An autopsy case of corticobasal syndrome with pure diffuse Lewy Body Disease.

Corticobasal syndrome (CBS) is associated with diverse pathological substrates such as tau, prion protein, transactive response and, rarely, alpha synuclein. We report the case of a54-year-old man, who presented with asymmetric levodopa-poor-responsive parkinsonism, frontal lobe signs and behavioral changes. He was diagnosed with CBS, and postmortem analyses revealed Lewy body disease Braak stage VI without comorbid pathologies. Retrospectively, the clinical course of our patient and previous reports indicate that CBS plus mood changes and autonomic dysfunction, including reduced uptake of metaiodobenzylguanidine, are predictive factors of Lewy body pathology, even if the clinical picture is atypical.

An adult nemaline myopathy patient with respiratory and heart failure harboring a novel NEB variant.

Nemaline myopathy is a heterogeneous disorder of skeletal muscle, and histologically characterized by the presence of nemaline bodies in muscle fibers. Patients with typical congenital form of nemaline myopathy initially present with proximal but later also distal muscle weakness, mostly involving facial and respiratory muscle. Cardiac involvement has been rarely observed especially in nebulin-related nemaline myopathy and there have been only two reports about nebulin-related nemaline myopathy patients with cardiac involvement. We present here the case of a 65-year-old woman manifesting slowly progressive distal myopathy with respiratory and heart failure. She harbored two variants in the nebulin gene, c.20131C > T (p.Arg6711Trp) and c.674C > T (p.Pro225Leu), and one of them, c.674C > T, was a novel variant. In this report, we discuss the pathogenicity of the novel variant and its association with clinical phenotypes including cardiac involvement.

The 2-Minute Spontaneous Swallowing Screening Predicts Independence on Enteral Feeding in Patients with Acute Stroke.

BACKGROUND: It is recommended that enteral feeding should be offered to patients with dysphagia estimated to be unable to take adequate diet orally within 7 days of admission after acute stroke, but there is no clear criterion for initiation of enteral feeding. Recent studies have reported that the frequency of spontaneous swallowing is useful in screening for dysphagia in acute stroke. The present study was aimed to investigate whether measurement of frequency of spontaneous swallowing for 2 minutes could predict independence on enteral feeding 1 week after admission in patients with acute stroke. METHODS: Patients with acute stroke were subjected. Within 72 hours of stroke onset, the number of swallows for 2 minutes was measured by auscultation. Subsequently, 1-hour frequency of spontaneous swallowing was measured using a laryngeal microphone. Functional Oral Intake Scale (FOIS) was evaluated 1 week after admission. RESULTS: Twenty-six out of 40 patients were independent on enteral feeding 1 week after admission based on FOIS. The presence of spontaneous swallowing for 2 minutes had .89 sensitivity, .54 specificity to predict independence on enteral feeding 1 week after admission, whereas the 1-hour frequency of spontaneous swallowing had 1.00 sensitivity, .46 specificity. Logistic regression analysis demonstrated that the presence of spontaneous swallowing for 2 minutes was independent predictor for independence on enteral feeding 1 week after admission, independently of age, sex, and NIHSS. CONCLUSIONS: The 2-minute spontaneous swallowing screening predicts independence on enteral feeding 1 week after admission in patients with acute stroke.

Development of demyelinating lesions in progressive multifocal leukoencephalopathy (PML): Comparison of magnetic resonance images and neuropathology of post-mortem brain.

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disorder caused by opportunistic infection of JC polyomavirus (JCV). Today, increased attention has been focused on PML development in multiple sclerosis (MS) patients under disease-modifying therapies (DMT). Although in the acquired immunodeficiency syndrome (AIDS) era, PML was thought to be a rapidly progressive disease with poor prognosis, drug-associated PML is relatively slow in progress, and a favorable outcome may be expected with early diagnosis. However, early PML diagnosis on magnetic resonance imaging (MRI) is frequently difficult, and JCV DNA copy number in cerebrospinal fluid (CSF) is usually low. To facilitate early PML diagnosis on MRI, the pre-mortem images were compared with neuropathology of the post-mortem brain, and underlying pathology corresponding to the MRI findings was evaluated. As a result, PML lesions of the autopsied brain were divided into three parts, based on the disease extension patterns: (A) Progressive white matter lesion in the right frontoparietal lobe including the precentral gyrus. Huge demyelinated lesions were formed with fusions of numerous small lesions. (B) Central lesion including deep gray matters, such as the putamen and thalamus. The left thalamic lesion was contiguous with the pontine tegmentum. (C) Infratentorial lesion of brainstem and cerebellum. Demyelination in the pontine basilar region and in cerebellar white matter was contiguous via middle cerebellar peduncles (MCPs). In addition, (D) satellite lesions were scattered all over the brain. These observations indicate that PML lesions likely evolve with three steps in a tract-dependent manner: (1) initiation; (2) extension/expansion of demyelinating lesions; and (3) fusion. Understanding of the PML disease evolution patterns would enable confident early diagnosis on MRI, which is essential for favorable prognosis with good functional outcome.

Functional evaluation of PDGFB-variants in idiopathic basal ganglia calcification, using patient-derived iPS cells.

Causative genes in patients with idiopathic basal ganglia calcification (IBGC) (also called primary familial brain calcification (PFBC)) have been reported in the past several years. In this study, we surveyed the clinical and neuroimaging data of 70 sporadic patients and 16 families (86 unrelated probands in total) in Japan, and studied variants of PDGFB gene in the patients. Variant analyses of PDGFB showed four novel pathogenic variants, namely, two splice site variants (c.160 + 2T > A and c.457-1G > T), one deletion variant (c.33_34delCT), and one insertion variant (c.342_343insG). Moreover, we developed iPS cells (iPSCs) from three patients with PDGFB variants (c.160 + 2T > A, c.457-1G > T, and c.33_34 delCT) and induced endothelial cells. Enzyme-linked immunoassay analysis showed that the levels of PDGF-BB, a homodimer of PDGF-B, in the blood sera of patients with PDGFB variants were significantly decreased to 34.0% of that of the control levels. Those in the culture media of the endothelial cells derived from iPSCs of patients also significantly decreased to 58.6% of the control levels. As the endothelial cells developed from iPSCs of the patients showed a phenotype of the disease, further studies using IBGC-specific iPSCs will give us more information on the pathophysiology and the therapy of IBGC in the future.

Relationship Between Frequency of Spontaneous Swallowing and Salivary Substance P Level in Patients with Acute Stroke.

The frequency of spontaneous swallowing is useful for screening of dysphagia in acute stroke. Low levels of substance P (SP) in saliva attenuate the swallowing reflex. The aim of this study was to determine the relationship between the frequency of spontaneous swallowing and salivary SP levels. In 40 subjects, saliva was collected within 72 h after stroke onset and salivary SP levels were measured using ELISA kit at a later date. The frequency of spontaneous swallowing was measured over 1 h using a microphone placed on the neck. Pneumonia was diagnosed by the presence of pyrexia and at least two respiratory problems of four categories (sputum, cough or breathing pattern, breath sound, and gas change). The presence of detectable levels of SP in the saliva was confirmed in 17 patients (high SP group), whereas the level was below the detection limit of the ELISA kit in 23 patients (low SP group). The frequency of spontaneous swallowing was significantly lower in low SP group (16.1 ± 11.6 per hour) than in the high SP group (30.4 ± 20.4, p = 0.016). As the result of multiple regression analysis, salivary SP levels were correlated with frequency of spontaneous swallowing independently of age, NIHSS, and GCS. The incidence of pneumonia was significantly higher in the low than high SP group (p < 0.001). In conclusion, the frequency of spontaneous swallowing was decreased in acute stroke patients with low salivary SP levels. Salivary SP levels can be potentially a useful biomarker of risk of stroke-associated pneumonia in the acute stage.

Embolic stroke during apixaban therapy for left atrial appendage thrombus.

Left atrial appendage (LAA) thrombus is associated with atrial fibrillation (AF) and is a powerful predictor of cardiogenic thromboembolism. Warfarin is an established anticoagulant therapy for patients with LAA thrombus to prevent thromboembolic complications. Apixaban is superior to warfarin in the prevention of thromboembolic complications in patients with AF, and there are case reports showing apixaban-associated resolution of LAA thrombus; however, the efficacy and safety of apixaban for the treatment of LAA thrombus remains unproven. Here we report a patient who experienced embolic stroke while taking apixaban for the treatment of LAA thrombus. Thrombolysis therapy was initiated at the onset of stroke and the patient recovered remarkably. Apixaban is known to make thrombi mobile and/or fragile by shifting the coagulation/fibrinolysis balance to a relative predominance of fibrinolytic activity; therefore, it is necessary to monitor for thromboembolic complications after the initiation of apixaban for the treatment of pre-existing LAA thrombus.

Posterior cerebral artery laterality on magnetic resonance angiography predicts long-term functional outcome in middle cerebral artery occlusion.

BACKGROUND AND PURPOSE: Prominent posterior cerebral artery (PCA) laterality upon 3-dimensional time-of-flight magnetic resonance angiography is often encountered in patients with middle cerebral artery occlusion. We hypothesized that this sign is correlated with improved functional outcome in patients with middle cerebral artery occlusion treated with intravenous recombinant tissue plasminogen activator. METHODS: Fifty acute ischemic stroke patients with middle cerebral artery occlusion were treated with intravenous recombinant tissue plasminogen activator from April 2007 to October 2009. All patients routinely underwent initial (first 3 hours) magnetic resonance scans on admission, and additional follow-up (14-21 days after stroke onset) computed tomography scans. Two film readers blinded to all clinical information assessed the presence or absence of PCA laterality on magnetic resonance angiography. We retrospectively analyzed the clinical and radiologic data on all patients. RESULTS: Out of 50 patients, 20 showed PCA laterality on magnetic resonance angiography. National Institute of Health Stroke Scale score 7 days after stroke onset was significantly lower (P=0.007), and infarct volume on follow-up computed tomography was significantly smaller (P=0.009) in patients with PCA laterality than in patients without this sign. Multivariate logistic regression analyses showed an adjusted odds ratio of 8.49 for a favorable outcome (modified Rankin Scale score 0-1 at 6 months) in patients with PCA laterality (95% CI: 1.82 to 55.8, P=0.005). CONCLUSIONS: The presence of PCA laterality on magnetic resonance angiography before intravenous recombinant tissue plasminogen activator can be used as a predictor of favorable functional outcome in patients with middle cerebral artery occlusion, probably due to improvement of recanalization rate.

Autoimmune polyendocrine syndrome-3 in a patient with late-onset multiple sclerosis.

We present here the rare case of a 73-year-old patient with very late-onset multiple sclerosis who developed autoimmune polyendocrine syndrome (APS)-3. Despite only a few reports describing the association between multiple sclerosis and APS, both of these diseases have been shown to be associated with HLA-DR4. Intriguingly, the HLA genotype profile of this patient included HLA-DR4 which, fine mapped to the DRB1*0405-DQA1*0303-DQB1*0401 extended haplotype, reported to be a susceptibility haplotype for APS-3 in Japan. This unique genetic background might explain the clinical picture of this patient.

Amyloid precursor-like protein 2 cleavage contributes to neuronal intranuclear inclusions and cytotoxicity in spinocerebellar ataxia-7 (SCA7).

In spinocerebellar ataxia-7 (SCA7), a polyglutamine (polyQ) expansion in the ataxin-7 protein leads to the formation of neuronal intranuclear inclusions (NIIs) and neurodegeneration. In this study, amyloid precursor-like protein 2 (APLP2) was identified as a partner protein for ataxin-7. APLP2, belonging to the APP gene family, undergoes secretase and caspase cleavages and has been implicated in the pathogenesis of Alzheimer's disease (AD). Activated caspase-3 cleaves APP family proteins to release N-terminal fragments (NTFs) and intracellular C-terminal domains (ICDs), which can translocate into the nucleus and induce neurotoxicity in AD. Here, we report abnormal nuclear relocation of APLP2 and detection of NTFs in NIIs in SCA7. The ICDs generated by caspase-3 cleavage of APLP2 accumulate in nuclei and contribute to a cumulative toxicity when coexpressed with mutated ataxin-7. Our data suggest that the interaction between APLP2 and ataxin-7 and proteolytic processing of APLP2 may contribute to the pathogenesis of SCA7.

The carboxy-terminal fragment of alpha(1A) calcium channel preferentially aggregates in the cytoplasm of human spinocerebellar ataxia type 6 Purkinje cells.

Spinocerebellar ataxia type 6 (SCA6) is an autosomal dominant neurodegenerative disease caused by a small polyglutamine (polyQ) expansion (control: 4-20Q; SCA6: 20-33Q) in the carboxyl(C)-terminal cytoplasmic domain of the alpha(1A) voltage-dependent calcium channel (Ca(v)2.1). Although a 75-85-kDa Ca(v)2.1 C-terminal fragment (CTF) is toxic in cultured cells, its existence in human brains and its role in SCA6 pathogenesis remains unknown. Here, we investigated whether the small polyQ expansion alters the expression pattern and intracellular distribution of Ca(v)2.1 in human SCA6 brains. New antibodies against the Ca(v)2.1 C-terminus were used in immunoblotting and immunohistochemistry. In the cerebella of six control individuals, the CTF was detected in sucrose- and SDS-soluble cytosolic fractions; in the cerebella of two SCA6 patients, it was additionally detected in SDS-insoluble cytosolic and sucrose-soluble nuclear fractions. In contrast, however, the CTF was not detected either in the nuclear fraction or in the SDS-insoluble cytosolic fraction of SCA6 extracerebellar tissues, indicating that the CTF being insoluble in the cytoplasm or mislocalized to the nucleus only in the SCA6 cerebellum. Immunohistochemistry revealed abundant aggregates in cell bodies and dendrites of SCA6 Purkinje cells (seven patients) but not in controls (n = 6). Recombinant CTF with a small polyQ expansion (rCTF-Q28) aggregated in cultured PC12 cells, but neither rCTF-Q13 (normal-length polyQ) nor full-length Ca(v)2.1 with Q28 did. We conclude that SCA6 pathogenesis may be associated with the CTF, normally found in the cytoplasm, being aggregated in the cytoplasm and additionally distributed in the nucleus.

SUMOylation attenuates the aggregation propensity and cellular toxicity of the polyglutamine expanded ataxin-7.

Post-translational modification by SUMO (small ubiquitin-like modifier) was proposed to modulate the pathogenesis of several neurodegenerative diseases. Spinocerebellar ataxia type 7 (SCA7) is a neurodegenerative disorder, whose pathology is caused by an expansion of a polyglutamine stretch in the protein ataxin-7 (ATXN7). Here, we identified ATXN7 as new target for SUMOylation in vitro and in vivo. The major SUMO acceptor site was mapped to lysine 257, which is part of an evolutionarily conserved consensus SUMOylation motif. SUMOylation did not influence the subcellular localization of ATXN7 nor its interaction with components of the TFTC/STAGA complex. Expansion of the polyglutamine stretch did not impair the SUMOylation of ATXN7. Furthermore, SUMO1 and SUMO2 colocalized with ATXN7 in a subset of neuronal intranuclear inclusions in the brain of SCA7 patients and SCA7 knock-in mice. In a COS-7 cellular model of SCA7, in addition to diffuse nucleoplasmic staining we identified two populations of nuclear inclusions: homogenous or non-homogenous. Non-homogenous inclusions showed significantly reduced colocalization with SUMO1 and SUMO2, but were highly enriched in Hsp70, 19S proteasome and ubiquitin. Interestingly, they were characterized by increased staining with the apoptotic marker caspase-3 and by disruption of PML nuclear bodies. Importantly, preventing the SUMOylation of expanded ATXN7 by mutating the SUMO site increased both the amount of SDS-insoluble aggregates and of caspase-3 positive non-homogenous inclusions, which act toxic to the cells. Our results demonstrate an influence of SUMOylation on the multistep aggregation process of ATXN7 and implicate a role for ATXN7 SUMOylation in SCA7 pathogenesis.

Brain perfusion abnormalities in a sibship with parkin-linked parkinsonism.

We demonstrated brain perfusion abnormalities in a sibship with parkin-linked parkinsonism. The sibship consisted of a 64-year-old man and a 62-year-old woman. Both patients had homozygous deletions of exon 4 in the parkin gene. Hypoperfusion in the superior and middle frontal gyrus, and head of caudate nucleus was seen by SPECT with easy Z score imaging system in both patients. These findings may reflect their executive dysfunction demonstrated by neuropsychological tests.

UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase in nuclei and rimmed vacuoles of muscle fibers in DMRV (distal myopathy with rimmed vacuoles).

BACKGROUND: UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) is a key molecule in the pathogenesis of distal myopathy with rimmed vacuoles (DMRV) and hereditary inclusion body myopathy (HIBM) and almost all such patients have some mutations in GNE. However, subcellular localization of GNE and the mechanism of muscular damage have not been clarified. METHODS: A rabbit polyclonal antibody for GNE was prepared. Immunohistochemistry was performed using anti-GNE and anti-nuclear protein antibodies. Western blotting with subcellular fractionated proteins was performed to determine subcellular localization of GNE. The sizes of myonuclei were quantified in muscle biopsies from patients with DMRV and amyotrophic lateral sclerosis (ALS). RESULTS: In DMRV muscles, immunohistochemistry identified GNE in sarcoplasm and specifically in myonuclei and rimmed vacuoles (RV). Nuclear proteins were also found in RVs. Immunohistochemistry showed colocalization of GNE and emerin in C2C12 cells. Western blotting revealed the presence of GNE in nuclear fractions of human embryonic kidney (HEK) 293T cells. The mean size of myonuclei of DMRV was significantly larger than that of ALS. CONCLUSION: GNE is present in myonuclei near nuclear membrane. Our results suggest that myonuclei are involved in RV formation in DMRV, and that mutant GNE in myonuclei seems to play some role in this process.

PML clastosomes prevent nuclear accumulation of mutant ataxin-7 and other polyglutamine proteins.

The pathogenesis of spinocerebellar ataxia type 7 and other neurodegenerative polyglutamine (polyQ) disorders correlates with the aberrant accumulation of toxic polyQ-expanded proteins in the nucleus. Promyelocytic leukemia protein (PML) nuclear bodies are often present in polyQ aggregates, but their relation to pathogenesis is unclear. We show that expression of PML isoform IV leads to the formation of distinct nuclear bodies enriched in components of the ubiquitin-proteasome system. These bodies recruit soluble mutant ataxin-7 and promote its degradation by proteasome-dependent proteolysis, thus preventing the aggregate formation. Inversely, disruption of the endogenous nuclear bodies with cadmium increases the nuclear accumulation and aggregation of mutant ataxin-7, demonstrating their role in ataxin-7 turnover. Interestingly, beta-interferon treatment, which induces the expression of endogenous PML IV, prevents the accumulation of transiently expressed mutant ataxin-7 without affecting the level of the endogenous wild-type protein. Therefore, clastosomes represent a potential therapeutic target for preventing polyQ disorders.

An autosomal dominant cerebellar ataxia linked to chromosome 16q22.1 is associated with a single-nucleotide substitution in the 5' untranslated region of the gene encoding a protein with spectrin repeat and Rho guanine-nucleotide exchange-factor domains.

Autosomal dominant cerebellar ataxia (ADCA) is a group of heterogeneous neurodegenerative disorders. By positional cloning, we have identified the gene strongly associated with a form of degenerative ataxia (chromosome 16q22.1-linked ADCA) that clinically shows progressive pure cerebellar ataxia. Detailed examination by use of audiogram suggested that sensorineural hearing impairment may be associated with ataxia in our families. After restricting the candidate region in chromosome 16q22.1 by haplotype analysis, we found that all patients from 52 unrelated Japanese families harbor a heterozygous C-->T single-nucleotide substitution, 16 nt upstream of the putative translation initiation site of the gene for a hypothetical protein DKFZP434I216, which we have called "puratrophin-1" (Purkinje cell atrophy associated protein-1). The full-length puratrophin-1 mRNA had an open reading frame of 3,576 nt, predicted to contain important domains, including the spectrin repeat and the guanine-nucleotide exchange factor (GEF) for Rho GTPases, followed by the Dbl-homologous domain, which indicates the role of puratrophin-1 in intracellular signaling and actin dynamics at the Golgi apparatus. Puratrophin-1--normally expressed in a wide range of cells, including epithelial hair cells in the cochlea--was aggregated in Purkinje cells of the chromosome 16q22.1-linked ADCA brains. Consistent with the protein prediction data of puratrophin-1, the Golgi-apparatus membrane protein and spectrin also formed aggregates in Purkinje cells. The present study highlights the importance of the 5' untranslated region (UTR) in identification of genes of human disease, suggests that a single-nucleotide substitution in the 5' UTR could be associated with protein aggregation, and indicates that the GEF protein is associated with cerebellar degeneration in humans.

A clinical and genetic study in a large cohort of patients with spinocerebellar ataxia type 6.

In order to clarify the clinical and genetic features of SCA6, we retrospectively analyzed 140 patients. We observed an inverse correlation between the age of onset and the length of the expanded allele, and also between the age of onset and the sum of CAG repeats in the normal and the expanded alleles. The ages of onset of four homozygous patients correlated better with the sum of CAG repeats in both alleles rather than with the expanded allele calculated from heterozygous SCA6 subjects. Clinically, unsteadiness of gait was the main initial symptom, followed by vertigo and oscillopsia, and cerebellar signs were detected in nearly 100% of the patients. In contrast, extracerebellar signs were relatively mild and infrequent. The results of neuro-otological examination performed in 22 patients suggested the purely cerebellar abnormalities of ocular movements in nature. There was a close relationship between downbeat positioning nystagmus (DPN) and positioning vertigo, which became more common in the later stage. We conclude that total number of CAG repeat-units in both alleles is a good parameter for assessment of age of onset in SCA6 including homozygous patients. In addition, clinical and neuro-otological examinations suggested that SCA6 is a disease with predominantly cerebellar dysfunction.