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1.
Sci Rep ; 11(1): 5554, 2021 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-33692368

RESUMEN

Dengue virus causes dengue hemorrhagic fever (DHF) and has been associated to fatal cases worldwide. The liver is one of the most important target tissues in severe cases, due to its intense viral replication and metabolic role. microRNAs role during infection is crucial to understand the regulatory mechanisms of DENV infection and can help in diagnostic and anti-viral therapies development. We sequenced the miRNome of six fatal cases and compared to five controls, to characterize the human microRNAs expression profile in the liver tissue during DHF. Eight microRNAs were differentially expressed, including miR-126-5p, a regulatory molecule of endothelial cells, miR-122-5p, a liver specific homeostasis regulator, and miR-146a-5p, an interferon-regulator. Enrichment analysis with predicted target genes of microRNAs revealed regulatory pathways of apoptosis, involving MAPK, RAS, CDK and FAS. Immune response pathways were related to NF- kB, CC and CX families, IL and TLR. This is the first description of the human microRNA and isomicroRNA profile in liver tissues from DHF cases. The results demonstrated the association of miR-126-5p, miR-122-5p and miR-146a-5p with DHF liver pathogenesis, involving endothelial repair and vascular permeability regulation, control of homeostasis and expression of inflammatory cytokines.


Asunto(s)
Virus del Dengue/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Hígado/metabolismo , MicroARNs/biosíntesis , Dengue Grave/metabolismo , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
2.
Front Microbiol ; 9: 2811, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30515147

RESUMEN

Currently only four genome sequences for Limnothrix spp. are publicly available, and information on the genetic properties of cyanobacteria belonging to this genus is limited. In this study, we report the draft genome of Limnothrix sp. CACIAM 69d, isolated from the reservoir of a hydroelectric dam located in the Amazon ecosystem, from where cyanobacterial genomic data are still scarce. Comparative genomic analysis of Limnothrix revealed the presence of key enzymes in the cyanobacterial central carbon metabolism and how it is well equipped for environmental sulfur and nitrogen acquisition. Additionally, this work covered the analysis of Limnothrix CRISPR-Cas systems, pathways related to biosynthesis of secondary metabolites and assembly of extracellular polymeric substances and their exportation. A trans-AT PKS gene cluster was identified in two strains, possibly related to the novel toxin Limnothrixin biosynthesis. Overall, the draft genome of Limnothrix sp. CACIAM 69d adds new data to the small Limnothrix genome library and contributes to a growing representativeness of cyanobacterial genomes from the Amazon region. The comparative genomic analysis of Limnothrix made it possible to highlight unique genes for each strain and understand the overall features of their metabolism.

3.
Sci Rep ; 7: 40780, 2017 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-28112162

RESUMEN

Zika virus (ZIKV) has been associated with microcephaly and other brain abnormalities; however, the molecular consequences of ZIKV to human brain development are still not fully understood. Here we describe alterations in human neurospheres derived from induced pluripotent stem (iPS) cells infected with the strain of Zika virus that is circulating in Brazil. Combining proteomics and mRNA transcriptional profiling, over 500 proteins and genes associated with the Brazilian ZIKV infection were found to be differentially expressed. These genes and proteins provide an interactome map, which indicates that ZIKV controls the expression of RNA processing bodies, miRNA biogenesis and splicing factors required for self-replication. It also suggests that impairments in the molecular pathways underpinning cell cycle and neuronal differentiation are caused by ZIKV. These results point to biological mechanisms implicated in brain malformations, which are important to further the understanding of ZIKV infection and can be exploited as therapeutic potential targets to mitigate it.


Asunto(s)
Proteoma , Transcriptoma , Infección por el Virus Zika/genética , Infección por el Virus Zika/metabolismo , Virus Zika/fisiología , Biomarcadores , Ciclo Celular/genética , Genómica/métodos , Humanos , Inmunohistoquímica , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Neuronas/metabolismo , Neuronas/virología , Filogenia , Infección por el Virus Zika/virología
5.
Infect Genet Evol ; 41: 142-145, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27071531

RESUMEN

In May 2015 the first autochthonous Zika virus infection was reported in Brazil. Rapid and urgent measures are needed to contain the ongoing outbreak. Here we report the full-length ZIKV coding sequence from Bahia. Genetic analysis of outbreak sequences will be essential for characterizing the diversity of circulating strains, identifying hotspots of virus transmission and guiding public health control. Rapid and urgent measures are needed to contain the ongoing outbreak.


Asunto(s)
Genoma Viral/genética , Infección por el Virus Zika/virología , Virus Zika/genética , Brasil , Femenino , Humanos , Persona de Mediana Edad , Filogenia
6.
Science ; 352(6283): 345-349, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-27013429

RESUMEN

Brazil has experienced an unprecedented epidemic of Zika virus (ZIKV), with ~30,000 cases reported to date. ZIKV was first detected in Brazil in May 2015, and cases of microcephaly potentially associated with ZIKV infection were identified in November 2015. We performed next-generation sequencing to generate seven Brazilian ZIKV genomes sampled from four self-limited cases, one blood donor, one fatal adult case, and one newborn with microcephaly and congenital malformations. Results of phylogenetic and molecular clock analyses show a single introduction of ZIKV into the Americas, which we estimated to have occurred between May and December 2013, more than 12 months before the detection of ZIKV in Brazil. The estimated date of origin coincides with an increase in air passengers to Brazil from ZIKV-endemic areas, as well as with reported outbreaks in the Pacific Islands. ZIKV genomes from Brazil are phylogenetically interspersed with those from other South American and Caribbean countries. Mapping mutations onto existing structural models revealed the context of viral amino acid changes present in the outbreak lineage; however, no shared amino acid changes were found among the three currently available virus genomes from microcephaly cases. Municipality-level incidence data indicate that reports of suspected microcephaly in Brazil best correlate with ZIKV incidence around week 17 of pregnancy, although this correlation does not demonstrate causation. Our genetic description and analysis of ZIKV isolates in Brazil provide a baseline for future studies of the evolution and molecular epidemiology of this emerging virus in the Americas.


Asunto(s)
Brotes de Enfermedades , Microcefalia/epidemiología , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/virología , Virus Zika/genética , Aedes/virología , Américas/epidemiología , Animales , Femenino , Genoma Viral/genética , Humanos , Incidencia , Insectos Vectores/virología , Microcefalia/virología , Epidemiología Molecular , Datos de Secuencia Molecular , Mutación , Islas del Pacífico/epidemiología , Filogenia , Embarazo , ARN Viral/genética , Análisis de Secuencia de ARN , Viaje , Virus Zika/clasificación , Virus Zika/aislamiento & purificación , Infección por el Virus Zika/transmisión
7.
BMC Med ; 13: 102, 2015 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-25976325

RESUMEN

BACKGROUND: In December 2013, an outbreak of Chikungunya virus (CHIKV) caused by the Asian genotype was notified in the Caribbean. The outbreak has since spread to 38 regions in the Americas. By September 2014, the first autochthonous CHIKV infections were confirmed in Oiapoque, North Brazil, and in Feira de Santana, Northeast Brazil. METHODS: We compiled epidemiological and clinical data on suspected CHIKV cases in Brazil and polymerase-chain-reaction-based diagnostic was conducted on 68 serum samples from patients with symptom onset between April and September 2014. Two imported and four autochthonous cases were selected for virus propagation, RNA isolation, full-length genome sequencing, and phylogenetic analysis. We then followed CDC/PAHO guidelines to estimate the risk of establishment of CHIKV in Brazilian municipalities. RESULTS: We detected 41 CHIKV importations and 27 autochthonous cases in Brazil. Epidemiological and phylogenetic analyses indicated local transmission of the Asian CHIKV genotype in Oiapoque. Unexpectedly, we also discovered that the ECSA genotype is circulating in Feira de Santana. The presumed index case of the ECSA genotype was an individual who had recently returned from Angola and developed symptoms in Feira de Santana. We estimate that, if CHIKV becomes established in Brazil, transmission could occur in 94% of municipalities in the country and provide maps of the risk of importation of each strain of CHIKV in Brazil. CONCLUSIONS: The etiological strains associated with the early-phase CHIKV outbreaks in Brazil belong to the Asian and ECSA genotypes. Continued surveillance and vector mitigation strategies are needed to reduce the future public health impact of CHIKV in the Americas.


Asunto(s)
Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/transmisión , Fiebre Chikungunya/virología , Virus Chikungunya/genética , Adolescente , Adulto , Anciano , Brasil/epidemiología , Niño , Preescolar , Brotes de Enfermedades , Femenino , Genotipo , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Filogenia , Salud Pública , Riesgo , Adulto Joven
8.
Genome Announc ; 2(6)2014 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-25395627

RESUMEN

Nearly complete genome sequences for three ungrouped viruses, Pacui virus (BEAN27326), Rio Preto da Eva virus (BEAR540870), and Tapirape virus (BEAN767592) isolated in the Amazon region are reported here. All three genomic segments (small, medium and large RNA) were recovered and were similar to members of the genus Orthobunyavirus.

9.
Genome Announc ; 2(6)2014 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-25414513

RESUMEN

We report the genome, in a single chromosome, of Lactococcus lactis strain AI06, isolated from the mesocarp of the açaí fruit (Euterpe oleracea) in eastern Amazonia, Brazil. This strain is an endophyte of the açaí palm and also a component of the microbiota of the edible food product.

10.
Genet Mol Biol ; 36(1): 22-7, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23569404

RESUMEN

Soroprevalence for Hepatitis C virus is reported as 2.12% in Northern Brazil, with about 50% of the patients exhibiting a sustained virological response (SVR). Aiming to associate polymorphisms in Killer Cell Immunoglobulin-like Receptors (KIR) with chronic hepatitis C and therapy responses we investigated 125 chronic patients and 345 controls. Additionally, 48 ancestry markers were genotyped to control for population stratification. The frequency of the KIR2DL2 and KIR2DL2+HLA-C(Asp80) gene and ligand was higher in chronic infected patients than in controls (p < 0.0009, OR = 3.4; p = 0.001, OR = 3.45). In fact, KIR2DL3 is a weaker inhibitor of NK activity than KIR2DL2, which could explain the association of KIR2DL2 with chronic infection. Moreover, KIR2DS2 and KIR2DS2+HLA-C(Asp80) (p < 0.0001, OR = 2.51; p = 0.0084, OR = 2.62) and KIR2DS3 (p < 0.0001; OR = 2.57) were associated with chronic infection, independently from KIR2DL2. No differences in ancestry composition were observed between control and patients, even with respect to therapy response groups. The allelic profile KIR2DL2/KIR2DS2/KIR2DS3 was associated with the chronic hepatitis C (p < 0.0001; OR = 3). Furthermore, the patients also showed a higher mean number of activating genes and a lower frequency of the homozygous AA profile, which is likely secondary to the association with non-AA and/or activating genes. In addition, the KIR2DS5 allele was associated with SVR (p = 0.0261; OR = 0.184).The ancestry analysis of samples ruled out any effects of population substructuring and did not evidence interethnic differences in therapy response, as suggested in previous studies.

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