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  • Author or Editor: Ling Zhang x
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You-Gui-Yin (YGY), a famous traditional Chinese medicine, has been widely used in clinics for the treatment of kidney-yang deficiency, yang deficiency caused by excessive yin, and osteoporosis. A rapid and sensitive ultraperformance liquid chromatography–electrospray ionization–mass spectrometry (UPLC–ESI–MS) method for simultaneous determination of six Aconitum alkaloids including aconitine (AC), hypaconitine (HA), mesaconitine (MA), benzoylaconine (BAC), benzoylhypaconine (BHA), and benzoylmesaconine (BMA) in rat plasma after oral administration of YGY was developed in this study. Chromatographic separation was performed on an ACQUITY UPLC™ BEH C18 column (2.1 × 100 mm, 1.7 μm) using gradient elution with the mobile phase consisting of 2 mmol/L ammonium formate in 0.05% formic acid aqueous solution and 0.05% formic acid methanol solution, at a flow rate of 0.20 mL/min. MS detection was performed in the positive ion mode. The calibration curves were linear in the concentration range of 0.04160–41.60 ng/mL, 0.1070–107.0 ng/mL, 0.07358–73.50 ng/mL, 0.03228–32.28 ng/mL, 0.01809–18.09 ng/mL, and 0.1320–132.0 ng/mL for AC, HA, MA, BAC, BHA, and BMA, respectively. The intra- and inter-day precisions (relative standard deviation [RSD]) were less than 11.6% and 12.6%, respectively. The accuracies Relative Error (RE) ranged from −10.2% to 5.6%, while the recoveries ranged from 70.4% to 99.3%. The method for simultaneous quantitation of Aconitum alkaloids of You-Gui-Yin in rat plasma is accurate and repeatable, and this method was successfully applied to investigate the pharmacokinetics of the six Aconitum alkaloids in rat plasma after oral administration of YGY. For the pharmacokinetic study, the pharmacokinetics of the six Aconitum alkaloids were best described by a two-compartment open model.

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An article assessment system based on both Tianjin University and nine key Chinese Universities’ academic disciplinary benchmarks was established to evaluate researcher’s published papers. With this scientific benchmarking system, the quality of a researcher’s papers could be easily located in a percentile scale in corresponding field within certain groups. Several factors, including total number of papers, order of authors, impact of journals, citation count, h-index, e-index, a-index, m-quotient, etc., were also utilized for both quantity and quality analysis. Furthermore, the novel proposed weighted citation analysis was introduced to judge a researcher’s contribution to his/her research outcomes. The convenient application and comprehensive evaluation property of this assessment system was thoroughly discussed via a given example.

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Authors: Ju-Lan Zeng, Sai-Bo Yu, Zhong Cao, Dao-Wu Yang, Li-Xian Sun, Ling Zhang and Xiong-Fei Zhang

Abstract

A new potential enantioselective catalyst derived from ferrocene, 1-{(R)-1-[(S)-2-(diphenylphosphino)ferrocenyl]ethyl}-benzimidazole (DPFEB), was prepared and its absolute structure was characterized by means of single crystal X-ray diffraction. The molar heat capacity of DPFEB was measured by means of temperature modulated differential scanning calorimetry over the temperature range of 200–530 K, and the thermodynamic functions of [H TH 298.15] and [S TS 298.15] were calculated. Further more, thermogravimetry experiment revealed that DPFEB exhibited a three step thermal decomposition process with the final residual of 28.7%.

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A convenient method was developed for simultaneous determination of 11 preservatives in cosmetics and pharmaceuticals. Matrix solid-phase dispersion had been optimized as the sample pretreatment technology, using Florisil as a dispersant, anhydrous sodium sulfate as a dehydrant, formic acid as an additive, and n-hexane and ethyl acetate as eluents successively, and followed by gas chromatography–flame ionization detection on a TR-5 capillary column. Experimental results showed that 11 preservatives were baseline separated within 22 min. Good linearities were observed in the concentration range of 0.53–250 μg/mL for all analytes, and there were also minor differences. All correlation coefficients (r) were more than 0.995. The average recoveries at 3 levels of spiked samples ranged from 80% to 124% with 0.9–12% intra-day RSD and 1.8–12% inter-day RSD. The limits of detection were less than 0.18 μg/mL for all analytes. Besides, there was no obvious matrix effect on the analytes. The conclusion was that the developed method was simple, cheap, accurate, precise, and environment-friendly, in addition to existing little matrix effects. It could be recommended to determine 11 preservatives individually or in any their combinations to not only in liquid and gel cosmetics but also in liquid medicine and ointment.

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Abstract

Thermotropic phase behaviors of paeonol-encapsulated liposomes containing stigmasterol or cholesterol have been investigated by differential scanning calorimetry. We compared the thermotropic phase behavior of pure dipalmitoylphosphatidylcholine (DPPC) liposomes, sterol/DPPC liposomes, and paeonol/sterol/DPPC liposomes increasing the ratio of paeonol to sterol from 0 to 1, by analyzing the calorimetric parameters of main phase transition of liposomes including phase transition temperature (onset temperature and peak temperature) and phase transition cooperativity. The results showed that paeonol could incorporate into the hydrophobic region of DPPC, thus, decrease phase transition temperature of DPPC. Though stigmasterol interacts with DPPC less favorably than cholesterol, thermotropic phase behavior of paeonol/cholesterol/DPPC liposomes and that of paeonol/stigmasterol/DPPC liposomes are very similar. A phase separation occurred when the molar ratio of paeonol to sterol reached 1:1 in paeonol-encapsulated liposomes, where a paeonol-rich domain coexisted with a sterol-rich domain. The packing order of acyl chains of DPPC in sterol-rich domain is a little higher than that in paeonol-rich domain.

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Splenic lymphocytes play an important role in host acute or chronic diseases. The abnormality of these cells in the spleens of humans might lead to some riskful diseases for human. Hence, in this study, the effects of two ginsenosides Rg1 and Rb1 on splenic lymphocytes growth were studied by microcalorimetry. Some qualitative and quantitative information, such as the metabolic power-time curves, growth rate constant k, maximum heat-output power of the exponential phase P max, total heat output Q t of splenic lymphocytes were obtained to present the effects of Rg1 and Rb1 on these cells. The values of k, P max, and Q t from the thermogenic growth curves of splenic lymphocytes were found to increase in the presence of Rg1, while the change was adverse for Rb1, illustrating that Rg1 had promotion effect and Rb1 had inhibitory effect on splenic lymphocytes growth and these promotion or inhibitory effects were enhanced with increasing the concentration of the two compounds, respectively. The microcalorimetric results were confirmed by MTT assay for determining the MTT optical density (OD) value and [3H] Thymidine incorporation assay ([3H]-TdR) for determining the count per minute (cpm) value: Rg1 could increase the MTT OD value and the cpm value of [3H]-TdR incorporation into splenic lymphocytes, and these values were increased with increasing the concentration of this compound, while Rb1 had the adverse results. The structure–activity relationships showed that the glucopyranoside and hydroxyl groups at the dammarane-type mother nucleus skeleton might play a crucial role for the opposing effects of the two ginsenosides on splenic lymphocytes. Compared with the other two assay methods, the microcalorimetric method provided more useful and reliable information for quickly and objectively evaluating the effects of drugs or compounds on the living cells, which would be a highly promising analytical tool for the characterization of the biological process and the estimation of the drugs’ efficiency.

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In this study, the activities of four ginsenosides Rc, Re, Rd, and Rf on splenic lymphocytes growth were studied by microcalorimetry. Some qualitative and quantitative information, such as the metabolic power–time curves, growth rate constant k, maximum heat-output power of the exponential phase P max and the corresponding appearance peak time t max, total heat output Q t, and promotion rate R p of splenic lymphocytes growth affected by the four ginsenosides were calculated. In accordance with thermo-kinetic model, the corresponding quantitative relationships of k, P max, t max, Q t, R p, and c were established. Also, the median effective concentration (EC50) was obtained by quantitative analysis. Based on both the quantitative quantity–activity relationships (QQAR) and EC50, the sequence of promotion activity was Rc > Re > Rd > Rf. The analysis of structure–activity relationships showed that the number, type, and position of sugar moieties on the gonane steroid nucleus had important influences on the promotion activity of Rc, Re, Rd, and Rf on splenic lymphocytes growth. Microcalorimetry can be used as a useful tool for determining the activity and studying the quantity–activity relationship of drugs on cell.

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Authors: Li-Fang Song, Chun-Hong Jiang, Jian Zhang, Li-Xian Sun, Fen Xu, Yun-Qi Tian, Wan-Sheng You, Zhong Cao, Ling Zhang and Dao-Wu Yang

Abstract  

A novel two-dimensional metal organic framework MgBTC [MgBTC(OCN)2·2H2O, where BTC = 1,3,5-benzenetricarboxylate] has been synthesized solvothermally and characterized by single crystal XRD, powder XRD, FT-IR spectra. The low-temperature molar heat capacities of MgBTC were measured by temperature modulated differential scanning calorimetry (TMDSC) over the temperature range from 190 to 350 K for the first time. No phase transition or thermal anomaly was observed in the experimental temperature range. The thermodynamic parameters of MgBTC such as entropy and enthalpy relative to reference temperature of 298.15 K were derived based on the above molar heat capacities data. Moreover, the thermal stability and decomposition of MgBTC was further investigated through thermogravimetry (TG)-mass spectrometer (MS). Four stages of mass loss were observed in the TG curve. TG-MS curve indicated that the products of oxidative degradation of MgBTC are H2O, N2, CO2 and CO. The powder XRD showed that the mixture after TG contains MgO and graphite.

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The compound 3-{[4-(4-[18F]fluorophenyl)methyl]piperazin-1-yl}-methyl-1H-pyrrolo[2,3-b]pyridine ([18F]3), which is an analogue of L-745,870 binding D4

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Chromosome segment substitution lines (CSSLs) are powerful tools to combine naturally occurring genetic variants with favorable alleles in the same genetic backgrounds of elite cultivars. An elite CSSL Z322-1-10 was identified from advanced backcrosses between a japonica cultivar Nipponbare and an elite indica restorer Xihui 18 by SSR marker-assisted selection (MAS). The Z322-1-10 line carries five substitution segments distributed on chromosomes 1, 2, 5, 6 and 10 with an average length of 4.80 Mb. Spikilets per panicle, 1000-grain weight, grain length in the Z322-1-10 line are significantly higher than those in Nipponbare. Quantitative trait loci (QTLs) were identified and mapped for nine agronomic traits in an F3 population derived from the cross between Nipponbare and Z322-1-10 using the restricted maximum likelihood (REML) method in the HPMIXED procedure of SAS. We detected 13 QTLs whose effect ranging from 2.45% to 44.17% in terms of phenotypic variance explained. Of the 13 loci detected, three are major QTL (qGL1, qGW5-1 and qRLW5-1) and they explain 34.68%, 44.17% and 33.05% of the phenotypic variance. The qGL1 locus controls grain length with a typical Mendelian dominance inheritance of 3:1 ratio for long grain to short grain. The already cloned QTL qGW5-1 is linked with a minor QTL for grain width qGW5-2 (13.01%) in the same substitution segment. Similarly, the previously reported qRLW5-1 is also linked with a minor QTL qRLW5-2. Not only the study is important for fine mapping and cloning of the gene qGL1, but also has a great potential for molecular breeding.

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