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Shimizu K.,Shinshu University | Shimizu K.,Saitama Childrens Medical Center | Wakui K.,Shinshu University | Kosho T.,Shinshu University | And 14 more authors.
American Journal of Medical Genetics, Part A

Wolf-Hirschhorn syndrome (WHS) is a contiguous gene deletion syndrome of the distal 4p chromosome, characterized by craniofacial features, growth impairment, intellectual disability, and seizures. Although genotype-phenotype correlation studies have previously been published, several important issues remain to be elucidated including seizure severity. We present detailed clinical and molecular-cytogenetic findings from a microarray and fluorescence in situ hybridization (FISH)-based genotype-phenotype analysis of 22 Japanese WHS patients, the first large non-Western series. 4p deletions were terminal in 20 patients and interstitial in two, with deletion sizes ranging from 2.06 to 29.42Mb. The new Wolf-Hirschhorn syndrome critical region (WHSCR2) was deleted in all cases, and duplication of other chromosomal regions occurred in four. Complex mosaicism was identified in two cases: two different 4p terminal deletions; a simple 4p terminal deletion and an unbalanced translocation with the same 4p breakpoint. Seizures began in infancy in 33% (2/6) of cases with small (<6Mb) deletions and in 86% (12/14) of cases with larger deletions (>6Mb). Status epilepticus occurred in 17% (1/6) with small deletions and in 87% (13/15) with larger deletions. Renal hypoplasia or dysplasia and structural ocular anomalies were more prevalent in those with larger deletions. A new susceptible region for seizure occurrence is suggested between 0.76 and 1.3Mb from 4pter, encompassing CTBP1 and CPLX1, and distal to the previously-supposed candidate gene LETM1. The usefulness of bromide therapy for seizures and additional clinical features including hypercholesterolemia are also described. © 2013 Wiley Periodicals, Inc. Source

Hisaoka K.,Institute for Clinical Research | Hisaoka K.,Hiroshima University | Tsuchioka M.,Institute for Clinical Research | Yano R.,Institute for Clinical Research | And 8 more authors.
Journal of Biological Chemistry

Recently, both clinical and animal studies demonstrated neuronal and glial plasticity to be important for the therapeutic action of antidepressants. Antidepressants increase glial cell line-derived neurotrophic factor (GDNF) production through monoamine-independent protein-tyrosine kinase, extracellular signal-regulated kinase (ERK), and cAMP responsive element-binding protein (CREB) activation in glial cells (Hisaoka, K., Takebayashi, M., Tsuchioka, M., Maeda, N., Nakata, Y., and Yamawaki, S. (2007) J. Pharmacol. Exp. Ther. 321, 148-157; Hisaoka, K., Maeda, N., Tsuchioka, M., and Takebayashi, M. (2008) Brain Res. 1196, 53-58). This study clarifies the type of tyrosine kinase and mechanism of antidepressant-induced GDNF production in C6 glioma cells and normal human astrocytes. The amitriptyline (a tricyclic antidepressant)-induced ERK activation was specifically and completely inhibited by fibroblast growth factor receptor (FGFR) tyrosine kinase inhibitors and siRNA for FGFR1 and -2. Treatment with amitriptyline or several different classes of antidepressants, but not non-antidepressants, acutely increased the phosphorylation of FGFRs and FGFR substrate 2α (FRS2α). Amitriptyline-induced CREB phosphorylation and GDNF production were blocked by FGFR-tyrosine kinase inhibitors. Therefore, antidepressants activate the FGFR/FRS2α/ERK/CREB signaling cascade, thus resulting in GDNF production. Furthermore, we attempted to elucidate how antidepressants activate FGFR signaling. The effect of amitriptyline was inhibited by heparin, non-permeant FGF-2 neutralizing antibodies, and matrix metalloproteinase (MMP) inhibitors. Serotonin (5-HT) also increased GDNF production through FGFR2 (Tsuchioka, M., Takebayashi, M., Hisaoka, K., Maeda, N., and Nakata, Y. (2008) J. Neurochem. 106, 244-257); however, the effect of 5-HT was not inhibited by heparin and MMP inhibitors. These results suggest that amitriptyline-induced FGFR activation might occur through an extracellular pathway, in contrast to that of 5-HT. The current data show that amitriptyline-induced FGFR activation might occur by the MMP-dependent shedding of FGFR ligands, such as FGF-2, thus resulting in GDNF production. © 2011 by The American Society for Biochemistry and Molecular Biology, Inc. Source

Shibasaki C.,Institute for Clinical Research | Takebayashi M.,Institute for Clinical Research | Takebayashi M.,Kure Medical Center and Chugoku Cancer Center | Fujita Y.,Institute for Clinical Research | Yamawaki S.,Hiroshima University
Neuropsychiatric Disease and Treatment

Purpose: Electroconvulsive therapy (ECT) is an effective treatment for depression and schizophrenia. However, there is a high rate of relapse after an initial response to ECT, even with antidepressant or antipsychotic maintenance therapy. This study was carried out to examine the factors that influence the risk of relapse in schizophrenic patients after a response to ECT.Patients and methods: We retrospectively reviewed the records of 43 patients with schizophrenia who received and responded to an acute ECT course. We analyzed the associated clinical variables and relapse after response to the acute ECT. Relapse was defined as a Clinical Global Impressions Improvement score 6 or a psychiatric rehospitalization.Results: All patients were treated with neuroleptic medication after the acute ECT course. The relapse-free rate of all 43 patients at 1 year was 57.3%, and the median relapse-free period was 21.5 months. Multivariate analysis showed that the number of ECT sessions was associated with a significant increase in the risk of relapse (hazard ratio: 1.159; P=0.033). Patients who were treated with adjunctive mood stabilizers as maintenance pharmacotherapy after the response to the acute ECT course were at a lower risk of relapse than were those treated without mood stabilizers (hazard ratio: 0.257; P=0.047).Conclusion: Our study on the recurrence of schizophrenia after a response to an acute ECT course suggests that the number of ECT sessions might be related to the risk of relapse and that adjunctive mood stabilizers might be effective in preventing relapse. © 2015 Shibasaki et al. Source

Nitta H.,Hiroshima University | Harada Y.,Hiroshima University | Okikawa Y.,Kure Medical Center and Chugoku Cancer Center | Fujii M.,Hiroshima University | And 3 more authors.
Internal Medicine

We report a case of Good's syndrome-associated pure red cell aplasia (PRCA) with myelodysplastic syndrome (MDS). In this case, effector memory T (T EM) cells were expanded in the bone marrow. It remains uncertain whether the development of MDS was caused by the basic marrow defects or radiation therapy. However, since CD8 + perforin + T EM cells expanded in the bone marrow, as was previously described for 3 of our patients with thymoma-associated PRCA, it is highly possible that the pathogenic mechanism of PRCA that is accompanied by thymoma is related to the expanded CD8 + perforin + T EM cells in this MDS-complicated case. © 2011 The Japanese Society of Internal Medicine. Source

Tsuchioka M.,Institute for Clinical Research | Hisaoka K.,Hiroshima University | Yano R.,Institute for Clinical Research | Yano R.,Hiroshima University | And 6 more authors.
Brain Research

Riluzole is approved for the treatment of amyotrophic lateral sclerosis (ALS); however, recent accumulating evidence suggests that riluzole is also effective for the treatment of psychiatric disorders, such as mood disorders. Plastic change in the brain induced by neurotrophic factors/growth factors is thought to be involved in the mechanism of antidepressants. This study investigated the mechanism of riluzole-induced glial cell line-derived neurotrophic factor (GDNF) production in rat C6 glioma cells (C6 cells), a model of astrocytes. The study investigated the phosphorylation of cAMP response element binding protein (CREB), an important transcriptional factor of the gdnf gene, and found that riluzole increased CREB phosphorylation in a time-dependent manner, peaking at 40 min after treatment. The riluzole-induced CREB phosphorylation was completely blocked by a mitogen-activated protein kinase kinase (MEK) inhibitor (U0126). Riluzole increased extracellular signal-regulated kinase (ERK) activation prior to CREB phosphorylation. These results suggest that riluzole rapidly activates the MEK/ERK/CREB pathway. Furthermore, two types of fibroblast growth factor receptor (FGFR) tyrosine kinase inhibitors (SU5402 and PD173074) completely blocked riluzole-induced CREB phosphorylation. In addition, riluzole rapidly phosphorylated FGFR substrate 2α (FRS2α), a major adaptor protein of FGFR. These findings suggest that riluzole induces CREB phosphorylation through FGFR. In addition, PD173074 inhibited riluzole-induced GDNF production. In contrast, l-glutamate and a glutamate transporter inhibitor (t-PDC) did not yield any effects in either CREB phosphorylation or GDNF production. These findings suggest that riluzole rapidly activates a MEK/ERK/CREB pathway through FGFR in a glutamate transporter-independent manner, followed by GDNF expression in C6 cells. © 2011 Elsevier B.V. All rights reserved. Source

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