Search PubMed⌕ Search

Biomedical subjects

M Ohata

Publications and source records attributed to M Ohata.

At least 163 records · Page 9Linked to original sources

A radioimmunoassay for rat serum parathyroid hormone using N-terminal of PTH.

Partially purified bovine parathyroid hormone (PTH) produced two kinds of antisera, GP-100 reacting with 125I-labeled bovine PTH (b-PTH 1-84) alone and GP-M reacting with 125I-labeled synthetic N-terminal portion of bovine PTH (b-PTH 1-34) as well as b-PTH 1-84. Rat serum PTH reacted with the latter but not in the former, suggesting a similarity to b-PTH 1-34. Rat serum PTH became undetectable after parathyroidectomy, and increased after Na2-EDTA injection and following renal injury with sodium sulfacetylthiazole.

Animals↗

Differential hydrolysis of bovine parathyroid hormone and its N-terminal peptide by rat kidney.

Highly purified bovine parathyroid hormone (b-PTH 1-84) and its synthetic N-terminal peptide (b-PTH 1-34) were labelled with 125-I and incubated with rat kidney homogenate at 37 degrees C for 1 hour to assess the degree of hydrolysis of the iodinated peptides through measurement of the increase of trichloroacetic acid soluble 125-I fraction. Rat kidney homogenate rapidly hydrolyzed b-PTH 1-84 but was scarcely effective in hydrolyzing b-PTH 1-34. When 125-I labelled b-PTH 1-84 and b-PTH 1-34 were injected intravenously in rats, hydrolysis in vivo of the former appeared to be much more rapid than that of the latter, as shown by the faster disappearance from plasma of trichloroacetic acid precipitable fraction. Incubation of b-PTH (1-84) with rat kidney homogenate caused a shift of 125-I PTH peak almost to the position of salt peak, while the position of 125-I b-PTH (1-34) was almost unchanged by incubation with rat kidney homogenate. N-terminal peptide of bovine parathyroid hormone thus appears to be less susceptible to hydrolytic degradation by rat tissue than the intact hormone, with resultant longer retention in the blood stream.

Animals↗

Epidermoid tumor in the lateral ventricle. Significance of echo-encephalography.

The authors report on a case of epidermoid tumor in the lateral cerebral ventricle. Epidermoid tumors are relatively uncommon intracranial lesions and were first described by Esmarch. Till now about 300 cases have been reported. In Japan this tumor was first described by Yamamura, and since then many cases have been reported. But the one situated in the lateral ventricle has not been reported yet in this country. The significance of echo-encephalography is discussed because this procedure was very useful in determining the location and the nature of the tumor of this case.

Adult↗

Radioisotope scanning for the spinal cord tumor.

Radioisotope scanning with 99mTc-pertechnetate or 67Ga-citrate for the spinal cord tumors was reported. Six patients with spinal cord tumors including 2 ependymomas, 1 neurinoma, 1 metastatic medulloblastoma, 1 metastatic astrocytoma, and 1 metastatic pinealoma as well as 6 patients with non-neoplastic lesions were examined with this method. Two out of 6 cases with tumors showed positive scans and two equivocal scans. This new method is different from myeloscintigraphy and radioisotope angiography as already reported. It directly demonstrates tumor itself like brain scanning and is very useful as nontraumatic method for screening spinal cord lesions, especially in poor risk patient. The usefulness and limitation of this method are discussed.

Adult↗

[Pneumothorax].

Explore the source record for details and available documents.

Adult↗

[Rupture of intracranial aneurysm due to cerebral angiography (author's transl)].

The authors report a case of rupture of intracranial aneurysm by angiography which was done four hours after the subarachnoid hemorrhage. Case; A thirty-one year old male patient was brought to our outpatient's clinic by ambulance because of conscious loss and convulsive seizure on Feb. 5th, 1974. Lumbar puncture showed grossly hemorrhage in the CSF. Immediately he was hospitalized and administered anticonvulsants, hypotensive drugs, antibrinolytic agents and corticosteroid. His signs and symptoms on admission were mild headache, nausea, nuchal rigidity, anisocoria (right greater than left) and left hyper reflexia. This attach was his second. (He first noted the bleeding attack on January 30, 1974). Four hours after this attack cerebral angiography was done under local anesthesia with heavy premedication. Puncture of common carotid arteries were uneventful. Three injections of 60% Conray, at the dose of 8 ml each, were performed and three films were taken. Few minutes after injections, he suddenly became unconscious and ceased respiration for a few seconds. Blood pressure was 210 mmHg at systolic, although 120 mmHg two minutes before. Immediately resuscitation started. His respiration reappeared within 0.5 minute and his vital signs gradually improved. We stopped examination. When returned to his bed, right pupil dilated and optic fundi showed bleeding bilaterally. Arteriography showed a large dumbbell shaped aneurysm at the trification of the right middle cerebral artery but no finding of hematoma (Fig. 1). We decided emergency operation at once. When started the operation his both sides pupil dilated, B.P. was very low. OPERATION: Right side large frontolateral craniectomy was done. Large subdural hematoma (Fig. 2), severe diffuse subarachnoid hemorrhage (Fig. 3) and intracerebral hematoma were found. Aneurysmal neck clipping was successfully done. POSTOPERATIVE COURSE: His level of consciousness was semicomatous. But gradually his state deteriorated and died one week after the operation. AUTOPSY: There was severe edema in both sides cerebrum. The brain stem, especially interbrain, and pons, had fallen into softening, so called respirator brain. This complication of angiography is very rare. This case is the 24th reported case of the ruptured aneurysm by angiography.

Cerebral Angiography↗

[Brain scanning of the posterior fossa tumors (author's transl)].

It has been generally accepted that the scanning of the posterior fossa yield less accuracy in comparison with that of the supratentorial region. It seems that the difficulties are primarily attributable to the parotid gland, the overlying venous sinuses, and the heavy investment of the muscles with their rich vascular supply at the posterior fossa. These problems are compounded by poor patient positioning in the posterior view. We believe that the brain scanning of the posterior fossa is, however, nearly as successful as that of the supratentorial region, when the following procedures are carried out. We performed 99mTc-pertechnetate brain scanning 41 times and 169 Yb-DTPA cisternography 7 times on 25 posterior fossa tumors, from August 1970 to September, 1974. The diagnosis of these cases were confirmed by operation or autopsy. These include six neurinomas, six astrocytomas, three medulloblastomas, three hemangioblastomas, three metastatic tumors, one meningioma, one arteriovenous malformation, one osteochondroma and one microglioma.

Adolescent↗