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Biomedical subjects

T Shibuya

Publications and source records attributed to T Shibuya.

At least 289 records · Page 16Linked to original sources
PubMed1988

Establishment and characterization of a cultured cell line derived from nitrosamine-induced pancreatic ductal adenocarcinoma in Syrian golden hamsters.

Seven kinds of pancreatic ductal adenocarcinomas induced by N-nitrosobis(2-hydroxypropil)amine in Syrian golden hamsters were established as transplantable tumor lines on syngeneic animals. These tumor lines were all well or moderately differentiated adenocarcinomas, showing various velocities of growth, unrelated to the grade of histological differentiation. A cell line, designated HaP-T1, was established in continuous tissue culture from one of these homografts. The cells grew in a monolayered sheet with an approximately 17-hour population doubling time. Chromosomal analysis revealed that the modal chromosomal number of the cell line was 44. HaP-T1 cells showed apparent tumorigenicity both on syngeneic hamsters and athymic nude mice, but they grew much faster when injected into the former animals. Morphological characteristics of HaP-T1 cells and tumors induced by HaP-T1 inoculation in both animals revealed apparent epithelial characteristics resembling ductal adenocarcinoma of the pancreas. These transplantable tumor models will contribute to the further investigation in the field of pancreatic cancer.

Animals↗
PubMed1988

Improved regional and global diastolic performance in patients with coronary artery disease after percutaneous transluminal coronary angioplasty.

To investigate the improvement of left ventricular (LV) function after successful percutaneous transluminal coronary angioplasty (PTCA), we studied resting ejection fraction, regional ejection fraction, filling fraction as an index of early diastolic performance, and regional filling fraction in 22 patients with single-vessel coronary artery disease and technically adequate LV angiograms before and 6 months after successful PTCA without restenosis. Before PTCA, filling fraction was significantly less in patients with coronary artery disease than in the control group, although there was no significant difference in ejection fraction. Filling fraction improved significantly after PTCA. Regional filling fraction increased significantly in jeopardizing myocardium, but regional filling fraction in nonjeopardized myocardium did not change significantly. Ejection fraction and regional ejection fraction did not change significantly after PTCA. Our results indicate that the improvement of regional diastolic performance in jeopardized myocardium may contribute to the improvement of global diastolic performance after successful PTCA.

Adult↗
PubMed1988

Effect of human G-CSF on clonogenic cells in acute myeloblastic leukemia.

The effects of purified human native granulocyte colony-stimulating factor (G-CSF) on the growth of clonogenic leukemic blast cells from 10 Japanese patients with acute myeloblastic leukemia (AML) were studied, using an in vitro leukemic blast colony assay. The clonogenic leukemic blast cells from six patients with AML were stimulated to form colonies in viscous medium in vitro by the addition of 100 ng/ml G-CSF. The possibility that G-CSF may be a leukemic blast growth factor warrants further attention.

Adult↗
PubMed1988

Role of coronary collateral vessels during transient coronary occlusion during angioplasty assessed by hemodynamic, electrocardiographic and metabolic changes.

The clinical role of collateral vessels was evaluated during transient coronary occlusion by percutaneous transluminal coronary angioplasty in 22 patients with (8) and without (14) collateral vessels. Coronary occlusion pressure, the ratio of mean coronary occlusion pressure to mean aortic pressure and myocardial perfusion pressure at 40 s of balloon inflation were significantly higher in patients with than in patients without collateral vessels. The changes in left ventricular systolic and end-diastolic pressure, maximal rate of rise of left ventricular pressure (peak dP/dt) and maximal rate of fall of left ventricular pressure (negative peak dP/dt) during balloon inflation were less in patients with than in patients without collateral vessels. Myocardial lactate was produced in patients without collateral vessels but not in those with such vessels. Marked ST segment elevation in the electrocardiogram occurred in patients without collateral vessels but either ST segment depression or mild ST segment elevation was observed in patients with collateral vessels. This study indicates that collateral vessels limit myocardial ischemia during coronary occlusion, probably as a result of increased myocardial perfusion pressure.

Adult↗
PubMed1988

Demonstration of three distinct immunological disorders on erythropoiesis in a patient with pure red cell aplasia and autoimmune haemolytic anaemia associated with thymoma.

A patient with pure red cell aplasia (PRCA) and autoimmune haemolytic anaemia (AIHA), associated with a thymoma which had already been removed, was studied in order to investigate the pathogenesis of PRCA and AIHA. The autoantibody eluted from the surface of the patient's red blood cells (RBC) reacted with the large E antigen of the Rh complex. Immunoglobulin-G (IgG) purified from the patient's serum suppressed CFU-E and BFU-E but not CFU-GM colony formation in the presence of complement. This antibody was not adsorbed with large E antigen. T-lymphocytes in the bone marrow suppressing autologous CFU-E and BFU-E colonies were demonstrated. Thus, three distinct immunological disorders on erythropoiesis were present in this patient with PRCA and AIHA associated with thymoma in a thymectomized state.

Anemia, Hemolytic, Autoimmune↗
PubMed1988

Haematopoiesis in the aged as studied by in vitro colony assay.

Changes occurring in human haematopoiesis with advancing age were studied using an in vitro haematopoietic colony assay in 22 elderly subjects with unexplained anaemia, and in 15 elderly and 15 young subjects without anaemia. Both elderly groups were found to have significantly lower numbers of bone marrow early erythroid-committed progenitors (BFU-E) than the young controls. The elderly anaemic group also showed significantly lower numbers of granulocyte/macrophage progenitors (CFU-GM) than the young controls. However, the responses of the erythroid-committed progenitors in the elderly groups to erythropoietin and burst-promoting activity were similar to those observed in the young controls. Therefore, it is probable that anaemia tends to occur easily in elderly individuals as a result of reduction of reserves of haematopoietic progenitors with advancing age.

Adult↗
PubMed1988

Alterations in the glomerulus in aminonucleoside nephrosis in analbuminemic rats.

Whether obliteration of glomerular epithelial foot processes and increases in urinary N-acetyl-beta-D-glucosaminidase (NAG) activity are the consequence or the cause of proteinuria after administrations of the aminonucleoside of puromycin was examined using Nagase analbuminemic rats. The administration of puromycin aminonucleoside to Nagase analbuminemic rats did not induce proteinuria. However, the increase in urinary NAG activity and the degree of abnormality of foot processes in the glomerular cells were similar to those in control Sprague-Dawley rats. These findings suggest that NAG excretion and the morphological alterations of epithelial cells in nephrosis are not the consequence of massive proteinuria.

Acetylglucosaminidase↗
PubMed1988

The role of prostacyclin during exercise in patients with chronic angina pectoris.

To determine changes in platelet activity, prostaglandin metabolism and catecholamine release along with changes in hemodynamics during exercise, we measured these parameters before and immediately after treadmill exercise. Measurements were made on peripheral arterial blood simultaneously with a direct aortic pressure recording in 30 patients with coronary artery disease (Group 1), in 20 patients without significant coronary disease (Group 2), and in 11 young healthy volunteers as controls. At the peak of the exercise regimen, the ST segment depression was found to be significantly lower in Group 1 than in Group 2, whereas the changes in the DPTI/TTI ratio in Group 2 and the controls decreased with the increase in the duration of exercise. The increased serum lactate level at the intermediate level of exercise (420 +/- 20 sec) was significantly lower in the controls than in the other 2 groups. Changes in beta thromboglobulin, platelet factor 4, and plasma norepinephrine were similarly increased in all 3 groups by exercise. At the termination of exercise, however, 6 keto-prostaglandin F1 alpha in Group 1 was insignificantly elevated, whereas it increased from 42.9 +/- 7 pg/ml to 55.7 +/- 7.1 (p less than 0.05) in Group 2 and from 38.2 +/- 5.7 pg/ml to 45.1 +/- 6.8 (p less than 0.01) in the controls. These results suggest that decreased prostacyclin production in the vessel wall might be an indicator of myocardial ischemia, and that the administration of prostacyclin may modulate the coronary vascular tone exaggerated by exercise.

Adult↗
PubMed1988

[Improved survival rates in Hodgkin's disease].

Results of treatment of 25 Hodgkin's disease patients at Kyushu University Hospital from 1981 to 1985 were reviewed. Total nodal irradiation or MOPP chemotherapy was used mainly. The actuarial 5-year survival rate, 87.2%, was significantly better than the 41.0% of 61 patients treated between 1966 and 1980 (P less than 0.01). However, 12 of the 24 patients in remission eventually relapsed. To further improve the survival rates of patients with Hodgkin's disease, technical improvements in total nodal irradiation and altering Adriamycin-containing chemotherapy protocol from MOPP chemotherapy are advisable.

Adult↗
PubMed1988

Growth of clonogenic myeloblastic leukemic cells in the presence of human recombinant erythropoietin in addition to various human recombinant hematopoietic growth factors.

The effects of human recombinant erythropoietin (rEpo) in the presence of other stimulators on the growth of clonogenic leukemic blast cells from ten Japanese patients with acute myeloblastic leukemia were studied with an in vitro leukemic blast colony assay in methylcellulose culture. With the addition of rEpo alone, no leukemic blast colony formation was stimulated in any of the cases examined. However, when rEpo and phytohemagglutinin lymphocyte-conditioned medium (PHA-LCM) were added to the culture simultaneously, in contrast to results with PHA-LCM alone, the number of leukemic blast colonies formed was significantly increased in two of the ten cases (P less than .01). These two cases were classified as M1 according to the French-American-British (FAB) classification. This enhancing effect of rEpo was observed with human recombinant granulocyte/macrophage colony-stimulating factor (rGM-CSF) or human recombinant interleukin-3 (rIL-3) but was not observed with human recombinant granulocyte CSF (rGCSF).

Cell Division↗