J AOAC Int. 2009 Mar-Apr; 92(2): 663-71Qiao YL, Sheng YX, Wang LQ, Zhang JLA sensitive and specific method using rapid resolution liquid chromatography coupled with UV-Vis detection was developed for fingerprint analysis of Rhizoma coptidis and simultaneous determination of 4 alkaloids: jatrorrhizine, coptisine, palmatine, and berberine. Samples of R. coptidis grown under different cultivation conditions and from different habitats were analyzed. The analysis was performed using a reversed-phase octylsilyl (C8) column and gradient elution. The mobile phase consisted of acetonitrile and 20 mmol/L KH2PO4. Each analysis was completed within 3.5 min. The method showed good linearity within test ranges of 4.75-47.50 microg/mL for jatrorrhizine, 20.60-164.80 microg/mL for coptisine, 18.07-180.73 microg/mL for palmatine, and 89.70-717.57 microg/mL for berberine. The method showed good precision, repeatability, and stability for quantification of the 4 alkaloids. The lower limit of detection was 0.19 ng for jatrorrhizine, 0.21 ng for coptisine, 0.15 ng for palmatine, and 0.14 ng for berberine. The lower limit of quantification was 0.57 ng for jatrorrhizine, 0.82 ng for coptisine, 0.55 ng for palmatine, and 0.27 ng for berberine. The overall recovery ranged from 96.30 to 104.10% for the 4 alkaloids. The method is accurate, rapid, and convenient, and it is suitable for routine quality control of R. coptidis.

Chem Pharm Bull (Tokyo). 2009 Jun; 57(6): 625-7Wang G, Liu JS, Lin BB, Wang GK, Liu JKTwo new furanoid norditerpenes (1, 2) were isolated from the root tubers of Dioscorea bulbifera L. Their structures were established on the basis of extensive spectroscopic analysis.

Chem Pharm Bull (Tokyo). 2009 Jun; 57(6): 600-2Luo XM, Qi SH, Yin H, Gao CH, Zhang STwo new quinoldione alkaloids, methyl 2-(3-hydroxy-1-methyl-2,4-dioxo-1,2,3,4-tetrahydroquinolin-3-yl)acetate (1) and 3-hydroxy-1-methyl-3-(2-oxopropyl)quinoline-2,4(1H,3H)-dione (2), and two quinolinone alkaloids previously synthesized but first isolated as natural products, N-methylflindersine (3) and 4-hydroxy-3-methoxy-1-methyl-2(1H)-quinolinone (4), were isolated from the stem bark of Micromelum falcatum, together with the known N-methylswietenidine-B (5). Their structures were established mainly on the basis of 1D- and 2D-NMR techniques. All compounds were evaluated for toxicity towards brine shrimp larvae, and 3 showed strong toxicity with an LD(50) value of 1.39 mug/ml.

Acta Pharmacol Sin. 2009 Jun 1; Qian J, Zhu CH, Tang S, Shen AJ, Ai J, Li J, Geng MY, Ding JAim:We aimed to investigate the potential modification of previously unrecognized surface glycoprotein(s) by alpha2,6-sialylation other than by integrins.Methods:The expression of beta-galactoside alpha2,6-sialyltransferase (ST6Gal-I) in the colon cancer cell line HCT116 was reduced by siRNA. The adhesion and Boyden chamber assay were used to detect the variation in cell motility. alpha2,6-Sialylation proteins were detected with lectin affinity assay. The mRNA expression, protein expression and downstream signaling modulation with siRNA were detected using reverse transcription-polymerase chain reaction, flow cytometry analysis, and Western blot.Results:In HCT116 cells, the knockdown of ST6Gal-I inhibited cell motility, but did not affect cell adhesion. This selectively altered cell migration was caused by the loss of alpha2,6-sialic acid structures on c-Met. Moreover, STAT3 was dephosphorylated at tyrosine 705 in ST6Gal-I-knockdown (ST6Gal-I-KD) HCT116 cells.Conclusion:c-Met is the substrate of ST6Gal-I. The hyposialylation of c-Met can abolish cell motility in ST6Gal-I-KD HCT116 cells.Acta Pharmacologica Sinica advance online publication, 1 June 2009; doi: 10.1038/aps.2009.84.