Secondary aortoenteric fistula: a narrative review of the view of the surgeon.

Aortoenteric fistula (AEF) is defined as the abnormal communication between the aorta and the gastrointestinal tract. AEFs are divided into primary and secondary usually after abdominal aortic aneurysm (AAA) recovery and are a rare but quite dangerous cause of gastrointestinal bleeding that the general surgeon may face during his/her career. Secondary AEF was first described in 1953 to a 44-year-old woman 3 months after an AAA operation.

Photophysical characterization of hematoporphyrin incorporated within collagen gels.

Physical properties of hematoporphyrin-enriched collagen gels relevant to the photodynamic treatment of cancer are characterized. The incorporation of the sensitizer within the gels does not affect either the structure of the gel or the absorption and fluorescence spectra of the sensitizer. The gel-embedded sensitizer photodegrades efficiently with the formation of a product emitting near 635 nm.