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Biomedical subjects

Y Sameshima

Publications and source records attributed to Y Sameshima.

At least 73 records · Page 4Linked to original sources
PubMed1986

[Adenocarcinoma arising in congenital dilatation of the intrahepatic bile duct].

A multilocular lesion was found in the left lobe of the liver in a 70-year-old woman who had complained of jaundice, fever and tumor of epigastrium. There was a continuous and branching cystic lesion in the resected left lobe of the liver diffusely, and communication with the right hepatic duct and the extrahepatic duct was recognized. These cystic spaces were filled with bile and mucus. The inside of the wall was covered with columnar epithelium showing papillay proliferation with marked mucin production. Furthermore, adenocarcinoma was demonstrated in multifoci surrounded by hyperplastic and dysplastic epithelium. This case was diagnosed as congenital dilatation of the intrahepatic bile duct accompanying adenocarcinoma.

Adenocarcinoma↗
PubMed1985

Clinical application of the measurement of serum asialoglycoproteins to estimate residual liver function in patients with chronic liver diseases with or without hepatocellular carcinoma.

The correlation between the amount of asialoglycoproteins and results of conventional liver function tests was studied in patients with chronic liver diseases, with or without hepatocellular carcinoma. The objective was to determine the clinical significance of the measurement of levels of serum asialoglycoproteins. The levels were elevated in accordance with the progress of liver diseases, and correlated with the decrease in albumin content, cholinesterase activity, the ratio of esterified cholesterol to total cholesterol and to the increase of indocyanine green retention at 15 min (p less than 0.001). There was no correlation with values of glutamic oxaloacetic and pyruvic transaminases. The amount of serum asialoglycoproteins also correlated with survival time in fatal cases of cirrhosis and/or hepatocellular carcinoma. Bilirubin and bile acids did not interfere with the measurement of serum asialoglycoproteins in cases of hyperbilirubinemia. Serum asialoglycoprotein levels are a good indicator of hepatic functional reserve in patients with chronic liver diseases, with or without hepatocellular carcinoma.

Asialoglycoproteins↗
PubMed1985

Release of hepatic mitochondrial ornithine transcarbamylase into the circulation in D-galactosamine-treated rats. Identification of serum ornithine transcarbamylase as the intact form of the mitochondrial enzyme.

A single injection of D-galactosamine into rats caused acute liver cell injury, and the activity of ornithine transcarbamylase in the serum increased about 600-fold as compared with that in the normal serum. Some properties of the serum enzyme from galactosamine-treated rats have been studied together with those of the mitochondrial enzyme in liver. Both the enzyme activities gave similar pH profiles, showing an optimum of pH 8.5. Apparent Km values of the serum enzyme for ornithine under the standard conditions at pH 7.4 and pH 7.7 were 1.59 mM and 0.94 mM, respectively, and those of the mitochondrial enzyme were 1.69 mM and 0.97 mM, respectively. The Km value of the serum enzyme for carbamyl phosphate was 0.34 mM, which is similar to that of the mitochondrial enzyme. The mitochondrial enzyme was purified 78-fold to homogeneity with a 45% yield by ammonium sulfate fractionation, heat treatment, 2nd ammonium sulfate fractionation, and phenyl-Sepharose CL-4B and CM-Sephadex C-50 column chromatographies. The specific activity of the purified enzyme was 282 mumol of citrulline formed per mg of protein per min at 37 degrees C. The mitochondrial and serum enzymes have a molecular weight of 115,000 as determined by Sephacryl S-300 gel filtration. Antibody specific for the mitochondrial enzyme was raised, and the immunological properties of the serum enzyme were examined. In immunoinhibition experiments, a decrease of the serum enzyme activity as well as the mitochondrial enzyme was observed on increasing the amount of the antibody.

Animals↗
PubMed1985

The effect of galactosamine on rat liver cytochrome P-450 activities.

The effect of galactosamine on hepatic drug metabolizing activities was examined in rats. In the microsomal fraction, the contents of cytochrome P-450 (P-450) and cytochrome b5 (b5) and the activity of NADPH-cytochrome c reductase (reductase) were examined for 7 days after galactosamine administration. In addition, substrate metabolizing activities in damaged microsomes were examined using four substrates: aminopyrine, aniline, benzo(a)pyrene (B(a)P) and 7-ethoxycoumarine (7-EC). The contents of P-450 and b5 and the activity of reductase showed a minimal value after 3 days of galactosamine administration and then gradually increased, reaching to the control level after 7 days. All four substrate metabolizing activities showed a similar response as the content of P-450, but the decrement among the four activities was not uniform. The activities of B(a)P hydroxylation and 7-EC deethylation were more impared than those of aminopyrine demethylation and aniline hydroxylation. This nonuniformity was clear on the activity based on P-450. This result suggested that galactosamine disturbed the population of multiple P-450 subtypes, and each P-450 subtype was damaged to the various extent by galactosamine administration.

Alanine Transaminase↗
PubMed1985

Changes in plasma amino acids during the oral glucose tolerance test and the effect of these changes on hepatic encephalopathy.

Changes in amino acid concentrations in plasma during a 100 g oral glucose tolerance test were investigated in patients with liver cirrhosis and in healthy controls. In the controls, almost all amino acid concentrations reached a nadir about 3 hours after glucose loading, then returned to initial levels after 6 hours. Immunoreactive insulin levels reached a peak about 30 minutes after loading, then decreased gradually, reaching initial levels after 6 hours. In the controls, the decrease ratios, defined as maximum decrease during the 3 hours after loading/initial concentration in plasma, were 0.607 and 0.554 for isoleucine (Ile) and leucine (Leu) respectively and 0.382 for valine (Val) which is significantly lower than for Ile or Leu. A similar tendency was recognized in patients with liver cirrhosis. The initial concentration of tyrosine (Tyr) and phenylalanine (Phe) in liver cirrhosis was significantly higher and their decrease ratios were significantly lower than in controls. Though no difference was observed between initial concentrations of tryptophan (Trp) in controls and liver cirrhosis patients, the decrease ratio of Trp in liver cirrhosis was lower (0.061) than that of controls (0.279) (p less than 0.001). The value, t-Trp/BCAA + AAA, i.e. total Trp concentration (mmol/l)/concentration (mmol/l) of branched chain amino acids (BCAA, Ile + Leu + Val) plus aromatic amino acids (AAA, Tyr + Phe), which is known to correlate with the brain Trp concentration of rats (Fernstrom, J. D. & Wurtman, R. J. (1972) Science 178, 414-416), changed significantly from 9.6 +/- 2.4 (mean +/- 1 SD) at the initiation to 12.9 +/- 3.3 at 3 hours after loading in controls (p less than 0.001), and in liver cirrhosis it changed from 10.3 +/- 1.9 to 15.8 +/- 3.1 (p less than 0.001).

Adult↗
PubMed1984

Endoscopical determination of gastric mucosal blood flow by the crossed thermocouple method.

A crossed thermocouple method in combination with endoscopy was applied to determine the blood flow rate of the human gastric mucosa. Determination was carried out with 11 healthy control subjects at 8 sites of the stomach. The blood flow rates at all sites in the corpus were found to be higher than those at the antrum. In subjects less than 50 years old the blood flow rate in the corpus was higher than in older subjects. These results were in agreed well with those obtained by the hydrogen gas clearance method, which is widely adopted clinically. The crossed thermocouple method is easily applicable to all sites in the gastric mucosa and the time required for the assay is very short. This method dose not require the inhalation of hydrogen gas which is necessary for the hydrogen gas clearance method and which is possibly harmful to humans. Although the values obtained by the crossed thermocouple method are relative to the value at a certain fixed site, this method will holds great potential for the determination of gastric mucosal blood flow rate.

Adult↗
PubMed1984

Determination of free tryptophan in plasma and its clinical applications.

Free tryptophan in plasma was separated by centrifugation through an Amicon ultrafiltration membrane cone. The value obtained without control of pH was found to be lower than that obtained with control of pH by an improved method ( Hijikata et al. (1981) Anal. Biochem. 118, 10-16). For determination of the total tryptophan concentration in the plasma, high performance liquid chromatography (HPLC) was better than the method of Denckla Dewey as modified by Bloxam & Warren ( (1974) Anal. Biochem. 60, 621-625), as judged on the basis of sensitivity, recovery rate and coefficient of variance. The total tryptophan concentration in the plasma determined by HPLC was lower than that determined by the Bloxam & Warren method. The total tryptophan concentration (t-Trp), free tryptophan concentration (f-Trp) and f-Trp/t-Trp ratio were 55.8 +/- 10.2 mumol/l, 11.6 +/- 1.5 mumol/l and 0.211 +/- 0.03 (mean +/- 1 SD) respectively, in healthy subjects (controls). No significant difference was observed between the values of controls and those of patients with liver cirrhosis, hepatocellular carcinoma, liver cirrhosis with hepatocellular carcinoma and hepatic encephalopathy of liver cirrhosis without bleeding. But in liver cirrhosis with bleeding, free tryptophan concentration (f-Trp, 48.0 +/- 23.3 mumol/l, p less than 0.001) and f-Trp/t-Trp ratio (0.645 +/- 0.289, p less than 0.001) were significantly higher than those of controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗
PubMed1984

Hyperasialoglycoproteinemia in patients with chronic liver diseases and/or liver cell carcinoma. Asialoglycoprotein receptor in cirrhosis and liver cell carcinoma.

The pathogenesis of hyperasialoglycoproteinemia in cirrhosis and liver cell carcinoma was investigated by measuring the amount of asialoglycoprotein receptor in hepatic tissues from 30 patients with either cirrhosis or a malignancy. The asialoglycoprotein receptor activity in the cirrhotic liver was 770 +/- 423 U/g liver, i.e., 28% of the control value (2770 +/- 731 U/g liver). Receptor activity was negligible in tissues from patients with either liver cell carcinoma or metastatic tumor. The receptor levels in noncirrhotic and cirrhotic tissues in close proximity to liver cell carcinoma were 2281 +/- 659 and 1134 +/- 473 U/g liver, respectively. There was a close correlation between serum asialoglycoprotein levels and the size of the tumor mass in patients with liver cell carcinoma. Our results suggest that decreases in the asialoglycoprotein receptor levels may lead to an accumulation of serum asialoglycoproteins in patients with cirrhosis or liver cell carcinoma, or both.

Asialoglycoprotein Receptor↗
PubMed1984

Hepatocellular carcinoma in the alcoholic.

The conversion of alcoholic hepatitis into cirrhosis and the eventual development of hepatocellular carcinoma (HCC) has been documented by serial biopsies in patients with uncomplicated alcoholism. Ethanol toxicity, nutritional deficiency and immunological abnormalities in a genetically predisposed individual appear to account for this sequence which can be accelerated by the hepatitis B virus and other noxious agents. Immune deficiency in malnourished alcoholics with liver disease diminishes response to the hepatitis B vaccine and may contribute to the development of HCC. Antigenic moieties in Mallory bodies appear to contribute directly to cytotoxicity and fibrosis in alcoholics, and may act like proto-oncogens. Available Mallory-body-specific monoclonal antibodies will hopefully facilitate diagnosis and treatment. Studies of DNA and collagen synthesis by in vitro perfusion of percutaneous liver biopsies provide information on precursor lesions of HCC. Abstinence, nutrient therapy and drug-induced anabolism lead to repair of liver damage and correction of immunological abnormalities, both of which may contribute to development of HCC in alcoholics with cirrhosis.

Carcinoma, Hepatocellular↗
PubMed1982

Egg yolk-induced lipolysosome proliferation and fat infiltration of rat liver.

The contribution of subcellular organelles in egg yolk-induced fatty liver was investigated in liver tissue sections and fractionated liver homogenates. When 2.0 ml. of 12.5 per cent egg yolk were administered to Wistar male rats (body weight, 250 to 350 gm.), a fatty change occurred in the liver after a 4-hour period. The acute fatty liver was characterized by intralysosomal accumulations of fat. The number of fat-containing lysosomes increased as early as 30 minutes after egg yolk administration. During this period, fat infiltration was not evident elsewhere in the cytoplasm. The increase of these lysosomes in tissue sections coincided with a selective proliferation of lipolysosomes in the heavy subfraction of floating lipids of liver homogenate. Neither Golgi-derived dense bodies of very low density lipoproteins nor vesicles of the endoplasmic reticulum increased in number throughout the experimental period. These observations indicate that hepatic lysosomes are involved in the degradation of exogenous cholesterol and that transformation of lysosomes to lipolysosomes is a direct result of cholesterol overload and not simply a manifestation of fatty liver.

Animals↗