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• The upconversion luminescence performance of UCNPs was regulated. • The effect of silica shell thickness on ET in UCNPs was studied. • The effect of surface charge with silica shell on ET in UCNPs was explored. Lanthanide-doped upconversion nanoparticles (UCNPs) can convert near-infrared light into visible light emission, and have attracted more and more interests due to their great potential in ultrasensitive biosensors. However, it is still a huge challenge to manipulate the intensity ratio between different emission lines and realize the modulated up-conversion. In this work, the upconversion luminescence performance of UCNPs was regulated by coupling with Au nanorod-silicon core–shell (AuNR@SiO 2) nanostructures. By changing the thickness and surface charge of the silica shell, the influence of the thickness and surface charge on the energy transfer of the UCNPs was explored. It is expected that the up-conversion luminescence effect of this composite nanostructure regulated by plasmons can provide a basis for the extensive exploration of biological detection and sensing applications. [ABSTRACT FROM AUTHOR]

A novel method was developed for the analysis of monoamine neurotransmitters (MNTs) in human urine by carrier-mediated liquid-phase microextraction based on solidification of stripping phase method (CM-LPME-SSP) coupled with high performance liquid chromatography-electrochemical detector (HPLC-ECD). By adding an appropriate carrier in organic phase, simultaneous extraction of hydrophilic analytes, MNTs, with high enrichment factors (22.6–36.1 folds) and excellent sample cleanup was achieved. A new strategy, solidifying the aqueous stripping phase in the back-extraction process, was developed to facilitate the collection of the stripping phase as small as a few microliters. Combined with HPLC-ECD analysis, the linear ranges of the established method were 0.015–2.0 μg/mL for NE, E, DA, and 0.020–2.0 μg/mL for 5-HT. The limits of detection and quantification were in the range of 5.5–10.8 ng/mL and 15–20 ng/mL, respectively. The relative recoveries were in the range of 87–108%, with intraday and interday relative standard deviations lower than 13%. This method was successfully applied to analysis of MNTs in real urine. [ABSTRACT FROM AUTHOR]

Solvothermal reaction of 4,4',4'-nitrilotribenzoic acid (H3TCA) with Ca(NO3)2·4H2O and Cd(NO3)2·4H2O successfully afforded a heterometallic compound, that is, [Cd2Ca(TCA)2(DMA)2(H2O)3]n·2n(DMA) (1, DMA = N,N'-dimethylacetamide). The structure of 1 was further characterized through EA, diffraction of single crystal X-ray, and thermogravimetric analysis (TGA) together with powder X-ray diffraction (PXRD). Moreover, complex 1's luminescent performance in solid state was also discussed at environmental temperature. The applications on the ischemic cerebral infarction therapy were evaluated, and the specific mechanism was investigated at the same time. Firstly, the hypersensitivity C-reactive protein (hs-CRP) content in human brain microvascular endothelial cell (HBMEC) was measured with real-time reverse transcription-polymerase chain reaction (RT-PCR). Then, interleukin-18 and interleukin-1β content released through the HBMEC was detected with enzyme-linked immunosorbent assay (ELISA). [ABSTRACT FROM AUTHOR]

This work was aimed to study the risk factors and prognostic treatment for acute ischemic stroke (AIS) patients with early neurological deterioration (END) after intravenous thrombolytic therapy via compressed sensing algorithm-based magnetic resonance imaging (CS-MRI). 231 patients who were diagnosed with AIS were selected, and the final involved number of patients was 182. Patients with AIS were treated with intravenous thrombolysis with alteplase within 4.5 hours of onset. After treatment, patients with early neurological deterioration were defined as the deteriorating group and those without early neurological impairment were defined as the nondeteriorating group. In univariate analysis, hypertension, white blood cell count, and National Institutes of Health Stroke Scale (NIHSS) score were correlated with the occurrence of END. Under the CS-MRI theory, the two groups of patients were evaluated for middle cerebral artery basal ganglia infarction and internal watershed infarction. After univariate analysis, the P < 0.1 variables were taken as the independent variable, and the binary logistic regression model was adopted for multivariate regression analysis. It was disclosed that NIHSS score was not correlated with the occurrence of early neurological function deterioration, while homocysteine was. Hypertension, white blood cell count, homocysteine, and NIHSS score were risk factors for END. The image analysis revealed that the incidence of deteriorating basal ganglia infarction group was lower relative to the nondeteriorating group, and the incidence of watershed infarction was higher in the deteriorating group versus the nondeteriorating group. The image analysis suggested that predicting the occurrence of END through risk factors can actively provide endovascular treatment for patients with AIS. [ABSTRACT FROM AUTHOR]