Purchase individual online access for 1 year to this journal.
Price: EUR 90.00
Impact Factor 2017: 1.078
Biorheology is an international interdisciplinary journal that publishes research on the deformation and flow properties of biological systems or materials. It is the aim of the editors and publishers of
Biorheology to bring together contributions from those working in various fields of biorheological research from all over the world. A diverse editorial board with broad international representation provides guidance and expertise in wide-ranging applications of rheological methods to biological systems and materials.
The aim of biorheological research is to determine and characterize the dynamics of physiological processes at all levels of organization. Manuscripts should report original theoretical and/or experimental research promoting the scientific and technological advances in a broad field that ranges from the rheology of macromolecules and macromolecular arrays to cell, tissue and organ rheology. In all these areas, the interrelationships of rheological properties of the systems or materials investigated and their structural and functional aspects are stressed.
The scope of papers solicited by
Biorheology extends to systems at different levels of organization that have never been studied before, or, if studied previously, have either never been analyzed in terms of their rheological properties or have not been studied from the point of view of the rheological matching between their structural and functional properties. This biorheological approach applies in particular to molecular studies where changes of physical properties and conformation are investigated without reference to how the process actually takes place, how the forces generated are matched to the properties of the structures and environment concerned, proper time scales, or what structures or strength of structures are required.
Biorheology invites papers in which such 'molecular biorheological' aspects, whether in animal or plant systems, are examined and discussed. While we emphasize the biorheology of physiological function in organs and systems, the biorheology of disease is of equal interest. Biorheological analyses of pathological processes and their clinical implications are encouraged, including basic clinical research on hemodynamics and hemorheology.
In keeping with the rapidly developing fields of mechanobiology and regenerative medicine,
Biorheology aims to include studies of the rheological aspects of these fields by focusing on the dynamics of mechanical stress formation and the response of biological materials at the molecular and cellular level resulting from fluid-solid interactions. With increasing focus on new applications of nanotechnology to biological systems, rheological studies of the behavior of biological materials in therapeutic or diagnostic medical devices operating at the micro and nano scales are most welcome.
Abstract: We have investigated changes in cellular deformability during promyelocytic leukemic HL-60 cell maturation. HL-60 cells were induced to mature with 1.25% dimethyl sulfoxide. Cellular deformability was evaluated by single-cell micropipette aspiration at one day, four days and seven days after induction. HL-60 cells were found to decrease in size and increase in deformability with maturation. When tested under the same aspiration pressures (0.5–1.3 kPa), cytoplasmic viscosity was found to vary from 210 to 85 Pa·s for cells prior to induction; it varied from 85 to 40 Pa·s for cells seven days after induction. Further, cytoplasmic viscosity exhibits power-law dependence on…shear rate, μ = μ c ( γ m / γ c ) − b , where μ is cytoplasmic viscosity, γ m is mean shear rate during cell entry, μ c is the characteristic viscosity at the characteristic shear rate, Ye, and b is a material coefficient. Cells of all maturities showed similar dependence on shear rate (b ≈ 0.5 ), but the characteristic viscosity decreased with maturation except for Day 1. When γ c was set to 1 s-1 , μ c = 236 ± 5 Pa · s for cells prior to induction, μ c = 239 ± 7 , 209 ± 7 and 175 ± 14 Pa·s for cells on Days 1, 4 and 7 of induction, respectively.
Abstract: We measured the specific hydraulic conductivity (K) of the human and bovine aortic wall, two tissues for which K has not been previously reported in the literature, and examined the effects of aging (human) and development (bovine) on K. As part of the study, we also examined the effects of mounting the tissue in a flat or cylindrical configuration and the effects of perfusion pressure. With aging, in the human, we found a modest increase of K with age in a flat geometry; this trend was not apparent in a limited number of measurements in a cylindrical geometry. No significant…dependence of K on developmental stage was found in the bovine aortic wall perfused in either a flat or cylindrical geometry. Our results indicate that aging and developmental changes of the aortic extracellular matrix have minimal effects on its hydrodynamic transport properties as measured. Mounting geometry for the aorta has been a concern reported in the literature since Yamartino et al. (1974) reported that K in the rabbit was 10-fold lower when measured in a flat geometry than in a cylindrical geometry. We found mounting geometry to make only a small difference in the calf and the cow, (Kflat approximately 2/3 of Kcylindrical ), and in the human, we found K to be somewhat higher in the flat geometry than in the cylindrical geometry. Higher perfusion pressures decreased K of bovine tissue in the flat geometry, but pressure was not found to have a significant effect on K in the cylindrical geometry. An analytical model demonstrated that the anisotropic nature of the aortic wall allows it to be compressible (water-expressing) and yet remain at nearly constant tissue volume as the aorta is pressurized in a cylindrical geometry.
Abstract: Smoking and elevated leukocyte counts are risk factors for cardiovascular disease. Experimental studies suggest that leukocyte activation may be a requirement for certain cardiovascular complications. Clinical studies have demonstrated activated leukocytes in the peripheral blood of stroke victims. Accordingly, neutrophil activation in unseparated whole blood of smokers as well as naive neutrophils of non-smokers exposed to plasma of smokers was investigated. Both spontaneous superoxide formation as determined by nitroblue tetrazolium reduction, as well as pseudopod formation, are significantly elevated in autologous neutrophils of smokers. The surface expression of CD18 and L-selectin on autologous circulating neutrophils of smokers is not significantly…different from non-smoker controls. In contrast, incubation of naive neutrophils with smoker plasma leads to significantly higher levels of superoxide formation, pseudopod formation, and L-selectin shedding, compared with non-smoker plasma, suggesting that the plasma of smokers contains a transferable factor which causes leukocyte activation. The results indicate that analysis of blood samples from large peripheral veins may not accurately reflect leukocyte activation in the circulation since activated leukocytes have a higher probability to be trapped in the microcirculation.
Keywords: Adhesion, selectin, integrin, superoxide, actin, pseudopod formation, organ injury
Abstract: Based on the variation in the optical density due to erythrocyte concentration and movement, the axial tomographic and image velocimetry techniques are respectively applied to determine the flow field, i.e., the distribution of erythrocytes and axial and radial velocity components, in steady blood flow through a curved glass capillary with a diameter of 180 µm. The data at four positions (two straight and two curved segments of the capillary) are recorded by a video-microscopic system on a video cassette. The erythrocyte and velocity distribution profiles change from symmetric at the straight position to an asymmetric shape at the curved sections.…These profiles become symmetric again at the straight section of the capillary. The increase in the radial velocity component at curved portions is attributed to the secondary flow. The tomograms obtained by concentration profiles show respective changes in the cellular population at various cross-sectional positions. The kinetic energy dissipation, as calculated based on a determination of the flow field, is the minimum for the observed profiles. Any deviation towards parabolic form leads to the dissipation of a higher amount of energy.