Inhibition of Aspergillus parasiticus and Cancer Cells by Marine Actinomycete Strains

Ten actinomycete strains isolated from the Yellow Sea off China＇s coasts were identified as belonging to two genera by 16S rDNA phylogenetic analysis： Streptomyces and Nocardiopsis. Six Streptomyces strains （MA10, 2SHXF01-3, MA35, MA05-2, MA05-2-1 and MA08-1） and one Nocardiopsis strain （MA03） were predicted to have the potential to produce aromatic polyketides based on the analysis of the KSa （ketoacyl-synthase） gene in the type II PKS （polyketides synthase） gene cluster. Four strains （MA03, MA01, MA10 and MA05-2） exhibited significant inhibitory effects on mycelia growth （inhibition rate 〉50%） and subsequent aria- toxin production （inhibition rate 〉75%） of the mutant aflatoxigenic Aspergillus parasiticus NFRI-95. The ethyl acetate extracts of the broth of these four strains displayed significant inhibitory effects on mycelia growth, and the IC50 values were calculated （MA03： 0.275 mg mL-1, MA01：0.106 mg mL-1, MA10：1.345 mg mL-1 and MA05-2：1.362 mg mL-1）. Five strains （2SHXF01-3, MA03, MA05-2, MA01 and MA08-1） were selected based on their high cytotoxic activities. The ethyl acetate extract of the Nocardiopsis strain MA03 was particularly noted for its high antitumor activity against human carcinomas of the cervix （HeLa）, lung （A549）, kidney （Caki-1） and liver （HepG2） （IC50： 2.890, 1.981, 3.032 and 2.603 μgmL-1, respectively）. The extract also remarkably inhibited colony formation of HeLa cells at an extremely low concentration （0.5μgmL 1）. This study highlights that marine-derived actinomycetes are a huge resource of compounds for the biological control of aflatoxin contamination and the development of novel drugs for human carcinomas.

Reflections on Cultural Cultivation in Piano Education

Piano is one of the more important branches of the music education system,which carries an extremely rich cultural heritage,and it has received more attention and preference in modern education.Piano education needs to go through a systematic process,taking into account both theory and practice.However,it is clear from the current situation of piano education in China that it has not reached the ideal state,and there are even inappropriate factors in the fundamental concept of education.

SHORT COMMUNICATIONS Comparison of inositol phosphates formation and gene expression of Gq alpha subunit in cultured aortic smooth muscle cells from spontaneously hypertensive and Wistar Kyoto rats

Abstract Objecitve To explore whether phosphoinositide specific phospholipase C (PLC) activation via G protein in vascular smooth muscle cells (VSMCs) is altered in spontaneously hypertensive rats (SHR). Methods The VSMCs derived from aortae of SHR and Wistar Kyoto (WKY) rats were loaded for 48 hours with myo inositol. Inositol phosphate release was initiated by the addition of 10 5 mol/L norepinephrine in intact cells or by guanosine 5' 0 (3 thio tri sphosphate) (GTP gamma S) in permeabilized cells. In the meantime, growth arrested VSMCs were stimulated by 10% calf serum for 0, 30, 45, or 60 min, then gene expressions of Gq alpha subunit (G alph a q) were observed. Results There were no significant differences in inositol 1, 4,5 triphosphate (IP 3) level and expression of G alpha q mRNA between quiescent VSMCs from SHR and that from WKY. When stimulated by norepinephrine, IP 3 production increased transiently with a peak level at 10 s in VSMCs from WKY, and a rapid biphasic IP 3 response, which was significantly higher than that of WKY, in VSMCs from SHR had been observed. G proteins activated by GTP gamma S significantly raised IP 3 production in VSMCs from SHR compared to WKY (SHR vs WKY: 234.8%±29.2% vs 142.4%±12.0% of basal IP 3, P<0.05). In addition, the serum effect showed an significant increase in expression of G alpha q mRNA in VSMCs from SHR. Conclusions The hereditary factors are not the only variable regulating IP 3 metabolism and G alpha q gene expression. Influences of multi environmental factors such as vasoactive compounds, together with genetic predisposition, palys an important role in the highly sensitive response of IP 3 production and G alpha q gene over expression in SHR.