ABSTRACT
A novel method for assaying the enzymatic activity of ribosome-inactivating proteins(RIPs) has been developed.The principle of the method is based on that RIP can remove some adenine bases from double-stranded supercoiled DNA molecules,subsequently,the deadenylated DNA was cleaved into nicked and linear form.After treatment with acidic aniline,the deadenylated DNA was degraded into many small fragments,and run out of the gel.The enzymatic activities of two RIPs(trichosanthin and cinnamomin) were tested using this method,the limit of sensitivity is about 50 ng(trichosanthin) and 5 ng(reduced cinnamomin) .It should be emphasized that the merit of this method is to avoid the preparation of ribosome.
ABSTRACT
Objective To study the effect of the extract of total flavonoids of chrysanthemum indicum(TFC) on adjuvant arthritis synovial cells. Methods 0.1ml of the complete Freund's adjuvant was subcutaneously injected into the right hind feet pads of the SD rats.24 days after immunity synovial cells in knee joint were treated with TFC and inhibition of proliferation was measured with MTT assay.DNA fragmentations were analyzed with DNA gel electrophoresis.Fluorescence staining of Hoechst 33258 to observe apoptotic body.Results The IC_50 of TFC on synovial cells was 112mg/L.DNA gel electrophoresis showed ladder-like strap.Apoptotic bodies were observed by Hoechst 33258.Conclusion TFC can inhibit proliferation and induce apoptosis in synovial cells,and exerts therapeutical effect on rheumstoid arthritis.
ABSTRACT
Objective To study a new method for extracting agarose. Methods In 1.5% agar solution, adding the cation resin exchanged by NH~+_ 4 to take off metal ions, then using the OH~ - basic resin to absorb agaropectin. Results and Conclusion The extracting rate was 57%, gel strength reached 560 g/ cm~ 2 , the agarose has good electricity function by measuring the gentian violet electrophoresis and the DNA gel electrophoresis, so it is suitable for bioche- mistry and molecular biology electrophoresis. It is a kind of simple and low cost method for extracting agarose which better than the EDTA- 2Na method and DEAE cellulose method.