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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.
Infect Genet Evol ; 85: 104561, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32961364

RESUMO

Viruses were identified from male anthropophilic mosquitoes from Mato Grosso (MT) State, Midwest Brazil from February 2017 to January 2018. Mosquitoes tested included Aedes (Stegomyia) aegypti (1139 males; 84 pools), Culex quinquefasciatus (9426 males; 179 pools), Culex sp. (3 males; 3 pools) and Psorophora albigenu (1 male; 1 pool) collected from four cities of MT. Pools were subjected to viral RNA extraction followed by RT-PCRs specific for ten flaviviruses, five alphaviruses and Simbu serogroup of orthobunyaviruses. Positive pools were passaged three times in VERO cells (alphavirus and orthobunyavirus) or C6/36 cells (flavivirus), with isolates confirmed through RT-PCR and nucleotide sequencing. We detected pools positive for Ilhéus (1 pool), dengue serotype 4 (1), Mayaro (12), equine encephalitis virus (1) yellow fever (1), Oropouche (2), Zika (4) and chikungunya (12) viruses. High throughput sequencing of arbovirus positive pools identified 35 insect-specific viruses (ISVs) from the families Circoviridae (2), Parvoviridae (2), Totiviridae (1), Flaviviridae (1), Iflaviridae (2), Mesoniviridae (4), Nodaviridae (2), Luteoviridae (1), Phasmaviridae (1) Phenuiviridae (2), Rhabdoviridae (2), Orthomyxoviridae (1), Xinmoviridae (1), and unclassified Bunyavirales (1), unclassified Picornavirales (3), unclassified Riboviria (4) and taxon Negevirus (5). From these, five novel viruses were tentatively named Mojica circovirus, Kuia iflavirus, Muxirum negevirus, Lambada picorna-like virus and Tacuru picorna-like virus. Our findings underscore the diversity and wide geographical distribution of ISVs and arboviruses infecting male culicids.


Assuntos
Arbovírus/fisiologia , Culicidae/virologia , Vírus de Insetos/fisiologia , Animais , Brasil , Linhagem Celular , Chlorocebus aethiops , Sequenciamento de Nucleotídeos em Larga Escala , Vírus de Insetos/classificação , Masculino , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Vero , Tropismo Viral
3.
Front Microbiol ; 11: 1870, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849456

RESUMO

Noroviruses (NoVs) are enteric viruses that cause acute gastroenteritis, and the pandemic GII.4 genotype is spreading and evolving rapidly. The recombinant GII.P16/GII.4_Sydney strain emerged in 2016, replacing GII.P31/GII.4_Sydney (GII.P31 formerly known as GII.Pe) in some countries. We analyzed the complete genome of 20 NoV strains (17 GII.P31/GII.4_ Sydney and 3 GII.P16/GII.4_Sydney) from Belém and Manaus, Brazil, collected from 2012 to 2016. Phylogenetic trees were constructed by maximum likelihood method from 191 full NoV-VP1 sequences, demonstrated segregation of the Sydney lineage in two larger clades, suggesting that GII.4 strains associated with GII.P16 already have modifications compared with GII.P31/GII.4. Additionally, the Bayesian Markov Chain Monte Carlo method was used to reconstruct a time-scaled phylogenetic tree formed by GII.P16 ORF1 sequences (n = 117) and three complete GII.P16 sequences from Belém. The phylogenetic tree indicated the presence of six clades classified into different capsid genotypes and locations. Evolutionary rates of the ORF1 gene of GII.P16 strains was estimated at 2.01 × 10-3 substitutions/site/year, and the most recent common ancestors were estimated in 2011 (2011-2012, 95% HPD). Comparing the amino acid (AA) sequence coding for ORF1 with the prototype strain GII.P16/GII.4, 36 AA changes were observed, mainly in the non-structural proteins p48, p22, and RdRp. GII.P16/GII.4 strains of this study presented changes in amino acids 310, 333, 373, and 393 of the antigenic sites in the P2 subdomain, and ML tree indicating the division within the Sydney lineage according to the GII.P16 and GII.P31 polymerases. Notably, as noroviruses have high recombination rates and the GII.4 genotype was prevalent for a long time in several locations, additional and continuous evolutionary analyses of this new genotype should be needed in the future.

5.
Front Microbiol ; 9: 2811, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30515147

RESUMO

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.

6.
Genome Announc ; 5(28)2017 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-28705982

RESUMO

In order to increase the genomic data of cyanobacterial strains isolated in Brazil, we hereby present the draft genome sequence of the Alkalinema sp. strain CACIAM 70d, isolated from an Amazonian freshwater environment. This report describes the first genome available for this genus.

9.
Genome Announc ; 4(3)2016 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-27198027

RESUMO

Ecological interactions between cyanobacteria and heterotrophic prokaryotes are poorly known. To improve the genomic studies of heterotrophic bacterium-cyanobacterium associations, the draft genome sequence (3.2 Mbp) of Limnobacter sp. strain CACIAM 66H1, found in a nonaxenic culture of Synechococcus sp. (cyanobacteria), is presented here.

11.
Science ; 352(6283): 345-349, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27013429

RESUMO

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.


Assuntos
Surtos de Doenças , Microcefalia/epidemiologia , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/virologia , Zika virus/genética , Aedes/virologia , América/epidemiologia , Animais , Feminino , Genoma Viral/genética , Humanos , Incidência , Insetos Vetores/virologia , Microcefalia/virologia , Epidemiologia Molecular , Dados de Sequência Molecular , Mutação , Ilhas do Pacífico/epidemiologia , Filogenia , Gravidez , RNA Viral/genética , Análise de Sequência de RNA , Viagem , Zika virus/classificação , Zika virus/isolamento & purificação , Infecção por Zika virus/transmissão
12.
Genome Announc ; 2(6)2014 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-25395627

RESUMO

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.

13.
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
14.
PLoS One ; 7(5): e37283, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22662140

RESUMO

The 7th cholera pandemic reached Latin America in 1991, spreading from Peru to virtually all Latin American countries. During the late epidemic period, a strain that failed to ferment sucrose dominated cholera outbreaks in the Northern Brazilian Amazon region. In order to understand the genomic characteristics and the determinants of this altered sucrose fermenting phenotype, the genome of the strain IEC224 was sequenced. This paper reports a broad genomic study of this strain, showing its correlation with the major epidemic lineage. The potentially mobile genomic regions are shown to possess GC content deviation, and harbor the main V. cholera virulence genes. A novel bioinformatic approach was applied in order to identify the putative functions of hypothetical proteins, and was compared with the automatic annotation by RAST. The genome of a large bacteriophage was found to be integrated to the IEC224's alanine aminopeptidase gene. The presence of this phage is shown to be a common characteristic of the El Tor strains from the Latin American epidemic, as well as its putative ancestor from Angola. The defective sucrose fermenting phenotype is shown to be due to a single nucleotide insertion in the V. cholerae sucrose-specific transportation gene. This frame-shift mutation truncated a membrane protein, altering its structural pore-like conformation. Further, the identification of a common bacteriophage reinforces both the monophyletic and African-Origin hypotheses for the main causative agent of the 1991 Latin America cholera epidemics.


Assuntos
Cólera/epidemiologia , Epidemias , Genoma Bacteriano , Sacarose/metabolismo , Vibrio cholerae/genética , Vibrio cholerae/metabolismo , Bacteriófagos/classificação , Bacteriófagos/genética , Composição de Bases , DNA Viral , Sequências Repetitivas Dispersas , América Latina/epidemiologia , Mutação , Fenótipo , Filogenia , Vibrio cholerae/virologia
15.
Hum Immunol ; 70(3): 179-83, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19280715

RESUMO

Idiopathic thrombocytopenic purpura (ITP) is an autoimmune condition with poorly known etiology, characterized by platelet destruction. Genetic association studies of this disease are scarce, discrepant, and restricted to major histocompatibility complex (MHC) polymorphisms. Hence, a case-control study was conducted with an aim to map the MHC to IPT susceptibility using HLA-B and nine microsatellite loci encompassing MHC class I, II, and III regions. We compared the allelic frequencies in samples of unrelated healthy controls and ITP patients. After correction for multiple tests, only allele MICA*183, also known as A5.1, demonstrated an association, resulting in the identification of a major predisposing region close to STR-MICA. This result may highlight the putative functional role of MICA in the immune response to ITP.


Assuntos
Predisposição Genética para Doença , Antígenos HLA-B/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Púrpura Trombocitopênica Idiopática/genética , Púrpura Trombocitopênica Idiopática/imunologia , Adulto , Autoanticorpos , Brasil , Estudos de Casos e Controles , Feminino , Frequência do Gene , Antígenos HLA-B/genética , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Masculino , Repetições de Microssatélites/imunologia , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/imunologia , Complexo Glicoproteico GPIb-IX de Plaquetas/imunologia , Púrpura Trombocitopênica Idiopática/fisiopatologia
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