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Biomedical subjects

N Otsuka

Publications and source records attributed to N Otsuka.

At least 91 records · Page 5Linked to original sources
PubMed1990

Iodine-131 uptake in a patient with thyroid cancer and rheumatoid arthritis during acupuncture treatment.

A patient with thyroid carcinoma had abnormal accumulation of I-131 in the areas of both feet and hands on whole body scan. The sites of abnormal accumulation of I-131 were similar to those on bone scintigraphy. The radiographic examination of the lesions showed characteristic findings of rheumatoid arthritis, and the presence of small gold needles for acupuncture treatment was demonstrated. There were no findings of bone metastases. Although the mechanism of accumulation of I-131 in this patient is unknown, interpreters of I-131 whole body scintigraphs should keep this case in mind when acupuncture treatment has been done. The authors can only speculate on a common blood flow mechanism for enhanced HMDP and I-131 uptake in this arthritic patient who had been treated by acupuncture.

Acupuncture Therapy↗
PubMed1990

[Multiple extra-osseous accumulation of 99mTc-phosphorous compounds bone scintigraphy in small cell lung cancer associated with hypercalcemia].

Bone scintigraphy was performed in a patient with lung cancer of small cell. On bone scintigraphy the increased accumulations in kidneys were observed, while no findings of multiple skeletal accumulations suspected of bone metastases were observed. Four weeks later, when hypercalcemia has been advanced, on repeated bone scintigraphy the extra-skeletal accumulations in such as lung, heart and stomach were shown. These findings indicated that the cause of hypercalcemia in this case was due to not bone metastases but humoral hypercalcemia which the osteolytic substance was produced from tumor. In present paper, the usefulness of bone scintigraphy in hypercalcemia with malignancy, and the mechanism of hypercalcemia have been described and discussed.

Bone and Bones↗
PubMed1989

Quantitative electron microscopic analysis of postnatal development of zinc-positive nerve endings in the rat amygdala using Timm's sulphide silver technique.

The distribution and quantitation of zinc during postnatal development of the rat amygdala were investigated by light and electron microscopy with Timm's sulphide silver method. The adult rat amygdala could be divided into basolateral, basomedial, central, cortical, intercalated, lateral and medial subnuclei on the basis of Timm's plus Toluidine blue staining. Only a very weakly positive Timm's reaction could be observed in newborns, and a positive reaction was seen on the 5th postnatal day. The reaction became stronger with development, and reached adult levels by the 30th postnatal day. Electron microscopically, we investigated the basolateral subnucleus of the amygdala. The electron-dense deposits of silver grains from the Timm's reaction were only seen in nerve fibers endings containing many small clear vesicles. The results are similar to those described for mossy fiber endings in the rat hippocampus and in boutons of other telencephalic structures. The number of deposits of silver grains increased with age, and reached that of the adult between the 20th and 30th postnatal days. A significant increase in the number of silver grains per micron 2 area of the Timm's-positive nerve terminals occurred between the 10th and 20th postnatal days. Based on the available literature, these findings suggest that zinc exists in nerve fiber endings in the rat amygdala and that the amount increases with postnatal age. The findings are consistent with an important role for zinc in synaptic transmission.

Aging↗
PubMed1989

Ultrastructural changes in granule cell somata and mossy fibers of the rat hippocampus during picrotoxin-induced convulsions.

Ultrastructural changes in hippocampal granule cells, mossy fibers and mossy fiber boutons were examined following the administration of picrotoxin in adult rats. Generalized seizures occurred within 5-10 min after the intraperitoneal injection of picrotoxin. The electron-microscopic examination of hippocampal tissues from rats that had been perfused with fixative during the seizure revealed that the large dense-core vesicles increased in number and accumulated on the presynaptic membranes of mossy fiber boutons; some of these vesicles appeared to be fused with the membranes, and omega-shaped exocytotic profiles were frequently seen. Furthermore, greatly increased numbers of coated vesicles (60-90 nm in diameter) were observed on the maturing faces of Golgi fields of granule cells. Thus, our study not only indicates an increased incidence of exocytosis of large dense-core vesicles during picrotoxin-induced seizures, but also suggests that these vesicles are replaced in excess from the perikaryon of the granule cell.

Animals↗
PubMed1989

New perspectives for diagnosis of nodular goiter by technetium-thallium subtraction scanning.

To improve the scintigraphic differential diagnosis of thyroid nodules, Tc-99m pertechnetate-Tl-201 Cl subtraction scintigraphy (Tc-Tl subtraction scanning) was performed in 106 patients with various histologically proven thyroid nodules. Results were evaluated by comparison with surgical findings and preoperative ultrasonographic results. Thyroid nodules were more successfully detected by Tc-Tl subtraction scanning than by either Tc-99m pertechnetate or Tl-201 Cl scintigraphy alone. Detection of nodules was further improved when images recorded by the three methods were integrally observed (sensitivity 83%, accuracy 89%), with detectability approaching that of ultrasonography. False-positive or -negative Tc-Tl subtraction scans were obtained principally when multiple nodules were present (7 cases) or when no discrepancy existed between the accumulations of Tc-99m pertechnetate and Tl-201 Cl (18 cases). Most colloid nodules exhibited irregular margins, heterogeneous internal accumulations of Tl-201 Cl, and distorted shapes on Tc-Tl subtraction scans, while the majority of adenoma were oval-shaped with smooth margins. Carcinoma were characterized by homogeneous internal accumulation of Tl-201 Cl and distorted shapes.

Diagnosis, Differential↗
PubMed1989

Ultrastructural study of atrial specific granules in rat atrium after incubation with calcium ionophore (A23187).

The release mechanism of the rat atrial granules containing atrial natriuretic polypeptide (ANP) was examined. In addition, the ultrastructure of right atrial myocardiocytes incubated in a medium containing an excess calcium and calcium ionophores (A 23187) was investigated by electron microscopy. After 3-15 minute incubation in the medium, many ANP-containing atrial specific granules were detected in the vicinity of the subsarcolemmal region, and invagination of the plasma membranes occurred as well as a large number of vacuoles were observed. After incubation with an excess calcium and calcium ionophores for 40 minutes, the atrial specific granules had completely disappeared and numerous vacuoles appeared in the sarcoplasm of the atrial myocardiocytes. Thus, release of ANP and their reabsorption by membranes were accelerated by the presence of calcium and calcium ionophores.

Animals↗
PubMed1989

The thallium-201 time activity curve in thyroid cancer: a role for the detection of metastases.

The Tl-201 Cl time activity curves were evaluated in 17 patients with histologically proven benign nodules and papillary carcinoma of the thyroid gland. In the dynamic studies, the uptake at the region of interest was counted every 10 sec for 20 min after the intravenous injection of 2mCi Tl-201 Cl. The curves from frame 21 to 100 were transformed to linear plots for clinical evaluation. Papillary carcinoma could not be differentiated from benign lesions by means of the values of the washout rate. However, the "relative washout rate" in papillary carcinoma was lower than that of benign lesions (P less than 0.05). Although the average values of the "relative extrapolated uptake" in papillary carcinoma appeared to be greater than those in benign lesions, the difference was not statistically significant. The difference in the washout rates between lymph node metastases and local recurrences, and pulmonary metastases of the papillary carcinoma was significant (P less than 0.05).

Adenoma↗
PubMed1989

[A case of Creutzfeldt-Jakob disease followed up by N-isopropyl-[123I]-p-iodoamphetamine and 99mTc-hexamethylpropyleneamine oxime SPECT].

N-isopropyl-[123I]-p-iodoamphetamine (123I-IMP) and 99mTc-hexamethylpropyleneamine oxime (99mTc-HM-PAO) SPECT were performed in a 66 yrs-old female patient with Creutzfeldt-Jakob disease (CJD). The decreased accumulation of both radiopharmaceuticals, which localized initially in the focal regions and progressed eventually to the whole brain, were observed in the early stage of CJD, when no abnormal findings were obtained on X-CT. Although the redistribution of 123I-IMP was recognized in the relatively early stage in which the accumulation was significantly decreased, it disappeared with the progression of the disease. The accumulation of both radiopharmaceuticals which decreased remarkably in the early stage of CJD was sustained in low level during the chronic stage. The accumulation ratio of 99mTc-HM-PAO, after second examinations, to that on first SPECT was lower than those of 123I-IMP. It was suggested, as this cause, that the difference of the accumulation mechanism of both agents might be concerned. Thus, it is interested to follow up a patient with CJD by using 123I-IMP and 99mTc-HM-PAO SPECT, and this modality will provide a useful information to clarify the pathogenesis of CJD.

Aged↗
PubMed1989

[Single photon emission computed tomography (SPECT) using 99mTc-hexamethyl propyleneamine oxime in patients with ischemic cerebral diseases: comparative study of N-isopropyl-p-[123I]-iodoamphetamine and 99mTc-DTPA SPECT].

In order to confirm the diagnosis and clarify the pathophysiology in the ischemic lesions in brain, 99mTc-PAO SPECT was performed in 42 patients with ischemic cerebral diseases, and the findings on 99mTc-PAO SPECT were compared with those on 123I-IMP or 99mTc-DTPA SPECT, and on X-CT. Furthermore, count ratio of ischemic lesion to normal contralateral region (I/N) was used for the evaluation of the detectability in the lesions on 99mTc-PAO or 123I-IMP SPECT, and less than 0.95 of I/N ratio was defined as the decreased accumulation. The detectability of ischemic lesion in brain with 99mTc-PAO SPECT was 80%, which was superior to that (60%) of LDA on X-CT. Especially, 99mTc-PAO SPECT was useful in cases which were examined early after the onset of the attack. On the other hand, 123I-IMP SPECT showed the best result (88%) in the detectability, and furthermore I/N ratio on 123I-IMP SPECT was lower than that on 99mTc-PAO SPECT. In the delayed phase on 123I-IMP SPECT the redistribution was observed in 30%, while on 99mTc-PAO SPECT it was done in none of them. The accumulation of 99mTc-DTPA in brain was found in 6 of 14 cases (43%), and 2 cases among them also showed the accumulation of 99mTc-PAO in the ischemic lesion. In such cases the destruction of BBB might be considered as the cause of the accumulation of 99mTc-PAO. Thus, 99mTc-PAO SPECT was thought to be useful method in clinical studies of the ischemic cerebral diseases.

Amphetamines↗