Serum MBP immunoreactivity and immunoglobulin level as markers of tumour type

Summary Forty three patients, admitted to the department of Neurological Surgery for management of central nervous system tumours, were studied pre-operatively for serum myelin basic protein immunoreactivity as a marker of central nervous system lesion and for circulating immunoglobulins and complement (C₃) levels. Myelin basic protein concentration did not appear to correlate with tumour type or grade. Serum immunoglobulin levels were found to be within the normal range but the mean IgM level was significantly higher in the glioma group when compared with meningiomas.     

Identification of some plasma membrane proteins of cultured rat pigment epithelial cells by labeling with 125I

Cultured rat retinal pigment epithelial (PE) cells were labeled with 125I by lactoperoxidase (LPO)-catalyzed radioiodination. Examination of 125I-labeled cells by electron microscopic autoradiography suggested that 125I was incorporated into proteins at both the apical and basal surfaces of the PE cells, and into the extracellular matrix (ECM). Analysis of labeled cells by SDS-polyacrylamide gel electrophoresis and autoradiography showed that 125I was incorporated into at least 15 polypeptides. In order to determine which of these labeled proteins were derived from the plasma membrane. 125I-labeled cells were subjected to differential detergent extraction. Triton X-100 (2% v/v), which removed the cell plasma membrane, solubilized only three of the labeled proteins (152 000, 138 000, 123 000 daltons). SDS (0.25% w/v) completely removed cells from the tissue culture dish and solubilized all but four of the labeled proteins (225 000, 173 000, 87 000 and 72 100 daltons). When 125I-labeled PE cells were mechanically disrupted, and the resulting cell fractions separated by sucrose density gradient centrifugation, labeled proteins separated into two subcellular fractions. One fraction was especially enriched in the 152 000, 138 000 and 123 000 dalton labeled proteins, in addition to the plasma membrane marker enzymes Na+, K+-ATPase, and alkaline phosphodiesterase I. The second fraction was enriched in the 225 000, 196 000 and 173 000 dalton labeled proteins, the ECM proteins laminin and fibronectin, and the 43 000 actin band . It is proposed that 125I-labeled proteins in the former cell fraction are truly plasma membrane proteins, while those found in the latter cell fraction are a mixture of 125I-labeled ECM and basal plasma membrane proteins. The 152 000, 138 000 and 123 000 dalton labeled proteins of the plasma membrane fraction are glycoproteins and become firmly anchored to the Triton X-100 insoluble cytoskeleton when labeled cells are treated with concanavalin A.     

Pleural flap closure of pericardial defects following intrapericardial pneumonectomy.

Persistent pericardial defects following intrapericardial pneumonectomy are, historically, the major cause of iatrogenic cardiac herniation. This complication is uniformly fatal when unrecognized and untreated and has been associated with a 43% mortality even with surgical correction. Suture approximation of all small defects is recommended, and a technique for routine pleural flap closure of moderate to large-sized defects is described.     

Transfer of state-dependent control of discriminative behaviour between subcutaneously and intraventricularly administered nicotine and saline

Rats were trained to choose between the side compartments of a three-chambered shock-escape apparatus according to whether they were injected with nicotine or saline. Half of the rats learned to discriminate between 0.4 mg/kg nicotine and saline administered subcutaneously, whereas the other half learned to differentiate between 644 ng nicotine or saline administered intraventricularly. The rats trained by the subcutaneous route of administration had the ability to discriminate between nicotine and saline given intraventricularly and the rats trained by the intraventricular route could differentiate when the two substances were injected subcutaneously. This transfer of state-dependent control of discriminative behaviour between subcutaneously and intraventricularly administered nicotine and saline is presented as evidence for the central origin of the nicotine-produced interoceptive cue.This work supported by a grant from the American Medical Association Education and Research Foundation.     

Ocular findings in a newborn with cri du chat syndrome.

A deletion of the short arm of chromosome No. 5 has been termed the cri du chat (cat cry) syndrome. We report the first ophthalmologic examination of a newborn infant with this syndrome. Multiple ophthalmic abnormalities were found, including hypertelorism, telecanthus, epicanthal folds, antimongoloid palpebral fissures, exotropia, optic atrophy, and tortuosity of the retinal vasculature. It is of interest that these changes are congenital and present at birth, rather than developmental. Although such individuals are usually so severely mentally retarded that no ophthalmologic intervention is indicated, there are rare exceptions, and each case must be judged individually. Ten percent to 15% of these children inherit the chromosomal abnormality from phenotypically normal parents. Chromosomes from each parent should therefore be evaluated for the purposes of genetic counseling.     

Changes in beta-adrenoceptor-blocking activity produced by chemical modifications in the practolol molecule

Following administration of an acute dose of l-dopa (200 mg/kg i.p.), the concentration of this aminoacid increased rapidly in whole rat brain, to 10 μg/g and this new level was maintained for at least 20 min. At the same time, there was a significant (p < 0.01) depletion of brain serotonin (5HT), which was correlated with the level of dopa in the brain. The level of brain tryptophan (TP) also decreased. If l-dopa was given orally at a dose of 250 mg/kg, an increased concentration of this drug in the brain was still seen but the levels reached were 20 times less than the levels obtained after i.p. administration. In this situation the brain levels of 5HT and TP were unchanged. The chronic administration of l-dopa did not cause accumulation of the drug in the brain nor did it affect the concentration of 5HT and TP.     

Intraventricular bleeding from cerebral aneurysmal rupture

Summary Aneurysms rupturing into the ventricles have been shown at postmortem but rarely during angiography. Factors incriminated have been the high pressure during injection, the amount of contrast material, the proximity of site of injection to the aneurysm or a combination of more than one factor. We personally think it is unrelated to any of these factors, but rather a coincidental happening. The value of early angiography and delayed films is emphasized.

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Intraventrikuläre Blutung von einem rupturierten cerebralen Aneurysma

Zusammenfassung Bei der Ruptur eines Aneurysmas während der Angiographie werden verschiedene Faktoren für diese Ruptur herangezogen. Es soll sich dabei um den hohen Injektionsdruck handeln, um die Menge des Kontrastmittels oder um Kombination von mehreren Faktoren. Die Autoren sind der Ansicht, daß es sich jedoch um ein rein zufälliges Zusammentreffen handelt.

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Hémorragie intra-ventriculaire par rupture d'un anévrisme cérébral

Résumé Les ruptures d'anévrisme dans les ventricules ont été démontrées post-mortem et plus rarement au cours d'une angiographie. Les facteurs mis en cause sont la pression élevée durant l'injection, la quantité du produit de contraste, la proximité du point d'injection avec le siège de l'anévrisme ou l'association de plusieurs facteurs. Les auteurs pensent qu'on ne peut incriminer aucun de ces facteurs et qu'il s'agit plutôt d'une coincidence. II souligne la valeur de l'angiographie précoce et de l'étalement des films dans le temps.