UiO-66/PIM-1 Mixed-Matrix Membrane for Hexane Isomer Separation.

The separation of high-octane dibranched alkanes from naphtha is critical in the refining of gasoline. To date, research on the membrane-based separation of alkane isomers has been limited, with a particular paucity of investigations into mixed-matrix membranes. Herein, the continuous and dense UiO-66/PIM-1 mixed-matrix membrane, which was prepared through precise control of the interfacial structure, was first applied to the differentiation of C6 alkane isomers. Due to the synergistic combination of UiO-66 with differential adsorption capabilities for alkanes and PIM-1 that possesses a cross-linkable structure, the resulting UiO-66/PIM-1-(20) membrane demonstrated remarkable separation performance and high stability. Pervaporation measurements showed that the mass fraction of 2,2-dimethylbutane in the feed side was increased from 50.0 to 75.8 wt % while an excellent flux of 1700 g m-2 h-1 was maintained over a continuous 40 h period. The UiO-66/PIM-1-(20) membrane, characterized by its facile replication and processing, shows potential for large-scale fabrication. This study offers a new approach to the membrane separation of alkane isomers.

Simultaneous determination of thirteen aminoalcohol-diterpenoid alkaloids in the lateral roots of Aconitum carmichaeli by solid-phase extraction-liquid chromatography-tandem mass spectrometry.

Aminoalcohol-diterpenoid alkaloids have been reported as the cardioactive components in the lateral roots of Aconitum carmichaeli (Fuzi) according to recent studies. Determination of these effective components is of great significance for quality control purposes for Fuzi. Here we report, for the first, the development and validation of a new method to determine the 13 aminoalcohol-diterpenoid alkaloids in Fuzi by using a simple and accurate solid-phase extraction-liquid chromatography-tandem mass spectrometry. The chromatographic analysis was performed on an ODS column with methanol-0.1 % formic acid (80 : 20, v/v) as the mobile phase. The quantification was performed using MS/MS detection in the positive ion mode with multiple reaction monitoring. Linearity was observed within a range of concentrations of 20-2,000 ng/mL. For all the analytes, the r value was greater than 0.9990. The limit of detection and the limit of quantitation were less than 0.5 ng/mL and 2.0 ng/mL, respectively. The intraday and interday precisions were less than 5% and 10%, respectively. The accuracy was within the range of 90 to 105%. This method was successfully applied to determine the 13 aminoalcohol-diterpenoid alkaloids in Fuzi from different origins and with different processing methods.

[Identification of aminoalcohol-diterpenoid alkaloids in Aconiti Lateralis Radix Praeparata and study of their cardiac effects].

In order to affirm the cardioactive components in Fuzi, we identified a group of aminoalcohol- diterpenoid alkaloids in Fuzi using ultra high-performance liquid chromatography coupled with electrospray ionization mass spectrometer (UPLC-ESI-MS) method. Among a total of forty-one isolated ingredients, thirteen major aminoalcohol-diterpenoid alkaloids were identified by comparing their retention times and MS spectra with those of the reference substances. Moreover, Fuzi samples from different places of origin and with different processing methods were examined and their components displayed a pattern of high similarity, though the relative abundance varies probably due to their different processing methods. Furthermore, the cardiac effect of each identified alkaloid was individually evaluated using the isolated bullfrog heart perfusion experiment. Among the thirteen aminoalcohol diterpenoid alkaloids tested, six of them significantly enhanced the amplitude rates. Taken together, we affirm that the cardioactive components in Fuzi are aminoalcohol-diterpenoid alkaloids, shedding light on future studies of the mechanisms and development of these cardioactive compounds.

Activation of the MEK/ERK Pathway Mediates the Inhibitory Effects of Silvestrol on Nasopharyngeal Carcinoma Cells via RAP1A, HK2, and GADD45A.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a malignant tumor associated with Epstein-Barr virus (EBV) infection. Chemoradiotherapy is the mainstream treatment for locally advanced NPC, and chemotherapeutic drugs are an indispensable part of NPC treatment. However, the toxic side-effects of chemotherapy drugs limit their therapeutic value, and new chemotherapy drugs are urgently needed for NPC. Silvestrol, an emerging natural plant anticancer molecule, has shown promising antitumor activity in breast cancer, melanoma, liver cancer, and other tumor types by promoting apoptosis in cancer cells to a greater extent than in normal cells. However, the effects of silvestrol on NPC and its possible molecular mechanisms have yet to be fully explored. METHODS: Cell counting kit-8 (CCK-8), cell scratch, flow cytometry, 5-ethynyl-2'-deoxyuridine (EdU), and Western blot (WB) assays were used to evaluate the effects of silvestrol on the cell viability, cell cycle, apoptosis, and migration of NPC cells. RNA sequencing (RNA-Seq) was used to study the effect of extracellular signal-regulated kinase (ERK) inhibitors on the cell transcriptome, and immunohistochemistry (IHC) to assess protein expression levels in patient specimens. RESULTS: Silvestrol inhibited cell migration and DNA replication of NPC cells, while promoting the expression of cleaved caspase-3, apoptosis, and cell cycle arrest. Furthermore, silvestrol altered the level of ERK phosphorylation. The ERK-targeted inhibitor LY3214996 attenuated silvestrol-mediated inhibition of NPC cell proliferation but not migration. Analysis of RNA-Seq data and WB were used to identify and validate the downstream regulatory targets of silvestrol. Expression of GADD45A, RAP1A, and hexokinase-II (HK2) proteins was inhibited by silvestrol and LY3214996. Finally, IHC revealed that GADD45A, RAP1A, and HK2 protein expression was more abundant in cancer tissues than in non-tumor tissues. CONCLUSIONS: Silvestrol inhibits the proliferation of NPC cells by targeting ERK phosphorylation. However, the inhibition of NPC cell migration by silvestrol was independent of the Raf-MEK-ERK pathway. RAP1A, HK2, and GADD45A may be potential targets for the action of silvestrol.

Effects of the New Lift-Thrust Operation in Laser Acupuncture Investigated by Thermal Imaging.

Acupuncture manipulation is one of the key factors affecting the performance of acupuncture in Traditional Chinese Medicine. Lift-thrust and twirl-twist are two of the most commonly used manipulation methods for needle acupuncture. We previously have developed a novel laser acupuncture model that emulates lift-thrust operation. In this study, we intend to show the effectiveness of such a model by applying it on the Neiguan acupoint (PC6). Stimulation was reported to be beneficial for improving cardiac output and peripheral circulation. Therefore, we hypothesized that the stimulation of laser acupuncture may increase the temperature of the subjects' fingertip due to increased peripheral blood flow. A thermal imager was used to measure the temperature change of subjects' fingertips. Through regression analysis, it has been shown that while PC6 is stimulated, laser acupuncture with lift-thrust operation caused a more rapid, stable, and lasting temperature rise of fingertip than that without lift-thrust operation. On the contrary, we observe no significant temperature change when a sham point nearby PC6 (a point which is not traditionally defined as the acupoint) was stimulated. Our results suggest the emulation of manipulation methods such as the lift-thrust operation could be a potential direction for the future development of laser acupuncture.

Further Studies on Structure-Cardiac Activity Relationships of Diterpenoid Alkaloids.

The cardiac effect of thirty-eight diterpenoid alkaloids was evaluated on the isolated bullfrog heart model. Among them, twelve compounds exhibited appreciable cardiac activity, with compounds 3 and 35 being more active than the reference drug lanatoside. The structure-cardiac activity relationships of the diterpenoid alkaloids were summarized based on our present and previous studies [2]: i) 1α-OMe or 1α-OH, 8-OH, 14-OH, and NH (or NMe) are key structural features important for the cardiac effect of the aconitine-type C19-diterpenoid alkaloids without any esters. C18-diterpenoid alkaloids, lycoctonine-type C19-diterpenoid alkaloids, and the veatchine- and denudatine-type C20-diterpenoid alkaloids did not show any cardiac activity; ii) the presence of 3α-OH is beneficial to the cardiac activity; iii) the effect on the cardiac action of 6α-OMe, 13-OH, 15α-OH, and 16-demethoxy or a double bond between C-15 and C-16 depends on the substituent pattern on the nitrogen atom.