Biomedical subjects
Publications and source records attributed to N Martin.
Cholesterol granulomas arise scarcely within the middle ear cavities revealed by a conductive deafness. They appear on the CT scan as a non specific mass developed in the middle ear cavities with bone defects. MRI allow the diagnosis as cholesterol granulomas is defined by hyperintensity on all sequences.
The authors describe seven cases of pituitary adenoma with acute neurological symptoms (the so-called pituitary apoplexy), which were examined by magnetic resonance imaging (MRI). Four patients underwent surgery and the diagnosis of pituitary adenoma was histologically confirmed. In 3 patients, conservative treatment was decided and serial MRI examinations showed progressive decrease in size of the tumour, leading in one case to an empty sella. Computerized tomography (CT) was positive in all 7 cases, but less contributive than T1-weighted MRI images both for tumoral volume determination and detection of intratumoral haemorrhage. Although theoretical problems may arise concerning the diagnosis of acute intratumoral bleeding at an early stage, the authors emphasize the value of MRI in showing the extension of the tumor into the retroclival cistern and the cavernous sinus, especially when surgery is not performed in the acute period.
This report presents the clinical histories and the radiological, histologic and bacteriological findings of nine patients with tuberculosis of the knee, diagnosed and treated between 1974 and 1980. The authors review the results of the medical and surgical treatments.
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Modifications in beta-endorphin levels in cerebrospinal fluid have been described following lumbar puncture and metrizamide injection. Cerebrospinal fluid (CSF) samples were obtained from 19 patients before and after lumbar myelography. Two radioimmunoassays were used. One was a commercial kit; and the other one (developed in our laboratory) used a chromatographic removal from beta-lipotrophin. No definite variation of beta-endorphin was observed after myelography, using either the commercial kit or a more sophisticated procedure. Some controls were prepared by adding metrizamide or Iopamidol in vitro to CSF samples in order to evaluate a non specific effect of these contrast media. The results obtained with these controls suggest that the discrepancy of results may be explained simply by assay artifacts due to drug interferences when using the commercial methods.
Of 222 patients suspected of having pulmonary tuberculosis (PT), studied during a one-year period, we performed fiberoptic bronchoscopy together with bronchoalveolar lavage (BAL), bronchial washing and postbronchoscopy sputum smears and Löwenstein cultures in 20 patients. Bronchoalveolar lavage proved to be the most effective method leading to diagnosis in 17 of 20 cases. Diagnosis was obtained in 11 of 20 cases using bronchial washing and postbronchoscopy sputum. The results of this study suggest that bronchoscopy may be required in selected cases for the diagnosis of PT. However, it should be accompanied by BAL, bronchial washings and postbronchoscopy sputum smears. Indications for bronchoscopy as a diagnostic tool for PT may include: (a) patients suspected of having PT with negative smears and in whom treatment must be started due to clinical status; (b) suspicion of associated neoplasia; (c) selected patients with negative Löwenstein cultures; (d) lack of material being obtained by simpler methods.
The biological basis for autoimmunity and immunoincompetence in the BB rat has yet to be localized. In spite of normal thymic histology, thymocyte subsets and blastogenesis, thymus gland products (thymosins) have yet to be studied. In the present report, thymus gland function was studied by measuring thymosin alpha 1 levels at one time point in the BB rat compared with control rates, and BB rat responses to exogenous thymosin (Thymosin fraction 5) were observed. At five months of age, BB rats had thymosin alpha 1 levels comparable to Lewis and Wistar furth rats. Thymosin fraction 5 increased the ratio of peripheral blood W3/25 positive to OX8 positive cells, but otherwise had no effect on the BB rats' T-cell immunodeficiency, or frequencies of tissue autoantibodies or insulin-dependent diabetes. Although B-lymphocyte counts were normal in BB rats, splenocyte responses to B-lymphocyte mitogens were depressed. However, thymosin fraction 5 improved the BB rat B-lymphocyte blastogenesis to near normal for Mycoplasma neurolyticum. Coupled with our previous work, our results suggest that the immune derangement in the BB rat resides outside the thymus.
Human polymorphonuclear neutrophils (PMN), when exposed to soluble or particulate stimuli, can destroy various types of cells. The purpose of the present work was to investigate the toxicity of phorbol myristate acetate (PMA)-stimulated PMN against hepatocytes. Neutrophils were incubated in basal conditions or after stimulation by 100 ng/ml PMA in the presence of rat hepatocytes isolated by collagenase digestion. Cytotoxicity was quantified by the percentage of alanine aminotransferase (ALAT) activity released by hepatocytes in the culture medium. Whereas unstimulated PMN had only minor effects, PMA-stimulated PMN induced, after a 16-hour incubation, a 29.5% ALAT activity release at a PMN/hepatocyte ratio of 20/1. At the same ratio, stimulated PMN induced a 1.5% and a 16.6% ALAT activity release at 1 and 4 hours, respectively. At 1 hour, electron microscopy showed intimate contacts between PMN and hepatocytes; hepatocytes appeared morphologically normal. Hepatocytic lesions were moderate at 4 hours and marked at 16 hours. Neutrophil-induced hepatocyte toxicity could not be explained by the production of reactive oxygen intermediates since: (a) hepatocyte toxicity was not prevented by either superoxide dismutase or by catalase; (b) PMN obtained from a subject with chronic granulomatous disease were as toxic as PMN obtained from a normal subject. By contrast, a proteinase-mediated mechanism could be implicated since: (a) the supernatant of stimulated PMN induced a 45.9% ALAT activity release, after 16 hours of incubation; (b) three neutral proteinase inhibitors (i.e., alpha 1-proteinase inhibitor, phenylmethylsulfonylfluoride, soybean trypsin inhibitor) as well as fetal calf serum decreased this toxic effect by 82, 86, 81 and 70%, respectively. These inhibitors had no or minor protective effect on the toxicity of stimulated PMN coincubated with hepatocytes. This could be explained by the existence of intimate contacts between PMN and hepatocytes impeding the action of antiproteinases. Our results suggest that PMA-stimulated PMN can damage hepatocytes through the release of proteinases and that the existence of close contacts between PMN and hepatocytes might play a major role in this toxic effect.
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Intradural disk herniation is a rare condition. Most of reported cases involve the lumbar spine and have histories of chronic low back pain followed by an acute episode of radicular pain with neurologic deficit. The authors report the myelographic and lopamidol-CT findings in a case of a L4-5 intradural disk herniation. These two examinations demonstrated an intradural multilobular mass associated with an extradural component at the level of the disk space and with a same density as it. Anatomic adherences between dura-mater and posterior longitudinal ligament could explain the primary mechanism of these intradural disk herniations; but operative or traumatic antecedents are often noted. Most often operation discloses only the intradural component with a small anterior dural cleft, without extradural abnormalities. Postoperative follow up is usually good.
Two cases of Eale's disease, with neurological involvement have been studied with magnetic resonance imaging (MRI). In the first case the ophthalmological disease had been diagnosed ten years before the onset of a cerebellar ataxia. In the second case the characteristic ocular changes were followed eight years later by a myelopathy. MRI in both cases showed multifocal white matter abnormalities. The nosological interpretation of such cases remains uncertain: association of Eale's disease with multiple sclerosis or vasculopathy involving the central nervous system and the retina?
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The authors present four cases of tuberous sclerosis examined with MRI. The patho-anatomic aspects are reviewed and analysed with respect to MRI data. MRI appears superior to the CT particularly for imaging of cortical tubers, cystic lesions, and heterotopic clusters; these last two features were never described with MRI before. Here is also presented the second progressive case of giant intracranial aneurysm associated with tuberous sclerosis.
Ultrastructural lesions of the liver were studied in 12 cases of hairy cell leukemia, with the alterations of the sinusoidal barrier receiving special emphasis. Portal and sinusoidal tumoral infiltration was observed in all cases. It was associated with angiomatous lesions of the sinusoids in eight cases; these lesions consisted of randomly distributed cavities lined by hairy cells and containing hairy cells and erythrocytes. In addition to the attachment of hairy cells to the sinusoidal wall, other striking electron microscopic abnormalities of the sinusoids included 1) wide areas of communication between the sinusoidal lumen and Disse's space, allowing extravasation of blood cells; 2) focal disruption of the sinusoidal wall; and 3) replacement of the sinusoidal cell lining by tumor cells in close contact with hepatocytes. Most of these changes closely resembled those observed in peliosis hepatis. As in peliosis, sinusoidal alterations in hairy cell leukemia might be due to the destruction of the sinusoidal wall, and tumor cells could play a role in the pathogenesis of the lesions. The pattern of liver involvement in hairy cell leukemia, which is peculiar among hepatic localizations of blood malignancies, might reflect the unique phenotype of the tumor cells.
Thirty-two patients suffering from subepidermal autoimmune bullous disease were studied prospectively by clinical examination and immunoelectron microscopy. Clinically, 1 patient had herpes gestationnis, 14 typical bullous pemphigoid (BP), 3 epidermolysis acquisita (EBA), 3 cicatricial pemphigoid (CP), and 11 patients overlapping clinical diseases. These 11 patients shared clinical features of BP, EBA, or CP and a clinical diagnosis could not be done safely. Immunoelectron microscopy revealed diaminobenzidine deposits in 20 patients on the epidermal side of dermo-epidermal junction in the lamina lucida as in BP. In 5 patients, deposits located mostly under the anchoring fibril zone, in the floor of a sublamina densa dermoepidermal separation for 2 of them, were consistent with a diagnosis of EBA. In 6 patients, deposits were located mostly in the lamina densa, in the floor of a dermoepidermal separation occurring in the lamina lucida for 3 of them. This suggests that some of these 6 patients had neither EBA or BP, but another autoimmune bullous disease again, an uncharacterized component of dermoepidermal junction located in the lamina densa. Finally, a correlation exists between the sites of IgG and/or C3 components on epidermal or dermal side of dermoepidermal junction and the presence or absence of characteristic clinical features such as scar, milia formation, or mucosal involvement.
An investigation of the psychological characteristics of 44 children aged 6-16 years with documented evidence of idiopathic infantile hypercalcaemia revealed cognitive abilities and behavioural patterns which distinguish these children from other mentally handicapped groups. The children were all mildly to severely mentally handicapped, but exhibited superior verbal skills compared to their visuo-spatial and motor abilities. They showed high rates of behavioural disturbance, particularly in terms of hyperactivity, social isolation, anxiety, and eating and sleeping difficulties. Other aspects of behaviour, spoken language and personality that were commonly encountered are also described and quantified. From these observations approaches to remedial teaching are suggested.
The pharmacokinetics of naproxen have been examined in 13 elderly patients (mean age 84.2 years) and in 9 younger patients (mean age 53.9 years) at the end of a 21 day course of therapy with naproxen 500 mg b.d. The mean pre-dose concentration on days 19, 20 and 21 was significantly higher in the elderly patients than in the controls (60.1 vs. 43.3 micrograms X ml-1). The AUC (0-24) was significantly higher in the elderly subjects only when normalized for body weight (9.1 vs. 5.4 micrograms X ml-1 X h kg-1 p less than or equal to 0.02). The AUC was significantly higher in the elderly group compared to the control group also in the normalized form. The apparent clearance of naproxen was reduced in the elderly compared to the control patients (315 vs. 628 ml X h-1). The percentage protein binding of naproxen was the same in both groups (99.8%) but the free concentration of naproxen was significantly higher in the elderly patients than in the control patients (141 vs. 89.8 ng X ml-1). Although there was no excess of side effects in the elderly patients it is suggested that when naproxen is given to elderly patients, therapy should be started at the lower end of the dosage range.