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Biomedical subjects

I Nonaka

Publications and source records attributed to I Nonaka.

At least 343 records · Page 19Linked to original sources

Muscle pathology in Marinesco-Sjögren syndrome.

Three of 4 adult patients with Marinesco-Sjögren syndrome (MSS; 2 males and 2 females, aged 26-31 years) in 2 families became non-ambulant because of slowly progressive muscular weakness rather than cerebellar ataxia. Other clinical features in these 4 patients were typical for MSS: bilateral cataracts from infancy, mental retardation, severe cerebellar atrophy, multiple skeletal abnormalities and hypergonadotropic hypogonadism. EMG demonstrated a myopathic pattern and serum CK was mildly elevated. Muscle biopsies from these 3 patients showed myopathic changes including a marked variation in fiber size, an increased number of fibers with centralized nuclei, and scattered necrotic and regenerating fibers. Fiber type analysis with myosin ATPase staining showed type 1 fiber predominance, type 2B fiber deficiency and mild increase in type 2C fibers. Muscle biopsy changes and the clinical course indicate that our MSS patients suffered from a chronic dystrophic process similar to that in congenital muscular dystrophy.

Adenosine Triphosphatases↗

Focal cytochrome c oxidase deficiency in various neuromuscular diseases.

To determine whether focal cytochrome c oxidase (CCO) deficiency characterized by scattered fibers with absent CCO activity among normal fibers was a specific finding for mitochondrial myopathies, we studied 389 muscle biopsies from various neuromuscular diseases other than mitochondrial myopathies. Focal CCO deficiency was found in 14 biopsies: 5 of 26 patients with myotonic dystrophy, 3 of 19 with nemaline myopathy, 1 of 7 with distal myopathy with rimmed vacuole formation, 3 of 22 with limb-girdle muscular dystrophy, 1 of 9 with amyotrophic lateral sclerosis, one of 79 with Duchenne muscular dystrophy. Focal CCO deficiency is known to be a crucial finding for chronic progressive external ophthalmoplegia, but it can also be seen in a variety of other neuromuscular disorders, probably as a secondarily induced phenomenon.

Biopsy↗

Tissue specificity in cytochrome c oxidase deficient myopathy.

Biopsied muscles were treated in 2 ways to demonstrate cytochrome c oxidase (CCO) activity on electron microscopy: (1) one to several muscle fibers were teased off the biopsy in buffer solution after glutaraldehyde fixation, (2) 20-30-microns thick cryostat sections were placed on precooled glass slides and fixed in glutaraldehyde solution at room temperature. After rinsing in buffer, the teased fibers and cryostat sections were stained with cytochrome c oxidase. In both procedures, almost all mitochondria in control muscle fibers stained positively. In CCO deficiency, the enzyme activity differed from tissue to tissue indicating marked tissue specificity. In the fatal infantile form enzyme activity in muscle fibers was absent, but present in fibroblasts, endothelial cells and smooth muscle arterial cells. The enzyme activity in other forms differed from cell to cell, but individual mitochondria in a given cell examined in cross-section showed uniform CCO activity, indicating that there was no intracellular mosaicism of enzyme positive and negative mitochondria.

Adolescent↗

Immunochemical study of connectin (titin) in neuromuscular diseases using a monoclonal antibody: connectin is degraded extensively in Duchenne muscular dystrophy.

Connectin (also called titin) is a myofibrillar elastic filament which links a thick filament to a neighbouring Z line in a sarcomere and thus contributes significantly to the elastic property of myofibrils. In the present study, the degradation state of connectin in biopsied skeletal muscles from various neuromuscular diseases was investigated by Western blot analysis using a monoclonal antibody which reacts extensively with the degradation products of connectin. In Duchenne muscular dystrophy (DMD), connectin was degraded progressively and relentlessly after 5 years of age. In Becker muscular dystrophy, degradation of connectin was much less than in DMD. Connectin was well preserved in normal controls, and was only minimally degraded in Charcot-Marie-Tooth disease, amyotrophic lateral sclerosis, limb girdle muscular dystrophy and myotonic dystrophy, even when the biopsied muscles showed a similar degree of weakness as those of DMD. The degradation of connectin, even though secondary, is presumed to play an important role in the pathogenesis of myofibrillar degeneration in DMD.

Adolescent↗

Immunochemical analysis of alpha-actinin of nemaline myopathy after two-dimensional electrophoresis.

We analyzed alpha-actinin from human skeletal muscle by immunoblotting after two-dimensional electrophoresis. A monoclonal antibody, S alpha 5-17, was established after immunization in Balb/c mouse with crude alpha-actinin fraction from human soleus muscle. Western blotting and indirect immunofluorescence microscopy revealed that the antibody reacted selectively with alpha-actinin from human skeletal muscle and stained in a manner equivalent to that of type 1, 2A, 2B and 2C myofibers and cardiac atrial and ventricular muscles. No reactivity was observed in the arterial smooth muscle layer or in the central and peripheral nervous systems. The antibody exhibited 2 spots with different isoelectric points in a range more basic than that of actin upon immunoblotting after two-dimensional gel electrophoresis, suggesting the presence of 2 variants of alpha-actinin in human skeletal muscle. Analysis of type 2B-deficient muscle with nemaline myopathy or central core disease revealed that type 2B myofibers contained the basic variant, while type 1 and 2A myofibers contained only the acidic variant. Immunoblots performed after two-dimensional gel electrophoresis of muscles with nemaline myopathy revealed alpha-actinin variants indistinguishable from those of control muscles.

Actinin↗

Muscle histochemistry in myotubular (centronuclear) myopathy.

We report the clinical and histochemical findings in 7 patients with myotubular (centronuclear) myopathy aged from 2 months to 32 years. The clinical symptoms varied from patient to patient. Three patients developed severe muscle weakness and hypotonia with respiratory distress from infancy, and 4 had muscle weakness from 2-5 years of age with no apparent delay in developmental milestones. In addition to an increased number of fibers with centrally placed nuclei, there were 3 other histochemical characteristics of this disorder, i.e., type 1 fiber predominance, type 1 fiber hypotrophy and type 2B fiber deficiency. Other histological findings included a peripheral halo in the sarcoplasm on NADH-TR staining and an increased number of undifferentiated type 2C fibers, indicating a delay in muscle fiber growth and differentiation due to a probable defective neural supply in the developing muscles.

Adult↗

Peripheral nerve involvement in Werdnig-Hoffmann disease.

The number of large myelinated axons was markedly decreased in almost all the intramuscular nerve bundles included in 32 muscle biopsies from patients with Werdnig-Hoffmann disease compared to that in normals. The morphometric analysis of peripheral nerves in 5 epon-embedded sections also showed a selective loss of larger myelinated fibers. The ultrastructural findings of the nerves were similar to those seen in Wallerian degeneration including axonal degeneration, myelin breakdown with phagocytosis, Schwann cell proliferation forming Schwann cell columns, axonal sprouting and probable remyelination. The earlier and more striking peripheral nerve involvement than that previously believed was not different from that seen in amyotrophic lateral sclerosis (ALS). The earlier damage to the peripheral nerves probably resulted from a degeneration of the anterior horn cells or anterior spinal roots as in ALS rather than from a dying-back process.

Amyotrophic Lateral Sclerosis↗

Dystrophin diagnosis: comparison of dystrophin abnormalities by immunofluorescence and immunoblot analyses.

Immunoblot characterization and immunofluorescence localization of dystrophin are presented for 76 human patients with various neuromuscular diseases. Normal dystrophin (shown by immunoblotting) was invariably visualized as a continuous, peripheral membrane immunostaining of myofibers. Biochemical abnormalities of dystrophin (either lower or higher molecular weight dystrophin) resulted in patchy, discontinuous immunostaining, suggesting that the abnormal dystrophin proteins are not capable of creating a complete membrane cytoskeleton network. There was a very strong correlation of clinical diagnoses with the type of dystrophin abnormality; all Duchenne muscular dystrophy patient muscle contained no detectable dystrophin, Becker muscular dystrophy patient muscle had clearly abnormal dystrophin, and unrelated diseases showed normal dystrophin. However, a single patient of five carrying the diagnosis of Fukuyama dystrophy showed no detectable dystrophin and thus appeared to be a Duchenne dystrophy patient by the biochemical assays. We know of no other case of a patient with a disease thought to be unrelated to Duchenne/Becker dystrophy yet demonstrating dystrophin deficiency. Based on the data presented, we conclude that immunofluorescence is the best technique for the detection of female carriers of Duchenne dystrophy, whereas immunoblotting appears superior for the prognostic diagnosis of Becker muscular dystrophy.

Amino Acid Sequence↗

Distal myopathy with rimmed vacuole formation. A follow-up study.

A long-term follow-up study of patients with familial distal myopathy with rimmed vacuole formation and a review of the literature indicates that the prognosis of the disorder was extremely poor as to daily life. Although the initial symptom appearing in early adulthood was muscular wasting and weakness in the legs, especially the distal muscles, severe generalized skeletal muscle involvement with sparing of the facial, extraocular, bulbar, intercostal and diaphragm muscles was recognized in the advanced stage. The disease is probably inherited as an autosomal recessive trait, while there is a considerable female preponderance, the female-to-male ratio being 2:1. The disorder is distinguishable from various types of distal myopathy on the basis of clinical and pathological findings, and other myopathies with rimmed vacuole formation, including inclusion body myositis, from a prognostic viewpoint.

Adult↗

Disproportionate deficiency of iron-sulfur clusters and subunits of complex I in mitochondrial encephalomyopathy.

To investigate the molecular abnormality in the mitochondria from various tissues of an autopsied patient exhibiting mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes, we have examined the enzymatic activity, iron-sulfur cluster, and subunit composition of the NADH-ubiquinone oxidoreductase (complex I). Rotenone-sensitive NADH-cytochrome c reductase activity was found to be decreased in all the tissues examined. A detailed study of the liver mitochondria has shown that NADH-ubiquinone oxidoreductase activity was greatly diminished. Analysis of the electron paramagnetic resonance spectra of the liver submitochondrial particles revealed a disproportionate deficiency of iron-sulfur clusters in the complex I segment of the respiratory chain. Signals from the clusters N-2 and N-3 diminished more drastically than those from clusters N-1b and N-4. Immunoblotting analysis showed that the 75-kD, 51-kD, and several other subunits were markedly diminished among multiple subunit polypeptides of complex I. These findings suggest that the underlying bases for mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes are defects, at least, in the complex I subunits containing a flavin and/or iron-sulfur cluster(s), which resulted in deficiencies of some iron-sulfur clusters.

Acidosis, Lactic↗

[Two cases of mitochondrial myopathy (focal cytochrome c oxidase deficiency), long-term follow-up on a diagnosis of ocular type myasthenia gravis].

Two patients (a 50-year-old and a 35-year-old men) with focal cytochrome c oxidase deficiency, manifesting ptosis and external ophthalmoplegia of 13 and 6 years' duration, respectively, were reported. Patient 1 (a 50-year-old male) had also slight muscular weakness of the proximal limb and neck flexor muscles. Diagnosis of myasthenia gravis had been made on the clinical findings including ptosis and external ophthalmoplegia, diurnal fluctuation of symptoms, and equivocal positive Tensilon test. However, waning phenomenon on repetitive nerve stimulation or elevation of titer of the anti-acetylcholine receptor antibody was not detected on both patients. Needle EMG showed mild myopathic changes. Finally, pathological and biochemical analyses of the biopsied muscles confirmed the diagnosis of mitochondrial myopathy (focal cytochrome c oxidase deficiency).

Adult↗

[Ultrastructural immunocytochemical localization of electron-transport enzymes in mitochondrial myopathy].

Ultrastructural localization of mitochondrial electron transport enzymes in biopsied muscle from a patient with mitochondrial myopathy was studied. We applied the immunoelectron microscopic technique using colloidal-gold labeled antibodies. The results demonstrated a very distinct and dense labeling by gold particles of complexes I, III, and IV in the inner mitochondrial membrane. The density of gold particles reacted to complex IV was cleanly decreased. This result was correlated with the decreased biochemical activity of complex IV. Labeling on the paracrystalline inclusions was substantially decreased in abnormal giant mitochondrial, but gold particles were extensively confined on the membrane of cristae surrounding the inclusions.

Adult↗

[A case of progressive myopathy with tubular aggregates].

Tubular aggregates (TA) are unusual intramuscular structures stained basophilic on hematoxilin and eosin (HE) staining and red on modified Gomori trichrome (GT) staining. The structures are said to be originated from sarcoplasmic reticulum and are collections of tubules with double membranes on electron microscopic studies. The TA are usually seen in biopsy muscles from patients with muscle pain and cramps but without muscle weakness, periodic paralysis or alcoholic myopathy. In addition, there are five reports on families with progressive myopathy and tubular aggregates in the literature. We presented here a 48-year-old postman without any family history, who had had progressive muscle weakness for 17 years. He had never noticed pain or cramps in his muscles, not taken any particular medicine, and not had regular alcoholic beverages. There was no ptosis, facial weakness, masticatory muscle weakness or dysphagia. Muscle wasting, started from the proximal part of four extremities had progressed to the distal part of them. He could not walk on heels or toes and walked with waddling gait. He stood up with Gowers' maneuver. Serum GOT, GPT and CK were elevated. EMG showed myogenic pattern and MCV was normal. The muscle biopsies were performed; the first one taken from quadriceps femoris muscle at 42 years old showed myopathic changes including marked variation in fiber sizes, with scattered necrotic fiber splitting and TA in type 2B fibers. The second biopsy from biceps brachii muscle at the age of 48 years, showed densely proliferated fibrous tissues, marked variation fiber sizes and scattered split fibers. The TA were rarely seen and type 2B fibers were decreased in number.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy↗

Maternal inheritance of deleted mitochondrial DNA in a family with mitochondrial myopathy.

Skeletal muscles from a mother and her daughter both with chronic progressive ophthalmoplegia were analyzed. Histological and biochemical analyses of their muscle samples showed typical features of this type of mitochondrial myopathy. Southern blot analysis revealed that, in both patients, there were two species of mitochondrial DNA (mtDNA): normal one and partially deleted one. The sizes of the deletion were different; the mutant mtDNAs from the mother and the daughter had about 2.5- and 5-kilobase deletions, respectively. The two mutant mtDNAs shared a common deleted region of 1.2-kilobase. However, both the start and the end of deletion were different between them, implying a novel mode of inheritance. This is the first report that the mutant mtDNA is responsible for the maternal inheritance of a human disease.

Adolescent↗

Immunostaining of skeletal and cardiac muscle surface membrane with antibody against Duchenne muscular dystrophy peptide.

Duchenne muscular dystrophy (DMD) is a debilitating X-linked muscle disease. We have used sequence information from complementary DNA clones, derived from the gene that is deleted in DMD patients, to generate an antiserum that stains the surface membrane of intact human and mouse skeletal muscle, but not that of DMD patients and mdx mice. Here we identify the protein reacting with this antiserum as a single component of relative molecular mass 210,000 (Mr = 210K) that fractionates with a low-ionic strength extract of intact human and mouse skeletal muscle. It is therefore distinct from the 400 K protein found in the heavy microsomal fraction of normal muscle and identified as a putative product of the DMD gene. We also analyse further the disease specificity of the antiserum. Positive staining is seen in normal controls, and in samples from patients with a wide range of muscular dystrophies other than DMD. Becker muscular dystrophy, which is allelically related to DMD, was the only other exception, and gave a sporadic staining pattern. The demonstration of a specific defect in the surface membrane of DMD muscle fibres substantiates the hypothesis that membrane lesions may initiate muscle degradation in DMD.

Animals↗

Findings in muscle in complex I (NADH coenzyme Q reductase) deficiency.

Thirteen of 15 patients with complex I deficiency had the multisystemic form, with strokelike episodes and other symptoms that fulfilled the diagnostic requirements for MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes), and 2 had only muscle fatigability and weakness, having the purely myopathic form. In the multisystemic form, 12 patients had ragged-red fibers. All multisystemic patients had myopathic histochemical abnormalities that consisted of mild to moderate variation in fiber size, disorganized intermyofibrillar networks, type 2 fiber atrophy, and an increased number of type 2C fibers. Five of 13 multisystemic patients had decreased cytochrome c oxidase (CCO) activity in extrafusal fibers, with sparing of intrafusal muscle fibers. In the myopathic form, pathological findings were similar to those in the multisystemic form. In addition to complex I and NADH dehydrogenase activities being decreased, the CCO activity was significantly decreased (less than 50% of control value) in 8 patients, especially when the disease was in its advanced stages, suggesting that CCO enzyme might be secondarily affected as the disease progresses.

Adolescent↗

Localization of ingensin in rat central nervous system and skeletal muscle.

A high molecular weight, fatty acid- and SDS-sensitive protease named ingensin was purified from rat brain in this study. The enzyme purified from rat brain has the same biochemical properties as those purified from other tissues, e.g., porcine skeletal muscle, human placenta, and rat liver in our laboratory, and rat skeletal muscle and bovine pituitary gland in other laboratories, independently. Immunoblot bands were detected in the same positions as those in the case of ingensin from rat liver. In addition, its topographical distribution was studied in rat brain and muscle by means of the immunohistochemical method. The cytoplasm of motor neurons of the spinal cord, pyramidal cells, and granular cells of the hippocampus, Purkinje cells, and glial cells were stained. Axons were stained. The cytoplasm of muscle was also stained, especially that of type 2 fibers.

Animals↗

alpha-Glucosidase isoenzymes in normal and acid maltase-deficient human skeletal muscles.

One acid alpha-glucosidase and two neutral alpha-glucosidases were separated from human skeletal muscle by DEAE-cellulose column chromatography. The appearance of the two human neutral alpha-glucosidase isoenzymes was found to be age dependent. We called them "fetal" and "adult" neutral alpha-glucosidases. The biochemical properties of the fetal and adult types of neutral alpha-glucosidases appeared to be similar to those previously reported for neutral alpha-glucosidases AB and C, respectively. The neutral alpha-glucosidase activity in the column eluate of the infantile acid maltase deficiency (AMD; 5-month-old) muscle was completely of the adult type, whereas 18% of the total neutral alpha-glucosidase activity in age-matched control muscle was of the fetal type. In contrast, the eluate of the late-onset AMD (32-year-old) muscle contained both the adult and fetal neutral alpha-glucosidases, 68 and 32%, respectively.

Adult↗