Biomedical subjects
M Takeuchi
Publications and source records attributed to M Takeuchi.
[Studies on uterine contractions].
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Air-containing urinoma: an unusual complication associated with pyelolithotomy.
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Persistence of recruitable coronary collaterals in the absence of coronary vasospasm in a patient with variant angina.
Recruitable coronary collaterals may appear when spasm suddenly occludes the coronary artery. We report a patient with variant angina who had visible collateral vessels on a control coronary angiogram, despite the presence of normally appearing coronary arteries. These collaterals disappeared after intracoronary administration of nitroglycerin. These findings suggest that recruitable collateral vessels can remain patent long after spontaneous attacks of angina have resolved, and become visible when there is a pressure difference between two small coronary arteries.
Does coronary stenting following balloon angioplasty improve myocardial fractional flow reserve?
PURPOSE: Suboptimal distal coronary flow reserve after successful balloon angioplasty has been attributed to angiographically unrecognized inadequate lumen expansion, and adjunct coronary stenting has been shown to improve coronary flow reserve. The aim of this study was to investigate whether myocardial fractional flow reserve (FFRmyo) would increase further after coronary stenting compared with balloon angioplasty alone in the same patient group. METHODS: FFRmyo and quantitative coronary angiography were obtained before and after pre-stent balloon dilation, and again after stent placement in 11 patients (7 left anterior descending artery, 3 right coronary artery and 1 left circumflex artery). FFRmyo was calculated as the ratio of Pd/Pa during intracoronary adenosine 5'-triphosphate (50 micrograms and 20 micrograms in the left and right coronary arteries, respectively)-induced maximum hyperemia, where Pd represents mean distal coronary pressure measured by a 2.1 Fr infusion catheter and Pa represents mean aortic pressure measured by the guiding catheter. RESULTS: Percent diameter stenosis significantly decreased after balloon angioplasty (74% +/- 15% vs 37% +/- 17%, p < 0.001), and decreased further after stent placement (18% +/- 10%, p < 0.001 vs baseline and balloon angioplasty). FFRmyo after coronary stenting (0.85 +/- 0.09) was significantly higher than that at baseline (0.51 +/- 0.16, p < 0.001) and after balloon angioplasty (0.77 +/- 0.11, p < 0.05). There was a significant correlation between angiographic variables and FFRmyo. The increase in lumen dimensions after coronary stenting was followed by a further significant improvement of FFRmyo. CONCLUSION: These results suggest that coronary stenting may provide a more favorable functional status and lumen geometry of residual coronary stenosis compared with balloon angioplasty alone.
Establishment of an epidermal growth factor-dependent, multipotent neural precursor cell line.
We have established a multipotent clonal cell line, named MEB5, from embryonic mouse forebrains after the infection of a retrovirus carrying E7 oncogene of human papillomavirus type 16. MEB5 cells proliferated in serum-free, epidermal growth factor (EGF)-supplemented medium. They expressed markers for neural precursor cells (nestin, A2B5, and RC1) and did not express markers for neurons (class III beta-tubulin), astrocytes (glial fibrillary acidic protein), and oligodendrocytes (galactocerebroside). MEB5 cells were stably maintained in an undifferentiated state with a diploid karyotype in the presence of EGF. When they were deprived of EGF, about 50% of the cells died due to apoptosis within 24 h. The remaining cells differentiated into neurons, astrocytes, or oligodendrocytes within 2 wk. The newly developed cells with neuronal morphology were immunoreactive for gamma-aminobutyric acid and exhibited neuronal electrophysiological properties. When MEB5 cells were treated with leukemia inhibitory factor for 7 d, they were induced to differentiate exclusively into astrocytes. These results indicate that MEB5 is a cell line with characteristics of EGF-dependent, multipotent neural precursor cells. This cell line should provide a good model system to study the mechanisms of survival, proliferation, and differentiation of the multipotent precursor cells in the central nervous system.
Reliability and validity of the Japanese version of the Tridimensional Personality Questionnaire among university students.
The Tridimensional Personality Questionnaire (TPQ) is a self-rating questionnaire, based on a general biosocial theory, for the clinical description and classification of both normal and abnormal personality variants. It was translated into Japanese and administered with the General Health Questionnaire (GHQ) and the 10-item version of the Social Desirability Scale (SDS) to 450 university students on two occasions 2 months apart. Pearson Product-Moment Correlation Coefficients and kappa-coefficients between TPQ scale scores for the two occasions were significantly high, as were Cronbach's alpha-coefficients of TPQ scales and subcategories at the first wave. Correlations between the TPQ scale score and GHQ and SDS scores were negligible. The TPQ thus appears to have test-retest reliability and content validity among a Japanese student population; it is uninfluenced by psychiatric morbidity or social desirability.
Differentiation of Th1 and Th2 cells in lymph nodes and spleens of mice during experimental autoimmune uveoretinitis.
PURPOSE: Experimental autoimmune uveoretinitis (EAU) is a T-cell-mediated autoimmune disease that can be elicited in susceptible rodent strains by immunization with a retinal autoantigen, such as interphotoreceptor retinoid-binding protein (IRBP). In this study, we investigated whether there is a correlation between inflammation in the eye and T-helper (Th)1- and Th2-type responses in the lymph nodes and the spleen after immunization of B10.A mice with IRBP. METHODS: B10.A mice were immunized with IRBP emulsified with complete Freund's adjuvant (CFA), and eyes were then enucleated for histological examination of EAU at 1, 2, 4, 6, or 8 weeks after immunization. In addition, lymph node cells and spleen cells were collected, and cultured with IRBP to measure T-cell proliferation responses and Th1-type (interleukin [IL]-2, interferon [IFN]-gamma), Th2-type (IL-4, IL-10) cytokine production. RESULTS: Pathologically, severe ocular inflammation occurred 2 weeks after IRBP immunization, persisted for 2 weeks, and then gradually resolved. Interleukin-2 and IFN-gamma production were observed in draining lymph node cells at 1 and 2 weeks after IRBP immunization. Those responses then diminished, whereas IFN-gamma production by spleen cells was observed from week 1, peaked at week 4, and gradually decreased. Alternatively, significant production of IL-4 or IL-10 by draining lymph node cells was not detected at any time point. Both IL-4 and IL-10 production by spleen cells was observed at week 6. CONCLUSIONS: Th1-type responses were observed early in draining lymph nodes, then in the spleen after IRBP immunization. The levels of IFN-gamma production by spleen cells reflected the severity of EAU, confirming their pathogenic role in this disease. Th2-type responses were generated in the spleen only as the disease receded, suggesting a role for Th2 cells in the spontaneous termination of EAU.
An unique CD4+CD8+ intestinal intraepithelial lymphocyte specific for DnaK (Escherichia coli HSP70) may be selected by intestinal microflora of rats.
We have previously shown an age-associated increase in unique CD4+CD8+ intestinal intraepithelial lymphocytes (i-IEL) in rats. To elucidate the potential causes of the increase in CD4+CD8+ i-IEL with age, we analyzed the specificity of the CD4+CD8+ i-IEL and influence of intestinal microflora on the increase in this subset in aged rats. The purified CD4+CD8+ i-IEL proliferated in response to DnaK [Escherichia coli (E. coli) HSP70] in the presence of mitomycin-c (MMC)-treated syngeneic spleen cells. The proportion of CD4+CD8+ T cells in whole i-IEL were significantly increased in aged rats fed commercial (CL-2) diet but not in those fed home-made (purified) diet under conventional condition. No CD4+CD8+ i-IEL were detected in aged rats under germfree condition, irrespective of diet feeding. A larger number of Enterobacteriaceae, especially E. coli, were detected in the intestinal contents and feces from aged rats with CD4+CD8+ i-IEL compared with those from aged rats fed without CD4+CD8+ i-IEL. The unique CD4+CD8+ i-IEL population specific for E. coli HSP may be associated with long term exposure to intestinal E. coli in aged rats.
Hamster cardiac xenograft in rat ear: effect of cyclosporine A and leflunomide on survival.
The survival was determined of hamster-heart grafts subcutaneously placed in rat ears. Thirteen out of the 14 grafts tested in rats without immunosuppression were rejected by day 7 post-transplantation, and the one graft was rejected by day 9. Cyclosporine A fully protected the grafts for 2 weeks, the entire experimental period. By contrast, leflunomide seemed only to delay the graft rejection. The formation of antidonor antibodies was fully suppressed by both drugs. These results reveal a pivotal role of T-cells in this model. The results with leflunomide suggest that this drug preferentially affected humoral responses in our study.
The comparative diagnostic value of dobutamine stress echocardiography and thallium stress tomography for detecting restenosis after coronary angioplasty.
The noninvasive detection of restenosis is clinically important for the subsequent management of patients in whom percutaneous transluminal coronary angioplasty (PTCA) has been performed. The aim of this study was to compare the diagnostic value of dobutamine stress echocardiography (DSE) and stress 201Tl single-photon emission computed tomography (SPECT) for detecting restenosis after PTCA. Fifty-three consecutive patients referred for the evaluation of possible restenosis or whom had been scheduled for follow-up study underwent DSE a mean of 5 months after angiographically successful PTCA. Dobutamine was infused incrementally under two-dimensional echocardiographic imaging. The left ventricle was divided into 16 segments and grouped into three coronary vascular territories. Rest, low-dose, and peak-dose images were digitized and displayed in a quad-screen format. Positive findings for restenosis were defined as new or worsened wall motion abnormality at a previously dilated vascular territory. All but one patient underwent SPECT. Positive findings for restenosis were defined as the presence of redistribution. All patients underwent quantitative coronary angiography after two tests. Restenosis was angiographically demonstrated in 23 (43%) of 53 patients and 25 (42) of 59 vessels. The sensitivity of DSE and SPECT for detecting restenosis was 78% and 74%, specificity was 93% and 93%, and accuracy was 87% and 85%, respectively. In a total of 59 vascular regions, DSE was 76% sensitive and 94% specific for detecting individual restenosis. It is concluded that DSE is comparable in diagnostic accuracy to SPECT for detecting restenosis in patients after PTCA.
Comparison of dobutamine stress echocardiography and stress thallium-201 single-photon emission computed tomography for detecting coronary artery disease.
Dobutamine stress echocardiography and stress thallium-201 single-photon emission computed tomography (SPECT) were compared for detecting coronary artery disease in 120 consecutive patients who underwent concomitant quantitative coronary angiography. The left ventricle was divided into anterior, inferior, and lateral regions. Wall motion or perfusion abnormalities observed within each region were classified as ischemia or fixed abnormality. Both tests showed 81% agreement in all 120 patients. Complete agreement was observed in 77% of the 360 regions analyzed. The overall sensitivity of dobutamine stress echocardiography and thallium-201 SPECT for the detection of coronary artery disease was 85% and 89%, and the specificity was 93% and 85%, respectively. A good correlation was found between the wall motion score index and perfusion defect size at peak stress and at rest (r = 0.70). Dobutamine stress echocardiography and thallium-201 SPECT exhibit a comparable accuracy for diagnosing coronary artery disease, localizing coronary artery stenosis, and detecting regional myocardial abnormalities. The wall motion score index may be useful for evaluating the myocardial area at risk.
The detection of residual ischemia and stenosis in patients with acute myocardial infarction with dobutamine stress echocardiography.
The aim of this study was to validate the usefulness of dobutamine stress echocardiography to detect residual ischemia and significant stenosis at the infarct zone in patients with acute myocardial infarction. Dobutamine stress echocardiography and stress thallium-201 single-photon emission computed tomography were performed on 40 consecutive patients 1 month after the onset of acute myocardial infarction. Dobutamine was infused incrementally, and wall motion score index at the infarct zone was calculated before and at peak dobutamine infusion. The patients were divided into three groups according to the change in wall motion at the infarct zone (improved, unchanged, or worsened wall motion, respectively). Tomographic thallium images of the infarct zone were assessed visually. All patients underwent quantitative coronary angiography, and significant stenosis was defined as 50% or greater stenosis. In patients who showed a persistent defect and significant stenosis of the infarct-related artery, resting thallium-201 single-photon emission computed tomography was performed when possible. There was a significantly higher incidence of residual ischemia at the infarct zone in patients with worsened wall motion (85%) and unchanged wall motion (63%) than in those with improved wall motion (8%). The residual stenosis of the infarct-related artery was more severe in patients with worsened or unchanged wall motion than in those with improved wall motion (worsened 82.6% +/- 17.7%, unchanged 93.7% +/- 12.6%, and improved 37.1% +/- 24.4%). The use of worsened or unchanged wall motion at the infarct zone for detecting significant residual stenosis of the infarct-related artery resulted in a sensitivity of 93% and a specificity of 91%, respectively. Worsened wall motion at the infarct zone by dobutamine stress echocardiography strongly suggests residual ischemia. Conversely, less ischemia and less significant stenosis are associated with improved wall motion. Unchanged wall motion suggests severe residual stenosis and sometimes indicates ischemia. It may reflect a hibernating myocardium, but the prognostic significance of this finding should be determined by revascularization.
Clinical implication of multiple risk factor control in the management of diabetic macrovasucular complications.
Using cross-sectional and prospective analyses, the risk factors for macroangiopathy (MA) in nonobese Type 2 diabetic patients were evaluated. In the cross-sectional study, we determined a cutoff point for each variable at which changes in the prevalence of total MA reached statistically significant levels. In the prospective study, those who met more than four out of seven control criteria as set forth in the Multiclinical Study for Diabetic Macroangiopathy (MSDM) had less risk of MA in Type 2 diabetes initially diagnosed without MA compared with those who fulfilled less than three factors. These results suggest that multiple risk factor control is the most effective and reasonable way to lower the incidence of MA in Type 2 diabetes.
Successful treatment of essential thrombocythemia evolving into agnogenic myeloid metaplasia with interferon-alpha.
PURPOSE: Essential thrombocythemia and agnogenic myeloid metaplasia as one form of idiopathic myelofibrosis are myeloproliferative disorders and are quite rare in children. A patient with essential thrombocythemia that transformed to "adult-type" agnogenic myeloid metaplasia is described. PATIENTS AND METHODS: A routine examination of an 8-year-old girl with bronchial asthma showed thrombocytosis. Essential thrombocythemia was diagnosed 2 years later. During a 3-year follow-up without treatment, transition of the essential thrombocythemia to agnogenic myeloid metaplasia was noticed. The patient had an excellent response to interferon (IFN)-alpha therapy. CONCLUSION: This case is unique because of the availability of premorbid hematologic data and the natural progression of essential thrombocythemia to agnogenic myeloid metaplasia. Whether IFN-alpha therapy can prevent the progression of idiopathic myelofibrosis to leukemia has not yet been determined.
Serum soluble CD44 in pediatric patients with acute leukemia.
PURPOSE: CD44 is an adhesion molecule expressed on a variety of cells, and its level correlates with the metastatic potential of malignant tumors. Serum concentrations of soluble CD44 (sCD44) are elevated in various cancers. The purpose of this study was to measure the serum concentrations of CD44 in pediatric patients with acute leukemia. PATIENTS AND METHODS: Fourteen pediatric patients with acute leukemia were studied. The authors measured the serum concentration of sCD44 by enzyme-linked immunosorbent assay before and after therapy. The concentrations were compared with those of 15 control healthy children and 10 patients with bacterial infections. RESULTS: The mean serum concentration of sCD44 at presentation was significantly higher in patients than in control subjects, but decreased to a normal range in complete remission after chemotherapy. There was no difference in sCD44 concentrations between patients with acute lymphocytic leukemia and those with acute myeloid leukemia. Serum concentrations of sCD44 did not correlate with lactic dehydrogenase concentrations or bone marrow nucleated cell counts and only weakly with peripheral leukocyte count. sCD44 levels in patients with bacterial infections were similar to those of control subjects. CONCLUSION: Serum concentration of sCD44 may reflect disease status in pediatric patients with acute leukemia and might be a useful tumor marker in these patients.
Production of angiotensin-converting enzyme in rat epididymis.
Unilateral ductuli efferentia testis of immature rat were severed in order to interrupt the continuity between testis and epididymis and angiotensin-converting enzyme (ACE) activities were measured 5 weeks after the operation. The epididymal ACE on the operated side increased to nearly the same level as that on the contralateral side, but the testicular ACE activity on the operated side was markedly lower than that on the contralateral side. On immunofluorescent study using antiserum against purified rat lung ACE, ACE could be found in the tubular epithelial cells of the operated epididymis. These results suggest that epididymis itself synthesize ACE without connection to testis.
Cerebral sinus venography in the dog: a new technique.
A new method of performing cerebral sinus venography was developed that opacifies both the ventral and most of the dorsal venous sinus systems. A pediatric angiographic catheter was introduced into the external jugular vein and advanced to the level of the temporal sinus. Iodinated contrast medium was injected manually and radiographs were made. Subtraction radiography was used to visualize vessels filled with contrast medium. Venography was simple and relatively non-invasive and was considered safe. The technique was used to confirm occlusion of the transverse venous sinus in healthy dogs that had undergone radical craniectomies.