Adjunctive levetiracetam treatment in pediatric Lennox-Gastaut syndrome

BACKGROUND

Our aim was to investigate the efficacy and tolerability of levetiracetam as an add-on treatment in pediatric patients with Lennox-Gastaut syndrome.

METHODS

The study was an open-label, multicenter, observational clinical trial of levetiracetam as an add-on treatment in Lennox-Gastaut syndrome. Fifty-five patients aged 1.1-18.6 years (mean, 10.0 years) were enrolled. The study included a 4-8-week titration period and an 8-week maintenance period. The maintenance dose of levetiracetam was 20-80 mg/kg/day, according to its effectiveness and tolerability. The primary end point was reduction in seizure frequency, and related variables were also evaluated.

RESULTS

Among 55 patents, 51 patients (92.7%) completed the study. Thirty-two patients (58.2%) experienced a more than 50% reduction in seizure frequency, and 15 patients (27.3%) became seizure free. A reduction in seizure frequency of more than 50% was observed in 21 of 36 patients (58.3%) with convulsive seizures, 7 of 12 patients (58.3%) with drop attacks, 2 of 4 patients (50.0%) with myoclonic seizures, and 2 of 3 patients (66.7%) with epileptic spasms. Overall, 34.5% of patients reported adverse events. None of the adverse events were life threatening, and the most common adverse event was hyperactivity (12.7%).

CONCLUSIONS

This study suggests that levetiracetam is a safe and effective treatment in pediatric patients with Lennox-Gastaut syndrome.

Epilepsy-related clinical factors and psychosocial functions in pediatric epilepsy

PURPOSE

The aim of this study was to identify the different influencing patterns of demographic and epilepsy-related variables on various aspects of psychosocial function in pediatric epilepsy.

METHOD

Five hundred ninety-eight patients with pediatric epilepsy between the ages of 4 and 18 years (boys=360, 60% and girls=238, 40%) and their parents participated in the study. Parents completed the Social Maturity Scale (SMS), the Korean version of the Child Behavior Checklist (K-CBCL), and the Korean version of the Quality of Life in Childhood Epilepsy Questionnaire (K-QOLCE) to assess daily living function, behavior, and quality of life. The Children's Global Assessment Scale (CGAS) was completed by clinicians to assess general adaptive function. Demographic variables, such as age and sex of child, and epilepsy-related clinical variables, including seizure type, seizure frequency, duration of epilepsy, and number of medications, were obtained from medical records.

RESULTS

Demographic and epilepsy-related clinical variables had a strong influence (22-32%) on the cognition-related domain such as general adaptive function, school/total competence, and quality of life for cognitive function while a comparatively smaller effect (2-16%) on the more psychological domain including behavioral, emotional, and social variables. Younger age, shorter duration of illness, and smaller number of medications showed a strong positive impact on psychosocial function in pediatric epilepsy, particularly for adaptive function, competence, and quality-of-life aspects.

CONCLUSION

Given the wide range of impact of demographic and clinical variables on various facets of psychosocial functions, more specific understanding of the various aspects of factors and their particular pattern of influence may enable more effective therapeutic approaches that address both the medical and psychological needs in pediatric epilepsy.

Polarized axonal surface expression of neuronal KCNQ potassium channels is regulated by calmodulin interaction with KCNQ2 subunit

KCNQ potassium channels composed of KCNQ2 and KCNQ3 subunits give rise to the M-current, a slow-activating and non-inactivating voltage-dependent potassium current that limits repetitive firing of action potentials. KCNQ channels are enriched at the surface of axons and axonal initial segments, the sites for action potential generation and modulation. Their enrichment at the axonal surface is impaired by mutations in KCNQ2 carboxy-terminal tail that cause benign familial neonatal convulsion and myokymia, suggesting that their correct surface distribution and density at the axon is crucial for control of neuronal excitability. However, the molecular mechanisms responsible for regulating enrichment of KCNQ channels at the neuronal axon remain elusive. Here, we show that enrichment of KCNQ channels at the axonal surface of dissociated rat hippocampal cultured neurons is regulated by ubiquitous calcium sensor calmodulin. Using immunocytochemistry and the cluster of differentiation 4 (CD4) membrane protein as a trafficking reporter, we demonstrate that fusion of KCNQ2 carboxy-terminal tail is sufficient to target CD4 protein to the axonal surface whereas inhibition of calmodulin binding to KCNQ2 abolishes axonal surface expression of CD4 fusion proteins by retaining them in the endoplasmic reticulum. Disruption of calmodulin binding to KCNQ2 also impairs enrichment of heteromeric KCNQ2/KCNQ3 channels at the axonal surface by blocking their trafficking from the endoplasmic reticulum to the axon. Consistently, hippocampal neuronal excitability is dampened by transient expression of wild-type KCNQ2 but not mutant KCNQ2 deficient in calmodulin binding. Furthermore, coexpression of mutant calmodulin, which can interact with KCNQ2/KCNQ3 channels but not calcium, reduces but does not abolish their enrichment at the axonal surface, suggesting that apo calmodulin but not calcium-bound calmodulin is necessary for their preferential targeting to the axonal surface. These findings collectively reveal calmodulin as a critical player that modulates trafficking and enrichment of KCNQ channels at the neuronal axon.

Protein Profile in Corpus Luteum during Pregnancy in Korean Native Cows

Steroidogenesis requires coordination of the anabolic and catabolic pathways of lipid metabolism, but the profile of proteins associated with progesterone synthesis in cyclic and pregnant corpus luteum (CL) is not well-known in cattle. In Experiment 1, plasma progesterone level was monitored in cyclic cows (n = 5) and pregnant cows (n = 6; until d-90). A significant decline in the plasma progesterone level occurred at d-19 of cyclic cows. Progesterone level in abbatoir-derived luteal tissues was also determined at d 1 to 5, 6 to 13 and 14 to 20 of cyclic cows, and d-60 and -90 of pregnant cows (n = 5 each). Progesterone level in d-60 CL was not different from those in d 6 to 13 CL and d-90 CL, although the difference between d 6 to 13 and d-90 was significant. In Experiment 2, protein expression pattern in CL at d-90 (n = 4) was compared with that in CL of cyclic cows at d 6 to 13 (n = 5). Significant changes in the level of protein expression were detected in 32 protein spots by two-dimensional polyacrylamide gel electrophoresis (2-DE), and 23 of them were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Six proteins were found only in pregnant CL, while the other 17 proteins were found only in cyclic CL. Among the above 6 proteins, vimentin which is involved in the regulation of post-implantation development was included. Thus, the protein expression pattern in CL was disorientated from cyclic luteal phase to mid pregnancy, and alterations in specific CL protein expression may contribute to the maintenance of pregnancy in Korean native cows.

Repeated cocaine weakens GABA(B)-Girk signaling in layer 5/6 pyramidal neurons in the prelimbic cortex

Repeated cocaine exposure triggers adaptations in layer 5/6 glutamatergic neurons in the medial prefrontal cortex (mPFC) that promote behavioral sensitization and drug-seeking behavior. While suppression of metabotropic inhibitory signaling has been implicated in these behaviors, underlying mechanisms are unknown. Here, we show that Girk/K(IR)3 channels mediate most of the GABA(B) receptor (GABA(B)R)-dependent inhibition of layer 5/6 pyramidal neurons in the mPFC and that repeated cocaine suppresses this pathway. This adaptation was selective for GABA(B)R-dependent Girk signaling in layer 5/6 pyramidal neurons of the prelimbic cortex (PrLC) and involved a D₁/₅ dopamine receptor- and phosphorylation-dependent internalization of GABA(B)R and Girk channels. Persistent suppression of Girk signaling in layer 5/6 of the dorsal mPFC enhanced cocaine-induced locomotor activity and occluded behavioral sensitization. Thus, the cocaine-induced suppression of GABA(B)R-Girk signaling in layer 5/6 pyramidal neurons of the prelimbic cortex appears to represent an early adaptation critical for promoting addiction-related behavior.

Codon-optimized expression of fish iridovirus capsid protein in yeast and its application as an oral vaccine candidate

Fish iridovirus causes systemic disease with high morbidity and mortality in various species of wild and farm-raised fish, resulting in severe economic losses. Recently, frequent outbreaks of iridovirus infection have occurred among cultured fish in many Asian countries, emphasizing the need for a protective vaccine programme or the development of a suitable therapy. In this study, we expressed a recombinant major capsid protein (rMCP) of rock bream iridovirus (RBIV) from yeast using codon optimization. The rMCP in yeast was added to feed in an attempt to induce intestinal mucosal immunity for protection against and/or to reduce the severity of fish iridovirus infection. We found that fish immunized orally with rMCP underwent a successful induction of antibodies (P < 0.05) and were protected (P = 0.0001) against viral challenge. Based upon these results, oral administration of immunogenic protein as an antigen can be considered a useful method for implementation of vaccine programmes against iridovirus as well as other marine viral diseases.

Antinociceptive curcuminoid, KMS4034, effects on inflammatory and neuropathic pain likely via modulating TRPV1 in mice

BACKGROUND

Curcumin, the active ingredient of turmeric (Curcuma longa), has a wide range of beneficial effects including anti-inflammation and analgesia. However, poor bioavailability of curcumin hinders its clinical application. To overcome this limitation, we modified the structure of curcumin and synthesized new derivatives with favourable pharmacokinetic profiles. Recently, curcumin has been shown to have an antagonizing effect on transient receptor potential vanilloid type 1 (TRPV1) ion channels. We investigated the antinociceptive activity of KMS4034 which had the most favourable pharmacokinetics among the tested curcumin derivatives.

METHODS

To evaluate the mechanism of the antinociceptive effects of KMS4034, capsaicin (I(CAP))- and heat (I(heat))-induced currents in TRPV1 expressing HEK293 cells were observed after the application of KMS4034. Nociceptive behavioural measurement using the hot-plate test, formalin test, and chronic constriction injury (CCI) model were evaluated in mice. Also, calcitonin gene-related peptide (CGRP) was stained immunohistochemically in the L4/5 dorsal horns in mice with neuropathic pain.

RESULTS

I(CAP) (P<0.01) and I(heat) (P<0.05) of TRPV1 were significantly blocked by 10 μM KMS4034. Behaviourally, noticeable antinociceptive effects after 10 mg kg(-1) of KMS4034 treatment were observed in the first (P<0.05) and second phases (P<0.05) of the formalin and hot-plate tests. The mechanical threshold of CCI mice treated with 10 mg kg(-1) KMS4034 was significantly increased compared with control. Immunohistochemical CGRP expression was decreased in the lamina I-II of the lumbar dorsal horns in KMS4034-treated CCI mice compared with the control (P<0.05).

CONCLUSIONS

KMS4034 may be an effective analgesic for various pain conditions.

Lipopolysaccharide-induced indoleamine 2,3-dioxygenase expression in the periodontal ligament

BACKGROUND AND OBJECTIVE

Indoleamine 2,3-dioxygenase (IDO) is a tryptophan-oxidizing enzyme with immune-inhibitory effects. The aim of this study was to investigate the expression of IDO by lipopolysaccharide (LPS), a component of gram-negative bacteria, in human periodontal ligament (PDL) cells.

MATERIAL AND METHODS

Human PDL cells and gingival fibroblasts (GFs) were prepared from explants of human PDLs and from gingival tissues of clinically healthy donors, respectively. Real-time RT-PCR, western blotting and the IDO enzyme assay were performed to determine the expression of IDO following LPS treatment of cells. LPS was injected into mice tail veins to evaluate the effects of LPS in vivo in the maxillary first molar. Immunofluorescence staining and histological analysis were followed to localize IDO in mouse PDL.

RESULTS

The level of expression of IDO mRNA in primary human PDL cells after LPS treatment was increased in a dose-dependent manner, reaching a peak 8 h after LPS treatment. The expression and activities of IDO protein were significantly increased in comparison with those of the control. In addition, the increased production of kynurenine in culture medium was observed 72 h after LPS treatment. In the immunofluorescence findings, stronger immunoreactivities were shown in PDL than in gingival tissues in the maxillae. In accordance with the immunofluorescence findings, LPS treatment induced a strong up-regulation of IDO mRNA in human PDL cells, whereas human GFs showed only a weak response to LPS.

CONCLUSION

These results clearly show that IDO was induced by LPS in primary human PDL cells, suggesting that PDL might be involved in the regulation of oral inflammatory disease.

[Clinical Usefulness of Antimicrobial Susceptibility Test for Helicobacter pylori.]

BACKGROUND

Antimicrobial resistance of Helicobacter pylori is considered as the main cause of failure of eradication therapy. Because resistance to metronidazole has been reported in 25.8% to 66.2% of H. pylori, a combination of proton pump inhibitors (PPI), amoxicillin, and clarithromycin is currently recommended as a primary therapy. We investigated the prevalence of antimicrobial resistance to the primary drugs and the impact of antimicrobial resistance on eradication rates.

METHODS

Between May and August 2005, H. pylori isolates from 93 patients were tested for antimicrobial susceptibility at Asan Medical Center. Susceptibility tests of clarithromycin and amoxicillin were performed by the disk diffusion method and those of metronidazole and tetracycline by Etest (AB Biodisk, Solna, Sweden). The medical records of the patients were reviewed to collect the data such as demographic findings, previous and current eradication therapies, and bacteriological outcome. The appropriate therapy was defined as three-drug-combination including susceptible drugs only, or four-drug-combination including metronidazole in the case of metronidazole-resistance.

RESULTS

Resistance rates to clarithromycin and metronidazole were 17.2% and 33.3%, respectively, but there was no resistance to tetracycline and amoxicillin. The eradication was successful in 32 of the 36 patients (88.9%) who received the appropriate therapy, but none of 4 patients who received an inappropriate therapy (P<0.01).

CONCLUSIONS

Resistance to clarithromycin seemed to increase and contribute to the failure of eradication therapy. For the appropriate therapy of H. pylori infection, the susceptibility results should be reported before initiation of the eradication therapy.

Clinical characteristics of children with rett syndrome

Objective

To identify the clinical characteristics and investigate function related aspects of Korean children with Rett syndrome.

Method

A total of 26 patients diagnosed as Rett syndrome were clinically observed until the age of five or over. We surveyed past history, developmental history, and presence of typical clinical features of Rett syndrome. Furthermore, we investigated differences in clinical characteristics according to functional status and changes in clinical features related to growth.

Results

There were no problems related to gestational, perinatal or neonatal history. Only 12 patients had an ultimate head circumference of less than 3 percentile. Developmental regression was definite in all patients. At final assessment, only 14 patients were able to walk. Twenty patients had an epileptic history requiring medication. Sixteen patients with scoliosis showed progression during serial follow-up. The percentage of patients who were able to walk before 16 months was higher in the high function group than the low function group. The age of regression was 5.4 and 4.0 years in the high and low function group respectively, but the difference was not statistically significant. Scoliosis was more severe and seizure onset age was younger in the low function group.

Conclusion

We investigated 26 clinical characteristics in Korean children with Rett syndrome. Their clinical features change according to age, and we believe such knowledge could be utilized in rehabilitation to minimize their disabilities.

Neurodevelopmental disorders of children screened by the infantile health promotion system

OBJECTIVE

To perform an in depth evaluation of children, and thus provide a systematic method of managing children, who after infantile health screening, were categorized as suspected developmental delay.

METHOD

78 children referred to the Developmental Delay Clinic of Ilsan Hospital after suspected development delay on infantile health examinations were enrolled. A team comprised of a physiatrist, pediatrician and pediatric psychiatrist examined the patients. Neurological examination, speech and cognitive evaluation were done. Hearing tests and chromosome studies were performed when needed clinically. All referred children completed K-ASQ questionnaires. Final diagnoses were categorized into specific language impairment (SLI), global developmental delay (GDD), intellectual disability (ID), cerebral palsy (CP), motor developmental delay (MD) or autism spectrum disorder (ASD).

RESULTS

72 of the 78 patients were abnormal in the final diagnosis, with a positive predictive value of 92.3%. Thirty (38.4%) of the 78 subjects were diagnosed as GDD, 28 (35.8%) as SLI, 5 (6.4%) as ASD, 9 (12.5%) as MD, and 6 (7.6%) as normal. Forty five of the 78 patients had risk factors related to development, and 18 had a positive family history for developmental delay and/or autistic disorders. The mean number of abnormal domains on the K-ASQ questionnaires were 3.6 for ASD, 2.7 for GDD, 1.8 for SLI and 0.6 for MD. Differences between these numbers were statistically significant (p<0.05).

CONCLUSION

Because of the high predictive value of the K-ASQ, a detailed evaluation is necessary for children suspected of developmental delay in an infantile health promotion system.

Characteristics of late-onset epilepsy and EEG findings in children with autism spectrum disorders

Purpose

To investigate the clinical characteristics of late-onset epilepsy combined with autism spectrum disorder (ASD), and the relationship between certain types of electroencephalography (EEG) abnormalities in ASD and associated neuropsychological problems.

Methods

Thirty patients diagnosed with ASD in early childhood and later developed clinical seizures were reviewed retrospectively. First, the clinical characteristics, language and behavioral regression, and EEG findings of these late-onset epilepsy patients with ASD were investigated. The patients were then classified into 2 groups according to the severity of the EEG abnormalities in the background rhythm and paroxysmal discharges. In the severe group, EEG showed persistent asymmetry, slow and disorganized background rhythms, and continuous sharp and slow waves during slow sleep (CSWS).

Results

Between the two groups, there was no statistically significant difference in mean age (P=0.259), age of epilepsy diagnosis (P=0.237), associated family history (P=0.074), and positive abnormal magnetic resonance image (MRI) findings (P=0.084). The severe EEG group tended to have more neuropsychological problems (P=0.074). The severe group statistically showed more electrographic seizures in EEG (P=0.000). Rett syndrome was correlated with more severe EEG abnormalities (P=0.002). Although formal cognitive function tests were not performed, the parents reported an improvement in neuropsychological function on the follow up checkup according to a parent's questionnaire.

Conclusion

Although some ASD patients with late-onset epilepsy showed severe EEG abnormalities, including CSWS, they generally showed an improvement in EEG and clinical symptoms in the long-term follow up. In addition, severe EEG abnormalities tended to be related to the neuropsychological function.

Establishment of a reference interval for natural killer cell activity through flow cytometry and its clinical application in the diagnosis of hemophagocytic lymphohistiocytosis

Recently, the Histiocyte Society revised the diagnostic criteria for hemophagocytic lymphohistiocytosis (HLH) to include low or absent natural killer (NK) cell activity, according to local laboratory reference. The aim of this study was to establish reference interval for functional NK-cell activity in 63 healthy Korean individuals using a flow-cytometric assay. We used peripheral blood mononuclear cells (PBMCs) as effector cells and Fluorescein isothiocyanate-labeled K562 cells as target cells. NK-cell activity was calculated using the following equation: NK-cell activity (%) = (test lysis - spontaneous lysis) x 100/(maximum lysis - spontaneous lysis). NK-cell activity was analyzed in 13 known HLH patients and 16 suspected non-HLH patients using a flow-cytometric assay. The mean (+/-SD) cytotoxicity of PBMCs from healthy individuals was 20.9 +/- 5.3% and the reference interval was 11.8-31.9%. The mean NK-cell activity of HLH patients (8.3 +/- 8.9%) was significantly lower (P = 0.001) than that of non-HLH patients (20.1 +/- 7.8%). The sequential changes in NK-cell activity in the HLH group corresponded to clinical and laboratory findings following treatment. We successfully developed a functional NK-cell activity test for use in the clinical laboratory and obtained a reference interval of NK-cell activity from healthy donors. This assay, and associated reference interval, was used to analyze 30 clinically relevant specimens and the results were shown to be well correlated.

A case of lineage switch from acute lymphoblastic leukemia to acute myeloid leukemia

Lineage switch from acute lymphoblastic leukemia (ALL) to acute myeloid leukemia (AML) is very rare. We report a case of a 9 yr-old ALL patient relapsed as acute myelomonocytic leukemia. At the initial diagnosis, the blast cell morphology and immunophenotype were consistent with the diagnosis of typical ALL (L1 subtype according to FAB classification). The BCR-ABL fusion gene was not found by reverse transcription-PCR. Complete remission (CR) was achieved after induction and consolidation chemotherapy (Children's Cancer Study Group 1891 protocol, CCG1891). Nine months, which is a very short time compared with other cases in the literatures, after the diagnosis of ALL, she relapsed with completely different blasts (typical AML, M4 according to FAB classification) in morphology, cytochemistry, and immunophenotyping. The karyotype has changed from 56,XY,+X,+Y,+Y,+4,+8,+10, +14,+17,-20,+21,+21,+21[6]/57,idem,+Y[19] to 46,XY,t(8;16)(p11.2;p13.1)[19]/46,XY[1], showing unrelated chromosomal abnormality to the karyotype at the initial diagnosis. Moreover, both findings were quite specific for each common cell ALL and acute myelomonocytic leukemia. These findings support that this case is completely different leukemic clones occurred at each leukemic expression. The treatment with AML 2000 protocol chemotherapy failed, and he underwent the chemotherapy with the combination of high dose cytarabine and mitoxantrone and has been in CR state for 21 months, until now.