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Biology subjects

Reed, M. J.

Publications and source records attributed to Reed, M. J..

2 recordsLinked to original sources

Plasma Cell-Free DNA in Acute and Chronic Aortic Syndromes.

Acute aortic syndromes and other acute aortic events are commonly misdiagnosed and associated with high mortality and morbidity. There is need for a blood-based biomarker to indicate the acutely unstable aorta. Plasma cell-free DNA (cfDNA) is an established diagnostic marker in prenatal testing and cancer. Its use as a potential diagnostic marker in aortic disease remains to be demonstrated. We found that plasma short-fragment (50-700bp) cfDNA concentration is significantly increased in patients with both acute and chronic aortic disease compared with several control groups, and is significantly increased in acute versus chronic aortic disease. Plasma sf-cfDNA may differentiate acute aortic syndromes from other acute presentations of chest pain with good diagnostic accuracy and could prove a significant advance in the management of aortic disease.

genomics↗

Contrast-enhanced ultrasound imaging detects anatomical and functional changes in rat cervical spine microvasculature with normal aging

Normal aging is associated with significant deleterious cerebrovascular changes; these have been implicated in disease pathogenesis and increased susceptibility to ischemic injury. While these changes are well documented in the brain, few studies have been conducted in the spinal cord. Here, we utilize specialized contrast-enhanced ultrasound (CEUS) imaging to investigate age-related changes in cervical spinal vascular anatomy and hemodynamics in male Fisher 344 rats, a common strain in aging research. Aged rats (24-26 mo., N=6) exhibited significant tortuosity in the anterior spinal artery and elevated vascular resistance compared to adults (4-6 mo., N=6; tortuosity index 2.20{+/-}0.15 vs 4.74{+/-}0.45, p<0.05). Baseline blood volume was lower in both larger vessels and the microcirculation in the aged cohort, specifically in white matter (4.44e14{+/-}1.37e13 vs 3.66e14{+/-}2.64e13 CEUS bolus AUC, p<0.05). To elucidate functional differences, animals were exposed to a hypoxia challenge; whereas adult rats exhibited significant functional hyperemia in both gray and white matter (GM: 1.13{+/-}0.10-fold change from normoxia, p<0.05; WM: 1.16{+/-}0.13, p<0.05), aged rats showed no response. Immunohistochemistry revealed reduced pericyte coverage and activated microglia behavior in aged rats, which may partially explain the lack of vascular response. This study provides the first in vivo description of age-related hemodynamic differences in the cervical spinal cord.

neuroscience↗