Quantification of nimetazepam and its metabolite in human hair samples using liquid chromatography-tandem mass spectrometry: Case report.

Nimetazepam (marketed brand names; Erimin and Lavol) is an intermediate acting benzodiazepine derivative, which was widely used mainly in East and Southeast Asian region countries including Japan, Malaysia, Brunei, the Philippines, Thailand, Indonesia, Hong Kong, Singapore and China. Nimetazepam and its metabolite 7-aminonimetazepam were quantified from human hair samples by liquid chromatography tandem-mass spectrometry (LC-MS/MS), under selective reaction monitoring mode. Using diazepam-d5 as an internal standard, the concentration of nimetazepam and its metabolite 7-aminonimetazepam could be determined by matrix matched calibration method. Extraction of the target compounds was performed by using methanol, followed by evaporation and being concentrated with nitrogen. The Limit of quantification concentrations of nimetazepam and its metabolite 7-aminonimetazepam in hair samples were both 25 pg/mg by established method. The concentrations of nimetazepam in hair samples obtained from 2 users were 27.4, and 22.0 pg/mg, respectively; the concentrations of 7-animonimetazepam in hair samples were 54.2 and 29.1 pg/mg, respectively. In our study, the 7-aminonimetazepam concentrations in hair was higher than those of nimetazepam in the authentic hair samples. To our knowledge, this is the first report to establish the detailed procedure for quantificating nimetazepam and 7-aminonimetazepam in human hair by LC-MS/MS.

Interaction between Cd and Zn on Metal Accumulation, Translocation and Mineral Nutrition in Tall Fescue (Festuca arundinacea).

Tall fescue (Festuca arundinacea), an accumulator that is able to accumulate and excrete cadmium (Cd), has attracted much attention for its possible use in phytoremediation of heavy metal contaminated soils. In the present study, the interaction between Cd and Zn, and their uptake, translocation and accumulation under external Cd and Zn treatment in tall fescue were investigated. The concentrations of K, Ca, Mg in xylem sap under Cd and Zn treatment were measured to determine the level of mineral nutrients and their relationship with Cd alleviation. The result showed that Cd and Zn antagonized each other in the roots, while Cd antagonized Zn and Zn synergized Cd in the shoots of tall fescue. Compared with Cd only treatment, the concentrations of Ca, Mg and K in xylem sap increased after the addition of Zn, and they increased the most in the guttation. This result indicated that the addition of Zn facilitates the level of mineral elements to alleviate Cd toxicity, which might be used to improve the phytoremediation efficiency of Cd contaminated soils by tall fescue.

Soybean (Glycine max) prevents the progression of breast cancer cells by downregulating the level of histone demethylase JMJD5.

BACKGROUND: Breast cancer is the first noticeable disease in female patients. Long-term use of soybean (Glycine max) may prevent the progression of cancer. However, the molecular mechanism for the functions of soybean remains unclear. Histone demethylase JMJD5, an important epigenetic molecule, is overexpressed in the progression of breast cancer suggesting that soybean may ameliorate cancer by affecting the expression of JMJD5. MATERIALS AND METHODS: To test the hypothesis, human breast cancer cell lines MCF-7 and MDA-MB-231 were treated with different concentrations of soybean and/or transfected with the plasmids pcDNA3.1-JMJD5 and pTZU6 + 1-shRNA-JMJD5. The growth rate was measured using xCELLigence real-time cell analysis. The level of JMJD5 was measured by using quantitative reverse transcription-polymerase chain reaction and Western blot. RESULTS: Soybean showed significant inhibitory effects on the growth rates ofMCF-7 and MDA-MB-231 cells in a concentration-dependent way (P < 0.05). Meanwhile, the levels of JMJD5 were reduced with the increase of soybean concentration (P < 0.05). JMJD5 transfection increased the growth rates of MCF-7 and MDA-MB-231 by 25% and 40%. In contrast, the growth rates of MCF-7 and MDA-MB-231 cells were decreased by 17% and 23% after being transfected with JMJD5 shRNA. Soybean inhibited the growth rate of MCF-7 and MDA-MB-231 cells when they were transfected by JMJD5 gene but no for the cells transfected with JMJD5 shRNA. CONCLUSION: The complicated compositions of soybean will be beneficial to the therapy of breast cancer since its causes may be involved in multiple aspects. Soybean represses breast cancer development by downregulating the level of JMJD5.

Uptake, Distribution, and Transformation of CuO NPs in a Floating Plant Eichhornia crassipes and Related Stomatal Responses.

Engineered nanoparticles (NPs) are being released into aquatic environments with their increasing applications. In this work, we investigated the interaction of CuO NPs with a floating plant, water hyacinth (Eichhornia crassipes). CuO NPs (50 mg/L) showed significant growth inhibition on both roots and shoots of E. crassipes after 8-day exposure, much higher than that of the bulk CuO particles (50 mg/L) and their corresponding dissolved Cu2+ ions (0.30 mg/L). Scanning electron and light microscopic observations showed that the root caps and meristematic zone of E. Crassipes were severely damaged after CuO NP exposure, with disordered cell arrangement and a destroyed elongation zone of root tips. It is confirmed that CuO NPs could be translocated to shoot from both roots and submerged leaves. As detected by X-ray absorption near-edge spectroscopy analysis (XANES), CuO NPs were observed in roots, submerged leaves, and emerged leaves. Cu2S and other Cu species were also detected in these tissues, providing solid evidence of the transformation of CuO NPs. In addition, stomatal closure was observed during CuO NPs-leaf contact, which was induced by the production of H2O2 and increased Ca level in leaf guard cells. These findings are helpful for better understanding the fate of NPs in aquatic plants and related biological responses.