Biomedical subjects

Y Nadaoka

Publications and source records attributed to Y Nadaoka.

5 recordsLinked to original sources

PubMed2000

Malignant transformation and EGFR activation of immortalized mouse liver epithelial cells caused by HBV enhancer-X from a human hepatocellular carcinoma.

We have previously observed that all human hepatocellular carcinomas (HCCs) from HBV carriers examined had the integrated X region. In this study, HBV DNA was isolated from an integration site in one HCC that had a single, very small integrated viral DNA including the X region, but it had no expression of X gene as poly(A)RNA. It was found that HBV DNA was present between alphoid repetitive sequences, and it included Enhancer and X regions, encompassing the adr sequence from 910 to 1811. Nucleotides for 8 amino acids at the 3' end, a stop codon of X gene and a poly(A) signal downstream of X gene were lost by integration, and nucleotides for 7 amino acids and a stop codon were substituted by a connected alphoid sequence. When this cloned HBV DNA was transfected with an expression vector to an immortalized mouse liver epithelial cell line, MLE-10, malignant transformation occurred. Transformants having expressed poly(A)RNA of the X gene showed anchorage-independent growth in soft agar and tumor formation in the subcutis of nude mice. The mRNA level of EGFR was found to be remarkably enhanced in X-transformed cells, in contrast with the absence of this mRNA in parental and ras-transformed MLE-10. Our data provide evidence that the Enhancer-X region alone is the key contributor to the malignant change of pre-malignant liver cells in HBV carriers through activation of some specific genes, such as EGFR.

Amino Acid Sequence↗

PubMed1998

A database for cell signaling networks.

We developed a data and knowledge base for cellular signal transduction in human cells, to make this rapidly growing information available. The database includes all the biological properties of cellular signal transduction, including biological reactions that transfer cellular signals and molecular attributes characterized by sequences, structures, and functions. Since the database is based on the object-oriented technique, highly flexible methods of data definition and modification are necessary to handle this diverse and complex biological information. The database includes attractive graphical representations of signaling cascades and the three-dimensional structure of molecules. The database is a novel application of ACEDB, which was the database originally developed to store the C. elegans genome. The database can be accessed through the Internet at http://geo.nihs.go.jp/csndb.html.

Cells↗

PubMed1996

Reduction of the allergenicity of soybean by treatment with proteases.

Soybeans were treated with proteases to reduce allergenicity. By immunoblotting with a monoclonal antibody against a major soybean allergen (Gly m Bd 30K), two of eight proteases so far tested were selected to achieve a reduction in allergenicity. Both antigenicity to the monoclonal antibody and allergenicity to the sera from soybean-sensitive patients proved to be markedly reduced by processing with either protease. Thus, soybeans treated with an appropriate protease may possibly be supplied as a hypoallergenic foodstuff for patients.

Adult↗

PubMed1995

A novel missense mutation (C522Y) is present in the beta-hexosaminidase beta-subunit gene of a Japanese patient with infantile Sandhoff disease.

A novel missense mutation (1565G-->A) was identified in the cDNA and genomic DNA coding for the beta-hexosaminidase beta-subunit of a Japanese patient with infantile Sandhoff disease. The patient was homozygous for this mutation, which should result in a cysteine-to-tyrosine substitution at codon 522. Computer-assisted analysis of this amino acid substitution predicted alteration in the secondary structure in the region of a highly conserved sequence. An immunofluorescence study revealed the accumulation of GM2 ganglioside in cultured fibroblasts from the patient with this mutation.

Base Sequence↗

PubMed1990

Partial deletion of human alpha-galactosidase A gene in Fabry disease: direct repeat sequences as a possible cause of slipped mispairing.

A partial deletion involving exon 3 associated with a single base change (A to C) was found in the alpha-galactosidase A gene of a hemizygous male Fabry patient and his mother, a heterozygous proband. This 402-bp deletion was flanked by 6-bp direct repeat sequences, and the intervening portion was found to have unique complementary sequences. These specific structures may have promoted "slipped mispairing" in this family.

Base Sequence↗