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M Ojima

Publications and source records attributed to M Ojima.

16 recordsLinked to original sources
PubMed1979

[In vivo and in vitro studies on 18-hydroxy-11-deoxycorticosterone and 18-hydroxycorticosterone in normal subjects and in those with various adrenocortical disorders (author's transl)].

Simultaneous measurement of 18-hydroxy-11-deoxycorticosterone (18-OH-DOC) and 18-hydroxycorticosterone (18-OH-B) in the peripheral plasma was carried out on normal subjects and in patients with adrenocortical disorders. The mean plasma levels of 18-OH-DOC at 0800h in normal males and in the follicular and luteal phases of normal females were 8.2 +/- 3.9 ng/100 ml (Mean +/- SD), 7.8 +/- 2.6 ng/100ml and 11.5 +/- 2.8 ng/100ml, respectively. The corresponding levels of 18-OH-B in normal males and in the follicular and luteal phases of normal females were 10.3 +/- 4.2 ng/100ml, 12.4 +/- 4.5 ng/100ml and 13.8 +/- 4.1 ng/100ml, respectively. No differences between the sexes nor the phases of the menstrual cycle were confirmed. ACTH stimulation increased plasma concentrations of 18-OH-DOC and 18-OH-B by 5.1 and 4.4 times respectively, while dexamethasone markedly decreased these 2 steroids. An upright posture increased these steroids significantly. In patients with Cushing syndrome, plasma levels of these 2 steroids were rarely high in cases with adrenocortical hyperplasia and adrenocortical carcinoma, while they were usually within the normal range in adrenocortical adenoma. These 2 steroid levels were increased in primary aldosteronism, idiopathic hyperaldosteronism and congenital 17 alpha-hydroxylase deficiency. They were decreased in Addison's disease and the salt-loosing type of congenital 21 alpha-hydroxylase deficiency. Patients with congenital 21 alpha-hydroxylase deficiency (simple form) showed elevated levels of 18-OH-DOC and normal levels of 18-OH-B. In vitro production of 18-OH-DOC and 18-OH-B was studied by tissue slices of the normal adrenal cortex, adrenocortical carcinoma causing Cushing syndrome, aldosteronoma and nodular hyperplasia with hyperaldosteronism. In the normal adrenal cortex, the mean production rates of 18-OH-DOC and 18-OH-B were 31 and 26 ng/g tissue/hr, respectively. ACTH and angiotensin II significantly increased the production of both 18-OH-DOC and 18-OH-B. In adrenocortical carcinoma, the production of these steroids was markedly diminished and not stimulated with either ACTH or angiotensin II. Aldosteronoma tissue produced these 2 steroids 20 to 40 times that of the normal adrenal tissue and was significantly increased with the addition of ACTH and angiotensin II. Nodular hyperplasia with hyperaldosteronism produced much 18-OH-DOC and 18-OH-B, but did not respond to ACTH and angiotensin II.

18-Hydroxycorticosterone↗
PubMed1979

Bronchogenic carcinoma producing ectopic steroid hormones.

A patient with steroid hormones or androgen producing bronchogenic adenocarcinoma was presented. Clinically he had a mediastinal mass and bilateral multiple pulmonary nodules which showed a rapid growth despite cancer chemotherapy. At postmortem examination, radioimmunoassay of the tumor tissue revealed androgen and their precursors. The mitochondria of the tumor cells resembled those of cells in the zona reticularis of the adrenal cortex.

Adult↗
PubMed1978

Simultaneous determination of plasma 11-deoxycorticosterone, 18-hydroxy-11-deoxycorticosterone, and aldosterone in man.

A method for simultaneous measurement of 11-deoxycorticosterone (DOC), 18-hydroxy-11-deoxycorticosterone (18-OH-DOC) and aldosterone using 1.0-2.0 ml of plasma has been developed. The present method consists of extracting plasma with dichloromethane, separating the DOC, 18-OH-DOC, and aldosterone from other steroids on a Sephadex LH-20 column, and quantitating each steroid by radioimmunoassay. This method was demonstrated to be sensitive, accurate and precise. In 20 normal male subjects, the mean recumbent level of DOC was 9.1 +/- 3.1 ng/100 ml, on random diet, at 0800 h. The corresponding levels of 18-OH-DOC and aldosterone were 8.2 +/- 3.9 ng/100 ml, and 6.7 +/- 2.6 ng/100 ml, respectively. Plasma levels of these three steroids were measured in several types of adrenocortical disorders associated with hypertension and hypokalemia. Patients with Cushing's syndrome due to adrenocortical hyperplasia, and 17alpha-hydroxylase deficiency had elevated DOC and 18-OH-DOC levels, but showed normal or lower aldosterone levels. Hypersecretion of DOC and 18-OH-DOC may cause the symptoms of hypertension and hypokalemia. Patients with primary aldosteronism had elevated levels of DOC and 18-OH-DOC as well as aldosterone. The former two steroids may be hyperproduced as a precursor of aldosterone.

18-Hydroxydesoxycorticosterone↗
PubMed1976

Differences in autonomity of growth hormone secretion in patients with acromegaly.

Thirteen patients with acromegaly were subjected to the examination of autonomity in growth hormone (GH) secretion. TRH (500 mug iv), arginine (0.5 g/kg of body weight iv infusion), LH-RH (100 mug iv) and L-dopa (500 mg orally) were administered, and plasma GH was measured. Among them, 11 patients showed some response in plasma GH to at least one agent, but the other 2 cases showed no response to any of the above 4 agents. In the former 11 cases, the patients were regarded as belonging to the less autonomous type and in the latter 2, to the more autonomous type in GH secretion. Six cases (4 cases of the less autonomous and 2 cases of the more autonomous type) received an administration of 500 mug of synthetic somatostatin parenterally. Following administration of somatostatin, the patients of both types showed significant GH decrease, although GH decrease in the more autonomous type was smaller than that of the less autonomous type. These results would suggest that there might be no acromegalics secreting GH FROM THE PITUITARY WITH COMPLETE AUTONOMITY, AND THE DIFFERENCE OF AUTONOMITY IN ACROMEGALIC PATIENTS MIGHT DEPEND EITHER ON THE DIFFERENCE IN SENSITIVITY AND/OR THE NUMBER OF RECEPTORS IN THE PITUITARY RATHER THAN THOSE IN HYPOTHALAMUS TO EXOGENOUS STIMULI.

Acromegaly↗
PubMed1976

Responsiveness of growth hormone release in acromegalics after irradiation or hypophysectomy.

Effects of X-ray irradiation to the pituitary and transfrontal hypophysectomy were evaluated on the responsiveness of plasma growth hormone (GH) to exogenous stimuli in 8 patients with acromegaly. As exogenous stimuli, arginine, TRH, LH-RH and L-dopa were administered. In 2 out of 3 patients treated with Liniac irradiation, the responsiveness to arginine was essentially unchanged, while in the third patient positive response to arginine disappeared after therapy. Of 2 patients who received a combination of hypophysectomy and Liniac irradiation, the responsiveness to arginine, TRH, LH-RH and L-dopa did not change in 1 patient, but in the other it was observed that negative response to L-dopa became positive after the treatment, remaining the unchanged responsiveness to arginine, TRH, and LH-RH. In 3 hypophysectomized patients, little change in responses to the above 4 stimuli was observed. In summary, out of 22 pairs of responses (pre- and post-therapy) examined 20 were not altered. In 11 pairs of responses (pre- and post-irradiation) particularly, 10 were essentially unchanged. It might be concluded that the responsiveness of GH to exogenous stimuli in acromegalics would not be affected by irradiation or transfrontal hypophysectomy.

Acromegaly↗
PubMed1975

Treatment of Cushing's disease with reserpine and pituitary irradiation.

Eighteen patients with Cushing's disease were treated with reserpine and pituitary irradiation. Complete remission was obtained in 9 out of 18 patients after reserpine treatment of 1-2 mg per day for a mean period of 20.4 months, and pituitary irradiation with a mean of 5,865 rads. In another 9 patients, reserpine 0.8-2 mg per day for a mean period of 22.5 months, and pituitary irradiation with a mean of 6,650 rads, were employed. Of these 9 patients, an additional subtotal adrenalectomy was carried out in 6 patients who are now in complete remission. Because of severe psychic symptoms resulted from the original disease in 2 of the remaining 3 patients, subtotal adrenalectomy was performed first and pituitary irradiation and reserpine treatment followed. Remission was eventually obtained in these 2 cases. One patient refused the operation, and thus had little clinical remission. All of the 17 cases in remission were followed up for periods of 6 months to 10 yr. During this time, only one case which had responded to reserpine and pituitary irradiation relapsed, but regained remission following resumption of therapy. Another died of cerebral glioblastoma 4 yr after remission of the disease. It was noteworthy that endocrinologic data including: plasma levels of ACTH and 11-OHCS, suppressibility by dexamethasone, responses of plasma GH to arginine and to insulin loads, and diurnal rhythm of plasma 11-OHCS were nearly normal in a considerable number of the cases in remission. Effectiveness of the combined therapy with reserpine and pituitary irradiation for treating Cushing's disease may support a working hypothesis that reserpine acts through some as yet unknown mechanism to correct a presumed central nervous disorder, while suitable pituitary irradiation probably corrects the pituitary dysfunction directly.

Adrenalectomy↗