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Adrenaline (AD) is important in information transmission through the human central nervous system. Considering the significant biochemical functions of AD, the development of electrochemical sensors capable of detecting AD levels in living organisms has attracted considerable interest. In this study, AD was detected using electrochemical sensors developed based on Au nanoparticles/ionic liquids/N‐ and P‐co‐doped carbon nanotubes‐modified carbon cloth (AuNPs/ILs/N,P‐MWCNTs/CC) electrodes. AuNPs/ILs/N,P‐MWCNTs/CC composites were prepared on carbon cloth (CC) substrates using ionic liquids (ILs), N‐ and P‐co‐doped multi‐walled carbon nanotubes (N,P‐MWCNTs), and Au nanoparticles (AuNPs) as modified materials. The effects of pH and scanning speed were optimized and tested on the prepared composites. The results of cyclic voltammetry (CV) and differential pulse voltammetry (DPV) experiments showed that the modified ILs, N,P‐MWCNTs, and AuNPs effectively improved the oxidation performance of AD. In addition, the linear range obtained from the DPV scans of the AuNPs/ILs/N,P‐MWCNTs/CC composite material was 30–505 μmol/L, with a detection limit of 0.31 μmol/L. The fabricated sensors have good sensitivity (6.9 μA·mM−1·cm−2) for AD of 30–505 μM. Therefore, the electrochemical sensing method based on the AuNPs/ILs/N,P‐MWCNTs/CC composite material is a promising and reliable AD detection technology that also exhibits good selectivity in the presence of interfering substances such as folic acid and ibuprofen. In practical applications, this material can help realize real‐time AD detection to determine whether athletes use doping and other illegal drugs before competitions and to perform synchronous detection. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of proanthocyanidins(PC) induced by amyloid-beta peptide(Aβ25-35) in human neuroblastoma cell line SH-SY5Y and its possible mechanism. Methods SH-SY5Y cells were exposed to Aβ25-35 to establish a cell injury model in vitro. PC and(or) secretory protein Dickkopf-1 (Dkk1), the endogenic inhibitor of Wnt/β-catenin signaling pathway were used for intervention. The cells were divided into control group, Aβ25-35 group, PC(different concentrations)+Aβ25-35 groups, Dkk1 group, Dkk1+ PC+Aβ25-35 group.The cell viability was evaluated by MTT assay. The expressions of β-catenin, GSK-3β, p-GSK-3β were measured by Western blot. The secreted Aβ1-42 was detected by ELISA. Results Compared with the control group, the cell viability, the expression of β-catenin and p-GSK-3β were reduced in Aβ25-35 treated group(P＜0.05), while the secreted Aβ1-42 was increased (P＜0.05). PC improved the cell viability, increased the expression of β-catenin and p-GSK-3β, and reduced the secreted Aβ1-42 in SH-SY5Y cells induced by Aβ25-35 (P＜0.05). After using Dkk1,the ability of PC was decreased on the enhancement of β-catenin expression, the improvement of p-GSK-3β expression, and the reduction of the secreted Aβ1-42 (P＜0.05). Conclusions PC may decrease Aβ1-42 secretion in SH-SY5Y cells induced by Aβ25-35 through Wnt/β-catenin signaling pathway.

Abstract Background Ginsenoside Rg3, a saponin extracted from ginseng, inhibits angiogenesis. The combination of low-dose chemotherapy and anti-angiogenic inhibitors suppresses growth of experimental tumors more effectively than conventional therapy or anti-angiogenic agent alone. The present study was designed to evaluate the efficacy of low-dose gemcitabine combined with ginsenoside Rg3 on angiogenesis and growth of established Lewis lung carcinoma in mice. Methods C57L/6 mice implanted with Lewis lung carcinoma were randomized into the control, ginsenoside Rg3, gemcitabine and combination group. The quality of life and survival of mice were recorded. Tumor volume, inhibitive rate and necrosis rate were estimated. Necrosis of tumor and signals of blood flow as well as dynamic parameters of arterial blood flow in tumors such as peak systolic velocity (PSV) and resistive index (RI) were detected by color Doppler ultrasound. In addition, expression of vascular endothelial cell growth factor (VEGF) and CD31 were observed by immunohistochemstry, and microvessel density (MVD) of the tumor tissues was assessed by CD31 immunohistochemical analysis. Results Quality of life of mice in the ginsenoside Rg3 and combination group were better than in the control and gemcitabine group. Combined therapy with ginsenoside Rg3 and gemcitabine not only enhanced efficacy on suppression of tumor growth and prolongation of the survival, but also increased necrosis rate of tumor significantly. In addition, the combination treatment could obviously decrease VEGF expression and MVD as well as signals of blood flow and PSV in tumors. Conclusion Ginsenoside Rg3 combined with gemcitabine may significantly inhibit angiogenesis and growth of lung cancer and improve survival and quality of life of tumor-bearing mice. The combination of chemotherapy and anti-angiogenic drugs may be an innovative and promising therapeutic strategy in the experimental treatment of human lung cancer.

Point-of-care test (POCT) is a necessary technology to implement the supervision of genetically modified (GM) crops in resource-limited settings, which plays an important role in GM organisms monitoring. Recently, biosensor provides a promising pathway for a simple, quick and affordable quantification of GM ingredients. So far plenty of studies have concentrated on the methodology development of biosensor, however its application has rarely been reported. The development of portable biosensors with desirable characteristics of integration and miniaturization is highly demand for POCT. This paper reviews recent advances in handheld device--assisted miniaturized biosensor systems for POCT of GM crops. Miniaturization strategies of biosensors for POCT of GM organisms in the future are then proposed. The trends, prospects and challenges of miniaturized biosensors for POCT are further described. [ABSTRACT FROM AUTHOR]

Abstract: The gas-phase reactions of fluorocarbon compounds CH4– n F n (n =1–3) with Pt (3D, 1S) have been systematically explored via density functional theory (DFT) in order to investigate the mechanisms of these reactions. The results indicate that a reaction of CH3F with Pt (3D, 1S) experiences a rearrangement process to generate counterintuitive production (CH2F−PtH). CH2F2 and CHF3 activation by Pt (3D, 1S) yields high-oxidation-state complexes with carbon–metal double bonds. Moreover, the attack of platinum atoms on fluorine atoms in different fluorocarbon compounds involves intersystem crossing (ISC) between triplet and singlet state Potential Energy Surfaces (PESs). The crossing points (CPs) have been located by the intrinsic reaction coordinate (IRC) approach used by Yoshizawa et al. and corresponding minimum energy crossing points (MECPs) obtained by the mathematical algorithm proposed by Harvey et al. have also been used. Additionally, possible spin inversion processes are discussed using spin–orbit coupling (SOC) calculations. [ABSTRACT FROM AUTHOR]

Abstract: The mechanisms of the reaction between N2O and CO catalyzed by MO+ (M=Ru, Os) have been investigated using the density functional theory (DFT). The potential energy surfaces, the crossing points and the corresponding minimum energy crossing points have been explored. The probability of hopping in the vicinity of the crossing has been calculated by the Landau–Zener-type model. The results indicate the reactions are O-atom abstraction mechanism for the catalysts RuO+ and OsO+. The large probability value shows the intersystem crossing occurs efficiently, which makes the reaction access to a lower energy pathway and accelerate the reaction rate. [ABSTRACT FROM AUTHOR]