CHCHD2 P14L, found in amyotrophic lateral sclerosis, exhibits cytoplasmic mislocalization and alters Ca2+ homeostasis.

CHCHD2 and CHCHD10, linked to Parkinson's disease and amyotrophic lateral sclerosis-frontotemporal dementia (ALS), respectively, are mitochondrial intermembrane proteins that form a heterodimer. This study aimed to investigate the impact of the CHCHD2 P14L variant, implicated in ALS, on mitochondrial function and its subsequent effects on cellular homeostasis. The missense variant of CHCHD2, P14L, found in a cohort of patients with ALS, mislocalized CHCHD2 to the cytoplasm, leaving CHCHD10 in the mitochondria. Drosophila lacking the CHCHD2 ortholog exhibited mitochondrial degeneration. In contrast, human CHCHD2 P14L, but not wild-type human CHCHD2, failed to suppress this degeneration, suggesting that P14L is a pathogenic variant. The mitochondrial Ca2+ buffering capacity was reduced in Drosophila neurons expressing human CHCHD2 P14L. The altered Ca2+-buffering phenotype was also observed in cultured human neuroblastoma SH-SY5Y cells expressing CHCHD2 P14L. In these cells, transient elevation of cytoplasmic Ca2+ facilitated the activation of calpain and caspase-3, accompanied by the processing and insolubilization of TDP-43. These observations suggest that CHCHD2 P14L causes abnormal Ca2+ dynamics and TDP-43 aggregation, reflecting the pathophysiology of ALS.

Neuropathology and emerging biomarkers in corticobasal syndrome.

Corticobasal syndrome (CBS) is a clinical syndrome characterised by progressive asymmetric limb rigidity and apraxia with dystonia, myoclonus, cortical sensory loss and alien limb phenomenon. Corticobasal degeneration (CBD) is one of the most common underlying pathologies of CBS, but other disorders, such as progressive supranuclear palsy (PSP), Alzheimer's disease (AD) and frontotemporal lobar degeneration with TDP-43 inclusions, are also associated with this syndrome.In this review, we describe common and rare neuropathological findings in CBS, including tauopathies, synucleinopathies, TDP-43 proteinopathies, fused in sarcoma proteinopathy, prion disease (Creutzfeldt-Jakob disease) and cerebrovascular disease, based on a narrative review of the literature and clinicopathological studies from two brain banks. Genetic mutations associated with CBS, including GRN and MAPT, are also reviewed. Clinicopathological studies on neurodegenerative disorders associated with CBS have shown that regardless of the underlying pathology, frontoparietal, as well as motor and premotor pathology is associated with CBS. Clinical features that can predict the underlying pathology of CBS remain unclear. Using AD-related biomarkers (ie, amyloid and tau positron emission tomography (PET) and fluid biomarkers), CBS caused by AD often can be differentiated from other causes of CBS. Tau PET may help distinguish AD from other tauopathies and non-tauopathies, but it remains challenging to differentiate non-AD tauopathies, especially PSP and CBD. Although the current clinical diagnostic criteria for CBS have suboptimal sensitivity and specificity, emerging biomarkers hold promise for future improvements in the diagnosis of underlying pathology in patients with CBS.

Urine levels of the polyglutamine ataxin-3 protein are elevated in patients with spinocerebellar ataxia type 3.

INTRODUCTION: Accumulation of polyglutamine (polyQ) ataxin-3 (ATXN3) contributes to the pathobiology of spinocerebellar ataxia type 3 (SCA3). Recently, we showed that polyQ ATXN3 is elevated in the plasma and cerebrospinal fluid (CSF) of SCA3 patients, and has the potential to serve as a biological marker for this disease [1]. Based on these findings, we investigated whether polyQ ATXN3 can also be detected in urine samples from SCA3 patients. METHODS: We analyzed urine samples from 30 SCA3 subjects (including one pre-symptomatic subject), 35 subjects with other forms of ataxia, and 37 healthy controls. To quantify polyQ ATXN3 protein levels, we used our previously developed immunoassay. RESULTS: PolyQ ATXN3 can be detected in the urine of SCA3 patients, but not in urine samples from healthy controls or other forms of ataxia. There was a significant statistical association between polyQ ATXN3 levels in urine samples and those in plasma. Further, the levels of polyQ ATXN3 urine associated with an earlier age of SCA3 disease onset. CONCLUSION: As clinical trials for SCA3 advance, urine polyQ ATXN3 protein has potential to be a useful, non-invasive and inexpensive biomarker for SCA3.

Next-generation sequencing of 28 ALS-related genes in a Japanese ALS cohort.

We investigated the frequency and contribution of variants of the 28 known amyotrophic lateral sclerosis (ALS)-related genes in Japanese ALS patients. We designed a multiplex, polymerase chain reaction-based primer panel to amplify the coding regions of the 28 ALS-related genes and sequenced DNA samples from 257 Japanese ALS patients using an Ion Torrent PGM sequencer. We also performed exome sequencing and identified variants of the 28 genes in an additional 251 ALS patients using an Illumina HiSeq 2000 platform. We identified the known ALS pathogenic variants and predicted the functional properties of novel nonsynonymous variants in silico. These variants were confirmed by Sanger sequencing. Known pathogenic variants were identified in 19 (48.7%) of the 39 familial ALS patients and 14 (3.0%) of the 469 sporadic ALS patients. Thirty-two sporadic ALS patients (6.8%) harbored 1 or 2 novel nonsynonymous variants of ALS-related genes that might be deleterious. This study reports the first extensive genetic screening of Japanese ALS patients. These findings are useful for developing genetic screening and counseling strategies for such patients.

An autopsied case of adult-onset bulbospinalform Alexander disease with a novel S393R mutation in the GFAP gene.

A 50-year-old Japanese man with no apparent family history noticed diplopia. He gradually showed gait disturbance and dysuria. Abducens disorder of eye movement with nystagmus, tongue atrophy with fasciculation, spastic tetraparesis, and sensory disturbance were also observed. MRI showed severe atrophy of the medulla oblongata to the cervical cord ("tadpole appearance"). Tracheotomy and gastrostomy were performed 7 years after onset due to the development of bulbar palsy. Death occurred following respiratory failure after 11 years total disease duration. The brain weighed 1,380 g. The cerebrum, cerebellum, midbrain, and upper pons were preserved from atrophy, but the medulla oblongata to the cervical cord showed severe atrophy. A few Rosenthal fibers were observed in the cerebral white matter, basal ganglia, and cerebellum, whereas numerous Rosenthal fibers were observed in the medulla oblongata to the cervical cord. Myelin loss with relatively preserved axons was extensively observed from the middle of the pons to the spinal cord. The clinicopathological diagnosis was adult-onset bulbospinal-form Alexander disease. Glial fibrillary acidic protein (GFAP) gene analysis revealed a novel mutation of S393R. Expression patterns of S393R mutant GFAP using adrenal carcinoma-derived cells (SW13 cells) showed a decreased number of filamentous structures and abnormal aggregates.

[Case of rapidly progressive syringomyelia due to a spinal hemangioblastoma].

A 35-year-old man came to the hospital showing signs of worsening dysesthesia on his right hand. The dysesthesia started on his right hand and then spread to his forearm in two months. It also appeared on his left hand transiently. Initial MR imaging revealed a high signal intensity lesion at Th1-Th10 with an irregular margin (presyrinx state) below C3 on T2WI. The legion extended up to the medulla oblongata rapidly. Corticosteroid therapy lead to a slight improvement in dysesthesia symptoms but did not last. Immunosuppressant was also ineffective. Further examination using Gd enhanced MR imaging in a neurosurgery clinic in a university hospital revealed a spinal tumor at the Th10 level. A tumor resection was performed and dysesthesia improved. Pathological analysis showed hemangioblastoma. Presyrinx and syrinx above Th1 disappeared after the operation. It is necessary to search the whole spine carefully for the possibility of a tumor in the case of steroid resistant progressive spinal lesions with an unknown origin. And we stress the importance of timely surgical intervention regardless of idiopathic or secondary syringomyelia. We would like to report this clinical course presenting MR imaging and discuss the mechanism of forming syringomyelia based on the hypothesis of the alteration of CSF flow.

[At-home music therapy intervention using video phone (Skype) for elderly people with dementia].

There are various nonpharmacological therapies available for elderly people with dementia, and these can improve quality of life and the behavioral and psychological symptoms of dementia (BPSD) that appear throughout the progression of the disease. Since a substantial number of effects have been reported for music therapy, we focused on this nonpharmacological intervention. Generally, musical therapy is provided collectively in facilities. However, the music used in this context may not consider the preferences and music abilities of each person. Therefore, in this study we created made-to-order music CDs that accounted for each participant's musical preferences and abilities. Utilizing the CDs, we conducted an intervention study of music therapy using a video phone (Skype) that elderly people with dementia can use at home. An advantage of conducting music therapy for individuals with dementia using a video phone is that those who have difficulty going to the hospital or participating in dementia-related therapy groups can participate in therapy in a familiar place. The results of this intervention showed that participants demonstrated signs of improvement as measured by the smile degree(Smile scan)and Behavior Pathology in Alzheimer's Disease (BEHAVE-AD) scale.

[Corticobasal syndrome: recent advances and future directions].

Corticobasal degeneration (CBD) is a progressive neurodegenerative disorder described by Rebeiz et al. It is characterized by progressive, asymmetric, cortical (eg, apraxia, alien limb phenomena, cortical sensory loss, and myoclonus), and extrapyramidal (eg, rigidity, bradykinesia, dystonia, and tremor) dysfunction. However, CBD has many clinical phenotypes, and the features used for predicting CBD have low sensitivity. Therefore, the term corticobasal syndrome (CBS) has been used to characterize such clinical features, whereas the term CBD is used to refer to the pathological disorder. The most frequent causes of CBS are CBD, followed by Alzheimer's disease, progressive supranuclear palsy, frontotemporal lobar degeneration with TDP-43 pathology (sporadic and familial), Pick's disease, Lewy body disease, frontotemporal lobar degeneration with fused in sarcoma-positive inclusions, Creutzfeldt-Jakob disease, and mutations in the microtubule-associated protein tau (MAPT) and progranulin (GRN) genes. The topography of neurodegeneration dictates the clinical syndrome not according to the underlying pathology. Researchers have attempted to develop fluid biomarkers or imaging analysis for diagnosing CBS. The aim of this review was to highlight recent advances in CBS diagnosis and discuss future directions.

The wide spectrum of clinical manifestations in Sjögren's syndrome-associated neuropathy.

We assessed the clinicopathological features of 92 patients with primary Sjögren's syndrome-associated neuropathy (76 women, 16 men, 54.7 years, age at onset). The majority of patients (93%) were diagnosed with Sjögren's syndrome after neuropathic symptoms appeared. We classified these patients into seven forms of neuropathy: sensory ataxic neuropathy (n = 36), painful sensory neuropathy without sensory ataxia (n = 18), multiple mononeuropathy (n = 11), multiple cranial neuropathy (n = 5), trigeminal neuropathy (n = 15), autonomic neuropathy (n = 3) and radiculoneuropathy (n = 4), based on the predominant neuropathic symptoms. Acute or subacute onset was seen more frequently in multiple mononeuropathy and multiple cranial neuropathy, whereas chronic progression was predominant in other forms of neuropathy. Sensory symptoms without substantial motor involvement were seen predominantly in sensory ataxic, painful sensory, trigeminal and autonomic neuropathy, although the affected sensory modalities and distribution pattern varied. In contrast, motor weakness and muscle atrophy were observed in multiple mononeuropathy, multiple cranial neuropathy and radiculoneuropathy. Autonomic symptoms were often seen in all forms of neuropathy. Abnormal pupils and orthostatic hypotension were particularly frequent in sensory ataxic, painful, trigeminal and autonomic neuropathy. Unelicited somatosensory evoked potentials and spinal cord posterior column abnormalities in MRI were observed in sensory ataxic, painful and autonomic neuropathy. Sural nerve biopsy specimens (n = 55) revealed variable degrees of axon loss. Predominantly large fibre loss was observed in sensory ataxic neuropathy, whereas predominantly small fibre loss occurred in painful sensory neuropathy. Angiitis and perivascular cell invasion were seen most frequently in multiple mononeuropathy, followed by sensory ataxic neuropathy. The autopsy findings of one patient with sensory ataxic neuropathy showed severe large sensory neuron loss paralleling to dorsal root and posterior column involvement of the spinal cord, and severe sympathetic neuron loss. Degrees of neuron loss in the dorsal and sympathetic ganglion corresponded to segmental distribution of sensory and sweating impairment. Multifocal T-cell invasion was seen in the dorsal root and sympathetic ganglion, perineurial space and vessel walls in the nerve trunks. Differential therapeutic responses for corticosteroids and IVIg were seen among the neuropathic forms. These clinicopathological observations suggest that sensory ataxic, painful and perhaps trigeminal neuropathy are related to ganglioneuronopathic process, whereas multiple mononeuropathy and multiple cranial neuropathy would be more closely associated with vasculitic process.

Widespread active inflammatory lesions in a case of HTLV-I-associated myelopathy lasting 29 years.

An autopsy case of human T-lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM) of 29 years' duration is reported. The patient had no history of surgery or blood transfusion and likely contracted HTLV-I sexually while traveling in an endemic area. At age 45, the patient began to experience gait disturbance; he later developed spastic tetraparesis. Autopsy revealed marked gross spinal cord atrophy, particularly in the middle to lower thoracic levels. Myelin and axonal degeneration were identified predominantly in the middle to lower thoracic spinal cord, extending into the medulla oblongata and lumbar cord. Inflammatory infiltrates of mononuclear cells were diffuse in the white and gray matter of the spinal cord and medulla oblongata, particularly in perivascular areas. These infiltrates were also observed in perivascular areas of the pons, midbrain, cerebellum, and cerebrum. More than half of the infiltrating cells were positive for the pan-T cell marker UCHL-1, but some were positive for the B cell marker SL-26. There were far more CD8-positive cells than CD4-positive cells in the spinal parenchyma and perivascular areas. Neurons in the anterior horn, Clarke's column, and intermediolateral column were relatively well preserved. Active chronic inflammation was indicated. Despite the 29-year history of HAM, the presence of an active inflammatory reaction is surprising. We discuss possible modulation of the histopathological manifestations of HAM by corticosteroid therapy.

Neuroradiologic and clinical abnormalities in dementia of diffuse neurofibrillary tangles with calcification (Kosaka-Shibayama disease).

We describe a characteristic dementia patient diagnosed as diffuse neurofibrillary tangles with calcification (DNTC). Neuropsychologically, dementia, including a decline in memory retention and intelligence, and anomic aphasia were recognized. Imaging revealed circumscribed temporal dominant atrophy and calcification of the basal ganglia and cerebellum. SPECT and FDG-PET revealed a remarkable reduction of blood flow and metabolism in the temporal lobes; however, there is no reduction in the basal ganglia and cerebellum, and FDOPA-PET also disclosed no abnormalities. This suggests that calcification and neuronal degeneration occur independently in DNTC.