Fig. 1.

(A) Aortic wall collagen levels were assessed by the hydroxyproline/proline ratio, and the extent of intramolecular collagen cross-links was assessed by the number of hydroxylysyl pyridinoline and lysyl pyridinoline cross-links per triple helix. Open box, control; light gray box, Marfan syndrome; dark gray box, AAA; ^●, P < 0.00001. (B) Collagen deposition (Sirius Red staining) in normal aortic wall and aneurysmal wall in Marfan syndrome and AAA. The images are oriented with the media layer in the upper half and the adventitial layer in the lower half.