36 research outputs found
Foot and Mouth Epidemic Reduces Cases of Human Cryptosporidiosis in Scotland.
In Scotland, rates of cryptosporidiosis infection in humans peak during the spring, a peak that is coincident with the peak in rates of infection in farm animals (during lambing and calving time). Here we show that, during the outbreak of foot and mouth disease (FMD) in 2001, there was a significant reduction in human cases of cryptosporidiosis infection in southern Scotland, where FMD was present, whereas, in the rest of Scotland, there was a reduction in cases that was not significant. We associate the reduction in human cases of cryptosporidiosis infection with the reduction in the number of young farm animals, together with restrictions on movement of both farm animals and humans, during the outbreak of FMD in 2001. We further show that, during 2002, there was recovery in the rate of cryptosporidiosis infection in humans throughout Scotland, particularly in the FMD-infected area, but that rates of infection remained lower, though not significantly, than pre-2001 levels
Multiplex T-RFLP allows for increased target number and specificity : detection of Salmonella enterica and six species of Listeria in a single test
A multiplex T-RFLP test was developed to detect and identify Salmonella enterica and all six species of Listeria inoculated into milk at minimal levels. Extensive in silico analysis was used to design a fifteen-primer, six-amplimer methodology and in vitro application showed target organism DNA, when amplified individually, yielded the predicted terminal restriction fragments (TRFs) following digestion. Non-target organisms were either not-amplified or yielded TRFs which did not interfere with target identification. Multiple target DNA analysis gave over 86% detection of total TRFs predicted, and this was improved to over 90% detection of total TRFs predicted when only two target DNA extracts were combined analysed. Co-inoculation of milk with five strains each of the target species of S. enterica and L. monocytogenes, along with five strains of the non-target species E. coli was followed by enrichment in SEL medium for M-TRFLP analysis. This allowed for detection of both target species in all samples, with detection of one S. enterica and two Listeria TRFs in all cases, and detection of a second S. enterica TRF in 91% of cases. This was from an initial inoculum of <5 cfu per 25 ml milk with a background of competing E. coli present, and gave a result from sampling of under 20 hours. The ability to increase target species number without loss of sensitivity means that extensive screening can be performed at reduced cost due to a reduction in the number of tests required
Evolution of an Agriculture-Associated Disease Causing Campylobacter coli Clade: Evidence from National Surveillance Data in Scotland
The common zoonotic pathogen Campylobacter coli is an important cause of bacterial gastroenteritis worldwide but its evolution is incompletely understood. Using multilocus sequence type (MLST) data of 7 housekeeping genes from a national survey of Campylobacter in Scotland (2005/6), and a combined population genetic-phylogenetics approach, we investigated the evolutionary history of C. coli. Genealogical reconstruction of isolates from clinical infection, farm animals and the environment, revealed a three-clade genetic structure. The majority of farm animal, and all disease causing genotypes belonged to a single clade (clade 1) which had comparatively low synonymous sequence diversity, little deep branching genetic structure, and a higher number of shared alleles providing evidence of recent clonal decent. Calibration of the rate of molecular evolution, based on within-species genetic variation, estimated a more rapid rate of evolution than in traditional estimates. This placed the divergence of the clades at less than 2500 years ago, consistent with the introduction of an agricultural niche having had an effect upon the evolution of the C. coli clades. Attribution of clinical isolate genotypes to source, using an asymmetric island model, confirmed that strains from chicken and ruminants, and not pigs or turkeys, are the principal source of human C. coli infection. Taken together these analyses are consistent with an evolutionary scenario describing the emergence of agriculture-associated C. coli lineage that is an important human pathogen
Does age acquired immunity confer selective protection to common serotypes of Campylobacter jejuni?
BACKGROUND: Campylobacter infection is a major cause of bacterial gastrointestinal disease. Exposure to Campylobacter is known to produce an immune response in humans that can prevent future symptomatic infections. Further, studies of the general population have shown that seroprevalence to Campylobacter increases with age. METHODS: A large collection of serotyped Campylobacter isolates, obtained from human clinical faecal samples, were analysed by comparing the ratio of uncommon to common serotypes by different age groups, using χ(2 )tests. RESULTS: We have identified that older age groups, as well as having generally lower incidence, are significantly less likely to be infected by the more common serotypes. CONCLUSION: These results are indicative of acquired immunity, however, further studies are needed to rule out the confounding effects of the variations in exposure pathways experienced by different age groups
Institutional creativity and pathologies of potential space: The modern university
This paper proposes the applicability of object relations psychoanalytic conceptions of dialogue (Ogden, 1986, 1993) to thinking about relationships and relational structures and their governance in universities. It proposes that: the qualities of dialogic relations in creative institutions are the proper index of creative productivity; that is of, as examples, ’thinking’ (Evans, 2004), ’emotional learning’ (Salzberger-Wittenburg et al., 1983) or ’criticality’ (Barnett, 1997); contemporary institutions’ explicit preoccupation in assuring, monitoring and managing creative ’dialogue’ can, in practice, pervert creative processes and thoughtful symbolic productivity, thus inhibiting students’ development and the quality of ’thinking space’ for teaching and research. In this context the paper examines uncanny and perverse connections between Paulo Freire’s (1972) account of educational empowerment and dialogics (from his Pedagogy of the oppressed) to the consumerist (see, for example, Clarke & Vidler, 2005) rhetoric of student empowerment, as mediated by some strands of managerialism in contemporary higher education. The paper grounds its critique of current models of dialogue, feedback loops, audit and other mechanisms of accountability (Power, 1997; Strathern, 2000), in a close analysis of how creative thinking emerges. The paper discusses the failure to maintain a dialogic space in humanities and social science areas in particular, exploring psychoanalytic conceptions from Donald Winnicott (1971), Milner (1979), Thomas Ogden (1986) and Csikszentmihalyi (1997). Coleridge’s ideas about imagination as the movement of thought between subjective and objective modes are discussed in terms of both intra- and inter-subjective relational modes of ’dialogue’, which are seen as subject to pathology in the pathologically structured psychosocial environment. Current patterns of institutional governance, by micromanaging dialogic spaces, curtail the ’natural’ rhythms and temporalities of imagination by giving an over-emphasis to the moment of outcome, at the expense of holding the necessary vagaries of process in the institutional ’mind’. On the contrary, as this paper argues, creative thinking lies in sporadic emergences at the conjunction of object/(ive) outcome and through (thought) processes
A DNA Barcode Library for North American Ephemeroptera: Progress and Prospects
DNA barcoding of aquatic macroinvertebrates holds much promise as a tool for taxonomic research and for providing the reliable identifications needed for water quality assessment programs. A prerequisite for identification using barcodes is a reliable reference library. We gathered 4165 sequences from the barcode region of the mitochondrial cytochrome c oxidase subunit I gene representing 264 nominal and 90 provisional species of mayflies (Insecta: Ephemeroptera) from Canada, Mexico, and the United States. No species shared barcode sequences and all can be identified with barcodes with the possible exception of some Caenis. Minimum interspecific distances ranged from 0.3–24.7% (mean: 12.5%), while the average intraspecific divergence was 1.97%. The latter value was inflated by the presence of very high divergences in some taxa. In fact, nearly 20% of the species included two or three haplotype clusters showing greater than 5.0% sequence divergence and some values are as high as 26.7%. Many of the species with high divergences are polyphyletic and likely represent species complexes. Indeed, many of these polyphyletic species have numerous synonyms and individuals in some barcode clusters show morphological attributes characteristic of the synonymized species. In light of our findings, it is imperative that type or topotype specimens be sequenced to correctly associate barcode clusters with morphological species concepts and to determine the status of currently synonymized species
Procalcitonin evaluation of antibiotic use in COVID-19 hospitalised patients (PEACH): protocol for a retrospective observational study
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel virus responsible for the coronavirus disease 2019 (COVID-19) pandemic. Although COVID-19 is a viral illness, many patients admitted to hospital are prescribed antibiotics, based on concerns that COVID-19 patients may experience secondary bacterial infections, and the assumption that they may respond well to antibiotic therapy. This has led to an increase in antibiotic use for some hospitalised patients at a time when accumulating antibiotic resistance is a major global threat to health. Procalcitonin (PCT) is an inflammatory marker measured in blood samples and widely recommended to help diagnose bacterial infections and guide antibiotic treatment. The PEACH study will compare patient outcomes from English and Welsh hospitals that used PCT testing during the first wave of the COVID-19 pandemic with those from hospitals not using PCT. It will help to determine whether, and how, PCT testing should be used in the NHS in future waves of COVID-19 to protect patients from antibiotic overuse. PEACH is a retrospective observational cohort study using patient-level clinical data from acute hospital Trusts and Health Boards in England and Wales. The primary objective is to measure the difference in antibiotic use between COVID-19 patients who did or did not have PCT testing at the time of diagnosis. Secondary objectives include measuring differences in length of stay, mortality, intensive care unit admission, and resistant bacterial infections between these groups
Climate, human behaviour or environment: individual-based modelling of Campylobacter seasonality and strategies to reduce disease burden
Acknowledgements: We thank colleagues within the Modelling, Evidence and Policy Research Group for useful feedback on this manuscript. Competing interests: The authors declare that they have no competing interests. Availability of data and materials: The R code used in this research is available at https://gitlab.com/rasanderson/campylobacter-microsimulation; it is platform independent, R version 3.3.0 and above. Funding: This research was funded by Medical Research Council Grant, Natural Environment Research Council, Economic and Social Research Council, Biotechnology and Biological Sciences Research Council, and the Food Standards Agency through the Environmental and Social Ecology of Human Infectious Diseases Initiative (Sources, seasonality, transmission and control: Campylobacter and human behaviour in a changing environment (ENIGMA); Grant Reference G1100799-1). PRH, SJO’B, and IRL are funded in part by the NIHR Health Protection Research Unit in Gastrointestinal Infection, at the University of Liverpool. PRH and IRL are also funded in part by the NIHR Health Protection Research Unit in Emergency Preparedness and Response, at King’s College London. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR, the Department of Health or Public Health England.Peer reviewedPublisher PD
Vision, challenges and opportunities for a Plant Cell Atlas
With growing populations and pressing environmental problems, future economies will be increasingly plant-based. Now is the time to reimagine plant science as a critical component of fundamental science, agriculture, environmental stewardship, energy, technology and healthcare. This effort requires a conceptual and technological framework to identify and map all cell types, and to comprehensively annotate the localization and organization of molecules at cellular and tissue levels. This framework, called the Plant Cell Atlas (PCA), will be critical for understanding and engineering plant development, physiology and environmental responses. A workshop was convened to discuss the purpose and utility of such an initiative, resulting in a roadmap that acknowledges the current knowledge gaps and technical challenges, and underscores how the PCA initiative can help to overcome them.</jats:p