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Currently, illegal addition of anti-infective drugs has been detected in some cosmetics to achieve rapid sterilization and anti-inflammatory effects. However, the abuse of anti-infective drugs may endanger the health of citizens. Thus, methods for the detection and quantitative determinations of such substances should be developed. In this paper, a method combining ultra-high-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF HRMS) was designed. Its significance and potential were verified by the identification, confirmation, and quantification of 37 illegally added anti-infective drugs in cosmetics that claimed to have anti-acne effects. The method validation revealed a satisfactory linear relationship, and each coefficient of determination (r2) was higher than 0.9943. The LOD and LLOQ results were in the ranges of 0.0003–0.1063 μg g−1 and 0.0012–0.3545 μg g−1, respectively. The accuracy ranged from 70.8 to 122.8%, whereas the intra- and inter-day precisions were in the ranges of 0.2–12.8% and 0.2–13.8%, correspondingly. The mean recoveries were in the range of 70.1–117.7%, and the matrix effects ranged from 73.0 to 121.4%. Of the 200 batches of cosmetics that claimed to have anti-acne effects, three batches were positive, with chemical components such as metronidazole, lincomycin, clindamycin, tinidazole and miconazole nitrate being discovered. Therefore, the Q-TOF spectrometry could be widely applied in routine screening of adulteration in cosmetics. [ABSTRACT FROM AUTHOR]

In this paper, we consider the initial value problem for the mixed Schrödinger equation. For the Schwartz initial data q 0 (x) ∈ S (R) , by defining a general analytical domain and two reflection coefficients, we ever found an unified long-time asymptotic formula via the Deift–Zhou nonlinear steepest descent method. In this paper, under essentially minimal regularity assumptions on initial data in a much weak weighted Sobolev space q 0 (x) ∈ H 2 , 2 (R) , we apply the ∂ ̄ steepest descent method to obtain long-time asymptotics for the mixed Schrödinger equation. In the asymptotic expression, the leading order term O ( t − 1 / 2 ) comes from the dispersive part qt + iqxx and the error order O ( t − 3 / 4 ) comes from a ∂ ̄ equation. [ABSTRACT FROM AUTHOR]

Background: The blood-brain barrier (BBB) is the greatest challenge in the treatment of intracranial malignant tumors. Objective: The aim of this study is to determine the role of borneol in opening the BBB and elucidate the underlying mechanisms. Materials and Methods: Twenty Sprague-Dawley (SD) rats were randomized into borneol group intragastrically administered with 10% borneol corn oil (2 mL/kg) and control group. After 30 minutes, 2% Evans blue (4 mL/kg) was injected. Thirty minutes later, brain tissue was analyzed using the Evans blue standard curve. Another 40 SD rats were randomized into high-, medium-, and low-dose borneol groups and a control group. Each rat in the experimental groups was intragastrically administered with 10% borneol corn oil (2 mL/kg, 1.25 mL/kg, and 0.5 mL/kg, respectively). The control group was injected with corn oil of 1.25 mL/kg. After 30 minutes, the rats were killed, and the brain tissues were collected. The expression of occludin, occludens-1, nitric oxide synthase, P-glycoprotein, and intercellular cell adhesion molecule-1 (ICAM-1) was detected by immunohistochemy. Results: The concentration of Evans blue in the borneol group was higher than in the control group (P < .05). The mean density of ICAM-1 expression was higher in the experimental group than in the control group (P < .05). In contrast, significant differences of positive area and total density of ICAM-1 were shown only between the high-dose group and the control group (P < .05). Conclusion: Borneol can open the BBB, which might be related with the increased expression of ICAM-1. [ABSTRACT FROM AUTHOR]