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: 6394661
• 负责人: HOWARD J HALPERN
• 金额: $ 83.64万
• 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 2004-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6394661
• 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.

一种新颖的技术已经开发出来，可以对动物和人类活组织中的生理特征和有毒自由基进行成像。迄今为止，该信息尚不可用。尽管人们普遍对在如此低的频率下获得良好 EPR 信号的可能性存在误解，但该技术在世界各地的许多实验室中一直在缓慢发展。然而，光谱技术和自旋探针开发的最新进展，以及对所提供信息的理解，使这项技术处于突破的边缘。该技术使用极低频电子顺磁共振成像（VLF-EPRI）。需要非常低的频率（100 至 300 MHZ）才能使电磁能刺激共振吸收，深入渗透到动物组织中。在许多应用中，光谱源自无毒的自旋探针，与注入动物组织的磁共振成像对比材料相似或相同。自旋探针与磁共振成像对比材料相似或相同，被注入动物组织中。自旋探针可以瞄准组织中的各种液体隔室。自旋探针光谱的变化可以高精度地报告局部氧浓度。作为氧气测量的副产品，光谱还可以报告微粘度，这对于细胞增殖可能很重要。药物的自旋标记可以实现其药效学的体内图像。最近通过 VLF-EPRI 报道了这些动物组织深处的图像。使用 VLF-EPRI 可以在体内检测信号自由基和有毒自由基。 VLF-EPRI 已在动物组织中检测到一氧化氮和羟自由基。这些早期的测量相对粗糙。然而，有明确的途径可以将生理敏感性和空间分辨率提高几个数量级。我们建议开发配备一系列 VLF-EPRI 光谱成像仪的中心设施，以实现灵敏度和分辨率的提高。它将存在于一个主要的医疗中心内。这将提供相邻、协调的动物护理、MRI/螺旋 CT 扫描和先进的图像相关功能。 VLF-EPRI 设施还将与自旋探针和自旋陷阱合成研究人员协调，以改进通用技术并根据个别研究人员的需求进行定制。我们设想建立一个独特的中心，为研究人员提供从 VLF-EPRI 生成新生理信息的能力。