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1.
J Med Virol ; 96(6): e29706, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38888111

RESUMO

The diversity and evolution of the genomes of human bocavirus (HBoV), which causes respiratory diseases, have been scarcely studied. Here, we aimed to obtain and characterize HBoV genomes from patients's nasopharyngeal samples collected between 2017 and 2022 period (5 years and 7 months). Next-generation sequencing (NGS) used Illumina technology after having implemented using GEMI an in-house multiplex PCR amplification strategy. Genomes were assembled and analyzed with CLC Genomics, Mafft, BioEdit, MeV, Nextclade, MEGA, and iTol. A total of 213 genomes were obtained. Phylogeny classified them all as of Bocavirus 1 (HBoV1) species. Five HBoV1 genotypic clusters determined by hierarchical clustering analysis of 27 variable genome positions were scattered over the study period although with differences in yearly prevalence. A total of 167 amino acid substitutions were detected. Besides, coinfection was observed for 52% of the samples, rhinoviruses then adenoviruses (HAdVs) being the most common viruses. Principal component analysis showed that HBoV1 genotypic cluster α tended to be correlated with HAdV co-infection. Subsequent HAdV typing for HBoV1-positive samples and negative controls demonstrated that HAdVC species predominated but HAdVB was that significantly HBoV1-associated. Overall, we described here the first HBoV1 genomes sequenced for France. HBoV1 and HAdVB association deserves further investigation.


Assuntos
Coinfecção , Genoma Viral , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Bocavirus Humano , Infecções por Parvoviridae , Filogenia , Humanos , Bocavirus Humano/genética , Bocavirus Humano/classificação , Bocavirus Humano/isolamento & purificação , Genoma Viral/genética , França/epidemiologia , Infecções por Parvoviridae/virologia , Infecções por Parvoviridae/epidemiologia , Feminino , Pré-Escolar , Masculino , Criança , Adulto , Lactente , Pessoa de Meia-Idade , Coinfecção/virologia , Coinfecção/epidemiologia , Adolescente , Nasofaringe/virologia , Adulto Jovem , Idoso , Análise de Sequência de DNA , Variação Genética , DNA Viral/genética
2.
J Med Virol ; 95(6): e28799, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37342884

RESUMO

A large outbreak of Monkeypox virus (MPXV) infections has arisen in May 2022 in nonendemic countries. Here, we performed DNA metagenomics using next-generation sequencing with Illumina or Nanopore technologies for clinical samples from MPXV-infected patients diagnosed between June and July 2022. Classification of the MPXV genomes and determination of their mutational patterns were performed using Nextclade. Twenty-five samples from 25 patients were studied. A MPXV genome was obtained for 18 patients, essentially from skin lesions and rectal swabbing. All 18 genomes were classified in clade IIb, lineage B.1, and we identified four B.1 sublineages (B.1.1, B.1.10, B.1.12, B.1.14). We detected a high number of mutations (range, 64-73) relatively to a 2018 Nigerian genome (genome GenBank Accession no. NC_063383.1), which were harbored by a large part of a set of 3184 MPXV genomes of lineage B.1 recovered from GenBank and Nextstrain; and we detected 35 mutations relatively to genome ON563414.3 (a B.1 lineage reference genome). Nonsynonymous mutations occurred in genes encoding central proteins, among which transcription factors and core and envelope proteins, and included two mutations that would truncate a RNA polymerase subunit and a phospholipase d-like protein, suggesting an alternative start codon and gene inactivation, respectively. A large majority (94%) of nucleotide substitutions were G > A or C > U, suggesting the action of human APOBEC3 enzymes. Finally, >1000 reads were identified as from Staphylococcus aureus and Streptococcus pyogenes for 3 and 6 samples, respectively. These findings warrant a close genomic monitoring of MPXV to get a better picture of the genetic micro-evolution and mutational patterns of this virus, and a close clinical monitoring of skin bacterial superinfection in monkeypox patients.


Assuntos
Mpox , Superinfecção , Humanos , Monkeypox virus/genética , Genoma Viral , Inativação Gênica , Desaminases APOBEC/genética
3.
J Med Virol ; 95(1): e28102, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36031728

RESUMO

The nature and dynamics of mutations associated with the emergence, spread, and vanishing of SARS-CoV-2 variants causing successive waves are complex. We determined the kinetics of the most common French variant ("Marseille-4") for 10 months since its onset in July 2020. Here, we analyzed and classified into subvariants and lineages 7453 genomes obtained by next-generation sequencing. We identified two subvariants, Marseille-4A, which contains 22 different lineages of at least 50 genomes, and Marseille-4B. Their average lifetime was 4.1 ± 1.4 months, during which 4.1 ± 2.6 mutations accumulated. Growth rate was 0.079 ± 0.045, varying from 0.010 to 0.173. Most of the lineages exhibited a bell-shaped distribution. Several beneficial mutations at unpredicted sites initiated a new outbreak, while the accumulation of other mutations resulted in more viral heterogenicity, increased diversity and vanishing of the lineages. Marseille-4B emerged when the other Marseille-4 lineages vanished. Its ORF8 gene was knocked out by a stop codon, as reported in SARS-CoV-2 of mink and in the Alpha variant. This subvariant was associated with increased hospitalization and death rates, suggesting that ORF8 is a nonvirulence gene. We speculate that the observed heterogenicity of a lineage may predict the end of the outbreak.


Assuntos
COVID-19 , Epidemias , Vírus de RNA , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Filogenia
4.
J Med Virol ; 94(8): 3739-3749, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35467028

RESUMO

Multiple SARS-CoV-2 variants have successively, or concomitantly spread worldwide since the summer of 2020. A few co-infections with different variants were reported and genetic recombinations, common among coronaviruses, were reported or suspected based on co-detection of signature mutations of different variants in a given genome. Here we report three infections in southern France with a Delta 21J_AY.4-Omicron 21K/BA.1 "Deltamicron" recombinant. The hybrid genome harbors signature mutations of the two lineages, supported by a mean sequencing depth of 1163-1421 reads and a mean nucleotide diversity of 0.1%-0.6%. It is composed of the near full-length spike gene (from codons 156-179) of an Omicron 21K/BA.1 variant in a Delta 21J/AY.4 lineage backbone. Importantly, we cultured an isolate of this recombinant and sequenced its genome. It was observed by scanning electron microscopy. As it is misidentified with current variant screening quantitative polymerase chain reaction (qPCR), we designed and implemented for routine diagnosis a specific duplex qPCR. Finally, structural analysis of the recombinant spike suggested its hybrid content could optimize viral binding to the host cell membrane. These findings prompt further studies of the virological, epidemiological, and clinical features of this recombinant.


Assuntos
COVID-19 , SARS-CoV-2 , Sequência de Bases , COVID-19/diagnóstico , Humanos , Filogenia , SARS-CoV-2/genética
5.
Clin Infect Dis ; 73(9): e2571-e2579, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32668457

RESUMO

BACKGROUND: The spectrum of infections caused by methanogens remains to be described. We searched for methanogens in the blood of febrile patients using specific tools. METHODS: Blood culture samples routinely collected in patients with fever were prospectively screened by specific PCR assays for methanogens. Positive samples were observed by autofluorescence and electron microscopy, analyzed by metagenomics and cultured using previously developed methods. Blood culture bottles experimentally inoculated were used as controls. The presence of methanogens in vascular and cardiac tissues was assessed by indirect immunofluorescence, fluorescent in situ hybridization and PCR-based investigations. RESULTS: PCR detection attempted in 7,716 blood samples, was negative in all 1,312 aerobic bottles and 810 bacterial culture-negative anaerobic bottles. PCRs were positive in 27/5,594 (0.5%) bacterial culture-positive anaerobic bottles collected from 26 patients. Sequencing confirmed Methanobrevibacter smithii associated with staphylococci in 14 patients, Enterobacteriaceae in nine patients and streptococci in three patients. Metagenomics confirmed M. smithii in five samples, and M. smithii was isolated in broth from two samples; the genomes of these two isolates were sequenced. Blood cultures experimentally inoculated with Enterobacteriaceae, Staphylococcus epidermidis or Staphylococcus hominis yielded hydrogen, but no methane, authentifying observational data. Three patients diagnosed with infectious mitral endocarditis, were indisputably diagnosed by microscopy, PCR-based detections and culture: we showed M. smithii microscopically and by a specific PCR followed by sequencing method in two of three cardiovascular tissues. CONCLUSIONS: Using appropriate laboratory methods, M. smithii is demonstrated as causing archaemia and endocarditis in febrile patients who are coinfected by bacteria.


Assuntos
Bacteriemia , Endocardite , Bacteriemia/diagnóstico , Humanos , Hibridização in Situ Fluorescente , Metagenômica , Methanobrevibacter/genética
6.
J Clin Microbiol ; 56(10)2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30068538

RESUMO

Routine staining of sputum specimens does not identify acid-fast bacilli as Mycobacterium tuberculosis with utmost precision, limiting its usability as a confirmatory test for pulmonary tuberculosis. We have combined Ziehl-Neelsen staining and fluorescence in situ hybridization (FISH) to detect M. tuberculosis in sputum specimens. We have developed a new fluorescent oligonucleotide rpoBMTC probe (5'-Alexa-555-AGCGGGGTGATGTCAACCCAG-3') targeting the M. tuberculosis complex rpoB gene. In silico alignment yielded 100% match for M. tuberculosis complex mycobacteria, 66.6% to 47.6% for other bacteria, and no significant hits for viruses and eukaryotes. Negative binding of rpoBMTC probe to the top six respiratory tract bacterial pathogens and to Mycobacterium abscessus and Mycobacterium avium experimentally confirmed its specificity. As for sensitivity, rpoBMTC-FISH detected 103 CFU/ml M. tuberculosis as confirmed by successful detection of M. tuberculosis in artificially seeded sputum samples. The application of rpoBMTC-FISH to 116 routine sputum specimens yielded a detection of M. tuberculosis in all of the 31 Ziehl-Neelsen-positive and culture-positive specimens, and no detection of M. tuberculosis in the 85 M. tuberculosis-negative specimens. These data established the proof of concept that rpoBMTC-FISH alone or combined with Ziehl-Neelsen staining can specifically "FISH out" M. tuberculosis complex mycobacteria in sputum samples collected from patients suspected of pulmonary mycobacteriosis. We are implementing this probe for the routine and specific detection of M. tuberculosis complex bacteria in sputum exhibiting acid-fast mycobacteria.


Assuntos
Proteínas de Bactérias/genética , Técnicas Bacteriológicas/métodos , RNA Polimerases Dirigidas por DNA/genética , Hibridização in Situ Fluorescente , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Pulmonar/diagnóstico , Corantes Fluorescentes , Humanos , Microscopia de Fluorescência , Mycobacterium tuberculosis/genética , Sensibilidade e Especificidade , Escarro
8.
Curr Microbiol ; 70(2): 212-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25274413

RESUMO

Tuberculosis (TB) diagnosis in low-income countries is mainly done by microscopy. Hence, little is known about the diversity of Mycobacterium spp. in TB infections. Different genotypes or lineages of Mycobacterium tuberculosis vary in virulence and induce different inflammatory and immune responses. Trained Cricetomys rats show a potential for rapid diagnosis of TB. They detect over 28 % of smear-negative, culture-positive TB. However, it is unknown whether these rats can equally detect sputa from patients infected with different genotypes of M. tuberculosis. A 4-month prospective study on diversity of Mycobacterium spp. was conducted in Dar es Salaam, Tanzania. 252 sputa from 161 subjects were cultured on Lowenstein-Jensen medium and thereafter tested by rats. Mycobacterial isolates were subjected to molecular identification and multispacer sequence typing (MST) to determine species and genotypes. A total of 34 Mycobacterium spp. isolates consisting of 32 M. tuberculosis, 1 M. avium subsp. hominissuis and 1 M. intracellulare were obtained. MST analyses of 26 M. tuberculosis isolates yielded 10 distinct MST genotypes, including 3 new genotypes with two clusters of related patterns not grouped by geographic areas. Genotype MST-67, shared by one-third of M. tuberculosis isolates, was associated with the Mwananyamala clinic. This study shows that diverse M. tuberculosis genotypes (n = 10) occur in Dar es Salaam and trained rats detect 80 % of the genotypes. Sputa with two M. tuberculosis genotypes (20 %), M. avium hominissuis and M. intracellulare were not detected. Therefore, rats detect sputa with different M. tuberculosis genotypes and can be used to detect TB in resource-poor countries.


Assuntos
Genótipo , Mycobacterium/classificação , Mycobacterium/genética , Tuberculose Pulmonar/microbiologia , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Feminino , Geografia Médica , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Filogenia , Estudos Prospectivos , Ratos , Escarro/microbiologia , Tanzânia , Tuberculose Pulmonar/diagnóstico , Adulto Jovem
9.
BMC Pulm Med ; 15: 131, 2015 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-26503635

RESUMO

BACKGROUND: Mycobacterium lentiflavum is rarely isolated in respiratory tract samples from cystic fibrosis patients. We herein describe an unusually high prevalence of M. lentiflavum in such patients. METHODS: M. lentiflavum, isolated from the respiratory tract of cystic fibrosis patients, was identified using both rpoB partial sequencing and detected directly in the sputum by using real-time PCR targeting the smpB gene. RESULTS: M. lentiflavum emerged as the third most prevalent nontuberculous mycobacterial species isolated in cystic fibrosis patients in Marseille, France. Six such patients were all male, and two of them may have fulfilled the American Thoracic Society clinical and microbiological criteria for M. lentiflavum potential lung infection. CONCLUSIONS: M. lentiflavum was the third most common mycobacteria isolated in cystic fibrosis patients, particularly in six male patients. M. lentiflavum outbreaks are emerging particularly in cystic fibrosis patients.


Assuntos
Portador Sadio/epidemiologia , Fibrose Cística/epidemiologia , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Sistema Respiratório/microbiologia , Infecções Respiratórias/epidemiologia , Adolescente , Adulto , Portador Sadio/microbiologia , Fibrose Cística/microbiologia , Feminino , França/epidemiologia , Humanos , Masculino , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/genética , Micobactérias não Tuberculosas/isolamento & purificação , Prevalência , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase em Tempo Real , Infecções Respiratórias/microbiologia , Adulto Jovem
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