Biomedical subjects
Agnieszka A Ardelt
Publications and source records attributed to Agnieszka A Ardelt.
Brainstem stroke following uncomplicated cervical epidural steroid injection.
BACKGROUND: Cervical epidural steroid injection treatment of radicular pain has become a common procedure. OBJECTIVES: To describe the clinical, radiologic, and autopsy findings of a 41-year-old patient treated with methylprednisolone acetate cervical epidural steroid injection, who developed a fatal hemorrhagic brainstem infarction and to discuss the possible mechanisms involved. DESIGN: Case report. SETTING: Pain management center and tertiary care hospital. RESULTS: Immediately following a seemingly uncomplicated epidural steroid injection at C5-6, the patient developed progressive symptoms of extensive brainstem and thalamic infarction (documented by magnetic resonance imaging and autopsy) with hemorrhagic conversion and hydrocephalus. Hemorrhage within the adventitia of the left vertebral artery, but no dissection, was found at the C5 vertebral level at necropsy. CONCLUSIONS: This case report shows the possibility of serious intracranial pathology resulting from cervical epidural steroid injection despite use of fluoroscopic guidance. Vascular spasm distant to the site of injection is a possible mechanism.
Estradiol regulates angiopoietin-1 mRNA expression through estrogen receptor-alpha in a rodent experimental stroke model.
BACKGROUND AND PURPOSE: Female, compared with male, animals are protected from cerebral ischemic injury. Physiological concentrations of 17beta-estradiol (E2) reduce damage in experimental stroke. E2 augments angiogenesis in reproductive organs and noncerebral vascular beds. We hypothesized that E2 protects brain in stroke through modulation of angiogenesis. We quantified molecular markers of angiogenesis and capillary density before and after unilateral middle cerebral artery occlusion (MCAO). METHODS: Female animals were ovariectomized, treated with 25 microg E2 or placebo implants, and subjected to 2-hour MCAO and 22 hours of reperfusion. Brain angiopoietin-1 (Ang-1), Ang-2, Tie-1, Tie-2, vascular endothelial growth factor (VEGF), VEGF R1, and VEGF R2 mRNA levels were determined by RNAse protection assays, and CD31-positive vessels were counted. RESULTS: E2, but not ischemia, upregulated cerebral Ang-1 mRNA by 49%. Capillary density was higher in the brains of E2-treated animals. In estrogen receptor-alpha knockout (ERKO) mice, E2-mediated induction of Ang-1 mRNA was absent relative to wild-type littermates. CONCLUSIONS: These results suggest that E2 increases Ang-1 and enhances capillary density in brain under basal conditions, priming the MCA territory for survival after experimental focal ischemia.