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Biomedical subjects

M Hosaka

Publications and source records attributed to M Hosaka.

At least 253 records · Page 14Linked to original sources
PubMed1985

[A case of metastatic renal cell carcinoma with complete remission achieved by interferon therapy].

A case of metastatic renal cell carcinoma in which complete remission was achieved using Interferon therapy is reported. A 67-year-old male was found to have extensive paraaortic lymph node metastasis while undergoing left nephrectomy following diagnosis of 1-renal cancer. Pathological diagnosis of the node was metastasis of clear cell type renal cell carcinoma. Interferon (Hu IFN-alpha 2: Sch 30500; Yamanouchi Pharmaceutical Co.) therapy was started 34 days after surgery. The Interferon was administered i.m. at a dose of 1 X 10(6) units per injection, 3 times a week, and was continued up to a total dose of 236 X 10(6) units. Response of the metastatic lymph nodes was examined using CT scan. Marked response was observed 4 weeks after starting the Interferon therapy, and complete disappearance of the tumors was obtained 5 months after Commencement of therapy. The duration of complete response has lasted 4 months. The toxic manifestations of the Interferon therapy were fever and loss of appetite.

Aged↗
PubMed1985

[Soft agar culture of human prostatic carcinoma--effect of testosterone on the clonal growth of the cells].

Soft agar cultures of human prostatic carcinoma cells obtained from prostates with needle biopsy and metastatic lymph nodes were examined. Colony formation were observed in 2 of the 4 needle biopsy specimens and in 7 of the 10 lymphatic nodes specimens. The plating efficiency was 0.04 to 0.43%. The effect of testosterone on the clonal growth of these cells in soft agar culture was studied. In half of the cases, colony formation was increased by the addition of testosterone. Whereas in the other cases, colony formation was not influenced by the testosterone. Clinically, most of the former cases responded well to the anti-androgen therapy. Neither EGF nor hydrocortisone showed any effect on the colony formation of the prostatic cancer cells in soft agar. These results suggest that primary culture of human prostatic cancer is possible in soft agar medium, and that androgen dependency of these cells can be examined in vitro.

Adenocarcinoma↗
PubMed1984

NaCl induced ornithine decarboxylase and DNA synthesis in rat stomach mucosa.

Inductions of 200-fold increase in ornithine decarboxylase activity within 6 hours and 9-fold increase in DNA synthesis within 3 hours in rat stomach mucosa were observed after a single oral dose of saturated NaCl solution. NaCl caused dose-dependent induction of ornithine decarboxylase activity at doses of 0.25 to 1. 5g /kg body weight, and of DNA synthesis at doses of 0. 5g to 1. 5g /kg body weight. Administration of 1,3-diaminopropane one hour before NaCl inhibited the induction of ornithine decarboxylase activity in the stomach mucosa 3 and 6 hours after NaCl administration, but a single dose of 1,3-diaminopropane itself induced ornithine decarboxylase after 16 hours.

Animals↗
PubMed1984

Immunohistochemical demonstration of epidermal growth factor and nerve growth factor in experimental carcinogenesis in the mouse submandibular gland.

Immunohistochemical demonstration of epidermal growth factor (EGF) and nerve growth factor (NGF) was made during chemical carcinogenesis in the mouse submandibular gland. The granular convoluted tubule cells in the normal male submandibular gland contained larger amounts of EGF and NGF than in the female. The initial phase and early stages in chemical carcinogenesis showed degranulation of the granular convoluted tubule cells with a marked decrease in EGF and NGF. Premalignant lesions such as duct-like structures and multicystic lesions showed variable staining for EGF and were usually negative for NGF. Material secreted into the luminal spaces revealed increased staining for EGF and NGF. Scattered tumor cells of the poorly differentiated squamous-cell carcinoma type and desquamated tumor cells contained abundant EGF, but not NGF. No positive reaction for EGF or NGF was found in the induced squamous-cell carcinoma cells.

Animals↗
PubMed1984

Keratin distribution in precancerous stages of experimental carcinogenesis in mouse submandibular glands.

The immunohistochemical distribution of keratin is reported in experimental carcinogenesis in the mouse submandibular gland (SMG). The initial changes included degranulation of granular convoluted tubule (GCT) cells and the appearance of keratin in the degranulated cells. There was a gradual increase in the area showing keratin staining in the altered tubule cells. Duct-like and cystic structures exhibited an intense keratin staining of their lining epithelium. The squamous cell carcinomas induced varying degrees of keratinization and positive immunohistochemical keratin staining. The latter technique provided a useful marker for distinguishing tumor cells of segmental duct origin in the salivary gland.

Animals↗
PubMed1984

Histopathologic studies of DMBA-induced mouse submandibular-gland tumors with or without cryoprobe treatment.

Histopathologic observations of 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced tumors in the mouse submandibular glands are reported using cryoprobe treatment. The experimental animals were divided into 2 groups; one received a carcinogen injection into the normal submandibular gland, and the other was injected with DMBA on the 14th day following cryosurgery of the gland using a -60 degrees C cryoprobe. Pathologic findings were classified as premalignant lesions or squamous-cell carcinomas with varying degrees of keratinization, fibrosarcoma and mixed carcinoma. There was also one case each of malignant pleomorphic adenoma and cystic adenoma. Tumor incidence was nearly the same in the 2 groups. Most of the carcinomas and sarcomas in the submandibular gland were induced during the 12th and 17th weeks. DMBA application during the proliferating stage which followed the cryosurgery did not enhance epithelial-tumor induction. During submandibular gland carcinogenesis, alterations in the granular convoluted tubule cells suggests they were the initial target cells undergoing malignant transformation. Squamous-cell carcinomas with varying degrees of keratinization were induced following squamous metaplasia in duct-like structures or multicystic lesions.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1984

Histochemical studies on Concanavalin A-binding in experimental carcinoma of the mouse submandibular gland.

The lectin, Concanavalin A(Con A) has been used to localize specific sugar residues (D-glucose, D-mannose and D-fructose) in premalignant lesions and squamous-cell carcinomas induced following cryosurgery of the mouse submandibular gland. The original Con A-horseradish peroxidase (HRP) technique as well as its combination with periodate oxidation and subsequent reduction by borohydrate were used to compare the epithelial elements during submandibular gland carcinogenesis. Granules in the granular convoluted tubule cells which were weakly reactive to the Con A-HRP method were not present in the premalignant duct like structures. The epithelium of premalignant lesions, duct-like structures, multicystic lesions, and squamous-cell carcinomas were positive for the cell-surface and intercellular substances; and basement membranes and stromal fibers were also positive. The results indicated that throughout malignant transformation of the ductal segments, premalignant epithelia lost Con A-HRP-staining granules and that Con A-binding patterns in induced squamous-cell carcinomas were similar to those found in squamous-cell epithelium.

Animals↗
PubMed1984

Lectin-binding in premalignant lesions during submandibular gland carcinogenesis.

Complex carbohydrates in premalignant lesions of mouse submandibular gland tumors were examined by the lectin-peroxidase conjugate method. Peroxidase-conjugated lectins of PNA, RCA-1, DBA, SBA, UEA-1 and WGA were used to detect specific sugar residues of complex carbohydrates in premalignant lesions during experimental carcinogenesis. Marked reduction of PNA and SBA bindings occurred in duct-like structures and cystic lesions which were transformed from granular convoluted tubule cells. Premalignant lesions bound slightly to PNA, RCA-1, DBA, SBA and WGA and manifested increased UEA-1 binding. Squamous metaplastic epithelia of premalignant lesions manifested increased binding to PNA, RCA-1 and SBA as compared to those of duct-like structure and cystic epithelia.

Amino Sugars↗
PubMed1984

Histochemical observations of lectin-binding in experimental carcinomas in mouse submandibular glands.

Peroxidase-conjugated lectins were used for the histochemical detection of carbohydrates in experimental carcinomas of mouse submandibular glands. Induced carcinomas, 43 lesions from 25 cases, were examined histochemically with galactose-binding lectins (PNA and RCA-1), N-acetyl-galactosamine-binding lectins (DBA and SBA), a fucose-binding lectin (UEA-1), and a N-acetyl-glucosamine-binding lectin (WGA). In non- or slightly keratinized squamous-cell carcinomas, the lectin binding of PNA, RCA-1, DBA, SBA, and WGA was weak in tumor epithelia, and UEA-1 binding was slight. In highly keratinized squamous-cell carcinomas, lectin binding was increased in tumor epithelia, but no reaction was noted in completely keratinized regions. Desquamated materials in lumens of tumors gave an intense stain with lectins. Stromal connective tissue, including collagen fibers and basement membranes stained intensely. Lectin binding to submandibular carcinomas was different from binding to granular convoluted tubules and the striated ducts of the normal submandibular gland.

Amino Sugars↗
PubMed1983

[Changes in testosterone and dihydrotestosterone in the rat submandibular gland during development].

The present investigation deals with the changing profile of testosterone (T) and 5 alpha-dihydrotestosterone (DHT) concentrations in the rat submandibular gland (SMG) with age. T and DHT concentrations in SMG from male and female Wistar Rats 0 to 10 weeks of age were measured by a specific radioimmunoassay. T and DHT in male and female SMG showed lower values until 3 weeks (4.5 +/- 1.5 ng/g). However, at 4 weeks of age, T levels greatly increased, revealing 15.1 +/- 6.3 ng/g for males and 18.4 +/- 6.6 ng/g for females. And thereafter from 5 to 10 weeks of age, T concentrations in SMG were decreased to 3--5 ng/g. On the other hand, from 5 to 10 weeks of age, DHT concentrations in both males and females had a tendency to be accumulated, indicating approximately 1.5--3 times higher than T. It can be reasonably concluded that DHT began to be accumulated in SMG at the period of 4 to 5 weeks of age. Furthermore, it is suggested that the rat SMG demands androgen from approximately 4 weeks of age for growth and function.

Aging↗
PubMed1980

Partial characterization of 5 alpha-reductase in the human epididymis.

The properties of 5 alpha-reductase in the human epididymis were studied. When testosterone-4-14C was incubated with the whole homogenate of human epididymis in the presence of NADPH, the identifed metabolites of the substrate were 5 alpha-dihydrotestosterone and 5 alpha-androstane-3 alpha, 17 beta-diol. 5 alpha-reductase activity was mainly localized in the microsomal and nuclear fractions. The Km values of the 5 alpha-reductase for testosterone in the microsomal and nuclear fractions were 1.07 x 10(-8) M and 0.83 x 10(-8) M, respectively. The optimum pH of the 5 alpha-reductase activity was 5.7 for the microsomal fraction and 5.5 for the nuclear fraction. The optimum temperature was about 48 degrees C for 5 alpha-reductase in both the microsomal and nuclear fractions. The most preferable cofactor for the microsomal 5 alpha-reductase was NADPH and the Km value of the enzyme for NADPH was 2.1 x 10(-6) M. These results confirm the presence of 5 alpha-reductase in the human epididymis and suggest that the enzyme has considerable affinity for testosterone and that the properties of 5 alpha-reductase in the microsomal fraction are similar to those in the nuclear fraction.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed1978

Studies of the human testis. X. Properties of human chorionic gonadotropin receptor in adult testis and relation to intratesticular testosterone concentration.

Receptors for [125I]hCG were found in adult human testis. The specific binding of [125I]hCG to testicular receptor is temperature dependent and is a saturable process with respect to added receptor protein and hormone. Scatchard analysis revealed a dissociation constant of 5.0 X 10(-10) M, and 6.2 fmol binding site/mg protein. Intact unlabeled hCG effectively inhibits the specific binding of [125I]hCG to human testicular receptors. For inhibition of binding of [125I]hCG, the alpha subunit has 3.0% of the potency of intact hCG and the beta subunit has 0.4% of the potency of intact hCG. Specific binding is pH dependent, with an optimum at pH 7.4. Brief exposure to extremes of pH causes irreversible damage to the receptors. Incubation with protease and trypsin results in an almost complete loss of binding activity, while ribonuclease, deoxyribonuclease, phospholipase C, or neuraminidase treatment does not significantly alter hormone-binding activity. Binding activity was found to be positively correlated to the concentration of intratesticular testosterone.

Adult↗