Search PubMed⌕ Search

Biomedical subjects

T Uehara

Publications and source records attributed to T Uehara.

At least 163 records · Page 9Linked to original sources
PubMed1996

Cytological distinction between clear cell carcinoma and yolk sac tumor of the ovary.

Cytological characteristics of clear cell carcinoma (CCC) and yolk sac tumor (YST) of the ovary were examined and compared. Indices for differential diagnosis of these two histologically similar but biologically different tumors were analyzed based on cytological features of the tumor cells. The main results obtained were from three cases of CCC and one case of YST who underwent imprint smear or similar examinations. Seventeen cases of CCC and two of YST with positive cytology results, mainly obtained from ascites samples, were also examined. Cytological characteristics of CCC compared to those of YST were: more marked cohesiveness of tumor cells with less-marked pleomorphism, well-preserved cell borders, fine vesicular cytoplasm, evenly thickened nuclear membrane, and fewer nucleoli and multinucleated giant cells in number. Cells with large cytoplasmic vacuolation were infrequent, and hobnail-shaped tumor cells were rather few in number in CCC cases examined. On the other hand, in the case of YST, cells were more dyscohesive, with marked cellular pleomorphism, usually faint cell borders, no thickening of nuclear membrane and occasional presence of nuclear grooves. The "naked" cells were commonly observed. Further, nucleoli were frequently numerous in number, and multinucleated giant cells were frequently found which showed marked cellular and nuclear atypism. These characteristics found mainly in imprint smears were also relatively well preserved in specimens obtained from ascites or other metastatic sites. These findings indicate that detailed cytological examination can provide a means for differential diagnosis of CCC and YST, supplementing other clinical information.

Adenocarcinoma, Clear Cell↗
PubMed1996

Neuronal apoptosis by glial NO: involvement of inhibition of glyceraldehyde-3-phosphate dehydrogenase.

In primary cocultures of neurons and glial cells prepared from the neonatal rat brain, lipopolysaccharide (LPS) reduced the numbers of neuronal cells but the effects were markedly inhibited by NG-monomethyl-L-arginine, indicating the involvement of NO and LPS-induced NO synthase in neuronal death. LPS stimulated the expression of inducible NOS (iNOS) in preparations of primary cultured microglias/astrocytes, but not in primary cultured neurons. In addition, LPS caused DNA fragmentation only in NG108-15 cells but not in primary cultured astrocytes as well as astrocytes in cocultures of the two cell types, suggesting that NOS induces the apoptosis of neurons but not glial cells. We then examined the NO-induced neuronal death in NG108-15 cells using NO donors. SNP, and NO donor, caused NO-2 accumulation in the reaction medium and lactate dehydrogenase (LDH) leakage from NG108-15 cells. Although SNP stimulated guanylyl cyclase and accumulated cGMP, cGMP analogs did not affect LDH leakage. In addition, SNP induced chromosomal condensation and fragmentation of nuclei in NG108-15 cells. Gel electrophoretic analysis of cellular DNA extracted from SNP-treated cells, confirmed the internucleosomal DNA fragmentation typical of apoptosis in this culture. SNP increased the amount of radioisotopic labeled glyceraldehyde-3 phosphate dehydrogenase (GAPDH) in the presence of [32P]NAD and inhibited the enzyme activity. The results suggested that SNP-induced cell death is partly due to the NO-induced inhibition of GAPDH, perhaps by stimulating the binding of NAD to GAPDH.

Animals↗
PubMed1995

Herbimycin A suppresses NF-kappa B activation and tyrosine phosphorylation of JAK2 and the subsequent induction of nitric oxide synthase in C6 glioma cells.

Herbimycin A, a potent tyrosine kinase inhibitor, suppressed nitric oxide synthase (NOS) induced by lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma) in C6 glial cells. LPS activated NF-kappa B, and this effect was inhibited by pretreatment with herbimycin A. In addition, IFN-gamma activated the tyrosine protein kinase, JAK2, and tyrosine-phosphorylation by itself was also inhibited by herbimycin A. These results suggest that herbimycin A suppresses iNOS induction by inhibition of both NF-kappa B activation caused by LPS, and tyrosine-phosphorylation of JAK2 caused by IFN-gamma in C6 glioma cells.

Animals↗
PubMed1995

Wortmannin inhibits insulin-induced Ras and mitogen-activated protein kinase activation related to adipocyte differentiation in 3T3-L1 fibroblasts.

Wortmannin, a specific inhibitor of phosphatidylinositol 3-kinase (PI 3-kinase), inhibited adipocyte differentiation of 3T3-L1 fibroblasts induced by insulin/dexamethasone/IBMX (hormones/IBMX). Insulin as a key factor in the process of the adipocyte differentiation activated PI 3-kinase, Ras protein, and mitogen-activated protein kinase (MAP kinase, ERK) in 3T3-L1 fibroblasts. Pretreatment with wortmannin almost completely suppressed all these activations. These findings suggest that the sequential activation of PI 3-kinase, Ras protein, and MAP kinase is involved in the insulin signaling pathway(s) during differentiation by hormones/IBMX and in consequence of the inhibition of PI 3-kinase by wortmannin, the activation of Ras protein and MAP kinase which acts downstream of PI 3-kinase is suppressed and results in the inhibition of adipocyte differentiation.

3T3 Cells↗
PubMed1995

Possible involvement of protein kinase C and low molecular weight GTP-binding proteins in thrombin-induced histamine secretion in human platelets.

Thrombin and 12-O-tetradecanoylphorbol 13-acetate (TPA) caused histamine secretion from human platelets. To clarify the intracellular signalling mechanism of thrombin-induced histamine secretion, the effects of pertussis toxin (PTX) and botulinus toxin (BTX) on thrombin- and TPA-induced histamine secretion were examined in human platelets. The secretion by thrombin was sensitive to BTX, but not PTX. The secretion by TPA was also inhibited by BTX. These results suggest that protein kinase C and low molecular weight G-proteins sensitive to BTX are involved in histamine secretion.

Arachidonic Acid↗
PubMed1995

Cytopathological features of undifferentiated carcinoma of the ovary.

Cytopathological characteristics of undifferentiated carcinoma of the ovary were examined and reviewed. Seven cases of undifferentiated carcinoma were encountered among 202 malignant ovarian neoplasms in the Saitama Cancer Center. Histologically, two cases contained a minor component of usual Müllerian carcinoma and five others were purely of solid architecture without differentiation. Nevertheless, six cases, four of which were totally undifferentiated histologically, showed cytological features characteristic of adenocarcinoma. The results indicate that even carcinomas histologically diagnosed as undifferentiated may have cytological features of glandular differentiation, which may be Müllerian in origin.

Aged↗
PubMed1995

Proliferative and apoptotic status in endometrial adenocarcinoma.

The contribution of cell proliferation and apoptosis to growth patterns in endometrial adenocarcinoma were investigated. Immunohistochemical staining was carried out by an antibody for Ki-67 proliferative antigen, Ley apoptotic antigen, and oncogene products bcl-2 and p53. Forty cases of endometrial adenocarcinoma were classified as exophytic, endophytic, and mixed exo- and endophytic in light of their vertical growth pattern, and, in each case, the carcinomatous area was divided into three layers by its vertical axis. In all but one case, no zonal distribution of the antigen expression was observed. In one case, an exophytic tumor, Ki-67 expression was intense in the surface layer and Ley expression in the deep layer was also intense, suggesting a correlation between macroscopic growth pattern and cellular growth and apoptotic potential. However, in general, zonal distribution of cell proliferation and apoptosis could not explain the growth morphology of endometrial adenocarcinoma of the uterus and it was suggested that factor(s) other than cell proliferation and apoptosis determine macroscopic growth patterns.

Adenocarcinoma↗
PubMed1995

Myocardial metabolism of 123I-BMIPP in patients with hypertrophic cardiomyopathy: assessment by radial long-axis SPET.

To elucidate the metabolism of free fatty acid in the myocardium of hypertrophic cardiomyopathy (HCM), SPET was performed with 123I-15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP), an analogue of free fatty acid, and with 201Tl in nine patients with HCM and eight healthy volunteers who acted as controls. For quantitative analysis of the apical area, a radial long-axis tomogram was reconstructed every 6 degrees after short-axis tomography. The relative regional uptake (RRU, %) in each segment was obtained by normalizing to the maximal value among all segments. The 3-h washout rate was calculated both for BMIPP and for 201Tl. The ratio of the RRU of BMIPP to that of 201Tl was significantly lower in the apical and antero-septal regions compared with other walls (P < 0.01) in the patients with HCM, whereas uptake of both BMIPP and 201Tl in the controls was homogeneous and there was a significant correlation between them. The coefficient of variation (CV) in all segments in the HCM patients was significantly higher (P < 0.01) than that of the controls both BMIPP and 201Tl, indicating inhomogeneous uptake of BMIPP in the HCM patients. The washout rate of BMIPP over 3 h was significantly higher in the patients with HCM (mean +/- S.D. 26.3 +/- 7.3%) than the controls (18.3 +/- 7.5%, P < 0.05). The ratio of segmental washout rate of BMIPP to that of 201Tl in the HCM patients was increased, especially in the septum and apex.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Usefulness of dipyridamole-thallium imaging in 257 patients with atherosclerotic vascular disease.

We evaluated the usefulness of dipyridamole-thallium imaging for the detection of ischaemic heart disease in 257 patients with atherosclerotic vascular disease (80 patients with arteriosclerosis obliterans, 81 patients with aneurysm of the abdominal aorta, 60 patients with aneurysm of the thoracic aorta and 36 patients with dissecting aortic aneurysm). Clinical evidence of ischaemic heart disease was found in 69 of 257 (27%) patients, including 32 patients with arteriosclerosis obliterans, 23 with aneurysm of the abdominal aorta, 9 with aneurysm of the thoracic aorta and 5 with dissecting aortic aneurysm. Dipyridamole-thallium imaging identified myocardial ischaemia in 49 of 69 (71%) patients with clinical evidence of ischaemic heart disease. Dipyridamole-thallium imaging showed positive results in 67 of 81 (83%) patients with aneurysm of the abdominal aorta. In patients with no clinical evidence of ischaemic heart disease, the results of dipyridamole-thallium imaging were positive in 39 of 188 (21%) patients. Dipyridamole-thallium imaging was positive in 90 of the 257 (35%) patients as a whole. When we combined the patients with positive dipyridamole-thallium imaging with those with negative dipyridamole-thallium imaging but who had clinical evidence of ischaemic heart disease, 42% of all patients had evidence of ischaemic heart disease. Our findings suggest that atherosclerotic vascular disease is strongly associated with ischaemic heart disease and that dipyridamole-thallium imaging is useful for the detection of ischaemic heart disease.

Aged↗
PubMed1995

Scintigraphic assessment of silent myocardial ischaemia after early infarction using myocardial SPET imaging with 201Tl and 123I-MIBG.

To test the hypothesis that myocardial sympathetic denervation reflects silent myocardial ischaemia early after infarction, 12 patients with myocardial infarction but without post-infarction angina pectoris underwent single photon emission tomography (SPET) at rest with 201Tl and 123I-metaiodobenzylguanidine (MIBG) shortly after and 3 months after infarction. Short-axis SPET images at the basal, mid-ventricular and apical portions of the left ventricle were selected, and each short-axis image was divided into eight segments. Tracer uptake in each of the 24 segments was scored using a 4-point scale. The total score in each segment was calculated as the defect score for each image, and the difference between the total defect score for the 201Tl and 123I-MIBG images was calculated as the delta defect score. All 12 patients underwent exercise stress 201Tl scintigraphy 1 month after infarction, and they were divided into two groups: those patients with (Group A, n = 7) and those patients without (Group B, n = 5) transient perfusion defects in the peri-infarcted region without chest pain. For the 123I-MIBG defect score, a marked reduction at 3 months was observed in Group A (24 +/- 12 vs 13 +/- 6; P < 0.01), whereas the defect score remained unchanged in Group B (25 +/- 7 vs 23 +/- 8; N.S.). The delta defect score was significantly reduced in Group A (10 +/- 5 vs 6 +/- 4; P < 0.05), whereas it remained unchanged in Group B. The 123I-MIBG defect score early after infarction was higher than the exercise-induced 201Tl defect score (24 +/- 12 vs 20 +/- 9; P < 0.01), whereas at 3 months post-infarction it was lower than the exercise-induced 201Tl defect score (13 +/- 6 vs 20 +/- 9; P < 0.05). Moreover, effort chest pain during daily activities was noted in 5 of the 7 (71%) patients in Group A within 3 months post-infarction. The results of this study suggest that viable but denervated myocardium (mismatched 123I-MIBG defects) is present in peri-infarcted regions, and that myocardial sensory nervous disturbance, which may co-exist with sympathetic nervous denervation, may induce silent myocardial ischaemia in patients with myocardial infarction.

3-Iodobenzylguanidine↗
PubMed1995

Relationship between the melancholic type of personality (Typus melancholicus) and DSM-III-R personality disorders in patients with major depression.

The relationship between the melancholic type of personality (TM) and DSM-III-R personality disorders (PD) in a sample of 96 outpatients with major depression was investigated using a series of multivariate analyses. The results showed that the personality features of TM were quite different from those of any DSM-III-R PD, including obsessive-compulsive PD, and gave only partial support to the DSM-III-R classification of PD into three clusters. It is suggested that if the personality description of TM be included in the Axis II of DSM-III-R, the description of the Axis could have a wider range of personality features and could be more useful for the clinical praxis and research of depressive patients.

Adult↗
PubMed1995

Perfusion lung scanning before and after percutaneous transvenous mitral commissurotomy--early estimation of lung congestion relief.

Percutaneous transvenous mitral commissurotomy (PTMC) has recently been used to treat mitral stenosis. The aim of this study was to evaluate the usefulness of radionuclide perfusion lung scanning in assessing the effect of PTMC on the relief of lung congestion. We studied 30 patients (7 males and 23 females, mean age 55 years). Perfusion lung scannings were performed within 1 week before and after PTMC. We calculated the ratio of activity in the upper quarter to that in the lower quarter of the right lung (U/L) as an index of lung congestion. After PTMC, the mean mitral valve area increased from 1.1 +/- 0.3 to 1.9 +/- 0.4 cm2, the mean left atrial pressure decreased from 14.8 +/- 6.3 to 9.1 +/- 3.5 mmHg, the mean pulmonary artery pressure decreased from 22.7 +/- 8.6 to 17.4 +/- 6.3 mmHg, and the U/L ratio decreased significantly from 0.89 +/- 0.40 to 0.68 +/- 0.24 (p < 0.0001). The U/L ratio showed greater improvement (4.5%) in patients whose NYHA class improved (n = 19) than in those whose NYHA class did not improve after PTMC. The U/L ratio was closely related to mitral valve area, and left atrial and pulmonary artery pressures. The change in the U/L ration before and after PTMC also reflected symptomatic improvement. In conclusion, U/L ratios obtained from perfusion lung scannings before and after PTMC reflect mitral valve area and pressures, and can be used to assess lung congestion relief after PTMC.

Adult↗
PubMed1995

Glomus tumor of the upper lip.

A case of glomus tumor of the upper lip in a 57-year-old Japanese male is described. The patient had a tender swelling of the upper lip, and this was completely excised. The lesion was found to be encapsulated by fibrous connective tissue and composed of blood capillaries surrounded by sheets of epitheloid cells. Immunohistochemical examination revealed that the neoplastic cells were positive for S-100 protein, vimentin, desmin and actin. Although the endothelial cells of blood capillaries in the tumor tissue were positive for factor VIII, no reaction product was found in the tumor cells. These results suggested that the tumor cells had characteristics of smooth muscle cells.

Actins↗
PubMed1995

[Asymptomatic atheromatous cerebrovascular diseases in patients with acute myocardial infarction--evaluation by brain magnetic resonance angiography].

To investigate the relationship between atherosclerosis in the cerebral and coronary arteries, we examined the prevalence of asymptomatic atheromatous cerebrovascular lesions in patients with acute myocardial infarction (AMI). The subjects consisted of 33 consecutive AMI patients with angiographically proven coronary artery stenosis/occlusion(s) who had no history of ischemic strokes, and 33 age/sex matched controls without a history of coronary heart diseases or/and cerebrovascular diseases. Asymptomatic cerebrovascular lesions were evaluated by magnetic resonance angiography (MRA) with a 3-dimensional time-of-flight method within 2 months after the AMI onset. The evaluated arteries on MRA included the carotid bifurcation and the intracranial arteries (intracranial portion of the internal carotid artery, horizontal portion of the middle cerebral artery, and the basilar artery). Asymptomatic cerebrovascular stenotic lesions (more than 25% stenosis) on MRA were found in 8 AMI patients (24.2%) at the carotid artery bifurcation and 5 (15.2%) in the intracranial arteries, compared to 1 (3.0%) and 3 (9.1%) respectively in control subjects. The lesions in the carotid bifurcation were significantly frequent in the AMI patients (p < 0.05), while those in the intracranial arteries did not differ between the two groups. The AMI patients with the intracranial artery lesions were significantly older than those without such lesions (p < 0.05). The data obtained indicates that the coexistence of asymptomatic atheromatous cerebrovascular diseases, especially the lesions in the carotid bifurcation, should be considered in treating patients with AMI. The older AMI patients, who may have not only extracranial lesions but also intracranial lesions, should be treated more carefully.

Aged↗
PubMed1995

Cell dynamics of undifferentiated carcinomas of the ovary. Immunohistochemical estimation of their growth fraction and apoptotic status.

The proliferative and apoptotic status of undifferentiated carcinomas of the ovary was estimated immunohistochemically by antibody for Ki-67 proliferative antigen and Le(Y) apoptotic antigen. Well-differentiated types of ovarian carcinoma were examined for comparison. In 8 cases of undifferentiated carcinomas, the proliferative activity in terms of the growth fraction expressed as percentage of positive nuclei for Ki-67 antigen ranged from 28.2 to 81.2% (mean 60%). In well-differentiated carcinomas, which included 8 serous, 8 mucinous, 4 endometrioid and 4 clear cell adenocarcinomas, the growth fraction ranged from 8.2 to 33.4% (mean 20%). Thus, statistically significant differences were found in the proliferative activity between undifferentiated and well-differentiated ovarian carcinomas. On the other hand, apoptotic status as estimated by Le(Y) staining varied considerably among the cases in both undifferentiated and differentiated carcinoma groups. Nevertheless, in general, undifferentiated carcinomas seemed to be more prone to apoptosis than well-differentiated carcinomas. It is concluded that in ovarian undifferentiated carcinomas, more active cell proliferation takes place with a concomitant cell loss compared to their differentiated counterparts.

Apoptosis↗
PubMed1995

Atypical polypoid adenomyoma of the uterus in a very old woman. Report of a case with immunohistochemical characterization of its stromal components and proliferative status.

A case of atypical polypoid adenomyoma (APA) of the uterus in an 81-year-old patient is reported. The tumor arose in the uterine fundus as a polypoid mass and measured 9 cm in its longest diameter. Its histological appearance was similar to that of the reported cases, i.e. presence of atypical endometrial glands and a cellular smooth muscle stroma. However, the patient's age was extremely advanced, since APA has predominantly been reported to arise in premenopausal women. APA has been suggested as being related to prolonged estrogenic stimulation. But the fact that in this case the uninvolved endometrium was absolutely atrophic, negated this possibility. Immunohistochemistry for alpha smooth muscle actin was positive diffusely in the stroma. The proliferative status of the neoplastic glands was assessed by immunostaining for Ki-67 antigen. About 30% of the glands contained Ki-67 positive nuclei, and about 3% of the nuclei were positive in the glands. These figures are far below those of the usual endometrial adenocarcinoma, strongly suggesting that the APA was benign in nature.

Adenomyoma↗
PubMed1995

[AIDS control in industry in Okinawa Prefecture, Japan].

To see how industry is responding to AIDS, an anonymous questionnaire survey was conducted on member companies (n = 407) of the chamber of commerce with 50 or more employees in three large cities in Okinawa, during February to March, 1994. Responses were obtained from 221. The questionnaire looked at type of industry, number of employees, number of business trips to foreign countries, specialists for health management, AIDS control, attitudes and actions taken toward infected persons and AIDS patients, etc. The main results were as follows; In 73 companies foreign business trips had been made. The rate of appointment of specialists in health management was below 50%. In 80% of the companies, AIDS control was not in place. About 1/2 of the companies responded that there was a need to grapple with AIDS control while 40% of the companies were undecided. The majority of the companies felt that there was no chance of their employees having HIV infection within five or six years. Many companies had no regulations for dealing with employees who are infected with HIV. From the survey, three points were made clear: 1. Industry does not have an adequate plan to deal with AIDS. 2. There is no awareness of a crisis. 3. There is insufficient dissemination of information regarding AIDS. HIV/AIDS is predicted to increase in industries in our country and management will be hard-pressed to deal with the intricate problems that arise. HIV/AIDS is not exclusively an individual problem, but should be the concern of industries and society as well.(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired Immunodeficiency Syndrome↗