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N Ohya

Publications and source records attributed to N Ohya.

At least 19 recordsLinked to original sources
PubMed1995

Origin of posterior pituitary high intensity on T1-weighted magnetic resonance imaging. Immunohistochemical, electron microscopic, and magnetic resonance studies of posterior pituitary lobe of dehydrated rabbits.

RATIONALE AND OBJECTIVES: To investigate the origin of posterior pituitary high intensity (PPHI) seen on T1-weighted magnetic resonance (MR) images. METHODS: Six rabbits, including four rabbits deprived of drinking water for 4 days and two control rabbits, were examined by MR imaging. Plasma vasopressin levels were sequentially measured by radioimmunoassay. Pituitary glands were immunostained with guinea pig anti-rabbit vasopressin antibody, and ultrathin sections of Epon/Araldite-embedded specimens were observed with a transmission electron microscope. RESULTS: In control rabbits, PPHI was noted on T1-weighted MR images, and the posterior pituitary lobe was positively immunostained with anti-vasopressin antibody. At the ultrastructural level, nerve terminals contained numerous neurosecretory granules bearing vasopressin. Conversely, plasma vasopressin levels gradually increased and PPHI was absent in 4-day dehydrated rabbits. The posterior lobe was scarcely stained with anti-vasopressin antibody, and neurosecretory granules were rarely observed. However, a number of small dispersed vesicles, possibly derived from the fragmentation of neurosecretory granule envelopes, were seen in the nerve terminal. CONCLUSIONS: Posterior pituitary high signal seen on T1-weighted MR images is attributed to neurosecretory granules bearing vasopressin.

Animals↗
PubMed1995

[A case of pulmonary thrombosis associated with primary antiphospholipid syndrome].

A 23-year-old man was admitted because of an attack of chest pain and dry cough. Chest roentogenogram showed a solitary pulmonary nodule in the left upper lobe. Chest CT showed a nodule and a small pleural effusion on the same side. Pulmonary thrombosis was diagnosed by pulmonary Ventilation/perfusion scintigraphy and pulmonary arteriography. Deep vein thrombosis was not detected except in a distal pulmonary artery. The solitary nodule disappeared spontaneously without thrombolytic therapy. An anticardiolipin antibody (IgG) test was positive. Primary antiphospholipid syndrome was diagnosed, because of the absence of physical findings suggesting other collagen vascular diseases. Patients with antiphospholipid syndrome have a high frequency of pulmonary complications that include pulmonary hypertension and pulmonary embolism. Most of the patients with pulmonary embolism have deep vein thrombosis, and pulmonary vessel thrombosis as seen in the present case is a rare complication.

Adult↗
PubMed1994

Effect of pulmonary blood flow on microvascular pressure profile determined by micropuncture in perfused cat lungs.

To clarify the role of the pulmonary microvasculature in adjusting to increased pulmonary blood flow, we measured arteriolar and venular pressure by the servo-null micropuncture method while changing the pulmonary blood flow in isolated perfused cat lungs. We divided the lung vasculature into three longitudinal segments: 1) arterial (pulmonary artery to 30- to 50-microns arteriole), 2) microvascular (between 30- to 50-microns arteriole and venule), and 3) venous (30- to 50-microns venule to left atrium). The vascular resistance was calculated by dividing the pressure gradient by the flow. The pressure gradient of the microvascular segment did not increase, whereas the pressure gradient of the arterial and venous segments increased simultaneously with flow rate. Total and microvascular resistance decreased with increase of flow rate. Resistances of the arterial and venous segments did not change with increase in flow. We conclude that the microvasculature plays a crucial role in preventing pulmonary hypertension with increases in flow by decreasing microvascular resistance.

Animals↗
PubMed1994

[A case of diffuse alveolar hemorrhage accompanied by mesangial proliferative glomerulonephritis with positive perinuclear anti-neutrophil cytoplasmic antibody].

A 62-year-old man was admitted to our hospital because of low-grade fever and hemoptysis. Chest roentgenogram revealed diffuse infiltrative shadows with air bronchograms. Bronchoalveolar lavage fluid demonstrated bloody fluid, including many hemosiderin-laden macrophages. In addition, his laboratory data on admission revealed elevation of serum creatinine and BUN, and proteinuria and hematuria on urinalysis. Renal needle biopsy showed atrophic glomeruli and mesangial proliferative glomerulonephritis without crescent formation. A history of wheezing and slight eosinophila was also present, and we therefore suspected allergic granulomatous angitis. We performed airway sensitivity and reversibility tests, which were positive, and so we judged that he had an asthmatic component. Perinuclear antineutrophil cytoplasmic antibody (P-ANCA) was positive (x 1000) with ELISA. We diagnosed diffuse alveolar hemorrhage with mesangial proliferative glomerulonephritis and bronchial asthma. His general condition improved with oral administration of corticosteroid (50 mg/day) and immunosuppressive agent (cyclophosphamide; 50 mg/day), and his major symptoms disappeared within a few days.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1994

Structure of cis-polyisoprene from Lactarius mushrooms.

Sporophores from five species of Lactarius mushrooms had a liquid rubber content of 0.1% to 7% based on the dry weight. Rubber from L. volemus, L. chrysorrheus and L. hygrophoroides was found to be a homologue of polyprenol being composed of dimethylallyl group, two trans isoprene units, 160-300 cis isoprene units, and terminal hydroxyl or ester group aligned in that order by 13C-NMR analysis. The ratio of fatty acid ester group to hydroxyl group was about 9/1 to 5/5. The number of both terminal groups and trans units decreased during aging of sporophores. Rubber from L. piperatus, L. vellereus and L. subpiperatus was found to be cis polyisoprene having very small quantities of both terminal groups and trans units. The biosynthesis of cis polyisoprene in Lactarius mushrooms was found to start from trans, trans-farnesyl pyrophosphate. The termination was assumed to occur by esterification of polyisoprenyl pyrophosphate. Occurrence of some chemical modifications on both terminal groups was presumed during aging of sporophores.

Basidiomycota↗
PubMed1994

[Bronchial arterial hemodynamics after thoracic irradiation therapy in lung cancer patients].

We evaluated bronchial arterial hemodynamics after thoracic irradiation therapy. We performed bronchial arteriography in 9 patients (8 males and 1 female) with lung cancer who received thoracic irradiation (58-72 Gy). Three patients had adenocarcinoma, 3 squamous cell carcinoma, 2 small cell carcinoma and 1 large cell carcinoma. Their clinical stages were 6 in stage IIIB and 3 in stage IV. Eight of these cases also received chemotherapy by intra-bronchial arterial infusion of anti-cancer agents (Carboplatin and/or Cisplatin). The bronchial arterial supply was patent except in the one complete remission case (small cell carcinoma of stage IIIB). In the five cases developing radiation pneumonitis, bronchial arteries demonstrated angiogenesis in the radiation fields, despite which pulmonary arteriography and/or pulmonary perfusion scintigrams showed a decreased pulmonary arterial supply. Bronchial arterial hemodynamics demonstrated no significant damage in the bronchial arteries by the thoracic irradiation therapy and/or bronchial arterial infusion of anti-cancer agents. It is suggested that patent bronchial arteries after radiation therapy promote local recurrences of lung cancer. In 5 cases, including 2 local relapsed cases and 3 cases showing no remarkable response to radical radiation therapy, we performed bronchial arterial infusion of anti-cancer agents after radiation therapy, with good responses obtained. We conclude that thoracic irradiation did not damage bronchial arteries as compared with pulmonary arteries, and that in local relapsed and radio-resistant cases bronchial arterial infusion of anti-cancer agents after radiation therapy is a useful approach.

Adult↗
PubMed1994

[Bronchiectasis].

Explore the source record for details and available documents.

Bronchiectasis↗
PubMed1994

Intraarterial infusion of autologous lymphocytes for the treatment of refractory lymphoedema. Preliminary report.

OBJECTIVE: To evaluate the results of the treatment of lymphoedema by intra-arterial infusion of autologous lymphocytes. DESIGN: Open study. SETTING: University Hospital. SUBJECTS: 13 patients with refractory lymphoedema. INTERVENTIONS: Lymphocytes were separated from the patient's own blood using a blood cell separator; about 100 cc of lymphocyte dominant blood separated from this blood was immediately infused into the proximal artery of the affected limb. Infusion was practiced once a week, and repeated 4 to 6 times. MAIN OUTCOME MEASURES: Change in size of the affected limb (defined as the difference between the affected limb and the normal limb after treatment), and softening of the edema (measured with a tension gauge). RESULTS: In all 13 patients there was softening of the affected hard limb followed by a reduction in the size of the limb (mean 64%), and the ache and sensation of heat in the limb lessened. The reduction in size was maintained in 9 of the 13 patients for three months, despite returning to their normal activities. CONCLUSION: Intra-arterial infusion of autologous lymphocytes is a promising treatment for refractory lymphoedema.

Adolescent↗
PubMed1993

[Case report and review of literature on seasonal distribution and pathogenesis of acute eosinophilic pneumonia in Japan].

A 49-year-old female was admitted because of high grade fever and dyspnea. Chest roentgenogram revealed diffuse reticulo-linear shadows. Laboratory findings showed peripheral blood eosinophilia, and blood gas analysis demonstrated severe hypoxemia. A few days after admission, her symptoms and signs improved, and the abnormal shadows on the chest roentgenograms decreased without treatment. To determine the diagnosis and evaluate the pathological findings and pathogenesis, we performed open lung biopsy. Bronchoalveolar lavage at the operation revealed increased total cell count and increased markedly, number of eosinophils, and the open lung biopsy specimen showed acute interstitial pneumonia with eosinophilic infiltration. We performed a study of precipitating antibodies against fourteen kinds of fungi and environmental provocation tests, with all results being negative. We diagnosed this case as having acute eosinophilic pneumonia clinicopathologically (Allen, 1989). We reviewed 22 cases with acute eosinophilic pneumonia previously reported in Japan including our case. These 22 cases demonstrated a seasonal tendency of onset in spring and summer. Eleven of 22 cases were tested for precipitating antibodies to several fungi, 3 of which showed positive results against Trichosporon cutaneum, Trichoderma viride and Aspergillus species. The clinical features of acute eosinophilic pneumonia resemble those of summer type hypersensitivity pneumonitis. Therefore, it is important to diagnose AEP on the basis of clinical symptoms, and precipitating antibody, viral titer and pathological findings.

Acute Disease↗
PubMed1993

[A case of radiation pneumonitis caused by treatment of lung cancer which revealed marked hypervasculality on bronchial arteriography].

A 44-year-old man was admitted to our hospital because of hemoptysis. He had been admitted to our ward in June 1991, after resection of a brain tumor at another hospital due to cerebral metastasis of lung cancer (adenocarcinoma). Systemic chemotherapy and pulmonary irradiation therapy were performed during the first hospitalization. Radiation pneumonitis occurred 1 month after the completion of radiotherapy, which responded to administration of corticosteroids. One year and 4 months later after the completion of radiotherapy, he was readmitted to our hospital because of hemoptysis. Chest computed tomogram and bronchoscopy showed no recurrence of lung cancer, so pulmonary arteriography and bronchial arteriography were performed to investigate the cause of hemoptysis. Pulmonary arteriograms showed diminished vascularity in the area of radiation fibrosis, but a bronchial arteriogram showed inflammatory hypervascularization in the same field. We considered that the bronchial arterial angiogenesis induced by radiation pneumonitis was the cause of hemoptysis. Bronchial arteriography is necessary in cases of radiation pulmonary fibrosis with hemoptysis without obvious recurrence of tumor. If the growth of new blood vessels in the bronchial artery can be induced by radiation therapy, the administration of anti-cancer agents to the bronchial artery should be considered in the treatment of recurrent lung cancer after radiation therapy.

Adenocarcinoma↗
PubMed1993

[A case of interstitial pneumonia of polymyositis-dermatomyositis with various pathological findings in open lung biopsy].

A 60-year-old woman was admitted to our hospital with a two month history of dry cough and dyspnea on exertion. A chest roentgenogram revealed diffuse interstitial shadows with a reduction of lower lung volume. Laboratory examinations revealed an increase in CPK and aldolase. There was decreased proximal muscle power, and the findings of a biopsy of the right deltoid were compatible with polymyositis. Myositic symptoms were stable, but the respiratory symptoms worsened, and an open lung biopsy was performed for diagnosis and to determine the best treatment. The histological findings of biopsy materials demonstrated active interstitial pneumonia complicated by cellular interstitial pneumonia, bronchiolitis obliterans organizing pneumonia, usual interstitial pneumonia and lymphoid hyperplasia. The patient responded well to adrenocorticosteroid and immunosuppressive therapy, and is now attending as an out patient. It is well known that PM-DM can be associated with interstitial pneumonia, and this complication is an important prognostic factor clinically. The pathological patterns of interstitial pneumonia in PM-DM may be divided into usual interstitial pneumonia and bronchiolitis obliterans organizing pneumonia. Furthermore, it is well documented that these patterns are concurrent with the response to adrenocorticosteroid and prognostic factors. However, our case of PM-DM, in which various patterns such as rheumatoid arthritis (RA) were pathologically revealed, cannot be considered as having uniform pathological pattern. We consider that pulmonary pathological patterns of PM-DM are very varied, as with RA. It is a very important to evaluate the nature of these patterns and the subsequent clinical course in PM-DM with interstitial pneumonia.

Biopsy↗
PubMed1993

[A new technique for evaluating the respiratory tract--digital subtraction bronchography (DSBG)].

Bronchography is essential for evaluation of morphological changes in the bronchial tree. However, conventional bronchography using Propyliodone (Dionosil) is extremely invasive, especially to those with pulmonary infections. In the present study, we developed a new less invasive method of bronchography with the aid of digital subtraction technique (DSBG), and evaluated its clinical benefits. Bronchography was performed by injecting contrast medium (Iopamidol: Iopamiron 300) via the lumen of the bronchoscope (Olympus Type 20), and image processing of the respiratory tract was performed using digital subtraction technique. From 1991 to 1992, DSBG was performed in 15 cases (8 bronchiectasis, 1 diffuse panbronchiolitis, 1 lung cancer, 1 pulmonary emphysema, and 4 others). DSBG clearly demonstrated the morphological changes of large and segmental bronchial lesions in cases of bronchiectasis and lung cancer, as well as conventional bronchography using Dionosil. In addition, it was possible to image the morphological changes of bronchiolar lesions in diffuse panbronchiolitis and pulmonary emphysema to the same detail as obtained using classical selective alveolo-bronchography (SAB). Since DSBG can provide enhanced images the bronchial tree without being affected by cardiac and respiratory movements, we could obtain detailed information on bronchial and/or bronchiolar lesions. With respect to side effects, Iopamiron was quickly drained and/or absorbed within 2 hours after injection. Pulmonary infection and bronchial bleeding, which are well known primary complications of classical bronchography using Dionosil, were not observed. We conclude that 1) DSBG is useful new technique for examining morphological changes of the respiratory tract, and 2) DSBG is less invasive than conventional bronchography.

Adult↗
PubMed1993

[Detection and identification of tuberculosis by amplification of mycobacterial DNA from clinical cultured samples].

We examined 57 cultured mycobacteria using a method based on polymerase chain reaction (PCR), slot blot hybridization and dideoxy sequencing of nucleotides for detection of M. tuberculosis. Using standard microbiological tests, 34 of 57 specimens were identified as M. tuberculosis and the rest as atypical mycobacteria. Two of 34 specimens that contained M. tuberculosis were not hybridized with a probe specific for M. tuberculosis. These two specimens were identified as atypical mycobacterium by nucleotide sequencing. An atypical mycobacterium specimen that was hybridized with a prove specific for M. tuberculosis was identified as M. tuberculosis using nucleotide sequencing. These results suggest that the approach using PCR and slot blot hybridization for detection of mycobacterium may be more accurate than standard microbiological tests in the rapid and definitive diagnosis of mycobacterial infection.

DNA Probes↗
PubMed1993

[A case of hypersensitivity pneumonitis in Pholiota nameko's manufacturer].

A 58-year-old female was admitted to our hospital because of fever and dyspnea on exertion. She has been working in the factory making Pholiota nameko for 8 years. Her chest X-ray revealed diffuse linear and fine nodular shadows in both lower lung fields. Hypoxemia was seen on blood gas analysis. Bronchoalveolar lavage (BAL) and transbronchial lung biopsy (TBLB) were performed. Differential cell count of the BAL fluid showed lymphocytosis and CD4/8 was decreased. TBLB specimens revealed bronchioloalveolitis. Precipitins against Trichosporon cutaneum were detected by Ouchterlony method. These findings are compatible with hypersensitivity pneumonitis, and Trichosporon cutaneum may have been causative antigen in this case. Trichosporon cutaneum is often detected in the Japanese summer-type hypersensitivity pneumonitis. This case suggests that Trichosporon cutaneum is one cause of hypersensitivity pneumonitis in workers at factories making Pholiota nameko.

Alveolitis, Extrinsic Allergic↗