Amyotrophic lateral sclerosis (ALS) is a devastating disorder characterized by degeneration of motor neurons of the primary motor cortex, brainstem and spinal cord. ALS patients die within 3 to 5 years without respiratory support. Detecting the causing gene is necessary to elucidate ALS.
We identified mutations of optineurin (OPTN) in ALS. We found three types of mutation of OPTN: a homozygous deletion of exon 5, a homozygous Q398X nonsense mutation and a heterozygous E478G missense mutation within its ubiquitin-binding domain. Cell transfection experiments showed that the nonsense and missense mutations of OPTN abolished the inhibition of activation of nuclear factor kappa B. The missense mutation revealed a cytoplasmic distribution different from that of the wild type.
A case with the E478G mutation showed OPTN-immunoreactive cytoplasmic retention, and Golgi fragmentation was identified in 70% of the anterior horn cells. TDP-43- or SOD1-positive inclusions of sporadic and SOD1 cases of ALS were also immunolabelled with anti-OPTN antibodies. Furthermore, optineurin is co-localized with fused in sarcoma (FUS) in basophilic inclusions of ALS with FUS mutation and in basophilic inclusion body disease.
Our findings suggest that OPTN is involved in the great part of pathogenesis of ALS.

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Bacterial meningitis and tubercular meningitis are still neurological emergencies characterized by severe mortality and morbidity. Recent studies of meta-analysis have shown the usefulness of cerebrospinal fluid (CSF) lactate and CSF adenosine deaminase (ADA) as markers for the detection of bacterial meningitis and tubercular meningitis, respectively. CSF lactate has a high sensitivity and specificity for the diagnosis of bacterial meningitis, but the sensitivity can be reduced by antibiotic pretreatment. CSF-ADA has a moderate sensitivity but a high specificity and is reliable for the diagnosis of tubercular meningitis. These old diagnostic markers can be evaluated in resource-poor settings including small general hospitals and non-specialized hospitals for infectious diseases, and they can contribute to the quick and accurate diagnosis of infectious meningitis.

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Community acquired bacterial meningitis due to extended spectrum β lactamase-producing Escherichia coli is very rare. We report the case of a 72-year-old woman being treated for longstanding diabetes mellitus. She developed lower back pain accompanied by elevated body temperature, and was transported to the emergency unit in our hospital five days later because of impaired consciousness. An abdominal plane CT showed acute pyelonephritis and a brain MRI showed inflammatory exudate in the posterior horn of her bilateral ventricles. A lumbar puncture was performed, and examination of the cerebrospinal fluid revealed a marked elevation in her cell count (polymorphonuclear leukocytes dominant) that we diagnosed as bacterial meningitis. Initially, she was treated with intravenous meropenem, ceftriaxon, and vancomycin. Extended spectrum β lactamase-producing Escherichia coli were then detected in her urinary and blood cultures, and the antibiotics were changed to intravenous meropenem, gentamicin, and intrathecal gentamicin. Her clinical symptoms improved, but her inflammatory reaction was prolonged and we detected spondylitis. She was then treated with levofloxacin, and the inflammatory reaction improved. Extended spectrum β lactamase-producing Escherichia coli should be taken into consideration as a cause of community acquired bacterial meningitis.

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A 65-year-old woman developed left optic neuritis during the course of peg-interferon alpha (PEG-IFN-α) and ribavirin combination therapy for chronic hepatitis C. Brain T₂W-MRI disclosed hyperintense lesions in the corpus callosum and white matter. We diagnosed neuromyelitis optica spectrum disorder (NMOSD) on the basis of anti-aquaporin-4 antibody seropositivity. PEG-IFN-α was discontinued, and she received steroid pulse therapy (intravenous high dose methylprednisolone). Two weeks later she also developed right optic neuritis. Repetitive steroid pulse therapy improved the left optic neuritis, but the upper half of the visual field of the right eye remained impaired. One month later she presented with mild dysarthria and mild left hemiparesis. Brain MRI disclosed an extensive pyramidal tract lesion from the right corona radiata to the pedunculus cerebri. This cerebral pyramidal tract lesion is associated with NMOSD. Our case corresponds to the past reports of optic neuritis or multiple sclerosis-like disease triggered by IFN-α. IFN-α may trigger NMOSD via a biological effect characteristic of Type I IFNs, a group that includes IFN-α and IFN-β.

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A 61-year-old Japanese female was admitted with sudden onset of choreic movements of the right extremities. MRI demonstrated no abnormality suggestive of acute infarcts. Cerebral angiography revealed high-grade stenosis of bilateral middle cerebral arteries at the origin and abnormal vascular network compatible with moyamoya disease. Administration of low-dose haloperidol rapidly resolved the choreic movements. SPECT obtained one month after the clinical onset demonstrated increase of the regional cerebral blood flow (rCBF) in the left basal ganglia. Moyamoya disease presenting chorea as its initial symptom was only infrequently reported in the elderly. In the present case, increased rCBF in the basal ganglia and remarkable effect of a dopamine D2 blocker suggest functional abnormality of the corresponding striatum as an underlying cause of hemichorea.

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A 29-year-old female developed diplopia, nasal voice and gait disturbance after an upper respiratory infection. On admission, she presented with bilateral external ophthalmoplegia, slight bilateral facial nerve palsy, dysarthria, dysphagia, cervical and brachial muscle weakness, ataxia and areflexia. She had serum anti-GT1a, anti-GQ1b and anti-galactocerebroside IgG antibodies. She was diagnosed with an overlap case of Fisher syndrome and pharyngeal-cervical-brachial variant of Guillain-Barré syndrome. Intravenous immunoglobulin therapy was effective for the ophthalmoplegia and ataxia, but did not improve the bilateral facial nerve palsy and brachial muscle weakness. The facial nerve palsy clearly worsened despite improvement in other symptoms, and therefore high-dose intravenous methylprednisolone therapy was added. The distinct response to treatment may be caused by different activity, production, clearance and reactivity to intravenous immunoglobulin of the autoantibodies. The present case suggests that treatment response and patterns of recovery differ according to the causative anti-ganglioside antibodies.

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A 74-year-old man complained of near loss of consciousness when he rotated his head to the left side. The symptom was reversed by returning his head to a neutral position. Transcranial Doppler studies with the patient's neck rotated into the left side revealed reduction of flow in his left vertebral artery. Vertebral angiography revealed a hypoplastic right vertebral artery and occlusion of the left vertebral artery at the C6 level on head rotation. We diagnosed him bow hunter's syndrome and treated him conservatively. Six months later, he was symptom-free on head rotation. Transcranial Doppler and vertebral angiography demonstrated the disappearance of the vertebral artery occlusion at the neck rotation.
Some patient without any definite cause can be treated conservatively, and surgical interventions for bow hunter's syndrome should be carefully decided.

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An 82-year-old man was suspected to have experienced a transient ischemic attack since he developed transient weakness in the right upper limb twice. On admission, neurologic examination yielded normal findings except for mild cognitive impairment. Brain CT and images showed an unexpected finding of acute focal subarachnoid hemorrhage in the left central sulcus, although MR angiography and venography did not show any abnormality. T₂^* weighted images showed superficial siderosis in the bilateral frontal lobes, which indicated the possibility of a recurrent subarachnoid hemorrhage. We propose that focal subarachnoid hemorrhage should be included in the differential diagnosis of transient ischemic attack.

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Reactive oxygen species (ROS) derived from mitochondria play an essential role in stroke as well as in neurodegenerative disorders. Although hyperglycemia associated with diabetes mellitus is well known to enhance ROS production in vascular endothelial cells, the effects of either acute or chronic high glucose environments on neurons and glial cells remain unclear. Astroglia play a pivotal role in glucose metabolism. Thus, the astroglial metabolic response to high glucose environments is an interesting subject. In particular, the glutathione/pentose phosphate pathway (PPP) system, which is a major defense mechanism against ROS in the brain, contributes to glucose metabolism and is more active in astroglia. We propose that high glucose environments activate PPP through an increased flux to the hexosamine biosynthetic pathway (HBP). HBP is known to induce endoplasmic reticulum (ER) stress under hyperglycemia, resulting in the nuclear translocation of nuclear factor-erythroid-2-related factor 2 (Nrf2), a master regulator of phase 2 detoxifying enzymes including glucose-6-phosphate dehydrogenase that regulates PPP activity, as Nrf2 is reported to be a direct substrate of protein kinase RNA (PKR)-like ER kinase (PERK), a transducer of ER stress. Therefore, the phosphorylation of Nrf2 by hyperglycemia-induced ER stress facilitates Nrf2 translocation through PERK, thus activating the PPP. If acute or chronic hyperglycemia induces PPP activation in astroglia to reduce ROS, reducing the glucose concentration may be accompanied by a risk, which may explain the lack of evidence that strict glycemic control during the acute phase of stroke conveys no beneficial effect.

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