Sodium Channel Gene Mutations in Children with GEFS+ and Dravet Syndrome: A Cross Sectional Study

 How to Cite This Article: Tonekaboni SH, Ebrahimi A, Bakhshandeh Bali MK, Houshmand M, Moghaddasi M, Taghdiri MM, Nasehi MM. Sodium Channel Gene Mutations in Children with GEFS+ and Dravet Syndrome: A Cross Sectional Study. Iran J Child Neurol. 2013 Winter; 7 (1):25-29. Objective Dravet syndrome or severe myoclonic epilepsy of infancy (SMEI) is a baleful epileptic encephalopathy that begins in the first year of life. This syndrome specified by febrile seizures followed by intractable epilepsy, disturbed psychomotor development, and ataxia. Clinical similarities between Dravet syndrome and generalized epilepsy with febrile seizure plus (GEFS+) includes occurrence of febrile seizures and joint molecular genetic etiology. Shared features of these two diseases support the idea that these two disorders represent a severity spectrum of the same illness. Nowadays, more than 60 heterozygous pattern SCN1A mutations, which many are de novo mutations, have been detected in Dravet syndrome. Materials & Methods From May 2008 to August 2012, 35 patients who referred to Pediatric Neurology Clinic of Mofid Children Hospital in Tehran were enrolled in this study. Entrance criterion of this study was having equal or more than four criteria for Dravet syndrome. We compared clinical features and genetic findings of the patients diagnosed as Dravet syndrome or GEFS+. Results 35 patients (15 girls and 20 boys) underwent genetic testing. Mean age of them was 7.7 years (a range of 13 months to 15 years). Three criteria that were best evident in SCN1A mutation positive patients are as follows: Normal development before the onset of seizures, onset of seizure before age of one year, and psychomotor retardation after onset of seizures. Our genetic testing showed that 1 of 3 (33.3%) patients with clinical Dravet syndrome and 3 of 20 (15%) patients that diagnosed as GEFS+, had SCN1A mutation. 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Evaluation of leishmanicidal effect of Euphorbia petiolata extract by in vivo anti-leishmanial assay using promastigotes of Leishmania major

Objective: The extract of different species of Euphorbia has been successfully used as a remedy for treatment of cutaneous leishmaniasis. The aim of this study was to assess the in vitro leishmanicidal effect of Euphorbia petiolata (E. petiolata) extract. Materials and Methods: Ethanolic percolated and methanolic Soxhlet extract of E. petiolata on promastigotes of L. major at different concentrations of extracts, one positive control group and one negative control group as well as 1 solvent control were prepared and placed in 24-well plates that contained 40,000 parasites/well. Afterwards, plates were incubated at 25 ˚C for six days and number of parasites in each well were determined on days 2, 4 and 6 of the experiment. Results: Both percolated and Soxhlet extracts in methanol and DMSO solvents had significant effects (equal to that of amphotericin B) on promastigote form of parasite at the concentration of 1 mg/ml. At lower concentrations, the extracts of E. petiolata had favorable leishmanicidal activity and killed L. major promastigotes dose-dependently. Conclusion: Our results support the possibility of E. petiolata extracts application as an anti-leishmanial agent with similar effects to amphotericin B

Physical properties, optical band gaps and radiation shielding parameters exploration for Dy³⁺-doped alkali/mixed alkali multicomponent borate glasses

Six compositions of 1 mol % Dy³⁺-doped multicomponent borate glasses containing single Li₂O, Na₂O, K₂O and mixed Li₂O–Na₂O, Li₂O–K₂O, and Na₂O–K₂O oxides have been synthesized by well-known melt-quenching technique. Following the measured density and refractive index values, various physical parameters were estimated for all the glass samples and differences in them are correlated with structural changes. To explore optical properties like absorption edge (λcut-off), optical band gap energy (Eopt), and Urbach energy (ΔE), optical absorption spectra were recorded for all the glasses. The Eg has been calculated using Davis and Mott theory for direct allowed, and indirect allowed transitions and the results were reported. The Eg values are also estimated using absorption spectrum fitting (ASF) method. The optical parameters variations have also been associated with the structural changes occurring in the glasses with different alkali/mixed alkali oxides content presence. The shielding properties of the prepared glasses were studied in terms of effective atomic numbers (Zeff), mean free path (MFP), half value layer (HVL) and macroscopic effective removal cross-section (ΣR). From these results, it was found that Potassium (K) glass shows superior gamma ray shielding properties due to a higher value of Zeff and lower values of both MFP and HVL. These results indicate that the prepared glasses might be utilized in place of some common shielding materials to shield γ-rays and neutrons

Development of SAC–OCDMA in FSO with multi-wavelength laser source

We propose and demonstrate a free space optical network, based on spectral amplitude coding optical code division multiple access (SAC–OCDMA) with a multi-wavelength laser source. A detailed theoretical analysis that represents the characteristics of SAC–OCDMA system was developed. In addition to the impact of turbulence, influences of several system noises such as optical beat interference (OBI), relative intensity noise, and receiver noises, have been studied. From the numerical results, it was found that the influence of OBI is more dominant, especially at higher received power. Two different codes, namely, modified quadratic congruence and modified double weight, are then compared with the latter which provides better performance. A transmission distance of 2.6 km with 10 users and an 8 cm aperture diameter is advisable whenever the turbulence is moderate. These results can be improved when a beam divergence smaller than 1 mrad is utilized