Induction of Antiphytopathogenic Metabolite and Squalene Production and Phytotoxin Elimination by Adjustment of the Mode of Fermentation in Cocultures of Phytopathogenic Nigrospora oryzae and Irpex lacteus.

The investigation of the metabolites from different cocultures of Nigrospora oryzae and Irpex lacteus in solid medium revealed two new squalenes (1 and 2); one new azaphilone (3); two new tremulane sesquiterpenes (4 and 5); and three known compounds, conocenol B (6), conocenol C (7), and 4-(4-dihydroxymethylphenoxy)benzaldehyde (8). The antagonistic relationship was examined by studying metabolite production. The production of compounds 6 and 8 by I. lacteus after the induction of coculture indicated significant selectivity for antifungal activity against phytopathogenic N. oryzae, with MICs of 16 µg/mL; compounds 6 and 8 also exhibited antifungal activities in vivo against Cerasus cerasoides infected by N. oryzae at concentrations of 100 µg/mL. New compounds 2 and 4 showed antifungal activities against Colletotrichum gloeosporioides, with MICs of 8 µg/mL, and compound 4 showed antifungal activity against Didymella glomerata with an MIC of 1 µg/mL. These results indicate that the mutually antagonistic relationship in the coculture of the phytopathogen and the endophyte can result in antibiotics that inhibit the phytopathogen and downregulate the production of phytotoxins by phytopathogenic N. oryzae. New compound 5 from I. lacteus showed weak activity against acetylcholinesterase (AChE), with an inhibition ratio of 16% at a concentration of 50 µM.

[Overexpression of miR-30a Promotes Apoptosis of Leukemia K562 Cells].

OBJECTIVE: To investigate the pro-apoptotic effect and mechanism of miR-30a overexpression on chronic myeloid leukemia K562 cells. METHODS: The k562 cells were transfected with the recombinant plasmid pEGFP-pre-miR-30a, the real-time quantitative PCR was used to detect the level of miR-30a and BCR/ABL, and then the cell apoptosis was assessed by flow cytometry with AnnexinV-FITC/PI double staining. Western blot was used to detect the expression of BCR/ABL protein,apoptosis-related protein BCL-2 and BAX, PTEN, AKT and p-AKT. RESULTS: Sequencing and digestion map indicated that the recombinant plasmid was constructed successfully. Compared with 2 control groups, the miR-30a expression in k562 cells transfected with recombinant plasmid pEGFP-pre-miR-30a was obviously up-regulated. The expression of BCR/ABL mRNA and BCR/ABL protein was both significantly down-regulated. Apoptotic rate was significantly enhanced (both P<0.05),and the expression of anti-apoptotic protein BCL-2 was down-regulated while the expression of pro-apoptotic protein BAX was up-regulated. The level of PTEN was significantly up-regulated in omparison with control groups,no variation was found in total AKT, but the expression of p-AKT was down-regulated. CONCLUSION: The overexpression of miR-30a is abled to down-regulate the level of BCR/ABL mRNA and BCR/ABL protein, and increase apoptotic rate, its mechanism may be related with inhibition of the activity of BCR/ABL-PTEN/AKT signaling pathway.

The role of medical gas in stroke: an updated review.

Medical gas is a large class of bioactive gases used in clinical medicine and basic scientific research. At present, the role of medical gas in neuroprotection has received growing attention. Stroke is a leading cause of death and disability in adults worldwide, but current treatment is still very limited. The common pathological changes of these two types of stroke may include excitotoxicity, free radical release, inflammation, cell death, mitochondrial disorder, and blood-brain barrier disruption. In this review, we will discuss the pathological mechanisms of stroke and the role of two medical gases (hydrogen and hydrogen sulfide) in stroke, which may potentially provide a new insight into the treatment of stroke.