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Guojin Ren,1,* Qili Zhang,1,2,* Pengfei Xia,1– 4 Jie Wang,1 Pengxia Fang,1 Xiaojie Jin,1 Xuejing Peng,1– 4 Yanli Xu,1,5 Jian Zhang,1– 4 Lei Zhao1– 5 1Gansu University of Chinese Medicine, Lanzhou, 730000, People’s Republic of China; 2Northwest Collaborative Innovation Center for Traditional Chinese Medicine Co-Constructed by Gansu Province & MOE of PRC, Lanzhou, 730000, People’s Republic of China; 3Key Laboratory of Chemistry and Quality of TCM of the College of Gansu Province, Lanzhou, 730000, People’s Republic of China; 4Gansu Province Engineering Laboratory for TCM Standardization Technology and Popularization, Lanzhou, 730000, People’s Republic of China; 5Lanzhou Institute for Food and Drug Control, Lanzhou, 730000, People’s Republic of China*These authors contributed equally to this workCorrespondence: Lei Zhao; Jian Zhang, Email zzyhx@gszy.edu.cn; zhangjian@gszy.edu.cnPurpose: Nonsteroidal anti-inflammatory drugs cause a series of adverse reactions. Thus, the search for new cyclooxygenase-2 selective inhibitors have become the main direction of research on anti-inflammatory drugs. Gentiopicroside is a novel selective inhibitor of cyclooxygenase-2 from Chinese herbal medicine. However, it is highly hydrophilic owing to the presence of the sugar fragment in its structure that reduces its oral bioavailability and limits efficacy. This study aimed to design and synthesize novel cyclooxygenase-2 inhibitors by modifying gentiopicroside structure and reducing its polarity.Materials and Methods: We introduced hydrophobic acyl chloride into the gentiopicroside structure to reduce its hydrophilicity and obtained some new derivatives. Their in vitro anti-inflammatory activities were evaluated against NO, TNF-α, PGE2, and IL-6 production in the mouse macrophage cell line RAW264.7 stimulated by lipopolysaccharide. The in vivo inhibitory activities were further tested against xylene-induced mouse ear swelling. Molecular docking predicted that whether new compounds could effectively bind to target protein cyclooxygenase-2. The inhibitory activity of new compounds to cyclooxygenase-2 enzyme were verified by the in vitro experiment.Results: A total of 21 novel derivatives were synthesized, and exhibit lower polarities than the gentiopicroside. Most compounds have good in vitro anti-inflammatory activity. The in vivo activity results demonstrated that 8 compounds were more active than gentiopicroside. The inhibition rate of some compounds was higher than celecoxib. Molecular docking predicted that 6 compounds could bind to cyclooxygenase-2 and had high docking scores in accordance with their potency of the anti-inflammatory activity. The confirmatory experiment proved that these 6 compounds had significant inhibitory effect against cyclooxygenase-2 enzyme. Structure-activity relationship analysis presumed that the para-substitution with the electron-withdrawing groups may benefit the anti-inflammatory activity.Conclusion: These gentiopicroside derivatives especially PL-2, PL-7 and PL-8 may represent a novel class of cyclooxygenase-2 inhibitors and could thus be developed as new anti-inflammatory agents.Keywords: gentiopicroside derivatives, structural modification, anti-inflammatory, cyclooxygenase-2 inhibitors, molecular docking

Ca9MgLi(PO4)7: 4%Tb3+, 4%R+ (R = Li, Na, K) phosphors were synthesized by a solid-state reaction method. The crystal structure, morphology, composition and luminescent properties of as-prepared samples were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), energy dispersive spectrometer (EDS), high-angle annular dark field (HAADF) and spectroscopy technique. The effect of a small concentration of charge compensators like Li+, Na+, K+ on Ca9MgLi(PO4)7: Tb3+ phosphor has also investigated. Ca9MgLi(PO4)7: Tb3+, R+ (R = Li, Na, K) exhibit superior blue-green luminescence around 5D4 → 7F5 (543 nm) to Ca9MgLi(PO4)7: Tb3+ and can be effectively excited by 370 nm light, which implies that efficient charge compensation can promote the emitting of Tb3+ in Ca9MgLi(PO4)7. The CIE coordinates and decay lifetimes of typical samples were also studied. The Ca9MgLi(PO4)7: Tb3+, R+ (R = Li, Na, K) have promising application as a blue-green phosphor for near-ultraviolet chip excited white LEDs.

A series of CaSr(WO4)2: Eu3+ and CaSr(WO4)2: Eu3+, Li+ phosphors with different Eu3+ or Eu3+/Li+ molar contents were successfully synthesized by high-temperature solid-state reaction. Through a series of characterization methods, the composition, structure and luminescence characteristics of the sample are obtained. Upon excitation at 393 nm, the strong red light corresponding to the 5D0 → 7F2 transition of Eu3+ can be observed. The effect of Li+ charge compensation on the photoluminescence of the sample is studied. The strongest red emission is obtained through 1% Eu3+ and 1% Li+ doping. All of the results indicate that Li+ charge compensation can effectively enhance the red emissions intensity of Eu3+-doped CaSr(WO4)2 phosphors.

This paper presents an interferometer based on a single-mode fiber-multimode fiber-thin-core fiber (SMF–MMF–TCF) Michelson interference structure that can be used for the measurements of coolant level and refractive index. Because of the different diameters of the cores of the individual fibers, optical excitation and coupling occur at the splicing points of the fibers. The multimode fibers are the couplers in the sensing structure, which allow the exciting light to enter the cladding of the thin-core fibers. The end face of the thin-core fiber is coated with a silver film to enhance the reflectivity of the light. The results show that the interference intensity first increases and then decreases with the length of TCF. When TCF is 4 cm, the interference light intensity is the strongest. The sensitivity of the sensor is 138.091 nm/RIU with the linearity of 0.977 over the refractive index of the coolant in the range of 1.3605–1.3880, and the temperature and time effects on the sensor are small. The proposed sensor has the advantages of simple fabrication, high repeatability, and good stability and it can be applied to the measurements of coolant level and refractive index in automotive engines.

Cerebral ischemic stroke is one of the leading causes of morbidity and mortality worldwide, and rapidly increasing annually with no more effective therapeutic measures. Thus, the novel diagnostic and prognostic biomarkers are urgent to be identified for prevention and therapy of ischemic stroke. Recently, long noncoding RNAs (lncRNAs), a major family of noncoding RNAs with more than 200 nucleotides, have been considered as new targets for modulating pathological process of ischemic stroke. In this review, we summarized that the lncRNA-maternally expressed gene 3 (MEG3) played a critical role in promotion of neuronal cell death and inhibition of angiogenesis in response to hypoxia or ischemia condition, and further described the challenge of overcrossing blood-brain barrier (BBB) and determination of optimal carrier for delivering lncRNA' drugs into the specific brain regions. In brief, MEG3 will be a potential diagnostic biomarker and drug target in treatment and therapy of ischemic stroke in the future.

Vine tea has been used as an herbal tea by several ethnic minorities for hundreds of years in China. Flavonoids, a kind of indispensable component in a variety of nutraceutical, pharmaceutical and cosmetic applications, are identified to be the major metabolites and bioactive ingredients in vine tea. Interestingly, vine tea exhibits a wide range of significant bioactivities including anti-oxidant, anti-inflammatory, anti-tumor, antidiabetic, neuroprotective and other activities, but no toxicity. These bioactivities, to some extent, enrich the understanding about the role of vine tea in disease prevention and therapy. The health benefits of vine tea, particularly dihydromyricetin and myricetin, are widely investigated. However, there is currently no comprehensive review available on vine tea. Therefore, this report summarizes the most recent studies investigating bioactive constituents, pharmacological effects and possible mechanisms of vine tea, which will provide a better understanding about the health benefits and preclinical assessment of novel application of vine tea., Graphical abstract Image 1, Highlights • Vine tea has been consumed as a folk herbal tea for hundreds of years. • Flavonoids were the major bioactive ingredients in vine tea. • Dihydromyricetin and myricetin are major bioactives in vine tea. • Vine tea exhibits a wide range of significant bioactivities. • Vine tea may be a potential, functional herbal tea.

Pyridoxal 5'-phosphate (PLP) is the coenzyme of more than 140 enzymes and is widely used in various fields. In this study, to enhance the production of PLP in Escherichia coli BL21, the recombinant strain E. coli BL21/pETDuet-1-pdxj-zwf-dxs was constructed. The concentration of PLP in this strain was 82.69 mg/L, which was increased by 1.38-fold as compared to that in E. coli BL21. Glucose, yeast extract, and pH had an obvious impact on the concentration of PLP, and their optimal levels were 34.89 g/L, 31.17 g/L, and 10.07, respectively. The concentration of PLP under the optimal condition reached 2.23 g/L. The time-course analysis showed that the highest concentration of PLP was 2.32 g/L in recombinant strain after the induction for 12 h by 0.1 mM IPTG in a 1 L shake flask, which was increased by 38.76-fold as compared to that in E. coli BL21. This study provides a good basis for the efficient production of PLP in E. coli BL21.

The chaperone-assisted soluble expression and characterization of high molecular weight chitinase chiZJ408 in Escherichia coli BL21 were investigated. Chitin degradation products by chitinase chiZJ408 were analyzed. The results indicated that the introduction of the chaperone GroELS promoted the correct folding of chitinase chiZJ408 and increased its soluble expression by 14.9% (p < 0.05) in E. coli BL21. The optimal pH and temperature of chitinase chiZJ408 were respectively 6.0 and 50 °C. Chitinase chiZJ408 was stable at pHs of 4.0 ∼ 7.0 and at below 40 °C. Mg2+and Ca2+ had a significant impact on improving the activity of chitinase chiZJ408. Chitinase chiZJ408 was demonstrated to be exochitinase that cleaved the β-1,4-glycosidic bond of the chitin chain to generate only N,N'-diacetylchitobiose. This study broadens our understanding of chitinase and provides a basis for solving the problem of inclusion body formed by long fragment gene expression in E. coli.

The distribution network connects with families, more branch circuit breakers, more and more users rely on power in winter, which requires higher and higher reliability requirements for power supply. The power supply department is facing greater pressure to stop distribution line for de-icing. In view of the above reasons, this paper first briefly introduces several measures of de-icing without power failure, and selects the technical route of injecting reactive power at the end of the line for online de-icing; secondly, it introduces the principle of SVG device generating reactive power, which uses reactive power to generate heat loss in the distribution network line for on-line de-icing, and then proposes an improved reactive power outer loop control strategy to make it equivalent to current source De-icing device; Finally, a simulation model is built in PSCAD. Taking a 5km ACSR (LGJ-120) line with 5.4Mvar reactive power injected at the end of the line as an example, it can be seen that the line current reaches more than 500A due to the injected reactive power. The simulation results prove the effectiveness of the method. Considering its economy, it provides a feasible way for the distribution network with important loads Electric deicing scheme.

The in-depth investigation of hydrogen behaviors in Pu-oxide overlayers (mainly PuO2 and α-Pu2O3) is critical for modeling the complex induction period of Pu hydriding. Within density functional theory (DFT) + U + D3 schemes, our systematic first-principles calculations and ab initio thermodynamic evaluations reveal that the hydrogen incorporation, dissolution behaviors, and diffusion mechanism in PuO2 are quite different from those in α-Pu2O3, among which the highly endothermic incorporation and dissolution of hydrogen are the primary hydrogen resistance mechanism of PuO2. Since its difficult recombination, atomic H is the preferred existence state in PuO2, but H will recombine spontaneously in α-Pu2O3. In PuO2, H diffusion is always clinging to O anions, whereas in α-Pu2O3, H2 prefers to migrate along O vacancies with higher barriers. H dissolution in intact PuO2 is very difficult, which can only be driven by extremely high pressure PH2 and temperature. Based on a series of theoretical studies, we conclude that the main interactions between hydrogen and Pu-oxide overlayers are not involved with chemical reactions, and intact PuO2 can effectively inhibit hydrogen permeation.

Alzheimer’s disease (AD) is the leading cause of dementia throughout the world. It is characterized by major amyloid plaques and neurofibrillary tangles (NFTs), which are composed of amyloid-β (Aβ) peptide and hyperphosphorylated Tau (p-Tau), respectively. Exosomes, which are secreted by cells, are single-membrane lipid bilayer vesicles found in bodily fluids and they have a diameter of 30–150 nm. Recently, they have been considered as critical carriers and biomarkers in AD, as they facilitate communication between cells and tissues by delivering proteins, lipids, and nucleic acids. This review demonstrates that exosomes are natural nanocontainers that carry APP as well as Tau cleavage products secreted by neuronal cells and that their formation is associated with the endosomal–lysosomal pathway. Moreover, these exosomes can transfer AD pathological molecules and participate in the pathophysiological process of AD; therefore, they have potential diagnostic and therapeutic value for AD and might also provide novel insights for screening and prevention of the disease.

Pyridoxal 5'-phosphate (PLP) is the coenzyme of more than 140 enzymes and is widely used in various fields. In this study, to enhance the production of PLP in

ABI5-BINDING PROTEIN2 (AFP2) negatively regulates the abscisic acid signal by accelerating ABI5 degradation during seed germination in Arabidopsis (Arabidopsis thaliana). The abscisic acid signal is reported to delay flowering by up-regulating Flowering Locus C expression, but the role of AFP2 in regulating flowering time is unknown. Here, we found that flowering time was markedly delayed and CONSTANS (CO) expression was reduced in a transgenic Arabidopsis line overexpressing AFP2 under LD conditions. Conversely, the loss-of-function afp2 mutant showed slightly earlier flowering, with higher CO expression. These data suggest that AFP2 negatively regulates photoperiod-dependent flowering time by modulating the CO signal. We then found that AFP2 exhibited circadian expression rhythms that peaked during the night. Furthermore, the C-terminus of AFP2 interacted with CO, while its N-terminal ethylene response factor–associated amphiphilic repression motif interacted with the transcriptional corepressor TOPLESS-related protein2 (TPR2). Thus, AFP2 bridges CO and TPR2 to form the CO-AFP2-TPR2 complex. Biochemical and genetic analyses showed that AFP2 mediated CO degradation during the night. AFP2 also recruited histone deacetylase activity at Flowering Locus T chromatin through its interaction with TPR2. Taken together, our results reveal an elaborate mechanism by which AFP2 modulates flowering time through coordinating the activity and stability of CO.

We provide a principal Hugoniot of cryogenic liquid deuterium at a pressure of $27lPl240$ GPa, with reflected-shock data of up to $\ensuremath{\sim}830$ GPa. The maximum density reaches $\ensuremath{\sim}1.49$ $\mathrm{g}/{\mathrm{cm}}^{3}$, about 8.7 times the initial density. Our independent principal Hugoniot experimental data broadly support the wide-regime equation of state (WEOS) model, which well matches Fernandez-Pa\~nella et al. [Phys. Rev. Lett. 122, 255702 (2019)] and Knudson et al. [Phys. Rev. Lett. 118, 035501 (2017)] experimental data over the observed pressure range up to 550 GPa, and most of three sets of reflected shock data are in accordance with our theory up to 1 TPa. Our high-precision experimental results establish an important benchmark equation of state of deuterium and conform to the WEOS model quite well. Our work is useful for the development of the high-pressure response of hydrogen's isotopes, directly related to inertial confinement fusion, planetary science, and metallization.

The compound γ-aminobutyric acid (GABA) was widely used in various fields. To enhance the production of GABA in Escherichia coli BL21(DE3), the enzymes of the regeneration pathway of the coenzyme factor pyridoxal 5’-phosphate (PLP) were engineered. The recombinant E. coli strain was screened and identified. The initial concentrations of L-monosodium glutamate (L-MSG) had an obvious influence on the production of GABA. The highest concentration of GABA in recombinant E. coli BL21/pET28a-gadA was 5.54 g/L when the initial L-MSG concentration was 10 g/L, whereas it was 8.45 g/L in recombinant E. coli BL21/pET28a-gadA-SNO1-SNZ1 at an initial L-MSG concentration of 15 g/L. The corresponding conversion yields of GABA in these two strains were 91.0% and 92.7%, respectively. When the initial concentrations of L-MSG were more than 15 g/L, the concentrations of GABA in E. coli BL21/pET28a-gadA-SNO1-SNZ1 were significantly higher as compared to those in recombinant E. coli BL21/pET28a-gadA, and it reached a maximum of 13.20 g/L at an initial L-MSG concentration of 25 g/L, demonstrating that the introduction of the enzymes of the regeneration pathway of PLP favored to enhance the production of GABA. This study provides new insight into producing GABA effectively in E. coli BL21(DE3).

In this work, gold nanoparticles were biosynthesized via Plectranthus amboinicus leaf extract as the reducing agent. A series of techniques were used for sample analysis. The biosynthesized gold nanoparticles (bAuNPs) are a uniform size with a spherical shape. The FTIR analysis reveals the presence of many oxygen-containing functional groups on the bAuNP surface. The cyclic voltammetry and electrochemical impedance spectroscopic characterizations reveal that while the bAuNPs have a slightly lower conductivity than chemically synthesized AuNPs (cAuNPs). However, the bAuNPs have a superior electrocatalytic performance toward nicotine reduction. After optimization, the bAuNP-modified SPE could detect nicotine linearly from 10 to 2,000 μM with a low detection limit of 2.33 μM. In addition, the bAuNPs/SPE have been successfully used for nicotine-containing-product analysis.

The sound velocities of water in the Hugoniot states are investigated by laser shock compression of precompressed water in a diamond anvil cell. The obtained sound velocities in the off-Hugoniot region of liquid water at precompressed conditions are used to test the predictions of quantum molecular dynamics (QMD) simulations and the SESAME equation-of-state (EOS) library. It is found that the prediction of QMD simulations agrees with the experimental data while the prediction of SESAME EOS library underestimates the sound velocities probably due to its improper accounting for the ionization processes.

Seed germination is a vital developmental process that is tightly controlled by environmental signals, ensuring germination under favorable conditions. High temperature (HT) suppresses seed germination. This process, known as thermoinhibition, is achieved by activating abscisic acid and inhibiting gibberellic acid biosynthesis. The zinc-finger protein SOMNUS (SOM) participates in thermoinhibition of seed germination by altering gibberellic acid/abscisic acid metabolism, but the underlying regulatory mechanism is poorly understood. In this study, we report that SOM binds to its own promoter and activates its own expression in Arabidopsis (Arabidopsis thaliana) and identify the MADS-box transcription factor AGAMOUS-LIKE67 (AGL67) as a critical player in SOM function, based on its ability to recognize CArG-boxes within the SOM promoter and mediate the trans-activation of SOM under HTs. In addition, AGL67 recruits the histone mark reader EARLY BOLTING IN SHORT DAY (EBS), which recognizes H3K4me3 at SOM chromatin. In response to HTs, AGL67 and EBS are highly enriched around the SOM promoter. The AGL67-EBS complex is also necessary for histone H4K5 acetylation, which activates SOM expression, ultimately inhibiting seed germination. Taken together, our results reveal an essential mechanism in which AGL67 cooperates with the histone mark reader EBS, which bridges the process of H3K4me3 recognition with H4K5 acetylation, thereby epigenetically activating SOM expression to suppress seed germination under HT stress.

s 2-(2-Hydroxypropanamido) benzoic acid (HPABA) is a potential anti-inflammatory agent isolated from the marine fungus Penicillium chrysogenum . In vivo tissue distribution and excretion of HPABA were unknown. Therefore, the purpose of this paper was to establish an UHPLC–MS/MS method for the determination of HPABA and proceed to apply for the study of tissue distribution and excretion in rats. The results obtained indicated that HPABA in tissues was rapidly distributed and cleared. The highest level was found in intestine and stomach, followed by kidney, liver, lung and heart. These observations showed that HPABA was well distributed into abundant blood-supply tissues, suggesting that the blood flow or perfusion rate of organs plays a major role. A small amount of HPABA was detected in brain indicated that the ability of it in crossing the blood brain barrier (BBB) was very weak in rats. Excretion studies demonstrated that HPABA was mainly excreted by kidney. The total cumulative excretion of HPABA were 54.3% and 44.1% in male and female rats, respectively. In addition, gender-related differences in the excretion and distribution profile of HPABA were observed in rats.

Unravelling the surface physical and chemical properties, especially the surface activity of Pu-oxides (PuO2, α-Pu2O3) toward molecules, is essential to the long-term storage and surface reaction of Pu. Within DFT+U-D3 scheme, we systematically investigate the adsorption behaviors of H2O and CO2 on α-Pu2O3(111) surface, and clarify the different chemical activity of α-Pu2O3(111) surface from PuO2(111), which is due to the distinct coordination and bonding property of the top-layer Pu. There are five- and six-coordinated Pu (Pu5c, Pu6c) on α-Pu2O3(111) surface, among which Pu5c is more reactive with lower work-function than Pu6c. Interestingly, H2O and CO2 present the preferential adsorption at the Pu5c sites rather than Pu6c, namely, the site-selective adsorption. H2O tends to dissociate spontaneously and adsorb in cluster as with the coverages increase, while CO2 keeps the molecular state adsorption. The calculated phase diagram and isotherm indicate that the adsorption quantity and stability of H2O are higher than CO2 at the same (T, P) condition, and CO2 can achieve the multilayer adsorption at high pressure (PCO2). This work reveals the chemical heterogeneity of α-Pu2O3(111) surface and the selective adsorption mechanism of active molecules, which clearly depicts the interactions between environment gaseous and Pu-oxide surfaces.

Viscum coloratum is a perennial evergreen, semi-parasitic plant. It is generally used for treating cardiovascular diseases, cancer, hepatitis and hemorrhage. In this study, reliable methods were developed for the qualitative and quantitative analysis of the common constituents in Viscum coloratum and its corresponding host. In the rapid qualitative analysis, a method of ultra-high performance liquid chromatography and quadrupole time-of-flight tandem mass spectrometry was established for identification of the same compounds. Based on the retention times, accurate mass measurement and previous literatures, 23 components were clearly identified by comparison with reference substances. In the quantitative analysis, a method for Viscum coloratum and its corresponding host was developed by ultra-high performance liquid chromatography with triple quadrupole mass spectrometry. 13 common compounds of viscum coloratum and host plants from 19 batches were analyzed with a good linearity (r2≥0.9991), intra-day precision (RSD≤3.24%), inter-day precision (RSD≤3.31%), repeatability (RSD≤2.43%), stability (RSD≤2.63%), and recovery (98.2-102.4%). The overall limits of quantification were less than 5.0ng/mL. The results indicated that these effective and comprehensive methods can be applicable to simultaneous qualitative and quantitative analysis of these common compounds presented in Viscum coloratum and corresponding host plants.

The main polyphenols in mung bean (Vigna radiata L.) seed (MBS), an edible legume with various biological activities, are C-glycosyl flavones (vitexin, isovitexin, isovitexin-6″-O-α-l-glucoside, and dulcinoside). In our study, a validated ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to quantitate the concentrations of four C-glycosyl flavones from MBS extracts in the plasma and various tissues of rats and successfully applied to study their pharmacological profile and tissue distribution in vivo. Four C-glycosyl flavones were rapidly absorbed after oral administration, achieving a Cmax at around 1.5 h, and they could be distributed widely and rapidly in tested tissues. The concentrations of four C-glycosyl flavones in all of the tested tissues decreased obviously in 4 h, which indicated that there was not a trend of long-term accumulation of them. This is the first time to report on pharmacokinetic and tissue distribution studies of four C-glycosyl flavones in rat. The results provided a significative basis for the application of MBS.

The purpose of this study was to compare intestinal permeability between enantiomers of 2-(2-hydroxypropanamido) benzoic acid ((R)-/(S)-HPABA), a marine-derived antiinflammatory drug, using an in situ single-pass intestinal perfusion (SPIP) model in rats. Concentrations, isolated regions of small intestine, and p-glycoprotein (P-gp) inhibitor were performed to investigate their influences on the intestinal absorption of (R)-/(S)-HPABA. In addition, a molecular docking method was performed to illustrate our prediction. The absorption rate coefficients (Ka ) and permeability values (Peff ) of (R)-/(S)-HPABA were calculated. The permeability of (S)-HPABA was significantly (P < 0.01) higher than that of (R)-HPABA in jejunum, and ileum permeability of (R)-/(S)-HPABA appeared best in ileum; the investigated concentrations ranged from 20 to 80 μg/mL, Ka and Peff values of (R)-/(S)-HPABA increased linearly; in the presence of P-gp inhibitor (verapamil), Peff values of two enantiomers were increased significantly; and the effect of P-gp on absorption of (R)-HPABA is stronger than that of (S)-HPABA in ileum segment. Based on these results, carrier-mediated transport or passive transport combined with carrier-mediated transport seems to be the mechanism for intestinal absorption of (R)-/(S)-HPABA, and (R)-/(S)-HPABA may be recognized as the P-gp substrate. In addition, the intestinal permeability of (S)-HPABA is higher than that of (R)-HPABA.

Although the streaked optical pyrometer (SOP) system has been widely adopted in shock temperature measurements, its reliability has always been of concern. Here, two calibrated Planckian radiators with different color temperatures were used to calibrate and verify the SOP system by comparing the two calibration standards using both multi-channel and single-channel methods. A high-color-temperature standard lamp and a multi-channel filter were specifically designed for the measurement system. To verify the reliability of the SOP system, the relative deviation between the measured data and the standard value of less than 5% was calibrated out, which demonstrates the reliability of the SOP system. Furthermore, a method to analyze the uncertainty and sensitivity of the SOP system is proposed. A series of laser-induced shock experiments were conducted at the ‘Shenguang-II’ laser facility to verify the reliability of the SOP system for temperature measurements at tens of thousands of kelvin. The measured temperature of the quartz in our experiments agreed fairly well with previous works, which serves as evidence for the reliability of the SOP system.

The adsorption thermodynamics of active molecules on PuO2 surface are very important for the long-term storage and surface corrosion of Pu. Here, a comparative study is performed within DFT+U-D3 scheme to investigate the adsorption mechanisms, morphology, and phase diagrams of H2O and CO2 on PuO2(1 1 1) surface. The adsorption morphology of H2O will transition from the molecular state to a mixed adsorption state when the coverage is increasing, but CO2 always adsorbs in the molecular state. The differences in adsorption behaviors are mainly due to the hydrogen bonds and Coulomb interactions between the adsorbed molecules. The hydrogen bonds promote the polymolecular adsorption of H2O and the further partial dissociation at high coverage. The Coulomb attractive force among H2O is larger than CO2, and the attractive force among CO2 rapidly decreases as the coverage increases. Unlike the multilayer BET model of H2O adsorption, CO2 adsorption accords with monolayer Freundlich model as revealed by the calculated isotherms. The desorption temperature (Tdes) of H2O and CO2 are agreeing with the experimental results, and the Tdes of H2O is lower than CO2 at the same pressure. This work clarifies the adsorption behaviors of H2O and CO2, and it could provide some important insights into the prediction of the surface corrosion reactions of PuO2 in storage containers.

A sensitive and selective ultra high performance liquid chromatography with tandem mass spectrometry method was established and validated for the simultaneous determination of hydroxy-α-sanshool, hydroxy-β-sanshool, and hydroxy-γ-sanshool in rat plasma after the subcutaneous and intravenous administration of an extract of the pericarp of Zanthoxylum bungeanum Maxim. Piperine was used as the internal standard. The analytes were extracted from rat plasma by liquid-liquid extraction with ethyl acetate and separated on a Thermo Hypersil GOLD C18 column (2.1 mm × 50 mm, 1.9 μm) with a gradient elution system at a flow rate of 0.4 mL/min. The mobile phase consisted of acetonitrile/0.05% formic acid in water and the total analysis time was 4 min. Positive electrospray ionization was performed using multiple reaction monitoring mode for the analytes. The calibration curves of the three analytes were linear over the tested concentration range. The intra- and interday precision was no more than 13.6%. Extraction recovery, matrix effect, and stability were satisfactory in rat plasma. The developed and validated method was suitable for the quantification of hydroxy-α-sanshool, hydroxy-β-sanshool, and hydroxy-γ-sanshool and successfully applied to a pharmacokinetic study of these analytes after subcutaneous and intravenous administration to rats.

The polarons induced by interactions between excess charges and lattice distortions play an important role in surface chemical reactivity of actual oxides. The impacts of electron and hole polarons on H2O and CO2 adsorptions on PuO2(111) surface are investigated by first-principles DFT+U-D3 calculations. Our study reveals that surface and subsurface electron/hole polarons play different roles to H2O and CO2 adsorption. Surface polarons can promote H2O and CO2 adsorption, specifically, electron polarons tend to promote H2O adsorption much more, and hole polarons tend to facilitate CO2 adsorption. We find it interesting that the subsurface electron polaron can promote H2O but depress CO2 adsorption, whereas the subsurface hole polaron play quite an opposite role. Based on a careful study on the electronic and atomic structures of the defective PuO2(111) surfaces, we put forward the inverse modulation mechanism by subsurface electron and hole polarons on H2O and CO2 adsorption, which could shed some light on how to manipulate the molecular adsorption on oxide surfaces.

The in-depth understanding of hydrogen permeation through plutonium-oxide overlayers is the prerequisite to evaluate the complex hydriding induction period of Pu. In this work, the incorporation, diffusion and dissolution of hydrogen in α-Pu2O3 are investigated by the first-principles calculations and ab initio thermodynamic method based on DFT+U and DFT-D3 schemes. Our study reveals that the hydrogen incorporation is endothermic and the separated H atoms prefer to recombine as H2 molecules rather than reacting with α-Pu2O3. The H and H2 diffusion are both feasible, generally, H will recombine first as H2 and then migrate. Both pressure PH2 and temperature T can promote the hydrogen dissolution in α-Pu2O3. The single H2 molecule incorporation and (H + H2) mixed dissolution will successively appear when increasing PH2. Compared to PuO2, this work indicates that Pu sesquioxide is hardly reduced by hydrogen, but the porous α-Pu2O3 facilitates hydrogen transport in Pu-oxide layers. We present the microscopic picture of hydrogen behavior in the defect-free α-Pu2O3, which could shed some light on the study of the hydriding induction period of Pu.

A selective, sensitive and fully validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established for the determination of dihydromyricetin, dihydroquercetin, myricetin and quercetin in rat plasma after intragastric administration of Hoveniae Semen total flavonoids. Baicalin was selected as the internal standard. Analytes were extracted from the rat plasma by protein precipitation with acetonitrile and separated on a C18 chromatographic column (Agilent ZORBAX Eclipse Plus, 4.6 mm × 100 mm, 3.5 μm) using the mobile phase containing acetonitrile (A) and 0.1% formic acid-water (B) by gradient elution at 0.5 mL/min flow rate. A tandem mass spectrometer equipped with an electrospray ionization (ESI) source was used to detect analytes. The analytes were measured by multiple reaction monitoring (MRM) in the negative ionization mode. The lower limit of quantification of dihydromyricetin, dihydroquercetin, myricetin and quercetin were 0.70, 8.16, 1.62 and 0.56 ng/mL, respectively. The accuracy, intra-day and inter-day precision and recovery were all satisfactory and the compounds were stable in rat plasma under all tested conditions. The approach was successfully applied to study pharmacokinetic characteristics of the four bioactive flavonoids in plasma after administering Hoveniae Semen total flavonoids intragastrically to rat. Further investigation was carried out to assess pharmacokinetic comparability of the four bioactive flavonoids after intragastric administration of Hoveniae Semen total flavonoids to mixture of flavonoids.

Incompatible herb pair Gansui-Gancao is recorded in "eighteen incompatible" medicaments in many monographs of TCM (Traditional Chinese Medicine) which means the two herbs can not be co-used in most cases. However, Gansuibanxia decoction composed of Gansui(Kansui), Banxia(Pinellia), Shaoyao(Peony) and Gancao(Liquorice) is a traditional Chinese formula which has been clinically employed for the treatment of cancerous ascites, pleural effusion, peritoneal effusion, etc. The purpose of the study was to investigate the pharmacokinetics of main bioactive components in Gancao to explore the reasons why Gansui-Gancao can be used in Gansuibanxia decoction. A simple, rapid and sensitive UHPLC-MS/MS method for simultaneous determination of liquiritigenin, isoliquiritigenin, liquiritin, glycyrrhetinic acid and glycyrrhizic acid of liquorice in rat plasma was developed and validated. After extraction from plasma, the analytes and internal standard were separated on a C18 column with the mobile phase consisting of 0.1% acetic acid containing 0.2 mM ammonium acetate in water and acetonitrile via gradient elution. The electrospary ionization source was adopted under the multiple reaction monitoring mode. The method was succesfully applied to a comparative pharmacokinetic study of main bioactive components of Gancao in rat plasma after oral administration of the extracts of Gancao (GC), Gansui-Gancao (GS-GC), Shaoyao-Gancao (SY-GC), Gansui-Shaoyao-Gancao (GS-SY-GC) and Gansuibanxia decoction (GSBXD), respectively. The pharmacokinetic parameters had significant differences (P 0.05) in different groups which showed that Gansui decreased the bioavailability of Gancao, while Shaoyao increased the bioavailability of Gancao. Hence, these may be the pharmacokinetic mechanism of incompatible herb pair Gansui-Gancao and the reasons why the herb pair can be used in Gansuibanxia decoction.