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Since their inception in the mid 1970s, the role of the diabetes nurse specialist (DNS) has become well established. However, their functions have not been clearly defined. This has resulted in the inclusion of a variety of activities in their job descriptions. While some of these are controversial, there is little dispute that a key component of the post is the evaluation, integration and (in some circumstances) the generation of research evidence. The purpose of this study was to explore the participation, attitudes, sources of support, and encouraging and discouraging factors experienced by DNSs in utilising research evidence. An associated study allowed comparison with a sample of non‐nurse specialists. Two hundred and ninety‐nine DNSs (response rate 72%) across seven of the eight regions of the National Health Service in England completed the questionnaire, and 133 nurses responded (response rate of 71 %) in the eighth region. The results suggest that DNSs are positive about utilising research evidence and more likely to be involved in research activities than non nurse specialists. However, unless issues around time and clinical workload are addressed, the potential of the DNS's role in promoting evidence‐based practice is unlikely to be fully realised.

Autoantibodies in the sera of patients with pernicious anemia recognize, in addition to the alpha subunit of the gastric H+/(+)-ATPase, an abundant gastric microsomal glycoprotein of apparent Mr 60,000-90,000. Herein we have colocalized the glycoprotein and the alpha subunit of the gastric H+/K(+)-ATPase to the tubulovesicular membranes of the parietal cell by immunogold electron microscopy. Moreover, the glycoprotein and the alpha subunit were coimmunoprecipitated, and copurified by immunoaffinity chromatography, with an anti-glycoprotein monoclonal antibody. The pig glycoprotein was purified by chromatography on tomato lectin-Sepharose, and five tryptic peptides from the purified glycoprotein were partially sequenced. The complete amino acid sequence, deduced from the nucleotide sequence of overlapping cDNA clones, showed 33% similarity to the sequence of the beta subunit of the pig kidney Na+/K(+)-ATPase. We therefore propose that the 60- to 90-kDa glycoprotein autoantigen is the beta subunit of the gastric H+/K(+)-ATPase and that the alpha and beta subunits of the proton pump are major targets for autoimmunization in autoimmune gastritis.

The parietal cell of the gastric mucosa undergoes rapid morphological transformation when it is stimulated to produce hydrochloric acid. In chemically fixed cells, this process is seen as a reduction in number of cytoplasmic 'tubulovesicles' as the apical surface of the cell progressively invaginates to increase the secretory surface area. It is widely believed that the tubulovesicles represent stored secretory membrane in the cytoplasm of the unstimulated cell, which is incorporated into the apical membrane upon stimulation, because they share H+,K+-ATPase activity with the apical membrane. However, fusion of tubulovesicles with the apical membrane concomitant with parietal cell activation has never been convincingly demonstrated. We have used fast freeze-fixation and freeze-substitution to study stages of morphological transformation in these cells. Tubulovesicles were not seen in the cytoplasm of any of our cryoprepared cells. Instead, the cytoplasm of the unstimulated cell contained numerous and densely packed helical coils of tubule, each having an axial core of cytoplasm. The helical coils were linked together by connecting tubules, lengths of relatively straight tubule. Lengths of straight connecting tubule also extended from coils lying adjacent to the apical and canalicular surfaces and ended at the apical and canaliculus membranes. Immunogold labelling with alpha- and beta-subunit-specific antibodies showed that the gastric H+,K+-ATPase was localized to the membranes of this tubular system, which therefore represented the configuration of the secretory membrane in the cytoplasm of the unstimulated parietal cell. Stimulation of the cells with histamine and isobutylmethylxanthine lead to modification of the tubular membrane system, correlated with progressive invagination of the apical membrane. The volume of the tubule lumen increased and, as this occurred, the tight spiral twist of the helical coils was lost, indicating that tubule distension was accounted for by partial unwinding. This exposed the cores of cytoplasm in the axes of the coils as rod-shaped elements of a three-dimensional reticulum, resembling a series of microvilli in random thin sections. Conversely, treatment with the H2 antagonist cimetidine caused severe contraction of the tubular membrane system and intracellular canaliculi. Our results indicate that tubulovesicles are an artifact of chemical fixation; consequently, they cannot have a role in parietal cell transformation. From our findings we propose an alternative model for morphological transformation in the parietal cell. This model predicts cytoskeleton-mediated control over expansion and contraction of the tubular membrane network revealed by cryopreparation. The model is compatible with the localization of cytoskeletal components in these cells.

The complexity of managing research knowledge into practice in health care is often underestimated. The wider policy demands for evidence based practice have been translated into strategies that encourage clinicians to explore the effectiveness of their clinical practice. These demands present a number of significant challenges in terms of the nature of evidence, its quality and completeness. However, occupational therapists and physiotherapists will have difficulty in meeting these demands without a supporting organizational infrastructure. The purpose of this paper is to explore the complexity of managing knowledge into practice, and in doing so reflect upon a range of strategies that will need to be considered in order to move from policy to practice.

Pre- and post-embedding methods are described that can be used for consecutive localization of two intracellular cytoplasmic binding sites in cells and tissues embedded in acrylic plastic for transmission electron microscopy. Both applications make use of the biotin-streptavidin system with colloidal gold detector particles and involve silver staining of the first gold signal to a predetermined size. Silver augmentation effectively masked any free binding sites on the biotinylated molecule and on the streptavidin complex of the first labelling reaction, thereby allowing a second cycle with the same detection system. Excellent ultrastructural localization was obtained with silver lactate as the silver ion donor in the developing solution, and the enhancement treatment did not destroy or even visibly reduce target site reactivity for the subsequently applied probe. Using these methods it was possible to achieve specific double lectin and immunological labelling; they could, however, be adapted to dual or multiple-labelling procedures with any biotinylated molecules.

With a few exceptions, the nature of the autoantigens targetted by autoimmune processes are largely unknown. The identification and precise biochemical characterization of these autoantlgens is (I) a first step in studies directed towards understanding the molecular basis of the diseases, (2) will allow the development of sensitive diagnostic immunoassays to the defined autoantlgens and (3) will provide an insight into the function of these molecules for the biology of the cell since target autoantlgens are highly conserved components. We have applied these principles to the study of autoimmune gastritis as a paradigm of organ-specific autoimmunity. We have identified 2 target autoantlgens with an apparent molecular weight of 60-90 KDa and 100 KDa localised to the secretory intracellular canallculi of gastric parietal cells. The 60-90 KDa component is specifically bound by tomato lectin suggesting that It contains poly N-acetyllactosamine sequences. We suggest that these molecules are components of, or accessory molecules associated with, the gastric proton pump.