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1.
Lancet ; 398(10307): 1217-1229, 2021 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-34534517

RESUMO

BACKGROUND: School-based COVID-19 contacts in England have been asked to self-isolate at home, missing key educational opportunities. We trialled daily testing of contacts as an alternative to assess whether this resulted in similar control of transmission, while allowing more school attendance. METHODS: We did an open-label, cluster-randomised, controlled trial in secondary schools and further education colleges in England. Schools were randomly assigned (1:1) to self-isolation of school-based COVID-19 contacts for 10 days (control) or to voluntary daily lateral flow device (LFD) testing for 7 days with LFD-negative contacts remaining at school (intervention). Randomisation was stratified according to school type and size, presence of a sixth form, presence of residential students, and proportion of students eligible for free school meals. Group assignment was not masked during procedures or analysis. Coprimary outcomes in all students and staff were COVID-19-related school absence and symptomatic PCR-confirmed COVID-19, adjusted for community case rates, to estimate within-school transmission (non-inferiority margin <50% relative increase). Analyses were done on an intention-to-treat basis using quasi-Poisson regression, also estimating complier average causal effects (CACE). This trial is registered with the ISRCTN registry, ISRCTN18100261. FINDINGS: Between March 18 and May 4, 2021, 204 schools were taken through the consent process, during which three decided not to participate further. 201 schools were randomly assigned (control group n=99, intervention group n=102) in the 10-week study (April 19-May 10, 2021), which continued until the pre-appointed stop date (June 27, 2021). 76 control group schools and 86 intervention group schools actively participated; additional national data allowed most non-participating schools to be included in analysis of coprimary outcomes. 2432 (42·4%) of 5763 intervention group contacts participated in daily contact testing. There were 657 symptomatic PCR-confirmed infections during 7 782 537 days-at-risk (59·1 per 100 000 per week) in the control group and 740 during 8 379 749 days-at-risk (61·8 per 100 000 per week) in the intervention group (intention-to-treat adjusted incidence rate ratio [aIRR] 0·96 [95% CI 0·75-1·22]; p=0·72; CACE aIRR 0·86 [0·55-1·34]). Among students and staff, there were 59 422 (1·62%) COVID-19-related absences during 3 659 017 person-school-days in the control group and 51 541 (1·34%) during 3 845 208 person-school-days in the intervention group (intention-to-treat aIRR 0·80 [95% CI 0·54-1·19]; p=0·27; CACE aIRR 0·61 [0·30-1·23]). INTERPRETATION: Daily contact testing of school-based contacts was non-inferior to self-isolation for control of COVID-19 transmission, with similar rates of symptomatic infections among students and staff with both approaches. Infection rates in school-based contacts were low, with very few school contacts testing positive. Daily contact testing should be considered for implementation as a safe alternative to home isolation following school-based exposures. FUNDING: UK Government Department of Health and Social Care.


Assuntos
Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , Controle de Doenças Transmissíveis/métodos , Quarentena/métodos , Instituições Acadêmicas , Adolescente , Adulto , Idoso , COVID-19/prevenção & controle , COVID-19/transmissão , Teste de Ácido Nucleico para COVID-19 , Teste para COVID-19/métodos , Criança , Pessoal de Educação , Inglaterra , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Adulto Jovem
2.
J Clin Microbiol ; 60(4): e0215621, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35354286

RESUMO

Diagnosis of orthopedic device-related infection is challenging, and causative pathogens may be difficult to culture. Metagenomic sequencing can diagnose infections without culture, but attempts to detect antimicrobial resistance (AMR) determinants using metagenomic data have been less successful. Human DNA depletion may maximize the amount of microbial DNA sequence data available for analysis. Human DNA depletion by saponin was tested in 115 sonication fluid samples generated following revision arthroplasty surgery, comprising 67 where pathogens were detected by culture and 48 culture-negative samples. Metagenomic sequencing was performed on the Oxford Nanopore Technologies GridION platform. Filtering thresholds for detection of true species versus contamination or taxonomic misclassification were determined. Mobile and chromosomal genetic AMR determinants were identified in Staphylococcus aureus-positive samples. Of 114 samples generating sequence data, species-level positive percent agreement between metagenomic sequencing and culture was 50/65 (77%; 95% confidence interval [CI], 65 to 86%) and negative percent agreement was 103/114 (90%; 95% CI, 83 to 95%). Saponin treatment reduced the proportion of human bases sequenced in comparison to 5-µm filtration from a median (interquartile range [IQR]) of 98.1% (87.0% to 99.9%) to 11.9% (0.4% to 67.0%), improving reference genome coverage at a 10-fold depth from 18.7% (0.30% to 85.7%) to 84.3% (12.9% to 93.8%). Metagenomic sequencing predicted 13/15 (87%) resistant and 74/74 (100%) susceptible phenotypes where sufficient data were available for analysis. Metagenomic nanopore sequencing coupled with human DNA depletion has the potential to detect AMR in addition to species detection in orthopedic device-related infection. Further work is required to develop pathogen-agnostic human DNA depletion methods, improving AMR determinant detection and allowing its application to other infection types.


Assuntos
Antibacterianos , Saponinas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Metagenoma , Metagenômica/métodos
3.
Clin Infect Dis ; 73(12): 2276-2282, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-33411882

RESUMO

BACKGROUND: The incidence of bloodstream infections (BSIs) caused by Escherichia coli and Klebsiella pneumoniae is increasing, with substantial associated morbidity, mortality, and antimicrobial resistance. Unbiased serotyping studies to guide vaccine target selection are limited. METHODS: We conducted unselected, population-level genomic surveillance of bloodstream E. coli and Klebsiella pneumoniae isolates from 2008 to 2018 in Oxfordshire, United Kingdom. We supplemented this with an analysis of publicly available global sequencing data (n = 3678). RESULTS: We sequenced 3478 E. coli isolates (3278 passed quality control) and 556 K. pneumoniae isolates (535 [K-antigen] and 549 [O-antigen] passed quality control). The 4 most common E. coli O-antigens (O1/O2/O6/O25) were identified in 1499/3278 isolates; the incidence of these O-types increased over time (incidence rate ratio per year [IRRy] = 1.14, 95% confidence interval [CI]: 1.11-1.16). These O-types accounted for 616/1434 multidrug-resistant (MDR) and 173/256 extended-spectrum beta-lactamase (ESBL)-resistant isolates in Oxfordshire but only 19/90 carbapenem-resistant isolates across all studies. For Klebsiella pneumoniae, the most common O-antigens (O2v2/O1v1/O3b/O1v2) accounted for 410/549 isolates; the incidence of BSIs caused by these also increased annually (IRRy = 1.09; 95% CI: 1.05-1.12). These O-types accounted for 122/148 MDR and 106/123 ESBL isolates in Oxfordshire and 557/734 carbapenem-resistant isolates across all studies. Conversely we observed substantial capsular antigen diversity. Analysis of 3678 isolates from global studies demonstrated the generalizability of these findings. For E. coli, based on serotyping, the ExPEC4V and ExPEC10V vaccines under investigation would cover 46% and 72% of Oxfordshire isolates respectively, and 47% and 71% of MDR isolates. CONCLUSIONS: O-antigen targeted vaccines may be useful in reducing the morbidity, mortality, and antimicrobial resistance associated with E. coli and K. pneumoniae BSIs.


Assuntos
Infecções por Escherichia coli , Infecções por Klebsiella , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli , Infecções por Escherichia coli/epidemiologia , Genômica , Humanos , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Sorogrupo , Desenvolvimento de Vacinas , beta-Lactamases/genética
4.
BMC Genomics ; 19(1): 714, 2018 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30261842

RESUMO

BACKGROUND: Prosthetic joint infections are clinically difficult to diagnose and treat. Previously, we demonstrated metagenomic sequencing on an Illumina MiSeq replicates the findings of current gold standard microbiological diagnostic techniques. Nanopore sequencing offers advantages in speed of detection over MiSeq. Here, we report a real-time analytical pathway for Nanopore sequence data, designed for detecting bacterial composition of prosthetic joint infections but potentially useful for any microbial sequencing, and compare detection by direct-from-clinical-sample metagenomic nanopore sequencing with Illumina sequencing and standard microbiological diagnostic techniques. RESULTS: DNA was extracted from the sonication fluids of seven explanted orthopaedic devices, and additionally from two culture negative controls, and was sequenced on the Oxford Nanopore Technologies MinION platform. A specific analysis pipeline was assembled to overcome the challenges of identifying the true infecting pathogen, given high levels of host contamination and unavoidable background lab and kit contamination. The majority of DNA classified (> 90%) was host contamination and discarded. Using negative control filtering thresholds, the species identified corresponded with both routine microbiological diagnosis and MiSeq results. By analysing sequences in real time, causes of infection were robustly detected within minutes from initiation of sequencing. CONCLUSIONS: We demonstrate a novel, scalable pipeline for real-time analysis of MinION sequence data and use of this pipeline to show initial proof of concept that metagenomic MinION sequencing can provide rapid, accurate diagnosis for prosthetic joint infections. The high proportion of human DNA in prosthetic joint infection extracts prevents full genome analysis from complete coverage, and methods to reduce this could increase genome depth and allow antimicrobial resistance profiling. The nine samples sequenced in this pilot study have shown a proof of concept for sequencing and analysis that will enable us to investigate further sequencing to improve specificity and sensitivity.


Assuntos
Bactérias/classificação , Prótese Articular/microbiologia , Metagenômica/métodos , Análise de Sequência de DNA/métodos , Bactérias/genética , Bactérias/isolamento & purificação , DNA Bacteriano/análise , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Nanoporos , Projetos Piloto , Reprodutibilidade dos Testes
5.
J Clin Microbiol ; 56(12)2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30209185

RESUMO

Current guidelines recommend collection of multiple tissue samples for diagnosis of prosthetic joint infections (PJI). Sonication of explanted devices has been proposed as a potentially simpler alternative; however, reported microbiological yield varies. We evaluated sonication for diagnosis of PJI and other orthopedic device-related infections (DRI) at the Oxford Bone Infection Unit between October 2012 and August 2016. We compared the performance of paired tissue and sonication cultures against a "gold standard" of published clinical and composite clinical and microbiological definitions of infection. We analyzed explanted devices and a median of five tissue specimens from 505 procedures. Among clinically infected cases the sensitivity of tissue and sonication culture was 69% (95% confidence interval, 63 to 75) and 57% (50 to 63), respectively (P < 0.0001). Tissue culture was more sensitive than sonication for both PJI and other DRI, irrespective of the infection definition used. Tissue culture yield was higher for all subgroups except less virulent infections, among which tissue and sonication culture yield were similar. The combined sensitivity of tissue and sonication culture was 76% (70 to 81) and increased with the number of tissue specimens obtained. Tissue culture specificity was 97% (94 to 99), compared with 94% (90 to 97) for sonication (P = 0.052) and 93% (89 to 96) for the two methods combined. Tissue culture is more sensitive and may be more specific than sonication for diagnosis of orthopedic DRI in our setting. Variable methodology and case mix may explain reported differences between centers in the relative yield of tissue and sonication culture. Culture yield was highest for both methods combined.


Assuntos
Artrite Infecciosa/diagnóstico , Biópsia , Infecções Relacionadas à Prótese/diagnóstico , Sonicação , Idoso , Artrite Infecciosa/microbiologia , Artrite Infecciosa/patologia , Técnicas Bacteriológicas/normas , Remoção de Dispositivo , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Próteses e Implantes/efeitos adversos , Próteses e Implantes/microbiologia , Infecções Relacionadas à Prótese/microbiologia , Infecções Relacionadas à Prótese/patologia , Sensibilidade e Especificidade , Manejo de Espécimes/normas
6.
J Clin Microbiol ; 55(8): 2334-2347, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28490492

RESUMO

Culture of multiple periprosthetic tissue samples is the current gold standard for microbiological diagnosis of prosthetic joint infections (PJI). Additional diagnostic information may be obtained through culture of sonication fluid from explants. However, current techniques can have relatively low sensitivity, with prior antimicrobial therapy and infection by fastidious organisms influencing results. We assessed if metagenomic sequencing of total DNA extracts obtained direct from sonication fluid can provide an alternative rapid and sensitive tool for diagnosis of PJI. We compared metagenomic sequencing with standard aerobic and anaerobic culture in 97 sonication fluid samples from prosthetic joint and other orthopedic device infections. Reads from Illumina MiSeq sequencing were taxonomically classified using Kraken. Using 50 derivation samples, we determined optimal thresholds for the number and proportion of bacterial reads required to identify an infection and confirmed our findings in 47 independent validation samples. Compared to results from sonication fluid culture, the species-level sensitivity of metagenomic sequencing was 61/69 (88%; 95% confidence interval [CI], 77 to 94%; for derivation samples 35/38 [92%; 95% CI, 79 to 98%]; for validation samples, 26/31 [84%; 95% CI, 66 to 95%]), and genus-level sensitivity was 64/69 (93%; 95% CI, 84 to 98%). Species-level specificity, adjusting for plausible fastidious causes of infection, species found in concurrently obtained tissue samples, and prior antibiotics, was 85/97 (88%; 95% CI, 79 to 93%; for derivation samples, 43/50 [86%; 95% CI, 73 to 94%]; for validation samples, 42/47 [89%; 95% CI, 77 to 96%]). High levels of human DNA contamination were seen despite the use of laboratory methods to remove it. Rigorous laboratory good practice was required to minimize bacterial DNA contamination. We demonstrate that metagenomic sequencing can provide accurate diagnostic information in PJI. Our findings, combined with the increasing availability of portable, random-access sequencing technology, offer the potential to translate metagenomic sequencing into a rapid diagnostic tool in PJI.


Assuntos
Técnicas Bacteriológicas/métodos , Metagenômica/métodos , Técnicas de Diagnóstico Molecular/métodos , Próteses e Implantes/microbiologia , Infecções Relacionadas à Prótese/diagnóstico , Sonicação , Manejo de Espécimes/métodos , Humanos , Sensibilidade e Especificidade , Fatores de Tempo
7.
Pract Midwife ; 17(5): 30-2, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24873115

RESUMO

Yoga is considered a good form of exercise in pregnancy (NHS Choices recommend exercise such as yoga, amongst others) to help women keep fit during their pregnancy and prepare for the birth. But apart from the physical postures, yoga has plenty to offer. The breathing and meditation techniques keep pregnant mothers healthy and relaxed, and provide the mental focus to aid childbirth. In this article we look at yogic breathing and meditation techniques for midwives to recommend to expectant mothers, and some postures that specifically help to encourage an optimal fetal position.


Assuntos
Exercícios Respiratórios , Parto Obstétrico/métodos , Apresentação no Trabalho de Parto , Meditação , Tocologia/métodos , Estresse Psicológico/prevenção & controle , Yoga , Feminino , Humanos , Gravidez
8.
Nat Commun ; 15(1): 1612, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38383544

RESUMO

Plasmids carry genes conferring antimicrobial resistance and other clinically important traits, and contribute to the rapid dissemination of such genes. Previous studies using complete plasmid assemblies, which are essential for reliable inference, have been small and/or limited to plasmids carrying antimicrobial resistance genes (ARGs). In this study, we sequenced 1,880 complete plasmids from 738 isolates from bloodstream infections in Oxfordshire, UK. The bacteria had been originally isolated in 2009 (194 isolates) and 2018 (368 isolates), plus a stratified selection from intervening years (176 isolates). We demonstrate that plasmids are largely, but not entirely, constrained to a single host species, although there is substantial overlap between species of plasmid gene-repertoire. Most ARGs are carried by a relatively small number of plasmid groups with biological features that are predictable. Plasmids carrying ARGs (including those encoding carbapenemases) share a putative 'backbone' of core genes with those carrying no such genes. These findings suggest that future surveillance should, in addition to tracking plasmids currently associated with clinically important genes, focus on identifying and monitoring the dissemination of high-risk plasmid groups with the potential to rapidly acquire and disseminate these genes.


Assuntos
Antibacterianos , Bactérias , Plasmídeos/genética , Bactérias/genética
9.
Clin Infect Dis ; 56(11): 1589-600, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23463640

RESUMO

BACKGROUND: Despite substantial interest in biomarkers, their impact on clinical outcomes and variation with bacterial strain has rarely been explored using integrated databases. METHODS: From September 2006 to May 2011, strains isolated from Clostridium difficile toxin enzyme immunoassay (EIA)-positive fecal samples from Oxfordshire, United Kingdom (approximately 600,000 people) underwent multilocus sequence typing. Fourteen-day mortality and levels of 15 baseline biomarkers were compared between consecutive C. difficile infections (CDIs) from different clades/sequence types (STs) and EIA-negative controls using Cox and normal regression adjusted for demographic/clinical factors. RESULTS: Fourteen-day mortality was 13% in 2222 adults with 2745 EIA-positive samples (median, 78 years) vs 5% in 20,722 adults with 27,550 EIA-negative samples (median, 74 years) (absolute attributable mortality, 7.7%; 95% CI, 6.4%-9.0%). Mortality was highest in clade 5 CDIs (25% [16 of 63]; polymerase chain reaction (PCR) ribotype 078/ST 11), then clade 2 (20% [111 of 560]; 99% PCR ribotype 027/ST 1) versus clade 1 (12% [137 of 1168]; adjusted P < .0001). Within clade 1, 14-day mortality was only 4% (3 of 84) in ST 44 (PCR ribotype 015) (adjusted P = .05 vs other clade 1). Mean baseline neutrophil counts also varied significantly by genotype: 12.4, 11.6, and 9.5 × 10(9) neutrophils/L for clades 5, 2 and 1, respectively, vs 7.0 × 10(9) neutrophils/L in EIA-negative controls (P < .0001) and 7.9 × 10(9) neutrophils/L in ST 44 (P = .08). There were strong associations between C. difficile-type-specific effects on mortality and neutrophil/white cell counts (rho = 0.48), C-reactive-protein (rho = 0.43), eosinophil counts (rho = -0.45), and serum albumin (rho = -0.47). Biomarkers predicted 30%-40% of clade-specific mortality differences. CONCLUSIONS: C. difficile genotype predicts mortality, and excess mortality correlates with genotype-specific changes in biomarkers, strongly implicating inflammatory pathways as a major influence on poor outcome after CDI. PCR ribotype 078/ST 11 (clade 5) leads to severe CDI; thus ongoing surveillance remains essential.


Assuntos
Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/microbiologia , Infecções por Clostridium/mortalidade , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Clostridioides difficile/classificação , Clostridioides difficile/genética , Infecções por Clostridium/epidemiologia , Fezes/microbiologia , Feminino , Genótipo , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Reino Unido/epidemiologia
10.
ACS Nano ; 17(1): 697-710, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36541630

RESUMO

The increasing frequency and magnitude of viral outbreaks in recent decades, epitomized by the COVID-19 pandemic, has resulted in an urgent need for rapid and sensitive diagnostic methods. Here, we present a methodology for virus detection and identification that uses a convolutional neural network to distinguish between microscopy images of fluorescently labeled intact particles of different viruses. Our assay achieves labeling, imaging, and virus identification in less than 5 min and does not require any lysis, purification, or amplification steps. The trained neural network was able to differentiate SARS-CoV-2 from negative clinical samples, as well as from other common respiratory pathogens such as influenza and seasonal human coronaviruses. We were also able to differentiate closely related strains of influenza, as well as SARS-CoV-2 variants. Additional and novel pathogens can easily be incorporated into the test through software updates, offering the potential to rapidly utilize the technology in future infectious disease outbreaks or pandemics. Single-particle imaging combined with deep learning therefore offers a promising alternative to traditional viral diagnostic and genomic sequencing methods and has the potential for significant impact.


Assuntos
COVID-19 , Aprendizado Profundo , Influenza Humana , Humanos , SARS-CoV-2 , COVID-19/diagnóstico por imagem , Pandemias
11.
Microb Genom ; 9(9)2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37676707

RESUMO

Respiratory viral infections are a major global clinical problem, and rapid, cheap, scalable and agnostic diagnostic tests that capture genome-level information on viral variation are urgently needed. Metagenomic approaches would be ideal, but remain currently limited in that much of the genetic content in respiratory samples is human, and amplifying and sequencing the viral/pathogen component in an unbiased manner is challenging. PCR-based tests, including those which detect multiple pathogens, are already widely used, but do not capture information on strain-level variation; tests with larger viral repertoires are also expensive on a per-test basis. One intermediate approach is the use of large panels of viral probes or 'baits', which target or 'capture' sequences representing complete genomes amongst several different common viral pathogens; these are then amplified, sequenced and analysed with a sequence analysis workflow. Here we evaluate one such commercial bait capture method (the Twist Bioscience Respiratory Virus Research Panel) and sequence analysis workflow (OneCodex), using control (simulated) and patient samples head-to-head with a validated multiplex PCR clinical diagnostic test (BioFire FilmArray). We highlight the limited sensitivity and specificity of the joint Twist Bioscience/OneCodex approach, which are further reduced by shortening workflow times and increasing sample throughput to reduce per-sample costs. These issues with performance may be driven by aspects of both the laboratory (e.g. capacity to enrich for viruses present in low numbers), bioinformatics methods used (e.g. a limited viral reference database) and thresholds adopted for calling a virus as present or absent. As a result, this workflow would require further optimization prior to any implementation for respiratory virus characterization in a routine diagnostic healthcare setting.


Assuntos
Biologia Computacional , Hibridização Genética , Humanos , Fluxo de Trabalho , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase Multiplex
12.
Elife ; 122023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36961866

RESUMO

Plasmids enable the dissemination of antimicrobial resistance (AMR) in common Enterobacterales pathogens, representing a major public health challenge. However, the extent of plasmid sharing and evolution between Enterobacterales causing human infections and other niches remains unclear, including the emergence of resistance plasmids. Dense, unselected sampling is essential to developing our understanding of plasmid epidemiology and designing appropriate interventions to limit the emergence and dissemination of plasmid-associated AMR. We established a geographically and temporally restricted collection of human bloodstream infection (BSI)-associated, livestock-associated (cattle, pig, poultry, and sheep faeces, farm soils) and wastewater treatment work (WwTW)-associated (influent, effluent, waterways upstream/downstream of effluent outlets) Enterobacterales. Isolates were collected between 2008 and 2020 from sites <60 km apart in Oxfordshire, UK. Pangenome analysis of plasmid clusters revealed shared 'backbones', with phylogenies suggesting an intertwined ecology where well-conserved plasmid backbones carry diverse accessory functions, including AMR genes. Many plasmid 'backbones' were seen across species and niches, raising the possibility that plasmid movement between these followed by rapid accessory gene change could be relatively common. Overall, the signature of identical plasmid sharing is likely to be a highly transient one, implying that plasmid movement might be occurring at greater rates than previously estimated, raising a challenge for future genomic One Health studies.


Assuntos
Gammaproteobacteria , Sepse , Humanos , Animais , Bovinos , Suínos , Ovinos/genética , Escherichia coli/genética , Gado/genética , Águas Residuárias , Plasmídeos/genética , Klebsiella pneumoniae/genética , Reino Unido , Antibacterianos , beta-Lactamases/genética , Testes de Sensibilidade Microbiana
13.
Commun Biol ; 6(1): 1164, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37964031

RESUMO

The rise of antimicrobial resistance (AMR) is one of the greatest public health challenges, already causing up to 1.2 million deaths annually and rising. Current culture-based turnaround times for bacterial identification in clinical samples and antimicrobial susceptibility testing (AST) are typically 18-24 h. We present a novel proof-of-concept methodological advance in susceptibility testing based on the deep-learning of single-cell specific morphological phenotypes directly associated with antimicrobial susceptibility in Escherichia coli. Our models can reliably (80% single-cell accuracy) classify untreated and treated susceptible cells for a lab-reference fully susceptible E. coli strain, across four antibiotics (ciprofloxacin, gentamicin, rifampicin and co-amoxiclav). For ciprofloxacin, we demonstrate our models reveal significant (p < 0.001) differences between bacterial cell populations affected and unaffected by antibiotic treatment, and show that given treatment with a fixed concentration of 10 mg/L over 30 min these phenotypic effects correlate with clinical susceptibility defined by established clinical breakpoints. Deploying our approach on cell populations from six E. coli strains obtained from human bloodstream infections with varying degrees of ciprofloxacin resistance and treated with a range of ciprofloxacin concentrations, we show single-cell phenotyping has the potential to provide equivalent information to growth-based AST assays, but in as little as 30 min.


Assuntos
Aprendizado Profundo , Infecções por Escherichia coli , Humanos , Escherichia coli/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Escherichia coli/tratamento farmacológico , Ciprofloxacina/farmacologia , Ciprofloxacina/uso terapêutico
14.
PLoS Med ; 9(7): e1001279, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22859914

RESUMO

BACKGROUND: Changing clinical impact, as virulent clones replace less virulent ones, is a feature of many pathogenic bacterial species and can be difficult to detect. Consequently, innovative techniques monitoring infection severity are of potential clinical value. METHODS AND FINDINGS: We studied 5,551 toxin-positive and 20,098 persistently toxin-negative patients tested for Clostridium difficile infection between February 1998 and July 2009 in a group of hospitals based in Oxford, UK, and investigated 28-day mortality and biomarkers of inflammation (blood neutrophil count, urea, and creatinine concentrations) collected at diagnosis using iterative sequential regression (ISR), a novel joinpoint-based regression technique suitable for serial monitoring of continuous or dichotomous outcomes. Among C. difficile toxin-positive patients in the Oxford hospitals, mean neutrophil counts on diagnosis increased from 2003, peaked in 2006-2007, and then declined; 28-day mortality increased from early 2006, peaked in late 2006-2007, and then declined. Molecular typing confirmed these changes were likely due to the ingress of the globally distributed severe C. difficile strain, ST1. We assessed the generalizability of ISR-based severity monitoring in three ways. First, we assessed and found strong (p<0.0001) associations between isolation of the ST1 severe strain and higher neutrophil counts at diagnosis in two unrelated large multi-centre studies, suggesting the technique described might be useful elsewhere. Second, we assessed and found similar trends in a second group of hospitals in Birmingham, UK, from which 5,399 cases were analysed. Third, we used simulation to assess the performance of this surveillance system given the ingress of future severe strains under a variety of assumptions. ISR-based severity monitoring allowed the detection of the severity change years earlier than mortality monitoring. CONCLUSIONS: Automated electronic systems providing early warning of the changing severity of infectious conditions can be established using routinely collected laboratory hospital data. In the settings studied here these systems have higher performance than those monitoring mortality, at least in C. difficile infection. Such systems could have wider applicability for monitoring infections presenting in hospital.


Assuntos
Clostridioides difficile/fisiologia , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/epidemiologia , Laboratórios Hospitalares/estatística & dados numéricos , Vigilância da População , Sistema de Registros/estatística & dados numéricos , Índice de Gravidade de Doença , Idoso , Idoso de 80 Anos ou mais , Clostridioides difficile/patogenicidade , Infecções por Clostridium/mortalidade , Simulação por Computador , Demografia , Feminino , Humanos , Incidência , Masculino , Modelos Biológicos , Neutrófilos/patologia , Análise de Regressão , Reprodutibilidade dos Testes , Estudos Retrospectivos , Reino Unido/epidemiologia , Virulência
15.
Aviat Space Environ Med ; 83(6): 549-55, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22764608

RESUMO

INTRODUCTION: Despite improvement in the computational capabilities of visual displays in flight simulators, intersensory visual-vestibular conflict remains the leading cause of simulator sickness (SS). By using galvanic vestibular stimulation (GVS), the vestibular system can be synchronized with a moving visual field in order to lessen the mismatch of sensory inputs thought to result in SS. METHODS: A multisite electrode array was used to deliver combinations of GVS in 21 normal subjects. Optimal electrode combinations were identified and used to establish GVS dose-response predictions for the perception of roll, pitch, and yaw. Based on these data, an algorithm was then implemented in flight simulator hardware in order to synchronize visual and GVS-induced vestibular sensations (oculo-vestibular-recoupled or OVR simulation). Subjects were then randomly exposed to flight simulation either with or without OVR simulation. A self-report SS checklist was administered to all subjects after each session. An overall SS score was calculated for each category of symptoms for both groups. RESULTS: The analysis of GVS stimulation data yielded six unique combinations of electrode positions inducing motion perceptions in the three rotational axes. This provided the algorithm used for OVR simulation. The overall SS scores for gastrointestinal, central, and peripheral categories were 17%, 22.4%, and 20% for the Control group and 6.3%, 20%, and 8% for the OVR group, respectively. CONCLUSIONS: When virtual head signals produced by GVS are synchronized to the speed and direction of a moving visual field, manifestations of induced SS in a cockpit flight simulator are significantly reduced.


Assuntos
Medicina Aeroespacial , Terapia por Estimulação Elétrica , Enjoo devido ao Movimento/prevenção & controle , Interface Usuário-Computador , Vestíbulo do Labirinto , Adulto , Feminino , Humanos , Masculino , Orientação , Reflexo Vestíbulo-Ocular
16.
J Child Health Care ; 26(4): 648-667, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34372722

RESUMO

The objectives of this review were to identify strategies initiated by parents of children with life-limiting conditions to support their own well-being at home and to describe the impact of these strategies on parental well-being. A systematic scoping review was performed using PRISMA-ScR guidelines, identifying 15 relevant studies that fit the inclusion and exclusion criteria. There were no studies that specifically assessed how parents support their own well-being; however, the 15 identified studies did provide pertinent data secondary to the primary aims of each study. This resulted in the identification of 14 parent-initiated strategies which were grouped thematically into 4 categories: (i) social experience and peer support, (ii) information and management techniques, (iii) reframed perspectives and (iv) prioritising own needs. Overall, there was some evidence of parents initiating specific, individualised and useful strategies to supporting their well-being. Notably lacking was any empirical evaluation as to the effectiveness of these strategies and the wider factors associated with them. Further research is required to assess how parents support their personal well-being in daily life and how these strategies can be implemented alongside service-initiated support to ensure full parental well-being.


Assuntos
Família , Pais , Criança , Humanos , Satisfação Pessoal , Aconselhamento
17.
J Infect ; 84(1): 40-47, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34757137

RESUMO

Objective To describe the impact of the SARS-CoV-2 pandemic on the incidence of paediatric viral respiratory tract infection in Oxfordshire, UK. Methods Data on paediatric Emergency Department (ED) attendances (0-15 years inclusive), respiratory virus testing, vital signs and mortality at Oxford University Hospitals were summarised using descriptive statistics. Results Between 1-March-2016 and 30-July-2021, 155,056 ED attendances occurred and 7,195 respiratory virus PCRs were performed. Detection of all pathogens was suppressed during the first national lockdown. Rhinovirus and adenovirus rates increased when schools reopened September-December 2020, then fell, before rising in March-May 2021. The usual winter RSV peak did not occur in 2020/21, with an inter-seasonal rise (32/1,000 attendances in 0-3 yr olds) in July 2021. Influenza remained suppressed throughout. A higher paediatric early warning score (PEWS) was seen for attendees with adenovirus during the pandemic compared to pre-pandemic (p = 0.04, Mann-Witney U test), no other differences in PEWS were seen. Conclusions SARS-CoV-2 caused major changes in the incidence of paediatric respiratory viral infection in Oxfordshire, with implications for clinical service demand, testing strategies, timing of palivizumab RSV prophylaxis, and highlighting the need to understand which public health interventions are most effective for preventing respiratory virus infections.


Assuntos
COVID-19 , Infecções por Vírus Respiratório Sincicial , Infecções Respiratórias , Criança , Controle de Doenças Transmissíveis , Hospitais de Ensino , Humanos , Pandemias , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções Respiratórias/epidemiologia , SARS-CoV-2 , Reino Unido
18.
Commun Med (Lond) ; 2: 101, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35968045

RESUMO

Background: Gram-negative organisms are common causes of bloodstream infection (BSI) during the neonatal period and early childhood. Whilst several large studies have characterised these isolates in adults, equivalent data (particularly incorporating whole genome sequencing) is lacking in the paediatric population. Methods: We perform an epidemiological and sequencing based analysis of Gram-negative bloodstream infections (327 isolates (296 successfully sequenced) from 287 patients) in children <18 years old between 2008 and 2018 in Oxfordshire, UK. Results: Here we show that the burden of infection lies predominantly in neonates and that most infections are caused by Escherichia coli, Klebsiella spp. and Enterobacter hormaechei. There is no evidence in our setting that the proportion of antimicrobial resistant isolates is increasing in the paediatric population although we identify some evidence of sub-breakpoint increases in gentamicin resistance. The population structure of E. coli BSI isolates in neonates and children mirrors that in adults with a predominance of STs 131/95/73/69 and the same proportions of O-antigen serotypes. In most cases in our setting there is no evidence of transmission/point-source acquisition and we demonstrate the utility of whole genome sequencing to refute a previously suspected outbreak. Conclusions: Our findings support continued use of current empirical treatment guidelines and suggest that O-antigen targeted vaccines may have a role in reducing the incidence of neonatal sepsis.

19.
Aviat Space Environ Med ; 82(5): 518-22, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21614865

RESUMO

BACKGROUND: A few studies in the literature have reported postural changes with hypoxia, but none have quantified the magnitude of change. Further understanding of this condition could have implications for patients at risk for falls, individuals undergoing acute altitude exposure, and pilots and commercial passengers. The objective of this study was to evaluate the effect of different levels of hypoxia (oxygen nitrogen mixtures) on postural standing balance using the computerized dynamic posturography (CDP) system. This improves upon previous protocols by manipulating vision and standing balance with a sway-referenced visual field and/or platform. Additionally, normative data were available for comparison with the cumulative test scores and scores for each condition. METHODS: Altitude hypoxia was simulated by use of admixing nitrogen to the breathing gas to achieve equivalent altitudes of 1524 m, 2438 m, and 3048 m. Subjects were evaluated using the CDP system. RESULTS: Subjects showed an overall trend toward decreased performance at higher simulated altitudes consistent with the initial hypothesis. Composite standing balance sway scores for the sensory organization subtest of CDP were decreased compared to baseline for simulated altitudes as low as 2438 m (mean sway scores: 81.92 at baseline; 81.85 at 1524 m; 79.15 at 2438 m; 79.15 at 3048 m). Reaction times to unexpected movements in the support surface for the motor control subtest (MCT) increased compared to baseline (mean composite scores: 133.3 at baseline; 135.9 ms at 1524 m; 138.0 ms at 2438 m; 140.9 ms at 3048 m). CONCLUSIONS: The CDP testing provided a reliable objective measurement of degradation of balance under hypoxic conditions.


Assuntos
Altitude , Hipóxia/fisiopatologia , Equilíbrio Postural/fisiologia , Adulto , Retroalimentação Sensorial/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
20.
BMJ Open ; 11(11): e048527, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34815274

RESUMO

OBJECTIVES: To inform point-of-care test (POCT) development, we quantified the primary care demand for laboratory microbiology tests by describing their frequencies overall, frequencies of positives, most common organisms identified, temporal trends in testing and patterns of cotesting on the same and subsequent dates. DESIGN: Retrospective cohort study. SETTING: Primary care practices in Oxfordshire. PARTICIPANTS: 393 905 patients (65% female; 49% aged 18-49). PRIMARY AND SECONDARY OUTCOME MEASURES: The frequencies of all microbiology tests requested between 2008 and 2018 were quantified. Patterns of cotesting were investigated with heat maps. All analyses were done overall, by sex and age categories. RESULTS: 1 596 752 microbiology tests were requested. Urine culture±microscopy was the most common of all tests (n=673 612, 42%), was mainly requested without other tests and was the most common test requested in follow-up within 7 and 14 days. Of all urine cultures, 180 047 (27%) were positive and 172 651 (26%) showed mixed growth, and Escherichia coli was the most prevalent organism (132 277, 73% of positive urine cultures). Antenatal urine cultures and blood tests in pregnancy (hepatitis B, HIV and syphilis) formed a common test combination, consistent with their use in antenatal screening. CONCLUSIONS: The greatest burden of microbiology testing in primary care is attributable to urine culture ± microscopy; genital and routine antenatal urine and blood testing are also significant contributors. Further research should focus on the feasibility and impact of POCTs for these specimen types.


Assuntos
Registros Eletrônicos de Saúde , Testes Imediatos , Feminino , Humanos , Masculino , Gravidez , Atenção Primária à Saúde , Estudos Retrospectivos , Reino Unido
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