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The presence of proteins (albumin and globulins) in lymphedematous tissue not only gives rise to colloidosmotic pressure but also produces an electrostatic charge endowing the proteins with individual features and different migration rates. The working hypothesis of the experimental study is to transfer lymph proteins from the upper fascia accumulation area to a subfascial drainage area by subjecting them to an adequate difference in potential. A double chamber, variable volume system with separation wall able to contain a 1 cm square of muscle fascia, was designed and built; the aim of the apparatus was to reproduce the subcutaneus zone separated by the fascia interposition, from the muscle-vascular zone. At the system was applied a variable electric field in six different experiments: 4 using porous synthetic membranes and 2 using human muscle fascia.

Human leukemia K562 cells can be induced to erythroid differentiation when treated with a variety of compounds, including hemin, cytosine arabinoside and 5-azacytidine. Following erythroid induction, K562 cells express at high level gamma-globin and accumulate both Hb Portland and Hb Gower 1. In this paper we determined whether a combination treatment of K562 cells with suboptimal concentrations of cytosine arabinoside and retinoids lead to full expression of differentiated functions. Cell growth kinetics studies, intracellular detection of hemoglobin by benzidine staining and hemoglobin analysis by cellulose acetate were performed. The results obtained show that (a) retinoic acid and retinol are not able to induce differentiation of K562 cells and (b) cytosine arabinoside induces differentiation only when used at 100-300 nmol/l concentrations. In addition, our data demonstrate that erythroid differentiation of K562 occurs when 40 micromol/l of retinoic acid or retinol are added together with 75 nmol/l cytosine arabinoside.