Deep brain stimulation in Bassen-Kornzweig syndrome: Still effective after 22 years.

Introduction: Bassen-Kornzweig syndrome or abetalipoproteinemia is a rare autosomal recessive disorder characterized by a malabsorption of dietary fat and fat-soluble vitamins. This deficiency can lead to a variety of symptoms, including hematological (acanthocytosis, bleeding tendency), neurological (tremor, spinocerebellar ataxia), neuromuscular (myopathy), ophthalmological symptoms (retinitis pigmentosa). The thalamic ventral intermediate nucleus (VIM) is a well-established target for deep brain stimulation (DBS) in the treatment of refractory tremor. Research question: We evaluated the clinical long-term follow-up (22 years) after VIM-DBS for refractory tremor in abetalipoproteinemia. We also evaluated the adjustments of stimulation settings and medication balance after DBS procedure. Material and methods: We report a 53-year-old male who suffers from abetalipoproteinemia since the age of 17. He underwent bilateral VIM-DBS to treat his disabling refractory intentional tremor at the age of 31. He still has a very good response to his tremor with limited stimulation adaptations over 22 years. For more than two decades follow-up, the treatment significantly improved his ADL functions and therefore also the QoL. Discussion and conclusion: The VIM target for DBS in the treatment of refractory tremor has been extensively reported in the literature. Thalamic VIM-DBS is a safe and effective treatment for a severe, refractory tremor as a neurological symptom caused by abetalipoproteinemia. It also highlights the importance of a multidisciplinary follow-up, to adjust and optimize the stimulation/medication balance after VIM-DBS surgery.

Are spontaneous epidural haematoma in sickle cell disease a rare complication? A report of two new cases.

BACKGROUND: Sickle cell anaemia, an autosomal recessive disease relatively common among the black races, gives rise sometimes to neurological complications. Among these, spontaneous epidural haematoma constitutes a rare event that is not always easy to treat in the Third world conditions. METHODS: Two new cases are described and their pathology is compared with the five already described cases in the literature. A vaso-occlusive pathological process as in the orbital compression syndrome is thought to be implicated in the generation of the spontaneous epidural haematoma. RESULTS: When facing an epidural haematoma as a complication of sickle cell disease in a hospital of the Third world conditions, a cautious attitude towards surgery should be observed because of the high complication rate. If the relation between the haematoma and the anaemia is not immediately apparent, we are in favour of starting treatment with antibiotics.

The specificity of beta-galactosidase in the degradation of gangliosides.

Available evidence indicates that a least two genetically distinct acidic lysosomal beta-galactosidases are present in mammalian tissues. One of them, galactosylceramidase, is primarily responsible for degradation of galactosylceramide, galactosylsphingosine, and monogalactosyl-diglyceride, while the other, GM1-ganglioside beta-galactosidase, degrades GM1-ganglioside and asialo GM1-ganglioside. Lactosylceramide can be hydrolyzed by either of the two enzymes. These substrate specificities of the two beta-galactosidases can adequately explain the known findings in the two genetic beta-galactosidase deficiency diseases. The possibilities of the specific lactosylceramidase have not yet received the necessary independent confirmation.

Biosynthesis of ergothioneine from endogenous hercynine in Mycobacterium smegmatis.

Ergothioneine was synthesized and accumulated in growing cultures of Mycobacterium smegmatis when the medium was adequately supplied with sulfur. In a low sulfur medium, the accumulation was sharply limited although growth of the organism was apparently normal. Synthesis of hercynine, the precursor of ergothioneine, was unaffected by low sulfur levels and was markedly increased by addition of l-histidine, the precursor of hercynine. Resting-cell pellicle experiments, performed with cells grown on the low sulfur high histidine medium, showed that ergothioniene was synthesized from endogenous hercynine, when cysteine or compounds readily converted to cysteine (such as cystine, lanthionine, cystathionine, and thiazolidine carboxylic acid) were added. Homocysteine and djenkolic acid allowed for minimal synthesis of betaine, whereas methionine, S-methylcysteine, sodium sulfate, and sodium thiosulfate were unable to donate sulfur for ergothioniene synthesis under the experimental conditions employed. Addition of cysteine to a resting pellicle preparation caused the formation of 100 to 200 mug of ergothioneine per g of dry cells in 2.5 to 3 hr. A modified procedure for isolating ergothioneine and hercynine, employing a 75% ethyl alcohol extraction of wet organisms, followed by a single alumina column separation of the compounds, is described.