Mutations of SCN1B in Generalized Epilepsy with Febrile Seizures Plus(GEFS+) / 대한소아신경학회지

PURPOSE: Febrile seizures affect 2-5% of all children younger than 6 years old. A small proportion of children with febrile seizures later develop epilepsy. Generalized epilepsy with febrile seizures plus(GEFS+) is an important childhood genetic epilepsy syndrome with heterogeneous phenotypes, including febrile seizures(FS) and generalized epilepsies of variable severity. It was reported that the gene locus for GEFS+ exists in the chromosome 19q13.1, and has relationship with a 387 C->G mutation in the voltage- gated sodium channel beta1 subunit(SCN1B) gene. This study is to determine whether there are mutations in children with GEFS+ and FS. METHODS: Eighteen GEFS+ and thirteen FS patients were screened for mutations in the sodium channel beta-subunits SCN1B. The primer pairs used to amplify the exons of SCN1B are given in the supplementary data on the Neurology web site. All exons were amplified by PCR and PCR products were subsequently sequenced. Single-stranded conformation polymorphism(SSCP) was carried out using 8% polyacrylamide gel. RESULTS: Twenty four patients(77%) were younger than 10 years old, three(10%) were between 10 and 14 years old, and four(13%) older than 14 years old. The ratio of female to male was 0.55:1.0. In phenotypes of GEFS+, fourteen patients(88%) had generalized tonic-clonic seizures, one patient(6%) myoclonic seizures and one patient(6%) atonic seizures. In EEG findings of GEFS+, eleven(78%) patients had normal findings, five(28%) patients generalized spike waves and two patients(11%) diffuse slowings. In sequencing and SSCP of PCR products, we could observe added C mutations between 224G and 225C of exon 3 in two unrelated patients with GEFS+. CONCLUSION: We proved the existence of a new mutation of SCN1B in two unrelated patients with GEFS+.

A Case of Duplication 9p Syndrome: Partial Trisomy 9p

Trisomy 9p syndrome was first described by Rethore, et al in 1970 and about 150 cases have been reported. Trisomy 9p has been reported as either partial or complete. The term "duplication 9p syndrome" instead of "trisomy 9p syndrome" is used since most of the reported patients had only partial duplication rather than the whole arm duplication of 9p. Duplication of 9p syndrome is characterized by growth and developmental retardation, microbrachycephaly, deep and wide set eyes with down-slanting palpebral fissures, "globular" nose, down-turned corners of the mouth, prominent apparently low-set ears, and short fingers and toes with small nails. A 10- month-old male was referred to our department of pediatrics because of hypotonia and delayed development. Karyotype revealed 46, XY, dup(9)(p12p24) by GTC-Banding. We report a case of a duplication 9p syndrome diagnosed by GTC-banding.

Culturing Successfully Adult Schwann Cells from Peripheral Nerve of Rats / 대한소아신경학회지

PURPOSE: Schwann cells are difficult to isolate from adult mammalian peripheral nerves because of the abundant connective tissue and the highly differentiated state of the cells, particularly those involved in the formation of myelin. It has been shown that in vivo, both neurons and Schwann cells are conditioned by a nerve lesion, speeding up the Schwann cell proliferation and the neuronal regeneration. In this study with adult rat peripheral nerves, we report that a conditioning lesion increases Schwann cells and of cells which successfully attach to a tissue culture striatum. METHODS: The study was done with Sprague-Dawley male rats(250-300 g). Their left sciatic nerves were exposed, severed at the sciatic notch and deflected. After 14 days, with 20 mm segments the nerves were excised from the distal stump of the conditioned sciatic nerves. Schwann cells were cultured in RPMI-1640 media. The identity of the cells was verified with antibody staining using S-100. RESULTS: The lesion evoked a progressive and significant increase in the number of cells obtained as early as 48 hr of the plating, until day 12. Decreasing the duration of enzyme digestion to 3 and 4 hrs markely increased the number of attached Schwann cells. The peak numbers of attached Schwann cells was observed between day 12 and day 14 of the plating. Most attached Schwann cells had typical oval-shaped cell bodies, with prominent nuclei and bipolar cell extensions, resulting in overall spindle shapes. CONCLUSION: Our findings indicate that a conditioning lesion enables us to isolate and culture adult Schwann cells successfully from the peripheral nerves of rats.