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.

SUMMARYThe relationship between mycoplasma and ureaplasma infection and male infertility has been studied widely; however, results remain controversial. This meta-analysis investigated the association between genital ureaplasmas (Ureaplasma urealyticum, Ureaplasma parvum) and mycoplasmas (Mycoplasma hominis, Mycoplasma genitalium), and risk of male infertility. Differences in prevalence of ureaplasma and mycoplasma infection between China and the rest of the world were also compared. Study data were collected from PubMed, Embase and the China National Knowledge Infrastructure. Summary odds ratio (OR) with 95% confidence interval (CI) was applied to assess the relationship. Heterogeneity testing and publication bias testing were also performed. A total of 14 studies were used: five case-control studies with 611 infertile cases and 506 controls featuring U. urealyticum infection, and nine case-control studies with 2410 cases and 1223 controls concerning M. hominis infection. Two other infection (U. parvum and M. genitalium) were featured in five and three studies, respectively. The meta-analysis results indicated that U. parvum and M. genitalium are not associated with male infertility. However, a significant relationship existed between U. urealyticum and M. hominis and male infertility. Comparing the global average with China, a significantly higher positive rate of U. urealyticum, but a significantly lower positive rate of M. hominis, was observed in both the infertile and control groups in China.

The bryostatins, powerful protein kinase C (PKC) agonists, are a family of complex macrolactone natural products. They are originally isolated from the marine bryozoan Bugula neritina. So far tweenty bryostatins have been obtained naturally and exhibit a remarkable range of biological activities, including antineoplastic activity, synergistic chemotheoreputic activity, cognition and memory enhancement, etc. Of the 20 known members, the most extensively studied is bryostatin 1. The effects of bryostatin 1 are mainly linked to its ability of selectively modulating the function of various individual protein kinase C (PKC) isozymes. Moreover, bryostatin 1, or in combination with other agents, has been proposed for phase I and phase II clinical trials. The bryostatins have excellent biological properties, but are scarce in nature. Therefore, it has attracted considerable interests in structural modification over the past two decades. In this review, we will attempt to summarize the main developments that have occurred in the structure-activity relationship and biology of bryostatins over the period 1982-2011.

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In this paper we report, to the best of our knowledge, the first experimental realization of distributed feedback (DFB) semiconductor lasers based on reconstruction-equivalent-chirp (REC) technology. Lasers with different lasing wavelengths are achieved simultaneously on one chip, which shows a potential for the REC technology in combination with the photonic integrated circuits (PIC) technology to be a possible method for monolithic integration, in that its fabrication is as powerful as electron beam technology and the cost and time-consuming are almost the same as standard holographic technology.

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