We hypothesized that modulation of the effective charge density of the endothelial surface layer (ESL) results in altered arterial barrier properties to transport of anionic solutes. Rat mesenteric small arteries (diameter approximately 190 microm) were isolated, cannulated, perfused, and superfused with MOPS-buffered physiological salt solutions. MOPS-solutions were of normal ionic strength (1...

The influence of ionic strength and the molecular weight of polyacrylic acid (PAA) on its adsorption and the structure of adsorbed polymer layer on SiO2 surface in the presence NaCl and CaCl2 was measured. Thickness of PAA adsorption layers on the SiO2 surface in these two electrolytes were also measured as well as the expansion coefficient (α) of PAA in CaCl2. The increase of: ionic strength, ...

Tropomyosin is a coiled-coil protein that polymerizes by head-to-tail interactions in an ionic strength-dependent manner. We produced a recombinant full-length chicken alpha-tropomyosin containing a 5-hydroxytryptophan residue at position 269 (formerly an alanine), 15 residues from the C terminus, and show that its fluorescence intensity specifically reports tropomyosin head-to-tail interaction...

The binding of proflavine to native DNA increased its stability against thermal denaturation as measured by viscometric method. Up to a moderate ionic strength of 0.058 m , the melting temperature of the complex increased almost linearly with the increase of dye concentrations and a saturation was reached when one proflavine molecule was added per four to five DNA-Phosphates {DIP c^0 .2 ). The ...

BACKGROUND The luting cements must withstand masticatory and parafunctional stresses in the warm and wet oral environment. Mouth temperature and the temperature of the ingested foods may induce thermal variation and plastic deformation within the cements and might affect the strength properties. The objectives of this study were to evaluate the effect of temperature on the compressive and diame...

During in vitro transcription of T4 DNA by E. coli RNA polymerase, chain initiation stops coincidentally with synthesis at low ionic strength (0.11) with an average of one RNA chain initiated per 24S polymerase molecule. At high ionic strength (0.37), initiation as well as synthesis continues for several hours, with an average of four chains initiated per enzyme molecule in two hours. The RNA p...

The size distribution of chromatin fragments released by micrococcal nuclease digestion of liver chromatin at various ionic strengths was examined. Below 20 mM ionic strength, gradient profiles with a peak centered at 6 nucleosomes are generated, whereas between 20 and 50 mM the peak is always centered on 12 nucleosomes, and above 50 mM ionic strength the 30-nm fiber becomes less accessible to ...

Sorption of organic contaminants by soils is a determinant controlling their transport and fate in the environment. The influence of ionic strength on nitroaromatic compound sorption by K+- and Ca2+ -saturated smectite was examined. Sorption of 1,3-dinitrobenzene by K-smectite increased as KCl ionic strength increased from 0.01 to 0.30 M. In contrast, sorption by Ca-smectite at CaCl2 ionic stre...

It is well recognized that the pK' value for the salt of a weak acid or base is significantly influenced by the ionic strength of the solution. In the case of phosphate, the theoretical value for pK2 in an infinitely dilute solution is 7.181 at 370 C. (1) and in a solution of ionic strength comparable to that of plasma is approximately 6.8. The small variations in ionic strength ordinarily enco...

Soft alginate hydrogels support robust neurite outgrowth, but their rapid disintegration in solutions of high ionic strength restricts them from long-term in vivo applications. Aiming to enhance the mechanical stability of soft alginate hydrogels, we investigated how changes in pH and ionic strength during gelation influence the swelling, stiffness, and disintegration of a three-dimensional (3D...