Biomedical subjects

P C O'Connor

Publications and source records attributed to P C O'Connor.

At least 19 recordsLinked to original sources

PubMed1996

Academic outcomes and stress in full-time day and part-time evening baccalaureate nursing students.

This study examined differences in stress and academic outcomes in generic baccalaureate nursing students enrolled in a full-time day program and those enrolled in a part-time evening program. The study also sought to identify the relationship between stress and academic outcomes and between selected demographic variables and stress in these two groups of nursing students. Day and evening students did not differ on trait or state anxiety scores measured at the beginning of the semester; by mid-semester, state anxiety scores increased in evening students only. Nevertheless, no relationship between stress and academic outcomes was found in either group. Of the demographic variables examined, age and number of dependents were related to stress. There was no relationship between hours employed and stress scores. Students enrolled in an evening nursing program were able to achieve academic outcomes comparable to their day counterparts despite reporting greater stress and more hours spent in employment each week. The high stress reported by both day and evening students has implications for the development of support programs and stress reduction interventions in nursing schools.

Adult↗

PubMed1995

Anatomy and physiology as a predictor of success in baccalaureate nursing students.

The purpose of this two-part study was to identify early indicators of students' success (N = 98) in a baccalaureate nursing program. Part I determined how well six variables predicted competence on a criterion-referenced anatomy and physiology (A/P) examination. A multiple regression model was used to analyze the relationships among the predictor and the criterion variables. Data analyses show that only two predictors, grade point average and type of college in which the A/P course was taken, were significantly related (p = 0.0001) to A/P test scores. Part II used students' A/P score to predict success in the didactic component of clinical nursing coursework. In part II, a simple regression model was used to predict the relationship between A/P test score and success in the second clinical nursing course. These results indicated that A/P test score was significantly related (p = 0.003) to success in the second clinical nursing course.

Anatomy↗

PubMed1986

Effects of ICI 141,292 on exercise tachycardia and isoprenaline-induced beta-adrenoceptor responses in man.

The beta-adrenoceptor blocking properties and cardioselectivity of ICI 141, 292 were investigated in healthy male subjects. Seven subjects received in random order oral doses of ICI 141,292 20, 50, 100, 200 and 400 mg, atenolol 50 and 100 mg and placebo. ICI 14 292 had no effect on supine heart rate which was reduced by atenolol 100 mg. ICI 141,292 50, 100 and 200 mg had no effect on standing heart rate which was reduced by 400 mg at 2 h. Both doses of atenolol caused greater reductions. The maximum percent reduction of an exercise tachycardia after ICI 141,292 200 mg (23.9 +/- 3.7%) and 400 mg (24.3 +/- 5.2%) were similar to atenolol 50 mg (27.3 +/- 4.7%) but less than atenolol 100 mg (30.8 +/- 2.9%) (P less than 0.02). Six subjects received in random order single oral doses of ICI 141,292 100, 200 and 400 mg, atenolol 50 mg, propranolol 40 mg and placebo. Following each dose each subject received graded infusions of isoprenaline sulphate until heart rate increased by 40 beats min-1. Dose-response curves were constructed for the changes in heart rate, finger tremor, blood pressure and forearm blood flow produced by each infusion. At the 4 micrograms min-1 dose of isoprenaline, ICI 141,292 200 mg caused more attenuation than atenolol 50 mg but less than propranolol 40 mg in the changes of heart rate, diastolic blood pressure and finger tremor (P less than 0.02). ICI 141,292 400 mg caused more attenuation of the changes of all parameters than atenolol 50 mg but less attenuation of the changes in diastolic blood pressure and finger tremor than propranolol 40 mg (P less than 0.02). These results indicate that ICI 141,292 is a cardioselective beta-adrenoceptor antagonist with partial agonist activity.

Adrenergic beta-Antagonists↗

PubMed1985

Human pharmacokinetic and pharmacodynamic studies on Ro31-1118, a new beta-adrenoceptor antagonist.

The pharmacokinetic and pharmacodynamic effects of Ro31-1118 were examined in groups of healthy volunteers. In three subjects given 10 mg of [14C]-Ro31-1118 orally, peak levels of radioactivity (84 +/- 5 ng/ml) were 16 times those of the parent drug (approximately 5 ng/ml). Very little parent drug was recovered in the urine, although recovery of total radioactivity was nearly 80% in the urine by day 5. In five subjects studied after both oral and intravenous administration of 20 mg Ro31-1118 the average bioavailability was 57% (range 41-73%). Following intravenous infusion the apparent volume of distribution for the five subjects averaged 590 1 (range 510-700 1). The elimination half-life averaged 18 h (range 17-26 h). In eight subjects who received 40, 80, 160 and 320 mg of Ro31-1118 orally there was a linear relationship between dose and plasma concentration (r = 0.999) and between dose and AUC (r = 0.996). Ro31-1118 had no effect on resting heart rate whereas atenolol reduced resting heart rate up to 6 h after all doses. The maximum reduction of an exercise tachycardia after Ro31-1118 (320 mg) was 23.13 +/- 0.7% and compared with atenolol (100 mg) was 28.2 +/- 1.25%. At 24 h the percentage reduction after Ro31-1118 was 21.5 +/- 1.7%, while after atenolol the percentage inhibition had decreased to 11.1 +/- 1.6%. In three subjects Ro31-1118 (160 mg) orally had no effect on resting heart rate, forearm blood flow and systolic blood pressure, while atenolol (50 mg) reduced all three parameters.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Antagonists↗

PubMed1985

The effects of propranolol and digoxin on the acute vascular responses to frusemide in normal man.

To examine the importance of acute frusemide-induced renin release in the production of the acute peripheral venous and arterial responses to frusemide in man, the effects of two drugs, previously described as inhibitors of acute frusemide-induced renin release, propranolol and digoxin, were examined. Propranolol abolished the acute increases in venous capacitance and blood pressure and attenuated the increases in forearm vascular resistance produced by frusemide. The acute increases in plasma renin activity and plasma aldosterone concentrations were also abolished. Pre-treatment with digoxin had no effect on the acute peripheral vascular responses to frusemide and failed to inhibit the acute increases in plasma renin activity and plasma aldosterone produced by frusemide. The study provides further evidence of a relationship between acute frusemide-induced renin release and the acute peripheral vascular effects of frusemide in man.

Adolescent↗

PubMed1985

Effects of the beta 2-adrenoceptor antagonist ICI 118,551 on exercise tachycardia and isoprenaline-induced beta-adrenoceptor responses in man.

ICI 118,551, 5 to 80 mg orally, did not significantly alter resting heart rate or blood pressure. In doses less than 40 mg the reduction in exercise tachycardia was under 10 beats/min. ICI 118,551, 10 to 40 mg, did not appear to reduce the maximum rise in systolic pressure with isoprenaline but did attenuate the changes in diastolic pressure, forearm blood flow and finger tremor. It also attenuated the isoprenaline-induced changes in serum glucose, insulin and potassium. On these observed changes, the effect of ICI 118,551 20 mg was similar to that of 40 mg and of propranolol 10 mg, but greater than that of atenolol 25 mg. An isoprenaline tachycardia was attenuated by all doses of ICI 118,551 studied. After atropine (0.04 mg/kg) ICI 118,551 20 mg still significantly reduced the effects of isoprenaline suggesting that functional beta 2-adrenoceptors may be present in the human heart. In doses less than 40 mg, ICI 118,551 appears to be a selective and competitive antagonist of beta 2-adrenoceptors in man.

Adrenergic beta-Antagonists↗

PubMed1985

Comparison of the haemodynamic effects of bucindolol, propranolol and pindolol in healthy volunteers.

The effects of single oral doses of bucindolol (50, 100, 200 and 400 mg), pindolol (10 mg), propranolol (160 mg) and placebo on arterial pressure and heart rate in the supine and standing positions and exercise heart rate were compared in 12 healthy male volunteers. Supine heart rate was significantly greater after all four doses of bucindolol and pindolol in comparison to propranolol. Bucindolol had no significant effect on standing heart rate which was significantly reduced by pindolol and propranolol. Bucindolol, pindolol and propranolol significantly reduced an exercise tachycardia for at least 24 h after drug administration. Supine systolic pressure was not affected by any treatment but supine diastolic pressure was significantly reduced by bucindolol (200 and 400 mg) and by pindolol. All doses of bucindolol, propranolol and pindolol significantly reduced standing systolic blood pressure. There was a significant linear trend for reductions in standing systolic blood pressure and increasing doses of bucindolol. Standing diastolic blood pressure was significantly reduced by bucindolol 200 and 400 mg. Faintness and light headedness occurred in 6 of 12 subjects after 200 mg bucindolol and in 8 of 10 subjects after 400 bucindolol. After bucindolol, analysis of plasma samples demonstrated the presence of bucindolol, 5-hydroxy and 6-hydroxy bucindolol and indolyl-t-butylamine. These observations indicate that in man, bucindolol is a beta-adrenoceptor blocking drug with hypotensive activity and probably partial agonist activity. It is unlikely that the hypotensive effects result from blockade of beta-adrenoceptors or from the drug's partial agonist activity.

Adrenergic beta-Antagonists↗

PubMed1984

Differential blockade of alpha-adrenoceptors by indoramin.

The effect of equihypotensive single oral doses of indoramin (mean dose 67 mg), phenoxybenzamine (mean dose 50 mg), hydralazine (mean dose 133 mg) and placebo on arterial pressure and heart rate in the supine and standing position was studied in six normal volunteers. Observations were made before and at 2 and 4 h after drug administration. Plasma noradrenaline (NA) was measured at each time interval in the supine position, and after 4 min of standing. Plasma renin activity (PRA) was measured at each time interval after 30 min in the standing position. The three active drugs reduced systolic arterial pressure in the standing position to a similar extent (indoramin, -24 mm Hg; phenoxybenzamine, -23.4 mm Hg; hydralazine, -30.4 mm Hg). The maximum effect of indoramin and phenoxybenzamine was observed at 4 h, and of hydralazine at 2 h after drug administration. The reductions of arterial pressure in the standing position were accompanied by increases in heart rate, plasma NA and PRA. Small increases were observed after indoramin (heart rate, + 9.2 beats min-1; plasma NA, + 126 pg/ml; PRA, + 0.33 ng angiotensin 1 ml-1 h-1), greater increases after phenoxybenzamine (heart rate, + 20; plasma NA, + 210; PRA, + 0.47), and the greatest increases after hydralazine (heart rate, + 26; plasma NA, + 250; PRA, + 1.16). In the supine position, indoramin and phenoxybenzamine produced no effect on arterial pressure, heart rate or plasma NA. Hydralazine produced small reductions in diastolic pressure, which were accompanied by an increase in heart rate of 25.5 beats min-1 (P less than 0.01 when compared to placebo) and in plasma NA of 223 pg ml-1 (P less than 0.05). Plasma NA, PRA and heart rate increased together and may be regarded as three interdependent indices of sympathetic activity. Indoramin reduced the degree of increase of plasma NA, PRA and heart rate per unit fall in pressure, when compared to phenoxybenzamine and hydralazine. The effect of phenoxybenzamine and hydralazine on the degree of increase was similar. The results are consistent with the hypothesis that indoramin produces selective postsynaptic alpha 1-adrenoceptor blockade in man, and therefore produces relatively less tachycardia and NA increase than does a non-selective alpha-adrenoceptor antagonist (phenoxybenzamine) or an arteriolar vasodilator (hydralazine).

Adolescent↗

PubMed1984

Effect of indoramin, labetalol and alinidine on sympathetic function in normal man.

The effects of single oral doses of indoramin (mean dose 58 mg), abetalol (mean dose 150 mg), alinidine 80 mg and placebo on arterial pressure and heart rate in the supine and standing positions were studied in six normal volunteers. Doses were chosen to give equivalent reductions of arterial pressure in the standing position. Observations were made before and at 2 and 4 h after drug administration. Plasma noradrenaline (NA) was measured at each time interval in the supine position, and after 4 min of standing. Plasma renin activity (PRA) was measured at each time interval after 30 min in the standing position. In the supine position, alinidine produced a significant reduction of systolic arterial pressure from 124.0 +/- 3.0 mm Hg to 104.3 +/- 4.1 mm Hg at 2 h (P less than 0.01) and to 101.7 +/- 2.2 mm Hg at 4 h (P less than 0.01). Diastolic pressure was reduced from 74.7 +/- 2.6 mm Hg to 57.0 +/- 4.6 mm Hg at 4 h (P less than 0.01). Arterial pressure was unchanged after indoramin or labetalol administration. In the supine position, heart rate was unchanged after indoramin, and small reductions were observed after labetalol and alinidine. Indoramin produced a significant increase in plasma NA. A small increase of plasma NA was observed after labetalol, and a small decrease after alinidine. In the standing position, the three active drugs reduced systolic arterial pressure to a similar extent (indoramin, -26.7 mm Hg at 4 h after drug administration; labetalol, -21.3 mm Hg at 2 h; alinidine, -21.7 mm Hg at 4 h).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1983

Trends in peptic ulcer related diseases from 1972 to 1980. Hospital activity analysis data and general practice cimetidine prescribing levels.

Between 1972 and 1980 Hospital Activity Analysis from 5 Northern Ireland Hospitals demonstrated a gradual increase in the number of patients discharged for all diagnoses whilst there was a decline in discharges for peptic ulcer related disease, (duodenal ulcer, gastric ulcer, gastrojejunal ulcer, peptic ulcer site unspecified and hiatal hernia). The mean number of peptic ulcer related disease discharges per year for 1977-80, when cimetidine became generally available, was 10% lower than that of 1972-76, mainly due to a decline in male patient numbers. The mean annual number of male patients with a duodenal ulcer fell significantly by 18% (U = 1, p less than or equal to 0.025) during the 1977-80 period, whereas female discharges decreased by only 4%. Between 1972-76 and 1977-80 the mean annual number of duodenal ulcer perforations decreased significantly by 21% in males but only by 4% in females. Surgery for peptic ulcer related disease was 47% less in 1977-80 period, with significant decreases in duodenal ulcer, gastric ulcer and hiatal hernia procedures. From 1977 to 1980 there was considerable growth in Northern Ireland general practice cimetidine prescribing with 300,000 prescriptions being dispensed over the period. Apart from male duodenal ulcer cases, hospitalisation for peptic ulcer related diseases did not decrease substantially after the introduction of cimetidine but duodenal ulcer perforation and conditions warranting surgery did decline.

Cimetidine↗

PubMed1983

Comparison of the effect of pindolol and propranolol on heart rate after acute and chronic administration.

1 The present study compared the effects in healthy volunteers of the acute and chronic administration of placebo, pindolol and propranolol to see if the partial agonist activity of pindolol was reduced by the beta-adrenoceptor blocking activity of pindolol on chronic administration. 2 Five subjects received in random order for 8 days placebo, propranolol 160 mg and pindolol 10 mg; on days 1 and 8 treatments were given twice at 0 and 2 h. Heart rate in supine position and at end of exercise was recorded before dosing and at 2 and 4 h post-dosing on days 1 and 8. 3 Propranolol and pindolol reduced exercise heart rate to the same extent on days 1 and 8. 4 Propranolol reduced supine heart rate more than pindolol on days 1 and 8 but the difference was only significant on day 8.

Adult↗

PubMed1982

Drug monitoring of surgical patients.

Intensive drug monitoring of surgical patients was carried out on selected wards in five hospitals in the United States, Scotland, and New Zealand from 1977 through 1981. This report describes the methods and some findings from the monitoring of 5,232 such patients. Patients received, on the average, nine drugs on the ward, and adverse reactions were associated with 2.2% of these drug orders. Of the 1,150 drug-attributed adverse reactions, only 62 were considered "major" by the attending physician, and 35 (affecting 20 patients) were termed "life threatening." There were no drug-attributed deaths.

Adolescent↗

PubMed1982

Drug attributed alterations in potassium handling in congestive cardiac failure.

Information from a comprehensive drug surveillance programme has been reviewed to give details of the frequency of drug-related hypo- and hyperkalaemia in a group of 3879 patients admitted to hospital with cardiac failure. Hypokalaemia was commoner in females, was unrelated to blood area concentration on admission and was twice as common amongst recipients of potassium-losing diuretics who did not take potassium supplements than amongst those who received potassium retaining diuretics. By contrast hyperkalaemia was strongly related to blood urea concentration on admission. It was also related to in-hospital diuretic therapy; being thrice as frequent amongst recipients of aldosterone antagonists than amongst those receiving potassium-losing diuretics without additional supplements. Life-threatening hypo- and hyper-kalaemia were rare in this group of patients with heart failure, occurring with approximately equal frequencies of about 2 per 1000 patients treated.

Adult↗

PubMed1982