Wound colonisation following cardiac surgery. Reduction by adjuvant use of preincisional, presternal antibiotic infiltration: a double blind prospective randomised study

In a double blind, prospective, randomised study of 100 patients undergoing elective cardiac surgery, a significant (p less than 0.01) reduction in wound colonisation, defined as positive culture of any wound discharge irrespective of wound appearance, occurred in those receiving preincisional presternal antibiotic infiltration (2%) as compared to a control group who received a similar volume of normal saline by the same route (24%). Both groups received, in addition, the same conventional intravenous regimen of broad spectrum antibiotic. A comparable concurrent group of patients, not entered into the study, demonstrated a wound colonisation rate similar to the trial control group (22%), thus excluding an adverse bias from the control saline infiltration. Analysis of control cases demonstrated a significant (p less than 0.001) discriminant effect in the degree of preoperative haemodilution with haematocrit falling on bypass by a mean of 25% in those who developed wound colonisation as compared to 13% in those who did not.     

Policies for managing hypertensive patients: a survey of the opinions of British specialists

In September 1988 medically-qualified members of the British Hypertension Society were asked to complete anonymously a questionnaire relating to their views on the management of hypertensive patients. Of 149 questionnaires posted, 90 were returned (60%). There was general agreement that non-pharmacological measures, particularly weight loss and alcohol restriction, are effective treatments. However, there was wide variation in the minimum level of blood pressure considered to warrant drug treatment and little consensus regarding measurement policies or target blood pressures. The drugs of first choice were beta-blockers (54% in men, 35% in women) and thiazide diuretics (28% in men and 47% in women), and they were also the most frequent second choices with 54% of respondents advocating 'stepped-care' based on these drugs. The maximum age at which respondents would be prepared to introduce antihypertensive drugs varied widely although 63% considered that thiazide diuretics are first choice in the elderly. These findings demonstrate a broad range of opinion on the management of hypertension among British specialists, and suggest a continuing need for large clinical trials.     

Postpartum depression in adolescent mothers: an integrative review of the literature.

Research on adolescent mothers has revealed increasing rates of depressive symptoms in the postpartum period. This review integrated 12 research-based articles to provide a better understanding of depression among adolescent mothers in the first year postpartum. The results revealed that more family conflict, fewer social supports, and low self-esteem all were associated with increased rates of depressive symptoms in adolescent mothers during the first postpartum year. To prevent adverse outcomes associated with depression, it is important that nurse practitioners working with these families screen adolescent mothers for depression and refer them for treatment as needed.     

Discriminative stimulus properties of beta-phenylethylamine, deuterated beta-phenylethylamine, phenylethanolamine and some metabolites of phenylethylamine in rodents

The discriminative stimulus (cue) properties of phenylethylamine (PEA) were analysed in rodents in a conventional two lever FR10 operant drug discrimination task. Rats trained to discriminate phenylethylamine at 30 mg/kg showed complete dose-related generalization to PEA and to two potential PEA metabolites: phenylethanolamine (PEOH) and N-Methyl PEA (NMPEA). Only partial (50%) generalization was seen with N-Methylphenylethanolamine (NMPEOH), another potential PEA metabolite. The specificity of PEA's action as a discriminative stimulus was demonstrated by the finding that fenfluramine, a substituted phenylethylamine, failed to generalize to PEA even at high doses with marked behavioural effects which are known to have discriminative stimulus properties themselves. These data suggest that NMPEA and PEOH may be functionally important active metabolites of PEA, particularly if the major pathway of PEA metabolism to phenylacetic acid under the influence of MAO Type B is for any reason impaired. A long acting deuterium substituted form of PEA (alpha, alpha, d2 PEA), which is resistant to metabolism by MAO, produced complete dose-related generalization to the PEA cue but was more potent than PEA, due presumably to its resistance to metabolism by MAO. Deuterated PEA may therefore be a useful agent to use in future studies of the PEA cue, because the discriminability of PEA itself appears to be low due to its very rapid metabolism in vivo.     

The cytoarchitectonic boundaries of the monocular and binocular areas of the rat primary visual cortex

We describe the cytoarchitectonic characteristics of the monocular (Oc1M) and the binocular (Oc1B) areas of the rat visual cortex and their boundaries in Nissl-stained sections. This formulation, which draws upon the computer image analysis of these areas by Zilles et al. (J. Comp. Neurol., 226 (1984) 391–402), can aid in the delineation of Oc1M from Oc1B in quantitative studies requiring a volumetric analysis of both subfields.     

Evolution of structural changes leading to haemolysis in human erythrocytes treated with SK&F 95018, an antihypertensive compound with combined vasodilator and β-adrenoceptor antagonist properties

SK&F 95018 is an antihypertensive compound with combined vasodilator and β-adrenoceptor antagonist properties, which, when given to dogs by intravenous infusion, rapidly produced symptoms of intravascular haemolysis. The haemolytic potency of SK&F 95018 was confirmed in vitro using human erythrocytes, was concentration dependent and was associated with dose-specific morphological changes as determined by scanning and transmission electron microscopy. Treatment of washed human erythrocytes with 0.5 mm-SK&F 95018 for up to 30 min resulted in gradual transformation from the biconcave discocyte to stomatocyte forms. Stomatocytes developed more rapidly on exposure to 2 mm-SK&F 95018, exhibited unilateral, multifocal invaginations by 2 min and evolved into spherocytic erythrocytes showing many membrane protuberances and invaginations. At the highest treatment level (10 mm) the crenated erythrocytes seen at time 0 transformed rapidly into spherocytes with many membrane-bound, surface projections that were retained in erythrocyte membrane ‘ghosts’. The membrane-active properties of SK&F 95018 were investigated in a phospholipid-membrane model (an aqueous dispersion of side-chain perdeuterated dipalmitoylphosphatidylcholine) by proton and deuterium nuclear magnetic resonance spectroscopy. The results suggest that SK&F 95018, with its molecular dual polarity, inserts into and effectively disrupts the intergrity of biological membranes by micellar reorganization of the bilayer plasmalemma. The slow change in shape from discocyte to stomatospherocyte at the lowest concentration (without the development of membrane-associated protuberances) suggests a disruptive effect on the erythrocyte osmotic balance by gradual cumulative drug insertion into the membrane. At higher concentrations this initial effect (leading to cell swelling) appears to proceed contemporaneously with micellar membrane reordering, producing membrane protuberances.     

Psychometric differentiation of dementia. Replication and extension of the findings of Storandt and coworkers

In a previous investigation by Storandt and coworkers, a brief battery of four neuropsychological tests was found to accurately distinguish a sample of patients with senile dementia of the Alzheimer type (SDAT) from normal elderly persons. The present study examined the value of these tests in the distinction between SDAT and dementias of other etiologies. Our results replicated those of Storandt and coworkers in that these tests did distinguish normal persons from patients with both SDAT and other dementias. These tests, however, did not accurately differentiate among the dementias. These results indicate that assessment batteries utilizing additional procedures to supplement cognitive testing are indicated to more accurately discriminate among the dementias.     

Haemodynamic and humoral effects of oral perindopril, an angiotensin converting enzyme inhibitor, in man.

The tolerance to and dynamic effects of 1 week's oral treatment with the angiotensin converting enzyme inhibitor, perindopril, were assessed in a placebo controlled, parallel group study in 36 normotensive males. The daily dose of perindopril was 1, 2, 4, 8 or 16 mg. The drug was well tolerated and produced no change in routine haematology or serum biochemistry tests. Dose related inhibition of plasma angiotensin converting enzyme was observed. Perindopril 16 mg produced 90% inhibition 4 h after dosing and 60% after 24 h. A dose related rise in plasma renin activity followed doses of 4 mg and over. The renin remained above the normal range for 24 h. Perindopril caused a modest lowering of plasma aldosterone levels but had no effect on plasma adrenaline or noradrenaline levels. Standing diastolic blood pressure was lowered, particularly with 16 mg daily of perindopril but only a slight rise in heart rate occurred. Perindopril appears to be a well tolerated inhibitor of plasma angiotensin converting enzyme, with predictable effects on the renin angiotensin system and blood pressure. An appropriate dose range for further study would appear to be 4 to 16 mg daily.