Satoshi Kuru

Expression of tumor necrosis factor-α in regenerating muscle fibers in inflammatory and non-inflammatory myopathies

Abstract. The expression level of tumor necrosis factor (TNF)-α is elevated in idiopathic inflammatory myopathies and Duchenne muscular dystrophy (DMD), but the precise role of TNF-α is unknown. To elucidate the possible role of TNF-α, we investigated the expression of TNF-α and its receptor in polymyositis (PM), dermatomyositis (DM), and DMD using in situ hybridization (ISH) and immunohistochemistry. We showed that TNF-α mRNA and protein were present in muscle fibers. TNF-α-positive fibers were observed in all cases of PM, DM and DMD, but were rare or absent in neurogenic disorders and normal controls. The proportion of TNF-α-positive fiber showed a significant positive correlation with the proportion of regenerating fibers that were positive for the developmental form of myosin heavy chain (MHC-d). The number of TNF receptor-positive fibers was small. Some muscle fibers expressed both TNF-α and its receptor simultaneously. Our results indicate that TNF-α is produced and expressed by muscle fibers and associated with muscle regeneration.

An autopsy case of spinal muscular atrophy type III (Kugelberg‐Welander disease)

We report an autopsy case of a 67‐year‐old man clinicogenetically diagnosed as having spinal muscular atrophy (SMA) type III (Kugelberg‐Welander disease), showing slowly progressive muscle wasting and weakness of the extremities. His brother showed similar manifestations. Autopsy revealed neuronal loss and severe gliosis in the anterior horns of the spinal cord, a marked neurogenic change of skeletal muscles and mild degeneration of cardiomyocytes. Chromatolytic change was seen in the anterior horn, but not in the Clarkes and thalamic nuclei. The anterior spinal roots were atrophic, and there was loss of myelinated fibers with abundant glial bundles. In addition, degeneration was also observed in the posterior column and dentate nucleus. The pathological features were essentially similar to those of SMA I. Chronic change was prominent while acute change was mild in degree, corresponding to a very long clinical course.

Clinical features and a mutation with late onset of limb girdle muscular dystrophy 2B

Objective and methods Dysferlin encoded by DYSF deficiency leads to two main phenotypes, limb girdle muscular dystrophy (LGMD) 2B and Miyoshi myopathy. To reveal in detail the mutational and clinical features of LGMD2B in Japan, we observed 40 Japanese patients in 36 families with LGMD2B in whom dysferlin mutations were confirmed. Results and conclusions Three mutations (c.1566C>G, c.2997G>T and c.4497delT) were relatively more prevalent. The c.2997G>T mutation was associated with late onset, proximal dominant forms of dysferlinopathy, a high probability that muscle weakness started in an upper limb and lower serum creatine kinase (CK) levels. The clinical features of LGMD2B are as follows: (1) onset in the late teens or early adulthood, except patients homozygous for the c.2997G>T mutation; (2) lower limb weakness at onset; (3) distal change of lower limbs on muscle CT at an early stage; (4) impairment of lumbar erector spinal muscles on muscle CT at an early stage; (5) predominant involvement of proximal upper limbs; (6) preservation of function of the hands at late stage; (7) preservation of strength in neck muscles at late stage; (8) lack of facial weakness or dysphagia; (9) avoidance of scoliosis; (10) hyper-Ckaemia; (11) preservation of cardiac function; and (12) a tendency for respiratory function to decline with disease duration. It is important that the late onset phenotype is found with prevalent mutations.

Autopsy case of hereditary spastic paraplegia with thin corpus callosum showing severe gliosis in the cerebral white matter

We report an autopsy case of a 51‐year‐old man clinically diagnosed with a complicated type of hereditary spastic paraplegia. His sister showed similar manifestations. Gait disturbance was manifested at 14 years of age. Subsequently, slowly progressive spastic tetraplegia developed with mental deterioration, neuropathy and amyotrophy. Marked cerebral atrophy with thin corpus callosum was shown by cranial MRI. Autopsy revealed a severely atrophic brain with extreme thinning of the whole corpus callosum. Microscopically, neurodegeneration was found in the corticospinal tract, thalamus, cerebral white matter and substantia nigra, as well as in the anterior horn and posterior column of the spinal cord. The remaining neurons contained large amounts of lipofuscin and eosinophilic granules. Unique to this patient was the severe gliosis in the cerebral white matter and substantia nigra, suggesting that sufficient development had been established when the degenerative process occurred. The predominant feature of the present case is the neurodegeneration process rather than hypoplasia.

Study of Duchenne muscular dystrophy long-term survivors aged 40 years and older living in specialized institutions in Japan

The national muscular dystrophy wards database of Japan lists 118 long-term Duchenne muscular dystrophy (DMD) patients who were at least 40 years old as of October 1, 2013. To elucidate the clinical features of DMD patients aged 40 years and older, we obtained gene analysis and muscle biopsy findings, as well as medical condition information. Ninety-four of the registered patients consented to participate, of whom 55 meeting genetic or biochemical criteria confirming DMD were analyzed. The mean age at the time of the study was 43.6 ± 3.0 years, while at the time of independent ambulation loss it was 10.6 ± 1.5 years and at mechanical ventilation introduction it was 24.1 ± 5.5 years. All were receiving continuous ventilation support, 27 with non-invasive positive pressure ventilation and 28 with tracheal intermittent positive pressure ventilation. Thirty-eight were receiving β-blockers or a renin-angiotensin system inhibitor, while 9 were free from those agents. Forty had maintained oral nutrition. The 55 analyzed patients had survived into their 40s by receiving multidisciplinary intervention. Our findings emphasize the need of future studies to investigate disease modifiers and the mechanism of long-term survival. In addition, establishment of a worldwide care standard with focus on quality of life for adult males with DMD is important.

A clinical and pathological study of a Japanese case of Amyotrophic Lateral Sclerosis/Parkinsonism-Dementia Complex with family history.

Abstract. This report concerns a Japanese family with neuropathological findings consistent with amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) in the Island of Guam. The proband was a 68-year-old woman with an 8-year history of parkinsonism which was followed by psychiatric symptoms and neurogenic amyotrophy 5 years after the onset. She had a family history of parkinsonism associated with dementia in all of her three siblings. They grew up in the Hobara village, a focus of amyotrophic lateral sclerosis in the Kii Peninsula of Japan in their childhood. Their parents were not consanguineous nor natives of the Kii Peninsula. The brain weight was 1040 g and there were mild frontal lobe atrophy, moderate atrophy of pes hippocampi, decoloration of the substantia nigra and locus coeruleus, and atrophy of the anterior root of the spinal cord. The microscopic examinations revealed degeneration of CA1 portion of the hippocampus to the parahippocampus gyrus, substantia nigra, locus coeruleus and spinal anterior horn with Bunina bodies. The spinal pyramidal tracts also mildly degenerated. Neurofibrillary tangles (NFT) were observed in the cerebral cortex, especially in the cortices from hippocampus to lateral occipitotemporal gyri, basal nucleus of Mynert, basal ganglia, thalamus, substantia nigra and widespread regions of the central nervous system through the brainstem to spinal cord including the nucleus of Onufrowitcz. In spite of a small amount of the senile plaques in the cerebral cortex and Lewy bodies in the substantia nigra and locus coeruleus, abundant NFT were distributed mainly in the third layer of the cerebral cortex, which is the characteristic feature of ALS/PDC. Thus, this was likely to be an ALS/PDC case outside the Guam Island. A tau mutation was not found on DNA analysis.

Muscle development in healthy children evaluated by bioelectrical impedance analysis

OBJECTIVES This study aimed to use bioelectrical impedance analysis (BIA) to generate a new muscle density index (MDI), the MDI_BIA, to evaluate muscle development, and to demonstrate the changes that occur in the BIA-based muscle cross-sectional area index (MCAI_BIA) that accompany growth. We also sought to determine the traceability of chronological changes in the MDI_BIA and MCAI_BIA. METHODS Healthy children (n=112) aged 8.68±3.16years (0.33-14.00years) underwent bioelectrical impedance (BI) measurements of their upper arms, thighs, and lower legs. The MDI_BIA and MCAI_BIA were calculated, and cross-sectional investigations were conducted into the changes in these indices that accompanied growth. Data collected after 1.10±0.08years from 45 participants determined the traceability of the chronological changes in the MDI_BIA and MCAI_BIA. RESULTS The MDI_BIA and MCAI_BIA were significantly positively correlated with age and height at all locations (P<0.01). The relationships between the locations and the MDI_BIA and MCAI_BIA differed, indicating that these indices evaluated the muscles from different perspectives. Except for the upper arm MDI_BIA, both indices at all locations regardless of age, showed significant chronological increases after an average period of 1.10years. CONCLUSIONS The MDI_BIA and MCAI_BIA were significantly correlated with age and height in healthy children, and they showed significant chronological increases. Hence, these indices could be used to represent muscle development and muscle mass increases. BIA is non-invasive, convenient, and economical and it may be useful in evaluating muscle development and muscle cross-sectional areas in children.

Immunohistochemical localization of spatacsin in α‐synucleinopathies

Spatacsin (SPG11) is a major mutated gene in autosomal recessive spastic paraplegia with thin corpus callosum (ARHSP‐TCC) and is responsible for juvenile Parkinsonism. To elucidate the role of spatacsin in the pathogenesis of α‐synucleinopathies, an immunohistochemical investigation was performed on the brain of patients with Parkinsons disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA) using anti‐spatacsin antibody. In PD, Lewy bodies (LBs) in the brain stem were positive for spatacsin. These LBs showed intense staining in their peripheral portions and occasionally in the central cores. Lewy neurites were also spatacsin‐positive. In DLB, cortical LBs were immunolabeled by spatacsin. In MSA, glial cytoplasmic inclusions (GCI) and a small fraction of neuronal cytoplasmic inclusions (NCI) were positive for spatacsin. The widespread accumulation of spatacsin observed in pathologic α‐synuclein‐containing inclusions suggests that spatacsin may be involved in the pathogenesis of α‐synucleinopathies.

Analysis using histograms of muscle CT images in patients with Duchenne muscular dystrophy

We showed that the shape of the thigh CT value histogram, which was reflecting muscle and fat, changed with the disease progression in a patient with Duchenne muscular dystrophy, and this shape of the histogram will employ a new analytical method. CT images of the middle part of the thigh were acquired in a patient with Duchenne muscular dystrophy once a year from 6 to 11 years of age. Regions apparently corresponding to subcutaneous fat, bone and bone marrow were manually excluded, and the CT values were calculated to prepare histograms. His motor disability was also evaluated employing Vignos functional rating scale. A single peak was noted in the muscle CT value range in the histogram at the youngest age. The muscle-to-fat ratio in muscle decreased with the worsening of his disease disability level and the peak of the histogram shifted from the muscle to the fat CT value.

Clinico-pathological study of a case of familial parkinsonism with striatal degeneration

Abstract. The clinico-pathological study of a new type of familial parkinsonism with striatal degeneration is reported. The inheritance mode was autosomal recessive, and three out of four offspring of married cousins developed parkinsonism in their early adulthood. Their clinical signs were rigidity, bradykinesia, postural instability and dysarthria. These symptoms were slowly progressive and responsive to levodopa therapy to a variable degree. On cerebral magnetic resonance imaging, T2 and proton density-weighted images showed hyperintensity in the bilateral putamina. The neuropathological study of one case revealed atrophy of the bilateral putamina and caudate nuclei, and a severe neuronal loss and gliosis in the putamina. Patchy mosaicism of normal and degenerated tissue was observed in the putamina. A similar mode of the degeneration was mildly seen in the caudate nuclei. The substantia nigra showed atrophy of the pars reticulata, and mild to moderate neuronal loss of the pars compacta with rostral dominance, but no Lewy bodies were observed. These neuropathological findings differed from those of Parkinsons disease or juvenile parkinsonism, but mimic to those of X-linked dystonia parkinsonism (Lubag). It seems that this familial bilateral striatal degeneration is a new variant of familial parkinsonism.