546 research outputs found

    Regional Differences of Cell Sizes in the Human Stratum Corneum. Part I

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    Individual non-damaged horny cells can be removed from the human stratum corneum by a modification of the corneocyte count technique. Nine sites from four men were sampled and 50 cells from each specimen measured with a filar micrometer eyepiece. The longest and shortest diameters in micra and the surface area, calculated as an ellipse in square micra, were determined. Individual horny cells are much larger than previously described in the literature. Small cells, 34 μ to 36 μ in diameter were found on forehead and hand, larger cells, 41 μ to 44μ are typical for thigh axilla. Highly significant statistical differences for multiple sites of the human body were found when t-tests and the analysis of variance were applied. The regional differences in cell sizes are discussed

    Quantitative Microbiology of the Scalp in Non-Dandruff, Dandruff, and Seborrheic Dermatitis

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    The composition of the scalp microflora was assessed quantitatively in normal individuals and in patients with dandruff and seborrheic dermatitis, disorders characterized by increasing scalin. Three organisms were constantly found: (1) Pityrosporum, (2) aerobic cocci, and (3) Corynebacterium acnes. Pitrosporum (mainly Pityrosporum ovale) made up 46% of the total microflora in normals, 74% in dandruff, and 83% in seborrheic dermatitis. The geometric mean number of organisms per cm2 in non-dandruff subjects was 5.04 × 105; 9.22 × 105 in dandruff subjects; and 6.45 × 105 in those with seborrheic dermatitis. The cocci were dominantly Baird-Parkertype SII and no quantitative or qualitative change occurred in the scaling disorders. C. acnes comprised 26% of the flora on the normal scalp, 6% in dandruff, and only 1% in seborrheic dermatitis. These results differ significantly from previous reports which describe a much more complex microflora and suggest an etiologic role for microorganisms in dandruff

    Evolutionary Drivers of Protein Shape

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    Diffusional motion within the crowded environment of the cell is known to be crucial to cellular function as it drives the interactions of proteins. However, the relationships between protein diffusion, shape and interaction, and the evolutionary selection mechanisms that arise as a consequence, have not been investigated. Here, we study the dynamics of triaxial ellipsoids of equivalent steric volume to proteins at different aspect ratios and volume fractions using a combination of Brownian molecular dynamics and geometric packing. In general, proteins are found to have a shape, approximately Golden in aspect ratio, that give rise to the highest critical volume fraction resisting gelation, corresponding to the fastest long-time self-diffusion in the cell. The ellipsoidal shape also directs random collisions between proteins away from sites that would promote aggregation and loss of function to more rapidly evolving nonsticky regions on the surface, and further provides a greater tolerance to mutation

    Healthcare-associated outbreak of meticillin-resistant Staphylococcus aureus bacteraemia: role of a cryptic variant of an epidemic clone

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    BACKGROUND New strains of meticillin-resistant Staphylococcus aureus (MRSA) may be associated with changes in rates of disease or clinical presentation. Conventional typing techniques may not detect new clonal variants that underlie changes in epidemiology or clinical phenotype. AIM To investigate the role of clonal variants of MRSA in an outbreak of MRSA bacteraemia at a hospital in England. METHODS Bacteraemia isolates of the major UK lineages (EMRSA-15 and -16) from before and after the outbreak were analysed by whole-genome sequencing in the context of epidemiological and clinical data. For comparison, EMRSA-15 and -16 isolates from another hospital in England were sequenced. A clonal variant of EMRSA-16 was identified at the outbreak hospital and a molecular signature test designed to distinguish variant isolates among further EMRSA-16 strains. FINDINGS By whole-genome sequencing, EMRSA-16 isolates during the outbreak showed strikingly low genetic diversity (P < 1 × 10(-6), Monte Carlo test), compared with EMRSA-15 and EMRSA-16 isolates from before the outbreak or the comparator hospital, demonstrating the emergence of a clonal variant. The variant was indistinguishable from the ancestral strain by conventional typing. This clonal variant accounted for 64/72 (89%) of EMRSA-16 bacteraemia isolates at the outbreak hospital from 2006. CONCLUSIONS Evolutionary changes in epidemic MRSA strains not detected by conventional typing may be associated with changes in disease epidemiology. Rapid and affordable technologies for whole-genome sequencing are becoming available with the potential to identify and track the emergence of variants of highly clonal organisms

    Enforcement and compliance: critical practices for community rehabilitation companies and the new NPS?

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    Efforts to secure compliance have always been a core element of probation practice,although compliance has been constructed in diverse ways and promoted through different means throughout its history. This article takes a brief historical perspective and reviews recent research on enforcement practices and developing understandings of compliance. These guide a critical discussion of the practices that might develop as responsibilities for enforcement are divided between the new National Probation Service (NPS) and Community Rehabilitation Companies (CRCs) under the Transforming Rehabilitation agenda, highlighting inevitable tensions and challenges, and anticipating how inter-agency practices might shape the ongoing construction of compliance. Charging more than one agency with responsibilities in relation to enforcement is tricky and creates risks in terms of legitimacy, credibility and justice. On the whole, future prospects seem difficult, but not hopeless and, in particular, there are examples of positive practices in probation and youth justice for the NPS and CRCs to draw upon as they develop their inter-agency structures and processes. Elsewhere, initiatives in problem-solving courts, focused, for example, on drug users, may also give indicators of constructive ways forwar
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