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In this experiment, by determination of the HPLC characteristic spectrum of the classical prescription Qingwei San decoction, the contents of isoferulic acid, palmatine and paeonol in Qingwei San decoction and the extraction rate were investigated. The factors such as the crushing degree of decoction pieces, the amount of decocting water, the decocting time, the filter material and the decocting container involved in Qingwei San decoction process were examined to make a detailed comparison of Qingwei San's decoction processes during the development.HPLC characteristic spectrum method of Qingwei San was established, and then the decoction process parameters of Qingwei San were optimized, with the similarity of characteristic spectrum, the concentration of the index components and the extraction rate as indexes. The decoction process of Qingwei San was determined as follows: Qingwei San decoction pieces were weighed according to the prescription amount and pulverized into the most coarse powder; the powder was put in a ceramic pot, added with 225 mL water, heated to boiling, cooked for 50 minutes with gentle heat(100 W), and filtered with a layer of 300 mesh nylon cloth.The similarity of Qingwei San's characteristics pectrum of different decoction methods was all above 0.9, and the concentration of isoferulic acid, palmatine and paeonol in Qingwei San under determined decoction process was 40.74, 26.73, 65.73 μg·mL~(-1), respectively, with an extraction rate of 33.80%.The characteristic spectrum determined in this experiment can better express the information and index components of Qingwei San, and if combined with the extraction rate information, it can provide the general information, index component content and extraction information. The decoction process after detailed investigation can better reflect the quality of Qingwei San decoction, with easier control and operation. It can provide a basis for the subsequent research and development of Qingwei San decoction standard, and can also provide experimental basis and reference for the decoction process research of other classical prescriptions.

We present three new hybrid layered lead(II) bromide perovskites of generic composition A 2 PbBr 4 or AA'PbBr 4 that exhibit three distinct structure types. [TzH] 2 PbBr 4 ([TzH + ] = 1,2,4-triazolium) adopts a (001)-oriented layer structure and [AaH] 2 PbBr 4 , ([AaH + ] = acetamidinium) adopts a (110)-oriented type, whereas [ImH][TzH]PbBr 4 , ([ImH + ] = imidazolium) adopts a rare (110)-oriented structure with enhanced corrugation (i.e., 3 × 3 type). The crystal structures of each are discussed in terms of the differing nature of the templating molecular species. Photoluminescent spectra for each are reported and the behaviors discussed in relation to the different structure of each composition.

It has been shown that cell volume regulation mechanisms play important roles in various cell functions. We demonstrated previously that volume-activated chloride channels were involved in cell volume regulation. The present study aimed to clarify the roles of various types of potassium channels in regulatory volume decrease (RVD) induced by hypotonic challenges in human nasopharyngeal carcinoma cells (CNE-2Z cells). The whole-cell patch clamp technique was used to record hypotonic challenge-induced potassium currents. During current recordings, cells were held at 0 mV and stepped to +/-46 and +/-92 mV, repeatedly. The cell volume was computed from cell diameters. The changes of cell volume were monitored and analyzed by the time-lapse imaging technique. The results showed that the exposure to 160 mOsm/L hypotonic solution caused the cells to swell by (144.5+/-4.2)%, activated a potassium current (59.2 pA/pF+/-13.3 pA/pF at 92 mV), and induced RVD. Cell volume was recovered from hypotonic challenge-induced swelling by (48.9+/-4.6)% after 20 min. The potassium current (at 92 mV) and RVD were inhibited by the calcium-dependent potassium channel blocker, clotrimazole (100 mumol/L), by (98.5+/-2.8)% and (89.3+/-4.9)%, respectively. Depletion of extracellular calcium prevented the activation of the hypotonic challenge-induced potassium current and inhibited the process of RVD. The voltage-gated potassium channel blocker, 4-AP (5 mmol/L), partially inhibited the hypotonic challenge-activated potassium currents by (66.6+/-5.3)% (at 92 mV). These results suggest that the Ca(2+)-dependent potassium channel is the main component of volume-activated potassium channels and plays an important role in volume regulation of CNE-2Z cells. The voltage-gated potassium channels may also contribute in part to the formation of the volume-activated potassium current.