An Analysis of Mechanisms Underlying the Antifibrinolytic Properties of Radiographic Contrast Agents

Background: Radiographic contrast agents inhibit fibrinolysis, although by poorly defined pathways. The purpose of this study was to define specific mechanisms by which contrast agents inhibit clot lysis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47998/1/11239_2004_Article_397950.pd

Electrosurgery and Implantable Electronic Devices: Review and Implications for Office‐Based Procedures

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86867/1/j.1524-4725.2011.02006.x.pd

A high-sensitivity method for identifying a rare subpopulation of patients with infective endocarditis for a prospective case-control study

Background Infective endocarditis (IE) is an uncommon disease, but it is associated with high morbidity and mortality. The low incidence and varied clinical presentation make identification of these patients recently admitted to hospitals particularly challenging. The authors designed a prospective electronic health record screening tool (PEHRST) to identify inpatients with IE for a prospective case-control study designed to determine levels of association between oral hygiene and periodontal disease indexes and IE. Methods The authors used PEHRST to identify, soon after admission, patients hospitalized with IE based on the presence of any 2 of the 4 screening criteria: orders for blood culture or echocardiography and completed consultations from infectious diseases or cardiovascular medicine. They determined the utility of this tool by comparing the prospectively generated PEHRST list of potential inpatients with IE with a retrospective list of inpatients with IE discharged during the same 2-year period. Results Of the 74,345 patients admitted during the study period, PEHRST identified 11,944 (16%) with at least 2 of the 4 screening criteria. Retrospective claims data showed that 198 patients were discharged during this time period with an IE diagnosis, all of whom had been identified by PEHRST (sensitivity = 100%; 95% CI, 98.2% to 100%; specificity = 84%; 95% CI, 83.9% to 84.4%). An analysis of the timing of the 4 screening criteria indicated that the median days were all within 24 hours of admission. Conclusions PEHRST made possible the identification of rare patients with IE soon after hospital admission with high sensitivity, allowing the parent study to achieve sufficient enrollment of cases for the primary outcome measure

Genetic background determines response to hemostasis and thrombosis

BACKGROUND: Thrombosis is the fatal and disabling consequence of cardiovascular diseases, the leading cause of mortality and morbidity in Western countries. Two inbred mouse strains, C57BL/6J and A/J, have marked differences in susceptibility to obesity, atherosclerosis, and vessel remodeling. However, it is unclear how these diverse genetic backgrounds influence pathways known to regulate thrombosis and hemostasis. The objective of this study was to evaluate thrombosis and hemostasis in these two inbred strains and determine the phenotypic response of A/J chromosomes in the C57BL/6J background. METHODS: A/J and C57Bl/6J mice were evaluated for differences in thrombosis and hemostasis. A thrombus was induced in the carotid artery by application of the exposed carotid to ferric chloride and blood flow measured until the vessel occluded. Bleeding and rebleeding times, as surrogate markers for thrombosis and hemostasis, were determined after clipping the tail and placing in warm saline. Twenty-one chromosome substitution strains, A/J chromosomes in a C57BL/6J background, were screened for response to the tail bleeding assay. RESULTS: Thrombus occlusion time was markedly decreased in the A/J mice compared to C57BL/6J mice. Tail bleeding time was similar in the two strains, but rebleeding time was markedly increased in the A/J mice compared to C57BL/6J mice. Coagulation times and tail morphology were similar, but tail collagen content was higher in A/J than C57BL/6J mice. Three chromosome substitution strains, B6-Chr5(A/J), B6-Chr11(A/J), and B6-Chr17(A/J), were identified with increased rebleeding time, a phenotype similar to A/J mice. Mice heterosomic for chromosomes 5 or 17 had rebleeding times similar to C57BL/6J mice, but when these two chromosome substitution strains, B6-Chr5(A/J )and B6-Chr17(A/J), were crossed, the A/J phenotype was restored in these doubly heterosomic progeny. CONCLUSION: These results indicate that susceptibility to arterial thrombosis and haemostasis is remarkably different in C57BL/and A/J mice. Three A/J chromosome substitution strains were identified that expressed a phenotype similar to A/J for rebleeding, the C57Bl/6J background could modify the A/J phenotype, and the combination of two A/J QTL could restore the phenotype. The diverse genetic backgrounds and differences in response to vascular injury induced thrombosis and the tail bleeding assay, suggest the potential for identifying novel genetic determinants of thrombotic risk