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Biomedical subjects

L Campbell

Publications and source records attributed to L Campbell.

At least 181 records · Page 10Linked to original sources

Mechanism of action of SCN in isolated gastric glands.

Isolated gastric glands were used to study the mechanism of acid secretory inhibition by thiocyanate (SCN). It was found that SCN does not act as a competitive antagonist of histamine nor does SCN prevent the increase in cellular cAMP associated with histamine stimulation. SCN modifies but does not prevent the expansion of parietal cell canaliculi, indicating that this characteristic morphological transition does not require the actual formation of hydrochloric acid. Low doses (less than 5 mM) of SCN were found to inhibit aminopyrine accumulation, an index of acid formation, but do not inhibit either resting or stimulated respiration. Higher doses (greater than 10 mM) of SCN produce significant inhibition of stimulated but not resting respiration. These results indicate that SCN has two actions, i.e., inhibition of acid formation that requires low doses and inhibition of oxidative metabolism that requires higher doses. Incubation of glands in high-K+ (108 mM) medium leads to formation of an acid gradient in the absence of other secretagogues. The gradient was found to be transient, and its formation does not require oxidative metabolism, indicating that continued proton pumping is not required. Low doses of SCN were found to be more effective in dissipating the high-K+-induced gradient than a similar gradient induced by histamine stimulation. These results support the hypothesis that SCN inhibits acid secretion by increasing the rate of proton-gradient dissipation rather than interfering with a proton-pump mechanism.

Aminopyrine↗

A factor analytic study of effectiveness criteria in intercollegiate athletics.

The study was concerned with developing a set of effectiveness criteria for intercollegiate athletics and assessing the importance of these criteria as viewed by a sample of students in a Canadian University. The responses to 46 items selected from a larger pool of items were factor analyzed. An 11-factor solution was accepted as the most meaningful. Further analysis showed that the students were generally homogeneous in rating Satisfaction of Athletes, Spectator Appeal, Student Recruitment, and Sharing of Costs as the four most important criteria that should be used in evaluating the effectiveness of athletic teams. There were, however, differences among the sexes and among the physical education and general students. Since different criteria will be used by different decision makers reflecting the various objectives they hold for the program, it was stressed that further study be conducted with different sets of decision makers.

Female↗

Haloperiodl in the treatment of stuttering.

Haloperidol treatment for stuttering was examined in a double-blind cross-over study of 26 adult volunteers with long-standing stuttering. Most had had unsuccessful speech and drug therapy. During the three-month study, their speech and stuttering patterns were repeatedly evaluated from videotaped readings of a standard passage and during spontaneous speaking. Of the 18 patients completing the trial 11 were significantly more improved on haloperidol than on placebo, three benefited equally from both, and four were unchanged. Improvement over placebo was indicated by fewer dysfluencies, increased speed of speaking, and reduced secondary "struggle" phenomena. Side effects were common on a dosage of 3 mg haloperidol daily. Poor concentration, akathisia and dystonic movements caused 8 patients to discontinue the trial despite significant improvement in 5 of them. Although "statistically significant" improvement occurred in most patients on haloperidol, the "clinical significance" of this form of therapy will be limited by the partial response, the need for continuous medication, the side effects of haloperidol and the attitude of stutters to this type of therapy.

Adolescent↗

Carrier solutions for low-level intravenous insulin infusion.

In the use of low-level intravenous insulin infusion for treating diabetic hyperglycaemia and ketoacidosis adsorption of insulin to containers or plastic infusion apparatus results in significant losses of 60-80% of insulin in dilute physiological saline solution (40 U/l). It is therefore necessary to add protein to the carrier solution to minimize losses and maintain a constant delivery rate. Recovery studies showed that 3.5% w/v polygeline solution (polymer of degraded gelatin) was a suitable medium for this purpose, offering some advantages over human serum albumin. A minimum concentration of 0.5% polygeline was required to ensure adequate delivery of insulin to the patient.

Biological Availability↗