Determination of hyperoside and isoquercitrin in rat plasma by membrane-protected micro-solid-phase extraction with high-performance liquid chromatography.

A novel method, micro-solid-phase extraction based on membrane-protected molecularly imprinted polymer, was developed to extract hyperoside and isoquercitrin in rat plasma. Synthesized hyperoside MIPs were packed in a porous polyether sulfone membrane envelope to perform extraction. The parameters sorbent materials, membrane types, extraction time and desorption conditions were optimized for micro-solid-phase extraction. Under the optimal conditions, correlation coefficients, 0.998 and 0.999, were obtained for hyperoside and isoquercitrin, respectively, with the linear range between 1 and 120 µg/mL. The absolute extraction recoveries from 84.5 to 89.3% were found. The method detection limits of hyperoside and isoquercitrin were 0.24 and 0.22 µg/mL, respectively. Compared with traditional methods, solid-phase extraction, liquid-liquid extraction and protein precipitation, the developed method was simple, highly efficient for extraction, environmentally friendly, and particularly suitable for complex biological samples.

An electrochemical Hg2+ sensor based on signal amplification strategy of target recycling.

In this work, an unmodified homogeneous electrochemical sensor based on electrochemical bonding and catalytic hairpin assembly (CHA) was first constructed for the high sensitivity detection of Hg2+. Herein, tetraferrocene, a synthesized compound, was used as a signal marker that modified both ends of the hairpin probe to amplify the electrochemical signal. The interaction of T-Hg2+-T could induce the catalytic self-assembly of hairpins by means of auxiliary DNA. The rigid DNA triangle that was formed easily reaches the electrode and induced Au-S self-assembly assisted by potential, allowing tetraferrocene to reach the electrode surface and generate a sensitive electrochemical signal. CHA and tetraferrocene signal markers accomplished dual signal amplification, and the limit of detection was 0.12 pM. Differential pulse voltammetry experiments in the presence of tetraferrocene redox indicator show that the linear response range of electrochemical biosensors to mercury ions is 0.2-2000 pM, This technology offers good selectivity and high recognition efficiency for the detection of mercury ions and has broad application prospects in actual sample detection.

[The spectroscopy analysis of intermolecular interaction between the template molecule and functional monomer before polymerization].

To prepare the non-covalent molecularly imprinted polymers (MIPs) with good adsorption properties,the degree of interaction is important factor between the template molecule and functional monomer before polymerization. The correlative research has been reported less. In the present paper, UV combined with infrared spectra was applied to study intermolecular interaction of the template molecule and functional monomer. andrographolide was used as the template molecule, acrylamide (AM) as the functional monomer in the three kinds of solvents, namely acetonitrile, tetrahydrofuran and ethyl acetate. The experimental results showed that the UV absorption peaks at 224 nm exhibited blue-shift of 5 nm, and the absorption peak increased for andrographolide and AM in acetonitrile solvent. In IR spectra, the O--H stretching vibration was also blue-shifted by nearly 8 cm(-1), while the N--H stretching vibration of blue shift was about 6 cm(-1). The data showed that the strong interaction of blue-shifted hydrogen bonds generated between the molecules of andrographolide and AM. And intermolecular interaction was very weak in other two solvents. It is obvious that the stronger the intermolecular interaction, the greater the spectroscopy changes, the better the selectivity of identification points, and thus the better the adsorption properties of MIPs are.

Randomized double-blind multicentre placebo-controlled clinical trial of the clonidine adhesive patch for the treatment of tic disorders.

OBJECTIVE: The aim of the present study was to evaluate the therapeutic effectiveness and safety of the clonidine adhesive patch in treating tic disorders. METHOD: A total of 437 patients, who met Chinese Classification of Mental Disorders-third edition diagnostic criteria for transient tic disorder (5%), chronic motor or vocal tic disorder (40%) or Tourette disorder (55%), aged 6-18 years, were divided randomly into an active treatment group and a clinical control group. Participants in the active treatment group were treated with a clonidine adhesive patch and participants in the clinical control group with a placebo adhesive patch for 4 weeks. The dosage of the clonidine adhesive patch was 1.0mg, 1.5mg or 2.0mg per week, depending on each participant's bodyweight. Participants whose Yale Global Tic Severity Scale (YGTSS) score decreased <30% and Clinical Global Impression score was > or =4 by the end of week 3 were withdrawn from the trial. RESULTS: After 4 weeks of treatment the active treatment group participants' YGTSS score was significantly lower than that of the clinical control group (F=4.63, p=0.03). Further, the active treatment group had a significantly better therapeutic response than the clinical control group (chi(2)=9.15, p=0.003). The response rate in the active treatment group was 68.85% compared to 46.85% in the clinical control group (chi(2)=16.98, p=0.0001). The rate of adverse events was low (active treatment group, 3.08%; clinical control group, 7.21%) and did not differ between the two groups. CONCLUSIONS: The clonidine adhesive patch is effective and safe for tic disorders.

[A multicenter controlled study on aripiprazole treatment for children with Tourette syndrome in China].

OBJECTIVE: To evaluate the efficacy and safety of aripiprazole in the treatment of children with Tourette syndrome. METHOD: A prospective, multi-center, controlled clinical trial was conducted in 195 children aged 5-17 years with Tourette syndrome. The patients were assigned to two groups: aripiprazole group (n=98) and tiapride group (n=97), with the treatment dosage of 5-25 mg/d and 100-500 mg/d, respectively. After 12 weeks treatment, the clinical efficacy was assessed by the Yale Global Tic Severity Scale (YGTSS) score, and adverse reactions were observed by side effects symptoms scale, blood biochemical indexes, and electrocardiography. RESULT: Significant pre- and post-treatment differences were ascertained for motor tic, phonic tic, function damage and total scores of YGTSS in the both groups from the second week of treatment (P<0.0001). Compared with the tiapride group, the aripiprazole group showed a more significantly decreased function damage score of YGTSS by the second week of treatment (P<0.05). After 12 weeks treatment, total scores of YGTSS in the aripiprazole group decreased from 53.74±15.71 at baseline to 24.36±16.38, while in the tiapride group from 51.66±13.63 to 23.26±15.31. The mean reduction scores of YGTSS were 29.38 in the aripiprazole group and 28.40 in the tiapride group at the end of treatment, and the clinical response rates were 60.21% and 63.92%, respectively. There were no significant differences between the 2 groups (P>0.05). The incidence of adverse reactions was similar in the aripiprazole and tiapride groups, with 29.6% and 27.8% respectively. There were no significant differences in the incidence of adverse reactions between aripiprazole and tiapride groups and no severe adverse events were found in either group. CONCLUSION: The results showed that aripiprazole showed similar therapeutic effect to tiapride in treatment of children with Tourette syndrome. Aripiprazole was safe and well tolerated in Chinese population, and can be considered as a new valid option for the treatment of tic disorders.