86 research outputs found
COVID-19: Rapid antigen detection for SARS-CoV-2 by lateral flow assay: A national systematic evaluation of sensitivity and specificity for mass-testing
Background
Lateral flow device (LFD) viral antigen immunoassays have been developed around the world as diagnostic tests for SARS-CoV-2 infection. They have been proposed to deliver an infrastructure-light, cost-economical solution giving results within half an hour.
Methods
LFDs were initially reviewed by a Department of Health and Social Care team, part of the UK government, from which 64 were selected for further evaluation from 1st August to 15th December 2020. Standardised laboratory evaluations, and for those that met the published criteria, field testing in the Falcon-C19 research study and UK pilots were performed (UK COVID-19 testing centres, hospital, schools, armed forces).
Findings
4/64 LFDs so far have desirable performance characteristics (orient Gene, Deepblue, Abbott and Innova SARS-CoV-2 Antigen Rapid Qualitative Test). All these LFDs have a viral antigen detection of >90% at 100,000 RNA copies/ml. 8951 Innova LFD tests were performed with a kit failure rate of 5.6% (502/8951, 95% CI: 5.1–6.1), false positive rate of 0.32% (22/6954, 95% CI: 0.20–0.48). Viral antigen detection/sensitivity across the sampling cohort when performed by laboratory scientists was 78.8% (156/198, 95% CI 72.4–84.3).
Interpretation
Our results suggest LFDs have promising performance characteristics for mass population testing and can be used to identify infectious positive individuals. The Innova LFD shows good viral antigen detection/sensitivity with excellent specificity, although kit failure rates and the impact of training are potential issues. These results support the expanded evaluation of LFDs, and assessment of greater access to testing on COVID-19 transmission.
Funding
Department of Health and Social Care. University of Oxford. Public Health England Porton Down, Manchester University NHS Foundation Trust, National Institute of Health Research
The Cholecystectomy As A Day Case (CAAD) Score: A Validated Score of Preoperative Predictors of Successful Day-Case Cholecystectomy Using the CholeS Data Set
Background
Day-case surgery is associated with significant patient and cost benefits. However, only 43% of cholecystectomy patients are discharged home the same day. One hypothesis is day-case cholecystectomy rates, defined as patients discharged the same day as their operation, may be improved by better assessment of patients using standard preoperative variables.
Methods
Data were extracted from a prospectively collected data set of cholecystectomy patients from 166 UK and Irish hospitals (CholeS). Cholecystectomies performed as elective procedures were divided into main (75%) and validation (25%) data sets. Preoperative predictors were identified, and a risk score of failed day case was devised using multivariate logistic regression. Receiver operating curve analysis was used to validate the score in the validation data set.
Results
Of the 7426 elective cholecystectomies performed, 49% of these were discharged home the same day. Same-day discharge following cholecystectomy was less likely with older patients (OR 0.18, 95% CI 0.15–0.23), higher ASA scores (OR 0.19, 95% CI 0.15–0.23), complicated cholelithiasis (OR 0.38, 95% CI 0.31 to 0.48), male gender (OR 0.66, 95% CI 0.58–0.74), previous acute gallstone-related admissions (OR 0.54, 95% CI 0.48–0.60) and preoperative endoscopic intervention (OR 0.40, 95% CI 0.34–0.47). The CAAD score was developed using these variables. When applied to the validation subgroup, a CAAD score of ≤5 was associated with 80.8% successful day-case cholecystectomy compared with 19.2% associated with a CAAD score >5 (p < 0.001).
Conclusions
The CAAD score which utilises data readily available from clinic letters and electronic sources can predict same-day discharges following cholecystectomy
Whole-genome sequencing reveals host factors underlying critical COVID-19
Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease
Inertial errors of forceplate analysis of artificial turf
Paper examining the inertial errors of forceplate analysis of artificial turf
Player/ground interactions on artificial turf
Paper examining player/ground interactions on artificial turf
Body and limb accelerations during football activities on artificial turf
Paper examining how artificial turf affects body and limb accelerations during football activities
Age estimation and validation for South Pacific albacore Thunnus alalunga
Validated estimates of age are presented for albacore Thunnus alalunga, sampled from a large part of the south-western Pacific Ocean, based on counts of annual opaque growth zones from transverse sections of otoliths. Counts of daily increments were used to estimate the location of the first opaque growth zone, which was completed before the first assumed birthday. The periodicity of opaque zones was estimated by marginal increment analysis and an oxytetracycline mark–recapture experiment. Both validation methods indicated that opaque zones formed over the austral summer and were completed by autumn to winter (April to August). The direct comparison of age estimates obtained from otoliths and dorsal-fin spines of the same fish indicated bias, which was assumed to be due to poor increment clarity and resorption of early growth zones in spines, resulting in imprecise age estimates. As such, age estimates from otoliths are considered to be more accurate than those from spines for T. alalunga. This is consistent with results for a growing number of tropical and temperate tuna Thunnini species. It is recommend that validated counts of annual growth zones from sectioned otoliths is used as the preferred method for estimating age-based parameters for assessment and management advice for these important stocks
Current nematode threats to world agriculture
Many genera and species of nematodes attack almost all crops affecting their yield potential. Their distribution, diversity and potential damage depend on many factors including their centres of origin and subsequent spread, the agroecological conditions and the tolerance and resistance of the crops used in that agricultural system.
A sustainable approach to the control of plant-parasitic nematodes is to prevent their spread on to clean land. Phytosanitary measures are a major strategy to achieve this aim, and their implementation is part of the regulatory system of each country. A history and description of international plant health legislation is given by Hockland et al. (2006). The interception or detection of listed or unlisted quarantine organisms could result in destruction of a shipment or infected crop, or a banning of growing host plants on infested land. In other cases, suppression of the infestation is considered to be a more practical approach that allows trade to continue.
The key nematodes on major world food commodities and their production are discussed in this chapter in addition to the challenges posed by two groups of quarantine nematodes. This information should provide an insight to the problems or potential future problems and the currently known ways to address these
Variations in life history characteristics of the deep-water giant ruby snapper (Etelis sp.) between the Indian and Pacific Oceans and application of a data-poor assessment
The giant ruby snapper, Etelis sp., attains the largest size of any lutjanid in the Indo-Pacific and is one of the most valuable species harvested from deep-water fisheries along the continental and insular shelf margins throughout its broad geographic distribution. Despite this species supporting important commercial, artisanal and subsistence fisheries, quantitative assessments of the status of stocks have been limited by an absence of biological information, unreliable catch and effort statistics, and until recently, misidentification with a cryptic congener. This study aimed, firstly, to describe and compare the age, growth and reproductive characteristics of Etelis sp. between the eastern Indian and western central Pacific Oceans; and secondly, to provide an age-based assessment of the stock in north-western Australia, the only stock for which available data were sufficient to quantify stock status. Although the growth of Etelis sp. differed significantly between sexes and oceans, longevity was similar with a maximum age of 56 years recorded in the Pacific Ocean. Spawning of this species occurred over five months during the austral summer to mid-autumn (i.e. December to April) in the Indian Ocean, but was not well defined in the Pacific Ocean. The estimated ages at 50 % maturity for females and males in the Indian Ocean were similar (i.e. 4–5 years), whereas lengths at 50 % maturity differed ( = 527 and 456 mm fork length, FL, respectively), but were consistent with corresponding differences in growth between sexes. Estimates of the relative female spawning potential ratio for Etelis sp. in north-western Australia suggest the status of this stock remained relatively unchanged from 1997 to 2011, at around 60 % of the unfished level. This assessment provides an example of the relative sustainable exploitation levels for this stock, and potentially other Eteline snappers that exhibit similar life history characteristics, particularly in locations where monitoring and assessments may be data and/or resource limited
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