Effects of nuclear factor-kappa B p65 ASODN on transforming growth beta-1 and intercellular adhesion molecule-1 of rat hepatic stellate cells / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the effects of nuclear factor (NF)-kappa B p65 ASODN on transforming growth factor beta-1 (TGF beta 1) and intercellular adhesion molecule-1 (ICAM-1) of rat hepatic stellate cells (HSC) and the mechanisms of NF-kappa B p65 ASODN in treating liver fibrosis.</p><p><b>METHODS</b>Type IV collagen enzyme digestion and density centrifugation methods were used to separate rat hepatic stellate cells. NF-kappa B p65 ASODN was manually synthesized and completely phosphorothioate-modified. The changes of TGF beta 1 and ICAM-1 mRNA were detected by RT-PCR and albumen of TGF beta 1 and ICAM-1 were detected by ELISA. The changes of NF-kappa B activity were determined by ELISA.</p><p><b>RESULTS</b>NF-kappa B activity and the expressions of ICAM-1 and TGF beta 1 increased after the HSC were treated by TNF alpha. NF-kappa B activity weakened after being treated with NF-kappa B p65 ASODN (0.001-1.000 micromol/L), P less than 0.05 in a dose dependent manner. Transferring NF-kappa B p65 ASODN (0.001-1.000 micromol/L) also weakened the expression of ICAM-1 and TGF beta 1 mRNA and the protein induced by TNF alpha in HSC. It was also in a dose dependent manner, P less than 0.05.</p><p><b>CONCLUSIONS</b>After transferring NF-kappa B p65 ASODN into HSC, their NF-kappa B activity decreased, and their mRNA and protein expressions of ICAM-1 and TGF beta 1 also decreased. This may serve as a new way in treating hepatic fibrosis.</p>

The Progress of Recombinant Escherichia coli for Production of Succinic Acid / 微生物学通报

Succinic acid is regarded as C4 platform chemical, which has a huge potential market with wide applications in biopolymer, food, medicine, and so on. Production of succinic acid by microorganism fer-mentation has attracted much attention in recent times. By fermentation, succinic acid could be produced from renewable resources in place of petroleum with low cost and low pollution; especially CO2 could be fixed by microorganism to form the product, which is a promising way to deal with the green gas. Some E. coli have been chosen as good succinic acid producing strains because of their clear genetic backgrounds, convenience to be modified and controlled, and good growth properties with low nutrients requirements. The progress of genetic engineering strategy and metabolic engineering technology for construction of succinic aicd producing recombinant E. coli has been introduced in this paper with the discussion of the future re-search in this area.

The Application of Ultra High Hydrostatic Pressure in the Screening of Succinic Acid Producing Strain / 微生物学通报

Actinobacillus succinogenes A3 was mutagenized by ultra high hydrostatic pressure for improving the production ability of succinic acid.The effects of pressure,rate of pressure changes and growth periods on the lethality rate of the strain were investigated.The strain in stationary phase was mutagenized at 200 MPa with the pressure changes at the rate of 50 MPa/min.As a result,a mutation strain Actinobacillus succinogenes B19 was obtained,and the concentration of succinic acid could reach 32.2 g/L,which was 17.9%higher than that of the original strain,and in the meanwhile the concentration of acetic acid was decreased by 11.5%.After six generation,the mutant also has good stability of descendiblity for succinic acid production.