Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The use of a hyaluronic acid-binding proteoglycan (hyaluronectin) as a probe for the detection of hyaluronic acid has facilitated the development of an indirect enzymo-immunological assay for hyaluronidase. Plastic microtest ELISA plates were coated with hyaluronic acid. Incubation with hyaluronidase led to the destruction of insolubilized hyaluronic acid in proportion to the hyaluronidase concentration of samples. Residual hyaluronic acid was assayed by its capacity to bind immune complexes made up of hyaluronectin supplemented with alkaline phosphatase-conjugated anti-hyaluronectin antibodies. The technique was very sensitive and permitted the detection of as little as 10(-10) NFU of bovine testicular hyaluronidase. Hyaluronidase was detected by this technique in human sera, bee venom and culture medium of human hepatoma cell lines.
 ...
PMID:An indirect enzymoimmunological assay for hyaluronidase. 331 96

In order to evaluate geographical differences in the liver pathology of ducks infected with duck hepatitis B virus (DHBV), ducks in Chiba and Shimane, Japan, and Shanghai, China, were investigated. The numbers (DHBV positive/negative) and the maximum age of the ducks examined were 18/10 at 19 mo, 15/1 at 3 yr 4 mo, and 72/27 at 18 mo, respectively. DHBV infection was induced experimentally in ducks from Chiba and Shimane but was present congenitally in those from Shanghai. Ducks were examined regarding liver function tests, conventional histology, immunohistology, electron microscopy, and molecular hybridization for DHBV DNA in the serum and liver. There was no significant difference between DHBV-positive and -negative ducks in bilirubin and transaminase and alkaline phosphatase activities in the sera. Histologically, while the livers of ducks from Chiba and Shimane did not show necroinflammatory (hepatitis) activity, those from Shanghai frequently did (52.5%). Necroinflammatory activity of the Shanghai ducks was present almost equally in both DHBV-positive and -negative livers. The livers of Shanghai ducks but not the other two areas often (8.3%) had ground-glass inclusions which corresponded ultrastructurally to numerous virus particles in the dilated cisternae of the proliferated endoplasmic reticulum. No advanced liver disease, such as cirrhosis or hepatocellular carcinoma, was observed. There was no significant difference in the amount of DHBV DNA in the sera or in its pattern in the liver tissue among ducks of the three areas. In addition, the livers of Chiba ducks frequently had amyloidosis, while those of Shanghai ducks were contaminated with parasites. In conclusion, DHBV infection did not appear to provoke significant hepatitis activity or advanced liver disease in the examined ducks of all three areas, and the DHBV-positive livers from Shanghai ducks showed a different morphological appearance from those of the other two areas. This variation might reflect the difference in the strain of ducks, subtypes of DHBV, environmental factors, or a combination of these influences.
 ...
PMID:Geographical pathology of duck livers infected with duck hepatitis B virus from Chiba and Shimane in Japan and Shanghai in China. 334 10

When a rat hepatoma cell (R-Y121B) homogenate was incubated at 37 degrees C, 30-70% of the total alkaline phosphatase was released into the supernatant fluid from the precipitate fractions. The release reached a plateau level after 10 h of incubation at 37 degrees C. The optimum pH value for the release was 7.4. Alkaline phosphatase activity increased during the incubation of the cell homogenates, but this increase was independent of the enzyme release. Serum increased not only alkaline phosphatase activity in the cultured cells but also enzyme release in their homogenates. In addition, we examined a rat liver homogenate and the following 11 cell lines: 3 hepatoma cell lines, including the R-Y121B cell line, 4 liver cell lines, 2 human urinary bladder carcinoma cell lines, a kidney cell line, and a mouse adrenal tumor cell line. Only in the cultured liver cell line and hepatoma cell lines, 30-60% of the total enzyme was released into the soluble fraction from the precipitate fractions; the release was not observed in the other cell lines, nor in the rat liver homogenate. The release of alkaline phosphatase took place in both heat-stable and heat-labile alkaline phosphatases. Alkaline phosphatase, extracted from cell homogenates, showed two bands during polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The mobilities of the two bands changed inversely with or without sodium dodecyl sulfate. In general, the alkaline phosphatase which showed slow mobility with sodium dodecyl sulfate was more readily released from the plasma membrane.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:The autorelease of alkaline phosphatase from the plasma membrane during the incubation of cultured liver cell homogenates. 336 Jul 60

A prospective study identified 45 patients with malignancy-related ascites among 448 ascites patients (10% of the total). Patients were categorized into five subgroups based on the pathophysiology of ascites formation. Each subgroup had a distinctive ascitic fluid analysis. Patients with peritoneal carcinomatosis but without massive liver metastases (53.3% of the patients with malignancy-related ascites) had a uniformly positive ascitic fluid cytology, high ascitic fluid protein concentration and low serum-ascites albumin gradient. Patients with massive liver metastases and no other cause for ascites formation (13.3% of the series) had a negative cytology, low ascitic fluid protein concentration, high serum-ascites albumin gradient and markedly elevated serum alkaline phosphatase. Those with peritoneal carcinomatosis and massive liver metastases (13.3% of the series) had a nearly uniformly positive ascitic fluid cytology, variable protein concentration, high serum-ascites albumin gradient and markedly elevated serum alkaline phosphatase. Chylous ascites (6.7%) was characterized by a milky appearance, negative cytology and an elevated ascitic fluid triglyceride concentration. Patients with hepatocellular carcinoma superimposed on cirrhosis (13.3%) had negative ascitic fluid cytology, low ascitic fluid protein concentration, high serum-ascites albumin gradient and elevated serum and ascitic fluid alpha-fetoprotein concentration. Two-thirds of patients with malignancy-related ascites had peritoneal carcinomatosis; 96.7% of patients with peritoneal carcinomatosis had positive ascitic fluid cytology. Ascitic fluid analysis is helpful in identifying and distinguishing the subgroups of malignancy-related ascites.
 ...
PMID:Ascitic fluid analysis in malignancy-related ascites. 341 31

We developed a method for selective preparation of two forms of alkaline phosphatase from rat tissues. The enzyme was extracted by n-butanol treatment at pH 5.5 and pH 8.5 as soluble and aggregated (membranous) forms, respectively. The soluble form prepared from liver was found to be identical with the serum enzyme. Complete solubilization of the membrane-bound enzyme without detergents had a great advantage in its purification. Rat hepatoma AH-130 cells enriched in alkaline phosphatase were first used for purification of the liver-type enzyme. The hepatoma enzyme, purified by chromatographies on concanavalin-A-Sepharose, Sephacryl S-300 and hydroxyapatite was used for production of antibodies specific for the liver-type isozyme. An immunoaffinity column, prepared with anti-(hepatoma-enzyme) IgG was utilized for the enzyme purification from other tissues including the membranous form. Analyses of amino acid composition of the purified enzymes revealed that all the liver-type enzymes from hepatoma, liver, kidney and serum had the same composition, whereas the intestinal type consisted of the composition distinctly different from that in the liver type. In addition, there was no significant difference in amino acid composition between the soluble and membranous forms, suggesting a possible involvement in the membranous form of a hydrophobic component other than its polypeptide domain. The present method for selective preparation of the soluble and membranous forms of alkaline phosphatase will be useful for a further investigation on the interaction of the enzyme with membranes.
 ...
PMID:Selective preparation and characterization of membranous and soluble forms of alkaline phosphatase from rat tissues. A comparison with the serum enzyme. 376 22

In Reuber rat hepatoma cells (R-Y121B), alkaline phosphatase activity increased without de novo enzyme synthesis (Sorimachi, K., and Yasumura, Y. (1986) Biochim. Biophys. Acta 885, 272-281). The enzyme was partially purified by butanol extraction from the particulate fractions. The incubation of the extracted alkaline phosphatase with the cytosol fraction induced a large increase in enzyme activity (5-10-fold of control). The dialyzed cytosol was more effective than the undialyzed cytosol during an early period of incubation at 37 degrees C. This difference between the dialyzed and the undialyzed cytosol fractions was due to endogenous Na+. For maximal activation of the enzyme, both Mg2+ above 1 mM and Zn2+ at low concentrations (below 0.01 mM) were needed, although Zn2+ at high concentrations (above 0.1 mM) showed an inhibitory effect. Zn2+ and Mg2+ alone slightly increased alkaline phosphatase activity. This activation of the enzyme was temperature dependent and was not observed at 0 or 4 degrees C. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate showed that the increase in alkaline phosphatase activity did not involve the fragmentation of the enzyme and that 65Zn2+ bound to it during enzyme activation with 65Zn2+ and Mg2+. The cytosol fraction not only supplied Zn2+ to the nascent enzyme but also increased the maximal enzyme activity more than did direct addition of metal ions. Ferritin and metallothionein contributed to the activation of alkaline phosphatase with the metal ions. Since the binding of Zn2+ and Mg2+ to the nascent alkaline phosphatase is disturbed in Reuber rat hepatoma cells (R-Y121B), the apoenzyme is accumulated inside the cells. The binding of Zn2+ and Mg2+ to the apoenzyme readily takes place in the cell homogenates accompanied by an increase in catalytic activity without new enzyme synthesis.
 ...
PMID:Activation of alkaline phosphatase with Mg2+ and Zn2+ in rat hepatoma cells. Accumulation of apoenzyme. 380 40

Oval cells isolated from livers of rats fed a choline-deficient diet containing 0.1% DL-ethionine (CDE) have an alkaline phosphatase (ALKP) isozyme which can be distinguished by its electrophoretic mobility from the enzyme present in parenchymal cells isolated from normal liver or livers of rats fed the CDE diet for 4 weeks. The oval cell ALKP has the same electrophoretic mobility as the enzyme from fetal rat liver and placenta. ALKPs from oval cells, parenchymal cells, and placenta all differ from the intestinal enzyme by their electrophoretic mobility, isoelectric focusing, and the patterns of amino acid inhibition of enzyme activity. Oval cells in preneoplastic livers, fetal hepatocytes, and tumor cells of a primary hepatocellular carcinoma induced by CDE feeding stained with a monoclonal antibody directed against rat placental ALKP. Hepatocytes (in normal or preneoplastic livers) and bile duct cells in normal liver did not stain with the same antibody. Placental ALKP may thus be a useful marker in tracing the origin and fate of oval cells during hepatocarcinogenesis.
 ...
PMID:Oncodevelopmental expression of rat placental alkaline phosphatase. Detection in oval cells during liver carcinogenesis. 390 68

The phosphorylation characteristics of insulin receptor from control and insulin-treated rat H-35 hepatoma cells 32P-labeled to equilibrium have been documented. The 32P-labeled insulin receptor is isolated by immunoprecipitation with patient-derived insulin receptor antibodies in the presence of phosphatase and protease inhibitors to preserve the native phosphorylation and structural characteristics of the receptor. The unstimulated insulin receptor contains predominantly [32P] phosphoserine and trace amounts of [32P]phosphothreonine in its beta subunit. In response to insulin, the insulin receptor beta subunit exhibits marked tyrosine phosphorylation and a 2-fold increase in total [32P]phosphoserine contents. High pressure liquid chromatography of the tryptic hydrolysates of the 32P-labeled receptor beta subunit from quiescent cells results in the resolution of up to 9 fractions containing [32P]phosphoserine. The insulin-stimulated tyrosine phosphorylation is concentrated in two of these receptor phosphopeptide fractions, whereas the increase in [32P]phosphoserine content is scattered in low abundance over all receptor tryptic fractions. Insulin receptors affinity-purified by lectin- and insulin-agarose chromatographies from insulin-treated, 32P-labeled cells exhibit a 22-fold increase in the Vmax of receptor tyrosine kinase activity toward histone when compared to controls. The elevated kinase activity of the insulin receptor derived from insulin-treated cells is not due to the presence of hormone bound to the receptor because the receptor kinase activity is assayed while immobilized on insulin-agarose. Furthermore, the insulin-activated receptor kinase activity is reversed following dephosphorylation of the receptor beta subunit with alkaline phosphatase in vitro. The correlation between the insulin-stimulated site specific tyrosine phosphorylation on receptor beta subunit and the elevation of receptor tyrosine kinase activity strongly suggests that the insulin receptor kinase is activated by hormone-stimulated autophosphorylation on tyrosine residues in intact cells, as previously demonstrated for the purified receptor.
 ...
PMID:Tyrosine phosphorylation of insulin receptor beta subunit activates the receptor tyrosine kinase in intact H-35 hepatoma cells. 395 14

The clinical features of 77 patients with primary liver cell carcinoma seen over a nine-year period were examined. Eighty per cent of the patients had underlying cirrhosis, of alcoholic origin in most cases. In nine of the patients hepatitis B surface antigen was found in the serum; all nine patients were born in areas where hepatitis B virus infection is endemic. Abdominal pain and ascites were the most common presenting symptoms; they are due mainly to the locally invasive nature of the tumour. A confirmatory laboratory finding in the diagnosis is the observation of raised alkaline phosphatase levels and the presence of alpha-fetoprotein in the serum. The diagnosis should be established without performing a laparotomy and should seriously be considered in a previously stable patient with cirrhosis who deteriorates clinically without obvious cause.
 ...
PMID:Primary liver cell carcinoma. Clinical features. 396 17

Alkaline phosphatase released from rat liver plasma membrane under usual conditions was electrophoretically not identical with a soluble form in serum which was derived from the liver. The liver-membranous alkaline phosphatase, however, was converted to the serum-soluble form when the liver plasma membrane was treated with n-butanol under the acidic conditions lower than pH 6.5. Such pH-dependent conversion of the enzyme was not observed in plasma membrane of rat ascites hepatoma AH-130 cells. The converting activity for alkaline phosphatase was detected not only in plasma membrane but also in lysosomal membrane of rat liver.
 ...
PMID:pH-dependent conversion of liver-membranous alkaline phosphatase to a serum-soluble form by n-butanol extraction. 397 Jul 13


<< Previous 1 2 3 4 5 6 7 8 9 10