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Biomedical subjects

D MacLean

Publications and source records attributed to D MacLean.

9 recordsLinked to original sources
PubMed1991

Effects of xamoterol in acute myocardial infarction: blood pressure, heart rate, arrhythmias and early clinical course.

Xamoterol is a novel partial agonist of beta 1 adrenoceptors that reduces myocardial ischaemia and improves ventricular function in patients with mild to moderate heart failure. In a double blind, randomised, placebo controlled study, the effects of xamoterol given in a dose of 200 mg twice daily were studied in 51 consecutive patients with acute myocardial infarction, including 17 receiving diuretics for left ventricular failure. Treatment was started on the third day of admission and continued for 7 days. Blood pressure was recorded at 0900 daily, and 24 hour ambulatory electrocardiogram monitoring was commenced at this time on days 1 (pre-treatment), 4, 6 and 9 of admission. Additional drug therapy was recorded daily throughout the study. One patient died prior to randomisation and three were withdrawn (1 placebo, 2 xamoterol) with ventricular arrhythmias and/or disturbances of conduction. Compared to placebo, xamoterol had no effect on the rate of ventricular premature beats or ventricular tachycardia. Xamoterol increased nocturnal heart rate (0000-0600 hrs 79 +/- 2; placebo 72 +/- beats/min; P less than 0.03) but did not change blood pressure. Three patients receiving xamoterol, and 7 on placebo, required new (after randomisation) antianginal therapy. One patient treated with placebo developed new heart failure. These results show that xamoterol can be administered safely to selected patients following myocardial infarction, including those treated for mild heart failure.

Adrenergic beta-Agonists↗
PubMed1990

Neuroendocrine changes post myocardial infarction: effects of xamoterol.

This study reports the effects of the new beta 1 adrenoceptor partial agonist, xamoterol, on neuroendocrine activity after acute myocardial infarction (AMI). Fifty-one consecutive patients with AMI were randomized to treatment with xamoterol, 200 mg twice a day, or placebo; patients were also stratified as to whether or not diuretic therapy was given for left ventricular dysfunction. Noradrenaline, plasma renin activity (PRA), and atrial natriuretic factor (ANF) were measured over a 10-day period. Noradrenaline concentrations are higher (p less than 0.05) in patients treated with diuretics at the time of admission and fell over the subsequent 10 days (p less than 0.01). Treatment with xamoterol did not affect this noradrenaline response to myocardial infarction. PRA was also significantly higher in the patients treated with diuretics, and there was a nonsignificant trend for xamoterol to blunt the PRA response in these patients. There was no difference in ANF levels between those patients who were treated with diuretics and those who were not; xamoterol did not affect ANF. Thus xamoterol does not further elevate noradrenaline levels as do conventional beta blockers, and it does not activate the renin-angiotensin system as do potent nonselective beta agonists. Furthermore, xamoterol does not increase ANF levels, probably because it is not negatively inotropic. We conclude that xamoterol does not cause deleterious neuroendocrine changes in patients with AMI even in those treated for heart failure.

Adrenergic beta-Agonists↗
PubMed1990

Baseline assessment. Report of a company wide risk factor survey.

CVD accounts for the highest rates of morbidity and mortality among the general population. Unhealthy lifestyle practices are largely responsible for this occurrence. Risk factor prevalence of smoking, uncontrolled high blood pressure, and high serum cholesterol levels contribute to the likelihood of developing CVD. Two or more of these risk factors can place individuals at higher risk of developing CVD. Completing a heart health survey of risk factor prevalence among a working population will give occupational health professionals a basis on which to set goals and objectives for effective CVD intervention programs.

Adolescent↗
PubMed1989

Maximum expiratory airflow during chest physiotherapy on ventilated patients before and after the application of an abdominal binder.

Chest physiotherapy using a manual ventilation technique was carried out on 9 intubated patients. One patient was studied on two occasions. The maximum expiratory flow rate (MEFR) was recorded during: (A) manual ventilation without physiotherapy, (B) manual ventilation with chest compression, (C) manual ventilation and chest compression, after application of the abdominal binder. Statistical analysis was carried out to allow for differences in tidal volume (Vt). Chest physiotherapy increased the mean MEFR and application of an abdominal binder (together with physiotherapy) caused a further increase in MEFR. The mean MEFR (assuming a common Vt of 1360 ml) in each group was; (A) = 73.3 l min-1, (B) = 103.9 l min-1, (C) = 113.93 l min-1.

Abdomen↗
PubMed1989

Persistence of pertussis in an immunized population: results of the Nova Scotia Enhanced Pertussis Surveillance Program.

An enhanced pertussis surveillance and laboratory diagnosis program was initiated in the Halifax metropolitan area of Nova Scotia to better delineate the epidemiology of pertussis. During the 28 months of the study, 526 cases of pertussis were identified (overall yearly incidence: 74 cases per 100,000 population). Laboratory confirmation was obtained in 168 (32%) cases, including 111 (21%) by culture. Peak incidence occurred among children 2 to 5 years of age; the highest morbidity rate was seen in children less than 1 year of age. Hospitalization was required for 22 (4.2%) patients; 14 (64%) of those hospitalized were less than 1 year of age. Most (91%) patients had received at least three doses of pertussis vaccine; vaccine efficacy was estimated at 45%. The surveillance program demonstrated that the incidence of pertussis in Nova Scotia, although among the highest in North America, is still underestimated. A ninefold increase in cases was identified over the comparable period of the previous year, largely because patients meeting clinical criteria were reported. By supplementing culture techniques with immunofluorescent staining and serologic methods, we increased the rate of laboratory confirmation from 17% to 65%, suggesting that strict clinical criteria accurately reflect accurately reflect incidence. We conclude that pertussis remains a significant health problem in Nova Scotia, despite nearly universal vaccination.

Child, Preschool↗
PubMed1975

Genetics.

Explore the source record for details and available documents.

Chromosome Aberrations↗