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A novel electrochemical sensor was established based on graphene-wrapped PtNi nanoparticles supported on three-dimensional (3D) N-doped porous carbon (G-PtNi/3D-NPC) for the highly sensitive and selective detection of carbendazim (CBZ). In this sensing system, the encapsulation of PtNi nanoparticles (NPs) by graphene can effectively prevent the aggregation tendency and enhance the structural stability. The hierarchically porous nanostructures have a large specific surface area to expose a large number of active sites and the resulting enhanced electrical conductivity ultimate improves the electrocatalytic activity towards CBZ. Under the optimal conditions, the prepared sensor showed excellent electrochemical responses for the determination of CBZ with a linear range of 0.5-30 µM and lower limit of detection (LOD) of 0.04 µM (S/N = 3). It also shows excellent anti-interference ability at a working potential of 0.74 V. The feasibility of the senor is demonstrated for its practical assays in diluted peach and vegetable samples with acceptable recovery (95.8-97.3 %, peach; 97.2-97.6 %, vegetable) and a relative standard deviation (RSD) below 2.3%.
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The active-vision-based reconstruction is an advanced approach to characterize the spatial object. In the active vision, the planar laser is a kind of the moderate structured light for the robustness and adaptivity in the complicated illumination environment. However, as the planar laser is determined by 3 unknown degrees of freedom, the laser sensor should be calibrated in the immovable coordinate frame of reference (CFR), or be pre-calibrated in the coordinate frame of the camera (CFC) and moved with CFC. In the study, as the main improvement, the laser plane is attached to the simple 2D reference without strict constraints of the relative installation position and posture. The laser plane is desired to be flexibly moved and registered in CFC. The calibration is modeled by the closed loop of the camera, the cylindrical object, the planar laser and the 2D reference, in which the camera is twice considered as the bridge between the cylindrical object and the 2D reference. The calibration contributes the planar laser that is determined as a constant vector in CFR. Furthermore, the reconstruction is performed by the calibrated laser plane and refined by the optimization method. The method errors of 1.263, 1.517, 1.633, and 1.803 mm are evaluated by the experiments, which indicate the flexibility of the method and applicable prospects in the spatial reconstruction field.
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BACKGROUND: A decreased plasma level of soluble form of the receptor for advanced glycation end products (sRAGE) in patients with Alzheimer's disease (AD) has been reported. However, no evidence has shown whether the sRAGE plasma level of AD patients may differentiate from other types of dementia. METHODS: Our study assessed sRAGE concentrations in the following 121 individuals in Chongqing area: 36 patients with AD, 12 with vascular dementia (VaD), 14 with mixed dementia (MD), 24 with other dementia (OD) including Parkinson's disease dementia, frontotemporal dementia, paralytic dementia and 35 cognitively normal controls. The total plasma level of sRAGE was determined using sandwich ELISA method. RESULTS: sRAGE concentration in AD is significantly decreased compared with healthy controls. However, the receiver operating characteristic curve analysis of sRAGE between the AD and the control shows a low diagnostic accuracy. CONCLUSIONS: Our results demonstrate that sRAGE may assist the diagnosis of AD from normal individuals, but cannot differentiate AD from VaD, MD or OD.
Asunto(s)
Enfermedad de Alzheimer/sangre , Productos Finales de Glicación Avanzada/sangre , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Demencia Vascular/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Curva ROC , Análisis de RegresiónRESUMEN
Objective: Lingual lymph node (LLN) metastasis is regarded as an indicator of unfavorable prognosis and a crucial sign of the high degree of primary tumor aggressiveness. However, detecting LLN metastasis is an important but frequently overlooked aspect of diagnosis and surgical treatment planning. The study aims to identify LLNs by intraoperative near-infrared (NIR) fluorescence imaging with indocyanine green absorbed into human serum albumin (ICG: HSA) and describe the presence of lymphatic drainage channels from the floor of the mouth in patients with tongue carcinoma. Materials and Methods: 21 patients diagnosed with cT1-T4 squamous cell carcinoma (SCC) of the tongue margin and scheduled to undergo tumor resection and unilateral neck dissection were enrolled. After exposing the neck, the patients were injected with 0.3 ml of ICG: HSA (500 µM) in three quadrants around the tumor, excluding the mucous membrane of the basal region cavity. Employing a near-infrared fluorescence imaging system, the fluorescence of levels I, II, III, and IV was measured during neck dissection. Results: LLNs were detected in four patients and were identified as metastatic LLNs in all 21 patients. The near-infrared fluorescence imaging system showed the existence of lymphatic drainage channels in the floor of the mouth. In patients receiving peritumoral injection of ICG: HSA, the mean fluorescence intensity (MFI)of metastatic lymph nodes (LNs) (178.4 ± 64.39, mean ± SD) was higher than that in non-metastatic LNs (132.0 ± 76.5, mean ± SD) (p < 0.05). Conclusion: NIR fluorescence imaging with ICG: HSA could be used for intraoperative identification of LLNs and assist in the determination of metastatic lymph nodes for tongue carcinoma patients. Additionally, this finding demonstrates the feasibility of near-infrared fluorescence imaging in defining lymphatic drainage channels in the head and neck.