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Masayoshi Inoue

Publications and source records attributed to Masayoshi Inoue.

At least 37 records · Page 2Linked to original sources
PubMed2005

Surgical results for chronic empyema using omental pedicled flap: long-term follow-up study.

BACKGROUND: Successful treatment of chronic empyema remains a challenge for thoracic surgeons. Herein, we report our 17 years of experience with the omental pedicled flap procedure for management of chronic empyema secondary to pulmonary tuberculosis. METHODS: We retrospectively reviewed the surgical results of 23 patients who underwent surgical treatment for chronic empyema using an omental pedicled flap from 1987 to 2003. RESULTS: The subjects were 20 men and 3 women (mean age, 58.1 years) with average % vital capacity (VC) and forced expiratory volume in 1 second (FEV1) values of 48.1% and 1.19 L, respectively. Sixteen patients (69.6%) had bronchopleural fistulas and 21 (91.3%) were associated with infection by causative organisms (6 Aspergillus organisms, 4 methicillin-resistant Staphylococcus aureus, 10 others). An open window thoracostomy preceded in 17 patients (72.9%). Eleven patients were treated using an omental pedicled flap with or without a muscle flap, and 12 were treated using an omental pedicled flap with a partial thoracoplasty. There was 1 operation-related death, and clinical success was achieved in 19 patients (82.6%), in whom pulmonary function did not decrease significantly. During long-term follow-up, 5 patients died of respiratory failure, and their mean postoperative %VC and FEV1 values were 30.1% and 0.76 L, respectively. CONCLUSIONS: We concluded that the use of an omental pedicled flap for chronic empyema was effective even in cases with active infection, and did not compromise pulmonary function. Further, an additional thoracoplasty may completely obliterate the dead space, although indications should be referenced to preoperative pulmonary function.

Aged↗
PubMed2005

Long-term graft patency after replacement of the brachiocephalic veins combined with resection of mediastinal tumors.

OBJECTIVE: We sought to investigate the correlation between type of vascular reconstruction and long-term graft patency after replacement of brachiocephalic veins combined with resection of mediastinal malignancies. METHODS: Eighteen patients underwent surgical resection of tumors and the superior vena cava with concomitant vascular reconstruction using ringed polytetrafluoroethylene grafts. Graft patency was verified by means of venography or contrast-enhanced computed tomography at time points ranging from 3 to 77 months (median, 33 months) postoperatively. RESULTS: Seven patients underwent sole reconstruction of the right brachiocephalic vein, with occlusion observed in only 1 patient. In 6 patients who underwent reconstruction of the bilateral brachiocephalic veins with 2 separate grafts, the grafts remained patent in 2, whereas 4 patients experienced occlusion of one of the two grafts yet remained asymptomatic. Both patients who underwent reconstruction with a Y graft experienced left brachiocephalic vein graft occlusion. In the 3 patients who underwent reconstruction of a left brachiocephalic vein, the graft became occluded, and superior vena cava syndrome developed in 2 of these patients. CONCLUSION: When replacing the superior vena cava, reconstruction of a left brachiocephalic vein alone results in a significant rate of occlusion and development of superior vena cava syndrome. Thus we advocate sole right brachiocephalic vein reconstruction or bilateral brachiocephalic vein reconstruction in this setting, and separate reconstruction of the veins is preferable to use of a Y graft.

Adolescent↗
PubMed2005

Genomic relationships among Nicotiana species with different ploidy levels revealed by 5S rDNA spacer sequences and FISH/GISH.

We used the intergenic spacer sequences of the 5S ribosomal RNA genes (5S rDNA) to obtain insights into the genomic origin of putative amphidiploid/tetraploid species with 2n = 48 and their descendants in Nicotiana. Amplification of the spacer sequences and subsequent multiple alignment using the consensus sequences from each species, showed that two Australian species shared common large deletions, suggesting that the origin of the 5S rDNA is closely related in these species. Comparison of the spacer sequences with those from diploid (2n = 24) Nicotiana species made it possible to detect some groups consisting of the sequences from the 2n = 24 and 2n = 48 level species. Chromosomal localizations of the 5S rDNA arrays were similar in most groups. The relationships suggested by the 5S rDNA were also assessed at the genome level by using genomic in situ hybridization. We showed that the grouping based on the 5S rDNA spacer sequence reflects high genomic homology between 2n = 24 and 2n = 48 level species. As a result, the putative polyploid species such as N. debneyi, N. quadrivalvis, and N. africana were suggested to involve the close relatives of the diploid species such as N. glauca, N. obtusifolia and N. sylvestris, and N. langsdorffii, respectively, in their speciation. Our results are generally in agreement with the relationships previously suggested by morphological and cytogenetic observations, and some novel relationships were also revealed.

Base Sequence↗
PubMed2005

Comparative radiation tolerance based on the induction of DNA double-strand breaks in tobacco BY-2 cells and CHO-K1 cells irradiated with gamma rays.

Higher plants are generally more tolerant to ionizing radiation than mammals. To explore the radiation tolerance of higher plants, the induction of DNA double-strand breaks (DSBs) by gamma rays was investigated in tobacco BY-2 cells and compared with that in Chinese hamster ovary (CHO)-K1 cells as a reference. This is the first examination of radiation-induced DSBs in a higher plant cell. The resulting DNA fragments were separated by pulsed-field gel electrophoresis and stained with SYBR Green I. The initial yield of DSBs was then quantified from the fraction of DNA fragments shorter than 1.6 Mbp based on the assumption of random distribution of DSBs. The DSB yield in tobacco BY-2 cells (2.0 +/- 0.1 DSBs Gbp(-1) Gy(-1)) was only one-third of that in CHO-K1 cells. Furthermore, the calculated number of DSBs per diploid cell irradiated with gamma rays at the mean lethal dose was five times greater in BY-2 cells (263 +/- 13) than in CHO-K1 cells. These results suggest that the radiation tolerance of BY-2 cells appears to be due not only to a lower induction of DNA damage but also to a more efficient repair of the induced DNA damage.

Animals↗
PubMed2005

Effects of surface wetness of etched dentin on bonding durability of a total-etch adhesive system: comparison of conventional and dumbbell-shaped specimens.

The dentin bonding durability of a total-etch adhesive system (Prime & Bond NT) was investigated by tensile bond test using conventional and dumbbell-shaped specimens. Two bonding techniques were compared. After etching and rinsing, dentin surface was either blotted by cotton ball (wet-bonding) or air-dried (dry-bonding) before bonding agent was applied. The bond strength of wet-bonding specimens was significantly higher than that of dry-bonding for both conventional and dumbbell-shaped specimens after one day. The bond strength of wet-bonded conventional specimens did not decrease after two years of water immersion, but cohesive failure in demineralized dentin was observed after two years. Wet-bonded dumbbell-shaped specimens showed cohesive failure within demineralized dentin after only one day. The bond strength of dry-bonded conventional specimens decreased significantly after one year, and cohesive failure in demineralized dentin was confirmed after three months. As for dry-bonded dumbbell-shaped specimens, they showed cohesive failure in demineralized dentin after one month. The results of the present study showed that the bonding durability of dry-bonded Prime & Bond NT restorations was lower than that of wet-bonded restorations. Further, by using tensile bond test, cohesive failure in demineralized dentin was detected earlier in dumbbell-shaped specimens than in conventional specimens.

Acid Etching, Dental↗
PubMed2004

Benefits of surgery for patients with pulmonary metastases from colorectal carcinoma.

BACKGROUND: A pulmonary metastasectomy for colorectal carcinoma is a generally accepted procedure, although several prognostic predictors have been reported. The aim of this study is to define the patients who benefit from pulmonary metastasectomy for colorectal carcinoma. METHODS: Retrospective survival analysis was performed using 128 patients who underwent curative pulmonary resection. RESULTS: The overall 5-year survival rate was 45.3%. Univariate analysis showed the number of metastases, location (unilateral or bilateral), prethoracotomy carcinoembryonic antigen (CEA) level, hilar or mediastinal lymph-node metastasis, and Dukes' stage to be considerable prognostic factors. Among these, Dukes' A for the primary lesion and unilateral pulmonary metastasis were shown to be independent predictors of longer survival by multivariate analysis (p = 0.0093 and p = 0.0182, respectively). In patients treated with both pulmonary and hepatic metastastasectomies, a better prognosis was observed in those who received metachronous resection. Recurrence after a pulmonary metastasectomy frequently occurred in the thorax and the 3-year survival rate was 44.6% in patients who underwent a repeat thoracotomy. CONCLUSIONS: Patients with unilateral metastasis and Dukes' A for the primary tumor benefit most from the resection of pulmonary metastasis from colorectal carcinoma. Further, the number of metastases, prethoracotomy CEA level, and hilar or mediastinal lymph-node involvement should be considered to determine the operative indication. Finally, periodic follow-up examinations for thoracic recurrence should be carefully performed as these patients may have a heightened risk of requiring a repeat thoracotomy.

Adenocarcinoma↗
PubMed2004

Thymic carcinoma. Clinical institutional experience with 15 patients.

OBJECTIVE: We retrospectively evaluated 15 patients with thymic carcinoma treated with various modalities and investigated overall management of this disease. METHODS: From 1983 to 2003, we treated 15 patients with thymic carcinoma (12 squamous cell carcinomas, 2 undifferentiated carcinomas and one adenocarcinoma). According to Masaoka's staging system, they consisted of 2 at stage II, 5 at stage III, 4 at stage IVa and 4 at stage IVb. RESULTS: Ten patients were histologically diagnosed preoperatively, and 5 patients underwent an exploratory procedure under the diagnosis of thymoma or benign teratoma. Complete resection was performed in 9 patients (2 stage II, 5 stage III and 2 stage IVa), which included 4 patients who received induction therapy, 4 who received postoperative radiation therapy, and 1 who received postoperative chemotherapy. Six patients with unresectable tumors were treated by irradiation (40-60 Gy) with or without chemotherapy. The median survival was 13 months for patients without resection, and 57 months for patients with a complete resection. Total 3-year and 5-year survival rates were 51.9 and 39.0%, respectively. CONCLUSIONS: We concluded that a complete resection is mainstay of therapy when possible, but chemoradiation therapy being potential benefit in the management of thymic carcinoma. However, considering the high prevalence of advanced stage patients, to establish the effective regimen of induction therapy in the additional multicenter trials should be mandatory.

Adenocarcinoma↗
PubMed2004

Results of surgical intervention for p-stage IIIA (N2) non-small cell lung cancer: acceptable prognosis predicted by complete resection in patients with single N2 disease with primary tumor in the upper lobe.

OBJECTIVES: Non-small cell lung cancer with mediastinal lymph node involvement is a heterogeneous entity different from single mediastinal lymph node metastasis to multiple nodes or extranodal disease. The objective of this study was to identify the subpopulation of patients with N2 disease who can benefit from surgical intervention. METHODS: We reviewed 219 consecutive patients with N2 non-small cell lung cancer treated with a thoracotomy between November 1980 and June 2002 and retrospectively analyzed 154 of those who had p-stage IIIA disease and underwent a complete resection. Age, sex, side (right or left), histology, location (upper or middle-lower lobe), tumor size, c-N factor, and N2 level (single or multiple) were used as prognostic variables. RESULTS: The 3- and 5-year survivals were 45.3% and 28.1%, respectively, in patients with p-stage IIIA (N2) disease. Survival for those with single N2 non-small cell lung cancer was significantly better than in those with multiple N2 disease (P =.0001), and patients with a tumor in the upper lobe showed a significantly longer survival than those with middle-lower lobe involvement (P =.0467). The 3- and 5-year survivals for patients with single N2 disease with a primary tumor in the upper lobe were 74.9% and 53.5%, respectively. A multivariate analysis with Cox regression identified 5 predictors of better prognosis: younger age, squamous cell carcinoma as determined by histology, primary tumor location in the upper lobe, c-N0 status, and a single station of mediastinal node metastasis. CONCLUSION: Our results suggest that of the heterogeneity of N2 diseases, patients with single N2 disease with non-small cell lung cancer in the upper lobe are good candidates for pulmonary resection.

Adenocarcinoma↗
PubMed2003

Correlating genetic aberrations with World Health Organization-defined histology and stage across the spectrum of thymomas.

Thymomas are thymic epithelial tumors. Because most of them are rich in nonneoplastic T-cells, recurrent genetic aberrations have been reported only in the rare, lymphocyte-poor WHO types A, B3, and C. We have now investigated virtually the whole spectrum of thymomas, including the commoner types AB and B2, microdissecting or culturing neoplastic cells from these lymphocyte-rich thymomas and applying 41 microsatellite markers covering 17 loci on 10 chromosomes. In 28 cases, comparative genomic hybridization data were available. Apart from type A, there was striking heterogeneity between thymomas. Allelic imbalances were seen in 87.3% of the 55 cases, and MSI in 9.9%. Losses of heterozygosity (LOHs) were much the commonest aberration. Overall, they were most prevalent at four regions on chromosome 6. Aberrations elsewhere, affecting mainly 8p11.21 and 7p15.3, suggested a cortical footprint because they recurred only in the thymopoietically active type AB and B thymomas. LOHs were also seen at the adenomatous polyposis coli (APC) locus (5q21-22) in subsets of these thymomas, whereas combined LOHs at the APC, retinoblastoma (13q14.3), and p53 (17p13.1) loci were confined to a subset of B3 thymomas that had possibly evolved from APC-hemizygous B2 thymomas by tumor progression; indeed, thymomas combing B2 plus B3 features are common. Notably, some AB and B thymomas shared LOHs despite their nonoverlapping morphology and different clinical behavior. Finally, allelic imbalances at 8p11.21 and 16q22.1 (CDH1) were significantly more frequent in stage IV metastatic thymomas. We conclude that the WHO-defined histological thymoma types generally segregate with characteristic genetic features, type A thymomas being the most homogeneous. Many findings support the view that B2 and B3 thymomas form a continuum, with evidence of tumor progression. However, other findings imply that types A and AB are biologically distinct from the others, any potential invasiveness being severely restricted by a medullary commitment in the precursor cell undergoing neoplastic transformation.

Cells, Cultured↗
PubMed2003

Immunohistochemical analysis of resected clinical stage I pulmonary adenocarcinomas with high preoperative levels of serum carcinoembryonic antigen.

BACKGROUND: Clinical stage I pulmonary adenocarcinoma (AD) patients with persistently high serum carcinoembryonic antigen (CEA) levels after surgery have a poor prognosis. Although CEA staining pattern is reported to be a prognostic indicator for patients with colorectal cancer, the relationship with lung cancer is unclear. METHODS: One hundred eighteen patients with clinical stage I AD underwent surgery from 1993 to 1997. Of them, 19 (16%) patients with a high preoperative serum level of CEA and 19 randomly selected control patients with preoperatively normal CEA were studied. CEA staining of tumor specimens from each of the 38 patients was performed, and the staining patterns were then classified into two types: apical and diffuse. RESULTS: Patients with normal postoperative serum CEA levels (group HN, n = 13) had a 5-year survival rate higher than those with persistently high postoperative serum CEA (group HH, n = 6). In a comparison between the two groups, apical patterns (n = 10) were only seen in group HN, and those who demonstrated an apical CEA staining pattern had a 5-year survival rate (5-YSR) of 80% as compared with 13% for those HN patients with only a diffuse pattern (p = 0.01). In the control group, 16 (84%) patients had an apical staining pattern and the other 3 patients showed no staining. CONCLUSIONS: Patients with normalized serum CEA levels had a high chance of showing an apical staining pattern, which may be a very good prognosis predictor for patients with high preoperative levels of CEA.

Adenocarcinoma↗
PubMed2003

The immunologic role of thymectomy in the treatment of myasthenia gravis: implication of thymus-associated B-lymphocyte subset in reduction of the anti-acetylcholine receptor antibody titer.

BACKGROUND AND PURPOSE: Thymectomy is generally accepted as the major option of treatment for myasthenia gravis. To elucidate the biological role of thymectomy in the treatment of myasthenia gravis, the immunologic characteristics of the thymus was studied in association with the postoperative kinetics of the anti-acetylcholine receptor antibody titer. MATERIALS AND METHODS: Thirty-four patients with nonthymomatous myasthenia gravis who had positive anti-acetylcholine receptor antibody titer and undergoing extended thymectomy were subjected to the study. Reduction of anti-acetylcholine receptor antibody titer was evaluated in terms of the proportion of anti-acetylcholine receptor antibody titer at 1 year after thymectomy to that before the operation. The numbers of B lymphocytes (CD19(+) cells) and the germinal center B lymphocytes (CD19(+)CD38(high) cells) present in 1 g of the thymic tissue were calculated by flow cytometry. RESULTS: The proportion of anti-acetylcholine receptor antibody titer at 1 year after thymectomy ranged from 27.5% to 150%. The numbers of B lymphocytes and the germinal center B lymphocytes in 1 g of the thymic tissue ranged from 0.19 x 10(6)/g to 162.8 x 10(6)/g and from 0.09 x 10(6)/g to 33.4 x 10(6)/g, respectively. The proportion of anti-acetylcholine receptor antibody titer at 1 year after thymectomy had a significant inverted correlation with the number of B lymphocytes (P =.002) as well as that of the germinal center B lymphocytes (P =.007). CONCLUSION: Effectiveness of thymectomy was dependent on predominance of B lymphocytes and the germinal center B lymphocytes in the thymus, suggesting that one of the biological roles of thymectomy in the treatment of myasthenia gravis is removing the thymus-associated germinal centers.

ADP-ribosyl Cyclase↗
PubMed2003

Development of an ion microbeam system for irradiating single plant cell[s].

An ion microbeam system for irradiating single plant cells was developed to analyze exact biological effects of ion beams. Tobacco BY-2 protoplasts were used as a model of single plant cells. Protoplasts were cultured in thin agarose medium on a specially designed irradiation-vessel, which has a CR-39 nuclear track detector (a 100-micrometer thick sheet). The colony formation rate of unirradiated protoplasts was 22.7 +/- 6.7% (mean +/- SE of 3 different experiments) after a month of culture. Protoplasts were irradiated with programmed numbers of 18.3 MeV/u carbon ions that had been collimated by a 20-micrometer phi micro-aperture. After the irradiation, the positions within the protoplasts that were hit with ions were accurately determined by etching the CR-39 sheet in 13.4M KOH solution at 27 degrees centigrade for 9 h. The hit rate of the carbon ion microbeam, i.e., the percent of the ion particles that hit the protoplast that they were aimed at, was 56.9 +/- 2.4% (mean +/- SE of 7 different replications).

Carbon↗
PubMed2002

Video-assisted thoracoscopic bullectomy for spontaneous pneumothorax in a Swyer-James syndrome patient.

We treated a 15-year-old patient with spontaneous pneumothorax associated with Swyer-James syndrome using video-assisted thoracoscopic surgery (VATS). Thoracic computed tomography showed hyperlucent areas in the bilateral lungs. Due to major air leakage continuing for a week, we conducted VATS bullectomy. Because the opposite lung suffered hypoplasia, intermittent bilateral pulmonary ventilation was required to sustain an adequate PaO2 in arterial blood gas analysis during surgery. Because of recurrent pneumothorax, we performed reoperation 10 months later, finding a few newly generated bullae. To the best of our knowledge, this is the first report of VATS used to treat a Swyer-James syndrome patient with pneumothorax.

Adolescent↗
PubMed2002

Steroid therapy without primary dose escalation for postthymectomy crisis in 2 thymomatous myasthenia gravis patients.

We report 2 cases of thymomatous myasthenia gravis associated with postoperative crisis and medicated with steroid therapy using prednisolone without primary dose escalation. Two women, a 38 years old and the other 64 years old, underwent extended thymectomy under the diagnosis of myasthenia gravis associated with invasive thymoma. Bulbar symptoms in both were severe despite preoperative anticholinesterase medication. Myasthenic crises with an antiacetylcholine receptor antibody (anti-AchR Ab) elevation were encountered in the postoperative clinical course. Daily administrations of a large amount of prednisolone without primary dose escalation and the subsequent tapering therapy effectively improved myasthenic symptoms and decreased their anti-AchR Ab titer. We also discuss difficulties in treatment in these cases.

Adult↗
PubMed2002

Chromosome 6 suffers frequent and multiple aberrations in thymoma.

Thymoma is the most frequent tumor arising in human thymus. In this study, we performed a detailed mapping of deleted regions on chromosome 6 shown previously to harbor the most frequent genetic aberrations in this cancer. We analyzed 40 thymomas using 41 microsatellites. Two hundred ninety-four (23.5%) of 1253 informative genotypes showed loss of heterozygosity (LOH), only 39 (2.4%) were positive for microsatellite instability (MSI). Genetic aberrations on chromosome 6 were found in 31 of 40 cases (77.5%) in five hot spots. The most frequent LOHs (48.6%) occurred in region 6q25.2 within a 0.7-Mb interval flanked by markers D6S441 and D6S290. Another hot spot showing LOH in 32.4% of tumors was located between markers D6S442 and D6S1708 (0.4 Mb apart) on 6q25.2-25.3, just 1.1 Mb from the D6S441-D6S290 deletions. The third hot spot (30%) showing LOH appeared in region 6p21.31 including the MHC locus (markers D6S1666-D6S1560, 1 Mb apart). The fourth hot spot (26.3%) was detected on 6q14.1-14.3 (D6S1596-D6S284, 5.2 Mb apart). Some tumors (21.6%) showed LOHs within a fifth hot spot on 6q21 (D6S447-D6S1592, 0.3 Mb apart). Thus, several tumor suppressor genes on chromosome 6 seem to be involved in the pathogenesis of thymoma.

Chromosome Aberrations↗