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Biomedical subjects

T Ibi

Publications and source records attributed to T Ibi.

At least 37 records · Page 2Linked to original sources

[Immunostaining of mitochondrial heat shock proteins (mtHSPs) in skeletal muscle fibers of mitochondrial cytopathy].

Expression of the mtHSPs (HSP60 and mtHSP70) was immunohistochemicall observed in biopsied limb muscles of genetically determined mitochondrial cytopathies (chronic progressive ophthalmoplegia 14, MELAS 4, limb girdle syndrome with the A-to-G transition at nt.3243 of tRNALeu(UUR), exertional myoglobinuria with multiple deletions of mtDNA 2, and Leber's hereditary optic neuropathy 2). mtHSP 70 and HSP 60 were strongly localized at ragged-red fibers. In strongly succinate dehydrogenase-reactive vessels of MELAS, mtHSP70 was expressed. GRP78 was expressed in the cytoplasmic body, which is often observed in this disorder. The present data suggest that expression of mtHSPs may reflect increased numbers of mitochondria, an impairment of assembly of mitochondrial proteins encoded by the genomic DNA and abnormal mitochondrial DNA, and/or an impaired mitochondrial function due to recurrent oxygen radical attacks against mitochondria.

Chaperonin 60↗

[Immunostaining of anti-Bcl-2 antibody in diseased human muscles].

Immunostaining of Bcl-2 protein which represses apoptosis was performed on 178 biopsied human pathologic muscles and 10 control muscles by the ABC method using two monoclonal anti-Bcl-2 antibodies. Bcl-2 in control muscles was positive mainly in nuclear membrane and cytoplasm in type 2 fibers (especially type 2B fibers), and negative in type 1 fibers. In myopathies, it was not expressed in type 2C (regenerating) fibers, and its expression in atrophic fibers such as forming pyknotic nuclear clumps was strong. In inflammatory myopathies, expression was observed in infiltrating lymphocytes, and especially in dermatomyositis in atrophic fibers facing perimysium. In mitochondrial myopathies, the positivity was observed only in type 2 ragged-red fibers. In muscles of neurogenic disorders, both small angulated fibers and atrophic grouped fibers were strongly positive. Western blot analysis using anti-Bcl-2 antibody showed a single band at 26 kDa in control and diseased skeletal muscles. Compared to immunostaining of Fas antigen in serial sections, both Bcl-2 and Fas were expressed in same atrophic fibers in distal myopathy with rimmed vacuoles. In myotonic dystrophy, they were often expressed in type 2 fibers containing internal nucleus. In carriers of Duchenne dystrophy, Fas-positive but Bcl-2 negative fibers were observed in same dystrophin-negative fibers. In conclusion, expression of Bcl-2 in skeletal muscles might suggest that Bcl-2 plays a role on surviving muscle fibers.

Apoptosis↗

Clinical and neuropathological features of a neurodegenerative disorder in the central nervous system with progressive head drooping (Kubisagari).

The clinical and neuropathological features of a case of a neurodegenerative disorder with pronounced and progressive head drooping, in Japanese Kubisagari, are reported. This female patient died at the age of 72 years after an approximately 20-year history of peculiar posture with progressive head drooping (Kubisagari) and lordosis (bowed posture), parkinsonism, dysphonia and slight muscle wasting of the face, tongue, neck, and distal portions of the upper extremities. She did not display mental deterioration until the terminal stage of the illness. A simple macroscopic inspection formalin-fixed sections of the central nervous system (CNS) showed prominent atrophic frontal and temporal lobes, brownish discoloration of the putamen and an atrophic pyramidal tract. Light microscopy revealed severe neuron loss with fibrillary gliosis at both the above-mentioned lobes and the putamen. Both the facial and hypoglossal nuclei had almost disappeared. Motor neurons in the spinal cord were moderately to markedly decreased. Neither Bunina nor Lewy bodies, senile plaque, nor Pick's argyrophilic neuronal inclusions were observed, but very occasionally ubiquitin-positive neurons were found in the temporal cortex. In conclusion, the hitherto-unrecognized neuropathological findings in the CNS corresponding to progressive head drooping (Kubisagari) suggest that this is a neurodegenerative disorder of the CNS, possibly an atypical form of amyotrophic lateral sclerosis.

Aged↗

[Pathophysiology on the disorder of neuromuscular transmission defects].

Neuromuscular transmission defects are often puzzling but challenging diseases for the pediatric and adult neurologists. Some of these disorders entail severe or even life-threatening disability: Most are treatable, but effective therapy requires precise diagnosis sometimes difficult to make especially in congenital defects. The diagnosis rests on the combination of clinical data, the electromyogram and additional studies that may include microelectrode analysis of neuromuscular transmission, ultrastructural and cytochemical studies of neuromuscular junction (NMJ) and biochemical/molecular genetic studies on muscle specimens. Understandably, these studies often depend on the collaboration of several investigators. In each myasthenic disorder, an abnormality affects neuromuscular transmission directly or causes secondary derangements that eventually affects transmission. Namely, lesions of both the presynaptic and/or postsynaptic area manifest a variety of clinical findings. Here was discussed the pathophysiology on myasthenia gravis and Lambert-Eaton myasthenic syndrome of abnormal autoimmunity, congenital myasthenic syndromes of a chromosomal defect, and poisoning of organophosphorus, botulism and some other toxins.

Adult↗

[Corticosteroid responsive inflammatory myopathy with autoantibody against Golgi apparatus].

A 51-year-old woman of progressive myopathy predominantly involving proximal groups of limb-muscle was reported. Serum enzymes originating from the skeletal muscle always remained within normal range, and a positive autoantibody against Golgi apparatus and the SS-A (Ro) antibody in serum were noted. In muscle biopsy performed twice, extensive degenerating/regenerating fibers and sparce inflammatory cells between connective tissue elements in light microscopy, and disrupted lamellar structure of Golgi apparatus in electron microscopy were observed. Corticosteroid therapy was markedly effective. In the present case of a "so-called" limb-girdle syndrome, humoral autoantibodies, especially against Golgi apparatus, could induce a metabolic disturbance in the muscle fiber.

Autoantibodies↗

[Expression of MHC and cell adhesion molecules in muscular sarcoidosis].

Biopsied skeletal muscles from 5 patients with muscular sarcoidosis (nodular type; 1, and myopathic type; 4) were immunocytochemically examined. All biopsies presented granulomatous changes. Atrophic or regenerating muscle fibers adjacent to granuloma demonstrated compression or ischemic changes. In the center of the granuloma, CD68+ epitheloid cells and giant cells, and CD4+ T cells were localized. At the periphery of the granuloma, CD4+ T cells, CD8+ T cells, CD20+ B cells, and CD68+ macrophages were found. Expression of HLA-A,B,C was diffuse in the muscle fibers. Expression of HLA-DR and ICAM-1 was more prominent near the granuloma or perifascicular fibers, and that of LFA-3 was moderate in those lesions. VCAM-1 was expressed in endothelial cells and macrophages near the granuloma. Those findings indicate that interferon-gamma or TNF-alpha produced by infiltrating inflammatory cells may induce expression of these immunologic markers or adhesion molecules. Immunocytochemical differences between the nodular and myopathic forms of sarcoidosis are not evident, but either localization or abundance of granuloma in muscle bulks is relevant to weakness or atrophy of clinically affected muscle.

Aged↗

[Immunostaining of anti-Fas IgG1 antibody in diseased human muscle].

Immunostaining of the Fas antigen using the anti-Fas IgG1 antibody was performed on biopsied human diseased muscles. The immunostaining showed negative results in the control muscles. In dystrophinopathy [DMD and BMD], positivity was seen mainly in type 2 fibers with no correlation to the opaque fibers and histochemical Ca2+ loading fibers in DMD. In DMD carriers, a relative correlation was seen between dystrophin-negative and Fas-positive fibers. In distal myopathy with rimmed vacuoles, fibers with positive staining in the vacuoles but negative in their membranes were seen at high frequency. In FSH, a very low frequency of positivity was seen. And in myotonic dystrophy, positivity was seen in the type 2 fibers containing the internal nuclei. In inflammatory myopathies, strong positivity was seen in the medium size fibers, and mild to moderate positivity in the fibers facing the perimysium. In neurogenic muscular disorders, fibers with concave borders or highly atrophic fibers showed Fas-positivity. In conclusion, there was no disease-specific Fas reaction in the human pathologic muscle samples, but the high positivity was apparent in some myopathies. This fact of Fas antigen would reflect a pathologic state in the skeletal muscle.

Antibodies↗

[Expression of the heat shock protein 70 in inflammatory myopathies].

Heat shock protein 70 (HSP 70) expression was immunohistochemically observed in diseased muscle fibers of 35 patients with dermatomyositis (DM) and 7 with polymyositis (PM). In DM, HSP 70 was localized in the sarcoplasm of type 1 fibers adjacent to the small vessels showing deposits of complement components in 13 patients and in the atrophic fibers at perifascicular regions in 7. HSP 70 was also expressed more preferentially in the small vessels rather than in the sarcoplasm in 13 DM patients. In PM, the expression of HSP 70 was blurred in all fibers including non-necrotic fibers invaded by T cells. In conclusion, HSP 70 is likely more frequently to be expressed in the sarcoplasm of DM than PM due to probable ischemic insults.

Dermatomyositis↗

Multiplicity of abnormal dystrophin in Becker muscular dystrophy. A Becker muscular dystrophy gene frequently produced two smaller sizes of dystrophin.

Dystrophin is a muscle cytoskeletal protein with a molecular mass (MM) of approximately 420 kDa and an isoelectric point (pI) of approximately 5.5, which is abnormal in size and/or abundance in Becker muscular dystrophy (BMD). We investigated the abnormality of dystrophin molecule in muscles biopsied from 23 BMD patients using the two-dimensional gel electrophoresis (TDGE). We found 7 protein spots which reacted specifically with the monoclonal anti-dystrophin antibody (mAb) A1C raised against N-terminal domain of the normal dystrophin. These spots were focused on the two-dimensional gel at the same position as the normal dystrophin (#1), at the position with MM approximately 480 kDa/pI approximately 5.35 (#2), the position with MM approximately 400-330 kDa/pI approximately 5.51-5.47 (#3), the position with MM approximately 300 kDa/pI approximately 5.4 (#4), the position with MM approximately 235-250 kDa/pI approximately 5.53-5.5 (#5), the position with MM approximately 165 kDa/pI approximately 6.0 (#6), and the position with MM approximately 160 kDa/pI approximately 5.75 (#7). These spots were classified into five patterns in individuals, that is, #1 alone in 3 patients, #3 alone in 1, the combination of #3 and 5 in 17, the combination of #1, 3 and 5 in 1 and the combination of #1, 2, 4, 6 and 7 in 1. The combination of #3 and 5 was observed in 17 of 23 patients (75%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Immunostaining of dystrophin and utrophin in skeletal muscle of dystrophinopathies.

Immunostaining of biopsied skeletal muscle of 4 Duchenne (DMD), 12 Becker muscular dystrophy (BMD) and 3 DMD carriers' was performed using monoclonal antibodies against dystrophin and utrophin. In DMD, dystrophin-negative staining was observed except for revertant fibers which showed different stain patterns for each antibody. In 7 BMDs, there was faint/patchy stain in cases of deletion between exons 45-52, while in one case there was deletion between exons 12-17 and no stain was noted relevant to the deletion site. Moreover, in 2 cases of undetectable deletion, antibodies which recognize a terminal portion of the C-terminal domain revealed the absent stain. In DMD, the utrophin-positive fibers corresponded to dystrophin-negative fibers. In BMD, this relationship did not necessarily occur in each fiber. In DMD carriers, a cluster of dystrophin-negative fibers which was positive for utrophin were prominent. In dystrophinopathy, the immunostaining of dystrophin and utrophin is useful, in combination with dystrophin gene analysis to make a definite diagnosis.

Adolescent↗

[Acquired unilateral blepharoptosis by wearing contact-lenses in young adult women].

Four young unmarried women developed unilateral non-fluctuating blepharoptosis by wearing contact-lenses. Past and family histories were unremarkable. Blepharoptosis insidiously occurred within a few years after wearing lenses. Contralateral lid was quite normal. No abnormalities was observed in pupils, extraocular muscles, ocular positioning and other systems. So far recognized causes of blepharoptosis were ruled out through extensive clinical and laboratory observations. Improvement was insufficient even after wearing lenses off. Pathogenesis is probably due to repeated minor trauma to the levator palpebral muscle and its tendon secondary to frequent wearing on/off contact-lenses.

Adult↗

Progressive external ophthalmoplegia and myositis.

We reported a senile male patient with progressive external ophthalmoplegia (PEO) and myositis. The ophthalmoplegia was severe, but other neuromuscular features were nearly normal. Muscle enzymes in serum were moderately elevated. Autoimmune, endocrinological or malignant diseases were not observed during the previous 4 years. Pathology of non-weak limb muscles biopsied twice was consistent with active inflammatory myopathy. The ragged-red or cytochrome c oxidase-negative fibers, which are a hallmark of mitochondrial myopathy with PEO, were not increased in comparison with age-matched control muscles. Analysis of mitochondrial DNA in muscle by the Southern blot method did not reveal any deletions. It was concluded that the inflammatory myopathy, myositis clinically localized at the ocular muscles, is an important and distinct disorder in PEO.

Aged↗

Increased mitochondrial DNA deletions in the skeletal muscle of myotonic dystrophy.

Mitochondrial abnormality in the skeletal muscles of 13 patients with myotonic dystrophy was analyzed by both histochemical and molecular biologic methods. Nine of 13 patients had ragged-red fibers (50 +/- 116 per 10,000 muscle fibers, mean +/- SD), and 10 patients had cytochrome c oxidase-negative fibers (41 +/- 90 per 10,000 muscle fibers). Southern blot analysis detected no mitochondrial DNA deletions, while PCR revealed multiple mitochondrial DNA deletions in all the specimens. Direct sequencing of one of the deleted mitochondrial DNAs disclosed that the junctional sequence of a 3,460-bp deletion involved a 6-bp directly repeated sequence (5'-TAGAAG-3') flanked by C-rich regions located on the CO3 gene and the ND5 gene. Quantitative analysis of PCR amplified deleted mitochondrial DNAs revealed that the amount of deleted mitochondrial DNAs had positive correlation both with the frequencies of ragged-red fibers and cytochrome c oxidase-negative fibers. Although deleted mitochondrial DNAs were observed even in controls above age 30, the mean amount of deleted mitochondrial DNAs in patients with myotonic dystrophy was significantly higher than in controls. Moreover, the increase of deleted mitochondrial DNAs with aging was more marked in myotonic dystrophy than in controls. These results suggest that increased mitochondrial DNA deletions and consequent impairment of mitochondrial function contribute to the pathophysiology of myotonic dystrophy.

Adolescent↗

[A mother and her son with autosomal dominant bulbar spinal muscular atrophy].

We reported a 49-year-old mother and her 28-year-old son with autosomal dominantly inherited bulbar spinal muscular atrophy (AD-BSMA). They showed progressive bulbar paresis, muscle wasting and weakness dominant in the proximal groups of limb muscles, and finger tremor. Onset of illness was in adult life. In laboratory examinations, elevated creatine kinase in serum and neurogenic changes either in EMG or muscle biopsy were noted. The son had neither gynecomastia nor abnormal sexual hormone levels which were observed in the sex-linked recessive bulbar spinal muscular atrophy (SR-BSMA). Elongation due to the CAG repeats at the androgen receptor gene of the X chromosome in SR-BSMA was not detected. In conclusion, it is clear that AD-BSMA is different from SR-BSMA on the basis of clinical and genetical aspects.

Adult↗

[Quantitative skeletal muscle pathology of aging regarding ragged-red fibers and cytochrome c oxidase-negative fibers].

A statistical analysis of mitochondrial abnormality of aging in human skeletal muscle fibers was performed. Sixty one muscle samples were obtained from patients with acute medical illness autopsied strictly within 2 hours after death, or with orthopedic or surgical diseases biopsied with informed consents. The patients aged from 16 to 89, averaging 58 +/- 21 years in males and 21 to 92, averaging 55 +/- 20 years in females. Sections were stained by modified Gomori's trichrome, succinate dehydrogenase and cytochrome c oxidase-negative [CCO(-)] fibers approximately in 10,000 fibers in each muscle were evaluated. Both RRF and CCO (-) fibers were not observed below the fourth decade, but sequentially increased with age, especially after the seventh decade. The incidence of CCO (-) fibers was higher than that of RRF. RRF did not necessarily correspond to CCO (-) fibers. The present quantitative pathological result is a useful tool to evaluate the mitochondrial function in fresh human skeletal muscles by the age.

Adolescent↗

Direct DNA sequencing from colony: analysis of multiple deletions of mitochondrial genome.

We have developed a rapid and efficient nucleotide sequencing technique, named the colony direct sequencing method, which combines both the conventional cloning method for picking up a single gene and the polymerase chain reaction (PCR) method for amplifying the gene directly from a colony. In the present study, the colony direct PCR product was used both for identification of the DNA insert and for nucleotide sequencing by an automated DNA analysis system. A nucleotide sequence of 300 to 400 bp could be determined within 13 h after picking the bacterial colonies on LB medium plates. We applied this method to sequencing of junctional regions of multiple deleted mtDNAs in two siblings with inherited recurrent myoglobinuria. Mitochondrial DNA fragments with deletions were amplified by PCR and then cloned into plasmids. Among 48 white colonies propagated on LB medium plates, nine different clones were identified by PCR directly from colonies. Determination of six different junctional sequences disclosed involvement of directly repeated sequences of 2 to 12 bp in length on each side of the deletions. We believe that the colony direct sequencing method will be a powerful tool in molecular genetics for identification of a single gene among polymorphic DNAs.

Adenosine Triphosphatases↗

Mitochondrial DNA deletions in inherited recurrent myoglobinuria.

We describe two brothers with inherited recurrent exertional myoglobinuria and alcohol intolerance associated with distinct morphological abnormalities of muscle mitochondria and multiple deletions of muscle mitochondrial DNA. Patient 1 (26 years old) and Patient 2 (21 years old) had recurrent episodes of myoglobinuria provoked by strenuous exercise or alcohol intake, from the age of 18 years. Although their serum lactate and pyruvate levels were normal at rest, they were significantly elevated by aerobic exercise. Histochemistry of their biopsied limb muscles showed ragged-red fibers and cytochrome c oxidase-negative fibers as well as degenerating and regenerating fibers. Electron microscopy showed pronounced accumulation of abnormal mitochondria containing paracrystalline inclusions and moderate increases of glycogen particles. The enzyme activities of the electron-transfer complexes in the isolated muscle mitochondria of Patient 2 were within normal ranges. Southern blot analysis revealed multiple deletions of mitochondrial DNA, some of which were common between the patients. Polymerase chain reaction of their muscle mitochondrial DNA detected multiple abnormal fragments indicating mitochondrial DNA deletions. We propose that a defect of the mitochondrial energy-transducing system due to multiple mitochondrial DNA deletions is a novel genetic cause of inherited recurrent myoglobinuria.

Adult↗