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Biomedical subjects

O Ishida

Publications and source records attributed to O Ishida.

At least 91 records · Page 5Linked to original sources

High resolution computed tomography of auditory ossicles.

Auditory ossicular sections were scanned at section thicknesses (mm)/section interspaces (mm) of 1.5/1.5 (61 patients), 1.0/1.0 (13 patients) or 1.5/1.0 (33 patients). At any type of section thickness/interspace, the malleal and incudal structures were observed with almost equal frequency. The region of the incudostapedial joint and each component part of the stapes were shown more frequently at a section interspace of 1.0 mm than at 1.5 mm. The visualization frequency of each auditory ossicular component on two or more serial sections was investigated. At a section thickness/section interspace of 1.5/1.5, the visualization rates were low except for large components such as the head of the malleus and the body of the incus, but at a slice interspace of 1.0 mm, they were high for most components of the auditory ossicles.

Adolescent↗

[MR imaging of orbital tumors].

Nine cases of pathologically confirmed orbital tumors were evaluated with magnetic resonance imaging (MRI) at 0.5T. Seven cases were examined with orbit-coil using 7-mm-thick sections and two cases were examined with head-coil using 10-mm-thick sections. All lesions were clearly demonstrated on T1-weighted images as low intensity. However, the lesions were indistinct on T2-weighted images because of low contrast between the lesions and surrounding orbital fat and artefact produced by eye movement. Two of three cases with meningioma examined with orbit-coil were clearly discriminated from the optic nerve. Meningioma in the remaining case examined with head-coil was discriminated from the optic nerve by administration of Gd-DTPA. Adenoma of the right lacrimal gland was shown as an enlarged gland on T1-weighted images. Pseudotumors (four cases) showed very low intensity on T1-weighted images. Three cases of four pseudotumors showed low intensity on T2-weighted images. Among them one was moderately low intensity, and histological examination of the lesion showed prominent fibrotic changes. Pseudotumor of the remaining case examined with the head-coil showed same intensity with fat on T2-weighted images. Intraorbital infiltrating foci of chronic lymphocytic leukemia showed low intensity with fat on T1-weighted images, and the same intensity with fat on T2-weighted images. MRI may be useful to discriminate pseudotumor with fibrotic changes (chronic inflammatory lesions) from lymphoma or leukemic infiltration.

Adenoma↗

Suppression by cyclosporine of cellular and humoral reactivity after peripheral nerve allografts in mice.

Peripheral nerve allografting has been the subject of many experimental and clinical studies. As yet, however, no successful method has been established. One reason is the lack of detailed studies on the immune response under different conditions. We examined both the cellular and humoral immune responses in fresh sciatic nerve allografts in inbred mice, using a mixed lymphocyte culture reaction and a lymphocyte-mediated cytotoxicity to examine cellular immunity and a complement-dependent cytotoxicity test to examine humoral immunity. Enhanced MLC activity against donor allogenic major histocompatibility complex antigens was demonstrated, and specific cytotoxic T cell activity and the production of specific antigens in serum also were observed. Thus peripheral nerve tissue exhibited potent immunogenicity. We used cyclosporine, an immunosuppressive agent, to suppress the immune response and obtain favorable nerve regeneration. We performed immunologic and histologic studies to establish a causal relationship. Administration of 20 mg of CsA suppressed both the cellular and humoral immune response to levels comparable to those seen in isografting. Histologic examination disclosed favorable regeneration of axons, also comparable to that seen in isografts.

Animals↗

[Effect of the portal vein injection of cisplatin and lipiodol on rat liver].

The purpose of this study was to elucidate the efficacy and safety of cisplatin powder, suspended in lipiodol, as a means for the treatment of liver cancer by injection into the portal vein. The effects of lipiodol (0.1 ml. 0.2 ml. 0.3 ml. 0.4 ml) alone, as well as that of cisplatin powder (1.0 mg) suspended in lipiodol or saline (0.1 ml), on the liver, was investigated by administration of them into the portal vein in 100 normal Wistar rats. The results revealed that the hepatic cells were moderately affected by a small amount of lipiodol alone, but a large amount of lipiodol caused multiple anemic infarctions in the peripheral area of the liver. And, also the injection of cisplatin powder suspended in lipiodol, compared to that suspended in saline, resulted in higher concentration of platinum in the liver. Histologically severe degenerative changes were also perceived in the liver, but these changes were reversible. These results suggest that cisplatin powder suspended in lipiodol is to be used for the treatment of liver cancer.

Animals↗

[A case of renal leiomyoma with remarkable calcification].

A case of renal leiomyoma with remarkable calcification is reported. The patient is a 46-year-old female. The tumor is 9 x 10 x 12 cm in size and is occupied by granular minute calcifications. Angiographically segmental arteries are stretched by a tumor, in which there are minute tumor vessels and inhomogeneous tumor stain.

Calcinosis↗

[A case of retroperitoneal neurinoma].

A case of retroperitoneal neurinoma is reported. The patient was a 34-year-old female without symptoms. CT scan showed a large low density mass, a part of which was enhanced. US showed a lobulated cystic mass. Angiography showed avascular mass and portal vein was shown with displacement and stenosis. Pathological diagnosis was benign retroperitoneal neurinoma (Antoni A and Antoni B).

Adult↗

[Changes in serum parathyroid hormone levels during pregnancy].

As pregnancy poses a significant challenge to maternal calcium homeostasis, it is interesting to investigate a change in serum parathyroid hormone (PTH) level throughout pregnancy. PTH metabolism in pregnancy has not been clearly defined. We have made an attempt to evaluate changes in serum intact PTH level during pregnancy. Compared with nonpregnant women, serum intact PTH concentrations were decreased significantly in pregnant women during the first and the second trimester, but not during the third trimester. Nephrogenous cyclic AMP excretion, index of parathyroid function has been reported to be decreased in pregnant women during the first and second trimester, but to be in normal range in pregnant women during third trimester. Our finding consisted with these facts.

Adult↗

[A case of extramedullary plasmacytoma of the spleen].

A case of extramedullary plasmacytoma of the spleen in a 39 years-old man was reported. The tumor occupied almost of the spleen and extended to the transverse colon. 67Ga scintigraphy and MRI, particularly T 2-weighted image were useful in diagnosis of the localization.

Adult↗

Improved determination of vanadium in biological fluids by electrothermal atomic absorption spectrometry.

We made sensitive and accurate electrothermal atomic absorption spectrometric measurements of vanadium in small volumes of serum. The wet-digested sample was extracted into an organic solvent, with N-benzoyl-N-(o-tolyl)hydroxylamine (BTA) as the chelating reagent. After evaporating the solvent, we dissolved the residue in acetic acid, and injected a 60-microL aliquot into a graphite furnace. In this way we could measure vanadium concentrations as low as 80 ng/L in 4 mL of serum. The within-run CV was 3.3% for serum, 7.7% for urine. Analytical recoveries of vanadium added to serum and urine were 90.3% and 90.8%, respectively. We measured vanadium concentrations in sera from 64 healthy persons (group 1), 15 nondialyzed uremic patients (group 2), and 11 hemodialyzed patients (group 3). The highest concentration of vanadium in group 1 was 240 ng/L; about 60% of the values for this group were less than 80 ng/L. In group 3, the vanadium concentrations were extremely high (15 +/- 14.2 micrograms/L, mean +/- SD), less so (but still above normal) in group 2 (1.58 +/- 3.16 micrograms/L).

Adult↗

[Effect of intra-arterially injected cisplatinum and lipiodol on the rat liver].

The purpose of this study was to elucidate the availability of cis-platinum powder suspended in lipiodol as a means for the treatment of liver cancer. The effects of cis-platinum powder (1.0 mg), suspended in lipiodol or saline (0.1 ml), as well as that of lipiodol (0.1 ml, 0.3 ml) alone, on the liver, was investigated by intra-arterially administration to 72 normal Wistar rats. It was found that injection of Cis-platinum powder suspended in Lipiodol, is compared to the suspension in saline, resulted in higher concentrations of platinum in the liver Severe histological degenerative and necrotic changes were also found. The liver cells were only moderately affected by lipiodol alone, but large amounts of lipiodol multiple anemic infarctions in the peripheral area 24 hours later. These results suggest that cis-platinum itself affects liver cells only slightly and therefore can be used for the treatment of liver cancer.

Animals↗

A computed image analyzing system for quantitation of melanocyte morphology in café-au-lait macules of neurofibromatosis.

Split-dopa preparation is a commonly used technique to visualize the epidermal melanocytes. It can characterize the number of melanocytes and their tyrosinase (dopa-oxidase) activities. There is not, however, any method to quantitate the morphologic changes of dopa-positive melanocytes in the split preparation. This study designed a computed image analyzing system and evaluated the structure of epidermal melanocytes in café-au-lait macules with comparison to normally pigmented skin in 5 patients with neurofibromatosis. By this method we were able to delineate the melanocyte structure with melanocyte population and coloration of the macules. We found that the population and structure of melanocytes differ greatly depending on the coloration of the café-au-lait macules. The light brown and brown macules showed the normal population of melanocytes with an increase in the area and perimeter of whole cell; the area, perimeter, and diameter of cytoplasm; and the area, length, and breadth of dendrites. In contrast, the dark brown macules revealed a significant increase of the epidermal melanocytes with a decrease in all of these parameters. Thus, the methodologic design presented here may enable a quantitative, two-dimensional analysis of melanocyte structure at the light microscopic level in the normal skin and in various pigmentary disorders.

Humans↗

[Evaluation of rIFN-gamma in the treatment of lymphoma and melanoma of the skin by systemic and intralesional administration].

This study evaluated the clinical effect of rIFN-gamma for the treatment of lymphoma and melanoma of the skin by systemic intravenous and intralesional administration. By intravenous drip infusion, one of two cases of mycosis fungoides (stage IV) showed CR of skin lesions by administration of a total of 160 X 10(6) units, 4 or 8 X 10(6) units, every other day for 3 months. The remaining case was, however, in a state of PD. Intralesional administration of rIFN-gamma to six cases of cutaneous lymphoma, including three cases of mycosis fungoides, two cases of cutaneous T cell lymphoma, and one case of adult T cell lymphoma, resulted in three cases of CR, two cases of MR and one case of PD. In contrast, four cases of malignant melanoma, two of which received systemic administration and two intralesional administration, did not show any obvious clinical response, one showing PR and the other three PD. Histopathological examination of skin lesions before and after administration of rIFN-gamma indicated that the cutaneous lymphoma lesions were initially infiltrated by lymphocytes and macrophages, and that later on, they were free from tumor cells. Our study indicates that rIFN-gamma appears to provide a new modality for the treatment of cutaneous lymphoma by systemic and intralesional administration.

Administration, Cutaneous↗