Sub-100 ms Level Ultrafast Detection and Near-Infrared Ratiometric Fluorescence Imaging of Norepinephrine in Live Neurons and Brains.

Norepinephrine (NE) is a key neurotransmitter in the central and sympathetic nervous systems, whose content fluctuates dynamically and rapidly in various brain regions during different physiological and pathophysiological processes. However, it remains a great challenge to directly visualize and precisely quantify the transient NE dynamics in living systems with high accuracy, specificity, sensitivity, and, in particular, high temporal resolution. Herein, we developed a series of small-molecular probes that can specifically detect NE through a sequential nucleophilic substitution-cyclization reaction, accompanied by a ratiometric near-infrared fluorescence response, within an impressively short time down to 60 ms, which is 3 orders of magnitude faster than that of present small-molecular probes. A unique water-promoted intermolecular proton transfer mechanism is disclosed, which dramatically boosted the recognition kinetics by ∼680 times. Benefiting from these excellent features, we quantitatively imaged the transient endogenous NE dynamics under external stimuli at the single living neuron level and further revealed the close correlations between NE fluctuations and Parkinson's disease pathology at the level of acute brain slices and live mouse brains in vivo.

Divergent leaf and fine root "pressure-volume relationships" across habitats with varying water availability.

Fine roots and leaves, the direct interfaces of plants with their external environment along the soil-plant-atmosphere continuum, are at the front line to ensure plant adaptation to their growing habitat. This study aimed to compare the vulnerability to water deficit of fine roots and leaves of woody species from karst and mangrove forests-two water-stressed habitats-against that of timber and ornamental woody species grown in a well-watered common garden. Thus, pressure-volume curves in both organs of 37 species (about 12 species from each habitat) were constructed. Fine roots wilted at a less negative water potential than leaves in 32 species and before branch xylem lost 50% of its hydraulic conductivity in the 17 species with available data on branch xylem embolism resistance. Thus, turgor loss in fine roots can act as a hydraulic fuse mechanism against water stress. Mangroves had higher leaf resistance against wilting and lower leaf-specific area than the karst and common garden plants. Their fine roots had high specific root lengths (SRL) and high capacitance to buffer water stress. Karst species had high leaf bulk modulus, low leaf capacitance, and delayed fine root wilting. This study showed the general contribution of fine roots to the protection of the whole plant against underground water stress. Our findings highlight the importance of water storage in the leaves and fine roots of mangrove species and high tolerance to water deficit in the leaves of mangrove species and the fine roots of some karst species.

Kinetin inhibits hepatic stellate cell activation and induces apoptosis via interactions with the TGF-ß1/Smad signaling pathway.

Hepatic fibrosis is the pathological repair response of the liver to chronic injury; hepatic stellate cell (HSC) activation is the central link in the pathogenesis of hepatic fibrosis. Previously, we showed that kinetin, a plant cytokinin hormone, has a protective effect on CCl4-induced liver injury in mice. However, the role of kinetin in liver fibrosis remains unclear. We aimed to study these protective effects and to determine the mechanisms by which kinetin mediates HSC activation and apoptosis. For this purpose, the human HSC line LX-2 was treated with 10 ng/ml transforming growth factor-ß1 (TGF-ß1) for 24 h to stimulate activation. We found that treatment with kinetin at the sub-cytotoxic dose of 40 µg/ml for 48 h reduced the expression of the HSC activation marker α-SMA and inhibited the secretion of extracellular matrix proteins. In addition, kinetin was found to inhibit the proliferation and migration of LX-2 cells. We found that kinetin induced apoptosis in LX-2 cells by increasing the level of cleaved-caspase 3 and the Bax-to-Bcl-2 ratio. Interestingly, these effect were not observed in quiescent HSCs, suggesting that they are activation-dependent. Further study showed that kinetin attenuates activation and promotes apoptosis of LX-2 cells in vitro in part by suppressing the TGF-ß1/Smad signaling pathway.

Dietary supplementation of pyridoxine can enhance the growth performance and improve the protein, lipid utilization efficiency of mandarin fish (Siniperca chuatsi).

This study aimed to assess the effect of pyridoxine supplementation in the mandarin fish diet on growth performance, protein and lipid metabolism, and liver and intestinal histology. Mandarin fish were fed six diets with different levels of pyridoxine (2.67 mg/kg (control), 4.41 mg/kg, 6.57 mg/kg, 10.25 mg/kg, 17.93 mg/kg, 33.12 mg/kg diet) for 8 weeks, and samples were collected for analysis. The findings demonstrated that feeding mandarin fish a diet with 6.57 mg/kg pyridoxine led to a significant increase in weight gain rate (WGR), protein efficiency ratio (PER), whole-body crude protein, whole-body crude lipid, serum protein, cholesterol (CHO), triacylglycerol (TG), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), and alkaline phosphatase (ALP), as well as significantly lower serum glucose (GLU) and feed conversion ratio (FCR), compared to the control group (P < 0.05). Furthermore, we found a significant upregulation of the relative expression of genes associated with hepatic lipid oxidation and synthesis (hl, lpl, pparα, cpt1, cs, srebp1, and fas) and proteolysis (ast, alt, and gdh) in fish fed a diet containing 6.57 mg/kg pyridoxine (P < 0.05). Regarding the histological analysis, we observed a notable decrease in the quantity of intestinal mucus-secreting cells when the fish fed a diet containing 10.25 mg/kg pyridoxine (P < 0.05). These findings suggest that dietary pyridoxine supplementation promotes mandarin fish growth by improving the efficiency of protein and lipid utilization. Additionally, we used a broken-line regression analysis to estimate the optimal dietary pyridoxine requirement for mandarin fish in the range of 6.17-6.41 mg/kg based on WGR, FCR, and PER.

A quantitative study of airway ultrasound in predicting difficult laryngoscopy: A prospective study.

PURPOSE: As common clinical screening tests cannot effectively predict a difficult airway, and unanticipated difficult laryngoscopy remains a challenge for physicians. We herein used ultrasound to develop some point-of-care predictors for difficult laryngoscopy. METHODS: This prospective observational study included 502 patients who underwent laryngoscopy and a detailed sonographic assessment. Patients under 18 years old, or with maxillofacial deformities or fractures, limited mouth opening, limited neck movement or history of neck surgery were excluded from the study. Laryngoscopic views of all patients were scored and grouping using the modified Cormack-Lehane (CL) scoring system. The measurements acquired comprised tongue width, the longitudinal cross-sectional area of the tongue, tongue volume, the mandible-hyoid bone distance, the hyoid bone-glottis distance, the mandible-hyoid bone-glottis angle, the skin-thyrohyoid membrane distance, the glottis-superior edge of the thyroid cartilage distance (DGTC), the skin-hyoid bone distance, and the epiglottis midway-skin distance. ANOVA and Chi-square were used to compare differences between groups. Logistic regression was used to identify risk factors for difficult laryngoscopy and it was visualized by receiver operating characteristic curves and nomogram. R version 3.6.3 and SPSS version 26.0 were used for statistical analyses. RESULTS: Difficult laryngoscopy was indicated in 49 patients (CL grade Ⅲ - Ⅳ) and easy laryngoscopy in 453 patients (CL grade Ⅰ - Ⅱ). The ultrasound-measured mandible-hyoid bone-glottis angle and DGTC significantly differed between the 2 groups (p < 0.001). Difficult laryngoscopy was predicted by an area under the curve (AUC) of 0.930 with a threshold mandible-hyoid bone-glottis angle of 125.5° and by an AUC of 0.722 with a threshold DGTC of 1.22 cm. The longitudinal cross-sectional area of the tongue, tongue width, tongue volume, the mandible-hyoid distance, and the hyoid-glottis distance did not significantly differ between the groups. CONCLUSION: Difficult laryngoscopy may be anticipated in patients in whom the mandible-hyoid bone-glottis angle is smaller than 125.5° or DGTC is larger than 1.22 cm.

Pillar[5]arene-Based Fluorescent Sensor Array for Biosensing of Intracellular Multi-neurotransmitters through Host-Guest Recognitions.

Neurotransmitters are very important for neuron events and brain diseases. However, effective probes for analyzing specific neurotransmitters are currently lacking. Herein, we design and create a supramolecular fluorescent probe (CN-DFP5) by synthesizing a dual-functionalized fluorescent pillar[5]arene derivative with borate naphthalene and aldehyde coumarin recognition groups to identify large-scale neurotransmitters. The developed probe can detect seven model neurotransmitters by generating different fluorescence patterns through three types of host-guest interactions. The obtained signals are statistically processed by principal component analysis, thus the high-throughput analysis of neurotransmitters is realized under dual-channel fluorescence responses. The present probe combines the advantages of small-molecule-based probes to easily enter into living neurons and cross-reactive sensor arrays. Thus, the selective binding enables this probe to identify specific neurotransmitters in biofluids, living neurons, and tissues. High selectivity and sensitivity further demonstrate that the molecular device could extend to more applications to detect and image neurotransmitters.

An Intramolecular Charge Transfer-Förster Resonance Energy Transfer Integrated Unimolecular Platform for Two-Photon Ratiometric Fluorescence Sensing of Methionine Sulfoxide Reductases in Live-Neurons and Mouse Brain Tissues.

Oxidative stress in organisms is a factor leading to a series of diseases including tumors and neurological disorders, while methionine sulfoxide reductases (Msrs) may provide an antioxidant and self-repair mechanism through redox cycles of methionine residues in proteins. Thus, it is important to understand the crucial role of Msrs in maintaining the redox homeostasis. However, it remains a great challenge for real-time and quantitative monitoring of Msrs in live systems due to the lack of appropriate sensing tools. Herein, a novel unimolecular platform integrating the intramolecular charge transfer (ICT) and Förster resonance energy transfer (FRET) dual mechanisms was successfully developed. By employing the highly specific Msrs-catalyzed reduction from the electron-withdrawing sulfoxide moiety in the probe to an electron-donating sulfide group, a synergistic ICT-FRET activation process was achieved, leading to a ratiometric fluorescence response toward Msrs with high selectivity, sensitivity, and accuracy. Moreover, benefiting from the favorable features, including mitochondria-targeting, near-infrared two-photon excitation, low cytotoxicity, good stability, and biocompatibility, the probe was successfully used for monitoring mitochondrial Msrs levels in live-neurons, and a positively correlated up-regulation of endogenous Msrs levels under O2•- stimulation was observed for the first time, confirming a Msrs-involved adaptive antioxidant mechanism in neurons. Furthermore, two-photon microscopic imaging of various regions in Alzheimer's disease (AD) mice brains revealed a down-regulated Msrs levels compared with that in normal brains, especially in the cornuammonis of the hippocampus region, which may in turn lead to an aggravation of AD pathogenesis due to the weakened antioxidant and self-repair capability of neurons.

Genomic Elucidation of a COVID-19 Resurgence and Local Transmission of SARS-CoV-2 in Guangzhou, China.

While China experienced a peak and decline in coronavirus disease 2019 (COVID-19) cases at the start of 2020, regional outbreaks continuously emerged in subsequent months. Resurgences of COVID-19 have also been observed in many other countries. In Guangzhou, China, a small outbreak, involving less than 100 residents, emerged in March and April 2020, and comprehensive and near-real-time genomic surveillance of SARS-CoV-2 was conducted. When the numbers of confirmed cases among overseas travelers increased, public health measures were enhanced by shifting from self-quarantine to central quarantine and SARS-CoV-2 testing for all overseas travelers. In an analysis of 109 imported cases, we found diverse viral variants distributed in the global viral phylogeny, which were frequently shared within households but not among passengers on the same flight. In contrast to the viral diversity of imported cases, local transmission was predominately attributed to two specific variants imported from Africa, including local cases that reported no direct or indirect contact with imported cases. The introduction events of the virus were identified or deduced before the enhanced measures were taken. These results show the interventions were effective in containing the spread of SARS-CoV-2, and they rule out the possibility of cryptic transmission of viral variants from the first wave in January and February 2020. Our study provides evidence and emphasizes the importance of controls for overseas travelers in the context of the pandemic and exemplifies how viral genomic data can facilitate COVID-19 surveillance and inform public health mitigation strategies.

[Diagnosis and treatment of small cell neuroendocrine carcinoma of the prostate].

OBJECTIVE: To explore the clinical manifestations, pathological features and treatment of small cell neuroendocrine carcinoma of the prostate (SCPCa). METHODS: We reported 1 case of SCPCa treated in Jinan People's Hospital and analyzed the clinical data on another 57 cases reported in China. RESULTS: Of the total number of cases, 52 (91.2%) had urinary tract symptoms, including 40 cases of urinary tract obstruction symptoms and 53 (91.2%) had abnormal prostatic nodules on digital rectal examination, 17 (29.8%) with PSA > 4 µg/L. The clinical data on 43 (75.4%) of the cases were valuable for the assessment of clinical stages, including 30 cases with confirmed metastases and another 20 with lymph node and distant metastases. Thirty-seven of the cases (64.9%) were reported with immunohistochemical results, 30 (52.6%) with follow-up data (followed up for 1－24 months, with median survival time of 8 months, and a 1-year survival rate of 16.7%), and another 26 with therapeutic information, 14 treated by chemotherapy, with a median survival time of 11 months and a 1-year survival rate of 28.6%, significantly higher than in the non-chemotherapy groups (P<0.01). CONCLUSIONS: Small cell carcinoma of the prostate is highly malignant with poor prognosis. Its clinical symptoms mainly include urinary tract obstruction, its definite diagnosis chiefly depends on histopathology and immunohistochemistry, and its treatment recommended is chemotherapy-based comprehensive protocol.

NMR Relaxation Dispersion Reveals Macrocycle Breathing Dynamics in a Cyclodextrin-based Rotaxane.

A distinctive feature of mechanically interlocked molecules (MIMs) is the relative motion between the mechanically bonded components, and often it is the functional basis for artificial molecular machines and new functional materials. Optimization of machine or materials performance requires knowledge of the underlying atomic-level mechanisms that control the motion. The field of biomolecular NMR spectroscopy has developed a diverse set of pulse schemes that can characterize molecular dynamics over a broad time scale, but these techniques have not yet been used to characterize the motion within MIMs. This study reports the first observation of NMR relaxation dispersion related to MIM motion. The rotary (pirouette) motion of α-cyclodextrin (αCD) wheels was characterized in a complementary pair of rotaxanes with pirouetting switched ON or OFF. 13C and 1H NMR relaxation dispersion measurements reveal previously unknown exchange dynamics for the αCD wheels in the pirouette-ON rotaxane with a rate constant of 2200 s-1 at 298 K and an activation barrier of ΔF‡ = 43 ± 3 kJ/mol. The exchange dynamics disappear in the pirouette-OFF rotaxane, demonstrating their switchable nature. The 13C and 1H sites exhibiting relaxation dispersion suggest that the exchange involves "macrocycle breathing", in which the αCD wheel fluctuates between a contracted or expanded state, the latter enabling diffusive rotary motion about the axle. The substantial insight from these NMR relaxation dispersion methods suggests similar dynamic NMR methods can illuminate the fast time scale (microsecond to millisecond) mechanisms of intercomponent motion in a wide range of MIMs.

[Scientificity of traditional commodity grade of Chinese medicinal materials--taking Lonicerae Japonicae Flos as example].

Taking Lonicerae Japonicae Flos as an example, the method of "expert consensus of different regions" was used to screen the representative samples and evaluate their commodity grades. The correlation analysis, hierarchical cluster analysis and partial least squares discriminant analysis(PLS-DA) of "commodity grade-appearance characteristic-component content" were carried out to reveal the scientificity of traditional commodity grade of Chinese medicinal material. By referring to the existing literature and the grade investigation from the sample collection regions, 78 "initial grade" samples were screened out from 118 collected samples. Authoritative experts from four regions(n=4) including Linyi(Shangdong province), Bozhou(Anhui province), Anguo(Hebei province) and Beijing were organized to evaluate their commodity grades, separately. Based on the grade consistency rate(R_i≥70%), 69 "local grade" samples were screened out from the "initial grade" samples. Based on the average grade consistency rate ■ "authoritative grade" samples were screened out from the "local grade" samples, including15 first-grade samples, 9 second-grade samples, 11 third-grade samples and 17 fourth-grade samples. For these "authoritative grade" samples, the main appea-rance characteristics were quantified and the contents of 13 components were determined by ultra performance liquid chromatography(UPLC). Furthermore, the total contents of 6 phenolic acids, 4 flavonoids and 3 iridoids were calculated, respectively. The results of correlation analysis showed that 4 appearance characteristics indices were correlated with the commodity grades: color, rate of yellow bars(including blooming flowers), rate of black heads(including black bars), and rate of stems and leaves(including bud debris). Five component content indices were correlated with the commodity grades: chlorogenic acid, isochlorogenic acid C, sweroside, loganin and the total contents of six phenolic acids. Furthermore, chlorogenic acid, loganin and the total contents of six phenolic acids showed significantly negative correlation with the main appearance characteristics, indicating that the appearance characteristics of Lonicerae Japonicae Flos can reflect its internal quality, and these 3 indices can be used as quality markers(Q-markers). The results of hierarchical cluster analysis showed that the samples of four grades were classified into four categories, and the samples with the same grades and the same categories accounted for 80.8% of the total samples, while the samples with the different grades were obviously classified into different categories. The results of PLS-DA analysis showed that the samples of different grades showed obvious intragroup aggregation and intergroup dispersion. The above results indicated that it was feasible to evaluate the traditional commodity grade of Lonicerae Japonicae Flos by the method of "expert consensus of different regions". For the evaluation of traditional commodity grade of Chinese medicinal material, the samples should be representative, expert conclusions should have enough consensuses, and grade determination should be authoritative. As the crystallization of clinical experience, traditional commodity grade can scientifically reflect the internal quality of Chinese medicinal material.

[Quality evaluation of Poria based on specific chromatogram and quantitative analysis of multicomponents].

HPLC specific chromatograms of Poria were established, and the concentrations of 10 triterpenoids(16α-hydroxydehydrotrametenolic acid, poricoic acid B, dehydrotumulosic acid, poricoic acid A, polyporenic acid C, poricoic acid AM, 3-O-acetyl-16α-hydroxydehydrotrametenolic acid, dehydropachymic acid, pachymic acid, and dehydrotrametenolic acid) were simultaneously determined. Chromatographic analysis was conducted on a Welch Ultimate XB C_(18) column(4.6 mm × 250 mm,5 µm). Acetonitrile solution(contain 3% tetrahydrofuran)(A) and 0.1% formic acid aqueous solution(B) were used as the mobile phase with gradient elution at a flow rate of 1.0 mL·min~(-1). The column temperature was 30 ℃ and the injection volume was 20 µL. The experimental data were analyzed by the SPSS 22.0 and GraphPad Prism 7.0. The established triterpenoids fingerprints were specific, and the 10 components were well separated and showed good linearity(r≥0.999 6) within the concentration ranges tested. The mean recoveries were between 98.53%-103.8%(RSD 1.7%-2.7%). The method was specific and repeatable, and could be used for identification and quality evaluation of Poria. The results showed that the contents of 10 triterpenoids were positively correlated with each other. The contents of 10 triterpenoids of samples collected from producing areas were higher than that collected from markets. The total contents of 10 triterpenoids of samples collected from Hubei and Yunnan province were slightly higher than that from Anhui province, but the contents of samples from Anhui province were varied in smaller ranges.

New tetralactam hosts for squaraine dyes.

The photophysical properties of a deep-red fluorescent squaraine dye can be improved by encapsulating it within a tetralactam macrocycle. Three new tetralactams are described with different substituents (methyl, methoxy, methylenedioxy) on the macrocycle aromatic sidewalls. The capability of each tetralactam to encapsulate a squaraine dye in chloroform solution was determined experimentally using absorption, fluorescence, and NMR spectroscopy. Two of the tetralactams were found to thread a squaraine dye with association constants on the order of 106 M-1, while a third macrocycle exhibited no squaraine affinity. An X-ray crystal structure of the third tetralactam showed that the substituents sterically blocked squaraine association. Of the two tetralactams that encapsulate a squaraine, one induces an increase in squaraine fluorescence quantum yield, while the other quenches the squaraine fluorescence. The results suggest that these new squaraine binding systems will be useful for biological imaging and diagnostics applications.

Flavonol glycosides from the fruits of Evodia rutaecarpa.

Two new flavonol glycosides, limocitrin 3-O-ß-D-xylopyranosyl(1→2)-ß-D-glucopyranoside (1) and limocitrin 3-O[2-O-ß-D-xylopyranosyl-6-O-α-L-rhamnopyranosyl]-ß-D-glucopyranoside (2), together with eight known analogs (3-10), were isolated from the fruits of Evodia rutaecarpa. Their structures were elucidated on the basis of spectroscopic analyses and chemical evidences. Meanwhile, Nrf2 inducing abilities of seven isolated compounds were evaluated, and compounds 1, 2, 6, 7, and 8 exhibited moderate effect on Nrf2.

Multicolor Photoluminescence Including White-Light Emission by a Single Host-Guest Complex.

Achieving multicolor photoluminescence, especially white-light emission, under mild conditions based on a single fluorescent compound is a great challenge. Herein, we report a novel colorful-emission host-guest complex BPCY, which is composed of a two-arm fluorescent guest molecule (BPC) and γ-cyclodextrin (γ-CD) as the host molecule. BPC bears a unique asymmetrical donor-acceptor-donor (D1-A+∼D2)-type structure, where D1, A+, and D2 stand for the binaphthol electron donor, pyridinium electron acceptor, and coumarin electron donor, respectively. The luminescence property of BPC shows dual-sensitivity, i.e., toward the excitation wavelength and the cyclodextrin host molecule. Under certain conditions, the complex shows three different emission wavelengths, allowing the realization of multicolor photoluminescence, including red (R), green (G), and blue (B) as well as various intermediate colors by orthogonally modulating these two stimuli. In this way, nearly pure white-light emission with CIE coordinates (0.33, 0.34) could be generated. A combination of structural, spectroscopic, and computational simulation studies revealed the occurrence of synergetic mechanistic processes for the stimuli-responsive multicolor luminescence of the BPCY complex, namely, host-enhanced intramolecular charge-transfer (ICT) and host-induced restriction of intramolecular rotation (RIR). This new supramolecular complex with superior multicolor emission abilities may find wide applications in the fields of information processing and display media. Furthermore, the molecular design rationale presented here may provide a new design strategy for the development of high performance optical materials using a single supramolecular platform.

[Absorption characteristics of alkaloids in Fuzheng Xiaozheng Fang by rat everted intestinal sac models].

Everted intestinal sac models were used to investigate the intestinal absorption of the 4 alkaloids(berberine, palmatine, coptisine, and epiberberine) in Fuzheng Xiaozheng Fang(FZ) at different intestine segments. The absorption parameters of each component were calculated; SPSS 20.0 software was used to analyze the data and evaluate the absorption characteristics at different intestinal segments. The results showed that all the four active ingredients conformed to zero-order absorption rate. There was significant difference in absorption rate constant (Ka) between the four ingredients at low dose and medium and high dose groups(P<0.05), but there was no significant difference in Ka between medium dose and high dose. The absorption mechanization of four ingredients presented two absorption manners： positive diffusion and passive absorption. The absorptive amount of 4 alkaloids in ileum was slightly greater than that of jejunum, but no significant differences were observed, which indicated that these four alkaloids had no specific absorption windows in intestinal segment.

Chemical constituents of Euonymus fortunei.

A new flavonol glycoside, kaempferol-3-O-ß-D-(2-O-E-p-coumaroyl)-glucopyranosyl-7-O-α-l-rhamnopyranoside (1), along with eleven known compounds including five flavonol glycosides (2-6), one phenolic glycoside (7), two megastigmane glycosides (8 and 9), two triterpenoids (10 and 11) and one alditol (12), was isolated from the aerial parts of Euonymus fortunei. Their structures were determined on the basis of spectroscopic analysis and chemical evidence. Compounds 2-4, 7, 8, and 10-12 were evaluated their antimicrobial activities against Ureaplasma urealyticumin vitro, but all tested compounds have no useful activities against Ureaplasma urealyticum.

[Study on antioxidant chemical constituents of Lonicera japonica leaves].

Guided by the antioxidant activity, the EtOAc-soluble and n-butanol-soluble fractions of the 50% methanol extract of Lonicera japonica leaves were isolated and purified by various chromatorgraphic methods, and the structures were identified by spectral analysis and comparison to the data reported in literature. As a result, nine compounds were obtained and identified as 5-O-caffeoylquinicacid (1), chlorogenicacid (2), 4-O-caffeoylquinicacid (3), luteolin-7-O-[α-L-arabinopyranosyl-(1 --> 6)] -ß-D-glucopyranoside (4), luteoloside (5), 3,4-di-O-caffeoylquinic acid (6), 3,5-di-O-caffeoylquinic acid (7), 4, 5-di-O-caffeoylquinic acid (8) and luteolin (9). The antioxidant activity of the nine compounds were determined by using DPPH free radical scavenging method, and ascorbic acid was used as a positive control. Their antioxidant activities from high to low were 5 > 9 > 2 > 8 > 7 > 6 > 1 > 3 > 4. Among them, luteoloside (5) had the strongest antioxidant activity with an IC50 of 0.018 18 g x L(-1), and luteolin (IC50 0.023 6 g x L(-1)) and chlorogenicacid (IC50 0.035 17 g x L(-1)) ranks No. 2 and 3. Furthermore, the antioxidant activity of luteoloside and luteolin were stronger than that of ascorbic acid (IC50 0.027 54 g x L(-1)). These results gave a basis for the further study and utilization of L. japonica leaves.

[Study on quality standard of Sophora flavescens root extract].

As a part of the project for the Chinese Pharmacopoeia (2015 edition), the quality standard of Sophora flavescens root extract was investigated and established. According to the methods described in the Appendix of Chinese Pharmacopoeia (2010 edition), the water and ash inspections were carried out. The marker components trifolirhizin, sophoraflavanone G, oxymatrine and oxysophocarpine in the samples were identified by qualitative TLC. The determination of oxymatrine, matrine, oxysophocarpine and sophocarpine was conducted by HPLC and the total flavonoids were measured by ultraviolet spectrophotometry, using sophoraflavanone G as reference substance. The results indicated the spots on the plate were clear with good resolution and the contents of oxymatrine, matrine, oxysophocarpine and sophocarpine in the 13 batches of the samples were 3.87% - 11.1%, 0.970% - 4.33%, 1.30% - 2.59% and 0.260% - 1.14%, respectively. The total flavoids in the 13 batches of the samples were 3.88% - 7.93%. In the study, the validated methods were reproducible and the established quality standard was feasible, which could be used for the quality control of S. flavescens root extract and related preparations.

[Research on quality standards of Euonymus fortunei].

To establish quality standards of Euonymus fortunei, and supply scientific evidence for the quality control of Euonymus fortunei. Empirical and microscopic identification methods were adopted to observe morphological and histological characters. The contents of water, total ash, acid-insoluble ash and alcohol-soluble extractive were analysed according to the methods of Chinese Pharmaco- poeia (2010). Dulcitol and reference herbs were used to identify materia medica of Euonymus fortunei by TLC method. The total flavonol glycosides contents were analysed by HPLC method, using quercetin and kaempferol as reference substances. Quercetin and kaempferol were separated on a C18 column (4.6 mm x 250 mm, 5 µm) with methanol-0.1% formic acid(51:49) as the mobile phase and detected at 366 nm. The flavonoid aglycones content was then multiplied by a conversion coefficient, and the result was the total flavonol glycosides content. The macroscopical identification, microscopic features and TLC methods were proper. The average contents of water, total ash, acid-insoluble ash, alcohol-soluble extractive and total flavonol glycosides were 8.76%, 6.48%, 0.31%, 17.48% and 0.211% , respectively. The quality standards established on the basis of the research results were suitable for the quality evaluation of Euonymus fortunei.