An NEFH founder mutation causes broad phenotypic spectrum in multiple Japanese families.

BACKGROUND AND AIMS: Mutations in neurofilament genes have been linked to several neuromuscular disorders. The neurofilament heavy (NEFH) gene was identified as the causative gene of Charcot-Marie-Tooth disease type 2CC (CMT2CC) in 2016, with a toxic gain of function mechanism caused by the translation and aggregation of cryptic amyloidogenic element (CAE) in the 3' untranslated region (UTR). But the NEFH-related clinical and genetic spectrums are still unclear in Japan. METHODS: We analyzed all variants in the NEFH gene from our in-house whole-exome sequencing data, established from Japanese nationwide patients with neuromuscular disorders, including Charcot-Marie-Tooth (CMT) disease and spinal muscular atrophy (SMA). RESULTS: We identified a c.3017dup (p.Pro1007Alafs*56) variant in NEFH from three families clinically diagnosed with CMT, and one family with SMA. In addition to the patients presented with typical peripheral neuropathies, pyramidal signs were observed from one CMT patient. Whereas the SMA patients showed severe characteristic weakness of triceps brachii and quadriceps femoris. All of these four families reside in Kagoshima Prefecture of Japan, and a following haplotype analysis strongly suggests a founder effect. INTERPRETATION: This is the original report referring to a founder mutation in NEFH. The clinical diversity in our study, comprising CMT, with or without pyramidal signs, and SMA, suggest an extensive involvement of peripheral nerve, anterior horn cells, or both. Our findings broaden the phenotypic spectrum of NEFH-related disorders.

A homozygous mutation of VWA3B causes cerebellar ataxia with intellectual disability.

BACKGROUND: Hereditary cerebellar ataxia constitutes a heterogeneous group of neurodegenerative disorders, occasionally accompanied by other neurological features. Genetic defects remain to be elucidated in approximately 40% of hereditary cerebellar ataxia cases in Japan. We attempted to identify the gene responsible for autosomal recessive cerebellar ataxia with intellectual disability. METHODS: The present study involved three patients in a consanguineous Japanese family. Neurological examination and gene analyses were performed in all family members. We performed genome-wide linkage analysis including single nucleotide polymorphism arrays, copy-number variation analysis and whole exome sequencing. To clarify the functional alteration resulting from the identified mutation, we performed cell viability assay of cultured cells expressing mutant protein. RESULTS: One homozygous region shared among the three patients on chromosomes 2p16.1-2q12.3 was identified. Using whole exome sequencing, six homozygous variants in genes in the region were detected. Only one variant, VWA3B c.A1865C, results in a change of a highly conserved amino acid (p.K622T) and was not present in control samples. VWA3B encodes a von Willebrand Factor A Domain-Containing Protein 3B with ubiquitous expression, including the cerebellum. The viability of cultured cells expressing the specific K622T mutation was proved to decrease through the activation of apoptotic pathway. CONCLUSIONS: Mutated VWA3B was found to be likely associated with cerebellar degeneration with intellectual disability. Although a rare cause of cerebellar degeneration, these findings indicate a critical role for VWA3B in the apoptosis pathway in neuronal tissues.

Robot-assisted total gastrectomy for gastric cancer in a patient with amyotrophic lateral sclerosis receiving long-term tracheostomy invasive ventilation.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. Although affected patients may develop cancers, major surgical intervention has been hampered by its questionable overall benefit due to limited prognosis and risk of postoperative respiratory collapse. A recent study, however, showed that tracheostomy invasive ventilation (TIV) prolonged median survival to 11.3 years; thus, patients with ALS receiving TIV might benefit from major surgery. A 66-year-old man with ALS, who had received TIV and enteral tube feeding for 8 years, presented with bloody stool. The patient also had type 2 diabetes mellitus, stage 4 chronic kidney disease, abdominal aortic aneurysm, and anti-phospholipid syndrome, as well as multiple episodes of pneumonia and catheter-related urinary tract infection treated by antibiotics. Medical examination and esophagogastroduodenoscopy revealed a type 3 tumor in the middle part of the stomach. The patient's preoperative diagnosis was gastric cancer (GC), MU, type3, Less-Post, T3(SS), N1, H0, P0, M0, cStage III. The estimated mortality rate was 30.5%, according to the Japanese National Clinical Database. The patient and his family were fully informed of the risk of surgery; the patient clearly requested curative surgery by eye movement. Thus, robot-assisted total gastrectomy (RATG) was performed. The tissues were extremely fragile and hemorrhagic. The surgical time was 7 h 0 min; intraoperative blood loss was 324 ml. Pathological examination revealed GC, MU, type3, T4a(SE), N2, H0, CY0, P0, M0 fStage IIIB. The postoperative course was uneventful. He has remained in stable condition for 3 months. Our findings suggest that patients with ALS who achieve longer survival with TIV can undergo major cancer surgery, including robot-assisted surgery, which may facilitate a better mid-long-term prognosis. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13691-021-00499-7.

[A case of Wegener's granulomatosis presenting with tonic-clonic status epilepticus].

A 47-year-old man with a diagnosis of paranasal Wegener's granulomatosis was admitted to our hospital for generalized seizures. He had been treated with long-term predonine therapy after the initial onset of Wegener's granulomatosis. The ictal EEG showed generalized spike and wave complexes, mainly presenting in the bifrontal areas. The postictal EEG revealed periodic localized sharp discharges in the left frontal area. At the initial seizure onset, a midline multilobular mass lesion having a heterogeneous enhancement effect was detected in the lower frontal lobe on gadolinium-enhanced T1-weighted imaging (Gd T1-WI). The anterior skull base and bifrontal lobes were encroached by upward contiguous invasion of the midline mass lesion from the ethmoid sinus on Gd T1-WI. The high signal intensity lesions in the bifrontal lobes on T2- and Gd T1-WI resolved with palliative predonine therapy following methylpredonisolone pulse therapy. Recurrent generalized tonic-clonic status epilepticus was caused by the granulomatous lesion encroaching on the frontal lobe with contiguous invasion from the paranasal Wegener's granulomatosis.

Increased serum alkaline phosphatase and early neurological deterioration in patients with atherothrombotic brain infarction attributable to intracranial atherosclerosis.

OBJECTIVE: The purpose of this study was to determine whether increased alkaline phosphatase (ALP) was associated with early neurological deterioration (END) in patients with atherothrombotic brain infarction (ATBI) attributable to intracranial atherosclerosis (ICAS) or not. METHODS: We analyzed data derived from 70 patients (47 men; mean age, 72.4 ± 12.8 years) with symptomatic ICAS who were admitted within 3 days of ATBI onset between April 2013 and December 2018. We defined END as an increase of ≥2 in the National Institutes of Health Stroke Scale scores during the first 72 h of hospitalization. RESULTS: Eleven (15.7%) patients had END. Serum ALP levels on admission were significantly higher among patients with, than without END (median [interquartile range], 296 [233-338] vs. 216 [187-262] U/L, p = .0081). CONCLUSION: Increased serum ALP levels on admission may be able to predict developing END in patients with symptomatic ICAS.

[Acute myelitis associated with anti-neutral glycolipid antibody].

A 48-year-old man with rapid onset of fever elevation developed acute myelitis over a period of a week. MRI of the spinal cord revealed a longitudinal T2-hyperintense intraspinal lesion extending from C6 to Th8 level. Clinical symptoms and findings resolved with immunotherapy. In serological analysis, no antibodies related to various collagen diseases, anti-aquaporin-4 (AQP4) antibody and anti-myelin oligodendrocyte glycoprotein (MOG) antibody were detected. Anti-lactosylceramide (LacCer) antibodies were detected in the acute phase of serum and cerebrospinal fluid, with titers showing decrements in the recovery phase. The present case supports the notion that acute myelitis can occur as an anti-neutral glycolipid antibody-related disorder. Anti-neutral glycolipid antibodies should be examined in future pertinent cases of myelitis.

[Cerebellar and brainstem hypoperfusion in Bickerstaff's brainstem encephalitis: a case report].

A 16-year-old healthy male experienced gastrointestinal symptoms and 9 days later developed fever, headache, numbness of the left hand, and disturbance of consciousness with rapid deterioration to a comatose state. These clinical symptoms resolved after treatment with steroid pulse, plasma exchange, and intravenous immunoglobulin. Along with the recovery, ophthalmoplegia and ataxia were observed. These symptoms and the detection of a high titer of serum anti-GQ1b immunoglobulin G autoantibodies led to the diagnosis of Bickerstaff's brainstem encephalitis (BBE). Brain 123I-IMP SPECT indicated hypoperfusion of the brainstem and bilateral cerebellar cortex during the acute phase, which increased during the recovery phase. This finding is indicative of reversible dysfunction in the cerebellar cortex and brainstem in the acute phase of BBE.

Possible reduced penetrance of expansion of 44 to 47 CAG/CAA repeats in the TATA-binding protein gene in spinocerebellar ataxia type 17.

BACKGROUND: Spinocerebellar ataxia type 17 (SCA17) is an autosomal dominant cerebellar ataxia caused by expansion of CAG/CAA trinucleotide repeats in the TATA-binding protein (TBP) gene. Because the number of triplets in patients with SCA17 in previous studies ranged from 43 to 63, the normal number of trinucleotide units has been considered to be 42 or less. However, some healthy subjects in SCA17 pedigrees carry alleles with the same number of expanded repeats as patients with SCA17. OBJECTIVE: To investigate the minimum number of CAG/CAA repeats in the TBP gene that causes SCA17. DESIGN: We amplified the region of the TBP gene containing the CAG/CAA repeat by means of polymerase chain reaction and performed fragment and sequence analyses. PATIENTS: The subjects included 734 patients with SCA (480 patients with sporadic SCA and 254 patients with familial SCA) without CAG repeat expansions at the SCA1, SCA2, Machado-Joseph disease, SCA6, SCA7, or dentatorubral-pallidolluysian atrophy loci, with 162 healthy subjects, 216 patients with Parkinson disease, and 195 with Alzheimer disease as control subjects. RESULTS: Eight patients with SCA possessed an allele with more than 43 CAG/CAA repeats. Among the non-SCA groups, alleles with 43 to 45 repeats were seen in 3 healthy subjects and 2 with Parkinson disease. In 1 SCA pedigree, a patient with possible SCA17 and her healthy sister had alleles with 45 repeats. A 34-year-old man carrying alleles with 47 and 44 repeats (47/44) had developed progressive cerebellar ataxia and myoclonus at 25 years of age, and he exhibited dementia and pyramidal signs. He was the only affected person in his pedigree, although his father and mother carried alleles with mildly expanded repeats (44/36 and 47/36, respectively). In another pedigree, 1 patient carried a 43-repeat allele, whereas another patient had 2 normal alleles, indicating that the 43-repeat allele may not be pathologic in this family. CONCLUSIONS: We estimate that 44 CAG/CAA repeats is the minimum number required to cause SCA17. However, the existence of unaffected subjects with mildly expanded triplets suggests that the TBP gene mutation may not penetrate fully. Homozygosity of alleles with mildly expanded triplet repeats in the TBP gene might contribute to the pathologic phenotype.

A novel haplotype of spinocerebellar ataxia type 6 contributes to the highest prevalence in western Japan.

The highest prevalence rate of spinocerebellar ataxia type 6 (SCA6) in the worldwide population is in the Chugoku and Kansai areas of Western Japan, but the reason of this geographic characteristics is unclear. We investigated the predisposing haplotypes and their geographic distribution. Genotyping of five microsatellite markers and three single nucleotide polymorphisms linked to the CACNA1A gene in 150 Japanese SCA6 patients from unrelated 118 families revealed three major haplotypes, carrying a pool of one common haplotype core. A founder chromosome was thought to have historically diverged into at least three types. One of the major haplotypes newly identified showed a strong geographical cluster around the Seto Inland Sea in the Chugoku and Kansai areas of Western Japan, whereas the others were widely distributed throughout Japan. The distribution of predisposing haplotypes contributes to the geographical differences in prevalence of SCA6.

Dinucleotide repeat polymorphisms in the neprilysin gene are not associated with sporadic Alzheimer's disease.

In the pathological process of Alzheimer's disease (AD), deposition of amyloid beta-peptide (A beta) in the brain parenchyma plays an important role. Neprilysin (NEP), a neutral endopeptidase, degrades A beta, and it is postulated that decreased NEP activity may contribute to the development of AD by promoting the accumulation of A beta. The human NEP gene possesses four dinucleotide repeat polymorphisms, and it is possible that these polymorphisms regulate the NEP expression levels and influence the pathological cascade of AD. Therefore, we investigated the association of these polymorphisms with AD. We performed genotyping of each polymorphism in 201 Japanese sporadic AD patients and 208 Japanese controls. There were no significant differences between the AD and control groups in allele frequencies of each polymorphism. We conclude that these polymorphisms in the NEP gene do not contribute to genetic risk factors for sporadic AD.

[Cerebral peduncle infarction with pure dysarthria--case report].

A 82 year-old male having a long history of hypertension was admitted for dysarthria. Neurological examination revealed dysarthria with mild disturbance of left-sided soft palate elevation. No lingual palsy nor facial weakness were noted. No motor weakness in the upper and lower extremities was noted. Diffusion-weighted image and T2 weighted image revealed a small high signal lesion localized in the medial one-third of the left cerebral peduncle. There were bilateral stenotic lesions of the posterior cerebral artery at P1 portion in intracranial magnetic resonance angiography. Pure dysarthria can be caused by disruption of the supranuclear fiber of glossopharyngeal and vagal nerve nucleus in the corticobulbar tract, which can be localized in the medial portion of the cerebral peduncle.