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Biomedical subjects

R A Caputo

Publications and source records attributed to R A Caputo.

11 recordsLinked to original sources
PubMed1993

Volatile substance misuse in children and youth: a consideration of theories.

A paucity of research exists in the social sciences regarding the theories explaining volatile substance misuse behavior in children and adolescent. Volatile substances include solvents and inhalants such as modeling glue, aerosol sprays, and gasoline. The explanations found in the literature neither sufficiently nor adequately explain possible motivation and causation. Cultural ideas about life and alcohol, as perceived by adult community members, are significant contributing and motivating variables in children's choices to misuse volatile substances. The social forces within cultural frameworks must be acknowledged to better understand youthful choices to misuse substances.

Adolescent↗
PubMed1981

Heat Resistance and Population Stability of Lyophilized Bacillus subtilis Spores.

Bacillus subtilis 5230 spores were lyophilized in 0.067 M phosphate buffer and stored at 2 to 8 degrees C for 9 to 27 months. The lyophilized spores were reconstituted with buffer or 0.9% saline, and the heat resistance was determined in a thermoresistometer. Lyophilization had no effect on the heat resistance of the spores but did result in a slight decrease in population (</=0.3-logarithm reduction). The lyophilized spores maintained heat resistance and population levels over the test periods. The D-values ranged from 0.44 to 0.54 min at 121.1 degrees C, and the z-values ranged from 6.1 to 6.6 degrees C. Lyophilization was concluded to be an acceptable alternative for storage of bacterial spores that are to be used as biological indicators in sterilization processes.

Journal Article↗
PubMed1979

Dissociation of the diurnal variation of aldosterone and cortisol in anephric subjects.

Diurnal variation of plasma aldosterone and cortisol concentration in man was studied in 13 anephric subjects and 7 normal subjects. All subjects were ambulatory and active throughout the study except during an 8-hour sleep period. Six anephric subjects received Kayexalate (sodium polystyrene sulfonate) during the studies to prevent potassium accumulation and increase in plasma potassium concentration. Diurnal variation of plasma aldosterone concentration with peak and nadir concentrations at 12:00 noon and 12:00 midnight respectively was demonstrated in the studies on normal subjects. Changes in plasma aldosterone concentration were not significantly correlated with changes in plasma concentration but were highly correlated with changes in PRA (P less than 0.001). There was a highly significant correlation between plasma aldosterone and potassium concentration in the anephric subjects studied without Kayexalate administration (P less than 0.001). In the anephric subjects who received Kayexalate, plasma aldosterone and potassium concentration remained stable, and no correlation could be demonstrated. No diurnal variation of plasma aldosterone concentration could be demonstrated in either group of anephric subjects, whereas plasma cortisol concentration varied as in the studies on normal subjects. Conclusion. Diurnal variation of plasma aldosterone concentration is dependent on continued stimulation by the renin-angiotensin system. Loss of this stimulation has no demonstrable effect on the diurnal variation of plasma cortisol concentration.

Adult↗
PubMed1975

Rapid determination of the amount of cetylpyridinium chloride bound by bacteria.

A modification of the Colowick and Womack procedure for measuring ligand binding by macromolecules is described for drug binding by bacteria. This technique is based on the determination of drug concentration in the dialysate from a bacteria-drug mixture at equilibrium. The dialysis cell of the original procedure was replaced by a Minibeaker (Bio-Rad), which has a larger membrane surface area, and the dialysate was continuously monitored with a spectrophotometer equipped with a flow cell. With this system, only 3 min was required to determine the amount of cetylpyridinium chloride bound by Escherichia coli K-12 strain P678. Possible applications of the technique are discussed.

Absorption↗