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Resistance to apoptosis is a characteristic of cancer. Curcumin has become a potential anticancer drug for its pro-apoptotic effects, but the underlying mechanisms remain unclear. Furthermore, the Notch3-p53 signaling axis serves an important role in cell fate. The present study was designed to investigate the antitumor effect of curcumin by the Notch3-p53 axis in mouse myeloma P3X63Ag8 cells. The effects of curcumin on the viability of P3X63Ag8 cells were evaluated using an MTT assay. Quantitative expression of the Notch3-p53 signaling axis-associated genes was measured by reverse transcription-quantitative polymerase chain reaction, and western blot analysis was used to investigate the expression of proteins. Additionally, flow cytometry was used to measure the ratio of apoptosis. The results demonstrated that curcumin could significantly inhibit cell viability. No significant pro-apoptotic effect was observed when the concentration of curcumin was

A new series of Mannich base of 1,3,4-oxadiazole derivatives possessing 1,4-benzodioxan (6a-6ae) were synthesized and characterized by (1)H NMR, ESI-MS and elemental analysis. The structure of 6b was further confirmed by single crystal X-ray diffraction. All these novel compounds were screened for their in vitro antioxidant activity employing 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH), 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonate) cationic radical (ABTS(+)) and ferric reducing antioxidant power (FRAP) scavenging assays. Due to the combination of 1,4-benzodioxan, 1,3,4-oxadiazoles and substituted phenyl ring, most of them exhibited nice antioxidant activities. In all of these three assays mentioned above, compounds 6f and 6e showed significant radical scavenging ability comparable to the commonly used antioxidants, BHT and Trolox. Seven compounds with representative substituents or activities were selected for further assays in chemical simulation biological systems-inhibition of microsomal lipid peroxidation (LPO) and protection against 2,2'-azobis (2-amidinopropane hydrochloride) (AAPH) induced DNA strand breakage, in which, 6f and 6e were demonstrated to be of the most potent antioxidant activities.

1,2-Benzenedicarboxaldehyde-3,4,5-trihydroxy-6-methyl (flavipin) was found to be antagonistic against nematodes and fungi. Here we demonstrated that flavipin is a potent antioxidant in vitro and in vivo, which has great potential in the therapy for free radical-associated diseases. Therefore, flavipin-producing bio-source was screened from 80 endophytes in Ginkgo biloba. Seven endophytic fungi were able to synthesize antioxidant substances and identified by ITS rDNA sequences. Among them, Chaetomium globosum CDW7 was a remarkable producer of flavipin. The fermentation parameters of CDW7 were then optimized for high flavipin production. Cultured under the optimal condition (25 °C, 100/250 mL flask, 12 discs/flask, 150 rpm, pH 6.5) for 14 days, CDW7 was able to synthesize flavipin at a production of 315.5 mg/L. In addition, flavipin output was positively correlated to antioxidant activities of crude extracts with a correlation coefficient of 0.8235, indicating that flavipin was the major antioxidant component of CDW7's metabolites. These data demonstrated that CDW7 was a highly yielded bio-source of antioxidant flavipin.

Streptococcus suis is an important swine and human pathogen, and it has presented a considerable challenge to the global public health community. Dominguez-Punaro et al. (2007) showed that two strains of mice were differentially susceptible to S. suis. The attainment of information on the differential expression of host response genes following S. suis infection is relevant to the understanding of the molecular mechanism of this disease. The intent of this study was to select and isolate differentially expressed genes from A/J and C57BL/6 mice that are associated with the host response to S. suis infection. These baseline data will allow for the screening and cloning of specific resistance genes, and further our understanding of the molecular mechanism of S. suis infection. Eight-week-old C57BL/6 and A/J mouse were infected with S. suis serotype 2, a 200-μL volume of a bacterial suspension (1 × 108 CFU/mL) was administrated by intraperitoneal injection to the mice, and cDNA subtraction libraries were constructed by suppression subtraction hybridization (SSH). Genes involved in immune function, such as lysozyme, interferon-active protein, macrophage activation 2-like protein, complement component-3 and Ly108 protein were up-regulated in the spleen of C57BL/6 mice to a greater extent than they were in the spleen of A/J mice, subsequent to infection with S. suis serotype 2. Interestingly, we observed that several splenic signaling factors associated with phospholipid metabolism were up-regulated to a greater extent as well in C57BL/6 mice than they were in A/J mice following infection with S. suis serotype 2. These data suggest that phospholipid metabolism may be involved in the host defense response to S. suis invasion, thereby contributing to the organism’s overall immune response to this pathogen. Key words: Streptococcus suis serotype 2, suppression, subtractive hybridization, differentially expressed genes, mouse spleen.