Mutations in ACTL6B Cause Neurodevelopmental Deficits and Epilepsy and Lead to Loss of Dendrites in Human Neurons.

We identified individuals with variations in ACTL6B, a component of the chromatin remodeling machinery including the BAF complex. Ten individuals harbored bi-allelic mutations and presented with global developmental delay, epileptic encephalopathy, and spasticity, and ten individuals with de novo heterozygous mutations displayed intellectual disability, ambulation deficits, severe language impairment, hypotonia, Rett-like stereotypies, and minor facial dysmorphisms (wide mouth, diastema, bulbous nose). Nine of these ten unrelated individuals had the identical de novo c.1027G>A (p.Gly343Arg) mutation. Human-derived neurons were generated that recaptured ACTL6B expression patterns in development from progenitor cell to post-mitotic neuron, validating the use of this model. Engineered knock-out of ACTL6B in wild-type human neurons resulted in profound deficits in dendrite development, a result recapitulated in two individuals with different bi-allelic mutations, and reversed on clonal genetic repair or exogenous expression of ACTL6B. Whole-transcriptome analyses and whole-genomic profiling of the BAF complex in wild-type and bi-allelic mutant ACTL6B neural progenitor cells and neurons revealed increased genomic binding of the BAF complex in ACTL6B mutants, with corresponding transcriptional changes in several genes including TPPP and FSCN1, suggesting that altered regulation of some cytoskeletal genes contribute to altered dendrite development. Assessment of bi-alleic and heterozygous ACTL6B mutations on an ACTL6B knock-out human background demonstrated that bi-allelic mutations mimic engineered deletion deficits while heterozygous mutations do not, suggesting that the former are loss of function and the latter are gain of function. These results reveal a role for ACTL6B in neurodevelopment and implicate another component of chromatin remodeling machinery in brain disease.

A near-infrared brain function study of Chinese dyslexic children.

Recently, two findings using functional magnetic resonance imaging of dyslexic in Chinese show the left middle frontal gyrus is a crucial area associated with reading disability. The purpose of present study was to replicate the previous findings using near-infrared spectroscopy and a consonant-vowel task which engaged finer-grained phonological processing. Compared to the control group, our study showed the dyslexic children had decreased amounts of oxy-hemoglobin and total-hemoglobin in the left dorsolateral prefrontal cortex. These results supported the previous findings and indicated that phonological deficit was also the cause of dyslexia in Chinese and it might be explained by decreased activity in left dorsolateral prefrontal cortex. Our study suggests that dyslexic children have an abnormal hemodynamic pattern in the left inferior frontal gyrus and the left middle frontal gyrus, which can provide a new target for diagnosing or treating the condition with the near-infrared spectroscopy.

Working memory function in Chinese dyslexic children: a near-infrared spectroscopy study.

The deficiency theories of dyslexia are quite contradictory and the cross-cultural studies in recent years mainly focused on whether the dyslexics among cultures shared the same cognitive profile or just based on the language. This study used Near-Infrared Spectroscopy (NIRS) imaging to measure the regional cerebral blood volume (BV) and the changes of cerebral activation in the left prefrontal cortex of 12 Chinese dyslexic children and their 12 age-matched normal controls during the Paced Visual Serial Addition Test (PVSAT). Results showed that the scores of PVSAT of dyslexic children were significantly lower than those of the normal children (t=3.33, P<0.01). The activations of the left prefrontal cortex in the normal group were significantly greater than those of dyslexic children (all P<0.01). Our results indicated that Chinese dyslexia had a general deficiency in working memory and this may be caused by the abnormal metabolic activity of brain blood volume in the left prefrontal cortex and the deficits in brain function might be the basis of neuropathology of Chinese dyslexia. Present study supports the difference on brain activation of dyslexics from different languages may be caused by the same cognitive system related to reading.

FOXG1 dose tunes cell proliferation dynamics in human forebrain progenitor cells.

Heterozygous loss-of-function mutations in Forkhead box G1 (FOXG1), a uniquely brain-expressed gene, cause microcephaly, seizures, and severe intellectual disability, whereas increased FOXG1 expression is frequently observed in glioblastoma. To investigate the role of FOXG1 in forebrain cell proliferation, we modeled FOXG1 syndrome using cells from three clinically diagnosed cases with two sex-matched healthy parents and one unrelated sex-matched control. Cells with heterozygous FOXG1 loss showed significant reduction in cell proliferation, increased ratio of cells in G0/G1 stage of the cell cycle, and increased frequency of primary cilia. Engineered loss of FOXG1 recapitulated this effect, while isogenic repair of a patient mutation reverted output markers to wild type. An engineered inducible FOXG1 cell line derived from a FOXG1 syndrome case demonstrated that FOXG1 dose-dependently affects all cell proliferation outputs measured. These findings provide strong support for the critical importance of FOXG1 levels in controlling human brain cell growth in health and disease.

Inhibitory ability of children with developmental dyscalculia.

Inhibitory ability of children with developmental dyscalculia (DD) was investigated to explore the cognitive mechanism underlying DD. According to the definition of developmental dyscalculia, 19 children with DD-only and 10 children with DD&RD (DD combined with reading disability) were selected step by step, children in two control groups were matched with children in case groups by gender and age, and the match ratio was 1:1. Psychological testing software named DMDX was used to measure inhibitory ability of the subjects. The differences of reaction time in number Stroop tasks and differences of accuracy in incongruent condition of color-word Stroop tasks and object inhibition tasks between DD-only children and their controls reached significant levels (P<0.05), and the differences of reaction time in number Stroop tasks between dyscalculic and normal children did not disappear after controlling the non-executive components. The difference of accuracy in color-word incongruent tasks between children with DD&RD and normal children reached significant levels (P<0.05). Children with DD-only confronted with general inhibitory deficits, while children with DD&RD confronted with word inhibitory deficits only.

Regenerating Damaged Myocardium: A Review of Stem-Cell Therapies for Heart Failure.

Cardiovascular disease (CVD) is one of the contributing factors to more than one-third of human mortality and the leading cause of death worldwide. The death of cardiac myocyte is a fundamental pathological process in cardiac pathologies caused by various heart diseases, including myocardial infarction. Thus, strategies for replacing fibrotic tissue in the infarcted region with functional myocardium have long been a goal of cardiovascular research. This review begins by briefly discussing a variety of somatic stem- and progenitor-cell populations that were frequently studied in early investigations of regenerative myocardial therapy and then focuses primarily on pluripotent stem cells (PSCs), especially induced-pluripotent stem cells (iPSCs), which have emerged as perhaps the most promising source of cardiomyocytes for both therapeutic applications and drug testing. We also describe attempts to generate cardiomyocytes directly from cardiac fibroblasts (i.e., transdifferentiation), which, if successful, may enable the pool of endogenous cardiac fibroblasts to be used as an in-situ source of cardiomyocytes for myocardial repair.

Lesch-Nyhan disease causes impaired energy metabolism and reduced developmental potential in midbrain dopaminergic cells.

Mutations in HPRT1, a gene encoding a rate-limiting enzyme for purine salvage, cause Lesch-Nyhan disease which is characterized by self-injury and motor impairments. We leveraged stem cell and genetic engineering technologies to model the disease in isogenic and patient-derived forebrain and midbrain cell types. Dopaminergic progenitor cells deficient in HPRT showed decreased intensity of all developmental cell-fate markers measured. Metabolic analyses revealed significant loss of all purine derivatives, except hypoxanthine, and impaired glycolysis and oxidative phosphorylation. real-time glucose tracing demonstrated increased shunting to the pentose phosphate pathway for de novo purine synthesis at the expense of ATP production. Purine depletion in dopaminergic progenitor cells resulted in loss of RHEB, impairing mTORC1 activation. These data demonstrate dopaminergic-specific effects of purine salvage deficiency and unexpectedly reveal that dopaminergic progenitor cells are programmed to a high-energy state prior to higher energy demands of terminally differentiated cells.

Stimulation of L-type calcium channels increases tyrosine hydroxylase and dopamine in ventral midbrain cells induced from somatic cells.

Making high-quality dopamine (DA)-producing cells for basic biological or small molecule screening studies is critical for the development of novel therapeutics for disorders of the ventral midbrain. Currently, many ventral midbrain assays have low signal-to-noise ratio due to low levels of cellular DA and the rate-limiting enzyme of DA synthesis, tyrosine hydroxylase (TH), hampering discovery efforts. Using intensively characterized ventral midbrain cells derived from human skin, which demonstrate calcium pacemaking activity and classical electrophysiological properties, we show that an L-type calcium agonist can significantly increase TH protein levels and DA content and release. Live calcium imaging suggests that it is the immediate influx of calcium occurring simultaneously in all cells that drives this effect. Genome-wide expression profiling suggests that L-type calcium channel stimulation has a significant effect on specific genes related to DA synthesis and affects expression of L-type calcium receptor subunits from the CACNA1 and CACNA2D families. Together, our findings provide an advance in the ability to increase DA and TH levels to improve the accuracy of disease modeling and small molecule screening for disorders of the ventral midbrain, including Parkinson's disease.

Differentiation of Human Induced Pluripotent Stem Cells (iPSCs) into an Effective Model of Forebrain Neural Progenitor Cells and Mature Neurons.

Induced Pluripotent Stem Cells (iPSCs) are pluripotent stem cells that can be generated from somatic cells, and provide a way to model the development of neural tissues in vitro. One particularly interesting application of iPSCs is the development of neurons analogous to those found in the human forebrain. Forebrain neurons play a central role in cognition and sensory processing, and deficits in forebrain neuronal activity contributes to a host of conditions, including epilepsy, Alzheimer's disease, and schizophrenia. Here, we present our protocol for differentiating iPSCs into forebrain neural progenitor cells (NPCs) and neurons, whereby neural rosettes are generated from stem cells without dissociation and NPCs purified from rosettes based on their adhesion, resulting in a more rapid generation of pure NPC cultures. Neural progenitor cells can be maintained as long-term cultures, or differentiated into forebrain neurons. This protocol provides a simplified and fast methodology of generating forebrain NPCs and neurons, and enables researchers to generate effective in vitro models to study forebrain disease and neurodevelopment. This protocol can also be easily adapted to generate other neural lineages.

[A pilot study of ocular diseases screening for neonates in China].

OBJECTIVE: To explore the clinical strategies for the screening of newborn eye diseases and obtain information concerning the incidence of newborn ocular diseases. METHODS: Newborns in a baby-friendly nursery were evaluated for mass screening of eye diseases 2 to 7 days after birth (including reaction to light stimulation, external ocular examination and test for pupil red reflex) and those with abnormalities were subjected to diagnostic examination (external ocular examination with a hand-held slit-lamp, pupil red reflex and mydriatic examination). Newborns in neonatal intensive care unit (NICU) were subjected to screening 5 to 14 days after birth and then, together with those with high risk factors, received a comprehensive examination for screening and diagnostic purposes. The suspected cases were referred to department of ophthalmology for definite diagnosis. RESULTS: Among the 15,398 (91.65%) newborns who were enrolled the screening program, 12 different eye diseases (involving 1266 cases) were detected, with a prevalence of 8.22%. Of these eye diseases, 7 were congenital ocular diseases, involving 809 cases (5. 254%) and including congenital ptosis in 2 cases (0.013%), congenital corneal opacity in 6 cases (0.039%), persistent pupillary membrane in 724 cases (4.702%), congenital cataract in 15 cases (0.097%), persistent hyaloid artery in 54 cases (0.351%), obstruction of nasolacrimal duct in 7 cases (0.046%) and lacrimal gland prolapse in 1 cases (0.007%). Five different diseases (457 cases, 2. 968%) detected were acquired in nature, including neonatal conjunctivitis in 391 case (2.539%), vitreous hemorrhage in 6 cases (0.039%), retinal hemorrhage in 34 cases (0.221%), and neonatal dacryocystitis in 23 cases (0.149%). Of 27 premature babies with body weight lower than 1500 g, 3 had retinopathy of prematurity (ROP, 6 eyes involved). CONCLUSIONS: Early intervention is of great importance for the prevention and treatment of neonatal ocular diseases. The screening of newborn ocular diseases is not only feasible but also effective in the monitoring and control of the eye diseases in neonates.

Disruption of GRIN2B Impairs Differentiation in Human Neurons.

Heterozygous loss-of-function mutations in GRIN2B, a subunit of the NMDA receptor, cause intellectual disability and language impairment. We developed clonal models of GRIN2B deletion and loss-of-function mutations in a region coding for the glutamate binding domain in human cells and generated neurons from a patient harboring a missense mutation in the same domain. Transcriptome analysis revealed extensive increases in genes associated with cell proliferation and decreases in genes associated with neuron differentiation, a result supported by extensive protein analyses. Using electrophysiology and calcium imaging, we demonstrate that NMDA receptors are present on neural progenitor cells and that human mutations in GRIN2B can impair calcium influx and membrane depolarization even in a presumed undifferentiated cell state, highlighting an important role for non-synaptic NMDA receptors. It may be this function, in part, which underlies the neurological disease observed in patients with GRIN2B mutations.

A case-control study on high-risk factors for newborn hearing loss in seven cities of Shandong province.

To investigate the high-risk factors for newborn hearing loss and to provide information for preventing the development of hearing loss and delaying its progression, from May 2003 to June 2006, neonates who failed to pass the universal newborn hearing screening (UNHS) were referred to Jinan Newborn Hearing Screening and Rehabilitation Center from 7 newborn hearing screening centers in seven cities of Shandong province. One-to-one pair-matched case-control method was employed for statistical analysis of the basic features of definitely identified cases. High-risk factors relating to the bilateral hearing loss were evaluated by univariate and multivariate Logistic regression analysis. Our results revealed that 721 transferred newborns who didn't pass the hearing screening received audiological and medical evaluation and 367 were confirmed to have hearing loss. Of them, 177 neonates with hearing loss who met the matching requirements were included in the study as subjects. Univariate analysis showed that high-risk factors related to hearing loss incuded age of father, education backgrounds of parents, parity, birth weight, gestational weeks, craniofacial deformity, history of receiving treatment in neonatal intensive care unit (NICU), neonatal disease, family history of otopathy and family history of congenital hearing loss. Multivariate Logistic regression analysis revealed that 4 independent risk factors were related to bilateral hearing loss, including parity (OR=16.285, 95% CI 3.379-78.481), neonatal disease (OR=34.968, 95% CI 2.720-449.534), family history of congenital hearing loss (OR=69.488, 95% CI 4.417-1093.300) and birth weight (OR=0.241, 95% CI 0.090-0.648). It is concluded that parity, neonatal disease and family history of hearing loss are the promoting factors of bilateral hearing loss in neonates and appropriate intervention measures should be taken to deal with the risk factors.

Starch-derived absorbable polysaccharide hemostat enhances bone healing via BMP-2 protein.

Surgical hemostasis is critical in reducing the likelihood of excessive bleeding and blood transfusion. In treating some cases, commonly used hemostatic agent showed limited efficacy and prolonged degradation and clearance, causing an inhibition of bone healing. Starch absorbable polysaccharide (SAPH) is a novel hemostatic agent made from a plant starch, which can be completely absorbed and achieve better hemostatic effects than many commonly used hemostatic agents. However, whether SAPH can induce a promotion of bone healing remains unknown. In this study, we used a model of rabbit parietal bone defect and a mouse osteoblast cell line MC3T3-E1 to evaluate the effects of SAPH on bone healing. We found that SAPH significantly decreased bone healing scores, reduced defective area of parietal bone, and increased the areas of bone trabeculae and cavitas medullaris. In addition, SAPH enhanced MC3T3-E1 osteoblasts proliferation, up-regulated the expressions of alkaline phosphatase (ALP) and osteocalcin and increased the level of bone morphogenetic protein 2 (BMP-2) in MC3T3-E1 osteoblasts. These SAPH-induced benefits in MC3T3-E1 osteoblasts were significantly abolished by the application of BMP-2-siRNA. These findings suggested that SAPH enhances bone healing, promotes the proliferation, differentiation and maturation of osteoblast by up-regulating BMP-2 expression in osteoblastic cells.

Neuron-specific Enolase and myelin basic protein in cerebrospinal fluid of patients with first episode schizophrenia.

In order to study whether patients with schizophrenia have cerebral injury, neuron-specific enolase (NSE) and myelin basic protein (MBP)in cerebrospinal fluid (CSF) of 33 patients with first episode schizophrenia and 9 from the control group were determined by double antibody sandwich enzyme immunoassay method. The results showed that there was significant difference in the NSE contents between the experimental group and control group (P<0.01). The NSE contents in CSF in the experimental group were positively correlated with MBP in schizophrenia patients (P< 0. 05). These findings suggested that patients with schizophrenia had cerebral injury.

Study on self-consciousness of children with learning disabilities and related factors.

OBJECTIVE: To study the self-consciousness of children with learning disabilities (LD) and to identify related factors. METHODS: Five hundred and sixty pupils graded from 1 to 6 in an elementary school were investigated. According to the pupil rating scale revised screening for learning disabilities (PRS), combined Raven's test (CRT) and achievement of main courses, 35 of 560 pupils were diagnosed as LD children. Thirty-five children were selected from the average children and 35 from advanced children in academic achievement equally matched in class, gender, and age with LD children as control groups. The three groups were tested by Piers-Harris children's self-concept scale. Basic information of each subject was collected by self-made questionnaire. RESULTS: Compared with the average and advanced children, LD children got significantly lower scores in self-concept scale. Based on logistic regression analysis, 3 factors were identified, including family income per month, single child and delivery model. CONCLUSION: The results suggest that self-consciousness of children with LD is lower than that of normal children.

Risk factors of learning disabilities in Chinese children in Wuhan.

OBJECTIVE: To investigate prevalence rate of learning disabilities (LD) in Chinese children, and to explore related risk factors, and to provide theoretical basis for preventing such disabilities. METHODS: One thousand and one hundred fifty one children were randomly selected in primary schools. According to criteria set by ICD-10, 118 children diagnosed as LD were classified into the study group. Four hundred and ninety one children were classified into the normal control group. Five hundred and forty two children were classified into the excellent control group. The study instruments included PRS (The pupil rating scale revised screening for learning disabilities), Conners' children behavior check-list taken by parents and YG-WR character check-list. RESULTS: The prevalence rate of LD in Chinese children was 10.3%. Significant differences were observed between LD and normally learning children, and between the LD group and the excellent group, in terms of scores of Conners' behavior check-list (P < 0.05). The study further showed that individual differences in character between the LD group and the control groups still existed even after controlling individual differences in age, IQ, and gender. Some possible causal explanations contributing to LD were improper teaching by parents, low educational level of the parents, and children's characteristics and social relationships. CONCLUSION: These data underscore the fact that LD is a serious national public health problem in China. LD is resulted from a number of factors. Good studying and living environments should be created for LD children.

A bibliometric analysis of research on the behavior therapy in China and its trend.

To get formed of the status of research and application of the domestic behavior therapy and its development trend, the time distribution and the subject distribution were bibliometrically analyzed of the literature on behavior therapy from 1981 to 2000 in the CBMdisc. Our results showed that the number of literature of behavior therapy has been increasing in exponential manner over the past 20 years; the behavior modification, the biofeedback and the cognitive therapy are extensively used in China. In clinical practice, the behavior modification and the biofeedback have been applied in all departments of medical institutions, especially for treating the cardiovascular and the neurological conditions. The cognitive therapy has been employed mainly for the treatment of mental disorders (or dysphrenia), the aversive therapy mainly for material withdrawal, and the systematic desensitization for phobia. There was no report found on the clinical use of meditation. It is concluded that the study and application in behavior therapy in China is currently developing very fast.

Working-memory training improves developmental dyslexia in Chinese children.

Although plasticity in the neural system underlies working memory, and working memory can be improved by training, there is thus far no evidence that children with developmental dyslexia can benefit from working-memory training. In the present study, thirty dyslexic children aged 8-11 years were recruited from an elementary school in Wuhan, China. They received working-memory training, including training in visuospatial memory, verbal memory, and central executive tasks. The difficulty of the tasks was adjusted based on the performance of each subject, and the training sessions lasted 40 minutes per day, for 5 weeks. The results showed that working-memory training significantly enhanced performance on the nontrained working memory tasks such as the visuospatial, the verbal domains, and central executive tasks in children with developmental dyslexia. More importantly, the visual rhyming task and reading fluency task were also significantly improved by training. Progress on working memory measures was related to changes in reading skills. These experimental findings indicate that working memory is a pivotal factor in reading development among children with developmental dyslexia, and interventions to improve working memory may help dyslexic children to become more proficient in reading.

Prevalence and factors of addictive Internet use among adolescents in Wuhan, China: interactions of parental relationship with age and hyperactivity-impulsivity.

PURPOSES: This study examined the prevalence of addictive Internet use and analyzed the role of parental relationship in affecting this behavior among a random sample of adolescents in Wuhan, China. METHODS: Students (n = 1,101) were randomly selected from four schools, including 638 boys and 463 girls with a mean age of 13.8 (standard deviation = 1.2) years. Addictive Internet use, parental relationship, hyperactivity-impulsivity were measured by validated instruments. Prevalence rate, ANOVA and multiple linear regression method were used to analyze the level of Internet addiction and its association with parental relationship, hyperactivity-impulsivity, as well as the interaction of parental relationship with chronological age and hyperactivity-impulsivity. RESULTS: The prevalence rate of Internet addiction was 13.5% (16.5% for boys and 9.5% for girls, p<0.01). Compared to non-addictive users, addictive Internet users were scored significantly lower on parental relationships and significantly higher on hyperactivity-impulsivity. Interaction analysis indicated that better parental relationship was associated with more reductions in risk of addictive Internet use for younger students than for older students, and with more risk of Internet addiction among higher than among lower hyperactivity-impulsivity students. CONCLUSIONS: Findings of this study indicate that adolescent addictive Internet use is a significant public health threat in China. Prevention interventions targeting parental relationship must consider adolescent's age and hyperactivity-impulsivity tendency.

Association of polymorphisms in the DCDC2 gene with developmental dyslexia in the Han Chinese.

BACKGROUND: Genetic association studies on populations of European origin have identified the DCDC2 gene as a susceptibility locus for developmental dyslexia. Here, we sought to investigate the association of DCDC2 polymorphisms with developmental dyslexia in children of Han Chinese origin. METHODS: We undertook a case-control genetic association study on 76 dyslexic children and 79 non-dyslexic matched controls. We isolated DNA from oral mucosal cell samples and genotyped two DCDC2 coding-sequence single nucleotide polymorphisms, rs2274305 and rs6456593, in each sample using SNaPshot single nucleotide extension. We compared the allele and genotype frequencies between the groups using the χ(2) test and analyzed the relationship between dyslexia and the polymorphism at both loci using unconditional logistic regression. We also predicted haplotypes and compared their frequencies between the two groups. RESULTS: The differences in the genotype distribution and the allelic genes of the two single nucleotide luci of the DCDC2 gene, rs2274305 and rs6456593, between the two dyslexic and non-dyslexic groups were statistically meaningless (P > 0.05). The differences in the haplotype distributions of the DCDC2 gene between the dyslexic and normal group were statistically meaningless (P > 0.05). CONCLUSION: The DCDC2 gene may not be a susceptibility factor for developmental dyslexia among the Han Chinese. However, methodological issues may have prevented the detection of positive associations.