[Viscoelastic characteristics of protein solutions and micromechanics of their motion in porous carriers].

The interactions of model proteins with the templates of porous carriers in biosensors were analyzed in terms of events occurring during the molecular contact of biopolymers with a solid. The viscoelastic properties of casein and albumin at small widths of the layer of the solution applied to the crystal were estimated using the dynamic method of piezoqartz resonator. The experimental data on the viscoelastic characteristics of protein solutions of different concentrations were compared with the characteristics of their tangential motion in porous carriers from cellulose nitrate. It was found that the parameters of dynamic viscosity correlate with the time of motion of protein solution in a porous polymeric carrier.

[Tetracycline sorption by alveolar macrophages of rabbits at early stages of interaction]. / Dinamika sorbtsii tetratsiklinov al'veoliarnymi makrofagami krolikov na rannykh stadiiakh vzaimodeistviia.

Interaction of rabbit alveolar macrophages with morphocycline, tetracycline and methacycline was studied. The use of the membrane microfiltration technique in investigation of the antibiotic absorption by the macrophages provided description of the time course of the drug interaction with the cells at its early stages. It was shown that the macrophages mainly absorbed the tetracyclines within the first 20 seconds (1 minute incubation). Later, within the period of 1-5 minutes no significant time course was observed. The medium temperature within 4-37 degrees C and the number of the cells in the system (0.1-5 minutes no significant time course was observed. The medium temperature within 4-37 degrees C and the number of the cells in the system (0.5-1 million/ml) had no effect on the parameters of the tetracyclines sorption by the macrophages. The percentage of the decrease of the morphocycline level in the extracellular medium was stable at the drug concentration in the cells ranging within 10-50 micrograms/ml. The respective figures for tetracycline and methacycline were 10-100 and 10-5000 micrograms/ml. Further increasing of the concentration of the antibiotics in the incubation medium resulted in a significant lowering of the percentage of their binding. It was suggested that absorption of the tetracyclines by the cells was associated with their intracellular binding.