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Biomedical subjects

Y Nagashima

Publications and source records attributed to Y Nagashima.

At least 181 records · Page 10Linked to original sources
PubMed1993

Affinity chromatographic purification of tetrodotoxin by use of tetrodotoxin-binding high molecular weight substances in the body fluid of shore crab (Hemigrapsus sanguineus) as ligands.

A purification method for tetrodotoxin (TTX), based on affinity chromatography using the TTX-binding high mol. wt substances in the body fluid of shore crab (Hemigrapsus sanguineus) as ligands, was developed. This method was particularly useful for analysis of TTX in biological samples with low concentrations of TTX. The affinity gel prepared was highly specific for TTX, having no ability to bind 4-epi-TTX and anhydro-TTX as well as saxitoxin.

Ammonium Sulfate↗
PubMed1993

[Clinical and experimental study of hemodynamic changes during aortic surgery].

To clarify the influence of clamping of aorta on ischemic heart, 235 patients who underwent abdominal aortic surgery from 1980 to 1989 were studied. One hundred and twenty patients underwent resection of abdominal aortic aneurysm, and 115 patients underwent operation for aortoiliac occlusive disease. Myocardial infarction occurred in 8 patients, and 4 patients died. The onsets of the myocardial infarction were later than the 3rd post operative day in every patient but one. There were no significant differences in the incidence of myocardial infarction between the patients of nonruptured abdominal aortic aneurysm and of aortoiliac occlusive disease. To clarify the hemodynamic changes during abdominal aortic procedure, following experiments were performed using dogs. The dogs were divided into 6 groups, Groups 1, 3, 5; normal control groups, Group 2, 4, 6; groups with coronary stenoses. The infrarenal aorta were cross-clamped in groups 1, 2, 3, 4. In groups 3 and 4, PGE1 were administrated continuously into the infrarenal aorta below the clamping sites. In groups 5 and 6, descending thoracic aorta were cross-clamped. In group 6, one dog developed ventricular fibrillation at 60 minutes after aortic cross-clamping. Moreover ECG of the other dog of group 6 demonstrated myocardial ischemia during aortic clamping. But there were no significant differences in hemodynamic variables between groups, 1, 3, 5 and 2, 4, 6. These results indicate that aortic clamping can induce the myocardial ischemia, but that ischemia is not the chief cause of postoperative myocardial infarction.

Adult↗
PubMed1993

[Successful management for advanced renal cell carcinoma under combination therapy with human lymphoblastoid interferon-alpha and UFT (mixture of tegafur and uracil): a case report].

We report a case of renal cell carcinoma in a 76-year-old man with pulmonary metastasis and tumor thrombus in inferior vena cava. The patient responded to the combination therapy with a small amount of HLBI (human lymphoblastoid interferon-alpha) and UFT (1:4 mixture of tegafur and uracil). HLBI was administered intramuscularly at a dose of 3 x 10(6) IU two times a week. However, the administration of the same dose was discontinued, because of the severe side effects, such as depression, general fatigue, anorexia and high fever. Finally, the maximum dose was determined to be 2 x 10(6) IU/week. Nine weeks after the first treatment, UFT was simultaneously given orally at a dose of 100 mg/day for potentiating the antitumor effect. At 12 weeks, the patient registered complete response of pulmonary metastasis, and partial response (83% reduction) of renal tumor. About 60 x 10(6) IU HLBI was administered until the response was noted. After 34 weeks of administration of HLBI, nephrectomy was performed. Histological diagnosis was renal cell carcinoma of clear cell subtype, grade 2. Microscopically, many lymphocytes infiltrated into the cancer cells. This suggests the possibility of immunological response caused by HLBI.

Aged↗
PubMed1992

Isolation of subclones with different tumorigenicity and metastatic ability from rat nephroblastoma cell line, ENUT.

Seven subclones derived from a chemically induced rat nephroblastoma cell line, ENUT, were isolated and their cytological characteristics were examined in order to investigate the biological nature of the parent tumor. The subclones were divisible into two types based on morphological and biological features: polygonal cells with well developed junctional complexes and less developed cell surface microvilli, showing a doubling time of 13.0 to 14.0 h and tumorigenicity in nude mice of 42-100%, and spindle-shaped cells with poorly developed junctional complexes and well developed microvilli, showing a doubling time of 9.7 to 12.2 h and 100% tumorigenicity. Potential for both spontaneous and experimental metastasis to the lungs was apparently higher in the spindle-shaped clones than in the polygonal clones. In spite of their differing characteristics, the cytochemical phenotypes of the two clonal types were almost identical to those of immature renal tubules of the developing fetal kidney. The present findings suggest that these subclones possess characteristics of early nephrogenic epithelial cells, and we speculate that the biological differences observed among the subclones may be explained by differences in malignant progression. In addition, these clones appear to be a useful model for the study of tumorigenicity and metastasis.

Animals↗
PubMed1992

Alpha-fetoprotein-producing immature mediastinal teratoma showing rapid and massive recurrent growth in an adult.

A case of immature mediastinal teratoma in a 43-year-old Japanese man is reported. The tumor, which was multicystic with solid zones and measured 12 x 6 x 8 cm, arose in the anterior mediastinum. The serum alpha-fetoprotein (AFP) level was elevated to 5,114 ng/ml before surgery. Histologically, the solid zones showed an admixture of irregular glands lined by columnar or cuboidal epithelium set in a spindle cell stroma, some foci of primitive neural tissue, and scattered small nests of hepatoid cells. Immunohistochemically, the hepatoid cells and epithelia lining some of the cysts showed a strongly positive reaction for AFP. Eight months after surgery, the patient died of respiratory failure caused by a rapidly growing massive recurrent tumor, which measured 40 x 24 x 13 cm, in the left thoracic cavity. However, the elevated serum AFP level had been decreasing during the course of the recurrence in response to chemotherapy. The recurrent tumor showed remarkable proliferation of loose mesenchymal tissue without primitive neural tissue. These findings suggest that immature mediastinal teratoma in adults is highly malignant, and that non-AFP-producing mesenchymal tissue played a critical role in forming the rapidly growing massive recurrent tumor in the present case.

Adult↗
PubMed1992

Glomerular lesions in unilateral nephrectomized and diabetic (UN-D) mice.

Experimental diabetes was induced in both control and unilaterally nephrectomized male mice by injecting streptozotocin (SZ) (50 mg/kg x 5 days) one week after nephrectomy. The time course changes in the glomerular lesions were examined for up to 12 weeks after completion of the SZ-injection (12WAI). In unilateral nephrectomized and diabetic mice, mild segmental expansion of the mesangial area developed at 4WAI, and it progressed to prominent segmental glomerulosclerosis at 12WAI. In the electron microscopic examination at 12WAI, marked expansion of the mesangial area, segmental thickening of the glomerular basement membrane, fusion of the foot processes of podocytes and a prominent increase in the number of microvilli of capillary endothelial cells were observed. On the other hand, mild to moderate expansion of the glomerular mesangial area was only sporadically found in unnephrectomized diabetic mice at 12WAI. Interestingly, Bowman's capsules of diabetic mice were generally lined with flattened epithelia but those of non-diabetic mice with cuboidal or low columnar epithelia.

Animals↗
PubMed1992

Characterization of experimental rat nephroblastoma and its cell line.

Rat nephroblastoma (Wilms' tumor) was induced by transplacental administration of N-ethyl-nitrosourea (ENU). The induced renal tumors were histologically compatible with human nephroblastoma. A cultured cell line (ENU-T-1) established from a xenotransplant, showed similar morphological and biological features to cultured embryonal kidney cells. Introduction of normal human chromosome #11 (#11) bearing Wilms' tumor suppressor gene(s) (WT) suppressed colony-forming ability on soft agar plates (CFA) but tumorigenicity of ENU-T-1 was not affected. Whereas tumorigenicity of human nephroblastoma cell line, SK-NEP-1 was completely suppressed, CFA was unchanged. These facts indicated that pathogenetic mechanism is different between human and experimental rat nephroblastomas.

Animals↗
PubMed1992

[A 13-week percutaneous toxicity study of prednisolone farnesylate (PNF) gel in beagle dogs with a recovery period of 5 weeks].

The toxicity of Prednisolone farnesylate (PNF) gel, a synthetic glucocorticoid, was investigated in the Beagle dog. PNF gel was administered percutaneously at doses of 0.2, 0.8 and 3.2 mg/kg/day for 13 weeks, then the drug was withdrawn for 5 weeks to evaluate the reversibility. In addition, 2 mg/kg/day prednisolone gel (PN gel), which is approximate to 3.2 mg/kg/day PNF gel in prednisolone molarity, was also administered for comparison. The results are summarized as follows: 1. No deaths were observed in any of the PNF gel test groups or the PN gel group, nor were there any abnormal findings in the clinical signs of the animals. 2. In the hematology, a tendency toward a decrease in the lymphocyte ratio was observed in males from the PNF gel 0.8 mg/kg/day and above groups. In the PN gel group, a significant decrease or a tendency toward a decrease in the lymphocyte ratio was observed, as well as an increase in the white blood cell count in some animals. 3. In the blood biochemistry, a significant decrease or a tendency toward a decrease in total cholesterol and phospholipid was observed in males from the PNF gel 3.2 mg/kg/day group and a tendency toward an increase in triglyceride in females from the PNF gel 3.2 mg/kg/day group was observed. In the PN gel group, a tendency toward an increase in AIP activity, a tendency toward an increase in triglyceride were observed. 4. In the histological examinations, a decrease in the weight of the thymus and adrenal glands, vacuolation of hepatocytes in the middle zone of the liver, atrophy of zona fasciculata of the adrenal glands, hypertrophy of zona glomeruli, swelling of cortical cells of zona faciculate and atrophy of the thymus were observed in the PNF gel 0.8 mg/kg/day and above groups. In the PN gel group, atrophy of submandibular lymph nodes and mesenteric lymph nodes was observed in addition to the same changes as observed in the PNF gel groups. Furthermore, thinning, atrophy or a decrease in the weight of the adrenal glands was also observed both in the PNF gel 3.2 mg/kg/day group and the PN gel group at the end of the 5-week recovery period. 5. As described above, a decrease in the lymphocyte ratio, in the weight of the thymus and adrenal glands and vacuolation of hepatocytes were observed in the PNF gel 0.8 mg/kg/day and above groups.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Cutaneous↗
PubMed1992

[A 52-week percutaneous toxicity study of prednisolone farnesylate (PNF) gel in beagle dogs with a recovery period of 8 weeks].

The toxicity of Prednisolone farnesylate (PNF) gel, a synthetic glucocorticoid, was investigated in the Beagle dog. PNF gel was administered percutaneously at doses of 0.05, 0.2 and 0.8 mg/kg/day for 52 weeks, then the drug was with held for 8 weeks to evaluate reversibility. The results are summarized in the following. 1. In the 0.05 mg/kg/day and above groups, hypotrichosis in the application site of the skin, thinning of the skin and atrophy of the appendages, and in the 0.2 mg/kg/day and above groups a tendency toward retarded body weight gain, were observed. 2. In the 0.2 mg/kg/day and above groups, a drop in the lymphocyte ratio, a rise in GOT activity and A1P level, and in the 0.8 mg/kg/day group a rise in free fatty acid were observed. 3. In the 0.2 mg/kg/day group and above groups, atrophy of the zona fasciculata and zona reticularis were observed. In the 0.8 mg/kg/day group, a decrease in the weight of the thymus and adrenal glands, and a increase in the weight of the liver, were observed. 4. At the end of the recovery period, most of the changes disappeared, except for those in the adrenals and treated area. From the above results, under the conditions of this study, it was concluded that when the changes observed in the application site of the skin in each group were not taken into consideration, the toxicological no effect level was 0.05 mg/kg/day for both males and females and the overt toxic dose level was 0.8 mg/kg/day.

Administration, Cutaneous↗