Unrecognized aneurysms of the circle of Willis]

The authors present, among 200 intracranial arterial aneurysms, 13 cases where the angiographic diagnosis of the aneurysm had been difficult. Among them, there were ten mistakes through default, and four mistakes through excess. Angiographic studies were done early, about the third day following subarachnoidal hemorrhage, so that conscious patients may have rapid surgery. The main diagnosis defaults were observed in aneurysms of the anterior communicating artery (cases 1, 2, 3, 4, 6), where the flexurae and arterial anomalies explain the diagnostic mistakes; double anterior cerebral artery, median anterior cerebral artery of Lazorthes, early origin of the frontopolar artery or of the callosomarginal artery. The aneurysms of the posterior wall of the carotid bifurcation, were hidden by this artery in the A.P. view and by the middle cerebral artery in the profile view (cases 5 and 7). Oblique views are necessary for the two localizations of these aneurysms. The middle cerebral aneurysms (case 8) may be hidden by a bony superposition. The Ziedses des Plantes subtraction method obviates this diagnostic default. Aneurysms of the peripheral branches of cerebral arteries (case 9) are filled later and slightly. Aneurysms of an artery less than 3 mm wide (posterior communicating artery, lenticular artery) are difficult to discriminate from their enlarged infundibulum (case 10). The small size of the aneurysm is not the only explanation of the difficult diagnosis. Indeed, few aneurysms are not evidenced by the first angiography, done at an early stage, even if any spasms exist. Only repeated angiographies could show the aneurysm particularly in young people. We repeat the angiography 15 to 20 days after the first one, and even some months later. In two young patients, angiographic studies were repeated a few times in three years and were normal; but after four years in one case and five years in the other, a new subarachnoidal hemorrhage occurred, and only then was the aneurysm shown by a new angiography (cases 4 and 5). In our series, the angiographic spasm could not afford an explanation for the diagnostic default. This, soon after the subarachnoidal hemorrhage, might be explained by the hemostatic clot which compresses or plugs the aneurysm. Further, the clot's lysis occurs, and the aneurysm can be evident. A double conlcusion must be drawn: --first, the angiography must be repeated if the image is dubious; the angiographic technique must be perfect and varied (oblique view, subtraction method, enlargement technique). Mistakes through excess, leading to useless operations, are as dangerous as mistakes through default; --secondly, great care should be exerted when reading and interpreting the X-ray films in the post-operative period in order to evaluate the surgical results, as well as in the preoperative period.     

The inhibition of fatal graft-versus-host disease by immunization of donor or host with bacillus Calmette-Guérin cell walls

F1 mice receiving sublethal whole-body x-irradiation (300 rads) or treatment with cyclophosphamide prior to the i.p. inoculation of parental spleen cells developed fatal graft-versus-host disease (GVHD). A greater survival rate was obtained when the inoculated parenteral spleen cells were obtained from BCGcw-preimmunized donors. The immunization of the F1 host with bacillus Calmette-Guerin cell walls (BCGcw) also increased host survival. The combined treatment of preimmunizing the host with BCGcw and of using spleen cells from BCGcw-immunized parental donors to initiate the GVHD resulted in producing the least severe GVHD and the greatest overall survival. The systemic transfer of x-irradiated spleen cells from BCGcw-immunized parental mice inhibited the fatal GVHD induced by the inoculation of normal parental spleen cells. These studies show that BCGcw immunization of the host or obtaining parental spleen cells from BCGcw-immunized animals resulted in improving the overall survival rate in graft-versus-host disease. BCGcw immunization induces suppressor cells and the decrease of graft-versus-host disease that was observed was most likely due to the induction of suppressor cells.     

Levamisole in chronic lymphocytic leukaemia: a prospective study of 15 patients

Several haematological and immunological parameters were studied before and after a 4-week trial of oral levamisole (300 mg/week) in 15 patients with chronic lymphocytic leukaemia. We found no statistically significant difference in the mean peripheral blood counts of total lymphocytes, E-rosette-forming lymphocytes, monocytes, polymorphonuclear neutrophils, eosinophils and platelets. Mean serum levels of IgG, IgA, IgM, IgD, C3 and C4 were not statistically affected by levamisole nor was the mean lymphocyte stimulation modified by various mitogens (phytohaemagglutinin, concanavalin A, pokeweed mitogen, tuberculin, candidin). The mean IgE level was statistically increased (p less than 0.05) after levamisole administration but remained below the normal upper limit. A high rate (46%) of clinical and haematological adverse reactions (1 patient developed thrombocytopenia) was associated with levamisole administration. These results suggest that levamisole, as given in this trial, has no obvious beneficial effect and cannot be recommended in patients with chronic lymphocytic leukaemia.     

X-ray microanalysis as applied to fungal tissues

Analytical electron microscopy combines the techniques of high-resolution electron microscopy and high-sensitivity X-ray microanalysis of samples. Spectrometry of the elements (characteristic X-rays produced by a scanning electron microprobe) was employed to detect some elements of Mendeleev's classification in pathogenic fungi for humans. X-ray microanalysis applied in wavelength dispersive spectrometry was used to study Coccidio?des immitis, Paracoccidio?des brasiliensis and Trichosporum cutaneum.     

Continuous and intermittent levodopa differentially affect basal ganglia function

The effects of continuous and intermittent levodopa treatment on behavioral and biochemical indexes of basal ganglia function were compared in rats with unilateral 6-hydroxydopamine lesions of the nigrostriatal dopamine pathway. Animals treated for 30 days with intermittent levodopa exhibited behavioral sensitization manifested by an enhanced rotational response to apomorphine; the rotational response of rats treated with an equivalent dose of levodopa by continuous infusion did not differ from that of saline-treated controls. Dopamine receptor up-regulation in the denervated striatum relative to the intact striatum was statistically significant for D1 but not D2 receptors: This asymmetry in dopamine receptor levels was diminished following intermittent levodopa treatment. Glutamic acid decarboxylase activity, modestly elevated in all groups in the denervated striatum relative to the intact striatum, increased substantially over control values bilaterally as a result of intermittent, but not continuous, levodopa treatment. These findings suggest a relation between the schedule of chronic levodopa administration and the development of behavioral sensitization, possibly as a consequence of alterations in neuronal systems located downstream from striatal dopamine receptors. The behavioral sensitization induced by chronic, intermittent dopaminomimetic treatment may serve as a model for motor fluctuations in Parkinson's disease.     

Lasers as tools for mycology.

Methods of preparing fungal samples for chemical analysis are briefly considered. The basic principles employed in laser microscopy are outlined. The applications of the technique to mycology and to plant biology are discussed. Such a method allows chemical information to be obtained on the same sample and permits the detection of 74 elements in the periodic system of Mendeleev from lithium (3) to uranium (92). The preparative procedures are evaluated according to general histochemical principles. This technique requires little specimen preparation and has the advantage of not requiring large masses of tissue.