Focal cortical dysplasia II caused by brain somatic mutation of IRS-1 is associated with ERK signaling pathway activation.

Somatic mutations have been identified in 10% to 63% of focal cortical dysplasia type II samples, primarily linked to the mTOR pathway. When the causative genetic mutations are not identified, this opens the possibility of discovering new pathogenic genes or pathways that could be contributing to the condition. In our previous study, we identified a novel candidate pathogenic somatic variant of IRS-1 c.1791dupG in the brain tissue of a child with focal cortical dysplasia type II. This study further explored the variant's role in causing type II focal cortical dysplasia through in vitro overexpression in 293T and SH-SY5Y cells and in vivo evaluation via in utero electroporation in fetal brains, assessing effects on neuronal migration, morphology, and network integrity. It was found that the mutant IRS-1 variant led to hyperactivity of p-ERK, increased cell volume, and was predominantly associated with the MAPK signaling pathway. In vivo, the IRS-1 c.1791dupG variant induced abnormal neuron migration, cytomegaly, and network hyperexcitability. Notably, the ERK inhibitor GDC-0994, rather than the mTOR inhibitor rapamycin, effectively rescued the neuronal defects. This study directly highlighted the ERK signaling pathway's role in the pathogenesis of focal cortical dysplasia II and provided a new therapeutic target for cases of focal cortical dysplasia II that are not treatable by rapamycin analogs.

[Different concentrations of adapalene induce differentiation and apoptosis of SH-SY5Y cells]. / 不同浓度阿达帕林诱导SH-SY5Y细胞的分化及凋亡.

OBJECTIVES: To investigate the effects of different concentrations of adapalene on the morphology and functions of neuroblastoma cell line SH-SY5Y, as well as its role in inducing cell differentiation and apoptosis. METHODS: SH-SY5Y cells were divided into control group, low concentration (0.1 µM and 1 µM) adapalene groups, and high concentration (10 µM) adapalene group. Time-lapse microscopy was used to observe the morphological changes of SH-SY5Y cells. Immunofluorescence staining was performed to detect the expression of neuronal specific marker ßIII-tubulin and mature neuronal marker neurofilament heavy polypeptide (NFH). Multi-electrode array was used to record the electrophysiological features of SH-SY5Y cells. Cell apoptosis was evaluated using a cell apoptosis detection kit. RESULTS: Low concentrations of adapalene promoted the formation of neurite outgrowth in SH-SY5Y cells, with the neurites interconnected to form a network. Spontaneous discharge activity was observed in SH-SY5Y cells treated with low concentrations of adapalene. Compared to the control group, the expression of ßIII-tubulin and NFH increased in the 1 µM adapalene group, while the level of cell apoptosis increased in the high concentration adapalene group (P<0.05). CONCLUSIONS: Low concentrations of adapalene can induce differentiation of SH-SY5Y cells into mature functional neurons, while high concentrations of adapalene can induce apoptosis in SH-SY5Y cells.

Astrocytes in Migration.

Cell migration is a fundamental phenomenon that underlies tissue morphogenesis, wound healing, immune response, and cancer metastasis. Great progresses have been made in research methodologies, with cell migration identified as a highly orchestrated process. Brain is considered the most complex organ in the human body, containing many types of neural cells with astrocytes playing crucial roles in monitoring normal functions of the central nervous system. Astrocytes are mostly quiescent under normal physiological conditions in the adult brain but become migratory after injury. Under most known pathological conditions in the brain, spinal cord and retina, astrocytes are activated and become hypertrophic, hyperplastic, and up-regulating GFAP based on the grades of severity. These three observations are the hallmark in glia scar formation-astrogliosis. The reactivation process is initiated with structural changes involving cell process migration and ended with cell migration. Detailed mechanisms in astrocyte migration have not been studied extensively and remain largely unknown. Here, we therefore attempt to review the mechanisms in migration of astrocytes.

[Surgery for pediatric intractable epilepsy due to posterior quadrantic cortical dysplasia].

OBJECTIVE: To investigate the clinical features and surgical strategy for pediatric intractable epilepsy due to posterior quadrantic cortical dysplasia and to assess the surgical outcomes. METHODS: The clinical features and preoperative evaluation results of 14 children with intractable epilepsy due to posterior quadrantic cortical dysplasia were retrospectively analyzed. The localization values of video-electroencephalography and intraoperative monitoring and the indications, advantages and disadvantages of temporoparietooccipital disconnection were evaluated. RESULTS: The 14 children had different seizure types, of which spasm was the most common one. The lesions of cortical dysplasia involved the central cerebral region in 2 cases. After temporoparietooccipital disconnection in 14 patients, 13 cases were seizure-free; only one case still had seizures, but the frequency dropped by more than 50%. CONCLUSIONS: Temporoparietooccipital disconnection is a safe and effective surgical procedure for children with intractable epilepsy due to posterior quadrantic cortical dysplasia.

[Value of muscle enzyme analysis in differential diagnosis of childhood myopathic hyper-creatine kinase-emia].

OBJECTIVE: To summarize the etiology and clinical characteristics of children with myopathic elevated creatine kinase (CK) levels. The degrees of elevated CK as well as lactic dehydrogenase (LDH) and aspartate aminotransferase (AST) levels in different myopathy were analyzed. METHODS: The clinical data of 235 cases characterized as myopathic hyper-CK-emia from January 2004 to December 2011 were collected and analyzed. A retrospective analysis of LDH and AST levels according to CK in part of the patients were reviewed. RESULTS: Of the 235 cases, 180 were male and 55 female. According to the age at which hyper-CK-emia was diagnosed, 64 cases were under 6 months, 90 between 6 months and 3 years, 50 between 3 and 6 years and 31 between 6 and 14 years. Their CK levels significantly increased in 162 cases, moderately increased in 31 cases, and slightly increased in 42 cases. The age at which hyper-CK-emia was diagnosed and the CK level had no correlation with muscle weakness and the severity. As to CK levels: Duchenne muscular dystrophy (DMD) > inflammatory myopathies > congenital muscular dystrophy (CMD) > metabolic myopathies. LDH and AST levels: DMD > inflammatory myopathies > metabolic myopathies > CMD. CONCLUSION: Unlike adults, the etiology of myopathic hyper-CK-emia in children is complicated and diverse. The onset type, the degree and duration of hyper-CK-emia are helpful to make the diagnosis. CK increases most significantly in DMD, then in inflammatory myopathies, CMD, and metabolic myopathies. Diagnostic flowchart of myogenic hyper-CK-emia should follow a certain process, and the indications of biochemical tests, metabolic screening, electrophysiological examination, muscle biopsy and genetic testing should be made. Finally, different treatments should be designed according to the etiology.

[Clinical presentations of pediatric anti-N-methyl-D-aspartate receptor encephalitis].

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is one of the most common autoimmune encephalitis in children with characterized clinical features. Here we review clinical presentations of typical and atypical anti-NMDAR encephalitis and characteristics of clinical presentations of pediatric anti-NMDAR encephalitis.

Recent advances and current status of gene therapy for epilepsy.

BACKGROUND: Epilepsy is a common neurological disorder with complex pathogenic mechanisms, and refractory epilepsy often lacks effective treatments. Gene therapy is a promising therapeutic option, with various preclinical experiments achieving positive results, some of which have progressed to clinical studies. DATA SOURCES: This narrative review was conducted by searching for papers published in PubMed/MEDLINE with the following single and/or combination keywords: epilepsy, children, neurodevelopmental disorders, genetics, gene therapy, vectors, transgenes, receptors, ion channels, micro RNAs (miRNAs), clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas)9 (CRISPR/Cas9), expression regulation, optogenetics, chemical genetics, mitochondrial epilepsy, challenges, ethics, and disease models. RESULTS: Currently, gene therapy research in epilepsy primarily focuses on symptoms attenuation mediated by viral vectors such as adeno-associated virus and other types. Advances in gene therapy technologies, such as CRISPR/Cas9, have provided a new direction for epilepsy treatment. However, the clinical application still faces several challenges, including issues related to vectors, models, expression controllability, and ethical considerations. CONCLUSIONS: Here, we summarize the relevant research and clinical advances in gene therapy for epilepsy and outline the challenges facing its clinical application. In addition to the shortcomings inherent in gene therapy components, the reconfiguration of excitatory and inhibitory properties in epilepsy treatment is a delicate process. On-demand, cell-autonomous treatments and multidisciplinary collaborations may be crucial in addressing these issues. Understanding gene therapy for epilepsy will help clinicians gain a clearer perception of the research progress and challenges, guiding the design of future clinical protocols and research decisions.

PACS gene family-related neurological diseases: limited genotypes and diverse phenotypes.

BACKGROUND: The PACS gene family has been demonstrated to be related to intracellular vesicular trafficking. The phenotypic manifestations caused by the pathogenic variants of PACS include epilepsy, intellectual disability/developmental delay, and malformations, such as facial abnormalities. METHODS: We identified seven new cases with pathogenic or likely pathogenic PACS variants using next-generation sequencing. Detailed information obtained from these patients was analyzed along with that obtained from previously reported patients. RESULTS: With the inclusion of the newly diagnosed cases in this study, 103 cases with PACS gene family-related neurological diseases were reported, of which 43 were PACS2-related cases and the remaining were PACS1-related cases. Most patients had seizures, which have been reported to be effectively controlled by several types of anti-seizure medications (ASMs). The most efficacious and frequently prescribed ASMs included sodium valproate (43.3%, 13/30), oxcarbazepine/carbamazepine (26.7%, 8/30), and levetiracetam (20%, 6/30). Almost all patients had intellectual disability/developmental delay. The most common pathogenic missense variants were PACS1 p. Arg203Trp and PACS2 p.Glu209Lys. In addition, we report a patient carrying a likely pathogenic copy number variation (CNV) (de novo heterozygous deletion of chr14:105821380-106107443, 286 kilobase, destroyed part of the furin-binding region domain and the protein structure after it) with more severe and refractory late-onset epilepsy. CONCLUSIONS: The clinical phenotypes of the different PACS heterozygous missense variants were similar. The pathogenic variant sites of PACS1 and PACS2 were quite limited but located in different regions. A CNV destroying part of the PACS2 gene might also be pathogenic. These findings may provide an important clue for further functional studies on the pathogenic mechanism of neurological disorders related to the PACS gene family. Video Abstract (MP4 65767 kb).

Traumatic scratch injury in astrocytes triggers calcium influx to activate the JNK/c-Jun/AP-1 pathway and switch on GFAP expression.

Astrocyte activation is a hallmark of central nervous system injuries resulting in glial scar formation (astrogliosis). The activation of astrocytes involves metabolic and morphological changes with complex underlying mechanisms, which should be defined to provide targets for astrogliosis intervention. Astrogliosis is usually accompanied by an upregulation of glial fibrillary acidic protein (GFAP). Using an in vitro scratch injury model, we scratched primary cultures of cerebral cortical astrocytes and observed an influx of calcium in the form of waves spreading away from the wound through gap junctions. Using the calcium blocker BAPTA-AM and the JNK inhibitor SP600125, we demonstrated that the calcium wave triggered the activation of JNK, which then phosphorylated the transcription factor c-Jun to facilitate the binding of AP-1 to the GFAP gene promoter to switch on GFAP upregulation. Blocking calcium mobilization with BAPTA-AM in an in vivo stab wound model reduced GFAP expression and glial scar formation, showing that the calcium signal, and the subsequent regulation of downstream signaling molecules, plays an essential role in brain injury response. Our findings demonstrated that traumatic scratch injury to astrocytes triggered a calcium influx from the extracellular compartment and activated the JNK/c-Jun/AP-1 pathway to switch on GFAP expression, identifying a previously unreported signaling cascade that is important in astrogliosis and the physiological response following brain injury.

[Advance in genetic study for idiopathic generalized epilepsy].

Epilepsy is a kind of common neurological diseases in the world. Over 50% of epilepsies have genetic basis. We define "idiopathic epilepsy" as a kind of epilepsy or epilepsy syndrome only with genetic factors, and idiopathic generalized epilepsies (IGEs) is a major type of idiopathic epilepsies. Susceptibility genes of epilepsies are mainly ion channel genes. Both gene mutation and copy number variation lead to epilepsies. Childhood absence epilepsy (CAE) is a crucial part of IGEs. Due to the consistency of CAE's phenotype and results of EEG, studies related to CAE susceptibility genes tend to be easier to conduct. Through these studies about IGEs /CAE susceptibility genes, we can determine pathogenic model of epilepsy genetics, and find the way to diagnose accurately in molecular genetics, to identify types of epilepsies, to detect targets of antiepileptic drugs, and provide a basis for gene therapy.

[Epidemiological study on developmental delay of 18-month-old children from four districts/counties in Beijing].

OBJECTIVE: To investigate epidemiological characteristics of prevalence, impact factors and etiology on developmental delay of 18-month-old children from four districts/counties in Beijing. METHODS: An epidemiological study on developmental delay was designed to investigate all the 18-month-old children enrolled from Shunyi,Daxing,Miyun and Yanqing districts/counties in Beijing from May to September, 2011. Combining the tertiary network of child health with hospital clinical study was used. Child developmental questionnaires were completed by doctors in communities of the first network of child health. Gesell Developmental Schedules for children with Denver developmental screening test (DDST) screening positive results were assessed by doctors in districts/counties hospitals of the second network of child health. The children diagnosed as developmental delay were transferred to the tertiary hospitals of the third network of child health for further etiological diagnosis, follow-up and developmental evaluation. The case-control study compared between children with/without developmental delay were performed in accordance with the 1:4 ratios by gender and residence community matched. SPSS 16.0 was adopted for data analysis of the case-control study. RESULTS: A total of 3 182 children were screened among the 4 037 children fitting the criteria,and the coverage rate was 78.8% (3 182/4 037). Of the 3 182 screened children, 22 children were diagnosed as developmental delay. The prevalence rate was 6.91 ‰ (22/3 182). Out of the 22 children with developmental delay, 15 were boys and 7 were girls. The sex ratio was 2.1:1. The prevalence rates of the children with developmental delay in Shunyi, Daxing, Miyun and Yanqing were 3.45 ‰ (4/1 160), 4.50 ‰(5/1 111), 15.87 ‰(7/441) and 12.77 ‰ (6/479), respectively. The results from one-way ANOVA analysis showed the main risk factors in children with developmental delay included low-income families, mothers' low educational level, small size for gestational age infant, multiple fetuses, serious diseases after birth, congenital malformations and physical retardation (P<0.05). CONCLUSION: The screening coverage rate of this study is 78.8%. The prevalence rate of children with developmental delay is 6.91 ‰, which is significantly different in sex ratio and districts of the subjects. The etiology of developmental delay might be associated with social-economic and biological factors.

[Genetic and phenotypic characteristics of SCN1A mutations in Dravet syndrome].

OBJECTIVE: To study SCN1A gene mutations and their inheritance in patients with Dravet syndrome(DS), and to analyze the phenotypes of their family members and genotype-phenotype correlations. METHODS: Genomic DNA was extracted from peripheral blood samples from 181 DS patients and their parents. Phenotypes of affected members were analyzed. SCN1A gene mutations were screened using PCR-DNA sequencing and multiplex ligation-dependent probe amplification (MLPA) RESULTS: SCN1A gene mutations were identified in 128 patients (70.7%), which included 60 missense mutations (46.9%), 55 truncation mutations (43.0%), 10 splice site mutations (7.8%), and 3 cases with SCN1A gene fragment deletions or duplications(2.3%). Five patients (3.9%) had mutations inherited from one of their parents. One father has carried a somatic mutation mosaicism (C373fsx378). For the 5 parents carrying a mutation, 1 had febrile seizures, 2 had febrile seizures plus, 1 had afebrile generalized tonic-clonic seizures, whilst 1 was normal. CONCLUSION: The mutation rate of SCN1A in DS patients is about 70%. Most mutations are of missense and truncation mutations. Only a few patients have carried fragment deletions or duplications. Most SCN1A mutations are de novo, only a few were inherited from the parents. SCN1A mutations carried by the parents can be in the form of mosaicism. The phenotypes of parents with SCN1A mutations are either mild or normal.

[Co-morbidity of attention deficit hyperactivity disorder in children with epilepsy].

OBJECTIVE: To estimate the prevalence of attention deficit hyperactivity disorder (ADHD) in children with epilepsy, and the factors that may contribute to the prevalence of co-morbidity between ADHD and epilepsy. METHODS: A total of 256 children aged 6-15 years old who were diagnosed with epilepsy were enrolled. The prevalence of ADHD in children with epilepsy, and the factors that may contribute to the development of co-morbidity between ADHD and epilepsy were explored. RESULTS: The systematic evaluation in 192 patients was completed. Of the 192 children, 81 (42.2%) were diagnosed with ADHD. The earlier the epilepsy onset, the higher the frequency of the co-morbidity of ADHD occurring. The longer the period of antiepileptic medication, the higher the prevalence of the co-morbidity of ADHD. Epileptic children receiving a combination of antiepileptic drugs had a higher prevalence of ADHD. ADHD was more common in children with some specific types of epilepsy, such as Lannox-Gastaut syndrome and generalized tonic-clonic epilepsy, or epilepsy with multifocal epileptic discharges in the EEG record. CONCLUSIONS: ADHD occurs frequently in children with epilepsy. The factors associated with increased risk of ADHD include the onset age of epilepsy, the types of seizures or epileptic syndromes, the epileptiform EEG discharges, and the effects of antiepileptic drugs.

[Clinical characteristics and follow-up management of 135 children with myasthenia gravis].

OBJECTIVE: To investigate and analyze the clinical manifestations, classification, therapeutic approaches and follow-up of myasthenia gravis (MG) in children in order to improve its management and prognosis. METHODS: Clinical information of 135 children with MG, who were diagnosed between January 1993 to January 2008, were collected and retrospectively analyzed. And prospective following-up of these patients were conducted. RESULTS: Among the 135 cases, 59 were males and 76 females, giving the ratio of M/F around 1:1.3. Totally, 115 cases (85.2%) were type I MG (ocular type), of which only 4.2% developed to generalized type during the subsequent clinical course. Type II MG (generalized type)was found in 18 cases (13.4%) and type III MG in two cases(1.5%). The onset age ranged from 5 month to 15 years, with 50.3% before three years and 80.7% before seven years. Upper respiratory tract infection was presented in 26.7% (36/135) of the sick children before the onset of MG. Among the 106 children being followed up, recurrence of the disease identified in 50.9% and the number of relapse ranged from 1 to 9. Altogether, 40.19% (43/106) of the cases were positive for anti-acetylcholine receptor antibodies (AchR-Ab) on the initial examination, and the AchR-Ab postitive rate showed no difference among different clinical subtypes and states. However, during the follow-up, 53% (9/17) of the recurrent cases, who were negative at the first onset, turned to be positive, and 37.97% (30/79) were positive for repetitive nerve stimulation in electromyogram test. There were 71 % (45/63) of all the cases showed reduced levels of CD4+ and/or CD3+ and/or CD8+. Thymus proliferation was found in 5.93% (8/135) through CT scan and thymoma in 1.48% (2/135). Steroids and anti-cholinesterase administration were effective in most cases with good prognosis. CONCLUSION: Childhood MG, mainly type I, is relatively common in China, with specific characteristics which are different from western patients or adult MG in morbidity, sex distribution, progress, laboratory examination and treatment. The prevalence of myasthenia gravis crisis and mortality rate in MG children is low, and few are accompanied with thymoma. Most MG cases have a satisfied prognosis and few have neuropsychic sequela.

[Leucodystrophy induced by late onset 3-hydroxy-3-methylglutaric aciduria].

3-Hydroxy-3-methylglutaric aciduria is a rare disorder of organic acid metabolism caused by 3-hydroxy-3-methylglutaryl-coenzyme A lyase deficiency. The disorder was common in neonatal or infant period. Here a case of late onset 3-hydroxy-3-methylglutaric aciduria complicated by leucodystrophy was reported. The patient was a 7-year-old boy. He presented with progressive headache, drowsiness and vomiting. Hepatic lesions, ketosis and leucopenia were found. Symmetrical diffused leucodystrophy was shown by MRI. Blood levels of isovalerylcarnitine and acetylcarnitine increased significantly. Urinary levels of 3-hydroxy-3-methylglutaric, 3-methylglutaconic, 3-hydroxyglutaric acids and 3-methyl-crotonylglycine increased significantly. Symptoms were released by intravenous infusion of L-carnitine and glucose. After treatment for 6 months, urinary levels of 3-hydroxy-3-methylglutaric aciduria decreased in the boy and his health improved.

[Leigh syndrome due to mitochondrial respiratory chain complex II deficiency].

Mitochondrial respiratory chain complex II deficiency is a rare documented cause of mitochondrial diseases. This study reported a case of Leigh syndrome due to isolated complex II deficiency. A boy presented with progressive weakness, motor regression and dysphagia after fever from the age of 8 months and hospitalized at the age of 10 months. Elevated blood levels of lactate and pyruvate were observed. Brain magnetic resonance image showed symmetrical lesions in the basal ganglia. Mitochondrial respiratory chain complex I-V activities in peripheral leukocytes were measured using spectrophotometric assay. Mitochondrial gene screening of common point mutations was performed. The complex II activity in the peripheral leukocytes decreased to 21.9 nmol/min per mg mitochondrial protein (control: 47.3±5.3 nmol/min per mg mitochondrial protein). The ratio of complex II activity to citrate synthase activity (22.1%) also decreased (control: 50.9%±10.7 %). No point mutation was found in mitochondrial DNA. The boy was diagnosed as Leigh syndrome due to isolated complex II deficiency. Psychomotor improvements were observed after the treatment. The patient is 22 months old and in a stable condition.

Four-year-old anti-N-methyl-D-aspartate receptor encephalitis patient with ovarian teratoma: A case report.

BACKGROUND: A population-based comparative study in United States shows that the prevalence and incidence of autoimmune encephalitis are comparable to those of infectious encephalitis and its detection is increasing over time. Some patients are complicated with ovarian teratoma. The younger the patient is, the less likely a tumor will be present. CASE SUMMARY: This case report describes the successful treatment of anti-N-methyl-D-aspartate-receptor (NMDAR) encephalitis by early laparoscopic ovarian cystectomy and immunotherapy in a 4-year-old female child. And to the best of our knowledge, this detailed case report describes the youngest patient to date with anti-NMDAR encephalitis who underwent laparoscopic ovarian cystectomy. CONCLUSION: Although the younger the patient is, the less likely a tumor will be detected, we still emphasize that all patients with suspected or confirmed anti-NMDAR encephalitis should be screened for ovarian tumors if possible. Prompt initiation of immunotherapy and tumor removal are crucial for good outcomes.

[Genotype, phenotype analysis and follow-up study on patients with Duchenne/Becker muscular dystrophy].

OBJECTIVE: To improve the diagnosis and management of Duchenne/Becker muscular dystrophy(DMD/BMD). METHODS: Clinical features of 90 cases of DMD/BMD were collected. Genomic DNA was extracted using standard procedures from the peripheral blood leukocytes, and multiplex ligation-dependent probe amplification (MLPA) was applied to detect DMD gene to identify genetic mutation. For those patients whose deletion/duplication mutation was not identified, FKRP gene mutation analysis was performed using PCR-DNA direct sequence. All the cases were followed up. RESULTS: Among the 90 cases of clinically diagnosed DMD/BMD, exons deletion of DMD was detected in 58 cases (64.44%), and exons duplication in 9 (10.00%). Among the 34 mothers with an affected boy but without previous genetic conformation, 17 were confirmed to be carriers with gene deletion/duplication. None of the 23 cases, without detected DMD gene deletion/duplication, carried FKRP gene mutation. Fourteen children were given short-term intermittent prednisone therapy (0.75 mg/kg daily during the first 10 days of each month). The course was not long enough and the sample size was too small to conclude any benefits or side effects. Prenatal diagnosis was provided for one mother in her next pregnancy detecting a female carrier fetus. CONCLUSION: DMD gene deletions mainly occurs between exons 45 and 54, while duplications mostly at 5'-terminus. Identification of the characteristics and types of gene mutation may facilitate the recognition and prognosis prediction of DMD/BMD. MLPA is a non-complex and quick diagnostic tool for DMD/BMD and its carriers, and also helpful in genetic counseling.