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Biomedical subjects

M Kanazawa

Publications and source records attributed to M Kanazawa.

At least 289 records · Page 16Linked to original sources
PubMed1983

Assessment of the magnitude of aortic regurgitation by dye injection into the descending aorta.

A technique simpler than the angiographic method for estimating aortic regurgitant volume was tried with 31 patients with aortic insufficiency. During cardiac catheterization, we injected dye into the descending aorta while recording the dye dilution curve in the left ear. The distance between the aortic arch and the tip of the catheter at the lowest point from which the injected dye could be detected in the left ear was rated in terms of the number of corresponding vertebral bodies. This "distance score" closely correlated with the regurgitant stroke volume and with the fraction to total stroke volume, which were measured by angiocardiography (r = 0.927, p less than 0.001; and r = 0.900, p less than 0.001, respectively). The correlation coefficients of the aortographic grade to those parameters were not as high as they were in the relationship of the score to the same parameters. Therefore, these results indicate that the "distance score" is a practical method for assessing the magnitude of aortic regurgitant volume.

Adolescent↗
PubMed1983

The effect of pericardium on the end-systolic pressure-segment length relationship in canine left ventricle in acute volume overload.

The effect of the pericardium on the end-systolic pressure-segment length relationship in the left ventricle was examined with an ultrasonic miniature gauge in open-chest dogs. In 12 dogs, blood was infused until left ventricular (LV) end-diastolic pressure reached about 20 mm Hg, and then the pericardium was opened widely. In the other 12 dogs a pericardiectomy was performed without blood infusion. Stroke volume was measured in six dogs in the former group and in seven dogs in the latter group. After blood infusion, LV systolic, end-systolic, and end-diastolic pressures increased from 120 +/- 14 to 162 +/- 16 mm Hg (mean +/- SD), from 106 +/- 13 to 146 +/- 17 mm Hg, and from 8 +/- 2 to 19 +/- 2 mm Hg, respectively (all p less than .01). End-systolic and end-diastolic segment lengths increased from 8.9 +/- 2.1 to 10.6 +/- 2.2 mm and from 11.6 +/- 2.5 to 14.9 +/- 2.7 mm, respectively (both p less than .01). After pericardiectomy, the segments were further lengthened by 8.9 +/- 4.4% and by 10.0 +/- 6.2%, respectively (both p less than .01). Heart rate, LV systolic and end-systolic pressures, and peak positive dp/dt did not change, although end-diastolic pressure fell from 19 +/- 2 to 18 +/- 2 mm Hg (p less than .01). Stroke volume rose from 13.1 +/- 3.7 to 23.9 +/- 5.0 ml due to volume loading and further increased by 26.7 +/- 9.0% after pericardiectomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1982

The effect of pericardium on the diastolic properties of the heart--experimental studies on volume load and on acute ischemia in open chest dogs.

We studied the effect of the pericardium on the end-diastolic pressure-segment length (P-L) relation in volume loading (Experiment I) and in acute ischemia (Experiment II). Experiment I: In 6 open chest dogs, segment length of left and right ventricles were measured using ultrasonic crystals during blood infusion. Drawing end-diastolic pressure (P, on ordinate) against segment length (L, on abscissa), the P-L curve with pericardium positioned upward compared to that without pericardium. The slopes (b) of the exponential curve (P = aebL) with pericardium were steeper than those without pericardium in both ventricles. The difference between the slopes with and without pericardium was significantly larger in the right ventricle (RV, 0.30 +/- 0.10, mean +/- SEM) than in the left ventricle (LV, 0.05 +/- 0.02, p less than 0.05). These results show that the pericardium inhibits the distensibility of the free wall more in RV than in LV, and enhances a mechanical coupling of both ventricles during volume over-load. Experiment II: In 8 open chest dogs, segment lengths of ischemic and non-ischemic regions in LV were measured after left circumflex coronary occlusion. When the segment lengths and LV pressure became stable, a pericardiectomy was performed. After the pericardiectomy, whereas heart rate and LV systolic pressure did not change, end-diastolic segment length in the ischemic region further lengthened (12.0 +/- 0.2 to 12.5 +/- 0.2 mm, p less than 0.01) and that in the non-ischemic region did not change despite the concomitant fall in LV end-diastolic pressure (EDP, 11.9 +/- 0.6 to 9.8 +/- 0.6 mmHg, p less than 0.01). These results suggest that the pericardium alters the LV end-diastolic pressure-volume relation and is one of the factors contributing to an increase in LVEDP during acute ischemia.

Animals↗
PubMed1982

[Luteotropic effect of human chorionic gonadotropin on human corpus luteum in early gestation (author's transl)].

To study the luteotropic effect of human chorionic gonadotropin (hCG) on human corpus luteum in early gestation, serum pregnenolone, 17 alpha OH-pregnenolone, dehydroepiandrosterone, progesterone, 17 alpha OH-progesterone, androstenedione, 20 alpha-dihydroprogesterone and estradiol levels in both ovarian and peripheral venous blood measured by RIA before and after administration of hCG. Seven patients selected for this experiment were 6 to 16 weeks of gestation complicated with fibromyoma. On hysterectomy, 1,000 or 2,000 I.U. of hCG was directly injected into the ovary with corpus luteum to the patients of 6, 12 and 16 weeks of gestation, or 100,000 I.U. of hCG was infused intravenously to the patients of 9 and 14 weeks of gestation. Before 12 weeks of gestation, all free steroid levels except for conjugated steroids in ovarian vein increased promptly 1.8 to 8.9 fold as compared with control levels and stayed high levels for 25 to 60 minutes after administration of hCG. However no marked alteration of these steroids was observed in peripheral vein. In cases studied after 14 weeks of gestation, no marked change of steroid levels in ovarian vein was noticed, while a moderate increase of hCG was observed. These results demonstrated that hCG stimulates the steroidogenesis of corpus luteum in early pregnancy. It was demonstrated that extremely high doses of hCG was required to stimulate steroidogenesis corpus in luteum gravidarum of early gestation.

Chorionic Gonadotropin↗
PubMed1982

[A study of apocrine resembled metaplasia of endometrium in the patient with functional uterine bleeding and their hormone levels (author's transl)].

Relationship between endometrial findings and serum hormone concentrations in patients with functional uterine bleeding (FUB) was not clarified yet. One hundred patients affected by FUB were divided into four groups according to their endometrial patterns: 1) proliferative phase(P), 2) secretary phase(S), 3) atrophic secretary phase(A-S) and 4) cystic glandular hyperplasia(C). Serum hormone levels which included LH, FSH, prolactine(PRL), estradiol and progesterone were measured by radioimmunoassay. 79% of the patients we studied were between 21 to 45 years and 21% were under 20 years or over 46 years of age. None of the patients received hormone therapy prior to the study. P(45%) and S(30%) were frequently encountered in histological manifestation of FUB while C was found no more than 4%. In 21% of the patients revealed apocrine resembled metaplasia of endometrium(AP), the cells resembled to the epithelium of apocrine sweat glands. This metaplasia was found in every endometrial patterns, but was seen in A-S most frequently. Serum concentrations of hormones in patients classified as C were characteristically and inclined to be hypergonadotropic and hypoestrogenic. High PRL levels were found in group S. All hormone levels except for FSH were statistically lower in the group of AP than that in groups where no AP was found.

Adolescent↗
PubMed1982

[Relation between endocrine changes and bodily development before and after the menarche].

Serum concentrations of sex hormones which including FSH, LH, prolactin (PRL), estradiol (E2), 17 alpha-hydroxyprogesterone (17OH-P4) and 17 alpha-hydroxypregnenolone (17OH-P5) were measured in 233 girls aged 6 to 17. For the longitudinal study, 31 girls aged 10 to 13 were selected and studied for two years to find out the relationship between hormonal changes and pelvic development. The subjects were divided into three groups: Group I; premenarchal girls, Group II; menarche occurred during the studied year, Group III; menarche had already occurred. 1) Changes of hormones with age: FSH and E2 concentrations started to increase from age 10 and LH increased from age 11. On the other hand, PRL concentration decreased from age 10 to 11 in menarchal girls. 2) Changes of hormones for 2 years: The elevation of FSH, LH, E2, 17OH-P4, DHA and 17OH-P5 was noticed in group I. A significant increase of E2 levels in group I and II was noted. On the other hand, concentrations of PRL in group II significantly decreased. 3) Physical development for 2 years: A significant elevation of physical development and outer dimensions of pelves in all groups was observed. However, increase of pelvic indices were significant in group II. 4) Relation between physical development and hormones: Except for PRL all the hormones increased before the onset of menarche and the continuous elevation of E2 was found with increasing age after menarche. These results suggested the possible role of E2 on pelvic development during puberty.

Adolescent↗
PubMed1981

Responses of serum levels of testicular steroid hormones to hCG stimulation in patients with prostatic cancer and benign prostatic hypertrophy.

Serum levels of testosterone (T), dihydrotestosterone (DHT), androsterone (A), 5 alpha-androstane-3 alpha, 17 beta-diol (5 alpha-diol) and estradiol-17 beta (E2) were measured by radioimmunoassay in the sera of 9 patients with untreated prostatic cancer and in 11 with benign prostatic hypertrophy (BPH). Basal levels and responses to hCG stimulation were investigated. Although no specific changes in steroid hormone levels in either disease group were found, response patterns of serum T, DHT, and E2 were shown to be those characteristic of male senescence, suggesting a relative predominance of estrogens over androgens. Neither 5 alpha-diol nor A exhibited appreciable responses to hCG stimulation in our study.

Aged↗
PubMed1980

Cineventriculographic analysis of left ventricular dynamics during sustained handgrip exercise.

In order to evaluate the effect of handgrip on left ventricular dynamics, cineventriculography was performed in 16 patients with heart disease and 5 normal subjects at 30% of maximal voluntary contraction. No patient had ventriculographic evidence of asynergy or valve regurgitation. During exercise, left-ventricular end-diastolic volume (LVEDV) insignificantly increased, left ventricular end-systolic volume (LVESV) decreased, and hence stroke volume (SV) and ejection fraction (EF) rose in the normal group, while in the patient group a similar change in LVEDV was associated with increased LVESV, resulting in unchanged SV and decreased EF. It is notable that during exercise LVEDV increased in both groups, despite a shortened diastolic filling period. Mean velocity of fiber shortening (mean VCF) increased in the normal group and remained unchanged in the patient group. The changes in mean VCF during exercise were correlated with the alterations in SV and EF (r=0.46, p less than 0.05 and r=0.90, p less than 0.001), respectively). These data signify that an increased afterload induced by handgrip leads to an enhanced left ventricular myocardial contraction in addition to an increase in preload in the normal group, while the Frank-Starling mechanism is mainly utilized in the patient group.

Adolescent↗