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7. Cell-Penetrating Peptide-Mediated Biomolecule Transportation in Artificial Lipid Vesicles and Living Cells.

Author

Miwa, Akari and Kamiya, Koki

Subjects
*CELL-penetrating peptides, *MEMBRANE proteins, *NUCLEIC acids, *CELL physiology, *PEPTIDES
Abstract

Signal transduction and homeostasis are regulated by complex protein interactions in the intracellular environment. Therefore, the transportation of impermeable macromolecules (nucleic acids, proteins, and drugs) that control protein interactions is essential for modulating cell functions and therapeutic applications. However, macromolecule transportation across the cell membrane is not easy because the cell membrane separates the intra/extracellular environments, and the types of molecular transportation are regulated by membrane proteins. Cell-penetrating peptides (CPPs) are expected to be carriers for molecular transport. CPPs can transport macromolecules into cells through endocytosis and direct translocation. The transport mechanism remains largely unclear owing to several possibilities. In this review, we describe the methods for investigating CPP conformation, translocation, and cargo transportation using artificial membranes. We also investigated biomolecular transport across living cell membranes via CPPs. Subsequently, we show not only the biochemical applications but also the synthetic biological applications of CPPs. Finally, recent progress in biomolecule and nanoparticle transportation via CPPs into specific tissues is described from the viewpoint of drug delivery. This review provides the opportunity to discuss the mechanism of biomolecule transportation through these two platforms. [ABSTRACT FROM AUTHOR]

Published
2024
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12. Measurements of Transit Timing Variations for WASP-5b

Author

Fukui, Akihiko, Narita, Norio, Tristram, Paul J., Sumi, Takahiro, Abe, Fumio, Itow, Yoshitaka, Sullivan, Denis J., Bond, Ian A., Hirano, Teruyuki, Tamura, Motohide, Bennett, David P., Furusawa, Kei, Hayashi, Fumiya, Hearnshaw, John B., Hosaka, Shun, Kamiya, Koki, Kobara, Shuhei, Korpela, Aarno, Kilmartin, Pam M., Lin, Wei, Ling, Cho Hong, Makita, Shota, Masuda, Kimiaki, Matsubara, Yutaka, Miyake, Noriyuki, Muraki, Yasushi, Nagaya, Maiko, Nishimoto, Kenta, Ohnishi, Kouji, Omori, Kengo, Perrott, Yvette, Rattenbury, Nicholas, Saito, Toshiharu, Skuljan, Ljiljana, Suzuki, Daisuke, Sweatman, Winston L., and Wada, Kohei

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We have observed 7 new transits of the `hot Jupiter' WASP-5b using a 61 cm telescope located in New Zealand, in order to search for transit timing variations (TTVs) which can be induced by additional bodies existing in the system. When combined with other available photometric and radial velocity (RV) data, we find that its transit timings do not match a linear ephemeris; the best fit \chi^2 values is 32.2 with 9 degrees of freedom which corresponds to a confidence level of 99.982 % or 3.7 \sigma. This result indicates that excess variations of transit timings has been observed, due either to unknown systematic effects or possibly to real TTVs. The TTV amplitude is as large as 50 s, and if this is real, it cannot be explained by other effects than that due to an additional body or bodies. From the RV data, we put an upper limit on the RV amplitude caused by the possible secondary body (planet) as 21 m s^{-1}, which corresponds to its mass of 22-70 M_{Earth} over the orbital period ratio of the two planets from 0.2 to 5.0. From the TTVs data, using the numerical simulations, we place more stringent limits down to 2 M_{Earth} near 1:2 and 2:1 mean motion resonances (MMRs) with WASP-5b at the 3 \sigma level, assuming that the two planets are co-planer. We also put an upper limit on excess of Trojan mass as 43 M_{Earth} (3 \sigma) using both RV and photometric data. We also find that if the possible secondary planet has non- or a small eccentricity, its orbit would likely be near low-order MMRs. Further follow-up photometric and spectroscopic observations will be required to confirm the reality of the TTV signal, and results such as these will provide important information for the migration mechanisms of planetary systems., Comment: accepted for publication in PASJ, 30 pages, 8 figures, 8 tables

Published
2010
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22. Expression of HMGB1 in Organs in a Rodent Model of Transient Ischemia

Author

Kajiwara, Ryo, primary, Otaki, Ryo, additional, Inahara, Yuya, additional, Kamiya, Koki, additional, Negishi, Hiroshi, additional, Kobayashi, Masato, additional, Kumagawa, Takahiro, additional, Igarashi, Takahiro, additional, Shijo, Katsunori, additional, Moro, Nobuhiro, additional, Oshima, Hideki, additional, Maeda, Takeshi, additional, Asano, Masatake, additional, and Yoshino, Atsuo, additional

Published
2022
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24. 次世代型宇宙用デブリモニタBBMの開発

Author

MATSUZAKI, Noriko, MATSUMOTO, Haruhisa, NAKANISHI, Daiki, NAGAMATSU, Aiko, and KAMIYA, Koki

Abstract

第9回スペースデブリワークショップ (2021年2月24-26日. 宇宙航空研究開発機構調布航空宇宙センター(JAXA)(CAC), オンライン会議), 調布市, 東京, The 9th Space Debris Workshop (February 24-26, 2021. Chofu Aerospace Center, Japan Aerospace Exploration Agency (JAXA)(CAC), Online meeting), Chofu, Tokyo, Japan, 宇宙デブリセンサSDM は、JAXA 研究開発部門で開発を行っている軌道上直接観測用のデブリセンサである。ターゲットである高度600-1000km 上のサブミリサイズのデブリは、大きいものに比べて圧倒的に数が多く、今後も急増することが予測されている。その一方で、十分なデータが取得できておらず、データ取得は世界的に急務の課題となっている。このSDM の特徴は、シンプルな機構を持ち、特別な校正が必要ないという点である。この利点を活かして他のセンサーと組み合わせて利用することも可能であり、現在NASA ODPO と協力の下、軌道上運用を目的としたデブリセンサの開発を行っている。SDM は検出エリアと回路部からなっており、検出エリアは極薄のポリイミドフィルム上に、数千本の50 μm 幅の導線を細線加工したものである。ここにデブリが衝突することにより、100 μm~数mm のデブリの直径が取得できる。本講演では、BBM の開発状況と今後の計画を紹介する。, The space debris monitor (SDM) is a flight experienced in-situ debris sensor focusing on micro to mill sized debris on 600 - 1000 km orbit. A continuous in-situ observation of those small debris at 600 to 1000 km has never been conducted. However, this information is essential to properly understand the current situation of vast amount of small debris orbiting near our earth because they are becoming a dominant risk factor on orbit. The unique point of the SDM is its simple detection system which does not need any special calibrations. Thanks to this advantage, the SDM has the potential to collaborate easily with other debris sensors. The SDM consists of a debris-detection area and circuit areas. The debris-detection area is made of very thin polyimide film and there are thousands of 50 μm-wide conductive grid lines capable of detecting the diameter of collided debris sized from 100 μm to millimeters. On this presentation, the current status of developing the SDM BBM and our future plan will be shared with audiences., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA2130003026, レポート番号: JAXA-SP-21-001

Published
2021

36. 高エネルギー中性子・ガンマ線からみた太陽粒子加速についての一考察

Author

Muraki, Yasushi, Kamiya, Koki, Koga, Kiyokazu, Matsumoto, Haruhisa, Masuda, Satoshi, and Shibata, Shoichi

Abstract

第15回宇宙環境シンポジウム (2018年10月30日-31日. 東北大学青葉サイエンスホール), 仙台市, 宮城県, 2017年9月4日から9月10日にかけて、太陽活動極小期では珍しい大きなフレアが太陽表面で数回発生した。これらのフレアのなかでも9月6日と9月10日に発生したフレアでは高エネルギーガンマ線と中性子の両者が観測された。本講演では観測された高エネルギー粒子発生機構について考察した結果を発表した。これはそのレジュメである。GOES衛星の観測によると、9月6日と9月10日のフレア強度は、それぞれX2.2とX9.3（9月6日）、及びX8.2（9月10日）であった。, 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA1830019004, レポート番号: JAXA-SP-18-009

Published
2019

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