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Biomedical subjects

H Hashimoto

Publications and source records attributed to H Hashimoto.

At least 1,135 records · Page 63Linked to original sources

Effects of castration before and after treatment with N-bis (2-hydroxypropyl)-nitrosamine (DHPN) on the development of thyroid tumors in rats treated with DHPN followed by phenobarbital.

The effect of castration on the development of thyroid tumors was studied histologically and biochemically in Wistar rats given a single ip injection of 210 mg of N-bis (2-hydroxypropyl)-nitrosamine (DHPN) followed by phenobarbital (Pb). Castration was performed one week after, or one week before the injection of DHPN. The injection of DHPN was given at the end of the first week, and the rats were fed 500 ppm Pb in the basal diet for 38 weeks from week 3 to week 40. The incidence of thyroid adenomas and cancers was 20% (4/20) and 10% (2/20) in rats treated with DHPN alone. It was 75% (15/20) and 40% (8/20) in rats treated with DHPN and Pb; 30% (6/20) and 15% (3/20) in rats treated with DHPN and Pb, and castrated after DHPN; 20% (4/20) and 0% in rats treated with DHPN and Pb, and castrated before DHPN and Pb; and 0% and 0% in rats castrated either before or after receiving DHPN. Castration thus inhibited the development of thyroid tumor in rats treated with DHPN. The inhibition of tumor development in rats treated with DHPN and Pb, and castrated before receiving DHPN, was greater than in the rats castrated after receiving DHPN. Castration inhibited the secretion of TSH in rats treated with DHPN and Pb.

Animals↗

[Squamous cell carcinoma of renal pelvis: a case report and review of the Japanese literature].

Squamous cell carcinoma of renal pelvis is relatively rare and its prognosis is very poor. A 72-year-old man was introduced to our institute because of macroscopic hematuria. He had no history of urolithiasis or urinary tract infection. Excretory urography showed a nonfunctioning right kidney. Cytologic examination of urine was positive for malignant cell from squamous cell carcinoma. Preoperative diagnosis was made as right renal pelvic tumor, but it appeared to be renal tumor on the roentgenogram. Right radical nephrectomy and transurethral ureterectomy was performed. Radiation therapy was done after operation. Pathological diagnosis was squamous cell carcinoma of renal pelvis extensively infiltrating to the renal parenchyma. The patient is alive with no recurrence or metastasis for eight months after operation. Statistical analysis was made on 136 cases of squamous cell carcinoma of renal pelvis reported in the Japanese literature including our case, and this disease is also briefly reviewed.

Aged↗

Reciprocal potentiation of a vasoconstrictor response between 5-hydroxytryptamine and clonidine in the perfused mesenteric vascular bed of the rat.

The interaction between 5-hydroxytryptamine (5-HT) and clonidine, an alpha 2-adrenoceptor agonist, was investigated in the isolated perfused mesenteric vascular bed of the rat. Clonidine itself did not cause vasoconstriction even at 300 micrograms. However, clonidine in the presence of 5-HT (10 and 100 nM) caused a marked vasoconstriction in a dose range of 0.1 micrograms to 300 micrograms. Prazosin inhibited the clonidine response, whereas yohimbine did not. The potency of prazosin against clonidine was less than that against an alpha 1-adrenoceptor agonist phenylephrine. Therefore, it is suggested that clonidine activated alpha 1-like adrenoceptors. 5-HT also potentiated the vasoconstrictor response to perivascular nerve stimulation, exogenous norepinephrine (NE) and phenylephrine. Calcium entry blockade by nicardipine (0.1 microM) reduced the response to clonidine in the presence of 5-HT, whereas that to phenylephrine in the presence or absence of 5-HT was not reduced. On the other hand, clonidine (0.01-1 microM) potentiated the vasoconstrictor effect of 5-HT more than NE did. Ouabain (1 microgram/ml) enabled clonidine to exhibit an agonistic action, and also enhanced the contractile response to 5-HT. In conclusion, 5-HT modulated the vasoconstrictor effect of clonidine, and the vasoconstriction with 5-HT was also facilitated by clonidine reciprocally. It is possible that a partial depolarization of the cell membrane is the common mechanism for their reciprocal potentiation.

Animals↗

A multicenter double blind controlled study of lipo-PGE1, PGE1 incorporated in lipid microspheres, in peripheral vascular disease secondary to connective tissue disorders.

Lipo-PGE1 is a drug preparation of PGE1 (prostaglandin E1) incorporated in lipid microspheres similar in properties to liposomes. A multicenter, placebo controlled, double blind test of lipo-PGE1 was carried out in patients with severe peripheral vascular disease secondary to diffuse connective tissue disorders. A total of 135 patients received a 90 min intravenous infusion of either 10 micrograms lipo-PGE1 or placebo every day for 4 weeks. A significant improvement was noted in the lipo-PGE1 group compared with the placebo group in the final overall improvement of peripheral vascular disease (p less than 0.001) and in the healing of ulcers (p less than 0.01), whereas, there was no difference in Raynaud's syndrome between the 2 groups. Side effects in the lipo-PGE1 group were few and were no different from controls. These results indicate that lipo-PGE1 at a low dose is beneficial in the treatment of peripheral vascular disease, and that lipid microspheres are useful as a drug delivery system for such purposes.

Adolescent↗

Changes in serum glucose and serum growth hormone levels during pituitary surgery.

During transsphenoidal surgery, serum growth hormone (GH) and serum glucose levels were measured in five acromegalic patients with diabetes or glucose intolerance, three acromegalic patients without diabetes or glucose intolerance, and six patients with prolactinoma. Preoperative steroid administration produced a significant increase in serum glucose level in acromegalic patients with diabetes or glucose intolerance, whereas in the other two groups no significant change in serum glucose level was found. After surgery started, there was a statistically significant increase in serum glucose level above baseline levels in all three groups. Serum GH levels decreased after commencement of surgery in acromegalic patients, and tumor manipulation did not produce a statistically significant increase in serum GH levels. Simultaneous increases in serum glucose and serum GH levels upon tumor manipulation did not occur in any group. We conclude that preoperative steroid administration in patients with high serum levels of GH in association with diabetes or glucose intolerance increases serum glucose levels, and that, after commencement of surgery, GH has only a minor role in the changes of serum glucose levels.

Acromegaly↗

Differences in clinical and immunological findings of systemic lupus erythematosus related to age.

Five hundred and seventy patients with systemic lupus erythematosus were classified into 3 groups (younger onset, adult onset and older onset) according to their ages at the time of diagnosis. There were more patients with HLA-Bw35 and/or DR2 in the younger onset group than the adult onset group. Typically related systemic features and serological abnormalities were more frequently found in the younger onset group than the other groups. The disease patterns of the adult onset group were more heterogeneous than those of the other 2 groups. The causes of death in the older onset group were mainly complications such as infections and perforated peptic ulcers.

Adolescent↗

Histogenesis of Kaposi's sarcoma associated with AIDS: a histologic, immunohistochemical and enzyme histochemical study.

Twenty-one cases (25 biopsies including 9 frozen biopsies) of Kaposi's sarcoma associated with the acquired immune deficiency syndrome (AIDS) were examined immunohistochemically, lectin-histochemically, and enzyme histochemically to ascertain the histogenesis of the lesion. The Kaposi's sarcomas were histologically subtyped according to a modified Schmid's classification (granulation tissue-like-, angiosarcoma-like- and spindle cell type). In almost all lesions, many atypical vasoforming cells and at least some spindle cells without definite evidence of vasoformation by conventional microscopy were positive for factor VIII-related antigen, BMA 120 (a new monoclonal antibody to an endothelial cell-specific antigen), Ulex europaeus I (UEA-I), alkaline phosphatase and ATPase. Linear reaction products for BMA 120 and UEA-I, suggesting the luminal surface of immature vascular channels, were sometimes recognized in the positive spindle cells. Electron micrographs confirmed endothelial characteristics, such as irregular and fragmented but distinct basal lamina and numerous pinocytotic vesicles, in both the UEA-I- and ATPase-positive spindle cells. Among spindle cells negative for the endothelial markers, there were many macrophages as a stromal reaction to tumor tissue, identified by monoclonal antibodies to macrophages (KiM 6, 7, 8 and EBM 11), acid phosphatase and alpha-naphthyl acetate esterase. The results of the immuno- and enzyme histochemical investigations did not correlate with the different histologic types of Kaposi's sarcoma. However, our results strongly suggest that tumor cells of Kaposi's sarcoma are derived from vascular endothelial cells rather than lymphatic endothelium.

Acquired Immunodeficiency Syndrome↗