Ultra-structure des corps de lafora

Neuropathological Studies in Three Scandinavian Cases of Progressive Myoclonus Epilepsy

“…Morphologically and histochemically, Lafora bodies are similar to the common amyloid bodies. Ultrastructural studies have, however, shown that amyloid bodies only occur i n astrocytes and never in nerve cells, while Lafora bodies are mainly or exclusively localized to neurons ( R a m s e y 1965, Toga et al 1968). In our cases numerous amyloid bodies were found, particularly in the spinal cord However, no inclusion bodies of the Lafora type were found in nerve cells and thus the cases cannot be included in the Lafora body group.…”

Loss of function of the cytoplasmic isoform of the protein laforin (EPM2A) causes Lafora progressive myoclonus epilepsy

“…Pathologic analyses reveal a disturbance of glycogen metabolism with formation and accumulation of abnormally branched glycogen molecules that aggregate near the endoplasmic reticulum (ER) into large dense inclusions known as Lafora bodies (LB) [Lafora, 1911;Collins et al, 1968;Toga et al, 1968;Sakai et al, 1970;Van Heycop ten Ham, 1974]. They also show an unusual nonapoptotic process of neurodegeneration, characterized by a generalized disintegration of cellular organelles [Collins et al, 1968;Toga et al, 1968;Ganesh et al, 2002a]. LD is caused by mutations of either the EPM2A gene (MIM# 607566) [Minassian et al, 1998[Minassian et al, , 2000Serratosa et al, 1999; Gomez-Garre et al, 2000; Ganesh et al, 2002a;Ki et al, 2003] or the EPM2B gene [Chan et al, 2003].…”

Epilepsia mioclónica progresiva tipo Lafora y los casos diagnosticados en Costa Rica

“…Su estudio por medio de microscopio electrónico indica que están hechos de fibras cortas de 50 a 100 Å de diámetro. Muchas fibras parecen estar en asociación física con el retículo endoplasmático o los ribosomas (Collins et al 1968, Toga et al 1968).…”

“…Lo más probable es que los CL se originen por un defecto en el metabolismo del glucógeno, porque no hay otra fuente de polímeros de glucosa en los tejidos animales (Roger et al 1967, Collins et al 1968, Toga et al 1968, Sakai et al 1970, Nikaido et al 1971, Nishimura et al 1980, Robitaille et al 1980, Hays et al 1981, Baumann et al 1983, Roger et al 1983, Busard y Renier 1986, Kobayashi et al 1990, Berkovic et al 1993, Drury et al 1993, Cavanagh 1999, Minassian et al 2000b.…”