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Biomedical subjects

N Takei

Publications and source records attributed to N Takei.

At least 199 records · Page 11Linked to original sources
PubMed1984

Effects of branched-chain alpha-keto acids on plasma amino acid concentrations in carbon tetrachloride-intoxicated rats.

Plasma branched-chain amino acid levels during continuous intravenous infusion of sodium salts of branched-chain alpha-keto acid were much higher in CCl4-intoxicated rats than in control rats. However, increases after intragastric administration were diminished in both groups. Increased plasma alloisoleucine levels following administration of R,S-alpha-keto-beta-methylvaleric acid were reduced greatly by using only S-alpha-keto-beta-methylvaleric acid.

Amino Acids↗
PubMed1984

Purification and characterization of rat liver cytosol catalase.

Rat liver cytosol catalase was purified by making use of its interaction with deoxycholate and by the various methods used to purify peroxisomal catalase. The purified preparation was both enzymatically and immunologically identical with the purified peroxisomal catalase, but differed in its chromatographic behaviour and electrophoretic mobility. Amino acid analysis also revealed a slight difference between the two catalase molecules.

Amino Acids↗
PubMed1984

[Preparation of conjugates of adriamycin with antibodies to alpha-fetoprotein and their properties].

For its selective accumulation into tumor cells, the antitumor drug adriamycin (ADM) was attached to specific antibodies reactive against alpha-fetoprotein, a carcinoembryonic protein, and the antibody and antitumor activities of the resulting conjugate were investigated. Using the glutaraldehyde or carbodiimide binding methods, preparations containing 4-5 moles of ADM per mole of antibody were obtained. They retained 60-75% of the original antibody activity. Upon incubation of AH-66 ascites hepatoma cells with the conjugates, an increased number of dead cells and inhibited uptake of 3H-thymidine by the cells were observed. The conjugates were more effective against tumor cells than the free drug, and it was further presumed that the cytotoxic action of ADM on normal cells could be reduced by binding it to a macromolecular protein.

Animals↗
PubMed1983

Alterations in neutral amino acid transport across the blood-brain barrier in hepatic failure.

The accelerated transport of the blood neutral amino acids into the brain in encephalopathic patients with fulminant hepatitis and advanced liver cirrhosis was demonstrated not only by determining the cerebrospinal fluid (CSF) aminogram but also by calculating the predicted velocity of the amino acid transport through the blood-brain barrier. Significant elevation in CSF aromatic amino acid (AAA) and methionine levels was observed in the encephalopathic patients. Arousal from hepatic encephalopathy by drip infusion of a branched chain amino acid (BCAA)-enriched solution was obtained coincidentally with the elevated BCAA levels and diminished concentrations of AAA and methionine in CSF. These clinical observations were confirmed experimentally in rats treated with carbon tetrachloride (CCl4) and D-galactosamine by obtaining the elevation of neutral amino acid contents in the brain and the slight increase in the brain uptake index (BUI) of a radiolabeled amino acid.

Amino Acids↗
PubMed1983

Brain tyrosine hydroxylase activity and calculated amount of brain dopa synthesized in carbon tetrachloride-intoxicated rats.

Tyrosine hydroxylase activity in the corpus striatum was measured in a large dose of carbon tetrachloride (CC14)-intoxicated rats in order to confirm whether brain catecholamine contents decrease in acute hepatic failure or not. Theoretical amounts of dopa synthesized in the brain of the treated animals were calculated according to an equation of enzyme kinetics. Tyrosine hydroxylase activities in CCl4-injured rats were similar to those in control rats, and calculated amounts of brain dopa in liver-injured rats were rather higher as compared to those in untreated animals.

Amino Acids↗
PubMed1983

Effect of azathioprine and carbon tetrachloride on induction of hyperplastic liver nodule and hepatocellular carcinoma by diethylnitrosamine and N-2-fluorenylacetamide in rats.

The enhancing or inhibitory action of the hepatotoxic agents, carbon tetrachloride (CCl4) and azathioprine (AZP), on the evolution of hyperplastic liver nodule (HN) and hepatocellular carcinoma (HCC) in diethylnitrosamine (DEN)- and N-2-fluorenylacetamide (FAA)-treated rats (control group) was tested. The area of gamma-glutamyl transpeptidase(gamma-GTP)-positive HN and/or foci in the eighth week was remarkably small in rats fed on a diet containing FAA and AZP (the AZP group), but was quite large in rats fed a diet containing FAA in addition to repeated CCl4 injections (the CCl4 group). HCC was first detected in the 21st week and the incidence of HCC within the 36 weeks of the experiment was very high in the CCl4 group. However, no tumor, including HCC, was detected in the AZP group during this observation period. No essential differences in the biochemical characteristics of HCC between the control group and the CCl4 group were observed with respect to several enzyme activities. The increased activity of liver aniline hydroxylase observed 12 hr after the administration of FAA, AZP, or DEN decreased when AZP was administered simultaneously with FAA to rats treated with DEN in advance. The mechanisms of the enhancing of inhibitory effect observed are discussed with special reference to the drug-drug interactions.

2-Acetylaminofluorene↗
PubMed1983

Serum neutral amino acid concentrations in cirrhotic patients with impaired carbohydrate metabolism.

Serum neutral amino acid levels in cirrhotic patients with abnormal oral glucose tolerance test patterns were not different from those of subjects without impaired carbohydrate metabolism. However, the characteristic features of serum aminograms in the patients, that is, increased levels of tyrosine, decreased levels of valine and leucine and the diminished ratio of branched chain amino acids to phenylalanine and tyrosine levels, were less pronounced in those treated with insulin. This finding is clinically important for evaluating the serum aminogram of cirrhotic patients under insulin therapy.

Adult↗
PubMed1983

Effect of continued drinking on prognosis of alcoholic liver cirrhosis.

The prognoses of patients with alcoholic liver cirrhosis were compared between those who continued to drink and those who stopped. Clinical criteria were strictly set so as to control other variables affecting the prognoses. Four-year survival was significantly higher in the patients who stopped drinking than in those who continued to drink. Continued drinking worsens the prognosis of patients with alcoholic liver cirrhosis.

Adult↗
PubMed1983

A simple and rapid method for determining blood ammonia levels.

Blood ammonia levels in patients with various liver diseases were determined quantitatively by a simple and rapid method using the Amitest Meter System. The results were compared to those obtained by an enzymatic method and were well correlated. This simple Amitest is also useful in animal experiments, particularly when there is a need to determine blood ammonia levels serially. This paper test was evaluated as being accurate and reliable for clinical and experimental use.

Ammonia↗
PubMed1982

Characteristics change in serum amino acid levels in different types of hepatic encephalopathy.

Serum amino acid patterns in patients with different types of hepatic encephalopathy were investigated. Marked elevations in most of serum amino acids observed in untreated patients with acute type of fulminant hepatitis were not remarkable in the patients who have already treated; particularly branched chain amino acids (BCAA), phenylalanine and tyrosine were much lower in the latter group. However, elevation of serum methionine levels and lower ratio of BCAA/(phenylalanine + tyrosine) were similarly observed in both groups. In encephalopathic patients with decompensated cirrhosis, many amino acids such as phenylalanine, tyrosine and methionine were elevated with a slight depressed levels of serum BCAA. Highly significant decrease in serum BCAA levels and no elevation of phenylalanine and methionine with a minimal increase of tyrosine were observed in patients with chronic type of hepatic encephalopathy; other amino acids except for glutamine and arginine were much lower as compared to those in decompensated cirrhotics and even to the control values.

Adolescent↗
PubMed1982

Primary carcinoma of the gallbladder and the extrahepatic bile duct.

The clinical records of 68 patients with primary carcinoma of the gallbladder (39 cases) and the extrahepatic biliary tracts (29 cases) were comparatively reviewed. The survivals with carcinoma of the gallbladder were limited to five patients operated upon because of cholelithiasis and/or cholecystitis. The majority of the cases preoperatively diagnosed as cancer of the gallbladder were not able to undergo radical cholecystectomy. Of seven patients with radically resected tumors among 29 cases with carcinoma of the extrahepatic biliary tracts, only two patients survived and other five died with locally recurrent tumors. This experience reemphasizes the inadequacy of the present diagnosing approaches to the diseases. Therefore, for discovery of the early cases with primary carcinoma of the gallbladder and the extrahepatic biliary tracts, it may be far more important to make more aggressive measures by using newly developed diagnosing tools.

Adult↗
PubMed1982

Effects of intraduodenal feeding of a branched-chain amino acid-rich solution on ammonia-induced encephalopathy in liver-injured rats.

A preventive effect of intraduodenal prefeeding of a branched-chain amino acid (BCAA)-rich solution on ammonia-induced encephalopathy was investigated with carbon tetrachloride CC14-injured rats with the elevated levels of blood ammonia. Five out of six cirrhotic rats, to which an electrolyte solution alone was preinfused for 24 hours, fell into coma following ammonia acetate injection and two comatose rats died. However, no cirrhotic rats preinfused with a BCAA-rich solution died and only two out of the six showed coma with complete recovery. The similar preventive effect could not be observed in rats with acute liver injury.

Acetates↗