Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
1.
Euro Surveill ; 24(10)2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30862336

RESUMO

We describe detection in the United Kingdom (UK) of the drug-resistant Neisseria gonorrhoeae FC428 clone, with ceftriaxone resistance and intermediate azithromycin resistance. Two female patients developed infection following contact with UK-resident men from the same sexual network linked to travel to Ibiza, Spain. One case failed treatment with ceftriaxone, and azithromycin and gentamicin, before successful treatment with ertapenem. Both isolates had indistinguishable whole-genome sequences. Urgent action is essential to contain this drug-resistant strain.


Assuntos
Antibacterianos/farmacologia , Azitromicina/uso terapêutico , Ceftriaxona/uso terapêutico , Farmacorresistência Bacteriana/genética , Ertapenem/uso terapêutico , Gonorreia/tratamento farmacológico , Neisseria gonorrhoeae/efeitos dos fármacos , Neisseria gonorrhoeae/genética , Adulto , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Azitromicina/administração & dosagem , Ceftriaxona/administração & dosagem , Ertapenem/administração & dosagem , Feminino , Gonorreia/diagnóstico , Humanos , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae/isolamento & purificação , Polimorfismo de Nucleotídeo Único , Resultado do Tratamento , Reino Unido , Sequenciamento Completo do Genoma
2.
Phys Rev Lett ; 120(9): 095901, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29547334

RESUMO

Heat dissipation in integrated nanoscale devices is a major issue that requires the development of nanoscale temperature probes. Here, we report the implementation of a method that combines electron energy gain and loss spectroscopy to provide a direct measurement of the local temperature in the nanoenvironment. Loss and gain peaks corresponding to an optical-phonon mode in boron nitride were measured from room temperature to ∼1600 K. Both loss and gain peaks exhibit a shift towards lower energies as the sample is heated up. First-principles calculations of the temperature-induced phonon frequency shifts provide insights into the origin of this effect and confirm the experimental data. The experiments and theory presented here open the doors to the study of anharmonic effects in materials by directly probing phonons in the electron microscope.

3.
Epidemiol Infect ; 146(11): 1452-1460, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29961436

RESUMO

Since April 2014 all presumptive Salmonella isolates received by Public Health England (PHE) have been characterised using whole genome sequencing (WGS) and the genomic data generated used to identify clusters of infection. To inform the implementation and development of a national gastrointestinal infection surveillance system based on WGS we have retrospectively identified genetically related clusters of Salmonella Enteritidis and Salmonella Typhimurium infection over a one year period and determined the distribution of these clusters by PHE operational levels. Using a constrained WGS cluster definition based on single nucleotide polymorphism distance, case frequency and temporal spread we demonstrate that the majority of clusters spread to multiple PHE operational levels. The greatest investigative burden is on national level staff investigating small, geographically dispersed clusters. We also demonstrate that WGS identifies long-running, slowly developing clusters that may previously have remained undetected. This analysis also indicates likely increased workload for local health protection teams and will require an operational strategy to balance limited human resources with the public health importance of investigating small, geographically contained clusters of highly related cases. While there are operational challenges to its implementation, integrated cluster detection based on WGS from local to international level will provide further improvements in the identification of, response to and control of clusters of Salmonella spp. with public health significance.


Assuntos
Infecções por Salmonella/epidemiologia , Salmonella enteritidis/isolamento & purificação , Salmonella typhimurium/isolamento & purificação , Sequenciamento Completo do Genoma , Análise por Conglomerados , Inglaterra/epidemiologia , Humanos , Análise Multivariada , Polimorfismo de Nucleotídeo Único , Análise de Regressão , Estudos Retrospectivos , Infecções por Salmonella/microbiologia , Salmonella enteritidis/genética , Salmonella typhimurium/genética
4.
Euro Surveill ; 23(26)2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29970217

RESUMO

Public Health England was alerted to a national outbreak of Shiga toxin-producing Escherichia coli O157 PT34 in July 2016. Early investigations suggested that the likely source was a salad item consumed outside of the home. A number of cases reported consuming meals at a staff canteen (Venue A) and a garden café (Venue B). Both venues shared a common salad supplier. An investigation was undertaken to measure associations between salad items and illness using an 'ingredient-based analysis'. A retrospective case-control study was conducted using an online questionnaire to collect information on menu items consumed at each venue. Chefs at both venues were interviewed to identify ingredients contained within each menu item. Both venues were pooled together for multivariable analysis measuring associations at the ingredient level. Among 203 responses, 24 cases were identified (13 confirmed, two probable and nine possible). Case onsets ranged between 7 and 25 June 2016. Multivariable analysis identified strong evidence that only baby mixed-leaf salad from the common supplier was a vehicle of infection (adjusted odds ratio = 13.1; 95% confidence interval: 1.6-106.5). Identifying the specific salad ingredient associated with illness was made possible by using an ingredient-based analysis. We recommend the increased use of ingredient-based analyses.


Assuntos
Surtos de Doenças , Infecções por Escherichia coli/epidemiologia , Escherichia coli O157/isolamento & purificação , Doenças Transmitidas por Alimentos/epidemiologia , Lactuca/microbiologia , Toxina Shiga/isolamento & purificação , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Pré-Escolar , Surtos de Doenças/estatística & dados numéricos , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/microbiologia , Feminino , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Escherichia coli Shiga Toxigênica/isolamento & purificação , Reino Unido/epidemiologia , Adulto Jovem
5.
Euro Surveill ; 23(18)2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29741151

RESUMO

We investigated a large outbreak of Escherichia coli O157 in the United Kingdom (UK) with 165 cases between 31 May and 29 July 2016. No linked cases were reported in other countries. Cases were predominately female (n = 128) and adult (n = 150), 66 attended hospital and nine had features of haemorrhagic uraemic syndrome. A series of epidemiological studies (case-control, case-case, ingredients-based and venue-based studies) and supply chain investigations implicated mixed salad leaves from Supplier A as the likely outbreak vehicle. Whole genome sequencing (WGS) indicated a link with strains from the Mediterranean and informed the outbreak control team to request that Supplier A cease distributing salad leaves imported from Italy. Microbiological tests of samples of salad leaves from Supplier A were negative. We were unable to confirm the source of contamination or the contaminated constituent leaf although our evidence pointed to red batavia received from Italy as the most likely vehicle. Variations in Shiga toxin-producing E.coli surveillance and diagnosis may have prevented detection of cases outside the UK and highlights a need for greater standardisation. WGS was useful in targeting investigations, but greater coverage across Europe is needed to maximise its potential.


Assuntos
Surtos de Doenças , Infecções por Escherichia coli/epidemiologia , Escherichia coli O157/isolamento & purificação , Doenças Transmitidas por Alimentos/epidemiologia , Genoma Bacteriano/genética , Lactuca/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Adulto , Animais , Estudos de Casos e Controles , DNA Bacteriano/genética , Infecções por Escherichia coli/microbiologia , Escherichia coli O157/genética , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Vigilância de Evento Sentinela , Escherichia coli Shiga Toxigênica/genética , Reino Unido/epidemiologia , Sequenciamento Completo do Genoma
6.
Microsc Microanal ; 20(2): 452-61, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24618013

RESUMO

Insight into dynamic electrochemical processes can be obtained with in situ electrochemical-scanning/transmission electron microscopy (ec-S/TEM), a technique that utilizes microfluidic electrochemical cells to characterize electrochemical processes with S/TEM imaging, diffraction, or spectroscopy. The microfluidic electrochemical cell is composed of microfabricated devices with glassy carbon and platinum microband electrodes in a three-electrode cell configuration. To establish the validity of this method for quantitative in situ electrochemistry research, cyclic voltammetry (CV), choronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) were performed using a standard one electron transfer redox couple [Fe(CN)6]3-/4--based electrolyte. Established relationships of the electrode geometry and microfluidic conditions were fitted with CV and chronoamperometic measurements of analyte diffusion coefficients and were found to agree with well-accepted values that are on the order of 10-5 cm2/s. Influence of the electron beam on electrochemical measurements was found to be negligible during CV scans where the current profile varied only within a few nA with the electron beam on and off, which is well within the hysteresis between multiple CV scans. The combination of experimental results provides a validation that quantitative electrochemistry experiments can be performed with these small-scale microfluidic electrochemical cells provided that accurate geometrical electrode configurations, diffusion boundary layers, and microfluidic conditions are accounted for.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA