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1.
J Environ Health ; 80(8): 8-12, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29780175

RESUMO

We investigated an outbreak of eight Legionnaires' disease cases among persons living in an urban residential community of 60,000 people. Possible environmental sources included two active cooling towers (air-conditioning units for large buildings) <1 km from patient residences, a market misting system, a community-wide water system used for heating and cooling, and potable water. To support a timely public health response, we used real-time polymerase chain reaction (PCR) to identify Legionella DNA in environmental samples within hours of specimen collection. We detected L. pneumophila serogroup 1 DNA only at a power plant cooling tower, supporting the decision to order remediation before culture results were available. An isolate from a power plant cooling tower sample was indistinguishable from a patient isolate by pulsed-field gel electrophoresis, suggesting the cooling tower was the outbreak source. PCR results were available <1 day after sample collection, and culture results were available as early as 5 days after plating. PCR is a valuable tool for identifying Legionella DNA in environmental samples in outbreak settings.

2.
Emerg Infect Dis ; 23(11): 1784-1791, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29047425

RESUMO

During the summer of 2015, New York, New York, USA, had one of the largest and deadliest outbreaks of Legionnaires' disease in the history of the United States. A total of 138 cases and 16 deaths were linked to a single cooling tower in the South Bronx. Analysis of environmental samples and clinical isolates showed that sporadic cases of legionellosis before, during, and after the outbreak could be traced to a slowly evolving, single-ancestor strain. Detection of an ostensibly virulent Legionella strain endemic to the Bronx community suggests potential risk for future cases of legionellosis in the area. The genetic homogeneity of the Legionella population in this area might complicate investigations and interpretations of future outbreaks of Legionnaires' disease.


Assuntos
Surtos de Doenças , Legionella pneumophila/isolamento & purificação , Doença dos Legionários/epidemiologia , Doença dos Legionários/microbiologia , Abastecimento de Água , DNA Bacteriano , Microbiologia Ambiental , Genoma Bacteriano , Humanos , Legionella pneumophila/classificação , Legionella pneumophila/patogenicidade , New York/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real , Sequenciamento Completo do Genoma
3.
Emerg Infect Dis ; 23(11)2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29049017

RESUMO

The incidence of Legionnaires' disease in the United States has been increasing since 2000. Outbreaks and clusters are associated with decorative, recreational, domestic, and industrial water systems, with the largest outbreaks being caused by cooling towers. Since 2006, 6 community-associated Legionnaires' disease outbreaks have occurred in New York City, resulting in 213 cases and 18 deaths. Three outbreaks occurred in 2015, including the largest on record (138 cases). Three outbreaks were linked to cooling towers by molecular comparison of human and environmental Legionella isolates, and the sources for the other 3 outbreaks were undetermined. The evolution of investigation methods and lessons learned from these outbreaks prompted enactment of a new comprehensive law governing the operation and maintenance of New York City cooling towers. Ongoing surveillance and program evaluation will determine if enforcement of the new cooling tower law reduces Legionnaires' disease incidence in New York City.


Assuntos
Ar Condicionado/efeitos adversos , Surtos de Doenças , Legionella/isolamento & purificação , Doença dos Legionários/epidemiologia , Microbiologia da Água , Educação Médica Continuada , Humanos , Incidência , Doença dos Legionários/microbiologia , Cidade de Nova Iorque/epidemiologia
4.
Int J Syst Evol Microbiol ; 63(Pt 4): 1323-1328, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22798652

RESUMO

A polyphasic analysis was undertaken of seven independent isolates of gram-negative cocci collected from pathological clinical samples from New York, Louisiana, Florida and Illinois and healthy subgingival plaque from a patient in Virginia, USA. The 16S rRNA gene sequence similarity among these isolates was 99.7-100 %, and the closest species with a validly published name was Neisseria lactamica (96.9 % similarity to the type strain). DNA-DNA hybridization confirmed that these isolates are of the same species and are distinct from their nearest phylogenetic neighbour, N. lactamica. Phylogenetic analysis of 16S and 23S rRNA gene sequences indicated that the novel species belongs in the genus Neisseria. The predominant cellular fatty acids were C16 : 0, summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH) and C18 : 1ω7c. The cellular fatty acid profile, together with other phenotypic characters, further supports the inclusion of the novel species in the genus Neisseria. The name Neisseria oralis sp. nov. (type strain 6332(T)  = DSM 25276(T)  = LMG 26725(T)) is proposed.


Assuntos
Placa Dentária/microbiologia , Gengiva/microbiologia , Neisseria/classificação , Filogenia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/análise , Humanos , Dados de Sequência Molecular , Neisseria/genética , Neisseria/isolamento & purificação , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Análise de Sequência de DNA , Estados Unidos
5.
Mol Cell Probes ; 18(4): 275-82, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15271389

RESUMO

Campylobacter species are the leading agents of bacterial gastroenteritis worldwide. C. jejuni and C. coli together are responsible for more than 95% of all cases of Campylobacter-induced diarrheal disease in the United States. Detection of campylobacteria in clinical samples by conventional culture is problematic and slow due to their complex taxonomy, fastidious growth requirements, and biochemical inertness. The current study describes a rapid, sensitive, and specific real-time polymerase chain reaction (PCR) assay capable of detecting and differentiating C. jejuni (hippuricase gene, hipO) and C. coli (serine hydroxymethyltransferase gene, glyA) in a single reaction, directly from clinical isolates and human feces. The analytical specificity of the assay was demonstrated with a diverse range of Campylobacter species, related organisms, and other diarrhea-inducing bacterial pathogens. The analytical sensitivity of the multiplexed, PCR assay was 10 genome copies for both C. jejuni and C. coli. Following a rapid DNA extraction method (QIAGEN QIAamp DNA stool Mini Kit), the multiplexed PCR identified C. jejuni or C. coli in 100% of fecal samples containing 10(3) colony-forming units (CFU) per gram of feces. This assay represents the first real-time PCR method capable of detecting and differentiating C. jejuni and C. coli in a single reaction.


Assuntos
Campylobacter coli/genética , Campylobacter jejuni/genética , DNA Bacteriano/genética , Fezes/microbiologia , Genes Bacterianos/genética , Sequência de Bases , DNA Bacteriano/isolamento & purificação , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
6.
Biochemistry ; 42(24): 7571-9, 2003 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-12809513

RESUMO

In CV-1 cells transfected with wild-type (wt) nuclear thyroid hormone receptor TRbeta1 (TR), L-thyroxine (T(4)) causes activation and nuclear translocation of mitogen-activated protein kinase (MAPK, ERK1/2), co-immunoprecipitation of MAPK and TR, and MAPK-dependent serine phosphorylation of TR. In the present studies, we have identified (1) the likely site of TR serine phosphorylation in the TR DNA-binding domain (DBD) by T(4)-activated MAPK, (2) the site of MAPK docking on TR induced by T(4), and (3) functional consequences of TR docking site and serine phosphorylation site mutations on co-repressor and co-activator binding and on transcriptional activation by wt and mutant receptors in T(4)-treated cells. Plasmids containing TR(wt), serine 142-substituted TR (TR(S142A) or TR(S142E)), TR(K128A), TR(R132A), or TR(R133A) were transfected into CV-1 cells, and the cells were treated with 10(-7) M T(4) for 30 min. Activated MAPK was present in nuclear fractions of all T(4)-treated cells and co-immunoprecipitated prominently with TR(wt), TR(S142A), and TR(S142E). TR(K128A) complexing with activated MAPK was minimally detectable, but no association of MAPK with TR(R132A) or TR(R133A) was seen in cells treated with T(4). Serine phosphorylation of TR(wt), but not of any mutants, occurred with T(4). In in vitro phosphorylation studies, constitutively activated MAPK phosphorylated only TR(wt). We concluded that serine 142 of the TR DBD is the likely site of phosphorylation by T(4)-activated MAPK and that the docking site on TR for activated MAPK includes residues 128-133 (KGFFRR), a basic amino acid-enriched motif novel for MAPK substrates. TR mutations in the proposed MAPK docking domain and at residue 142 modulated T(4)-conditioned shedding of co-repressor and recruitment of co-activator proteins by the receptor, and they altered transcriptional activity of TR in a thyroid hormone response element-luciferase reporter assay.


Assuntos
Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Receptores beta dos Hormônios Tireóideos/genética , Receptores beta dos Hormônios Tireóideos/metabolismo , Substituição de Aminoácidos , Animais , Sítios de Ligação , Linhagem Celular , Núcleo Celular/metabolismo , Chlorocebus aethiops , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Ativação Enzimática/efeitos dos fármacos , Fosforilação , Testes de Precipitina , Estrutura Terciária de Proteína , Serina/genética , Serina/metabolismo , Receptores beta dos Hormônios Tireóideos/química , Tiroxina/farmacologia , Ativação Transcricional/fisiologia , Transfecção
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