Effect of morphine on splanchnic blood flow. Splanchnic blood flow was measured by the constant infusion of indocyanine green given before and after morphine 0.2 mg/kg (maximum 15 mg) intravenously in 13 patients. Splanchnic blood flow increased from 1012 +/- 98 ml/min to 1200 +/- 118 ml/min after the administration of morphine, a 19 per cent increase (P less than 0.025). Splanchnic vascular resistance decreased from 0.094 +/- 0.010 to 0.081 +/- 0.010 mmHg min/ml, a 16 per cent decrease (P less than 0.001). There was no significant change between baseline and post-morphine values in systemic arterial pressure (92.2 +/- 3.8 and 89.0 +/- 2.9 mmHg), hepatic vein wedge pressure (7.1 +/- 1.0 and 7.8 +/- 0.6 mmHg), or right atrial mean pressure (4.5 +/- 0.6 and 4.3 +/- 0.7 mmHg). This study shows that morphine induced significant splanchnic arteriolar dilatation.


Diazoxide in treatment of primary pulmonary hypertension. Three patients with primary pulmonary hypertension and one man with suspected thromboembolic pulmonary hypertension were given up to 300 mg diazoxide by injection into the pulmonary artery. The three patients with primary pulmonary hypertension responded with a fall in total pulmonary resistance and a rise in cardiac output. The patient with suspected thromboembolic pulmonary hypertension did not respond. Haemodynamic and clinical improvement was maintained by oral diazoxide in two of the responders, and in one the prognosis appeared to be greatly improved.


Left atrial myxoma with aortic regurgitation. A 59-year-old woman with a left atrial myxoma was shown to have moderate aortic regurgitation. At operation for removal of the myxoma it was found to be attached to the atrial septum close to the aortic root. It is suggested that the aortic regurgitation was caused by distortion of the aortic root caused by traction upon it from the myxoma as it moved downward into the left ventricle in diastole. Observations are made on the echocardiographic findings which helped in the diagnosis of the left atrial myxoma.


Tricuspid valve excision without replacement in a case of endocarditis secondary to drug abuse. A patient is presented in whom urgent surgical intervention was necessary to alleviate the consequences of tricuspid valve endocarditis. Six months after operation she remains well, without a valve prosthesis.


A case of surgically corrected Wolff-Parkinson-White syndrome. Clinical and histological data. A case of type B Wolff-Parkinson-White syndrome, with intractable atrial fibrillation, underwent surgical division of a right-sided accessory atrioventricular bundle of Kent. Pre-excitation and complicating tachyarrhythmias were henceforth abolished for 6 weeks, when the patient died of infective endocarditis. Histological examination showed a divided Kent's accessory atrioventricular pathway and apparently functionless James and Mahaim fibres.


Clinical experience with transvenous atrial pacing. Twelve patients were paced with a transvenous J-shaped bipolar electrode positioned in the right atrial appendage. All had chronic sinoatrial dysfunction and 5 had paroxysmal atrial arrhythmia: 2 had recent myocardial infarction, 1 angina decubitus, and 1 ventricular pre-excitation. Atrioventricular sequential pacing was employed in this last patient and this mode of pacing was substituted for atrial pacing in one other. The remaining 10 patients were paced from the atrium only. Electrode displacement occurred in 2 patients and 2 others had a rise in pacing threshold. After repositioning the electrode or substituting a more powerful pacemaker, sustained atrial capture was achieved in 3 of these 4. Sensing of spontaneous P waves was present constantly in 4 and variably in 3 of 9 patients. Symptomatic improvement was obtained in 10 patients. A bipolar pacemaker with a variable output voltage and a relatively high demand sensitivity is optimal for atrial pacing. Measurements of intra-atrial voltage with various electrode configurations in 7 patients suggest that atrial sensing may more often be achieved when the reference electrode is situated in the upper part of the right atrium than when it is close to the electrode tip in the atrial appendage.


Long-term haemodynamic evaluation of aortic pericardial xenograft. Haemodynamic studies were performed in 30 patients at a mean interval of 43.4 (range 27 to 59) months after aortic valve replacements with pericardial xenografts. Five valve sizes--19, 21, 23, 25, and 27 mm annulus diameter--were used. Of these 30 patients, 16 had preoperative haemodynamic investigations. Comparison of the pre- and postoperative data showed a marginal but significant increase in cardiac output (P less than 0.05). There was a significant reduction in the pulmonary wedge and left ventricular end-diastolic pressures at rest and on exercise (P less than 0.05 and P less than 0.01). At the postoperative study the mean peak systolic gradient was 8.3 mmHg at rest and 12.3 mmHg on exercise in patients with the smallest xenograft inserted (19 mm) and decreased with each corresponding increase in graft size, so that across the 27 mm graft it was hardly measurable. The calculated xenograft surface area ranged from 1.1 to 2.1 cm2 at rest and 1.3 to 2.4 cm2 during exercise. Aortic root angiography showed competent valves in all 30 patients, but a grade 1 to 2 perivalvular leak was shown in 8 patients. This long-term study has indicated significant circulatory improvement and very small transvalvular gradients in patients with aortic pericardial xenografts.


Results after mitral valve replacement with cloth-covered Starr-Edwards prostheses (models 6300, 6310/6320, and 6400). The actuarial survival and thromboembolic rates for the three types of cloth-covered Starr-Edwards mitral prostheses, models 6300, 6310/6320, and 6400 followed 6, 5, and 2 years, respectively, were not significantly different throughout the years they were followed. The combined cumulative survival and thromboembolic proportion at 5 years for these prostheses were 71 and 66 per cent, respectively. The thromboembolic rates were not different in the following two groups: (a) 238 patients receiving anticoagulants, and (b) 52 patients who had discontinued or who were not receiving anticoagulants. Four patients thrombosed their mitral prostheses. Another 8 per cent had class 3 symptoms after operation, which were attributed to myopathic or restrictive left ventricular dysfunction or other valvular disease.


Two monitored cases of sudden death outside hospital. Two patients known to have coronary artery disease died suddenly outdoors while active. Neither had symptoms or signs of acute myocardial infarction. They were being monitored by continuous tape recording of the electrocardiogram at the time of death. In one patient the cause of death was cardiac arrest, preceded by bigeminy and multiform ventricular ectopic beats, in the other ventricular fibrillation preceded by atrial fibrillation, multiform ventricular ectopic beats, and ST depression. These observations are added to the limited reported cases in which the mechanism leading to sudden death outside the hospital is recorded.


Predictability of sudden death from resting electrocardiogram. Effect of previous manifestations of coronary heart disease. The sudden death rate from coronary heart disease over a mean period of 4 years was related to the electrocardiographic findings in 3 groups of subjects, survivors of myocardial infarction, employed men, and employed men with no symptoms or history of coronary disease. Within each group the sudden death rate correlated with the number of electrocardiographic findings, particularly Q, ST, and T wave items. However, between groups there were large differences in sudden death rates in subjects with the same findings. These were greatest in the case of ventricular conduction disturbances and disturbances of rhythm and rate which appeared to be benign in those free of symptoms but ominous after infarction. Findings predictive of sudden death were also predictive of non-sudden coronary deaths. It is concluded that the electrocardiogram is only one of several aids to the diagnosis and assessment of severity of disease and not a substitute. Prognoses derived from clinical case series are inappropriate to symptomless individuals in whom isolated electrocardiographic findings denote little increase in risk.


Prevalence and prognosis of electrocardiographic findings in middle-aged men. A screening examination including an electrocardiogram (limb leads only) coded by the Minnesota Code, using rigorous quality control was done on 18 403 male civil servants aged 40 to 64. The association of the findings with coronary heart disease has been tested in relation to age trends, symptomatic history, and coronary heart disease mortality rates in the ensuing five years. The results were positive for Q waves, left axis deviation, ST depression, and T wave changes (including minor T wave items as an isolated finding), ventricular conduction defects, and atrial fibrillation; but they were generally unimpressive for increased R amplitude and for lengthening or shortening of the PR interval, QT interval duration, premature beats, and extremes of heart rate. The prognosis of specific electrocardiographic findings discovered at screening is quite different from when they arise in clinical practice. Among the 6 per cent of men in this study with patterns suggesting ischaemia, the subsequent coronary heart disease mortality was little more than 1 per cent per year; and among those who were symptom free it was even less.


Study of untreated hypertensive subjects by means of continuous intra-arterial blood pressure recordings. Continuous recording of intra-arterial blood pressure and electrocardiograms has been performed in 41 ambulant untreated essential hypertensive subjects for periods up to 48 hours. Statistical analysis of the results has revealed: (1) A group of patients who developed a persistent tachycardia during the day. This response was not observed in a control population free of overt cardiovascular disease. (2) Three different haemodynamic responses to day-time activities suggesting different mechanisms for the production of high blood pressures. No normal controls are available for these changes. (3) No differences in responses between patients defined as 'labile' and 'fixed' hypertensives.


Existence of automaticity in anomalous bundle of Wolff-Parkinson-White syndrome. Escape beats probably arising from the anomalous bundle were documented in 2 patients with the Wolff-Parkinson-White (WPW) syndrome. A third patient, in whom complete AV block developed both in the anomalous bundle and the normal pathway, showed the occurrence of escape beats (an escape-bigeminy pattern), as well as a regular idioventricular rhythm arising from the anomalous bundle. Phase 4 block in the anomalous bundle occurred in 7 other patients, in 4 of them spontaneously and in 3 only after the administration of ajmaline or amiodarone. Only 4 of 14 fully investigated patients (out of a total number of 23) showed absence of both escape beats and phase 4 block. The escape beats were considered as direct evidence, and the phase 4 block as indirect evidence, for the existence of automaticity in the anomalous bundle. Such evidence supports the view that the anomalous bundle, like the His bundle-branch system, may be composed of specialised tissue endowed with the property of automaticity.


Distal type of aortopulmonary window. Report of 4 cases. We have studied 14 patients with aortopulmonary window (10 male and 4 female, age range 1 month to 41 years). Four of these had a distal defect with characteristic haemodynamic and angiographic features. Aortopulmonary window may be classified into 3 types: type I (proximal) defects occur in the proximal part of aortopulmonary septum; type II (distal) defects occur in the distal part of the aortopulmonary septum adjacent to the right pulmonary artery; the type III defect is a combination of types I and II. In type I, injection of contrast media into the aortic root opacifies the main pulmonary trunk and then both pulmonary arteries. In type II, the right pulmonary artery is preferentially opacified simulating the finding of right pulmonary artery arising from the ascending aorta. In one case of type II, injection into the right ventricle showed preferential flow to the left pulmonary artery, because of the large shunt of unopacified blood into the right pulmonary artery, but in both types I and II the left and right pulmonary arteries are usually opacified simultaneously after injection into the main pulmonary trunk. In type I either transaortic or transpulmonary closure is the appropriate surgical procedure. In types II and III, the transaortic approach provides better exposure and facilitates the operative repair.


Obstruction of right ventricular outflow tract by solitary ovarian metastasis. We report a case in whom there was right ventricular outflow tract obstruction by a solitary metastatic deposit from an ovarian primary. The patient presented with signs of right ventricular overload and the outflow tract obstruction was recognised at cardiac catheterisation, but the final diagnosis was only revealed at necropsy.


Red cell survival after aortic valve replacement with Björk-Shiley prosthesis in presence of sickle-cell trait. A case of aortic valve replacement with a Björk-Shiley disc prosthesis in a patient with sickle-cell trait is presented. Six months after operation red cell survival was not significantly reduced. On theoretical and clinical grounds it is concluded that the presence of sickle-cell trait does not contribute to late postoperative haemolysis after heart valve replacement.


Acid-base balance and neostigmine antagonism of pancuronium neuromuscular blockade. In 40 cases anesthetized with chloralose and urethane, pancuronium was infused i.v. at a constant rate to produce and maintain 90% depression twitch tension of the anterior tibialis muscle following supramaximal stimulation of the peroneal nerve. Neither respiratory alkalosis nor metabolic acidosis influenced the infusion rate required to produce 90% depression of twitch tension or antagonism of this depression yb neotigmine. Respiratory acidosis (pH 7.15; PaCO2 10 kPa) did not alter the required infusion rate but did prevent complete antagonism by neostigmine. Metabolic alkalosis (pH 7.65; PaCO2 4.8 kPa) reduced both the required infusion rate and prevented complete restoration of twitch tension by neostigmine. The duration of neostigmine antagonism was shortened by metabolic alkalosis. We conclude that respiratory acidosis and metabolic alkalosis prevent antagonism of pancuronium by neostigmine.


The uptake and elimination of chloroform in man. The rate of alveolar uptake of chloroform was studied in 16 patients during general anaesthesia. Eight patients breathed spontaneously and in eight the lungs were ventilated. Elimination was studied after 30 min and 65 min of exposure to the anaesthetic. The arterial and venous blood concentrations of chloroform plotted against time during the early phase of equilibration showed that the initial uptake of chloroform was rapid, approaching a plateau after 40-50 min. In patients breathing spontaneously the arterial concentration of chloroform, which averaged 17.28 +/- 4.1 mg dl-1, did not exceed 25% equilibration with the inspired concentration, whereas under controlled ventilation with 1% chloroform the mean concentration was 10.14 +/- 3.30 mg dl-1, which amounted to an equilibration of approximately 41%. The elimination of chloroform from the body was rapid, so that recovery was not prolonged.


Pulmonary shunting and lung volume during hypotension induced with trimetaphan. In 10 dogs anaesthetized with pentobarbitone mean Pa02 decreased from the control value of 13.5 kPa to 10.2 kPa, cardiac output decreased by 33%, and right-to-left shunt doubled during hypotension induced with trimetaphan. There was no signficant change in functional residual capacity during the period of hypotension or recovery. The hypoxaemia resulted from an increase in ventilation/perfusion inequality, with a decrease in arterial saturation consequent upon a decrease in cardiac output with a constant shunt. During the recovery period, right-to-left shunting remained greater than the values obtained before induction of hypotension.


A preliminary investigation of the renal and hepatic excretion of gallamine triethiodide in man. The fate of gallamine triethiodide has been investigated in patients undergoing cholecystectomy with choledochostomy (group I), pelvic operations (group II) and orthopaedic operations (group III). Following a single i.v. injection of gallamine 2.5 mg kg(-1) the disappearance of the drug from the serum occurred in three phases with half-lives of less than 5, 30, 138 min, less than 5, 39, 141 and less than 5, 48, 144 min in the respective groups. Twenty-four hours after injection the renal excretion of the unchanged drug was 53% (15-100%) of the administered dose in group I, 67% (40-90%) in group II and 95% (89-100%) in group III. The biliary excretion of gallamine appeared to be negligible in man. The relationship between renal excretion and duration of action of gallamine, and the influence of some intraoperative factors on drug disposition, are discussed.


Effects of tracheal intubation on intracranial pressure following induction of anaesthesia with thiopentone or althesin in patients undergoing neurosurgery. Intracranial pressure (i.c.p.) and mean arterial pressure (m.a.p.) were studied in 20 patients during the induction of anaesthesia for craniotomy. Tubocurarine was administered as the muscle relaxant and either thiopentone or Althesin for the induction of anaesthesia. No significant differences were found in the i.c.p. changes with induction, intubation or pharyngeal packing, between the thiopentone and the Althesin groups. Except for two patients (one in each group) the increases in i.c.p. associated with intubation were small. In these two patients moderate increases from normal values to 28 and 37 mm Hg were recorded, but in one of these patients coughing and straining followed intubation. Marked decreases in m.a.p. were noted in both groups, but the recovery of m.a.p. was significantly more rapid in the Althesin group. Only two patients had i.c.p. values greater than 20 mm Hg before operation and in neither did i.c.p. increase above control values during induction and intubation. Packing the pharynx produced minimal changes in i.c.p. in all patients.


Effect of undernutrition on uptake and distribution of i.v. anaesthetic agents. A study in mice. The uptake and distribution of two i.v. anaesthetics agents, thiopentone and Althesin, were studied in mice with normal and subnormal nutritional states. The results show that, following the administration of thiopentone, the induction time was signficantly shorter, and that the sleeping time was significantly longer following the administration of Althesin and thiopentone in mice that have low net protein utilization, and decreased total and dry body mass. The increase in the sleeping time in these undernourished mice was 2.2 times greater for Althesin and 4.0 times greater for thiopentone when compared with well-nourished mice.


Intra-ocular pressure changes during halothane and enflurance anaesthesia. We have measured intra-ocular pressure (i.o.p.) in 20 patients anaesthetized with halothane or enflurance (0.6 MAC in oxygen) for repair of trauma to the eye. The changes in i.o.p. with halothane 0.5% were unpredictable, whereas enflurance 1% reduced intra-ocular tension consistently in all the patients studied. Enflurane is recommended as a possible alternative anaesthetic for surgery on the open eye.


Haemodynamic studies during induction of anaesthesia for open-heart surgery using diazepam and ketamine. In 14 patients undergoing open-heart operations the haemodynamic effects of diazepam 0.4 mgkg(-1) followed by ketamine 2 mg kg(-1) were studied. In eight patients undergoing coronary bypass surgery, the mean arterial pressure decreased significantly after diazepam from 90.3 +/-7.4 (SEM) to 78.0 +/-5.0 mm Hg (P less than 0.05). However, no changes occurred in six patients undergoing valve replacement. The subsequent administration of ketamine produced no significant changes in mean arterial pressure. No signfiicant change in heart rate occurred in any patient at any time during the period of study. No patient reported unpleasant emergence reactions after operation.


Postoperative analgesia following brachial plexus block. The time from the end of surgery to the administration of the first post-operative analgesic has been measured in 86 patients following brachial plexus block with bupivacaine, lignocaine, nepivacaine or prilocaine. A signficant increase in time occurred with bupivacaine; the combination of regional and general anesthesia significantly increased the time when compared with general anaesthesia in the same patient. In children, the use of regional anaesthesia almost removed the need for analgesia after surgery.


Effects of 4-aminopyridine in Eaton Lambert Syndrome. The effects of 4-aminopyridine (a non-anticholinesterase antagonist of curare-like agents) on the evoked muscle action potentials (EMAP) in a patient with Eaton Lambert Syndrome are reported. On two separate occasions the i.v. administration of 0.31 mg kg(-1) and 0.62 mg kg(-1) was followed by a 300% increase of EMAP for about 2 h without serious side-effects.


Hyperpyrexia of uncertain origin.

Hyperpyrexia of uncertain origin. Hyperpyrexia occurring in a 27-year-old woman undergoing eye surgery is described. The cause, although open to doubt, appeared to be a thyroid storm.


Misplacement of nasogastric tubes and oesophageal monitoring devices. Accidental invasion of the trachea past an inflated cuff may occur more easily when endotracheal tubes with soft, low pressure cuffs are used. A new, simple and safe technique for blind oesophageal intubation is outlined. Two cases of accidental invasion of the trachea by oesophageal tubes are described.


The inhibiton of adrenergically provoked renin release by salbutamol in man. 1 The beta-adrenoceptor agonist salbutamol is shown to have antagonist properties by its effect on adrenergically provoked renin release in normal people. 2 It significantly reduces the rate of renin secretion provoked by either endogenous (85 dregrees head-up tilt) or exogenous (isoprenaline infusion) adrenergic stimulation. 3 Because renin is relatively simple to measure, and because in acute studies its release is relatively uninfluenced by the vagaries of direct and reflex cardiovascular effects, we suggest that, in the characterization of drugs which act on adrenergic beta-receptors, an assessment of their effects on renin release would be useful.


Comparison of plasma and saliva levels of metoprolol and oxprenolol. 1 Plasma and saliva levels of metoprolol and oxprenolol have been compared in two groups of healthy volunteers. 2 Mean salivary oxprenolol levels were lower than, but closely related to the corresponding plasma levels (r=0.93), the mean ratio of saliva:plasma concentration being 0.42. 3 Mean salivary metoprolol concentrations were considerably greater thatn the corresponding plasma levels and the relationship between the concentrations in the two fluids was less clear. 4 The evidence presented suggests that oxprenolol diffuses passively whilst metoprolol is actively secreted into saliva. The mechanism involved in the active process is not known.


Standardized stress and hypertension: comparison of effect of propranolol and methyldopa. 1 Using a standardized form of mental stress, 21 patients with idiopathic hypertension were investigated before and after treatment with placebo (n=8), propranolol (n=7) or methyldopa (n=6). 2 Blood pressure was satisfactorily controlled in the propranolol and methyldopa groups but only the propranolol group showed modification of the pressor response to stress testing. 3 These results suggest that propranolol may provide more uniform control of blood pressure than methyldopa in patients with essential hypertension.


Outcome of pregnancy in mothers given bromocriptine. 1 Information has been obtained on the outcome of 448 completed pregnancies in mothers who had been given bromocriptine at some stage in the early weeks of pregnancy. 2 The frequencies of spontaneous abortions, twin pregnancies and malformations have been compared with those reported for 'normal' populations. 3 Based on this limited material, we conclude that the use of bromocriptine to restore fertility in hyperprolactinaemic women is not associated with an increased risk of abortion, multiple pregnancy or the occurrence of malformations in the infants.


Bumetanide and frusemide: a comparison of dose-response curves in healthy men. 1 Log dose-responses for the loop diuretics bumetanide and frusemide in healthy subjects deviated significantly from parallelism as regards urine volume and sodium excretion. Ignoring the nonparallelism the best estimate of natriuretic potency (bumetanide: frusemide) was 46:1 in the bumetanide dose range 0.5-2 mg. 2 For a given natriuresis the urinary potassium excretion following bumetanide was significantly lower than that for frusemide within this dose range. 3 The data illustrate the limitations of studies comparing diuretics at a single dose level. Extrapolation of the observed log dose-response curves provides one possible explanation for the relative potency (bumetanide: frusemide) of 20:1 reported when the drugs are used at high dosage in patients with renal failure.


Chenodeoxycholic acid therapy for hypertriglyceridaemia in men. 1 Ten consecutive patients with hypertriglyceridaemia who adhered to a low carbohydrate diet without complete control of serum triglycerides were started on chenodeoxycholic acid 750 mg daily and followed monthly for 6 months. Nine of these patients were then followed for a further month on placebo capsules and thereafter monthly for a further 6 months on clofibrate 2 g daily. 2 The mean serum triglyceride level fell by 36% after dietary treatment alone (P less than 0.05) and by 47% from initial values on diet plus chenodeoxycholic acid (P less than 0.01). In the nine patients who proceeded to clofibrate therapy there was a rise in triglyceride levels on placebo capsules to the level achieved by diet alone, and a further fall on diet plus clofibrate of 47% of initial values (P less than 0.05). 3 Chenodeoxycholic acid therapy is effective in the management of hypertriglyceridaemia not completely cured by dietary measures, and may be as efficacious as clofibrate.


The effects of intravenous isoxsuprine on blood viscosity in patients with occlusive peripheral arterial disease. 1 Blood viscosity is thought to be a major factor in disorders of the peripheral circulation. 2 Ten patients with obliterative arterial disease received an infusion of isoxsuprine of 20 micrograms kg-1 for 30 min. The infusion was followed by a highly significant and prolonged fall in blood, plasma and serum viscosity, in haematocrit and in plasma fibrinogen concentration. Blood lipid levels were also studied: total lipids and total cholesterol did not alter; triglyceride level was significantly lowered at the end of, and after, drug infusion. 3 There was no change in blood, plasma or serum viscosity in the four patients receiving a control infusion 2 days before the infusion of isoxsuprine. 4 The relationships between lowered viscosity and increasing peripheral tissue perfusion are discussed.


Toxicity of nitrazepam in the elderly: a report from the Boston Collaborative Drug Surveillance Program. 1 To assess the potential hazards of nitrazepam therapy of insomnia in the elderly, adverse reactions to nitrazepam were studied in 2111 hospitalized medical patients who received the drug. 2 Manifestations of unwanted central nervous system (CNS) depression (such as drowsiness or 'hangover') were reported in 49 nitrazepam recipients (2.3%), and signs of unwanted CNS stimulation (such as nightmares, insomnia, agitation, etc.) in 15 (0.7%). None of the adverse reactions were considered serious. 3 Physician-rated clinical efficacy of nitrazepam was not related to dose, but the frequency of both types of adverse reactions increased significantly at higher daily doses. CNS depression also was significantly more frequent in the elderly, being reported in 11% of those aged 80 years or older, whereas the frequency of CNS stimulation was not correlated with age. 4 The effect of age on the reported rate of unwanted CNS depression was most striking at high doses. Among patients aged 80 years or over whose daily dose averaged 10 mg or more, 55% experienced unwanted CNS depression attributed to nitrazepam. 5 Low doses of nitrazepam are safe for elderly individuals, but the elderly are readily susceptible to excessive CNS depression at high doses. The findings suggest that there is little reason to exceed 5mg doses of nitrazepam for most patients, particularly those who are elderly.


The effect of low dose carbidopa/levodopa on prolactin and growth hormone concentrations in patients with breast cancer and in benign breast tumours. 1 Low doses of carbidopa/levodopa (12.5 mg 1-alpha-methyl-dopahydrazine, 125 mg levodopa) were administered orally to 29 patients with tumours of the breast (16 with breast cancer, 13 with benign breast disease). 2 Plasma dopa response curves were similar in all the patients studied. 3 Prolactin and growth hormone showed similar responses to carbidopa/levodopa irrespective of age or diagnosis. 4 Prolactin showed an unusual reponse in four patients which has not previously been recorded.


Enhanced elimination of warfarin during treatment with cholestyramine. 1 The elimination and anticoagulant activity of a single intravenous dose of warfarin (1.0-1.2 mg/kg) without and with concomitant cholestyramine treatment (about 4 g three times daily) was studied in five healthy male subjects. 2 Cholestyramine treatment decreased the biological half-life of plasma warfarin (from a mean value of 2 days -1.3 days) and increased the total clearance of this drug (from a mean value of 37 ml kg-1 day-1--53 ml kg--1 day--1). 3 The total anticoagulant effect per dose of warfarin, as measured by the area under the effect v time curve, was also reduced by cholestyramine (average reduction of about 25%). 4 Warfarin possibly undergoes enterohepatic recycling in man which can be interrupted by cholestyramine.


A thermographic assessment of three intra-articular prednisolone analogues given in rheumatoid synovitis. 1 Three intra-articular prednisolone analogues have been studied in a group of forty-six rheumatoid arthritic subjects. Each compound was tested at 50 mg and 100 mg dose over 3 weeks. 2 The anti-inflammatory effect was assessed by quantitative thermography. Systemic escape of the drug was monitored by plasma prednisolone and cortisol levels. 3 Both the systemic escape from the joint and the duration of effect on injected and uninjected knees were related to drug solubility. 4 Depression of plasma cortisol occurred with all three preparations and was most prolonged with the long-acting preparation. 5 Increasing the dose from 50 mg to 100 mg increased the antiflammatory effect only with the soluble acetate preparation.


(+)-Propranolol clearance, an estimation of hepatic blood flow in man. 1 Hepatic blood flow was determined before and during (+)- and (+/-)-propranolol plasma concentration plateaus in 19 patients with suspected renal hypertension and normal liver function. 2 Hepatic blood flow significantly decreased (P less than 0.001) during (+/-)-propranolol administration and remained unchanged during (+)-propranolol administration. 3 Hepatic extraction ratio was 74 +/- 1% (+/-)-propranolol and 79 +/- 2% for (+)-propranolol. 4 Total propranolol clearances were determined during the steady-state achieved by a constant infusion. A highly significant positive relationship was observed (r = +0.86; P less than 0.01) between hepatic blood flow and (+)-propranolol clearance. The slope of the curve was 1.05 +/- 0.27. 5 The result implies that the total clearance of (+)-propranolol constitutes an accurate estimation of basal hepatic blood flow in subjects with normal liver function.


Influence of soft gelatin on digoxin absorption. 1 The influence of encapsulation in soft gelatin on the absorption of digoxin from a solvent mixture of polyethylene glycol 400 90% W/W, ethanol 6% W/W, propylene glycol 3% W/W and water 1% W/W was studied in eight healthy volunteers. 2 Each volunteer received 0.6 mg digoxin as solution alone, as three intact capsules containing digoxin solution, as three capsules containing digoxin solution sectioned in half and as three capsules containing digoxin solution dissolved in water prior to administration. 3 There was no significant difference between the four treatments in terms of area under the plasma concentration--time curves for 7 h, peak plasma concentrations, time to peak or in the cumulative urinary excretion for 6 days. 4 It is suggested that a constituent of the solvent rather than the presence of or encapsulation within soft gelatin may be the determining factor in enhanced absorption of digoxin from soft gelatin capsules as compared to aqueous solution or tablets of rapid dissolution rate.


The influence of digoxin particle size on absorption of digoxin and the effect of propantheline and metoclopramide. 1 The influence of particle size on absorption of digoxin was studied in ten healthy volunteers who received 0.5 mg digoxin as two standard Lanoxin tablets, or tablets containing micronized digoxin or large particle size digoxin. Tablets were given 30 min after 15 mg propantheline, 10 mg metoclopramine or a placebo tablet, and following an overnight fast. 2 The overall mean cumulative 4 day urinary excretion of digoxin was significantly lower (P less than 0.01) after large particle size digoxin than after standard or micronized digoxin. Mean cumulative urinary excretion following large particle size digoxin was reduced when administered after metoclopramide and increased after propantheline, the difference between these two treatments being significant (P less than 0.05). There was a significantly lower (P less than 0.05) overall mean cumulative excretion following standard by comparison with micronized digoxin. However, by comparison with placebo, neither metoclopramide nor propantheline significantly altered mean cumulative excretion after standard or micronized digoxin. Propantheline and metoclopramide affect absorption of digoxin from formulations of large particle size and slow dissolution rate only.


The application of HPLC to the determination of some 1,4 benzodiazepines and their metabolites in plasma. 1 A high pressure liquid chromatographic (HPLC) assay has been developed for the measurement of chlordiazepoxide and its metabolites, N-desmethylchlordiazepoxide and demoxepam in microgram concentrations in human plasma. 2 Another metabolite was detected in appreciable amounts in the plasma from patients receiving high doses of chlordiazepoxide after the first 3 days of treatment. 3 Preliminary studies would indicate that this metabolite is N-desmethyldiazepam. 4 A modified HPLC system, using a microparticulate column was developed to separate N-desmethyldiazepam from chlordiazepoxide and its other metabolites in plasma.


Identification of hydrallazine and hydrallazine hydrazone metabolites in human body fluids and quantitative in vitro comparisons of their smooth muscle relaxant activity. 1 Serum and urine from hypertensive subjects on chronic oral hydrallazine therapy were studied using gas chromatographic/mass spectrometry techniques. 2 Metabolites resulting from acetylation, hydrolysis and conjugation reactions were detected. The acetone, pyruvate and alpha-ketoglutarate hydrazone were identified. 3 The activity of the pyruvate and alpha-ketoglutarate hydrazones were compared with that of hydrallazine using isolated rabbit aortic strips. 4 Both hydrazones were active under in vitro conditions, producing smooth muscle relaxant effects equal to those of hydrallazine. 5 It is concluded that hydrazone metabolites will contribute to the hypotensive effects of hydrallazine therapy in proportion to their relative abundance, persistence in vascular tissues and intrinsic activity.


Prednisone or prednisolone for the treatment of chronic active hepatitis? A comparison of plasma availability. 1 The plasma availability of prednisolone after oral doses of prednisolone and its precursor, prednisone, were compared in ten normal controls and twenty-five patients with chronic active hepatitis by estimation of the area under the plasma concentration--time curve for the drug (AUC). 2 In controls, values for AUC were significantly more variable after prednisone than prednisolone, and two subjects showed markedly inefficient conversion of prednisone to prednisolone. In patients, variability was similarly wide after both preparations, but overall bioavailability after both prednisone and prednisolone was similar to that found in controls, although three patients showed subnormal values after both preparations, possibly as a result of impaired intestinal absorption. 3 Patients with biochemical and histological evidence of active hepatocellular necrosis showed evidence of impaired activation of prednisone, but this was compensated for by a decreased rate of elimination of prednisolone from the plasma. 4 It is concluded that plasma prednisolone levels will be more predictable after prednisolone than after prednisone in subjects without hepatic dysfunction. In the presence of liver disease, because of the marked variability in plasma prednisolone levels after either drug, estimation of these could be of value in those patients whose disease cannot be controlled by normal maintenance doses.


Bronchodilator effect of delta1-tetrahydrocannabinol. 1 delta1-trans-tetrahydrocannabinol, (delta1-THC) produces bronchodilatation in asthmatic patients. 2 Administered in 62 microliter metered volumes containing 50--200 microgram by inhalation from an aerosol device to patients judged to be in a steady state, it increased peak expiratory flow rate (PEFR) and forced expiratory volume in 1 second (FEV1). 3 The rate of onset, magnitude, and duration of the bronchodilator effect was dose related.


Kinetics of changes in the crypts of the jejunal mucosa of dimethylhydrazine-treated rats. When symmetrical 1,2 dimethylhydrazine was administered to rats by weekly s.c. injection, 37% of the animals had developed small intestinal carcinomas after 21-27 weeks. These lesions were largely localized to duodenum and upper jejunum. At the same time there was a diffuse crypt hyperplasia in the jejunum which affected all the treated animals, not just those with neoplasms. This marked hyperplasia was preceded by a modest sustained crypt elongation which was seen soon after DMH injections began. In these hyperplastic jejunal crypts the absolute size of the proliferative compartment was increased, but the growth fraction calculated from labelling studies appeared to fall, probably by reduction in relative size of the proliferating population within the proliferative compartment. No convincing alteration in actual cell-cycle time was observed in the abnormal crypts. There was a slight (25%) increase in cell-production rate in the abnormal crypts.


Mass and number of fibres in the pathogenesis of asbestos-related lung disease in rats. Five groups of rats were treated by inhalation for 12 months, with the U.I.C.C. preparations of the 3 main commercially used asbestos types, chrysotile, crocidolite and amosite. The experiment was designed so that the effects of both fibre mass and fibre number could be examined. The results indicated that chrysotile dust caused far more lung fibrosis than either amphibole type even when the fibre numbers in the dust clouds were similar. All malignant pulmonary neoplasms found during this study occurred in animals treated with chrysotile. The fibre-number calculations used for the generation of dust clouds were evaluated using the parameters recommended by the Health and Safety Executive in 1976, by which all fibres over 5 microgram long are counted using a phase-contrast light microscopy. When fibre-length distributions were calculated using a scanning electron microscope, however, it was found that the chrysotile clouds used in this study contained many more fibres over 20 microgram long than either of the amphibole clouds. The results, therefore, support previous suggestions that long asbestos fibres are more dangerous than short. They also indicate that neither a single mass standard, nor the present fibre-number standards are satisfactory.


Saccharide alterations in rat kidney associated with malignant transformation by injection of dimethylnitrosamine. Renal tumours were induced in dietary-primed rats by injection of dimethylnitrosamine. Control and tumour tissue was excised at varying periods and maintained in short-term organ culture in the presence of 3H- or 14C-fucose. The plasma membranes were then isolated, and the isotopic profiles of normal kidney and renal tumour membrane proteins were established, using polyacrylamide-gel electrophoresis in dodecyl sulphate. Several fucose-containing glycoproteins of the plasma membranes were found to alter upon neoplastic transformation: 4 increased and 3 decreased. The probable identity of 2 of these proteins is indicated: alpha-foetoprotein is one of the glycoproteins which increased, whereas neutral endopeptidase decreased in the tumour membranes. Fluorescein-labelled lectin binding by the kidney tissue was also found to alter upon transformation. The most marked changes were an increase in sialic acid (neuraminidase-sensitive) and galactosamine (Ricinus communis agglutinin Type I) in the nuclei of some neoplastic cells and some hyperplastic-tubule cells.


Stability of transplanted murine tumour systems after storage of cells at -196 degrees C for up to 13 years. Two murine lymphomas of spontaneous origin were stored in liquid N2 as cell suspensions in DMSO for 8 and 13 years respectively. Isogenic transplantation assays done some years before freezing and immediately after thawing indicated no measurable loss of clonogenic cells during freezing, storage or thawing; the number of cells required for 50% successful transplantation remained close to unity in both cases. The overall data revealed no evidence of an alteration of the receptivity of the mouse colonies over a period of 13 or 20 years. We attribute this remarkable stability to close supervision of the systems within a single laboratory.


Macrophage-mediated natrual cytotoxicity against various target cells in vitro. I. Macrophages from diverse anatomical sites and different strains of rats and mice. Adherent, predominantly phagocytic, mononuclear cells expressing spontaneous cytotoxic activity against diverse target cells in vitro were present in various tissues of different strains of rats and mice. Cells with such natural killer capacity were thus everywhere readily available for mobilization and activation. The inherent spontaneous killer capacity of adherent mononuclear phagocytes can be abrogated by silica particles in vitro, and can be considerably enhanced by appropriate stimuli in vivo. Spontaneous cytolysis mediated by unstimulated mononuclear phagocytes was consistently manifested only after a lag phase of 12-20 h and was quite nonspecific; there was no cogent correlation between susceptibility to lysis and transformation.


Macrophage-mediated natural cytotoxicity against various target cells in vitro. II. Macrophages from rats of different ages. Adherent, predominantly phagocytic mononuclear cells from various rat tissues express spontaneous cytoxicity against diverse target cells in vitro. The extent to which cytotoxicity was expressed by effector cells depended on the age of donors. Cytolytic effector-cell capacity was already fully developed a few days after birth, and persisted over many months, but was clearly reduced in senescence. Similarly, the ability to intensify natural cytotoxicity by peptone in vivo was already fully manifested in the newborn, but was significantly diminished in old rats.


Monocytes and macrophages in malignant melanoma. III. Reduction of nitroblue tetrazolium by peripheral blood monocytes. Peripheral-blood monocytes from normal individuals and from patients with malignant melanoma reduce nitroblue tetrazolium (NBT). A quantitative assay for dye reduction was applied to 25 healthy donors and 31 patients with malignant melanoma. NBT reduction expressed as dye reduction per monocyte was significantly impaired in patients with disseminated disease, and they responded poorly to a phagocytic stimulus. Monocytes from patients with micrometastatic disease, however, showed normal resting NBT reduction but, following exposure to a suspension of latex-polystyrene, showed significantly greater NBT reduction than those from normal individuals. Since NBT reduction is an indirect measure of intracellular hexose-monophosphate-shunt activity we conclude that the monocytes from patients with minimal disease are in some way activated.


Antigen shedding by human breast-cancer cells in vitro and in vivo. Human breast cancer cells were adapted to chemically defined medium in order to recover naturally shed glycoproteins. Sephadex G-150 chromatography of these glycoproteins revealed 1 major and 2 minor peaks. When the cells were grown in the presence of 3H-leucine, the radioactive shed proteins had a Sephadex profile identical to the unlabelled shed glycoproteins. PAGE analysis of these proteins showed 5 major bands. Antigenically similar proteins were found in the serum of female nude mice bearing BOT-2 tumours, but not in controls.


Response of tumour-related and normal lymphocytes to antigens on fibroblasts from embryos of varying age. The in vitro cytotoxic immune response of spleen lymphocytes from primiparous and tumour-related mice to embryonic cells from embryos of varying age and tumour cells has been investigated. The results indicate that lymphocytes from both primiparous and tumour-related (i.e., tumour-bearing or tumour-excised) animals give a response which is greater than that from cells from control mice ("virgin cells"). Moreover, in this putative anamnestic response the immune cells detect antigenic differences in the cell populations of embryos of varying age, which are not as readily demonstrable when cytotoxicity is derived from virgin cells. As a further indication of the in vivo priming to embryo-assoicated antigens, the data show that the precursors of cytotoxic cells apparently undergo a blastogenic response in the presence of embryo antigen, and revert to small quiescent cells when antigen is removed, in a way entirely analogous to that described for reactivity of mixed leucocyte cultures to antigens of the major histocompatibility complex. Finally, it seems that in animals immediately after removal of embryonic antigen (and to a lesser degree in virgin or late-embryo-immune mice) there exists a suppressor cell population which inhibits an anti-embryo cytotoxic response far more than an antiallograft response.


Fluorescence-polarization changes in mononuclear blood leucocytes after PHA incubation: differences in cells from patients with and without neoplasia. In 32 healthy blood donors, 20 patients with histologically verified cancer and 18 patients with non-neoplastic diseases, the fluorescence polarization changes of fluorescein samples incorporated in mononuclear leucotyes were measured after incubation with PHA. The leucocytes of healthy persons, and 16/18 persons with non-neoplastic diseases, responded with a decrease in the degree of fluorescence polarization by about 20% from that in non-PHA-stimulated cells. In 19/20 patients with a variety of malignant tumours, the leucotyes did not respond to PHA stimulation with such a decrease. The exceptions among the patients with neoplastic and non-neoplastic diseases are considered, and may not be "false-negative" or "false-positive" respectively, but indicative of a particular situation in that disease. The biophysical mechanisms underlying the observed changes remain to be investigated.


Natural cytotoxicity of haemopoietic cell populations against murine lymphoid tumours. Homozygous nude and normal mice of 3 strains, BALB/c, CBA and C57BL, were used as sources of nucleated haemopoietic "natural killer" (NK) cells. These killer cells could lyse a wide range of syngeneic and allogeneic lymphoid tumour cell lines in vitro, and it was found that cell suspensions from nude mice were always significantly more active than those from normal mice, and that the most active effector population was a polymorph-enriched peritoneal-exudate cell suspension. Eosinophils did not appear to be involved in the phenomenon, and mononuclear peritoneal-exudate cell suspensions were actually highly inhibitory. Three non-lymphoid tumours, a carcinoma, a fibrosarcoma and a mastocytoma, were totally resistant to in vitro lysis. Although all susceptible tumour cell lines were C-type virus-associated, not all of these tumours were killed by all strain sources of spleen cells, indicating a specificity of killing.


Combined treatment of a solid tumour by local hyperthermia and actionomycin D. (BALB/c X C57BL/6)F1 mice bearing an SV-40 fibrosarcoma in the limb were injected with 0.045, 0.09 and 0.18 microgram/g body wt actinomycin D into the tumour. Similar animals were also treated with local hyperthermia (39.7 degrees, 42.3 degrees and 43.6 degrees C intratumour temperature for 30 min). The marked increase in median survival time following the combination of drug and local hyperthermia indicates that the combined treatment has a synergistic effect in the control of solid tumours. The median survival time of animals receiving the two treatments in immediate succession was higher than in animals with 30 min between treatments. This has important implications for the therapy of human cancer.


Evaluation of single-agent therapy in human colorectal tumour xenografts. The response of 6 human colorectal tumour xenografts to 7 cytotoxic agents have been established. Tumour responses have been quantified by growth inhibition, and the time taken for 3H-thymidine fractional incorporation (TFI) to recover to the control value after treatment. The chemosensitivity of each tumour line to a spectrum of agents was individual, and no pattern of response which would allow prediction of individual agent efficacy was apparent. Cyclophosphamide, methyl-CCNU and 5-fluorouracil produced marked growth inhibition in individual tumour lines, whereas actinomycin-D, cis-dichlorodiammine platinum, doxorubicin and pentamethylmelamine showed little activity. Data presented agree with clinical evaluation for single-agent therapy. The uptake and incorporation of radiolabelled 5-fluorouracil into 4 tumour lines is reported. No marked differences between 3 FU-insensitive lines and 1 sensitive line have been observed.


Liver blood flow measurements in the portacavally transposed rat before and after partial hepatectomy. The haemodynamic changes following partial hepatectomy (PH) in the portacavally transposed rat have been studied using an 85Kr clearance technique. Liver blood flow measurements (LBF) were made before and after portacaval transposition (PCT) and PH was performed either immediately or at 3 weeks after transposition and further blood flow measurements made. No change in LBF was noted after PCT compared with preoperative values. Following PH in the portacavally transposed animals there was no marked increase in LBF. It is suggested that the liver atrophy consequent on portal diversion is due to deviation factors in portal blood and not to a decrease in absolute LBF. Regenerative hyperplasia occurs in the absence of the post-hepatectomy rise in LBF seen in normal animals.


The inflammatory response to paraffin in the peritoneal cavity of the rat. The inflammatory response to intraperitoneal paraffin in hte rat has been defined in terms of the fluid influx and the pattern of cell accumulation. The volume of fluid exudate in the peritoneal cavity was small and did not change dramatically with time, but there was a moderate cellular influx which was biphasic with peaks at 24 and 72 h. Mononuclear phagocytes and eosinophils were the major cell types found in the exudate, neutrophils, lymphocytes, and mast cells being much less numerous. The neutrophil influx was apparent by 4 h. It was early, short-lived and of low magnitude. In contrast, the eosinophil response was later and more prolonged, cell numbers reaching a peak at 72 h when they were the predominant cell type. The response of the mononuclear phagocytes was multiphasic, with peaks in cell numbers occurring at 24 and 96 h, and 3 weeks after stimulation, by which time they exhibited the morphological features of large activated macrophages which were highly phagocytic for paraffin. The method is useful for the production of mixed inflammatory cell populations from which the fluid phase can readily be separated, and may be a valuable model for the study of esoinophil kinetics.


Isoprenaline-induced myocardial necrosis in dogs. Subcutaneous injections of isoprenaline sulphate in dogs (1-3 mg/kg) resulted in myocardial injury. Good correlation was observed between abnormal ECG recordings, serum enzyme concentrations and myocardial lesions in the acute phase of injury. However, in cases where less extensive myocardial injury was produced due to lower doses of isoprenaline or in cases of the reparative phase of the isoprenaline-induced myocardial injury, serum enzymes were not useful indicators of the change. Similary, ECG recordings taken peripherally also did not show alteration in the reparative phase of the injury in spite of extensive myocardial lesions.


The rate of development of postmortem artefact in the small intestine of neonatal calves. The rate of development of postmortem artefacts was investigated in the mucosa of the small intestine of a calf dually infected with an enteropathogenic strain of Esch. coli and rotavirus, and an uninfected control calf. Samples were removed under general anaesthesia from the proximal, middle and distal small intestine and compared with those taken from adjacent sites 1-30 min after severing the major blood vessels of the neck. In the challenged calf, changes occurred in the villous mucosa by 3 min after severance, whilst in the control calf good fixation was obtained until 10 min after severance.


The cytotoxic effects of asbestos and other mineral dust in tissue culture cell lines. The cytotoxic effects of 15 dusts have been tested in 2 cell lines. Experimental animal data are available for 11 of the 15 dusts. There is a correlation between the cytotoxic activities of the dusts and the ability to induce mesothelial tumours following intrapleural injection of the dusts. Some preliminary observations on the nature of interaction between the dusts, medium components and the cells are reported. It is suggested that the study of the interactions between cells and dusts in culture may lead to an understanding of the pathogenesis of these dusts in man and animals.


Association of foetal wastage with influenza infection during ferret pregnancy. Inoculation of influenza virus into pregnant ferrets during the late gestational period was investigated. Foetal resorption followed intracardial inoculation of a large dose of influenza virus (10(9.4) EBID50) and a 100-fold lower dose caused lower litter sizes at birth. The possible role of fever in foetal resorptions was largely discounted by 2 observations: a non-pyrexic dose inoculated intracardially into the pregnant ferret still had detrimental effects on foetal viability; influenza virus inoculated intranasally caused a pyrexia but did not affect the progeny. The potential of the ferret as a model for studying the possible adverse effects of influenza during pregnancy is discussed.


Effects of lymecycline on Mycoplasma pulmonis-induced arthritis in mice. The effect of lymecycline treatment on arthritis in C3H mice produced 5 months previously by i.v. inoculation of Mycoplasma pulmonis was examined. Treatment had little effect on the severity of the clinical disease. However, there was a marked reduction the severity of the histopathological inflammatory reaction in joints from lymecycline-treated mice when compared with untreated controls. This reduction was associated with eradication of viable mycoplasmas from the joints. The findings suggest that persistent arthritis in C3H mice is due to the continued presence of viable M. pulmonis organisms in the joint tissues.


Effect of carrageenan on activity of the mononuclear phagocyte system in the mouse. Injection of 5 mg carrageenan caused hepatosplenomegaly and thymic involution and resulted in temporary blockade of the mononuclear phagocyte system (MPS). Impaired MPS activity was shown by decreased hepatic phagocytosis of i.v. injected colloidal carbon and 51Cr-labelled sheep red blood cells (SRBC). Depression of Kupffer cell activity was dependent on carrageenan dose, route of administration and interval between carrageenan and particle injection. Reduction in hepatic uptake of SRBC was accompanied by increased localization of these cells within the spleen.


Morphologic changes of the junctional complex of the hepatocytes in rat liver after bile duct ligation. Using freeze-fracture techniques, we have examined the changes in the morphology of the tight junctional network around the canalicular lumen of the hepatocytes in rat liver after experimental bile-duct ligation. The more or less regular belt of parallel strands formed by the tight junctions around the canalicular lumen of normal hepatocytes is changed after extrahepatic obstruction. A more irregular network is formed withe a reduced number of strands which also extend more in an abluminal direction with formation of irregular loops. Striking changes are seen at the gap junctions: the small patches normally situated within the tight junctional network become less numerous; at some canaliculi they are even absent; also the larger gap junctional areas normally present in deeer abluminal extensions of the lateral cell membrane become hard to find or are even absent. This altered tight junctional pattern suggests an increased permeability so that the pathway of intercellular escape of biliary constituents towards the blood stream in cholestasis becomes as plausible as transhepatocytic regurgitation. The disappearance of the gap junctions would result in a lack of intercellular communication and uncoupling of liver cells, which may lead to a more individual behaviour of adjecent hepatocytes, explaining the heterogeneity in canalicular changes in cholestasis.


Erythrokeratolysis hiemalis--keratolytic winter erythema or 'Oudtshoorn Skin'. A new epidermal genodermatosis with its histological features. A new autosomal, dominantly inherited epidermal disorder is described in which a spreading dissection of the stratum corneum with redness of the palms and soles occurs as a result of a centrifugal necrobiosis of the Malpighian layer below it. Iis is seen characteristically in winter. In extensive cases the limbs and trunk are affected with gyrate scaling erythemas.


Chilblain lupus erythematosus (Hutchinson). A clinical and laboratory study of 17 patients. Chilblain lupus erythematosus (LE) is a chronic unremitting form of LE ssen predominantly in women. It occurs commonly on the digits, calves and heels. Nasal lesions are rare. Chronic facial discoid LE usually appears before the chilblain form but, in most instances, resolves even though the chilblain lesions persists. Transformation to systemic LE occurs more often in those who develop both forms of cutaneous LE simultaneously and in the erythema multiforme syndrome. The chilblain lesions are the result of microvascular injury secondary to exposure to cold and possibly hyperviscosity from immunological abnormalities, Elevated serum gammaglobulins, positive latex factor and speckled pattern antinuclear factor are common. None of the usual treatments for cutaneous LE is effective for the chilblain lesions, probably because none is directed towards prevention and treatment of the microvascular stasis.


Lymphocyte subpopulations, serum immunoglobulins and complement factors in patients with atopic dermatitis. The percentages of lymphocytes carrying different classes of membrane-bound Ig, and lymphocytes forming rosettes with sheep erythrocytes (E-RFC), as well as lymphocytes with receptor for the Fc-part of IgG (EA-RFC) were determined in 19 patients with atopic dermatitis. Lymphocyte suspensions were also stained with a specific rabbit anti-human T-lymphocyte antiserum. Furthermore, the serum concentration of IgG, IgA, IgM and IgE and the complement factors C3 and C4 were measured. A small but significant increase in lymphocytes with membrane-bound IgE and an increase in the serum concentration of IgE and complement factor C4 were observed. A decrease in the percentages of lymphocytes with receptors for sheep erythrocytes (E-RFC) was also found. The percentages of lymphocytes that stained with the anti-T antiserum correlated well with the percentages of lymphocytes forming rosettes with sheep erythrocytes. In one patient we found increased IgE positive lymphocytes, increased IgE serum concentration and a decreased T-cell number.


Comparative electron microscopic study between Mendes da Costa's disease and recessive epidermolysis bullosa dystrophica. An electron microscopic study of Mendes da Costa's disease (MCD) has been undertaken to determine whether this disease is a variant of epidermolysis bullosa dystrophica, or should be classified as a separate disease entity. It was shown that in MCD lacunae occur in the lower layers of the epidermis, in the presence of normal anchoring fibrils. In the recessive form of epidermolysis bullosa dystrophica (EBD), however, no lacunae were found in the epidermis, and anchoring fibrils were absent. These findings support the concept that MCD should not be considered as a special form of epidermolysis bullosa dystrophica.


Skin temperature changes induced by UV irradiation at 254 nm and 300 nm. Skin temperatures 24 h after irradiation at both 254 and 300 nm have been examined using the technique of thermography. Increases in skin temperature have been recorded at both wavelengths but the magnitude of these differences after 254 nm irradiation is influenced by the ambient temperature. The apparent disagreement between two groups of observers working in the field of UV erythema may well have been explained.


The effects of mental and physical stress on the incidence of skin disorders. The effect of civil unrest and terrorism in Northern Ireland from 1969 on skin diseases which are generally accepted to be aggravated by stress and strain has been studied (1) by reporting cases making claims against the government for skin diseases developed as the result of violence and (2), studying changes in the pattern of skin diseases at skin clinics in Northern Ireland over the last 10 years. There has been little change in the pattern of skin diseases which could be attributed to mental or physical stress.


Wiskott-Aldrich syndrome with partial response to transfer factor. A male infant presented with dermatitis, purpura and susceptibility to bacterial infections. The clinical diagnosis of Wiskott-Aldrich syndrome was confirmed and after full immunological assessment, treatment with transfer factor was commenced. This has resulted in a rise in the platelet count and improvement in the bleeding tendency. This improvement in the haematological aspect of the disease has, however, been accompanied by exacerbations of the cutaneous lesions.


Familial lichen planus. Another disease or a distinct people? When lichen planus strikes families, a very rare happening, it is likely to afflict younger members, to erupt more acutely, extensively, and gravely, attacking also nails and mucous membranes, and to recur. Ten patients with familial lichen planus, two each from five distinct Caucasian families, the parents of whom were unrelated by birth, were found to be carrying HLA-B7 statistically more frequently than in the normal population or in those with the characteristic forms of lichen planus. We hint that their genotype might have rendered them susceptible to a pathogen that precipitated their disease.


Familial lichen planus. A case report.

Familial lichen planus. A case report. A Jewish Shirazee family is described in which 6 members had lichen planus. There was no increased incidence of the phenotype HLA A3.


Mortality among Boston firefighters, 1915--1975. Although the nature of firefighting involves particular health hazards, previous mortality and morbidity studies of firemen have produced inconsistent evidence for an increased risk of mortality from cardiovascular disease, respiratory disease, cancer and accidents. Mortality experience since 1915 has been examined in 5655 Boston firefighters, comprising all male members of the city fire department with three or more years of service. The observed cause of death as stated on the death certificates of 2470 deceased firefighters has been compared with the numbers expected based on rates for the male population of Massachusetts and of the United States of America. Among all firefighters, deaths from all causes were 91% of expected. The standardised mortality ratio (SMR) was markedly reduced (less than 50) for infectious disease, diabetes, rheumatic heart disease, chronic nephritis, blood diseases and suicide. The SMR was 86 for cardiovascular deaths, 83 for neoplastic deaths, and 93 for respiratory deaths. The SMR for accidents was 135 for active firefighters. The results suggest that the survival experience of firefighters is strongly influenced by strict entry selection procedures, ethnic derivation, and sociocultural attributes of membership. While excessive morbidity has been demonstrated in firefighters, there does not appear to be a strong association between occupation and cause-specific mortality.


Radiological abnormalities in electric-arc welders. Chest radiographs of 661 British electric-arc welders have been examined by three film readers experienced in the radiology of pneumoconiosis. About 7% of the welders showed signs of small rounded opacities of category 0/1 or greater. No definite evidence of large opacities (Progressive Massive Fibrosis) was seen. The prevalence of chest abnormalities other than pneumoconiosis was 7%. A clear association between prevalence of small rounded opacities of category 0/1 or greater and years of exposure to fumes was established, although few signs of severe grades of simple pneumoconiosis were seen.


Experimental asbestosis: an investigation of functional and pathological disturbances. I. Methods, control animals and exposure conditions. The measurement of respiratory function and quantitative assessment of changes in lung morphology are described in a long-term study of asbestos-exposed guinea pigs. Resistance and dynamic compliance of the guinea pig respiratory system were measured non-destructively, and the tidal volume and rate of spontaneous breathing were also determined. A point counting technique was used with histological preparations to quantify morphological changes. In one group of control animals, investigated between 3 and 28 months of age, dynamic compliance and tidal volume tended to increase, but resistance and breathing rate tended to decrease, as the animals matured. In contrast the percentage by volume of various lung components remained constant throughout this period. The animals were exposed to chrysotile and amosite aerosols, both aerosols containing high concentrations of short fibres (less than 5 micrometer) and at least 1000 fibres/ml longer than 5 micrometer. The total fibre concentration during chrysotile exposure was probably at least double that during amosite exposure. A gradient of fibre concentration (less than 5 micrometer) was detected along the exposure chamber, but this gradient was not reflected in the respiratory function of animals exposed at different positions along the chamber. These findings are discussed in relation to possible dose-dependence of the response.


Significance of fibre length in the clearance of asbestos fibres from the lung. Rats were exposed by inhalation to radioactive anthophyllite asbestos. Animals were then killed serially over a period of 205 days and the fibre content of the lungs measured radiometrically. The lungs were subjected to selective bronchopulmonary lavage and the mean fibre content determined of free cells recovered from the alveolar spaces. The length distributions of fibres recovered from the lungs by lavage, and of those remaining in the lungs following lavage, were measured. Short (less than 5 micrometer) fibres are cleared from the lung via the conducting airways more efficiently than longer fibres and fibres exceeding 50 micrometer in length are not removed from the lungs by this route. Although fibres of about 200 micrometer in length were present in all the lungs examined, the longest which could be recovered by lavage, once fibre deposited in the airways had been cleared, was only about 100 micrometer decreasing to 60-70 micrometer after 205 days. It is suggested that long fibres are more liable than short to penetrate the alveolar wall as they tend to bridge the alveolar ducts and alveoli.


The effect of body protein supply on resistance to cadmium. Six groups of 15 rats were fed on three diets, each differing in the quantity and quality of protein (17.87 as opposed to 8.85 g%, with or without the addition of 0.5 g methionine), one group of each pair of animals being injected subcutaneously with 0.3 mg Cd/kg body weight/day, for 13 weeks. The low protein diet increased the effects of cadmium, rendering them significantly more harmful than in animals which were given the normal protein diet. The incorporation of 0.5 g% DL-methionine in the low protein diet, without increasing the total nitrogen content, diminished the most marked effects induced by the same amounts of cadmium, so that their mean values were not significantly different from those found in the normal protein group treated with the same dose of the metal. The results show that a quantitatively and qualitatively adequate protein supply increased the resistance of the organism to cadmium, diminishing significantly the severity of symptoms induced by the metal.


A quick and simple method for the routine determination of acetyl- and butyrylcholinesterase in blood. The salient features of this method for biological monitoring of occupational exposure to organophosphorus insecticides are: (a) acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) are determined separately in whole haemolysed blood using specific substrates at appropriate concentrations; (b) 20 microliter of blood drawn from the finger tip is sufficient for both determinations; (c) the blood sample is immediately diluted with a solution of saponin and may thereafter be frozen for storage; (d) diagnostic kits, commercially available for the determination of plasma BuChE, may be employed with modifications; (e) the kinetic procedure is avoided by blocking the enzyme reactions at the end of the incubation period. This paper describes attempts to achieve optimal conditions for the two reactions. Under the conditions finally chosen, the whole blood 'AChE' activity value still includes a small percentage of plasma BuChE activity (12.5% of the total), while the whole blood 'BuChE' activity includes a small percentage of erythrocyte AChE activity (7% of the total). Results of determinations performed with this procedure on 172 healthy subjects are reported.


Relationship between clinical and electromyographic findings and exposure to solvents, in shoe and leather workers. A very high prevalence of polyneuropathy was observed in shoe and leather workers from the area of Florence. In addition, normal workers showed abnormally low maximal nerve motor conduction velocity. A linear decrease of motor conduction velocity was observed as a function of age and of the length of exposure to solvents. The worker population showed a steeper decrease with age than controls. A higher prevalence of polyneuropathy was observed when the amount of glue used by each worker per day was higher, and when the air volume of the plant was smaller. The subjective symptoms most frequently associated with polyneuropathy were muscle spasms, leg weakness and pain, and arm paresthesiae. Cases of polyneuropathy were more frequent in the workers exposed to solvents and in the older age group. A solvent aetiology of the disease is suggested, and glue substitution and proper hygienic conditions are recommended.


Ambulatory electrocardiography in car workers. A previous study in a car assembly plant showed that production-line workers had a lower incidence rate of heart attacks than executive staff. In the present study some major coronary risk factors and 24-hour ambulatory electrocardiograms were investigated in two age-matched samples of 30 middle-aged men drawn from these occupations. Men with a known history of heart disease were excluded. Compared with production-line workers, executive staff on average had a higher diastolic blood pressure (P less than 0.05) and fewer took heavy exercise during their leisure time (P less than 0.05). Ventricular premature beats (VPB was also similar for each of the periods of work, leisure and sleep. Apart from isolated ectopic beats, disturbances of rhythm were uncommon, and neither VPB nor other arrhythmias appeared to be induced by occupational factors.


The value of a scoring system in predicting outcome of pre-term labour and comparing the efficacy of treatment with aminophylline and salbutamol. A simple score, derived by allocating points to a selection of factors which influence the outcome of pre-term labour, was found to relate to the success of treatment. Used as a measure of the situation before therapy, this score can define a baseline allowing a realistic comparison of therapeutic methods. In this series, despite treatment, a large number of patients still were delivered before term and within a few days of admission to hospital. Thus it would seem that although drugs suppress uterine activity, they cannot neutralize the adverse effects of other factors associated with pre-term labour.


Plasma steroid changes in pre-term labour in association with salbutamol infusion. Serial measurements of peripheral plasma concentrations of progesterone and oestradiol-17beta were made in 23 women with singleton pregnancies who were given intravenous salbutamol in an attempt to inhibit pre-term labour. Mean levels of both hormones fell significantly during salbutamol infusion but returned to pre-treatment levels after therapy was stopped. Plasma human placental lactogen concentrations did not change during salbutamol infusion, suggesting that the fall in steroid hormone levels was unlikely to be an effect of altered uterine or placental blood flow.


Propranolol for the treatment of hypertension in pregnancy. Twenty-five women were treated with propranolol during 26 pregnancies complicated by hypertension. The fetal wastage, which had been 48 per cent before treatment with propranolol was reduced to 15.4 per cent, with one missed abortion and three stillbirths. Of the 22 liveborn infants 2 were small-for-dates but all 22 had Apgar scores of 9 or 10 at five minutes. There were no congenital anomalies in 25 viable infants and none of the 22 liveborn infants had clinical or laboratory evidence of hypoglycaemia. The blood pressure was controlled in 17 of 19 patients taking propranolol alone (40 to 160 mg/day) and in 6 of 7 taking propranolol with diuretics.


Thromboxane B2 in amniotic fluid before and during labour. Concentrations of thromboxane B2 (TXB2) have been measured in amniotic fluid obtained during late pregnancy and labour. Samples taken at amniocentesis contained significantly lower levels of TXB2 than samples taken by amniotomy for the induction of labour which in turn contained significantly less than when the same procedure was performed during labour. In the latter group there was no correlation between the degree of cervical dilatation and the concentration of TXB2. There was no correlation between gestational age and the concentration of TXB2 in amniotic fluid obtained at amniocentesis whereas there was a significant correlation (P less than 0.025) between these parameters when fluid was taken by amniotomy before labour. It is suggested that the relative activities of the enzymes responsible for the conversion of prostaglandin endoperoxides to prostaglandins, thromboxane A2 and prostacyclin may be of great importance during parturition.


Total and free cortisol in amniotic fluid during late pregnancy. Total cortisol levels were measured in 81 samples of amniotic fluid obtained from 72 patients in the third trimester of pregnancy; 19 of them had pre-eclampsia and the remainder had no pre-eclampsia, hypertension or renal disease. In accordance with previous studies, there was a rise in the concentration of amniotic fluid cortisol with advancing gestation; the rise was steepest after 40 weeks, the amniotic fluid cortisol levels invariably being above 700 nmol/l between 41 and 43 weeks of pregnancy. Amniotic fluid cortisol may thus be of value in diagnosing postmaturity. A relatively low correlation was found between total cortisol levels and lecithin/sphingomyelin ratios in amniotic fluid unless results were ranked for gestational age. Total cortisol concentrations in amniotic fluid obtained from patients with pre-eclampsia were significantly higher than in controls. The concentration of free cortisol in amniotic fluid changed much less than total cortisol. Thus total cortisol should be measured in studies of the fetal capacity to synthesize corticosteroids.


An International Collaborative Study of the assay of human placental lactogen: Establishment of WHO International Reference Preparation of human placental lactogen. A reference preparation of human placental lactogen (HPL) for use in immunoassays is described. In an international collaborative study is was found to be stable and suitable for use as a standard for HPL in plasma. Estimates of HPL in plasma made in different laboratories agreed more closely when expressed in terms of this reference preparation than in terms of individual laboratory standards. The reference preparation is available in ampoules (coded 73/545) which each contain an identical amount of HPL, found in the study to be approximately 850 microgram. The preparation has been established as the International Reference Preparation for HPL for immunoassay and, based on the results of the study, the content of each ampoule is defined as 850 micro International Units.


Comparison of plasma steroid and gonadotrophin profiles in spontaneous cycles in which conception did and did not occur. Luteinizing hormone (LH), follicle stimulating hormone (FSH), oestradiol and progesterone were measured in plasma from blood samples obtained daily throughout 23 menstrual cycles in a total of 18 normal women. Eight of these women were trying to conceive at the time of investigation and five succeeded. The subjects were divided into those who were not exposed to pregnancy (Group I), those who became pregnant (Group II) and those who were trying to become pregnant but failed to do so (Group III). The mean profiles of each of the four hormones were similar for the three groups studied. Statistical comparisons (using 't' tests) between Groups II and III showed that FSH concentrations were significantly lower (P less than 0.01) in the late follicular phase (Days -7 to -3 before the LH peak) in Group III. Similarly, progresterone concentrations were significantly lower (P less than 0.05) during the early luteal phase (Days +3 to +7 after the LH peak) in Group III.


Mechanisms in open-angle glaucoma.

Mechanisms in open-angle glaucoma. One hundred and nineteen eyes from 68 patients with open-angle glaucoma were provoked by means of a pilocarpine phenylephrine provocative test. In 22% the response was the same as that seen in normal eyes. In 78% the response was the same as that seen in contralateral eyes at risk to the development of closed-angle glaucoma, which do not develop a positive provocative test. The 68 patients were randomised and 34 submitted to a "dummy" provocative test. No significant change in pressure or outflow occurred. Fifty-two of the 93 eyes with an abnormal provocative test were selected for a peripheral iridectomy and reprovoked at least 6 months after operation. The results were significantly different from those obtained before operation. It was concluded that partial-angle closure could be demonstrated in some eyes with apparent open-angle glaucoma. The mechanisms involved in the production of partial-angle closure in eyes with apparent open-angle glaucoma are discussed.


The surgical treatment of open-angle glaucoma in Nigerians. The results of trabeculectomy and sclerectomy procedures for open-angle glaucoma in African Negroes are compared. Trabeculectomy produced fewer long-term complications, but otherwise there was little difference in their results. Excision of Tenon's capsule and the use of local corticosteroids postoperatively are probably significant in preventing failure of aqueous drainage from subconjunctival fibrosis.


Long-term hypotensive effect of atenolol 4% eyedrops. The effect of long-term application of 4% atenolol eye drops has been studied in patients with either glaucoma or ocular hypertension. In some patients who show a good initial response the ocular hypotensive effect gradually wears off with long-term use. This pattern of response appears to be more frequent in patients with pretreatment intraocular pressure of 25 mmHg, or greater. In combination with atenolol miotics or adrenaline show an additive effect.


Effects of pilocarpine on the morphology of the human outflow apparatus. The morphology of the outflow apparatus in human eyes which had been treated topically with either 2 or 4% pilocarpine on 4 occasions at 6-hourly intervals before enucleation was compared with an untreated control series of eyes from patients in a similar age range. In the pilocarpine-treated group the scleral spur was pulled posteriorly and internally, so that the angle formed by the scleral spur and the scleral sulcus was significantly greater in the treated than the untreated series. The change in attitude of the scleral spur produced widening of the spaces between the corneoscleral trabeculae and distension of the endothelial meshwork. It was shown from counts of giant vacuoles in the endothelium of Schlemm's canal that the incidence of giant vacuoles in the pilocarpine-treated group was greater than twice that in the controls. It would appear that pilocarpine produces alterations in the configuration of the outflow apparatus which would promote the drainage of aqueous humour.


An increased effect of pilocarpine on the pupil by application of the drug in oil. In healthy volunteers pilocarpine in an oily solution had a greater degree and duration of effect on the pupil than the same amount of drug given in aqueous solution. Blue- and brown-eyed subjects had similar degrees of miosis, but the time taken to reach peak effects was longer with the latter. It can be concluded that eye drops made with an oily solvent may provide an improvement in the treatment of glaucoma with pilocarpine.


Carotid artery disease and glaucoma.

Carotid artery disease and glaucoma. Five patients with evidence of severe bilateral carotid artery disease and increased intraocular pressure have been followed up for 3 to 12 years without the development of glaucomatous disc or field changes. Although it is frequently stated that glaucoma patients with low systemic or ophthalmic artery blood pressures show rapid progression of their eye disease, our patients show that this is not necessarily true. Other more important and largely unknown susceptibility factors determine the occurrence of glaucoma in patients with raised intraocular pressure.


The visual prognosis of the fellow eye in uniocular chronic open-angle glaucoma. The risks of damage to the visual field in a previously undamaged eye of patients with uniocular chronic open-angle glaucoma was found to be 1 out of 4 after 5 years of follow-up. The prognosis of the second eye was worse if the cup/disc ratio was  greater than or equal to 0.5, a haemorrhage was present, and the pressure was raised.


Angle-closure glaucoma secondary to posterior scleritis. This paper reports 3 patients who presented with angle-closure glaucoma secondary to posterior scleritis. Differentiation from primary angle-closure glaucoma is important, as medical treatment is markedly different while surgical treatment is not required.


Pars plana vitrectomy in the management of pupillary block glaucoma following irrigation and aspiration. Pupillary block glaucoma developed in 3 children treated with irrigation and aspiration using the Cavitron phacoemulsification system. One had a congenital cataract, 1 had blunt trauma, and 1 had a penetrating injury. The factors contributing to pupillary block included excessive retained lens material, severe post-traumatic inflammation with synechia formation in 2 cases, and the lack of iridectomy in a case requiring a membrane discission. The pupillary block was successfully treated by pars plana vitrectomy in all cases; however, vision in 1 eye was lost owing to secondary glaucoma resulting from delay in treatment and the development of 360 degrees peripheral anterior synechiae.


Symptoms without signs in outpatients attending ophthalmology clinics. Ophthalmic outpatients without physical signs have been shown, as a group, to be significantly more anxious and depressed than a control group. They also have a higher incidence of somatic complaints of a kind commonly made by patients with psychiatric 'disorder'. There was a higher incidence of past psychiatric history in the proband group, and they also gave a greater subjective assessment of recent conscious life stress.


Acyl-coenzyme A carboxylase of the free-living nematode Turbatrix aceti. 1. Its isolation and molecular characteristics. A biotin containing enzyme which carboxylates acetyl-CoA has been isolated from the nematode Turbatrix aceti and purified to homogeneity as judged by the criteria of polyacrylamide gel electrophoresis and ultracentrifugation. The enzyme has a sedimentation coefficient of 18.0 S and a molecular weight of 667 000. It is composed of four protomers having a molecular weight of 140 000 each. Each protomer, in turn, consists of two distinct polypeptide chains (molecular weights 82 000 and 58 000) and one biotinyl prosthetic group which is linked to the 82 000 peptide. The amino acid composition of the nematode carboxylase has also been determined.


Acyl-coenzyme A carboxylase of the free-living nematode Turbatrix aceti. 2. Its catalytic properties and activation by monovalent cations. A highly purified acyl-CoA carboxylase from the nametode Turbatrix aceti catalyzes the ATP, Mg2+, and HCO3- dependent alpha-carboxylation of acetyl-CoA, propionyl-CoA, and butyryl-CoA at the respective rates of 6.8, 39.7, and 9.1 mumol per min per mg. The enzyme is inhibited by avidin and sulfhydryl reagents. It is activated up to 30-fold by the monovalent cations K+, Rb+, Cs+, or NH4+, with the apparent activation constants of 11.0, 4.1, 10.0, and 6.7 mM, respectively. In the presence of K+, the apparent Km for ATP increases 5-fold, and the Km for HCO3- decreases 4-fold, whereas the Km for propionyl-CoA remains constant. Of the partial reactions, the ATP-32P exchange reaction and the carboxylation of free biotin have a nearly absolute requirement for K+. By contrast, the [14C]acetyl-CoA-malonyl-CoA exchange reaction proceeds without K+ at 80% of its maximum rate. The data indicate that K+ primarily stimulates the first half of the carboxylation reaction, i.e., the ATP-dependent carboxylation of the biotinyl residue.


Nitrogenase: the reaction between the Fe protein and bathophenanthrolinedisulfonate as a probe for interactions with MgATP. The reaction between the Fe(II) chelating agent, bathophenanthrolinedisulfonate, and the iron-sulfur cluster in the Fe protein of nitrogenase from Clostridium pasteurianum has been studied. This reaction is greatly accelerated by the presence of MgATP. Analysis of the relationship between reaction rate and concentration of MgATP supports a model in which both of two binding sites for MgATP on the Fe protein must be occupied before the protein undergoes a conformational change, allowing the iron-sulfur site to react rapidly with chelator. This model is also consistent with presently available data on equilibrium binding of MgATP to the Fe protein. MgADP inhibits the effect of MgATP on the chelator reaction in a manner which suggests that MgADP binds strongly to one of the MgATP sites and more weakly to the other. Loss of enzymic activity due to exposure to O2 or 0 degrees C is accompanied by a decrease in the ATP-specific chelator reaction. Hence, this reaction was used to estimate the concentration of active iron-sulfur centers for the purpose of computing the extinction coefficient of the Fe protein, giving the value delta epsilon 430nm(ox-red) = 6600 M-1 cm-1.


Asymmetry of chromatin subunits probed with histone H1 in an H1-DNA complex. Treatment of nucleosomes with a low concentration of sodium dodecyl sulfate removed all proteins except histone H1 from DNA, thus confirming our previous observation on sheared chromatin. No redistribution of H1 occurred during this procedure for isolation of the H1-DNA complex. The H1-DNA complex was isolated from a nucleosome monomer, doubly labeled in its protein and DNA and fractionated according to the length of DNA, and then the distribution of H1 was analyzed quantitatively. The results indicated that the monomer consisted of two subspecies, one containing 160 base pairs of DNA and one molecule of H1, and the other containing 140 base pairs of DNA and no H1. Since no monomer with two molecules of H1 was found, it is concluded that the nucleosome core has a binding site for H1 on only one side, and thus that the nucleosome is not a dyad.


Sites of in vivo phosphorylation of histone H5. Previous studies have suggested that the phosphorylation and dephosphorylation of histone H5 play an important role in controlling the condensation of avian erythrocyte chromatin. The present work locates in the polypeptide chain the major sites at which H5 is phosphorylated in vivo. The majority of the radioactivity in 32P-labeled H5 is clustered in two regions of the molecule. Nearly 50% of the 32P is found in the amino-terminal N-bromosuccinimide (NBS) peptide (residues 1-28); the remainder is confined to three phosphopeptides arising from the C-terminal half of the molecule (residues 100-200). All phosphopeptides are found in a tryptic digest of monophosphorylated H5, indicating the phosphorylation of a given site is a random event. Automatic Edman degradation of the amino-terminal fragment shows that the radioactivity is equally divided between serines at positions 3 and 7. The C-terminal phosphorylated tryptic peptides share some features with the C-terminal phosphorylation sites in H1. If, as has been postulated, the sites of phosphorylation are in or near DNA combining regions, then H5 may have two DNA combining sites. The location of the phosphorylation sites is discussed in relation to a possible mechanism for controlling chromatin condensation.


Immunological detection of O6-methylguanine in alkylated DNA. Antibodies to O6-methyldeoxyguanosine were produced in rabbits and utilized in a radioimmunoassay to detect this nucleoside at picomole levels. The specificity of the antibodies was demonstrated by the use of nucleoside analogues as inhibitors in the radioimmunoassay. The antibodies cross-reacted with O6-methylguanosine, O6-methylguanine, and O6-ethylguanosine. There was 10(4) to 10(6) times less sensitivity to inhibition by deoxyadenosine, deoxyguanosine, and guanosine than by O6-methyldeoxyguanosine. The radioimmunoassay also detected O6-methylguanine in DNA alkylated by agents known to produce O6-methylguanine, such as N'-methyl-N-nitrosourea. DNA alkylated with dimethyl sulfate, which does not produce O6-methylguanine in DNA, cross-reacted with the antibodies to a very limited extent. Such an assay system for modified nucleic acid components would be very useful in following the production, persistence, and repair of these lesions in a variety of cells and tissues treated with a broad spectrum of carcinogens and suspected carcinogens.


Kinetic analysis of cooperativity in tubulin polymerization in the presence of guanosine di- or triphosphate nucleotides. In vitro polymerization of pig brain tubulin, highly purified and deprived of microtubule-associated proteins, was followed by turbidimetry. Treatment of the data yielded the relation existing between the observed turbidity and the amount of polymer formed. This allowed a kinetic analysis, according to Oosawa's theories, of the polymerization process, which consisted of a slow spontaneous nucleation followed by the growth process. The apparent elongation rate constant was closely related to the nucleation process and exhibited a highly cooperative variation with tubulin concentration. The cooperativity was indicative of the size of the nucleus which appears to remain the same whether sheets or microtubules are formed. Magnesium ions appear to play a role in the polymorphism of tubulin polymers, the proportion of microtubules to sheets increasing with magnesium ion concentration. From kinetic experiments evidence was provided for GDP binding in competition with GTP, with a sixfold lower affinity. The tubulin-GDP complex could participate in microtubules elongation, but was not able to form nuclei. The critical concentration of tubulin in the presence of GDP was roughly twice as high as in the presence of GTP.


Influence of phallotoxins and metal ions on the rate of proteolysis of actin. The rate of proteolytic degradation of rabbit skeletal muscle actin by trypsin, alpha-chymotrypsin, and, mainly, subtilisin was followed by dual wavelength spectroscopy at 285 nm by reference at 320 nm. Phalloidin and phallacidin, two toxic bicyclic heptapeptides from the mushroom Amanita phalloides, protect F-actin against degradation by the proteolytic enzymes. G-actin, which does not combine with phalloidin when maintained in the monomeric state by working at low ionic strength, and bovine serum albumin, which also has no affinity to the toxin, are hydrolyzed at the same rates in the presence or absence of phalloidin. The proteolysis of F-actin is distinctly retarded by KCl alone, i.e., without phalloidin, whereas Mg2+ or Ca2+ as sole cations permit a rather high rate of hydrolysis. An even faster degradation of F-actin by subtilisin is observed in the presence of Mg2+ plus cytochalasin B. Adenosine diphosphate and triphosphate have no influence on the rate of the enzymatic degradation. The S sulfoxide of phalloidin, the nontoxic diastereomer of the toxic R form, exerts only a limited inhibitory effect on the enzymatic hydrolysis; secophalloidin, another nontoxic derivative, which does not bind to F-actin has practically no effect.


Complete amino acid sequence of the major component myoglobin of finback whale (Balaenoptera physalus). The complete amino acid sequence of the major component myoglobin from finback whale, Balaenoptera physalus, was determined by the automated Edman degradation of several large peptides obtained by specific cleavages of the protein. Three easily separable peptides were obtained by cleaving with cyanogen bromide at the two methionine residues and one large peptide was isolated after cleavage with (2-p-nitrophenylsulfenyl)-3-methyl-3'-bromoindolenine. More than 60% of the covalent structure was established by the sequential degradation of three of these peptides and the apomyoglobin. An additional 30% of the primary sequence was established with peptides obtained from tryptic digestion of both the apomyoglobin and the acetimidoapomyoglobin, and the final 10% of the sequence was completed after digestion of the two larger cyanogen bromide peptides with S. aureus strain V8 protease. This myoglobin differs from that of the sperm whale, Physeter catodon, at 15 positions, from that of the arctic minke whale, Balaenoptera acutorostrata, at 3 positions, and from that of the California gray whale, Eschrichtius gibbosus, at 4 positions. All of the substitutions observed in this sequence fit easily into the three-dimensional structure of the sperm whale myoglobin.


Complete amino acid sequence of myoglobin from the pilot whale, Globicephala melaena. The complete amino acid sequence of the major component myoglobin from the pilot whale, Globicephala melaena, was determined by specific cleavage of the protein to obtain large peptides which are readily degraded by the automatic sequencer. The apomyoglobin was selectively cleaved at the two methionyl residues with cyanogen bromide and the acetimidated apomyoglobin was cleaved at the three arginyl residues by trypsin. From the sequence analysis of four of these peptides and the apoprotein, over 90% of the covalent structure of the protein was obtained. The remainder of the primary structure was determined by sequence analysis of three of the tryptic peptides isolated from the central cyanogen bromide fragment after modification of its single arginyl residue with 1,2-cyclohexanedione. This myoglobin differs from that of the Black Sea dolphin at four positions and from the myoglobin of the killer whale, Pacific common dolphin, and Atlantic bottlenosed dolphin at two positions. The above differences reflect the close taxonomic relationship of these five species of Cetacea. This sequence determination was aided by the use of a Texas Instruments 980A minicomputer system which performed peak integrations for all samples subjected to amino acid analysis.