Objective To study the effect of different types of supernatants fluid of retinal cells on the physiological function of neuron cells derived from embryonic stem cells. Methods Embryonic bodies were sub-induced by retinoic acid (group A), retinoic acid with the supernatant fluid of retinal glia cells and neurons of mouse (group B), retinoic acid with the supernatant fluid of fetal retinal glia cells (group C), respectively. The Sodium ion channels on the cytomembrane in the 3 groups were analyzed 5-21 days after the inducement. Results The sodium current in each group didn't change much 5-21 days after the inducement. The sodium channels presented burst-opening discharge in group A, brief-opening discharge in group B, and long-opening discharge in group C. The percentage of the cells without current in group A, B and C was 25%, 11.4%, and 23.8%, respectively, but the difference was not significant among the 3 groups(Pgt;0.05). The number of cells with sodium current increased at first and decreased later in group A, continuously increased in group B, and decreased at first and kept stable later in group C. The open time of sodium channels was the longest in group A, and the shortest in group B. The distribution of open time in the three groups could be managed with two-step exponential fit. Conclusion The supernatant fluid of retinal cells has apparent influence on the physiological function of the neuron cells derived from embryonic stem cells. (Chin J Ocul Fundus Dis, 2007, 23: 91-93)
ObjectiveTo explore the molecular characteristics of partial epilepsy with febrile seizures plus(PEFS+). MethodsWe systematically reviewed all SCN1A mutation-related publications that published between Jan.2000 and Dec.2014 on Pubmed and established a database of SCN1A mutations (http://www.gzneurosci.com/SCN1Adatabase/). The characteristics of mutations that cause PEFS+ were analyzed and compared with that of severe myoclonic epilepsy in infancy (SMEI). ResultsThe database included 1, 257 SCN1A mutations, which identified from 1, 727 unrelated cases. In which there were 30 mutations, from 32 unrelated cases, were associated with PEFS+. 76.7% (23/30) mutations were missense, of which 47.8% (11/23) were located on pore region. Significant difference in the percentage of truncation mutation was observed between PEFS+ and SMEI (P < 0.05). There was no significant difference in the percentage of missense mutation that located on the pore region between PEFS+ and SMEI; but the differ significantly in D-value of the missense mutations, which quantified the alteration of amino acid(P=0.042, rank sum test). ConclusionsPEFS+, which distinguishes from GEFS+ and SMEI in clinical and molecular characteristics, is a special phenotype of epilepsy that is associated with SCN1A mutations.