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Robinson, C.

Publications and source records attributed to Robinson, C..

5 recordsLinked to original sources

Monitoring the eradication of the highly invasive topmouth gudgeon (Pseudorasbora parva) using a novel eDNA assay

Aquatic Invasive Species (AIS) represent an important threat for Biodiversity and are one of the factors determining the ecological integrity of water bodies under the Water Framework Directive. Eradication is one of the most effective tools for the management of invasive species but has important economic and ecological trade-offs and its success needs to be carefully monitored. We assessed the eradication success of the topmouth gudgeon (Pseudorasbora parva), an invasive fish that poses significant risks to endemic aquatic fauna, in four ponds previously treated with the piscicide Rotenone using a novel environmental DNA (eDNA)-qPCR assay. Topmouth gudgeon was detected in all four treated ponds using 750 mL water samples and in three of the ponds using 15 mL samples, despite the eradication treatment. The highly sensitive qPCR assay detected topmouth gudgeon in a significantly greater proportion of sites (77.5%) than eDNA detection methods based on conventional PCR (35%). Our results highlight the difficulties of eradicating invasive fish and the need to incorporate reliable monitoring methods as part of a risk management strategy under the Water Framework Directive.

ecology

Optimisation of a novel method for the production of single-span membrane proteins in Escherichia coli

The large-scale production and isolation of recombinant protein is a central element of the biotechnology industry and many of the products have proved extremely beneficial for therapeutic medicine. Escherichia coli is the microorganism of choice for the expression of heterologous proteins for therapeutic application, and a range of high-value proteins have been targeted to the periplasm using the well characterised Sec protein export pathway. More recently, the ability of the second mainstream protein export system, the twin-arginine translocase, to transport fully-folded proteins into the periplasm of not only E. coli, but other Gram-negative bacteria, has captured the interest of the biotechnology industry.\n\nIn this study, we have used a novel approach to block the export of a heterologous Tat substrate in the later stages of the export process, and thereby generate a single-span membrane protein with the soluble domain positioned on the periplasmic side of the inner membrane. Biochemical and immuno-electron microscopy approaches were used to investigate the export of human growth hormone by the twin-arginine translocase, and the generation of a single span membrane-embedded variant. This is the first time that a bona-fide biotechnologically-relevant protein has been exported by this machinery and visualised directly in this manner. The data presented here demonstrate a novel method for the production of single-span membrane proteins in E. coli.\n\nHighlightsO_LIThe Tat translocase has captured the interest of the biotechnology industry\nC_LIO_LIBiochemical and immuno-EM approaches showed efficient export of hGH by Tat\nC_LIO_LIA novel approach was used to block export of hGH by Tat in E. coli\nC_LIO_LIWe demonstrate a novel method for producing single-span membrane proteins in E. coli\nC_LI

biochemistry

Simultaneous detection of invasive signal crayfish, endangered white-clawed crayfish and the crayfish plague pathogen using environmental DNA

Aquatic Invasive Species (AIS) are important vectors for the introduction of novel pathogens which can, in turn, become drivers of rapid ecological and evolutionary change, compromising the persistence of native species. Conservation strategies rely on accurate information regarding presence and distribution of AIS and their associated pathogens to prevent or mitigate negative impacts, such as predation, displacement or competition with native species for food, space or breeding sites. Environmental DNA is increasingly used as a conservation tool for early detection and monitoring of AIS. We used a novel eDNA high-resolution melt curve (HRM) approach to simultaneously detect the UK endangered native crayfish (Austropotamobius pallipes), the highly invasive signal crayfish (Pacifastacus leniusculus) and their dominant pathogen, Aphanomyces astaci, (causative agent of crayfish plague). We validated the approach with laboratory and field samples in areas with known presence or absence of both crayfish species as well as the pathogen, prior to the monitoring of areas where their presence was unknown. We identified the presence of infected signal crayfish further upstream than previously detected in an area where previous intensive eradication attempts had taken place, and the coexistence of both species in plague free catchments. We also detected the endangered native crayfish in an area where trapping had failed. With this method, we could estimate the distribution of native and invasive crayfish and their infection status in a rapid, cost effective and highly sensitive way, providing essential information for the development of conservation strategies in catchments with populations of endangered native crayfish.

ecology

Predictors of emergency department attendance following NHS 111 calls for children and young people: analysis of linked data

ObjectivesTo assess whether clinical input during calls to the NHS 111 telephone-based advice service is associated with lower rates of subsequent emergency department attendance and hospital admission.\n\nDesignAlthough NHS 111 largely employs non-clinical call handling staff to triage calls using computerised clinical decision support software, some support is available from clinical supervisors, and additionally some calls are referred to out-of-hours General Practitioners (GP). We used linked data sets to examine GP and secondary care activity following calls to NHS 111, adjusting for the patient characteristics, signs and symptoms recorded during the NHS 111 call.\n\nSettingOut-of-hours care in three areas of North West London that have an integrated approach to delivering NHS 111 and out-of-hours GP care.\n\nParticipantsNHS 111 calls for children and young people aged 15 years or under. We excluded calls that were diverted to the emergency ( 999) service or where patients were advised to go to an emergency department. This left callers who were either referred to a GP or advised to manage their health needs at home.\n\nPrimary and secondary outcome measuresThe percentage of callers attending any emergency departments, major emergency department, or minor injury unit within ten hours of the NHS 111 call, and the percentage admitted to hospital following visits to emergency departments.\n\nResultsOf the 10,356 callers, 2,898 (28.0%) were advised by NHS 111 to manage their health needs at home, with an appointment with an out-of-hours GP made for the remaining 7,458 (72.0%). 14.9% (432/2,898) of the callers who were advised by NHS 111 to manage their health needs at home attended an emergency department with ten hours, compared with 16% (1,207/7,458) of callers who had an out-of-hours appointment with an out-of-hours GP. After adjusting for patient characteristics, GP out-of-hours appointment was associated with lower rates of emergency department attendance (adjusted odds ratio, 0.86, 95% CI, 0.75-0.99),). When we subset emergency department types, a GP out-of-hours appointment was associated with lower rates of minor injury unit attendance (adjusted odds ratio, 0.32, 95% CI, 0.23 - 0.44) but not major emergency department attendance (adjusted odds ratio 1.06, 95% CI 0.90-1.24). There was no association with hospital admission. Review by an NHS 111 clinical supervisor was associated with fewer emergency department attendances (adjusted OR 0.77, 95% CI, 0.62-0.97).\n\nConclusionsClinical input during or following out-of-hours calls to NHS 111 was associated with lower rates of emergency department utilisation for children and young people, though the reduction may be concentrated in lower intensity care settings. Thus, there may be potential to reduce the use of emergency care by providing access to clinical advice or out-of-hour services in other settings through the NHS 111 telephone service.

epidemiology

Structure and function of the intermembrane space domain of mammalian FoF1 ATP synthase

Mitochondrial FoF1 ATP synthase is a membrane bound molecular machine central to cellular energy conversion and cristae architecture. Recently, a novel domain has been visualized in the intermembrane space region of mammalian ATP synthase. The complete three-dimensional (3D) structure, composition and function of this domain - which we term intermembrane space domain (IMD) - are unknown. Here, we present two distinct 3D structures of monomeric bovine FoF1 ATP synthase by single particle cryo-electron microscopy (cryo-EM) that differ by the presence and absence of the IMD. Comparison of both structures reveals the IMD to be a bipartite and weakly associated domain of FoF1 ATP synthase. The tubular sub-domain of the IMD appears to contact the rotor-ring region, its globular sub-domain is anchored in the membrane-bending kink of the ATP synthase. However, absence of the IMD does not impact the kink in the transmembrane region ruling out a functional role in membrane bending. By combining our structural analysis with chemical cross-linking and reported biochemical, genetic and structural data we identify 6.8PL and DAPIT as the subunits forming the intermembrane space domain. We compare the present structure of the mammalian IMD in the bovine FoF1 ATP synthase monomer with structures of dimeric FoF1 ATP synthase from yeast and ciliate showing that the IMD is a common, but structurally divergent feature of several mitochondrial ATP synthases. On the basis of our analysis we discuss potential functions of the novel domain in rotary catalysis, oligomerization and mitochondrial permeability transition.

biophysics