In vitro differentiation of human endometrial stromal cells: effect of transforming growth factor beta 1 on prolactin secretion.

OBJECTIVE: To investigate the role of Transforming Growth Factor beta 1 on differentiation of human endometrial stromal cells. STUDY DESIGN: A prospective study. MATERIAL AND METHODS: Human endometrial cells obtained from 9 women were cultured in DMEM-HAMs F12 media to adequate cell confluence and then the flasks were cultured in the presence and absence of TGF b 1. The influence of TGF beta 1 were measured by prolactin production expressed as nanograms of prolactin/mg of total DNA in cells measured by diphenylamine reaction. RESULTS: The levels of prolactin in the culture medium with and without TGF beta 1 were 0.16 +/- 0.27 ng/microgram DNA/day and 0.24 +/- 0.41 ng/microgram DNA/day respectively. There was no significant difference between groups. CONCLUSION: There is no direct effect of TGF beta 1 on differentiation of human endometrial stromal cells. However it may involve in more complex relationship in this process.

Preparation of polyethyleneglycol (PEG) coatings for microencapsulation of charcoal.

Polyethyleneglycols (PEGs) with their high solubility in water cannot normally be used as a coating material in aqueous solutions such as blood. A gamma-radiation procedure was therefore applied after coating charcoal granules with PEG in a non-aqueous phase, and an 80-90% insoluble polymer matrix on charcoal was obtained. PEGs with different molecular weights from 4000 to 300,000 were used for coating. The performance of this system was determined by using several test solutes, namely creatinine, uric acid, and vitamin B-12. It was observed that the pore size and structure of these membranes can be adjusted by changing the irradiation time and by using PEGs with different molecular weights. Thus, very high mass transfer rates can be achieved.

A new combined enzyme-charcoal system adsorption on charcoal followed by polymer coating.

A method is described for a new combined enzyme-charcoal system. A model enzyme, urease, was adsorbed on activated charcoal granules which was then coated with ultrathin cellulose nitrate. The assayed activity of this immobilized enzyme was 28.1% /+- 3.12% (mean /+- S.D.) of the activity of urease in solution. The enzyme did not leak out after immobilization and worked efficiently. The assayed urease activity increased with greater amounts of urease/gm immobilized enzyme, but reached a plateau after 40 sumner units/gm. Immobilized urease has good storage and operational stabilities at refrigerator, room and body temperatures. In-vivo studies show that about 90% conversion urea in one single pass is possible.