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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]

In this paper, an ultra-high-performance liquid chromatography coupled with linear ion trap quadrupole Orbitrap high resolution mass spectrometry (UHPLC-LTQ-Orbitrap HRMS) method was developed and validated for identification, confirmation and quantitation of illegal adulterated weight-loss drugs in plant dietary supplements. 13 wt-loss drugs were well separated by the gradient elution of 10 mmol/L ammonium acetate − 0.05% formic acid H 2 O and acetonitrile at a flow rate of 0.2 mL/min within 12 min. The MS analysis was operated under the positive ion and in full MS/dd-MS 2 (data-dependent MS 2 ) mode. The full MS scan with resolution at 60 000 FWHM and narrow mass windows at 5 ppm acquired data for identification and quantitation, and dd-MS 2 scan with resolution at 15 000 FWHM obtained product ions for confirmation. The method validation showed good linearity with coefficients of determination (r 2 ) higher than 0.9951 for all analytes. Meantime, all the LOD and LLOQ values were in the respective range of 0.3–2 and 1–9 ng/g. The accuracy, intra- and inter-day precision were in the ranges of −1.7 to 3.4%, 1.7–5.0% and 1.9–4.4%, respectively. The mean recoveries ranged from 85.4 to 107.1%, while the absolute and relative matrix effect were in the corresponding range of 98.2–108.6% and 2.6–8.7%. Among 120 batches of weight loss plant dietary supplements, sibutramine and fluoxertine or both were positive in 29 samples. In general, LTQ-Orbitrap HRMS technology was a powerful tool for the analysis of illegal ingredients in dietary supplements. [ABSTRACT FROM AUTHOR]

In this paper, we define a general analytical domain and two reflection coefficients to study the long-time asymptotics for a defocusing mixed nonlinear Schrödinger equation with the Schwartz initial data. It is shown that the solution of the initial value problem for the mixed Schrödinger equation can be expressed in terms of the solution associated with a Riemann-Hilbert problem. The long-time asymptotic of the mixed Schrödinger equation is further obtained via the Deift-Zhou nonlinear steepest descent method. The long-time asymptotic for the classical Schrödinger equation, derivative Schrödinger equation and modified Schrödinger equation are obtained directly from our results as special cases. [ABSTRACT FROM AUTHOR]

Abstract: In order to determine the contribution of intranasal (i.n.) administration to the uptake of large molecular weight (MW) substances into central nervous system (CNS), concentration in brain of the centrally acting polypeptide cobrotoxin (NT-I) versus time profiles were studied using dual-probe microdialysis in awake free-moving rats. NT-I, radiolabeled with sodium 125I-Iodide (125I-NT-I), was administered at the dose of 105μg/kg intravenously and intranasally in the same set of rat (n =15). The 125I-NT-Inasal preparations were formulated with borneol/menthol eutectic mixture (+BMEM) as an absorption enhancer and without (−BMEM). After application, the dialysates sampled simultaneously from olfactory bulb and cerebellar nuclei were measured in a gamma-counter for radioactivity. The real concentrations of NT-I were recalculated by in vivo recoveries of microdialysis probes. The results showed that the area under the curve (AUC) value in cerebellar nuclei (2283.51±34.54minng/ml) following i.n. administration (+BMEM) was significantly larger than those (AUColfactory =1141.92±26.42minng/ml; AUCcerebellar =1364.62±19.35minng/ml) after intravenous (i.v.) bolus, respectively. A prolonged time values to peak concentrations after i.n. application (+BMEM) were observed compared with those following i.v. administration. Also, following i.n. application (+BMEM) the measured time value to peak concentration in cerebellar nuclei (85min) was statistically longer than that in olfactory bulb (75min), which could be plausibly an indication for NT-I delivery into brain via nose–brain pathway in the presence of absorption enhancer. i.n. administration (−BMEM) had little or no ability of NT-I delivering into brain. In conclusion, i.n. administration (+BMEM) significantly enhanced brain transport of NT-I with uneven distribution in discrete regions of brain compared with i.v. administration. Additionally, multi-probe microdialysis technique should be considerably valuable in brain delivery studies. [Copyright &y& Elsevier]

The nanoscale Lycurgus cup arrays were hybrid structures of nanocups and nanoparticles with ultrasensitivity to refractive index change. In this study, an electrochemical localized surface plasmon resonance (LSPR) sensor was developed by coupling electrochemistry to LSPR spectroscopy measurement on the nanoscale cup arrays (nanoCA). Based on the combination of electrochemistry and LSPR measurement, the electrochemical LSPR on nanoCA was observed with significant resonance wavelength shifts in electrochemical modulation. The synchronous implementation of cyclic voltammetry and optical transmission spectrum can be used to obtain multiply sensing information and investigate the enhancement for LSPR from electrochemical scanning. The electrochemical enhanced LSPR was utilized as biosensor to detect biomolecules. The electrochemical LSPR biosensor with synchronous electrochemical and optical implement showed higher sensitivity than that of conventional optical LSPR measurement. Detecting with multi-transducer parameters and high sensitivity, the electrochemical LSPR provided a promising approach for chemical and biological detection. [ABSTRACT FROM AUTHOR]