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Norepinephrine triggers release of glial ATP to increase postsynaptic efficacy   总被引:10,自引:0,他引:10  
Glial cells actively participate in synaptic transmission. They clear molecules from the synaptic cleft, receive signals from neurons and, in turn, release molecules that can modulate signaling between neuronal elements. Whether glial-derived transmitters can contribute to enduring changes in postsynaptic efficacy, however, remains to be established. In rat hypothalamic paraventricular nucleus, we demonstrate an increase in the amplitude of miniature excitatory postsynaptic currents in response to norepinephrine that requires the release of ATP from glial cells. The increase in quantal efficacy, which likely results from an insertion of AMPA receptors, is secondary to the activation of P2X(7) receptors, an increase in postsynaptic calcium and the activation of phosphatidylinositol 3-kinase. The gliotransmitter ATP, therefore, contributes directly to the regulation of postsynaptic efficacy at glutamatergic synapses in the CNS.  相似文献   
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Assay of hexosaminidase A and B enzymes in four cases with developmental regression and cherry red spot on fundus examination confirmed that three cases had Tay-Sachs disease, and one case had Sandhoff disease. Prenatal diagnosis was carried out by hexosaminidase enzyme assay in amniotic fluid and cells in one family, and chorionic villus sample in the second family. The fetus was diagnosed to be unaffected in one, and affected in the other family. Assay of hexosaminidase A and B is useful for specific diagnosis of GM2 gangliosidosis, and for prenatal diagnosis to reduce the burden of these disorders.  相似文献   
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PURPOSE: Whole-body 18F-fluorodeoxyglucose ([18F]FDG) positron emission tomography (PET) imaging before and after induction therapy was prospectively evaluated in patients with esophageal cancer to determine whether changes in PET images could measure response to therapy. PATIENTS AND METHODS: Between April 1997 and April 1999, 39 patients (34 men and five women; median age, 59 years; range, 36 to 76 years) with esophageal cancer were prospectively enrolled in a single-institution clinical trial of staging, including PET, induction therapy, restaging including PET, and esophagectomy. All patients undergoing esophagectomy after induction therapy (n = 17) were followed either to recurrence, to death, or through a disease-free interval of at least 24 months. RESULTS: PET after standard staging studies and before therapy imaged undetected sites of metastatic disease in six patients (15%). Restaging (including PET) after induction therapy did not identify any patients with disease progression or any patients with loco-regionally unresectable disease at exploration. The median decrease in the standardized uptake value (SUV) during induction therapy was 59%. After R0 esophagectomy, the 2-year disease-free and overall survival was 38% and 63%, respectively, among patients who had a less than 60% decrease in SUV, and 67% and 89%, respectively, among patients who had a greater than 60% decrease in SUV (P =.055 and P =.088, respectively). CONCLUSION: Compared with conventional imaging, PET detects additional sites of metastatic disease at initial evaluation. After induction therapy, PET did not add to the estimation of loco-regional resectability and did not detect new distant metastases. However, changes in [18F]FDG PET may predict disease-free and overall survival after induction therapy and resection in patients with esophageal cancer. Further evaluation in larger trials is warranted.  相似文献   
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Secondary cutaneous dissemination from an orbital diffuse large B cell lymphoma has not been described before. The authors report an unusual case of anaplastic variant of diffuse large B cell lymphoma which primarily presented in the orbit and during the course of disease had subcutaneous dissemination.  相似文献   
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BackgroundPleomorphic Lobular Carcinoma in Situ (PLCIS) is a pathological variant of Lobular Carcinoma in Situ (LCIS) with distinct features. Since first described over a decade ago there are only few papers published about this condition.MethodsMedline and Pubmed based literature overview was done with the aim of describing the different histopathological, radiological and clinical features of this pathological entity to highlight the different clinicopathological presentations and modalities of treatment described.ResultsPLCIS has different biological features when compared to LCIS. It is more likely to be associated with invasive disease and the immuno-histochemical profile shows it is less likely to be ER and PR positive with higher positivity of HER2, Ki-67and p53. It has been suggested that PLCIS should be treated more aggressively than LCIS and surgically excised in similar fashion to DCIS.ConclusionPLCIS is a more aggressive variant of LCIS that needs to be managed differently. Surgical excision with clear margins is advised. Further adjuvant treatments have been described in the literature with little evidence to support their use.  相似文献   
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Background

Emergency departments see uniquely large numbers of patients across all demographic groups who are more likely to smoke and who attend with acute health concerns that can provide an impetus for behaviour change. Despite this potential opportunity, no smoking cessation programme in any UK emergency department yet exists. This study sought to identify perceived barriers and facilitators for emergency department smoking cessation activity, as well as potential modes of intervention, by exploring staff attitudes.

Methods

16 members of staff from the Emergency Department, Derby NHS Teaching Hospital were purposively sampled to include a spectrum of clinical and non-clinical roles, grades, and employment duration. Semi-structured interviews were conducted within the department, and thematically analysed with dual-coding for validity under an interpretivist paradigm.

Findings

Three themes were identified: roles of emergency departments, effects of smoking, and scope for intervention. Effects were described in individual-health and department-management contexts, with belief that reducing patient smoking would benefit both. Health promotion was seen as theoretically part of, and practically achievable within, the emergency department role. Lack of organisational support was a key barrier. Staff practice included occasional ad-hoc smoking cessation activity, but nothing routine. Those who did not incorporate smoking cessation into their practice felt that lack of training and support, rather than time, stopped them from doing so.

Interpretation

Support for emergency department smoking cessation was found in the face of major barriers. Options to address these barriers were suggested, highlighting a willingness to engage. Complex interventions appeared impractical, and no single approach seemed universally applicable to emergency department environments. This study addresses the paucity of evidence around emergency department attitudes towards smoking cessation by providing a unique and in-depth picture of staff in the study department. It also balances clinical and population health viewpoints and has potential to inform promising prevention strategies in the emerging population-focused health-care structures. However, the study might not be generalisable to other emergency departments. Further research exploring patient attitudes would be a valuable next step.

Funding

Health Education East Midlands.  相似文献   
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