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1.
Arch Virol ; 167(11): 2151-2162, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35841448

RESUMO

Arthropod-borne viruses (arboviruses) are a significant public health threat, especially in tropical and subtropical regions. More than 150 arboviruses can cause febrile illness following infection in humans. The Brazilian Amazon region has the highest number of arboviruses detected worldwide. In addition to arboviruses, malaria, caused by Plasmodium vivax, is endemic in the Amazon. Patients with malaria and arboviral disease frequently show similar clinical presentation and laboratory findings, making the diagnosis of the cause of the infection challenging. The aim of this study was to evaluate the potential for viral infections in patients with suspected malaria but without Plasmodium infection in the Brazilian Amazon. We recruited 200 subjects with suspected malaria in Manaus, Brazil. First, we tested for arboviruses in serum samples from 124 of the 200 participants using an arbovirus DNA microarray platform, which did not detect any virus. Then, we mixed the serum samples of the other 76 participants in 10 pools and subjected them to next-generation sequencing. Analysis of the sequencing data revealed the presence of only one arbovirus (Zika virus) in one sample pool. This analysis also detected the presence of primate erythroparvovirus 1 and pegivirus C. These results suggest that arboviruses are not the most frequent viral infections in patients with suspected malaria but without Plasmodium infection in the metropolitan region of Manaus. Implementation of specific viral surveillance tests will help in the early detection of viruses with epidemic potential.


Assuntos
Infecções por Arbovirus , Arbovírus , Malária , Infecção por Zika virus , Zika virus , Animais , Infecções por Arbovirus/diagnóstico , Infecções por Arbovirus/epidemiologia , Arbovírus/genética , Brasil/epidemiologia , Febre , Humanos , Malária/diagnóstico , Malária/epidemiologia , Zika virus/genética
2.
Arch Virol ; 167(9): 1889-1892, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35660981

RESUMO

A new virus, named Mutum virus, related to members of the family Tymoviridae, was isolated from mosquitoes (Mansonia spp.) in clone C6/36 cells, and its complete genome was sequenced. Its genome is 6494 nt in size with an organization resembling that of tymovirids. The isolated virus is phylogenetically related to two viruses isolated from Culex spp. mosquitoes: Ek Balam virus, reported in Mexico, and Culex-originated Tymoviridae-like virus, isolated in China. The results of this study suggest that this virus is a new member of the family Tymoviridae.


Assuntos
Culex , Culicidae , Malvaceae , Tymoviridae , Animais , Brasil , Genoma Viral , Filogenia , Tymoviridae/genética
3.
Clin Infect Dis ; 73(7): e2436-e2443, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32766829

RESUMO

BACKGROUND: Chikungunya virus (CHIKV) emerged in the Americas in 2013 and has caused approximately 2.1 million cases and >600 deaths. A retrospective investigation was undertaken to describe clinical, epidemiological, and viral genomic features associated with deaths caused by CHIKV in Ceará state, northeast Brazil. METHODS: Sera, cerebrospinal fluid (CSF), and tissue samples from 100 fatal cases with suspected arbovirus infection were tested for CHIKV, dengue virus (DENV), and Zika virus (ZIKV). Clinical, epidemiological, and death reports were obtained for patients with confirmed CHIKV infection. Logistic regression analysis was undertaken to identify independent factors associated with risk of death during CHIKV infection. Phylogenetic analysis was conducted using whole genomes from a subset of cases. RESULTS: Sixty-eight fatal cases had CHIKV infection confirmed by reverse-transcription quantitative polymerase chain reaction (52.9%), viral antigen (41.1%), and/or specific immunoglobulin M (63.2%). Co-detection of CHIKV with DENV was found in 22% of fatal cases, ZIKV in 2.9%, and DENV and ZIKV in 1.5%. A total of 39 CHIKV deaths presented with neurological signs and symptoms, and CHIKV-RNA was found in the CSF of 92.3% of these patients. Fatal outcomes were associated with irreversible multiple organ dysfunction syndrome. Patients with diabetes appear to die at a higher frequency during the subacute phase. Genetic analysis showed circulation of 2 CHIKV East-Central-South African (ECSA) lineages in Ceará and revealed no unique virus genomic mutation associated with fatal outcome. CONCLUSIONS: The investigation of the largest cross-sectional cohort of CHIKV deaths to date reveals that CHIKV-ECSA strains can cause death in individuals from both risk and nonrisk groups, including young adults.


Assuntos
Febre de Chikungunya , Vírus da Dengue , Dengue , Infecção por Zika virus , Zika virus , Brasil/epidemiologia , Febre de Chikungunya/epidemiologia , Estudos Transversais , Humanos , Filogenia , Estudos Retrospectivos , Adulto Jovem , Zika virus/genética , Infecção por Zika virus/epidemiologia
4.
Syst Biol ; 68(5): 828-839, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30597118

RESUMO

The International Committee on Taxonomy of Viruses (ICTV) is tasked with classifying viruses into taxa (phyla to species) and devising taxon names. Virus names and virus name abbreviations are currently not within the ICTV's official remit and are not regulated by an official entity. Many scientists, medical/veterinary professionals, and regulatory agencies do not address evolutionary questions nor are they concerned with the hierarchical organization of the viral world, and therefore, have limited use for ICTV-devised taxa. Instead, these professionals look to the ICTV as an expert point source that provides the most current taxonomic affiliations of viruses of interests to facilitate document writing. These needs are currently unmet as an ICTV-supported, easily searchable database that includes all published virus names and abbreviations linked to their taxa is not available. In addition, in stark contrast to other biological taxonomic frameworks, virus taxonomy currently permits individual species to have several members. Consequently, confusion emerges among those who are not aware of the difference between taxa and viruses, and because certain well-known viruses cannot be located in ICTV publications or be linked to their species. In addition, the number of duplicate names and abbreviations has increased dramatically in the literature. To solve this conundrum, the ICTV could mandate listing all viruses of established species and all reported unclassified viruses in forthcoming online ICTV Reports and create a searchable webpage using this information. The International Union of Microbiology Societies could also consider changing the mandate of the ICTV to include the nomenclature of all viruses in addition to taxon considerations. With such a mandate expansion, official virus names and virus name abbreviations could be catalogued and virus nomenclature could be standardized. As a result, the ICTV would become an even more useful resource for all stakeholders in virology.


Assuntos
Classificação/métodos , Virologia/métodos , Vírus/classificação , Cooperação Internacional , Virologia/normas , Virologia/tendências
5.
Virol J ; 17(1): 153, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33054824

RESUMO

BACKGROUND: Human pegivirus (HPgV)-formerly known as GBV-C-is a member of the Flaviviridae family and belongs to the species Pegivirus C. It is a non-pathogenic virus and is transmitted among humans mainly through the exposure to contaminated blood and is often associated with human immunodeficiency virus (HIV) infection, among other viruses. This study aimed to determine the prevalence of HPgV viremia, its association with HIV and clinical epidemiological factors, as well as the full-length sequencing and genome characterization of HPgV recovered from blood donors of the HEMOPA Foundation in Belém-PA-Brazil. METHODS: Plasma samples were obtained from 459 donors, tested for the presence of HPgV RNA by the RT-qPCR. From these, a total of 26 RT-qPCR positive samples were submitted to the NGS sequencing approach in order to obtain the full genome. Genome characterization and phylogenetic analysis were conducted. RESULTS: The prevalence of HPgV was 12.42%. We observed the highest prevalences among donors aged between 18 and 30 years old (16.5%), with brown skin color (13.2%) and men (15.8%). The newly diagnosed HIV-1 prevalence was 26.67%. The HPgV genotype 2 (2a and 2b) was identified. No data on viral load value was found to corroborate the protective effect of HPgV on HIV evolution. CONCLUSIONS: This study provided information regarding the HPgV infection among blood donors from HEMOPA Foundation. Furthermore, we genetically characterized the HPgV circulating strains and described by the first time nearly complete genomes of genotype 2 in Brazilian Amazon.


Assuntos
Doadores de Sangue , Infecções por Flaviviridae/epidemiologia , Vírus GB C/genética , Pegivirus/genética , RNA Viral/sangue , Viremia/epidemiologia , Adolescente , Adulto , Doadores de Sangue/estatística & dados numéricos , Brasil/epidemiologia , Estudos Transversais , Feminino , Infecções por Flaviviridae/virologia , Vírus GB C/classificação , Vírus GB C/isolamento & purificação , Genoma Viral , Genótipo , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pegivirus/classificação , Pegivirus/isolamento & purificação , Filogenia , Prevalência , RNA Viral/genética , Carga Viral , Sequenciamento Completo do Genoma , Adulto Jovem
6.
J Gen Virol ; 100(2): 137-144, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30547856

RESUMO

Triniti virus (TNTV) has been isolated in Trinidad and Tobago and in Brazil. To date little is known about this virus, which is classified as an ungrouped virus within the family Togaviridae. Here, three isolates of TNTV were characterized both genetically and antigenically. The genome was shown to contain three RNA segments: small (S), medium (M) and large (L). Genome organization, protein sizes and protein motifs were similar to those of viruses in the genus Orthobunyavirus, family Peribunyaviridae. Antigenic reactivity revealed the three TNTV isolates to be closely related, but no serologic cross-reaction with other orthobunyaviruses. Morphological observation by transmission electron microscopy indicated that virus size and symmetry were compatible with those of viruses in the family Peribunyaviridae. Our serological, morphological and molecular results support the taxonomic reclassification of TNTV as a member of the genus Orthobunyavirus, family Peribunyaviridae.


Assuntos
Antígenos Virais/imunologia , Orthobunyavirus/classificação , Orthobunyavirus/isolamento & purificação , RNA Viral/genética , Ordem dos Genes , Genoma Viral , Microscopia Eletrônica de Transmissão , Orthobunyavirus/genética , Orthobunyavirus/imunologia , Sorotipagem , Proteínas Virais/análise , Vírion/ultraestrutura
7.
Arch Virol ; 164(3): 927-941, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30663021

RESUMO

In October 2018, the order Bunyavirales was amended by inclusion of the family Arenaviridae, abolishment of three families, creation of three new families, 19 new genera, and 14 new species, and renaming of three genera and 22 species. This article presents the updated taxonomy of the order Bunyavirales as now accepted by the International Committee on Taxonomy of Viruses (ICTV).


Assuntos
Arenaviridae/classificação , Animais , Arenaviridae/genética , Arenaviridae/isolamento & purificação , Infecções por Arenaviridae/virologia , Humanos , Filogenia
8.
J Gen Virol ; 98(4): 585-594, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28141497

RESUMO

The genus Phlebovirus includes the sandfly fever viruses and tick-transmitted uukuviruses. Sandfly fever group viruses have been isolated from various vertebrate species and from phlebotomines and occasionally alternative arthropods, e.g. mosquitoes, or ceratopogonids of the genus Culicoides. Uukuniemi serogroup viruses have been isolated from various vertebrate species and from ticks. Despite the public health importance of some viruses of the genus, the genomic diversity of phleboviruses that could be incriminated as causative of human or veterinary diseases remains underestimated. Here we describe the nearly complete sequences and genomic characterization of two phleboviruses belonging to the Bujaru antigenic complex: the prototype species and the Munguba virus. Furthermore, six previously unclassified phleboviruses isolated in Brazil were also sequenced and characterized: Ambe, Anhanga, Joa, Uriurana, Urucuri and Tapara viruses. The results of the phylogenetic analysis indicated that these viruses group with viruses of three antigenic complexes (Bujaru, Tapara and frijoles clades), with two unclassified phleboviruses. We also performed genomic reassortment analysis and confirmed that there were no events for the viruses described in this study, but we found a new potential reassortment in Medjerda Valley virus, which contains S and L segments of Arbia virus, and probably a unique M segment, both viruses circulate in the same geographic region, indicating these two isolates represent two distinct viruses. This study provides insights into the genetic diversity, classification and evolution of phleboviruses.


Assuntos
Variação Genética , Phlebovirus/classificação , Phlebovirus/isolamento & purificação , Animais , Brasil , Análise por Conglomerados , Genoma Viral , Phlebovirus/genética , Filogenia , Psychodidae/virologia , Vírus Reordenados/genética , Roedores/virologia , Análise de Sequência de DNA , Homologia de Sequência , Xenarthra/virologia
9.
Arch Virol ; 161(8): 2325-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27216928

RESUMO

Piry virus (PIRYV) is a rhabdovirus (genus Vesiculovirus) and is described as a possible human pathogen, originally isolated from a Philander opossum trapped in Para State, Northern Brazil. This study describes the complete full coding sequence and the genetic characterization of PIRYV. The genome sequence reveals that PIRYV has a typical vesiculovirus-like organization, encoding the five genes typical of the genus. Phylogenetic analysis confirmed that PIRYV is most closely related to Perinet virus and clustered in the same clade as Chandipura and Isfahan vesiculoviruses.


Assuntos
Genoma Viral , Vesiculovirus/genética , Sequência de Bases , Genômica , Humanos , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Infecções por Rhabdoviridae/virologia , Vesiculovirus/classificação , Vesiculovirus/isolamento & purificação , Proteínas Virais/genética
10.
BMC Med ; 13: 102, 2015 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-25976325

RESUMO

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.


Assuntos
Febre de Chikungunya/epidemiologia , Febre de Chikungunya/transmissão , Febre de Chikungunya/virologia , Vírus Chikungunya/genética , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Criança , Pré-Escolar , Surtos de Doenças , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Filogenia , Saúde Pública , Risco , Adulto Jovem
11.
Antimicrob Agents Chemother ; 58(5): 2958-60, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24566176

RESUMO

We sequenced the oldest blaKPC-2-bearing plasmid isolated in Brazil and another plasmid also carried by a Klebsiella pneumoniae strain of sequence type 442 (ST442), isolated 52 months later. Both plasmids present an IncN backbone and few acquired regions. Because the 2005 plasmid presented deletions and a truncated gene within Tn4401b compared to the 2009 plasmid, we can thus infer that IncN blaKPC-2-bearing plasmids pFCF1305 and pFCF3SP had a common ancestor circulating in Brazil prior to May 2005.


Assuntos
Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Plasmídeos/genética , Brasil , Farmacorresistência Bacteriana Múltipla/genética , beta-Lactamases/genética
12.
J Genomics ; 12: 47-54, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638167

RESUMO

INTRODUCTION: Metagenomic sequencing is a powerful tool that is widely used in laboratories worldwide for taxonomic characterization of microorganisms in clinical and environmental samples. In this study, we utilized metagenomics to investigate comprehensively the microbial diversity in fecal samples of children over a four-year period. Our methods were carefully designed to ensure accurate and reliable results. MATERIAL AND METHODS: Validated and analyzed were metagenomic data obtained from sequencing 27 fecal samples from children under 10 years old with gastroenteritis over a four-year period (2012-2016). The fecal specimens were collected from patients who received care at public health facilities in the northern region of Brazil. Sequencing libraries were prepared from cDNA and sequenced on the Illumina HiSeq. Kraken-2 was utilized to classify bacterial taxonomy based on the 16S rRNA gene, using the Silva rRNA database. Additionally, the Diamond program was used for mapping to the non-redundant protein database (NR database). Phylogenomic analyses were conducted using Geneious R10 and MEGA X software, and Bayesian estimation of phylogeny was performed using the MrBayes program. The results indicate significant heterogeneity among norovirus strains, with evidence of recombination and point mutations. This study presents the first complete genome of parechovirus 8 in the region. Additionally, it describes the bacterial populations and bacteriophages present in feces, with a high abundance of Firmicutes and Proteobacteria, including an increased proportion of the Enterobacteriaceae family. The presented data demonstrate the genetic diversity of microbial populations and provide a comprehensive report on viral molecular characterization. These findings are relevant for genomic studies in gastrointestinal infections. The metagenomic approach is a powerful tool for investigating microbial diversity in children with gastroenteritis. However, further studies are imperative to conduct genomic analysis of identified bacterial strains and thoroughly analyze antimicrobial resistance genes.

13.
Infect Genet Evol ; 109: 105407, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36764633

RESUMO

The existence of sylvatic transmission of dengue virus in communities of neotropical bats remains uncertain. In this work we present a near-complete genome of dengue virus serotype 4 obtained from the brain sample of a bat from Platyrrhinus helleri specie collected in the Brazilian Amazon region. The presence of the virus in the brain sample may indicate a possible tropism for the central nervous system in bats, which may justify negative results in previous studies that focused on analysis of other tissues, such as liver and spleen. Besides the duration of dengue virus circulation in the Americas (circa 40 years) may be too short for an implementation of a sylvatic dengue virus cycle. Our findings suggest that continued monitoring is needed to confirm with the neotropical bats could potentially act as a natural reservoir of dengue in the region.


Assuntos
Quirópteros , Vírus da Dengue , Dengue , Animais , Vírus da Dengue/genética , Brasil/epidemiologia , Sorogrupo , Encéfalo , Dengue/epidemiologia
14.
Infect Genet Evol ; 113: 105487, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37544570

RESUMO

DENV-2 was the main responsible for a 70% increase in dengue incidence in Brazil during 2019. That year, our metagenomic study by Illumina NextSeq on serum samples from acute febrile patients (n = 92) with suspected arbovirus infection, sampled in 22 cities of the state of Mato Grosso (MT), in the middle west of Brazil, revealed eight complete genomes and two near-complete sequences of DENV-2 genotype III, one Human parvovirus B19 genotype I (5,391 nt) and one Coxsackievirus A6 lineage D (4,514 nt). These DENV-2 sequences share the aminoacidic identities of BR4 lineage on E protein domains I, II and III, and were included in a clade with sequences of the same lineage circulating in the southeast of Brazil in the same year. Nevertheless, 11/34 non-synonymous mutations are unique to three strains inthis study, distributed in the E (n = 6), NS3 (n = 2) and NS5 (n = 3) proteins. Other 14 aa changes on C (n = 1), E (n = 3), NS1 (n = 2), NS2A (n = 1) and NS5 (n = 7) were first reported in a genotype III lineage, having been already reported only in other DENV-2 genotypes. All 10 sequences have mutations in the NS5 protein (14 different aa changes). Nine E protein aa changes found in two sequences, six of which are unique, are in the ectodomain; where the E:M272T change is on the hinge of the E protein at domain II, in a region critical for the anchoring to the host cell receptor. The NS5:G81R mutation, in the methyltransferase domain, was found in one strain of this study. Altogether, these data points to an important evolution of DENV-2 genotype III lineage BR4 during this outbreak in 2019 in MT. Genomic surveillance is essential to detect virus etiology and evolution, possibly related to immune evasion and viral fitness changes leading to future novel outbreaks.


Assuntos
Vírus da Dengue , Dengue , Humanos , Vírus da Dengue/genética , Dengue/epidemiologia , Sorogrupo , Brasil/epidemiologia , Genótipo , Surtos de Doenças , Filogenia
15.
Emerg Infect Dis ; 18(11): 1858-64, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23092706

RESUMO

Dengue virus serotype 4 (DENV-4) reemerged in Roraima State, Brazil, 28 years after it was last detected in the country in 1982. To study the origin and evolution of this reemergence, full-length sequences were obtained for 16 DENV-4 isolates from northern (Roraima, Amazonas, Pará States) and northeastern (Bahia State) Brazil during the 2010 and 2011 dengue virus seasons and for an isolate from the 1982 epidemic in Roraima. Spatiotemporal dynamics of DENV-4 introductions in Brazil were applied to envelope genes and full genomes by using Bayesian phylogeographic analyses. An introduction of genotype I into Brazil from Southeast Asia was confirmed, and full genome phylogeographic analyses revealed multiple introductions of DENV-4 genotype II in Brazil, providing evidence for >3 introductions of this genotype within the last decade: 2 from Venezuela to Roraima and 1 from Colombia to Amazonas. The phylogeographic analysis of full genome data has demonstrated the origins of DENV-4 throughout Brazil.


Assuntos
Vírus da Dengue/genética , Dengue/epidemiologia , Animais , Brasil/epidemiologia , Vírus da Dengue/classificação , Genoma Viral , Genótipo , Humanos , Dados de Sequência Molecular , Filogenia , Filogeografia , Sorotipagem , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética
16.
Mem Inst Oswaldo Cruz ; 107(5): 630-6, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22850953

RESUMO

Rocio virus (ROCV) is an encephalitic flavivirus endemic to Brazil. Experimental flavivirus infections have previously demonstrated a persistent infection and, in this study, we investigated the persistence of ROCV infection in golden hamsters (Mesocricetus auratus). The hamsters were infected intraperitoneally with 9.8 LD50/0.02 mL of ROCV and later anaesthetised and sacrificed at various time points over a 120-day period to collect of blood, urine and organ samples. The viral titres were quantified by real-time-polymerase chain reaction (qRT-PCR). The specimens were used to infect Vero cells and ROCV antigens in the cells were detected by immunefluorescence assay. The levels of antibodies were determined by the haemagglutination inhibition technique. A histopathological examination was performed on the tissues by staining with haematoxylin-eosin and detecting viral antigens by immunohistochemistry (IHC). ROCV induced a strong immune response and was pathogenic in hamsters through neuroinvasion. ROCV was recovered from Vero cells exposed to samples from the viscera, brain, blood, serum and urine and was detected by qRT-PCR in the brain, liver and blood for three months after infection. ROCV induced histopathological changes and the expression of viral antigens, which were detected by IHC in the liver, kidney, lung and brain up to four months after infection. These findings show that ROCV is pathogenic to golden hamsters and has the capacity to cause persistent infection in animals after intraperitoneal infection.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Flavivirus/virologia , Flavivirus/imunologia , Viremia/virologia , Animais , Cricetinae , Modelos Animais de Doenças , Feminino , Infecções por Flavivirus/imunologia , Infecções por Flavivirus/patologia , Técnica Indireta de Fluorescência para Anticorpo , Imuno-Histoquímica , Mesocricetus , RNA Viral/análise , Reação em Cadeia da Polimerase em Tempo Real
17.
Mem Inst Oswaldo Cruz ; 107(8): 1021-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23295753

RESUMO

Because an enriched environment (EE) enhances T-cell activity and T-lymphocytes contribute to immunopathogenesis during heterologous dengue virus (DENV) infections, we hypothesised that an EE increases dengue severity. To compare single serotype (SS) and antibody-enhanced disease (AED) infections regimens, serial intraperitoneal were performed with DENV3 (genotype III) infected brain homogenate or anti-DENV2 hyperimmune serum followed 24 h later by DENV3 (genotype III) infected brain homogenate. Compared AED for which significant differences were detected between the EE and impoverished environmental (IE) groups (Kaplan-Meyer log-rank test, p = 0.0025), no significant differences were detected between the SS experimental groups (Kaplan-Meyer log-rank test, p = 0.089). Survival curves from EE and IE animals infected with the AED regimen were extended after corticoid injection and this effect was greater in the EE than in the IE group (Kaplan-Meyer log-rank test, p = 0.0162). Under the AED regimen the EE group showed more intense clinical signs than the IE group. Dyspnoea, tremor, hunched posture, ruffled fur, immobility, pre-terminal paralysis, shock and death were associated with dominant T-lymphocytic hyperplasia and presence of viral antigens in the liver and lungs. We propose that the increased expansion of these memory T-cells and serotype cross-reactive antibodies facilitates the infection of these cells by DENV and that these events correlate with disease severity in an EE.


Assuntos
Anticorpos Antivirais/imunologia , Anticorpos Facilitadores/imunologia , Vírus da Dengue/imunologia , Dengue/imunologia , Animais , Linfócitos B/imunologia , Dengue/virologia , Ecologia , Feminino , Ativação Linfocitária/imunologia , Camundongos , Linfócitos T/imunologia
18.
J Clin Virol ; 146: 105056, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34923322

RESUMO

BACKGROUND: Neurological viral infection is frequently associated to enterovirus, herpesvirus and arboviruses. These infections may cause severe clinical outcomes, long lasting sequelae or death. Few studies have addressed viral neurological infections etiology in Brazil. OBJECTIVES: Identification of viruses in the cerebral spinal fluid (CSF) of human neurological infections suspected of viral etiology during January and May 2019 in Midwestern Brazil. MATERIALS AND METHODS: Clinical, laboratory and epidemiological information was gathered from medical records. In addition, an aliquot of the sampled CSF was subjected to viral RNA/DNA extraction, randomic dscDNA amplification by PCR, DNA purification and Ilumina HiSeq 2500 sequencing. RESULTS: Six viral genomes belonging to Chikungunya virus (CHIKV) East-Central-South African (ECSA) genotype (10.834-11.804 nt in length) confirmed lately by RT-PCR for CHIKV envelope were present in all six liquor samples. These genomes present two mutations, nsP2:T31I and nsP3:A388V, shared with other Mato Grosso State strains from 2019, not present in sequences of the virus from previous years obtained in the State. One case was a triple co-infection also confirmed through RT-PCR, with Dengue virus serotype 4 genotype II (NS5; 874 nt) and Oropouche virus genotype IA (segment S; 302 nt). CSF was clear and colorless (5/6 patients), with >10% of lymphomononuclear cells (6/6), 1-99 erythrocytes/mm3 (5/6), glucose levels >50 mg/dl (4/5) e > 10 mg/dl of proteins (4/4). One patient evolved to death, and another, a newborn, presented sequelae after recovery. CONCLUSIONS: Despite herpesviruses and enteroviruses are frequent etiologies of neurological infections, the casuistic here reported was associated to arboviruses already known to be responsible for acute febrile illness outbreaks in the state of Mato Grosso, Midwestern Brazil.


Assuntos
Arbovírus , Febre de Chikungunya , Coinfecção , Brasil/epidemiologia , Febre de Chikungunya/complicações , Febre de Chikungunya/epidemiologia , Coinfecção/epidemiologia , Genótipo , Humanos , Filogenia
19.
Virus Res ; 302: 198494, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34174341

RESUMO

Anophelinae is a widely dispersed Culicidae subfamily that may carry a unique virome. Here we herein report the set of viruses found in 323 salivary glands of 16 anopheline species sampled at Upper Pantanal, Chapada dos Guimarães National Park and Coxipó river basin, South Central Mato Grosso, Brazil, pooled (n = 11) and subjected to high throughput sequencing. Metagenomics revealed the presence of nine viral sequences belonging to novel viruses from seven viral families: Purunga is a putative novel orbivirus sharing 74% and 65% aa identity, respectively, with the VP1 and VP3 segments of Changuinola serogroup, Jaracatiá flavivirus shares 60% amino-acid (aa) identity with Aedes flavivirus. Coxipó dielmovirus and Chapada dielmovirus shared 51% and 39% aa identity with Merida virus. Coloiado-orthomyxo like virus is 57.1-64.8% identical at aa level to Aedes albonnulatus orthomyxo-like virus. Mujica picorna-like virus shares 49% aa identity with Flen picorna-like virus and Chiquitos virus is 50% similar to Ista virus, both from Picornavirales order. Cerrado partiti-like-virus shares 75-86% aa identity with Atrato partiti-like virus 2. We also found the S and L segments of Anopheles triannulatus orthophasmavirus (92% identity) in Anopheles lutzi from Chapada dos Guimarães. The identification of these putative novel viruses underscore the wide dispersion of viruses in culicid hosts contributing to extensions on mosquito virome descriptions.


Assuntos
Filogenia , Animais , Brasil , Humanos
20.
Sci Rep ; 11(1): 5554, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33692368

RESUMO

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.


Assuntos
Vírus da Dengue/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Fígado/metabolismo , MicroRNAs/biossíntese , Dengue Grave/metabolismo , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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