Is CT ventriculomegaly related to hypercortisolemia?
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to M Boucher.
Explore the source record for details and available documents.
Reversal of normal cerebral asymmetry has been reported to be more frequent in children with higher cortical dysfunction and in schizophrenics, in whom it has clinical significance as well. As there are few studies of bipolar patients, we attempted to determine if significant reversal would be found in a clearly diagnosed sample of bipolar patients. As technical differences may account for varying results, we used two previously reported methods and a modified technique. Correlations of computed tomography (CT) findings with neuropsychological variables (Halstead Reitan Battery and WAIS subtests) were also studied. Bipolars and controls did not differ on any CT measure, nor were there meaningful correlations between asymmetry and neuropsychological variables. If if is confirmed that schizophrenics have increased reversed cerebral asymmetry but bipolars do not, it may point to an important difference, as all other CT abnormalities initially described in schizophrenics are now also noted in bipolar patients.
The effects of procainamide and its metabolite N-acetylprocainamide (NAPA) on atrial effective refractory period (AERP), atrial rate, ventricular rate, and mean blood pressure were investigated in conscious dogs with chronic atrioventricular block and implanted atrial pacing electrodes. Procainamide at cumulative doses of 4.3, 13.0, and 30.3 mg/kg and NAPA at equimolar doses of 5.1, 15.3, and 35.7 mg/kg (i.e., at plasma levels covering the assumed therapeutic range) concentration-relatedly lengthened AERP, as reflected by the decrease of maximal atrial frequency determined by pacing. Procainamide was 1.2-1.5 times more potent than NAPA in this regard. Both drugs increased atrial rate in relation to their plasma concentrations--procainamide 1.2 times more than NAPA. Procainamide decreased ventricular rate at the two highest doses, while NAPA decreased it only at the highest dose after having increased it at the lowest. Procainamide lowered mean blood pressure at the lowest dose and increased it 15 min after the highest, whereas NAPA produced an increase in mean blood pressure for each dose. Taken together, these results on atrial rate, ventricular rate, and mean blood pressure indicate that the two drugs possess distinct pharmacological properties--i.e., procainamide exhibits slightly more marked direct vagolytic and depressor effects than does NAPA and exerts quite different blood pressure effects from those of NAPA. Thus, these data suggest that NAPA, especially when present at high levels, may markedly affect expected responses in patients being treated with procainamide.
Embryonic mouse brain cells from the basal forebrain region were labeled in cell suspensions and transplanted into the denervated hippocampal formation of adult rats. Many labeled cells had the appearance of typical pyramidal neurons with dendrites that had both growth cones and neurites. Labeled neurons and glia were seen at several sites in the hippocampal formation. The neurons were located predominantly along the dentate granule cell layer and the pyramidal neurons had a preferred orientation of their apical dendrites toward the molecular layer. Since it was rare to see a surviving labeled neuron within the injection site, migration away from the injection site seemed important for survival of the cells. The methods used in these experiments should become an important adjunct to the methods for studying the migration, differentiation and growth of neurons and glia.
Chronotropic effects of histamine and dimaprit were studied in the conscious dog with chronic atrioventricular block. Histamine at 0.2-5 micrograms/kg and dimaprit at equimolar doses (i.e. 0.25-6.25 micrograms/kg) increased atrial rate dose-relatedly. Blockade of muscarinic receptors reduced these effects and simultaneous blockade of muscarinic and beta-adrenergic receptors abolished them. Histamine and dimaprit moderately increased ventricular rate. Blockade of muscarinic receptors did not modify these effects, but blockade of beta-adrenoceptors with or without simultaneous blockade of muscarinic receptors suppressed them. After blockade of beta-adrenoceptors, histamine and more rarely dimaprit sometimes decreased atrial and ventricular rates. These effects were prevented by additional muscarinic blockade. Histamine and dimaprit lowered mean blood pressure to the same degree before and after each antagonist. The positive chronotropic effects of histamine and dimaprit, at these doses, are probably reflex responses to their hypotensive effects. The negative chronotropic effects of histamine after pindolol are due to muscarinic receptor activation. No evidence was found to implicate histamine-specific receptors in any of the chronotropic effects of histamine and dimaprit.
The nonstress test remains the most widely used method of antepartum fetal health assessment in multiple gestations. However, few data are available on factors influencing its results in those cases. Our observation on 530 such tests has shown results similar to those in singleton gestations. Prematurity was associated with a higher rate of nonreactive tests; however, order and mode of presentation had no impact.
Atrial and ventricular chronotropic effects of the individual stereoisomers of propranolol, pindolol, metoprolol and penbutolol were studied in conscious dogs with chronic atrio-ventricular (A-V) block. Ventricular beta-adrenoceptor blocking activity was assessed for all drugs against isoprenaline under the same experimental conditions. At low doses, the stereoisomers of propranolol and penbutolol decreased atrial rate, whereas those of pindolol and metoprolol produced an increase. At higher doses, all drugs increased atrial rate. All drugs decreased ventricular rate dose-dependently except (+)-pindolol. Relative ventricular beta-blocking potencies of the (-)-isomers of propranolol, pindolol, metoprolol and penbutolol were respectively 38, 21, greater than 43 and 31 times higher than those of their corresponding (+)-isomers. In addition, beta-blocking potencies of (-)- and (+)-pindolol were respectively 60 and 120 times higher, those of (-)- and (+)-penbutolol 7 and 8 times higher and those of (-)- and (+)-metoprolol 4 and greater than 4 times weaker than those of (-)- and (+)-propranolol. At comparable levels of ventricular beta-adrenoceptor blockade, (-)-pindolol and (-)-metoprolol were more potent in producing ventricular bradycardia than their respective (+)-isomers, whereas (-)- and (+)-propranolol and (-)- and (+)-penbutolol were equiactive. In addition, regardless of which isomer was being studied, the order of ventricular bradycardiac potencies, at comparable levels of beta-adrenoceptor blockade, was metoprolol greater than propranolol greater than penbutolol greater than pindolol. In addition, regardless of which isomer was being studied, the order of ventricular bradycardiac potencies, at comparable levels of beta-adrenoceptor blockade, was metoprolol > propranolol > penbutolol >pindolol. 5 These results show that antagonism of beta-adrenoceptors in the ventricle is at least partly responsible for the ventricular bradycardiac effect produced by these drugs, but also that some other factor, apparently distinct from the membrane stabilizing activity, is involved, suggesting the existence of some other as yet unknown pharmacological property of the beta-adrenoceptor blocking drugs, especially evident in metoprolol. Finally, these results demonstrate that the intrinsic sympathomimetic activity exhibited by some of these drugs attenuate their bradycardiac effect.
Based on recent computed tomography (CT) studies that have suggested the presence of distinct structural abnormalities in the brains of chronic schizophrenics, the authors evaluated 23 chronic schizophrenics and 23 controls by CT, using linear and area lateral ventricular measures, sulcal and Sylvian fissure widths and cerebral density measures. Technical problems inherent in CT studies and their impact on the use of data generated by such studies are discussed. Although there were few differences between groups, there emerged a distinct subgroup of schizophrenic patients with mild lateral ventricle enlargement associated with increased cortical density. The possible etiopathology for this atypical combination is discussed, including the striking parallels with a recent neuropathological study's findings.
There are numerous reports of lateral cerebral ventricle enlargement on computed tomography (CT) in schizophrenics, but the significance and its relationship to traditional notions of organicity remain unclear. Therefore we studied a subgroup of chronic schizophrenics who had lateral ventriculomegaly (and also cortical hyperdensity) on a battery of relevant biological, neuro-psychological, and clinical parameters such as electroencephalogram (EEG), platelet monoamine oxidase (MAO) and serum dopamine-beta-hydroxylase (DBH) activity, the Halstead Reitan Neuropsychological Battery (HRB), premorbid personality adjustment, drug response, positive and negative symptoms, employment history, and family history. Our findings support the notion that there is an "organic" subgroup of schizophrenia that has 1) CT structural abnormalities such as lateral ventricle enlargement and cortical hyperdensity; and cerebral dysfunction or deficits as evidenced by 2) an increased incidence of abnormal EEGs and also 3) greater impairment on neuropsychological tests. The biochemical measures, platelet MAO and serum DBH activity, nor any of the clinical measures could differentiate between the subgroups. The implications of these findings for the subtyping of schizophrenia are discussed.
Explore the source record for details and available documents.
During a one-year period, 29 patients at 37 weeks' gestation or later were referred to the breech version clinic at Los Angeles County/University of Southern California Medical Center and found to have sonographic evidence of a transverse lie. Because of the relative instability of the lie and the high probability of spontaneous conversion, the patients were not considered candidates for version and were returned to their referral agencies for subsequent prenatal care. The subsequent outcomes in these patients were reviewed. Twenty-four (83%) spontaneously converted to a longitudinal lie and presented in labor with either a vertex (15 [52%]) or breech (9 [31%]) presentation. The five (17%) remaining patients presented in labor with a persistent transverse lie. Overall, the cesarean section rate was 13 of 29, or 45%. The indications for cesarean section were breech presentation, eight (62%), and transverse lie, five (38%). Major complications included two prolapsed cords, one spontaneous uterine rupture and one neonatal death. Based on a review of our experience, it appears reasonable to consider external version in any patient with a persistent transverse lie around 39 weeks. The high rate of subsequent cesarean section and major morbidity associated with expectant management of these patients suggests that if version is unsuccessful, strong consideration should be given to elective cesarean section.
The effects of spontaneous and atropine-induced variations of vagal tone on atrial refractoriness were studied in the conscious dog with complete atrioventricular block. Atrial rate and vagal tone, assessed with atropine, along with maximal paced atrial frequency were monitored for 90 days after the creation of atrioventricular block. The effects of atropine on maximal paced atrial frequency were also studied over the same period. Atrial rate was initially high and then fell back to values close to preoperative sinus levels. Vagal tone was first low and then rose back to values close to preoperative ones. The time-courses of atrial rate and vagal tone were correlated. The rise in vagal tone was accompanied by a correlated increase in maximal paced atrial frequency and thus a shortening of the atrial effective refractory period. However, atropine never significantly lengthened the atrial effective refractory period. This work clearly demonstrates the consistent shortening effect of vagal tone on the atrial effective refractory period in the conscious dog as well as the still unexplained inability of atropine to offset this effect, which may arise from a two-fold action of atropine on the heart.
Listeria monocytogenes is an underdiagnosed and underreported cause of congenital sepsis. Twenty mother/infant pairs from whom Listeria was isolated were studied at the University of Southern California School of Medicine and Women's Hospital during the last ten years to delineate antepartum factors indicative of a fetus at high risk for perinatal Listeria sepsis. The combination of high maternal leukocyte count, fetal tachycardia, decreased fetal heart rate variability, and, especially, the absence of intrapartum fetal heart rate accelerations was associated with a complicated course for the neonate with congenital Listeria sepsis. Intrapartum administration of antibiotics decreased fetal morbidity and mortality but did not impair recovery of the organism.
Eight cases of [absence status] are reported, occurring in old patients (7 females, 1 male), mean age 75 years, without any known history of epilepsy. The main clinical feature was a fluctuating state of consciousness, during which the EEG showed diffuse spikes and polyspikes with a frontal predominance. These abnormalities disappeared after intravenous benzodiazepine administration, resulting in most cases in a spectacular clinical improvement. Five of our patients had a depressive history and were taking antidepressive or psychotropic drugs. Hyponatremia or hypokalemia probably secondary to diuretic medications, was present in 4 cases. No recurrence occurred with or without long-term anti-epileptic medication.
Explore the source record for details and available documents.
This paper reviews methods for producing experimental complete atrioventricular (A-V) block in dogs, with emphasis on those methods that enable chronic A-V block to be obtained. The dog with chronic complete A-V block, particularly when unanesthetized, is a useful experimental model, and the production of complete A-V block is an approach to the clinical treatment of certain supraventricular arrhythmias. Criteria for the choice of method are discussed, and the results obtained to date in the unanesthetized dog with chronic A-V block are briefly described to illustrate the usefulness of this experimental model.
One consequence of the development of the use of ultrasound in obstetrics is the multiplication of parameters studied by the ultrasonographer. This has prompted the development of expensive computerized systems to assist the person doing the examination in evaluating his results. A program designed to be used with a relatively inexpensive, hand-held calculator is described. It gives the gestational age corresponding to the most commonly measured dimensions, the estimation of fetal weight of the examined fetus, and numerous other parameters used in clinical interpretation of ultrasound examinations.