Publications by authors named "Takahiro Iizuka"

Background And Objectives: Anti-alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor (anti-AMPAR) encephalitis manifests as limbic encephalitis in adults and is often associated with cancer. Although some reports suggest that it may occur in children, the clinical features in this population, as well as the prognostic factors and long-term outcomes in children and adults, are unknown.

Methods: We performed a retrospective, international collaborative study of patients with anti-AMPAR encephalitis.

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Background: Catatonia is a psychomotor disorder characterized by diverse clinical features, including mutism, stereotypy, posturing, waxy flexibility, and echophenomena. This condition is often observed in patients with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis, in which impaired glutamatergic transmission through antibody-mediated NMDAR internalization is demonstrated. However, cases of anti-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) encephalitis presenting as catatonia have rarely been reported, and the mechanisms underlying such presentation remain unclear.

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Anti-NMDA receptor (NMDAR) encephalitis is a devastating disease with severe psychiatric and neurological symptoms believed to be caused by pathogenic autoantibodies that bind to the N-terminal domain (NTD) of the NMDAR GluN1 subunit (GluN1-NTD) crosslinking adjacent NMDARs and driving their internalization. Here we describe ART5803, a humanized monovalent antibody, as a potential therapy for anti-NMDAR encephalitis. ART5803 binds with a high affinity (K = 0.

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Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is an autoimmune disorder characterized by psychiatric symptoms, seizures, and dyskinesias. This case report describes a 30-year-old woman who was initially suspected of having a somatic symptom disorder because of the development of seizures mimicking psychogenic non-epileptic seizures (PNES). At presentation, she was able to engage in conversation and follow instructions, but exhibited slight fever, sensory abnormalities, and non-stereotypical seizures.

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To explore the potential efficacy of early initiation of intravenous cyclophosphamide (IVCPA), we reviewed consecutive four cases of super-refractory cryptogenic-new onset refractory status epilepticus (C-NORSE) between 2015 and 2023. We compared functional outcomes at 3 months and 1 year after the onset between patients who received IVCPA within 20 days (early-treated) and those who received it later (late-treated). All patients (median age: 43 years) had a prodromal fever.

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Introduction: Anti-NMDA receptor encephalitis is an autoimmune disorder caused by autoantibodies (abs) against the conformational epitope on GluN1 subunits. GluN1-abs have been determined with cell-based assay (CBA) co-expressing GluN1/GluN2 subunits. However, commercial fixed CBA expressing only GluN1 subunit has increasingly been used in clinical practice.

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A 35-year-old woman with no prior history of epilepsy developed status epilepticus (SE), which was highly resistant to multiple antiseizure medications and sedatives. The etiology of SE was not identified despite extensive investigation, and the patient was diagnosed with cryptogenic new-onset refractory status epilepticus (C-NORSE). Although first-line immunotherapies such as high-dose corticosteroids and plasma exchange were ineffective, the patient manifested a resolution of SE after the administration of tocilizumab, which inhibits interleukin-6.

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Objectives: To assess the daily function of children with anti-N-methyl-d-aspartate receptor encephalitis (NMDARe) after a minimal follow-up of 5 years.

Methods: Patients 18 years and younger by the time of disease onset, whose serum and CSF were studied in our center between 2013 and 2017, were included in the study. Patients' daily life function was assessed by their physicians using a 15-domain question format (Liverpool Outcome Score).

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One characteristic of migraine is recurrent headache attacks, which are known to be induced by changes in climatic variables such as atmospheric pressure, humidity, and outside temperature. However, the relationship between temperature changes and migraine remains unclear. Therefore, we investigated the relationship between body temperature changes and cortical spreading depression (CSD) using KCl-induced rat models of CSD.

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Hybrid lethality, a type of postzygotic reproductive isolation, is an obstacle to wide hybridization breeding. Here, we report the hybrid lethality that was observed in crosses between the cultivated tobacco, (section ), and the wild tobacco species, (section ). Reciprocal hybrid seedlings were inviable at 28 °C, and the lethality was characterized by browning of the hypocotyl and roots, suggesting that hybrid lethality is due to the interaction of nuclear genomes derived from each parental species, and not to a cytoplasmic effect.

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Background And Objectives: To elucidate current epidemiologic, clinical, and immunologic profiles and treatments of stiff-person syndrome (SPS) in Japan.

Methods: A nationwide mail survey was conducted using an established method. Data processing sheets were sent to randomly selected departments of internal medicine, neurology, pediatrics, psychiatry, and neurosurgery in hospitals and clinics throughout Japan to identify patients with SPS who were seen between January 2015 and December 2017.

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We herein report a case of anti-gamma aminobutyric acid type A receptor antibody-associated encephalitis (anti-GABA-RE) with progressive aphasia and generalized tonic-clonic seizures. Cerebral magnetic resonance imaging (MRI) showed cortical brain lesions coupled with hypermetabolism on fluorodeoxyglucose-positron emission tomography. After two courses of methylprednisolone pulse therapy, improvements in neurological symptoms without sequelae and the total disappearance of MRI lesions were observed.

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A variety of neuronal surface (NS) antibodies (NS-Ab) have been identified in autoimmune encephalitis (AE). Tissue-based assay (TBA) using a rodent brain immunohistochemistry (IHC) is used to screen NS-Ab, while cell-based assay (CBA) to determine NS antigens. Commercial rat brain IHC is currently available but its clinical relevance remains unclear.

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Cryptogenic new-onset refractory status epilepticus (C-NORSE) is a neurologic emergency condition characterized by refractory status epilepticus (RSE) of unknown cause. Brain atrophy in a setting of C-NORSE is usually irreversible. A 33-year-old woman who was highly suspected of C-NORSE once showed mild frontotemporal atrophy on brain magnetic resonance imaging (MRI), but follow-up MRI revealed recovery of the brain atrophy.

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We report an autopsy case of anti-N-methyl-D-aspartate (NMDA) receptor (NMDAR) encephalitis with concurrent human herpes virus-6 (HHV-6) A deoxyribonucleic acid (DNA) detection in cerebrospinal fluid (CSF). A 38-year-old previously healthy Japanese man presented with a generalized seizure. Brain magnetic resonance imaging (MRI) findings were unremarkable, but CSF revealed pleocytosis.

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Article Synopsis
  • - Paraneoplastic cerebellar degeneration (PCD) is marked by the loss of Purkinje cells and can be linked to autoantibodies against neuronal antigens like Yo and P/Q-type calcium channels; however, the specific immune mechanisms for P/Q-VGCC remain unclear.
  • - In this study, researchers examined brain tissues from PCD cases with anti-P/Q-VGCC and anti-Yo autoantibodies to identify differences in neuropathological features, such as cell loss patterns and inflammatory responses.
  • - Findings showed that anti-Yo-PCD resulted in widespread Purkinje cell loss and significant immune cell involvement, while anti-P/Q-VGCC-PCD had focal cell loss and less inflammation
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Anti-N-methyl-D-aspartate receptor (NMDAR) antibody encephalitis is caused by a reversible inhibition of ion channel actions by autoantibodies and is associated with a relatively good prognosis. Pathological findings of NMDAR encephalitis usually do not show neurophagorous nodules, but rare or mild inflammatory infiltration. We report a patient of small cell lung cancer (SCLC)-related paraneoplastic encephalitis with NMDAR antibodies, a cytotoxic T-cell-mediated pathology of the brain, and a rapid clinical course.

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Progressive encephalomyelitis with rigidity and myoclonus (PERM) is a severe form of stiff-person spectrum disorder. We report a 59-year-old man who presented with progressive encephalomyelitis causing diplopia, bulbar palsy, severe dysautonomia, followed by stiffness and myoclonic cluster. Laboratory tests showed mild pleocytosis, with markedly elevated plasma levels of norepinephrine, epinephrine, and arginine vasopressin.

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Objectives: Status epilepticus (SE) can be associated with neuronal surface antibodies (NS-Abs) but NS-Ab detection rate remains unknown in patients with SE of unclear etiology at symptom presentation but suspected of having an autoimmune etiology (SE suspected autoimmune). We aimed to determine the NS-Ab detection rate and the clinical features that predict the presence of NS-Abs in patients with SE suspected autoimmune.

Methods: We retrospectively reviewed the clinical information of 137 patients with SE suspected autoimmune who underwent testing for NS-Abs between January 2007 and September 2020.

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Hybrid lethality, meaning the death of F hybrid seedlings, has been observed in many plant species, including Nicotiana. Previously, we have revealed that hybrids of the selected Nicotiana occidentalis accession and N. tabacum, an allotetraploid with S and T genomes, exhibited lethality characterized by the fading of shoot color.

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Progressive encephalomyelitis with rigidity and myoclonus (PERM) is a severe form of stiff-person spectrum disorder characterized by painful spasms, myoclonic jerks, hyperekplexia, brainstem dysfunction, and dysautonomia, which is sometimes resistant to γ-amino-butyric acid (GABA)-ergic agents. The response to immunotherapy varies depending on identified autoantibodies. We report a dramatic response to dexmedetomidine in a patient with glycine receptor (GlyR) antibody-positive PERM who developed intractable clusters of myoclonic jerks and paroxysmal sympathetic hyperactivity (PSH) that was highly refractory to conventional symptomatic treatment with GABAergic drugs and immunotherapy.

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Objective: To report the clinical, neuroimaging, and antibody associations in patients with autoimmune encephalitis (AE) and thymoma.

Methods: A retrospective cohort study of 43 patients was conducted. Antibody determination and immunoprecipitation to characterize novel antigens were performed using reported techniques.

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Anti-NMDA receptor (NMDAR) encephalitis is an autoimmune disease caused by autoantibodies against the extracellular conformational epitope of the NR1 subunit of the NMDAR (GluN1 antibodies). A series of autoantibodies directed against neuronal surface (NS) or synaptic proteins play an important role in the pathophysiological mechanisms of post-herpes simplex encephalitis (post-HSE), overlapping autoimmune encephalitis and demyelinating syndrome, epileptic seizures, psychosis, involuntary movements (orofacial and limb dyskinesias, catatonia, dystonia, chorea, myoclonus, psychogenic nonepileptic seizures, and faciobrachial dystonic seizures), postpartum psychosis, stiff-person spectrum disorder (including progressive encephalomyelitis with rigidity and myoclonus [PERM]), cerebellar ataxia, and sleep behavior disorders. These NS antibodies are identified with cell-based assays and immunohistochemistry using nonperfused paraformaldehyde-fixed rodent brain tissue.

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Background: Asymptomatic acute ischemic lesions (AIL) may be coincidentally found on brain magnetic resonance imaging (MRI) obtained during the acute phase of intracerebral hemorrhage, but its clinical significance has yet to be determined. The objective of this study is to determine the frequency of asymptomatic AIL, its characteristic features of brain MRI and risk factors in patients with acute intracerebral hemorrhage.

Methods: We retrospectively reviewed the clinical information of 108 patients with intracerebral hemorrhage who underwent brain MRIs within 30 days of hospitalization between April 2013 and January 2018.

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