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Biomedical subjects

Y Inagaki

Publications and source records attributed to Y Inagaki.

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

[Flow imaging of the cardiovascular system using magnetic resonance imaging].

Blood flow images by magnetic resonance imaging (MRI) using a 0.25 T unit were evaluated for nine normal volunteers and 108 subjects with a variety of cardiovascular abnormalities. Using the non-gated short-spin echo (SE) technique, blood flow in the cardiovascular systems was not imaged in the normal volunteers. Using end-systolic and end-diastolic SE techniques for the normal subjects, blood flow in the cardiac chambers was not clearly imaged. Blood flow in the ascending aorta and aotric arch often did not appear in the gated SE images of the normal subjects. However, blood flow in the descending aorta was often observed in the gated SE images. Blood flow imaging was demonstrated by both non-gated and gated SE techniques in regions where blood flow was relatively slow; for example, in the left atrium of mitral stenosis, in an aortic aneurysm, in a false lumen of an aortic dissection, and in the left ventricle having old myocardial infarction. Using the non-gated inversion recovery (IR) technique, no blood flow was imaged in the cardiovascular system except in the left atrium of one case with mitral stenosis. Using the non-gated short SE technique, there was good correlation between the thrombus formation and the presence of blood flow images in the left atria of 17 patients with mitral stenosis, and in the aneurysmal portions of the aorta or in the false lumens of aortic dissection of 18 patients. It was suggested that mural thrombi in such diseases were related to the relatively slow blood flow. Blood flow imaging easily distinguished stagnant blood flow from mural thrombi using non-gated short SE, end-systolic SE, and IR techniques. Thus, blood flow imaging using MRI should become an important means of evaluating the cardiovascular system.

Adult↗
PubMed1988

[Right ventricular function in cardiovascular disease evaluated by magnetic resonance imaging].

The usefulness of ECG-gated magnetic resonance imaging (MRI) in evaluating right ventricular architecture and function was assessed by measuring right ventricular wall thickness, wall motion, and areas of the right ventricular cavities of seven normal subjects and 46 with cardiac disease, including atrial septal defect (ASD: six cases), hypertrophic cardiomyopathy (HCM: 19), dilated cardiomyopathy (DCM: eight), and old myocardial infarction (OMI: 13 cases). A superconductive MRI system was used. Transverse images at the level of the tricuspid valve were obtained for measurements. ECG-gated MRI clearly showed the right ventricular myocardium throughout the cardiac cycles and facilitated measuring wall thickness and cross-sectional areas of the right ventricular cavity in all subjects. In normals the mean value and standard deviation of the anterior wall thickness of the right ventricle and the area index of the right ventricular cavity at end-diastole were 3.4 +/- 0.7 mm and 10.6 +/- 1 cm2/m2, respectively. The anterior and lateral walls and tricuspid annulus moved inward to the right ventricular cavity in systole, and the excursion of the lateral wall and tricuspid annulus was larger than those of the anterior wall. The interventricular septum (IVS), however, moved outward to the left ventricle in systole. The anterior wall thickness of the right ventricle in patients with HCM was 5.8 +/- 1.4 mm thicker than that of normal subjects. In contrast to normals, the area index of the right ventricular cavity was larger in patients with ASD (18.4 +/- 5.4 cm2/m2) and smaller in patients with HCM (9.1 +/- 1.6 cm2/m2). The IVS moved inward in all patients with ASD and in several patients with HCM. The anterior and lateral wall motion was decreased in patients with ASD and DCM.

Adult↗
PubMed1988

[Deformity of the cardiac structures in patients with mitral valve prolapse: the relationship with flat chest].

In view of the close relationship of mitral valve prolapse (MVP) and chest deformity, seven patients of MVP associated with flat chest were echocardiographically evaluated, and the results were compared with those of 43 normal control subjects, 29 cases with flat chest, and patients with MVP either of the anterior (25 cases) or posterior (21 cases) leaflet. MVP associated with flat chest was observed in the anterior leaflet in all cases. MVP was related to the dislocation of the two mitral leaflets caused by the displaced posterior mitral ring observed by two-dimensional echocardiography. The transition type was observed among the cases with or without dislocation of the mitral ring in cases with flat chest.

Adolescent↗
PubMed1987

Presence of different types of procollagen messenger RNAs in human hepatoma cell lines.

Human hepatoma cell lines were shown for the first time to contain various types of procollagen mRNAs. The amounts and types of procollagen mRNAs differed depending on the cell lines. Pro alpha 1 (III) and pro alpha 1 (IV) collagen mRNAs were present in PLC/PRF/5, a hepatocellular carcinoma cell line, whereas pro alpha 1 (I), pro alpha 2 (I), pro alpha 1 (IV) and pro alpha 2 (V) collagen genes contrast, HepG2 cells derived from hepatoblastoma contained little, if any, mRNAs for these types of procollagens we had examined.

Actins↗
PubMed1987

Effect of ramipril, a new angiotensin converting enzyme inhibitor, on diurnal variations of blood pressure in essential hypertension.

The effect of ramipril on diurnal variations of blood pressure was studied in patients with mild to moderate essential hypertension in groups given once- (n = 18) and twice-daily (n = 21) administration with daily dosages ranging from 2.5 to 10 mg. After ramipril treatment, the blood pressure of patients in both groups was significantly reduced, and no significant differences in diurnal variation of blood pressure were observed between the 2 groups. The pulse rate did not change after administration of ramipril and no serious side effects were observed. In consideration of patient compliance, once-daily administration of ramipril seems to be optimal for the treatment of essential hypertension.

Adult↗
PubMed1987

Efficacy and safety of ramipril (HOE 498) in the treatment of hypertension: dose finding study.

An open-label, prospective multicenter trial of ramipril was performed. The agent was administered once daily at an initial dosage of 1.25 mg and this was increased, when necessary, up to 10 mg with intervals of 2 weeks for 8 weeks. Effectiveness in 46 patients with mild to moderate essential hypertension was 28.1% at a dosage of 1.25 mg, 52.2% at 2.5 mg, 69.6% at 5 mg and 78.3% at 10 mg of ramipril alone. In 27 patients receiving baseline therapy with a thiazide diuretic, a subsequent administration of ramipril showed effectiveness in 11.1% for 1.25 mg, 48.1% for 2.5 mg and 70.4% for 5 mg. Adverse effects occurred in 11.7% of patients overall and were not serious. One patient was withdrawn because of severe headache; the other patients tolerated the treatment well. A dosage of 2.5 to 10 mg of ramipril will probably be appropriate for further evaluation of the effectiveness of this agent in a double-blind study.

Adult↗
PubMed1987

Noninvasive quantification of regional myocardial blood flow and ammonia extraction fraction using nitrogen-13 ammonia and positron emission tomography.

This report describes the theoretical basis and a method to quantitate regional myocardial blood flow (RMBF) and ammonia extraction fraction (E) in man, noninvasively, with N-13 ammonia and positron emission tomography (PET). Two patients with hypertrophic cardiomyopathy, whose left ventricular (LV) walls were markedly thick, were employed in this study to avoid partial volume effects and cross contamination between LV walls and blood pool. RMBF and E were calculated from time-activity curves of myocardial tissue and left atrium derived from serial 6-second PET images of the heart. The time-activity curve of left atrium was used as an arterial input function. The results were RMBF = 67 +/- 4 ml/min/100 g, E = 80 +/- 13% and 65 +/- 10 ml/min/100 g, 81 +/- 16% for each patient. The validity of the present method was discussed.

Ammonia↗
PubMed1987

Transformation of NIH/3T3 cells by DNA from a human hepatoma cell line with integrated hepatitis B virus DNA.

We have studied by means of DNA-mediated gene transfer the transforming activity of the DNA of the human hepatoma cell line HCC-M, which contains genomes of hepatitis B virus (HBV) in integrated form. DNA from HCC-M induced transformed foci on transfection of NIH/3T3 cells. DNAs from primary transformants were capable of inducing secondary transformants. Most of the DNAs of these transformants were demonstrated to contain both human repetitive sequences and HBV DNA, indicating that the transformants had incorporated exogenous human DNA and HBV DNA as well. These results suggest that transformation occurs as the result of the transfer of oncogene which might be closely associated with HBV genome.

Carcinoma, Hepatocellular↗
PubMed1987

Ripple pigmentation of the neck in atopic dermatitis.

Ripple pigmentary lesions of the neck were observed in 12 patients with atopic dermatitis. Biopsy specimens from three cases revealed no amyloid substances. From the review of cases with either atopic dermatitis or ripple pigmentation seen in our hospital, it was concluded that ripple pigmentation of the neck was always associated with atopic dermatitis and appeared in 1.7% of all 751 patients with atopic dermatitis. It is suggested that ripple pigmentation is not necessarily specific or diagnostic of amyloidosis, as is generally believed. Possible relationships involving ripple pigmentation, atopic dermatitis, and macular amyloidosis are also discussed.

Adolescent↗
PubMed1987

Identification of the DNA sequence required for transposition immunity of the gamma delta sequence.

A plasmid containing the transposon gamma delta sequence was immune to further insertion of gamma delta (transposition immunity). Plasmids carrying a fragment containing either 0.2 kilobase pairs of the gamma end or 0.4 kilobase pairs of the delta end of the gamma delta sequence were immune, and other parts of the gamma delta sequence did not confer immunity. The terminal 38-base-pair (bp) sequence of the delta end of the gamma delta was sufficient to confer immunity, the 38-bp sequence of the gamma end conferred only moderate immunity, and the terminal 35-bp sequence, which was completely identical at both the gamma and delta ends, was insufficient to confer immunity.

Base Sequence↗
PubMed1987

[Diagnostic evaluation of ischemic heart disease by X-ray computed tomography and magnetic resonance imaging].

To assess the usefulness of X-ray computed tomography (CT) and magnetic resonance imaging (MRI) in detecting and evaluating ischemic heart disease, conventional and enhanced CT were performed for 180 patients (150 with transmural infarction, 12 with subendocardial infarction, and 18 with angina pectoris). MRI examinations were performed for 38 patients (31 with transmural infarction, three with subendocardial infarction, and four with angina pectoris). With enhanced CT, two findings in the myocardium were direct evidence of myocardial infarction: 1. filling defects on the early scans, and 2. late enhancement of the myocardium on the delayed scans. The former were observed mainly at the sites of recent anterior myocardial infarction and the latter were seen in about half of the patients with recent and remote anterior myocardial infarctions. However, these findings were inadequately imaged in patients with inferoposterior infarction and subendocardial infarction. Among 137 patients with transmural infarction, enhanced CT revealed left ventricular aneurysms in 51 (37%) and ventricular thrombi in 26 (19%). ECG-gated MRI apparatus having a superconducting magnetic operating at 0.25 Tesla was used, and data for this study were collected using the single-slice spin echo technique. In eight of nine patients with acute myocardial infarction, gated MRI demonstrated the infarcted myocardium as regions of high signal intensity relative to that of the adjacent normal myocardium. Such a difference in MRI signal intensity was scarcely recognized in the chronic stage of myocardial infarction, but the indirect findings of infarction, such as regional wall thinning, wall motion disturbances, left ventricular aneurysms, and ventricular thrombi were easily detected using MRI. No characteristic finding was obtained by CT or MRI in patients with angina pectoris.

Aged↗