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T Ichida

Publications and source records attributed to T Ichida.

At least 109 records · Page 6Linked to original sources
PubMed1992

Tenascin expression in human chronic liver disease and in hepatocellular carcinoma.

Tenascin is an oligomeric glycoprotein of the extracellular matrix synthesized during embryonic development. It is prominently expressed in a variety of tumors. The role of tenascin in liver tissue is, however, unknown. We used immunocytochemistry to define the localization of tenascin and compare this with the localization of non-collagenous proteins, such as laminin and fibronectin, in normal human liver and pathological liver from patients with chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. In normal liver, tenascin expression was localized along the sinusoidal and vascular wall. In fibrotic liver, tenascin was also observed in the region between the hepatic parenchyma and the fibrosing portal tracts, especially in areas of piecemeal necrosis in chronic hepatitis. Immuno-EM study of liver tissue in chronic hepatitis strongly suggested the synthesis and secretion of tenascin by fat-storing cells into the space of Disse. In hepatocellular carcinoma, tenascin was expressed in both the capsule and lobular septa, but not in the sinusoidal walls of the tumors. These results led us to postulate a close relationship between the occurrence of this protein and disease processes such as fibrosis and cancer invasion.

Carcinoma, Hepatocellular↗
PubMed1991

Okadaic acid inhibits amylase exocytosis from parotid acini stimulated by cyclic AMP.

To evaluate the role of protein phosphorylation in amylase exocytosis, we studied the effects of okadaic acid, a potent inhibitor of protein phosphatase types 1 and 2A, on amylase release and protein phosphorylation in rat parotid acini. Although okadaic acid by itself weakly stimulated amylase release, it did not potentiate amylase release stimulated by half-maximum doses of isoproterenol or cAMP, and markedly inhibited their maximum effects. Okadaic acid dose-dependently increased cAMP-independent phosphorylation of some proteins and enhanced cAMP-dependent phosphorylation of 21- and 26-kDa proteins. These results indicate that increase in protein phosphorylation does not necessarily enhance the exocytosis of amylase from parotid acini.

Amylases↗
PubMed1991

Cyclic AMP antagonist Rp-cAMPS inhibits amylase exocytosis from saponin-permeabilized parotid acini.

Rp-cAMPS, the Rp-diastereomer of adenosine 3',5'-phosphorothioate, is often referred to as a cAMP antagonist, since it binds to the regulatory subunit of cAMP-dependent protein kinase without dissociation of free catalytic subunits. To evaluate the role of cAMP-dependent protein kinase in amylase exocytosis, we examined the effect of Rp-cAMPS on amylase release from rat parotid acini. Rp-cAMPS did not stimulate amylase release from saponin-permeabilized parotid acini, whereas its Sp-isomer strongly evoked amylase release. Rp-cAMPS dose-dependently inhibited amylase release stimulated by Sp-cAMPS. In the presence of Rp-cAMPS, the dose-response curve of Sp-cAMPS was shifted to the right. The inhibitory effect of Rp-cAMPS on isoproterenol-induced amylase release was not detected in intact acini, but was clearly observed in the permeabilized ones. Rp-cAMPS markedly inhibited protein phosphorylation evoked by Sp-cAMPS, indicating that Rp-cAMPS prevents the dissociation of cAMP-dependent protein kinase. These results, taken together with synergistic increase in amylase release by the combination of site-selective cAMP analogues [T. Takuma (1990) J. Biochem. 108, 99-102], suggest that cAMP-dependent protein kinase is involved in the exocytosis of amylase from parotid acini.

Amylases↗
PubMed1991

Roles of potassium and chloride ions in cAMP-mediated amylase exocytosis from rat parotid acini.

The roles of potassium and chloride ions in cAMP-mediated amylase exocytosis were studied using intact and saponin-permeabilized parotid acini. Cyclic AMP-evoked amylase release from saponin-permeabilized parotid acini decreased markedly when KCl in the incubation medium was isoosmotically replaced by K-glutamate, NaCl, Na-isothionate, or mannitol. Quinidine and barium, K+ channel blockers, clearly inhibited amylase release from the permeabilized acini, but not from intact ones. The chloride channel blocker DPC (diphenylamine-2-carboxylate) also inhibited amylase release, while DIDS (4,4'-diisothiocyanostilben-2,2'-disulfonate) or bumetanide had little effect, if any, on the exocytosis. Hyperosmolarity with mannitol markedly reduced amylase release from permeabilized acini. These results suggest that potassium and chloride ions play important roles in cAMP-mediated amylase exocytosis, and that these ions act on secretory granules inside the acinar cells.

Amylases↗
PubMed1990

One-step sandwich enzyme immunoassay for human laminin using monoclonal antibodies.

A one-step sandwich enzyme immunoassay (one step sandwich EIA) for human serum immunoreactive laminin was set up with a pair of monoclonal antibodies prepared against human placental laminin P1 fragment. The assay was characterized by carrying out two immunoreactions simultaneously, laminin P1 fragment reacting with both a monoclonal antibody as a solid phase and a horseradish peroxidase-labeled monoclonal antibody (Fab') against human laminin P1 fragment as conjugate. Sensitivity of the immunoassay was 0.01 ng/well (0.5 microgram/l), and linearity was obtained between 0.01-20 ng/well (0.5-1,000 micrograms/l). The levels of laminin in sera from normal individuals and patients with liver cirrhosis, hepatocellular carcinoma and primary biliary cirrhosis were 103 +/- 15 micrograms/l, 228 +/- 70 micrograms/l, 341 +/- 163 micrograms/l and 232 +/- 93 micrograms/l, respectively. Protein immunoblotting showed that the serum immunoreactive laminin measured by the assay was a fragment with rel mol mass of 200 kDa.

Antibodies, Monoclonal↗
PubMed1990

Toxicological studies on a benzofurane derivative. II. Demonstration of peroxisome proliferation in rat liver.

The uricosuric drug benzbromarone (3,5-dibromo-4-hydroxyphenyl)-1-(2-ethyl-3-benzofuranyl)methanone, a benzofurane derivative, was studied for its effects on parameters related to hepatic peroxisome proliferation. Groups of male F-344 rats were fed either basal diet, the peroxisome proliferator clofibrate at 5000 ppm as a comparison compound, or benzbromarone at two doses, 1000 and 2000 ppm. Benzbromarone and clofibrate produced hepatomegaly and increases in the activities of catalase, acyl CoA oxidase, malate dehydrogenase, and glycerol-3-phosphate dehydrogenase. Benzbromarone and clofibrate also both induced similar histologic and ultrastructural changes in hepatocytes, including induction of peroxisomes. Therefore, benzbromarone acted as a peroxisome-proliferating agent in rats under these conditions. Benzbromarone differs from other peroxisome proliferators in its chemical structure, uricosuric action, and the morphology of liver peroxisomes that were induced by exposure.

Animals↗
PubMed1990

Subcellular abnormalities of liver sinusoidal lesions in human hepatocellular carcinoma.

Liver sinusoidal lesions in 20 cases of human hepatocellular carcinoma (HCC) were examined with the electron microscope. Kupffer cells existed in the compact type of HCC. In area with pseudoglandular and trabecular cell patterns, Kupffer cells could not be observed. Only a few macrophages were distributed in the tumor tissues. Endothelial cells were altered and showed a poly-layered arrangement and were attached to each other with desmosome-like junctional complexes. There was a general loss of endothelial fenestrae. Endocytotic vesicles could be recognized in these endothelial cells. Poly-layered endothelial cells and accompanying layers of basal laminae were variably arranged between sinusoids and tumor cells with pseudoglandular, trabecular, or compact types of tumor cell patterns. Atypical cells containing numerous lysosomes, together with altered fat-storing (Ito) cells, were located in the tissue space bordering the capillaries. Moreover, tumor cells possessed flattened sinusoidal surfaces. These alterations of the sinusoidal wall suggest that capillarization of liver sinusoids in HCC took place, by loss of fenestrations, formation of basal laminae, and loss of microvilli on the surface of tumor cells. These architectural alterations are thought to completely change the physiological pattern of exchange of metabolites between tumor cells and the sinusoidal lumen. The absence of large numbers of Kupffer cells suggests that at this stage of tumor development, local cellular defense mechanisms were inoperative.

Basement Membrane↗
PubMed1989

One step sandwich enzyme immunoassay for human type IV collagen using monoclonal antibodies.

Monoclonal antibodies were used in one step sandwich enzyme immunoassay (one step sandwich EIA) for human serum immunoreactive type IV collagen. The one step sandwich EIA using either polystyrene ball or microplate was characterized by carrying out two immunoreactions simultaneously, type IV collagen reacting with both a monoclonal antibody as a solid phase and a horseradish peroxidase-labeled monoclonal antibody (Fab') against human type IV collagen as a conjugate. Sensitivity of one step sandwich EIA system by using either polystyrene ball or microplate was 0.22 ng per tube or 0.04 ng per well for type IV collagen, and linearity was obtained between 0.22-40 ng/tube or 0.04-20 ng per well, respectively. Both methods gave reproducible quantitative analysis of immunoreactive type IV collagen levels in the sera of patients with hepatocellular carcinoma and patients with liver cirrhosis, which were apparently higher than the levels in the sera of healthy subjects. Protein immunoblotting shows that the immunoreactive type IV collagen trapped in our present one step sandwich EIA system was not the 7-S and NC1 domains of type IV collagen.

Antibodies, Monoclonal↗
PubMed1989

Treatment of hepatocellular carcinoma utilizing lymphokine-activated killer cells and interleukin-2.

This paper is a report on adoptive immunotherapy involving consecutive injections of recombinant interleukin-2 and lymphokine-activated killer (LAK) cells in the treatment of hepatocellular carcinoma. Peripheral blood lymphocytes, obtained by leukopheresis, acted as the activated killer cells with a co culture of recombinant interleukin-2 in the culture system. After 4 days, the activated killer cells were returned into the patients' bodies intra-arterially and intravenously. No complete remissions or partial remissions have resulted, although five of the seven patients showed a significant decrease in their serum alpha-fetoprotein levels after treatment. In addition, one case showed a patent portal truncus while another indicate the appearance of central necrosis on the computerized tomograph scan. Although the period of observation was short, there were no recurrences after the combination therapy of tumor resection and LAK adoptive immunotherapy. It might be difficult to treat hepatocellular carcinoma with adoptive immunotherapy alone, but there is some possibility of conducting therapy for hepatocellular carcinoma after removing the majority of the tumor cells by surgical resection and transcatheter arterial embolization therapy. This conclusion indicates, at least theoretically, that adoptive immunotherapy will be suitable in the treatment of hepatocellular carcinoma as one of the combination therapies with the two major forms of treatment mentioned above.

Adult↗
PubMed1989

A new human cholangiocellular carcinoma cell line (HuCC-T1) producing carbohydrate antigen 19/9 in serum-free medium.

A human cholangiocellular carcinoma cell line, HuCC-T1, was established in vitro from the malignant cells of ascites of a 56-yr-old patient. Histologic findings of the primary liver tumor revealed a moderately differentiated adenocarcinoma. Tumor cells from the ascites have been cultured with RPMI 1640 medium containing 0.2% lactalbumin hydrolysate and the cultured cells grew as monolayers with a population doubling time of 74 h during exponential growth at Passage 25. They had an epithelial-like morphology and were positive for mucine staining. Ultrastructural studies revealed the presence of microvilli on the cell surface and poorly developed organelles in the cytoplasm. The HuCC-T1 cell was tumorigenic in nude mice. The number of chromosomes in HuCC-T1 ranged from 61 to 80. These human cholangiocellular carcinoma cells in serum-free medium secreted several tumor markers, including carbohydrate antigen 19/9, carbohydrate antigen 125, carcinoembryonic antigen, and tissue polypeptide antigen. The carbohydrate antigen 19/9 secretion level of HuCC-T1 cells cultured in RPMI 1640 medium with 1% fetal bovine serum was sixfold higher than that with 0.2% lactalbumin hydrolysate. These findings suggest that HuCC-T1 will provide useful information to clarify the mechanism of tumor marker secretion and tumor cell growth in the human cholangiocellular carcinoma.

Adenoma, Bile Duct↗
PubMed1989

[An attempt of in vitro portal invasion model of hepatocellular carcinoma utilizing permeable collagen membrane].

Hepatocellular carcinoma (HCC) possessed the ability of vascular invasiveness toward hepatic portal vein on the process of progression. This biological character of HCC can influence the patients survival on clinically. In this paper, we tried to establish the in vitro portal invasion model with human materials. The hepatic portal vein endothelial cell (HPVEC) derived from intrahepatic portal veins by surgically, have been propagated, as outgrowth cultures in RPMI-1640 medium with 10% fetal bovine serum, on permeable collagen membranes (KOKEN, Tokyo) containing mainly type I collagen, covered with a solubilized tissue basement membrane (MATRIGEL, Collaborate Res., Inc., Bedford MA) involving type IV collagen, laminin and proteoglycan. The primary cultured HPVEC with polygonal shaped cells forming a pavement stone sheet, were positively stained with Factor VIII related antigen and synthesized both prostacyclin and collagenase inhibitor. Co-culture of primary human HPVEC and HuH-7 (human HCC cell line obtained from Prof. Satoh, Okayama Univ.,) cells were inoculated onto reverse side between collagen membrane and gell formed basement membrane. Morphological alterations on the side of HPVEC can be obtained such as polylayered cells and different cytoplasmic cells among HPVEC. These results indicate that this experimental model can provide an useful in vitro model for the study of HCC portal invasion.

Carcinoma, Hepatocellular↗
PubMed1989

[Effect of anterior-lateral mandibular displacement occurring in lateral roentgenocephalometry at the open mouth position on the linea measurements].

The present study was undertaken to determine the effect of mandibular displacement occurring in lateral roentgenocephalometry at the open mouth position and of the resulting changes in the projected sites on linea measurements of the mandible. With use of a brachicephalic young (corresponding to age 7) and a dolichocephalic adult human dried mandible, lateral roentgenocephalograms taken under different conditions with angles and distances varied, simulating clinical lateral roentgenocephalometry at the open mouth position, were compared and studied. The results were as follows: 1. Displacement from 5 mm to 30 mm perpendicular to the central X-ray caused unfixed changes, presumed to be human errors in measuring, in the following ranges; brachicephaly: 0-1.4%, dolichocephaly: 0-0.9%. 2. As angles of rotation perpendicular to the central X-ray increase from 0 to 10 degrees clockwise, significant reduction in inverse proportion to the increase in angles of rotation were found; Cd-Gna: brachicephaly: 1.3%, dolichocephaly: 0.9-1.4%; Go-Gna: brachicephaly: 1.6-3.3%, dolicocephaly: 1.4-2.2%. However, unfixed changes in the following ranges were found for Cd-Go; brachicephaly: 0.5-2.3%, dolicocephaly: 0.6-1.2%. 3. Increase in angles of rotation counterclockwise also showed a similar tendency to that in clockwise rotation.

Adult↗
PubMed1988

Induction of hepatic peroxisome proliferation in mice by lactofen, a diphenyl ether herbicide.

A technical grade of lactofen (1'[carboethoxy]ethyl 5-[2-chloro-4-[trifluoro-methyl] phenoxy]-2-nitrobenzoate) has been shown to induce liver tumors in mice. To determine a possible mechanism of action, the effect of exposure for 7 weeks to dietary concentrations of 2, 10, 50, and 250 ppm technical grade lactofen and 250 ppm of pure lactofen was studied for various liver parameters in groups of male and female CD-1 mice. Liver-weight to body-weight ratio, liver catalase, liver acyl-CoA oxidase, liver cell cytoplasmic eosinophilia, nuclear and cellular size, and peroxisomal staining were increased by the tumorigenic dose of lactofen, i.e., 250 ppm, in a fashion similar to the comparison chemical nafenopin (500 ppm), which is a peroxisome proliferator. Lower doses of lactofen that were reported as nontumorigenic had little or no effect on these parameters. Thus, pure and technical grade lactofen appear to induce murine liver tumors through a mechanism similar to epigenetic hepatocarcinogens of the peroxisome proliferating type.

Acyl-CoA Oxidase↗
PubMed1988

Amylase secretion from saponin-permeabilized parotid cells evoked by cyclic AMP.

Adenosine 3',5'-monophosphate (cAMP) evoked amylase release from saponin-permeabilized parotid cells of the rat. Saponin concentration was optimal at 10 micrograms/ml. Amylase release was stimulated by cAMP almost as well in Ca2+-free medium containing 1 mM EGTA as in the medium containing a physiological concentration of calcium. Although the basal and stimulated releases of amylase were markedly reduced by the further addition of 5 mM EGTA, the effect of cAMP was still detectable. The half-maximal dose of cAMP was 0.3 mM, whereas those of dibutyryl cAMP and 8-bromo-cAMP were 10-fold lower than that of cAMP. In the presence of 10 microM 3-isobutyl-1-methylxanthine, the half-maximal dose of cAMP was also decreased by 5-fold. These results suggest: 1) intracellular calcium is not essential for the exocytosis of amylase stimulated by cAMP; 2) the responsiveness of the cells to exogenous cAMP is reduced by phosphodiesterase.

1-Methyl-3-isobutylxanthine↗
PubMed1988

[Effects of various factors on the growth and function of a human hepatoblastoma cell line, HuH-6--an approach for serum-free cell culture].

The effects on a human hepatoblastoma cell line (HuH-6) of serum and Ca2+ were investigated. A higher concentration of serum reduced the production of alpha-fetoprotein, whereas Ca2+ enhanced that of both albumin and alpha-fetoprotein. In view of these facts, a serum-free medium using RPMI-1640 supplemented with lactalbumin hydrolysate, epidermal growth factor, hydrocortisone, insulin, chrelatoxine, glucagone and selenium was then developed. Collagen type IV was superior to collagen type I, laminin, fibronectin and plastic in supporting the growth of HuH-6 in the serum-free medium. Higher amounts of both albumin and alpha-fetoprotein were secreted in HuH-6 cultured in serum-free medium than in serum-supplemented medium.

Blood↗
PubMed1988

Clinical evaluation of transcatheter arterial embolization and one-shot chemotherapy in hepatocellular carcinoma.

The therapeutic effect and the prognosis of transcatheter arterial embolization (TAE) and one-shot chemotherapy were studied in 90 cases of unresectable hepatocellular carcinoma (HCC). A therapeutic effect, which was assessed by the serum concentration of alpha-fetoprotein, angiography, computed tomography and ultrasonography, was seen in 33 (83%) out of 40 cases treated with TAE, and in 16 (32%) out of 50 cases treated with one-shot chemotherapy. In the cases that received TAE, the cumulative percentage survival rates at 6 months, 12 months, and 24 months were 75%, 48% and 20%, respectively. In contrast, the survival rates in the cases that received one-shot chemotherapy were 30%, 10% and 2%, respectively. In addition, the prognosis on the basis of the degree of tumor invasion of the portal vein was studied. In cases with the same degree of tumor invasion, the survival rate of the cases treated with TAE was significantly higher than that of those treated with one-shot chemo-therapy, except for those cases with tumor invasion of the main portal vein. These results show that TAE should be performed as the therapy of first choice in unresectable cases of HCC.

Carcinoma, Hepatocellular↗