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M Osame

Publications and source records attributed to M Osame.

At least 199 records · Page 11Linked to original sources

[Chronic interstitial pneumonia and crescentic glomerulonephritis associated with perinuclear antineutrophil cytoplasmic antibodies].

We examined a 72-year-old man suffering from chronic interstitial pneumonia with crescentic glomerulonephritis associated with perinuclear antineutrophil cytoplasmic antibodies (P-ANCA). Ten years before admission, he was given a diagnosis of interstitial pneumonia, but received no medication. He was admitted to our hospital because of a high fever and back pain. Antibiotics were used, but without success. The serum P-ANCA titer was high, and examination of a kidney biopsy specimen showed crescentic glomerulonephritis. Computed tomography of the chest showed that the lungs had a honecomblike appearance, and examination of a specimen obtained by transbronchial lung biopsy showed interstitial fibrosis. This case shows that interstitial pneumonia can be associated with P-ANCA. It is important to be a wore that crescentic glomerulonephritis associated with P-ANCA can develop in patients with interstitial pneumonia.

Aged↗

[A case of tuberculous abscess in the chest wall close to the thickening pleural lesion following tuberculous pleuritis].

A 33-year-old woman with a history of right tuberculous pleuritis was successfully treated in December 1992 by administration of anti-tuberculous drugs, she demonstrated residual localized pleural thickening on chest computed tomography (CT) and gradually developed a subcutaneous mass in the right chest which became apparent in March 1993. In September, chest CT revealed a periocostal abscess in the right anterior chest wall close to the localized pleural thickening. The patient was diagnosed with tuberculous abscess in the right chest wall on confirmation of acid-fast bacilli in a needle aspiration material of the abscess, and was referred to our hospital. Anti-tuberculous chemotherapy was continued but the chest abscess grew, so on January 28, 1994 she underwent a resection of the abscess, the third costal cartilage and bone, and the parietal pleural lesion connected to the abscess. Histopathological examination showed that the abscess and parietal pleural lesion were compatible with tuberculosis, i.e. both lesions consisted of caseous necrosis and epitheloid cell granuloma, but acid-fast bacilli were not demonstrated in both lesions. After one year of postoperative anti-tuberculous chemotherapy, she was followed without any therapy for 3 years and there has been no recurrence to date. When a localized thickening pleural lesion remains after tuberculous pleuritis, complication of tuberculous abscess in the chest wall should be considered.

Abscess↗

[A case of rapidly progressive HTLV-I-associated myelopathy (HAM)].

We report a 65-year-old woman with HAM who showed rapid progression of the clinical symptoms. The initial symptom was lumbago and she became unable to walk within 4 months after the onset of the lumbago. When seen on admission, she had flaccid paraplegia and areflexia was seen in the lower extremities with positive Babinski and Chaddock reflexes. She had numbness below the level of the navel, vibratory sensation was decreased in both lower limbs, and there was a hyperesthesic zone at the tenth thoracic vertebral level. She had a difficulty in urination and defecation. Laboratory examination revealed elevated anti-HTLV-I antibody titers both in serum (4,096x by PA method) and in cerebrospinal fluid (CSF) (4,096x). The levels of IgG and neopterin in CSF were also increased to 16.6 mg/dl (normal: < 5 mg/dl) and 360.3 pmol/ml (normal: < 30 pmol/ml), respectively. HTLV-I messenger RNA positive cells were detected in 0.1% to 0.01% of cells in CSF by in situ hybridization using an oligonucleotide probe labelled with alkaline phosphatase. Spinal cord MRI detected neither spinal cord compression nor vascular diseases. She was treated with 1,000 mg methylprednisolone for 3 days intravenously, followed by 60 mg oral prednisolone therapy. In several days after receiving the treatments, her muscle tonus became spastic and deep tendon reflexes in the legs became brisk. The hyperesthesia at the tenth thoracic vertebral level and numbness below the level of the navel were also gradually improved. Subsequently, her clinical features were consistant with those of the typical HAM. Therefore, the patient was diagnosed as rapidly progressive HAM. The initial phase of rapidly progressive HAM patients had been described only from clinical history. These patients had common characteristic clinical features, such as older age at onset, relatively severe motor dysfunction, high titers of anti-HTLV-I antibody in CSF, and increased levels of neopterin and IgG in CSF, when compared with those of other HAM patients. The clinical course and laboratory findings in the present patient were compatible with those in the previous cases reported as rapidly progressive HAM. This patient showed flaccid paraplegia and areflexia which have rarely been seen in HAM patients. However, these symptoms were changed to spastic and hyperactive after prednisolone therapy. We speculate that inflammation in the spinal cord in this patient was severe enough to spread to the dorsal root, and disturbed the afferent pathway from the peripheral to the central nervous system. This inflammatory reaction might be suppressed by prednisolone to facilitate the recovery of the afferent pathway, which led to the typical clinical symptoms of HAM.

Aged↗

[Familial hyperkalemic periodic paralysis: a brief review of the adult human skeletal muscle sodium channel and the application of LA-PCR to the SCN4A gene analysis].

Recent work has revealed that familial hyperkalemic periodic paralysis, paramyotonia congenita and other non-dystrophic myotonias result from point mutations in the gene encoding the alpha-subunit of the adult human skeletal muscle sodium channel (SCN4A). Sodium channel myotonias are a diverse group of skeletal muscle disorders that share a common pathophysiological mechanism: all are caused by impaired rapid inactivation of skeletal muscle sodium channel. Clinical studies, pharmacology, electrophysiology and molecular genetics have contributed to an elucidation of the genotype-phenotype correlation within these disorders. This article briefly reviews recent advances in our understanding of skeletal muscle sodium channel and sodium channel myotonias. The application of LA-PCR to the SCN4A gene analysis is also referred.

Adult↗

[Recent progress of molecular immunology on inflammatory myopathy].

The pathogenesis of polymyositis(PM), T-cell-mediated disease, and dermatomyositis(DM), humoral immunity-mediated disease, has not been clearly understood. Retroviruses(HIV, HTLV-I) may play a important role in some PM/DM patients. HTLV-I provirus was detected in infiltrating CD4+ lymphocytes, but not within the muscle fibers by PCR in situ hybridization. It is suggested that HTLV-I-associated PM is not due to direct, persistent infection of the muscle fiber by the virus, but to a T-cell-mediated immunological process triggered by the HTLV-I-infected cells. Inclusion body myositis(IBM) is characterized pathologically by vacuolated muscle fibers containing paired-helical filaments(PHFs) similar to Alzheimer-disease brain. Furthermore, prion protein and mRNA are abnormally accumulated in IBM muscle.

Autoimmunity↗

[Clinical investigation of three cases of pulmonary eosinophilic granuloma].

Patient 1: An 18-year-old woman was admitted to our hospital with pneumothorax. She had no history of smoking. Chest CT showed multiple cysts, and pulmonary eosinophilic granuloma was diagnosed by open lung biopsy. She recovered without therapy 3 months later and a chest CT taken at that time was normal. She began smoking, 3 years later, and bore two children. She is without recurrence after 8 years. Patient 2: A 23-year-old man was admitted to our hospital with pneumothorax. He had a smoking history (index = 180). Chest CT showed multiple cysts, and pulmonary eosinophilic granuloma was diagnosed by open lung biopsy. He stopped smoking and recovered without therapy one month later, and subsequently, his CT findings returned to normal. Two years later, he began smoking again, but has no relapse. Patient 3: A 21-year-old man was admitted to our hospital with pneumothorax. He had no history of smoking. A chest CT showed multiple cysts, and pulmonary eosinophilic granuloma was diagnosed by open lung biopsy. Diabetes insipidus was subsequently noted. Dyspnea persisted, and he recovered 4 months later after steroid treatment. He was without relapse 2 years later but the multiple cysts remained. We report three cases of pulmonary eosinophilic granuloma, and discuss their pertinent clinical features.

Adult↗

A kinetic comparative study on lymphocyte responses to superantigen and phytohemagglutinin: reciprocal presentation of superantigen on the surface of activated lymphocytes.

The kinetics of thymidine incorporation into fractionated T lymphocytes responding to bacterial superantigens were compared to those of cells activated by phytohemagglutinin (PHA). Evident differences between the kinetics of cell proliferation induced by PHA-P and staphylococcal enterotoxin B (SEB) emerged after Day 4 of culture. PHA-P-induced proliferative responses of peripheral blood mononuclear cells (PBMCs) and fractionated cells were apparent on Day 4 because of the presence of accessory cells in the initial cell suspensions. This gradually diminished in correlation with the decline of accessory cells in the cultures. The SEB-induced cell growth (PBMCs and CD4+ cells), however, continued until Day 9 of the culture. This finding suggests the reciprocal usage of MHC class II molecules to present SEB by activated T lymphocytes for superantigen-induced T cell activation and suggests that superantigen-related immune activation may depend in part on the potential of activated T lymphocytes to mediate reciprocal cell-to-cell interactions in the presence of superantigens. The decline observed in the CD8+ cell response to SEB and toxic shock syndrome toxin-1 after Day 4 was revived by exogenous recombinant interleukin-2 (rIL-2) supplementation, suggesting that the consequent autocrine or paracrine secretion of IL-2 from the responding cells is essential for subsequent cell proliferation. SEB-induced cell proliferation was significantly suppressed by anti-CD11a (lymphocyte function-associated antigen-1; LFA-1, alpha-chain) monoclonal antibody, and the inhibitory effect was most obvious in 6-day cultured CD8+ lymphocytes. The results suggest that the lymphocyte response associated with the cell-to-cell copresentation of superantigens involves LFA-1 molecules as an accessory factor, particularly in CD8+ lymphocytes.

Antibodies, Monoclonal↗

Extrafusal and intrafusal muscle effects in experimental botulinum toxin-A injection.

The effects of botulinum toxin-A was compared on both extrafusal and intrafusal muscle fibers in the biceps femoris of Wistar rats. Four days after injection no action potentials were elicited with stimulation single-fiber electromyography on the injected side. Fourteen days after injection, jitter became measurable and these values were increased on the injected side. Extrafusal muscle fibers began to atrophy on the 4th day and this continued to the 14th day postinjection. Atrophy was also evident and progressive in intrafusal muscle fibers. Increased terminal innervation ratios, end-plate spread of cholinesterase, and increased density of very small myelinated fibers in large intramuscular nerves were observed 14 days postinjection. Both extrafusal and intrafusal fibers are cholinergically innervated, and both were progressively affected by botulinum toxin, perhaps varying in degree only. In addition to partial denervation, Botulinum toxin effects in dystonia may also be related to modified spindle afferent discharge.

Adenosine Triphosphatases↗

Human T-lymphotropic virus type I-associated myelopathy and tax gene expression in CD4+ T lymphocytes.

Infection by human T-lymphotropic virus type I (HTLV-I) is associated with adult T-cell leukemia and a slowly progressive disease of the central nervous system (CNS), HTLV-I-associated myelopathy/tropical spastic paraparesis, characterized pathologically by inflammation and white matter degeneration in the spinal cord. One of the explanations for the tissue destruction is that HTLV-I infects cells in the CNS, or HTLV-I-infected CD4+ T lymphocytes enter the CNS, and this drives local expansion of virus-specific CD8+ cytotoxic T lymphocytes, which along with cytokines cause the pathological changes. Because both in the circulation and in the cerebrospinal fluid, CD8+ cytotoxic T lymphocytes are primarily reactive to the product of the HTLV-I tax gene, we sought evidence of expression of this gene within cells in the inflammatory lesions. After using double-label in situ hybridization techniques, we now report definitive localization of HTLV-I tax gene expression in CD4+ T lymphocytes in areas of inflammation and white matter destruction. These findings lend support to a hypothetical scheme of neuropathogenesis in which HTLV-I tax gene expression provokes and sustains an immunopathological process that progressively destroys myelin and axons in the spinal cord.

Adult↗

Serum of Isaacs' syndrome suppresses potassium channels in PC-12 cell lines.

Blockage of K+ channels in nerve terminals by immunoglobulin is the speculated pathomechanism of Isaacs' syndrome. Using patch-clamp technique (whole-cell clamp), we investigated the effects on K+ current of serum taken from 2 patients with Isaacs' syndrome employing the clonal cell line PC-12. The addition of a patient's serum to the perfusion solution had little effect on the K+ current of P-12 cells. In contrast, K+ current was reduced by 25-80% when cells were cultured for 3-6 days with 2% serum as compared to control serum values. Suppression of the K+ current appears to develop gradually over the period of culture. Our results suggest that the pathomechanism of Isaacs' syndrome is caused by K+ channel suppression via a humoral factor(s) in the serum, which subsequently induces nerve hyperexcitability.

Adult↗

Diversity of intrathecal antibody synthesis against HTLV-I and its relation to HTLV-I associated myelopathy.

The humoral immune response against human T-cell lymphotropic virus type I (HTLV-I) in the central nervous system (CNS) compartment and in the blood was investigated by enzyme immunoassay using 16 synthetic peptides corresponding to HTLV-I core and envelope sequences. We evaluated paired samples of cerebrospinal fluid and serum from HTLV-I seropositive Japanese patients, classified as follows: HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP; n = 39), patients with spinal cord disease ascribed to either HAM/TSP or to some concomitant, HTLV-I-unrelated disease (possible HAM/TSP; n = 6) or carriers without any clinical signs of HAM/TSP (n = 15). HTLV-I-peptide-specific intrathecal antibody synthesis was found in 79% of HAM/TSP patients, but only in 20% of carriers without HAM/TSP. The group of carriers without HAM/TSP showed local synthesis for some peptides (on average 0.3 peptides per patient). In most HAM/TSP patients, however, there was a diverse intrathecal immune response to several HTLV-I synthetic peptides (on average against 3.6 peptides per HAM/TSP patient), most frequently against gag p19 100-130, env gp21 458-488, and env gp46 175-199 and 288-317. The intrathecal antibody synthesis against several HTLV-I determinants may represent a pathogenic immune response in HAM/TSP and is possibly related to the infiltration of virus-infected T-cells in the spinal cord.

Amino Acid Sequence↗

Expression of adhesion molecules and monocyte chemoattractant protein -1 (MCP-1) in the spinal cord lesions in HTLV-I-associated myelopathy.

Leukocyte adhesion molecules to endothelium plays an important role in the pathogenesis of inflammatory diseases, including HTLV-I-associated myelopathy (HAM)/tropical spastic paraparesis (TSP). To help define the role of adhesion molecules in HAM/TSP, we studied the expression of lymphocyte function-associated antigen-1 (LFA-1), Mac-1, very late antigen-4 (VLA-4), Sialyl Lewisx (SLex), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), endothelial leukocyte adhesion molecule-1 (ELAM-1) and monocyte chemoattractant protein-1 (MCP-1) in the spinal cord lesions of HAM/TSP. The results indicate that spinal cord lesions of HAM/TSP have greater VCAM-1 expression on endothelium compared with those of controls. Infiltrating mononuclear cells, especially perivascular lesions, expressed VLA-4. Although the expression of ICAM-1 in the spinal cords was not distinctive between HAM/TSP and controls, infiltrating mononuclear cells in the spinal cords of HAM/TSP strongly expressed LFA-1 and Mac-1. ELAM-1 was expressed on endothelium in the inactive-chronic lesions from three of five HAM/HAM/TSP, but was not detectable in the spinal cords of controls. SLex reactions was detectable on occasional perivascular cells in the spinal cord of HAM/TSP, but not in those controls. MCP-1 was detectable on perivascular infiltrating cells and vascular endothelium in active-chronic lesions. This study suggest that VLA-4/VCAM-1 interaction may play an important role for lymphocyte migration into the central nervous system (CNS) and MCP-1 may also be involved in inflammatory cell recruitment to the CNS in HAM/TSP.

Aged↗

The main HTLV-I-harboring cells in the muscles of viral carriers with polymyositis are not macrophages but CD4+ lymphocytes.

We have analyzed muscle biopsy specimens from polymyositis patients who are also positive for human T cell lymphotropic virus type I (HTLV-I) using both immunohistochemistry for surface antigens of lymphocytes and macrophages and in situ polymerase chain reaction for HTLV-I proviral DNA on the same sections. We found HTLV-I in CD4+ cells but not in macrophages. This finding suggests that most of the HTLV-I-containing CD4+ cells are not macrophages but lymphocytes.

CD4-Positive T-Lymphocytes↗

Study of lower limb somatosensory evoked potentials in 96 cases of HTLV-I-associated myelopathy/tropical spastic paraparesis.

Lower limb somatosensory evoked potentials (LSEPs) were performed along with neurological evaluation in 96 HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients. The N20 latencies were abnormal in 5 cases. Central sensory conduction time (CSCT) was abnormal in 42 cases. A highly significant correlation (p < 0.001, r = 0.418) was found between CSCT and disability score. Such a correlation was not found between CSCT and other clinical findings, onset of illness, illness duration, serum and CSF antibody titer to HTLV-I and vibratory sensation. There was no difference of the mean of CSCT between the cases with sensory impairment and those without it. This shows that LSEPs are useful to estimate the disability of HAM/TSP. Also the cases with delayed CSCT and normal sensation suggest that LSEPs are capable of detecting subclinical lesions of the spinal cord in HAM/TSP.

Adult↗