J A Hendrix | Search PubMed

PubMed1985

Albumin coatings resistant to shear-induced desorption.

Using an immunoferritin-transmission electron microscopic technique, we studied the effects of C18 alkylation and fluid shear on the distribution of albumin absorbed to a segmented polyether polyurethane. Samples were exposed to 25 mg/dl albumin solution at 0, 100 or 1500 s-1 wall shear rate for 1 min. Others underwent static incubation with albumin solution for 20 mins, followed by exposure to phosphate buffered saline at 0, 100 or 1500 s-1 for 1 min. Significant increases in uniformity and density of the albumin adsorbate were observed for all C18 alkylated surfaces, at all wall shear rates. C18 alkylation also significantly decreased the rate of shear-induced desorption of albumin. Results suggest that C18 treatment may promote the rapid development and retention of an endogenous albumin layer for blood contacting materials.

Adsorption↗

PubMed1980

Integrated concentration of growth hormone in juvenile-onset diabetes.

Twenty-four-hour patterns of plasma growth hormone concentrations were evaluated during 50 studies of 42 subjects with juvenile-onset diabetes mellitus. Blood was sampled continuously over 24 h using a portable peristaltic pump under conditions in which subjects remained ambulatory and maintained their daily dietary and insulin regimens. All diabetics showed diurnal patterns characterized by frequent episodes of secretion of growth hormone. The mean 24-h concentration of growth hormone, designated the integrated concentration, was significantly higher among juvenile-onset diabetics (P less than 0.001) than it was in age- and sex-matched nondiabetic populations. Juvenile-onset diabetics younger than 20 yr had significantly higher (P less than 0.005) growth hormone integrated concentrations than did older juvenile-onset diabetics. There was no statistically significant correlation between the integrated concentrations of glucose and growth hormone; thus, the study failed to provide us with support for the hypothesis that elevated growth hormone concentrations in diabetics are a consequence of hyperglycemia. Variability of diurnal glucose concentrations was positively correlated (P less than 0.015) with the growth hormone integrated concentration among juvenile-onset diabetics. Our observations indicate that rapid declines in plasma glucose concentration or episodes of absolute hypoglycemia were significant factors, contributing to both the elevated integrated concentration and the secretory spiking of growth hormone observed in the diabetic population.

Adolescent↗

PubMed1979

Triglyceride concentrations: the disaccharide effect.

The mean 24-hour or integrated concentration of triglyceride is significantly higher when dietary sucrose is provided rather than an equivalent amount of its component monosaccharides, glucose and fructose. In contrast, the plasma triglyceride concentration after a 12-hour fast is not significantly different.

Adult↗