Determination of Methamphetamine by High-Performance Liquid Chromatography in Odor-Adsorbent Material Used for Training Drug-Detection Animals.

The objective of the present report was to develop and validate a simple, sensitive, and selective analytical method for the determination of methamphetamine in an odor-adsorbent material (gauze) which was used to improve and standardize the training method used for drug-detection animals. High-performance liquid chromatography (HPLC) was performed using a Spherisorb ODS2 C18 column (200 mm × 4.6 mm, 5 µm), with a mobile phase consisting of a 0.25% methanol/triethylamine aqueous solution (V:V = 20:80), the pH of which was adjusted to 3.1 using glacial acetic acid, at a flow rate of 1.0 mL/min. The column temperature was 25 °C, and the detection of the analytes was performed at a wavelength of 260 nm. Methamphetamine showed good linearity (R2 = 0.9999) in the range of 4.2~83.2 mg/mL. The stability of the test material was good over 24 h. The precision of the method was good, with an average spiked recovery of 86.2% and an RSD of 2.9%. The methamphetamine content in the gauze sample was determined to be 7.8 ± 2.2 µg/sample. A high-performance liquid chromatography (HPLC) method was optimized and validated for the determination of methamphetamine in adsorbent materials (gauze). Validation data in terms of specificity, linearity, the limit of detection and the limit of quantification, reproducibility, precision, stability, and recovery indicated that the method is suitable for the routine analysis of methamphetamine in adsorbent materials (gauze) and provided a basis for training drug-detection animals.

Sodium propionate improves cognitive and memory function in mouse models of Alzheimer's disease.

This study was designed to explore whether sodium propionate (SP) alleviates cognitive damage in a mouse model of Alzheimer's disease (AD). We evaluated behavioral and biochemical aspects in an animal model of AD made by intracerebroventricular injection of Aß1-42 peptide. Two-month-old ICR mice were treated with SP or normal saline for 21 days (control group, Aß1-42 group, Aß1-42 + SP50 mg/kg group, Aß1-42 + SP100 mg/kg group, and Aß1-42 + SP200 mg/kg group). Behavioral tests showed that SP alleviated cognitive and memory impairments in AD mice. Moreover, SP treatment significantly suppressed the level of inducible nitric oxide synthase (iNOS) in the hippocampus. Concomitantly, the overexpression of interleukin-1α (IL-1α), interleukin-1ß (IL-1ß) and interleukin-6 (IL-6) in the hippocampus induced by Aß1-42 was significantly reduced following treatment with SP. In addition, SP was able to increase the levels of synaptophysin (SYN) and postsynaptic dense protein 95 (PSD95). Our study shows that SP could significantly improve Aß1-42-induced spatial learning and memory impairment by reducing neuroinflammation via inhibition of proinflammatory cytokines and iNOS activation and restoring synapse plasticity by increasing synaptically associated protein levels, suggesting that SP has a positive effect and potential for AD therapies.

Verification of a multi-function closed maze for the detection of affective disorder and spatial cognitive impairment in post-weaning socially isolated rats.

OBJECTIVE: To verify a behavioral device for the detection of learning, memory, and affective disorders in post-weaning socially isolated rats. METHODS: We tested the behavioral changes in post-weaning socially isolated rats using a multi-function closed maze, a self-developed behavioral device, against the classical mood disorder detection method, the IntelliCage system and Morris water maze. RESULTS: In the multifunctional closed maze experiment, the spatial learning and memory ability of post-weaning socially isolated rats decreased, which was consistent with the results of the water maze and IntelliCage system. Furthermore, the behavioral changes in the post-weaning socially isolated rats in the multi-function closed maze test were the same as those of the forced swimming and open field tests, indicating that the rats had depression- and anxiety-like behaviors. CONCLUSION: A multi-function closed maze can detect emotional changes, spatial learning ability, and memory ability.