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K Okabayashi

Publications and source records attributed to K Okabayashi.

At least 55 records · Page 3Linked to original sources
PubMed1997

[Video-assisted thoracic surgery for lung cancer].

Video-assisted thoracic surgery (VATS) has been applied to treat patients with various pulmonary diseases. Recent advances in video endoscopic instruments have been enabled radical resection of pulmonary malignancies as minimally invasive surgery. Forty patients with primary lung cancer underwent several types of lung resection in the past 3 years at out unit. Of these, twenty-seven anatomical pulmonary resections were performed using VATS. Peripherally located, early-stage lung cancer is thought to be a potential candidate for curative surgery with video-assisted lobectomy. Although there are some pitfalls with VATS, sufficient mediastinal lymph node dissection is thought to be possible. Additionally, intrathoracic hyperthermic chemotherapy using video-assisted thoracoscope for both pleural disseminated lesion and malignant pleural effusion is described.

Cisplatin↗
PubMed1997

Video-assisted thoracoscopic lobectomy for treating lung cancer.

Our objective was to evaluate the usefulness and safety of video-assisted thoracoscopic surgery (VATS) for performing pulmonary lobectomy in 11 patients with clinical NO stage I primary non-small-cell lung cancer compared with 11 patients who underwent a conventional thoracotomy. Treatment was switched to conventional thoracotomy in three VATS patients because of the involvement of interlobar nodes or incomplete lobar fissure. None of the eight VATS patients died or experienced serious complications during 12 months of follow-up. There were no significant differences in the intraoperative blood loss, duration of operation, or duration of chest tube drainage between the VATS group and the standard lobectomy group. We conclude that although VATS lobectomy appears to be safe for use in managing patients with primary lung cancer, it does not seem to offer any advantages over standard lobectomy.

Adenocarcinoma↗
PubMed1997

[Complications of thoracoscopic surgery for spontaneous pneumothorax].

We reviewed the cases of 122 patients with primary spontaneous pneumothorax who underwent thoracoscopic surgery at our institution between 1992 and 1995. In 9 cases, thoracotomy became necessary because of severe adhesions (3 cases), large foci (3 cases), and unrecognized foci (3 cases). Complications occurred in 17 cases: collapse in 1 patient after removal of the thoracic drain, persistent air leakage (> 7 days) in 2 patients, and recurrent pneumothorax in 14 patients. There were no significant differences between the recurrent and non-recurrent cases in age, sex location of bullae, past history of pneumothorax, operating time, intraoperative blood loss, or duration of chest tube drainage after surgery. The interval between onset and consult was significantly longer in recurrent cases than in non-recurrent cases, and the number of patients who required chest tube drainage before surgery was significantly higher in recurrent cases. Reoperation was performed in 9 cases. Bullaes that were not detected during the first surgery were found in the 7 of these cases. The recurrent cases in our study were regarded as resulting from a lack of surgical skill that may improved with increasing surgical experience. The Brinkman index was significantly higher in recurrent cases. Smoking and air-leakage before surgery may be risk factors for recurrence following thoracoscopic surgery for spontaneous pneumothorax.

Adolescent↗
PubMed1996

Attenuation of rat lung isograft reperfusion injury with a combination of anti-ICAM-1 and anti-beta2 integrin monoclonal antibodies.

Four different combinations of monoclonal antibodies against rat ICAM-1, CD-11a, and CD-18 were utilized to determine the relative importance of LFA-1, Mac-1, and ICAM-1 in a rat model of severe lung allograft reperfusion injury. Negative control animals were given phosphate buffered saline (the carrier solution for the antibodies), while positive control animals were rendered neutropenic by the administration of a polyclonal mouse IgG. Antibodies were given with the donor lung flush, prior to left lung graft reperfusion, or both. Isolated graft function was determined 24 hr after implantation by arterial blood gas (ABG), and after sacrifice the native and transplanted lungs underwent bronchoalveolar lavage for alveolar protein quantitation, cell count and differential, and myeloperoxidase assay. Additionally, whole lung homogenates were assayed for myeloperoxidase activity. We found that the combination of anti-ICAM-1 (1 mg/kg) added to the donor lung flush, and anti-CD11a, anti-CD18, and anti-ICAM-1 (2 mg/kg i.v. of each) given to the recipient prior to reperfusion, resulted in significantly improved lung graft pAO2 by ABG, and decreased alveolar protein, cell count, and myeloperoxidase activity compared with control animals. Improvement was less than that seen in the neutropenic recipients, however. We conclude that LFA-1, Mac-1, and ICAM-1 are all important adhesion molecules in lung allograft reperfusion injury--yet even with antibody blockade of all three there are additional mechanisms allowing for neutrophil influx into the lungs.

Animals↗
PubMed1996

Secretory production of recombinant urokinase-type plasminogen activator-annexin V chimeras in Pichia pastoris.

To produce a thrombi-targeting plasminogen activator, we expressed a fused gene that contains a modified pre-sequence of Mucor pussilus rennin (MPR) followed by a chimeric gene of single-chain urokinase-type plasminogen activator (scu-PA)::annexin V (AV). The fused gene was ligated into an integrative vector, under the control of the alcohol oxidase 1 (AOX1) promoter (p), and transformed into Pichia pastoris. Transformants were monitored for the secretion of fibrinolytic activity. The highest expressing clone, HB225, secreted as much as 600 international units (IU) of fibrinolytic activity per ml of culture medium under optimal conditions. It contained three tandem copies of the full-size vector disruptively integrated into the AOX1 sequence. Western blot analysis revealed that the secreted chimera was highly susceptible to proteolysis. Addition of excess amino acids (aa) to the culture medium minimized the degree of proteolysis. Two major species of chimera, 85 and 65 kDa, were then isolated from the culture medium. The former was the intact form consisting of a single-chain and showing full enzyme activity after activation by plasmin. The latter was an enzymatically processed form consisting of two chains held by a disulfide bond, having full enzyme activity without activation. Both chimeras exhibited calcium-dependent phospholipid (PL)-binding affinities similar to the parent AV.

Amino Acid Sequence↗
PubMed1996

cDNA cloning and expression of the Xenopus laevis vitellogenin receptor.

A Xenopus laevis oocyte cDNA library was screened with a PCR-generated X. laevis vitellogenin (VTG) receptor probe and a 3.6 kb cDNA clone containing the entire open reading frame, and 5' and 3' noncoding regions were isolated. The deduced amino acid sequence was 72% homologous to the chicken VLDL/VTG receptor, and the characteristic domains were highly conserved. Ligand binding analysis confirmed that the cloned receptor was Xenopus VTG-specific. Although Northern blotting analysis revealed that this gene was expressed as a major transcript of 3.6 kb in Xenopus ovary, weak but significant expression was observed in other tissues by RT-PCR analysis. The fact that major expression of the gene occurs in the ovary suggests that it has an important function in this organ.

Amino Acid Sequence↗
PubMed1996

Postoperative complications after pneumonectomy for treatment of lung cancer: multivariate analysis.

The charts of 62 patients with primary lung cancer who underwent a pneumonectomy at our department from 1979 through 1992 were reviewed for the evaluation of postoperative morbidity and mortality. The 30-day mortality was 3/62 or 4.8%. Postoperative complication occurred in 37 of 62 patients (60%). The most common complication was a supraventricular tachyarrythmia. A major complication, which was defined as one necessitating re-thoracotomy or one which caused death, occurred in 19 patients (31%). We analyzed 43 perioperative variables for their predictive value of postoperative morbidity and mortality. Univariate analysis indicated that an elevated serum LDH, low predicted forced vital capacity, low predicted forced expiratory volume in 1 sec (FEV1) were significantly associated with the occurrence of a major complication. A multivariate logistic regression model indicated that a high LDH level, a low predicted FEV1 and no extubation following surgery were associated independently with a postoperative major complication. Since only the complete removal of a tumor offers a chance for cure for the treatment of non-small cell lung cancer, it is sometimes necessary to perform a pneumonectomy for these high-risk patients. Patients identified as being at high risk of a major complication should be candidates for intensive preoperative evaluation and perioperative care.

Adult↗
PubMed1996

Secretion of a variant of human single-chain urokinase-type plasminogen activator without an N-glycosylation site in the methylotrophic yeast, Pichia pastoris and characterization of the secreted product.

Human single-chain urokinase-type plasminogen activator without an N-glycosylation site (scu-PA-Q302) was produced in the methylotrophic yeast, Pichia pastoris using the shortened prepeptide sequence of a fungal aspartic proteinase, Mucor pusillus rennin (MPR). The level of urokinase-type plasminogen activator (u-PA) immunoreactive material in YPM medium was 0.47 mg/l; however, most of the secreted product had been processed to smaller polypeptides. The N-terminal amino acid sequence of major species was identical to that of the low molecular weight two-chain u-PA. Some approaches to minimizing the proteolysis of scu-PA-Q302 were attempted. Addition of Triton X-100, L-arginine and ammonium phosphate to the YPM medium minimized the proteolysis of scu-PA-Q302 and increased the yield of immunoreactive material to approximately 5 mg/l. Use of proteinase A- or proteinase B-deficient strains of yeast did not reduce the degradation. Co-expression of scu-PA-Q302 and urinary trypsin inhibitor resulted in partial reduction of the major species of proteolysis. Scu-PA-Q302 was purified from the culture supernatant of the improved medium by two successive chromatographies on Phenyl-Sepharose and S-Sepharose. The purified protein had a molecular weight of 47 kDa. It did not contain detectable N-linked oligosaccharides, but contained O-linked oligosaccharides attached to the light chain. N-terminal amino acid sequencing of the purified preparation showed that the shortened prepeptide sequence of MPR was correctly processed by the Pichia yeast. Scu-PA-Q302 closely resembles natural scu-PA with respect to its enzymatic activity against the chromogenic substrate S-2444 and its in vitro fibrinolytic properties.

Arginine↗
PubMed1996

Pentoxifylline in flush solution improves early lung allograft function.

BACKGROUND: Postischemic ischemia reperfusion injury is a frequent and unpredictable problem in clinical lung transplantation. Pentoxifylline (PTX) has a number of effects that could decrease reperfusion injury: reduced neutrophil adhesion to endothelium, decreased production of tumor necrosis factor, decreased platelet aggregation, and increased production of vasodilatory prostaglandins by vascular endothelium. We have demonstrated previously that PTX administered before storage and again during reperfusion reduced lung reperfusion injury. The purpose of the present study was to determine whether these observations were storage or reperfusion effects. METHODS: Fourteen canine left lung allotransplantations were performed. Donor lungs were flushed with modified Euro-Collins solution and stored for 24 hours at 1 degree C. Immediately after transplantation, the contralateral right main pulmonary artery and bronchus were ligated to assess isolated allograft function. Hemodynamic indices and arterial blood gas analysis (inspired oxygen fraction 1.0) were assessed for 6 hours before sacrifice. Allograft myeloperoxidase activity was assessed. Bronchoalveolar lavage fluid was obtained from the allograft middle lobe for neutrophil counts. The animals were divided into three groups based on the timing of PTX administration. Group 1 (n = 5) animals received no PTX. Group 2 (n = 4) animals received PTX (20 mg/kg) just before reperfusion as well as continuous infusion (0.1 mg x kg-1 x min-1) during the assessment period. In group 3 (n = 5), donor lungs received PTX (200mg/L) in the flush solution only. RESULTS: Superior gas exchange was noted in the lungs receiving PTX only in the flush solution (group 3). Myeloperoxidase activity in group-3 allografts was significantly reduced. In addition, protein levels and neutrophil counts in the bronchoalveolar lavage fluid were significantly reduced in group-3 allografts. CONCLUSIONS: Pentoxifylline ameliorates lung allograft reperfusion injury when administered in the flush solution. Our data suggest that PTX will prevent graft endothelial dysfunction during 24-hour cold ischemic storage and consequently will prevent neutrophil activation and migration into lung tissue.

Analysis of Variance↗
PubMed1996

Reconstruction of trachea and carina with immediate or cryopreserved allografts in dogs.

BACKGROUND: Grafting is required when primary reconstruction of a tracheocarinal defect is not feasible. To determine the viability of and the nature of the healing process occurring in the cryopreserved graft, we performed tracheocarinal transplantation in dogs. METHODS: We performed 32 tracheocarinal reconstructions in dogs using autotransplanted, immediately transplanted, or cryopreserved allografts. The viability of each graft was evaluated serially by fiberoptic macroexamination and by measurement of the tracheal mucosal blood flow using a hydrogen clearance method. In group A (n = 8), the tracheal carina was removed and reimplanted immediately. In group B (n = 8), the tracheocarina was allotransplanted immediately after harvest. In group C (n = 8), allotransplantations were performed using grafts cryopreserved for 1 to 3 weeks by freeze-drying. In group D (n = 8), we attempted to achieve immunosuppression-free transplantation with the cryopreserved allografts. RESULTS: Sufficient viability and good healing (6/8, 75%) occurred in the dogs with cryopreserved tracheocarinal allotransplants. Three of 8 dogs (38%) with cryopreserved allotransplants survived for 25 to 57 days without immunosuppression. CONCLUSIONS: The cryopreservation of tracheocarinal allografts for 3 weeks without the use of a preservative solution was shown to be feasible. Cryopreservation prolonged the survival of nonimmunosuppressed allotransplants in dogs.

Animals↗
PubMed1996

Hyperinflation of canine lung allografts during storage increases reperfusion pulmonary edema.

The optimal state of inflation for lung allografts during preservation is not known. We previously showed that hyperinflation of canine lung allografts during storage improved posttransplant graft function as measured during 10 minutes of contralateral pulmonary artery occlusion. However, we have also shown that hyperinflation during storage increases pulmonary capillary permeability. It is possible that short-term total cardiac perfusion through the transplanted left lung (for assessment) may not adequately reproduce the clinical situation. The purpose of this study was to assess the effects of hyperinflation during storage in a canine left single-lung transplantation model in which all perfusion was continuously directed to the graft after implantation. Twenty canine left single-lung transplants were done. The lungs of donor animals were ventilated at a tidal volume of 750 ml and an inspired oxygen fraction of 100%. Donor lungs were flushed with modified Euro-Collins solution and the trachea occluded at end inspiration. For donors in groups I and III, the trachea was sealed at that postinflation volume. In groups II and IV, 200 cc of air was withdrawn from the endotracheal tube under positive pressure and the trachea sealed at the lower tidal volume. Lungs were then extracted and stored at 1 degree C for 12 hours. After the preservation period, left lung transplants were performed. After implantation in all groups, the right pulmonary artery was ligated. In groups I and II, the right bronchus was ligated and in groups III and IV the right bronchus was kept open. Subsequent allograft gas exchange and hemodynamics were assessed during a 6-hour period of reperfusion. After assessment, both lungs were excised, wet/dry lung weight ratio was calculated, and histologic examination was done. During the 6-hour assessment, lungs stored in a state of hyperinflation (groups I and III) showed rapid deterioration of gas exchange. At the final assessment, arterial oxygen tension and alveolar-arterial oxygen gradient of groups I and III were significantly worse than those of groups II and IV (group I versus group II: arterial oxygen tension 87.5 +/- 15.0 versus 373.8 +/- 65.5 mm Hg, alveolar-arterial oxygen gradient 564.4 +/- 13.2 versus 298.6 +/- 69.3 mm Hg, p < 0.05; group III versus group IV: arterial oxygen tension 245.4 +/- 33.0 versus 543.6 +/- 41.8 mm Hg, alveolar-arterial oxygen gradient 392.5 +/- 35.6 versus 120.5 +/- 34.7 mm Hg, p < 0.01). We conclude that donor lung hyperinflation during storage does not provide better posttransplant allograft function when perfusion is limited only to the allograft.

Animals↗
PubMed1996

Inhaled nitric oxide improves lung allograft function after prolonged storage.

Morbidity caused by early allograft dysfunction, manifested by a progressive increase in pulmonary vascular resistance and a decrease in oxygenation, remains a serious problem in lung transplantation. Inhalation of nitric oxide, an essential homeostatic molecule, has been shown to have beneficial effects on a variety of acute lung injuries. The purpose of the present study was to investigate the effect of inhaled nitric oxide on posttransplant function of canine left lung allografts. Fourteen dogs underwent left lung allotransplantation. Donors received systemic heparin and prostaglandin E1 followed by pulmonary artery flush with modified Euro-Collins solution. Donor left lungs were stored for 18 hours at 1 degree C and subsequently implanted. Immediately after reperfusion, the contralateral right main pulmonary artery and bronchus were ligated. The chest was closed and recipients turned to the supine position for the 6-hour assessment period. Hemodynamic and arterial and venous blood gas analyses were made at 15-minute intervals at an inspired oxygen fraction of 1.0 and 5 cm of water positive end-expiratory pressure. Animals were killed at the end of the assessment. Allograft myeloperoxidase activity assays and wet/dry weight ratios were done. In group I (n = 5), nitric oxide gas was administered continuously at concentrations of 60 to 70 ppm before reperfusion and throughout the 6-hour assessment period. In group II (n = 5), nitric oxide administration was initiated at the same concentration after reperfusion injury had developed. Group III animals (n = 4) received no nitric oxide. Significant improvement in gas exchange was apparent in group I. At the end of the 6-hour assessment period, mean arterial oxygen tension was 253.8 +/- 44.7 mm Hg and 114.9 +/- 25.5 mm Hg in groups I and III, respectively (p < 0.05). Group II animals had no improvement in oxygenation with nitric oxide. Systemic hemodynamics were unaffected by nitric oxide. However, an immediate decrease in pulmonary vascular resistance was noted. Group I myeloperoxidase activity was significantly lower than that in control group III (0.24 +/- 0.06 versus 0.36 +/- 0.04 units, respectively; p < 0.05).

Administration, Inhalation↗
PubMed1996

Nodular lymphoid hyperplasia in the lung.

We describe an immunocompetent adult patient presenting with cough and hemoptysis who was found to have a pulmonary mass localized to the right upper lobe. Lobectomy was performed and pathological examination revealed nodular lymphoid hyperplasia (pseudolymphoma) of the bronchus-associated lymphoid tissue.

Aged↗
PubMed1996

[Quality control of surgery in multicenter study--interinstitutional and individual differences].

UNLABELLED: In a prospective randomized controlled trial (PRCT) of adjuvant chemotherapy for gastric cancer patients participated by 6 cancer center hospitals, inter-institutional and inter-individual differences about several factors related to the surgery and remote survivals were analyzed. From 1988 to 1992, 1,049 evaluable patients were enrolled and stratified to 6 groups according to the grade of the serosal invasion and curability, and analyzed statistically. RESULTS: 1) There were no inter-institutional differences about postoperative survival rate, but there were slight differences about patient's background factors and entry policy of each institution. 2) There were no inter-institutional differences about several factors related to the surgery such as operative time, bleeding volume during operation, and the length of the administration periods. 3) There were no inter-individual differences about the length of the administration periods, but there were a little differences about operative time and the volume of hemorrhage. When the PRCT of adjuvant chemotherapy of which the end point is survival would be designed, no inter-institutional differences about remote survival and surgical operation in each institution should be confirmed before starting the trial.

Chemotherapy, Adjuvant↗
PubMed1996

[Iatrogenic injury of tracheobronchial membranous wall].

Tracheobronchial injuries remain uncommon, but they are of great significance, because they can result in death or substantinal functional compromise. Such injuries are mostly from blunt trauma and motor vehicle accidents, but there also is an incidence of penetrating thoracic trauma inclunding iatrogenic accidents. Three cases of iatrogenic injury of tracheobronchial membranous wall were reported. Two cases were tear at the membraneous portion of the left main bronchus and trachea by forceful endotracheal intubation. Another case was tracheal membranous wall injury during operation at blunt dissection for esophageal carcinoma. We reported the emergent managements for iatrogenic injury of tracheobroncheal membranous wall in differents 3 ways. We should select the best treatment according to the condition of the patients and situation of the injury.

Aged↗
PubMed1996

[Dynamic stent useful for trachocarinal stenosis due to lung cancer].

In this study, a new tracheobronchial stent was used for treating a patient with tracheocarinal stenosis due to lung cancer. The patient was 41 year-old male with lung mass in the right upper lobe and metastatic mediastinal lymph node which caused tracheocarinal stenosis. The stent was introduced under general anesthesia with a jet ventilator. The respiratory condition of the patient could be controlled fairly well, and the ventilation tube didn't interfere with the stenting. The stent was a tracheobronchial silicone stent provided with a flexible posterior membrane and tracheal cartilage-shaped steel struts. Coughing is less difficult than other stents owing to better design. This patient has been able to cough up sputum from the day of the operation and there has been no need for bronchoscopic examination for removal of secretions.

Adenocarcinoma↗
PubMed1995

Randomized study with mitomycin C + 5-fluorouracil+cytosine arabinoside (MFC)+5-fluorouracil, MFC+tegafur and uracil (UFT), and MF+UFT in advanced gastric cancer: interinstitutional differences in a multicenter study in Japan.

In a phase III randomized trial of adjuvant chemotherapy for gastric cancer, interinstitutional differences were analyzed. A trial of three regimens: mitomycin C, 5-fluorouracil(5-FU) and CA (MFC) + continuous oral 5-FU (Group C); MFC + continuous oral UFT(tegafur and uracil) (Group B); and MF + UFT (Group C) after operation was conducted in 466 patients with gastric cancer (stage II and III) at four hospitals in Japan (CIH, CAD, ACC and NCC). Patients were stratified by the institution, stage, and tumor size (8 cm ><). The 5-year survival rates were in the order of Group A (79.0%) > B (70.0%) > C (61.0%) (P = 0.1228) in total, A (95.0%) > B (80.0%) > C (58.0%) (P < 0.05) at CAD (82 patients), A > C > B at CIH (215), C > A > B at ACC (95), and B > A > C at NCC (78). The survival rate of patients with S2(serosal exposure), 8 cm < and N0-1 cancer was higher at CIH than at the other institutions. The interinstitutional differences in patient characteristics and surgical technique were more powerful than the differences among the three groups.

Administration, Oral↗