44 research outputs found

    Investigation of molecular mechanisms underlying tetracycline resistance in thermophilic Campylobacter spp. suggests that previous reports of tet(A)-mediated resistance in these bacteria are premature

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    peer-reviewedThe true prevalence of tet(A), which codes for a tetracycline efflux pump, in thermophilic Camplyobacter spp. requires clarification after reports emerged in Iran (2014) and Kenya (2016) of the novel detection of tet(A) in Campylobacter. During our investigation of antibiotic resistance mechanisms in a sample of Irish thermophilic Campylobacter broiler isolates, it was determined that 100% of tetracycline-resistant isolates (n = 119) harboured tet(O). Accessory tetracycline-resistance mechanisms were considered as tetracycline minimum inhibitory concentrations ranged from 4 to ≥ 64 mg/L. Primers previously reported for the detection of tet(A) in Campylobacter failed to produce an amplicon using a positive control strain (Escherichia coli K12 SK1592 containing the pBR322 plasmid) and a selection of Campylobacter isolates. Accordingly, we designed new tet(A)-targeting primers on SnapGene2.3.2 that successfully generated a 407 bp product from the positive control strain only. Further in silico analysis using BLASTn and SnapGene2.3.2 revealed that previously reported Campylobacter tet(A) sequences deposited on GenBank shared 100% homology with Campylobacter tet(O). We postulate that this gave rise to the erroneous report of a high tet(A) prevalence among a pool of Kenyan broiler Campylobacter isolates that were tested using primers designed based on these apparent tet(A) sequences. In conclusion, further work would be required to determine whether the homology between tet(A) potentially present in Campylobacter and known tet(A) genes would be sufficient to allow amplification using the primers designed in our study. Finally, the existence of tet(A) in thermophilic Campylobacter spp. remains to be demonstrated

    Antimicrobial Resistance Determinants Circulating among Thermophilic Campylobacter Isolates Recovered from Broilers in Ireland Over a One-Year Period

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    peer-reviewedCampylobacteriosis is the leading cause of human bacterial gastroenteritis, very often associated with poultry consumption. Thermophilic Campylobacter (Campylobacter jejuni and Campylobacter coli) isolates (n = 158) recovered from broiler neck skin and caecal contents in Ireland over a one-year period, resistant to at least one of three clinically relevant antimicrobial classes, were screened for resistance determinants. All ciprofloxacin-resistant isolates (n = 99) harboured the C257T nucleotide mutation (conferring the Thr-86-Ile substitution) in conjunction with other synonymous and nonsynonymous mutations, which may have epidemiological value. The A2075G nucleotide mutation and amino acid substitutions in L4 and L22 were detected in all erythromycin-resistant isolates (n = 5). The tetO gene was detected in 100% (n = 119) of tetracycline-resistant isolates and three of which were found to harbour the mosaic tetracycline resistance gene tetO/32/O. Two streptomycin-resistant C. jejuni isolates (isolated from the same flock) harboured ant(6)-Ib, located in a multidrug resistance genomic island, containing aminoglycoside, streptothricin (satA) and tetracycline resistance genes (truncated tetO and mosaic tetO/32/O). The ant(6)-Ie gene was identified in two streptomycin-resistant C. coli isolates. This study highlights the widespread acquisition of antimicrobial resistance determinants among chicken-associated Campylobacter isolates, through horizontal gene transfer or clonal expansion of resistant lineages. The stability of such resistance determinants is compounded by the fluidity of mobile genetic element

    Testing barrier materials in the development of a biosecurity pen to protect broilers against Campylobacter

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    peer-reviewedPrevious studies demonstrated that commercial broiler flocks could be protected from Campylobacter colonisation using a bird pen, termed the “biosecurity cube”, constructed from four polycarbonate sheets (1m high x 2.5m long x 6 mm thick) supported at the corners by 4 × 1m high wooden columns. However, this design had issues with airflow and potential for upscaling. A biosecurity cube composed of four galvanised steel mesh panels (3.44m long x 1.25m high) was therefore developed onto which different barrier materials, preventing contact between the test birds and the main flock, were attached. The objective of this study was to test a range of barrier materials including cardboard, wire mesh, polyurethane film and later (at the suggestion of broiler industry personnel) flyscreen mesh. Initial studies suggested that while the cardboard and wire mesh were ineffective, the polyurethane film protected the birds. Further validation (over 2 separate trials, 7 cubes for each barrier material) demonstrated that polyurethane and flyscreen mesh were effective. It was concluded that a biosecurity pen infrastructure based on galvanised steel mesh panels surrounded by polyurethane film or flyscreen mesh was effective at protecting the birds from Campylobacter but upscaling studies will be undertaken before full implementation

    The impact of key processing stages and flock variables on the prevalence and levels of Campylobacter on broiler carcasses

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    peer-reviewedThis study examined the impact of key processing stages and flock variables on the prevalence of Campylobacter on broiler carcasses. Overall, the prevalence of Campylobacter was 62% in caeca, and 68%, 65% and 62% in neck skin samples collected after evisceration, final wash and carcass chilling, respectively. Campylobacter were found in 32% of caeca, and 52%, 40% and 32% of neck skin samples collected after evisceration, final wash and carcass chilling, respectively from first thin broiler batches. Final thin broiler batches were more frequently contaminated with prevalences of 83% found in caeca, 80% in neck skin samples collected after evisceration and 83% found in neck skin samples collected after both final wash and carcass chilling stages (p < 0.05). Thinning status had a significant effect on Campylobacter counts with significantly higher counts observed in samples from final thin batches (p < 0.05). Highest Campylobacter concentrations in neck skin samples were observed at the evisceration stage in both first and final thin samples, with counts ranging from 2.0 to 3.8 log10 CFU/g and 2.3 to 4.8 log10 CFU/g in first and final thin batches, respectively. All first thin samples had counts below the European Union (EU) Process Hygiene Criterion threshold level of 3 log10 CFU/g after chilling while 52% of final thin batches had counts above this limit.Food Institute Research Measur

    Prevalence and levels of Campylobacter in broiler chicken batches and carcasses in Ireland in 2017–2018

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    peer-reviewedIn 2008, an EU wide baseline survey of broilers revealed a high Campylobacter prevalence. To assist with industry-wide controls, updated data were required. The primary objective of this study was to establish up-to-date data on Campylobacter carriage and carcass contamination in Irish broilers. Monthly samples were collected from the three largest broiler processing plants in Ireland over a twelve-month period. Samples were taken from both first and final thin birds (partial and full depopulation) from 358 batches of broilers. From each batch, a composite sample of 10 caecal contents (n = 358) and 5 neck skins (n = 1790) were collected and numbers of Campylobacter in each sample were determined. Of the 1790 neck skin samples tested, 53% were Campylobacter positive. Campylobacter was detected in the caecal contents of 66% of all batches tested. Depopulation and/or age had a significant effect on Campylobacter prevalence with 67% of final thin broilers yielding Campylobacter-positive neck skin samples in contrast to 38% of first thin broilers that yielded positive neck skin samples (P ≤ 0.002). A significant seasonal variation was observed in the rate of Campylobacter-positive caecal samples with higher prevalence seen in July (85%) than the colder months of November (61%), December (50%), January (61%) March (57%) and April (59%). Neck skin samples were 7 times more likely to be Campylobacter positive if the caecal contents from the same batch were positive (odds ratio = 7.1; P ≤ 0.0001). The decrease in Campylobacter prevalence observed in neck skin and caecal contents demonstrates the improvements and progress made in reducing prevalences of this important enteropathogen in the Irish poultry industry since the 2008 EU baseline survey. It also provides further supporting data on the impact of thinning, the processing environment and season on Campylobacter prevalence

    A Reappraisal of Children’s ‘Potential’

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    What does it mean for a child to fulfil his or her potential? This article explores the contexts and implications of the much-used concept of potential in educational discourses. We claim that many of the popular, political and educational uses of the term in relation to childhood have a problematic blind spot: interpersonality, and the necessary coexistence for the concept to be receivable of all children’s ‘potentials’. Rather than advocating abandoning the term—a futile gesture given its emotive force—we argue that the concept of children’s potential must be profoundly rethought to be workable as a philosophical notion in education. In an era marked by the unspoken assumption that ‘unlimited potential’ is always a good thing, we argue that it might be necessary to think about the limitations of the notion of individual potential; namely, the moment when it comes into contact with other people’s projects. We propose a conceptualisation of potential as the negotiated, situated, ever-changing creation of a group of individuals, in a process marked by conflict, and which remains essentially difficult.This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s11217-016-9508-

    Overwintering individuals of the Arctic krill Thysanoessa inermis appear tolerant to short-term exposure to low pH conditions

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    Areas of the Arctic Ocean are already experiencing seasonal variation in low pH/elevated pCO2 and are predicted to be the most affected by future ocean acidification (OA). Krill play a fundamental ecological role within Arctic ecosystems, serving as a vital link in the transfer of energy from phytoplankton to higher trophic levels. However, little is known of the chemical habitat occupied by Arctic invertebrate species, and of their responses to changes in seawater pH. Therefore, understanding krill’s responses to low pH conditions has important implications for the prediction of how Arctic marine communities may respond to future ocean change. Here, we present natural seawater carbonate chemistry conditions found in the late polar winter (April) in Kongsfjord, Svalbard (79°North) as well as the response of the Arctic krill, Thysanoessa inermis, exposed to a range of low pH conditions. Standard metabolic rate (measured as oxygen consumption) and energy metabolism markers (incl. adenosine triphosphate (ATP) and l-lactate) of T. inermis were examined. We show that after a 7 days experiment with T. inermis, no significant effects of low pH on MO2, ATP and l-lactate were observed. Additionally, we report carbonate chemistry from within Kongsfjord, which showed that the more stratified inner fjord had lower total alkalinity, higher dissolved inorganic carbon, pCO2 and lower pH than the well-mixed outer fjord. Consequently, our results suggest that overwintering individuals of T. inermis may possess sufficient ability to tolerate short-term low pH conditions due to their migratory behaviour, which exposes T. inermis to the naturally varying carbonate chemistry observed within Kongsfjord, potentially allowing T. inermis to tolerate future OA scenarios

    Multiorgan MRI findings after hospitalisation with COVID-19 in the UK (C-MORE): a prospective, multicentre, observational cohort study

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    Introduction: The multiorgan impact of moderate to severe coronavirus infections in the post-acute phase is still poorly understood. We aimed to evaluate the excess burden of multiorgan abnormalities after hospitalisation with COVID-19, evaluate their determinants, and explore associations with patient-related outcome measures. Methods: In a prospective, UK-wide, multicentre MRI follow-up study (C-MORE), adults (aged ≥18 years) discharged from hospital following COVID-19 who were included in Tier 2 of the Post-hospitalisation COVID-19 study (PHOSP-COVID) and contemporary controls with no evidence of previous COVID-19 (SARS-CoV-2 nucleocapsid antibody negative) underwent multiorgan MRI (lungs, heart, brain, liver, and kidneys) with quantitative and qualitative assessment of images and clinical adjudication when relevant. Individuals with end-stage renal failure or contraindications to MRI were excluded. Participants also underwent detailed recording of symptoms, and physiological and biochemical tests. The primary outcome was the excess burden of multiorgan abnormalities (two or more organs) relative to controls, with further adjustments for potential confounders. The C-MORE study is ongoing and is registered with ClinicalTrials.gov, NCT04510025. Findings: Of 2710 participants in Tier 2 of PHOSP-COVID, 531 were recruited across 13 UK-wide C-MORE sites. After exclusions, 259 C-MORE patients (mean age 57 years [SD 12]; 158 [61%] male and 101 [39%] female) who were discharged from hospital with PCR-confirmed or clinically diagnosed COVID-19 between March 1, 2020, and Nov 1, 2021, and 52 non-COVID-19 controls from the community (mean age 49 years [SD 14]; 30 [58%] male and 22 [42%] female) were included in the analysis. Patients were assessed at a median of 5·0 months (IQR 4·2–6·3) after hospital discharge. Compared with non-COVID-19 controls, patients were older, living with more obesity, and had more comorbidities. Multiorgan abnormalities on MRI were more frequent in patients than in controls (157 [61%] of 259 vs 14 [27%] of 52; p&lt;0·0001) and independently associated with COVID-19 status (odds ratio [OR] 2·9 [95% CI 1·5–5·8]; padjusted=0·0023) after adjusting for relevant confounders. Compared with controls, patients were more likely to have MRI evidence of lung abnormalities (p=0·0001; parenchymal abnormalities), brain abnormalities (p&lt;0·0001; more white matter hyperintensities and regional brain volume reduction), and kidney abnormalities (p=0·014; lower medullary T1 and loss of corticomedullary differentiation), whereas cardiac and liver MRI abnormalities were similar between patients and controls. Patients with multiorgan abnormalities were older (difference in mean age 7 years [95% CI 4–10]; mean age of 59·8 years [SD 11·7] with multiorgan abnormalities vs mean age of 52·8 years [11·9] without multiorgan abnormalities; p&lt;0·0001), more likely to have three or more comorbidities (OR 2·47 [1·32–4·82]; padjusted=0·0059), and more likely to have a more severe acute infection (acute CRP &gt;5mg/L, OR 3·55 [1·23–11·88]; padjusted=0·025) than those without multiorgan abnormalities. Presence of lung MRI abnormalities was associated with a two-fold higher risk of chest tightness, and multiorgan MRI abnormalities were associated with severe and very severe persistent physical and mental health impairment (PHOSP-COVID symptom clusters) after hospitalisation. Interpretation: After hospitalisation for COVID-19, people are at risk of multiorgan abnormalities in the medium term. Our findings emphasise the need for proactive multidisciplinary care pathways, with the potential for imaging to guide surveillance frequency and therapeutic stratification

    Carrying the beacon of excellence: social class differentiation and anxiety at a time of transition

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    In the current performance and "excellence" culture that has so bewitched politicians and beset educators, there are no discourses available to voice and to make sense of the anxieties that consistently arise for children who are pushed towards ever-higher performance. Drawing on the findings from a study of children"s transitions from primary to secondary school, this paper examines some of the structural and emotional consequences of current school-choice policy in the UK. Deep-seated fears of downward mobility held by some sections of the middle classes are potently mobilized when faced with the constraints of local secondary schools markets. Children from professional middle-class families are pushed towards high performance as a response to these fears with parents using a range of strategies to place their child in a high performing school, including entering them for selective schools" entrance examinations. In the pursuit of the kind of attainment seen to be necessary in order to ensure the successful reproduction of professional middle-class status, we argue that difficult emotions have to be suppressed or split off. For middle-class girls in particular, the constant striving for and achievement of high attainment, rather than unproblematically engendering a sense of confidence in their abilities, can produce a sense of never being good enough. Nor is it only the middle classes who are implicated in these processes. There are serious consequences for working-class children and we discuss how they are positioned in relation to UK policy initiatives that prioritize "excellence
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