Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Virus Genes ; 53(1): 21-34, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27613417

RESUMO

The complete genomes of a skunkpox, volepox, and raccoonpox virus were sequenced and annotated. Phylogenetic analysis of these genomes indicates that although these viruses are all orthopoxviruses, they form a distinct clade to the other known species. This supports the ancient divergence of the North American orthopoxviruses from other members of the orthopoxviruses. Only two open reading frames appear to be unique to this group of viruses, but a relatively small number of insertions/deletions contribute to the varied gene content of this clade. The availability of these genomes will help determine whether skunkpox and volepox viruses share the characteristics that make raccoonpox a useful vaccine vector.


Assuntos
Genoma Viral , Orthopoxvirus/classificação , Orthopoxvirus/genética , Infecções por Poxviridae/epidemiologia , Infecções por Poxviridae/virologia , Animais , Biologia Computacional/métodos , Regulação Viral da Expressão Gênica , Humanos , Anotação de Sequência Molecular , Mutação , América do Norte/epidemiologia , Fases de Leitura Aberta , Filogenia , Análise de Sequência de DNA
2.
J Infect Dis ; 214(suppl 3): S333-S341, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27521366

RESUMO

BACKGROUND: Several patients with Ebola virus disease (EVD) managed in the United States have received ZMapp monoclonal antibodies, TKM-Ebola small interfering RNA, brincidofovir, and/or convalescent plasma as investigational therapeutics. METHODS: To investigate whether treatment selected for Ebola virus (EBOV) mutations conferring resistance, viral sequencing was performed on RNA extracted from clinical blood specimens from patients with EVD following treatment, and putative viral targets were analyzed. RESULTS: We observed no major or minor EBOV mutations within regions targeted by therapeutics. CONCLUSIONS: This small subset of patients and clinical specimens suggests that evolution of resistance is not a direct consequence of antiviral treatment. As EVD antiviral treatments are introduced into wider use, it is essential that continuous viral full-genome surveillance is performed, to monitor for the emergence of escape mutations.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antivirais/uso terapêutico , Ebolavirus/efeitos dos fármacos , Genoma Viral/genética , Doença pelo Vírus Ebola/tratamento farmacológico , RNA Interferente Pequeno/uso terapêutico , Convalescença , Farmacorresistência Viral , Ebolavirus/genética , Ebolavirus/imunologia , Evolução Molecular , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Epidemiologia Molecular , Mutação , Plasma , Análise de Sequência de DNA
3.
Antimicrob Agents Chemother ; 58(11): 6986-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25199775

RESUMO

Strains of Neisseria gonorrhoeae with mosaic penA genes bearing novel point mutations in penA have been isolated from ceftriaxone treatment failures. Such isolates exhibit significantly higher MIC values to third-generation cephalosporins. Here we report the in vitro isolation of two mutants with elevated MICs to cephalosporins. The first possesses a point mutation in the transpeptidase region of the mosaic penA gene, and the second contains an insertion mutation in pilQ.


Assuntos
Cefalosporinas/farmacologia , Proteínas de Fímbrias/genética , Neisseria gonorrhoeae/efeitos dos fármacos , Neisseria gonorrhoeae/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Eritromicina/farmacologia , Gonorreia/tratamento farmacológico , Gonorreia/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Mutação , Neisseria gonorrhoeae/isolamento & purificação , Proteínas de Ligação às Penicilinas/genética , Falha de Tratamento
4.
Parasitology ; 140(10): 1304-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23863082

RESUMO

Angiostrongylus cantonensis is a parasitic nematode of rodents and a leading aetiological agent of eosinophilic meningitis in humans. Definitive diagnosis is difficult, often relying on immunodiagnostic methods which utilize crude antigens. New immunodiagnostic methods based on recombinant proteins are being developed, and ideally these methods would be made available worldwide. Identification of diagnostic targets, as well as studies on the biology of the parasite, are limited by a lack of molecular information on Angiostrongylus spp. available in databases. In this study we present data collected from DNA random high-throughput sequencing together with proteomic analyses and a cDNA walking methodology to identify and obtain the nucleotide or amino acid sequences of unknown immunoreactive proteins. 28 080 putative ORFs were obtained, of which 3371 had homology to other deposited protein sequences. Using the A. cantonensis genomic sequences, 156 putative ORFs, matching peptide sequences obtained from previous proteomic studies, were considered novel, with no homology to existing sequences. Full-length coding sequences of eight antigenic target proteins were obtained. In this study we generated not only the complete nucleotide sequences of the antigenic protein targets but also a large amount of genomic data which may help facilitate future genomic, proteomic, transcriptomic or metabolomic studies on Angiostrongylus.


Assuntos
Angiostrongylus cantonensis/genética , Genoma Helmíntico/genética , Infecções por Strongylida/parasitologia , Angiostrongylus cantonensis/imunologia , Animais , Proteínas de Helminto/genética , Sequenciamento de Nucleotídeos em Larga Escala , Proteômica , Infecções por Strongylida/imunologia
6.
Antimicrob Agents Chemother ; 54(10): 4314-20, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20660665

RESUMO

Of the 9 vancomycin-resistant Staphylococcus aureus (VRSA) cases reported to date in the literature, 7 occurred in Michigan. In 5 of the 7 Michigan VRSA cases, an Inc18-like vanA plasmid was identified in the VRSA isolate and/or an associated vancomycin-resistant Enterococcus (VRE) isolate from the same patient. This plasmid may play a critical role in the emergence of VRSA. We studied the geographical distribution of the plasmid by testing 1,641 VRE isolates from three separate collections by PCR for plasmid-specific genes traA, repR, and vanA. Isolates from one collection (phase 2) were recovered from surveillance cultures collected in 17 hospitals in 13 states. All VRE isolates from 2 Michigan institutions (n = 386) and between 60 and 70 VRE isolates (n = 883) from the other hospitals were tested. Fifteen VRE isolates (3.9%) from Michigan were positive for an Inc18-like vanA plasmid (9 E. faecalis [12.5%], 3 E. faecium [1.0%], 2 E. avium, and 1 E. raffinosus). Six VRE isolates (0.6%) from outside Michigan were positive (3 E. faecalis [2.7%] and 3 E. faecium [0.4%]). Of all E. faecalis isolates tested, 6.0% were positive for the plasmid, compared to 0.6% for E. faecium and 3.0% for other spp. Fourteen of the 15 plasmid-positive isolates from Michigan had the same Tn1546 insertion site location as the VRSA-associated Inc18-like plasmid, whereas 5 of 6 plasmid-positive isolates from outside Michigan differed in this characteristic. Most plasmid-positive E. faecalis isolates demonstrated diverse patterns by PFGE, with the exception of three pairs with indistinguishable patterns, suggesting that the plasmid is mobile in nature. Although VRE isolates with the VRSA-associated Inc18-like vanA plasmid were more common in Michigan, they remain rare. Periodic surveillance of VRE isolates for the plasmid may be useful in predicting the occurrence of VRSA.


Assuntos
Enterococcus/efeitos dos fármacos , Enterococcus/genética , Plasmídeos/genética , Staphylococcus aureus/genética , Resistência a Vancomicina/genética , Proteínas de Bactérias/genética , Eletroforese em Gel de Campo Pulsado , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Reação em Cadeia da Polimerase , Staphylococcus aureus/efeitos dos fármacos
7.
Microb Genom ; 4(4)2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29616896

RESUMO

Neisseria meningitidis serogroup B (MnB) was responsible for two independent meningococcal disease outbreaks at universities in the USA during 2013. The first at University A in New Jersey included nine confirmed cases reported between March 2013 and March 2014. The second outbreak occurred at University B in California, with four confirmed cases during November 2013. The public health response to these outbreaks included the approval and deployment of a serogroup B meningococcal vaccine that was not yet licensed in the USA. This study investigated the use of whole-genome sequencing(WGS) to examine the genetic profile of the disease-causing outbreak isolates at each university. Comparative WGS revealed differences in evolutionary patterns between the two disease outbreaks. The University A outbreak isolates were very closely related, with differences primarily attributed to single nucleotide polymorphisms/insertion-deletion (SNP/indel) events. In contrast, the University B outbreak isolates segregated into two phylogenetic clades, differing in large part due to recombination events covering extensive regions (>30 kb) of the genome including virulence factors. This high-resolution comparison of two meningococcal disease outbreaks further demonstrates the genetic complexity of meningococcal bacteria as related to evolution and disease virulence.


Assuntos
Surtos de Doenças , Evolução Molecular , Meningite Meningocócica , Neisseria meningitidis Sorogrupo B/genética , Filogenia , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , California/epidemiologia , Feminino , Humanos , Masculino , Meningite Meningocócica/epidemiologia , Meningite Meningocócica/genética , New Jersey/epidemiologia , Universidades
8.
Afr J Lab Med ; 7(1): 708, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29977795

RESUMO

BACKGROUND: Minority drug resistance mutations (DRMs) that are often missed by Sanger sequencing are clinically significant, as they can cause virologic failure in individuals treated with antiretroviral therapy (ART) drugs. OBJECTIVE: This study aimed to estimate the prevalence of minor DRMs among patients enrolled in a Malawi HIV drug resistance monitoring survey at baseline and at one year after initiation of ART. METHODS: Forty-one plasma specimens collected from HIV-1 subtype C-positive patients and seven clonal control samples were analysed using ultra-deep sequencing technology. RESULTS: Deep sequencing identified all 72 DRMs detected by Sanger sequencing at the level of ≥20% and 79 additional minority DRMs at the level of < 20% from the 41 Malawian clinical specimens. Overall, DRMs were detected in 85% of pre-ART and 90.5% of virologic failure patients by deep sequencing. Among pre-ART patients, deep sequencing identified a statistically significant higher prevalence of DRMs to nucleoside reverse transcriptase inhibitors (NRTIs) compared with Sanger sequencing. The difference was mainly due to the high prevalence of minority K65R and M184I mutations. Most virologic failure patients harboured DRMs against both NRTIs and non-nucleoside reverse transcriptase inhibitors (NNRTIs). These minority DRMs contributed to the increased or enhanced virologic failures in these patients. CONCLUSION: The results revealed the presence of minority DRMs to NRTIs and NNRTIs in specimens collected at baseline and virologic failure time points. These minority DRMs not only increased resistance levels to NRTIs and NNRTIs for the prescribed ART, but also expanded resistance to additional major first-line ART drugs. This study suggested that drug resistance testing that uses more sensitive technologies, is needed in this setting.

9.
Genome Announc ; 4(3)2016 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-27340056

RESUMO

Here, we report the 187.8-kb genome sequence of Vaccinia virus Lister-Butantan, which was used in Brazil during the WHO smallpox eradication campaign. Its genome showed an average similarity of 98.18% with the original Lister isolate, highlighting the low divergence among related Vaccinia virus vaccine strains, even after several passages in animals and cell culture.

11.
Genome Announc ; 3(1)2015 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-25573935

RESUMO

Legionella pneumophila is the leading etiology of legionellosis infections in North America and Europe. Here we report the draft genome sequence of L. pneumophila D-5864, a serogroup 6 strain, which was isolated from a bronchial alveolar lavage specimen of a male patient from Arizona in 2009. Genes within the lipopolysaccharide (LPS)-biosynthesis region could potentially be determinants of serogroup specificity.

12.
Genome Announc ; 2(4)2014 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-25013133

RESUMO

Shiga toxin-producing Escherichia coli (STEC) is an important food-borne pathogen. Here, we report the draft whole-genome sequences of nine STEC strains isolated from clinical cases in the United States. This is the first report of such information for STEC of serotypes O69, H11, O145:H25, O118:H16, O91:H21, O146:H21, O45:H2, O128:H2, and O121:H19.

13.
mBio ; 4(4)2013 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-23820394

RESUMO

UNLABELLED: Prior to the epidemic that emerged in Haiti in October of 2010, cholera had not been documented in this country. After its introduction, a strain of Vibrio cholerae O1 spread rapidly throughout Haiti, where it caused over 600,000 cases of disease and >7,500 deaths in the first two years of the epidemic. We applied whole-genome sequencing to a temporal series of V. cholerae isolates from Haiti to gain insight into the mode and tempo of evolution in this isolated population of V. cholerae O1. Phylogenetic and Bayesian analyses supported the hypothesis that all isolates in the sample set diverged from a common ancestor within a time frame that is consistent with epidemiological observations. A pangenome analysis showed nearly homogeneous genomic content, with no evidence of gene acquisition among Haiti isolates. Nine nearly closed genomes assembled from continuous-long-read data showed evidence of genome rearrangements and supported the observation of no gene acquisition among isolates. Thus, intrinsic mutational processes can account for virtually all of the observed genetic polymorphism, with no demonstrable contribution from horizontal gene transfer (HGT). Consistent with this, the 12 Haiti isolates tested by laboratory HGT assays were severely impaired for transformation, although unlike previously characterized noncompetent V. cholerae isolates, each expressed hapR and possessed a functional quorum-sensing system. Continued monitoring of V. cholerae in Haiti will illuminate the processes influencing the origin and fate of genome variants, which will facilitate interpretation of genetic variation in future epidemics. IMPORTANCE: Vibrio cholerae is the cause of substantial morbidity and mortality worldwide, with over three million cases of disease each year. An understanding of the mode and rate of evolutionary change is critical for proper interpretation of genome sequence data and attribution of outbreak sources. The Haiti epidemic provides an unprecedented opportunity to study an isolated, single-source outbreak of Vibrio cholerae O1 over an established time frame. By using multiple approaches to assay genetic variation, we found no evidence that the Haiti strain has acquired any genes by horizontal gene transfer, an observation that led us to discover that it is also poorly transformable. We have found no evidence that environmental strains have played a role in the evolution of the outbreak strain.


Assuntos
Cólera/epidemiologia , Cólera/microbiologia , Epidemias , Evolução Molecular , Genoma Bacteriano , Vibrio cholerae O1/genética , Vibrio cholerae O1/isolamento & purificação , DNA Bacteriano/química , DNA Bacteriano/genética , Ordem dos Genes , Haiti/epidemiologia , Humanos , Mutação , Análise de Sequência de DNA , Vibrio cholerae O1/classificação
14.
Virology ; 422(1): 1-5, 2012 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-21962764

RESUMO

In October and November 2010, hospitals in northern Uganda reported patients with suspected hemorrhagic fevers. Initial tests for Ebola viruses, Marburg virus, Rift Valley fever virus, and Crimean Congo hemorrhagic fever virus were negative. Unbiased PCR amplification of total RNA extracted directly from patient sera and next generation sequencing resulted in detection of yellow fever virus and generation of 98% of the virus genome sequence. This finding demonstrated the utility of next generation sequencing and a metagenomic approach to identify an etiological agent and direct the response to a disease outbreak.


Assuntos
Genoma Viral , RNA Viral/sangue , Febre Amarela/diagnóstico , Vírus da Febre Amarela/genética , Vírus da Febre Amarela/isolamento & purificação , Sequência de Bases , DNA Complementar , Frequência do Gene , Humanos , Técnicas de Diagnóstico Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de RNA , Uganda , Febre Amarela/virologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA