VERY LOW FREQUENCY EPR IMAGING FOR IN VIVO PHYSIOLOGY

用于体内生理学的极低频 EPR 成像

• 批准号: 6794239
• 负责人: HOWARD J HALPERN
• 金额: $ 7.02万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-30 至 2005-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6794239
• 关键词: biomedical equipment resource; biomedical resource; electron spin resonance spectroscopy; imaging /visualization /scanning; technology /technique development

A novel technician has been developed which will image physiologic characteristics and toxic radicals in living tissues of animals and humans. This information has, heretofore, been unavailable. The technique has been slowly developing in a number of laboratories throughout the world despite widespread misconceptions about the possibility of obtaining good EPR signals at such low frequencies. However, recent advances in spectroscopic technique and spin probe development, as well as the understanding of the information that can be provided, poise this technique on the verge of breakthrough. The technique uses very low frequency electron paramagnetic resonance imaging, VLF-EPRI. Very low frequency (100 to 300 MHZ) is necessary to allow the electromagnetic energy, which stimulates resonant absorption, to penetrate deep into the tissue of animals. In many applications, the spectra are derived from a non-toxic spin probe, similar or identical to magnetic resonance imaging contrast material, which is infused into animal tissues. The spin probe, similar or identical to magnetic resonance imaging contrast material, which is infused into animal tissues. The spin probe can target various fluid compartment in tissues. Changes in the spectrum of the spin probe report local oxygen concentration with high accuracy. As a byproduct of the oxygen measurement, the spectrum can also report microviscosity, which may be important for cellular proliferation. Spin labeling of medicinal agents may allow in vivo images of their pharmacodynamics. These images deep in animal tissues have been recently reported with VLF-EPRI. Both signaling and toxic free radicals can be detected with VLF-EPRI in vivo. Nitric oxide and hydroxyl radical have been detected in animal tissues with VLF-EPRI. These early measurements have been relatively crude. However, there are clear paths to improvements in physiologic sensitivity and spatial resolution by orders of magnitude. We propose the development of center facilities with an array of VLF-EPRI spectroscopic imagers to achieve this improvement in sensitivity and resolution. It would exist within a major medical center. This would offer adjacent, coordinated animal care, access to MRI/Spiral CT scanning and advanced image correlation capability. The VLF-EPRI facilities would also coordinate with spin probe and spin trap synthesis investigators to improve the general technique and tailor it to the needs of an individual researcher. We envision the development of a unique center offering researchers the capability of generating new physiologic information from VLF-EPRI.

一种新的技术已经开发出来，将图像的生理特征和有毒的自由基在动物和人类的活组织。这方面的资料迄今尚未提供。该技术已在世界各地的一些实验室中缓慢发展，尽管对在如此低的频率下获得良好EPR信号的可能性存在广泛的误解。然而，最近的进展，光谱技术和自旋探针的发展，以及了解的信息，可以提供，平衡这种技术的突破的边缘。该技术使用甚低频电子顺磁共振成像（VLF-EPRI）。非常低的频率（100至300兆赫）是必要的，以允许电磁能量，刺激共振吸收，深入渗透到动物的组织。在许多应用中，光谱来源于注入动物组织中的与磁共振成像对比材料相似或相同的无毒自旋探针。自旋探针，与磁共振成像造影剂相似或相同，注入动物组织。自旋探针可以靶向组织中的各种流体隔室。自旋探针光谱的变化以高精度报告局部氧浓度。作为氧测量的副产品，光谱还可以报告微粘度，这对细胞增殖可能很重要。药物的自旋标记可允许其药效学的体内图像。这些图像在动物组织深处最近已报告与VLF-EPRI。信号和毒性自由基都可以用VLF-EPRI在体内检测。用VLF-EPRI检测了动物组织中的一氧化氮和羟自由基。这些早期的测量相对粗糙。然而，有明确的路径，以改善生理灵敏度和空间分辨率的数量级。我们建议发展中心设施与一个阵列的VLF-EPRI光谱成像仪，以实现这种提高灵敏度和分辨率。它将存在于一个主要的医疗中心。这将提供相邻的、协调的动物护理，获得MRI/螺旋CT扫描和先进的图像相关能力。VLF-EPRI设施还将与自旋探针和自旋阱合成研究人员协调，以改进一般技术，并使其适合个别研究人员的需要。我们设想发展一个独特的中心，为研究人员提供从VLF-EPRI产生新的生理信息的能力。