描述灰色物质与白色物质界面上的微结构过渡:实现和证明与年龄相关的差异
Joan Y Song1, Roman Fleysher2, Kenny Ye3
1Dominick P Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, United States.
NeuroImage
|January 14, 2025
概括
老化的大脑显示出一个不太明确的灰白物质接口 (GWI). 这种扩散MRI (dMRI) 方法揭示了GWI大脑微观结构的与年龄相关的变化,为衰老和大脑疾病提供了新的见解.
科学领域:
- 神经成像是一种神经成像.
- 大脑微观结构分析
- 衰老研究研究 衰老研究
背景情况:
- 灰质-白质接口 (GWI) 对大脑功能至关重要,易受病理影响.
- 由于部分体积效应,通过扩散MRI (dMRI) 评估GWI具有挑战性,导致它在许多研究中被排除在外.
研究的目的:
- 开发和验证一种新的dMRI方法,用于在GWI中表征微结构配置文件.
- 在GWI评估从灰质 (GM) 过渡到白质 (WM) 过渡的敏度.
主要方法:
- 利用了来自146名参与者 (18-91岁) 的横截面dMRI数据.
- 计算了6个大脑区域的微结构参数 (FA,AD,ODI,ICVF) 的总体GWI斜率.
- 使用线性模型评估了GWI斜率与年龄和生物性别的关联.
主要成果:
- 该方法成功地捕获了GWI内在的微观结构变化 (FA,AD,ODI,ICVF),其差异很小.
- 在所有地区都发现了FA斜率与年龄之间的显著反向关联,这表明随着年龄的增长,GWI变得不那么明显.
- 在特定的大脑区域确定了AD,ODI和ICVF斜率的与年龄相关的关联.
结论:
- 斜率大小与年龄的反向关联表明,在老化过程中GWI敏度会下降,可能是由于树突修剪,轴突退化和炎症.
- 这种新方法克服了GWI分析中以前的技术限制.
- 该方法在研究正常衰老和影响GWI的病理状况方面具有潜在的应用.
关键词:
衰老的衰老 衰老的衰老在 DTI 中,DTI 是指DTI.扩散式核磁共振成像 (MRI)转基因-WM 转基因-WM 转基因灰质与白质的界面是灰质和白质.接口 接口 接口 接口斜率的斜率是什么 斜率的斜率是什么更多相关视频
相关概念视频
Phase Transitions: Melting and Freezing
Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy becomes large enough to partially overcome the forces holding the molecules or ions of the solid in their fixed positions, and the solid begins the process of transitioning to the liquid state or melting. At this point, the temperature of the solid stops rising, despite the continual input of heat, and it remains constant until all of the solid is...
X-ray Crystallography
The size of the unit cell and the arrangement of atoms in a crystal may be determined from measurements of the diffraction of X-rays by the crystal, termed X-ray crystallography.
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
X-ray Diffraction of Biological Samples
X-ray diffraction or XRD is an analytical tool that utilizes X-rays to study ordered structures such as crystalline organic and inorganic samples, polycrystalline materials, proteins, carbohydrates, and drugs.
According to Bragg's law, when X-rays strike the sample positioned on a stage, the rays are scattered by the electron clouds around the sample atoms. The X-ray diffraction or scattering is caused by constructive interference of the X-ray waves that reflect off the internal crystal...
According to Bragg's law, when X-rays strike the sample positioned on a stage, the rays are scattered by the electron clouds around the sample atoms. The X-ray diffraction or scattering is caused by constructive interference of the X-ray waves that reflect off the internal crystal...
Phase Contrast and Differential Interference Contrast Microscopy
Phase-Contrast Microscopes
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...
Microcracking in Concrete
Microcracking in concrete refers to the tiny cracks that can form within the material even before any external load is applied. These microcracks typically occur at the interface between the coarse aggregate and the hydrated cement paste, often as a result of differential volume changes prompted by variations in stress-strain behavior, as well as thermal and moisture movement. Initially, these microcracks remain stable and do not grow substantially until the concrete is stressed to about 30...
Transition Zone
The transition zone in concrete is a critical area where aggregate meets cement paste, marked by a distinct porosity and weakness compared to the surrounding material. The adhesion around the aggregates is primarily due to Van Der Waals forces. The voids within this zone influence its robustness; initially, it is less durable than the surrounding bulk mortar due to larger voids. Initially, when concrete is compacted, a higher water-cement ratio near the aggregates leads to the formation of...


