The classical thermodynamic treatment of osmotic pressure is quite sufficient to describe equilibrium situations and compute most quantities of interest without reference to any molecular model (see, for example, Finkelstein, 1987). However, one's intuition is always aided by molecular models, and a microscopic picture can be quite useful when thinking about osmotic flow in unfamiliar situation...

The aim of functional tissue engineering is to repair and replace tissues that have a biomechanical function, i.e., connective orthopaedic tissues. To do this, it is necessary to have accurate benchmarks for the elastic, permeability, and swelling (i.e., biphasic-swelling) properties of native tissues. However, in the case of the intervertebral disc, the biphasic-swelling properties of individu...

The rate of swelling of unfertilized sea urchin eggs in hypotonic sea water was investigated. Analysis of curves leads to the following conclusions. 1. The rate of swelling follows the equation, See PDF for Equation where V(eq)., V(0), and V(t) stand for volume at equilibrium, at first instant, and at time t, respectively, the other symbols having their usual significance. This equation is foun...

The swelling behavior of fully neutralized sodium polyacrylate gels was investigated in aqueous solutions of alkali metal (LiCl, NaCl, KCl, CsCl) and alkaline earth metal salts (CaCl2, SrCl2, BaCl2). The total salt concentration and the ratio of monovalent to divalent cations were varied in the biologically significant range. It is found that the concentrations of both monovalent and divalent c...

Bacterial protoplasts, released from confinement within the rigid wall of whole cells, imbibe water, swell, and burst unless their suspending medium contains high concentrations of solutes which have difficulty crossing the osmotic barrier in the protoplast surface membrane (C. Weibull, Exptl. Cell Res. 9:139, 1955; P. Mitchell and J. Moyle, J. Gen. Microbiol. 20:434, 1959). Hence, protoplast p...

Annotation. Edema and swelling of the brain are two stages development complex interrelated processes in substance. This pathological process occurs due to various etiological factors: injury, stroke, tumors abscesses, meningitis encephalitis, hypoxia, general toxicosis, infectious processes, body burns, occlusive hydrocephalus, malignant hypertension, osmotic imbalance. That is why purpose thi...

The effects of aniso-osmotically and amino-acid-induced cell-volume changes on bile flow and biliary taurocholate excretion were studied in isolated perfused rat liver. With taurocholate (100 microM) in the influent perfusate, hypo-osmotic exposure (225 mosmol/l) increased taurocholate excretion into bile and bile flow by 42 and 27% respectively, whereas inhibition by 32 and 47% respectively wa...

1. The matrix pyrophosphate (PPi) content of isolated energized rat liver mitochondria incubated in the presence of ATP, Mg2+, Pi and respiratory substrate was about 100 pmol/mg of protein. 2. After incubation with sub-micromolar [Ca2+], this was increased by as much as 300%. There was a correlation between the effects of Ca2+ on PPi and on the increase in matrix volume reported previously [Hal...

The purpose of this study was to investigate the efficiency of the water test to evaluate the functional membrane integrity of ejaculated canine sperm after collecting, cooling, and freezing-thawing. Twenty-five ejaculates were obtained from 12 stud dogs by digital manipulation. Sperm-rich fractions were evaluated, diluted, cooled at 5oC and frozen-thawed. A conventional hypo-osmotic swelling t...