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Biomedical subjects

C Takeuchi

Publications and source records attributed to C Takeuchi.

9 recordsLinked to original sources
PubMed1998

New taxanes as highly efficient reversal agents for multidrug resistance in cancer cells.

New non-cytotoxic taxanes synthesized from 10-deacetylbaccatin III and special hydrophobic acylating agents show remarkable MDR reversal activity (< or = 99.8%) against drug-resistant human breast cancer cells when co-administered with paclitaxel or doxorubicin. This activity is ascribed to the highly efficient blocking of P-glycoprotein efflux by these new taxanes.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1996

Sequence analysis of the genome of the unicellular cyanobacterium Synechocystis sp. strain PCC6803. II. Sequence determination of the entire genome and assignment of potential protein-coding regions.

The sequence determination of the entire genome of the Synechocystis sp. strain PCC6803 was completed. The total length of the genome finally confirmed was 3,573,470 bp, including the previously reported sequence of 1,003,450 bp from map position 64% to 92% of the genome. The entire sequence was assembled from the sequences of the physical map-based contigs of cosmid clones and of lambda clones and long PCR products which were used for gap-filling. The accuracy of the sequence was guaranteed by analysis of both strands of DNA through the entire genome. The authenticity of the assembled sequence was supported by restriction analysis of long PCR products, which were directly amplified from the genomic DNA using the assembled sequence data. To predict the potential protein-coding regions, analysis of open reading frames (ORFs), analysis by the GeneMark program and similarity search to databases were performed. As a result, a total of 3,168 potential protein genes were assigned on the genome, in which 145 (4.6%) were identical to reported genes and 1,257 (39.6%) and 340 (10.8%) showed similarity to reported and hypothetical genes, respectively. The remaining 1,426 (45.0%) had no apparent similarity to any genes in databases. Among the potential protein genes assigned, 128 were related to the genes participating in photosynthetic reactions. The sum of the sequences coding for potential protein genes occupies 87% of the genome length. By adding rRNA and tRNA genes, therefore, the genome has a very compact arrangement of protein- and RNA-coding regions. A notable feature on the gene organization of the genome was that 99 ORFs, which showed similarity to transposase genes and could be classified into 6 groups, were found spread all over the genome, and at least 26 of them appeared to remain intact. The result implies that rearrangement of the genome occurred frequently during and after establishment of this species.

Bacterial Proteins↗
PubMed1990

Type-C virus-like particles in a human B-cell lymphoma cell line.

Type-C virus-like particles (VLPs) were found in an Epstein-Barr (EB) virus-infected human B-cell lymphoma cell line, SP-50B, that was established from a patient with non-Hodgkin lymphoma. The cell line continuously produces a small number of type-C VLPs, 150-200 nm in diameter, over 1 year. SP-50B cells were negative for HTLV-I and HTLV-II antigens and did not contain the HTLV-I genome. In addition, two EB virus nuclear antigen (EBNA)-positive B-cell lines, SP-54-Cord and SP-57-CLL, were established from human cord blood and chronic lymphocytic leukemia (CLL), respectively, by coculture with lethally irradiated SP-50B cells. Type-C VLPs with the same morphology were also found in both cell lines.

Antibodies, Antinuclear↗