Biorheology - Volume 31, issue 6

Authors: Goldsmith, Harry

Article Type: Other

DOI: 10.3233/BIR-1994-31601

Citation: Biorheology, vol. 31, no. 6, pp. iii-iii, 1994

Article Type: Other

DOI: 10.3233/BIR-1994-31608

Citation: Biorheology, vol. 31, no. 6, pp. III-VI, 1994

Article Type: Other

DOI: 10.3233/BIR-1994-31609

Citation: Biorheology, vol. 31, no. 6, pp. VII-VII, 1994

Authors: Adams, R.A. | Evans, S.-A. | Jones, J.G.

Article Type: Research Article

Abstract: From the known numbers and properties of normal blood cells, it is apparent that the analysis of the flow of diluted blood, through micropore filters, should allow calculation of the properties of leukocytes without the need for their prior purification. The number and transit time of a “slow” leukocyte population can be deduced by fitting the flow, of diluted blood through 5 μ m membranes over about 150 s, to the appropriate mathematical model, which is chosen by the use of a suitable statistical test-the runs test. This population of leukocytes equates numerically with the monocyte population of normal blood; …cells have a transit time, through 5 μ m pores, of 27.7 ± 10.9 s. The remaining “fast” leukocytes represent the sum of granulocytes and lymphocytes; their flow properties can be deduced from the measured initial flow rate of diluted blood and the estimated properties of the red blood cells. The properties of the red cells can be assessed from filtration of purified suspensions with any concentration of cells from 0.52 × 109 /ml to 3.0 × 109 /ml. The transit times for red cells and granulocytes/lymphocytes, in blood diluted with about an equal volume of buffer, are 1.36 ± 0.17 ms and 1.48 ± 0.33 s, respectively. The transit times of blood cells, through 5 μ D pores, are therefore inversely related to their numbers in blood. Show more

Keywords: Leukocytes, erythrocytes, filterability

DOI: 10.3233/BIR-1994-31602

Citation: Biorheology, vol. 31, no. 6, pp. 603-615, 1994

Authors: Braide, M. | Ebrahimzadeh, P.R. | Strid, K.-G. | Bjursten, L.M.

Article Type: Research Article

Abstract: The Boyden chamber technique for chemotaxis uses a mesh filter that constitutes a matrix for cell locomotion and, at the same time, creates a local restriction for convective fluid movements that allows the establishment of a diffusive concentration gradient of chemotactic substance in the filter. In the present study, the Boyden chamber was modified by the introduction of a filter sandwich that allowed cell migration both upwards and downwards and by the use of a fluid density gradient controlling cell buoyancy and mechanically supporting a movable chemotactic gradient. This method was used to study chemotaxis and random migration of human …granulocytes under the influence of gravitational forces and movable gradients of f-MLP. The results show that gravity affected cell motion significantly during random migration but not during chemotaxis. The rate of chemotactic migration was dependent on the steepness of the spatio-temporal f-MLP gradients. A stationary spatial gradient produced less migration than a gradient that was slowly moved through the filter sandwich in a direction opposite to that of the cell migration. The presence of f-MLP at constant concentration caused a minor, statistically insignificant, increase of the rate of random migration. Show more

Keywords: Cell movement, chemotaxis, neutrophils, N-Formylmethionine-Leucyl-Phenylalanine, filtration, methods

DOI: 10.3233/BIR-1994-31603

Citation: Biorheology, vol. 31, no. 6, pp. 617-630, 1994

Authors: van der Reijden, W.A. | Veerman, E.C.I. | Nieuw Amerongen, A.V.

Article Type: Research Article

Abstract: The rheological properties of a number of natural and synthetic polysaccharides have been compared with porcine gastric mucin (PGM), a mucin-containing saliva substitute (Saliva Orthana® ) and with clarified human whole saliva (CHWS). The effects of ionic strength, pH and calcium and fluoride ions on the viscoelastic properties of these polymers have been investigated. Of the polysaccharides tested, xanthan gum and scleroglucan appeared to resemble CHWS most in viscoelastic behavior and may be potential candidates for use in artificial saliva. Both PGM and Saliva Orthana® , however, did not show any elastic behavior, whereas a viscosity comparable to human saliva …was only observed in highly concentrated solutions. Of the polysaccharides tested, scleroglucan also had mucin-adhesive properties resulting in rheological synergism. This may be the first step in mucoadhesion which may protect underlying oral surfaces in vivo . Show more

Keywords: Ionic strength, mucins, pH effects, polysaccharides, saliva substitutes, viscoelasticity

DOI: 10.3233/BIR-1994-31604

Citation: Biorheology, vol. 31, no. 6, pp. 631-642, 1994

Authors: Paulitschke, M. | Preece, A. | Nash, G.B.

Article Type: Short Communication

Keywords: Erythrocyte, neuraminidase, electrophoretic mobility, membrane rigidity, micropipette, flow chamber

DOI: 10.3233/BIR-1994-31605

Citation: Biorheology, vol. 31, no. 6, pp. 643-650, 1994

Article Type: Abstract

DOI: 10.3233/BIR-1994-31606

Citation: Biorheology, vol. 31, no. 6, pp. 651-669, 1994

Article Type: Other

DOI: 10.3233/BIR-1994-31607

Citation: Biorheology, vol. 31, no. 6, pp. 671-672, 1994