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Biomedical subjects

M Oda

Publications and source records attributed to M Oda.

At least 19 recordsLinked to original sources
PubMed1992

Glial fibrillary tangles with straight tubules in the brains of patients with progressive supranuclear palsy.

A recent report has described the appearance of silver positive, tau-immunoreactive astrocytes in the brains of patients with progressive supranuclear palsy (PSP) (Neurosci. Lett., 135 (1992) 99-102). In this study we confirmed this finding in two cases of PSP by using Bodian silver staining and immunohistochemistry with antibody to human tau protein. By electron microscopy we demonstrated that fibrillary masses present in these unique astrocytes were made up of straight tubules that were indistinguishable from those of neurofibrillary tangles of PSP. The term 'glial fibrillary tangle' was proposed for these structures.

Aged↗
PubMed1992

Blockade by trifluoperazine of a Ca(2+)-activated K+ channel in rat hippocampal pyramidal neurons.

The effects of trifluoperazine, a phenothiazine derivative, on the large-conductance Ca(2+)-activated K+ channel (BKCa) in dissociated rat hippocampal pyramidal neurons were examined using the inside-out configuration of the patch-clamp technique. The BKCa was activated by 12.6 microM Ca2+ on the internal surface of the membrane patch. The single channel conductance of the BKCa was 244 +/- 17.5 pS (n = 10) in symmetrical solutions of 150 mM K+. Trifluoperazine, applied on the internal surface of the membrane, decreased the open probability of the channel without changing the single channel conductance. The reduction in the open probability was well described by a block of the open state of the channel in a simple sequential model. The apparent dissociation constant (KD) for the reduction was calculated to be 1.4 microM and the Hill coefficient 0.69 at +20 mV. The inhibition was voltage dependent, being more pronounced at depolarized voltages. The voltage dependence enabled us to estimate that the binding site for the agent in the channel lies about half way across the membrane electrical field. It is concluded that trifluoperazine blocks the open state of the BKCa, which is known to provide an outward current for repolarization and afterhyperpolarization of the neuronal action potential. This may result in a decrease in spike intervals during burst firing of neurons.

Action Potentials↗
PubMed1992

Maintenance by androgen and thyroid hormone of androgen-induced convoluted tubular cells in mouse submandibular glands.

Injection of 5 alpha-dihydrotestosterone (DHT) into castrated adult female mice stimulated the proliferation of a small proportion of the convoluted tubular cells in the submandibular glands. We investigated the effects of DHT and thyroxine (T4) on the maintenance of these proliferated convoluted tubular cells. For this, castrated adult female mice that had been treated daily with DHT for 3 days and then once with [3H]thymidine, received a first series of daily injections of DHT for various periods or T4 for 10 days, and then a second series of injections of treatment with DHT or T4, or no further treatment. The second series of treatments with DHT or T4 maintained the percentages of 3H-labeled convoluted tubular cells at similar or slightly lower levels than those at the end of the first series of treatments. In mice that did not receive the second series of treatments, the percentages of 3H-labeled convoluted tubular cells decreased markedly, becoming significantly lower than those at the end of the second series of treatment with DHT or T4. We also examined the effect of DHT on the proliferation of convoluted tubular cells of castrated adult female mice that had received 10 daily injections of DHT and then no treatment for 28 days. In these mice, the cells did not proliferate markedly on stimulation with DHT. These results suggest that androgen and thyroid hormone maintain convoluted tubular cells that have proliferated in response to androgen, and that the convoluted tubular cells may become unresponsive to androgen in terms of proliferation after their exposure to androgen.

Animals↗
PubMed1992

Immunocytochemical and ultrastructural studies of neuronal and oligodendroglial cytoplasmic inclusions in multiple system atrophy. 2. Oligodendroglial cytoplasmic inclusions.

Oligodendroglial cytoplasmic inclusions (OCI) in multiple system atrophy were investigated immunocytochemically and ultrastructurally. Among the 17 cases examined, 16 had OCIs. Almost all OCIs were positive for both alpha B-crystallin and ubiquitin. The antibodies against tubulin, paired helical filament and tau stained OCIs to various extents. Ultrastructurally OCIs consisted of meshworks of granule-associated filaments about 25 nm in diameter that sometimes formed flame-shaped tangle-like structures. Immunoelectron microscopy showed that an epitope of alpha B-crystallin was located on the granule-associated filaments composing OCIs. Our studies further support a cooperative role of alpha B-crystallin, ubiquitin and cytoskeletal protein in the formation of some types of intracytoplasmic inclusions.

Adolescent↗
PubMed1992

Peculiar axonal debris with subsequent astrocytic response (foamy spheroid body). A topographic, light microscopic, immunohistochemical and electron microscopic study.

Foamy spheroid bodies (FSBs) are described, as newly identified pathological structures occurring in human brain. FSBs favoured the substantia nigra pars reticulata (SNPR) and/or globus pallidus (GP) in degenerative conditions especially postencephalitic parkinsonism, progressive supranuclear palsy, pallido-nigro-luysial atrophy and multiple system atrophy. No FSBs were observed anywhere in the presence of substantia nigra pars compacta (SNPC) degeneration, such as occurs in idiopathic Parkinson's disease, or luysio-pallidal system degeneration, such as found in dentato-rubro-pallido-luysial atrophy or Joseph's disease. FSBs were also occasionally identified in the substantia nigra (SN) and/or GP of aged persons. In addition to SN and GP lesions, FSBs were seen in diffuse axonal lesions of long fibre tracts (the corpus callosum, the superior cerebellar peduncle) after non-missile head injuries, and in peri-infarct lesions. Under the light microscope, FSBs appear as slightly eosinophilic, foamy and nearly round objects with vague outlines, measuring approximately 10-50 microns in diameter. Some FSBs contain coarse, eosinophilic clusters at their periphery. FSB stained black when stained by the Gallyas silver method. Some FSBs were immunohistochemically positive for synaptophysin and 68 kDa neurofilament. Glial fibrillary acidic protein-positive fibres were observed alongside and/or inside some FSBs. Electron microscopically, FSBs were found to consist of collections of neuritic debris containing a variety of dense bodies and a small number of both mitochondria and neurofilaments. Some such collections were surrounded by astrocytic processes. These findings strongly suggest that FSBs are collections of small axonal debris destined for removal by astrocytes in due course. A variety of factors (degeneration of the SNPR and/or the GP, injury, infarction, ageing) seemed to be responsible for the histogenesis of FSBs.

Adult↗
PubMed1992

Immunohistochemical expression of microtubule-associated protein 5 (MAP5) in glial cells in multiple system atrophy.

An immunohistochemical study focusing on glial cells was performed using monoclonal antibodies against microtubule-associated proteins (MAP1, MAP2 and MAP5), transferrin, leukocyte common antigen (LCA) and glial fibrillary acidic protein (GFAP) in 5 cases of multiple system atrophy (MSA) exhibiting olivopontocerebellar atrophy and striatonigral degeneration. An antibody to MAP5, a fetal antigen in developing brain, was strongly demonstrated in the glial cytoplasmic inclusions (GCIs) which have recently drawn a great deal of attention and were observed in all 5 cases of MSA. Moreover, MAP5-positive glial cells (MAP5-Gs) were present in significantly higher number than in the controls in various regions where GCIs were found, predominantly in putamen, substantia nigra, cerebellar white matter and internal capsule. LCA and transferrin, markers of microglia and oligodendroglia, respectively, were immunohistochemically detected in some MAP5-Gs. GFAP, on the other hand, was not expressed in MAP5-Gs at all. These findings suggest that MAP5-Gs consist of reactive microglia and oligodendroglia. Our study is the first to demonstrate immunohistochemical detection of MAP5 in glial pathological changes in MSA.

Aged↗
PubMed1992

Increased monoamine turnover in the subfornical organ area following body fluid depletion.

To clarify whether monoaminergic inputs to the subfornical organ (SFO) area participate in fluid regulatory systems, we examined the effects of body fluid depletion on monoamine turnover in the region of the SFO using microdialysis techniques in rats. An iso-osmotic reduction of fluid volume following subcutaneous treatment with polyethylene glycol (PEG) significantly increased dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), and 5-hydroxyindoleacetic acid (5-HIAA) concentrations in the SFO area. 5-hydroxytryptamine (5-HT) in the SFO area could be detected after the PEG treatment, while 5-HT was undetectable before the treatment. The data imply that both dopaminergic and serotonergic systems in the SFO area may be involved in controlling body fluid balance.

Animals↗
PubMed1992

Analysis of the transcriptional activity of the hut promoter in Bacillus subtilis and identification of a cis-acting regulatory region associated with catabolite repression downstream from the site of transcription.

Levels of transcripts initiated at a hut promoter in Bacillus subtilis were analysed. The addition of histidine to the culture medium increased the level of the transcript sixfold. In the presence of histidine and glucose together, the level of the transcript was reduced to the level in the absence of induction. Furthermore, addition of a mixture of 16 amino acids to cultures of induced cells and of catabolite-repressed cells decreased levels of the transcript 16-fold and 2.6-fold, respectively. Thus, it appears that at least three regulatory mechanisms associated with induction, catabolite repression, and amino acid repression, control the transcriptional activity of the hut promoter. Expression of the hut promoter-lacZ fusions that contained various regions of the hutP gene and deletion analysis of the hutP region revealed a cis-acting sequence associated with catabolite repression that was located between positions +204 and +231 or around position +203.

Amino Acids↗
PubMed1992

Blockade by local anaesthetics of the single Ca(2+)-activated K+ channel in rat hippocampal neurones.

1. Effects of local anaesthetics on single Ca(2+)-activated K+ channels were investigated using the inside-out configuration of the patch-clamp technique in single pyramidal neurones, which were freshly dissociated from rat hippocampus by use of proteolytic enzymes. 2. No significant effect was observed when 2 mM benzocaine was applied on either side of the membrane patch, or when 2 mM lignocaine or QX-314 was applied to the external surface of the membrane. 3. Lignocaine 1 mM, applied to the internal surface, slightly reduced the amplitude of the single K+ channel current. When applied to the internal surface QX-314 reduced the amplitude of the K+ channel current, accompanied by an increase in noise in the open channel current, suggesting a fast flickering block. The blocking effect of QX-314 on the outward current increased with depolarization, suggesting a binding site for the drug at an electrical distance of about 0.5 across the membrane field. 4. The open time histogram showed one exponential component and the closed time histogram showed at least two components. The mean open time of the outward current was increased when the amplitude was reduced by the drugs. 5. The ionized form of the local anaesthetics had a similar action on the Ca(2+)-activated K+ channels to that on Na+ channels, that is, they enter into the channel from the cytoplasmic side to induce open channel block. The blocking kinetics, however, might be so fast that they were beyond the frequency response of our recording apparatus, thus the recorded current amplitude was decreased. In contrast the K+ channel was not accessible via hydrophobic pathways for the neutral form, which is also known to block the sodium channel.

Anesthetics, Local↗
PubMed1992

Recombinant human granulocyte-colony-stimulating factor in the treatment of patients with chronic benign granulocytopenia and congenital agranulocytosis (Kostmann's syndrome).

Seven patients with chronic benign granulocytopenia and nine patients with congenital agranulocytosis, received consecutive seven-day courses of recombinant human granulocyte-colony stimulating factor at a starting dose of 50 micrograms/m2/day, subcutaneously. If there was no response the doses were increased to 300 micrograms/m2. All patients with chronic benign granulocytopenia responded rapidly at the minimum dose within 1-3 days after administration. By contrast, only three of the nine patients with congenital agranulocytosis responded within 1-7 days at this dose. Four patients with congenital agranulocytosis showed a response between days 7-19 at a dose of granulocyte-colony-stimulating factor 100-200 micrograms/m2 but in the remaining two cases no response was obtained. The administration of granulocyte-colony-stimulating factor was shown to be safe and effective also in reducing infectious episodes in these patients. Previously it was reported that granulocyte-colony-stimulating factor 10-30 micrograms/kg/day was effective for patients with congenital agranulocytosis. These results indicate that patients with congenital agranulocytosis may require much higher doses of recombinant human granulocyte-colony-stimulating factor than patients with chronic benign granulocytopenia and that the response to ordinary doses of recombinant human granulocyte-colony-stimulating factor may be useful in differentiating between chronic benign granulocytopenia and congenital agranulocytosis.

Adolescent↗
PubMed1992

Creutzfeldt-Jakob disease with congophilic kuru plaques: CT and pathological findings of the cerebral white matter.

In a patient whose Creutzfeldt-Jakob disease with congophilic kuru plaques that was proved at necropsy, the early brain CT showed low-density areas in the cerebral white matter before cortical atrophy and ventricular enlargement became apparent. Subsequently, there occurred diffuse white matter lucency and severe brain atrophy. At necropsy, there was severe white matter destruction which was more prominent than cortical neuronal loss. Serial CT scans were of great value for demonstrating the early and predominant changes in the cerebral white matter.

Animals↗
PubMed1992

[Antigenicity study of 6-amidino-2-naphthyl 4(-)[(4,5-dihydro-1H-imidazol-2-yl)amino] benzoate dimethanesulfonate (FUT-187) in guinea pigs and mice.

Antigenicity study of 6-amidino-2-naphthyl 4(-)[(4,5-dihydro-1H-imidazol-2-yl)amino] benzoate dimethanesulfonate (FUT-187), a new protease inhibitor, was investigated in guinea pigs and mice and the following results were obtained. 1. In guinea pigs immunized with FUT-187 plus adjuvant by intramuscular/subcutaneous routes, ASA, ACA and PCA reactions challenged intravenously or intradermally were positive. 2. In guinea pigs immunized with FUT-187 plus adjuvant by intramuscular/subcutaneous routes, ASA and PCA reactions challenged orally were negative. 3. In guinea pigs immunized with FUT-187 by the oral route, ASA, ACA and PCA reactions were negative. 4. In guinea pigs immunized with IABA and AN plus adjuvant by intramuscular/subcutaneous routes, ASA and PCA reactions were negative. 5. 48-hr PCA reactions were elicited with sera obtained from BALB/c and C3H/He mice immunized with FUT-187 plus adjuvant by the intraperitoneal route, responses were negative. 6. From the results of hapten inhibition tests using anti-FUT-187 guinea pig serum, it is suggested that the antigenicity of FUT-187 is attributable to the its benzoic acid.

Adjuvants, Immunologic↗
PubMed1992

Primary extramedullary plasmacytoma of the lung.

A case with primary plasmacytoma of the lung is described. The patient, a 55-year-old Japanese female, who simultaneously had a pulmonary plasmacytoma and bladder carcinoma. The bladder tumor was treated with transurethral resection. Pathologically, the bladder tumor was a non-invasive, papillary transitional cell carcinoma, grade II. The lung tumor was located in the right upper lobe and upper lobectomy was performed. The tumor measured 2.8 x 2.7 x 2.0 cm and had a white-yellowish cut surface. Histologic, electron microscopic and immunohistochemical examinations of the lung tumor revealed monoclonal proliferation of plasma cells (IgA, lambda light chain). There was no evidence of multiple myeloma.

Female↗
PubMed1992

Seven patients with plasma cell granuloma (inflammatory pseudotumor) of the lung, including two with intrabronchial growth: an immunohistochemical and electron microscopic study.

Seven patients (mean age, 50.7 +/- 20.4 years; range 21-77) with plasma cell granuloma (PCG) of the lung are reported. Cough and sputum were the most common presenting symptoms, followed by fever. Elevated erythrocyte sedimentation rate and serum C-reactive protein levels were found in all patients tested. Radiologically, five cases presented as solitary, well-circumscribed masses and two as ill-defined, pneumonia-like densities. One showed focal calcification. No predilection of occurrence was observed in either lobe of the lung. Histologically, the lesions consisted of a proliferation of mature plasma cells and reticulo-endothelial cells supported by a stroma of granulation tissue, with varying degrees of myxoid change or collagenization. Angioinvasion within the lesion was observed in 4 of the 7 cases. Immunohistochemical staining revealed the IgG-predominant polyclonal nature of the plasma cells, indicating a reactive inflammatory process rather than a neoplastic one. Electron microscopy confirmed the benign nature of the plasma cells with fibroblast and myofibroblast proliferation admixed with that of other inflammatory cells.

Adult↗
PubMed1992

Second surgical intervention for recurrent and second primary bronchogenic carcinomas.

Second operations were performed in 1961-1990 on 23 patients with non-small cell bronchogenic carcinoma, constituting 2.5% of 906 who had undergone pulmonary resection for such tumor and 3.6% of the 641 with apparently curative surgery. The second operation was performed for recurrent tumor in 15 cases and for second primary tumor in eight. Five-year survival after the first operation was 30% in the former group and 88% in the latter (significant difference). Among the total 23 patients, this survival rate was 51%. The study indicates that an aggressive attitude to second surgical intervention is warranted. For early detection of second lesions, follow-up at maximally 6-month intervals should be continued for more than 5 years after the first operation.

Adenocarcinoma↗
PubMed1992

[Two cases of familial pulmonary arteriovenous fistula].

Two cases of familial pulmonary arteriovenous fistula are reported. Case 1: A 54-year-old woman was admitted with exertional dyspnea. An abnormal shadow on chest X-ray had been noted since the age of 37 years. Pulmonary angiography demonstrated bilateral pulmonary arteriovenous fistulas. Case 2: A 25-year-old man, the son of Case 1, was admitted for operation for the same disease. The mother and son both suffered from repeated epistaxis due to Rendu-Osler-Weber disease. In order to reserve pulmonary function, fistulectomy was performed in both cases, and their subsequent clinical courses were good.

Adult↗