Occupational lead exposure and renin release

Hypertension may result from chronic lead exposure. Lead poisoning arising from "moonshine whiskey" drinking has been associated with a rise in plasma renin activity. In the present study, plasma renin concentration following intravenous administration of frusemide was measured in eleven subjects with moderate or severe lead poisoning of industrial origin. The results were compared with those obtained for seven normal, control subjects. There was no significant difference in response obtained in the two groups. Industrial lead poisoning does not appear to affect renin release. The combined insult of lead and alcohol may explain the findings in the previous study.     

Effects of delta-aminolaevulinic acid administration on social behaviour in the laboratory mouse

Platelets were examined to enable a simultaneous investigation to be made of indolylamine and electrolyte metabolism in affective disorder.No significant differences were detected in either platelet membrane ATPase or adenyl cyclase specific activity in any of the groups of patients studied, when compared with appropriate controls. A reduced V _max and for the 5-hydroxy-tryptamine uptake process into platelets was observed in both unipolar and bipolar depressed groups. The K _m for this process was not significantly different in any of the patients from that found in control subjects.Lithium therapy was shown not to influence significantly any of the platelet parameters examined.It is suggested that membrane enzyme changes found in some peripheral cells in patients suffering from affective disorder, i.e. reduced Na⁺+K⁺-ATPase activity in erythrocytes in depression, is not common to all peripheral cells and may or may not reflect central nervous system changes.     

Increase in mouse brain dopamine content by baclofen: Effects of apomorphine and neuroleptics

Baclofen, like -butyrolactone, causes a dose-dependent increase in the concentration of dopamine in the mouse brain without affecting the content of norepinephrine. This increase is antagonized by apomorphine. Haloperidol but not pimozide counteracts this effect of apomorphine and dose-dependently enhances the increase in brain dopamine produced by baclofen. The results suggest that baclofen reduces impulse flow in dopaminergic neurons in a manner similar to that produced by -butyrolactone.     

Differential drug effects on dopamine concentrations and rates of turnover in the median eminence,olfactory tubercle and corpus striatum

Summary Dopamine synthesis rates were determined in terminals of tubero-infundibular, mesolimbic and nigrostriatal neuronal systems by observing the decline of dopamine contents in the median eminence, olfactory tubercle and corpus striatum after administration of-methyltyrosine. In control (no drug treatment) animals the rate of synthesis of dopamine was greater in the median eminence than in the other two brain regions. Haloperidol increased and piribedil decreased dopamine turnover in the corpus striatum and olfactory tubercle, but not in the median eminence.-Butyrolactone increased dopamine concentrations in the olfactory tubercle and striatum without altering the concentration in the median eminence. Thus, the regulatory mechanisms governing the activity of central dopaminergic neurons in the tuberoinfundibular system appear to differ from those in the mesolimbic and nigrostriatal systems.Supported by USPHS grants NS09174 and MH13174.G. A. Gudelsky is a predoctoral student supported by USPHS Training Grant GM1761.     

Differential actions of dopamine agonists and antagonists on the γ-butyrolactone-induced increase in mouse brain dopamine

-Butyrolactone (GBL) increased the dopamine concentration in the forebrain of the mouse. Apomorphine dose-dependently antagonized the GBL effect, while piribedil was less effective. Haloperidol prevented the antagonism of GBL by apomorphine but pimozide was ineffective in blocking apomorphine. After chronic treatment with haloperidol or pimozide, there was no alteration of the maximum GBL-induced increase in dopamine nor was there any significant change in the antagonism by apomorphine, although a trend toward increased sensitivity to apomorphine was noted in the group withdrawn from haloperidol. These results suggest that in the mouse, haloperidol is a more effective antagonist of presynaptic dopamine autoreceptors than pimozide, while apomorphine is a better presynaptic agonist than piribedil.     

MRI of the intraorbital optic nerve in patients with autosomal dominant optic atrophy

Measurements of the intraorbital optic nerve were made using high-resolution coronal MRI in 10 adults with autosomal dominant optic atrophy. Comparisons were made with previous studies of 10 normal adult subjects. The cross-sectional diameters of the optic nerve and the perineural subarachnoid space were measured and a ratio of there diameters at anterior, mid and posterior positions along the optic nerve was determined. We found a statistically significant difference in the mean optic nerve: sheath ratio between the control group and patients with autosomal dominant optic atrophy. At anterior, mid and posterior locations along the optic nerve it is significantly smaller in patients with optic atrophy. We have demonstrated that the loss of ganglion cells, previously documented in dominant optic atrophy, is associated with a significant loss of optic nerve tissue and thinning of the nerve along its length. Received: 6 July 1999/Accepted: 22 July 1999     

Inhalational versus intravenous induction. A survey of emergency anaesthetic practice in the United Kingdom

A survey was constructed to ascertain the views of The Royal College of Anaesthetists tutors regarding the acceptability of inhalational induction with sevoflurane for emergency anaesthesia. A questionnaire was sent to all tutors asking them to indicate their preferred choice of anaesthetic technique, and whether they believed inhalation induction with sevoflurane to be acceptable, in each of four scenarios: acute epiglottis; bleeding after tonsillectomy; appendicitis; and laparotomy in the shocked patient. Two hundred and sixty-two (89%) completed questionnaires were received from 294 college tutors. We have shown that the majority of The Royal College of Anaesthetists tutors would use sevoflurane for patients with an acutely compromised airway. One in four college tutors would accept the use of sevoflurane for a shocked patient for laparotomy. Anaesthetists who manage critically ill patients with an inhalational induction should be reassured by the fact, that a significant proportion of their colleagues would find this technique acceptable.     

Recognition of Crohn Disease on Incidental Gastric Biopsy in Childhood

The role of gastric biopsy in the diagnosis of Crohn disease (CD) in the pediatric population has not been well described. We assessed the use of gastric biopsies in the diagnosis of CD using specific histopathologic parameters: granulomata, focal gland injury with neutrophils (glandulitis or glandular abscesses), and/or focal concomitant eosinophilic infiltrates. Multiple (438) consecutive pediatric biopsies with inflammation spanning a 5-year period were identified from archival material in patients ages 2 months to 16 years. A total of 56 CD cases were confirmed using colon biopsies and clinical and radiologic data as the gold standards of diagnosis. Review of hematoxylin and eosin (H&E) slides and Diff-Quik stained slides (negative for Helicobacter pylori) isolated 53 cases which suggested CD on gastric biopsy: 20 cases with granulomata, 14 cases with focal glandulitis and glandular abscesses, and 19 cases of focal glandulitis/glandular abscesses with eosinophilic infiltrates. Seventy-seven percent (43/56) were correctly identified as patients with CD. Twenty-three percent (13/56) of CD cases were not identified primarily because of concurrent H. pylori infection identified on Diff-Quik stain with a superimposed nonspecific diffuse gastritis. The use of Diff-Quik stain to identify H. pylori cases after all other factors are considered was significant (P = 0.0145); a negative stain, combined with the identified histopathologic features indicative of CD, significantly increased the accuracy of CD diagnosis. CD was mimicked by other gastric granulomatous diseases (actinomyces, 1 case; chronic granulomatous disease of childhood, 1 case). Gastric biopsy can be used to identify or support the diagnosis of CD in children in the appropriate clinicopathologic setting.     

Classic Adamantinoma with Osteofibrous Dysplasia-like Foci and Secondary Aneurysmal Bone Cyst

Adamantinoma, a rare bone lesion of the tibia and fibula, has two distinct variants, classic adamantinoma and osteofibrous dysplasia-like adamantinoma. Composite lesions have not been described. Aneurysmal bone cyst is a benign cystic lesion which may also occur in the tibia and fibula. We report an unusual case of classic adamantinoma with osteofibrous dysplasia-like areas and foci of secondary aneurysmal bone cyst with prominent giant cells. A lesion was diagnosed in a 17-year-old girl with a 14-year history of a slowly enlarging left tibial mass and increasing deformity. Pathologically, the predominant pattern was classic adamantinoma, with minor foci of osteofibrous dysplasia-like adamantinoma and areas of secondary aneurysmal bone cyst with abundant multinucleated giant cells. We report the clinical, radiologic, and pathologic features of this case, and summarize lesions associated with secondary aneurysmal bone cyst. To our knowledge, the association of adamantinoma with secondary aneurysmal bone cyst has not been previously reported.