351 research outputs found

    The orphan germinant receptor protein GerXAO (but not GerX3b) is essential for L-alanine induced germination in Clostridium botulinum Group II

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    Clostridium botulinum is an anaerobic spore forming bacterium that produces the potent botulinum neurotoxin that causes a severe and fatal neuro-paralytic disease of humans and animals (botulism). C. botulinum Group II is a psychrotrophic saccharolytic bacterium that forms spores of moderate heat resistance and is a particular hazard in minimally heated chilled foods. Spore germination is a fundamental process that allows the spore to transition to a vegetative cell and typically involves a germinant receptor (GR) that responds to environmental signals. Analysis of C. botulinum Group II genomes shows they contain a single GR cluster (gerX3b), and an additional single gerA subunit (gerXAO). Spores of C. botulinum Group II strain Eklund 17B germinated in response to the addition of L-alanine, but did not germinate following the addition of exogenous Ca2+-DPA. Insertional inactivation experiments in this strain unexpectedly revealed that the orphan GR GerXAO is essential for L-alanine stimulated germination. GerX3bA and GerX3bC affected the germination rate but were unable to induce germination in the absence of GerXAO. No role could be identified for GerX3bB. This is the first study to identify the functional germination receptor of C. botulinum Group II

    Postgraduate education for Chinese medicine practitioners: a Hong Kong perspective

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    <b>Background</b> Despite Hong Kong government's official commitment to the development of traditional Chinese medicine (TCM) over the last ten years, there appears to have been limited progress in public sector initiated career development and postgraduate training (PGT) for public university trained TCM practitioners. Instead, the private TCM sector is expected to play a major role in nurturing the next generation of TCM practitioners. In the present study we evaluated TCM graduates' perspectives on their career prospects and their views regarding PGT.<p></p> <b>Method</b> Three focus group discussions with 19 local TCM graduates who had worked full time in a clinical setting for fewer than 5 years. <p></p> <b>Results</b> Graduates were generally uncertain about how to develop their career pathways in Hong Kong with few postgraduate development opportunities; because of this some were planning to leave the profession altogether. Despite their expressed needs, they were dissatisfied with the current quality of local PGT and suggested various ways for improvement including supervised practice-based learning, competency-based training, and accreditation of training with trainee involvement in design and evaluation. In addition they identified educational needs beyond TCM, in particular a better understanding of western medicine and team working so that primary care provision might be more integrated in the future. <p></p> <b>Conclusion</b> TCM graduates in Hong Kong feel let down by the lack of public PGT opportunities which is hindering career development. To develop a new generation of TCM practitioners with the capacity to provide quality and comprehensive care, a stronger role for the government, including sufficient public funding, in promoting TCM graduates' careers and training development is suggested. Recent British and Australian experiences in prevocational western medicine training reform may serve as a source of references when relevant program for TCM graduates is planned in the futur

    Why do patients want to have their blood tested? A qualitative study of patient expectations in general practice

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    BACKGROUND: General practitioners often take their impression of patients' expectations into account in their decision to have blood tests done. It is commonly recommended to involve patients in decision-making during consultations. The study aimed to obtain detailed information on patients' expectations about blood tests. METHODS: Qualitative study among patients in waiting rooms of general practices. Each patient was presented with a short questionnaire about their preferences in terms of diagnostics. Patients who would like blood tests to be done were interviewed. RESULTS: Fifty-seven (26%) of the 224 respondents wanted blood tests. Twenty-two were interviewed. Patients overestimated the qualities of blood tests. Favourable test results were regarded as proof of good health. Patients regarded blood tests as a useful instrument to screen for serious disorders, and were confirmed in this belief by people in their social environment and by the media. Many patients expected their GP to take an active test ordering approach, though some indicated that they might be convinced if their GP proposed a wait-and-see policy. CONCLUSIONS: GPs' perceptions about patient expectations seem justified: patients appear to have high hopes for testing as a diagnostic tool. They expect diagnostic certainty without mistakes and a proof of good health. The question is whether it would be desirable to remove patients' misconceptions, allowing them to participate in policy decisions on the basis of sound information, or whether it would be better to leave the misconceptions uncontested, in order to retain the 'magic' of additional tests and reassure patients. We expect that clarifying the precise nature of patients' expectations by the GP may be helpful in creating a diagnostic strategy that satisfies both patients and GPs. GPs will have to balance the benefits of reassuring their patients by means of blood tests which may be unnecessary against the benefits of avoiding unnecessary tests. Further research is needed into the effects of different types of patient information and the effects of testing on satisfaction and anxiety

    Climate Change and Trophic Response of the Antarctic Bottom Fauna

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    BACKGROUND: As Earth warms, temperate and subpolar marine species will increasingly shift their geographic ranges poleward. The endemic shelf fauna of Antarctica is especially vulnerable to climate-mediated biological invasions because cold temperatures currently exclude the durophagous (shell-breaking) predators that structure shallow-benthic communities elsewhere. METHODOLOGY/PRINCIPAL FINDINGS: We used the Eocene fossil record from Seymour Island, Antarctic Peninsula, to project specifically how global warming will reorganize the nearshore benthos of Antarctica. A long-term cooling trend, which began with a sharp temperature drop approximately 41 Ma (million years ago), eliminated durophagous predators-teleosts (modern bony fish), decapod crustaceans (crabs and lobsters) and almost all neoselachian elasmobranchs (modern sharks and rays)-from Antarctic nearshore waters after the Eocene. Even prior to those extinctions, durophagous predators became less active as coastal sea temperatures declined from 41 Ma to the end of the Eocene, approximately 33.5 Ma. In response, dense populations of suspension-feeding ophiuroids and crinoids abruptly appeared. Dense aggregations of brachiopods transcended the cooling event with no apparent change in predation pressure, nor were there changes in the frequency of shell-drilling predation on venerid bivalves. CONCLUSIONS/SIGNIFICANCE: Rapid warming in the Southern Ocean is now removing the physiological barriers to shell-breaking predators, and crabs are returning to the Antarctic Peninsula. Over the coming decades to centuries, we predict a rapid reversal of the Eocene trends. Increasing predation will reduce or eliminate extant dense populations of suspension-feeding echinoderms from nearshore habitats along the Peninsula while brachiopods will continue to form large populations, and the intensity of shell-drilling predation on infaunal bivalves will not change appreciably. In time the ecological effects of global warming could spread to other portions of the Antarctic coast. The differential responses of faunal components will reduce the endemic character of Antarctic subtidal communities, homogenizing them with nearshore communities at lower latitudes

    Metabolism of halophilic archaea

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    In spite of their common hypersaline environment, halophilic archaea are surprisingly different in their nutritional demands and metabolic pathways. The metabolic diversity of halophilic archaea was investigated at the genomic level through systematic metabolic reconstruction and comparative analysis of four completely sequenced species: Halobacterium salinarum, Haloarcula marismortui, Haloquadratum walsbyi, and the haloalkaliphile Natronomonas pharaonis. The comparative study reveals different sets of enzyme genes amongst halophilic archaea, e.g. in glycerol degradation, pentose metabolism, and folate synthesis. The carefully assessed metabolic data represent a reliable resource for future system biology approaches as it also links to current experimental data on (halo)archaea from the literature

    Schools, families, and social reproduction

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    Neoliberal educational discourse across the Global North is marked by an increasing homogeneity, but this masks significant socio-spatial differences in the enactment of policy. The authors focus on four facets of roll-out neoliberalism in English education policy that have expanded the function of primary schools, and redrawn the boundary between state and family responsibilities. Specifically, these are increased state support for: (1) working parenthood through provision of wraparound childcare; (2) parent-child relationships through school-led provision of parenting classes; (3) parental involvement in children’s learning; and (4) child development through schools’ fostering of extracurricular activities. The politics of policies that both enhance state responsibility for, and influence in, matters that were previously within the purview of families are complex. The collective impact of these developments has been both to reform how the work of daily and generational social reproduction is done, and to reshape the social reproduction of a classed and gendered society

    Temporal controls on silicic acid utilisation along the West Antarctic Peninsula

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    The impact of climatic change along the Antarctica Peninsula has been widely debated in light of atmospheric/oceanic warming and increases in glacial melt over the past half century. Particular concern exists over the impact of these changes on marine ecosystems, not only on primary producers but also on higher trophic levels. Here we present a record detailing the historical controls on the biogeochemical cycling of silicic acid [Si(OH)4] on the west Antarctica Peninsula margin, a region in which the modern phytoplankton environment is constrained by seasonal sea-ice. We demonstrate that Si(OH)4 cycling through the Holocene alternates between being primarily regulated by sea-ice or glacial discharge from the surrounding grounded ice-sheet. With further climate-driven change and melting forecast for the 21st Century, our findings document the potential for biogeochemical cycling and multi-trophic interactions along the peninsula to be increasingly regulated by glacial discharge, altering food-web interactions
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