Creation of Mo/Tc@C60 and Au@C60 and molecular-dynamics simulations

The formation of middle- and/or high-weight atom (Mo, Au)-incorporated fullerenes was investigated using radionuclides produced by nuclear reactions. From the trace radioactivities of ⁹⁹Mo/⁹⁹mTc or ¹⁹⁴Au after high-performance liquid chromatography, it was found that the formation of endohedral and/or heterofullerene fullerenes in ⁹⁹Mo/⁹⁹mTc and ¹⁹⁴Au atoms could occur by a recoil process following the nuclear reactions. Furthermore, the ⁹⁹mTc (and ¹⁹⁴Au) atoms recoiled against β-decay remained present inside these cages. To confirm the produced materials experimentally, ab initio molecular dynamics (MD) simulations based on an all-electron mixed-basis approach were performed. The possibility of the formation of endohedral fullerenes containing Mo/Tc and Au atoms is verified; here, the formation of heterofullerenes is excluded by MD simulations. These findings suggest that radionuclides stably encapsulated by fullerenes could potentially play a valuable role in diagnostic nuclear medicine

非破壊的で迅速に骨形成を評価できるマーカーとしての培養液中カルシウム濃度について

Artificial bones made of β-tricalcium phosphate (β-TCP) combined with bone marrow-derived mesenchymal stromal cells (BM-MSCs) are used for effective reconstruction of bone defects caused by genetic defects, traumatic injury, or surgical resection of bone tumors. However, the selection of constructs with high osteogenic potential before implantation is challenging. The purpose of this study was to determine whether the calcium concentration in BM-MSC culture medium can be used as a nondestructive and simple osteogenic marker for selecting tissue-engineered grafts constructed using β-TCP and BM-MSCs. We prepared three cell passages of BM-MSCs derived from three 7-week-old, male Fischer 344 rats; the cells were cultured in osteoinductive medium in the presence of β-TCP for 15 days. The medium was replaced with fresh medium on day 1 in culture and subsequently changed every 48 h; it was collected for measurement of osteocalcin secretion and calcium concentration by enzyme-linked immunosorbent assay and X-ray fluorescence spectrometry, respectively. After cultivation, the constructs were implanted subcutaneously into the backs of recipient rats. Four weeks after implantation, the alkaline phosphatase (ALP) activity and osteocalcin content of the constructs were measured. A strong inverse correlation was observed between the calcium concentration in the medium and the ALP activity and osteocalcin content of the constructs, with Pearson's correlation coefficients of 0.92 and 0.90, respectively. These results indicate that tissue-engineered bone with high osteogenic ability can be selected before implantation based on low calcium content of the culture medium, resulting in successful bone formation after implantation. This nondestructive, simple method shows great promise for assessing the osteogenic ability of tissue-engineered bone.博士（医学）・乙第1411号・平成29年11月24日Copyright © 2017 Cognizant, LLC. The articles contained in the following journals published by Cognizant, LLC are "open access articles" subject to the terms of the Creative Commons Attribution Non-Commercial (CC BY NC) license(https://creativecommons.org/licenses/by-nc/3.0/). That license permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. The articles are therefore free to read, download, cite and share with others

ケイ酸/亜鉛置換ストロンチウムアパタイトコーティングによるβ-リン酸カルシウムの骨誘導能促進効果

Background: β-Tricalcium phosphate (β-TCP) is a popular synthetic bone graft substitute with excellent osteoconductive properties and bioabsorbability. However, its osteoinductive properties are inferior to those of autologous or allogeneic bone. Trace elements such as strontium (Sr), silica (Si), and zinc (Zn) have been reported to promote osteogenesis in materials. In this study, we aimed to determine whether a Si/Zn-substituted Sr apatite coating of β-TCP could enhance osteoinductive properties. Methods: The apatite-coated β-TCP disks were prepared using nanoparticle suspensions of silicate-substituted Sr apatite (SrSiP) or silicate- and Zn-co-substituted Sr apatite (SrZnSiP). Bone marrow mesenchymal cells (BMSCs) from rat femur were cultured and subsequently seeded at a density of 1.0 × 106/cm2 onto apatite-coated and non-coated β-TCP disks. In vitro, the β-TCP disks were then placed in osteogenic medium, and lactate dehydrogenase (LDH) activity was measured from supernatants after culture for 2 days. Additionally, after culture for 14 days, the mRNA expression of genes encoding osteocalcin (OC), alkaline phosphatase (ALP), bone morphogenetic protein-2 (BMP-2), and vascular endothelial growth factor (VEGF) was evaluated by qRT-PCR. In vivo, the β-TCP disks were transplanted subcutaneously into rats that were sacrificed after 4 weeks. Then, the harvested disks were evaluated biochemically (ALP activity, OC content, mRNA expression of OC, ALP, BMP-2, and VEGF measured by qRT-PCR), radiologically, and histologically. Results: Significantly higher mRNA expression of almost all evaluated osteogenic and angiogenic genes was observed in the SrZnSiP and SrSiP groups than in the non-coated group, with no significant cytotoxicity elicited by the apatite coating in vitro. Moreover, in vivo, the SrZnSiP and SrSiP groups showed significantly higher osteogenic and angiogenic gene expression and higher ALP activity and OC content than the non-coated group (P < 0.05). Radiological and histopathological findings revealed abundant bone formation in the apatite-coated group. Conclusions: Our findings indicate that apatite coating of β-TCP improves osteoinductive properties without inducing significant cytotoxicity.博士（医学）・甲第805号・令和3年12月21日© 2021. The Author(s).Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data

Interactive effects of level and instability of situational motivation for learning during class

本研究では、大学生を対象に、授業中の学習における状況的動機づけと深い処理方略、学業達成との関連を検討した。特に、状況的動機づけを動機づけレベルと動機づけの変動性の2側面から捉え、それらの交互作用効果について着目した。対象の授業における調査および2回のテストに参加した、2つの大学の104名の大学生のデータを分析対象とした。大学、文脈的動機づけ、1回目のテスト得点を統制して階層的重回帰分析を行った結果、深い処理方略に対して動機づけレベルと変動性との交互作用効果が見られた。単純傾斜分析の結果、動機づけの変動が大きい場合、動機づけレベルが高いほど深い処理方略を多く使用することが示された。一方で、動機づけの変動が小さい場合には、深い処理方略に対する動機づけレベルの効果は示されなかった。また、階層的重回帰分析の結果、対象の授業におけるテスト得点に対しては動機づけレベルのみが正の関連を示した。本研究は、科学研究費助成事業（若手研究 課題番号：19K14398）の助成を受けて行われた

チュウガクセイ ノ イジメ ニ タイスル タイド ガ イジメ カンヨ コウドウ ニ オヨボス エイキョウ イジメ IAT サクセイ ノ ココロミ

本研究は，科学研究費助成事業（学術研究助成基金助成金・基盤研究（C），課題番号：26380867）の助成を受けた。本研究の一部は，the 31st International Congress of Psychologyにおいて発表された