Publications by authors named "Takahiro Kohno"

We analyse a mathematical model of the population dynamics among a mimic, a corresponding model, and their common predator populations. Predator changes its search-and-attack probability by forming and losing its search image. It cannot distinguish the mimic from the model.

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The radial spoke (RS)/central pair (CP) system in cilia and flagella plays an essential role in the regulation of force generation by dynein, the motor protein that drives cilia/flagella movements. Mechanical and mechanochemicl interactions between the CP and the distal part of the RS, the spokehead, should be crucial for this control; however, the details of interaction are totally unknown. As an initial step toward an understanding of the RS-CP interaction, we examined the protein-protein interactions between the five spokehead proteins (radial spoke protein (RSP)1, RSP4, RSP6, RSP9, and RSP10) and three spoke stalk proteins (RSP2, RSP5, and RSP23), all expressed as recombinant proteins.

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Vascular endothelial growth factor (VEGF) is known to play a major role in angiogenesis in a variety of tumors. A soluble form of Flt-1 (sFlt-1), a VEGF receptor, is potentially useful as an antagonist of VEGF, and accumulating evidences suggest the applicability of sFlt-1 in tumor suppression by means of anti-angiogenesis. We previously demonstrated the efficacy of sflt-1 gene expression in situ to suppress tumor growth and ascites in ovarian cancer.

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The radial spoke is a ubiquitous component of '9+2' cilia and flagella, and plays an essential role in the control of dynein arm activity by relaying signals from the central pair of microtubules to the arms. The Chlamydomonas reinhardtii radial spoke contains at least 23 proteins, only 8 of which have been characterized at the molecular level. Here, we use mass spectrometry to identify 10 additional radial spoke proteins.

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SU6668 (TSU-68) is a small-molecule synthetic inhibitor of the angiogenic related receptor tyrosine kinases Flk-1/KDR, PDGFRbeta, and FGFR1. Using a mouse model of peritoneally disseminated ovarian cancer, we investigated whether SU6668 inhibits peritoneal dissemination and prolongs survival time. BALB/c nude mice were intraperitoneally (i.

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Problem: It has been shown that the presence of antinuclear antibody (ANA) might reduce pregnancy rates after in vitro fertilization-embryo transfer (IVF-ET). However, the mechanism of implantation failure by ANA has not yet been clarified. This study was performed to investigate the impact of ANA on pregnancy rates after IVF-ET, and the necessity of specific medication for infertile women who have ANA in their sera.

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Interleukin-10 (IL-10) is an immunosuppressive cytokine produced by T lymphocytes and drawing attention as an inhibitor of tumor angiogenesis. In this study, we investigated antiangiogenic and tumor suppressive effects of IL-10 in ovarian cancer cells. mIL-10-expressing plasmid was transferred into two ovarian cancer cell lines, SHIN-3 [vascular endothelial growth factor (VEGF) producing] and KOC-2S (non-VEGF producing).

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The prognosis of cancers of various organs overexpressing thymidylate synthase (TS) has been reported to be poor. It has been suggested that the poor prognosis is partly due to a low sensitivity of TS-overexpressing tumors to TS-targeting 5-fluorouracil (5-FU). To investigate the relationship between TS expression and sensitivity to 5-FU, we used the TS-overexpressing cervical cancer cell line SKG-II/TS and SKG-I/TS that had been established by TS gene transfer.

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The aim of this study was clarification of the feasibility, effects, and adverse events of combination chemotherapy with paclitaxel and carboplatin in Japanese women with epithelial ovarian cancer. In patients with stage Ic to IV epithelial ovarian cancer, primary cytoreductive surgery was performed. Paclitaxel (175 mg/m(2)) was intravenously infused for 3 h.

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Purpose: PTEN is a tumor suppressor gene that was identified on chromosome 10q23. In addition to its original function as a tumor suppressor, this gene product was recently reported to enhance the sensitivity of cancer cells to anticancer agents. It is for the purpose of this study to investigate its function and the mechanisms by which PTEN enhances the sensitivity of ovarian cancer to antitumor agents.

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Vascular endothelial growth factor (VEGF), a bifunctional protein enhancing vascular permeability and stimulating endothelial growth, is thought to be responsible for fluid accumulation and angiogenesis in ascites tumors. To investigate the effects of stable expression of the soluble form of Flt-1 VEGF receptor (sFlt-1), a known endogenous inhibitor of VEGF, on the malignant ascites tumors, we cotransduced RMG-1 human ovarian cancer cells with adeno-associated virus vectors carrying the sFlt-1 cDNA and Neo gene or Neo gene alone and isolated both the sFlt-1-expressing clone and the Neo-expressing clone. In vitro growth characteristics were essentially the same.

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We evaluated microsatellite instability (MSI) in primary lesions and lymph node metastatic lesions in 66 patients with endometrial carcinoma (FIGO stage IIIC) accompanied by lymph node metastasis. DNA was extracted from paraffin-embedded tissue of both the primary and lymph node metastatic lesions of endometrial carcinoma, and MSI was evaluated using microsatellite markers at five loci. Microsatellite instability was positive in the primary lesion in 27 patients (41%).

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