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H Ariga

Publications and source records attributed to H Ariga.

At least 145 records · Page 8Linked to original sources
PubMed1985

Determination and significance of a new carbohydrate antigen CA19-9 in digestive system cancers.

To assess the diagnostic significance of CA19-9, the serum levels in 225 healthy subjects, 201 patients with cancers, 423 patients with benign diseases and 21 pregnant women, were determined by RIA. The mean CA19-9 level of the healthy subjects was 11.2 +/- 0.4 U/ml (range, 6-100 U/ml). Only 3.1% of them were above 37 U/ml. The CA19-9 levels were elevated above 37 U/ml in 7.9% of 293 patients with non-carcinomatous diseases of the digestive system. Among digestive system cancers, elevated levels were found in 18.2% of 11 patients with esophageal cancer, 42.7% of 68 patients with gastric cancer, 39.1% of 23 patients with colorectal cancer, 27.8% of 18 patients with primary hepatic cancer, 71.4% of 35 patients with biliary cancer, and 75% of 20 patients with pancreatic cancer. Most of the patients with levels above 100 U/ml had carcinomatous diseases. The CA19-9 positive rates for patients with gastric cancer and colorectal cancer were extremely low at stages I, II and III, while in patients at stage IV and in patients with recurrent cancer, a tendency for rapid increase in the positive rates and concentrations of CA19-9 was noted. Based on combination assay of CA19-9, CEA and ferritin, in comparison with the positive rates for CA19-9 alone, it was found that the rates were raised to 42.7% in gastric cancer, to 39.1% in colorectal cancer, and to 71.4% in biliary cancer, suggesting the simultaneous determination with these tumor markers may serve to elevate their usefulness.

Adolescent↗
PubMed1984

Identification of the replicative intermediates in SV40 DNA replication in vitro.

The soluble replication system is which the exogenously added simian virus 40 (SV40) DNA can be replicated semiconservatively in vitro, has been developed (Ariga and Sugano, J.Virol. 48, 481, 1983). This paper further characterized the in vitro products synthesized on the cloned DNA containing the origin of SV40 DNA replication. The time course and pluse-chase experiments showed that the in vitro products were converted from the open circle to closed circles having the various superhelical densities, and finally to the twisted formI DNA seen in vivo by the analysis of agarose gel electrophoresis, alkaline sucrose gradient centrifugation, and density-transfer in isopycnic centrifugation. The replicative intermediates isolated after the short term incubation had replicated strands of the size smaller than the full length, most of which correspond to that of the putative Okazaki fragment. These and the previous results indicate that this in vitro system should be useful to investigate the molecular mechanism of SV40 DNA replication.

DNA Replication↗
PubMed1984

Adenovirus DNA synthesized in the presence of aphidicolin.

Adenovirus types 2 and 5 DNA synthesized in vivo and in vitro in the presence of aphidicolin were studied. Inhibition of adenoviral DNA synthesis by aphidicolin was only 70% even at a concentration of 30 micrograms/ml of aphidicolin, at which the cellular DNA synthesis was completely inhibited. When initiation of the viral DNA synthesis was synchronized with hydroxyurea and labeled with [3H]thymidine for 60 min, the viral DNA synthesized in the presence of 30 micrograms/ml of aphidicolin was not of full length (35 kb) but small (approximately 12 kb) by analysis of alkaline sucrose density gradient centrifugation. When initiation of the viral DNA synthesis was not synchronized, the viral DNAs ranging from full size to 12 kb were synthesized in the presence of aphidicolin, indicating that the nascent DNAs longer than about 12 kb can continue to elongate in the presence of aphidicolin. This 12 kb DNA was not derived from the degradation products of newly synthesized full size adenoviral DNA. The viral DNA synthesis was restored and the full size of adenoviral DNA was attained within 15 min following removal of aphidicolin. About 20% of the entire viral genome length from the 5'-end was not inhibited by aphidicolin, while the synthesis of interior fragments of the adenoviral DNA was markedly inhibited by aphidicolin, judging from the electrophoretic pattern on neutral agarose gel after digestion of DNA with Hind III. These results indicate that aphidicolin inhibits adenoviral DNA replication at the internal region located approximately 20-30% from both terminals.

Adenoviruses, Human↗
PubMed1984

Expression of a cloned gene segment of poliovirus in E. coli: evidence for autocatalytic production of the viral proteinase.

The poliovirus polyprotein is proteolytically processed predominantly by a virus-encoded proteinase (P3-7c) that cleaves glutamine-glycine amino acid pairs. The biosynthesis of the viral proteinase, itself a product of glutamine-glycine cleavages, was studied by constructing a bacterial expression plasmid that contained a cloned segment of the poliovirus genome slightly larger than the coding region for P3-7c. The induction of expression of this plasmid in E. coli produced several poliovirus-specific polypeptides. One polypeptide, an unstable protein called 3i, was the product of fortuitous in-phase initiation of translation within the coding region of P3-7c. Three other induced polypeptides were products of proteolytic cleavages, the smallest (polypeptide 3) having the properties (amino-terminal amino acids, carboxy-terminal amino acids, size, antigenicity) of P3-7c. Insertion of a DNA linker into the P3-7c coding region results in the loss of P3-7c-specific glutamine-glycine cleavage activity. We conclude that P3-7c was produced by autocatalytic cleavage.

Amino Acid Sequence↗
PubMed1984

Replication of cloned DNA containing the Alu family sequence during cell extract-promoting simian virus 40 DNA synthesis.

The replicating activity of several cloned DNAs containing putative origin sequences was examined in a cell-free extract that absolutely depends on simian virus 40 (SV40) T antigen promoting initiation of SV40 DNA replication in vitro. Of the three DNAs containing the human Alu family sequence (BLUR8), the origin of (Saccharomyces cerevisiae plasmid 2 micron DNA (pJD29), and the yeast autonomous replicating sequence (YRp7), only BLUR8 was active as a template. Replication in a reaction mixture with BLUR8 as a template was semiconservative and not primed by a putative RNA polymerase III transcript synthesized on the Alu family sequence in vitro. Pulse-chase experiments showed that the small-sized DNA produced in a short-term incubation was converted to full-length closed circular and open circular DNAs in alkaline sucrose gradients. DNA synthesis in extracts began in a region of the Alu family sequence and was inhibited 80% by the addition of anti-T serum. Furthermore, partially purified T antigen bound the Alu family sequence in BLUR8 by the DNA-binding immunoassay. These results suggest that SV40 T antigen recognizes the Alu family sequence, similar to the origin sequence of SV40 DNA, and initiates semiconservative DNA replication in vitro.

Animals↗
PubMed1984

[Serum determination of CA 19-9 in patients with digestive cancers and its diagnostic evaluation].

The precision of CA 19-9 RIA kit was evaluated by recovery, reproducibility and dilution test with very satisfactory results. The CA 19-9 value in sera from 52 healthy individuals and from 224 patients with gastric intestinal cancer and other benign disease, showed an increased positive rate in several cases of gastric intestinal cancer. For example, the positive rate in pancreatic cancer, bile duct cancer, colo-rectal cancer, gastric cancer, esophagus cancer, primary biliary cirrhosis diabetes mellitus, liver cirrhosis and chronic hepatitis was 60%, 75%, 55.6%, 45.6%, 20%, 28.6%, 22.7%, 13.7% and 1.7% respectively. By contrast, values from patients with acute hepatitis, fulminant hepatitis, fatty liver, gastric duodenal ulcer, pancreatitis, and primary liver cancer were within the normal range. In this study, CA 19-9 RIA were found to be significant as an adjunct in the management of patients with gastrointestinal cancer, especially pancreatic cancer, and bile duct cancer.

Antigens, Neoplasm↗
PubMed1983

Effect of aphidicolin on the elongation step of adenovirus DNA replication in vitro.

Adenovirus DNA synthesis carried out in vitro was inhibited by the aphidicolin. However, 30% of the DNA synthesis was resistant to aphidicolin even at a concentration of 200 micrograms/ml. When the distribution patterns of the radioactivity of the products synthesized in the presence of 50 micrograms/ml of the drug was examined after HindIII digestion of the product DNA, the radioactivity appeared preferentially in the fragments mapping nearest to the ends of the molecule. Pulse-chase experiment showed that the terminal fragments were synthesized with or without aphidicolin but that in the presence of aphidicolin the rate of elongation rapidly slowed down beyond this region, suggesting that a DNA polymerase sensitive to aphidicolin may participate in the synthesis of the internal region of adenovirus DNA.

Adenoviridae↗
PubMed1983

Initiation of simian virus 40 DNA replication in vitro.

Exogenously added simian virus 40 (SV40) DNA can be replicated semiconservatively in vitro by a mixture of a soluble extract of HeLa cell nuclei and the cytoplasm from SV40-infected CosI cells. When cloned DNA was used as a template, the clone containing the SV40 origin of DNA replication was active, but a clone lacking the SV40 origin was inactive. The major products of the in vitro reaction were form I and form II SV40 DNAs and a small amount of form III. DNA synthesis in extracts began at or near the in vivo origin of SV40 DNA synthesis and proceeded bidirectionally. The reaction was inhibited by the addition of anti-large T hamster serum, aphidicolin, or RNase but not by ddNTP. Furthermore, this system was partially reconstituted between HeLa nuclear extract and the semipurified SV40 T antigen instead of the CosI cytoplasm. It is clear from these two systems that the proteins containing SV40 T antigen change the nonspecific repair reaction performed by HeLa nuclear extract alone to the specific semiconservative DNA replication reaction. These results show that these in vitro systems closely resemble SV40 DNA replication in vivo and provide an assay that should be useful for the purification and subsequent characterization of viral and cellular proteins involved in DNA replication.

Antigens, Viral, Tumor↗
PubMed1981

Multiple rounds of adenovirus DNA synthesis in vitro.

Adenovirus (Ad) type 2 DNA synthesis can be initiated in the presence of a soluble extract of uninfected HeLa cell nuclei, a 25-60% saturated ammonium sulfate fraction of infected cytoplasm and viral DNA covalently linked to a 5'-terminal protein (Ad DNA-prot). As the purification, from either the nuclei or cytoplasm, of factors active in DNA replication proceeded, various nonreplicative reactions which incorporate labeled deoxynucleotides were uncovered. In order to distinguish replicative from repair reactions, an assay was developed in which the Ad DNA-prot was digested with Xba I, all of the fragments so produced were used (without separation) in a replication reaction, and the products were assayed by electrophoresis on neutral agarose gels. In replicative reactions, most of the radioactivity was incorporated into the terminal fragments, with the internal fragments remaining unlabeled. Infected cytoplasm contains a "discrimination" function in addition to specific factors for Ad DNA replication. The discrimination factors inhibit the nonspecific nucleotide incorporation by uninfected HeLa nuclear extracts on Ad DNA-prot. The specific replicative incorporation into the terminal Ad DNA-prot fragments has also allowed an independent assay for reinitiation of progeny molecules synthesized in vitro. After the first round of replication, the 5' strand of the progeny duplex from each end is labeled. These same labeled strands will be displaced during the second round of replication and appear in new bands which have been shown to be the single-strand equivalents of the terminal fragments. Thus, at least two rounds of Ad DNA synthesis can initiate at each terminus in vitro. The appearance of displaced single strands requires DNA replication because the addition of dideoxycytidine triphosphate after the first round of synthesis prevents the displacement reaction. Both the progeny single- and double-stranded DNA appear to be linked to protein.

Adenoviruses, Human↗
PubMed1980

A 6-year-old boy having hepatocellular carcinoma associated with hepatitis B surface antigenemia.

Hepatocellular carcinoma associated with hepatitis B virus (HBV) infection occurring in a boy who was 6 years 2 months old is reported. The patient is thought to have been infected with HBV by exchange blood transfusion (horizontal infection) in the neonatal period. Jaundice appeared eight months after birth. He was subsequently treated and follow-up with a diagnosis of hepatitis B surface (HBs) antigen (Ag)-positive chronic persistent hepatitis. His mother and other family members were HBsAg-negative. Postmortem examination revealed a multinodular growth of hepatocellular carcinoma of trabecular and solid pattern, mainly of the right lobe, complicated with mild fibrosis of the liver. Numerous HBsAg-positive hepatocytes demonstrated by orcein staining and the indirect immunoperoxidase method were present in the noncancerous area. This hepatocellular carcinoma is considered to have occurred within six years two months after HBV infection and not to have been associated with liver cirrhosis. The present case may be valuable for assessing the oncogenic properties of HBV and the incubation period of HBV infection before it develops into hepatocellular carcinoma.

Carcinoma, Hepatocellular↗
PubMed1979

Complementation of the temperature-sensitive defect in H5ts125 adenovirus DNA replication in vitro.

Soluble extracts of adenovirus-infected HeLa cell nuclei support DNA replication on exogenous adenovirus DNA templates. Conditions of synthesis using both wild-type and temperature-sensitive extracts have been defined. Nuclear extracts prepared from cells permissively infected with the adenovirus mutant H5ts125 expressed the temperature-sensitive phenotype and could be inactivated at 37 degrees C in vitro. These extracts were completely complemented by the addition of wild-type adenovirus DNA binding protein but not by H5ts125 DNA binding protein. Enhancement by binding protein in the mutant extracts represents replication, as demonstrated by the production of full-sized products and orderly chain elongation originating, as in vivo, at both ends of the linear DNA. Replicative synthesis required the 5'-terminal protein bound covalently to template DNA and could be inhibited by denaturation of this 55,000-dalton protein. Various inhibitors of eukaryotic DNA polymerases, such as aphidicolin and 2',3'-dideoxythymidine triphosphate, inhibited replication of exogenous adenovirus templates in this system as they do in previously reported systems that only elongate endogenous replicating intermediates.

Adenoviruses, Human↗