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J Nagahama

Publications and source records attributed to J Nagahama.

10 recordsLinked to original sources
PubMed1984

Increased activities of liver cathepsins T and D in carbon tetrachloride-treated rats.

Changes in activities of a new proteinase cathepsin T as well as some other lysosomal acid proteinases and hydrolases were examined in liver homogenate from rats treated with a single hepatotoxic dose of carbon tetrachloride. The most striking changes were several-fold increases of liver cathepsin T and D activities over their levels in untreated rats 3 days after administration of the agent to rats. Increase of cathepsin T was greater than that of cathepsin D at all doses of the hepatotoxin examined. The activities of N alpha-benzoyl-DL-arginine 2-naphthylamide hydrolase, acid phosphatase, beta-galactosidase and beta-glucuronidase in poisoned rat liver were unchanged or only slightly increased. Cathepsin T and D activities were less enhanced in mitochondrial lysosomal fractions than in the homogenate, and were greatly elevated in the supernatant fractions of liver from the treated rats. As judged from the molecular weights, the elevated activities of cathepsins T and D in the treated rat liver could be attributable to the two cathepsins themselves and not to other proteinases. Administration to rats of other hepatotoxic agents, thioacetamide and dimethylnitrosamine, also induced the elevation of the two cathepsin activities in liver, but on partial hepatectomy the activities of liver cathepsins T and D did not show such marked increases. Nonparenchymal liver cell fractions were responsible for almost all the increased activities of liver cathepsins T and D. It is possible that cathepsins T and D play a role in the heterolytic breakdown of hepatocyte molecules following CCl4 poisoning.

Animals↗
PubMed1983

Glucagon degradation in fraction of big plasma glucagon in rats treated with carbon tetrachloride.

When whole plasma obtained from rats given carbon tetrachloride was applied to a column of Bio Gel P-30, P-150 or P-300, a large molecular form of immunoreactive glucagon (IRG), so called "big plasma glucagon" (BPG), was eluted in the void volume. Glucagon degrading activity, measured under the same conditions as for radioimmunoassay of IRG, was eluted in parallel with IRG. Since standard assay mixture containing aprotinin was used for the measurement of IRG, this degradation of glucagon might be due to an enzyme(s) other than serine proteinases. p-Hydroxymercuribenzoate depressed glucagon degradation and IRG in the BPG fractions to 20% and 30% of the control values, respectively. Other inhibitors of thiol proteinases, such as N-ethylmaleimide and leupeptin, also decreased the values for both glucagon degradation and IRG to a similar extent. However, phenylmethylsulfonyl fluoride and pepstatin had little or no effect on these values. On filtration of plasma from carbon tetrachloride-treated rats on a column of Bio Gel A-1.5m, IRG peaks between 600k and 1,200k daltons were obtained and glucagon degrading activity was again eluted with IRG. When p-chloromercuriphenyl sulfonate and N-ethylmaleimide were added to the elution buffer and assay mixtures, the glucagon degrading activity was almost completely inhibited and the values for IRG between 600k and 1,200k daltons were decreased to less than 10% of those of the control. These results indicate that more than 90% of the IRG in the fractions of BPG obtained from carbon tetrachloride-treated rats could be accounted for entirely by the degradation of immunoreactive 125I-glucagon by plasma proteinases, probably thiol proteinases. Thus we conclude that some proteinases are still active in the radioimmunoassay system of glucagon which is widely used at present, and lead apparently higher glucagon values owing to degradation of 125I-glucagon.

Animals↗
PubMed1980

Hepatic gluconeogenic key enzymes in patients with hepatic cancer.

Key enzymes of gluconeogenesis in the liver, phosphoenolpyruvate carboxykinase [EC 4.1.1.32] and glucose-6-phosphatase [EC 3.1.3.9], were studied in patients with primary or metastatic hepatic cancer. Liver specimens for enzyme assay were obtained by necropsy performed within four hours after death. It was confirmed that both enzyme activities in rat liver preserved at 4 degrees C remained unchanged within nine hours after the removal of the tissue. Activities of phosphoenolpyruvate carboxykinase and glucose-6-phosphatase decreased to below ten per cent of the control in neoplastic liver tissue of patients with hepatocellular carcinoma accompanied with liver cirrhosis. These two enzyme activities in cirrhotic tissue of patients with hepatocellular carcinoma were lower than those in patients merely with cirrhosis. In patients with metastatic hepatic cancer both two enzyme activities further decreased and were scarcely detected not only in neoplastic tissue but also in non-neoplastic tissue. These results show that hepatic gluconeogenesis markedly decreases in patients with primary or metastatic hepatic cancer. The biochemical analysis of the blood in hepatic cancer, decreased in blood glucose and release in immunoreactive glucagon, also suggested the suppression of gluconeogenesis.

Adult↗
PubMedDate not supplied

Cytologic features of solid and cystic tumor of the pancreas.

OBJECTIVE: To describe the cytologic features of solid and cystic tumor of the pancreas. STUDY DESIGN: Cytologic features of four cases of solid and cystic tumor of the pancreas (SCT) were reported and compared with those of three cases of islet cell tumor of the pancreas. RESULTS: Aspiration and imprint cytology of the tumor cells obtained from three cases of SCT showed papillary structures or rosette formations in part and demonstrated uniformly round to oval nuclei that contained finely granular chromatin, a fairly distinct nucleolus and a scant to moderate amount of granular or vesicular cytoplasm. Another case of SCT consisted of multinucleated giant cells with coherent chromatin as well as mononuclear cells with nuclear grooves. Islet cell tumor consisted mainly of clustered or isolated uniform mononuclear cells with rosette formations but without a papillary structure and occasional multinucleated giant cells in all cases. The nuclei of islet cell tumors had peculiar, fine chromatin aggregates with a "salt-and-pepper" appearance and slightly enlarged nucleoli. CONCLUSION: SCT is cytologically distinguishable from islet cell tumor in spite of having many cytologic features in common with it.

Adenoma, Islet Cell↗
PubMedDate not supplied

Rhabdomyosarcoma of the urachus. A case report.

BACKGROUND: Rhabdomyosarcoma of the urachus is extremely rare, and only two cases have been reported. Cytologic, histologic, immunochemical and electron microscopic findings in embryonal rhabdomyosarcoma of the urachus are presented. CASE: Embryonal rhabdomyosarcoma of the urachus developed in a 2-year-old boy. Imprint smears prepared prior to a histologic examination for a rapid report contained many malignant cells isolated or in clusters in a myxoid background. They were uniformly small, with round to oval nuclei and scant cytoplasm, and immunohistochemically positive for desmin and alpha-sarcomeric muscle actin but negative for myoglobin. This tumor was diagnosed cytologically as embryonal rhabdomyosarcoma because of its skeletal muscle origin and because of its similarity to one of the so-called small round cell tumors of childhood. Histologic examination confirmed the cytologic diagnosis. CONCLUSION: Cytologic, histologic and electron microscopic findings were identical to those described previously for embryonal rhabdomyosarcoma at other sites. In immunochemical examinations, cytologic samples fixed in ethanol are more useful than histologic ones fixed in formalin. Then, in order to differentiate poorly differentiated rhabdomyosarcoma from other small round cell tumors in children, desmin and alpha-sarcomeric actin, rather than myoglobin, are recommended.

Actins↗
PubMedDate not supplied

Primary and metaplastic choriocarcinoma of the bladder. A report of two cases.

Two cases of primary choriocarcinoma arose in the urinary bladder in males aged 72 and 70 years. Human chorionic gonadotropin (hCG) in serum and urine was significantly elevated in both cases. Cytologic features consisted of bizarre mononucleate and multinucleate giant cells with numerous erythrocytes, necrotic cells and neutrophils, indicating the possibility of choriocarcinoma. Histologically, one tumor consisted of an admixture of choriocarcinomatous areas and transitional cell carcinoma (TCC) with or without syncytiotrophoblastic differentiation, and the other was composed of pure choriocarcinoma. Immunohistochemical examination revealed that syncytiotrophoblasts and a small number of TCC cells were intensely positive for hCG in their cytoplasm. The histogenesis of choriocarcinoma arising in the bladder is considered to be metaplasia or retro-differentiation from TCC to trophoblasts because of TCC's differentiating to hCG-positive trophoblasts, as seen in one of the present cases.

Aged↗
PubMedDate not supplied

Pulmonary blastoma. A case report.

Pulmonary blastoma occurred in a 71-year-old man. Bronchial brushing specimens showed numerous epithelial cells and only a few mesenchymal cell clusters. The epithelial cells were round to oval, more uniform and smaller than ordinary adenocarcinoma cells. The nuclear:cytoplasmic ratio of these cells was increased, with an even chromatin distribution, and nucleoli were inconspicuous. Mesenchymal cell clusters were markedly hypercellular and consisted of small and short spindle-shaped cells with hyperchromatic nuclei. Although it is very difficult to diagnose pulmonary blastoma correctly by cytology, the possibility of pulmonary blastoma should be considered when small, nonsquamous neoplastic cells are observed, particularly in association with small and short spindle-shaped cells reminiscent of mesenchymal origin.

Aged↗