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Biomedical subjects

T D Lawrie

Publications and source records attributed to T D Lawrie.

At least 55 records · Page 3Linked to original sources
PubMed1977

Cardiovascular effects of a new inotropic agent, U. K. 14275, in patients with coronary heart disease.

1 The chronotropic and inotropic properties of U.K. 14275, a phosphodiesterase inhibitor were assessed in patients with coronary heart disease. 2 Left ventricular function was assessed in eight patients with acute myocardial infarction using the non-invasive measurement of systolic time intervals. 3 Twelve patients with angina pectoris were studied during diagnostic coronary arteriography. Left ventricular function was assessed using a high fidelity catheter tipped transducer in the left ventricle. 4 In both groups of patients U.K. 14275 infused intravenously in doses of 32, 64, 128 and 256 microgram kg-1 bodyweight min-1 enhanced the contractile state of the left ventricle without altering the heart rate.

Coronary Disease↗
PubMed1976

Relationship of plasma uric acid to plasma lipids and lipoproteins in subjects with peripheral vascular disease.

Hyperuricaemia and hyperlipidaemia (elevated fasting plasma cholesterol or triglycerides) were frequently found in 219 males and 63 females with peripheral vascular disease (PVD). The subjects were divided into sexes and the uric acid, cholesterol and triglyceride concentration adjusted for the effects of age and obesity by multiple regression analysis. Followig this no significant relationship was found between uric acid and cholesterol or triglyceride. When the males with PVD were divided into lipoprotein types it was found that those who were normo-lipoproteinaemics or who had type IV hyperlipoproteinaemia (HLP) had a significantly higher mean uric acid level. The other types had a mean uric acid concentration similar to that found in 25 healthy normolipoproteinaemic males. The discrepancy between this result and the lack of correlation between uric acid and triglyceride noted above is presumably due to the complex effects of age and obesity. In the females no significant increase in the mean uric acid concentration was found in any of the lipoprotein groups.

Body Weight↗
PubMed1976

Beta-adrenoreceptor blockade in hypertension.

There is good evidence from many sources that beta-adrenoreceptor blockade is an effective form of therapy in mild, moderate and severe hypertension either alone or in combination with other antihypertensive agents. Although a number os such beta blocking compounds are now available, they appear to have a hypotensive effect of approximately equal magnitude. This hypotensive effect is obtained in both the supine and standing positions thus avoiding postural hypotension. The maximum hypotensive effect may take some time to become apparent. Despite considerable work the mode of action remains uncertain, reduction in cardiac output, resetting of baroreceptors, reduction in plasma renin and a central nervous system effect have been suggested but remain unproved. There is evidence to suggest that these compounds can control, to some degree, the surges in blood pressure resulting from either mental or physical stress. A low incidence of serious side effects has been reported by many workers. Only the long-term use of these compounds in comparison with other antihypertensive agents will determine their place in the management of hypertension.

Adrenergic beta-Antagonists↗
PubMed1976

Low density lipoprotein metabolism in a family of familial hypercholesterolemic patients.

A low-density lipoprotein turnover study was performed on six heteroxygous familial hypercholesterolemic subjects and five control subjects. The diagnosis of the condition was clear-cut on biochemical, clinical, and genetic grounds. Kinetic analysis of the plasma decay curves gave the following mean values: (1) The plasma concentration of low density lipoprotein apoprotein (apoLDL) in the affected subjects was 247 mg/dl, a 2.5-fold increase over control values (98 mg/dl). (2) The calculated fractional catabolic rate of the intravascular apoLDL pool in the dyslipo-proteniemics was reduced with respect to control data (16.4%/day versus 31.2%/day), and the half-life of the apolipoprotein was correspondingly increased (6.07 days versus 3.63 days). (3) The absolute catabolic rate of the apoLDL was 15.6 mg/kg/day in contrast to the lower value of 11.6 mg/kg/day in the control group. (4) A strong negative correlation was observed between the plasma apoLDL concentration and the fractional catabolic rate (r = 0.96). We conclude from our data that increased apoLDL synthesis coupled with a defective or saturated catabolic mechanism is implicated in the pathogenesis of familial hypercholesterolemia.

Adult↗
PubMed1976

Lipoprotein levels in apparently healthy men and women in the west of Scotland.

Lipoprotein typing was undertaken in apparently healthy women (419) and men (103) in whom measurements of fasting total cholesterol, triglycerides, and cholesterol content of the major lipoprotein fractions were made. In the female group (30 to 59 years) there was a significant rise in total cholesterol, low density lipoprotein (LDL) cholesterol, and triglycerides with age. Using total cholesterol and triglyceride levels for classification, type II hyperlipoproteinaemia was present in 1 per cent and type IV in 6-7 per cent. When LDL cholesterol levels were also considered, type II occurred in 9-8 per cent ( 8-4% type IIA and 1-4% type IIB). In the male group ( 40 to 59 years) there was no increase in cholesterol or triglyceride levels with age: II per cent had type IV hyperlipoproteinaemia and none had a type II abnormality. When LDL cholesterol levels were also considered, type II occurred in 3 per cent ( 2% type IIA and 1% IIB). The apparent increase in LDL cholesterol frequency of type IIA abnormality in women could be merely the consequence of arbitrary selection of upper limits of normality for LDL cholesterol, but may signify improved detection of a high risk group.

Adult↗
PubMed1976

Serial 3 orthogonal lead electrocardiographic abnormalities after pulmonary embolism. Computer assisted study.

The 3 orthogonal lead electrocardiogram has been evaluated with computer assisted interpretation in 20 patients with acute pulmonary embolism confirmed by pulmonary angiography. Initial 3-lead electrocardiographic abnormalities were found to be at least as helpful as the 12-lead electrocardiogram in supporting the clinical diagnosis. In addition, however, sequential changes in both the maximum QRS and T vector orientations in frontal and transverse planes were more often apparent than any sequential changes in the 12-lead electrocardiogram. While no specific 3 lead electrocardiographic criterion for pulmonary embolism could be determined, this technique was more helpful than conventional methods in following serial electrocardiographic changes in patients with this condition.

Adult↗
PubMed1976

Comparison of 12-lead and computer-analysed 3 orthogonal lead electocardiogram in coronary artery disease.

The computer-analysed 3 orthogonal lead system ("3-lead ECG") provides a rapid and consistent interpretation of the electrocardiogram. In 102 patients undergoing selective coronary arteriography, the ability of such a system to predict the presence of absence of coronary artery disease and the site of myocardial ischaemia was compared with that of the conventional scalar electrocardiogram interpreted by cardiologists ("12-lead ECG"). Each system predicted the site of myocardial ischaemia with equal accuracy. The 3-lead ECG was a more sensitive index (3-lead ECG sensitivity=77%; 12-lead ECG sensitivity=70%) but less specific (3-lead ECG specificity=74%; 12-lead ECG specificity=78%). In coronary artery disease, the predictive "index of merit" for the 3-lead ECG was 0-51, compared with 0-48 for the 12-lead ECG. These results provide further justification for the routine use of the 3 orthogonal lead electrocardiogram.

Adult↗
PubMed1976

Indications for beta-adrenoceptor blocking drugs in hypertension.

The past 10 years have firmly established the role of beta-adrenoceptor blocking agents in the treatment of hypertension. They have been shown to lower systolic and diastolic blood pressure in the lying and standing position in mild, moderate and severe hypertension. Precise indications for beta-blockade have not yet been completely defined. Some authorities regard them as the drug of first choice in the management of most grades of idiopathic hypertension. There are in addition certain situations where beta-blockade seems especially suitable. These include the presence of associated coronary heart disease manifest either as angina pectoris or dysrhythmia. These agents can be introduced when side effects from other drugs are severe or intolerable and are valuable in the management of hypertensive young males since beta-blocking drugs do not interfere with sexual function. Compared with normotensive subjects 'stress' has been shown to produce excessive rise of blood pressure in those with labile or sustained idiopathic hypertension. After therapy with beta-blocking agents the rise in blood pressure after 'stress' is reduced. If labile and/or mild hypertension are the precursors of subsequently more severe sustained hypertension, then long term beta-blockade may help to control this response.

Adrenergic beta-Antagonists↗