The leaves of Apocynum venetum L. are used as a tea material in north China and Japan. A water extract (500 mg/kg/day, one week administration) of the leaves of A. venetum showed protective effects against carbon tetrachloride (CCl₄, 30 μl/mouse) or D-galactosamine (D-GalN, 700 mg/kg)/lipopolysaccharide (LPS, 20 μg/kg)-induced liver injury in mice. Tumor necrosis factor-α (TNF-α) secreted from LPS-stimulated macrophages is the most crucial mediator in the D-GalN/LPS-induced liver injury model. The extract had no significant inhibition on the increase of serum TNF-α (1169 } 132 pg/ml vs. 1595 } 314 pg/ml of control), but exhibited a complete inhibition at the concentration of 100 μg/ml on TNF-α (100 ng/ml)-induced cell death in D-GalN (0.5 mM)-sensitized mouse hepatocytes. Further activity-guided fractionation resulted in the isolation of fifteen flavonoids viz. (−)-epicatechin (1), (−)-epigallocatechin (2), isoquercetin (3), hyperin (4), (+)-catechin (5), (+)-gallocatechin (6), kaempferol-6 Œ-O-acetate (7), isoquercetin-6 Œ-O-acetate (8), catechin-[8,7-e]-4α-(3,4-dihydroxpyhenyl)-dihydro-2(3H)-pyranone (9), apocynin B (10), apocynin A (11), cinchonain Ia (12), apocynin C (13), apocynin D (14) and quercetin (15). All the compounds showed inhibitory effects on TNF-α-induced cell death with different intensities. The flavonol glycosides 3, 4, 7 and 8 and the phenylpropanoid-substituted flavan-3-ols 11 and 12 showed potent inhibitory effects on TNF-α-induced cell death with IC₅₀ values of 37.5, 14.5, 31.2, 55.1, 71.9 and 41.2 μM, respectively. In contrast, the clinically used 5 and its analogues 1, 2 and 6 showed apparent activity only at 80 μM. These flavonoids appeared to be the hepatoprotective principles of the leaves of A. venetum. The hepatoprotective effects exhibited by the extract and its constituents suggest a validation of the leaves as a tea material. Av:water extract of the leaves of Apocynum venetum CCl₄:carbon tetrachloride D-GalN:D-galactosamine LPS:lipopolysaccharide TNF-α:tumor necrosis factor-α ALT:alanine aminotransferase MTT:3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide ROIs:reactive oxygen species

Objective: For evaluating the antibiotic resistance ofHelicobacter pylori, the agar dilution method is the gold standard; however, using this method in daily practice is laborious. E-test has been proposed to be an uncomplicated method. This study was aimed at validating the E-test and detecting the presence of any bias between the agar dilution method and E-test.Results: The agar dilution method and E-test were performed using five antibiotics for 72 strains ofH. pyloriobtained from clinical patients in Indonesia. The E-test’s results showed a higher prevalence of resistance to all the antibiotics tested but the difference was not significant. Results showed high essential agreement (> 90.0%) for all the antibiotics, but only 84.7% for metronidazole. The agreement for MIC value was acceptable for levofloxacin, clarithromycin, and metronidazole. For amoxicillin, it showed only fair agreement (0.25) by the Kappa analysis and significant difference by Passing-Bablok regression. Even though some discrepancies were found, the E-test has an acceptable agreement for levofloxacin, metronidazole, tetracycline, and clarithromycin but further confirmation may be necessary for amoxicillin.