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As important secondary plant metabolites, naphthoquinones exhibit a wide range of biological activities. However, their potential as sustainable alternatives to synthetic acaricides has not been studied. This study for the first time investigates the acaricidal activity of naphthoquinones against Psoroptes cuniculi in vitro. Furthermore, the in vivo activity, the skin irritation effects, the cytotoxicity and the inhibitory activities against mite acetylcholinesterase (AChE) and glutathione S-transferase (GST) of the two compounds that displayed the best insecticidal activity in vitro were evaluated. Among fourteen naphthoquinones and their analogs, juglone and plumbagin were observed to possess the strongest acaricidal activities against P. cuniculi with LC50 values of 20.53 ppm and 17.96 ppm, respectively, at 24 h. After three treatments, these two chemicals completely cured naturally infested rabbits in vivo within 15 days, and no skin irritation was found in any of the treated rabbits. Compared to plumbagin, juglone presented no or weak cytotoxicity against HL-7702 cells. Moreover, these two chemicals significantly inhibited AChE and GST activity. These results indicate that juglone has promising toxicity against P. cuniculi, is safe for both humans and animals at certain doses, and could be used as a potential alternative bio-acaricide for controlling the development of psoroptic mange in agricultural applications.
The comparative study of bloodletting therapy between traditional Chinese medicine and Tibetan medicine in view of history development, theoretic basis, bloodletting location, bloodletting tool, operation method, bloodletting amount, indications, contraindications and the others are conducted in this paper. It is pointed out that the bloodletting therapy could be better carried forward and developed through the interaction and integration of bloodletting therapy between traditional Chinese medicine and Tibetan medicine in term of the theoretic, practical and development patterns under the guidance of these two different medical theoretical systems.
A pair of stable isotope labeling (SIL) reagents, <b>N</b>-(4-(carbazole-9-yl)-phenyl)-<b>N</b>-maleimide (NCPM-d0) and its heavy analogue NCPM-d2, were used for labeling thiol-containing drugs. On basis of SIL, a global isotope internal standard quantitative method for the detection of five thiol-containing drugs by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed. The NCPM-d0 and NCPM-d2 can easily label thiol-containing drugs under mild conditions within 10 min at 40 °C. The NCPM-d0 and NCPM-d2 labeled thiol-containing drugs can generate two characteristic product ions (<b>m</b>/<b>z</b> at 372.5 and 374.5) under collision induced dissociation, respectively, which is used to establish the multiple reaction monitoring (MRM) based detection. The NCPM labeling combined with MRM analysis not only allowed trace detection of thiol-containing drugs due to the extremely high sensitivity, but also efficiently corrected the matrix effects during HPLC-MS/MS and the instrument fluctuation in the MS/MS signal intensity. The detection sensitivities of thiol-containing drugs improved by 14.5-650.5-fold due to NCPM-labeling, while the matrix and ion suppression effects were markedly minimized by the SIL strategy. The limits of detection (LODs) and the limits of quantitation (LOQs) were in the range 10.0-15.0 ng·mL−1 and 31.0-50.0 ng·mL−1, respectively. The proposed method was used for the simultaneous determination of five thiol-containing drugs in plasma samples with satisfactory recoveries in the range of 95.0-97.5%.<br>• A stable isotope labeling strategy for analyzing thiol-containing drugs has been developed. • A pair of SIL reagents NCPM-d0 and NCPM-d2 were used to label thiol-containing drugs. • The detection sensitivities of thiol-containing drugs improved by 14.5-650.5-fold. • The proposed method was successfully applied to pharmacokinetic study of captopril.
Sample pretreatment is a critical and essential step in almost all analytical procedures, especially for the analysis of biological and environmental samples with complex matrices. Dopamine molecules can easily self-polymerize under weak alkaline conditions, leading to a facile deposition of polydopamine (PDA) coatings on various surfaces. Since 2011, PDA chemistry has undergone significant expansion in its applications and is becoming one of the most attractive areas within the materials field. Here, recent advancements in the use of PDA-derived adsorbents for sample pretreatment were reviewed, with especial focus on surface modification strategies, extraction modes, and application fields. In addition, prospects of PDA-derived adsorbents for sample pretreatment are also proposed.<br>• Analytical applications of PDA-derived adsorbents are insightfully reviewed. • PDA has been directly used as an adsorbent for building extraction methods. • PDA has also been used as versatile mediums for fabricating various adsorbents. • PDA has greatly promoted the diversity of extraction modes because of its adhesion.