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BACKGROUND: Currently, no biochemical assay involving gingival crevicular fluid is utilized routinely as a screening test for periodontal disease. OBJECTIVE: The objective of the present study was to evaluate the potential of gingival crevicular fluid assay as a screening methodology. METHODS: The subject population was comprised of 27 volunteers. Nine participants were classified as 'subject with periodontal destruction' (SPD) exhibiting at least one site with pocket depth and attachment loss>3.5 mm, whereas the remaining individuals were categorized as 'subject with minimal periodontal destruction' (SMD). Gingival crevicular fluid was collected from fixed sites via a standardized method. Biochemical assays of 12 substances (hemoglobin, albumin, transferrin, alpha(1)-antitrypsin, fibronectin, IgA, IgG, IgM, lactoferrin, myeloperoxidase and neutrophil elastase) were conducted at a commercial laboratory. Power transformation of total quantities in gingival crevicular fluid was performed for statistical analysis. RESULTS: Relationships between total quantity of each substance and periodontal disease status were unclear. Logistic regression analysis yielded six predictive models, which consisted of substance pairs: neutrophil elastase/IgA, neutrophil elastase/hemoglobin, neutrophil elastase/alpha(1)-antitrypsin and neutrophil elastase/IgG, and IgA/albumin and IgA/transferrin (p<0.05). Regression lines for SPD and SMD on a scattergram of IgA and neutrophil elastase were nearly parallel within the range of amounts in gingival crevicular fluid. The predictive model derived from both substances afforded sensitivity and specificity of 88% and 94%, respectively. CONCLUSIONS: These results indicated that the combination of IgA and neutrophil elastase in gingival crevicular fluid may be crucial for prediction of periodontal disease status. Furthermore, these data suggested that biochemical assays employing both substances in gingival crevicular fluid may provide a satisfactory screening test for periodontal disease.  相似文献   
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Annals of Nuclear Medicine - Amyloid positron emission tomography (PET) can reliably detect senile plaques and fluorinated ligands are approved for clinical use. However, the clinical impact of...  相似文献   
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Annals of Nuclear Medicine - Although previous studies have investigated age and gender effects on striatal subregional dopamine transporter (DaT) binding, these studies were mostly based on a...  相似文献   
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Dynamic activity of glia has repeatedly been demonstrated, but if such activity is independent from neuronal activity, glia would not have any role in the information processing in the brain or in the generation of animal behavior. Evidence for neurons communicating with glia is solid, but the signaling pathway leading back from glial-to-neuronal activity was often difficult to study. Here, we introduced a transgenic mouse line in which channelrhodopsin-2, a light-gated cation channel, was expressed in astrocytes. Selective photostimulation of these astrocytes in vivo triggered neuronal activation. Using slice preparations, we show that glial photostimulation leads to release of glutamate, which was sufficient to activate AMPA receptors on Purkinje cells and to induce long-term depression of parallel fiber-to-Purkinje cell synapses through activation of metabotropic glutamate receptors. In contrast to neuronal synaptic vesicular release, glial activation likely causes preferential activation of extrasynaptic receptors that appose glial membrane. Finally, we show that neuronal activation by glial stimulation can lead to perturbation of cerebellar modulated motor behavior. These findings demonstrate that glia can modulate the tone of neuronal activity and behavior. This animal model is expected to be a potentially powerful approach to study the role of glia in brain function.  相似文献   
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Osteoprotegerin is a circulating osteoclastogenesis inhibitory factor and serum osteoprotegerin levels are elevated in hemodialysis patients. This study investigated whether osteoprotegerin levels correlated with various clinical parameters in hemodialysis patients. The subjects were 45 men and 37 women aged from 27 to 94 years (mean = 60.4 +/- 13.9 years), and the duration of dialysis was 9-277 months (mean = 89.5 +/- 64.7 months). Serum osteoprotegerin levels were measured by enzyme-linked immunosorbent assay. Data were analyzed by stepwise multiple regression analysis. The mean osteoprotegerin level of the hemodialysis patients was 303 +/- 210 pg/mL, which was higher than in age-matched healthy controls. Osteoprotegerin levels increased with age, a longer duration of dialysis, and the presence of diabetes. Skeletal resistance to parathyroid hormone might be increased by aging, a long dialysis period, and diabetes, perhaps explaining why adynamic bone disease is more common in older or diabetic patients.  相似文献   
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