Publications by authors named "Yoshiki Komatsu"

Photodynamic therapy (PDT) is a noninvasive cancer treatment modality that involves the administration of photosensitizers and light irradiation. Previously, we established a polycation-containing hematoporphyrin (aHP) formulation that demonstrated superior antitumor efficacy , than the original hematoporphyrin (HP). In this study, we investigated underlining mechanisms of the high antitumor effect of aHP using cell experiments.

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Photodynamic therapy (PDT) is a great potential anti-tumor therapy owing to its non-invasiveness and high spatiotemporal selectivity. However, systemically administered photosensitizers diffuse in the skin and the eyes for a long duration, which cause phototoxicity to bright light and sunlight. Therefore, following PDT, patients must avoid exposure of to light and sunlight to avoid this phototoxicity.

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Recently, plasma membrane-targeted photodynamic therapy has attracted attention as an effective cancer immunotherapeutic strategy. However, the released photosensitizers do not only adhere to the plasma membrane but may also be internalized in the cytosol, in endosomes/lysosomes, hindering investigations of the effects of photosensitizers attached to the plasma membrane. In this study, we developed a cell culture dish with singlet oxygen-generating cell-adhesive glass surfaces that allows investigation of the effects of photosensitizers attached to the plasma membrane.

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Localization of tumors during laparoscopic surgery is generally performed by locally injecting India ink into the submucosal layer of the gastrointestinal tract using endoscopy. However, the location of the tumor is obscured because of the black-stained surgical field and the blurring caused by India ink. To solve this problem, in this study, we developed a tissue-adhesive porphyrin with polycations consisting of quaternary ammonium salt groups.

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Hyperthermia (HT) treatment is a noninvasive cancer therapy, often used with radiation therapy and chemotherapy. Compared with 37 °C, 42 °C is mild heat stress for cells and produces reactive oxygen species (ROS) from mitochondria. To involve subsequent intracellular accumulation of DOX, we have previously reported that the expression of ATP-binding cassette sub-family G member 2 (ABCG2), an exporter of doxorubicin (DOX), was suppressed by a larger amount of intracellular mitochondrial ROS.

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A 70-year-old woman was referred to our department due to a solitary mediastinal tumor which gradually grew near the site of anastomosis for 8 years after radical surgery of esophageal squamous cell carcinoma. It was difficult to distinguish the lymph node recurrence of esophageal cancer from another tumor of unknown primary origin. Endoscopic ultrasound-guided fine-needle aspiration was performed, and the tumor was diagnosed to be neuroendocrine carcinoma.

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A 69-year-old woman who had a history of chronic hepatitis C, autoimmune hemolytic anemia and myelodysplastic syndrome was treated with sorafenib at a daily dose of 400 mg for HCC with multiple lung metastases. Nonetheless, elevated serum tumor markers further increased (alpha fetoprotein from 121,100 to 348,660 ng/ml and protein induced by vitamin K absence/antagonist-II from 3435 to 29,357 mAU/ml), and lung metastatic lesions on chest X-ray showed no improvement after 2 months of sorafenib treatment. Sorafenib was discontinued because of adverse events with diarrhea, fatigue, and severe anemia due to bleeding from stomach telangiectasia.

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During analyses of the invasive Mediterranean mussel Mytilus galloprovincialis for pathologies in Tokyo Bay, infection by the protozoan parasite Perkinsus beihaiensis was found through histological examination, Ray's Fluid Thioglycollate Medium assays, and molecular analyses. Specific PCR assays for each Perkinsus species also revealed the presence of an indigenous congeneric species, Perkinsus olseni, but P. beihaiensis was dominant in M.

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