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T Manabe

Publications and source records attributed to T Manabe.

At least 37 records · Page 2Linked to original sources
PubMed2001

Reoperative coronary artery bypass grafting via a left thoracotomy and a small laparotomy without cardiopulmonary bypass: report of a case.

A 66-year-old woman with aortic stenosis underwent an aortic root replacement with a composite graft and coronary artery reconstruction 2 years before presentation. On coronary angiography performed 2 years after operation, saphenous vein graft (SVG) to right coronary artery and SVG to first diagonal branch had both become totally occluded. SVG to left anterior descending artery showed 75% stenosis on the heel side of the distal anastomosis. The patient underwent a second coronary artery bypass via a left thoracotomy (the left internal thoracic artery was anastomosed to the first diagonal branch by interposing it with the left radial artery) and a small laparotomy (the right gastroepiploic artery was anastomosed to the right coronary artery) without a cardiopulmonary bypass. This approach is preferable to avoiding both a resternotomy and cardiopulmonary bypass in patients requiring repeat surgery.

Aged↗
PubMed2001

A collision tumor composed of adenocarcinoma and malignant lymphoma in the remnant stomach after pancreatoduodenectomy: report of a case.

The occurrence of a collision tumor in the stomach, consisting of adenocarcinoma and malignant lymphoma, is extremely rare. We report herein the case of a patient who had undergone a pancreatoduodenectomy for bile duct cancer 5 year earlier, in whom an ulcerating tumor of the remnant stomach developed and grew rapidly within 5 months. Surgical exploration revealed a tumor in the remnant stomach, multiple liver metastases, and multiple lymph node metastases. Total resection of the remnant stomach was performed, and pathological examination revealed a collision tumor consisting of adenocarcinoma and malignant lymphoma. The patient died of liver metastases and lymph node metastases 7 months after his second operation. The coexistence of both adenocarcinoma and malignant lymphoma of the remnant stomach and the etiology of this unusual combination, never previously reported, is discussed.

Adenocarcinoma↗
PubMed2001

Intranodal benign thyroid tissue: significance of HBME-1 in differentiation from metastatic papillary thyroid carcinoma.

The aim of this study was to determine the significance of HBME-1 immunostaining in the differentiation between intranodal benign thyroid tissue and metastatic papillary thyroid carcinoma in the lymph node. Immunohistochemically we examined normal-appearing intranodal thyroid tissue in four patients who did not show evidence of papillary carcinoma histologically or clinically. We also examined follicular-pattern-predominant papillary carcinoma with metastatic foci in the lymph nodes. Normal-appearing intranodal thyroid tissue and normal thyroid showed no immunopositivity for HBME-1. In contrast, all papillary carcinomas in both the lymph nodes and thyroid demonstrated strong positivity for HBME-1. HBME-1 was predominantly positive for the luminal surface of the tumor cells. The immunopositivity of the cuboidal and low columnar carcinoma cells was more intensive than that of the flat-shaped cells in the lymph nodes and thyroid. The results probably indicate that HBME-1 immunostaining is helpful in distinguishing between intranodal benign thyroid tissue and metastatic papillary carcinoma in lymph nodes. We emphasize that the HBME-1 reactivity should be evaluated in connection with the histological findings, and that positive and negative controls stained in parallel are necessary.

Aged↗
PubMed2001

Enhancement of hippocampal LTP, reference memory and sensorimotor gating in mutant mice lacking a telencephalon-specific cell adhesion molecule.

Telencephalin (TLCN) is a cell adhesion molecule selectively expressed in the telencephalon of the mammalian brain. The mutant mice lacking TLCN had no detectable abnormalities in their neural development and synaptic structures. Ablation of TLCN increased the hippocampal long-term potentiation and its saturation level. The TLCN mutation selectively enhanced the performance of the radial maze and water-finding tasks, learning tasks with appetitive reinforcers, but not the contextual fear conditioning and Morris water maze tasks with aversive stimuli for conditioning. Furthermore, the TLCN mutant mice showed an increase of prepulse inhibition of the acoustic startle response. These results suggest that TLCN is a determinant of the dynamic range of synaptic plasticity and plays roles in reward-motivated learning and memory and sensorimotor gating.

Animals↗
PubMed2001

Requirement of appropriate glutamate concentrations in the synaptic cleft for hippocampal LTP induction.

Although glutamate transporters maintain low extracellular levels of the excitatory neurotransmitter glutamate in the nervous system, little is known about their roles in synaptic plasticity. Here, using knockout mice lacking GLT-1, that is the most abundant glial subtype of glutamate transporters, we showed that long-term potentiation (LTP) induced by tetanic stimulation in mutant mice was impaired in the hippocampal CA1 region. When tetanic stimulation was applied in the presence of low concentrations of an N-methyl-D-aspartate (NMDA) receptor antagonist, the impairment was overcome. Consistent with these results, the increased glutamate in the synaptic cleft of mutant mice preferentially activated NMDA receptors. Furthermore, analyses of mutant mice revealed that the magnitude of NMDA receptor-dependent transient synaptic potentiation during low-frequency stimulation depended on the concentration of glutamate in the synaptic cleft. These findings suggest that GLT-1 plays critical roles in LTP induction, as well as in short-term potentiation, through regulation of extracellular levels of glutamate, which enables appropriate NMDA receptor activation.

ATP-Binding Cassette Transporters↗
PubMed2001

Lobular endocervical glandular hyperplasia is a metaplastic process with a pyloric gland phenotype.

AIMS: Lobular endocervical glandular hyperplasia of the uterine cervix is a rare pseudoneoplastic lesion of the uterine cervix, described recently. Our aim was to characterize the clinicopathological and immunohistochemical features of lobular endocervical glandular hyperplasia, to elucidate its pyloric gland phenotype, and to distinguish it from adenoma malignum of the uterine cervix. METHODS AND RESULTS: Nine cases of lobular endocervical glandular hyperplasia were studied histologically and immunohistochemically. The average age of the nine patients was 48.8 years (range 38-64 years). Six cases were found incidentally, whereas in three cases a watery vaginal discharge and imaging studies suggested adenoma malignum preoperatively. Microscopically, lobular endocervical glandular hyperplasia ranged from 1 mm to 20 mm (mean 6.8 mm) in the largest horizontal extent and 1 mm to 10 mm (mean 3.9 mm) in depth, and was characterized by lobular arrangements of small glands composed of low columnar cells with pale eosinophilic cytoplasm and bland nuclei. Three cases showed a pseudo-invasive growth. Intracytoplasmic mucin was predominantly PAS-positive, and seven cases showed immunoreactivity for M-GGMC-1, an antibody that reacts with pyloric gland-type mucin. Only focal and faint reactivity for CEA was seen, and ER was negative in all cases. The cytokeratin profile was CK7+/20- in all cases, in keeping with their Müllerian derivation. All three lesions examined contained chromogranin-positive endocrine cells. After surgery all patients are well without recurrent disease (mean follow-up was 48.4 months). CONCLUSIONS: Lobular endocervical glandular hyperplasia is a morphologically distinct pseudoneoplastic glandular lesion, which has unique phenotypic characteristics shared by pyloric glands of the stomach. Although most are found incidentally, some cases may show clinical and radiological features resembling those of adenoma malignum.

Adenocarcinoma, Mucinous↗
PubMed2001

Secondary tumors of the pancreas: clinicopathological study of 103 autopsy cases of Japanese patients.

To investigate the clinicopathological features of patients with secondary tumors of the pancreas, we reviewed autopsy records and pathological features of 103 cases with pancreatic secondary tumors from 690 cases of malignant tumors (excluding cases of primary pancreatic cancer) over a 10-year period. There were 67 men and 36 women in the study, ranging in age from 2 to 94 years (mean: 61 years). The incidence of pancreatic secondary tumors was 15% in the autopsy cases of malignant tumors, and the majority of the secondary tumors were carcinomas. The stomach was the most common primary tumor site (20%), followed by the lung (18%) and extrahepatic bile duct (13%). Because the total number of each primary carcinoma differed, we paid specific attention to the incidence of pancreatic metastasis in each primary carcinoma. We found that carcinoma of the papilla of Vater showed the highest rate of incidence (75%) of pancreatic metastasis in each type of primary carcinoma. Approximately half of the metastatic lesions were solitary, but the metastatic lesions in the pancreas could not be identified macroscopically in 34 cases (33%). Histologically, the most common carcinoma was adenocarcinoma, followed by large cell carcinoma, small cell carcinoma and neuroendocrine carcinoma. The most common non-epithelial tumor was leukemia, followed by malignant lymphoma. Undifferentiated carcinoma and neuroendocrine carcinoma were often found in cases of extrahepatic bile duct or urinary bladder carcinoma with pancreatic metastasis. As for the microscopic infiltration patterns of tumor cells, 73% of cases showed an interlobular and intralobular infiltration. Fat necrosis was most frequently seen as an associated pathological finding (19%). Our study indicates that secondary tumors of the pancreas can be found in approximately one out of six to seven autopsy cases of malignant tumors, and in Japan, the most common of these is adenocarcinoma of the stomach.

Adolescent↗
PubMed2001

Midterm results of stent-graft repair for thoracic aortic aneurysms: computed tomographic evaluation.

Midterm observation of endovascular surgery using a fabric-covered stent graft for thoracic aortic aneurysms is discussed with postoperative follow-up findings based on regularly performed thoracic computed tomography (CT). From 1996 to 1999, 20 patients with thoracic aortic aneurysm underwent stent-graft placement in our hospital. One year follow-up CT results after placement were obtained for 17 patients. The CT scans found that there were both thrombosis and size reduction of aneurysm in 8 patients (46%), thrombosis without size reduction in 2 (13%), a new ulcerlike projection (ULP) in 3 (19%), persistent minor endoleakage in 2 (13%), a new endoleak in 1 (6%), and a recurrent endoleak from intercostal arteries in 1 (6%). The new ULP formation seemed to be a peculiar problem stemming from an intimal injury caused by edges of the stent. Therefore, we recently adopted a new spiral stent instead of the previous stent to avoid the injury. The new endoleak suggested that aneurysmal thrombosis without size reduction could cause the aneurysm to develop recurrent endoleaks. From these findings, we concluded that midterm observation of stent-graft repair for thoracic aortic aneurysms did not give satisfactory results. In order to improve the results of endovascular surgery using stent-grafts, we need to develop safer stent grafts with a reliable design to prevent endoleaks and to avoid intimal injury of the aorta. We also hope to develop effective technologies that can accelerate organization of thrombus in the aortic aneurysm after stent-graft placement.

Adult↗
PubMed2001

Introduction of tissue engineering concepts into the field of endovascular grafts: an attempt to solve endoleakage problems of endovascular grafts implanted in aortic aneurysms.

To solve endoleakage problems of endovascular prostheses inserted in aortic aneurysms, a concept originating from tissue engineering was proposed. We proposed that in order to accelerate the thrombus inside the aneurysm, three major factors for successful tissue engineering, i.e., appropriate cells, extracellular matrices, and growth factors, should be introduced into a space between the endovascular grafts and the aneurysm. As a simulation model in animals, two kinds of fabric vascular prostheses were used. One was a small graft used as an endovascular graft and another was a large graft as an envelope for the small graft, used as the aneurysm wall. Adipose tissue fragments with fresh blood coagula were injected between the two grafts. The control was a preparation without tissue fragments. Two months and a half after surgery, the test group showed complete connective tissue formation in the space between the two grafts, but in the control, brownish thrombus remained. From this experiment, we speculated that tissue fragment transplantation will accelerate connective tissue formation of the thrombus, and this complete organization of the thrombus might reduce endoleakage.

Adipose Tissue↗
PubMed2001

Primary pulmonary primitive neuroectodermal tumor (PNET). A case report.

We describe a rare case of a primary primitive neuroectodermal tumor (PNET) in the lung of a 17-year-old girl. Grossly, the tumor, located in the right lower lobe, was relatively well-circumscribed and whitish to yellowish in color with scattered hemorrhagic necrosis. Microscopically, the tumor was composed of ovoid to polygonal cells with a high nuclear to cytoplasmic ratio and relatively scant cytoplasm, arranged in solid sheets with intervening fine fibrovascular stroma. Immunohistochemically, the tumor was positive for the MIC2 gene product, whereas AE1/AE3, CAM5.2, and a variety of neuroendocrine markers such as chromogranin A, synaptophysin, and ProGRP, were negative. Three months after the lobectomy, recurrent tumors were noted in the mediastinum and right thoracic wall, and she died despite combined chemotherapy and radiation therapy. In this case cytogenetic analysis showed a hypertriploid karyotype with multiple numerical and structural chromosomal aberrations, but failed to disclose distinct evidence of translocation between chromosome 11 and 22. However, the reverse transcriptase-polymerase chain reaction (RT-PCR) demonstrated EWS/FLI-1 fusion transcripts, confirming the histopathologic diagnosis of PNET. This case indicates that the primary pulmonary PNET is a highly aggressive neoplasm occurring at a young age, and should prompt combined systemic chemotherapy, even though it is organ-confined.

Adolescent↗
PubMed2001

Phase I-II study of neoadjuvant chemoradiotherapy followed by radical surgery in locally advanced cervical cancer.

The usefulness of neoadjuvant chemotherapy (NAC) regimens has been reported; however, the effect of NAC for advanced stages (especially stage III-IVA) is thought to be insufficient. We conducted a phase I-II study of neoadjuvant chemoradiotherapy consisting of intra-arterial (i.a.) infusion of carboplatin and intracavitary brachytherapy in patients with locally advanced cervical cancer to achieve the new NAC method. Sixteen eligible patients included those with previously untreated stage IIB, III or IVA cancer with bulky tumor. Brachytherapy using iridium-192 was performed with concurrent i.a. chemotherapy with carboplatin (200, 300 and 400 mg/m2). Treatment was repeated every 4 weeks for a total of two cycles. Both hematologic and non-hematologic toxicities were generally mild. Grade 4 hematologic toxicity was observed in 12.5% and there were no grade III or IV non-hematologic toxicities. The optimal dose of carboplatin was determined to be 400 mg/m2. Among 16 patients, six showed complete response (37.5%) and nine showed partial response (56.3%), for an overall response rate of 93.8%. All 15 responding patients underwent radical surgery with a pelvic lymphadenectomy and postoperative radiotherapy. The combination of brachytherapy and i.a. chemotherapy with carboplatin is a promising regimen for NAC in locally advanced cervical cancer.

Adenocarcinoma↗
PubMed2001

Alteration of integrins by interleukin-1alpha in human pancreatic cancer cells.

INTRODUCTION: Adhesion of tumor cells to extracellular matrix (ECM) proteins plays an important role in tumor invasion and metastasis. AIMS: To investigate the expression of integrins in human pancreatic cancer cell lines and its alteration by interleukin (IL)-1alpha to examine the mechanism of adhesion of metastatic human pancreatic cancer cells to ECM proteins. METHODOLOGY: The expression of integrin subunits and their alteration by IL-1alpha were examined by flow-cytometric analysis and cellular enzyme-linked immunosorbent assay in three metastatic human pancreatic cancer cell lines (AsPC-1, BxPC-3, and SW1990) and two nonmetastatic cancer cell lines (PaCa-2 and PANC-1). In addition, assays of cancer cell adhesion to ECM proteins were performed to investigate if increased integrin expression actually affected the adhesive interaction between cancer cells and the putative integrin ECM ligands. RESULTS: The alpha(6) subunit expressed in metastatic cancer cells was enhanced by IL-1alpha. Metastatic cancer cells also showed preferential adherence to laminin compared with nonmetastatic cancer cells, and this was enhanced by IL-1alpha. CONCLUSION: In pancreatic cancer, the enhancement of alpha(6)beta(1) integrin by IL-1alpha through IL-1 receptor type I, as well as the expression of alpha(6)beta(1) integrin, plays an important role in metastasis formation.

Antigens, CD↗
PubMed2001

Post-transplant malignant lymphoma with monoclonal immunoglobulin gene rearrangement and polyclonal Epstein-Barr virus episomes.

This report describes the case of an 8 year old boy who developed ileocecal B cell lymphoma after liver transplantation. The patient underwent orthotopic liver transplantation for biliary atresia and had been given immunosuppressive drugs--cyclosporin A and tacrolimus hydrate. Six years after the liver transplantation, the patient had a sudden onset of fever and abdominal pain. Necropsy revealed an ileocecal mass that was a B cell lymphoma. Epstein-Barr virus (EBV) encoded RNA 1 was demonstrated in lymphoma cells and hyperplastic follicular germinal centre cells in various tissues. Although monoclonal immunoglobulin gene rearrangement was detected in the liver, EBV episomes were of polyclonal origin and lytic forms of EBV were also demonstrated by Southern blotting. Immunohistochemically, lymphoma cells were positive for p53 but negative for latent membrane protein 1 and EBV nuclear antigen 2. These findings suggested that this B cell lymphoma might have occurred sporadically, regardless of EBV infection.

Biliary Atresia↗
PubMed2001

Tolerance to nitroglycerin induced by isosorbide-5-mononitrate infusion in vivo.

We examined the development of tolerance to nitroglycerin (glyceryl trinitrate; GTN) in the rat when isosorbide-5-mononitrate (ISMN) or GTN was continuously infused. Under pentobarbital anesthesia (60 mg/kg, i.p.), mean arterial blood pressure was measured via the left common carotid artery. Bolus injection of ISMN (0.25-250 mg/kg) and GTN (0.25 microg/kg-2.5 mg/kg) was made into the right external jugular vein. ISMN (2.5 mg/h/rat for 7 d), GTN (1.3 microg/h/rat for 7 d), or GTN (0.2 mg/h/rat for 3 d) was infused continuously using an osmotic pump embedded subcutaneously. Bolus injection of ISMN and GTN decreased arterial blood pressure in a dose-dependent manner. The hypotensive effect of ISMN was 2000 times less potent than that of GTN. The GTN-induced hypotensive effect was not affected after continuous infusion of ISMN, whereas it was attenuated after continuous infusion of GTN at either dose. Chronic treatment with ISMN does not induce GTN tolerance as easily as treatment with GTN.

Animals↗
PubMed2001

[Lipid emulsion].

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Contraindications↗