Adolescent idiopathic scoliosis.

Adolescent idiopathic scoliosis, a lateral curvature of the spine, is an insidious disorder that usually occurs in previously well children. The onset is generally during the growth spurt of the early teens. While a potentially disabling disease entity, serious deformity can be averted through early detection and proper management. The nurse can be instrumental in this procedure by learning the necessary examination techniques and conscientiously screening all susceptible patients entering the health care setting.

Hydration of pectic polysaccharides.

The hydration and swelling of pectic polysaccharides was examined at different pHs and ionic strengths as a function of osmotic stress. For weakly charged pectic polysaccharides at low concentrations of a monovalent salt (20 mM), the main driving force for swelling originates from a polyelectrolyte effect due to the translational entropy of ions within the film. Swelling is reduced at higher salt concentrations and lower pHs. Polyelectrolyte collapse and minimal swelling is observed for more highly charged pectic polysaccharides. Replacement of the Na(+) counterion with Ca(2+) results in minimal swelling and the formation of network structures even for the weakly charged pectic polysaccharides.

Swelling behavior of the tomato cell wall network.

The swelling of tomato pectin and isolated tomato pericarp cell wall material was investigated in aqueous media under different ionic conditions, pH, and external osmotic stress. Conditions were chosen to include those that would be encountered in vivo. Swelling in these systems was strongly influenced by the polyelectrolyte nature of the polymer and the extent of cross-linking with divalent counterions.