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T Asakura

Publications and source records attributed to T Asakura.

At least 91 records · Page 5Linked to original sources
PubMed1998

[Coronary artery bypass grafting in cases with poor left ventricular function].

From January 1987 through June 1992, 18 patients with poor left ventricular function (left ventricular ejection fraction [LVEF] less than 0.3) underwent elective isolated primary coronary artery bypass surgery. The mean age was 56.4 years (range, 46 to 72 years), and 15 were males and 3 were females. Mean pre-operative LVEF measured by ventriculography was 0.26 +/- 0.03 (range, 0.19 to 0.30). Sixteen patients (88.9%) had a prior myocardial infarction and 9 (50%) had a history of congestive heart failure. Complete revascularization was the goal for all patients, and the mean number of bypass grafts was 3.0 +/- 0.8 per patient. The left anterior descending coronary artery (LAD) was revascularized in all patients. There were no operative deaths. Post-operative LVEF improved significantly from 0.26 +/- 0.03 to 0.42 +/- 0.11 (p = 0.0002), and the regional left ventricular wall motion improved in the diaphragmatic and posterobasal regions (p < 0.01). The patency of the grafts was 93.9% in all, and 100% for LAD. The mean follow-up period was 77 months, and the overall actuarial survival rate was 88.9% at 10 years. During follow-up periods, two patients died of congestive heart failure (CHF), and two required three rehospitalizations because of CHF. The overall cardiac event free rate was 75.8% at 10 years. In patients with poor left ventricular function, surgical revascularization can be performed safely, but congestive heart failure sometimes occurs during follow-up periods and may be the cause of death. Therefore alternate forms of therapy such as cardiac transplantation and/or TMLR should be considered in selected patients.

Aged↗
PubMed1998

Duodenal gastrinoma--clinical features and usefulness of selective arterial secretin injection test.

Duodenal gastrinoma is recognized as a relatively common cause of Zollinger-Ellison syndrome, but its clinical and biological features are not well known. Here we report a case of duodenal gastrinoma with lymph node metastasis which was confirmed by pathology examinations. Hypergastrinemia and gastric acid hypersecretion were documented, but the secretin test showed negative results. An enlarged peripancreatic lymph node lying close to the pancreas head was the only positive finding on preoperative imaging studies. The results of the selective arterial secretin injection (SASI) test suggested that the primary tumor was located in the gastrinoma triangle. Finally, surgical exploration was carried out and a submucosal tumor, approximately 15 mm in size, was detected by intraoperative palpation at the posterior wall of the proximal portion of the duodenum. Intraoperative pathology examination demonstrated metastases to regional lymph nodes. The present case calls attention to the unique features of duodenal gastrinomas, which differ from those of pancreatic origin: a highly malignant potential for its small size, and submucosal location in the proximal duodenum. The SASI test is recommended for assessing the location of a primary lesion if it cannot be identified by various conventional imaging studies.

Diagnosis, Differential↗
PubMed1998

Cyclin D1 protein overexpression is related to tumor differentiation, but not to tumor progression or proliferative activity, in transitional cell carcinoma of the bladder.

PURPOSE: We attempted to clarify the significance of cyclin D1 in the development and progression of transitional cell carcinoma of the bladder in humans. MATERIALS AND METHODS: Immunohistochemical staining of archival tissue specimens of transitional cell bladder carcinoma obtained from 163 patients was performed by the labeled streptavidin-biotin-peroxidase method. RESULTS: Cyclin D1 protein overexpression was observed in 51 of the 163 specimens (31.3%). Cyclin D1 protein overexpression was showed a highly significant inverse correlation with the histological grade of malignancy (p < 0.01). Grade 3 tumors showed a highly significant low incidence of cyclin D1 protein overexpression as compared with grade 2 tumors (p < 0.01). There was no significant correlation between the overexpression of cyclin D1 protein and tumor stage or the Ki-67 labeling index. CONCLUSION: Cyclin D1 in transitional cell bladder carcinoma was closely related to tumor differentiation but not to tumor progression. Transitional cell carcinoma of the bladder may utilize another pathway for proliferation that is independent of cyclin D1.

Carcinoma, Transitional Cell↗
PubMed1998

Tomosyn: a syntaxin-1-binding protein that forms a novel complex in the neurotransmitter release process.

Syntaxin-1 is a component of the synaptic vesicle docking and/or membrane fusion soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) complex (7S and 20S complexes) in nerve terminals. Syntaxin-1 also forms a heterodimer with Munc18/n-Sec1/rbSec1 in a complex that is distinct from the 7S and 20S complexes. In this report, we identify a novel syntaxin-1-binding protein, tomosyn, that is capable of dissociating Munc18 from syntaxin-1 and forming a novel 10S complex with syntaxin-1, soluble N-etyhlmaleimide-sensitive factor attachment (SNAP) 25, and synaptotagmin. The 130 kDa isoform of tomosyn is specifically expressed in brain, where its distribution partly overlaps with that of syntaxin-1 in nerve terminals. High level expression of either syntaxin-1 or tomosyn results in a specific reduction in Ca2+-dependent exocytosis from PC12 cells. These results suggest that tomosyn is an important component in the neurotransmitter release process where it may stimulate SNARE complex formation.

Animals↗
PubMed1998

Prognostic significance of Ki-67, p53, and Bcl-2 expression in prostate cancer patients with lymph node metastases: a retrospective immunohistochemical analysis.

The prognostic significance of Ki-67, p53, and Bcl-2 expression was evaluated in prostate cancer patients with lymph node metastases. Immunohistochemical staining of archived material obtained from 56 patients was performed by the streptavidin-biotin method. Univariate survival analysis showed that a Ki-67 labeling index (Ki-67 LI) of > or = 8.4 in the primary tumor identified a group of patients with a significantly poorer prognosis (P < 0.001). furthermore, a Ki-67 LI of > or = 8.7 in the nodal metastatic tumor was also associated with a poorer prognosis (P < 0.01). Multivariate analysis showed that the Ki-67 LI of primary tumors (P < 0.01) and lymph node metastases (P < 0.01) had independent prognostic value. p53 and Bcl-2 expression had no prognostic value in patients with prostate cancer and lymph node involvement. The Ki-67 LI has more prognostic value than p53 and Bcl-2 expression for patients with prostate cancer that has spread to the lymph nodes.

Aged↗
PubMed1998

Effect of an allosteric modifier of hemoglobin, RSR-4, on oxygen affinity and oxygen saturation of hemoglobin in rabbits.

Theoretically, if the arterial partial oxygen pressure (PaO2) does not change, a right shift in the oxygen equilibrium curve (OEC) of hemoglobin should reduce arterial oxygen saturation. In this study we investigate whether a right shift in the OEC of hemoglobin decreases transcutaneous oxygen saturation (Tc-SO2) following the administration of an allosteric effector, 2-[4-(((3, 5-dichloroanilino)-carbonyl) methyl) phenoxy]-2-methylpropionic acid (RSR-4). The effect of RSR-4 on hemoglobin oxygen affinity was studied in four New Zealand white male rabbits. Following intraperitoneal administration of RSR-4, Tc-SO2 decreased in a dose-dependent manner. P50 (partial oxygen pressure at 50% hemoglobin oxygen saturation) in whole blood increased as the concentration of RSR-4 increased. Tc-SO2 decreased as whole-blood affinity (1/P50) decreased. There was no positive correlation between Tc-SO2 and PaO2. We concluded that a decrease in hemoglobin oxygen affinity following RSR-4 administration reduced arterial oxygen saturation. This decrease in the presence of an allosteric effector such as RSR-4 in vivo can be detected and monitored as a reduction in Tc-SO2.

Aniline Compounds↗
PubMed1998

[Prognosis in the cases with renal cell carcinoma according to clinical parameters].

BACKGROUND: The objects of this study is to evaluate the clinical prognostic factors in renal cell carcinoma. MATERIALS AND METHODS: During a 30-year period from January 1965 to December 1994, 1301 cases with renal cell carcinoma were treated at the Yokohama City University Hospital and its affiliated hospitals. In these cases, cause specific 679 cases from January 1965 to December 1990 were analyzed in a study undertaken to investigate long-term treatment results and clinical prognostic factors. RESULTS: 1. The cause specific 5-, 10-, 15-, and 20-year survival rates were 48.7%, 41.1%, 32.3%, and 26.5% respectively, indicating thus that a great number of cases had an ominous prognosis even 5 years or moreafter surgical treatment. 2. Among patients under 40 years of age (n = 29) none died more than 2 years after receiving operation, the prognosis for this particular group of cases being relatively good. 3. Female, incidentally detected cancer, small tumor size (< or = 4.0 cm), slow growing type and low stage were proven to be favourable prognostic factors in renal cell carcinoma. 4. The cause specific 5-year survival rate for the patients (n = 239) from 1965 to 1981 was 33.8%, while the rate for the patients (n = 440) from 1982 to 1990 was 56.5%. This improvement of survival rate was brought by the increase of the incidentally detected renal cell carcinoma. 5. In the incidentally detected renal cell carcinoma, the incidence of slow growing cases and the cases of less than 4.0 cm tumor size were higher than in the symptomatic renal cell carcinoma. 6. Multivariate analysis using Cox's proportional hazard model showed that stage was the most important prognostic factor. CONCLUSIONS: These results suggested that sex, age, symptom, tumor size, growing type, and stage were important prognostic factors in renal cell carcinoma.

Adolescent↗
PubMed1998

[Clinicopathological study on patients with renal cell carcinoma according to whole area histological sections].

BACKGROUND: We tried to establish new classification of histological grade and indication of elective nephron-sparing surgery (ENSS) in renal cell carcinoma (RCC), and studied histological changes according to tumor size. METHODS: We made whole area histological sections on 142 cases with RCC and investigated histological aspects and prognosis. RESULTS: (1) To classify the grade of the cases, the worst grade which occupied more than 10% of the tumor provided most appropriate prognosis. (2) In 144 cases (kidneys), satellite tumor lesions (STL) were observed in 69 cases (47.9%), and the cases with vein invasion were observed in 75 cases (51.4%). Incidence of these two factors increased with tumor size. (3) From the point of view of location of STL and vein invasion, ENSS was possible with taking more than 2 cm surgical margin in the cases with less than 4 cm in size and slow growing type. But indication of ENSS should not be decided with ease. (4) Incidence of the cases with multiple structural and cell types and grades increased with tumor size. (5) Incidence of the cases with solid structure, spindle or pleomorphic cell type and high grade increased with tumor size. (6) It was supposed that tumor heterogeneity and progression could be associated with tumor growth in each cases. CONCLUSION: These results suggest the necessity of treatment of the cases with RCC as small as possible. If the tumor is less than 4 cm, prognosis tends to be good, and ENSS might be possible in some cases.

Carcinoma, Renal Cell↗
PubMed1998

[Successful removal of a giant ball thrombus in the left atrium in an aged patient with unusual course].

A case of left atrial ball thrombus associated with severe mitral stenosis was reported. This male patient, aged 78, came in the chief complaint of leg and facial edema. An echocardiographic examination revealed the presence of mitral stenosis and floating giant ball thrombus in the atrium. He suffered from acute thromboembolism in his right leg six years ago and had been treated with anticoagulant since then. Despite this a floating giant ball thrombus was observed. Emergency operation including mitral valve replacement and thrombectomy was successfully performed. Thrombus formation in the left atrium is not uncommon but it is very rare to encounter in patients receiving anticoagulant therapy. To manage these patients well, meticulous attention must be paid during induction of anesthesia, intra-operative procedures, perioperative care, and operative position.

Aged↗
PubMed1998

[Outcome of emergency surgery for Stanford type A aneurysms: selection of operative procedures and supported systems of cerebral protection].

Fourteen surgical cases of acute dissecting aneurysms of Stanford type A were reported. Clinical symptoms, operative methods, pathophysiology, cerebral protection, supported systems, and prognosis were examined. All patients underwent surgery within 5 days of symptom onset. The patient population consisted 8 males and 6 females with a mean age of 56.6 years. Ascending aortic replacement was performed using a vascular graft 12 patients. ECC was performed under deep hypothermia. Femoral artery cannulation and retrograde cerebral perfusions was performed in all cases. The ascending aorta was the site of entry in 13 of the 14 cases. Whenever feasible, enhanced CT and aortography were performed to confirm the entry lesion. Two patients expired. One patient died intraoperatively due to massive bleeding. The other patient, while hospitalized, experienced a cerebrovascular accident and died due to pneumonia. All other patients ran an uneventful post-operative course without cerebrovascular accident. In conclusion we think that although ascending aorta replacement using prosthetic grafts is not ideal for patients with Stanford type A dissecting aneurysms, it is a viable option for emergency cases. We found retrograde circulatory cerebroplegia (RCCP) to be satisfactory for brain protection during these emergency procedures.

Adult↗
PubMed1998

Polymorphism of feline beta-globins studied by reversed-phase high-performance liquid chromatography.

OBJECTIVE: To characterize the feline beta-globin system with respect to the number and genetics of adult beta-globin chains. ANIMALS: 84 domestic and purebred cats (9 breeds), 14 cats were mildly to severely anemic. For genetic analyses, 12 litters with 1 to 5 offspring for a total of 29 kittens. PROCEDURE: Feline globins from erythrocyte lysates were separated by reversed-phase high-performance liquid chromatography and analyzed on the basis of retention time and area of each beta-globin peak. Mixing studies with half the amount of hemoglobin (Hb) from 2 cats were performed to assign the beta-globin peaks in each cat. The Hb from 60 cats were also separated by standard isoelectric focusing methods. RESULTS: Heme and alpha- and beta-globins were effectively separated by high-performance liquid chromatography. Although there was only 1 alpha-globin, a total of 6 beta-globins (I through VI) were identified, with each cat having 1 to 4 beta-globin chains. From analysis of the number of beta-globins, their relative amounts, and Hb mixing studies, 17 beta-globin patterns were observed. The beta-globin pattern in healthy and anemic cats was identical. Family studies documented an autosomal codominant mode of inheritance of the adult beta-globins and a linkage of 2 beta-chains forming haplotypes. CONCLUSIONS: Biochemical and genetic evidence for the greatest polymorphism of adult beta-globins thus far described in any species is provided. A feline beta-globin gene region with 2 linked beta-globin gene loci and 2 and 5 alleles is proposed. CLINICAL RELEVANCE: Better understanding of feline Hb will likely be helpful for diagnosis of hemoglobinopathies in anemic cats.

Alleles↗
PubMed1998

[The investigation of surgical procedures for post infarcted ventricular septal defects: a comparison between Daggett and David method].

Post infarcted ventricular septal perforations (VSP) has diverse clinical and pathological manifestations and the surgical results in severe cases have not yet been satisfactory. In the past we had performed the procedure of Daggett. However since 1992 we have also introduced the procedure of infarction exclusion technique proposed by David which involves plastering the ventricular cavity in a large patch without infarcted myotomy. We reported 5 cases treated with David method, 5 cases with Daggett method, and their results were compared. There were four mortality cases in Daggett method and three in David method. No significant difference was observed regarding the surgical mortality. However, there were different post-operative features between the two groups. In Daggett method patients had prolonged heart failure and LOS. In David method patients, had no severe LOS, but residual shunt were recognized in two cases. We think that the emergence of residual shunt in David method was probably due to suturing without prior removal of the damaged fragile infarcted myocardium. In Daggett method there were death cases caused by LOS and postoperative heart failure but without residual shunts. Despite its recent growing popularity for treating VSP, our experience suggests that residual shunt is an important issue remains to be solved in David method.

Aged↗