Portulaca oleracea L. is a traditional edible and medicinal plant in China. Flavonoids are one of the main active ingredients of this plant. Five extraction technologies of flavonoids from P. oleracea L. were investigated and compared, including microwave-assisted extraction, ultrasonic extraction, reflux extraction, Soxhlet extraction, and marinated extraction. The results showed that microwaveassisted extraction was most suitable for the extraction of flavonoids from P. oleracea L. because of its high effect and short extraction time. The found optimum extraction conditions were that the ethanol concentration was 70% (v/v), solid-liquid ratio was 1:50, extracting temperature was 50°C and irradiation time was 9 min. Quantification was performed by means of UV-Vis spectrophotometry with chromogenic system of NaNO 2 -Al (NO 3 ) 3 -NaOH. Under the optimum conditions, the calibration curve for the analyte was linear with the correlation coefficients greater than 0.9999. The average recovery was 102.6%, and its RSD was 1.13%(n=5). Eight types of P. oleracea L. according to different habits were investigated. The total content of flavonoids was 7. 16, 7.10, 9.38, 6.82, 6.78, 11.36, 5.12, and 1.76 mg g −1 , respectively.

Aims:  To compare bacterial populations and antimicrobial resistance patterns between clinical and sewage isolates from a regional hospital in northern Taiwan. The dissemination of antibiotic‐resistant bacteria from hospital compartments to the hospital sewage treatment plant was examined. Methods and Results:  A total of 1020 clinical isolates and 435 sewage isolates were collected between July and September 2005. The percentages of Gram‐negative bacteria from the clinical and sewage isolates were 87·2% and 91·0%, respectively (P = 0·033). Escherichia coli were the leading bacterial isolates in both groups. Antimicrobial susceptibility testing showed a significant difference (P < 0·001) in resistance to ampicillin (85·6%vs 94·1%), ampicillin/sulbactam (31·7%vs 55·4%), cefazolin (29·2%vs 71·5%) and cefuroxime (20·7%vs 61·9%) between clinical and sewage coliform isolates, respectively. Conclusions:  The sewage isolates had higher antimicrobial resistance rates than the clinical isolates from the same hospital. Significance and Impact of the Study:  The low efficacy of the hospital sewage treatment may contribute to the dissemination of multidrug resistant bacteria from this hospital compartments to the environment. Practices which limit the disposal of antimicrobial agents into the wastewater system may be the possible measure to prevent the selection of multidrug‐resistant bacteria from sewage treatment plants.

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In the present study, we have tested the hypothesis that fusion between an altered cell and a mesenchymal stem cell produces a hybrid cell with enhanced characteristics associated with metastatic cancer cells, and we have developed a flexible model for investigating the mechanisms of metastasis. Human HepG2 cells with low metastatic potential were induced to fuse with rat bone marrow mesenchymal stem cells, and the progeny were compared with the parental cells for possession of enhanced in vitro and in vivo characteristics of malignant cells. Compared to the parental cells, the fused cells exhibited enhanced expression of E-cadherin, vimentin, Twist, Snail, matrix metalloproteinase 2 and 9 activities, aneuploidy and enhanced in vitro invasion and migration. In an in vivo xenograft assay, the fused cells generated increased numbers of metastatic liver and lung lesions. This model system is a flexible tool for investigation of the mechanisms of stem cell fusion in carcinogenesis and metastasis and for the discovery of new therapeutic targets to inhibit metastasis.

Lead is a ubiquitous environmental and industrial pollutant that may have toxic effects on the male. Vitamins may protect against toxic effects of lead in the liver and reproductive system, which is confirmed by our initial research. The aim of this study was to further investigate the protective effects of vitamins (ascorbic acid combined with thiamine) on lead acetate (Pb)-induced reproductive toxicities in mice and study the possible mechanisms underlying these effects. Forty-five male mice were randomly divided into 3 groups, 15 mice in each and received daily intragastric administration with control, Pb (20 mg/kg), and Pb+vitamins (ascorbic acid of 420 mg/kg+thiamine of 30 mg/kg) for 6 weeks, respectively. The Pb-treated animals showed significant decreases in the epididymal sperm count and motility compared to the control group, while the Pb+vitamins group had significant increases for these variables. Moreover, an increasing apoptosis of germinal cells induced by Pb was reduced by vitamin treatment. Pb induced the activation of Caspase-3, Fas/Fas-L and Bcl-2 with elevated levels, and the adaptor protein primarily regulated signaling through Fas and required for Fas-induced apoptosis. In conclusion, ascorbic acid combined with thiamine exhibited protective effect on reproductive system by inhibiting Pb-induced excessive cell apoptosis.