Tezukayama University

The study of coordination and cooperation games constitutes a central area of behavioral economics, addressing how individuals achieve mutually beneficial outcomes despite conflicts between individual and collective interests. Coordination and cooperation problems arise in a wide range of contexts, including charitable giving, volunteering, proenvironmental behavior, and helping behavior in social and economic interactions.

We investigated the development of composite materials endowed with antimicrobial properties with a view using natural materials to reduce the amount of plastic in use. In this study, we focused on bamboo powder, which has long been known as a natural material endowed with antimicrobial properties. We tested the antimicrobial properties of heat-treated bamboo powder to obtain its antimicrobial spectrum. Next, we estimated the antimicrobial properties of high-density polyethylene (HDPE) with 50 wt％ heat-treated bamboo powder composites. As a result, we clarified the antimicrobial properties in respect to Staphylococcus aureus in bamboo powder by heating at appropriate temperatures. We also confirmed the antimicrobial properties of bamboo powder in respect to Bacillus subtilis, Moraxella osloensis, and Escherichia coli. Furthermore, we found that the bamboo powder/HDPE composite could be endowed with antimicrobial properties without heating the bamboo powder in advance by increasing temperature in the molding processing. These results imply that the antimicrobial properties of bamboo powder/HDPE composite can be controlled by selecting the processing temperature.

For quadratic curves over finite fileds, the number of solutions, which is governed by an analogue of the Mordell-Weil group, is expressed with the Legendre symbol of a coefficient of quadratic curves. Focusing on the number of solutions, a quadratic curve analogue of the modular form in the Taniyama-Shimura conjecture is proposed. This modular form yields the Gaussian sum and also possesses some modular transformation structure.

We discuss on the problem of the electromagnetic radiation from the accelerated charged particle and the back reaction of that. The free-falling charged particle radiates the electromagnetic wave. The charged particle on the surface of the earth does not radiate the electromagnetic wave. The existence or the non-existence of the electromagnetic radiation from the charged particle and the back reaction of that is independent of the observer, which is consistent with the energy conservation. A paradox comes from combining this phenomenon with the equivalence principle in the theory of the general relativity. We consider the Hawking effect in the context of this paradox. We give our resolution on this paradox.

Abstract Background The optimal choice of drug is important in treating metastatic breast cancer, and the efficacy of the drug should be determined early, especially in cases of progression. On the other hand, untreated de novo Stage IV (dnST-IV) patients are expected to be more sensitive to drugs, but no detailed data are available. In JCOG1017 (Randomized trial of primary tumor resection in dnST-IV), dnST-IV patients were treated with primary systemic therapy for 3 months according to breast cancer subtypes before randomization. We already presented the results of primary endpoint. Primary tumor resection (PTR) could not significantly prolong the overall survival of de-novo stage IV breast cancer patients with sensitivity to primary systemic therapy. We conducted the supplementary analysis of JCOG1017 to clarify the efficacy of primary systemic therapy for dnST-IV and develop optimal treatment strategies for dnST-IV breast cancer. Methods In JCOG1017, systemic therapy was performed for each subtype/metastatic status as follows; 1) hormone therapy: ER+ HER2- and no life-threatening metastases, 2) weekly PTX therapy: life-threatening metastases, or ER-HER2-, 3) trastuzumab + pertuzumab + docetaxel (HPD) therapy OR trastuzumab + paclitaxel (HPTX) therapy: ER-HER2+. 4) hormone therapy: ER+HER2+ and no life-threatening metastases. The non-PD rate (no increase of more than 10% of the sum of the diameters of the target lesions compared before systemic therapy), the responses rate (cCR or cPR), and overall survival (OS) of responder (cCR or cPR)/non-responder (cSD or cPD) and PD/non-PD were examined. Results Among 569 patients who received primary systemic therapy in JCOG 1017, the non-PD rate was 77.2% and the response rate was 29.0% after 3 months of systemic therapy. By subtype, the non-PD rate was 78.2% for ER-HER2-, 75.4% for ER+HER2-, 92.9% for ER-HER2+, and 66.7% for ER+HER2+. The response rate was 36.4% for ER-HER2-, 13.4% for ER+HER2-, 81.0% for ER-HER2+, and 40.3% for ER+HER2+. In multivariable analysis, the non-PD rate was higher in postmenopausal (odds ratio [OR] 1.673, p=0.0240) and PgR-positive (OR 2.391, p= 0.0019) patients besides subtypes. Analysis results by drug were as follows; 1) hormone therapy (non-PD rate: 72.9%) was more effective for PgR-positive (OR 3.258, p< 0.0001), less effective for patients with visceral metastasis (OR 0.605, p=0.0334) and HER2-positive (OR 0.365, p=0.0016), 2) wPTX (non-PD rate: 76.1%) was no significant predictors of efficacy, 3) HPD/HPTX (non-PD rate: 92.7%) was more effective in patients with visceral metastasis (OR 15.818, p=0.0030). PD patients had much worse OS (hazard ratio [HR] 0.501, p< 0.0001) compared to non-PD, whereas responders had a little worse OS (HR 0.788, p=0.0538) compared to non-responders. Similar tendency was observed in any drug. Discussion Predictors of response to primary systemic therapy differed by subtype, with the need for treatment strategies tailored to PgR, HER2 expression, and the status of visceral metastasis. In the ER+HER2+ group, the efficacy of hormonal therapy alone was low, and combination therapy with molecular-targeted agents was considered necessary. The non-PD rate reflected prognosis in determining the efficacy of primary systemic therapy for dnST-IV. Citation Format: Tadahiko Shien, Akihiko Shimomura, Makoto Ishitobi, Kiyo Tanaka, Takahiro Tsukioki, Takashi Yamanaka, Fumitaka Hara, Kenjiro Aogi, Yasuhiro Yanagita, Michiko Tsuneizumi, Naohito Yamamoto, Hiroshi Matsumoto, Akihiko Suto, Ken-ichi Watanabe, Michiko Harao, Chizuko Kanbayashi, Mitsuya Ito, Keisei Anan, Shigeto Maeda, Keita Sasaki, Gakuto Ogawa, Haruhiko Fukuda, Hiroji Iwata. Effectiveness and prognostic predictors of primary systemic therapy for de-novo Stage IV breast cancer - Supplementary analysis of JCOG1017 PRIM-BC [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-06-06.

Using anticancer drugs as examples, we examined the possibility of reusing residual drugs. The use of residual drugs is not widespread owing to concerns regarding bacterial contamination. We combined anticancer drugs and bacteria to investigate their effects on bacterial growth. The anticancer drugs carboplatin, paclitaxel, etoposide, irinotecan, methotrexate, and 5-fluorouracil (5-FU) were mixed with Staphylococcus aureus, Enterococcus faecalis, Serratia marcescens, and Escherichia coli. After a certain period, the bacteria were counted. Irinotecan showed no antibacterial activity, whereas 5-FU exhibited high antibacterial activity against the tested bacteria. The 5-FU also showed a minimum inhibitory concentration value in the range of 8-80 μg/mL, depending on the bacterial species. 5-FU dose-dependently inhibited S. aureus growth at more than 0.8 µg/mL. Because protein synthesis systems are reportedly antibiotic targets, we used a cell-free protein synthesis system to confirm the mechanism of the antibacterial activity of the anticancer agent. 5-FU and methotrexate had direct inhibitory effects on protein synthesis. It has been suggested that even if residual drugs are contaminated with bacteria, there will be no microbial growth, or the microbes will be killed by the drug. With careful monitoring, 5-FU can potentially be used for antimicrobial purposes.

本稿は，クライストチャーチを拠点に活動する社会的企業のギャップフィラーを対象に，クリエイティブ・プレイスメイキングの挑戦と軌跡を，海外都市計画交流会でのヒアリング調査や現地調査により把握した．その結果，2010年から2011年に発生したカンタベリー地震からの復興過程に応じて，人々とその場所を結び付ける実験的で魅力的なプロジェクトを企画・運営するギャップフィラーの活動内容が多様化している一方，一貫してオープンで市民参加型の仮設的・暫定的な活動を行い，街の復興への人々の積極的な関与と新しい街の再構築のきっかけを先導的に提供していることを明らかにした．また，その根底には，創造性，遊び心，そして，市民的想像力に着目したアプローチが共通して存在しており，近年は「遊びの力」の活用に注目して，都市の可能性を実現するために挑戦していることを明らかにした．