Effects of different ingredients of zedoary on gene expression of HSC-T6 cells

AIM： To investigate the effects of four different ingredients of zedoary （Curcuma aromatica oil, Curcumol, β-elemence, and Curcumin） on the gene expressions of hepatic stellate cells （HSCs）, and to explore the molecular mechanism of zedoary against hepatic fibrosis at gene network level. METHODS： We detected the mRNA sequences of 50 liver fibrosis-related genes in GenBank and designed oligonucleotide probes. We synthesized oligonucleotides with PE8909 DNA synthesizing instrument, and carried out oligonucleotide microarray with OGR-04 dropping instrument and aldehyded glass chip. Cultured HSC-T6 cells were breated wibh different concentrations of Colchicine, Curcuma aromatica oil, Curcumol, β-elemence, and Curcumin. According to the experiment of cell toxicity, we took the appropriate concentrations of medicines that resulted in over 50% of cell survival as experiment concentrations. We collected the cells at 1, 6, 12, and 24 h, and extracted total RNA with TRIzol reagent, then labeled cDNAs with Cy3-dUTP and Cy5-dUTP. These labeled cDNAs were hybridized to an oligonucleotide microarray which was washed several times and scanned by scanner GenePix 4000B. Different gene expressions of HSC-T6 cells were analyzed by ImaGene 4.2 software. RESULTS： After HSC-T6 cells were cultured in a medium containing 6.25μg/mL Colchicine for 12 h, expression of TIMP-1 decreased 2.2-folds. After HSC-T6 cells were cultured in a medium containing 78.125 μg/mL of Curcuma aromatica oil for 24 h, the expression of TIMP-2 and IL-6 decreased 2.3- and 2.2-folds, respectively. Moreover, after HSC-T6 cells were cultured in a medium containing 1.5625 μg/mL of Curcumol for 12 h, the expression of TGFμ1 and P450a decreased 2.3- and 2.1-folds, respectively. CONCLUSION： Our results may show the possible molecular mechanism of Curcuma aromatica oil and Curcumol against hepatic fibrosis.

Molecular mechanism of the qnrA genemediated quionlone resistance in Gram-negative bacteria

To explore the prevalence of the plasmid-mediated quinolone resistance gene qnrA in Gramnegative bacteria and to investigate its molecular genetic background and resistance profile in isolates harboring this gene, a total of 629 nalidixic acid-resistant isolates of non-repetitive Gram-negative bacteria were collected from clinical specimens between April 2004 and April 2006 and these isolates were screened for qnrA gene by PCR using specific primers combined with DNA sequencing. The extended spectrum β-1actamase （ESBL） or AmpC-producing isolates were distinguished by the phenotypic confirmatory test combined with DNA sequencing, and the antibiotics susceptibility test for qnrA-positive isolates was carried out by Kirby-Bauer and E-test method. To detect the location of the qnrA gene, plasmid conjugation and Southern hybridization were performed and the integron structure containing the qnrA gene was cloned by PCR strategy and sequenced by primer walking. It was demonstrated that the incidence of the qnrA-positive strains in nalidixic acid-resistant bacteria was 1.9% （12/629）, in which the detection rates for Klebiesiella pneumoniae. Enterobacter cloacae, Enterobacter aerogenes, Citrobacterfreundii and Salmonella choeraesuis were 2.2% （3/138）, 17. 1% （6/35）, 9. 1% （1/11）, 12.5% （1/8）, and 14.3% （1/7）, respectively. The qnrA gene was found to be embedded in the complex sull-type integron located on plasmids with varied size （80-180 kb）. Among them, 4 qnrA-positive isolates carried integron In37 and 8 isolates carried a novel integron, temporarily desig- nated as InX. All the qnrA-positive isolates were ESBL-producing and transferable for the multi-drug resistance. It is concluded that the plasmid-mediated drug-resistance mechanism exists in the quinolone resistant strains of isolates from hospitals in Guangdong area, but the incidence was rather low. Nevertheless, it is still possible that the horizontal transfer of the resistant qnrA gene might lead to the spreading of drug-resistance.