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Biomedical subjects

Y Nishimoto

Publications and source records attributed to Y Nishimoto.

At least 163 records · Page 9Linked to original sources
PubMed1981

[Measurement of cardiac volume by computed tomography (author's transl)].

Noninvasive cardiac volume measurement by computed tomography (CT) was attempted in this study. It was found that non-gated CT images were very close to the end-diastolic images by ECG-gated CT. Ten to fifteen non-gated scannings were obtained serially from the upper atria to the left diaphragm in 9 normal subjects and 72 patients (6 hypertensives, 7 aortic valvular diseases, 22 mitral valvular diseases, 5 shunt lesions and 33 ischemic heart diseases). To demarcate each chamber, contrast enhancement CT was performed by drip infusion in most cases, but it was done by 4-6 times bolus injections at the level of the left ventricle (LV) to visualize LV lumen in ischemic cardiac patients who had ventriculography. The volume was calculated by summing each slice's volume which was obtained from the area times slice thickness (Fig. 2). The total cardiac volume and the volume of each chamber (LA, RA, RV and LV) were calculated. The interventricular septum and LV wall were included into LV volume. There was a good relationship (r = 0.90) between the total cardiac volume by CT and that by chest X-ray (PA and lateral views) (Fig. 4). Each volume by CT in 9 normal subjects was: 353 +/- 30 ml/m2 in total, RA: 53 +/- 17 ml/m2, LA: 54 +/- 21 ml/m2, RV: 90 +/- 15 ml/m2, and LV: 123 +/- 15 ml/m2 (mean +/- SD), respectively, and an increment of each volume was shown according to the hemodynamic features of various heart diseases: the total volume was increased significantly in valvular disease (Fig. 5), RA and RV volumes in mitral valvular disease with tricuspid regurgitation and ASD (Figs. 6, 7) LA volume in mitral valvular disease and shunt lesion (Fig. 8) and LV volume in aortic valvular disease and mitral regurgitation (Fig. 9). Between the left ventricular lumen volume by Ct and its end-diastolic volume by ventriculography (area-length method), there was a good relationship (r - 0.81) in 17 cases without cardiac aneurysms out of 22 ischemic cardiac patients examined by ventriculography (RAO and LAO views) (Fig. 11). The cardiac CT was found very useful for measurements of cardiac volume, since it is noninvasive and quite simple yet reasonably accurate.

Adult↗
PubMed1980

Hygromycin and epihygromycin from a bacterium, Corynebacterium equi No. 2841.

A newly isolated bacterium which produces antibacterial substances as below was taxonomically characterized and identified with Corynebacterium equi. The major antibiotic produced was determined to be hygromycin by direct comparison. The minor component, newly named epihygromycin was proved to be an epimer of hygromycin by spectrosocopic evidences and by chemical conversions. The presence of epihygromycin in the metabolites of Streptomyces noboritoensis (reported to be a hygromycin producer) was also observed.

Amino Acids↗
PubMed1980

[Role of virus inhibitory factor or interferon in the antitumoral effect of whole-body hyperthermia].

The interferon inducing effect of hyperthermia was studied in normal and tumor-bearing mice. Circulating interferon was temporarily detected one day after subcutaneous transplantation of 1.6 X 10(6) Ehrlich's ascites tumor cells. Hyperthermia of 43.5 degrees C for 5 min did not induce the interferon formation in mice with or without subcutaneous tumor of the cells. These findings showed that the induction of interferon formation was not main cause of the hyperthermia-induced tumor inhibition.

Animals↗
PubMed1979

Purification of L-kynurenine 3-hydroxylase by affinity chromatography.

NADP immobilized on agarose is able to adsorb L-kynurenine 3-hydroxylase. The enzyme is released from the adsorbent by passage of a buffer containing 0.5 mM NADP through the column. L-Kynurenine 3-hydroxylase was purified 26-fold with a yield of 12% from mitochondrial outer membrane with a procedure involving DEAE-Sepharose CL-6B, Sephacryl S-200 chromatography and NADP-agarose affinity chromatography. This monooxygenase was a homogeneous protein, giving a monomeric molecular weight of 145,000, which had neither any significant NADPH diaphorase activity nor cytochrome b5-like haem protein. However, the enzyme did not show affinity for a column with L-kynurenine coupled to the gel with a suitable spacer group, and AMP did not serve as an effective ligand in an affinity resin.

Animals↗
PubMed1978

Immunological determination of serum m-AST activity in patients with acute myocardial infarction.

Serum m-AST (mitochondrial isoenzyme of AST) activity in patients with acute myocardial infarction was determined quantitatively by a new immunological technique which is sensitive and easily available. All 31 patients with acute myocardial infarction showed abnormally high levels of serum m-AST (more than 5 KU/ml); the mean serum m-AST activity attained its peak (42.0 +/- 4.9 KU/ml) on the first day after the onset of infarction 5 hours later than that of serum t-AST (total AST) activity in 15 patients whose peak m- and t-AST activities were identified clearly. The individual peak m-AST activity correlated with the total CK released (r = 0.83, n = 15), indicating that the release of m-AST also reflects the infarct size. The ratio of serum m-AST/t-AST increased following myocardial infarction and showed the maximal value (average 25.7%) on the third to seventh day after onset. This ratio in the patients with acute myocardial ifarction was also greater than that in patients with liver disease or with heart failure from causes other than acute myocardial infarction. In the patients who had the additional complication of heart failure and/or cardiogenic shock the ratio was also greater than that is the patients without these hazards. These results indicate that the ratio of serum m-AST/t-AST reflects the severity of the myocardial cellular damage in acute myocardial infarction.

Acute Disease↗
PubMed1977

A method for the estimation of peak serum LDH activity based on a single post-peak level after acute myocardial infarction.

A new method was developed to estimate the peak serum lactic dehydrogenase (LDH) value in patients with acute myocardial infarction from a single determination of serum LDH activity in the post-peak period (3rd to 5th day after the onset of infarction) using nomogram method based on the monoexponential decay of serum LDH with a decay constant of 0.012 hours-1. To develop this nomogram, the serial changes in serum LDH activities were studied in 30 patients with acute myocardial infarction admitted to the coronary care unit within the pre-peak period. The mean errors in estimation from data of the 3rd, 4th, or 5th day after the onset were acceptably small, 10.5 +/- 1.9%, 14.5 +/- 2.8%, and 15.9 +/- 3.3%, respectively. Furthermore, a correction formula was obtained to improve the accuracy of estimation, since the peak values were underestimated in patients with actual peak values less than 300 units and overestimated in the case of more than 500 units. Estimation in 9 patients of an external sample group confirmed that this nomogram is useful clinically with mean errors of less than 25%.

Acute Disease↗