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T Okayasu

Publications and source records attributed to T Okayasu.

At least 19 recordsLinked to original sources
PubMed1992

Inherited copper toxicity in Long-Evans cinnamon rats exhibiting spontaneous hepatitis: a model of Wilson's disease.

The copper concentrations in organs of developing Long-Evans Cinnamon (LEC) rats (2 d to 13 mo) were measured to elucidate the pathogenesis of their hereditary hepatitis. Hepatic copper contents of LEC rats were significantly higher than those of control rats (26 to 92 times higher). The subcellular distribution of hepatic copper indicated that the nuclear and large granular fractions had been saturated and the cytosol fraction contained about 70% of all the hepatic copper in LEC rats. The serum concentrations of copper and ceruloplasmin were significantly lower than those of control rats from the 4th wk (10-12% and 5-19%, respectively). Copper contents in kidney of LEC rats did not exhibit an increase over those of control rats until 12 wk, but then increased to nearly 40 times higher during fulminant hepatic failure. Accumulation of copper was not detected in the brain or small intestines of LEC rats until 13 mo. The hepatic copper concentration, its subcellular distribution, and serum copper concentration of F1 rats (LEC x Long-Evans Agouti) exhibited the same levels as those of Long-Evans Agouti rats. In addition to their similarity concerning inheritance of autosomal recessive means and clinical course, we found causality relating copper accumulation to the pathogenesis of the disease. We propose that LEC rats will be the most promising animal model for the study of Wilson's disease.

Age Factors↗
PubMed1992

[The relationship between evaluation of school stressors and stress responses in junior high school students].

The purpose of this study is to develop a school stressor scale from the events experienced frequently by junior high school students in their daily school life, and to examine the relationship between school stressors and stress responses. In study I, factor analysis of data by 552 students revealed four main factors "teacher", "friend", "club activity", and "study", which were extracted from initial set of 72 items. In study II, factor analysis of 50 items, of which 39 items were extracted in study I, and 11 new items of free-description type, of data by 622 students, revealed that main stressors in junior high school were following six, "teacher", "friend", "club activity", "study", "rule", and "official activity". Furthermore, multiple regression analyses revealed that "friend" strikingly correlated with "depressive-anxious emotion" and "study" did with "cognition-thought of helplessness".

Adolescent↗
PubMed1992

[Surgical analysis of mediastinal lymphangioma--analysis of 7 cases].

Mediastinal lymphangioma is a very rare disease. In this study, we evaluated 7 surgically treated cases of mediastinal lymphangioma. Four males and 3 females with ages ranging from 5 months to 74 years (average 31.4 years) were examined. Four patients were asymptomatic but had abnormal shadows on their chest X-ray. Of the remaining patients, one had hoarseness and another had superior vena cava syndrome and both had dyspnea. The other patient was discovered because of cervical tumor. Multiple lymphangiomas were found in only 2 patients. One patient had 4 tumors and the other had 2 tumors in the mediastinum. Of all lymphangiomas, 2 were found in the superior mediastinum, 2 in the anterior mediastinum, 3 in the median mediastinum and 3 in the posterior mediastinum. All patients had cystic lymphangioma including 1 with capillary lymphangioma and 1 with cavernous lymphangioma. Median sternotomy was performed in 3 of the patients and posterolateral thoracotomy was performed in the remainder. The cervical tumor was removed by local incision. Complete resection of the lymphangiomas was performed and no recurrence was observed after surgery.

Adult↗
PubMed1991

The improved effects of specific active immunotherapy on a rat fibrosarcoma by antitumor drugs.

We have tried to find out if the combination of a xenogenized tumor cell vaccine and antitumor drugs is able to induce a synergistic increase in the antitumor therapeutic effect. The degree of increase in the LTD50 (50% lethal tumor dose) is expressed numerically, as a quantitative index designed to compare degrees of transplantation resistance to tumor cell challenge. A LTD50 was achieved by an intradermal (i.d.) immunization with xenogenized tumor cells when challenged with tumor cells implanted intraperitoneally 2 weeks after the immunization: this LTD50 value was 527,000 times higher than that of the non-immunized group. When we combined this type of immunization with appropriate doses of bleomycin (BLM) or cyclophosphamide (CY), which are able to augment antitumor immunity, the LTD50 was 723,000-1,190,000 times higher than that of the non-immunized group. This increase in the LTD50 is definitely higher than that achieved by a single immunization with irradiated tumor cells (x 33,000) and combined with either BLM (x 93,000) or CY (x 140,000). We also studied the therapeutic effect of a tumor cell vaccine combined with antitumor drugs BLM or CY in tumor-bearing rats. We observed a synergistic effect caused by BLM or CY after i.d. immunization with xenogenized tumor cells: this showed a significant increase when compared with the therapeutic effects obtained by chemotherapy alone (P less than 0.01). Nevertheless, there was no evidence that the above antitumor effects is superior to the effect achieved by irradiated tumor cells.

Animals↗
PubMed1991

[A case of bronchial artery aneurysm demonstrating a mass shadow on chest X-ray film].

A 66-year-old woman was admitted on May 13, 1989, because of an abnormal round shadow in the right hilum on chest X-ray film. Bronchoscopy revealed a stenosis of the right B8 caused by a bulging lesion. An aortogram showed a large meandering bronchial artery and a saccular aneurysm. The aneurysm was about 25 mm in diameter and associated with a bronchopulmonary anastomosis. It was surgically removed by right lower lobectomy. Pathological examination proved that the resected lesion was an arterial aneurysm. Patchy arteriosclerotic change was present in the intima of the aneurysm, but there was no evidence of inflammatory change in the arterial wall and the adjacent alveoli and bronchi. Twenty-six cases of bronchial artery aneurysm have been previously reported in the literature, but this is the first case that appeared as a solitary nodule on conventional chest X-ray.

Aneurysm↗
PubMed1991

[A mild variant case of maple syrup urine disease].

We reported a mild variant case of maple syrup urine disease. He was unable to walk alone at 2 years of age and developed seizures and intermittent ataxia at 5 years of age. Activity of 1-14C-leucine decarboxylase in fibroblasts revealed 40% of normal activity in the boy and 90% in the mother. MRI showed hypo-myelination of white matter and mild atrophy of brain stem and cerebellum. Dietary treatment was not effective for ataxia and brain atrophy.

Atrophy↗
PubMed1990

Maintenance and cure of the L5178Y murine tumor-dormant state by interleukin 2: in vivo and in vitro effects.

We studied the antitumor effects of recombinant human interleukin 2 (HuIL-2) in DBA/2 mice which harbor L5178Y lymphoma cells in a tumor-dormant state in the peritoneal cavity and in peritoneal cell (PC) cultures prepared from such mice. Intraperitoneal injection of 10,000 to 100,000 units of HuIL-2/day for 10 days eliminated tumor cells from 30-45% of the mice, whereas no mice became tumor-free in the phosphate-buffered saline-treated control group. In vitro, as little as 10 units/well HuIL-2 failed to stimulate cytotoxic activity in PC from normal mice. HuIL-2 directly stimulated antitumor cytotoxic activity in nonadherent but not in adherent PC cultures from tumor-dormant mice; however, treatment of whole PC from tumor-dormant mice with HuIL-2 resulted in the development of antitumor cytotoxic activity in the adherent PC population which were derived from such cultures. This suggests that the HuIL-2-treated nonadherent PC contributed to the cytotoxic activation of the adherent PC. Flow cytometric analysis of the PC from tumor-dormant mice revealed a polyclonal expansion of T-lymphocytes. Lyt-1+, Lyt-2+, and L3T4+ lymphocytes were all required for HuIL-2 to induce antitumor cytotoxic activity.

Animals↗
PubMed1990

Immunological regression of metastatic cancer in the liver as a result of "in vivo xenogenization".

We attempted to induce the regression of liver metastatic tumor cells in vivo by the administration to rats of Friend leukemia virus (FV) (in vivo xenogenization). The virus which was used in this experiment, FV, is highly immunogenic and does not normally cause disease in an adult rat. At first, we induced a FV viremia in tumor bearing rats in order to deliver the virus to the site of the tumor cells. FV viremia was induced by injecting 60 mg/kg cyclophosphamide (CY) i.v. after the administration of FV, and by transferring syngeneic bone marrow cells so that FV would be able to infect them and then replicate. In order that the tumor cells which were infected with virus should regress, it was necessary to break down their tolerance to FV antigens. As adoptive immunotherapy we therefore, transferred syngeneic spleen cells from rats which had been immunized with FV to tumor bearing rats. The result of this experiment was that these tumor bearing rats infected with FV which had received either normal syngeneic spleen cells or no spleen cells as controls died from liver metastasis (8 out of 9 rats (89%) and 15 out of 17 (88%) respectively). On the other hand, only 4 out of the 15 (27%) tumor bearing rats which were infected with FV and which received FV-immune spleen cells died from liver metastasis. These sets of data indicate that the in vivo xenogenization of tumor cells are indeed able to induce the regression of metastatic tumor cells.

Animals↗
PubMed1990

A family case of nephrogenic diabetes insipidus.

Two brothers, patient 1 with fever and vomiting, and patient 2 with failure to gain weight were studied. After 4 hr of water deprivation test, the urinary osmolality of the patient 1 was only 105 mOsm/liter and his body weight showed a 4.6% reduction. In response to desamino-8-D arginine vasopressin intranasal administration, no significant elevation of urinary osmolality of patient 1 occurred. After low dose vasopressin tests, the maximal urinary osmolality of their father was in the normal range, but that of their mother was below the normal range. Moreover, the patients showed no significant increase of urinary osmolality after the same tests. The brothers were diagnosed as nephrogenic diabetes insipidus (NDI) and their mother was diagnosed as a carrier. An early diagnosis of NDI is important, since adequate managements such as low-solute diet with restricted protein and salt intake or such as water intake at frequent intervals can prevent the hyperosmolality which would develop the delayed mental and physical developments. The usefulness of the combination of indomethacin with thiazide diuretics is described.

Adult↗
PubMed1990

[MR imaging of internal carotid artery occlusion].

Five patients with internal carotid artery occlusion were studied with MR imaging at 0.22 T. At the carotid siphon, occluded vessels showed absence of flow void in three patients. But two cases had "partial flow void" which mimicked small arterial caliber. In these patients angiography showed collateral circulation to the carotid siphon. So the partial flow void in the carotid siphon suggested internal carotid artery occlusion with collateral circulation.

Aged↗
PubMed1990

[MR imaging of adenomyosis].

MR imaging characteristics of adenomyosis were studied in nine women (five diffuse type, four focal type) who underwent hysterectomy. In all cases, MR images were correlated with surgical/pathologic findings. On T2-weighted images, diffuse type appeared as a thickening of the junctional zone, because it was often isointense with this zone. Focal type appeared as a low signal intensity, round or oval shaped mass poorly marginated from the adjacent myometrium.

Adult↗
PubMed1989

Cytotoxicity of galactose, tyrosine and methionine in cultured suckling rat hepatocytes: relation to liver immaturity.

Monolayers of suckling rat hepatocytes cultured for 24 hours were treated with galactose, I-tyrosine and I-methionine. The purpose was to study the reasons for the clinical improvement of patients with neonatal hepatitis after dietary restriction of these nutrients. Galactose, tyrosine, and methionine was cytotoxic on suckling rat hepatocytes, yet had no effect on adult rat hepatocytes. Furthermore, the pretreatment of suckling rat hepatocytes with dexamethasone ameliorated the cytotoxicity and induced a differentiation of the cells. These results suggested that the cytotoxicity resulted from the immaturity of suckling rat hepatocytes and therefore dietary restriction of galactose, tyrosine and methionine might be a useful treatment for patients with neonatal hepatitis.

Animals↗
PubMed1989

[A case of benign fibrous histiocytoma of the lung in a child].

A case of benign fibrous histiocytoma of the lung in a 8 years old boy was presented. He was first admitted in May, 1983, with recurrent pneumonia. Chest X-ray showed a ill-defined mass in the right lower lobe. Bronchoscopy revealed a round tumor, 1 cm. in maximum diameter, with complete obstruction of the Truncus Intermedius. Endoscopic resection was performed and partial obstruction of the Truncus Intermedius remained. He was re-admitted with pneumonia of the right middle lobe in March, 1986. Bronchoscopy showed severe stenosis of the Truncus Intermedius. Right middle and lower lobectomy was performed. The 4 X 4 X 3 cm tumor was located in the median of the Truncus Intermedius. Microscopically, the lesion composed of fibroblast-like cells and histiocyte-like cells. The patient's post-operative course was uneventful. He has no signs of local recurrence or metastasis. We believe, this is the first reported primary benign fibrous histiocytoma of the lung in a child in Japan.

Bronchial Neoplasms↗
PubMed1989

[MR imaging of gynecological neoplasms using a low-magnetic-field machine].

Magnetic resonance (MR) images were obtained from 171 patients with benign and malignant neoplasms in the uterus and ovary, by using a low magnetic-field machine with 0.22 T, and its usefulness is discussed. Small uterine neoplasms (a few mm of its diameter) can be detected as an abnormal intensity. Therefore, the detectability is helpful for determination of their staging. In addition, some adenomyosis can also detected as distinctive findings, although it is difficult to point out those diseases by other imaging modalities. From MR images of ovarian cystic tumor, the biochemical information of its fluid content can be obtained. However, it is difficult to get distinctive features from MR images of solid neoplasms. Even though the magnetic field is low such as 0.22 T, MR images are useful for diagnosis of gynecological neoplasms because of the high contrast image quality and the capability of providing tomograms with arbitrary planes.

Adult↗
PubMed1989

[A case of mediastinal schwannoma originating from the intrathoracic vagal nerve].

A 46-years-old man was admitted because of an abnormal shadow on X-ray. The operation underwent under the diagnosis of benign tumor in the antero-superior mediastinum. At the operation, the tumor arise from the right intrathoracic vagal nerve and it was resected with the transection of vagal nerve. The histological diagnosis was schwannoma. Postoperative course was uneventful except the slight hoarseness. Intrathoracic vagal tumor is rare and we have found 19 reported cases among Japanese literatures. This case is considered to be the 20th case originated from the intrathoracic vagal nerve in Japan.

Cranial Nerve Neoplasms↗
PubMed1989

[A case of primary pulmonary cryptococcosis].

A 53-year-old male was admitted because of an abnormal chest roentgenogram showing a solitary tumor shadow in the right upper lung field. Laboratory data was normal. Although examination with the bronchoscope and sputum cytology showed no abnormal findings, a partial resection of the right upper lobe was performed. Microscopic examination of the lesion was cryptococcosis. As another focus was not found by systemic examination, the lesion was disclosed primary pulmonary cryptococcosis. Cryptococcosis is rare but we must think of it when we meet a solitary tumor shadow on the chest roentgenogram.

Cryptococcosis↗