Biomedical subjects

J Amano

Publications and source records attributed to J Amano.

At least 19 recordsLinked to original sources

PubMed2006

The effects of a neutrophil elastase inhibitor on the postoperative respiratory failure of acute aortic dissection.

BACKGROUND: Postoperative respiratory failure is often encountered in patients suffering from acute aortic dissection (AAD) and is believed to be influenced by release of neutrophil elastase after cardiopulmonary bypass. Sivelestat is a specific neutrophil elastase inhibitor, and this study aims to evaluate the effects of sivelestat on postoperative respiratory failure due to AAD. METHODS AND RESULTS: Patients who were operated for AAD from January 2000 to April 2005 and who had less than 300 mmHg initial postoperative PaO (2)/FiO (2) were investigated retrospectively and divided into two groups. Group 1 (n = 9) received intravenous administration of sivelestat immediately after the operation, while Group II (n = 9) received no sivelestat. There were no significant differences between Group I and II with respect to patients' characteristics or background (age, body weight, operating time, cardiopulmonary bypass time, amount of bleeding, preoperative WBC number and initial PaO (2)/FiO (2)). Though patients in Group I showed a subtle improvement in certain parameters such as PaO (2)/FiO (2), A-aDO (2) and respiratory index (RI) over a 3-day observation period compared to those of Group II, there were no significant differences. Neither postoperative mechanical ventilation time nor ICU stay differed between Group I and II. However, Group I showed a significantly greater improvement in the ratio of RI to initial RI on the 3POD compared to that of Group II (61.6 +/- 44.2 % vs. 111.9 +/- 40.9 %, P = 0.02). CONCLUSION: Inhibiting the activity of the neutrophil elastase may attenuate the postoperative respiratory complications of patients with AAD.

Acute Disease↗

PubMed2006

[Tracheobronchial injury].

We studied 6 cases of tracheobronchial injury due to the blunt chest truma in our department. All patients were male of 19 to 60 years of age. Injured sites were main bronchus in 2, tracheobronchial portion in 2, cervical trachea and main bronchus in 1, cervical trachea in 1. In a case of cervical tracheal injury and 2 cases of tracheobronchial injury, emergent operation was performed on the day of accident. Other cases with the main bronchial injury underwent conservative treatment at first, but subsequent bronchoplasty was necessary for them due to the bronchial stenosis. After the surgery for 2 cases of tracheobronchial injury, mechanical ventilation with double lumen tube was continued to reduce the airway pressure for the anastomotic sites. In conclusion, early surgical treatment is recommended for the airway injury and the respiratory management using double lumen tube after surgery may be helpful in preventing trouble at the anastomosis.

Adult↗

PubMed2003

Effects of pulmonary artery remodeling on pulmonary circulation after lung volume reduction surgery.

BACKGROUND: Significant pulmonary hypertension during exercise has been observed in patients with severe chronic obstructive pulmonary disease. Although favorable effects on pulmonary function and dyspnea symptoms have been demonstrated, the influence of lung volume reduction surgery (LVRS) on the pulmonary hypertension during exercise is still a controversial subject. METHODS: A pulmonary function test and 6-minute walking test were performed before and 3, 6, 12 and 24 months after LVRS (n = 12). Pulmonary hemodynamics at rest and during exercise was studied 6 months after operation. Morphology was examined in pulmonary arteries with external diameters of 100 - 200 micro m in the resected lung, and the wall thickness (defined as intima plus media) and percentage wall thickness (percentage wall thickness of the external diameter) of the pulmonary artery were calculated. RESULTS: LVRS improved early-phase pulmonary function and 6-minute walking distance. Although the increase in pulmonary capillary wedge pressure during exercise was significantly ameliorated, exercise pulmonary hypertension did not change after LVRS. The percent wall thickness was highly correlated with Delta Ppa (difference between mean pulmonary artery pressure at rest and mean pulmonary artery pressure during exercise) not only before, but also 6 months after LVRS. CONCLUSION: LVRS has no significant influence on exercise-induced pulmonary hypertension in patients with severe emphysema. From a histological analysis of the pulmonary artery in the resected lung, remodeling the pulmonary artery that may exist in the remaining lung is possibly one of the important factors preventing postoperative improvement in exercise pulmonary hypertension in patients with chronic obstructive pulmonary disease.

Aged↗

PubMed2002

Differences and relationships of thymidine phosphorylase expression in tumor-associated macrophages and cancer cells in squamous cell carcinoma of the esophagus.

Thymidine phosphorylase (TP), which has been shown to be identical to platelet-derived endothelial cell growth factor, is expressed in tumor-associated macrophages (TAMs) as well as cancer cells. The aim of this study was to clarify the differences or relationships of TP expression in TAMs and cancer cells in esophageal squamous cell carcinoma (SCC). Tissues samples were taken from 56 patients with esophageal SCC after curative surgery. The expression of TP in TAMs or SCC cells was examined using a monoclonal antibody to TP (clone 654-1). Microvessels in SCC that stained positively for Factor VIII-related antigen were counted (microvessel density, MVD). Macrophages in SCC that stained positively for CD68 antigen were counted (monocytic count). Ki-67 antigen was immunostained with MIB-1, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick end labeling was performed, and Ki-67 labeling index (LI) and apoptotic index were calculated. The expression of TP in stromal cells and cancer cells was observed in 43 (76.8%) and 33 patients (58.9%), respectively. There were significant correlations between TP expression in stromal cells (TAMs) as well as in cancer cells and venous invasion, distant metastasis, or MVD. There was a correlation between TP expression in cancer cells and lymph node metastasis, and there were correlations between TP expression in TAMs and monocytic count or Ki-67 LI; however, there was no correlation between TP expression in TAMs and lymph node metastasis. On the other hand, in SCCs with TP expression in both TAMs and cancer cells, higher frequencies of venous invasion and distant metastasis, higher MVD and lower apoptotic index were observed than in other SCCs. The 5-year survival rate in patients with TP expression in both TAMs and cancer cells was poorer than that in patients with TP expression in neither TAMs and cancer cell. In conclusion, these results suggest that co-expression of TP in TAMs and cancer cells is strongly associated with angiogenic promotion and distant metastasis. However, other effects of TP, such as promotion of tumor growth and lymph node metastasis, may be different depending on whether these are expressed in TAMs or cancer cells in esophageal SCCs. Patients with coexpression of TP in TAMs and cancer cells may be associated with a poor prognosis.

Antigens, CD↗

PubMed2002

Can sedation reduce the cardiac stress during gastrointestinal endoscopy? A study with non-invasive automated cardiac flow measurement by color Doppler echocardiography.

BACKGROUND: Upper gastrointestinal endoscopy (UGIE) may cause some cardiac stress. The effect of sedation on hemodynamics during UGIE has not been fully studied, and therefore the aim of this study was to clarify whether or not sedation can reduce cardiac stress dufing UGIE. METHODS: Eight normal male volunteers undergoing UGIE with sedation (0.1 mg/kg of midazolam) and without it (two endoscopies per volunteer in random order) were monitored throughout the procedure by means of electrocardiogram, blood pressure and peripheral oxygen saturation (SpO2). Cardiac output was measured at six points before, during and after endoscopy from automated cardiac flow measurement by color Doppler echocardiography. Serum norepinephrine, epinephrine, dopamine and ACTH concentrations were measured before and after the examination. RESULTS: No significant differences in heart rate, systolic blood pressure, rate-pressure product, cardiac output and left ventricular work index were observed between the sedated and non-sedated groups. SpO2 hardly changed during endoscopy in the non-sedated group, but decreased slightly in the sedated group (P = 0.075). Although all serum catecholamine concentration changes were within normal limits in both groups, after endoscopy only epinephrine concentration was significantly lower in the sedated group than in the non-sedated group (P = 0.0027). CONCLUSIONS: Conscious sedation with midazolam does not reduce the cardiac stress during UGIE.

Adrenocorticotropic Hormone↗

PubMed2002

Expression of basic fibroblast growth factor and its receptor-1 in cardiac myxoma.

BACKGROUND: To clarify the significance of basic fibroblast growth factor (bFGF) in angiogenesis or proliferative activity in cardiac myxoma, the expression of bFGF and its receptor (FGFR-1) were immunohistochemically examined. METHODS: Formalin-embedded tissues of cardiac myxomas were obtained by surgical resection from 15 patients and analyzed by immunostaining of bFGF and FGFR-1. The microvessel density was measured in the 15 myxomas using platelet derived endothelial cell adhesion molecule-1. For evaluation of proliferative activity of the cardiac myxomas, proliferating cell nuclear antigen (PCNA) immunostaining was performed, and the PCNA labeling index was measured in each section. RESULTS: bFGF and FGFR-1 were observed in 73.3% and 67.7% of the myxomas, respectively. There was a close correlation between the expression of bFGF and FGFR-1. This co-expression was frequently observed in the myxoma cells around the microvessels appearing as a ring structure. Regarding possible relationships between the expression of bFGF or FGFR-1 and the clinicopathologic features, there were no parameters excluding the macroscopic type of myxoma. The microvessel density in the myxomas with bFGF or FGFR-1 expression was higher than that in myxomas without it. The PCNA labeling index in myxomas with bFGF expression was higher than that in myxomas without it, and the PCNA labeling index tended to be higher in myxomas with FGFR-1 expression than that in myxomas without it. CONCLUSIONS: bFGF and/or FGFR-1 was expressed in some of cardiac myxoma, and may be an important role for tumor angiogenesis and proliferative activity.

Aged↗

PubMed2002

[Minimally invasive direct coronary artery bypass in a patient with idiopathic thrombocytopenic purpura; report of a reoperative case].

A 77-year-old man who had undergone coronary artery bypass grafting (CABG) to segment 3, 7 and 12-14 with saphenous vein grafts (SVG) 15 years before, and ligation of coronary arteriovenous (AV) fistula 8 years before was admitted to our hospital, and diagnosed as acute heart failure and idiopathic thrombocytopenic purpura. Coronary angiography showed multiple stenosis of three vessels, and the grafts to segment 3 and 7 were occluded. The area of left anterior descending (LAD) had no viability, but the inferior wall had viability on dobutamine load echocardiography. The platelet count was about 5.0 x 10(4)/mm3. Minimally invasive direct coronary artery bypass (MIDCAB) for right coronary artery (RCA) using right internal thoracic artery (RITA) was performed through right parasternotomy. Operative and postoperative bleeding was slight, and postoperative course was uneventful. Reoperative MIDCAB can be safely performed in a patient with idiopathic thrombocytopenic purpura, and should be considered a viable alternative for highrisk patients.

Aged↗

PubMed2001

Comparative study of glycosyltransferase activities in Caco-2 cells before and after enterocytic differentiation using lectin-affinity high-performance liquid chromatography.

Human colonic adenocarcinoma Caco-2 cells differentiate into enterocytes by induction with sodium butyrate after confluence. Our previous studies have shown that there are high levels of H type 1 blood group antigen and core 2 structure present in O-glycans of the glycoproteins from these differentiated cells and these O-glycans appear to be indispensable for the process of differentiation of the cells (J. Amano and M. Oshima, 1999, J. Biol. Chem. 274, 21209-21216). Here, we have determined the glycosyltransferase activities using lectin-affinity HPLC because the method enabled easy separation and identification of mixtures of isomeric oligosaccharide structures due to the high resolution and reproducibility. The activities of beta 3-galactosyltransferase, alpha 2-fucosyltransferase, which are responsible for H type 1 antigen biosynthesis, and core 2 beta 6-N-acetylglucosaminyltransferase in differentiated Caco-2 cells were higher than those in undifferentiated cells. These results demonstrate that an increase in specific glycosyltransferase activities brought on a change of the O-glycan structures during differentiation.

Animals↗

PubMed2001

Macroscopic extranodal invasion is a risk factor for tumor recurrence in papillary thyroid cancer.

Papillary thyroid cancer patients, upon whom curative operation was performed, were investigated to clarify whether or not macroscopic extranodal invasion is a risk factor for recurrence. They were divided into three groups: group A, patients whose primary tumor showed extrathyroidal invasion (n=31); group B, those whose metastatic lymph nodes showed extranodal invasion (n=6); group C, those who showed both extrathyroidal and extranodal invasion (n=9). Recurrence was significantly higher in groups B and C than in group A (P<0.05). It was concluded that macroscopic extranodal invasion to the adjacent structures was a risk factor for recurrence in patients with papillary thyroid cancer.

Adult↗

PubMed2001

Clinicopathological significance of core 2 beta1,6-N-acetylglucosaminyltransferase messenger RNA expressed in the pulmonary adenocarcinoma determined by in situ hybridization.

Cell surface carbohydrates of epithelial cells play important roles in tumor progression. Previously, we have shown that expression of core 2 branched O-glycans in colorectal cancer is closely correlated with the vessel invasion and depth of invasion (K. Shimodaira et al., Cancer Res., 57: 5201-5206, 1997). To test whether this is also the case in human lung cancer, we have examined the expression pattern of core 2 beta1,6-N-acetylglucosaminyltransferase (C2GnT) mRNA responsible for the biosynthesis of core 2 branched O-glycans in 41 cases of lung cancer. Using in situ hybridization, C2GnT mRNA was detected in 73.2% of the lung cancer cells, irrespective of the histopathological type; whereas in normal lung tissues, its expression was restricted to the basal cells of bronchial mucosa. These results indicate that the expression level of C2GnT mRNA was significantly enhanced in association with malignant transformation. Statistical analysis between the C2GnT mRNA expressed in pulmonary adenocarcinoma and clinicopathological variables revealed that the expression of C2GnT was correlated with vessel invasion and lymph node metastasis with significant difference (P < 0.05), but expression of sialyl Le(x), which is frequently expressed in the adenocarcinoma, was not significantly correlated with lymph node metastasis. These results indicate that C2GnT mRNA detected by in situ hybridization reflects the malignant potentials of pulmonary adenocarcinoma, because lymph node metastasis is the most affecting factor to the patients' prognosis.

Adenocarcinoma↗

PubMed2001

Recurrence of thymoma: clinicopathological features, re-operation, and outcome.

BACKGROUND: Even after complete resection, recurrence of thymoma is not infrequently observed, and treatment of recurrent thymoma remains controversial. STUDY DESIGN: One hundred and twenty-six patients underwent surgically complete resection for thymoma, and 24 of them had a recurrence. Surgical treatment of recurrent thymoma was attempted in 15 patients for a total of 18 times. In the present study, the relevance of clinicopathological features and the re-operation on the survival rate after the recurrence were determined. RESULTS: The most frequent recurrent type was pleural dissemination (92%), with local recurrence observed in 5%. Overall 5- and 10-year survivals after recurrence were 37 and 16%, respectively. Disease-free interval after initial operation and complication of myasthenia gravis had no significant effect on postrecurrent survival. The use of postoperative mediastinal irradiation had no effect on reducing the recurrence rate or improving survival after recurrence. Two of 15 patients who underwent re-operation died of major complications after It. pleuropneumonectomy for severe pleural dissemination. In the present study, the re-operation was not significantly effective for prolongation of postrecurrence survival. CONCLUSION: Our study showed that re-operation should not be attempted for all patients with recurrent thymoma. Because effect of subtotal resection for severe pleural recurrence is disappointing, total resection for minimal pleural dissemination or small local recurrence will be undertaken to improve postrecurrent survival. Careful follow-up for > 10 years will increase the chance of the total resection of the recurrent thymoma.

Adolescent↗

PubMed2001

Coronary arteriovenous fistula with annuloaortic ectasia and aortic regurgitation.

Cardiac catheterization in a 57-year-old man disclosed a left coronary artery-coronary sinus fistula with annuloaortic ectasia and severe aortic regurgitation. During surgery, the fistula vessel was exposed and clamped before infusing cardioplegic solution for cardiac arrest. The proximal orifice of the fistula was closed directly and the distal orifice doubly ligated. A modified Bentall's procedure was conducted without difficulty. The postoperative course was uneventful.

Aortic Valve Insufficiency↗

PubMed2001

Mitral stenosis and regurgitation with systemic lupus erythematosus and antiphospholipid antibody syndrome.

Cases of valvular disease accompanied by systemic lupus erythematosus and antiphospholipid antibody syndrome are uncommon. Here, we present a surgical case of mitral stenosis and regurgitation with systemic lupus erythematosus and antiphospholipid antibody syndrome. Mitral valve replacement was performed, and the postoperative course was uneventful. Pathohistological findings of the mitral valve showed degenerative change due to chronic inflammation, proliferative fibrous change and calcification without thrombus formation.

Antiphospholipid Syndrome↗

PubMed2001

A squamous cell carcinoma of the gastric cardia showing submucosal progression.

We report a case of squamous cell carcinoma (SCC) of the gastric cardia showing submucosal progression with direct invasion of the liver. A 71-year-old man was admitted with dysphagia. Esophagogastroscopy showed a protruding tumor covered with normal gastric mucosa in the anterior wall of the gastric cardia, although no abnormal findings were detected in the esophagus, including the esophagogastric junction. Serum SCC-related antigen level was elevated (6.6 ng/ml; normal level, less than 2.5 ng/ml). Endoscopic biopsy specimens taken from this tumor did not show malignant cells. Based on these findings, the preoperative diagnosis was a submucosal tumor of the stomach. Laparotomy was done; however, the tumor was not resected because it had direct invasion to the left lateral segment of the liver and adjacent tissues. As the tumor showed continuous bleeding from the stomach after surgery, total gastrectomy, combined with transhiatal lower esophagectomy, left lateral segmentectomy of the liver, splenectomy, and distal pancreatectomy was performed. Because histologic findings showed poorly or moderately differentiated SCC with direct invasion of the liver, the final diagnosis was SCC of the gastric cardia showing submucosal progression with hepatic invasion. Such a case of SCC of the gastric cardia showing submucosal progression is rare, and accurate preoperative diagnosis was very difficult. However, it may be important to consider SCC of the gastric cardia in such a situation.

Aged↗

PubMed2001

Hepatic resection for large hepatocellular carcinoma.

BACKGROUND: Long-term survival and prognostic factors after hepatic resection for large hepatocellular carcinoma (HCC) remain to be proved. METHODS: The surgical outcome in 133 consecutive patients with HCC in diameter of > or = 5 cm (large HCC; L group) undergoing hepatic resection was retrospectively clarified and compared with that of 253 patients with HCC in diameter of < 5 cm (small HCC; S group). Postresection prognostic factors were evaluated by univariate and multivariate analysis using Cox's proportional hazards model. RESULTS: The disease-free 3- and 5-year survival rates between L group and S group were 26% versus 42% and 20% versus 25%, respectively (P = 0.0032). The overall 3- and 5-year survival rates between L group and S group were 38% versus 67% and 28% versus 47%, respectively (P < 0.0001). Multivariate analysis revealed that large amount of intraoperative blood transfusion was an independently significant factor of poor disease-free and overall survivals. CONCLUSIONS: Long-term survival in patients with large HCC remains unsatisfactory compared with that in patients with non-large HCC. Restriction of intraoperative blood transfusion may play an important role in the improvement of survival and recurrence in such patients.

Blood Loss, Surgical↗

PubMed2001

Early growth-response factor 1 and basic transcriptional element-binding protein 2 expression in cardiac allografts.

Early growth-response factor 1 (Egr-1) and basic transcriptional element-binding protein 2 (BTEB2) are transcriptional factors that regulate multiple genes involved in phenotypic changes of smooth muscle cells (SMCs), one of the outstanding pathologic features of chronic cardiac allograft rejection. In this study, we used a heterotopic abdominal heart transplant model in monkeys to evaluate the roles of these molecules in graft coronary vasculopathy. We demonstrated that Egr-1 and BTEB2 are induced in vascular SMCs of rejected cardiac allografts well before morphologic changes, such as intimal thickening. These findings suggest that expression of Egr-1 and BTEB2 is one of the initial events in allograft angiopathy.

Animals↗

PubMed2001

Hepatic resection for hepatocellular carcinoma in the elderly.

BACKGROUND: Although the number of elderly people undergoing surgery for hepatocellular carcinoma (HCC) has increased because of the prolonged life expectancy rate, potential benefits of hepatectomy for elderly patients with HCC have not been fully delineated. STUDY DESIGN: Using medical records, surgical outcomes of HCC in 103 patients 70 years of age or older undergoing hepatic resection (older group) were clarified and compared with those of 283 patients younger than 70 years of age (younger group) in this retrospective study. Postresection prognostic factors were evaluated by multivariate analysis using Cox's proportional hazards model. RESULTS: There were no significant differences in postoperative complication, operative mortality, and overall hospital death rates between the two groups. Overall 3- and 5-year survival rates for the older group and the younger group were 51.0% versus 55.2%, and 42.2% versus 40.0%, respectively (p = 0.95). Disease-free 3- and 5-year survival rates for the older group and the younger group were 35.2% versus 37.6%, and 16.6% versus 24.2%, respectively (p = 0.66). Multivariate analysis revealed that the presence of liver cirrhosis and vascular invasion were independently significant factors of poor overall survival. CONCLUSIONS: Selected elderly patients with HCC benefited from resection as much as young patients, and age by itself may not be a contraindication to surgery. Postresection longterm prognosis in the elderly was determined by the presence of liver cirrhosis and vascular invasion.

Adult↗

PubMed2001

Intestinal epithelial cells express and secrete the CD43 glycoform that contains core 2 O-glycans.

Several glycoforms of CD43 are known to regulate cellular interactions in the immune system. One such glycoform, the CD43 that bears core 2 O-glycans, is also known to be expressed on T lymphocytes and natural killer cells, but only after their activation. Previous studies have also shown that when Caco-2 cells, which are derived from human colon carcinoma, differentiate into enterocytes, they also express core 2 O-glycans, though proteins bearing this glycan are unknown. To examine whether CD43 glycosylation is altered during enterocytic differentiation of Caco-2 cells, we conducted immunocytochemical studies with a monoclonal antibody, 1D4, that recognizes a glycoform of CD43 bearing core 2 O-glycans. We found that 1D4 could bind to intracellular granules but not the cell surface of differentiated Caco-2 cells, whereas hematopoietic cells expressed 1D4 epitope on the cell surface as previously shown. The reactivity with this antibody increased as the degree of cell differentiation progressed as shown by the activity of the apical enzyme marker, dipeptidyl peptidase IV. 1D4-reactive CD43 was also found in the culture medium of differentiated Caco-2 cells, suggesting this molecule may be stored and secreted. The production and secretion of this CD43 glycoform by enterocyte-like Caco-2 cells was enhanced, and most 1D4 epitope converted to a soluble form when bacterial lipopolysaccharide was present. These observations strongly support the possibility that core 2 O-glycans on mucins such as CD43 are important to primary defense on the intestinal epithelium against infection.

Antigens, CD↗