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Plant-based natural products represent an alternative to chemical compounds for the control of mites in veterinary medicine. Here, the essential oil of Elsholtzia densa (E. densa) Benth was extracted using hydrodistillation at a rate of 1.2%. The chemical composition of the essential oil was determined by gas chromatographymass spectrometry (GC-MS) analysis. The GC-MS analysis indicated that the principal compounds in the volatile oil of the sample were 4-Pyridinol (28.16%) and thymol (26.58%). The acaricidal activity of E. densa oil against Sarcoptes scabiei (S. scabiei) was tested in vitro. Toxicity test data were analysed using a complementary log-log (CLL) model. The E. densa oil was prepared in five concentrations by dilution with liquid paraffin (1, 2, 4, 8 and 16 mg/ml) and exhibited strong toxicity against S. scabiei with LT50 values of 16.637, 5.075, 2.884, 1.184 and 0.760 h, respectively. The LC50 values were 7.678, 4.623, 2.543, 1.502, 1.298 and 0.981 mg/ml for S. scabiei at 1, 2, 4, 8, 16 and 24 h, respectively. Compared to the control, the essential oil showed significant effects against S. scabiei in vitro. At 16 mg/ml, E. densa oil was found to kill all mites within a 16-h period. The results indicate that E. densa oil possesses potential acaricidal activity in vitro and may be exploited as a novel drug for the effective control of S. scabiei. [ABSTRACT FROM AUTHOR]

A quantitative analytical method of ultra-high performance liquid chromatography (UPLC) was developed for simultaneously determining twelve components in Tibetan medicine Zuozhu Daxi. SIMPCA 12.0 software was used a principal component analysis PCA) and partial small squares analysis (PLSD-DA) on the twelve components in 10 batches from four pharmaceutical factories. Acquity UPLC BEH C15 column (2.1 mm x 100 mm, 1.7 µm) was adopted at the column temperature of 35 °C and eluted with acetonitrile (A) -0.05% phosphate acid solution (B) as the mobile phase with a flow rate of 0. 3 mL · min(-1). The injection volume was 1 µL. The detection wavelengths were set at 210 nm for alantolactone, isoalantolactone and oleanolic; 260 nm for trychnine and brucine; 288 nm for protopine; 306 nm for protopine, resveratrol and piperine; 370 nm for quercetin and isorhamnetin. The results showed a good separation among index components, with a good linearity relationship (R2 = 0.999 6) within the selected concentration range. The average sample recovery rates ranged between 99.44%-101.8%, with RSD between 0.37%-1.7%, indicating the method is rapid and accurate with a good repeatability and stability. The PCA and PLSD-DA analysis on the sample determination results revealed a great difference among samples from different pharmaceutical factories. The twelve components included in this study contributed significantly to the quantitative determination of intrinsic quality of Zuozhu Daxi. The UPLC established for to the quantitative determination of the twelve components can provide scientific basis for the comprehensive quality evaluation of Zuozhu Daxi.

• MnFe2O4/MoS2 nanocomposites were prepared by a sonochemical method. • MoS2 nanosheets were exfoliated and decorated homogeneously with MnFe2O4 nanoparticles. • Mesoporous structure with specific surface area of 97.16 m2/g. • Superparamagnetic behavior with saturation magnetization of 37.4 Am2/kg.<br>This study established a facile one-step strategy to anchor MnFe2O4 nanoparticles on the surface of MoS2 nanosheets in a controlled manner. The as-prepared MnFe2O4/MoS2 nanocomposites were investigated by TEM, XRD, XPS, Raman, BET and VSM in detail. The MnFe2O4 nanoparticles with an average particle size of 26 nm were densely and uniformly decorated on MoS2 nanosheets, and consequently, both the aggregation of MnFe2O4 nanoparticles and restacking of MoS2 nanosheets were effectively prevented. More importantly, the MnFe2O4/MoS2 nanocomposites exhibited high specific surface area, typical superparamagnetic behavior and excellent solution dispersion, showing a great potential for biomedical applications in the fields of magnetic resonance imaging, targeted drug delivery and tumor hyperthermia.

The study aims at providing a new suitable way to promote artificial cultivation, solving the problem of resources increasingly endangered wild medicine, and protecting the wild resources of Tibetan medicine. The content of quercetin,kaempferol and isorhamnetin was determined by HPLC. The correlation between flavonoids components and ecological factors was analyzed using partial least-squares regression (PLSR). Based on Maxent model combining using ArcGIS software, suitable regionalization for H.rhamnoides subsp. sinensis was studied.The results showed that the difference of quercetin,kaempferol and isorhamnetin content in samples from different regions were obvious. The main factors effecting quercetin content accumulation were the altitude andthe average monthly precipitation in January and August. The main factors effecting kaempferol accumulation were the altitude andthe average monthly precipitation in the coldest quarter and December. The main factors effecting isorhamnetin accumulation were the average monthly precipitation in August, January and the coldest quarter.The regional distribution suitability index for H.rhamnoides subsp. sinensis was 0-0.708. The suitable area 590 500 km², accounting for 6.13% of the total area. The preferably suitable area was 552 500 km², accounting for 5.73% of the total area.The methods used in the study is simple and feasible, the result is reliable which provide a new approach for Tibetan medicine resources sustainable exploitation and utilization.

AIM: To determine if yoga as a complementary and alternative therapy was associated with enhanced health and treatment-related side effects in patients with breast cancer. This systematic review examines whether yoga practice provides any measurable benefit, both physically and psychologically, for women with breast cancer. METHODS: PubMed, EMBASE and the Cochrane Library for randomized controlled trials (RCTs) throughout June 2013. We evaluated the quality of the included studies by the Cochrane Handbook 5.2 standards and analyzed the data using the Stata software, version 10.0. Meta-regression and subgroup analysis were also performed to identify additional predictors of outcome and to assess heterogeneity. RESULTS: Sixteen RCTs with a total of 930 participants were included. Comparing yoga groups to control groups, there was a statistically significant difference in overall health-related quality of life, depression, anxiety and gastrointestinal symptoms. Meta-regression analyses revealed that the duration of yoga practice and type of control group partly explained the heterogeneity. Subgroup analyses revealed that yoga had a positive effect on anxiety only when it had been practiced for longer than 3 months. Only the wait-list control group showed an effect of yoga on physical well-being. CONCLUSION: The current evidence demonstrates that yoga practice could be effective in enhancing health and managing some treatment-related side effects for patients recovering from breast cancer. In future clinical studies, clinicians should consider the patient's wishes along with the current best evidence of the effects of yoga practice in their clinical decision-making.

Objective: This study aimed to observe curative effect of low load aerobic Yoga-based exercise in cotherapy with inhalation of air negative oxygen ions on occupational patient with cotton pneumoconiosis s. Methods: Select 60 female patients with occupational cotton pneumoconiosis aged between 30 and 50 and randomly divide them into an observation group and a control group with each group consisting of 30 patients. The patients in the control group do low load aerobic Yoga-based exercise for the purpose of improving their physical and respiratory functions, while the patients in the observation group accept co-therapy that combines inhalation of air negative oxygen ions with Yoga exercise. Respectively test and compare the clinical signs and pulmonary function indicators of the two groups of patients at the time of their selection and after 3 months' treatment. Results: after 3 months' treatment, the pulmonary function indicators of the two groups of patients are significantly improved in comparison with their counterparts before the treatment (P<0.05), while the improvement of the pulmonary function and the clinical curative effect of the observation group are more obvious when compared with their counterparts before the treatment or those of the control group, P<0.05. The difference between the improvements shows statistical significance. Conclusion: low load aerobic exercise in the normal air environment can improve lung function of the patient indeed, however, the curative effect is more significant if the exercise is done in the environment with higher air negative oxygen ion content.

In order to find new anticancer drugs, a series of novel furoxan-based coumarin derivatives (<i>10a</i>-<i>k</i>) were synthesized and evaluated for their antiproliferative activities in vitro. All compounds displayed more potent inhibition on human cervical cancer HeLa cell proliferation than coumarin-3-carboxylic acid, and compounds <i>10b</i>,<i> 10c</i>,<i> 10f</i>,<i> 10h</i>, and <i>10i</i> with IC<sub>50</sub> values ranging from 0.88 to 5.95 μM were even stronger than doxorubicin (IC<sub>50</sub> = 10.21 μM). The further study showed that compound <i>10i</i> exerted the highest antiproliferative activity (IC<sub>50</sub> = 0.60 μM) against human breast cancer MCF-7 cells, and compound <i>10f</i> had broader spectrum antiproliferative activity against five cancer cells with IC<sub>50</sub> values in the low micromolar range of 1.86-9.85 μM. More interestingly, compound <i>10f</i> had little effect on normal intestinal epithelial CCD841 cells. Our findings suggest that these novel furoxan-based coumarin derivatives may provide a new framework for the discovery of novel antitumor agents for the intervention of human carcinoma cells.

A new fluorescent labeling reagent, benzimidazo[2,1-<i>b</i>]quinazolin-12(6<i>H</i>)-one-5-ethyl-<i>p</i>-toluenesulfonate (BQETS) was designed and synthesized, and it was successfully applied to the determination of fatty acids with liquid chromatography. BQETS can easily and quickly label fatty acids within 20 min at 90 °C in dimethylformamide with K<sub>2</sub>CO<sub>3</sub> as catalyst. The derivatives exhibit high stability and strong fluorescence with excitation and emission wavelengths of 247 and 401 nm, respectively. The 24 derivatives of fatty acids were completely separated by gradient elution on a Hypersil GOLD C18 column. Excellent linear responses for all fatty acids were observed with correlation coefficients of >0.9991. The method also showed good sensitivity and precision, with limits of detection in the 0.0024-0.0206 μg g<sup>−1</sup> range and relative standard deviations ≤9.6 %. This is the first time that BQETS fluorescent probe and its applications for the determination of fatty acids have been reported. Moreover, this is the first report on the comparison of free fatty acids composition in the above-ground part of <i>Coriandrum sativum</i> L. from different habitats in China.

Chemical isotope labelling in combination with high-performance liquid chromatography-tandem mass spectrometry (CIL-HPLC-MS/MS) is a powerful method for quantitative profiling of targeted molecules. In the current work, we successfully developed a novel CIL-HPLC-MS/MS method for quantitative profiling of residual organophosphorus thioester pesticides (OPTPs) in agricultural products through the determination of the cleavage products of thiol (CP-thiol) compounds. In this method, we synthesized a novel pair of CIL reagents, i.e., N-(4-(carbazole-9-yl)-phenyl)-N-maleimide (NCPM-d0) and its deuterated analogue NCPM-d2, both of which contain a maleimide moiety as the reactive group and an isotope tag to sensitively label CP-thiol compounds. NCPM-d0 was used to label CP-thiol compounds cleaved from OPTPs in the investigated agricultural product samples, and NCPM-d2 was used to label CP-thiol compounds cleaved from OPTPs in the standard substance-spiked organic agricultural product samples. The heavily labelled derivatives were used as the internal standards (ISs) to compensate for the matrix effects during MS analysis. The NCPM-d0- and NCPM-d2-labelled derivatives generated two characteristic product ions (PIs) at m/z 372.5 and 374.5 under collision induced dissociation, respectively, which are used to establish the multiple reaction monitoring (MRM) mode-based detection. The precursor ions of NCPM-d0 and NCPM-d2 labelled derivatives of CP-thiol compounds were deduced according to the structures of the OPTPs. The peak pairs with a fixed mass difference and similar retention times were assigned as potential CP-thiol candidates for the identification of the corresponding OPTPs. Using the proposed method, we successfully determined seven residual OPTPs in agricultural product samples. Taken together, the presented method was demonstrated to be a promising new technique in the quantitation of OPTPs in agricultural product samples with high reliability.

This study is aimed to establish a high-performance liquid chromatography (HPLC) method for simultaneous determination of skimmin, scopolin and umbelliferone in Saussurea hieracioides. Samples were analyzed on a Wondasil C18-WR column (4.6 mm x 250 mm, 5 microm) with methanol (A) and water containing 0.1% phosphate (B) as mobile phases for gradient elution at a flow rate of 1.0 mL x min(-1). The detection wavelength and column temperature were set at 325 nm and 35 degrees C, respectively, and the sample size was 10 microL. The results showed that skimmin, scopolin and umbelliferone were simultaneously achieved within 40 min under the above conditions. A good linearity was observed in the range of 0.18-5.6 microg (r = 1.000 0), 0.060-1.8 microg (r = 0.999 9), 0.032-0.97 microg (r = 0.999 8) for skimmin, scopolin and umbelliferone, respectively, with the average recoveries of 99.16% (RSD = 0.41%), 100.3% (RSD = 0.79%), 102.2% (RSD = 0.87%). The method is simple, accurate and reproducible and can be used for the quality control of S. hieracioides.

The mercury in Tibetan medicine has become important focus in the research on medicine safety evaluation. The total mercury and the ionic mercury in artificial gastric juice of Tibetan medicine Dangzuo were detected by Gold Amalgam Enrichment-Atomic Fluorescence Spectrometry (GAE-AFS). In the present study, Tibetan medicine Dangzuo was prepared by H2SO4-KNO3 digestion system and artificial gastric juice. The established method and condition of instrument were investigated. Under the optimum experimental conditions and instrumental operation parameters, the recovery (n=6) of HgS is 99.56$ (RSD = 1.94%), the limit of detection for mercury is 0.2 ng x L(-1), the linear range is 0-500 ng x L(-1), and r = 0.9999. Then, the total mercury and the ionic mercury in artificial gastric juice in Dangzuo samples from different Tibetan regions were assayed. The result showed that the ranges of total mercury and ionic mercury in artificial gastric juice were 3.9980-16.7358 x mg x g(-1) and 45.5377-1033.9850 ng x g(-1), respectively. The analytical method mentioned above is rapid and accurate for determining the amount of mercury in Tibetan medicine Dangzuo.

A novel and interesting pre-column derivatisation method was developed for the analysis of triterpenic acids by high-performance liquid chromatography (HPLC) with fluorescence detection. Each triterpenic acid produced two HPLC peaks with similar peak areas after derivatising with chiral 1-(9H-carbazol-9-yl) propan-2-yl-methanesulfonate (CPMS), while the fatty acid derivative of CPMS had only one peak. This phenomenon greatly increased the confidence in analyte confirmation. Compound with only one peak or two peaks differing greatly in their peak areas could be excluded from the target compound list. CPMS was compared with five other derivatising reagents, four of which produced only one peak for one triterpenic acid, to study the possible mechanism. Analytes with different behaviours were also studied to better interpret the mechanism. The proposed method also showed the merits of high sensitivity and less sample consumption. It was successfully applied to the analysis of triterpenic acids in fruit peels and flesh. There is no prior report on the two peak phenomenon of triterpenic acids. The information provided in this study will be helpful for those who are also engaged in derivatisation study.

OBJECTIVE: To establish the HPLC fingerprint for Halenia elliptica herbs, a traditional Tibetan medicine, in order to study constituents contained in H. elliptica from different habitats and compare their differences.METHOD: HPLC analysis was made on a Welchrom-C18 (4.6 mm x 250 mm, 5 microm) with water and acetonitrile as mobile phase. The wavelength was detected as 265 nm, the flow rate was 1.0 mL x min(-1), and the column temperature was 40 degrees C. The software for chromatographic fingerprint was applied to analyze the similarity. And principal component analysis was conducted. RESULT: Twelve common chromatographic peaks were identified by fingerprint, showing a low similarity in constituent and variety. The significant difference in the proportion between xanthones and aglycones in each batch of herbs indicated no notable correlation between constituent characteristics and geographic locations of habitats. CONCLUSION: The method is so simple, exclusive, stable and highly repeatable that it can provide reference for identification and quality assessment of H. elliptica herbs.

Guilt and shame are usually evoked during interpersonal interactions. However, no study has compared guilt and shame processing under such circumstances. In the present study, we investigated guilt and shame in an interpersonal context using functional magnetic resonance imaging (fMRI). Behaviorally, participants reported more “guilt” when their wrong advice caused a confederate's economic loss, whereas they reported more “shame” when their wrong advice were correctly refused by the confederate. The fMRI results showed that both guilt and shame activated regions related to the integration of theory of mind and self-referential information (dorsal medial prefrontal cortex, dmPFC) and to the emotional processing (anterior insula). Guilt relative to shame activated regions linked with theory of mind (supramarginal gyrus and temporo-parietal junction) and cognitive control (orbitofrontal cortex/ventrolateral prefrontal cortex and dorsolateral prefrontal cortex). Shame relative to guilt revealed no significant results. Using multivariate pattern analysis, we demonstrated that in addition to the regions found in the univariate activation analysis, the ventral anterior cingulate cortex and dmPFC could also distinguish guilt and shame. These results do not only echo previous studies of guilt and shame using recall and imagination paradigms but also provide new insights into the psychological and neural mechanisms of guilt and shame.

ETHNOPHARMACOLOGICAL RELEVANCE: Dioscorea zingiberensis C. H. Wright (D. zingiberensis), Dioscoreaceae, is used extensively in traditional Chinese medicines. The aim of the current review paper is to give a comprehensive overview of the traditional usage and phytochemistry of the plant. Clinical studies performed and products prepared from the plant and active principles will be mentioned. In addition a review of the taxonomy of the genus Dioscorea is given.MATERIALS AND METHODS: A systematic search on literature has been performed in databases like Google Scholar, Science Direct, Scifinder, Web of Science, and in Chinese databases (China Knowledge Resource Integrated, i.e., CNKI and Wanfang) including Ph.D. and M.Sc. dissertations. These from the period 1983-2016 have been searched. RESULTS: D. zingiberensis is an endemic plant in China widely distributed in some provinces, especially Hubei and Shaanxi. The rhizomes are the medicinal part in Dun-Ye-Guan-Xin-Ning tablets and are used for isolation of diosgenin. Steroidal saponins are believed to be the active principles. More than 70 compounds have been identified. Several of these have been tested in preclinical assays and clinical trials. A wide spectrum of biological effects including cardiovascular, anti-thrombosis, hyperlipidemia, neuroprotection, anti-inflammatory, and anthelmintic effect has been verified. CONCLUSIONS: Because of the promising results from the investigations on the plant material of D. zingiberensis, further in depth analyses ought to be performed to evaluate its potential as either a traditional drug or a source of bioactive principle. The presently performed studies do not explain mechanism of action, pharmacokinetics (ADME properties), or toxicity. All of these topics need more elaborate investigations.

Agroforestry system, as the most promising substitute plantation approach, has been widely regarded as a prominent strategy for mitigating the conflicts between rapid growing population and limited arable land resources. This paper aims to screen the optimal planting pattern for <i>Gentiana rigescens</i> base on the content of gentiopicroside, providing the scientific basis for sustainable supply and application of this plant. Generally, Fourier transform infrared (FTIR) spectroscopy is effective to integrally monitor and reflect the whole constituents of natural materials. FTIR combined with chemometrics was used for distinguishing the <i>G. rigescens</i> from different compound planting models in this research. The result of partial least square discriminant analysis implied that planting year of <i>G. rigescens</i> had a greater impact on the content of gentiopicroside than that of <i>Camellia sinensis</i>. The gentiopicroside content in 1.5- or 2-year-old <i>G. rigescens</i> was higher. Wavelet denoising was effective for the classification. Samples which had higher contents of gentiopicroside were clustered together relatively, while those with lower contents of gentiopicroside were classified into the other large category. Our investigation revealed that <i>G. rigescens</i> can be successfully cultivated with <i>C. sinensis</i>, which met the requirement of the gentiopicroside content recommended by Pharmacopoeia of the People’s Republic of China. That 2-year-old <i>G. rigescens</i> grown with 12-year-old <i>C. sinensis</i> was the optimal compound planting pattern, according this study. The present study provided the optimal compound planting pattern of <i>G. rigescens</i>, which is helpful for improving land-use efficiency and economic returns.

DNA barcoding, the identification of species using one or a few short standardized DNA sequences, is an important complement to traditional taxonomy. However, there are particular challenges for barcoding plants, especially for species with complex evolutionary histories. We herein evaluated the utility of five candidate sequences - rbcL, matK, trnH-psbA, trnL-F and the internal transcribed spacer (ITS) - for barcoding Rhodiola species, a group of high-altitude plants frequently used as adaptogens, hemostatics and tonics in traditional Tibetan medicine. Rhodiola was suggested to have diversified rapidly recently. The genus is thus a good model for testing DNA barcoding strategies for recently diversified medicinal plants. This study analyzed 189 accessions, representing 47 of the 55 recognized Rhodiola species in the Flora of China treatment. Based on intraspecific and interspecific divergence and degree of monophyly statistics, ITS was the best single-locus barcode, resolving 66% of the Rhodiola species. The core combination rbcL+matK resolved only 40.4% of them. Unsurprisingly, the combined use of all five loci provided the highest discrimination power, resolving 80.9% of the species. However, this is weaker than the discrimination power generally reported in barcoding studies of other plant taxa. The observed complications may be due to the recent diversification, incomplete lineage sorting and reticulate evolution of the genus. These processes are common features of numerous plant groups in the high-altitude regions of the Qinghai-Tibetan Plateau.

DNA barcoding, the identification of species using one or a few short standardized DNA sequences, is an important complement to traditional taxonomy. However, there are particular challenges for barcoding plants, especially for species with complex evolutionary histories. We herein evaluated the utility of five candidate sequences - rbcL, matK, trnH-psbA, trnL-F and the internal transcribed spacer (ITS) - for barcoding Rhodiola species, a group of high-altitude plants frequently used as adaptogens, hemostatics and tonics in traditional Tibetan medicine. Rhodiola was suggested to have diversified rapidly recently. The genus is thus a good model for testing DNA barcoding strategies for recently diversified medicinal plants. This study analyzed 189 accessions, representing 47 of the 55 recognized Rhodiola species in the Flora of China treatment. Based on intraspecific and interspecific divergence and degree of monophyly statistics, ITS was the best single-locus barcode, resolving 66% of the Rhodiola species. The core combination rbcL+matK resolved only 40.4% of them. Unsurprisingly, the combined use of all five loci provided the highest discrimination power, resolving 80.9% of the species. However, this is weaker than the discrimination power generally reported in barcoding studies of other plant taxa. The observed complications may be due to the recent diversification, incomplete lineage sorting and reticulate evolution of the genus. These processes are common features of numerous plant groups in the high-altitude regions of the Qinghai-Tibetan Plateau.

The majority of studies on the development of theory of mind (ToM) have focused on the preschool years. The current study examined the impact of conversation-based ToM training and whether a battery of executive function (EF) performance can predict the improvement in Chinese elementary students' ToM from training. A conversation-based training program was implemented for one month and evaluated with pre- and posttest measures of ToM. Ninety-six children were randomly assigned to intervention (nþinspace=þinspace49) and control groups (nþinspace=þinspace47). Findings indicate that the intervention group demonstrated significantly greater gains in ToM than the control group and that individual differences in a battery of EF performance can predict the improvement of ToM. These results are consistent with the beliefs that conversations about the mind foster improvements in theory of mind in school-aged children, and executive functioning skills can assist school-age children in constructing ToM by facilitating the ability to learn from relevant experience.

• A new low toxic dual-UADLLME coupled with microwave-assisted derivatization was proposed. • 4′-Carboxy-substituted rosamine was firstly used as derivatization reagent. • Simultaneous determination of PPD and PPT in rat plasma was achieved by UHPLC-MS/MS. • This method was successfully applied to pharmacokinetics study.<br>This paper, for the first time, reported a speedy hyphenated technique of low toxic dual ultrasonic-assisted dispersive liquid-liquid microextraction (dual-UADLLME) coupled with microwave-assisted derivatization (MAD) for the simultaneous determination of 20(<b>S</b>)-protopanaxadiol (PPD) and 20(<b>S</b>)-protopanaxatriol (PPT). The developed method was based on ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) detection using multiple-reaction monitoring (MRM) mode. A mass spectrometry sensitizing reagent, 4′-carboxy-substituted rosamine (CSR) with high reaction activity and ionization efficiency was synthesized and firstly used as derivatization reagent. Parameters of dual-UADLLME, MAD and UHPLC-MS/MS conditions were all optimized in detail. Low toxic brominated solvents were used as extractant instead of traditional chlorinated solvents. Satisfactory linearity, recovery, repeatability, accuracy and precision, absence of matrix effect and extremely low limits of detection (LODs, 0.010 and 0.015 ng/mL for PPD and PPT, respectively) were achieved. The main advantages were rapid, sensitive and environmentally friendly, and exhibited high selectivity, accuracy and good matrix effect results. The proposed method was successfully applied to pharmacokinetics of PPD and PPT in rat plasma.

The article discusses hypoxic pathophysiology and high-altitude medicine as of December 2012, with a focus on the traditional Tibetan medicine Duoxuekang and its potential prevention of high-altitude polycythemia (HAPC) induced by hypoxia. Topics include the oxygen-carrying capacity of human blood, reduction of red blood cell and hemoglobin counts, and serum erythropoietin (EPO). Additional information is presented on high-performance liquid chromatography (HPLC) methods and hypoxia-inducible factor (HIF)-1.

AIM: Targeting the VEGF/VEGF receptor (VEGFR) pathway has proved to be an effective antiangiogenic approach for cancer treatment. Here, we identified 6-((2-((3-acetamidophenyl)amino)pyrimidin-4-yl)oxy)-N-phenyl-1-naphthamide (designated herein as DW10075) as a novel and highly selective inhibitor of VEGFRs. METHODS: In vitro tyrosine kinase activity was measured using ELISA, and intracellular signaling pathway proteins were detected by Western blot analysis. Endothelial cell proliferation was examined with CCK-8 assays, and tumor cell proliferation was determined with SRB assays. Cell migration, tube formation and rat aortic ring assays were used to detect antiangiogenic activity. Antitumor efficacy was further evaluated in U87-MG human glioblastoma xenograft tumors in nude mice receiving DW10075 (500 mg · kg(-1) · d(-1), po) for two weeks. RESULTS: Among a panel of 21 kinases tested, DW10075 selectively inhibited VEGFR-1, VEGFR-2 and VEGFR-3 (the IC50 values were 6.4, 0.69 and 5.5 nmol/L, respectively), but did not affect 18 other kinases including FGFR and PDGFR at 10 μmol/L. DW10075 significantly blocked VEGF-induced activation of VEGFR and its downstream signaling transduction in primary human umbilical vein endothelial cells (HUVECs), thus inhibited VEGF-induced HUVEC proliferation. DW10075 (1-100 nmol/L) dose-dependently inhibited VEGF-induced HUVEC migration and tube formation and suppressed angiogenesis in both the rat aortic ring model and the chicken chorioallantoic membrane model. Furthermore, DW10075 exhibited anti-proliferative activity against 22 different human cancer cell lines with IC50 values ranging from 2.2 μmol/L (for U87-MG human glioblastoma cells) to 22.2 μmol/L (for A375 melanoma cells). In U87-MG xenograft tumors in nude mice, oral administration of DW10075 significantly suppressed tumor growth, and reduced the expression of CD31 and Ki67 in the tumor tissues. CONCLUSION: DW10075 is a potent and highly selective inhibitor of VEGFR that deserves further development.

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