陽子とα粒子の放射線によるDNAにおける電子刺激ダイナミクス
1Department of Chemistry , The University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599 , United States.
Journal of the American Chemical Society
|March 14, 2019
まとめ
最初の原理のシミュレーションは,DNAのイオン照射がX線/ガンマ線効果と異なる穴を生成することを明らかにします. 刺激された穴の生成はエネルギー伝達率と相関せず,現在の放射線腫瘍学の仮定に挑戦します.
科学分野:
- 原子と分子物理学
- 化学物理学
- 放射線生物学
背景:
- イオン放射線はDNAに 電子刺激を引き起こし 放射線がん治療の理解に 極めて重要です
- 現在のモデルは,これらの相互作用を記述するために,しばしば線形応答理論に依存しています.
研究 の 目的:
- 陽子やアルファ粒子に対する DNAの不乱電子反応をシミュレートする
- イオンビームによるDNA損傷の記述における線形反応理論の妥当性を検証する.
- DNAの電子刺激の量子ダイナミクスを解明する
主な方法:
- 陽子とアルファ粒子に曝されたDNAの第一原理のダイナミクスシミュレーション
- シミュレーションの結果と線形応答理論の予測を比較する.
- 電子的な停止力とエネルギー転送率の分析
主要な成果:
- シミュレーションにより 陽子とアルファ粒子の放射線は DNAのイオン化と穴の発生を引き起こします
- X/ガンマ線照射と比較して,DNA刺激の行動において顕著な違いが観察されました.
- 刺激された穴の生成は,イオン速度に対するエネルギー転送率と直接的な相関を示さない.
結論:
- 線形反応理論では,イオン照射によって誘発される複雑な電子刺激を完全に捉えることはできません.
- この発見は放射線腫瘍学における エネルギー伝達とDNA損傷に関する 確立された仮定に異議を唱えるものです
- DNAの電子刺激の 量子力学に関する未経験の詳細を 提供しています
関連する概念動画
03:37Subatomic Particles
112.8K
Dalton was only partially correct about the particles that make up matter. All matter is composed of atoms, and atoms are composed of three smaller subatomic particles: protons, neutrons, and electrons. These three particles account for the mass and the charge of an atom.
112.8K
02:10The Nucleosome Core Particle
14.4K
Nucleosomes are the DNA-histone complex, where the DNA strand is wound around the histone core. The histone core is an octamer containing two copies of H2A, H2B, H3, and H4 histone proteins.
The paradox
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their main responsibility is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. While on the other hand, they must allow polymerase enzymes to access DNA...
The paradox
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their main responsibility is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. While on the other hand, they must allow polymerase enzymes to access DNA...
14.4K
01:24Electron Carriers
91.7K
Electron carriers can be thought of as electron shuttles. These compounds can easily accept electrons (i.e., be reduced) or lose them (i.e., be oxidized). They play an essential role in energy production because cellular respiration is contingent on the flow of electrons.
Over the many stages of cellular respiration, glucose breaks down into carbon dioxide and water. Electron carriers pick up electrons lost by glucose in these reactions, temporarily storing and releasing them into the electron...
Over the many stages of cellular respiration, glucose breaks down into carbon dioxide and water. Electron carriers pick up electrons lost by glucose in these reactions, temporarily storing and releasing them into the electron...
91.7K
01:07Electron Microscope Tomography and Single-particle Reconstruction
2.9K
Transmission electron microscopy (TEM) can be used to determine the 3D structure of biological samples with the help of techniques such as electron microscope tomography and single-particle reconstruction. While single-particle reconstruction can examine macromolecules and macromolecular complexes in vitro conditions only, tomography permits the study of cell components or small cells in vivo.
Electron Tomography
Electron tomography can be performed either in TEM or STEM (scanning transmission...
Electron Tomography
Electron tomography can be performed either in TEM or STEM (scanning transmission...
2.9K
01:28Electron Transport Chains
112.0K
The final stage of cellular respiration is oxidative phosphorylation that consists of two steps: the electron transport chain and chemiosmosis. The electron transport chain is a set of proteins found in the inner mitochondrial membrane in eukaryotic cells. Its primary function is to establish a proton gradient that can be used during chemiosmosis to produce ATP and generate electron carriers, such as NAD+ and FAD, that are used in glycolysis and the citric acid cycle.
The ETC is comprised of...
The ETC is comprised of...
112.0K
00:54Electron Behavior
108.0K
Overview
Electrons are negatively charged subatomic particles that are attracted to an orbit around the positively-charged nucleus of an atom. They reside in locations that are associated with energy levels called shells and are further organized into sub-shells and orbitals within each shell.
Electrons Orbit the Nucleus
Electrons are found in specific locations outside of the nucleus. The shell in which an electron resides indicates the general energy level of the electron: those closer to the...
Electrons are negatively charged subatomic particles that are attracted to an orbit around the positively-charged nucleus of an atom. They reside in locations that are associated with energy levels called shells and are further organized into sub-shells and orbitals within each shell.
Electrons Orbit the Nucleus
Electrons are found in specific locations outside of the nucleus. The shell in which an electron resides indicates the general energy level of the electron: those closer to the...
108.0K