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Mammalian retinas comprise a variety of interneurons, among which amacrine cells represent the largest group, with more than 30 different cell types each exhibiting a rather distinctive morphology and carrying out a unique function in retinal processing. However, many amacrine types have not been studied systematically because, in particular, amacrine cells with large dendritic fields, i.e. wide‐field amacrine cells, have a low abundance and are therefore difficult to target. Here, we used a transgenic mouse line expressing the coding sequence of enhanced green fluorescent protein under the promoter for choline acetyltransferase (ChAT‐EGFP mouse) and characterized a single wide‐field amacrine cell population monostratifying in layer 2/3 of the inner plexiform layer (WA‐S2/3 cell). Somata of WA‐S2/3 cells are located either in the inner nuclear layer or are displaced to the ganglion cell layer and exhibit a low cell density. Using immunohistochemistry, we show that WA‐S2/3 cells are presumably GABAergic but may also release acetylcholine as their somata are weakly positive for ChAT. Two‐photon‐guided patch‐clamp recordings from intact retinas revealed WA‐S2/3 cells to be ON‐OFF cells with a homogenous receptive field even larger than the dendritic field. The large spatial extent of the receptive field is most likely due to the extensive homologous and heterologous coupling among WA‐S2/3 cells and to other amacrine cells, respectively, as indicated by tracer injections. In summary, we have characterized a novel type of GABAergic ON‐OFF wide‐field amacrine cell which is ideally suited to providing long‐range inhibition to ganglion cells due to its strong coupling. 相似文献
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Frédéric Zubler Andreas Steimer Rebekka Kurmann Mojtaba Bandarabadi Jan Novy Heidemarie Gast Mauro Oddo Kaspar Schindler Andrea O. Rossetti 《Clinical neurophysiology》2017,128(4):635-642
Objective
Outcome prognostication in comatose patients after cardiac arrest (CA) remains a major challenge. Here we investigated the prognostic value of combinations of linear and non-linear bivariate EEG synchronization measures.Methods
94 comatose patients with EEG within 24 h after CA were included. Clinical outcome was assessed at 3 months using the Cerebral Performance Categories (CPC). EEG synchronization between the left and right parasagittal, and between the frontal and parietal brain regions was assessed with 4 different quantitative measures (delta power asymmetry, cross-correlation, mutual information, and transfer entropy). 2/3 of patients were used to assess the predictive power of all possible combinations of these eight features (4 measures × 2 directions) using cross-validation. The predictive power of the best combination was tested on the remaining 1/3 of patients.Results
The best combination for prognostication consisted of 4 of the 8 features, and contained linear and non-linear measures. Predictive power for poor outcome (CPC 3–5), measured with the area under the ROC curve, was 0.84 during cross-validation, and 0.81 on the test set. At specificity of 1.0 the sensitivity was 0.54, and the accuracy 0.81.Conclusion
Combinations of EEG synchronization measures can contribute to early prognostication after CA. In particular, combining linear and non-linear measures is important for good predictive power.Significance
Quantitative methods might increase the prognostic yield of currently used multi-modal approaches. 相似文献35.
Augusto Gallino Dai-Do Do Mario Alerci Iris Baumgartner Luca Cozzi Jeanne Marie Segatto Jacques Bernier Paolo Tutta Frauke Kellner Jürgen Triller Ernst Schneider Beatrice Amann-Vesti Gabriele Studer Kurt J?ger Markus Aschwanden Reto Canevascini Augustinus L Jacob Roger Kann Richard Greiner Felix Mahler 《Journal of endovascular therapy》2004,11(6):595-604
PURPOSE: To evaluate the effect of probucol and/or of endovascular brachytherapy (EVBT) on restenosis after percutaneous transluminal angioplasty (PTA) of femoropopliteal arteries. METHODS: A total of 335 patients (206 men; mean age 72+/-9 years) with intermittent claudication were randomized according to a 2x2 factorial design to 1 of the 4 groups: probucol, placebo, EVBT, and EVBT+probucol. Probucol (1 g/d) or placebo were given in double-blinded fashion 1 month before and for 6 months after PTA. Gamma irradiation (192Iridium, 14 Gy, 5-mm reference depth) was randomly applied in an unblinded manner from a noncentered endoluminal catheter. All patients received aspirin (100 mg/d). Primary endpoint was restenosis (>50% diameter reduction) detected by duplex ultrasound 6 months after PTA. Secondary endpoints included clinical and hemodynamic assessment. RESULTS: Restenosis in patients undergoing EVBT was 17% (23/133) versus 35% (50/142) in patients without EVBT (p<0.001); in patients treated with probucol versus placebo, the rates were 23% (31/135) and 30% (43/140, p<0.001). Three quarters (77%, 102/133) of patients were free of claudication after EVBT therapy versus 61% (87/142) without EVBT (p<0.05). Need for target vessel revascularization was 6% (8/133) with EVBT versus 14% (20/142) without EVBT (p<0.01). Late thrombotic occlusions occurred in 4% (6/133), exclusively in patients treated with EVBT after stent implantation. CONCLUSIONS: Endovascular brachytherapy significantly reduces restenosis, improves symptoms, and reduces reinterventions after PTA of femoropopliteal arteries. Probucol reduces restenosis but has no additive effect when combined with brachytherapy. 相似文献
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Urs Granacher Irene Wolf Anja Wehrle Stephanie Bridenbaugh Reto W Kressig 《Journal of neuroengineering and rehabilitation》2010,7(1):56
Background
Muscle fatigue and dual-task walking (e.g., concurrent performance of a cognitive interference (CI) while walking) represent major fall risk factors in young and older adults. Thus, the objectives of this study were to examine the effects of muscle fatigue on gait characteristics under single and dual-task conditions in young and older adults and to determine the impact of muscle fatigue on dual-task costs while walking. 相似文献37.
Christian E Oberkofler Philipp Dutkowski Reto Stocker Reto A Schuepbach John F Stover Pierre-Alain Clavien Markus Béchir 《Critical care (London, England)》2010,14(3):R117
Introduction
The impact of model of end stage liver disease (MELD) score on postoperative morbidity and mortality is still elusive, especially for high MELD. There are reports of poorer patient outcome in transplant candidates with high MELD score, others though report no influence of MELD score on outcome and survival. 相似文献38.
Spontaneous idiopathic acute spinal subdural hematomas are highly exceptional. Neurological symptoms are usually severe, and
rapid diagnosis with MRI is mandatory. Surgical evacuation has frequently been used therapeutically; however, spontaneous
recovery in mild cases has also been reported. We present a case of spontaneous recovery from severe paraparesis after spontaneous
acute SSDH, and review the English-speaking literature. 相似文献
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