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M Onizuka

Publications and source records attributed to M Onizuka.

At least 55 records · Page 3Linked to original sources
PubMed1995

Cytochrome P-450 transfer from adrenocortical submitochondrial particles to liposome membranes.

The transfer of cytochrome P-450 from bovine adrenocortical submitochondrial particles (smp) to unilamellar liposome membranes was investigated using a table top ultracentrifuge. Submitochondrial particles were incubated with liposome membranes at 25 degrees C and precipitated by ultracentrifugation at 200000g for a few minutes at 25 degrees C. All liposome vesicles were recovered in the supernatant. Almost no proteins were detected in the supernatant when only smp were incubated and centrifuged. SDS-PAGE revealed one main protein band for the supernatant when smp were incubated with liposome vesicles at 25 degrees C. This band was reactive to anti-P-450scc IgG. Inaccuracy in time for kinetic studies of the transfer was less than 0.5 min. Transfer of P-450scc from smp to liposome membranes was further demonstrated by the decrease in side-chain cleavage activity of smp for endogenous cholesterol after incubation. Cytochromes P-450 accounted for about 70% of the transferred proteins in the liposome membranes, the amount of which increased exponentially with the incubation time. The inverse value of the relaxation time of the transfer increased linearly with the smp concentration and decreased hyperbolically with the liposome concentration. These results coincide with a mechanism by which cytochrome P-450 dissociates from smp membranes, diffuses, and binds to the liposome membranes. In the transfer of cytochrome P-450, the dissociation from smp membranes was deduced to be the rate-limiting step.

Adrenal Cortex↗
PubMed1995

[Transpericardial completion pneumonectomy with omental pedicle flap for chronic empyema caused by bronchiectasis].

A 61-year-old man received right middle and lower lobectomies for lung abscess caused by bronchiectasis in 1957. Since the right upper lobe was destroyed and multiple peripheral bronchopleural fistulae developed later, open thoracostomy was done in 1990. For this patient we performed transpericardial completion pneumonectomy with omental pedicle flap in 1993. He was complicated in a transient thoracic empyema. But he recovered by open drainage followed by surgical closure using Clagett's method and remains well 2 years after the radical operation. Transpericardial approach with omental pedicle flap though a median sternotomy seemed useful to prevent the postpneumonectomy bronchopleural fistula in this patient with thoracic empyema. But the primary closure of the empyema cavity should not be done, if dead space remains in the pleural cavity.

Bronchiectasis↗
PubMed1995

[Criteria of limited operation for bronchial carcinoid].

The purpose of this study is to establish criteria of limited operation for bronchial carcinoid. Ten cases surgically treated in our hospital and 47 cases reported in Japan from 1981 to 1992 were examined. Thirty-nine cases had typical carcinoid tumor and 18 had atypical. Limited operation, such as pulmonary segmentectomy, wedge resection or partial resection, was performed in 12 cases. In these, all patients of typical type were alive except for a case died of other disease. However, two patients of atypical type died of distant metastasis of the tumor. No lymph node metastasis was revealed in all cases of typical type. On the contrary, in cases of atypical type, six had n1 and two had n2 disease. Moreover, two cases with n1 disease had pulmonary metastasis. Therefore, patients with typical bronchial carcinoid can be cured by limited operation, but radical operation should be indicated for atypical bronchial carcinoid.

Adult↗
PubMed1994

Endoscopic criteria of early squamous cell carcinoma of the bronchus.

BACKGROUND: Early lung cancer, not extending beyond the bronchial cartilaginous layer without regional lymph node involvement is considered curable by endoscopic laser therapy or limited surgery. The endoscopic criteria for early squamous cell carcinoma of the bronchus, however, have not yet been determined. METHODS: For 44 resected lesions of roentgenographically occult bronchogenic squamous cell carcinomas, the relationship between endoscopic findings and the degree of histologic extent of tumor was examined. RESULTS: The lesions were divided into three types: polypoid or nodular (PN), flatly spreading (FS), and mixed. Thirty-three lesions arising from the central bronchus included 7, 19, and 7 of the PN, FS, and mixed types, respectively. In the central lesions, the degree of transmural invasion and the greatest dimension correlated, but the degree of intramural invasion of PN-type lesions was higher than that of the FS type. The PN-type lesions smaller than 10 mm and the FS type smaller than 15 mm in greatest dimension were found within the cartilaginous layer without regional lymph node involvement. All lesions of the mixed type were larger than 20 mm. Three of the lesions larger than 20 mm had regional lymph node involvement. All 11 lesions originating in the peripheral bronchus were of the FS type, and a lesion of only 5 mm in greatest dimension had extracartilaginous invasion. CONCLUSIONS: The endoscopic criteria of early squamous cell carcinoma of the bronchus may be applied to central PN lesions smaller than 10 mm and central FS lesions less than 15 mm in greatest dimension. Any lesions of mixed type should be excluded from the criteria.

Aged↗
PubMed1994

Pleural dissemination in non-small cell lung cancer: results of radiological evaluation and surgical treatment.

The aims of this study are to evaluate the diagnostic ability of chest computed tomography (CT) in the early detection of pleural disease and to analyze the results of surgical treatment for lung cancer with pleural dissemination. Twenty-three non-small cell lung cancer patients with pleural dissemination, but without distant metastasis, underwent pleuropulmonary resection during the past 15 years. Chest CT scans were obtained preoperatively in 21 of those patients. In eight patients without pleural effusion, small pleural nodules, about 3-5 mm in size, were found in their chest CT. However, during surgery, small nodules were more frequently observed on the parietal pleura than on the visceral pleura in five of them. Therefore, early detection of the dissemination by chest CT seemed limited to only those of the visceral pleura. In the survival curve after resection, there was no difference among the patients with n2 disease, but there was a significant difference between the patients without n2 disease and those with it (P < 0.05). The presence of n2 disease appeared to be a poor prognostic sign in this form of advanced lung cancer.

Adult↗
PubMed1994

Endothelin receptor subtypes in human versus rabbit pulmonary arteries.

We studied which endothelin (ET) receptor subtypes mediate ET-1-induced vasocontraction in the human pulmonary artery (PA) compared with the rabbit PA. ET-1 produced potent contraction in both human and rabbit isolated PAs. In human PA, ET-1-induced contraction was competitively antagonized by BQ-123 (an ETA receptor antagonist) with a pA2 value of 7.68. In rabbit PA, however, even a high concentration of BQ-123 (1 microM) did not affect the contraction. BQ-3020 (an ETB receptor agonist) produced potent contraction in rabbit PA but not in human PA. Binding assays of the membrane preparations showed that human and rabbit PAs contained ETA and ETB receptors in ratios of 93:7 and 23:77, respectively. These results suggest interspecies differences in the ET receptor subtypes that mediate ET-1-induced vasocontraction; ETA receptors are dominant in the human PA, whereas ETB receptors are dominant in the rabbit PA. Furthermore, the predominance of ETA receptors in human PA was supported by autoradiographical studies. If ET-1 acts as a physiological and/or pathophysiological vasocontractor in the human pulmonary circulation, an ETA receptor antagonist would function as a pulmonary vasodilator in humans.

Aged↗
PubMed1994

[New endoscopic laser treatment for unilateral vocal cord paralysis after pulmonary resection].

In two patients who had developed aspiration due to left recurrent laryngeal nerve injury during radical resection for lung cancer, low power Nd:YAG laser irradiation of the paralyzed vocal cord was performed through a bronchofiberscope. With irradiation, the paralyzed vocal cords of both patients swelled and became fixed at the median portion of the glottis. Thereafter, aspiration disappeared. Thus, this new application of Nd:YAG laser irradiation is apparently quite useful in treating aspiration due to unilateral vocal cord paralysis immediately after pulmonary resection.

Bronchoscopy↗
PubMed1993

Successful reconstruction for combined tracheal and bronchial disruption.

After a head-on automobile collision, a 21-year-old man was admitted with respiratory distress and subcutaneous emphysema. Bronchoscopy revealed a disruption of the trachea and a complete transection of the intermediate bronchus. A right posterolateral thoracotomy was performed, and both lesions were reconstructed primarily using absorbable materials.

Accidents, Traffic↗
PubMed1992

Effects of endothelin-1 and conversion of big endothelin-1 in the isolated perfused rabbit lung.

We examined the effects of endothelin-1 (ET-1) on pulmonary hemodynamic and transvascular fluid filtration and the conversion of big endothelin-1 (big ET-1), a precursor of ET-1, in isolated perfused rabbit lungs at constant vascular and airway pressures. Furthermore we examined whether ET-1 contributes to cyclooxygenase metabolism. The perfusate flow decreased significantly after bolus administration of 1 or 0.1 nmol of ET-1. Lung weight did not increase throughout the experimental period. Big ET-1- (1 nmol) induced decrease in the flow was slow in developing, although the maximum response was comparable to that induced by the same dose of ET-1. The concentration of bit ET-1 in the perfusate progressively decreased, while that of ET-1 increased in a time-dependent manner. Phosphoramidon, an inhibitor of metalloproteinase, suppressed the pressor effect of big ET-1 (P less than 0.01) and the increase in the concentration of ET-1 in the perfusate (P less than 0.05). The present findings provide the first evidence suggesting that the potent vasocontractile effect of big ET-1 in pulmonary circulation can be attributed to the production of ET-1 by the conversion from big ET-1 in the vascular bed. ET-1-induced perfusate flow changes were not affected by indomethacin, and the concentration of 6-ketoprostaglandin F1 alpha, a metabolite of prostacyclin, did not increase after ET-1 administration.

Animals↗
PubMed1992

[Imprint cytodiagnosis of lymph node metastasis in resected lung cancer].

The cytological examination of lymph node imprints is a rapid and useful method for diagnosis of lymph node metastasis. We applied this technique for the diagnosis of regional lymph node metastasis of resected lung cancer, and compared its diagnostic value with histological examination. The accuracy rate of imprint cytology is 97.3%, and the sensitivity rate is 100%. We conclude that imprint cytology of lymph node for diagnosis of cancer metastasis is highly accurate and simple, and its diagnostic value may be equal to that of routine histological examination.

Adenocarcinoma↗
PubMed1992

[Gianturco expandable metallic stents in the treatment of superior vena cava syndrome caused by lung cancer].

Treatment of superior vena cava syndrome (SVCS) caused by advanced lung cancer is still controversial. We inserted Gianturco expandable metallic stents (GEMS) in 5 patients with SVCS due to the extension of lung cancer. GEMSs were introduced intravenously through the catheter after intraluminal balloon dilation of the stenotic sites. SVCS was successfully and easily relieved by this method without any significant complication. GEMS placement seems to be a useful alternative to bypass grafting procedure for the treatment of SVCS.

Adult↗
PubMed1992

Endothelin-1 mediates regional blood flow during and after pulmonary operations.

To investigate the role of endothelin-1, a potent vasoconstrictor peptide produced by vascular endothelial cells, in the physiologic response to surgical stress, we measured plasma endothelin-1 concentrations by a sandwich-enzyme immunoassay in patients with lung cancer undergoing pulmonary operations (n = 12). In the first group (n = 6), we measured plasma endothelin-1 concentrations at multiple sampling sites (median cubital vein, pulmonary artery, and left atrium). Plasma endothelin-1 levels were significantly increased at all sampling sites at the end of the operation. Although there was no difference between the increased plasma levels of endothelin-1 in the pulmonary artery and in the left atrium, the increased level in the median cubital vein (peripheral venous blood) was significantly higher than that in the pulmonary artery (mixed venous blood). This result suggests that the production of endothelin-1 might differ between various organs under surgical stress. In the second group (n = 6), we measured plasma endothelin-1 concentrations both in the median cubital vein and in the ipsilateral radial artery, and also measured cardiac output and forearm blood flow. The increase in endothelin-1 levels in the median cubital vein was significantly higher than that in the radial artery after the operation. The endothelin-1 output from the forearm, calculated by the forearm blood flow and the arteriovenous difference of endothelin-1 concentrations, significantly increased after the operation. Although the cardiac output significantly increased after the operation, the forearm blood flow significantly decreased. The present findings provide a novel hypothesis that the preferential release of endothelin-1 from the peripheral vasculature of the forearm may partly contribute to a compensatory response to surgical stress, for example, the reduction of local blood flow in nonvital organs so as to increase the blood flow in vital organs.

Adult↗
PubMed1992

[Evaluation of postoperative pulmonary complications and remaining pulmonary arterial flow of lobectomized lung cancer patients using pulmonary digital subtraction angiography].

Postoperative pulmonary complications cause the decrease of the flow of remaining pulmonary circulation. We examined the effects of the difference of resected lobes on the postoperative course and remaining pulmonary circulation of the lobectomized lung cancer patients using a pulmonary digital subtraction angiography. In all cases with preoperative pulmonary complications, circulatory flow of the remaining lung on the operated side significantly decreased. In the cases without preoperative pulmonary complications, only the cases performed left upper lobectomy developed the decrease of the circulatory flow on the operated side. This seemed to be chiefly caused by a postoperative continual atelectasis of the remaining lower lobe due to kinking of the bronchus. On the other hand, the postoperative decrease of the residual pulmonary circulatory flow on the operated side was not developed in the cases undergoing a segmentectomy, even with pulmonary complications. Therefore, for any case requiring a left upper lobectomy or the case with an impaired lung requiring any type of lobectomy, contralateral pulmonary function should be exactly evaluated preoperatively.

Aged↗
PubMed1992

[A successful surgical treatment of chronic traumatic mid-descending thoracic aortic aneurysm].

A 48-year-old woman with chronic mid-descending thoracic aortic aneurysm was successfully repaired. She received a blunt chest trauma due to automobile accident at July in 1988. Left upper lobectomy was performed for her lung contusion. March 1990, she admitted our hospital with abnormal shadow revealed by a chest roentgenogram. A computed tomogram of the chest and an aortogram revealed two false aneurysms. One of them was located at mid-descending thoracic aorta and another was aortic isthmus. Under a partial femoral veno-arterial bypass, a Dacron graft replacement of mid-descending thoracic aorta was performed and aneurysm of isthmus was wrapped by Teflon mesh after the left pneumonectomy. 2 months after the operation, bronchopulmonary fistula occurred at the left bronchial stump. The fistula was successfully covered with major omentum. The mid-descending thoracic aortic aneurysm due to blunt chest trauma is rare. The traumatic aortic aneurysms commonly occur aortic isthmus or ascending aorta. Initial diagnosis of traumatic mid-descending thoracic aortic aneurysm is often missed or delayed. Careful follow up is need and when an abnormality is revealed by chest roentgenogram, computed tomogram and aortogram should be obtained to make diagnosis of chronic traumatic aneurysm.

Aorta, Thoracic↗
PubMed1992

[MRSA pyothorax due to bronchopleural fistula after grafting and pneumonectomy for traumatic aneurysm of the thoracic aorta--a successful treatment by open drainage and omentopexy].

Treatment of postpneumonectomy pyothorax due to bronchopleural fistula (BPF) is troublesome, especially with methicillin-resistant staphylococcus aureus (MRSA) infection. Moreover, in a bypass-grafting case, the management becomes more complicated. We reported a successful treated case of MRSA pyothorax due to BPF after grafting and pneumonectomy. In a 48-year-old woman performed grafting and pneumonectomy for traumatic aneurysm of the thoracic aorta, MRSA pyothorax due to BPF occurred. BPF was successfully closed by fibrin-glueing under bronchofiberscopy. However pyothorax was not improved by thoracic irrigation for a month. Therefore, open pleural drainage underwent. At the same time, bronchial stump and graft surface was covered with the omental pedicle flap. The open wound had become sterile in two months, and the thoracic window was closed three months after the open drainage.

Aorta, Thoracic↗
PubMed1992

[A resected case of thymolipoma].

We reported a resected case of thymolipoma, which has been hardly experienced. The patient was 21-year-old female and consulted a doctor for general fatigue. Chest roentgenogram revealed a mass-like shadow at the right lower mediastinum, which was suspected mediastinal tumor. The mass of right anteroinferior mediastinum, which was clearly shown by chest CT scan and MRI, was continued to the right lobe of the thymus. Under a diagnosis of anterior mediastinal tumor, operation was carried out. The tumor, which was 10 x 8 x 7 cm in diameter and 160 g in weight, was removed together with right lobe of the thymus. Histological diagnosis of thymolipoma was obtained from the resected specimen.

Adult↗