Detection of cytokeratin20 mRNA in peripheral blood from colonic cancer patients by fluorescence quantitative polymerase chain reaction / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the expression level of cytokeratin20 mRNA (CK20 mRNA) of cancer cells in peripheral blood from colorectal cancer patients, detected by fluorescence quantitative polymerase chain reaction (FQ-PCR), and to evaluate its clinical value.</p><p><b>METHODS</b>To systemically study the reproducibility, quantitative range and amplification efficiency of CK20 mRNA detection by FQ-PCR, analyze and compare the result consistency with conventional RT-PCR and immunohistochemistry, separately. The expression level of CK20 mRNA of cancer cells in peripheral blood was examined in 136 colorectal cancer cases with or without hepatic metastasis.</p><p><b>RESULTS</b>The within-run and between-run CV of FQ-PCR to assay CK20 mRNA were 3.6% and 5.3%, respectively, quantitative range was from 10(3) copies/ml to 10(8) copies/ml and amplification efficiency was 87.4%. Comparing with traditional RT-PCR and immunohistochemistry, the Kappa value was 0.87 and 0.83, respectively. The expression level of CK20 mRNA of cancer cells in peripheral blood from colorectal cancer patients was (3.52 +/- 1.47) x 10(4) copies/ml, and the expression positive rate was 48.5%. None was found among the 75 cases in the control group. The positive rate of CK20 mRNA of cancer cells in peripheral blood was 9.5%, 25.0%, 48.8% and 87.5% in the patients at Dukes stage A, B, C and D, respectively (P < 0.05). The positive rate of CK20 mRNA was 87.5% in patients with hepatic metastasis and 32.3% in patients without hepatic metastasis (P < 0.05). CK20 mRNA showed a tendency to decline in 35 cases of colorectal cancer within the 1st, 3rd and 5th week after operation. There was no difference among the data of pre-operation cases and on the 1st, 3rd week (P > 0.05), but a significant difference between pre-operation and the 5th week (P < 0.05).</p><p><b>CONCLUSION</b>FQ-PCR is a rapid and sensitive method for quantitating CK20 mRNA. The expression of CK20 mRNA of cancer cells in peripheral blood from colorectal cancer patients has a correlation with recurrence and metastasis of the tumors. Detection of CK20 mRNA is helpful to monitor hematogenous dissemination of colorectal cancers.</p>

Study on Flavonoids Producing and Kinetics in Cell Suspension Culture of Eucommia ulmoides Oliv / 中国生物工程杂志

The type of basic media and the contents of plant growth substances were investigated by orthogonal design experiment,and also the effects of different culture conditions on the growth of suspension cells and the accumulation of total flavonoids in Eucommia ulmoides were studied.The results showed that B5 medium supplemented with 0.5mg/L NAA,0.6mg/L 6-BA and 30g/L sucrose,at initial pH 5.0～5.5,20g(FW)/L inoculation quantity and 110 r/min of rotation speed was a preferable culture conditions for E.ulmoides suspension cells growth and flavonoids synthesis.The results of metabolic kinetics analysis for E.ulmoides cell suspension culture showed that the logistic and Luedeking-Piret equations can be used for describing the kinetics of cell growth,sucrose consumption and flavonoids production during the process.The maximum specific growth rate(?m),the actual growth yield based on sucrose(YG) and maintenance coefficient(m) were 0.417/d,0.619g/g and 0.0206g/(g?d-1) respectively.All these outcomes could give a basis for establishing the suspension cell culture of E.ulmoides and production of the natural active components in large-scale.

Isolation and Identification of Endophytic Bacteria H-6 with High Antifungal Activity from Huperzia serrata / 微生物学通报

In this study,nearly 200 endophytic bacteria were isolated from different part of Huperzia serrata, over 60 bacterium with clear antifungal activity were selected from those cultures.Among them,strain H-6 exhibited the highest antifungal activity which was strongly inhibits the growth of many plant pathogenic fungi such as Sclerotinia scleroliorum,Fusarium graminearumt,Sclerotinia libertiana,Phytophthora capsici Leonia and Sesame fusarium wilt.According to the characteristics of morphology,physiology and biochem- istry tests and the comparison of 16S rDNA sequence,the strain H-6 was similar to the Burkholderia.So strain H-6 was identified as Burkholderia sp.H-6.The results also showed that Burkholderia sp.H-6 was markedly different from Burkholderia cepacia that was applied widely in agriculture as antagonistic bacteria. The medium and culture conditions of the strain all were optimized by single factor and orthogonal experiments.In the investigation of the culture condition,growth was carried out in a basal medium(potato juice)and gradually supplemented with the various ingredients to be investigated.The major ingredients be- ing investigated included carbon sources and nitrogen sources.The optimal antifungal activity production condition is growth in a medium(potato juice with 2.5%mannitol and 0.1%NaNO3),initial pH 4.0 at 28℃.