641 research outputs found

    Glycan analysis of the chicken synaptic plasma membrane glycoproteins - a major synaptic N-glycan carries the LewisX determinant

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    The majority of plasma membrane components are glycosylated. It is now widely accepted that this post-translational modification is crucial during the establishment, maintenance and function of the nervous system. Despite its significance, structural information about the glycosylation of nervous system specific glycoproteins is very limited. In the present study the major glycan structure of the chicken synaptic plasma membrane (SPM) associated glycoprotein glycans were determined. N-glycans were released by hydozinnolysis, labelled with 2-aminobenzam,ide, treated with neuraminidase and subsequently fractionated by size exclusion chromatography. Individual fractions were characterized by combination of high-pressure liquid chromatography, exoglicosidase treatment or reagent array analysis method (RAAM). In addition to oligomannose-type glycans, core-fucosylated complex glycans with biantennary bisecting glycans carrying the LewisX epitope were most abundant. The overall chicken glycan profile was strikingly similar to the rat brain glycan profile. The presence of the LewisX determinant in relatively large proportions suggests a tissue-specific function for these glycans

    Treatment of Clostridium difficile infection: a national survey of clinician recommendations and the use of faecal microbiota transplantation

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    Adherence to Clostridium difficile infection treatment guidelines is associated with lower recurrence rates and mortality as well as cost savings. Our survey of Irish clinicians indicates that patients are managed using a variety of approaches. FMT is potentially underutilised despite its recommendation in national and European guidelines

    Past and possible future evolution of the Yukon Flats southern upland yedoma region, Alaska

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    The course of permafrost degradation depends on climate, vegetation, disturbance, and excess groundice content and distribution, which vary over time. The first three of these drivers are undergoing considerable change with arctic warming. Using combined lake-sediment records, field observations, aerial observations and LiDAR imagery, we reconstructed the late-Quaternary history of the marginal upland of the Yukon Flats, interior Alaska, a loess-mantled region with massive ground ice and numerous thermokarst lakes that is identified as yedoma. A switch to warmer, moister conditions during deglaciation triggered substantial thermal erosion and transport of silt, which washed into existing basins and formed widespread linear corrugations cutting across the uplands. Lakes began to form via thermokarst as early as 13,000 cal yr BP. Lakes intersect the corrugations, indicating lake formation followed initial landscape instability. Charcoal in basal sediments indicates fire may have influenced lake initiation. Small-scale surface topography revealed by LiDAR images includes deep gullies, features resembling lake drainage channels, and lowered lake shorelines. After ca 10,000 yr BP the region became colonized by dense evergreen conifer forest, which likely served to stabilize and insulate the ground surface, preventing the continuation of the high rates of permafrost degradation recorded in the earliest Holocene. Initial lake lowering and generation of steep local topography favouring drying of uplands, plus a summer water deficit, have also likely combined to shift the system to a more quiescent state through much of the Holocene. However, these changes have not prevented lake drainage events entirely. In 2013, several lakes drained or partially drained, possibly in response to fires and a high spring melt-water volume. The observed pattern of drainage is echoed in the older features preserved on the land surface. Based on the Holocene evolution of the region, increasing regional moisture and/or fire disturbance in the future could lead to an increase in permafrost degradation and lake drainage events

    Maintenance of genetic variation in plants and pathogens involves complex networks of gene-for-gene interactions

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    The RPP13 [recognition of Hyaloperonospora arabidopsidis (previously known as Peronospora parasitica)] resistance (R) gene in Arabidopsis thaliana exhibits the highest reported level of sequence diversity among known R genes. Consistent with a co-evolutionary model, the matching effector protein ATR13 (A. thaliana-recognized) from H. arabidopsidis reveals extreme levels of allelic diversity. We isolated 23 new RPP13 sequences from a UK metapopulation, giving a total of 47 when combined with previous studies. We used these in functional studies of the A. thaliana accessions for their resistance response to 16 isolates of H. arabidopsidis. We characterized the molecular basis of recognition by the expression of the corresponding ATR13 genes from these 16 isolates in these host accessions. This allowed the determination of which alleles of RPP13 were responsible for pathogen recognition and whether recognition was dependent on the RPP13/ATR13 combination. Linking our functional studies with phylogenetic analysis, we determined that: (i) the recognition of ATR13 is mediated by alleles in just a single RPP13 clade; (ii) RPP13 alleles in other clades have evolved the ability to detect other pathogen ATR protein(s); and (iii) at least one gene, unlinked to RPP13 in A. thaliana, detects a different subgroup of ATR13 allele

    ‘Manic mums’ and ‘distant dads’? Gendered geographies of care and the journey to school

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    This is the post-print version of the final paper published in Health & Place. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2011 Elsevier B.V.Research in the geographies of care has identified the central role of mothers in caring for children, although much less explored are the experiences of men who also participate in care. Drawing upon research conducted in the UK with children and their families, this paper contributes to existing debates in the geographies of care by exploring a relatively new space of caring, namely the escort of primary school children to and from school and other settings. The paper explores mothers’ and fathers’ involvement in escorting children, the extent and nature of participation and also how distinct gendered forms of caring practices are established. In doing so, the paper also considers the importance of place and local cultures of parenting which inform these gendered carescapes
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