A new caffeic acid tetramer from the Dracocephalum moldavica L.

A new caffeic acid tetramer compound, named (+) methyl rabdosiin (4), together with seven known caffeic acid multimers (1-3, 5-8) and one caffeic acid monomer (9), were isolated from the aerial parts of Dracocephalum moldavica L. The structures of these compounds were assigned on the basis of 1D and 2D NMR spectroscopic and mass spectrometry analyses. The protective effects of compounds 2-4 against hydrogen peroxide (H2O2)-induced apoptosis were evaluated in primary cardiomyocytes of SD neonatal rats in vitro by the MTT method. Three compounds exhibited potent protective activities at 12.5 µg/mL.

Clinicopathological and molecular characteristics of synchronous gastric adenocarcinoma and gastrointestinal stromal tumors.

Synchronous gastric tumors that consist of both gastrointestinal stromal tumor (GIST) and adenocarcinoma are rare. We studied the clinicopathological and molecular characteristics of six cases containing both gastric adenocarcinoma and GIST. By means of immunohistochemical analysis, all GIST cells expressed CD117, CD34 and Dog1 in all six synchronous gastric adenocarcinomas with GIST, and in GIST alone. Sequencing analysis demonstrated that exon 11 c-kit mutations were present in two of six synchronous tumors and four of five GISTs. One of the two exon 11 c-kit mutations in synchronous adenocarcinomas with GISTs was an uncommon mutation of CTT > CCA at amino acid 576, and the other was a GTT deletion at amino acid 560. The mutation was a homozygous A > G mutation in exon 12 (amino acid 567) of PDGFR-α. We concluded that the exon 11 mutations were the most important in both cases of synchronous gastric adenocarcinoma with GIST and GIST alone. The mutation rate was higher in GIST alone than in synchronous adenocarcinoma with GIST.

Expression of miR-10b gene and methylation level in schwannomas / 西安交通大学学报(医学版)

Objective To analyze miR-10b expression level and the gene upstream methylation level in schwannomas so as to explore and identify the potential target genes for miR-10b in schwannomas .Methods The miR-10b with its potential target genes including HOXB 3 ,HOXD10 ,PTEN ,PIK3CA ,MAPRE1 and HADC4 were quantitatively analyzed by PCR in 13 cases of schwannomas and 6 cases of human vestibulocochlear nerves . We studied the correlation between the differentially expressed genes and the clinical characteristics of schwannomas . Finally ,the differences in miR-10b gene upstream methylation levels were measured and analyzed by pyrosequencing between schwannomas and normal vestibulocochlear nerves .Results Compared with that of normal nerves ,the expression level of miR-10b was significantly higher (P=0 .0003) while the level of PTEN was lower (P=0 .0047) in schwannomas .Negative correlation existed between the levels of miR-10b and PTEN (P=0 .001 , r= -0 .689) . Moreover ,the methylation level of the miR-10b gene promoter was downregulated in schwannomas ;it had negative correlation with the expression level of miR-10b (P= 0 .011 , r= -0 .571) .There was a significant difference in tumor mass diameter between miR-10b higher expression group and lower group (P=0 .016);however ,there was no difference in age or recurrence rate (P>0 .05) .Conclusion The downregulation of methylation level of the promoter leads to higher expression of miR-10b gene ,and it may targetedly inhibit the expression of PTEN .