Successful redo open thoracoabdominal aortic aneurysm surgery in a patient with vascular Ehlers-Danlos syndrome: A case report.

We report a case of a 63-year-old woman diagnosed with vascular Ehlers-Danlos syndrome (vEDS) who survived two prophylactic surgeries for the dilatation of a thoracoabdominal aortic aneurysm. She initially developed acute type B aortic dissection at the age of 44 years. Five years later, her dissected descending aorta was enlarged to 54 mm; thus, the descending aorta was replaced as the first surgery. Fortunately, the intra- and post-operative courses were uneventful. Fourteen years post her first surgery, the dissected thoracoabdominal aorta distal to the graft expanded to 53 mm; however, no anastomotic leakage was observed. Genetic testing revealed a COL3A1 abnormality, confirming the diagnosis of vEDS. Thoracoabdominal aorta replacement using deep hypothermia circulatory arrest was performed because of the high risk of aortic aneurysm rupture. The second surgery was performed without complications, and no complications were observed 13 months post-surgery. The major reason for a successful surgery in this patient was the relatively low vascular fragility associated with vEDS. This case demonstrates that there may be considerable individual differences in vascular fragility in patients with vEDS. Thus, surgical repair, along with endovascular therapy, might still be a beneficial option for patients with vEDS having large aortic aneurysms and a high risk of rupture. Learning objective: Prophylactic surgery for vascular lesions in Ehlers-Danlos syndrome (vEDS) is generally not recommended because of its high vascular fragility. However, if a patient with vEDS has an aortic aneurysm that is at a very high risk of rupture, aggressive treatment is a plausible option as there may be considerable individual differences in vascular fragility among patients with vEDS.

Kinetics of the interfacial curing reaction for an epoxy-amine mixture.

A better understanding of the chemical reaction between epoxy and amine compounds at a solid interface is crucial for the design and fabrication of materials with appropriate adhesive strength. Here, we examined the curing reaction kinetics of epoxy phenol novolac and 4,4'-diaminodiphenyl sulfone at the outermost interface using sum-frequency generation spectroscopy, and X-ray and neutron reflectivity in conjunction with a full atomistic molecular dynamics simulation. The reaction rate constant was much larger at the quartz interface than in the bulk. While the apparent activation energy at the quartz interface obtained from an Arrhenius plot was almost identical to the bulk value, the frequency factor at the quartz interface was greater than that in the bulk. These results could be explained in terms of the densification and orientation of reactants at the interface, facilitating the encounter of the reactants present.