Objective To quantitatively analyze type 1 receptor of insulin-like growth factors (IGF1Rs) on the HepG 2 cells. Methods 1H7 (monoclonal antibody against IGF1R) was labeled with radionuclide 131 I by Iodogen method. The mixture was purified with Sephadex G-50 column, 131 I-1H7, and its unlabeled counterpart 1H7 competitively bound to IGF1Rs on the HepG 2 cells. The average number of IGF1R on the HepG 2 cells was analyzed by Scatchard method. Results The Bmax of HepG 2 cells (2.0?10 5) in every well was 6.746?10 -12 mol/L. The expression of IGF1R on the HepG 2 cells was 2.03?10 4/cell. Conclusion IGF1Rs are expressed on the HepG 2 cells with high density and high affinity, which may be used in other related studies.

Aims: A new methanogenic strain, named GFJ07, was isolated from a pond of mountain forests in Guangxi, China. Cells grown in liquid culture tended to form aggregates with pseudosarcina-like or irregular shape. Methodology and Results: The optimum temperature, pH and NaCl concentration were 35 ℃, 7.0 and 0.5%, respectively. The isolate used methanol, trimethylamine, acetate and H2-CO2 as substrates. Analysis of the 16S rDNA sequences revealed strain GFJ07 showed the highest sequence similarity of 99.9% to Methanosarcina mazei. Conclusion, significance and impact of study: The cells were Gram positive and nonmotile. Most of single cell grew as a sausage-like clinder about 0.5 μm in diameter and 1.0 μm in length.

Transcription, Genetic