Neurologic disorder of vitamin E deficiency in acquired intestinal malabsorption.

Fifteen years after onset of a malabsorption syndrome, a 49-year-old man had sensory and oculomotor disorder with marked vitamin E deficiency. After 6 months of treatment with high parenteral doses of vitamin E, the neurologic signs slowly receded, but the patient died of gastrointestinal hemorrhage. Autopsy and sural nerve biopsy showed the changes in both central and peripheral nerves; these changes are considered characteristic of vitamin E deficiency.

In vitro propagation of Petasites hybridus (Asteraceae) from leaf and petiole explants and from inflorescence buds.

In vitro shoot regeneration from sterile leaf and petiole explants and from in-situ-collected inflorescence buds of Petasites hybridus was achieved by a simple two-step protocol. Murashige and Skoog (MS) nutrient medium was supplemented with 17.6 µM benzyladenine (BA)+0.54 µM naphthaleneacetic acid (NAA) to induce shoots. After 5 weeks of culture, 40% of the petiole and 27% of the leaf explants produced shoots compared to 76% of the inflorescence buds. Single shoots were excised and subcultured on MS medium supplemented with various cytokinins (N6-(Δ2-isopentenyl)adenine, BA, kinetin and thidiazuron). A concentration of 8.8 µM kinetin+0.54 µM NAA performed best in terms of shoot multiplication rate, average shoot length and spontaneous root induction.

Immunopathological changes in human cerebral malaria.

Pathogenic mechanisms in human cerebral malaria remain unclear. We reevaluate the role of cell-mediated immune mechanisms in the pathogenesis of this disease based on autopsy findings in a 34-year-old Caucasian male. Histologic examination of brain tissue showed typical features of severe malaria infection (sequestration of Plasmodium falciparum-infected erythrocytes in vessels, cerebral oedema, petechial lesions and Dürck granulomas). In addition to these classical changes, we found that leukocytes that stained positively in immunohistochemistry for CD68 and tumor necrosis factor-alpha (TNF) coexisted with infected erythrocytes in capillaries, whereas in venules the monocyte population outnumbered the erythrocytes. Notable expression of ICAM-1 on endothelial cell surface was detected by immunohistochemistry in vessels with sequestered cells but not in unaffected vessels. These changes are identical to those of the murine model of the disease, in which cell-mediated immune mechanisms and TNF have been implicated. In vitro, ICAM-1 has been shown to be a potential ligand for P. falciparum-infected erythrocytes. In malaria patients, high serum TNF levels, which have been detected in close correlation with disease severity, may thus favor adhesion to endothelial cells of either red or white blood cells via enhanced ICAM-1 expression. The present observations are further evidence for a role of cell-mediated immunity in the pathogenesis of human cerebral malaria.

[Porto-systemic encephalo-myelopathy]. / L'encéphalo-myélopathie porto-systémique

To avoid the dangerous consequences of gastro-intestinal haemorrhages in portal hypertension, portosystemic anastomosis is often performed. These operations unfortunately cause numerous complications among which isolated encephalopathy and encephalo-myelopathy hold pride of place. In spite of their different clinical, biological, therapeutic and anatomo-pathological behaviour, these two complications are undoubtedly the result of a common pathogenesis of which the details are not at present understood. It is, however, known that these involve complex metabolic disorders connected with the direct passage into the caval blood of products from the gut (ammonia, false neurotransmitters, ...). Experiments with rats have shown development of type II Alzheimer glia in the cerebellum after portocaval anastomosis; so far, spinal lesions have not been reproduced (10-76). In conclusion, it must be recognized that, as Lucien Leger (39) wrote, "by creating a new physiopathology, portal decompression raises as many questions as it solves."

[Endocarditis, brain lesions and anticoagulants (anatomic clinical and statistical study of 229 cases)]. / Endocardites, lésions cérébrales et anticoagulants (étude anatomo-clinique et statistique de 229 cas).

This study of brain autopsy findings in 229 cases of endocarditis (67 anticoagulated, 162 non-anticoagulated) shows that treatment with anticoagulation does not increase the incidence of cerebral hemorrhage, neither from the conversion of ischaemic necroses into hemorrhagic ones nor from an increase in other circulatory or vascular lesions. The analysis was based on the pathogenesis and detailed descriptions of the lesions, paying particular attention to hemorrhagic infarctions of the cerebral cortex. Using chi-square analysis, there was no significant difference between the frequency of lesions in anticoagulated versus non-anticoagulated patients.

[Spontaneous dissecting aneurysm of the internal carotid artery. General review of 205 published cases with 10 personal cases]. / L'hématome disséquant spontané de l'artère carotide interne. Revue générale de 205 cas publiés dont 10 personnels.

Spontaneous dissecting aneurysms of the internal carotid artery occur almost exclusively in the extracranial segment of the artery. The incidence is higher among males and the average age is relatively low (mean: 45 years). The existence of a lesion involving the wall of the carotid artery must be considered in the patient presenting with atypical facial neuralgia or incomplete but painful Horner's syndrome which may or may not be associated with a controlateral neurological deficit. Spontaneous dissecting aneurysms of the internal carotid artery cannot be diagnosed on the basis of a single angiogram. Definite diagnosis requires repeated ultrasonography and/or angiography. Spontaneous recanalization justifies the use of medical therapy (anticoagulant or antiplatelet aggregation therapy) in preference to surgical intervention.

[Incidence of chondrocalcinosis in a series of 1,000 surgically excised intervertebral disks]. / Fréquence de la chondrocalcinose dans une série de 1000 disques intervertébraux excisés chirurgicalement.

This study is based on the histological examination of a series of 1000 intervertebral discs which were excised surgically for a painful spinal or nerve root syndrome. The authors observed in 31 cases (18 men and 13 women) a chondrocalcinosis that was not found clinically (small circumscribed deposits of crystals identified as calcium pyrophosphate after examination in compensated polarized light microscopy). The frequency is higher than that of chondrocalcinosis observed in the menisci excised surgically from the knees of subjects with the same average age; but it is lower than that for the menisci taken from autopsy material of subjects with a higher average age. The histological examination of all surgically excised discs would permit the findings of signs of chondrocalcinosis, thus emphasizing the risk for the patient of a further evolution to arthropathies (spinal or peripheral). This can offer bases for statistical longitudinal studies.

[Waldenstrom's macroglobulinemia with lymphorproliferative changes in the central nervous system. 4 cases]. / Macroglobulinémie de Waldenström avec atteinte lymphoproliférative du systéme nerveux central A propos de 4 cas anatomo-cliniques (1)

An anatomial-clinical description of 4 cases of Waldenström's macroglobulinaemia presenting specifically with meningo-cerebral involvement. The lesions in the central nervous system included lymphocytic infiltrations predominantly in the meso-diencephalic region in two cases, a diffuse meningo-encephalic in the third and a primary malignant cerebral lymphoma in the fourth case. The neurological complications of the disease, the cerebro-spinal fluid findings, theories of pathogenesis and the therapeutic possibilities are reviewed. A particular interest is taken concerning the diagnosis from clinical findings due to specific lesions for which one must reserve the name of "Bing-Nell syndrome". Taking the case of primary cerebral lymphoma, similarities between the pathology of the meningo-cerebral lympho-reticular system and other immunologic disorders have been considered. It is suggested that, through this system, the brain can activily participate in the histopathological manifestations of Waldenström's macroglobulinaemia just as any of the other organs of the body.

[Progressive encephalopathy in 3 cases of chronic lymphoid leukemia]. / Encéphalopathie progressive dans trois cas de leucémie lymphoïde chronique.

Three patients suffering from a lymphoproliferative syndrome developed, late in the course of the disease, a neurological disorder with the signs and symptoms of a progressive multifocal leukoencephalopathy (PML). This diagnosis was confirmed in the first patient. In the second, neuropathological examination revealed spongy and fibrous scars which could be evidence of an earlier lymphomatous infiltration. The diagnosis of the third patient was uncertain since no autopsy was made in this case. The involvement of the CNS in the evolution of lymphoproliferative disorders becomes more and more frequent, probably due to the prolonged survival time of patients undergoing chemotherapy and the immunosuppressive effects of such treatment. Biopsy is the only method of distinguishing PML from a cerebral leukemic infiltration; this is obviously important in view of the different therapeutic approaches used for the two diseases.

Quantitative analysis of petasin and pyrrolizidine alkaloids in leaves and rhizomes of in situ grown Petasites hybridus plants.

Various locations in Switzerland were screened for Petasites hybridus plants with high petasin and low pyrrolizidine alkaloid content. The mean petasin content of the various populations ranged from 7.4 to 15.3 mg/g dry weight in rhizomes and from 3.3 to 11.4 mg/g dry weight in leaves. Mean pyrrolizidine alkaloid content in rhizomes ranged from 5 to 90 ppm whereas leaves contained between 0.02 to 1.50 ppm. These results suggest that leaves might be a preferable source for harvesting compared to the underground organ due to the finding of high petasin contents and consistently lower amounts of toxic pyrrolizidine alkaloids.

Totally implantable dimension telemetry.

A totally implantable dimension telemetry system has been developed to instrument animals for chronic physiological research. Implantable signal processing electronics allow free-roaming animals with no percutaneous leads while retaining the long-term redproducibility of fixed implanted transducers. Two low-powered, custom-integrated circuits have been developed and assembled into an implantable package capable of measuring one dimension channel. The system has been operated in the amplitude modes of through-transmission and reflection as well as in a new Doppler-power configuration and aimed at determining interfaces between blood and surrounding structures. In a addition to single channel systems, these ICs are key elements in multimode, multidimensional implants capable of more accurate characterization of deep body structures.

Influence of 13-cis and all-trans retinoic acid on rat embryonic development in vitro: correlation with isomerisation and drug transfer to the embryo.

In vitro experiments using whole rat embryo cultures show that all-trans retinoic acid (all-trans RA) administered at low concentrations (30 ng/ml culture medium) is 10 times more active than 13-cis retinoic acid (13-cis RA) and 3 times more active when administered at high concentrations (1000 ng/ml culture medium). Morphological investigation of the embryos shows that both substances directly influence embryonic development in an identical manner. Isomerisation products of the administered compounds (all-trans RA from 13-cis RA and vice versa) were detected by HPLC both in the culture medium and the embryo. Correlation of embryonic retinoid concentration with the observed effects led us to suggest that the isomerisation to all-trans RA is crucial in regard to 13-cis RA-induced abnormal embryonic development. A 100% effect can be induced in vitro with very low amounts of all-trans RA (7.2 ng/g) in the embryo.