Effect of hypoxia on the sinoatrial node, atrium, and atrioventricular node in the rabbit heart. We used intracellular microelectrodes to study the effects of hypoxia on the isolated, superfused sinoatrial (SA) node, atrium, and atrioventricular (AV) node of the rabbit heart. Hypoxia decreased the rate of spontaneous impulse initiation in SA nodal fibers by decreasing the slope of diastolic depolarization. With gradually decreasing Po2, the sinus rate was reduced; concomitantly, the corrected sinus node recovery time after rapid atrial stimulation was much less affected demonstrating marked prolongation only under severe anoxic conditions. Hypoxia decreased the amplitude of action potentials of the SA node and of the AV node but not of the atrium. SA and AV nodal conduction were slowed by hypoxia; intraatrial conduction was not significantly affected. AV nodal conduction block occurred at lower atrial rates, and the effective refractory period of the AV node was prolonged. Inhomogeneity of SA and AV nodal impulse propagation often was observed in the presence of hypoxia. This was associated with concealed reentry within both nodal areas. The extracellular K+ concentration of the atrial tissue was measured with ion-sensitive microelectrodes. [K+]o remained unchanged even after prolonged periods of severe hypoxia. These results are consistent with the hypothesis that acute hypoxia predominantly inhibits slow response activity but has only little effect on the fast inward sodium current.


Effects of some components of ischemia on electrical activity and reentry in the canine ventricular conducting system. We used intracellular microelectrodes to study the electrophysiological effects of combinations of components of ischemia and their relation to the occurrence of ventricular arrhythmias in the specialized conducting system of isolated canine right ventricles. The middle area of the free wall was exposed to various test solutions in the center compartment of a three-chambered bath; the base and apex of the preparation were superfused with normal Tyrode's solution in the outer control compartments. Hypoxia (Po2 40 mm Hg), lactic acidosis (pH 6.5), and orciprenaline (10(-6) M), either alone or combined, failed to affect the action potential amplitude or the conduction velocity of the subendocardial fibers, and no arrhythmias occurred. The action potential duration and the effective refractory period were markedly prolonged by lactic acidosis. Exposure of the test regions to 15 mM K+ plus orciprenaline resulted in marked decreases in action potential amplitude and conduction velocity. Abnormalities of impulse transmission through the depressed area included high degrees of rate-dependent block, one-way block, warming-up phenomenon, and the Wenckebach phenomenon. Such conditions regularly provoked the appearance of single, sustained, or concealed reentrant depolarizations. The combined effects of hypoxia, 15 mM K+, and orciprenaline resulted in further depression of the already depressed action potential in the depolarized fibers. Our results indicate that regional increases of extracellular K+ may be the predominant factor of the components of ischemia we studied which facilitates the initiation of reentrant arrhythmias.


Regional ejection fraction: a quantative radionuclide index of regional left ventricular performance. Radionuclide measurements of regional left ventricular ejection fraction were evaluated as a quantitative index of regional left ventricular function. Left ventricular regional ejection fractions were derived from background-corrected, time-activity curves in 43 patients assessed by both gated equilibrium radionuclide angiocardiography and left ventricular contrast angiography. From a single, modified left anterior oblique projection, the regional change in background corrected counts was determined in each of three anatomic regions. The normal range for regional radionuclide ejection fraction was determined in 10 patients with normal contrast ventriculograms and without obstructive coronary artery disease at coronary arteriography. Regional ejection fraction was compared with percent segmental axis shortening and extent of akinetic segments in corresponding regions of the contrast ventriculogram. Radionuclide and roentgenographic methods were in agreement as to the presence or absence of abnormal wall motion in 83 of 99 left ventricular regions (84%) in 33 patients evaluated prospectively. Comparison of regional ejection fraction demonstrated significant differences between regions with roentgenographically determined normokinesis (75 +/- 3%, mean +/- SEM), hypokinesis (44 +/- 3%, p less than 0.0005) and akinesis (24 +/- 5%, p less than 0.005). We conclude that the left ventricular regional ejection provides a reliable quantitative assessment of regional left ventricular performance.


Usefulness and limitations of thallium-201 myocardial scintigraphy in delineating location and size of prior myocardial infarction. In order to evaluate the usefulness of thallium-201 (201TI) myocardial scintigraphy in delineating the location and size of prior myocardial infarction, 32 patients were evaluated at a mean of 7 +/- 2 months after infarction with a 12-lead ECG, resting 201TI myocardial scintigram, biplane left ventriculogram and coronary angiograms. From the left ventriculogram, asynergy was quantified as percent abnormally contracting segment (% ACS), the percent of end-diastolic circumference which was either akinetic or dyskinetic. Using a computerized planimetry system, we expressed 201TI perfusion defects as a percentage of total potential thallium uptake. Of 21 patients with ECG evidence of prior transmural infarction, a 201TI defect was present in 20 (95%), and angiographic asynergy was present in all 21 (100%). The site of prior infarction by ECG agreed with the 201TI defect location in 24 of 32 patients (75%) and with site of angiographic asynergy in 23 of 32 patients (72%). Scintigraphic defects were present in only four of 10 patients (40%) with ACS less than or equal to 6%, but scintigraphic defects were found in 20 to 22 patients (91%) with ACS greater than 6% (p less than 0.01). Thallium defect size correlated marginally with angiographic left ventricular ejection fraction (r = -0.60) but correlated closely with angiographic % ACS (r = 0.80). Thallium defect size was similar among patients with one-, two-, or three-vessel coronary artery disease (greater than or equal to 70% stenosis), but thallium defect size was larger in patients with electrocardiographic evidence of transmural infarction (p less than 0.01) or pulmonary capillary wedge pressure greater than 12 mm Hg (p less than 0.001). Thus, resting 201TI myocardial scingigraphy is useful in localizing and quantifying the extent of prior myocardial infarction, but is insensitive to small infarcts (ACS less than 6%).


Effect of left ventricular akinesis on cardiac performance. Experimental study using a new model. The understanding of left ventricular failure and cardiogenic shock after myocardial infarction has been facilitated by a two-component model proposed by Swan et al. which views the left ventricle as consisting of a clearly defined infarcted portion and a normally functioning remainder. Although appealing, this model is difficult to substantiate experimentally. We describe a new experimental preparation in which the infarct is stimulated by replacing part of the left ventricular wall with an inert patch of Dacron material. In 18 dogs studied after replacing varying amounts of left ventricular contractile mass with noncontractile patches, the left ventricular end-diastolic pressure rose in proportion to the size of the patch. Contractility was unchanged, and overall left ventricular pump function was normal. These data support the conceptual model. The experimental preparation is applicable to other studies of left ventricular akinesis.


A mathematical model of the dynamic geometry of the intact left ventricle and its application to clinical data. In this paper we examine the relations that may exist between the geometric variables most frequently used to describe left ventricular contraction. The left ventricle is represented by a thick-walled cylinder contracting both radially and longitudinally. For this model, wall thickening, mid-wall radius shortening and longitudinal axis shorteining can be shown to be uniquely related during contraction, whereas it can be demonstrated that internal radius shortening is not uniquely related to these variables, but is also determined by the specific geometry of the cylinder, expressed in terms of the mid-wall radius-to-wall thickness (R/h) ratio of the cylinder. Detailed analysis of the same variables in 44 normal subjects, 32 patients with aortic stenosis and 54 patients with valvular regurgitation (33 aortic and 21 mitral), strongly suggests that the same relations are also clinically applicable. For instance, ventricular longitudinal axis shortening can be estimated with some accuracy from the standard M-mode echocardiogram. Also, wall thickening can be viewed as the direct reflection of the shortening that occurs in the circumferential and longitudinal directions, whereas internal radius shortening is significantly influenced by the R/h ratio of the ventricle, a consideration which becomes important when analyzing results in patients with left ventricular hypertrophy.


Prospective evaluation of intrahisian conduction delay. We prospectively evaluated 46 patients who had intrahisian conduction delay. Twenty-three had a split His potential and 23 had a prolonged HV interval with a normal QRS complex. In those with a split His, the interval between the two His potentials averaged 32.7 msec (range 9--90 msec); in nine patients this split His was demonstrated only by atrial pacing. The 20 patients from this group with 1:1 atrioventricular conduction have been followed for an average of 18.1 months (range 2--48 months). All are alive. Three have had syncope, but Holter monitoring revealed no bradyarrhythmias. In the 23 patients with a narrow QRS and prolonged HV interval, the HV interval averaged 73.7 msec (range 57--180 msec). Twelve of these patients received pacemakers at the time of the His bundle study, six had symptomatic atrioventricular block and five had symptomatic sinus pauses. The 11 patients who did not receive pacemakers have been followed for an average of 15.1 months (range 2--44 months). In three with recurrent syncope and five with dizziness, monitoring has revealed no bradyarrhythmias. One patient died from a myocardial infarction without arrhythmias. Further prospective evaluation of patients with intrahisian conduction delay without documented bradyarrhythmias is needed, but with follow-up averaging 17 months and up to 4 years, patients with intrahisian conduction delay and without documented bradyarrhythmias appear not to require prophylactic permanent pacemakers to decrease morbidity or mortality.


Dopamine beta-hydroxylase and plasma renin activity in patients with low-, normal-, and high-renin essential hypertension. The relationship of serum dopamine-beta-hydroxylase (DBH), plasma renin activity (PRA) and urinary catecholamines (IU catechols) in various forms of essential hypertension (EHT) (low, normal and high renin) was evaluated. Eighty-four predominantly white, young (37 +/ 8 years (SD)), mildly hypertensive patients (diastolic pressure 93 +/- 4 mm Hg (SD)) continued their regular diet and received no medications. Thirteen patients had low-renin, 64 had normal-renin, and seven had high-renin EHT. DBH, total IU catechols and urinary norepinephrine were not different between these renin subgroups. DBH was significantly lower in all hypertensives (55.6 +/- 36 IU) and in the low-renin subgroup (46 +/- 30 IU) compared with normal subjects (68 +/- 35 IU) (p less than 0.01). However, the DBH range was so broad that an individual DBH value did not distinguish EHT from normals. After a baseline period, patients were randomly assigned to receive chlorthali done 50 mg q.a.m. or placebo in a double-blind study. In the chlorthalidone group 1 month after therapy, the diastolic pressure decreased, PRA increased, and total IU catechols and urinary norepinephrine increased. Serum DBH did not change during diuretic therapy. A significant correlation could not be shown between pretreatment DBH and the changes in PRA and IU catechols before and after diuretics for all treated EHT patients. However, within the normal PRA EHT subgroup receiving chlorthalidone, the one-third of patients with lowest pretreatment DBH levels (n = 10) were compared with the one-third of patients with the highest pretreatment DBH values (n = 10). The lower DBH patients showed significantly less change in PRA (delta PRA = 2.9 +/- 1.8 ng/ml/hr) compared with the higher DBH patients (delta PRA = 8.2 +/- 1.6; P less than 0.05). In some EHT patients, DBH levels may be related to PRA response to diuretic therapy.


Right atrial myxoma: unusual clinical presentation and atypical glandular histology. A 57-year-old black female presented with a 1-month of right-sided congestive heart failure and clinical evidence of pulmonic and tricuspid valvular stenosis and insufficiency. The echocardiographic examination and ventriculography demonstrated a large right atrial tumor interfering with the function of both right-sided valves. The patient underwent successful surgical resection of the tumor. Histologically, the tumor had cellular areas typical of myxoma, as well as glandular areas, a feature which has been described very rarely in this lesion. Electron microscopy of the glandular zones, which has never been reported previously, shown cells having essential homology with the usual myxoma elements. The atypical histopathology of this lesion supports the theory that atrial myxomas are true neoplasms, and are not derived from unusually organized mural thrombi.


Congenital coronary arteriovenous fistula. Report of 13 patients, review of the literature and delineation of management. Thirteen new patients and 174 patients previously reported with coronary arteriovenous fistula (CAVF) were reviewed to delineate the course and management of CAVF and to clarify the role of surgical ligation in the young asymptomatic patient. Patients were grouped according to age: 99 patients (four new and 95 reported) were less than 20 years old and 88 (nine new and 79 reported) were greater than or equal to 20 years old. Of those under 20 years of age, 19% had preoperative symptoms or CAVF-related complications, including congestive heart failure (CHF) in 6%, subacute bacterial endocarditis in 3% and death in one patient. Seventy-six patients younger than 20 years old had CAVF ligation with only one significant complication. In contrast, 63% of the older group and all of our nine older patients had preoperative symptoms or complications, including CHF in 19%, SBE in 4%, myocardial infarction (MI) in 9%, death in 14% and fistula rupture in one patient. Of the 43 ligated older patients, 23% had surgical complications, including MI in three and death in three. Mean pulmonic-to-systemic flow in the entire group was 1.6:1 and did not differ significantly in those with or without symptoms or complications. One of our patients and one previously reported had spontaneous CAVF closure. In summary, early elective ligation of CAVF is indicated in all patients because of the high incidence of late symptoms and complications and the increased morbidity and mortality associated with ligation in older patients.


Antiarrhythmic drug therapy in survivors of prehospital cardiac arrest: comparison of effects on chronic ventricular arrhythmias and recurrent cardiac arrest. We studied the long-term effects of membrane-active antiarrhythmic agents on chronic ventricular arrhythmias in patients who have survived prehospital cardiac arrest. Among 16 patients treated with a dose-adjusted, plasma level-monitored antiarrhythmic regimen, eight have survived for longer than 12 months and eight have had recurrent cardiac arrests (RCAs). Monthly Holter monitor tapes (HM) recorded during the 4 months before the eight RCAs were compared with monthly HM tapes matched for time of entry and duration of follow-up in the eight patients who did not have RCAs. Transient or persistent complex ventricular ectopic depolarizations (VEDs) have been recorded on 47 of the 63 monthly HM tapes (75%). The difference between VEDs in the RCA patients (mean 153 VEDs/hr, median 19 VEDs/hr) and VEDs in the patients who have not had RCA (mean 122 VEDs/hr, median 8 VEDs/hr) was not significant (p less than 0.2); nor was there a predictable relationship between therapeutic plasma levels of antiarrhythmic agents and the frequency and complexity of chronic asymptomatic VEDs (therapeutic levels--mean 104 VEDs/hr, median 6 VEDs/hr; subtherapeutic levels--mean 184 VEDs/hr, median 21 VEDs/hr). Differences were not significant (p greater than 0.1). In contrast, all eight RCA patients had unstable plasma levels (21 of 31 determinations subtherapeutic) while six of the eight patients who have not had RCA had consistently therapeutic levels (p less than 0.01). Thus, adequate plasma levels of antiarrhythmic agents may protect against RCA, despite failure to suppress VEDs predictably. The apparent dissociation between predictable suppression of chronic VEDs and protection against RCA suggests that clinical effectiveness of these agents may not be best measured by their effect on chronic VEDs.


Effect of verapamil in infants with paroxysmal supraventricular tachycardia. Twenty-nine consecutive spontaneous attacks of paroxysmal supraventricular tachycardia (PSVT) in 14 infants (mean age 4.4 months) were treated with verapamil. No infant had associated heart disease. Verapamil 1-2 mg i.v was administered over 30 seconds. The dosage varied according to the weight of the infant. Within 60 seconds sinus rhythm was obtained in 28 instances (96.5%). No significant complications were observed. The high effectiveness, rapid action and lack of undesirable side effects observed in this series suggest that verapamil is the drug of choice in the treatment of PSVT in infants without underlying heart disease.


The cardiac conduction system in situs ambiguus. The cardiac specialized conduction tissue was studied by serial sectioning in 13 cases of situs ambiguus. In four cases of right isomerism, we found paired sinus nodes in relation to a crista terminalis, and in each case a sling of conduction tissue between two atrioventricular nodes was present regardless of the ventricular morphology or cardiac position. In the cases with left isomerism, the sinus node was hypoplastic and abnormally located. We saw two types of atrioventricular conduction systems. In the three cases in which the morphologically right ventricle lay to the right of the morphologically left ventricle (presumed d-loop), a single atrioventricular bundle arose from a normally located atrioventricular node. In the five cases in which the morphologically right ventricle lay to the left of the morphologically left ventricle (presumed l-loop) and in the one case with a univentricular heart, paired atrioventricular nodes were present, linked or potentially linked by a sling of conduction tissue.


Echocardiographic estimation of ventricular hypoplasia in complete atrioventricular canal. Echocardiograms from 10 patients with complete atrioventricular canal (CAVC) were compared with autopsy specimens to determine the capabilities of echocardiography in identifying patients with ventricular hypoplasia. On the basis of echographic ventricular size, patients could be divided into three groups: 1) "balanced" CAVC patients had both increased right and left ventricular end-diastolic dimensions (RVED and LVED) and an increased RVED/LVED ratio; 2) "dominant left ventricular" CAVC patients had an increased LVED and small or normal RVED and a diminished RVED/LVED ratio; 3) "dominant right ventricular" CAVC patients had an increased RVED, but small LVED, and increased RVED/LVED. There was complete agreement between echographic ventricular dominance and pathologic findings. This study demonstrates that echocardiography may be valuable in assessing ventricular dominance in the presence of CAVC.


Autonomic dysfunction in women with mitral valve prolapse syndrome. Autonomic cardiovascular regulation was evaluated in 35 women, 19 with mitral valve prolapse and 16 healthy controls. Heart rate responses to the diving reflex and to phenylephrine infusion were diminished in patients. Noninvasive measures of cardiac output, heart rate, blood pressure, forearm flow and leg volume during lower body negative pressure (LBNP) showed that patients had less lower extremity pooling of blood and had lower forearm conductance. Blood pressures during LBNP rose or remained unchanged despite decreases in cardiac output of 20--25%. These data indicate that mitral valve prolapse patients have an increased venous and arterial vasoconstrictor activity. Cardiac output at rest and echocardiographic indices of contractility were normal. Patients with a history of significant ventricular arrhythmias had higher heart rates and lower forward stroke volumes than the other patients or controls. The combined data demonstrate autonomic dysfunction in women with the mitral valve prolapse syndrome and suggest decreased parasympathetic, increased alpha- and normal beta-adrenergic tone and responsiveness.


Mitral valve closure in atrial flutter.

Mitral valve closure in atrial flutter. 12 patients who had atrial flutter without clinical, echocardiographic or angiographic evidence of aortic insufficiency were studied with simultaneous echo- and phonocardiograms. In patients with high-grade atrioventricular (AV) block, the mitral valve opened and closed with each flutter wave. Of seven patients, two had persistent and five had intermittent early mitral valve closure before QRS inscription. In five patients (three with 2:1 AV block) the mitral valve closed on time. In one patient with a mitral valve prosthesis, echocardiography and cinefluorography demonstrated closure during mid-diastole, with reopening in late diastole after a flutter wave. Final valve closure occurred before the onset of the QRS, and each closure was associated with a click. Simultaneous phonocardiographic analysis in these patients demonstrated that the first heart sound intensity was inversely related to the degree of mitral valve preclosure. This relationship was independent of the length of the RR interval. Thus, atrial flutter independent of any other cause of abnormal hemodynamics may produce early mitral valve closure. The echocardiographic finding of premature mitral arrhythmias, may not have the same diagnostic or prognostic significance previously described in patients with sinus rhythm and normal AV conduction.


Hemodynamic factors influencing arterial hypoxemia in massive pulmonary embolism with circulatory failure. Arterial hypoxemia is a common finding in acute pulmonary embolism, and its severity is generally assumed to be proportional to the extent of pulmonary artery obstruction. We studied blood gases (during room air breathing and 100% oxygen breathing) and hemodynamic data is seven patients with massive pulmonary embolism and circulatory failure. All measurements were made before and 30 minutes after medical therapy of shock. We observed that a low cardiac output state can result in a misleading improvement in arterial oxygenation during massive pulmonary embolism, and that an improved circulatory status resulting from medical therapy (including inotropic drug infusion with or without blood volume expansion) can paradoxically increase arterial hypoxemia. We conclude that severity of arterial hypoxemia may not reflect the severity of pulmonary artery obstruction in acute pulmonary embolism if shock is present.


Echocardiographic evaluation of ventricular septal aneurysms. The spontaneous closure of ventricular septal defects is frequently associated with septal aneurysm formation. In this paper we discuss the M-mode and two-dimensional echocardiographic findings in nine children with aneurysms of the ventricular septum in association with ventricular septal defects. In all patients the diagnosis was confirmed by angiography. The ventricular septal aneurysms were detected by both M-mode and two-dimensional echocardiography. With M-mode echocardiography, septal aneurysms could be recognized by a pattern of multiple systolic echoes within the right ventricle. With two-dimensional echocardiography, the protrusion of the septal aneurysm into the right ventricle could be seen from several views and the location and the relative size of the aneurysm assessed. Echocardiographic techniques useful in the detection of ventricular septal aneurysms are discussed and examples presented.


Circadian variation of exercise capacity in patients with Prinzmetal's variant angina: role of exercise-induced coronary arterial spasm. Thirteen patients with Prinzmetal's variant angina performed treadmill exercise tests in the early morning and in the afternoon of the same day. The attacks with ST elevation were induced repeatedly in all 13 patients in the early morning, but in only two patients in the afternoon. Propranolol did not suppress the exercise-induced attacks in all 13 patients. Diltiazem suppressed the attacks in all 13 patients and phentolamine in eight of the nine patients. Coronary arteriograms demonstrated that spasm occluding completely or almost completely the large coronary artery supplying the area of myocardium showing ST elevation appeared during the attacks and disappeared along with the attacks after nitroglycerin administration in all four patients in whom the attacks were induced by arm exercise in the catheterization laboratory. We conclude that there is circadian variation of exercise capacity in patients with Prinzmetal's variant angina caused by coronary arterial spasm induced by exercise in the early morning but not in the afternoon.


Coronary arterial spasm as a cause of exercise-induced ST-segment elevation in patients with variant angina. Four patients with variant angina pectoris exhibited reproducible exercise-induced chest pain and ST-segment elevation. Coronary arterial spasm was documented with arteriography during exercise-induced ST-segment elevation (three patients) or after intravenous administration of ergonovine maleate (one patient). Our observations show that in patients with variant angina exercise can trigger coronary arterial spasm, thus inducing anginal pain and ST-segment elevation.


Uric acid: a risk factor for coronary heart disease? The association between serum uric acid and the prevalence of ECG abnormalities was analyzed for 24.997 employed men and women, white and black, age 18--64 years, from the Chicago Heart Association (CHA) Detection Project in Industry. In addition, the relationships between uric acid and 5-year mortality from all causes, from cardiovascular diseases (CVD), and from coronary heart disease (CHD) were analyzed for 7804 white men and women age 45--64 years from this study and 967 white men age 44--63 years from the Chicago People's Gas Company Study. For men, the association between uric acid and the prevalence of ECG abnormalities and with mortality appear to be secondary to associations between uric acid and other risk factors. For women, however, the associations could not be explained by other risk factors.


Comparison of cardiovascular responses to static-dynamic effort and dynamic effort alone in patients with chronic ischemic heart disease. Thirty men, mean age 55 years, known to have treadmill-induced ischemic ST-segment depression, performed static and dynamic effort, i.e., forearm lifting and treadmill exercise, separately and combined. Static effort was sustained at 20%, 25% or 30% of maximal forearm lifting capacity. Two symptom-limited treadmill tests, one with and one without added static effort, were performed on each of two visits. Compared with dynamic effort alone, combined static-dynamic effort decreased treadmill work load and increased heart rate, systolic blood pressure and rate-pressure product at the onset of ischemic ST-segment depression or angina pectoris: 7.1 +/- 0.4 vs 8.0 +/- 0.5 (SEM) multiples of resting oxygen consumption (mets), estimated; 141 +/- 3 vs 134 +/- 3 beats/min; 170 +/- 4 vs. 162 +/- 4 mm Hg and 239 +/- 8 vs 218 +/- 9 (p less than 0.001). The prevalence of angina pectoris was significantly less with combined static-dynamic effort than with dynamic effort alone. Static effort causes a resetting of the threshold at which ischemic abnormalities appear during dynamic effort.


Impaired maximal rate of left ventricular relaxation in patients with coronary artery disease and left ventricular dysfunction. It has been suggested that the rate of left ventricular (LV) relaxation is related to the inotropic state, end-systolic fiber length and peak LV pressure, but little information is available regarding the rate of LV relaxation in patients with coronary artery disease (CAD) and LV dysfunction. To assess the rate of LV relaxation we obtained high-fidelity LV pressure measurements with manometer-tip catheters in 39 patients. The signal was analyzed by a digital computer to yield the maximal rate of pressure rise (pos dP/dt) and the maximal rate of pressure fall (neg dP/dt). Selective coronary arteriography and biplane LV angiography with determination of LV volumes, ejection fraction (EF) and percent abnormally contracting segments (ACS) when present, were performed in all patients. In 10 patients with normal LV function (EF greater than 0.50, no asynergy) mean neg dP/dt (2074 +/- 121 mm Hg/sec) was significantly (p less than 0.01) greater than in 29 patients with CAD and LV dysfunction (1695 +/- 66 mm Hg/sec). In nine patients with LV dysfunction and EF less than 0.35, mean neg dP/dt was reduced to 1405 +/- 107 mm Hg/sec, significantly (p less than 0.01) lower than in patients with normal LV function. Neg dP/dt correlated well with pos dP/dt (r = 0.75), with EF (r = 0.74), and with ACS (r = -0.74), and less well with LV end-systolic volume (r = 0.67). There was very poor correlation between neg dP/dt and peak LV pressure (r = 0.30). These data suggest that the rate of LV relaxation, as assessed by neg dP/dt, is impaired in patients with CAD and LV dysfunction, and the extent of impairment is related to the severity of the dysfunction as determined hemodynamically by pos dP/dt, and angiographically by EF and ACS. In these patients the maximal rate of LV relaxation is inversely related to LV end-systolic volume, and is not related to peak LV pressure.


Quantitative left ventricular wall motion analysis: a comparison of area, chord and radial methods. We were interested in divising a relatively simple quantitative technique that could be used on a routine clinical basis for wall motion analysis. Three quantitative methods of left ventricular (LV) regional analysis were compared in the 30 degrees right anterior oblique and 60 degrees left anterior oblique projection. The control group consisted of 17 patients with qualitatively normal LV wall motion; the abnormal group comprised 17 patients with at least one region of severe, qualitative wall motion abnormality. Normal regional values were determined for area, chord and radial methods by applying the techniques to the ventriculograms of the control group. Each technique was then applied to the abnormal group's ventriculograms to determine the percentage of qualitatively abnormal regions not detected by each method. The area method had the lowest failure rate (p less than 0.001) and the best separation of measured normal and abnormal regions' ejection changes (p less than 0.001), and best reflected symmetric uniform motion of the ventricular silhouette. We conclude that the area method, of the techniques examined, was best for the quantitative analysis of LV wall motion abnormalities.


Evaluation of steroid laboratory tests and adrenal gland imaging with radiocholesterol in the aetiological diagnosis of Cushing's syndrome. Basal values of the urinary excretion of 17-oxogenic steroids and serum levels of cortisol were not satisfactory in the differentiation of 'suspected' subjects from patients with true Cushing's syndrome. With an RIA method for serum cortisol determination, the overnight dexamethasone suppression test provided the most reliable single test in establishing adrenocortical hyperfunction. Thirty-five normal subjects, fifty-nine obese patients, thirteen 'suspected' patients, and thirteen patients with disease states other than Cushing's syndrome had suppressed values below 4.0 microgram/100 ml. None of the ten patients with Cushing's syndrome had a cortisol concentration less than 16.3 microgram/100 ml. Adrenal gland scintigraphy after radiocholesterol injection is a more valuable tool than the metyrapone test and the high-dose dexamethasone suppression test in the localization and differential diagnosis of adrenocortical lesions causing Cushing's syndrome. It obviates the need for angiographic procedure in the localization of adenomas. It is a reliable technique for identifying functioning adrenal remnants. We therefore propose a schedule for studying patients with suspected adrenocortical hyperfunction.


Thyrotropin, free and total triiodothyronine, and thyroxine in serum during surgery. Changes in free and total thyroxine (T4), triiodothyronine (T3) and thyroid stimulating hormone (TSH) in serum were measured before, during, and for nine days after uncomplicated abdominal surgery in eight patients. The results showed a pronounced fall in total as well as in free T3 levels, amounting to 50% in both variables on the first postoperative day, and returning towards preoperative levels on the seventh and ninth day. Apart from an increase during surgery, free T4 levels were constant in the whole period despite a slight postoperative decrease in total T4. The TSH level fell about 80% within the first 24 postoperative h, but returned to the preoperative level thereafter. These results suggest a suppression of both T3 and TSH production during the pre- and early postoperative period.


Ethanol induced secretion of calcitonin in chronic renal disease. Whisky (25-50 ml) increased plasma levels of immunoreactive calcitonin (iCT) in seventeen of nineteen patients with chronic renal failure. The effect was greater in patients with high levels of iCT than in those with normal levels. Changes in plasma iCT were not related to changes in calcium, phosphate or immunoreactive gastrin, but were inhibited by the prior administration of propranolol.


Selective venous sampling in the diagnosis and localization of phaeochromocytoma. Plasma noradrenaline levels were measured at several sites in the systemic venous system by selective catheterisation in ten hypertensive patients in whom phaeochromocytoma was suspected on clinical or biochemical grounds. Four patients had localized noradrenaline elevation and the diagnosis of phaeochromocytoma was confirmed at operation. The remaining six patients demonstrated no localized elevation of noradrenaline and there has been no evidence of a tumour on follow up. The technique allows the diagnosis and accurate localization of phaeochromocytoma and is useful in excluding the tumour in patients with essential hypertension.


Growth hormone release inhibitory hormone-like immunoreactivity in pancreas and gut in streptozotocin diabetes in the rat and response to insulin administration. In streptozotocin diabetes in the rat, growth hormone release-inhibitory hormone-like immunoreactivity (GHRIH-LI) content of pancreas, gastric antrum and colon was increased. Insulin therapy significantly lowered the increased pancreatic GHRIH-LI content but did not affect that of the gastric antrum and colon at the dosage used. The relevance of these findings in relation to pancreatic and gastrointestinal function in diabetes awaits clarification.


Effect of age on plasma androstenedione concentration in oophorectomized women. Plasma androstenedione concentration was measured in 92 oophorectomized women in the age range 33 to 76 years. Although this concentration was significantly inversely correlated with age, the data suggest a discrete change in the first half of the sixth decade rather than a continuous fall.


Thyroid hormone levels during glucose tolerance test in euthyroid subjects. Twelve normal, healthy, clinically and biochemically proven euthyroid volunteer subjects (age 19-35) were administered a standard glucose tolerance test (100 g glucose orally) and thyroxine (T4), triiodothyronine (T3) and reverse triiodothyronine (rT3) levels were determined by specific radioimmunoassays to determine the acute effect of glucose and insulin on peripheral monodeiodination of thyroxine. The fasting levels of T4, T3, rT3 and free thyroxine were 82.4 nmol/l, 1.7 nmol/l, 0.52 nmol/l, and 0.22 nmol/l, respectively, and these levels were unchanged during the 3 hours post-glucose load. The rise and fall of glucose and insulin levels were typical of the standard responses normally observed in the glucose tolerance test. The variations in insulin and glucose levels were not correlated with thyroid hormone concentrations at any interval during the test. It is therefore concluded that dietary glucose does not acutely cause shifts in peripheral monodeiodination of thyroxine in healthy euthyroid subjects.


Seminal immunoreactive prolactin before and after vasectomy. Seminal fluid was assayed for prolactin by radioimmunoassay in eleven healthy males 8-12 weeks following vasectomy. The results were compared with those obtained in 34 age matched subjects prior to undergoing vasectomy. The mean values (+/- 1 SD) for prolactin were similar (postvasectomy = 11.4 +/- 3.2 ng/ml, prevasectomy = 12.7 +/- 6.1 ng/ml) and there was no statistically significant difference (t = 0.66, P = greater than 0.05). This study shows that prolactin is found in secretions of the prostate and/or seminal vesicles.


Inhibition of neutrophil chemotaxis in association with experimental angioedema in patients with cold urticaria: a model of chemotactic deactivation in vivo. Deactivation is a phenomenon in which leucocytes exposed in vitro to a chemotactic factor in the absence of a concentration gradient are rendered relatively unresponsive to stimulation by a subsequent chemotactic gradient. In patients with idiopathic cold-induced urticaria, the elicitation of a local experimental angioedematous lesion causes the release of two chemotactic principles previously shown to deactivate leucocytes in vitro, high molecular weight neutrophil chemotactic factor (HMW-NCF) and eosinophil chemotactic factor of anaphylaxis (ECF-A), into the venous circulation draining the challenged extremity. However, biopsy specimens of lesional skin sites obtained for up to 24 hr show no infiltration of cells. For this reason, the in vitro chemotactic responsiveness of neutrophils to the chemotactic factor HMW-NCF and C5 fragments were assessed in three patients at various times after experimental challenge. Leucocytes from venous effluent draining an experimentally-induced angioedematous lesion were markedly impaired in their chemotactic responsiveness to both chemotactic factors 5 min after challenge, while cells taken from an unchallenged extremity at the same time responded normally. Cells from both arms were equally impaired in their responsiveness 1 hr later, thereby demonstrating that the chemotactic defect becomes systemic. The acquired defect was dissipated 4 hr after challenge. These data suggest that deactivation may occur in vivo and may alter host responsiveness in states where chemotactic factors are released into the circulation.


The use of antibody-coated liposomes as a target cell model for antibody-dependent cell-mediated cytotoxicity. A simple model system was developed for antibody-dependent cell-mediated cytotoxicity (ADCC) using antibody-coated synthetic membranes (liposomes) as a target cell model. A synthetic hapten, dinitrophenyl-phosphatidylethanolamine (DNP-PE), was incorporated into fluorophore-quencher-loaded liposomes and the latter were coated with pure anti-DNP antibodies. Normal spleen lymphocytes were capable of binding and subsequently lysing these liposomes. This process is dependent upon the presence of an intact (Fc-containing) IgG molecule and independent of exogenous serum complement. The effector lymphocytes are nylon non-adherent, devoid of Thy-1 antigen and present in nude mice, suggesting an identity with K (Fc receptor positive) lymphocytes. These studies indicate that liposomes may be used as a model to study the requirements for the binding and lysis of target cells in this cell-mediated cytotoxic system.


Late treatment of murine lupus erythematosus with dactinomycin (actinomycin D). I. Course and longevity. Dactinomycin treatment a of group of (NZB X NZW)F1 hybrid female mice was delayed until the age of 6-6 1/2 months, by which time the immune complex disease was well established. Three animals of the original twenty-eight had already died, ten had heavy proteinuria and a few were oedematous. The dactinomycin dose was 3.5 microgram per day, which was suspended when significant weight loss occurred. Twelve of the thirteen experimental mice were alive at 12 months of age, eleven at 15 months, but only eight by 20 months, whereas all twelve control animals had died by the age of 11 months. These results and the supporting data on body weight and renal function indicate that dactinomycin can at least arrest the disease process and may improve it. The mechanism is not known, but it may be the result of a reduced availability of DNA or an alteration in its properties following combination with dactinomycin.


Effects of Corynebacterium parvum and BCG therapy on immune parameters in patients with disseminated melanoma a sequential study over 28 days. I. Changes in blood counts, serum immunoglobulins and lymphoid cell populations. The effects of a single immunization of melanoma patients with BCG or C. parvum on the blood counts, serum immunoglobulin levels and lymphoid subpopulations were followed by multiple assays over 28 days. C. parvum produced a decrease in the white cell count, lymphocyte count and lymphoid T and sIg+ cell numbers, which recovered within 1 week; BCG did not produce such a marked depression. Both agents were associated with increases in T cell numbers and lymphocyte PHA blastogenesis after the first week; these declined to pre-immunization values by 3-4 weeks. The sIg-bearing cell subpopulation also increased after BCG. Different methods of expression the results were compared and the difficulties of immunological monitoring are discussed.


Immune complexes in peripheral blood polymorphonuclear leucocytes of patients with Raynaud's phenomenon. Phagocytosed immune complexes in polymorphonuclear (PMN) leucocytes of sixty-nine patients with Raynaud's phenomenon were studied by scoring the cells for IgG and complement inclusions. The results were compared with the degree of vasospasm, as measured by photoelectric plethysmography of the fingers after cooling. Median IgG and complement scores of PMN cells were significantly elevated in patients with Raynaud's phenomenon when compared with those of the control group (P less than 0.01). Patients with a positive (n = 35) or a strongly positive (n = 11) plethysmographic test showed significantly higher median IgG and complement scores than those with a negative plethysmorgraphic test (n = 23). They also showed elevated IgG and complement scores in a greater proportion (89 and 100%, respectively, vs 48%).Thus, a positive relationship was shown to exist between the degree of vasospasm and the levels of phagocytosed immune complexes in circulating PMN leucocytes. In secondary Raynaud's phenomenon high levels of phagocytosed immune complexes were found. In primary Raynaud's, patients with some clinical or laboratory signs of an auto-immune disease (n = 12), who were classified as "suspected secondary", had higher IgG and complement scores than those without such signs (n = 37). This suggests that the test for immune complex detection may distinguish patients with connective tissue disease-associated Raynaud's phenomenon from those with truly primary Raynaud's, in an early stage of the disease. The clinical and patho-physiological implications of these findings with regard to the Raynaud phenomenon are discussed.


Levels of the serum amyloid A protein (SAA) in normal persons of different age groups. Serum amyloid A (SAA) has been implicated by three independent studies to increase in concentration with ageing. The present study measured SAA concentration in 395 samples from 302 healthy individuals ranging in age from 21 to 100 years. The average SAA concentration was 20 microgram/ml, with only five serum samples falling below 5 microgram/ml. SAA concentrations are expressed in terms of cross-reactivity of purified, denatured SAA with anti-AA antibodies, rather than the purified, denatured amyloid fibril protein AA from tissues, which has been used in the past. No age-related increase in SAA concentration was observed in the present study. The average SAA concentration in these normal, healthy individuals was almost a hundred-fold less than values measured in acute phase human serum in a separate study with the same reagents.


Tests for Dane particles in serum concentrates of HBsAg positive hemodialysis patients. The present study was undertaken to assess the infectivity of sera from HBsAg positive hemodialysis patients by measuring HBeAg, DNA polymerase activity and Dane particle associated HBcAg. Of 33 sera tested 25 were positive for at least one of these tests for Dane particles, indicating that most HBsAg positive hemodialysis patients are highly infectious. The demonstration of DNA polymerase activity in serum concentrates was proven to be the most sensitive assay for the detection and quantitation of Dane particles in serum. We conclude from our results that HBsAg positive hemodialysis patients should be treated in separate units and be served by staff who are either anti-HBs positive or HBsAg carriers.


Fibrinous pericarditis and fibrinolysis in chronic dialysis patients. During a four year period 6 patients from the total of 120 on home dialysis developed pericarditis with effusions. Plasma fibrinolytic activity, measured by euglobulin clot lysis time, was significantly reduced in these patients compared with either normal controls or dialysis patients without pericarditis. These dialysis patients without pericarditis as a group tended to have reduced plasma fibrinolytic activity compared with controls, but the difference was not significant. It is suggested that a reduction in the body's fibrinolytic activity may be a factor in the development of fibrinous pericarditis in chronic renal failure.


Cyclophosphamide alone in the treatment of adult patients with minimal change glomerulonephritis. Eight adult patients with the nephrotic syndrome due to "minimal change" glomerulonephritis have been treated with cyclophosphamide alone. The effects of therapy have been compared with a similar group of patients treated with conventional diuretic therapy. Complete remission was achieved in seven of the cyclophosphamide treated patients as compared to only two spontaneous remissions in the untreated group. After a mean follow up period of 6 years none of these 9 patients relapsed. The eighth patient treated with cyclophosphamide remitted spontaneously 21 months after stopping cyclophosphamide and relapsed 36 months later. No serious side effects were encountered in the treated patients. The results suggest that cyclophosphamide is an effective agent in the management of adults with the nephrotic syndrome due to "minimal change" glomerulonephritis.


Effects of carbenicillin on blood coagulation: a study in patients with chronic renal failure. A study of coagulation has been performed on 8 chronic renal failure patients receiving carbenicillin therapy. All showed a prolongation of the bleeding, recalcification, partially-activated thromboplastin, prothrombin and thrombin times. These findings suggest the presence of an anticoagulant with an heparin-like mode of action. In vitro tests suggest that carbenicillin may be this factor. We have also shown that the drug produces a disturbance in the normal polymerization process. The implications of these findings for the treatment of (CRF) patients with carbenicillin are discussed.


Mesangial IgA glomerulonephritis in HLA-identical brothers. Two HLA identical brothers with mesangial IgA glomerulonephritis are reported. Patient 1 developed gross hematuria at age 12 and required chronic hemodialysis at age 20. Patient 2 presented at age 21 with gross hematuria and normal renal function, the follow up period is only 9 months. Neither of these patients had nerve deafness, ocular defects or complement abnormalities. The family history did not support a diagnosis of classical hereditary nephritis, but a genetic linkage is strongly suggested by the identical HLA phenotypes of these brothers (A10 - A32 - B13 - B35). The B35 antigen has previously been suspected to be linked to this disease. These observations strongly support the hypothesis of an aberrant, genetically controlled, immune response, in patients with mesangial IgA glomerulonephritis.


Celiac disease associated with immune complex glomerulonephritis. A patient with immune complex glomerulonephritis and celiac disease without dermatitis herpetiformis or other underlying disease associated with glomerulonephritis is presented. Antibodies to wheat proteins were found in serum and withdrawal of gluten from the diet resulted in disappearance of immune complexes from serum and resolution of both renal and intestinal disease, suggesting a dietary source of antigen. Despite extensive immunopathologic studies of the renal biopsy, neither dietary nor endogenous brush border antigens were demonstrated in glomeruli.


Heroin associated nephropathy: clinical and histological studies in 19 patients. Nineteen patients, 20 to 47 years old with heroin addiction and renal disease, were studied. Patients with pre-existing systemic disease that can cause renal pathology were excluded. The mean duration of the addiction was 3.8 +/- 8 years. Most of the patients had the nephrotic syndrome. Renal biopsy revealed focal histological changes in 10 patients (5 with focal sclerosis) and diffuse changes in 9. Immunofluorescence studies done in 17 patients revealed diffuse deposition of IgG and beta 1C in 11 patients and focal deposits in 6 (mostly IgM). They were followed for a period ranging from 7 to 67 months. Most patients experienced progressive deterioration of renal function except in 4 cases in whom there was cessation of the drug addiction. These 4 displayed a rise in glomerular filtration rate (from 87 +/- 16 to 100 +/- 11 ml/min), marked reduction in proteinuria (from 6.5 +/- 2.6 to 0.4 +/- 0.1 g/24 hr) and an increase in serum albumin (from 3.2 +/- 0.5 to 4.0 +/- 0.1 g/dl). In summary, the fact that the renal abnormalities of our patients could not be explained by other diseases and the marked improvement upon cessation of the addiction favors the notion that heroin addiction "per se" may be the cause of the nephropathy. However, the heroin nephropathy was not manifested by a specific histological or immunofluorescence pattern.


Comparative accuracy and complementary use of 67Ga-citrate imaging and ultrasound in the diagnosis of abdominal abscesses. Ultrasound and 67Ga-citrate imaging were used simultaneously for the evaluation of 26 suspected cases of abdominal abscess. Scintiscanning and ultrasonography identified respectively 92% and 69% of the abscesses. Jointly, both modalities detected all 13 abscesses and we suggest an integrated approach in the evaluation of such cases.


Change in shape and position of the pancreas with posture of the patient. A comparison of images obtained using 75Se-methionine revealed changes in the shape and position of the pancreas when the patient was in the supine and right lateral decubitus positions. These changes, which were appreciable and often marked in 93% of 168 patients with a probable normal pancreas, sometimes helped in the interpretation of an image. Similar changes were noted in 12 (63%) of 19 patients with chronic pancreatitis where an adequate image could be obtained.


Metastatic calcification in lungs and stomach demonstrated on bone scan in multiple myeloma. A case of multiple myeloma with associated intense radionuclide uptake in the lungs and stomach on bone scan is presented. There was no roentgenographic evidence of calcification, and the bone scan provided the only antemortem evidence of metastatic calcification.


Extrinsic lesions simulating hepatic metastases. When numerous defects are demonstrated in the liver scan of a patient confirmed as having malignant tumor, metastatic disease of the liver can usually be easily diagnosed. However, the scan must be interpreted with caution because extrinsic tumor compression often mimics metastatic disease.


32P-sodium phosphate treatment of metastatic malignant disease. Thirty-four patients with cancer of the breast and 12 with cancer of the prostate were treated with testosterone and 32P-sodium phosphate for relief of pain from bony metastases. Thirty received chemotherapy as well, and 34 received external radiation to single ports for localized pain. Of the 46 patients, 34 had good results, 6 fair, and 6 were failures. Ten patients needed transfusion for marrow depression; no other side effect was observed.


Scintigraphy of abdominal masses with 99mTc-labeled red blood cells. Scintigraphy with 99mTc-labeled red blood cells was performed in five patients for demonstration of normal anatomy and in 18 patients for evaluation of suspected or apparent space-occupying abdominal lesions. In 14 cases of abdominal lesions, the study demonstrated the extent, vascularity, and relation of the lesion to neighboring organs. We found the method was primarily useful for evaluating cases of retroperitoneal tumor and vascular malformation.


The role of 99mTc-bound phosphates and grey scale echography in the differentiation of pelvic tumors. 99mTc-pyrophosphate and 99mTc-diphosphonate have successfully been employed in the diagnosis of neoplastic pelvic disease in women. In our ongoing study, 48 women with pelvic masses, underwent dynamic pelvic scintigraphy, correlative ultrasonography and exploratory laparotomy. Dynamic scintigraphy and region of interest time/activity curves generated from computerized data acquisition have proven effective in the differential diagnosis of uterine leiomyomas from ovarian cysts. In a group of 24 women whose scintigraphic data were consistent with our criteria for uterine leiomyoma, 21 were confirmed histologically. Of 30 women, 29 were accurately diagnosed on scintigraphy as having an ovarian cyst and two patients with coexisting ovarian cysts and uterine fibroids were both correctly diagnosed prior to surgery. Detected lesions ranged from 6--22 cm in diameter. Our findings support the use of dynamic pelvic scintigraphy for differentiating uterine leiomyomas from ovarian cysts.


Outcome of adopted Vietnamese children. Beneficial effects of a normal home environment on 36 children. Thirty-six adopted Vietnamese children were evaluated physically and developmentally from four months to ten years after their adoption. All of the children had experienced early months of malnutrition, disease and deprivation. Many of the children were adopted before their first birthdays and received continuous, adequate care from invested families. Only two children had intelligence quotients less than 85 on the Slosson Test. Though physical abnormalities such as residuals of poliomyelitis, ear infections, and soft neurologic signs existed, no child was incapacitated by these conditions. From the data available in the study, developmental outcomes could not be adequately predicted on the basis of unknown genetics, early malnutrition, or early deprivation.


Adoptive families. Needs for counseling. Adoption is an on-going process which affects each member of the adoptive family during each phase of the adoptee's maturation. Specific factors, such as insecurities of the adoptive parents, the child's awareness of his adoption in relation to his age and fantasies, and recently, the introduction of the possibility that the adoptee may arrange to meet his birth-parents later in life tend to add more perplexities to problems existing in these families. The normally turbulent age of adolescence increases anxieties in these vulnerable families. The pediatrician must understand the various factors uniquely inherent in adoption so that he can more effectively provide counsel to these patients.


The prevalence of middle ear disease among learning impaired children. Does a higher prevalence indicate an association? The prevalence of middle ear disease among children who are educationally classified as learning disabled as compared to that found in normal children is discussed. A higher incidence of middle ear pathology was found among the learning impaired children. The potentially hazardous effects that middle ear disease can have upon academic and linguistic development are emphasized.


Tick-borne tularemia presenting as ulcerative lymphadenitis. In a patient with suppurative lymphadenitis who fails to respond to antibiotics routinely used for pyogenic adenitis, the diagnosis of tularemia should be considered if there is good evidence for recent tick or other insect exposure. A trial of streptomycin therapy may be indicated, pending culture and serology results, in any patient whose signs and symptoms strongly suggest this diagnosis.


A scale for assessing the severity of diseases and adverse drug reactions. Application to drug benefit and risk. Physicians were interviewed to assess their willingness to risk adverse drug reactions among patients. These untoward reactions were ranked according to severity and weighted against the primary illness being treated. A specially designed questionnaire in the form of a matrix was used. Severity was divided into seven classes denoted by progressively increasing numerical scores, W1 to W7, whose values could be calculated from analysis of the completed questionnaires. The questionnaires presented several cases, in each of which an illness of specified severity was to be treated with a drug whose untoward reactions differ in severity from that of the primary illness. Each case involved a different permutation of the severities. Analysis of the completed questionnaires yielded the mean values of the scores which were found to range from W1 = 1.00 (the mildest case) to W7 = 817 (the most serious case). It is our opinion that this type of scale is preferable to nonnumerical descriptions of severity such as "mild" or "serious," since, when combined with data on frequency of occurrence, a numerical scale permits a determination of expectation of both benefit and risk.


Kinetics and absolute bioavailability of atenolol. Twelve healthy volunteers received four single doses of atenolol (25-, 50-, and 100-mg oral solutions and a 50-mg intravenous infusion), each dose separated by at least one week. Blood and urine assayed for atenolol by a high pressure liquid chromatography (HPLC) method. Kinetic analysis of the intravenous data indicates a three-compartment model with elimination from the central compartment. The mean (+/- SD) terminal elimination half-life is 6.06 +/- 2.02 hr, the mean volume of the central compartment is 0.173 L/kg, and 94.1 +/- 8.0% of the intravenous dose is excreted in the urine. The mean value of the plasma clearance is 10.7 +/- 1.27 L/hr and of the renal plasma clearance, 10.4 +/- 1.14 L/hr. The mean absolute bioavailability for the 25-, 50-, and 100-mg oral doses is 0.52 +/- 0.18, 0.54 +/- 0.12, and 0.58 +/- 0.16, respectively. The maximum plasma concentration varies as a linear function of dose. Time to mean maximum plasma concentration (3.0 hr) and the time for half of the bioavailable dose to be absorbed (2.0 hr) do not differ significantly with dose. The mean renal plasma clearance after oral doses (9.49 +/- 1.6 L/hr) is in the same range as renal clearance after intravenous doses.


Influence of pentobarbital on effect and plasma levels of alprenolol and 4-hydroxy-alprenolol. Six healthy subjects were given placebo and a single oral 0.2-gm dose of alprenolol (Aptin) before and after 0.1 gm pentobarbital at bedtime for 10 days. The plasma concentrations of alprenolol and its metabolite 4-hydroxy-alprenolol and the inhibition of exercise tachycardia were studied for 7 hr after the alprenolol. Alprenolol and 4-hydroxy-alprenolol plasma levels were decreased by about 40% by pentobarbital but plasma half-lives were unchanged. The inhibition of exercise tachycardia during a 7-hr period was reduced from 14.0% to 10.7% by pentobarbital. The reduction was proportional to the decreased drug plasma levels. There was a significant contribution of the metabolite to alprenolol effect. The estimation of relative potency of metabolite against parent compound was 0.9 before pentobarbital and 1.9 after pentobarbital.


Renal sites of action of azosemide.

Renal sites of action of azosemide. Azosemide is a new monosulfamyl diuretic with potency and spectrum of effects similar to those of furosemide. Eight normal subjects were studied with clearance techniques during water loading and during hydropenia to assess azosemide's site of action. Solute free water reabsorption decreased from 3.1 +/- 0.3 to 0.5 +/- 0.9 ml/min after azosemide (p less than 0.05), indicating an effect of azosemide at the ascending limb of the loop of Henle. During water loading, despite significant 3.5-fold increases in fractional excretion of sodium and chloride, the per cent increase in free water formation, CH2O/CIN X 100 was not significantly changed by azosemide (10.4 +/- 1.4 control and 14.8 +/- 3.1 after azosemide). This unchanged CH2O/CIN X 100 occurred despite increased osmolal clearance after azosemide, from 2.6 +/- 0.4 to 3.8 +/- 0.4 ml/min (p less than 0.02), indicating that azosemide increased delivery of solute to the diluting segment. Evidence is discussed which implies that azosemide inhibits solute transport of the thick ascending limb of the loop of Henle, but may also affect more proximal sites.


Azosemide, a "loop" diuretic, and furosemide. Azosemide is a new monosulfamyl diuretic which inhibits solute transport throughout the thick ascending limb of the loop of Henle. This study compared equal amounts of azosemide and furosemide (20, 40, and 80 mg) in normal subjects. No differences occurred at any dose in volume, sodium, or chloride excretion when analyzed as cumulative excretion at 4, 8, or 12 hr. Azosemide 40 mg caused less potassium excretion than 40 mg of furosemide but there was no significant difference in the sodium/potassium excretion ratio. Analysis of the time course of effect showed that compared to furosemide azosemide tended to have a slower onset of effect. Differences in site of action studies between azosemide and furosemide did not manifest as differences in urinary or electrolyte excretion in our normal subjects.


Cardiovascular effects of intravenous delta-9-tetrahydrocannabinol: autonomic nervous mechanisms. The contribution of autonomic nervous system activity to the cardiovascular effects of delta-9-tetrahydrocannabinol (THC) was evaluated in 4 normal subjects. The peak heart rate rise after THC was attenuated by atropine and by propranolol, and nearly abolished by atropine-propranolol pretreatment. Blocking drugs also attenuated THC-induced changes in forearm blood flow and vascular resistance but did not affect changes in fingertip temperature. The data suggest that THC acts to induce sympathetic stimulation and parasympathetic inhibition of cardiovascular control pathways. Cardiovascular responses in an additional subject who developed hypertension after either intravenous or smoked marijuana are described.


Caffeine metabolism in the newborn.

Caffeine metabolism in the newborn. The concentrations of caffeine and metabolites in urine have been examined as a function of age to explore the remarkably slow elimination of caffeine by human infants. Urine samples were obtained from 3 adults and 10 infants aged 8 days to 8 months during therapeutic treatment with caffeine. A high-performance liquid chromatographic (HPLC) procedure involving reversed-phase partition chromatography was developed to separate caffeine and 13 of its metabolites. During the first month of life, caffeine accounted for more than 85% of the identifiable products in urine. Caffeine remained the predominant component for the first 3 months, but its percentage decreased gradually to the adult value of less than 2% by the age of 7 to 9 months. This change reflected increasing metabolite production, not decreasing urinary caffeine concentration. The adult metabolite pattern of partially demethylated xanthines and urates was attained by 7 to 9 months. The data indicate that the 4-day plasma t1/2 of caffeine characteristic of the newborn depends in large part on slow urinary excretion of unchanged drug since there is little or no metabolism. Subsequent decrease in the t1/2 to about 4 hr by the age of 8 months correlates closely with the rise in metabolite production.


Cocaine metabolism: cocaine and norcocaine hydrolysis by liver and serum esterases. The hydrolysis of cocaine and its N-demethylated product, norcocaine, by esterases was examined in liver and serum. Both liver and serum enzymatically formed ecgonine methyl ester from cocaine. The liver enzyme had a much lower affinity for cocaine than that of serum, indicating that a different form of esterase was present in liver. The liver enzyme had a similar affinity for both norcocaine and cocaine. Likewise, the serum enzyme showed similar affinities for both substrates. The Vmax estimates, however, were consistently higher for norcocaine than cocaine in both liver and serum. Benzoyl ecgonine, a major metabolite of cocaine formed by hydrolysis, was not produced enzymatically in either serum or liver; the rate of spontaneous formation at physiological pH suggests that this metabolite may arise nonenzymatically in the body.


Serum concentration and phototoxic effect of methoxsalen in patients with psoriasis. The correlation between serum concentration of methoxsalen (8-methoxypsoralen; 8-MOP) and phototoxic effect using long-wave ultraviolet light has been studied in 5 psoriatic patients. The maximum serum concentration occurred between 0.5 and 2 hr after oral administration of 0.6 mg/kg of methoxsalen. The lowest value for the minimum phototoxic dose (MPD), i.e., highest photosensitivity, was obtained between 1 and 2 hr. There was a significant negative correlation between the logarithm of the serum concentration and minimum phototoxic dose (MPD) (r = 0.780). Hence, the degree of photosensitivity appears to be related to the serum level of methoxsalen.


Chemotherapy for breast cancer.

Chemotherapy for breast cancer. Chemotherapy employed in the treatment of metastatic breast cancer effectively palliates the disease. Response rates to combination chemotherapy are high (greater than 50%); response durations, however, are still very short (less than 1 year). Future investigations must focus on the development of alternate maintenance regimens to improve response duration. Other areas for future study include the use of immunotherapy in conjunction with chemotherapy and the combination of chemotherapy and endocrine manipulation.


Randomized comparison of clinical performance of two copper-releasing IUDs, Nova-T and Copper-T-200, in Denmark, Finland and Sweden. A randomized study was conducted simultaneously in three countries to compare the clinical performance of two new IUDs, the Nova-T and Copper-T-200. Forty-four persons, midwives, general practitioners, residents and specialists in obstetrics and gynecology inserted 907 Nova-Ts and 936 Copper-Ts. The pregnancy rate of Nova-T (0.7 at one year) was significantly lower than that of Copper-T (2.2 at one year). No significant differences were observed in other termination rates. The continuation rates were 72.6 for Nova-T and 71.3 for Copper-T-200. The total experience was based on 18,035 woman months of use, with a lost to follow-up of less than 7 per cent for both IUDs.


Combined and national experience of postmenstrual IUD insertions of Nova-T and Copper-T in a randomized study. A randomized comparative study between Nova-T and Copper-T-200 was performed simultaneously in Denmark, Finland and Sweden. The results of 741 postmenstrual insertions with Nova-T and 780 with Copper-T are reported. The pregnancy rate of Nova-T was lower in every age and parity group. The pregnancy rate of Copper-T-200 varied in participating countries, whereas the pregnancy rate of Nova-T was equally low in every country. The termination rate because of expulsion with Nova-T was less affected by age and parity than that of Copper-T. Significant differences in the continuation rates with the same device were found between countries. Removals because of infection showed that women below 25 years of age had a high risk for infection regardless of parity.


Serum prolactin levels in short-term and long-term use of inert plastic and copper intrauterine devices. Serum prolactin values were assessed in 59 normally menstruating parous women; groups were divided with respect to short-term (6 weeks) and long-term (4-60 months) use of either the inert plastic IUD (Saf-T-Coil or Lippes Loop) or copper IUD (Cu-7). Preinsertion values served as controls in the short-term study while a separate control group using barrier contraception was used in the long-term study. Prospective analysis of short-term IUD use and retrospective analysis of long-term IUD use revealed no significant differences in mean hPRL compared to control values. Both short- and long-term mean values were within the normal range for serum hPRL. In addition, duration of use had no significant effect on hPRL values.


Efficacy and acceptability of intravenously administered sulprostone, a tissue-selective prostaglandin-E2 derivative, for induction of first-trimester abortion. The abortifacient effect of a new tissue-selective prostaglandin E2-derivative, sulprostone, administered intravenously, has been investigated in 166 women in the the first trimester of pregnancy. Four different dose schedules (1.7 mcg/min for 5 or 10 hour--total dose 500 mcg or 1000 mcg, 2.8 mcg/min and 4.1 mcg/min for 6 hours--total dose 1000 mcg and 1500 mcg) have been evaluated. No absolute failures occurred and no severe complications or side-effects were recorded. Best results (high abortifacient efficacy and low systemic side-effects) were obtained by infusing 1000 mcg sulprostone in appr. 10 h. Our study indicates that sulprostone appears to have a high degree of acceptability.


Rate of metabolism of norethisterone in women from different populations. The rate of metabolism of orally administered norethisterone was compared in fourteen centres by measuring plasma levels of the steroid by radioimmunoassay at varying times after oral administration of a 1 mg dose. The inter-centre differences were of the same order as the intra-centre differences. Variations in metabolism appeared not to be due to variations in body size.


Morphologic studies on IUD-induced metrorrhagia. I. Endometrial changes and clinical correlations. Morphologic studies on human hysterectomy specimens indicate the IUD elicits a vascular reaction which is most pronounced in the endometrium adjacent to the device. This reaction includes increased vascularity, congestion and increased permeability, and degeneration with defect formation. In addition, there is poor hemostatic responsiveness to vascular permeability and damage. The reaction leads to interstitial hemorrhage which undoubtedly causes metrorrhagia. A likely cause for initial vascular damage is mechanical stress transmitted by the IUD through the endometrium to its vascular network. Vascular reaction and poor hemostatic responsiveness may be perpetuated during each cycle by the products released from endothelial cell degeneration and necrosis. Bleeding is one of the most frequent complications leading to discontinuation of an otherwise effective form of long-term contraception and family spacing. Therefore, its solution could be of crucial importance to world-wide population control. Our findings suggest that better understanding of the mechanism of IUD-induced metrorrhagia should result from closer study of the endometrium adjacent to that which is compressed by the IUD.


Morphologic studies on IUD-induced metrorrhagia. II. Surface changes of the endometrium and microscopic localization of bleeding sites. Surface changes were extensively studied by light and electron microscopy in human endometrium exposed to IUD's. A wide variety of alterations in the covering epithelium and its basal lamina (basement membrane) was observed. These ranged from essentially no alteration to a covering basement membrane completely denuded of its epithelium. Erosions or discontinuities of the surface basement membrane were uncommon, and when they occurred were most often associated with extrusion of fluid and cellular elements from the stroma into the uterine lumen. Metrorrhagia associated with IUDs probably results from two basic types of hemorrhage through the endometrial surface. Tissue adjacent to the IUD with interstitial hemorrhage bleed into the uterine cavity by (1) red cell transmigration through surface membranes (surface epithelium and its basal lamina), and (2) high interstitial pressure breaks in these same membranes.


Immune reactivity of women on hormonal contraceptives: dinitrochlorobenzene sensitization test and skin reactivity to irritants. To evaluate the influence of sex steroids on immunity in 87 women on hormonal contraceptives, sensitization tests were performed with the contact allergen, 2,4-dinitrochlorobenzene (DNCB). Forty-five women were taking oral contraceptives of combined oestrogen/progestogen of the same brand (low oestrogenic and middle range progestogenic activity); 27 had received intramuscular injections of medroxyprogesterone acetate and 15 women were using a sequential pill. The results were compared with those of 44 women not taking contraceptive steroids and matched for age. In women on the combined pill and those who had received intramuscular progesterone, the mean DNCB reactivity was significantly increased (0.02 less than p less than 0.05 and 0.001 less than p less than 0.01, respectively), whereas women using a sequential pill proved to show a decreased skin reactivity in the oestrogenic phase of this pill. (p = 0.05). The changes observed proved to be specific, since no statistically significant differences in overall skin reactivity to irritants between the four groups of women could be observed. The clinical implications of these results have been considered.


A prospective study of plasma prolactin levels in women using the progesterone releasing intrauterine device (P-IUD). Plasma prolactin levels were measured by a radioimmunoassay technique in twenty-six women before and after six and twelve months of using a progesterone type intrauterine device. The results show no significant change in the prolactin levels and do not support a systemic effect of either the intrauterine device or the released progesterone.


Acceptability of a nonsurgical method to terminate very early pregnancy in comparison to vacuum aspiration. Seventy-seven patients applying for abortion during early pregnancy consented to be treated by prostaglandin vaginal suppositories or vacuum aspiration by Kahrman catheter in a random design. They also consented to participate in an acceptability study of the two procedures. Attitude and preference measures were obtained by interviewing and rating scales on three occasions: before assignment to abortion procedure, immediately after treatment, and two weeks later. The first 30 patients with complete abortion by either procedure participated in the acceptability study. Both treatments were positively evaluated but perceived to have very different characteristics. The preference for the method used for own treatment increased in both groups. Before treatment 1/3 of the patients in each group had a positive attitude to a self-administered method to induce abortion outside clinics. This proportion increased significantly after treatment but only in the group that received prostaglandin by the vaginal route.


Bioavailability and pharmacokinetics of norethisterone in women after oral doses of ethynodiol diacetate. Measurement by radioimmunoassay of plasma norethisterone (NE) has been used to compare the bioavailability of tablets containing ethynodiol diacetate (EDA) with that of a standard oral solution of this progestogen in 12 normal women. The tablets investigated were from three batches which showed different in vitro dissolution rates. There were no significant differences in the bioavailability of the tablet formulations, which were essentially bioequivalent to the solution. Peak blood levels of NE were reached within 4h of EDA administration in solution or tablets. After the peak, NE plasma levels declined in two phases, with a mean terminal elimination half lives of 4 to 6.9h. The pharmacokinetics of NE after EDA administration showed some similarity to those observed by other workers after oral doses of NE itself.


Metabolic and endocrine studies in women using norethindrone acetate implant. Subcutaneously administered implant-D containing 40 mg of Norethindrone acetate in a single silastic implant was offered to 79 subjects who desired spacing of their family. The effect of constant release of steroid from this device on metabolic and endocrine functions was studied. Each subject in the pretreatment state served as her own control. The device was removed at 8 months initially and subsequently at 5-6 months. The clinical acceptability of this method was fairly high. The results reported in this study show that Norethindrone acetate administered in this way did not cause any adverse reactions on endocrine and metabolic functions as gauged by the parameters analysed.


Antifertility effects of the steroid 5 alpha-stigmastane-3 beta, 5, 6 beta-triol 3-monobenzoate on mice. The steroid 5 alpha-stigmastane-3 beta, 5, 6 beta-triol 3-monobenzoate at a dose of 40 mg/kg of body weight has 100% interceptive activity when administered orally in a single dose during 6-7 days of gestation but it has no action on pregnancy if treated on 10th, 13th or 16th day of pregnancy. The interceptive activity of the steroid is lost by simultaneous injection of prolactin, progesterone or LH.


Copper T IUD use and ectopic pregnancy rates in the United States. Over a four-year exposure period, the rate of ectopic pregnancy for women using a Copper T IUD was less than 1 per 1000 years of use. The cumulative 4-year probability of having an ectopic pregnancy while using the Copper T was 4 per 1000 women. These results are based on a study of 35,496 women with 38,064 years of use. Data on ectopic pregnancies in the United States provide a basis with which IUD experience may be compared. The National Hospital Discharge Survey shows a doubling in the number of ectopic pregnancies and in the incidence rates between 1965 and 1976. The relative risk of ectopic pregnancy among IUD users as compared with sexually active women not using the pill or sterilization may have been above 1 in 1965. In 1976, the relative risk is estimated to have been below 1. Compared with all woman-years of exposure, including women using contraceptive sterilization and the pill, the relative risk of extopic pregnancy to IUD users in 1976 was about 1. The IUD could not have been a major factor contributing to the recent doubling in the rate of ectopic pregnancy in the U.S.


Induction of mid-term abortion by trichosanthin in laboratory animals. Trichosanthin, a protein purified from the extract of the root tuber of Trichosanthis Kirilowii, Maxim, given once only induced midterm abortion in the mice and rabbits. The effective I.P. dose for the induction of abortion in 10- or 11-day pregnant mouse was 50 micrograms. In the rabbit a dose and state of pregnancy-dependent response to Trichosanthin-induced abortion was encountered. A dose as low as 0.5 mg Trichosanthin in 22-day pregnant rabbit was adequate but 2.0 mg was needed in 17-day pregnant rabbit. Attempts to terminate pregnancy in the rat and hamster using Trichosanthin was not successful even with higher doses. When compared with prostaglandin-F2 alpha, an established abortifacient, Trichosanthin appeared to be more effective and associated with less side effects in the induction of abortion in the rabbit. Trichosanthin was ineffective to terminate early pregnancy in the 4 species studied.


Indian experience with a single long-acting vaginal suppository for the termination of pregnancies. The Indian Council of Medical Research conducted a multicentric trial with a single vaginal suppository containing 3 mg 15-Me-PGF2 alpha for terminating pregnancies. Success rate in the 290 women investigated was 79.2 per cent at 30 hours observation. The mean induction-abortion interval was 14.7 hours and the incidence of complete abortions was 58.3 per cent. Vomiting and diarrhoea were the most common side-effects noted. Vomiting was experienced by 72.3 per cent women and diarrhoea by 76.8 per cent. Although the vaginal route for administering 15-Me-PGF2 alpha is simple and the induction-abortion interval short, it is suggested that the combination of a vaginal suppository and prostaglandins intra-muscularly may lead to higher percentage of complete abortions.


Plasma levels of norethindrone and effect upon ovarian function during treatment with silastic implants containing norethindrone. The study was made to evaluate the effect upon the ovarian steroid pattern during treatment with subcutaneously implanted silastic rods containing norethindrone. Four rods, each containing 37 mg norethindrone (NET), were implanted subcutaneously in five women and left in place for 135--200 days. Plasma levels of NET, estradiol and progesterone were determined by radioimmunoassays. After an initial peak found in all subjects, the plasma level of NET declined. Great day-to-day variations of NET were found. Ovulations were suppressed during treatment in three subjects. One subject had regular ovulations throughout treatment and in one subject a single ovulation was recorded. Peaks of estradiol without subsequent ovulation were found in two subjects. The bleeding pattern was irregular; three subjects had varying degrees of spotting and bleeding, two subjects were amenorrheic. The average daily release rate was 300/micrograms, calculated from the amount of steroids lost from the removed rods. This study indicates that the release of steroid from four NET rods is high enough only initially to completely inhibit ovulation.


Renal venous thrombosis.

Renal venous thrombosis. In neonates, thrombosis beginning in small renal veins and progressing to larger veins is best termed renal venous thrombosis (RVT) since the renal vein is not usually concerned. RVT occurs dominantly in the new-born and affects males more often than females (2:1). Hyperosmolality, maternal prediabetes and angiocardiography contribute to the occurrence or RVT. Early signs and symptoms are largely non-specific with the most reliable being the presence of haematuria (49%) or a palpably enlarged and hard kidney (60%). A falling platelet count, raised FDP level of falling plasminogen level support the diagnosis in 90% of cases. Radiology and nephrosonography are very useful in establishing the presence or absence and functional state of the kidneys. Therapy consists of the maintenance of homeostasis, minimization of spread, correction of uraemia and prevention of renal hypertension from a contracted functionless kidney by elective nephrectomy after 4--6 months. Heparin therapy and peritoneal dialysis have greatly improved the outlook in bilateral cases.


Introduction of antifolics in psoriasis. A twenty-five year retrospect of antineoplastic agents in nonmalignant disease. Presented herein is a review of the beneficial use of the folic acid antagonist, aminopterin, in the treatment of psoriasis and other dermatologic disorders.


Cutaneous necrotizing venulitis.

Cutaneous necrotizing venulitis. The term vasculitis describes a variety of inflammatory changes in vessels. The most common type to affect the skin is a necrotizing venulitis associated with a neutrophilic polymorphonuclear leukocyte infiltrate. The most frequent presentation is palpable purpura on the lower extremities, but the lesions may  include urticaria and ulcers. A diagnosis of cutaneous necrotizing venulitis obliges the physician to search for the cause, associated diseases, and the extent of the vascular involvement. Antigens, either in circulating immune complexes or as haptens bound to vessel proteins, are presumed to trigger immmune responses. The differentiation of large from small vessel disease and the prediction of systemic involvement may be difficult in a specific patient. Treatment, other than removal of the antigen, is theoretic or anecdotal.


Effect of chronic combined glucocorticoid and estrogen on serum androgens and androgen binding in hirsutism. Forth-six patients with hirsutism are presented herein. Twenty-four of these patients had menstrual irregularities. Treatment with 5 mg prednisone at bedtime, and 0.625 to 1.25 mg conjugated estrogens daily except during menses resulted in a signficant decrease in serum 17 beta-ol androgens, and an even more statistically significant increase in serum androgen binding. Thus the biochemical abnormalities associated with hirsutism were improved and no apparent side effects were observed.


Puzzling posterior pigmented pruritic patches. A rarely reported dermatologic condition occurring on the scapular area and characterized by itching and pigmentation is presented herein. Several possible etiologies are considered and a mechanism explaining the possible cause is described.


Mucocutaneous lymph node syndrome in an adult receiving diphenylhydantoin. A woman who had been taking diphenylhydantoin presented with a classic picture of mucocutaneous lymph node syndrome, which has heretofore been reported exclusively in infants and children. The clinical history is presented herein.


The "don'ts" in treating psychocutaneous disease. It is not difficult for the astute clinician to diagnose a psychocutaneous illness. However, the important question that arises in the mind of a sharp clinician is whether or not to confront the patient with this information, and if consultation and psychiatric treatment is warranted before the interpretation is made. Therefore, the dermatologist treating psychocutaneous illness must treat the patient as whole and must realize that certain interpretations, although obvious, must not be made to the patient when there is a great amount of psychic overlay.


Preparing the school-age child for adoption. The development of an adoptive relationship for children who have been in the limbo of foster care is a continuous process. It is unrealistic to expect these families to live happily ever after. Agencies must begin developing regular services to meet the special needs of the families being created. To a large extent the issues that will have to be worked through relate to the stages of preparation outlined in this paper. Each stage in the child's growth may activate unresolved issues around the grief at the biological parents' rejection, confusion about identity or difficulty in working through problems. Future adoptive home recruitment must take this into account by providing training and other supports to families considering adopting the older child.


Social work stress and personal belief.

Social work stress and personal belief. In an era of accountability and the application of scientific techniques and business methods to social work, there is a danger of overlooking the magic inherent in the personal relationship.


Outward bound: a treatment modality unexplored by the social work profession. The Outward Bound Experience has a strong yet time-limited impact on delinquent youths. Social workers could help maintain the impact by establishing community-based followup programs that would reinforce and sustain the positive attitudes and behaviors developed.


Studies in heterochromatin DNA: accessibility of late replicating heterochromatin DNA in chromatin to micrococcal nuclease digestion. Heterochromatin DNA in cactus mouse (Peromyscus eremicus) replicates in the late S phase of cell cycle. A method of obtaining cells which contain DNA preferentially labeled at heterochromatic areas by a pulse-labeling of late replicating DNA is described. When the nuclei of P. eremicus cells containing radioactively labeled DNA in heterochromatin were digested with micrococcal nuclease and the resultant nucleosomal DNA was separated by gel electrophoresis, it was found that the repeat length of nucleosomal DNA in the heterochromatin DNA is not different from that of the bulk of the genomic DNA. Furthermore, there was no significant difference in the accessibility to digestion by micrococcal nuclease between the late replicating heterochromatin DNA and the total DNA under our digestion conditions. Two dimensional gel electrophoresis patterns of nucleosomal DNAs isolated from micrococcal nuclease digested nuclei from P. eremicus, P. collatus, and P. crinitus cells in culture were very similar. Cytogenetic data showed that these three species are different in heterochromatin but similar in euchromatin.


The relation of radiation sensitivity to pronuclear chromosome structure. II. Differences in radiation sensitivty between two stocks of Phryne cincta characterized by low or high crossing-over frequency. After treatment of spermatozoa of Phryne cincta from a Berlin population (bs) with low crossing-over and from an Alpine population (as) with high crossing-over frequency, egg mortality was ascertained and chromosomal mutation rate determined by examination of the polytene chromosomes of the F1 progeny. - The as stock exhibits a 1.33 times greater radiation sensitivity than the bs stock, both in chromosomal mutation and in egg mortality rates. There is no evidence that factors other than structural ones account for the differences in radiation sensitivity. From inversion length measurements, it was proposed that a reduction of the spiral diameter of the paternal pronucleus chromosomes is responsible for a higher site number and thereby for a greater radiation sensitivity.


Transcription and hybridization of 125I-cRNA from flow sorted chromosomes. Metaphase chromosomes from the Chinese hamster cell line M3-1 were separated by means of a flow sorter. Two chromosome fractions were used for this study: A, which consisted of 95% pure chromosome no. 1, and B, which was 90% pure chromosome no. 2. The DNA of 10(6) chromosomes of each type was purified, and a 125I-cRNA transcript was synthesized in a reaction containing E. coli RNA polymerase and carrier-free 125I-CTP (1.7 Ci/mumole). The cRNA product synthesized with template DNA from 10(5) sorted chromosomes contained more than 10(6) dpm. The electrophoretic mobility profiles of the cRNAs on 7.5% SDS acrylamide gels demonstrated that more than 50% of the ribo-polymers were equal to or longer than marker E. coli met-tRNAf. In hybridization reactions 21% and 17% of the transcripts from Chinese hamster whole cell and sorted chromosome DNA hybridized to Chinese hamster DNA and did not hybridize significantly over background in reactions containing calf DNA at Crt values of 1.3 and 1.9 x 10(2) mole sec/l. Labelled cRNAs transcribed from the DNA of sorted chromosomes hybridized with the DNA of each sorted chromosome fractions at a Crt of 0.6 mole sec/l. This study demonstrated that the DNA can be (1) recovered from small numbers of highly purified flow sorted chromosomes, (2) used as template by E. coli RNA polymerase and (3) used to prepare a cRNA in reactions containing polymerase and carrier-free 125I-CTP to yield a product which can be employed for hybridization analysis.


Length heterogeneity of amplified circular rDNA molecules in oocytes of the house cricket Acheta domesticus (Orthoptera: Gryllidae). Amplification of the genes coding for rRNA occurs in the oocytes of a wide variety of organisms. The amplification process appears to be mediated through a rolling-circle mechanism. The approximate molecular weight of the smallest rDNA circles is equivalent to the estimated combined molecular weight of DNA which codes for a single ribosomal RNA precursor molecule and an associated non-transcribed spacer DNA sequence. RNA-DNA hybridization studies carried out on oocytes of the house cricket, Acheta domesticus, suggest that DNA coding for rRNA accounts for only a small fraction of the rDNA satellite, all of which is amplified in the oocyte. In order to test the possibility that the remainder of the amplified rDNA represents spacer and to determine whether a rolling-circle mechanism might also be involved in amplification in A. domesticus oocytes, rDNA was isolated from ovaries of A. domesticus and spread for electron microscopy. A large proportion of the rDNA isolated from ovaries is circular, while main-band DNA and rDNA prepared from other tissues demonstrates few if any circles. The mean size of the smallest rDNA circles is approximately 8 times longer than the length estimated for DNA which codes for 18S and 28 S rRNA. Denaturation mapping shows the rDNA circles to contain two major readily denaturing regions located about equidistant from one another on the circle. Each readily denaturing region accounts for 4--6% of the total DNA in the circle. The fact that only 12% of the average molecule is required to code for A. domesticus 18S and 28S rRNA is consistent with the hybridization data. Considerable size heterogeneity exists in the length of the smallest class of rDNA molecules. In the rDNA of other species such heterogeneity has been shown to reside in the non-transcribed spacer.


In situ hybridization of highly repetitive DNA to chromosomes of Triturus cristatus. Highly repetitive DNA of C0t 0--0.2 was purified from whole DNA of Triturus cristatus carnifex, labelled by nick translation, and in situ hybridized to RNA transcripts on the loops of lampbrush chromosomes and to the DNA of mitotic chromosomes from intestinal epithelium from the same species. The labelled DNA bound to 20--30 loops on the long arms of lampbrush bivalent 1, a pair of loops near the centromere on bivalent 10, and a number of other loops most of which were localized in pericentric regions. In mitotic preparations the same labelled DNA bound to the heteromorphic regions of the long arms of both chromosomes 1, and to the centromeric regions of all chromosomes. Centromeric labelling was light on chromosomes 4 and particularly clear on the 3 shortest chromosomes of the set. The heavy labelling of the heteromorphic arms of chromosome 1 is discussed in relation to several other peculiar properties of these arms, including their extraordinary lengths, their Giemsa banding patterns, and the absence of meiotic crossing over. It is suggested that insofar as the results with DNA/DNA hybridization and mitotic chromosomes match those obtained with the DNA/RNA-transcript hybridization and lampbrush chromosomes, confidence in the latter technique may be increased accordingly.


Behaviour of sex chromosome associated satellite DNAs in somatic and germ cells in snakes. Sex chromosome associated satellite DNAs is isolated from the snakes Elaphe radiata (sat III) (Singh et al., 1976) and Bungarus fasciatus (Elapidae) (minor satellite) are evolutionarily conserved throughout the suborder Ophidia. An autosome limited satellite DNA (B. fasciatus major satellite) is not similarly conserved. Both types of satellites have been studied by in situ hybridisation in various somatic tissues and germ cells where it has been observed that the W sex chromosome remains condensed in interphase nuclei. In growing oocytes however, the W chromosome satellite rich heterochromatin decondenses completely whilst the autosomal satellite rich regions remain condensed. Later, the cycle is reversed and the W chromosome condenses whilst the autosomal satellite regions decondense. In a primitive snake (Eryx johni johni) where the sex chromosomes are not differentiated and where there is no satellite DNA specific to them, these phenomena are absent. - The differential behaviour of autosomal and sex chromosome associated satellite DNAs is discussed in the light of gene regulation.


Marked increase in ribosomal RNA gene multiplicity in a rat hepatoma cell line. An H4-IIE-C3 hepatoma cell line derived from an ACI rat has been shown to have differentially stained regions attached to the short arms of chromosomes 3, 11 and 13 and the long arm of an unidentified small chromosome. There is cell to cell variability in the number and size of the differentially stained regions, which contain, on the average, about 5% of the total DNA. A series of secondary constrictions occur at intervals along the length of each differentially stained region. These stain with silver by the Ag-AS method, indicating that the differentially stained regions contain sites of active 45S ribosomal precursor RNA transcription. In situ hybridization to metaphase chromosomes shows that the hepatoma cells have a 10 fold increase in DNA coding for 18S and 28S ribosomal RNA, 90% of it located in the differentially stained regions, and no change in the number of genes coding for 5S RNA. These results have been confirmed by filter disc hybridization.