17 research outputs found

    Intraperitoneal administration of nanoparticles containing tocopheryl succinate prevents peritoneal dissemination

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    Intraperitoneal administration of anticancer nanoparticles is a rational strategy for preventing peritoneal dissemination of colon cancer due to the prolonged retention of nanoparticles in the abdominal cavity. However, instability of nanoparticles in body fluids causes inefficient retention, reducing its anticancer effects. We have previously developed anticancer nanoparticles containing tocopheryl succinate, which showed high in vivo stability and multifunctional anticancer effects. In the present study, we have demonstrated that peritoneal dissemination derived from colon cancer was prevented by intraperitoneal administration of tocopheryl succinate nanoparticles. The biodistribution of tocopheryl succinate nanoparticles was evaluated using inductively coupled plasma mass spectroscopy and imaging analysis in mice administered quantum dot encapsulated tocopheryl succinate nanoparticles. Intraperitoneal administration of tocopheryl succinate nanoparticles showed longer retention in the abdominal cavity than by its intravenous (i.v.) administration. Moreover, due to effective biodistribution, tumor growth was prevented by intraperitoneal administration of tocopheryl succinate nanoparticles. Furthermore, the anticancer effect was attributed to the inhibition of cancer cell proliferation and improvement of the intraperitoneal microenvironment, such as decrease in the levels of vascular endothelial growth factor A, interleukin 10, and M2-like phenotype of tumor-associated macrophages. Collectively, intraperitoneal administration of tocopheryl succinate nanoparticles is expected to have multifaceted antitumor effects against colon cancer with peritoneal dissemination

    Faint electric treatment-induced rapid and efficient delivery of extraneous hydrophilic molecules into the cytoplasm

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    Effective delivery of extraneous molecules into the cytoplasm of the target cells is important for several drug therapies. Previously, we showed effective in vivo transdermal delivery of naked siRNA into skin cells induced by faint electric treatment (ET) iontophoresis, and significant suppression of target mRNA levels (Kigasawa et al., Int. J. Pharm., 2010). This result indicates that electricity promoted the delivery of siRNA into cytoplasm. In the present study, we analyzed the intracellular delivery of naked anti-luciferase siRNA by faint ET, and found that the luciferase activity of cells expressing luciferase was reduced by in vitro ET like in vivo iontophoresis. Cellular uptake of fluorescent-label siRNA was increased by ET, while low temperature exposure, macropinocytosis inhibitor amiloride and caveolae-mediated endocytosis inhibitor filipin significantly prevented siRNA uptake. These results indicate that the cellular uptake mechanism involved endocytosis. In addition, voltage sensitive fluorescent dye DiBAC4 (3) penetration was increased by ET, and the transient receptor potential channel inhibitor SKF96365 reduced siRNA uptake, suggesting that faint ET reduced membrane potentials by changing intracellular ion levels. Moreover, to analyze cytoplasmic delivery, we used in-stem molecular beacon (ISMB), which fluoresces upon binding to target mRNA in the cytoplasm. Surprisingly, cytoplasmic ISMB fluorescence appeared rapidly and homogeneously after ET, indicating that cytoplasmic delivery is markedly enhanced by ET. In conclusion, we demonstrated for the first time that faint ET can enhance cellular uptake and cytoplasmic delivery of extraneous molecules

    Do present foraging success by adult themselves or by pairs affect foraging site selection

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    第6回極域科学シンポジウム[OB] 極域生物圏11月16日(月) 国立極地研究所1階交流アトリウ

    Development of method for evaluating cell hardness and correlation between bacterial spore hardness and durability

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    <p>Abstract</p> <p>Background</p> <p>Despite the availability of conventional devices for making single-cell manipulations, determining the hardness of a single cell remains difficult. Here, we consider the cell to be a linear elastic body and apply Young’s modulus (modulus of elasticity), which is defined as the ratio of the repulsive force (stress) in response to the applied strain. In this new method, a scanning probe microscope (SPM) is operated with a cantilever in the “contact-and-push” mode, and the cantilever is applied to the cell surface over a set distance (applied strain).</p> <p>Results</p> <p>We determined the hardness of the following bacterial cells: <it>Escherichia coli</it>, <it>Staphylococcus aureus</it>, <it>Pseudomonas aeruginosa</it>, and five <it>Bacillus</it> spp. In log phase, these strains had a similar Young’s modulus, but <it>Bacillus</it> spp. spores were significantly harder than the corresponding vegetative cells. There was a positive, linear correlation between the hardness of bacterial spores and heat or ultraviolet (UV) resistance.</p> <p>Conclusions</p> <p>Using this technique, the hardness of a single vegetative bacterial cell or spore could be determined based on Young’s modulus. As an application of this technique, we demonstrated that the hardness of individual bacterial spores was directly proportional to heat and UV resistance, which are the conventional measures of physical durability. This technique allows the rapid and direct determination of spore durability and provides a valuable and innovative method for the evaluation of physical properties in the field of microbiology.</p

    SCENARIO VIOLATION AS GAPS BETWEEN ACTIVITY PATTERNS

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    In this paper, we propose interactive and visual discovery method of hidden factors for accidents or incidents. Accidents or incidents tend to occur because of very small differences from an ideal situation. From the above viewpoint, we introduce scenario violation model and regard scenario violation as a gap from the proper scenario. Previously, we proposed abduction-based scenario violation determination strategy, but in this paper, we adopt the Kamishibai-KeyGraph to analyze multiple patterns at the same time. Then, we show a gap discovery procedure by using the Kamishibai-KeyGraph.Scenario violation, incident and accident, Kamishibai KeyGraph

    Tumor Microenvironment-Sensitive Liposomes Penetrate Tumor Tissue via Attenuated Interaction of the Extracellular Matrix and Tumor Cells and Accompanying Actin Depolymerization

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    Delivery of anticancer drugs into tumor cores comprised of malignant cancer cells can result in potent therapeutic effects. However, conventional nanoparticle-based drug delivery systems used for cancer therapy often exhibit inefficient tumor-penetrating properties, thus, suggesting the need to improve the functional design of such systems. Herein, we focus on the interactions between cancer cells and the extracellular matrix (ECM) and demonstrate that liposomes modified with slightly acidic pH-sensitive peptide (SAPSp-lipo) can penetrate in vivo tumor tissue and in vitro spheroids comprised of cancer cells and ECM. We previously reported SAPSp-lipo, tumor microenvironment-sensitive liposomes, are effectively delivered to tumor tissue (Hama et al. <i>J Control Release</i> <b>2015</b>, <i>206</i>, 67–74). Compared with conventional liposomes, SAPSp-lipo could be delivered to deeper regions within both spheroids and tumor tissues. Furthermore, tumor penetration was found to be promoted at regions where actin depolymerization was induced by SAPSp-lipo and inhibited by the polymerization of actin. In addition, SAPSp-lipo attenuated the interaction between cancer cells and ECM, contributing to the penetration of SAPSp-lipo. These results suggest that SAPSp-lipo penetrates tumors via the interspace route and is accompanied by actin depolymerization. Taken together, SAPSp-lipo demonstrates potential as a novel tumor-penetrable drug carrier for induction of therapeutic effects against malignant cells that comprise tumor cores

    Multicenter, Open Label, Randomized Controlled Superiority Trial for Availability to Reduce Nocturnal Urination Frequency: Study Protocol for a TOP-STAR Study

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    Nocturia is a common disease in patients with type 2 diabetes mellitus that can reduce the quality of life. Sodium glucose co-transporter 2 (SGLT2) inhibitors increase the urine volume and are often discontinued when polyuria occurs, although tofogliflozin, which has a short half-life in the blood, may improve nocturia by managing hyperglycemia and hypertension, without aggravating nocturia. As excessive sodium intake worsens nocturia and increases urine volume, sodium restriction is also effective in managing nocturia. This multicenter, open-label, randomized parallel-group trial will examine 80 patients with type 2 diabetes who experienced nocturia. After the baseline examination, the patients are randomly stratified into two groups and receive tofogliflozin treatment with or without sodium restriction for 12 weeks. The primary outcome is nocturia frequency at 12 weeks. The secondary outcomes are the frequency of daytime urine, changes in urine volume, and changes in home blood pressure
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