Biomedical subjects

K D Papadopoulos

Publications and source records attributed to K D Papadopoulos.

3 recordsLinked to original sources

PubMed1999

Electrokinetic movement of Escherichia coli in capillaries.

The movement of Escherichia coli K-12 has been studied in capillaries with an 8 microm inside diameter under a DC electric field. At low applied voltages (< 0.2 V cm(-1)), bacterial motility is the predominant mode of motion, with bacteria swimming, tumbling and moving unidirectionally towards the anode and the cathode, although a significant difference between the mean moving speeds towards the two electrodes was observed. When the electric field was removed, the mean swimming speeds were the same for both directions. At higher voltages, all the cells were swept by electro-osmotic flow exclusively towards the cathode.

Capillaries↗

PubMed1995

Unidirectional motility of Escherichia coli in restrictive capillaries.

In a 6-microns capillary filled with buffer and in the absence of any chemotactic stimuli, Escherichia coli K-12 cells swim persistently in only one direction. This behavior of E. coli can be simply explained by means of the length and relative rigidity of their flagella. Single-cell motility parameters--swimming speed, turn angle, and run length time--were measured. Compared with the motility parameters measured in bulk phase, turn angle was influenced because of the effect of the geometrical restriction.

Chemotaxis↗

PubMed1985

Shape and elasticity effects on erythrocyte electrostatic repulsion.

It is shown that the double-layer interaction between two symmetrically parallel red blood cells depends largely on their shape and elasticity. Various shapes are examined, including the realistic shape of a biconcave discocyte with an elastic membrane. It is found that changes in the shape and the elasticity of the erythrocyte may result in orders of magnitude differences in the forces and energies of pair interaction.

Elasticity↗