Biomedical subjects
R Nakano
Publications and source records attributed to R Nakano.
Cervical dilatation with pessaries containing a new prostaglandin E1 analogue in patients undergoing induced abortion.
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Cervical ripening with dehydroepiandrosterone sulphate.
Dehydroepiandrosterone sulphate (DHEA-S) was given intravenously twice a week after 38 weeks gestation to ripen the uterine cervix in 20 nulliparae and 24 parous women who subsequently went into labour at term. The condition of the uterine cervix was assessed by Bishop scoring. The increase in the score in nulliparous women given DHEA-S was significantly greater than that in the control group, who were given placebo injections, on the 7th, 14th and 21st days. The increase in the parous women was significant only on the 7th day. In nulliparous women the dilatation, effacement and consistency improved significantly, while in the parous women the effect of DHEA-S was apparent only in the consistency. The duration of labour was significantly shortened by treatment with DHEA-S in nulliparae but this effect was not found in parous women. The interval between the first administration of DHEA-S and the onset of labour in nulliparae was significantly shorter than that in the control group. There were no serious side effects or complications. Our results suggest that DHEA-S may be used safely and effectively to ripen the uterine cervix and to trigger the onset of labour in late pregnancy.
Ovarian morphologic features and endocrine profile in amenorrheic patients.
Ovarian morphologic features and endocrine profile were investigated in 20 patients with primary amenorrhea and 41 patients with secondary amenorrhea. In light of macroscopic and microscopic findings, it was possible to distribute the anovulatory ovaries into the following six main types: (1) polycystic; (2) sclerotic; (3) normotrophied; (4) hypoplastic; (5) atrophic, and (6) streak. Anovulatory ovaries with or without follicles in an early developmental stage, such as the streak or hypoplastic type, were found in patients with primary amenorrhea. In contrast, ovaries with follicles in a late developmental stage, such as the polycystic, sclerotic and normotophied type, were seen in patients with secondary amenorrhea. A close correlation between ovarian morphologic features and hormonal parameters, such as serum FSH and LH levels, and the 24-hour urinary excretion of total estrogens was proved. From the present results, visualization of the ovaries and histologic examination of tissue obtained by biopsy might be an accepted part of the investigation of patients with primary and secondary amenorrhea, particularly those also complaining of infertility. It is no longer justified to postpone investigation until the infertile patients have proved their infertility over several years of a barren, marriage, and ovarian stimulation should be considered at an early stage.
Effects of a new angiotensin-converting enzyme inhibitor, MK 421, in normal men and patients.
Effects of MK 421, a new angiotensin-converting enzyme inhibitor, were studied in normal men and patients. MK 421 was given at 0900 h as a single oral dose of 20 mg, to 5 normal men and 2 patients with essential hypertension and 10 mg to a patient with Bartter's syndrome, in the recumbent position. In all of them blood pressure (BP) fell, plasma angiotensin I (Pl AI) and plasma renin activity (PRA) increased, and plasma aldosterone (PA) decreased from 2 h to 6 h. Maximum effects were observed at 4 or 6 h. Then the effects attenuated gradually but still remained at 24 h. In the same 5 normal men angiotensin I (AI) was infused iv at a rate of 20 ng/kg . min from 0900 h to 1500 h, from 2030 h to 2100 h, and the next morning from 0830 to 0900 h. At first the BP rose and PA increased. The onset of the BP fall was at 35, 55, 60, 70 and 85 min in each subject, respectively. Then the BP and PA began to decrease and the Pl AI and PRA began to increase. The maximum effects were observed at 4 or 6 h. Then these inhibitory effects on the AI were attenuated but still remained at 24 h. The 2 patients with essential hypertension and a patient with malignant hypertension was treated with MK 421 at a daily doses of 5 to 40 mg for 2 to 6 months. They all showed a fall in BP and no side-effects were noted. From these results it is concluded that MK 421 is a strong and long-acting antihypertensive drug and its clinical application seems very useful for the treatment of hypertension.
Biological activity of des-asp1-des-arg2-angiotensin II in man.
The biological activity of des-asp1-des-arg2-angiotensin II (3-8AII) was studied in man. When 3-8AII was infused iv at rates of 22 and 308 pmol (17.5 and 250 ng)/kg . min separately into 5 normal men each for 120 min, blood pressure showed no change, plasma renin activity (PRA) decreased gradually and plasma aldosterone showed a gradual slight increase. The lower dose of 3-8AII partially inhibited captopril-induced PRA increase and plasma aldosterone decrease in the same 5 normal men and the higher dose of the hexapeptide completely abolished them. In one of the 5 normal men blood pressure rose in response to doses of 3-8AII greater than 2220 pmol (1750 ng)/kg . min. When 3-8AII was infused iv at 308 pmol/kg . min into 2 patients with Bartter's syndrome for 60 min, it caused marked decrease in PRA and plasma aldosterone but no change in blood pressure. This decrease in plasma aldosterone is thought to be secondary to the decrease in PRA. From these results it is evident that 3-8AII has a minimal pressor action, a weak aldosterone-stimulating action and a significant renin-suppressing action in man and this PRA-lowering action is thought to be due to direct inhibition of renin release by its whole molecule or a smaller part of the molecule.
[LH receptor binding inhibitor (LHRBI) (author's transl)].
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[Biosynthetic system of angiotensins and aldosterone].
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Pituitary and ovarian response to luteinizing hormone releasing factor in normal and sulpiride-induced hyperprolactinemic women.
Five Japanese women with regular menstrual cycles (control group) and 5 sulpiride-induced hyperprolactinemic women (sulpiride group) were given a 100-microgram synthetic luteinizing hormone releasing factor (LRF) intravenously, on the 20th day of the menstrual cycle and on the 10th day of the next cycle. The mean responses of luteinizing hormone and follicle-stimulating hormone to LRF in the sulpiride group were higher than those in the controls. Despite enhancement of the gonadotropin levels, the mean response of estradiol was suppressed significantly in the sulpiride group in the luteal and follicular phase of the menstrual cycle. However, the mean response of progesterone was not statistically different, in either group, in the luteal phase. The results suggest that sulpiride-induced hyperprolactinemia exerts an inhibitory effect on steroidogenic activity in estradiol but not in progesterone in the ovary.
[Case of congenital pelvic arteriovenous malformation].
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Use of the vacuum extractor for delivery of the fetal head at cesarean section.
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Suppression of human chorionic gonadotropin by progestational steroids.
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Abdominal radical hysterectomy and bilateral pelvic lymph node dissections for cancer of the cervix. The Okabayashi operation its modifications.
The original Wertheim operation for cancer of the cervix has been modified by Latzko, Okabayashi, Meigs and other gynecologist. The modified methods are called the extended Wertheim methods or the Latzko-Okabayashi-Meigs operation. Although the sequence of the operative steps differs, the Latzko and the Okabayashi operations are similar in the exposure of the spaces between the three main sections of taut connective tissue which supports the organs of the small pelvis. By contrast, both methods differ in the divisions of the superficial and deep layers of the vesicouterine ligament. The procedure for resection of the vesicouterine ligament described by Okabayashi, especially for complete separation of the deep layer of the ligament, enables to perform an extensive resection of the vesicouterine ligament and the lateral paravaginal tissue and to transect the vagina sufficiently at the required level as far as necessary. The present paper describes the original and modified Okabayashi operation in comparison with the extended Wertheim methods by Latzko and Meigs.
Evidence for a role of endogenous estrogen on follicular growth in immature female rats.
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Effects of oestrogen and prostaglandin F2 alpha on luteinizing hormone receptors in human corpora lutea.
The binding of 125I-labelled human LH (hLH) to the 2000 g subcellular fraction of human corpora lutea of the menstrual cycle was examined. Displacement studies demonstrated that 125I-labelled hLH was specifically bound in the 2000 g fraction of human luteal tissue. Specific binding of 125I-labelled hLH was demonstrated in all the corpora lutea examined except for two aged corpora lutea at an early proliferative phase of the cycle. The number of binding sites for hLH increased between the early to mid-luteal phase and decreased towards the late luteal phase. However, the apparent dissociation constant (Kd) in each corpus luteum did not vary throughout the menstrual cycle. In addition, the effects of treatment with diethylstilboestrol diphosphate (DES) and prostaglandin F2 alpha (PGF2 alpha) on the binding of 125I-labelled hLH to the 2000 g fraction of luteal tissue were investigated and the changes in hLH receptors were estimated by Scatchard analysis. The number of binding sites were 1.59 x 10(-14) mol/mg protein in control tissue, 0.86 x 10(-14) mol/mg protein in DES-treated luteal tissue and 2.95 x 10(-14) mol/mg protein in PGF2 alpha-treated luteal tissue. Thus, the binding sites for hLH decreased as a result of treatment with DES and increased by treatment with PGF2 alpha. In contrast, the apparent Kd in each luteal tissue revealed almost the same value (4.24 x 10(-10) mol/1) after treatment with DES or PGF2 alpha. The results of the present study suggest that oestrogen and prostaglandin might have an important role in modulating hLH receptor in human corpora lutea.
[LH receptor and modulation of luteal function (author's transl)].
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Increased risk of malignant transformation of hydatidiform moles in older gravidas: a cytogenetic study.
Cytogenetic studies were performed in 35 cases of complete hydatidiform mole, and the results were correlated with maternal age and other clinical parameters. The rate of occurrence of aneuploid cells in the 18- to 39-year age group was 19% of the total cells; the rate in the 43- to 52-year age group was 25%. The rate of aneuploid cells between 2n and 3n was 20% in the latter group but only 7% in the former group. Aneuploid cells were not found in normal villi but were found to predominate in invasive mole and choriocarcinoma. These results suggest that hydatidiform mole may have a greater potential for malignant transformation in patients 40 years and older than in younger patients.
[A radioreceptor assay for catecholamines. II. A study with 4-(2-iodoethyl) pyrocatechol (author's transl)].
We have already reported on a radioreceptor assay for catecholamines utilizing the microsome fraction of bovine myocardium as a catecholamine (CA) receptor and 3H-norepinephrine as a labelled CA. In order to increase the sensitivity of the radioreceptor assay, we used 4-(2-iodoethyl) pyrocatechol (125I-CA) as a ligand instead of 3H-norepinephrine and performed a radioreceptor assay for CA. The following results were obtained: 1) 125I-CA was able to bind alpha-receptors prepared from bovine myocardium. 2) The optimal amount of the microsomal fraction was 250 micrograms/tube, when 125I-CA of 50,000 c.p.m. was used. The appropriate conditions for incubation were 90 minutes at 20 degrees C in a pH 7.0 sucrose solution. 3) By this method utilizing 125I-CA, norepinephrine was detectable in a range from 500 pg to 10 ng/tube. 4) Various compounds with a catechol nucleus showed cross-reaction in this radioreceptor assay system. 5) Whereas beta-adrenergic blocking agents did not inhibit the binding of 125I-CA, phentolamine, a short acting type of alpha-adrenergic blocking agents, was effective in inhibiting the binding. However, dibenamine and phenoxybenzamine, long acting types of alpha-adrenergic blocking agents, increased the binding of 125I-CA to the microsomal fraction. 6) Utilizing this phenomenon, norepinephrine was detectable in the range from 100 pg to 5 ng/tube.