Disease relevance of Surface Tension

• Minimum surface tension and cholesterol from traumatized cats which developed convulsive seizures immediately after the blow were more than doubled while no change was seen in traumatized cats without seizures [1].
• Minimum surface tension was higher in CF patients compared to patients with chronic bronchitis (p less than 0.05) [2].
• It is speculated that, in conditions such as hyperoxia and radiation pneumonitis, altered surface tension properties may result in uneven reinflation of the lungs after degassing and that nonuniform reinflation may produce spurious shifts in the shape as well as the amplitude of PV curves [3].
• Severity of lung disease as reflected by the peak inspiratory pressure needed to normalize Pco2 values decreased as surfactant-saturated phosphatidylcholine pool sizes increased (r values greater than 0.90) and minimum surface tensions of alveolar washes decreased, but the distention procedure did not change these relationships [4].
• Surfactin produced by Bacillus subtilis (ATCC 21332) was used to examine the effect of altering salt concentration, pH, and temperature on surfactin activity (as measured by reductions in surface tension) [5].

High impact information on Surface Tension

• The possibility that the lipoprotein complex of lung surfactant functions in pulmonary host defense as well as lowering surface tension at the air-liquid interface has been the subject of renewed interest in light of the finding that surfactant proteins A and D (SP-A and SP-D) are members of a family of proteins known as collectins [6].
• These data, together with findings that the SP-B-related peptides increase inter- and intramolecular order of the phospholipid layer, suggest that SP-B resists surface tension by increasing lateral stability of the phospholipid layer [7].
• This value, when used in a simple geometric model for the curvature dependence of the hydrophobic effect, predicts a macroscopic alkane-water surface tension that is close to the macroscopic value [8].
• We thus conclude that the amyloid-like fibrils of ChpD-H lower the water surface tension to allow aerial growth and cover aerial structures, rendering them hydrophobic [9].
• The crude surfactant pellet was analyzed for total phospholipids (PL), individual phospholipids, SP-A, SP-B, and minimum surface tension (STmin) [10].

Biological context of Surface Tension

• Surfactant isolated from SP-A(-/-,D/A) mice exhibited elevated surface tension both in the presence and absence of plasma inhibitors, but whole lung compliance of the SP-A(-/-,D/A) animals was not different from the SP-A(-/-) littermates [11].
• In all cases, the hybrid compound's ability to increase solvent surface tension was the strongest predictor of its effect on Abeta aggregation kinetics [12].
• Amino acid substitutions in synthetic peptides corresponding to the N-terminal half of SP-B indicated that, in general, decreased fusion or lytic activities were associated with altered surface tension reducing properties of the peptide [13].
• Aqueous solution surface tension (pressure) as a function of vapor-phase trichloroethene (TCE) pressure isotherms were measured at atmospheric pressure at 287.2, 291.2, 297.2, 303.2, and 315.2 K using a flow-through vapor adsorption method [14].
• Lipid peroxidation was measured using the thiobarbituric acid method. *OH had broad inhibitory effects on surface tension parameters, including adsorption, minimum surface tension, percentage film area change and film compressibility [15].

Anatomical context of Surface Tension

• SP-B is a protein in pulmonary surfactant that is, in greatest part, responsible for resistance to surface tension and prevention of collapse of pulmonary alveoli [7].
• Allergen challenge of asthmatics, but not of healthy volunteers, significantly increased eosinophils, proteins, SA/ LA, and surface tension at minimum bubble size, and diminished the time the capillary tube is open [16].
• We characterize two assays of total amniotic fluid surfactant that are based on function: the surface-tension lowering ability of extracts of amniotic fluid lipid (I) and the foam stability index test (II) [17].
• The protein-free synthetic surfactants Exosurf and Pumactant did not reach minimum surface tension <10 mN/m even in the absence of meconium [18].
• In the water/ethanol mixture, only Fluorad lowered the surface tension from 29.2 to 19.7 mJ.m-2 at 25 degrees C. On bovine dental enamel, all surfactant solutions showed a significantly lower contact angle than did distilled water [19].

Associations of Surface Tension with chemical compounds

• Addition of propanol reduced the surface tension of the suspending liquid, and decreased adhesion of piliated RDEC-1 to polystyrene by 80% [20].
• Various treatments were studied, including disruption by surface tension forces, very low salt concentrations, and nonionic detergents such as Triton C-100 and Nonidet P-40 [21].
• By layering intact lamellar bodies on the surface of a more dense sucrose subphase, we studied the factors affecting film formation from surface tension-vs-time data and determined surface tension-surface area isotherms by compression and expansion of the resulting films [22].
• The increased surface-tension effects do not overbalance these solvation effects since they are smaller than the large surface-tension increases with lithium chloride, a typical salting-out agent [23].
• The salting-in agent tetra-n-butylammonium chloride differs in that it lowers the surface tension of water [23].

Gene context of Surface Tension

• At lower concentrations, minimum surface tensions were higher for SP-A(-/-) mice [24].
• Surfactant protein A (SP-A) is the major protein component of pulmonary surfactant, a material secreted by the alveolar type II cell that reduces surface tension at the alveolar air-liquid interface [25].
• SP-C associates with surfactant lipids to reduce surface tension within the alveolus, maintaining lung volume at end expiration [26].
• SP-C enhances surface tension lowering activity of surfactant phospholipids that is critical to the maintenance of alveolar volume at end expiration [27].
• The surface tension measured with a Wilhelmy balance of the rSP-C surfactant was lower than the surface tension of natural sheep surfactant (containing SP-B and SP-C) [28].

Analytical, diagnostic and therapeutic context of Surface Tension

• The Langmuir trough has been used to study monolayers of surfactant from beef lung extracts, dog lavage and the principal component (dipalmitoyl lecithin; DPL) in which surface tension has been simultaneously monitored on each film by the Wilhelmy method and the original Langmuir method whose readings are independent of contact angle [29].
• Median minimal surface tension, measured by pulsating bubble surfactometer, was elevated (P < 0.01) in both infection (17.5 mN/m) and CF (17.1 mN/m) compared with the control group (1.5 mN/m) [30].
• CONCLUSIONS: Exogenous surfactant preceding high peak inspiratory lung volumes prevents impairment of oxygenation, lung mechanics, and minimal surface tension of bronchoalveolar lavage fluid and reduces alveolar influx of Evans blue dye [31].
• Dilute mixed solutions of non-surface active anionic polymers (polyacrylamide and polystyrene sulfonate, xanthan) and various surfactants have been studied with several methods: surface tension, ellipsometry, X-ray and neutron reflectivity, thin film balance, surface and bulk rheology [32].
• Minimum surface tensions of alveolar washes fell from greater than 30 dynes/cm to 6.3 dynes/cm 10 min after treatment and again rose to 21.6 dynes/cm within 3 h [33].

References