A functional neuron maturation device provides convenient application on microelectrode array for neural network measurement.

BACKGROUND: Microelectrode array (MEA) systems are valuable for in vitro assessment of neurotoxicity and drug efficiency. However, several difficulties such as protracted functional maturation and high experimental costs hinder the use of MEA analysis requiring human induced pluripotent stem cells (hiPSCs). Neural network functional parameters are also needed for in vitro to in vivo extrapolation. METHODS: In the present study, we produced a cost effective nanofiber culture platform, the SCAD device, for long-term culture of hiPSC-derived neurons and primary peripheral neurons. The notable advantage of SCAD device is convenient application on multiple MEA systems for neuron functional analysis. RESULTS: We showed that the SCAD device could promote functional maturation of cultured hiPSC-derived neurons, and neurons responded appropriately to convulsant agents. Furthermore, we successfully analyzed parameters for in vitro to in vivo extrapolation, i.e., low-frequency components and synaptic propagation velocity of the signal, potentially reflecting neural network functions from neurons cultured on SCAD device. Finally, we measured the axonal conduction velocity of peripheral neurons. CONCLUSIONS: Neurons cultured on SCAD devices might constitute a reliable in vitro platform to investigate neuron functions, drug efficacy and toxicity, and neuropathological mechanisms by MEA.

Edoxaban suppresses the progression of atrial fibrosis and atrial fibrillation in a canine congestive heart failure model.

Coagulation factor Xa activates the protease-activated receptor 2 (PAR2) and causes tissue fibrosis; however, the effects of Xa inhibitor edoxaban on atrial fibrosis and atrial fibrillation (AF) have not been investigated. We examined the effect of edoxaban on the progression of atrial fibrosis in a canine congestive heart failure (CHF) model. Beagle dogs were assigned to sham, placebo, and edoxaban groups (n = 6/group). Dogs of the placebo or edoxaban groups received 19 days of medication with daily oral placebo or edoxaban, respectively, followed by 14 days of ventricular tachypacing. Dogs of the sham group had no medication or pacing. Ventricular tachypacing prolonged AF duration in dogs of the placebo group (159 ± 41 s, p < 0.01 vs. sham); however, this effect was suppressed by edoxaban treatment. Compared with the sham group, tachypacing alone also significantly increased the atrial fibrotic area (2.9 ± 0.1% vs. 7.8 ± 0.4%, p < 0.01), PAR2 expression (1.0 ± 0.1 vs. 1.8 ± 0.3, p < 0.05), and atrial fibronectin expression (1.0 ± 0.2 vs. 2.0 ± 0.2, p < 0.01). These responses were suppressed by edoxaban treatment (area 5.9 ± 0.4%, p < 0.01; PAR2 1.1 ± 0.1, p < 0.05; fibronectin 1.2 ± 0.2, p < 0.05 vs. placebo). Edoxaban showed suppressive effects on atrial remodeling, AF progression, and excessive expressions of PAR2 and fibronectin in a canine CHF model. The suppression of the Xa/PAR2 pathway might be a potential pharmacological target of edoxaban.

Lack of modulatory effect of the SCN5A R1193Q polymorphism on cardiac fast Na+ current at body temperature.

SCN5A encodes the main subunit of the NaV1.5 channel, which mediates the fast Na+ current responsible for generating cardiac action potentials. The single nucleotide polymorphism SCN5A(R1193Q), which results in an amino acid replacement in the subunit, is common in East Asia. SCN5A(R1193Q) is often identified in patients with type 3 long QT syndrome and Brugada syndrome. However, its linkage to arrhythmic disorders is under debate. Previous electrophysiological studies performed at room temperature inconsistently reported the gain- or loss-of-function effect of SCN5A(R1193Q) on the NaV1.5 channel. More recently, it was theoretically predicted that SCN5A(R1193Q) would exert a loss-of-function effect at body temperature. Here, we experimentally assessed whether SCN5A(R1193Q) modulates the NaV1.5 channel at various temperatures including normal and febrile body temperatures. We compared voltage-gated Na+ currents in SCN5A(R1193Q)-transfected and wild-type SCN5A-transfected HEK293T cells using a whole-cell voltage-clamp technique. First, we made comparisons at constant temperatures of 25°C, 36.5°C, and 38°C, and found no difference in the conductance density, voltage dependence of gating, or time dependence of gating. This suggested that SCN5A(R1193Q) does not modulate the NaV1.5 channel regardless of temperature. Second, we made comparisons while varying the temperature from 38°C to 26°C in 3 min, and again observed no difference in the time course of the amplitude or time dependence of gating during the temperature change. This also indicated that SCN5A(R1193Q) does not modulate the NaV1.5 channel in response to an acute body temperature change. Therefore, SCN5A(R1193Q) may not be a monogenic factor that triggers arrhythmic disorders.

A mutant HCN4 channel in a family with bradycardia, left bundle branch block, and left ventricular noncompaction.

We found that a female infant presenting with left bundle branch block and left ventricular noncompaction carries uninvestigated gene mutations HCN4(G811E), SCN5A(L1988R), DMD(S2384Y), and EMD(R203H). Here, we explored the possible pathogenicity of HCN4(G811E), which results in a G811E substitution in hyperpolarization-activated cyclic nucleotide-gated channel 4, the main subunit of the cardiac pacemaker channel. Voltage-clamp measurements in a heterologous expression system of HEK293T cells showed that HCN4(G811E) slightly reduced whole-cell HCN4 channel conductance, whereas it did not affect the gating kinetics, unitary conductance, or cAMP-dependent modulation of voltage-dependence. Immunocytochemistry and immunoblot analysis showed that the G811E mutation did not impair the membrane trafficking of the channel subunit in the heterologous expression system. These findings indicate that HCN4(G811E) may not be a monogenic factor to cause the cardiac disorders.

MicroRNA-145-5p and microRNA-320a encapsulated in endothelial microparticles contribute to the progression of vasculitis in acute Kawasaki Disease.

Kawasaki Disease (KD) is an acute inflammatory disease that takes the form of systemic vasculitis. Endothelial microparticles (EMPs) have been recognized as an important transcellular delivery system. We hypothesized whether EMPs are involved in vasculitis in acute KD. Fifty patients with acute KD were enrolled, divided into two subgroups: those with coronary artery lesions (CAL) (n = 5) and those without CAL (NCAL) (n = 45). EMPs were measured using flow cytometry, and microRNA (miR) expression profiling was performed by microRNA array. The percentage of EMPs in acute KD was significantly higher than in controls (P < 0.0001). EMPs in patients with CAL rapidly increased after the initial treatment, and was significantly higher than those in NCAL (P < 0.001). In patients with CAL, we identified 2 specific miRs encapsulated in EMPs, hsa-miR-145-5p and hsa-miR-320a, which are predicted to affect monocyte function using in silico analysis, and were demonstrated to upregulate inflammatory cytokine mRNAs in THP-1 monocytes. In situ hybridization confirmed that hsa-miR-145-5p was preferentially expressed in CAL. EMPs may serve as a sensitive marker for the severity of vasculitis in acute KD. Moreover, these 2 specific miRs encapsulated in EMPs might be involved in inflammatory cytokine regulation and the pathogenesis of vasculitis in acute KD.

An Autopsy Case of Sudden Unexpected Death of a Young Adult in a Hot Bath: Molecular Analysis Using Next-Generation DNA Sequencing.

We report a case of sudden unexpected death of a young woman who was found in a bathtub of hot water. The autopsy concluded that all possible causes of sudden loss of consciousness, except cardiac origin, could be excluded. However, the heart did not show any obvious pathological changes. We used next-generation DNA sequencing (NGS) to examine 73 genes and detected 3 rare, potentially pathogenic variants with minor allele frequencies ⩽1.0%. The pathogenicity of these variants was evaluated using 8 in silico predictive algorithms, and SCN5A_p.Gly289Ser, CACNB2_p.Ser502Leu, and MYH11_p.Lys1573Glu were detected as possible pathogenic variants. Inherited heart disease is a likely cause of sudden unexpected deaths of young people in hot baths, even before the clinical manifestation of the disease. In the future, molecular analysis by NGS may help to predict young to early middle-aged people who could be at risk of sudden arrhythmogenic fatality in hot baths.

Incipient progressive supranuclear palsy is more common than expected and may comprise clinicopathological subtypes: a forensic autopsy series.

We investigated 998 serial Japanese forensic autopsy cases (0-101 years old, mean age 61.7 ± 21.9), with no case selection, using immunohistochemistry to detect cases with progressive supranuclear palsy (PSP). Twenty-nine cases (mean age 82.3 ± 7.2 years, 11 males, 18 females) fulfilled the National Institute of Neuronal Disorders and Stroke (NINDS)-PSP pathological criteria (2.9% of all cases, 4.6% of cases over 60). All had neuronal and glial inclusions in the basal ganglia and brainstem. However, 13 cases had low tau pathology and were categorized as atypical PSP. In addition to PSP pathology, multiple types of astrocytic inclusions and comorbid proteinopathies, particularly a high prevalence of argyrophilic grain disease, were found. All cases had not been diagnosed with PSP and had preserved daily functioning prior to death. However, 14 (48.3%), 11 (37.9%), and 16 (55.2%) cases showed signs of dementia, depressive state, and gait disturbance, respectively. Sixteen accidental death cases (55.2%), including from falls and getting lost, and 11 suicide cases (37.9%) appear to have a relationship with incipient PSP pathology. Cluster analysis using the distribution and amount of 4-repeat-tau pathology classified the cases into three subgroups: Group 1 (10 cases) had typical PSP pathology and seven cases (70.0%) had dementia as the most frequent symptom; Group 2 (7 cases) had significantly higher frequency of gait disorder (6 cases, 85.7%), and less neocortical tau pathology than Group 1; Group 3 (12 cases) had relatively mild PSP pathology and high argyrophilic grain burdens. Granular-shaped astrocytes were the dominant astrocytic inclusion in all cases. We conclude that in forensic cases incipient PSP occurs with a higher prevalence than expected. If these findings can be extrapolated to other population-based cohorts, PSP may be more common than previously thought.

Epilepsy-related sudden unexpected death: targeted molecular analysis of inherited heart disease genes using next-generation DNA sequencing.

Inherited heart disease causing electric instability in the heart has been suggested to be a risk factor for sudden unexpected death in epilepsy (SUDEP). The purpose of this study was to reveal the correlation between epilepsy-related sudden unexpected death (SUD) and inherited heart disease. Twelve epilepsy-related SUD cases (seven males and five females, aged 11-78 years) were examined. Nine cases fulfilled the criteria of SUDEP, and three cases died by drowning. In addition to examining three major epilepsy-related genes, we used next-generation sequencing (NGS) to examine 73 inherited heart disease-related genes. We detected both known pathogenic variants and rare variants with minor allele frequencies of <0.5%. The pathogenicity of these variants was evaluated and graded by eight in silico predictive algorithms. Six known and six potential rare variants were detected. Among these, three known variants of LDB3, DSC2 and KCNE1 and three potential rare variants of MYH6, DSP and DSG2 were predicted by in silico analysis as possibly highly pathogenic in three of the nine SUDEP cases. Two of three cases with desmosome-related variants showed mild but possible significant right ventricular dysplasia-like pathology. A case with LDB3 and MYH6 variants showed hypertrabeculation of the left ventricle and severe fibrosis of the cardiac conduction system. In the three drowning death cases, one case with mild prolonged QT interval had two variants in ANK2. This study shows that inherited heart disease may be a significant risk factor for SUD in some epilepsy cases, even if pathological findings of the heart had not progressed to an advanced stage of the disease. A combination of detailed pathological examination of the heart and gene analysis using NGS may be useful for evaluating arrhythmogenic potential of epilepsy-related SUD.

Effect of irbesartan on development of atrial fibrosis and atrial fibrillation in a canine atrial tachycardia model with left ventricular dysfunction, association with p53.

Effects of an angiotensin II receptor blocker, irbesartan (IRB), on the development of atrial fibrosis and atrial fibrillation (AF) were assessed in a canine model of atrial tachycardia remodeling (ATR) with left ventricular dysfunction, together with its possible association with involvement of p53. Atrial tachypacing (400 bpm for 4 weeks) was used to induce ATR in beagles treated with placebo (ATR-dogs, n = 6) or irbesartan (IRB-dogs, n = 5). Non-paced sham dogs served as control (Control-dogs, n = 4). ATR- and IRB-dogs developed tachycardia-induced left ventricular dysfunction. Atrial effective refractory period (AERP) shortened (83 ± 5 ms, p < 0.05), inter-atrial conduction time prolonged (72 ± 2 ms, p < 0.05), and AF duration increased (29 ± 5 s, p < 0.05 vs. baseline) after 4 weeks in ATR-dogs. ATR-dogs also had a larger area of atrial fibrous tissue (5.2 ± 0.5 %, p < 0.05 vs. Control). All these changes, except for AERP, were attenuated in IRB-dogs (92 ± 3 ms, 56 ± 3 ms, 9 ± 5 s, and 2.5 ± 0.7 %, respectively; p < 0.05 vs. ATR for each). In ATR-dogs, p53 expression in the left atrium decreased by 42 % compared with Control-dogs (p < 0.05); however, it was highly expressed in IRB-dogs (+89 % vs. ATR). Transforming growth factor (TGF)-ß1 expression was enhanced in ATR-dogs (p < 0.05 vs. Control) but reduced in IRB-dogs (p < 0.05 vs. ATR). Irbesartan suppresses atrial fibrosis and AF development in a canine ATR model with left ventricular dysfunction in association with p53.

MicroRNA-93 may control vascular endothelial growth factor A in circulating peripheral blood mononuclear cells in acute Kawasaki disease.

BACKGROUND: Kawasaki disease (KD) is the most common systemic vasculitis syndrome primarily affecting medium-sized arteries, particularly the coronary arteries. Though KD may be associated with immunological problems, the involvement of microRNAs (miRs) has not been fully described. METHODS: We enrolled 23 KD patients and 12 controls. We performed miR and mRNA microarray analysis of peripheral blood mononuclear cells (PBMCs) isolated from acute KD patients and controls. Continuously, we measured specific miRs, mRNA and the expression of proteins by using reverse-transcriptase PCR (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). RESULTS: We identified strikingly high levels of miR-182 and miR-296-5p during the acute febrile phase, and of miR-93, miR-145-5p, miR-145-3p, and miR-150-3p in the defervescence stage, especially in refractory KD patients. The expression of vascular endothelial growth factor A (VEGFA) mRNA, previously reported to be controlled by miR-93, was significantly elevated during the febrile phase and normalized upon treatment, negatively correlating with the expression of miR-93. Further, plasma levels of VEGF-A correlated with PBMC VEGFA mRNA expression. CONCLUSION: Several miRs are highly specific to the acute phase of KD, and may participate in regulating the expression of genes in pathways associated with KD. In particular, miR-93 may participate in regulating expression of VEGF-A and contribute to the pathogenesis of arteritis in acute KD.

Postmortem genetic analysis of sudden unexplained death syndrome under 50 years of age: A next-generation sequencing study.

BACKGROUND: Recent studies on the genetic analysis of victims of sudden unexplained death syndrome (SUDS) have shown diagnostic potential. Previously, such analyses mainly targeted the major channelopathy-associated genes. OBJECTIVE: The purpose of this study was to evaluate the utility of next-generation sequencing (NGS) in the postmortem diagnosis of SUDS. METHODS: Our data are derived from 25 cases of SUDS (21 men and 4 women; age 19-50 years). A total of 70 genes were examined by NGS, and the pathogenicity of any detected rare variants with minor allele frequencies of <0.5% was evaluated using a widely used database and eight in silico algorithms. RESULTS: Five known and 15 potentially pathogenic variants with a high in silico score were identified in 14 cases. In all, 6 channelopathy-related variants were identified in 5 cases, including 2 cases with history of arrhythmia; 11 cases had cardiomyopathy- or cardiac transcription factor-related variants. Three cases with desmosomal gene- or other cardiomyopathy-related variants showed possibly related pathologic changes. Three cases with RYR2 or TBX5 variants showed possible pathogenic fibrosis of the cardiac conduction system. Only 12 variants showed moderate or strong possible pathogenicity in SUDS cases compared with qualifying controls. CONCLUSION: Hereditary heart diseases other than channelopathy may also be a significant cause of SUDS, even if clinical and pathologic findings do not show advanced disease. A combination of gene analysis using NGS and some predictive methods for detecting variants and careful pathologic evaluation may provide a reliable diagnosis of hereditary heart disease for potential SUDS cases.

SCN5A(K817E), a novel Brugada syndrome-associated mutation that alters the activation gating of NaV1.5 channel.

BACKGROUND: Brugada syndrome (BrS) is an inherited lethal arrhythmic disorder characterized by syncope and sudden cardiac death from ventricular tachyarrhythmias. Here we identified a novel K817E mutation of SCN5A gene in a man with type 1 BrS electrocardiogram pattern using next-generation sequencing targeted for 73 cardiac disorder-related genes. SCN5A encodes the α-subunit of NaV1.5 voltage-gated Na(+) channel, and some of its mutations are linked to BrS. The proband had no mutation in any of the other arrhythmia-related genes sequenced. OBJECTIVE: We investigated whether the K817E mutation causes a functional change of NaV1.5 channel responsible for the BrS phenotype. METHODS: We compared the electrophysiological properties of the whole-cell currents mediated by wild-type and mutant channels heterologously expressed in human embryonic kidney 293 cells by using a voltage-clamp technique. RESULTS: The K817E mutation reduced the Na(+) current density by 39.0%-91.4% at membrane potentials from -55 to -5 mV. This reduction resulted from a ~24-mV positive shift in the voltage dependence of activation. The mutation also decelerated recovery from both fast and intermediate inactivation, whereas it had little effect on the cell surface expression, single-channel conductance, voltage-dependence of fast inactivation, entry into intermediate inactivation, use-dependent loss of channel availability, or closed-state inactivation. CONCLUSION: The K817E mutation of SCN5A gene leads to loss of function of NaV1.5 channel and may underlie the BrS phenotype of the proband.

The Susceptibilities of Human Ether-à-Go-Go-Related Gene Channel with the G487R Mutation to Arrhythmogenic Factors.

The human ether-à-go-go-related gene (hERG) channel mediates the rapid delayed rectifier potassium current (IKr) responsible for shaping the repolarization phase of cardiac action potentials. hERG mutation may cause hERG channel malfunction, leading to long QT syndrome and other arrhythmic disorders. Elucidation of the genotype-phenotype relationships of individual hERG mutations is key to the development of treatment for such arrhythmic disorders. We previously identified hERG(G487R), a missense mutant with a glycine-to-arginine substitution at position 487. In the absence of arrhythmogenic factors, hERG(G487R) subunit-containing channels show normal surface expression and gating kinetics. However, it remains unknown whether the mutation exacerbates hERG channel malfunction induced by arrhythmogenic factors. Here we used a voltage-clamp technique to compare the effects of the major arrythmogenic factors on wild-type hERG [hERG(WT)] and hERG(G487R) channel currents (IhERG) in HEK-293T cells. The extent of IhERG blockade by the antiarrhythmic drug dofetilide or E4031 was not different between these channels. On the other hand, the extracellular K(+) concentration ([K(+)]ex)-dependent changes in the rates of recovery from inactivation and deactivation of IhERG were rather less obvious for hERG(G487R) channel than for hERG(WT) channel. These findings suggest that the inheritance of hERG(G487R) does not increase the risk of arrhythmic disorders induced by antiarrhythmic drugs or hypokalemia.

Neuropathologic features of suicide victims who presented with acute poststroke depression: significance of association with neurodegenerative disorders.

To investigate the neuropathologic characteristics of poststroke depression (PSD) leading to suicide, we retrospectively selected deceased subjects who had been diagnosed as having early PSD. Cases were divided into subjects who had committed suicide and those who had not. Neuropathologic examinations, including immunohistochemistry, were conducted. Twenty-four subjects fulfilled criteria for early PSD; 11 of these had committed suicide, and the other 13 had not. Lesion type, size of stroke, and location of stroke were variable but did not differ significantly between the groups. Alzheimer disease-related pathology stages also did not differ between the groups. Argyrophilic grain disease was found in both the suicide group (6 of 11) and the nonsuicide group (2 of 13); there were 2 highly possible cases of early progressive supranuclear palsy in the suicide group. Together, argyrophilic grain disease and progressive supranuclear palsy were found significantly more frequently in suicide cases than in nonsuicide cases (p = 0.01). These data suggest that overlapping 4-repeat tauopathies, which include argyrophilic grain disease and progressive supranuclear palsy, might be an important aggravating factor of PSD that could lead to suicide. The presence of other neurodegenerative diseases does not preclude PSD because the prevalence of these diseases in older persons suggests that they might often occur concomitantly.

Pathological features of preclinical or early clinical stages of corticobasal degeneration: a comparison with advanced cases.

AIMS: The manner in which pathological lesions of corticobasal degeneration (CBD) progress remains poorly understood. Because the pathology of early disease stages may be fundamental for elucidating a border between clinical and preclinical states of CBD, the present study aimed to detect preclinical or early clinical CBD cases by examining a series of forensic autopsy cases. METHODS: A series of 887 brains from medicolegal autopsies was examined. Immunohistochemistry for tau (AT8, 3, and 4-repeat-tau) and Gallyas-Braak was applied for diagnosis. Neuropathological diagnosis of CBD followed criteria updated in 2002 by a working group. RESULTS: Three autopsy cases (0.34%) were identified that fulfilled CBD pathological criteria. Two cases were preclinical or very early clinical cases without brain atrophy; the other case had exhibited a 5-year history of advanced frontotemporal dementia. Significant microscopic differences between the subclinical and clinical cases included occurrence of neuronal loss with spongiosis and gliosis, as well as a difference in degree of tau pathology in the superficial layer of the neocortical areas and white matter. Anatomical hierarchy of tau pathology in the brain was not evident, but asymmetric neocortical tau pathology that might influence the clinical phenotype was found in preclinical and early clinical cases. CONCLUSIONS: The results revealed the pathological features of subclinical and early clinical CBD cases. Comparison with clinical CBD cases showed that neuronal loss, cortical atrophy and volume reduction of white matter may be involved in the occurrence of clinical symptoms of CBD. Additionally, immunohistochemistry is essential for detecting preclinical CBD cases, regardless of case selection.

Anomalous origin of the right coronary artery from the left coronary sinus with an intramural course: comparison between sudden-death and non-sudden-death cases.

BACKGROUND: The prognosis of patients in whom the right coronary artery (RCA) arises from the left coronary sinus (LCS) is unequal. An initial intramural course of the coronary artery within the aortic media is considered to cause myocardial ischemia in cases of coronary anomalies. METHODS: Clinicopathological findings in five autopsy cases where the RCA arose from the LCS with an intramural course were examined. Comparison between sudden cardiac death and noncardiac death was also performed. RESULTS: Two of five cases were sudden cardiac death, and the other three cases were noncardiac death. In one case of sudden death, the person collapsed during light exercise, and in the other case, the person was under the effect of methamphetamine. Both of the cases of sudden death showed an RCA-dominant pattern in distribution of the coronary artery, atherosclerotic narrowing of the RCA, and acute ischemic necrosis in the posterior basilar ventricular septum around the atrioventricular conduction system, which is considered to be the territory of the RCA. CONCLUSIONS: An intramural course within the aortic media may be an accelerating factor of decreased blood flow in cases with an origin of the RCA arising from the LCS because of compression from the aortic lumen. However, this finding may not be an independent predictor of pathological ischemia. Additional factors that diminish blood flow in the intramural segment may be required to cause significant myocardial ischemia. Additionally, inciting factors, which can increase blood pressure, may also play a role in causing symptomatic myocardial ischemia by initiating mechanical compression from the aorta to the intramural segment of the RCA.

An autopsy case of infantile-onset vanishing white matter disease related to an EIF2B2 mutation (V85E) in a hemizygous region.

We report a rare autopsy case of early infantile-onset vanishing white matter disease, with a submicroscopic deletion of 14q24.3, which included EIF2B2 and a missense mutation of EIF2B2 (V85E) of the remaining allele. The patient was a 4-year-old boy, who was found to have suddenly died during sleep. Physical and mental development began to deteriorate after convulsions at 10 month of age, and did not recover to baseline measurements. At autopsy, the brain showed a marked decrease in volume of white matter, with no typical cystic rarefaction. Histopathologically, the affected white matter showed diffuse loss of myelin fibers, meager astrogliosis with dysmorphic astrocytes, and loss of oligodendrocytes. Proliferative and apoptotic markers were negative for oligodendrocytes in the severely affected area. These findings may be related to the severity of the disease, and might be a feature of the EIF2B2 mutation pattern of the patient. Additionally, unusual fatty infiltration of both ventricles of the heart was found. These findings were suspected as early pathology of arrhythmogenic right ventricular cardiomyopathy due to characteristic gene mutation in the present case. In the present case, the defect EIF2B2 caused by hemizygosity may be related to early onset of the disease and the unusual pathological changes with vulnerability of oligodendrocytes and astrocytes, as well as cardiac abnormalities and sudden unexpected death.