A novel in-frame GFAP p.E138_L148del mutation in Type II Alexander disease with atypical phenotypes.

Alexander disease (AxD) is a neurodegenerative astrogliopathy caused by mutation in the glial fibrillary acidic protein (GFAP) gene. A 42-year-old Korean man presented with temporary gait disturbance and psychiatric regression after a minor head trauma in the absence of bulbar symptoms and signs. Magnetic resonance images of the brain and spinal cord showed significant atrophy of the medulla oblongata and the entire spinal cord as well as contrast-enhanced T2 hypointensity in the basal ganglia. DNA sequencing revealed a novel 33-bp in-frame deletion mutation (p.Glu138_Leu148del) within the 1B rod domain of GFAP, which was predicted to be deleterious by PROVEAN analysis. To test whether the deletion mutant is disease-causing, we performed in vitro GFAP assembly and sedimentation assays, and GFAP aggregation assays in human adrenal carcinoma SW13 (Vim-) cells and rat primary astrocytes. All the assays revealed that GFAP p.Glu138_Leu148del is aggregation prone. Based on these findings, we diagnosed the patient with Type II AxD. This is a report that demonstrates the pathogenicity of InDel mutation of GFAP through functional studies. This patient's atypical presentation as well as the discrepancy between clinical symptoms and radiologic findings may extend the scope of AxD.

Fulminant Course of Neuromyelitis Optica in a Patient With Anti-MDA5 Antibody-Positive Dermatomyositis: A Case Report.

Anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibody is a myositis-specific marker detected in clinically amyopathic dermatomyositis (DM). DM with anti-MDA5 antibody can be accompanied by rapidly progressive interstitial lung disease (RP-ILD) and other autoimmune disorders. Until now, only one case of neuromyelitis optica (NMO) with anti-MDA5-positive DM has been reported worldwide, in which the patient achieved a favorable outcome with intensive immunotherapy. We report a case of NMO in a patient with anti-MDA5-positive DM complicated by ILD and rheumatoid arthritis. Our patient experienced a fulminant course of NMO, rather than RP-ILD, in the presence of hyperferritinemia, which resulted in profound neurological sequelae despite immunotherapy including rituximab.

Novel NTRK1 mutations associated with congenital insensitivity to pain with anhidrosis verified by functional studies.

Congenital insensitivity to pain with anhidrosis (CIPA), also known as hereditary sensory and autonomic neuropathy type IV, features loss of pain sensation, decreased or absent sweating (anhidrosis), recurrent episodes of unexplained fever, self-mutilating behavior, and variable mental retardation. Mutations in neurotrophic receptor tyrosine kinase 1 (NTRK1) have been reported to be associated with CIPA. We identified four novel NTRK1 mutations in six Korean patients from four unrelated families. Of the four mutations, we demonstrated using a splicing assay that IVS14+3A>T causes aberrant splicing of NTRK1 mRNA, leading to introduction of a premature termination codon. An NTRK1 autophosphorylation assay showed that c.1786G>A (p.Asp596Asn) abolished autophosphorylation of NTRK1. In addition, Western blotting showed that c.704C>G (p.Ser235*) and c.2350_2363del (p.Leu784Serfs*79) blunted NTRK1 expression to undetectable levels. The four novel NTRK1 mutations we report here will expand the repertoire of NTRK1 mutations in CIPA patients, and further our understanding of CIPA pathogenesis.

The Overlap between Fibromyalgia Syndrome and Myotonia Congenita.

BACKGROUND: Fibromyalgia syndrome (FMS) is a complex disorder characterized by chronic widespread pain (CWP), multiple areas of tenderness, sleep disturbance, fatigue, and mood or cognitive dysfunction. Myotonia congenita (MC) is an inherited myopathic disorder that is caused by mutations in the gene encoding the skeletal muscle chloride channel, which can infrequently manifest as generalized muscle cramps or myalgia. CASE REPORT: The first case was a 33-year-old woman who complained of CWP and chronic headache occurring during pregnancy, and the second case was a 37-year-old man with CWP and depression who suffered from cold-induced muscle cramps. These two patients were initially diagnosed with FMS by rheumatologists, based on CWP of longer than 3 months duration and mechanical tenderness in specific body regions. However, these two FMS patients were subsequently also diagnosed with MC. CONCLUSIONS: These two cases are the first report of an overlap of CWP between FMS and MC.

Identification of a novel nonsense mutation in the rod domain of GFAP that is associated with Alexander disease.

Alexander disease (AxD) is an astrogliopathy that primarily affects the white matter of the central nervous system (CNS). AxD is caused by mutations in a gene encoding GFAP (glial fibrillary acidic protein). The GFAP mutations in AxD have been reported to act in a gain-of-function manner partly because the identified mutations generate practically full-length GFAP. We found a novel nonsense mutation (c.1000 G>T, p.(Glu312Ter); also termed p.(E312*)) within a rod domain of GFAP in a 67-year-old Korean man with a history of memory impairment and leukoencephalopathy. This mutation, GFAP p.(E312*), removes part of the 2B rod domain and the whole tail domain from the GFAP. We characterized GFAP p.(E312*) using western blotting, in vitro assembly and sedimentation assay, and transient transfection of human adrenal cortex carcinoma SW13 (Vim(+)) cells with plasmids encoding GFAP p.(E312*). The GFAP p.(E312*) protein, either alone or in combination with wild-type GFAP, elicited self-aggregation. In addition, the assembled GFAP p.(E312*) aggregated into paracrystal-like structures, and GFAP p.(E312*) elicited more GFAP aggregation than wild-type GFAP in the human adrenal cortex carcinoma SW13 (Vim(+)) cells. Our findings are the first report, to the best of our knowledge, on this novel nonsense mutation of GFAP that is associated with AxD and paracrystal formation.

Effects of Flavonoid Compounds on ß-amyloid-peptide-induced Neuronal Death in Cultured Mouse Cortical Neurons.

Excessive accumulation of ß-amyloid peptide (Aß) is one of the major mechanisms responsible for neuronal death in Alzheimer's disease. Flavonoids, primarily antioxidants, are a group of polyphenolic compounds synthesized in plant cells. The present study aimed to identify flavonoid compounds that could inhibit Aß-induced neuronal death by examining the effects of various flavonoids on the neurotoxicity of Aß fragment 25-35 (Aß25-35) in mouse cortical cultures. Aß25-35 induced concentration- and exposure-time-dependent neuronal death. Neuronal death induced by 20 µM Aß25-35 was significantly inhibited by treatment with either Trolox or ascorbic acid. Among 10 flavonoid compounds tested [apigenin, baicalein, catechin, epicatechin, epigallocatechin gallate (EGCG), kaempferol, luteolin, myricetin, quercetin, and rutin], all except apigenin showed strong 1,1-diphenyl-2-pycrylhydrazyl (DPPH) scavenging activity under cell-free conditions. The flavonoid compounds except apigenin at a concentration of 30 µM also significantly inhibited neuronal death induced by 20 µM Aß25-35 at the end of 24 hours of exposure. Epicatechin, EGCG, luteolin, and myricetin showed more potent and persistent neuroprotective action than did the other compounds. These results demonstrated that oxidative stress was involved in Aß-induced neuronal death, and antioxidative flavonoid compounds, especially epicatechin, EGCG, luteolin, and myricetin, could inhibit neuronal death. These findings suggest that these four compounds may be developed as neuroprotective agents against Alzheimer's disease.

Preoperative pulmonary function is strongly related to myasthenic crisis after thymectomy.

BACKGROUND: Myasthenic crisis can be occasionally a complication after surgery for thymomatous myasthenia gravis (T-MG). AIMS: The purpose of this study was to investigate the influence of thymectomy on the subsequent clinical course of T-MG. STUDY DESIGN: Retrospective study. MATERIALS AND METHODS: Only T-MG patients with at least 36 months of follow-up after transsternal thymectomy for thymoma was screened, and those with successfully weaned from a ventilator after surgery were included in the study. RESULTS: Forty-eight T-MG patients were enrolled during the study period. Myasthenic crisis after thymectomy (MCAT) occurred in 12 (25%) patients with T-MG. Eight (67%) patients with MCAT experienced respiratory failure within the first 1 and 2 years after disease onset. The ratio of measured forced vital capacity (mFVC) to the predicted FVC (pFVC) preoperatively was the only independent factor affecting the occurrence of MCAT (odds ratio, 0.916; 95% confidence interval [CI], 0.867-0.967; P = 0.002). The area under the curve of the receiver operating characteristic for mFVC/pFVC was 0.881 (95% CI 0.754-0.956, P < 0.001), with sensitivity, specificity, and positive and negative predictive values of 58.3%, 97.2%, 87.5%, and 90%, respectively, at a threshold of ≤65% of mFVC/pFVC. CONCLUSIONS: MCAT may occur in patients with T-MG after thymectomy especially within 2 years after disease onset. Preoperative mFVC/pFVC is strongly associated with the occurrence of MCAT postoperatively.

Adenosine deaminase activity in cerebrospinal fluid and serum for the diagnosis of tuberculous meningitis.

OBJECTIVE: To evaluate the usefulness of serum and CSF adenosine deaminase (ADA) activity for the diagnosis of tuberculous meningitis (TBM) from other meningitis. METHODS: We studied CSF and serum ADA activity for 83 cases of TBM, 148 of bacterial meningitis (BM), and 262 of viral or aseptic meningitis. RESULTS: The mean ADA activities (IU/L) in CSF and serum were higher in TBM (11.80 ± 2.50, 30.28 ± 7.30) than in other types of meningitis (8.52 ± 3.60, 17.90 ± 9.20 in BM; 5.26 ± 1.90, 8.56 ± 5.9 in viral or aseptic meningitis). When we accepted a serum ADA activity cut-off value of 15 IU/L for the differential diagnosis of TBM and non-TBM with ROC analysis, the sensitivity was 84% and specificity was 82%. Combining CSF (≥ 10) and serum (≥ 15) ADA activity significantly increased overall specificity from 92% to 97% for the diagnosis of TBM. CONCLUSIONS: The determination of CSF and serum ADA activity is a simple and reliable test for differentiating TBM from other types of meningitis.

Cyp1a reporter zebrafish reveals target tissues for dioxin.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is the unintentional byproduct of various industrial processes, is classified as human carcinogen and could disrupt reproductive, developmental and endocrine systems. Induction of cyp1a1 is used as an indicator of TCDD exposure. We sought to determine tissues that are vulnerable to TCDD toxicity using a transgenic zebrafish (Danio rerio) model. We inserted a nuclear enhanced green fluorescent protein gene (EGFP) into the start codon of a zebrafish cyp1a gene in a fosmid clone using DNA recombineering. The resulting recombineered fosmid was then used to generate cyp1a reporter zebrafish, embryos of which were exposed to TCDD. Expression pattern of EGFP in the reporter zebrafish mirrored that of endogenous cyp1a mRNA. In addition, exposure of the embryos to TCDD at as low as 10 pM for 72 h, which does not elicit morphological abnormalities of embryos, markedly increased GFP expression. Furthermore, the reporter embryos responded to other AhR ligands as well. Exposure of the embryos to TCDD revealed previously reported (the cardiovascular system, liver, pancreas, kidney, swim bladder and skin) and unreported target tissues (retinal bipolar cells, otic vesicle, lateral line, cloaca and pectoral fin bud) for TCDD. Transgenic cyp1a reporter zebrafish we have developed can further understanding of ecotoxicological relevance and human health risks by TCDD. In addition, they could be used to identify agonists of AhR and antidotes to TCDD toxicity.

Acute inflammatory demyelinating polyradiculoneuropathy in a patient receiving oxaliplatin-based chemotherapy.

We report a case of acute inflammatory demyelinating polyradiculoneuropathy (AIDP) that developed in a patient with cholangiocarcinoma after receiving oxaliplatin-based chemotherapy. A 62-year-old man had multiple hypodense lesions with delayed enhancement in the both lobes of the liver on abdominal computed tomography. He was treated with 5-fluorouracil, leucovorin and oxaliplatin (100 mg/m(2)). After eight cycles of treatment and a cumulative oxaliplatin dose of 780 mg/m(2), he developed an unsteady gait, dysphagia, weakness of both the upper and lower limbs and impairment of all sensory modalities. Nerve conduction studies confirmed the diagnosis of AIDP. Immunoglobulin G i.v. was administered for 5 days but the neurological deficits of both his upper and lower limbs did not improve. This case highlights unusual peripheral nervous system manifestations in a patient who received chemotherapy with oxaliplatin.

Glioblastoma mimicking herpes simplex encephalitis.

We report a case of 70-year-old man with glioblastoma presenting as acute encephalitic illness. The patient exhibited sudden onset of cognitive impairment and headache for 2 days. Initial brain MRI showed left temporal lobe hyperintensity, and cerebrospinal fluid cytology revealed a mild pleocytosis. The patient had initially improved after medical treatment with a presumptive diagnosis of herpes simplex encephalitis (HSE). After 8 months, the patient complained of recurrent seizures. A follow-up brain MRI revealed marked increases in size and surrounding perilesional edema in the left temporal lesion on T2-weighted images and a new contrast-enhancing lesion on gadolinium-enhanced T1-weighted images. Stereotactic brain biopsy revealed a glioblastoma. The atypical encephalitic presentation of glioblastoma should be considered if definitive evidence for the diagnosis of HSE cannot be obtained.

White matter hyperintensity as a factor associated with delayed mood disorders in patients with acute ischemic stroke.

BACKGROUND: Mood disorder is a frequent complication of stroke. Comorbid depressive and anxiety disorders are very common, indicating that it is advisable to assess both disorders at the same time. The aim of the present study was to examine the prevalence of post-stroke depression (PSD) and poststroke anxiety (PSA) at baseline and to evaluate factors related to delayed PSD and PSA at 3 months after stroke onset. METHODS: This was a prospectively registered and retrospectively analyzed study of patients with acute ischemic stroke between January 2009 and March 2010. Patients included in this study were interviewed in order to evaluate their Hospital Anxiety and Depression Scale (HADS) scores. In this study, each depression and anxiety score was dichotomized into 'nondepressive and nonanxious' (HADS-D and HADS-A ≤7) and 'depressive and anxious' (HADS-D and HADS-A >7). Multiple logistic regression analysis was used to evaluate the independent factors of depressive and anxious symptoms 3 months after stroke onset. RESULTS: Of the 133 patients, 47.4% were 'depressive' and 56.4% were 'anxious' at baseline. The depressive and anxious groups had a significantly higher frequency of severe white matter hyperintensity (WMH) than the nondepressive and nonanxious groups (p < 0.05). The independent factors of PSD and PSA at 3 months were deep white matter hyperintensities (DWMH) and modified Rankin scale 0 to 1 at 3 months. CONCLUSION: In conclusions, the results of our study demonstrated that delayed depression and anxiety after ischemic stroke were related to the severity of DWMH and unfavorable outcomes at 3 months, regardless of anti-anxiety treatment. Our results suggested that WMH might be associated with pathomechanism of delayed depression and anxiety.

Clinical characteristics and predictive factors of myasthenic crisis after thymectomy.

The aims of this study were to assess the clinical characteristics of myasthenic crisis after thymectomy (MCAT) and to identify predictors affecting the occurrence of MCAT. Of 66 patients with myasthenia gravis (MG), MCAT occurred in 20 patients (30.3%). The median time interval from thymectomy to MCAT was 3.4 months. MCAT occurred in 65.0% of patients within the first 6 months of a thymectomy, and 35.0% after 6 months. A second MCAT occurred in nine (45.0%) patients who survived the first MCAT, and in seven (50.0%) of 14 patients with a history of a preoperative myasthenic crisis before thymectomy (MCBT). A history of MCBT, and clinical factors reflecting perioperative clinical severity at thymectomy, including preoperative Osserman's grade, bulbar symptoms, use of immunosuppressants, pulmonary function, and postoperative delayed ventilator weaning, were significantly correlated with the occurrence of MCAT on univariate analysis. However, a history of MCBT was the only independent factor affecting the occurrence of MCAT on multivariate logistic regression analysis (odds ratio, 17.9; 95% confidence interval, 4.019-79.873; p<0.001). Thus, the occurrence of MCAT may be correlated only with a history of MCBT rather than with factors reflecting perioperative clinical severity. MG patients with a history of MCBT are more susceptible to MCAT, particularly within the first 6 months of thymectomy.

High cleavage efficiency of a 2A peptide derived from porcine teschovirus-1 in human cell lines, zebrafish and mice.

When expression of more than one gene is required in cells, bicistronic or multicistronic expression vectors have been used. Among various strategies employed to construct bicistronic or multicistronic vectors, an internal ribosomal entry site (IRES) has been widely used. Due to the large size and difference in expression levels between genes before and after IRES, however, a new strategy was required to replace IRES. A self-cleaving 2A peptide could be a good candidate to replace IRES because of its small size and high cleavage efficiency between genes upstream and downstream of the 2A peptide. Despite the advantages of the 2A peptides, its use is not widespread because (i) there are no publicly available cloning vectors harboring a 2A peptide gene and (ii) comprehensive comparison of cleavage efficiency among various 2A peptides reported to date has not been performed in different contexts. Here, we generated four expression plasmids each harboring different 2A peptides derived from the foot-and-mouth disease virus, equine rhinitis A virus, Thosea asigna virus and porcine teschovirus-1, respectively, and evaluated their cleavage efficiency in three commonly used human cell lines, zebrafish embryos and adult mice. Western blotting and confocal microscopic analyses revealed that among the four 2As, the one derived from porcine teschovirus-1 (P2A) has the highest cleavage efficiency in all the contexts examined. We anticipate that the 2A-harboring cloning vectors we generated and the highest efficiency of the P2A peptide we demonstrated would help biomedical researchers easily adopt the 2A technology when bicistronic or multicistronic expression is required.

Increased expression of L-amino acid transporters in balloon cells of tuberous sclerosis.

OBJECTS: Tuberous sclerosis complex (TSC) is a dysgenetic syndrome involved in multiple organs, and the pathognomonic cortical tuber act as an epileptic substrate. The amino acid transport system L (LAT) is a major nutrient transport system, and LAT1 is highly expressed in malignant tumors to support tumor cell growth. To study the life-long epilepsy from the cortical tuber, the expression of LAT1 in balloon cells and dysplastic neurons of the cortical tuber is investigated. MATERIALS AND METHODS: LAT1 expression was investigated by LAT1 mRNA using reverse transcription-polymerase chain reaction and immunohistochemical staining with anti-human LAT1 antibody in nine patients with TSC and three control brains. CONCLUSION: LAT1 mRNA was detectable only in fresh-frozen tissues of TSC, and it was upregulated in the cortical tuber lesion. While the LAT1 immunopositivity of control brains was limited in the capillary endothelial cells in the gray matter, increased LAT1 immunopositivity was noted in balloon cells of the cortical tubers in addition to the capillary endothelial cells as shown in control brains. Linear and strong immunopositivity along the cell membrane and cytoplasm of the balloon cells, and weakly granular immunopositivity in their cytoplasm were noted. Increased expression of LAT1 in the balloon cells is important for the active transport of large neutral amino acids into the balloon cells, and that the biologic process may play an important role in the active protein synthesis with metabolic maintenance of balloon cells in cortical tubers of patients with TSC.

Cerebral embolism of iodized oil (lipiodol) after transcatheter arterial chemoembolization for hepatocellular carcinoma.

Cerebral lipiodol embolism is a rare complication of transcatheter arterial chemoembolization (TACE). Its pathological mechanism remains ambiguous despite several investigations. In Case 1, a 67-year-old man with hepatocellular carcinoma (HCC) experienced neurological deficits soon after undergoing a fourth session of TACE. Computed tomography (CT) scan showed multiple hyperdense lesions along the gyrus of frontal lobes and in the subcortical white matter. Transcranial Doppler (TCD) and transesophageal echocardiogram performed during the intravenous injection of agitated saline documented the presence of a right-to-left shunt (RLS) by demonstrating microbubbles in the left middle cerebral artery and left atrium. In Case 2, a 63-year-old woman underwent a third TACE due to a large HCC. After the procedure, her mental status deteriorated. Brain CT showed multiple hyperdense lesions on the cerebral and cerebellar cortex. TCD with agitated saline showed multiple microembolic signals shortly after the injection of agitated saline. The risk of cerebral lipiodol embolism may increase with recurrence and progression of HCC in patients who have a pre-existing RLS in the heart or lung. A test for the detection of an RLS may be necessary to identify patients with a heightened risk of cerebral embolism when multiple TACE procedures are required. TACE for HCC can cause pulmonary embolism or infarction.(1,2) However, cerebral lipiodol embolism is rare after TACE. There have been several reports of cerebral embolism after TACE, but their exact mechanism has not yet been fully elucidated. We report herein 2 patients who developed cerebral lipiodol embolism after undergoing multiple TACE procedures for remnant HCC through a pre-existing RLS.

Phosphodiesterase 4D gene and risk of noncardiogenic ischemic stroke in a Korean population.

Recently published studies from different populations provide apparently conflicting evidence on the association between the phosphodiesterase 4D (PDE4D) gene and ischemic stroke. The relationship between a representative PDE4D genotype and ischemic stroke was explored in a case-control study of 205 consecutive Korean patients with noncardiogenic ischemic stroke and 103 healthy controls who were neurologically and radiologically proven to be stroke-free. We selected and genotyped a PDE4D single nucleotide polymorphism (SNP 41, rs152312) as a candidate marker for susceptibility to ischemic stroke because SNP 41 has shown the most significant association with stroke in both a meta-analysis and the original Icelandic study of the PDE4D gene. No significant difference was observed between the cases and controls in the distribution of the PDE4D SNP 41 genotypes. The results from the adjusted conditional logistic regression analysis (adjusted for age, hypertension, diabetes and smoking status) showed no significant association between PDE4D SNP 41 genotypes and an increased risk of noncardiogenic ischemic stroke. The PDE4D gene is not a major risk factor for noncardiogenic ischemic stroke in a Korean population, which supports the recent evidence suggesting that the causative genetic variants of ischemic stroke may differ across populations.