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K Tanabe

Publications and source records attributed to K Tanabe.

At least 307 records · Page 17Linked to original sources
PubMed1996

[Relationship between ischemic ST depression and oxygen uptake kinetics during ramp exercise test in patients with effort angina].

The relationship between ischemic ST depression and oxygen uptake kinetics was examined during cardiopulmonary exercise test using the ramp protocol in 22 patients (17 males and 5 females, mean age 61.4 +/- 8.1 years) with ischemic ST change (horizontal or down sloping ST depression over 1 mm) during a previous multi-stage exercise test (Bruce method). Patients were classified into three groups according to coronary angiographic findings: absence of significant stenosis group (control, n = 7), single-vessel disease group (n = 7) and multivessel disease (MVD) group (n = 8). Peak exercise time, peak heart rate, peak systolic blood pressure, anaerobic threshold, peak oxygen uptake (peak Vo2), exercise time, heart rate, systolic blood pressure, and oxygen uptake at appearance of ischemic ST change were measured. The ratio of oxygen uptake increase at appearance of ischemic ST change was calculated. Peak Vo2 was lower in the MVD group than in the control group (20.9 +/- 6.2 vs 27.3 +/- 3.3 ml/min/kg, p < 0.05), and exercise time from the beginning of ramp exercise to the appearance of ischemic ST depression was shorter in the MVD group than in the control group (5.2 +/- 2.1 vs 8.2 +/- 1.9 ml/min/kg, p < 0.05). The ratio of oxygen uptake increase was smaller in the MVD group than in the control group (0.7 +/- 0.3 vs 1.2 +/- 0.2, p < 0.01). These results could be caused by impaired increase of cardiac output due to myocardial ischemia occurring during exercise. In the clinical setting, these phenomena could be used as a parameter for differentiating ischemic from non-ischemic ST depression or evaluating the sensitivity of ischemic heart disease.

Aged↗
PubMed1996

Somatic cell mutations at the glycophorin A locus in erythrocytes of atomic bomb survivors: implications for radiation carcinogenesis.

To clarify the relationship between somatic cell mutations and radiation exposure, the frequency of hemizygous mutant erythrocytes at the glycophorin A (GPA) locus was measured by flow cytometry for 1,226 heterozygous atomic bomb (A-bomb) survivors in Hiroshima and Nagasaki. For statistical analysis, both GPA mutant frequency and radiation dose were log-transformed to normalize skewed distributions of these variables. The GPA mutant frequency increased slightly but significantly with age at testing and with the number of cigarettes smoked. Also, mutant frequency was significantly higher in males than in females even with adjustment for smoking and was higher in Hiroshima than in Nagasaki. These characteristics of background GPA mutant frequency are qualitatively similar to those of background solid cancer incidence or mortality obtained from previous epidemiological studies of survivors. An analysis of the mutant frequency dose response using a descriptive model showed that the doubling dose is about 1.20 Sv [95% confidence interval (CI): 0.95-1.56], whereas the minimum dose for detecting a significant increase in mutant frequency is about 0.24 Sv (95% CI: 0.041-0.51). No significant effects of sex, city or age at the time of exposure on the dose response were detected. Interestingly, the doubling dose of the GPA mutant frequency was similar to that of solid cancer incidence in A-bomb survivors. This observation is in line with the hypothesis that radiation-induced somatic cell mutations are the major cause of excess cancer risk after radiation exposure. Furthermore, the dose response was significantly higher in persons previously or subsequently diagnosed with cancer than in cancer-free individuals. This may suggest an earlier onset of cancer due to elevated mutant frequency or a higher radiation sensitivity in the cancer group, although the possibility of dosimetry errors should be considered. The findings obtained in the present study suggest that the GPA mutant frequency may reflect the cancer risk among people exposed to radiation.

Adult↗
PubMed1996

[Current state and problems of the development of malaria vaccine].

The development of vaccines against malaria, particularly the one caused by Plasmodium falciparum, is urgently needed to combat drug-resistant parasites, now spreading in most parts of the tropics. This article reviews molecular and immunological studies on potential candidate antigens at both the sexual stages and the asexual stages of the parasite development and several vaccination trials of SPf66, a synthetic vaccine being currently undertaken in the field. The identification of immunodominant T cell and B cell epitopes and antigen polymorphism/antigenic variation in the parasite, which obviously constitute major problems to be solved before producing effective vaccines, are discussed.

Animals↗
PubMed1996

[Changes in plasma level of brain natriuretic peptide during exercise in recovery phase of myocardial infarction and the clinical significance].

Brain natriuretic peptide (BNP) plasma levels increase in patients with myocardial infarction and may reflect the degree of left ventricular dysfunction. The changes in plasma level of BNP during exercise in the recovery phase and the clinical significance were investigated in 60 patients (55 men and 5 women; mean age 62.3 +/- 9.8 years) with initial acute infarction. Cardiopulmonary exercise testing was performed with a treadmill using the ramp protocol in 60 patients in the first month and 46 in the third month after the onset of the disease. Blood samples for measuring BNP and atrial natriuretic peptide (ANP) were obtained in the resting control state and immediately after peak exercise. Plasma BNP in the first month had a significant negative correlation with anaerobic threshold (AT) and peak oxygen uptake (peak VO2), and the serial change in plasma BNP from the first to third month had a significant negative correlation with the serial change of AT (peak: r = -0.35, p < 0.05) and peak VO2 (rest: r = -0.35, p < 0.05; peak: r = -0.45, p < 0.01). The serial change of plasma ANP had no relationships with the serial change of AT or peak VO2. Because the serial change ratio of plasma BNP reflects the serial change of exercise tolerance in the recovery phase of myocardial infarction, we conclude that the serial measurement of plasma BNP level is a useful non-invasive parameter for predicting latent heart failure in patients with myocardial infarction.

Aged↗
PubMed1996

A unique and sensitive ELISA technique for typing ABH antigens in bloodstains using UEA-I lectin--the removal of detergent with a Sephadex G-25 mini-column improves sensitivity.

A unique sandwich enzyme-linked immunosorbent assay (ELISA) for the determination of ABH antigens in bloodstains has been developed. Human anti-A and -B antisera and Ulex europaeus anti-H lectin were coated on the inner surface of microplate wells. The sample antigens from bloodstains, solubilized with n-octyl-beta-D-glucopyranoside which was then removed by passing through a Sephadex G-25 (G-25) mini-column, were placed in the wells. After washing the wells repeatedly, peroxidase-conjugated Ulex europaeus lectin I was added and incubated. Antigen activities were determined by the development of colors using o-phenylenediamine/H2O2. This technique permitted clear detection of all ABH antigens corresponding to the antisera and lectin with high sensitivities. The A and B antigens were solubilized as aggregates with H antigen from the erythrocyte membrane. Excess detergent remaining in the sample reduced the sensitivity and accuracy of this ELISA, probably due to the removal of antibody from the wells by the effect of the surfactant. The treatment of solubilized antigens with G-25, an indispensable step, eliminated the adverse effect of the detergent on the ELISA. The ELISA method reported here was proved to be easy, economical and sensitive, and this technique should be useful in the forensic practice.

ABO Blood-Group System↗
PubMed1996

[Study on expression of proliferating cell nuclear antigen (PCNA) in ovarian cancer].

Specimens of ovarian cancers, which were obtained through laparotomy from 17 patients who received no preoperative chemotherapy and were examined histopathologically, were immunohistologically stained with anti-PCNA antibody to examine the ability to proliferate. The percent age of stained tumor cells per 1,000 cells was used as a PCNA-labeled rate. This rate was analyzed in relation to the clinical stage/histological type and the presence or absence of lymph node metastasis. 1. Tissue specimens were stained with anti-PCNA antibody in all cases, and the PCNA-labeled rate was 49.5 +/- 13.3%. 2. There were no significant differences in PCNA-labeled rates between different histological types or between clinical stages. 3. The PCNA-labeled rates was significantly higher in cases with metastasis than in those without metastasis (p < 0.01). 4. No metastasis was detected in the cases showing a PCNA-labeled rate of 50% or below. It was indicated that this PCNA-labeled rate, which can be determined with formalin-fixed specimens, is useful for evaluating the degree of biological malignancy of ovarian cancer.

Adenocarcinoma, Clear Cell↗