs. However, current knowledge about their targets is limited. Since target prediction algorithms rely on complementarity between 3'UTRs and miRNA sequences, a major limitation is the lack of accurate sequence information of 3'UTR for most species including parasitic helminths. We performed RNA-seq and developed a pipeline that integrates the transcriptomic data with available genomic data of this parasite in order to identify 3'UTRs of Echinococcus canadensis. The high confidence set of 3'UTRs obtained allowed the prediction of miRNA targets in Echinococcus through a bioinformatic approach. We performed for the first time a comparative analysis of miRNA targets in Echinococcus and Taenia. We found that many evolutionarily conserved target sites in Echinococcus and Taenia may be functional and under selective pressure. Signaling pathways such as MAPK and Wnt were among the most represented pathways indicating miRNA roles in parasite growth and development. Genome-wide identification and characterization of miRNA target genes in Echinococcus provide valuable information to guide experimental studies in order to understand miRNA functions in the parasites biology. miRNAs involved in essential functions, especially those being absent in the host or showing sequence divergence with respect to host orthologs, might be considered as novel therapeutic targets for echinococcosis control.


Assuntos
Echinococcus/crescimento & desenvolvimento , Echinococcus/genética , Regulação da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , Regiões 3' não Traduzidas , Animais , Perfilação da Expressão Gênica , Genes de Helmintos , Genômica , Análise de Sequência de RNA , Taenia/genética , Taenia/crescimento & desenvolvimento
13.
Parasit Vectors ; 8: 83, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25656283

RESUMO

BACKGROUND: microRNAs (miRNAs), a class of small non-coding RNAs, are key regulators of gene expression at post-transcriptional level and play essential roles in fundamental biological processes such as development and metabolism. The particular developmental and metabolic characteristics of cestode parasites highlight the importance of studying miRNA gene regulation in these organisms. Here, we perform a comprehensive analysis of miRNAs in the parasitic cestode Echinococcus canadensis G7, one of the causative agents of the neglected zoonotic disease cystic echinococcosis. METHODS: Small RNA libraries from protoscoleces and cyst walls of E. canadensis G7 and protoscoleces of E. granulosus sensu stricto G1 were sequenced using Illumina technology. For miRNA prediction, miRDeep2 core algorithm was used. The output list of candidate precursors was manually curated to generate a high confidence set of miRNAs. Differential expression analysis of miRNAs between stages or species was estimated with DESeq. Expression levels of selected miRNAs were validated using poly-A RT-qPCR. RESULTS: In this study we used a high-throughput approach and found transcriptional evidence of 37 miRNAs thus expanding the miRNA repertoire of E. canadensis G7. Differential expression analysis showed highly regulated miRNAs between life cycle stages, suggesting a role in maintaining the features of each developmental stage or in the regulation of developmental timing. In this work we characterize conserved and novel Echinococcus miRNAs which represent 30 unique miRNA families. Here we confirmed the remarkable loss of conserved miRNA families in E. canadensis, reflecting their low morphological complexity and high adaptation to parasitism. CONCLUSIONS: We performed the first in-depth study profiling of small RNAs in the zoonotic parasite E. canadensis G7. We found that miRNAs are the preponderant small RNA silencing molecules, suggesting that these small RNAs could be an essential mechanism of gene regulation in this species. We also identified both parasite specific and divergent miRNAs which are potential biomarkers of infection. This study will provide valuable information for better understanding of the complex biology of this parasite and could help to find new potential targets for therapy and/or diagnosis.


Assuntos
Equinococose/veterinária , Echinococcus/genética , MicroRNAs/genética , RNA de Helmintos/genética , Doenças dos Ovinos/parasitologia , Doenças dos Suínos/parasitologia , Animais , Sequência de Bases , Equinococose/parasitologia , Echinococcus/isolamento & purificação , Echinococcus/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/metabolismo , Dados de Sequência Molecular , RNA de Helmintos/metabolismo , Análise de Sequência de RNA , Ovinos , Suínos
14.
Int J Parasitol ; 45(4): 253-67, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25659494

RESUMO

Echinococcosis is a worldwide zoonosis of great public health concern, considered a neglected disease by the World Health Organisation. The cestode parasites Echinococcus granulosus sensu lato (s. l.) and Echinococcus multilocularis are the main aetiological agents. In the intermediate host, these parasites display particular developmental traits that lead to different patterns of disease progression. In an attempt to understand the causes of these differences, we focused on the analysis of microRNAs (miRNAs), small non-coding regulatory RNAs with major roles in development of animals and plants. In this work, we analysed the small RNA expression pattern of the metacestode, the stage of sanitary relevance, and provide a detailed description of Echinococcus miRNAs. Using high-throughput small RNA sequencing, we believe that we have carried out the first experimental identification of miRNAs in E. multilocularis and have expanded the Echinococcus miRNA catalogue to 38 miRNA genes, including one miRNA only present in E. granulosus s. l. Our findings show that although both species share the top five highest expressed miRNAs, 13 are differentially expressed, which could be related to developmental differences. We also provide evidence that uridylation is the main miRNA processing mechanism in Echinococcus spp. These results provide detailed information on Echinococcus miRNAs, which is the first step in understanding their role in parasite biology and disease establishment and/or progression, and their future potential use as drug or diagnostic targets.


Assuntos
Echinococcus granulosus/genética , Echinococcus multilocularis/genética , MicroRNAs/análise , Animais , Argentina , Echinococcus granulosus/crescimento & desenvolvimento , Echinococcus granulosus/isolamento & purificação , Echinococcus multilocularis/crescimento & desenvolvimento , Echinococcus multilocularis/isolamento & purificação , Feminino , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Camundongos , MicroRNAs/genética , Processamento Pós-Transcricional do RNA , Suínos
15.
Notas enferm. (Córdoba) ; 18(32): 5-14, dic. 2018. ilus, tab
Artigo em Espanhol | LILACS, BDENF, BINACIS, UNISALUD | ID: biblio-1005446

RESUMO

El infarto agudo de miocardio (IAM) representa la tercera causa de morbimortalidad en el país. Tener datos sobre la realidad de esta entidad en la institución es de suma importancia como punto de partida para el desarrollo de políticas de prevención, así también mejorar el tratamiento, cuidado y calidad de atención al paciente. OBJETIVO: Determinar el perfil epidemiológico de la población que se les indica tratamiento con Tirofiban durante infarto agudo de miocardio (IAM)...


Acutemyocardialinfarction (AMI) represents the third cause ofmorbidity and mortality in the country. Having information about the reality of this entity in the institution is of the utmost importance as a starting point for the development of prevention policies, as well as improving the treatment, care and quality of patientcare. OBJECTIVE: To determine the epidemiological profile of the population that is being treated with Tirofiban during acute myocardialinfarction (AMI)...


Assuntos
Humanos , Masculino , Adulto , Angioplastia , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Infarto do Miocárdio , Infarto do Miocárdio/complicações , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/epidemiologia , Cuidados de Enfermagem
16.
Notas enferm. (Córdoba) ; 17(30): 13-14, nov. 2017.
Artigo em Espanhol | LILACS, BDENF, BINACIS, UNISALUD | ID: biblio-907854

RESUMO

El objetivo de este trabajo es lograr sistematizar los cuidados de enfermeria al paciente con indicacion de angioplastia transluminal coronaria percutanea en el servicio de Hemodinamia del Sanatorio Allende.


Assuntos
Humanos , Angioplastia , Cuidados de Enfermagem , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios
17.
Braz J Otorhinolaryngol ; 75(5): 665-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19893933

RESUMO

UNLABELLED: Changes, destructions and interruptions in middle ear ossicular chain architecture may be caused by infection, trauma, tumors, congenital alterations or prior surgeries. Nonetheless, infectious and inflammatory processes, focal or generalized which affect the middle ear are the most prevalent, causing a great demand for ossiculoplasty. Biosilicato is a new material which can be used in the middle ear with the goal of reconstructing the ossicular chain. It is a bioactive type A vitroceramic, in other words, it binds to bone or soft tissue in a matter of a few hours, thanks to the formation of hydroxy-carbonateapatatie in its contact surface when in contact with body fluids. AIMS: The goal of the present paper is to assess biosilicate ototoxicity and vestibular toxicity in experimental animals, for later use in humans. MATERIALS AND METHODS: This a clinical and experimental study in which otoacoustic emissions were performed before and after the placement of Biosilicate in the middle ear of experimental animals and a scanning electron microscopy was carried out in the cochlea, saccule, utriculus and macula of the semicircular canals after 30 and 90 days to assess oto and vestibular toxicity. RESULTS: There were no signs of oto or vestibular toxicity in any of the groups associated with biosilicate. CONCLUSION: Biosilicate is a safe material to be used in ossiculoplasties.


Assuntos
Materiais Biocompatíveis/toxicidade , Cerâmica/toxicidade , Orelha Interna/efeitos dos fármacos , Silicatos/toxicidade , Animais , Avaliação Pré-Clínica de Medicamentos , Orelha Interna/ultraestrutura , Cobaias , Masculino , Microscopia Eletrônica de Varredura , Prótese Ossicular , Substituição Ossicular , Emissões Otoacústicas Espontâneas/efeitos dos fármacos
18.
Braz. j. otorhinolaryngol. (Impr.) ; 75(5): 665-668, Sept.-Oct. 2009. ilus
Artigo em Inglês, Português | LILACS | ID: lil-530088

RESUMO

Changes, destructions and interruptions in middle ear ossicular chain architecture may be caused by infection, trauma, tumors, congenital alterations or prior surgeries. Nonetheless, infectious and inflammatory processes, focal or generalized which affect the middle ear are the most prevalent, causing a great demand for ossiculoplasty. Biosilicato® is a new material which can be used in the middle ear with the goal of reconstructing the ossicular chain. It is a bioactive type A vitroceramic, in other words, it binds to bone or soft tissue in a matter of a few hours, thanks to the formation of hydroxy-carbonateapatatie in its contact surface when in contact with body fluids. AIMS: The goal of the present paper is to assess biosilicate ototoxicity and vestibular toxicity in experimental animals, for later use in humans. MATERIALS AND METHODS: This a clinical and experimental study in which otoacoustic emissions were performed before and after the placement of Biosilicate in the middle ear of experimental animals and a scanning electron microscopy was carried out in the cochlea, saccule, utriculus and macula of the semicircular canals after 30 and 90 days to assess oto and vestibular toxicity. RESULTS: There were no signs of oto or vestibular toxicity in any of the groups associated with biosilicate. CONCLUSION: Biosilicate is a safe material to be used in ossiculoplasties


As alterações, destruições e interrupções da arquitetura da cadeia ossicular da orelha média podem ser causadas por infecções, trauma, tumores, alterações congênitas ou cirurgias prévias. Entretanto os processos inflamatórios e infecciosos, focais ou generalizados que acometem a orelha média são os mais prevalentes, gerando uma enorme demanda de ossiculoplastias. O Biosilicato® é um novo material que pode ser usado em orelhas médias com o objetivo de reconstruir a cadeia ossicular. Constitui-se de uma vitrocerâmica bioativa do tipo A, ou seja, que se liga a tecido ósseo ou a tecido mole em algumas horas, devido à formação de hidroxicarbonatoapatita em sua superfície de contato quando em contato com fluidos corpóreos. OBJETIVO: O objetivo deste trabalho é avaliar a ototoxicidade e vestibulotoxicidade do Biosilicato em cobaias, para posterior utilização em humanos. MATERIAL E MÉTODO: Trata-se de um estudo clínico e experimental, onde foram realizadas emissões otoacústicas antes e após a colocação de Biosilicato na orelha média de cobaias e realizada microscopia eletrônica de varredura da cóclea, sáculo, utrículo e máculas dos canais semicirculares após 30 e 90 dias para avaliar a oto e vestibulotoxicidade. RESULTADOS: Não houve sinais de oto ou vestibulotoxicidade em nenhum dos grupos relacionados ao Biosilicato. CONCLUSÃO: O Biosilicato é um material seguro para ser usado em ossiculoplastias.


Assuntos
Animais , Cobaias , Masculino , Materiais Biocompatíveis/toxicidade , Cerâmica/toxicidade , Orelha Interna/efeitos dos fármacos , Silicatos/toxicidade , Avaliação Pré-Clínica de Medicamentos , Orelha Interna/ultraestrutura , Microscopia Eletrônica de Varredura , Prótese Ossicular , Substituição Ossicular , Emissões Otoacústicas Espontâneas/efeitos dos fármacos
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