Neo-tanshinlactone (1) was isolated and synthesized for the first time and evaluated in vitro against several human cancer cell lines. Compound 1 showed significant inhibition against two ER+ human breast cancer cell lines and was 10-fold more potent and 20-fold more selective as compared to tamoxifen citrate. Compound 1 also potently inhibited an ER-, HER-2 overexpressing breast cancer cell line. Therefore, this novel compound merits further development as an anti-breast cancer drug candidate.

Plumbagin is found in many medicinal plants and has been reported to have antimicrobial activities. We examined the molecular responses of Escherichia coli to plumbagin by using a proteomic approach to search for bacterial genes up-regulated by the drug. The protein profile obtained was compared with that of E. coli without the plumbagin treatment. Subsequent analyses of the induced proteins by mass spectroscopy identified several up-regulated genes, including ygfZ, whose function has not been defined. Analyses of the 5-flanking sequences indicate that most of these genes contain a marbox-like stretch, and several of them are categorized as members of the mar/sox regulon. Representatives of these genes were cloned into plasmids, and the marbox-like sequences were modified by site-directed mutagenesis. It was proven that mutations in these regions substantially repressed the level of proteins encoded by the downstream genes. Furthermore, plumbagin's early effect was demonstrated to robustly induce SoxS rather than MarA, an observation distinctly different from that seen with sodium salicylate.Plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone) is a naphthoquinone having antibacterial (6), antifungal (5), anticancer (22), and antimutagenic activities (7). Like other redoxcycling chemicals such as paraquat and menadione, plumbagin has been used as an agent to generate superoxide or reactive oxygen species in order to study oxidative stress (14). Plumbagin has been suggested to activate SoxS by oxidizing the SoxR molecule (10, 21) or inhibiting the repression of MarR (2), the effect of which is exerted on marA, resulting in activation of the mar/sox regulon. In addition, it has been observed that the expression of some members of the mar/sox regulon in Escherichia coli, such as sodA (8), nfo (3), ribA (20), and pqi (21), is up-regulated by treatment with plumbagin.Although plumbagin could induce excessive expression of superoxide dismutase and catalase, overexpression of sodA failed to protect E. coli (17). The toxic effect of plumbagin may not simply result from the production of reactive oxygen species. It has been reported that plumbagin inhibits NADH dehydrogenase, as well as causing respiratory arrest (17). Plumbagin has also been shown to modify the lactose carrier and inhibit its binding with galactoside; the modified carrier then becomes completely inactive (29). The above effects appeared more or less to result directly from the chemical nature of plumbagin. In this report, we focus on the responses of the bacteria to the chemical, in which multiple proteins were simultaneously induced by plumbagin treatment. We report the evaluation of the bacterial regulatory systems after treating E. coli with plumbagin. MATERIALS AND METHODSBacterial strains, plasmids, and growth conditions. E. coli JM109 was used as the major experimental strain for the chemical treatments and the cloning host. Plasmids pGEM-T-easy (Promega, Madison, WI), pBluescript II SKϩ (Stratagene, La Jolla, CA), and pQE60 (QIAGEN, Valencia, CA) wer...

The novel pyrazines, (E)- and (Z)-5-methyl-3-(2-methylbutyl)-2-(3-methylbut-1-enyl)pyrazine, (E)- and (Z)-5-methyl-3-isopentyl-2-(3-methylbut-1-enyl) pyrazine, (E)- and (Z)-5-methyl-3-(2-methylbutyl)-2-(3-methylpent-1-enyl)pyrazine, (E)- and (Z)-5-methyl-3-isopentyl-2-(3-methylpentl-enyl) pyrazine, together with the known pyrazines, 2,5-dimethyl-3-(2-methylbutyl)pyrazine and 2,5-dimethyl-3-isopentylpyrazine, have been identified from the head of the Australian ponerine antRhytidoponera metallica. Alkanes and alkenes, in small amounts, were also detected.

In this paper, the real-time defects inspection was implemented via use of paralleled structure and high-speed operation of FPGA. The hardware circuit based on FPGA was established. According to signal characteristics of polymeric film defects, the preprocessing scheme of defect images based on FPGA was designed. The defect data were packed according to the defined format. Data processed were transferred to PC through USB2.0 real-timely to reconstruct defect microscopic images. The quantity of transferred data was decreased tremendously by this method. The inspecting speed was greatly improved.

Uniaxial creep tests on micro-regions of P92 steel base metal and welding HAZ specimens were carried out at 923 K and under different stress levels. The creep equation of index of B and n was obtained from the test data fitted by using least square method. Then, creep crack growth tests based on the reference stress method on P92 steel base metal and welding HAZ compact tensile samples were carried out at 923 K and under stress intensity factor K of 18 MPa·m1/2. From the calculated and experimental data, it was found that a good relationship existed between the creep crack growth rate da/dc and high temperature creep fracture parameter C*. The reference stress method was verified to calculate the C* of compact tension specimens and can predict the creep crack growth rate of the P92 steel base metal and welding HAZ materials under steady state creep conditions. At the same time, high temperature defect evaluation parameters of D0 and Φ were obtained by fitting the linear parts in the relation curves using the log-log method. This study provides tests data on the defects evaluation and life prediction of P92 steel welding materials.

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